--- /dev/null
+/* ==========================================================================
+ * dns.c - Recursive, Reentrant DNS Resolver.
+ * --------------------------------------------------------------------------
+ * Copyright (c) 2008, 2009, 2010 William Ahern
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to permit
+ * persons to whom the Software is furnished to do so, subject to the
+ * following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+ * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+ * USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * ==========================================================================
+ */
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifndef _XOPEN_SOURCE
+#define _XOPEN_SOURCE 600
+#endif
+
+#undef _BSD_SOURCE
+#define _BSD_SOURCE
+
+#undef _DARWIN_C_SOURCE
+#define _DARWIN_C_SOURCE
+
+#include <stddef.h> /* offsetof() */
+#include <stdint.h> /* uint32_t */
+#include <stdlib.h> /* malloc(3) realloc(3) free(3) rand(3) random(3) arc4random(3) */
+#include <stdio.h> /* FILE fopen(3) fclose(3) getc(3) rewind(3) */
+
+#include <string.h> /* memcpy(3) strlen(3) memmove(3) memchr(3) memcmp(3) strchr(3) strsep(3) strcspn(3) */
+#include <strings.h> /* strcasecmp(3) strncasecmp(3) */
+
+#include <ctype.h> /* isspace(3) isdigit(3) */
+
+#include <time.h> /* time_t time(2) */
+
+#include <signal.h> /* sig_atomic_t */
+
+#include <errno.h> /* errno EINVAL ENOENT */
+
+#undef NDEBUG
+#include <assert.h> /* assert(3) */
+
+#if _WIN32
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#else
+#include <sys/types.h> /* FD_SETSIZE socklen_t */
+#include <sys/select.h> /* FD_ZERO FD_SET fd_set select(2) */
+#include <sys/socket.h> /* AF_INET AF_INET6 AF_UNIX struct sockaddr struct sockaddr_in struct sockaddr_in6 socket(2) */
+
+#if defined(AF_UNIX)
+#include <sys/un.h> /* struct sockaddr_un */
+#endif
+
+#include <fcntl.h> /* F_SETFD F_GETFL F_SETFL O_NONBLOCK fcntl(2) */
+
+#include <unistd.h> /* gethostname(3) close(2) */
+
+#include <poll.h> /* POLLIN POLLOUT */
+
+#include <netinet/in.h> /* struct sockaddr_in struct sockaddr_in6 */
+
+#include <arpa/inet.h> /* inet_pton(3) inet_ntop(3) htons(3) ntohs(3) */
+
+#include <netdb.h> /* struct addrinfo */
+#endif
+
+#include "dns.h"
+
+
+/*
+ * S T A N D A R D M A C R O S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+#ifndef MIN
+#define MIN(a, b) (((a) < (b))? (a) : (b))
+#endif
+
+
+#ifndef MAX
+#define MAX(a, b) (((a) > (b))? (a) : (b))
+#endif
+
+
+#ifndef lengthof
+#define lengthof(a) (sizeof (a) / sizeof (a)[0])
+#endif
+
+#ifndef endof
+#define endof(a) (&(a)[lengthof((a))])
+#endif
+
+
+/*
+ * D E B U G M A C R O S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+int dns_debug = 0;
+
+#if DNS_DEBUG
+
+#undef DNS_DEBUG
+#define DNS_DEBUG dns_debug
+
+#define DNS_SAY_(fmt, ...) \
+ do { if (DNS_DEBUG > 0) fprintf(stderr, fmt "%.1s", __func__, __LINE__, __VA_ARGS__); } while (0)
+#define DNS_SAY(...) DNS_SAY_("@@ (%s:%d) " __VA_ARGS__, "\n")
+#define DNS_HAI DNS_SAY("HAI")
+
+#define DNS_SHOW_(P, fmt, ...) do { \
+ if (DNS_DEBUG > 1) { \
+ fprintf(stderr, "@@ BEGIN * * * * * * * * * * * *\n"); \
+ fprintf(stderr, "@@ " fmt "%.0s\n", __VA_ARGS__); \
+ dns_p_dump((P), stderr); \
+ fprintf(stderr, "@@ END * * * * * * * * * * * * *\n\n"); \
+ } \
+} while (0)
+
+#define DNS_SHOW(...) DNS_SHOW_(__VA_ARGS__, "")
+
+#else /* !DNS_DEBUG */
+
+#undef DNS_DEBUG
+#define DNS_DEBUG 0
+
+#define DNS_SAY(...)
+#define DNS_HAI
+#define DNS_SHOW(...)
+
+#endif /* DNS_DEBUG */
+
+
+/*
+ * V E R S I O N R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+const char *dns_vendor(void) {
+ return DNS_VENDOR;
+} /* dns_vendor() */
+
+
+int dns_v_rel(void) {
+ return DNS_V_REL;
+} /* dns_v_rel() */
+
+
+int dns_v_abi(void) {
+ return DNS_V_ABI;
+} /* dns_v_abi() */
+
+
+int dns_v_api(void) {
+ return DNS_V_API;
+} /* dns_v_api() */
+
+
+/*
+ * E R R O R R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+#if _WIN32
+
+#define DNS_EINTR WSAEINTR
+#define DNS_EINPROGRESS WSAEINPROGRESS
+#define DNS_EISCONN WSAEISCONN
+#define DNS_EWOULDBLOCK WSAEWOULDBLOCK
+#define DNS_EALREADY WSAEALREADY
+#define DNS_EAGAIN EAGAIN
+#define DNS_ETIMEDOUT WSAETIMEDOUT
+
+#define dns_syerr() ((int)GetLastError())
+#define dns_soerr() ((int)WSAGetLastError())
+
+#else
+
+#define DNS_EINTR EINTR
+#define DNS_EINPROGRESS EINPROGRESS
+#define DNS_EISCONN EISCONN
+#define DNS_EWOULDBLOCK EWOULDBLOCK
+#define DNS_EALREADY EALREADY
+#define DNS_EAGAIN EAGAIN
+#define DNS_ETIMEDOUT ETIMEDOUT
+
+#define dns_syerr() errno
+#define dns_soerr() errno
+
+#endif
+
+
+const char *dns_strerror(int error) {
+ switch (error) {
+ case DNS_ENOBUFS:
+ return "DNS packet buffer too small";
+ case DNS_EILLEGAL:
+ return "Illegal DNS RR name or data";
+ case DNS_EORDER:
+ return "Attempt to push RR out of section order";
+ case DNS_ESECTION:
+ return "Invalid section specified";
+ case DNS_EUNKNOWN:
+ return "Unknown DNS error";
+ default:
+ return strerror(error);
+ } /* switch() */
+} /* dns_strerror() */
+
+
+/*
+ * A T O M I C R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+static unsigned dns_atomic_inc(dns_atomic_t *i) {
+ return (*i)++;
+} /* dns_atomic_inc() */
+
+
+static unsigned dns_atomic_dec(dns_atomic_t *i) {
+ return (*i)--;
+} /* dns_atomic_dec() */
+
+
+/*
+ * C R Y P T O R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * P R N G
+ */
+
+#ifndef DNS_RANDOM
+#if defined(HAVE_ARC4RANDOM) \
+ || defined(__OpenBSD__) \
+ || defined(__FreeBSD__) \
+ || defined(__NetBSD__) \
+ || defined(__APPLE__)
+#define DNS_RANDOM arc4random
+#elif __linux
+#define DNS_RANDOM random
+#else
+#define DNS_RANDOM rand
+#endif
+#endif
+
+#define DNS_RANDOM_arc4random 1
+#define DNS_RANDOM_random 2
+#define DNS_RANDOM_rand 3
+#define DNS_RANDOM_RAND_bytes 4
+
+#define DNS_RANDOM_OPENSSL (DNS_RANDOM_RAND_bytes == DNS_PP_XPASTE(DNS_RANDOM_, DNS_RANDOM))
+
+#if DNS_RANDOM_OPENSSL
+#include <openssl/rand.h>
+#endif
+
+static unsigned dns_random_(void) {
+#if DNS_RANDOM_OPENSSL
+ unsigned r;
+
+ assert(1 == RAND_bytes((unsigned char *)&r, sizeof r));
+
+ return r;
+#else
+ return DNS_RANDOM();
+#endif
+} /* dns_random_() */
+
+unsigned (*dns_random)(void) __attribute__((weak)) = &dns_random_;
+
+
+/*
+ * P E R M U T A T I O N G E N E R A T O R
+ */
+
+#define DNS_K_TEA_KEY_SIZE 16
+#define DNS_K_TEA_BLOCK_SIZE 8
+#define DNS_K_TEA_CYCLES 32
+#define DNS_K_TEA_MAGIC 0x9E3779B9U
+
+struct dns_k_tea {
+ uint32_t key[DNS_K_TEA_KEY_SIZE / sizeof (uint32_t)];
+ unsigned cycles;
+}; /* struct dns_k_tea */
+
+
+static void dns_k_tea_init(struct dns_k_tea *tea, uint32_t key[], unsigned cycles) {
+ memcpy(tea->key, key, sizeof tea->key);
+
+ tea->cycles = (cycles)? cycles : DNS_K_TEA_CYCLES;
+} /* dns_k_tea_init() */
+
+
+static void dns_k_tea_encrypt(struct dns_k_tea *tea, uint32_t v[], uint32_t *w) {
+ uint32_t y, z, sum, n;
+
+ y = v[0];
+ z = v[1];
+ sum = 0;
+
+ for (n = 0; n < tea->cycles; n++) {
+ sum += DNS_K_TEA_MAGIC;
+ y += ((z << 4) + tea->key[0]) ^ (z + sum) ^ ((z >> 5) + tea->key[1]);
+ z += ((y << 4) + tea->key[2]) ^ (y + sum) ^ ((y >> 5) + tea->key[3]);
+ }
+
+ w[0] = y;
+ w[1] = z;
+
+ return /* void */;
+} /* dns_k_tea_encrypt() */
+
+
+/*
+ * Permutation generator, based on a Luby-Rackoff Feistel construction.
+ *
+ * Specifically, this is a generic balanced Feistel block cipher using TEA
+ * (another block cipher) as the pseudo-random function, F. At best it's as
+ * strong as F (TEA), notwithstanding the seeding. F could be AES, SHA-1, or
+ * perhaps Bernstein's Salsa20 core; I am naively trying to keep things
+ * simple.
+ *
+ * The generator can create a permutation of any set of numbers, as long as
+ * the size of the set is an even power of 2. This limitation arises either
+ * out of an inherent property of balanced Feistel constructions, or by my
+ * own ignorance. I'll tackle an unbalanced construction after I wrap my
+ * head around Schneier and Kelsey's paper.
+ *
+ * CAVEAT EMPTOR. IANAC.
+ */
+#define DNS_K_PERMUTOR_ROUNDS 8
+
+struct dns_k_permutor {
+ unsigned stepi, length, limit;
+ unsigned shift, mask, rounds;
+
+ struct dns_k_tea tea;
+}; /* struct dns_k_permutor */
+
+
+static inline unsigned dns_k_permutor_powof(unsigned n) {
+ unsigned m, i = 0;
+
+ for (m = 1; m < n; m <<= 1, i++)
+ ;;
+
+ return i;
+} /* dns_k_permutor_powof() */
+
+static void dns_k_permutor_init(struct dns_k_permutor *p, unsigned low, unsigned high) {
+ uint32_t key[DNS_K_TEA_KEY_SIZE / sizeof (uint32_t)];
+ unsigned width, i;
+
+ p->stepi = 0;
+
+ p->length = (high - low) + 1;
+ p->limit = high;
+
+ width = dns_k_permutor_powof(p->length);
+ width += width % 2;
+
+ p->shift = width / 2;
+ p->mask = (1U << p->shift) - 1;
+ p->rounds = DNS_K_PERMUTOR_ROUNDS;
+
+ for (i = 0; i < lengthof(key); i++)
+ key[i] = dns_random();
+
+ dns_k_tea_init(&p->tea, key, 0);
+
+ return /* void */;
+} /* dns_k_permutor_init() */
+
+
+static unsigned dns_k_permutor_F(struct dns_k_permutor *p, unsigned k, unsigned x) {
+ uint32_t in[DNS_K_TEA_BLOCK_SIZE / sizeof (uint32_t)], out[DNS_K_TEA_BLOCK_SIZE / sizeof (uint32_t)];
+
+ memset(in, '\0', sizeof in);
+
+ in[0] = k;
+ in[1] = x;
+
+ dns_k_tea_encrypt(&p->tea, in, out);
+
+ return p->mask & out[0];
+} /* dns_k_permutor_F() */
+
+
+static unsigned dns_k_permutor_E(struct dns_k_permutor *p, unsigned n) {
+ unsigned l[2], r[2];
+ unsigned i;
+
+ i = 0;
+ l[i] = p->mask & (n >> p->shift);
+ r[i] = p->mask & (n >> 0);
+
+ do {
+ l[(i + 1) % 2] = r[i % 2];
+ r[(i + 1) % 2] = l[i % 2] ^ dns_k_permutor_F(p, i, r[i % 2]);
+
+ i++;
+ } while (i < p->rounds - 1);
+
+ return ((l[i % 2] & p->mask) << p->shift) | ((r[i % 2] & p->mask) << 0);
+} /* dns_k_permutor_E() */
+
+static unsigned dns_k_permutor_step(struct dns_k_permutor *p) {
+ unsigned n;
+
+ do {
+ n = dns_k_permutor_E(p, p->stepi++);
+ } while (n >= p->length);
+
+ return n + (p->limit + 1 - p->length);
+} /* dns_k_permutor_step() */
+
+
+/*
+ * Simple permutation box. Useful for shuffling rrsets from an iterator.
+ * Uses AES s-box to provide good diffusion.
+ *
+ * Seems to pass muster under runs test.
+ *
+ * $ for i in 0 1 2 3 4 5 6 7 8 9; do ./dns shuffle-16 > /tmp/out; done
+ * $ R -q -f /dev/stdin 2>/dev/null <<-EOF | awk '/p-value/{ print $8 }'
+ * library(lawstat)
+ * runs.test(scan(file="/tmp/out"))
+ * EOF
+ */
+static unsigned short dns_k_shuffle16(unsigned short n, unsigned s) {
+ static const unsigned char sbox[256] =
+ { 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5,
+ 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
+ 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0,
+ 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
+ 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc,
+ 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
+ 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a,
+ 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
+ 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0,
+ 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
+ 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b,
+ 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
+ 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85,
+ 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
+ 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5,
+ 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
+ 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17,
+ 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
+ 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88,
+ 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
+ 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,
+ 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
+ 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9,
+ 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
+ 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6,
+ 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
+ 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e,
+ 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
+ 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94,
+ 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
+ 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68,
+ 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 };
+ unsigned char a, b;
+ unsigned i;
+
+ a = 0xff & (n >> 0);
+ b = 0xff & (n >> 8);
+
+ for (i = 0; i < 4; i++) {
+ a ^= 0xff & s;
+ a = sbox[a] ^ b;
+ b = sbox[b] ^ a;
+ s >>= 8;
+ }
+
+ return ((0xff00 & (a << 8)) | (0x00ff & (b << 0)));
+} /* dns_k_shuffle16() */
+
+
+/*
+ * U T I L I T Y R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Monotonic Time
+ *
+ */
+static time_t dns_now(void) {
+ /* XXX: Assumes sizeof (time_t) <= sizeof (sig_atomic_t) */
+ static volatile sig_atomic_t last, tick;
+ volatile sig_atomic_t tmp_last, tmp_tick;
+ time_t now;
+
+ time(&now);
+
+ tmp_last = last;
+
+ if (now > tmp_last) {
+ tmp_tick = tick;
+ tmp_tick += now - tmp_last;
+ tick = tmp_tick;
+ }
+
+ last = now;
+
+ return tick;
+} /* dns_now() */
+
+static time_t dns_elapsed(time_t from) {
+ time_t now = dns_now();
+
+ return (now > from)? now - from : 0;
+} /* dns_elpased() */
+
+
+static size_t dns_af_len(int af) {
+ static const size_t table[AF_MAX] = {
+ [AF_INET6] = sizeof (struct sockaddr_in6),
+ [AF_INET] = sizeof (struct sockaddr_in),
+#if defined(AF_UNIX) && !defined(_WIN32)
+ [AF_UNIX] = sizeof (struct sockaddr_un),
+#endif
+ };
+
+ return table[af];
+} /* dns_af_len() */
+
+#define dns_sa_len(sa) dns_af_len(dns_sa_family(sa))
+
+
+#define DNS_SA_NOPORT &dns_sa_noport
+static unsigned short dns_sa_noport;
+
+unsigned short *dns_sa_port(int af, void *sa) {
+ switch (af) {
+ case AF_INET6:
+ return &((struct sockaddr_in6 *)sa)->sin6_port;
+ case AF_INET:
+ return &((struct sockaddr_in *)sa)->sin_port;
+ default:
+ return DNS_SA_NOPORT;
+ }
+} /* dns_sa_port() */
+
+
+void *dns_sa_addr(int af, void *sa) {
+ switch (af) {
+ case AF_INET6:
+ return &((struct sockaddr_in6 *)sa)->sin6_addr;
+ case AF_INET:
+ return &((struct sockaddr_in *)sa)->sin_addr;
+ default:
+ return 0;
+ }
+} /* dns_sa_addr() */
+
+
+#if _WIN32
+static int dns_inet_pton(int af, const void *src, void *dst) {
+ union { struct sockaddr_in sin; struct sockaddr_in6 sin6; } u;
+
+ u.sin.sin_family = af;
+
+ if (0 != WSAStringToAddressA((void *)src, af, (void *)0, (struct sockaddr *)&u, &(int){ sizeof u }))
+ return -1;
+
+ switch (af) {
+ case AF_INET6:
+ *(struct in6_addr *)dst = u.sin6.sin6_addr;
+
+ return 1;
+ case AF_INET:
+ *(struct in_addr *)dst = u.sin.sin_addr;
+
+ return 1;
+ default:
+ return 0;
+ }
+} /* dns_inet_pton() */
+
+const char *dns_inet_ntop(int af, const void *src, void *dst, unsigned long lim) {
+ union { struct sockaddr_in sin; struct sockaddr_in6 sin6; } u;
+
+ /* NOTE: WSAAddressToString will print .sin_port unless zeroed. */
+ memset(&u, 0, sizeof u);
+
+ u.sin.sin_family = af;
+
+ switch (af) {
+ case AF_INET6:
+ u.sin6.sin6_addr = *(struct in6_addr *)src;
+ break;
+ case AF_INET:
+ u.sin.sin_addr = *(struct in_addr *)src;
+
+ break;
+ default:
+ return 0;
+ }
+
+ if (0 != WSAAddressToStringA((struct sockaddr *)&u, dns_sa_len(&u), (void *)0, dst, &lim))
+ return 0;
+
+ return dst;
+} /* dns_inet_ntop() */
+#endif
+
+
+size_t dns_strlcpy(char *dst, const char *src, size_t lim) {
+ char *d = dst;
+ char *e = &dst[lim];
+ const char *s = src;
+
+ if (d < e) {
+ do {
+ if ('\0' == (*d++ = *s++))
+ return s - src - 1;
+ } while (d < e);
+
+ d[-1] = '\0';
+ }
+
+ while (*s++ != '\0')
+ ;;
+
+ return s - src - 1;
+} /* dns_strlcpy() */
+
+
+size_t dns_strlcat(char *dst, const char *src, size_t lim) {
+ char *d = memchr(dst, '\0', lim);
+ char *e = &dst[lim];
+ const char *s = src;
+ const char *p;
+
+ if (d && d < e) {
+ do {
+ if ('\0' == (*d++ = *s++))
+ return d - dst - 1;
+ } while (d < e);
+
+ d[-1] = '\0';
+ }
+
+ p = s;
+
+ while (*s++ != '\0')
+ ;;
+
+ return lim + (s - p - 1);
+} /* dns_strlcat() */
+
+
+#if _WIN32
+
+static char *dns_strsep(char **sp, const char *delim) {
+ char *p;
+
+ if (!(p = *sp))
+ return 0;
+
+ *sp += strcspn(p, delim);
+
+ if (**sp != '\0') {
+ **sp = '\0';
+ ++*sp;
+ } else
+ *sp = NULL;
+
+ return p;
+} /* dns_strsep() */
+
+#else
+#define dns_strsep(...) strsep(__VA_ARGS__)
+#endif
+
+
+#if _WIN32
+#define strcasecmp(...) _stricmp(__VA_ARGS__)
+#define strncasecmp(...) _strnicmp(__VA_ARGS__)
+#endif
+
+
+static int dns_poll(int fd, short events, int timeout) {
+ fd_set rset, wset;
+
+ if (!events)
+ return 0;
+
+ assert(fd >= 0 && fd < FD_SETSIZE);
+
+ FD_ZERO(&rset);
+ FD_ZERO(&wset);
+
+ if (events & DNS_POLLIN)
+ FD_SET(fd, &rset);
+
+ if (events & DNS_POLLOUT)
+ FD_SET(fd, &wset);
+
+ select(fd + 1, &rset, &wset, 0, (timeout >= 0)? &(struct timeval){ timeout, 0 } : NULL);
+
+ return 0;
+} /* dns_poll() */
+
+
+/*
+ * P A C K E T R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+unsigned dns_p_count(struct dns_packet *P, enum dns_section section) {
+ unsigned count;
+
+ switch (section) {
+ case DNS_S_QD:
+ return ntohs(dns_header(P)->qdcount);
+ case DNS_S_AN:
+ return ntohs(dns_header(P)->ancount);
+ case DNS_S_NS:
+ return ntohs(dns_header(P)->nscount);
+ case DNS_S_AR:
+ return ntohs(dns_header(P)->arcount);
+ default:
+ count = 0;
+
+ if (section & DNS_S_QD)
+ count += ntohs(dns_header(P)->qdcount);
+ if (section & DNS_S_AN)
+ count += ntohs(dns_header(P)->ancount);
+ if (section & DNS_S_NS)
+ count += ntohs(dns_header(P)->nscount);
+ if (section & DNS_S_AR)
+ count += ntohs(dns_header(P)->arcount);
+
+ return count;
+ }
+} /* dns_p_count() */
+
+
+struct dns_packet *dns_p_init(struct dns_packet *P, size_t size) {
+ if (!P)
+ return 0;
+
+ assert(size >= offsetof(struct dns_packet, data) + 12);
+
+ memset(P, 0, sizeof *P);
+ P->size = size - offsetof(struct dns_packet, data);
+ P->end = 12;
+
+ memset(P->data, '\0', 12);
+
+ return P;
+} /* dns_p_init() */
+
+
+static unsigned short dns_p_qend(struct dns_packet *P) {
+ unsigned short qend = 12;
+ unsigned i, count = dns_p_count(P, DNS_S_QD);
+
+ for (i = 0; i < count && qend < P->end; i++) {
+ if (P->end == (qend = dns_d_skip(qend, P)))
+ goto invalid;
+
+ if (P->end - qend < 4)
+ goto invalid;
+
+ qend += 4;
+ }
+
+ return MIN(qend, P->end);
+invalid:
+ return P->end;
+} /* dns_p_qend() */
+
+
+struct dns_packet *dns_p_make(size_t len, int *error) {
+ struct dns_packet *P;
+ size_t size = dns_p_calcsize(len);
+
+ if (!(P = dns_p_init(malloc(size), size)))
+ *error = dns_syerr();
+
+ return P;
+} /* dns_p_make() */
+
+
+int dns_p_grow(struct dns_packet **P) {
+ struct dns_packet *tmp;
+ size_t size;
+ int error;
+
+ if (!*P) {
+ if (!(*P = dns_p_make(DNS_P_QBUFSIZ, &error)))
+ return error;
+
+ return 0;
+ }
+
+ size = dns_p_sizeof(*P);
+ size |= size >> 1;
+ size |= size >> 2;
+ size |= size >> 4;
+ size |= size >> 8;
+ size++;
+
+ if (size > 65536)
+ return DNS_ENOBUFS;
+
+ if (!(tmp = realloc(*P, dns_p_calcsize(size))))
+ return dns_syerr();
+
+ tmp->size = size;
+ *P = tmp;
+
+ return 0;
+} /* dns_p_grow() */
+
+
+struct dns_packet *dns_p_copy(struct dns_packet *P, const struct dns_packet *P0) {
+ if (!P)
+ return 0;
+
+ P->end = MIN(P->size, P0->end);
+
+ memcpy(P->data, P0->data, P->end);
+
+ return P;
+} /* dns_p_copy() */
+
+
+struct dns_packet *dns_p_merge(struct dns_packet *A, enum dns_section Amask, struct dns_packet *B, enum dns_section Bmask, int *error_) {
+ size_t bufsiz = MIN(65535, ((A)? A->end : 0) + ((B)? B->end : 0));
+ struct dns_packet *M;
+ enum dns_section section;
+ struct dns_rr rr, mr;
+ int error, copy;
+
+ if (!A && B) {
+ A = B;
+ Amask = Bmask;
+ B = 0;
+ }
+
+merge:
+ if (!(M = dns_p_make(bufsiz, &error)))
+ goto error;
+
+ for (section = DNS_S_QD; (DNS_S_ALL & section); section <<= 1) {
+ if (A && (section & Amask)) {
+ dns_rr_foreach(&rr, A, .section = section) {
+ if ((error = dns_rr_copy(M, &rr, A)))
+ goto error;
+ }
+ }
+
+ if (B && (section & Bmask)) {
+ dns_rr_foreach(&rr, B, .section = section) {
+ copy = 1;
+
+ dns_rr_foreach(&mr, M, .type = rr.type, .section = DNS_S_ALL) {
+ if (!(copy = dns_rr_cmp(&rr, B, &mr, M)))
+ break;
+ }
+
+ if (copy && (error = dns_rr_copy(M, &rr, B)))
+ goto error;
+ }
+ }
+ }
+
+ return M;
+error:
+ free(M); M = 0;
+
+ if (error == DNS_ENOBUFS && bufsiz < 65535) {
+ bufsiz = MIN(65535, bufsiz * 2);
+
+ goto merge;
+ }
+
+ *error_ = error;
+
+ return 0;
+} /* dns_p_merge() */
+
+
+static unsigned short dns_l_skip(unsigned short, const unsigned char *, size_t);
+
+void dns_p_dictadd(struct dns_packet *P, unsigned short dn) {
+ unsigned short lp, lptr, i;
+
+ lp = dn;
+
+ while (lp < P->end) {
+ if (0xc0 == (0xc0 & P->data[lp]) && P->end - lp >= 2 && lp != dn) {
+ lptr = ((0x3f & P->data[lp + 0]) << 8)
+ | ((0xff & P->data[lp + 1]) << 0);
+
+ for (i = 0; i < lengthof(P->dict) && P->dict[i]; i++) {
+ if (P->dict[i] == lptr) {
+ P->dict[i] = dn;
+
+ return;
+ }
+ }
+ }
+
+ lp = dns_l_skip(lp, P->data, P->end);
+ }
+
+ for (i = 0; i < lengthof(P->dict); i++) {
+ if (!P->dict[i]) {
+ P->dict[i] = dn;
+
+ break;
+ }
+ }
+} /* dns_p_dictadd() */
+
+
+int dns_p_push(struct dns_packet *P, enum dns_section section, const void *dn, size_t dnlen, enum dns_type type, enum dns_class class, unsigned ttl, const void *any) {
+ size_t end = P->end;
+ int error;
+
+ if ((error = dns_d_push(P, dn, dnlen)))
+ goto error;
+
+ if (P->size - P->end < 4)
+ goto nobufs;
+
+ P->data[P->end++] = 0xff & (type >> 8);
+ P->data[P->end++] = 0xff & (type >> 0);
+
+ P->data[P->end++] = 0xff & (class >> 8);
+ P->data[P->end++] = 0xff & (class >> 0);
+
+ if (section == DNS_S_QD)
+ goto update;
+
+ if (P->size - P->end < 6)
+ goto nobufs;
+
+ P->data[P->end++] = 0x7f & (ttl >> 24);
+ P->data[P->end++] = 0xff & (ttl >> 16);
+ P->data[P->end++] = 0xff & (ttl >> 8);
+ P->data[P->end++] = 0xff & (ttl >> 0);
+
+ if ((error = dns_any_push(P, (union dns_any *)any, type)))
+ goto error;
+
+update:
+ switch (section) {
+ case DNS_S_QD:
+ if (dns_p_count(P, DNS_S_AN|DNS_S_NS|DNS_S_AR))
+ goto order;
+
+ if (!P->qd.base && (error = dns_p_study(P)))
+ goto error;
+
+ dns_header(P)->qdcount = htons(ntohs(dns_header(P)->qdcount) + 1);
+
+ P->qd.end = P->end;
+ P->an.base = P->end;
+ P->an.end = P->end;
+ P->ns.base = P->end;
+ P->ns.end = P->end;
+ P->ar.base = P->end;
+ P->ar.end = P->end;
+
+ break;
+ case DNS_S_AN:
+ if (dns_p_count(P, DNS_S_NS|DNS_S_AR))
+ goto order;
+
+ if (!P->an.base && (error = dns_p_study(P)))
+ goto error;
+
+ dns_header(P)->ancount = htons(ntohs(dns_header(P)->ancount) + 1);
+
+ P->an.end = P->end;
+ P->ns.base = P->end;
+ P->ns.end = P->end;
+ P->ar.base = P->end;
+ P->ar.end = P->end;
+
+ break;
+ case DNS_S_NS:
+ if (dns_p_count(P, DNS_S_AR))
+ goto order;
+
+ if (!P->ns.base && (error = dns_p_study(P)))
+ goto error;
+
+ dns_header(P)->nscount = htons(ntohs(dns_header(P)->nscount) + 1);
+
+ P->ns.end = P->end;
+ P->ar.base = P->end;
+ P->ar.end = P->end;
+
+ break;
+ case DNS_S_AR:
+ if (!P->ar.base && (error = dns_p_study(P)))
+ goto error;
+
+ dns_header(P)->arcount = htons(ntohs(dns_header(P)->arcount) + 1);
+
+ P->ar.end = P->end;
+
+ break;
+ default:
+ error = DNS_ESECTION;
+
+ goto error;
+ } /* switch() */
+
+ return 0;
+nobufs:
+ error = DNS_ENOBUFS;
+
+ goto error;
+order:
+ error = DNS_EORDER;
+
+ goto error;
+error:
+ P->end = end;
+
+ return error;
+} /* dns_p_push() */
+
+
+static void dns_p_dump3(struct dns_packet *P, struct dns_rr_i *I, FILE *fp) {
+ enum dns_section section;
+ struct dns_rr rr;
+ int error;
+ union dns_any any;
+ char pretty[sizeof any * 2];
+ size_t len;
+
+ fputs(";; [HEADER]\n", fp);
+ fprintf(fp, ";; qr : %s(%d)\n", (dns_header(P)->qr)? "RESPONSE" : "QUERY", dns_header(P)->qr);
+ fprintf(fp, ";; opcode : %s(%d)\n", dns_stropcode(dns_header(P)->opcode), dns_header(P)->opcode);
+ fprintf(fp, ";; aa : %s(%d)\n", (dns_header(P)->aa)? "AUTHORITATIVE" : "NON-AUTHORITATIVE", dns_header(P)->aa);
+ fprintf(fp, ";; tc : %s(%d)\n", (dns_header(P)->tc)? "TRUNCATED" : "NOT-TRUNCATED", dns_header(P)->tc);
+ fprintf(fp, ";; rd : %s(%d)\n", (dns_header(P)->rd)? "RECURSION-DESIRED" : "RECURSION-NOT-DESIRED", dns_header(P)->rd);
+ fprintf(fp, ";; ra : %s(%d)\n", (dns_header(P)->ra)? "RECURSION-ALLOWED" : "RECURSION-NOT-ALLOWED", dns_header(P)->ra);
+ fprintf(fp, ";; rcode : %s(%d)\n", dns_strrcode(dns_header(P)->rcode), dns_header(P)->rcode);
+
+ section = 0;
+
+ while (dns_rr_grep(&rr, 1, I, P, &error)) {
+ if (section != rr.section)
+ fprintf(fp, "\n;; [%s:%d]\n", dns_strsection(rr.section), dns_p_count(P, rr.section));
+
+ if ((len = dns_rr_print(pretty, sizeof pretty, &rr, P, &error)))
+ fprintf(fp, "%s\n", pretty);
+
+ section = rr.section;
+ }
+} /* dns_p_dump3() */
+
+
+void dns_p_dump(struct dns_packet *P, FILE *fp) {
+ dns_p_dump3(P, dns_rr_i_new(P, .section = 0), fp);
+} /* dns_p_dump() */
+
+
+static void dns_s_unstudy(struct dns_s_memo *m)
+ { m->base = 0; m->end = 0; }
+
+static void dns_p_unstudy(struct dns_packet *P) {
+ dns_s_unstudy(&P->qd);
+ dns_s_unstudy(&P->an);
+ dns_s_unstudy(&P->ns);
+ dns_s_unstudy(&P->ar);
+} /* dns_p_unstudy() */
+
+static int dns_s_study(struct dns_s_memo *m, enum dns_section section, unsigned base, struct dns_packet *P) {
+ unsigned short count, rp;
+
+ count = dns_p_count(P, section);
+
+ for (rp = base; count && rp < P->end; count--)
+ rp = dns_rr_skip(rp, P);
+
+ m->base = base;
+ m->end = rp;
+
+ return 0;
+} /* dns_s_study() */
+
+int dns_p_study(struct dns_packet *P) {
+ int error;
+
+ if ((error = dns_s_study(&P->qd, DNS_S_QD, 12, P)))
+ goto error;
+
+ if ((error = dns_s_study(&P->an, DNS_S_AN, P->qd.end, P)))
+ goto error;
+
+ if ((error = dns_s_study(&P->ns, DNS_S_NS, P->an.end, P)))
+ goto error;
+
+ if ((error = dns_s_study(&P->ar, DNS_S_AR, P->ns.end, P)))
+ goto error;
+
+ return 0;
+error:
+ dns_p_unstudy(P);
+
+ return error;
+} /* dns_p_study() */
+
+
+/*
+ * D O M A I N N A M E R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+#ifndef DNS_D_MAXPTRS
+#define DNS_D_MAXPTRS 127 /* Arbitrary; possible, valid depth is something like packet size / 2 + fudge. */
+#endif
+
+static size_t dns_l_expand(unsigned char *dst, size_t lim, unsigned short src, unsigned short *nxt, const unsigned char *data, size_t end) {
+ unsigned short len;
+ unsigned nptrs = 0;
+
+retry:
+ if (src >= end)
+ goto invalid;
+
+ switch (0x03 & (data[src] >> 6)) {
+ case 0x00:
+ len = (0x3f & (data[src++]));
+
+ if (end - src < len)
+ goto invalid;
+
+ if (lim > 0) {
+ memcpy(dst, &data[src], MIN(lim, len));
+
+ dst[MIN(lim - 1, len)] = '\0';
+ }
+
+ *nxt = src + len;
+
+ return len;
+ case 0x01:
+ goto invalid;
+ case 0x02:
+ goto invalid;
+ case 0x03:
+ if (++nptrs > DNS_D_MAXPTRS)
+ goto invalid;
+
+ if (end - src < 2)
+ goto invalid;
+
+ src = ((0x3f & data[src + 0]) << 8)
+ | ((0xff & data[src + 1]) << 0);
+
+ goto retry;
+ } /* switch() */
+
+ /* NOT REACHED */
+invalid:
+ *nxt = end;
+
+ return 0;
+} /* dns_l_expand() */
+
+
+static unsigned short dns_l_skip(unsigned short src, const unsigned char *data, size_t end) {
+ unsigned short len;
+
+ if (src >= end)
+ goto invalid;
+
+ switch (0x03 & (data[src] >> 6)) {
+ case 0x00:
+ len = (0x3f & (data[src++]));
+
+ if (end - src < len)
+ goto invalid;
+
+ return (len)? src + len : end;
+ case 0x01:
+ goto invalid;
+ case 0x02:
+ goto invalid;
+ case 0x03:
+ return end;
+ } /* switch() */
+
+ /* NOT REACHED */
+invalid:
+ return end;
+} /* dns_l_skip() */
+
+
+size_t dns_d_trim(void *dst_, size_t lim, const void *src_, size_t len, int flags) {
+ unsigned char *dst = dst_;
+ const unsigned char *src = src_;
+ size_t dp = 0, sp = 0;
+ int lc;
+
+ /* trim any leading dot(s) */
+ while (sp < len && src[sp] == '.')
+ sp++;
+
+ for (lc = 0; sp < len; lc = src[sp]) {
+ if (dp < lim)
+ dst[dp] = src[sp];
+
+ sp++;
+ dp++;
+
+ /* trim extra dot(s) */
+ while (sp < len && src[sp] == '.')
+ sp++;
+ }
+
+ if ((flags & DNS_D_ANCHOR) && lc != '.') {
+ if (dp < lim)
+ dst[dp] = '.';
+
+ dp++;
+ }
+
+ if (lim > 0)
+ dst[MIN(dp, lim - 1)] = '\0';
+
+ return dp;
+} /* dns_d_trim() */
+
+
+char *dns_d_init(void *dst, size_t lim, const void *src, size_t len, int flags) {
+ if (flags & DNS_D_TRIM) {
+ dns_d_trim(dst, lim, src, len, flags);
+ } if (flags & DNS_D_ANCHOR) {
+ dns_d_anchor(dst, lim, src, len);
+ } else {
+ memmove(dst, src, MIN(lim, len));
+
+ if (lim > 0)
+ ((char *)dst)[MIN(len, lim - 1)] = '\0';
+ }
+
+ return dst;
+} /* dns_d_init() */
+
+
+size_t dns_d_anchor(void *dst, size_t lim, const void *src, size_t len) {
+ if (len == 0)
+ return 0;
+
+ memmove(dst, src, MIN(lim, len));
+
+ if (((const char *)src)[len - 1] != '.') {
+ if (len < lim)
+ ((char *)dst)[len] = '.';
+ len++;
+ }
+
+ if (lim > 0)
+ ((char *)dst)[MIN(lim - 1, len)] = '\0';
+
+ return len;
+} /* dns_d_anchor() */
+
+
+size_t dns_d_cleave(void *dst, size_t lim, const void *src, size_t len) {
+ const char *dot;
+
+ /* XXX: Skip any leading dot. Handles cleaving root ".". */
+ if (len == 0 || !(dot = memchr((const char *)src + 1, '.', len - 1)))
+ return 0;
+
+ len -= dot - (const char *)src;
+
+ /* XXX: Unless root, skip the label's trailing dot. */
+ if (len > 1) {
+ src = ++dot;
+ len--;
+ } else
+ src = dot;
+
+ memmove(dst, src, MIN(lim, len));
+
+ if (lim > 0)
+ ((char *)dst)[MIN(lim - 1, len)] = '\0';
+
+ return len;
+} /* dns_d_cleave() */
+
+
+size_t dns_d_comp(void *dst_, size_t lim, const void *src_, size_t len, struct dns_packet *P, int *error __UNUSED__) {
+ struct { unsigned char *b; size_t p, x; } dst, src;
+ unsigned char ch = '.';
+
+ dst.b = dst_;
+ dst.p = 0;
+ dst.x = 1;
+
+ src.b = (unsigned char *)src_;
+ src.p = 0;
+ src.x = 0;
+
+ while (src.x < len) {
+ ch = src.b[src.x];
+
+ if (ch == '.') {
+ if (dst.p < lim)
+ dst.b[dst.p] = (0x3f & (src.x - src.p));
+
+ dst.p = dst.x++;
+ src.p = ++src.x;
+ } else {
+ if (dst.x < lim)
+ dst.b[dst.x] = ch;
+
+ dst.x++;
+ src.x++;
+ }
+ } /* while() */
+
+ if (src.x > src.p) {
+ if (dst.p < lim)
+ dst.b[dst.p] = (0x3f & (src.x - src.p));
+
+ dst.p = dst.x;
+ }
+
+ if (dst.p > 1) {
+ if (dst.p < lim)
+ dst.b[dst.p] = 0x00;
+
+ dst.p++;
+ }
+
+#if 1
+ if (dst.p < lim) {
+ struct { unsigned char label[DNS_D_MAXLABEL + 1]; size_t len; unsigned short p, x, y; } a, b;
+ unsigned i;
+
+ a.p = 0;
+
+ while ((a.len = dns_l_expand(a.label, sizeof a.label, a.p, &a.x, dst.b, lim))) {
+ for (i = 0; i < lengthof(P->dict) && P->dict[i]; i++) {
+ b.p = P->dict[i];
+
+ while ((b.len = dns_l_expand(b.label, sizeof b.label, b.p, &b.x, P->data, P->end))) {
+ a.y = a.x;
+ b.y = b.x;
+
+ while (a.len && b.len && 0 == strcasecmp((char *)a.label, (char *)b.label)) {
+ a.len = dns_l_expand(a.label, sizeof a.label, a.y, &a.y, dst.b, lim);
+ b.len = dns_l_expand(b.label, sizeof b.label, b.y, &b.y, P->data, P->end);
+ }
+
+ if (a.len == 0 && b.len == 0 && b.p <= 0x3fff) {
+ dst.b[a.p++] = 0xc0
+ | (0x3f & (b.p >> 8));
+ dst.b[a.p++] = (0xff & (b.p >> 0));
+
+ return a.p;
+ }
+
+ b.p = b.x;
+ } /* while() */
+ } /* for() */
+
+ a.p = a.x;
+ } /* while() */
+ } /* if () */
+#endif
+
+ return dst.p;
+} /* dns_d_comp() */
+
+
+unsigned short dns_d_skip(unsigned short src, struct dns_packet *P) {
+ unsigned short len;
+
+ while (src < P->end) {
+ switch (0x03 & (P->data[src] >> 6)) {
+ case 0x00: /* FOLLOWS */
+ len = (0x3f & P->data[src++]);
+
+ if (0 == len) {
+/* success ==> */ return src;
+ } else if (P->end - src > len) {
+ src += len;
+
+ break;
+ } else
+ goto invalid;
+
+ /* NOT REACHED */
+ case 0x01: /* RESERVED */
+ goto invalid;
+ case 0x02: /* RESERVED */
+ goto invalid;
+ case 0x03: /* POINTER */
+ if (P->end - src < 2)
+ goto invalid;
+
+ src += 2;
+
+/* success ==> */ return src;
+ } /* switch() */
+ } /* while() */
+
+invalid:
+//assert(0);
+ return P->end;
+} /* dns_d_skip() */
+
+
+#include <stdio.h>
+
+size_t dns_d_expand(void *dst, size_t lim, unsigned short src, struct dns_packet *P, int *error) {
+ size_t dstp = 0;
+ unsigned nptrs = 0;
+ unsigned char len;
+
+ while (src < P->end) {
+ switch ((0x03 & (P->data[src] >> 6))) {
+ case 0x00: /* FOLLOWS */
+ len = (0x3f & P->data[src]);
+
+ if (0 == len) {
+ if (dstp == 0) {
+ if (dstp < lim)
+ ((unsigned char *)dst)[dstp] = '.';
+
+ dstp++;
+ }
+
+ /* NUL terminate */
+ if (lim > 0)
+ ((unsigned char *)dst)[MIN(dstp, lim - 1)] = '\0';
+
+/* success ==> */ return dstp;
+ }
+
+ src++;
+
+ if (P->end - src < len)
+ goto toolong;
+
+ if (dstp < lim)
+ memcpy(&((unsigned char *)dst)[dstp], &P->data[src], MIN(len, lim - dstp));
+
+ src += len;
+ dstp += len;
+
+ if (dstp < lim)
+ ((unsigned char *)dst)[dstp] = '.';
+
+ dstp++;
+
+ nptrs = 0;
+
+ continue;
+ case 0x01: /* RESERVED */
+ goto reserved;
+ case 0x02: /* RESERVED */
+ goto reserved;
+ case 0x03: /* POINTER */
+ if (++nptrs > DNS_D_MAXPTRS)
+ goto toolong;
+
+ if (P->end - src < 2)
+ goto toolong;
+
+ src = ((0x3f & P->data[src + 0]) << 8)
+ | ((0xff & P->data[src + 1]) << 0);
+
+ continue;
+ } /* switch() */
+ } /* while() */
+
+toolong:
+ *error = DNS_EILLEGAL;
+
+ if (lim > 0)
+ ((unsigned char *)dst)[MIN(dstp, lim - 1)] = '\0';
+
+ return 0;
+reserved:
+ *error = DNS_EILLEGAL;
+
+ if (lim > 0)
+ ((unsigned char *)dst)[MIN(dstp, lim - 1)] = '\0';
+
+ return 0;
+} /* dns_d_expand() */
+
+
+int dns_d_push(struct dns_packet *P, const void *dn, size_t len) {
+ size_t lim = P->size - P->end;
+ unsigned dp = P->end;
+ int error;
+
+ len = dns_d_comp(&P->data[dp], lim, dn, len, P, &error);
+
+ if (len == 0)
+ return error;
+ if (len > lim)
+ return DNS_ENOBUFS;
+
+ P->end += len;
+
+ dns_p_dictadd(P, dp);
+
+ return 0;
+} /* dns_d_push() */
+
+
+size_t dns_d_cname(void *dst, size_t lim, const void *dn, size_t len, struct dns_packet *P, int *error_) {
+ char host[DNS_D_MAXNAME + 1];
+ struct dns_rr_i i;
+ struct dns_rr rr;
+ unsigned depth;
+ int error;
+
+ if (sizeof host <= dns_d_anchor(host, sizeof host, dn, len))
+ { error = ENAMETOOLONG; goto error; }
+
+ for (depth = 0; depth < 7; depth++) {
+ dns_rr_i_init(memset(&i, 0, sizeof i), P);
+
+ i.section = DNS_S_ALL & ~DNS_S_QD;
+ i.name = host;
+ i.type = DNS_T_CNAME;
+
+ if (!dns_rr_grep(&rr, 1, &i, P, &error))
+ break;
+
+ if ((error = dns_cname_parse((struct dns_cname *)host, &rr, P)))
+ goto error;
+ }
+
+ return dns_strlcpy(dst, host, lim);
+error:
+ *error_ = error;
+
+ return 0;
+} /* dns_d_cname() */
+
+
+/*
+ * R E S O U R C E R E C O R D R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+int dns_rr_copy(struct dns_packet *P, struct dns_rr *rr, struct dns_packet *Q) {
+ unsigned char dn[DNS_D_MAXNAME + 1];
+ union dns_any any;
+ size_t len;
+ int error;
+
+ if (!(len = dns_d_expand(dn, sizeof dn, rr->dn.p, Q, &error)))
+ return error;
+ else if (len >= sizeof dn)
+ return DNS_EILLEGAL;
+
+ if (rr->section != DNS_S_QD && (error = dns_any_parse(dns_any_init(&any, sizeof any), rr, Q)))
+ return error;
+
+ return dns_p_push(P, rr->section, dn, len, rr->type, rr->class, rr->ttl, &any);
+} /* dns_rr_copy() */
+
+
+int dns_rr_parse(struct dns_rr *rr, unsigned short src, struct dns_packet *P) {
+ unsigned short p = src;
+
+ if (src >= P->end)
+ goto invalid;
+
+ rr->dn.p = p;
+ rr->dn.len = (p = dns_d_skip(p, P)) - rr->dn.p;
+
+ if (P->end - p < 4)
+ goto invalid;
+
+ rr->type = ((0xff & P->data[p + 0]) << 8)
+ | ((0xff & P->data[p + 1]) << 0);
+
+ rr->class = ((0xff & P->data[p + 2]) << 8)
+ | ((0xff & P->data[p + 3]) << 0);
+
+ p += 4;
+
+ if (src < dns_p_qend(P)) {
+ rr->section = DNS_S_QUESTION;
+
+ rr->ttl = 0;
+ rr->rd.p = 0;
+ rr->rd.len = 0;
+
+ return 0;
+ }
+
+ if (P->end - p < 4)
+ goto invalid;
+
+ rr->ttl = ((0x7f & P->data[p + 0]) << 24)
+ | ((0xff & P->data[p + 1]) << 16)
+ | ((0xff & P->data[p + 2]) << 8)
+ | ((0xff & P->data[p + 3]) << 0);
+
+ p += 4;
+
+ if (P->end - p < 2)
+ goto invalid;
+
+ rr->rd.len = ((0xff & P->data[p + 0]) << 8)
+ | ((0xff & P->data[p + 1]) << 0);
+ rr->rd.p = p + 2;
+
+ p += 2;
+
+ if (P->end - p < rr->rd.len)
+ goto invalid;
+
+ return 0;
+invalid:
+//assert(0);
+ return DNS_EILLEGAL;
+} /* dns_rr_parse() */
+
+
+static unsigned short dns_rr_len(const unsigned short src, struct dns_packet *P) {
+ unsigned short rp, rdlen;
+
+ rp = dns_d_skip(src, P);
+
+ if (P->end - rp < 4)
+ return P->end - src;
+
+ rp += 4; /* TYPE, CLASS */
+
+ if (rp <= dns_p_qend(P))
+ return rp - src;
+
+ if (P->end - rp < 6)
+ return P->end - src;
+
+ rp += 6; /* TTL, RDLEN */
+
+ rdlen = ((0xff & P->data[rp - 2]) << 8)
+ | ((0xff & P->data[rp - 1]) << 0);
+
+ if (P->end - rp < rdlen)
+ return P->end - src;
+
+ rp += rdlen;
+
+ return rp - src;
+} /* dns_rr_len() */
+
+
+unsigned short dns_rr_skip(unsigned short src, struct dns_packet *P) {
+ return src + dns_rr_len(src, P);
+} /* dns_rr_skip() */
+
+
+static enum dns_section dns_rr_section(unsigned short src, struct dns_packet *P) {
+ enum dns_section section;
+ unsigned count, ind;
+ unsigned short rp;
+
+ if (src >= P->qd.base && src < P->qd.end)
+ return DNS_S_QD;
+ if (src >= P->an.base && src < P->an.end)
+ return DNS_S_AN;
+ if (src >= P->ns.base && src < P->ns.end)
+ return DNS_S_NS;
+ if (src >= P->ar.base && src < P->ar.end)
+ return DNS_S_AR;
+
+ /* NOTE: Possibly bad memoization. Try it the hard-way. */
+
+ for (rp = 12, ind = 0; rp < src && rp < P->end; ind++)
+ rp = dns_rr_skip(rp, P);
+
+ section = DNS_S_QD;
+ count = dns_p_count(P, section);
+
+ while (ind >= count && section <= DNS_S_AR) {
+ section <<= 1;
+ count += dns_p_count(P, section);
+ }
+
+ return DNS_S_ALL & section;
+} /* dns_rr_section() */
+
+
+static enum dns_type dns_rr_type(unsigned short src, struct dns_packet *P) {
+ struct dns_rr rr;
+ int error;
+
+ if ((error = dns_rr_parse(&rr, src, P)))
+ return 0;
+
+ return rr.type;
+} /* dns_rr_type() */
+
+
+int dns_rr_cmp(struct dns_rr *r0, struct dns_packet *P0, struct dns_rr *r1, struct dns_packet *P1) {
+ char host0[DNS_D_MAXNAME + 1], host1[DNS_D_MAXNAME + 1];
+ union dns_any any0, any1;
+ int cmp, error;
+ size_t len;
+
+ if ((cmp = r0->type - r1->type))
+ return cmp;
+
+ if ((cmp = r0->class - r1->class))
+ return cmp;
+
+ /*
+ * FIXME: Do label-by-label comparison to handle illegally long names?
+ */
+
+ if (!(len = dns_d_expand(host0, sizeof host0, r0->dn.p, P0, &error))
+ || len >= sizeof host0)
+ return -1;
+
+ if (!(len = dns_d_expand(host1, sizeof host1, r1->dn.p, P1, &error))
+ || len >= sizeof host1)
+ return 1;
+
+ if ((cmp = strcasecmp(host0, host1)))
+ return cmp;
+
+ if (DNS_S_QD & (r0->section | r1->section)) {
+ if (r0->section == r1->section)
+ return 0;
+
+ return (r0->section == DNS_S_QD)? -1 : 1;
+ }
+
+ if ((error = dns_any_parse(&any0, r0, P0)))
+ return -1;
+
+ if ((error = dns_any_parse(&any1, r1, P1)))
+ return 1;
+
+ return dns_any_cmp(&any0, r0->type, &any1, r1->type);
+} /* dns_rr_cmp() */
+
+
+static _Bool dns_rr_exists(struct dns_rr *rr0, struct dns_packet *P0, struct dns_packet *P1) {
+ struct dns_rr rr1;
+
+ dns_rr_foreach(&rr1, P1, .section = rr0->section, .type = rr0->type) {
+ if (0 == dns_rr_cmp(rr0, P0, &rr1, P1))
+ return 1;
+ }
+
+ return 0;
+} /* dns_rr_exists() */
+
+
+static unsigned short dns_rr_offset(struct dns_rr *rr) {
+ return rr->dn.p;
+} /* dns_rr_offset() */
+
+
+static _Bool dns_rr_i_match(struct dns_rr *rr, struct dns_rr_i *i, struct dns_packet *P) {
+ if (i->section && !(rr->section & i->section))
+ return 0;
+
+ if (i->type && rr->type != i->type && i->type != DNS_T_ALL)
+ return 0;
+
+ if (i->class && rr->class != i->class && i->class != DNS_C_ANY)
+ return 0;
+
+ if (i->name) {
+ char dn[DNS_D_MAXNAME + 1];
+ size_t len;
+ int error;
+
+ if (!(len = dns_d_expand(dn, sizeof dn, rr->dn.p, P, &error))
+ || len >= sizeof dn)
+ return 0;
+
+ if (0 != strcasecmp(dn, i->name))
+ return 0;
+ }
+
+ if (i->data && i->type && rr->section > DNS_S_QD) {
+ union dns_any rd;
+ int error;
+
+ if ((error = dns_any_parse(&rd, rr, P)))
+ return 0;
+
+ if (0 != dns_any_cmp(&rd, rr->type, i->data, i->type))
+ return 0;
+ }
+
+ return 1;
+} /* dns_rr_i_match() */
+
+
+static unsigned short dns_rr_i_start(struct dns_rr_i *i, struct dns_packet *P) {
+ unsigned short rp;
+ struct dns_rr r0, rr;
+ int error;
+
+ if ((i->section & DNS_S_QD) && P->qd.base)
+ rp = P->qd.base;
+ else if ((i->section & DNS_S_AN) && P->an.base)
+ rp = P->an.base;
+ else if ((i->section & DNS_S_NS) && P->ns.base)
+ rp = P->ns.base;
+ else if ((i->section & DNS_S_AR) && P->ar.base)
+ rp = P->ar.base;
+ else
+ rp = 12;
+
+ for (rp = 12; rp < P->end; rp = dns_rr_skip(rp, P)) {
+ if ((error = dns_rr_parse(&rr, rp, P)))
+ continue;
+
+ rr.section = dns_rr_section(rp, P);
+
+ if (!dns_rr_i_match(&rr, i, P))
+ continue;
+
+ r0 = rr;
+
+ goto lower;
+ }
+
+ return P->end;
+lower:
+ if (i->sort == &dns_rr_i_packet)
+ return dns_rr_offset(&r0);
+
+ while ((rp = dns_rr_skip(rp, P)) < P->end) {
+ if ((error = dns_rr_parse(&rr, rp, P)))
+ continue;
+
+ rr.section = dns_rr_section(rp, P);
+
+ if (!dns_rr_i_match(&rr, i, P))
+ continue;
+
+ if (i->sort(&rr, &r0, i, P) < 0)
+ r0 = rr;
+ }
+
+ return dns_rr_offset(&r0);
+} /* dns_rr_i_start() */
+
+
+static unsigned short dns_rr_i_skip(unsigned short rp, struct dns_rr_i *i, struct dns_packet *P) {
+ struct dns_rr r0, r1, rr;
+ int error;
+
+ if ((error = dns_rr_parse(&r0, rp, P)))
+ return P->end;
+
+ r0.section = dns_rr_section(rp, P);
+
+ rp = (i->sort == &dns_rr_i_packet)? dns_rr_skip(rp, P) : 12;
+
+ for (; rp < P->end; rp = dns_rr_skip(rp, P)) {
+ if ((error = dns_rr_parse(&rr, rp, P)))
+ continue;
+
+ rr.section = dns_rr_section(rp, P);
+
+ if (!dns_rr_i_match(&rr, i, P))
+ continue;
+
+ if (i->sort(&rr, &r0, i, P) <= 0)
+ continue;
+
+ r1 = rr;
+
+ goto lower;
+ }
+
+ return P->end;
+lower:
+ if (i->sort == &dns_rr_i_packet)
+ return dns_rr_offset(&r1);
+
+ while ((rp = dns_rr_skip(rp, P)) < P->end) {
+ if ((error = dns_rr_parse(&rr, rp, P)))
+ continue;
+
+ rr.section = dns_rr_section(rp, P);
+
+ if (!dns_rr_i_match(&rr, i, P))
+ continue;
+
+ if (i->sort(&rr, &r0, i, P) <= 0)
+ continue;
+
+ if (i->sort(&rr, &r1, i, P) >= 0)
+ continue;
+
+ r1 = rr;
+ }
+
+ return dns_rr_offset(&r1);
+} /* dns_rr_i_skip() */
+
+
+int dns_rr_i_packet(struct dns_rr *a, struct dns_rr *b, struct dns_rr_i *i __UNUSED__, struct dns_packet *P __UNUSED__) {
+ return (int)a->dn.p - (int)b->dn.p;
+} /* dns_rr_i_packet() */
+
+
+int dns_rr_i_order(struct dns_rr *a, struct dns_rr *b, struct dns_rr_i *i __UNUSED__, struct dns_packet *P) {
+ int cmp;
+
+ if ((cmp = a->section - b->section))
+ return cmp;
+
+ if (a->type != b->type)
+ return (int)a->dn.p - (int)b->dn.p;
+
+ return dns_rr_cmp(a, P, b, P);
+} /* dns_rr_i_order() */
+
+
+int dns_rr_i_shuffle(struct dns_rr *a, struct dns_rr *b, struct dns_rr_i *i, struct dns_packet *P __UNUSED__) {
+ int cmp;
+
+ while (!i->state.regs[0])
+ i->state.regs[0] = dns_random();
+
+ if ((cmp = a->section - b->section))
+ return cmp;
+
+ return dns_k_shuffle16(a->dn.p, i->state.regs[0]) - dns_k_shuffle16(b->dn.p, i->state.regs[0]);
+} /* dns_rr_i_shuffle() */
+
+
+struct dns_rr_i *dns_rr_i_init(struct dns_rr_i *i, struct dns_packet *P __UNUSED__) {
+ static const struct dns_rr_i i_initializer;
+
+ i->state = i_initializer.state;
+ i->saved = i->state;
+
+ return i;
+} /* dns_rr_i_init() */
+
+
+unsigned dns_rr_grep(struct dns_rr *rr, unsigned lim, struct dns_rr_i *i, struct dns_packet *P, int *error_) {
+ unsigned count = 0;
+ int error;
+
+ switch (i->state.exec) {
+ case 0:
+ if (!i->sort)
+ i->sort = &dns_rr_i_packet;
+
+ i->state.next = dns_rr_i_start(i, P);
+ i->state.exec++;
+
+ /* FALL THROUGH */
+ case 1:
+ while (count < lim && i->state.next < P->end) {
+ if ((error = dns_rr_parse(rr, i->state.next, P)))
+ goto error;
+
+ rr->section = dns_rr_section(i->state.next, P);
+
+ rr++;
+ count++;
+ i->state.count++;
+
+ i->state.next = dns_rr_i_skip(i->state.next, i, P);
+ } /* while() */
+
+ break;
+ } /* switch() */
+
+ return count;
+error:
+ *error_ = error;
+
+ return count;
+} /* dns_rr_grep() */
+
+
+static size_t dns__printchar(void *dst, size_t lim, size_t cp, unsigned char ch) {
+ if (cp < lim)
+ ((unsigned char *)dst)[cp] = ch;
+
+ return 1;
+} /* dns__printchar() */
+
+
+static size_t dns__printstring(void *dst, size_t lim, size_t cp, const void *src, size_t len) {
+ if (cp < lim)
+ memcpy(&((unsigned char *)dst)[cp], src, MIN(len, lim - cp));
+
+ return len;
+} /* dns__printstring() */
+
+#define dns__printstring5(a, b, c, d, e) dns__printstring((a), (b), (c), (d), (e))
+#define dns__printstring4(a, b, c, d) dns__printstring((a), (b), (c), (d), strlen((d)))
+#define dns__printstring(...) DNS_PP_CALL(DNS_PP_XPASTE(dns__printstring, DNS_PP_NARG(__VA_ARGS__)), __VA_ARGS__)
+
+
+static void dns__printnul(void *dst, size_t lim, size_t off) {
+ if (lim > 0)
+ ((unsigned char *)dst)[MIN(off, lim - 1)] = '\0';
+} /* dns__printnul() */
+
+
+static size_t dns__print10(void *dst, size_t lim, size_t off, unsigned n, unsigned pad) {
+ unsigned char tmp[32];
+ unsigned dp = off;
+ unsigned cp = 0;
+ unsigned d = 1000000000;
+ unsigned ch;
+
+ pad = MAX(1, pad);
+
+ while (d) {
+ if ((ch = n / d) || cp > 0) {
+ n -= ch * d;
+
+ tmp[cp] = '0' + ch;
+
+ cp++;
+ }
+
+ d /= 10;
+ }
+
+ while (cp < pad) {
+ dp += dns__printchar(dst, lim, dp, '0');
+ pad--;
+ }
+
+ dp += dns__printstring(dst, lim, dp, tmp, cp);
+
+ return dp - off;
+} /* dns__print10() */
+
+
+size_t dns_rr_print(void *dst, size_t lim, struct dns_rr *rr, struct dns_packet *P, int *error_) {
+ union dns_any any;
+ size_t cp, n, rdlen;
+ void *rd;
+ int error;
+
+ cp = 0;
+
+ if (rr->section == DNS_S_QD)
+ cp += dns__printchar(dst, lim, cp, ';');
+
+ if (!(n = dns_d_expand(&((unsigned char *)dst)[cp], (cp < lim)? lim - cp : 0, rr->dn.p, P, &error)))
+ goto error;
+
+ cp += n;
+
+ if (rr->section != DNS_S_QD) {
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, rr->ttl, 0);
+ }
+
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__printstring(dst, lim, cp, dns_strclass(rr->class), strlen(dns_strclass(rr->class)));
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__printstring(dst, lim, cp, dns_strtype(rr->type), strlen(dns_strtype(rr->type)));
+
+ if (rr->section == DNS_S_QD)
+ goto epilog;
+
+ cp += dns__printchar(dst, lim, cp, ' ');
+
+ if ((error = dns_any_parse(dns_any_init(&any, sizeof any), rr, P)))
+ goto error;
+
+ if (cp < lim) {
+ rd = &((unsigned char *)dst)[cp];
+ rdlen = lim - cp;
+ } else {
+ rd = 0;
+ rdlen = 0;
+ }
+
+ cp += dns_any_print(rd, rdlen, &any, rr->type);
+
+epilog:
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+error:
+ *error_ = error;
+
+ return 0;
+} /* dns_rr_print() */
+
+
+int dns_a_parse(struct dns_a *a, struct dns_rr *rr, struct dns_packet *P) {
+ unsigned long addr;
+
+ if (rr->rd.len != 4)
+ return DNS_EILLEGAL;
+
+ addr = ((0xff & P->data[rr->rd.p + 0]) << 24)
+ | ((0xff & P->data[rr->rd.p + 1]) << 16)
+ | ((0xff & P->data[rr->rd.p + 2]) << 8)
+ | ((0xff & P->data[rr->rd.p + 3]) << 0);
+
+ a->addr.s_addr = htonl(addr);
+
+ return 0;
+} /* dns_a_parse() */
+
+
+int dns_a_push(struct dns_packet *P, struct dns_a *a) {
+ unsigned long addr;
+
+ if (P->size - P->end < 6)
+ return DNS_ENOBUFS;
+
+ P->data[P->end++] = 0x00;
+ P->data[P->end++] = 0x04;
+
+ addr = ntohl(a->addr.s_addr);
+
+ P->data[P->end++] = 0xff & (addr >> 24);
+ P->data[P->end++] = 0xff & (addr >> 16);
+ P->data[P->end++] = 0xff & (addr >> 8);
+ P->data[P->end++] = 0xff & (addr >> 0);
+
+ return 0;
+} /* dns_a_push() */
+
+
+size_t dns_a_arpa(void *dst, size_t lim, const struct dns_a *a) {
+ unsigned long a4 = ntohl(a->addr.s_addr);
+ size_t cp = 0;
+ unsigned i;
+
+ for (i = 4; i > 0; i--) {
+ cp += dns__print10(dst, lim, cp, (0xff & a4), 0);
+ cp += dns__printchar(dst, lim, cp, '.');
+ a4 >>= 8;
+ }
+
+ cp += dns__printstring(dst, lim, cp, "in-addr.arpa.");
+
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+} /* dns_a_arpa() */
+
+
+int dns_a_cmp(const struct dns_a *a, const struct dns_a *b) {
+ if (ntohl(a->addr.s_addr) < ntohl(b->addr.s_addr))
+ return -1;
+ if (ntohl(a->addr.s_addr) > ntohl(b->addr.s_addr))
+ return 1;
+
+ return 0;
+} /* dns_a_cmp() */
+
+
+size_t dns_a_print(void *dst, size_t lim, struct dns_a *a) {
+ char addr[INET_ADDRSTRLEN + 1] = "0.0.0.0";
+ size_t len;
+
+ dns_inet_ntop(AF_INET, &a->addr, addr, sizeof addr);
+
+ dns__printnul(dst, lim, (len = dns__printstring(dst, lim, 0, addr)));
+
+ return len;
+} /* dns_a_print() */
+
+
+int dns_aaaa_parse(struct dns_aaaa *aaaa, struct dns_rr *rr, struct dns_packet *P) {
+ if (rr->rd.len != sizeof aaaa->addr.s6_addr)
+ return DNS_EILLEGAL;
+
+ memcpy(aaaa->addr.s6_addr, &P->data[rr->rd.p], sizeof aaaa->addr.s6_addr);
+
+ return 0;
+} /* dns_aaaa_parse() */
+
+
+int dns_aaaa_push(struct dns_packet *P, struct dns_aaaa *aaaa) {
+ if (P->size - P->end < 2 + sizeof aaaa->addr.s6_addr)
+ return DNS_ENOBUFS;
+
+ P->data[P->end++] = 0x00;
+ P->data[P->end++] = 0x10;
+
+ memcpy(&P->data[P->end], aaaa->addr.s6_addr, sizeof aaaa->addr.s6_addr);
+
+ P->end += sizeof aaaa->addr.s6_addr;
+
+ return 0;
+} /* dns_aaaa_push() */
+
+
+int dns_aaaa_cmp(const struct dns_aaaa *a, const struct dns_aaaa *b) {
+ unsigned i;
+ int cmp;
+
+ for (i = 0; i < lengthof(a->addr.s6_addr); i++) {
+ if ((cmp = (a->addr.s6_addr[i] - b->addr.s6_addr[i])))
+ return cmp;
+ }
+
+ return 0;
+} /* dns_aaaa_cmp() */
+
+
+size_t dns_aaaa_arpa(void *dst, size_t lim, const struct dns_aaaa *aaaa) {
+ static const unsigned char hex[16] = "0123456789abcdef";
+ size_t cp = 0;
+ unsigned nyble;
+ int i, j;
+
+ for (i = sizeof aaaa->addr.s6_addr - 1; i >= 0; i--) {
+ nyble = aaaa->addr.s6_addr[i];
+
+ for (j = 0; j < 2; j++) {
+ cp += dns__printchar(dst, lim, cp, hex[0x0f & nyble]);
+ cp += dns__printchar(dst, lim, cp, '.');
+ nyble >>= 4;
+ }
+ }
+
+ cp += dns__printstring(dst, lim, cp, "ip6.arpa.");
+
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+} /* dns_aaaa_arpa() */
+
+
+size_t dns_aaaa_print(void *dst, size_t lim, struct dns_aaaa *aaaa) {
+ char addr[INET6_ADDRSTRLEN + 1] = "::";
+ size_t len;
+
+ dns_inet_ntop(AF_INET6, &aaaa->addr, addr, sizeof addr);
+
+ dns__printnul(dst, lim, (len = dns__printstring(dst, lim, 0, addr)));
+
+ return len;
+} /* dns_aaaa_print() */
+
+
+int dns_mx_parse(struct dns_mx *mx, struct dns_rr *rr, struct dns_packet *P) {
+ size_t len;
+ int error;
+
+ if (rr->rd.len < 3)
+ return DNS_EILLEGAL;
+
+ mx->preference = (0xff00 & (P->data[rr->rd.p + 0] << 8))
+ | (0x00ff & (P->data[rr->rd.p + 1] << 0));
+
+ if (!(len = dns_d_expand(mx->host, sizeof mx->host, rr->rd.p + 2, P, &error)))
+ return error;
+ else if (len >= sizeof mx->host)
+ return DNS_EILLEGAL;
+
+ return 0;
+} /* dns_mx_parse() */
+
+
+int dns_mx_push(struct dns_packet *P, struct dns_mx *mx) {
+ size_t end, len;
+ int error;
+
+ if (P->size - P->end < 5)
+ return DNS_ENOBUFS;
+
+ end = P->end;
+ P->end += 2;
+
+ P->data[P->end++] = 0xff & (mx->preference >> 8);
+ P->data[P->end++] = 0xff & (mx->preference >> 0);
+
+ if ((error = dns_d_push(P, mx->host, strlen(mx->host))))
+ goto error;
+
+ len = P->end - end - 2;
+
+ P->data[end + 0] = 0xff & (len >> 8);
+ P->data[end + 1] = 0xff & (len >> 0);
+
+ return 0;
+error:
+ P->end = end;
+
+ return error;
+} /* dns_mx_push() */
+
+
+int dns_mx_cmp(const struct dns_mx *a, const struct dns_mx *b) {
+ int cmp;
+
+ if ((cmp = a->preference - b->preference))
+ return cmp;
+
+ return strcasecmp(a->host, b->host);
+} /* dns_mx_cmp() */
+
+
+size_t dns_mx_print(void *dst, size_t lim, struct dns_mx *mx) {
+ size_t cp = 0;
+
+ cp += dns__print10(dst, lim, cp, mx->preference, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__printstring(dst, lim, cp, mx->host, strlen(mx->host));
+
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+} /* dns_mx_print() */
+
+
+size_t dns_mx_cname(void *dst, size_t lim, struct dns_mx *mx) {
+ return dns_strlcpy(dst, mx->host, lim);
+} /* dns_mx_cname() */
+
+
+int dns_ns_parse(struct dns_ns *ns, struct dns_rr *rr, struct dns_packet *P) {
+ size_t len;
+ int error;
+
+ if (!(len = dns_d_expand(ns->host, sizeof ns->host, rr->rd.p, P, &error)))
+ return error;
+ else if (len >= sizeof ns->host)
+ return DNS_EILLEGAL;
+
+ return 0;
+} /* dns_ns_parse() */
+
+
+int dns_ns_push(struct dns_packet *P, struct dns_ns *ns) {
+ size_t end, len;
+ int error;
+
+ if (P->size - P->end < 3)
+ return DNS_ENOBUFS;
+
+ end = P->end;
+ P->end += 2;
+
+ if ((error = dns_d_push(P, ns->host, strlen(ns->host))))
+ goto error;
+
+ len = P->end - end - 2;
+
+ P->data[end + 0] = 0xff & (len >> 8);
+ P->data[end + 1] = 0xff & (len >> 0);
+
+ return 0;
+error:
+ P->end = end;
+
+ return error;
+} /* dns_ns_push() */
+
+
+int dns_ns_cmp(const struct dns_ns *a, const struct dns_ns *b) {
+ return strcasecmp(a->host, b->host);
+} /* dns_ns_cmp() */
+
+
+size_t dns_ns_print(void *dst, size_t lim, struct dns_ns *ns) {
+ size_t cp;
+
+ cp = dns__printstring(dst, lim, 0, ns->host, strlen(ns->host));
+
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+} /* dns_ns_print() */
+
+
+size_t dns_ns_cname(void *dst, size_t lim, struct dns_ns *ns) {
+ return dns_strlcpy(dst, ns->host, lim);
+} /* dns_ns_cname() */
+
+
+int dns_cname_parse(struct dns_cname *cname, struct dns_rr *rr, struct dns_packet *P) {
+ return dns_ns_parse((struct dns_ns *)cname, rr, P);
+} /* dns_cname_parse() */
+
+
+int dns_cname_push(struct dns_packet *P, struct dns_cname *cname) {
+ return dns_ns_push(P, (struct dns_ns *)cname);
+} /* dns_cname_push() */
+
+
+int dns_cname_cmp(const struct dns_cname *a, const struct dns_cname *b) {
+ return strcasecmp(a->host, b->host);
+} /* dns_cname_cmp() */
+
+
+size_t dns_cname_print(void *dst, size_t lim, struct dns_cname *cname) {
+ return dns_ns_print(dst, lim, (struct dns_ns *)cname);
+} /* dns_cname_print() */
+
+
+size_t dns_cname_cname(void *dst, size_t lim, struct dns_cname *cname) {
+ return dns_strlcpy(dst, cname->host, lim);
+} /* dns_cname_cname() */
+
+
+int dns_soa_parse(struct dns_soa *soa, struct dns_rr *rr, struct dns_packet *P) {
+ struct { void *dst; size_t lim; } dn[] =
+ { { soa->mname, sizeof soa->mname },
+ { soa->rname, sizeof soa->rname } };
+ unsigned *ts[] =
+ { &soa->serial, &soa->refresh, &soa->retry, &soa->expire, &soa->minimum };
+ unsigned short rp;
+ unsigned i, j, n;
+ int error;
+
+ /* MNAME / RNAME */
+ if ((rp = rr->rd.p) >= P->end)
+ return DNS_EILLEGAL;
+
+ for (i = 0; i < lengthof(dn); i++) {
+ if (!(n = dns_d_expand(dn[i].dst, dn[i].lim, rp, P, &error)))
+ return error;
+ else if (n >= dn[i].lim)
+ return DNS_EILLEGAL;
+
+ if ((rp = dns_d_skip(rp, P)) >= P->end)
+ return DNS_EILLEGAL;
+ }
+
+ /* SERIAL / REFRESH / RETRY / EXPIRE / MINIMUM */
+ for (i = 0; i < lengthof(ts); i++) {
+ for (j = 0; j < 4; j++, rp++) {
+ if (rp >= P->end)
+ return DNS_EILLEGAL;
+
+ *ts[i] <<= 8;
+ *ts[i] |= (0xff & P->data[rp]);
+ }
+ }
+
+ return 0;
+} /* dns_soa_parse() */
+
+
+int dns_soa_push(struct dns_packet *P, struct dns_soa *soa) {
+ void *dn[] = { soa->mname, soa->rname };
+ unsigned ts[] = { (0xffffffff & soa->serial),
+ (0x7fffffff & soa->refresh),
+ (0x7fffffff & soa->retry),
+ (0x7fffffff & soa->expire),
+ (0xffffffff & soa->minimum) };
+ unsigned i, j;
+ size_t end, len;
+ int error;
+
+ end = P->end;
+
+ if ((P->end += 2) >= P->size)
+ goto toolong;
+
+ /* MNAME / RNAME */
+ for (i = 0; i < lengthof(dn); i++) {
+ if ((error = dns_d_push(P, dn[i], strlen(dn[i]))))
+ goto error;
+ }
+
+ /* SERIAL / REFRESH / RETRY / EXPIRE / MINIMUM */
+ for (i = 0; i < lengthof(ts); i++) {
+ if ((P->end += 4) >= P->size)
+ goto toolong;
+
+ for (j = 1; j <= 4; j++) {
+ P->data[P->end - j] = (0xff & ts[i]);
+ ts[i] >>= 8;
+ }
+ }
+
+ len = P->end - end - 2;
+ P->data[end + 0] = (0xff & (len >> 8));
+ P->data[end + 1] = (0xff & (len >> 0));
+
+ return 0;
+toolong:
+ error = DNS_ENOBUFS;
+
+ /* FALL THROUGH */
+error:
+ P->end = end;
+
+ return error;
+} /* dns_soa_push() */
+
+
+int dns_soa_cmp(const struct dns_soa *a, const struct dns_soa *b) {
+ int cmp;
+
+ if ((cmp = strcasecmp(a->mname, b->mname)))
+ return cmp;
+
+ if ((cmp = strcasecmp(a->rname, b->rname)))
+ return cmp;
+
+ if (a->serial > b->serial)
+ return -1;
+ else if (a->serial < b->serial)
+ return 1;
+
+ if (a->refresh > b->refresh)
+ return -1;
+ else if (a->refresh < b->refresh)
+ return 1;
+
+ if (a->retry > b->retry)
+ return -1;
+ else if (a->retry < b->retry)
+ return 1;
+
+ if (a->expire > b->expire)
+ return -1;
+ else if (a->expire < b->expire)
+ return 1;
+
+ if (a->minimum > b->minimum)
+ return -1;
+ else if (a->minimum < b->minimum)
+ return 1;
+
+ return 0;
+} /* dns_soa_cmp() */
+
+
+size_t dns_soa_print(void *dst, size_t lim, struct dns_soa *soa) {
+ size_t cp = 0;
+
+ cp += dns__printstring(dst, lim, cp, soa->mname, strlen(soa->mname));
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__printstring(dst, lim, cp, soa->rname, strlen(soa->rname));
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, soa->serial, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, soa->refresh, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, soa->retry, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, soa->expire, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, soa->minimum, 0);
+
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+} /* dns_soa_print() */
+
+
+int dns_srv_parse(struct dns_srv *srv, struct dns_rr *rr, struct dns_packet *P) {
+ unsigned short rp;
+ unsigned i;
+ size_t n;
+ int error;
+
+ memset(srv, '\0', sizeof *srv);
+
+ rp = rr->rd.p;
+
+ if (P->size - P->end < 6)
+ return DNS_EILLEGAL;
+
+ for (i = 0; i < 2; i++, rp++) {
+ srv->priority <<= 8;
+ srv->priority |= (0xff & P->data[rp]);
+ }
+
+ for (i = 0; i < 2; i++, rp++) {
+ srv->weight <<= 8;
+ srv->weight |= (0xff & P->data[rp]);
+ }
+
+ for (i = 0; i < 2; i++, rp++) {
+ srv->port <<= 8;
+ srv->port |= (0xff & P->data[rp]);
+ }
+
+ if (!(n = dns_d_expand(srv->target, sizeof srv->target, rp, P, &error)))
+ return error;
+ else if (n >= sizeof srv->target)
+ return DNS_EILLEGAL;
+
+ return 0;
+} /* dns_srv_parse() */
+
+
+int dns_srv_push(struct dns_packet *P, struct dns_srv *srv) {
+ size_t end, len;
+ int error;
+
+ end = P->end;
+
+ if (P->size - P->end < 2)
+ goto toolong;
+
+ P->end += 2;
+
+ if (P->size - P->end < 6)
+ goto toolong;
+
+ P->data[P->end++] = 0xff & (srv->priority >> 8);
+ P->data[P->end++] = 0xff & (srv->priority >> 0);
+
+ P->data[P->end++] = 0xff & (srv->weight >> 8);
+ P->data[P->end++] = 0xff & (srv->weight >> 0);
+
+ P->data[P->end++] = 0xff & (srv->port >> 8);
+ P->data[P->end++] = 0xff & (srv->port >> 0);
+
+ if (0 == (len = dns_d_comp(&P->data[P->end], P->size - P->end, srv->target, strlen(srv->target), P, &error)))
+ goto error;
+ else if (P->size - P->end < len)
+ goto toolong;
+
+ P->end += len;
+
+ if (P->end > 65535)
+ goto toolong;
+
+ len = P->end - end - 2;
+
+ P->data[end + 0] = 0xff & (len >> 8);
+ P->data[end + 1] = 0xff & (len >> 0);
+
+ return 0;
+toolong:
+ error = DNS_ENOBUFS;
+
+ /* FALL THROUGH */
+error:
+ P->end = end;
+
+ return error;
+} /* dns_srv_push() */
+
+
+int dns_srv_cmp(const struct dns_srv *a, const struct dns_srv *b) {
+ int cmp;
+
+ if ((cmp = a->priority - b->priority))
+ return cmp;
+
+ /*
+ * FIXME: We need some sort of random seed to implement the dynamic
+ * weighting required by RFC 2782.
+ */
+ if ((cmp = a->weight - b->weight))
+ return cmp;
+
+ if ((cmp = a->port - b->port))
+ return cmp;
+
+ return strcasecmp(a->target, b->target);
+} /* dns_srv_cmp() */
+
+
+size_t dns_srv_print(void *dst, size_t lim, struct dns_srv *srv) {
+ size_t cp = 0;
+
+ cp += dns__print10(dst, lim, cp, srv->priority, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, srv->weight, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__print10(dst, lim, cp, srv->port, 0);
+ cp += dns__printchar(dst, lim, cp, ' ');
+ cp += dns__printstring(dst, lim, cp, srv->target, strlen(srv->target));
+
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+} /* dns_srv_print() */
+
+
+size_t dns_srv_cname(void *dst, size_t lim, struct dns_srv *srv) {
+ return dns_strlcpy(dst, srv->target, lim);
+} /* dns_srv_cname() */
+
+
+int dns_ptr_parse(struct dns_ptr *ptr, struct dns_rr *rr, struct dns_packet *P) {
+ return dns_ns_parse((struct dns_ns *)ptr, rr, P);
+} /* dns_ptr_parse() */
+
+
+int dns_ptr_push(struct dns_packet *P, struct dns_ptr *ptr) {
+ return dns_ns_push(P, (struct dns_ns *)ptr);
+} /* dns_ptr_push() */
+
+
+size_t dns_ptr_qname(void *dst, size_t lim, int af, void *addr) {
+ unsigned len = (af == AF_INET6)
+ ? dns_aaaa_arpa(dst, lim, addr)
+ : dns_a_arpa(dst, lim, addr);
+
+ dns__printnul(dst, lim, len);
+
+ return len;
+} /* dns_ptr_qname() */
+
+
+int dns_ptr_cmp(const struct dns_ptr *a, const struct dns_ptr *b) {
+ return strcasecmp(a->host, b->host);
+} /* dns_ptr_cmp() */
+
+
+size_t dns_ptr_print(void *dst, size_t lim, struct dns_ptr *ptr) {
+ return dns_ns_print(dst, lim, (struct dns_ns *)ptr);
+} /* dns_ptr_print() */
+
+
+size_t dns_ptr_cname(void *dst, size_t lim, struct dns_ptr *ptr) {
+ return dns_strlcpy(dst, ptr->host, lim);
+} /* dns_ptr_cname() */
+
+
+int dns_sshfp_parse(struct dns_sshfp *fp, struct dns_rr *rr, struct dns_packet *P) {
+ unsigned p = rr->rd.p, pe = rr->rd.p + rr->rd.len;
+
+ if (pe - p < 2)
+ return DNS_EILLEGAL;
+
+ fp->algo = P->data[p++];
+ fp->type = P->data[p++];
+
+ switch (fp->type) {
+ case DNS_SSHFP_SHA1:
+ if (pe - p < sizeof fp->digest.sha1)
+ return DNS_EILLEGAL;
+
+ memcpy(fp->digest.sha1, &P->data[p], sizeof fp->digest.sha1);
+
+ break;
+ default:
+ break;
+ } /* switch() */
+
+ return 0;
+} /* dns_sshfp_parse() */
+
+
+int dns_sshfp_push(struct dns_packet *P, struct dns_sshfp *fp) {
+ unsigned p = P->end, pe = P->size, n;
+
+ if (pe - p < 4)
+ return DNS_ENOBUFS;
+
+ p += 2;
+ P->data[p++] = 0xff & fp->algo;
+ P->data[p++] = 0xff & fp->type;
+
+ switch (fp->type) {
+ case DNS_SSHFP_SHA1:
+ if (pe - p < sizeof fp->digest.sha1)
+ return DNS_ENOBUFS;
+
+ memcpy(&P->data[p], fp->digest.sha1, sizeof fp->digest.sha1);
+ p += sizeof fp->digest.sha1;
+
+ break;
+ default:
+ return DNS_EILLEGAL;
+ } /* switch() */
+
+ n = p - P->end - 2;
+ P->data[P->end++] = 0xff & (n >> 8);
+ P->data[P->end++] = 0xff & (n >> 0);
+ P->end = p;
+
+ return 0;
+} /* dns_sshfp_push() */
+
+
+int dns_sshfp_cmp(const struct dns_sshfp *a, const struct dns_sshfp *b) {
+ int cmp;
+
+ if ((cmp = a->algo - b->algo) || (cmp - a->type - b->type))
+ return cmp;
+
+ switch (a->type) {
+ case DNS_SSHFP_SHA1:
+ return memcmp(a->digest.sha1, b->digest.sha1, sizeof a->digest.sha1);
+ default:
+ return 0;
+ } /* switch() */
+
+ /* NOT REACHED */
+} /* dns_sshfp_cmp() */
+
+
+size_t dns_sshfp_print(void *dst, size_t lim, struct dns_sshfp *fp) {
+ static const unsigned char hex[16] = "0123456789abcdef";
+ size_t i, p = 0;
+
+ p += dns__print10(dst, lim, p, fp->algo, 0);
+ p += dns__printchar(dst, lim, p, ' ');
+ p += dns__print10(dst, lim, p, fp->type, 0);
+ p += dns__printchar(dst, lim, p, ' ');
+
+ switch (fp->type) {
+ case DNS_SSHFP_SHA1:
+ for (i = 0; i < sizeof fp->digest.sha1; i++) {
+ p += dns__printchar(dst, lim, p, hex[0x0f & (fp->digest.sha1[i] >> 4)]);
+ p += dns__printchar(dst, lim, p, hex[0x0f & (fp->digest.sha1[i] >> 0)]);
+ }
+
+ break;
+ default:
+ p += dns__printchar(dst, lim, p, '0');
+
+ break;
+ } /* switch() */
+
+ dns__printnul(dst, lim, p);
+
+ return p;
+} /* dns_sshfp_print() */
+
+
+struct dns_txt *dns_txt_init(struct dns_txt *txt, size_t size) {
+ assert(size > offsetof(struct dns_txt, data));
+
+ txt->size = size - offsetof(struct dns_txt, data);
+ txt->len = 0;
+
+ return txt;
+} /* dns_txt_init() */
+
+
+int dns_txt_parse(struct dns_txt *txt, struct dns_rr *rr, struct dns_packet *P) {
+ struct { unsigned char *b; size_t p, end; } dst, src;
+ unsigned n;
+
+ dst.b = txt->data;
+ dst.p = 0;
+ dst.end = txt->size;
+
+ src.b = P->data;
+ src.p = rr->rd.p;
+ src.end = src.p + rr->rd.len;
+
+ while (src.p < src.end) {
+ n = 0xff & P->data[src.p++];
+
+ if (src.end - src.p < n || dst.end - dst.p < n)
+ return DNS_EILLEGAL;
+
+ memcpy(&dst.b[dst.p], &src.b[src.p], n);
+
+ dst.p += n;
+ src.p += n;
+ }
+
+ txt->len = dst.p;
+
+ return 0;
+} /* dns_txt_parse() */
+
+
+int dns_txt_push(struct dns_packet *P, struct dns_txt *txt) {
+ struct { unsigned char *b; size_t p, end; } dst, src;
+ unsigned n;
+
+ dst.b = P->data;
+ dst.p = P->end;
+ dst.end = P->size;
+
+ src.b = txt->data;
+ src.p = 0;
+ src.end = txt->len;
+
+ if (dst.end - dst.p < 2)
+ return DNS_ENOBUFS;
+
+ n = txt->len + ((txt->len + 254) / 255);
+
+ dst.b[dst.p++] = 0xff & (n >> 8);
+ dst.b[dst.p++] = 0xff & (n >> 0);
+
+ while (src.p < src.end) {
+ n = MIN(255, src.end - src.p);
+
+ if (dst.p >= dst.end)
+ return DNS_ENOBUFS;
+
+ dst.b[dst.p++] = n;
+
+ if (dst.end - dst.p < n)
+ return DNS_ENOBUFS;
+
+ memcpy(&dst.b[dst.p], &src.b[src.p], n);
+
+ dst.p += n;
+ src.p += n;
+ }
+
+ P->end = dst.p;
+
+ return 0;
+} /* dns_txt_push() */
+
+
+int dns_txt_cmp(const struct dns_txt *a __UNUSED__, const struct dns_txt *b __UNUSED__) {
+ return -1;
+} /* dns_txt_cmp() */
+
+
+size_t dns_txt_print(void *dst_, size_t lim, struct dns_txt *txt) {
+ struct { unsigned char *b; size_t p, end; } dst, src;
+ unsigned ch;
+
+ dst.b = dst_;
+ dst.end = lim;
+ dst.p = 0;
+
+ src.b = txt->data;
+ src.end = txt->len;
+ src.p = 0;
+
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '"');
+
+ while (src.p < src.end) {
+ ch = src.b[src.p];
+
+ if (0 == (src.p++ % 255) && src.p != 1) {
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '"');
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, ' ');
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '"');
+ }
+
+ if (ch < 32 || ch > 126 || ch == '"' || ch == '\\') {
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '\\');
+ dst.p += dns__print10(dst.b, dst.end, dst.p, ch, 3);
+ } else {
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, ch);
+ }
+ }
+
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '"');
+
+ dns__printnul(dst.b, dst.end, dst.p);
+
+ return dst.p;
+} /* dns_txt_print() */
+
+
+static const struct {
+ enum dns_type type;
+ const char *name;
+ int (*parse)();
+ int (*push)();
+ int (*cmp)();
+ size_t (*print)();
+ size_t (*cname)();
+} dns_rrtypes[] = {
+ { DNS_T_A, "A", &dns_a_parse, &dns_a_push, &dns_a_cmp, &dns_a_print, 0 },
+ { DNS_T_AAAA, "AAAA", &dns_aaaa_parse, &dns_aaaa_push, &dns_aaaa_cmp, &dns_aaaa_print, 0 },
+ { DNS_T_MX, "MX", &dns_mx_parse, &dns_mx_push, &dns_mx_cmp, &dns_mx_print, &dns_mx_cname },
+ { DNS_T_NS, "NS", &dns_ns_parse, &dns_ns_push, &dns_ns_cmp, &dns_ns_print, &dns_ns_cname },
+ { DNS_T_CNAME, "CNAME", &dns_cname_parse, &dns_cname_push, &dns_cname_cmp, &dns_cname_print, &dns_cname_cname },
+ { DNS_T_SOA, "SOA", &dns_soa_parse, &dns_soa_push, &dns_soa_cmp, &dns_soa_print, 0 },
+ { DNS_T_SRV, "SRV", &dns_srv_parse, &dns_srv_push, &dns_srv_cmp, &dns_srv_print, &dns_srv_cname },
+ { DNS_T_PTR, "PTR", &dns_ptr_parse, &dns_ptr_push, &dns_ptr_cmp, &dns_ptr_print, &dns_ptr_cname },
+ { DNS_T_TXT, "TXT", &dns_txt_parse, &dns_txt_push, &dns_txt_cmp, &dns_txt_print, 0 },
+ { DNS_T_SPF, "SPF", &dns_txt_parse, &dns_txt_push, &dns_txt_cmp, &dns_txt_print, 0 },
+ { DNS_T_SSHFP, "SSHFP", &dns_sshfp_parse, &dns_sshfp_push, &dns_sshfp_cmp, &dns_sshfp_print, 0 },
+}; /* dns_rrtypes[] */
+
+
+union dns_any *dns_any_init(union dns_any *any, size_t size) {
+ return (union dns_any *)dns_txt_init(&any->rdata, size);
+} /* dns_any_init() */
+
+
+int dns_any_parse(union dns_any *any, struct dns_rr *rr, struct dns_packet *P) {
+ unsigned i;
+
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (dns_rrtypes[i].type == rr->type)
+ return dns_rrtypes[i].parse(any, rr, P);
+ }
+
+ if (rr->rd.len > any->rdata.size)
+ return DNS_EILLEGAL;
+
+ memcpy(any->rdata.data, &P->data[rr->rd.p], rr->rd.len);
+ any->rdata.len = rr->rd.len;
+
+ return 0;
+} /* dns_any_parse() */
+
+
+int dns_any_push(struct dns_packet *P, union dns_any *any, enum dns_type type) {
+ unsigned i;
+
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (dns_rrtypes[i].type == type)
+ return dns_rrtypes[i].push(P, any);
+ }
+
+ if (P->size - P->end < any->rdata.len + 2)
+ return DNS_ENOBUFS;
+
+ P->data[P->end++] = 0xff & (any->rdata.len >> 8);
+ P->data[P->end++] = 0xff & (any->rdata.len >> 0);
+
+ memcpy(&P->data[P->end], any->rdata.data, any->rdata.len);
+ P->end += any->rdata.len;
+
+ return 0;
+} /* dns_any_push() */
+
+
+int dns_any_cmp(const union dns_any *a, enum dns_type x, const union dns_any *b, enum dns_type y) {
+ unsigned i;
+ int cmp;
+
+ if ((cmp = x - y))
+ return cmp;
+
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (dns_rrtypes[i].type == x)
+ return dns_rrtypes[i].cmp(a, b);
+ }
+
+ return -1;
+} /* dns_any_cmp() */
+
+
+size_t dns_any_print(void *dst_, size_t lim, union dns_any *any, enum dns_type type) {
+ struct { unsigned char *b; size_t p, end; } dst, src;
+ unsigned i, ch;
+
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (dns_rrtypes[i].type == type)
+ return dns_rrtypes[i].print(dst_, lim, any);
+ }
+
+ dst.b = dst_;
+ dst.end = lim;
+ dst.p = 0;
+
+ src.b = any->rdata.data;
+ src.end = any->rdata.len;
+ src.p = 0;
+
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '"');
+
+ while (src.p < src.end) {
+ ch = src.b[src.p++];
+
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '\\');
+ dst.p += dns__print10(dst.b, dst.end, dst.p, ch, 3);
+ }
+
+ dst.p += dns__printchar(dst.b, dst.end, dst.p, '"');
+
+ dns__printnul(dst.b, dst.end, dst.p);
+
+ return dst.p;
+} /* dns_any_print() */
+
+
+size_t dns_any_cname(void *dst, size_t lim, union dns_any *any, enum dns_type type) {
+ unsigned i;
+
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (dns_rrtypes[i].type == type)
+ return (dns_rrtypes[i].cname)? dns_rrtypes[i].cname(dst, lim, any) : 0;
+ }
+
+ return 0;
+} /* dns_any_cname() */
+
+
+/*
+ * H O S T S R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+struct dns_hosts {
+ struct dns_hosts_entry {
+ char host[DNS_D_MAXNAME + 1];
+ char arpa[73 + 1];
+
+ int af;
+
+ union {
+ struct in_addr a4;
+ struct in6_addr a6;
+ } addr;
+
+ _Bool alias;
+
+ struct dns_hosts_entry *next;
+ } *head, **tail;
+
+ dns_atomic_t refcount;
+}; /* struct dns_hosts */
+
+
+struct dns_hosts *dns_hosts_open(int *error) {
+ static const struct dns_hosts hosts_initializer = { .refcount = 1 };
+ struct dns_hosts *hosts;
+
+ if (!(hosts = malloc(sizeof *hosts)))
+ goto syerr;
+
+ *hosts = hosts_initializer;
+
+ hosts->tail = &hosts->head;
+
+ return hosts;
+syerr:
+ *error = dns_syerr();
+
+ free(hosts);
+
+ return 0;
+} /* dns_hosts_open() */
+
+
+void dns_hosts_close(struct dns_hosts *hosts) {
+ struct dns_hosts_entry *ent, *xnt;
+
+ if (!hosts || 1 != dns_hosts_release(hosts))
+ return;
+
+ for (ent = hosts->head; ent; ent = xnt) {
+ xnt = ent->next;
+
+ free(ent);
+ }
+
+ free(hosts);
+
+ return;
+} /* dns_hosts_close() */
+
+
+unsigned dns_hosts_acquire(struct dns_hosts *hosts) {
+ return dns_atomic_inc(&hosts->refcount);
+} /* dns_hosts_acquire() */
+
+
+unsigned dns_hosts_release(struct dns_hosts *hosts) {
+ return dns_atomic_dec(&hosts->refcount);
+} /* dns_hosts_release() */
+
+
+struct dns_hosts *dns_hosts_mortal(struct dns_hosts *hosts) {
+ if (hosts)
+ dns_hosts_release(hosts);
+
+ return hosts;
+} /* dns_hosts_mortal() */
+
+
+struct dns_hosts *dns_hosts_local(int *error_) {
+ struct dns_hosts *hosts;
+ int error;
+
+ if (!(hosts = dns_hosts_open(&error)))
+ goto error;
+
+ if ((error = dns_hosts_loadpath(hosts, "/etc/hosts")))
+ goto error;
+
+ return hosts;
+error:
+ *error_ = error;
+
+ dns_hosts_close(hosts);
+
+ return 0;
+} /* dns_hosts_local() */
+
+
+#define dns_hosts_issep(ch) (isspace(ch))
+#define dns_hosts_iscom(ch) ((ch) == '#' || (ch) == ';')
+
+int dns_hosts_loadfile(struct dns_hosts *hosts, FILE *fp) {
+ struct dns_hosts_entry ent;
+ char word[MAX(INET6_ADDRSTRLEN, DNS_D_MAXNAME) + 1];
+ unsigned wp, wc, skip;
+ int ch, error;
+
+ rewind(fp);
+
+ do {
+ memset(&ent, '\0', sizeof ent);
+ wc = 0;
+ skip = 0;
+
+ do {
+ memset(word, '\0', sizeof word);
+ wp = 0;
+
+ while (EOF != (ch = fgetc(fp)) && ch != '\n') {
+ skip |= !!dns_hosts_iscom(ch);
+
+ if (skip)
+ continue;
+
+ if (dns_hosts_issep(ch))
+ break;
+
+ if (wp < sizeof word - 1)
+ word[wp] = ch;
+ wp++;
+ }
+
+ if (!wp)
+ continue;
+
+ wc++;
+
+ switch (wc) {
+ case 0:
+ break;
+ case 1:
+ ent.af = (strchr(word, ':'))? AF_INET6 : AF_INET;
+ skip = (1 != dns_inet_pton(ent.af, word, &ent.addr));
+
+ break;
+ default:
+ if (!wp)
+ break;
+
+ dns_d_anchor(ent.host, sizeof ent.host, word, wp);
+
+ if ((error = dns_hosts_insert(hosts, ent.af, &ent.addr, ent.host, (wc > 2))))
+ return error;
+
+ break;
+ } /* switch() */
+ } while (ch != EOF && ch != '\n');
+ } while (ch != EOF);
+
+ return 0;
+} /* dns_hosts_loadfile() */
+
+
+int dns_hosts_loadpath(struct dns_hosts *hosts, const char *path) {
+ FILE *fp;
+ int error;
+
+ if (!(fp = fopen(path, "r")))
+ return dns_syerr();
+
+ error = dns_hosts_loadfile(hosts, fp);
+
+ fclose(fp);
+
+ return error;
+} /* dns_hosts_loadpath() */
+
+
+int dns_hosts_dump(struct dns_hosts *hosts, FILE *fp) {
+ struct dns_hosts_entry *ent, *xnt;
+ char addr[INET6_ADDRSTRLEN + 1];
+ unsigned i;
+
+ for (ent = hosts->head; ent; ent = xnt) {
+ xnt = ent->next;
+
+ dns_inet_ntop(ent->af, &ent->addr, addr, sizeof addr);
+
+ fputs(addr, fp);
+
+ for (i = strlen(addr); i < INET_ADDRSTRLEN; i++)
+ fputc(' ', fp);
+
+ fputc(' ', fp);
+
+ fputs(ent->host, fp);
+ fputc('\n', fp);
+ }
+
+ return 0;
+} /* dns_hosts_dump() */
+
+
+int dns_hosts_insert(struct dns_hosts *hosts, int af, const void *addr, const void *host, _Bool alias) {
+ struct dns_hosts_entry *ent;
+ int error;
+
+ if (!(ent = malloc(sizeof *ent)))
+ goto syerr;
+
+ dns_d_anchor(ent->host, sizeof ent->host, host, strlen(host));
+
+ switch ((ent->af = af)) {
+ case AF_INET6:
+ memcpy(&ent->addr.a6, addr, sizeof ent->addr.a6);
+
+ dns_aaaa_arpa(ent->arpa, sizeof ent->arpa, addr);
+
+ break;
+ case AF_INET:
+ memcpy(&ent->addr.a4, addr, sizeof ent->addr.a4);
+
+ dns_a_arpa(ent->arpa, sizeof ent->arpa, addr);
+
+ break;
+ default:
+ error = EINVAL;
+
+ goto error;
+ } /* switch() */
+
+ ent->alias = alias;
+
+ ent->next = 0;
+ *hosts->tail = ent;
+ hosts->tail = &ent->next;
+
+ return 0;
+syerr:
+ error = dns_syerr();
+error:
+ free(ent);
+
+ return error;
+} /* dns_hosts_insert() */
+
+
+struct dns_packet *dns_hosts_query(struct dns_hosts *hosts, struct dns_packet *Q, int *error_) {
+ struct dns_packet *P = dns_p_new(512);
+ struct dns_packet *A = 0;
+ struct dns_rr rr;
+ struct dns_hosts_entry *ent;
+ int error, af;
+ char qname[DNS_D_MAXNAME + 1];
+ size_t qlen;
+
+ if ((error = dns_rr_parse(&rr, 12, Q)))
+ goto error;
+
+ if (!(qlen = dns_d_expand(qname, sizeof qname, rr.dn.p, Q, &error)))
+ goto error;
+ else if (qlen >= sizeof qname)
+ goto toolong;
+
+ if ((error = dns_p_push(P, DNS_S_QD, qname, qlen, rr.type, rr.class, 0, 0)))
+ goto error;
+
+ switch (rr.type) {
+ case DNS_T_PTR:
+ for (ent = hosts->head; ent; ent = ent->next) {
+ if (ent->alias || 0 != strcasecmp(qname, ent->arpa))
+ continue;
+
+ if ((error = dns_p_push(P, DNS_S_AN, qname, qlen, rr.type, rr.class, 0, ent->host)))
+ goto error;
+ }
+
+ break;
+ case DNS_T_AAAA:
+ af = AF_INET6;
+
+ goto loop;
+ case DNS_T_A:
+ af = AF_INET;
+
+loop: for (ent = hosts->head; ent; ent = ent->next) {
+ if (ent->af != af || 0 != strcasecmp(qname, ent->host))
+ continue;
+
+ if ((error = dns_p_push(P, DNS_S_AN, qname, qlen, rr.type, rr.class, 0, &ent->addr)))
+ goto error;
+ }
+
+ break;
+ default:
+ break;
+ } /* switch() */
+
+
+ if (!(A = dns_p_copy(dns_p_make(P->end, &error), P)))
+ goto error;
+
+ return A;
+toolong:
+ error = DNS_EILLEGAL;
+error:
+ *error_ = error;
+
+ free(A);
+
+ return 0;
+} /* dns_hosts_query() */
+
+
+/*
+ * R E S O L V . C O N F R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+struct dns_resolv_conf *dns_resconf_open(int *error) {
+ static const struct dns_resolv_conf resconf_initializer
+ = { .lookup = "bf", .options = { .ndots = 1, .timeout = 5, .attempts = 2, .tcp = DNS_RESCONF_TCP_ENABLE, },
+ .iface = { .ss_family = AF_INET }, };
+ struct dns_resolv_conf *resconf;
+ struct sockaddr_in *sin;
+
+ if (!(resconf = malloc(sizeof *resconf)))
+ goto syerr;
+
+ *resconf = resconf_initializer;
+
+ sin = (struct sockaddr_in *)&resconf->nameserver[0];
+ sin->sin_family = AF_INET;
+ sin->sin_addr.s_addr = INADDR_ANY;
+ sin->sin_port = htons(53);
+#if defined(SA_LEN)
+ sin->sin_len = sizeof *sin;
+#endif
+
+ if (0 != gethostname(resconf->search[0], sizeof resconf->search[0]))
+ goto syerr;
+
+ dns_d_anchor(resconf->search[0], sizeof resconf->search[0], resconf->search[0], strlen(resconf->search[0]));
+ dns_d_cleave(resconf->search[0], sizeof resconf->search[0], resconf->search[0], strlen(resconf->search[0]));
+
+ /*
+ * XXX: If gethostname() returned a string without any label
+ * separator, then search[0][0] should be NUL.
+ */
+
+ dns_resconf_acquire(resconf);
+
+ return resconf;
+syerr:
+ *error = dns_syerr();
+
+ free(resconf);
+
+ return 0;
+} /* dns_resconf_open() */
+
+
+void dns_resconf_close(struct dns_resolv_conf *resconf) {
+ if (!resconf || 1 != dns_resconf_release(resconf))
+ return /* void */;
+
+ free(resconf);
+} /* dns_resconf_close() */
+
+
+unsigned dns_resconf_acquire(struct dns_resolv_conf *resconf) {
+ return dns_atomic_inc(&resconf->_.refcount);
+} /* dns_resconf_acquire() */
+
+
+unsigned dns_resconf_release(struct dns_resolv_conf *resconf) {
+ return dns_atomic_dec(&resconf->_.refcount);
+} /* dns_resconf_release() */
+
+
+struct dns_resolv_conf *dns_resconf_mortal(struct dns_resolv_conf *resconf) {
+ if (resconf)
+ dns_resconf_release(resconf);
+
+ return resconf;
+} /* dns_resconf_mortal() */
+
+
+struct dns_resolv_conf *dns_resconf_local(int *error_) {
+ struct dns_resolv_conf *resconf;
+ int error;
+
+ if (!(resconf = dns_resconf_open(&error)))
+ goto error;
+
+ if ((error = dns_resconf_loadpath(resconf, "/etc/resolv.conf")))
+ goto error;
+
+ return resconf;
+error:
+ *error_ = error;
+
+ dns_resconf_close(resconf);
+
+ return 0;
+} /* dns_resconf_local() */
+
+
+struct dns_resolv_conf *dns_resconf_root(int *error_) {
+ struct dns_resolv_conf *resconf;
+ int error;
+
+ if (!(resconf = dns_resconf_open(&error)))
+ goto error;
+
+ if ((error = dns_resconf_loadpath(resconf, "/etc/resolv.conf")))
+ goto error;
+
+ resconf->options.recurse = 1;
+
+ return resconf;
+error:
+ *error_ = error;
+
+ dns_resconf_close(resconf);
+
+ return 0;
+} /* dns_resconf_root() */
+
+
+enum dns_resconf_keyword {
+ DNS_RESCONF_NAMESERVER,
+ DNS_RESCONF_DOMAIN,
+ DNS_RESCONF_SEARCH,
+ DNS_RESCONF_LOOKUP,
+ DNS_RESCONF_FILE,
+ DNS_RESCONF_BIND,
+ DNS_RESCONF_CACHE,
+ DNS_RESCONF_OPTIONS,
+ DNS_RESCONF_EDNS0,
+ DNS_RESCONF_NDOTS,
+ DNS_RESCONF_TIMEOUT,
+ DNS_RESCONF_ATTEMPTS,
+ DNS_RESCONF_ROTATE,
+ DNS_RESCONF_RECURSE,
+ DNS_RESCONF_SMART,
+ DNS_RESCONF_TCP,
+ DNS_RESCONF_TCPx,
+ DNS_RESCONF_INTERFACE,
+ DNS_RESCONF_ZERO,
+ DNS_RESCONF_ONE,
+ DNS_RESCONF_ENABLE,
+ DNS_RESCONF_ONLY,
+ DNS_RESCONF_DISABLE,
+}; /* enum dns_resconf_keyword */
+
+static enum dns_resconf_keyword dns_resconf_keyword(const char *word) {
+ static const char *words[] = {
+ [DNS_RESCONF_NAMESERVER] = "nameserver",
+ [DNS_RESCONF_DOMAIN] = "domain",
+ [DNS_RESCONF_SEARCH] = "search",
+ [DNS_RESCONF_LOOKUP] = "lookup",
+ [DNS_RESCONF_FILE] = "file",
+ [DNS_RESCONF_BIND] = "bind",
+ [DNS_RESCONF_CACHE] = "cache",
+ [DNS_RESCONF_OPTIONS] = "options",
+ [DNS_RESCONF_EDNS0] = "edns0",
+ [DNS_RESCONF_ROTATE] = "rotate",
+ [DNS_RESCONF_RECURSE] = "recurse",
+ [DNS_RESCONF_SMART] = "smart",
+ [DNS_RESCONF_TCP] = "tcp",
+ [DNS_RESCONF_INTERFACE] = "interface",
+ [DNS_RESCONF_ZERO] = "0",
+ [DNS_RESCONF_ONE] = "1",
+ [DNS_RESCONF_ENABLE] = "enable",
+ [DNS_RESCONF_ONLY] = "only",
+ [DNS_RESCONF_DISABLE] = "disable",
+ };
+ unsigned i;
+
+ for (i = 0; i < lengthof(words); i++) {
+ if (words[i] && 0 == strcasecmp(words[i], word))
+ return i;
+ }
+
+ if (0 == strncasecmp(word, "ndots:", sizeof "ndots:" - 1))
+ return DNS_RESCONF_NDOTS;
+
+ if (0 == strncasecmp(word, "timeout:", sizeof "timeout:" - 1))
+ return DNS_RESCONF_TIMEOUT;
+
+ if (0 == strncasecmp(word, "attempts:", sizeof "attempts:" - 1))
+ return DNS_RESCONF_ATTEMPTS;
+
+ if (0 == strncasecmp(word, "tcp:", sizeof "tcp:" - 1))
+ return DNS_RESCONF_TCPx;
+
+ return -1;
+} /* dns_resconf_keyword() */
+
+
+/** OpenBSD-style "[1.2.3.4]:53" nameserver syntax */
+static int dns_resconf_pton(struct sockaddr_storage *ss, const char *src) {
+ struct { char buf[128], *p; } addr = { "", addr.buf };
+ unsigned short port = 0;
+ int ch, af = AF_INET;
+
+ while ((ch = *src++)) {
+ switch (ch) {
+ case ' ':
+ /* FALL THROUGH */
+ case '\t':
+ break;
+ case '[':
+ break;
+ case ']':
+ while ((ch = *src++)) {
+ if (isdigit((unsigned char)ch)) {
+ port *= 10;
+ port += ch - '0';
+ }
+ }
+
+ goto inet;
+ case ':':
+ af = AF_INET6;
+
+ /* FALL THROUGH */
+ default:
+ if (addr.p < endof(addr.buf) - 1)
+ *addr.p++ = ch;
+
+ break;
+ } /* switch() */
+ } /* while() */
+inet:
+
+ switch (dns_inet_pton(af, addr.buf, dns_sa_addr(af, ss))) {
+ case -1:
+ return errno;
+ case 0:
+ return EINVAL;
+ } /* switch() */
+
+ port = (!port)? 53 : port;
+ *dns_sa_port(af, ss) = htons(port);
+ dns_sa_family(ss) = af;
+
+ return 0;
+} /* dns_resconf_pton() */
+
+#define dns_resconf_issep(ch) (isspace(ch) || (ch) == ',')
+#define dns_resconf_iscom(ch) ((ch) == '#' || (ch) == ';')
+
+int dns_resconf_loadfile(struct dns_resolv_conf *resconf, FILE *fp) {
+ unsigned sa_count = 0;
+ char words[6][DNS_D_MAXNAME + 1];
+ unsigned wp, wc, i, j, n;
+ int ch, error;
+
+ rewind(fp);
+
+ do {
+ memset(words, '\0', sizeof words);
+ wp = 0;
+ wc = 0;
+
+ while (EOF != (ch = getc(fp)) && ch != '\n') {
+ if (dns_resconf_issep(ch)) {
+ if (wp > 0) {
+ wp = 0;
+
+ if (++wc >= lengthof(words))
+ goto skip;
+ }
+ } else if (dns_resconf_iscom(ch)) {
+skip:
+ do {
+ ch = getc(fp);
+ } while (ch != EOF && ch != '\n');
+
+ break;
+ } else {
+ dns__printchar(words[wc], sizeof words[wc], wp, ch);
+ wp++;
+ }
+ }
+
+ if (wp > 0)
+ wc++;
+
+ if (wc < 2)
+ continue;
+
+ switch (dns_resconf_keyword(words[0])) {
+ case DNS_RESCONF_NAMESERVER:
+ if (sa_count >= lengthof(resconf->nameserver))
+ continue;
+
+ if ((error = dns_resconf_pton(&resconf->nameserver[sa_count], words[1])))
+ continue;
+
+ sa_count++;
+
+ break;
+ case DNS_RESCONF_DOMAIN:
+ case DNS_RESCONF_SEARCH:
+ memset(resconf->search, '\0', sizeof resconf->search);
+
+ for (i = 1, j = 0; i < wc && j < lengthof(resconf->search); i++, j++)
+ dns_d_anchor(resconf->search[j], sizeof resconf->search[j], words[i], strlen(words[i]));
+
+ break;
+ case DNS_RESCONF_LOOKUP:
+ for (i = 1, j = 0; i < wc && j < lengthof(resconf->lookup); i++) {
+ switch (dns_resconf_keyword(words[i])) {
+ case DNS_RESCONF_FILE:
+ resconf->lookup[j++] = 'f';
+
+ break;
+ case DNS_RESCONF_BIND:
+ resconf->lookup[j++] = 'b';
+
+ break;
+ case DNS_RESCONF_CACHE:
+ resconf->lookup[j++] = 'c';
+
+ break;
+ default:
+ break;
+ } /* switch() */
+ } /* for() */
+
+ break;
+ case DNS_RESCONF_OPTIONS:
+ for (i = 1; i < wc; i++) {
+ switch (dns_resconf_keyword(words[i])) {
+ case DNS_RESCONF_EDNS0:
+ resconf->options.edns0 = 1;
+
+ break;
+ case DNS_RESCONF_NDOTS:
+ for (j = sizeof "ndots:" - 1, n = 0; isdigit((int)words[i][j]); j++) {
+ n *= 10;
+ n += words[i][j] - '0';
+ } /* for() */
+
+ resconf->options.ndots = n;
+
+ break;
+ case DNS_RESCONF_TIMEOUT:
+ for (j = sizeof "timeout:" - 1, n = 0; isdigit((int)words[i][j]); j++) {
+ n *= 10;
+ n += words[i][j] - '0';
+ } /* for() */
+
+ resconf->options.timeout = n;
+
+ break;
+ case DNS_RESCONF_ATTEMPTS:
+ for (j = sizeof "attempts:" - 1, n = 0; isdigit((int)words[i][j]); j++) {
+ n *= 10;
+ n += words[i][j] - '0';
+ } /* for() */
+
+ resconf->options.attempts = n;
+
+ break;
+ case DNS_RESCONF_ROTATE:
+ resconf->options.rotate = 1;
+
+ break;
+ case DNS_RESCONF_RECURSE:
+ resconf->options.recurse = 1;
+
+ break;
+ case DNS_RESCONF_SMART:
+ resconf->options.smart = 1;
+
+ break;
+ case DNS_RESCONF_TCP:
+ resconf->options.tcp = DNS_RESCONF_TCP_ONLY;
+
+ break;
+ case DNS_RESCONF_TCPx:
+ switch (dns_resconf_keyword(&words[i][sizeof "tcp:" - 1])) {
+ case DNS_RESCONF_ENABLE:
+ resconf->options.tcp = DNS_RESCONF_TCP_ENABLE;
+
+ break;
+ case DNS_RESCONF_ONE:
+ case DNS_RESCONF_ONLY:
+ resconf->options.tcp = DNS_RESCONF_TCP_ONLY;
+
+ break;
+ case DNS_RESCONF_ZERO:
+ case DNS_RESCONF_DISABLE:
+ resconf->options.tcp = DNS_RESCONF_TCP_DISABLE;
+
+ break;
+ default:
+ break;
+ } /* switch() */
+
+ break;
+ default:
+ break;
+ } /* switch() */
+ } /* for() */
+
+ break;
+ case DNS_RESCONF_INTERFACE:
+ for (i = 0, n = 0; isdigit((int)words[2][i]); i++) {
+ n *= 10;
+ n += words[2][i] - '0';
+ }
+
+ dns_resconf_setiface(resconf, words[1], n);
+
+ break;
+ default:
+ break;
+ } /* switch() */
+ } while (ch != EOF);
+
+ return 0;
+} /* dns_resconf_loadfile() */
+
+
+int dns_resconf_loadpath(struct dns_resolv_conf *resconf, const char *path) {
+ FILE *fp;
+ int error;
+
+ if (!(fp = fopen(path, "r")))
+ return dns_syerr();
+
+ error = dns_resconf_loadfile(resconf, fp);
+
+ fclose(fp);
+
+ return error;
+} /* dns_resconf_loadpath() */
+
+
+int dns_resconf_setiface(struct dns_resolv_conf *resconf, const char *addr, unsigned short port) {
+ int af = (strchr(addr, ':'))? AF_INET6 : AF_INET;
+
+ if (1 != dns_inet_pton(af, addr, dns_sa_addr(af, &resconf->iface)))
+ return dns_soerr();
+
+ *dns_sa_port(af, &resconf->iface) = htons(port);
+ resconf->iface.ss_family = af;
+
+ return 0;
+} /* dns_resconf_setiface() */
+
+
+size_t dns_resconf_search(void *dst, size_t lim, const void *qname, size_t qlen, struct dns_resolv_conf *resconf, dns_resconf_i_t *state) {
+ unsigned srchi = 0xff & (*state >> 8);
+ unsigned ndots = 0xff & (*state >> 16);
+ unsigned slen, len = 0;
+ const char *qp, *qe;
+
+// assert(0xff > lengthof(resconf->search));
+
+ switch (0xff & *state) {
+ case 0:
+ qp = qname;
+ qe = qp + qlen;
+
+ while ((qp = memchr(qp, '.', qe - qp)))
+ { ndots++; qp++; }
+
+ ++*state;
+
+ if (ndots >= resconf->options.ndots) {
+ len = dns_d_anchor(dst, lim, qname, qlen);
+
+ break;
+ }
+
+ /* FALL THROUGH */
+ case 1:
+ if (srchi < lengthof(resconf->search) && (slen = strlen(resconf->search[srchi]))) {
+ len = dns__printstring(dst, lim, 0, qname, qlen);
+ len = dns_d_anchor(dst, lim, dst, len);
+ len += dns__printstring(dst, lim, len, resconf->search[srchi], slen);
+
+ srchi++;
+
+ break;
+ }
+
+ ++*state;
+
+ /* FALL THROUGH */
+ case 2:
+ ++*state;
+
+ if (ndots < resconf->options.ndots) {
+ len = dns_d_anchor(dst, lim, qname, qlen);
+
+ break;
+ }
+
+ /* FALL THROUGH */
+ default:
+ break;
+ } /* switch() */
+
+ dns__printnul(dst, lim, len);
+
+ *state = ((0xff & *state) << 0)
+ | ((0xff & srchi) << 8)
+ | ((0xff & ndots) << 16);
+
+ return len;
+} /* dns_resconf_search() */
+
+
+int dns_resconf_dump(struct dns_resolv_conf *resconf, FILE *fp) {
+ unsigned i;
+ int af;
+
+ for (i = 0; i < lengthof(resconf->nameserver) && (af = resconf->nameserver[i].ss_family) != AF_UNSPEC; i++) {
+ char addr[INET6_ADDRSTRLEN + 1] = "[INVALID]";
+ unsigned short port;
+
+ dns_inet_ntop(af, dns_sa_addr(af, &resconf->nameserver[i]), addr, sizeof addr);
+ port = ntohs(*dns_sa_port(af, &resconf->nameserver[i]));
+
+ if (port == 53)
+ fprintf(fp, "nameserver %s\n", addr);
+ else
+ fprintf(fp, "nameserver [%s]:%hu\n", addr, port);
+ }
+
+
+ fprintf(fp, "search");
+
+ for (i = 0; i < lengthof(resconf->search) && resconf->search[i][0]; i++)
+ fprintf(fp, " %s", resconf->search[i]);
+
+ fputc('\n', fp);
+
+
+ fprintf(fp, "lookup");
+
+ for (i = 0; i < lengthof(resconf->lookup) && resconf->lookup[i]; i++) {
+ switch (resconf->lookup[i]) {
+ case 'b':
+ fprintf(fp, " bind"); break;
+ case 'f':
+ fprintf(fp, " file"); break;
+ case 'c':
+ fprintf(fp, " cache"); break;
+ }
+ }
+
+ fputc('\n', fp);
+
+
+ fprintf(fp, "options ndots:%u timeout:%u attempts:%u", resconf->options.ndots, resconf->options.timeout, resconf->options.attempts);
+
+ if (resconf->options.edns0)
+ fprintf(fp, " edns0");
+ if (resconf->options.rotate)
+ fprintf(fp, " rotate");
+ if (resconf->options.recurse)
+ fprintf(fp, " recurse");
+ if (resconf->options.smart)
+ fprintf(fp, " smart");
+
+ fputc('\n', fp);
+
+
+ if ((af = resconf->iface.ss_family) != AF_UNSPEC) {
+ char addr[INET6_ADDRSTRLEN + 1] = "[INVALID]";
+
+ dns_inet_ntop(af, dns_sa_addr(af, &resconf->iface), addr, sizeof addr);
+
+ fprintf(fp, "interface %s %hu\n", addr, ntohs(*dns_sa_port(af, &resconf->iface)));
+ }
+
+ return 0;
+} /* dns_resconf_dump() */
+
+
+/*
+ * H I N T S E R V E R R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+struct dns_hints_soa {
+ unsigned char zone[DNS_D_MAXNAME + 1];
+
+ struct {
+ struct sockaddr_storage ss;
+ unsigned priority;
+ } addrs[16];
+
+ unsigned count;
+
+ struct dns_hints_soa *next;
+}; /* struct dns_hints_soa */
+
+
+struct dns_hints {
+ dns_atomic_t refcount;
+
+ struct dns_hints_soa *head;
+}; /* struct dns_hints */
+
+
+struct dns_hints *dns_hints_open(struct dns_resolv_conf *resconf __UNUSED__, int *error) {
+ static const struct dns_hints H_initializer;
+ struct dns_hints *H;
+
+ if (!(H = malloc(sizeof *H)))
+ goto syerr;
+
+ *H = H_initializer;
+
+ dns_hints_acquire(H);
+
+ return H;
+syerr:
+ *error = dns_syerr();
+
+ free(H);
+
+ return 0;
+} /* dns_hints_open() */
+
+
+void dns_hints_close(struct dns_hints *H) {
+ struct dns_hints_soa *soa, *nxt;
+
+ if (!H || 1 != dns_hints_release(H))
+ return /* void */;
+
+ for (soa = H->head; soa; soa = nxt) {
+ nxt = soa->next;
+
+ free(soa);
+ }
+
+ free(H);
+
+ return /* void */;
+} /* dns_hints_close() */
+
+
+unsigned dns_hints_acquire(struct dns_hints *H) {
+ return dns_atomic_inc(&H->refcount);
+} /* dns_hints_acquire() */
+
+
+unsigned dns_hints_release(struct dns_hints *H) {
+ return dns_atomic_dec(&H->refcount);
+} /* dns_hints_release() */
+
+
+struct dns_hints *dns_hints_mortal(struct dns_hints *hints) {
+ if (hints)
+ dns_hints_release(hints);
+
+ return hints;
+} /* dns_hints_mortal() */
+
+
+struct dns_hints *dns_hints_local(struct dns_resolv_conf *resconf, int *error_) {
+ struct dns_hints *hints = 0;
+ int error;
+
+ if (resconf)
+ dns_resconf_acquire(resconf);
+ else if (!(resconf = dns_resconf_local(&error)))
+ goto error;
+
+ if (!(hints = dns_hints_open(resconf, &error)))
+ goto error;
+
+ error = 0;
+
+ if (0 == dns_hints_insert_resconf(hints, ".", resconf, &error) && error)
+ goto error;
+
+ dns_resconf_close(resconf);
+
+ return hints;
+error:
+ *error_ = error;
+
+ dns_resconf_close(resconf);
+ dns_hints_close(hints);
+
+ return 0;
+} /* dns_hints_local() */
+
+
+struct dns_hints *dns_hints_root(struct dns_resolv_conf *resconf, int *error_) {
+ static const struct {
+ int af;
+ char addr[INET6_ADDRSTRLEN];
+ } root_hints[] = {
+ { AF_INET, "198.41.0.4" }, /* A.ROOT-SERVERS.NET. */
+ { AF_INET6, "2001:503:ba3e::2:30" }, /* A.ROOT-SERVERS.NET. */
+ { AF_INET, "192.228.79.201" }, /* B.ROOT-SERVERS.NET. */
+ { AF_INET, "192.33.4.12" }, /* C.ROOT-SERVERS.NET. */
+ { AF_INET, "128.8.10.90" }, /* D.ROOT-SERVERS.NET. */
+ { AF_INET, "192.203.230.10" }, /* E.ROOT-SERVERS.NET. */
+ { AF_INET, "192.5.5.241" }, /* F.ROOT-SERVERS.NET. */
+ { AF_INET6, "2001:500:2f::f" }, /* F.ROOT-SERVERS.NET. */
+ { AF_INET, "192.112.36.4" }, /* G.ROOT-SERVERS.NET. */
+ { AF_INET, "128.63.2.53" }, /* H.ROOT-SERVERS.NET. */
+ { AF_INET6, "2001:500:1::803f:235" }, /* H.ROOT-SERVERS.NET. */
+ { AF_INET, "192.36.148.17" }, /* I.ROOT-SERVERS.NET. */
+ { AF_INET, "192.58.128.30" }, /* J.ROOT-SERVERS.NET. */
+ { AF_INET6, "2001:503:c27::2:30" }, /* J.ROOT-SERVERS.NET. */
+ };
+ struct dns_hints *hints = 0;
+ struct sockaddr_storage ss;
+ unsigned i;
+ int error, af;
+
+ if (!(hints = dns_hints_open(resconf, &error)))
+ goto error;
+
+ for (i = 0; i < lengthof(root_hints); i++) {
+ af = root_hints[i].af;
+
+ if (1 != dns_inet_pton(af, root_hints[i].addr, dns_sa_addr(af, &ss)))
+ goto soerr;
+
+ *dns_sa_port(af, &ss) = htons(53);
+ ss.ss_family = af;
+
+ if ((error = dns_hints_insert(hints, ".", (struct sockaddr *)&ss, 1)))
+ goto error;
+ }
+
+ return hints;
+soerr:
+ error = dns_soerr();
+
+ goto error;
+error:
+ *error_ = error;
+
+ dns_hints_close(hints);
+
+ return 0;
+} /* dns_hints_root() */
+
+
+static struct dns_hints_soa *dns_hints_fetch(struct dns_hints *H, const char *zone) {
+ struct dns_hints_soa *soa;
+
+ for (soa = H->head; soa; soa = soa->next) {
+ if (0 == strcasecmp(zone, (char *)soa->zone))
+ return soa;
+ }
+
+ return 0;
+} /* dns_hints_fetch() */
+
+
+int dns_hints_insert(struct dns_hints *H, const char *zone, const struct sockaddr *sa, unsigned priority) {
+ static const struct dns_hints_soa soa_initializer;
+ struct dns_hints_soa *soa;
+ unsigned i;
+
+ if (!(soa = dns_hints_fetch(H, zone))) {
+ if (!(soa = malloc(sizeof *soa)))
+ return dns_syerr();
+
+ *soa = soa_initializer;
+
+ dns__printstring(soa->zone, sizeof soa->zone, 0, zone);
+
+ soa->next = H->head;
+ H->head = soa;
+ }
+
+ i = soa->count % lengthof(soa->addrs);
+
+ memcpy(&soa->addrs[i].ss, sa, dns_sa_len(sa));
+
+ soa->addrs[i].priority = MAX(1, priority);
+
+ if (soa->count < lengthof(soa->addrs))
+ soa->count++;
+
+ return 0;
+} /* dns_hints_insert() */
+
+
+unsigned dns_hints_insert_resconf(struct dns_hints *H, const char *zone, const struct dns_resolv_conf *resconf, int *error_) {
+ unsigned i, n, p;
+ int error;
+
+ for (i = 0, n = 0, p = 1; i < lengthof(resconf->nameserver) && resconf->nameserver[i].ss_family != AF_UNSPEC; i++, n++) {
+ if ((error = dns_hints_insert(H, zone, (struct sockaddr *)&resconf->nameserver[i], p)))
+ goto error;
+
+ p += !resconf->options.rotate;
+ }
+
+ return n;
+error:
+ *error_ = error;
+
+ return n;
+} /* dns_hints_insert_resconf() */
+
+
+static int dns_hints_i_cmp(unsigned a, unsigned b, struct dns_hints_i *i, struct dns_hints_soa *soa) {
+ int cmp;
+
+ if ((cmp = soa->addrs[a].priority - soa->addrs[b].priority))
+ return cmp;
+
+ return dns_k_shuffle16(a, i->state.seed) - dns_k_shuffle16(b, i->state.seed);
+} /* dns_hints_i_cmp() */
+
+
+static unsigned dns_hints_i_start(struct dns_hints_i *i, struct dns_hints_soa *soa) {
+ unsigned p0, p;
+
+ p0 = 0;
+
+ for (p = 1; p < soa->count; p++) {
+ if (dns_hints_i_cmp(p, p0, i, soa) < 0)
+ p0 = p;
+ }
+
+ return p0;
+} /* dns_hints_i_start() */
+
+
+static unsigned dns_hints_i_skip(unsigned p0, struct dns_hints_i *i, struct dns_hints_soa *soa) {
+ unsigned pZ, p;
+
+ for (pZ = 0; pZ < soa->count; pZ++) {
+ if (dns_hints_i_cmp(pZ, p0, i, soa) > 0)
+ goto cont;
+ }
+
+ return soa->count;
+cont:
+ for (p = pZ + 1; p < soa->count; p++) {
+ if (dns_hints_i_cmp(p, p0, i, soa) <= 0)
+ continue;
+
+ if (dns_hints_i_cmp(p, pZ, i, soa) >= 0)
+ continue;
+
+ pZ = p;
+ }
+
+
+ return pZ;
+} /* dns_hints_i_skip() */
+
+
+struct dns_hints_i *dns_hints_i_init(struct dns_hints_i *i, struct dns_hints *hints) {
+ static const struct dns_hints_i i_initializer;
+ struct dns_hints_soa *soa;
+
+ i->state = i_initializer.state;
+
+ do {
+ i->state.seed = dns_random();
+ } while (0 == i->state.seed);
+
+ if ((soa = dns_hints_fetch(hints, i->zone))) {
+ i->state.next = dns_hints_i_start(i, soa);
+ }
+
+ return i;
+} /* dns_hints_i_init() */
+
+
+unsigned dns_hints_grep(struct sockaddr **sa, socklen_t *sa_len, unsigned lim, struct dns_hints_i *i, struct dns_hints *H) {
+ struct dns_hints_soa *soa;
+ unsigned n;
+
+ if (!(soa = dns_hints_fetch(H, i->zone)))
+ return 0;
+
+ n = 0;
+
+ while (i->state.next < soa->count && n < lim) {
+ *sa = (struct sockaddr *)&soa->addrs[i->state.next].ss;
+ *sa_len = dns_sa_len(*sa);
+
+ sa++;
+ sa_len++;
+ n++;
+
+ i->state.next = dns_hints_i_skip(i->state.next, i, soa);
+ }
+
+ return n;
+} /* dns_hints_grep() */
+
+
+struct dns_packet *dns_hints_query(struct dns_hints *hints, struct dns_packet *Q, int *error_) {
+ struct dns_packet *A, *P;
+ struct dns_rr rr;
+ char zone[DNS_D_MAXNAME + 1];
+ size_t zlen;
+ struct dns_hints_i i;
+ struct sockaddr *sa;
+ socklen_t slen;
+ int error;
+
+ if (!dns_rr_grep(&rr, 1, dns_rr_i_new(Q, .section = DNS_S_QUESTION), Q, &error))
+ goto error;
+
+ if (!(zlen = dns_d_expand(zone, sizeof zone, rr.dn.p, Q, &error)))
+ goto error;
+ else if (zlen >= sizeof zone)
+ goto toolong;
+
+ P = dns_p_new(512);
+ dns_header(P)->qr = 1;
+
+ if ((error = dns_rr_copy(P, &rr, Q)))
+ goto error;
+
+ if ((error = dns_p_push(P, DNS_S_AUTHORITY, ".", strlen("."), DNS_T_NS, DNS_C_IN, 0, "hints.local.")))
+ goto error;
+
+ do {
+ i.zone = zone;
+
+ dns_hints_i_init(&i, hints);
+
+ while (dns_hints_grep(&sa, &slen, 1, &i, hints)) {
+ int af = sa->sa_family;
+ int rtype = (af == AF_INET6)? DNS_T_AAAA : DNS_T_A;
+
+ if ((error = dns_p_push(P, DNS_S_ADDITIONAL, "hints.local.", strlen("hints.local."), rtype, DNS_C_IN, 0, dns_sa_addr(af, sa))))
+ goto error;
+ }
+ } while ((zlen = dns_d_cleave(zone, sizeof zone, zone, zlen)));
+
+ if (!(A = dns_p_copy(dns_p_make(P->end, &error), P)))
+ goto error;
+
+ return A;
+toolong:
+ error = DNS_EILLEGAL;
+error:
+ *error_ = error;
+
+ return 0;
+} /* dns_hints_query() */
+
+
+/** ugly hack to support specifying ports other than 53 in resolv.conf. */
+static unsigned short dns_hints_port(struct dns_hints *hints, int af, void *addr) {
+ struct dns_hints_soa *soa;
+ unsigned short port;
+ unsigned i;
+
+ for (soa = hints->head; soa; soa = soa->next) {
+ for (i = 0; i < soa->count; i++) {
+ if (af != soa->addrs[i].ss.ss_family)
+ continue;
+
+ if (memcmp(addr, dns_sa_addr(af, &soa->addrs[i].ss), (af == AF_INET6)? sizeof (struct in6_addr) : sizeof (struct in_addr)))
+ continue;
+
+ port = *dns_sa_port(af, &soa->addrs[i].ss);
+
+ return (port)? port : htons(53);
+ }
+ }
+
+ return htons(53);
+} /* dns_hints_port() */
+
+
+int dns_hints_dump(struct dns_hints *hints, FILE *fp) {
+ struct dns_hints_soa *soa;
+ char addr[INET6_ADDRSTRLEN];
+ unsigned i;
+ int af;
+
+ for (soa = hints->head; soa; soa = soa->next) {
+ fprintf(fp, "ZONE \"%s\"\n", soa->zone);
+
+ for (i = 0; i < soa->count; i++) {
+ af = soa->addrs[i].ss.ss_family;
+ if (!dns_inet_ntop(af, dns_sa_addr(af, &soa->addrs[i].ss), addr, sizeof addr))
+ return dns_soerr();
+
+ fprintf(fp, "\t(%d) [%s]:%hu\n", (int)soa->addrs[i].priority, addr, ntohs(*dns_sa_port(af, &soa->addrs[i].ss)));
+ }
+ }
+
+ return 0;
+} /* dns_hints_dump() */
+
+
+/*
+ * C A C H E R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+static dns_atomic_t dns_cache_acquire(struct dns_cache *cache __UNUSED__) {
+ return 0;
+} /* dns_cache_acquire() */
+
+
+static dns_atomic_t dns_cache_release(struct dns_cache *cache __UNUSED__) {
+ return 0;
+} /* dns_cache_release() */
+
+
+static struct dns_packet *dns_cache_query(struct dns_packet *query __UNUSED__, struct dns_cache *cache __UNUSED__, int *error __UNUSED__) {
+ return 0;
+} /* dns_cache_submit() */
+
+
+static int dns_cache_submit(struct dns_packet *query __UNUSED__, struct dns_cache *cache __UNUSED__) {
+ return 0;
+} /* dns_cache_submit() */
+
+
+static int dns_cache_check(struct dns_cache *cache __UNUSED__) {
+ return 0;
+} /* dns_cache_check() */
+
+
+static struct dns_packet *dns_cache_fetch(struct dns_cache *cache __UNUSED__, int *error __UNUSED__) {
+ return 0;
+} /* dns_cache_fetch() */
+
+
+static int dns_cache_pollfd(struct dns_cache *cache __UNUSED__) {
+ return -1;
+} /* dns_cache_pollfd() */
+
+
+static short dns_cache_events(struct dns_cache *cache __UNUSED__) {
+ return 0;
+} /* dns_cache_events() */
+
+
+static void dns_cache_clear(struct dns_cache *cache __UNUSED__) {
+ return;
+} /* dns_cache_clear() */
+
+
+struct dns_cache *dns_cache_init(struct dns_cache *cache) {
+ static const struct dns_cache c_init = {
+ .acquire = &dns_cache_acquire,
+ .release = &dns_cache_release,
+ .query = &dns_cache_query,
+ .submit = &dns_cache_submit,
+ .check = &dns_cache_check,
+ .fetch = &dns_cache_fetch,
+ .pollfd = &dns_cache_pollfd,
+ .events = &dns_cache_events,
+ .clear = &dns_cache_clear,
+ };
+
+ *cache = c_init;
+
+ return cache;
+} /* dns_cache_init() */
+
+
+void dns_cache_close(struct dns_cache *cache) {
+ if (cache)
+ cache->release(cache);
+} /* dns_cache_close() */
+
+
+/*
+ * S O C K E T R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+static void dns_socketclose(int *fd) {
+ if (*fd != -1) {
+#if _WIN32
+ closesocket(*fd);
+#else
+ close(*fd);
+#endif
+ *fd = -1;
+ }
+} /* dns_socketclose() */
+
+
+#define DNS_SO_MAXTRY 7
+
+static int dns_socket(struct sockaddr *local, int type, int *error_) {
+ int error, fd = -1;
+#if defined(O_NONBLOCK)
+ int flags;
+#elif defined(FIONBIO)
+ unsigned long opt;
+#endif
+
+ if (-1 == (fd = socket(local->sa_family, type, 0)))
+ goto soerr;
+
+#if defined(F_SETFD)
+ if (-1 == fcntl(fd, F_SETFD, 1))
+ goto syerr;
+#endif
+
+#if defined(O_NONBLOCK)
+ if (-1 == (flags = fcntl(fd, F_GETFL)))
+ goto syerr;
+
+ if (-1 == fcntl(fd, F_SETFL, flags | O_NONBLOCK))
+ goto syerr;
+#elif defined(FIONBIO)
+ opt = 1;
+
+ if (0 != ioctlsocket(fd, FIONBIO, &opt))
+ goto soerr;
+#endif
+
+ if (local->sa_family != AF_INET && local->sa_family != AF_INET6)
+ return fd;
+
+ if (type != SOCK_DGRAM)
+ return fd;
+
+ if (*dns_sa_port(local->sa_family, local) == 0) {
+ struct sockaddr_storage tmp;
+ unsigned i, port;
+
+ memcpy(&tmp, local, dns_sa_len(local));
+
+ for (i = 0; i < DNS_SO_MAXTRY; i++) {
+ port = 1025 + (dns_random() % 64510);
+
+ *dns_sa_port(tmp.ss_family, &tmp) = htons(port);
+
+ if (0 == bind(fd, (struct sockaddr *)&tmp, dns_sa_len(&tmp)))
+ return fd;
+ }
+ }
+
+ if (0 == bind(fd, local, dns_sa_len(local)))
+ return fd;
+
+ /* FALL THROUGH */
+soerr:
+ error = dns_soerr();
+
+ goto error;
+syerr:
+ error = dns_syerr();
+
+ goto error;
+error:
+ *error_ = error;
+
+ dns_socketclose(&fd);
+
+ return -1;
+} /* dns_socket() */
+
+
+enum {
+ DNS_SO_UDP_INIT = 1,
+ DNS_SO_UDP_CONN,
+ DNS_SO_UDP_SEND,
+ DNS_SO_UDP_RECV,
+ DNS_SO_UDP_DONE,
+
+ DNS_SO_TCP_INIT,
+ DNS_SO_TCP_CONN,
+ DNS_SO_TCP_SEND,
+ DNS_SO_TCP_RECV,
+ DNS_SO_TCP_DONE,
+};
+
+struct dns_socket {
+ struct dns_options opts;
+
+ int udp;
+ int tcp;
+
+ int *old;
+ unsigned onum, olim;
+
+ int type;
+
+ struct sockaddr_storage local, remote;
+
+ struct dns_k_permutor qids;
+
+ struct dns_stat stat;
+
+ /*
+ * NOTE: dns_so_reset() zeroes everything from here down.
+ */
+ int state;
+
+ unsigned short qid;
+ char qname[DNS_D_MAXNAME + 1];
+ size_t qlen;
+ enum dns_type qtype;
+ enum dns_class qclass;
+
+ struct dns_packet *query;
+ size_t qout;
+
+ time_t began;
+
+ struct dns_packet *answer;
+ size_t alen, apos;
+}; /* struct dns_socket() */
+
+
+/*
+ * NOTE: Actual closure delayed so that kqueue(2) and epoll(2) callers have
+ * a chance to recognize a state change after installing a persistent event
+ * and where sequential descriptors with the same integer value returned
+ * from _pollfd() would be ambiguous. See dns_so_closefds().
+ */
+static int dns_so_closefd(struct dns_socket *so, int *fd) {
+ int error;
+
+ if (*fd == -1)
+ return 0;
+
+ if (so->opts.closefd.cb) {
+ if ((error = so->opts.closefd.cb(fd, so->opts.closefd.arg))) {
+ return error;
+ } else if (*fd == -1)
+ return 0;
+ }
+
+ if (!(so->onum < so->olim)) {
+ unsigned olim = MAX(4, so->olim * 2);
+ void *old;
+
+ if (!(old = realloc(so->old, sizeof so->old[0] * olim)))
+ return dns_syerr();
+
+ so->old = old;
+ so->olim = olim;
+ }
+
+ so->old[so->onum++] = *fd;
+ *fd = -1;
+
+ return 0;
+} /* dns_so_closefd() */
+
+
+#define DNS_SO_CLOSE_UDP 0x01
+#define DNS_SO_CLOSE_TCP 0x02
+#define DNS_SO_CLOSE_OLD 0x04
+#define DNS_SO_CLOSE_ALL (DNS_SO_CLOSE_UDP|DNS_SO_CLOSE_TCP|DNS_SO_CLOSE_OLD)
+
+static void dns_so_closefds(struct dns_socket *so, int which) {
+ if (DNS_SO_CLOSE_UDP & which)
+ dns_socketclose(&so->udp);
+ if (DNS_SO_CLOSE_TCP & which)
+ dns_socketclose(&so->tcp);
+ if (DNS_SO_CLOSE_OLD & which) {
+ unsigned i;
+ for (i = 0; i < so->onum; i++)
+ dns_socketclose(&so->old[i]);
+ so->onum = 0;
+ free(so->old);
+ so->old = 0;
+ so->olim = 0;
+ }
+} /* dns_so_closefds() */
+
+
+static void dns_so_destroy(struct dns_socket *);
+
+static struct dns_socket *dns_so_init(struct dns_socket *so, const struct sockaddr *local, int type, const struct dns_options *opts, int *error) {
+ static const struct dns_socket so_initializer = { .opts = DNS_OPTS_INITIALIZER, .udp = -1, .tcp = -1, };
+
+ *so = so_initializer;
+ so->type = type;
+
+ if (opts)
+ so->opts = *opts;
+
+ if (local)
+ memcpy(&so->local, local, dns_sa_len(local));
+
+ if (-1 == (so->udp = dns_socket((struct sockaddr *)&so->local, SOCK_DGRAM, error)))
+ goto error;
+
+ dns_k_permutor_init(&so->qids, 1, 65535);
+
+ return so;
+error:
+ dns_so_destroy(so);
+
+ return 0;
+} /* dns_so_init() */
+
+
+struct dns_socket *dns_so_open(const struct sockaddr *local, int type, const struct dns_options *opts, int *error) {
+ struct dns_socket *so;
+
+ if (!(so = malloc(sizeof *so)))
+ goto syerr;
+
+ if (!dns_so_init(so, local, type, opts, error))
+ goto error;
+
+ return so;
+syerr:
+ *error = dns_syerr();
+error:
+ dns_so_close(so);
+
+ return 0;
+} /* dns_so_open() */
+
+
+static void dns_so_destroy(struct dns_socket *so) {
+ dns_so_reset(so);
+ dns_so_closefds(so, DNS_SO_CLOSE_ALL);
+} /* dns_so_destroy() */
+
+
+void dns_so_close(struct dns_socket *so) {
+ if (!so)
+ return;
+
+ dns_so_destroy(so);
+
+ free(so);
+} /* dns_so_close() */
+
+
+void dns_so_reset(struct dns_socket *so) {
+ free(so->answer);
+
+ memset(&so->state, '\0', sizeof *so - offsetof(struct dns_socket, state));
+} /* dns_so_reset() */
+
+
+unsigned short dns_so_mkqid(struct dns_socket *so) {
+ return dns_k_permutor_step(&so->qids);
+} /* dns_so_mkqid() */
+
+
+#define DNS_SO_MINBUF 768
+
+static int dns_so_newanswer(struct dns_socket *so, size_t len) {
+ size_t size = offsetof(struct dns_packet, data) + MAX(len, DNS_SO_MINBUF);
+ void *p;
+
+ if (!(p = realloc(so->answer, size)))
+ return dns_syerr();
+
+ so->answer = dns_p_init(p, size);
+
+ return 0;
+} /* dns_so_newanswer() */
+
+
+int dns_so_submit(struct dns_socket *so, struct dns_packet *Q, struct sockaddr *host) {
+ struct dns_rr rr;
+ int error = -1;
+
+ dns_so_reset(so);
+
+ if ((error = dns_rr_parse(&rr, 12, Q)))
+ goto error;
+
+ if (!(so->qlen = dns_d_expand(so->qname, sizeof so->qname, rr.dn.p, Q, &error)))
+ goto error;
+ /*
+ * NOTE: don't bail if expansion is too long; caller may be
+ * intentionally sending long names. However, we won't be able to
+ * verify it on return.
+ */
+
+ so->qtype = rr.type;
+ so->qclass = rr.class;
+
+ if ((error = dns_so_newanswer(so, DNS_SO_MINBUF)))
+ goto syerr;
+
+ memcpy(&so->remote, host, dns_sa_len(host));
+
+ so->query = Q;
+ so->qout = 0;
+ so->began = dns_now();
+
+ if (dns_header(so->query)->qid == 0)
+ dns_header(so->query)->qid = dns_so_mkqid(so);
+
+ so->qid = dns_header(so->query)->qid;
+ so->state = (so->type == SOCK_STREAM)? DNS_SO_TCP_INIT : DNS_SO_UDP_INIT;
+
+ so->stat.queries++;
+
+ return 0;
+syerr:
+ error = dns_syerr();
+error:
+ dns_so_reset(so);
+
+ return error;
+} /* dns_so_submit() */
+
+
+static int dns_so_verify(struct dns_socket *so, struct dns_packet *P) {
+ char qname[DNS_D_MAXNAME + 1];
+ size_t qlen;
+ struct dns_rr rr;
+ int error = -1;
+
+ if (so->qid != dns_header(so->answer)->qid)
+ return DNS_EUNKNOWN;
+
+ if (!dns_p_count(so->answer, DNS_S_QD))
+ return DNS_EUNKNOWN;
+
+ if (0 != dns_rr_parse(&rr, 12, so->answer))
+ return DNS_EUNKNOWN;
+
+ if (rr.type != so->qtype || rr.class != so->qclass)
+ return DNS_EUNKNOWN;
+
+ if (!(qlen = dns_d_expand(qname, sizeof qname, rr.dn.p, P, &error)))
+ return error;
+ else if (qlen >= sizeof qname || qlen != so->qlen)
+ return DNS_EUNKNOWN;
+
+ if (0 != strcasecmp(so->qname, qname))
+ return DNS_EUNKNOWN;
+
+ return 0;
+} /* dns_so_verify() */
+
+
+static int dns_so_tcp_send(struct dns_socket *so) {
+ unsigned char *qsrc;
+ size_t qend;
+ long n;
+
+ so->query->data[-2] = 0xff & (so->query->end >> 8);
+ so->query->data[-1] = 0xff & (so->query->end >> 0);
+
+ qsrc = &so->query->data[-2] + so->qout;
+ qend = so->query->end + 2;
+
+ while (so->qout < qend) {
+ if (0 > (n = send(so->tcp, (void *)&qsrc[so->qout], qend - so->qout, 0)))
+ return dns_soerr();
+
+ so->qout += n;
+ so->stat.tcp.sent.bytes += n;
+ }
+
+ so->stat.tcp.sent.count++;
+
+ return 0;
+} /* dns_so_tcp_send() */
+
+
+static int dns_so_tcp_recv(struct dns_socket *so) {
+ unsigned char *asrc;
+ size_t aend, alen;
+ int error;
+ long n;
+
+ aend = so->alen + 2;
+
+ while (so->apos < aend) {
+ asrc = &so->answer->data[-2];
+
+ if (0 > (n = recv(so->tcp, (void *)&asrc[so->apos], aend - so->apos, 0)))
+ return dns_soerr();
+ else if (n == 0)
+ return DNS_EUNKNOWN; /* FIXME */
+
+ so->apos += n;
+ so->stat.tcp.rcvd.bytes += n;
+
+ if (so->alen == 0 && so->apos >= 2) {
+ alen = ((0xff & so->answer->data[-2]) << 8)
+ | ((0xff & so->answer->data[-1]) << 0);
+
+ if ((error = dns_so_newanswer(so, alen)))
+ return error;
+
+ so->alen = alen;
+ aend = alen + 2;
+ }
+ }
+
+ so->answer->end = so->alen;
+ so->stat.tcp.rcvd.count++;
+
+ return 0;
+} /* dns_so_tcp_recv() */
+
+
+int dns_so_check(struct dns_socket *so) {
+ int error;
+ long n;
+
+retry:
+ switch (so->state) {
+ case DNS_SO_UDP_INIT:
+ so->state++;
+ case DNS_SO_UDP_CONN:
+ if (0 != connect(so->udp, (struct sockaddr *)&so->remote, dns_sa_len(&so->remote)))
+ goto soerr;
+
+ so->state++;
+ case DNS_SO_UDP_SEND:
+ if (0 > (n = send(so->udp, (void *)so->query->data, so->query->end, 0)))
+ goto soerr;
+
+ so->stat.udp.sent.bytes += n;
+ so->stat.udp.sent.count++;
+
+ so->state++;
+ case DNS_SO_UDP_RECV:
+ if (0 > (n = recv(so->udp, (void *)so->answer->data, so->answer->size, 0)))
+ goto soerr;
+
+ so->stat.udp.rcvd.bytes += n;
+ so->stat.udp.rcvd.count++;
+
+ if ((so->answer->end = n) < 12)
+ goto trash;
+
+ if ((error = dns_so_verify(so, so->answer)))
+ goto trash;
+
+ so->state++;
+ case DNS_SO_UDP_DONE:
+ if (!dns_header(so->answer)->tc || so->type == SOCK_DGRAM)
+ return 0;
+
+ so->state++;
+ case DNS_SO_TCP_INIT:
+ if ((error = dns_so_closefd(so, &so->tcp)))
+ goto error;
+
+ if (-1 == (so->tcp = dns_socket((struct sockaddr *)&so->local, SOCK_STREAM, &error)))
+ goto error;
+
+ so->state++;
+ case DNS_SO_TCP_CONN:
+ if (0 != connect(so->tcp, (struct sockaddr *)&so->remote, dns_sa_len(&so->remote))) {
+ if (dns_soerr() != DNS_EISCONN)
+ goto soerr;
+ }
+
+ so->state++;
+ case DNS_SO_TCP_SEND:
+ if ((error = dns_so_tcp_send(so)))
+ goto error;
+
+ so->state++;
+ case DNS_SO_TCP_RECV:
+ if ((error = dns_so_tcp_recv(so)))
+ goto error;
+
+ so->state++;
+ case DNS_SO_TCP_DONE:
+ if ((error = dns_so_closefd(so, &so->tcp)))
+ goto error;
+
+ if (so->answer->end < 12)
+ return DNS_EILLEGAL;
+
+ if ((error = dns_so_verify(so, so->answer)))
+ goto error;
+
+ return 0;
+ default:
+ error = DNS_EUNKNOWN;
+
+ goto error;
+ } /* switch() */
+
+trash:
+ goto retry;
+soerr:
+ error = dns_soerr();
+
+ goto error;
+error:
+ switch (error) {
+ case DNS_EINTR:
+ goto retry;
+ case DNS_EINPROGRESS:
+ /* FALL THROUGH */
+ case DNS_EALREADY:
+ /* FALL THROUGH */
+#if DNS_EWOULDBLOCK != DNS_EAGAIN
+ case DNS_EWOULDBLOCK:
+ /* FALL THROUGH */
+#endif
+ error = DNS_EAGAIN;
+
+ break;
+ } /* switch() */
+
+ return error;
+} /* dns_so_check() */
+
+
+struct dns_packet *dns_so_fetch(struct dns_socket *so, int *error) {
+ struct dns_packet *answer;
+
+ switch (so->state) {
+ case DNS_SO_UDP_DONE:
+ case DNS_SO_TCP_DONE:
+ answer = so->answer;
+ so->answer = 0;
+
+ return answer;
+ default:
+ *error = DNS_EUNKNOWN;
+
+ return 0;
+ }
+} /* dns_so_fetch() */
+
+
+struct dns_packet *dns_so_query(struct dns_socket *so, struct dns_packet *Q, struct sockaddr *host, int *error_) {
+ struct dns_packet *A;
+ int error;
+
+ if (!so->state) {
+ if ((error = dns_so_submit(so, Q, host)))
+ goto error;
+ }
+
+ if ((error = dns_so_check(so)))
+ goto error;
+
+ if (!(A = dns_so_fetch(so, &error)))
+ goto error;
+
+ dns_so_reset(so);
+
+ return A;
+error:
+ *error_ = error;
+
+ return 0;
+} /* dns_so_query() */
+
+
+time_t dns_so_elapsed(struct dns_socket *so) {
+ return dns_elapsed(so->began);
+} /* dns_so_elapsed() */
+
+
+void dns_so_clear(struct dns_socket *so) {
+ dns_so_closefds(so, DNS_SO_CLOSE_OLD);
+} /* dns_so_clear() */
+
+
+static int dns_so_events2(struct dns_socket *so, enum dns_events type) {
+ int events = 0;
+
+ switch (so->state) {
+ case DNS_SO_UDP_CONN:
+ case DNS_SO_UDP_SEND:
+ events |= DNS_POLLOUT;
+
+ break;
+ case DNS_SO_UDP_RECV:
+ events |= DNS_POLLIN;
+
+ break;
+ case DNS_SO_TCP_CONN:
+ case DNS_SO_TCP_SEND:
+ events |= DNS_POLLOUT;
+
+ break;
+ case DNS_SO_TCP_RECV:
+ events |= DNS_POLLIN;
+
+ break;
+ } /* switch() */
+
+ switch (type) {
+ case DNS_LIBEVENT:
+ return DNS_POLL2EV(events);
+ default:
+ return events;
+ } /* switch() */
+} /* dns_so_events2() */
+
+
+int dns_so_events(struct dns_socket *so) {
+ return dns_so_events2(so, so->opts.events);
+} /* dns_so_events() */
+
+
+int dns_so_pollfd(struct dns_socket *so) {
+ switch (so->state) {
+ case DNS_SO_UDP_CONN:
+ case DNS_SO_UDP_SEND:
+ case DNS_SO_UDP_RECV:
+ return so->udp;
+ case DNS_SO_TCP_CONN:
+ case DNS_SO_TCP_SEND:
+ case DNS_SO_TCP_RECV:
+ return so->tcp;
+ } /* switch() */
+
+ return -1;
+} /* dns_so_pollfd() */
+
+
+int dns_so_poll(struct dns_socket *so, int timeout) {
+ return dns_poll(dns_so_pollfd(so), dns_so_events2(so, DNS_SYSPOLL), timeout);
+} /* dns_so_poll() */
+
+
+const struct dns_stat *dns_so_stat(struct dns_socket *so) {
+ return &so->stat;
+} /* dns_so_stat() */
+
+
+/*
+ * R E S O L V E R R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+enum dns_res_state {
+ DNS_R_INIT,
+ DNS_R_GLUE,
+ DNS_R_SWITCH, /* (B)IND, (F)ILE, (C)ACHE */
+
+ DNS_R_FILE, /* Lookup in local hosts database */
+
+ DNS_R_CACHE, /* Lookup in application cache */
+ DNS_R_SUBMIT,
+ DNS_R_CHECK,
+ DNS_R_FETCH,
+
+ DNS_R_BIND, /* Lookup in the network */
+ DNS_R_SEARCH,
+ DNS_R_HINTS,
+ DNS_R_ITERATE,
+ DNS_R_FOREACH_NS,
+ DNS_R_RESOLV0_NS, /* Prologue: Setup next frame and recurse */
+ DNS_R_RESOLV1_NS, /* Epilog: Inspect answer */
+ DNS_R_FOREACH_A,
+ DNS_R_QUERY_A,
+ DNS_R_CNAME0_A,
+ DNS_R_CNAME1_A,
+
+ DNS_R_FINISH,
+ DNS_R_SMART0_A,
+ DNS_R_SMART1_A,
+ DNS_R_DONE,
+ DNS_R_SERVFAIL,
+}; /* enum dns_res_state */
+
+
+#define DNS_R_MAXDEPTH 8
+#define DNS_R_ENDFRAME (DNS_R_MAXDEPTH - 1)
+
+struct dns_resolver {
+ struct dns_socket so;
+
+ struct dns_resolv_conf *resconf;
+ struct dns_hosts *hosts;
+ struct dns_hints *hints;
+ struct dns_cache *cache;
+
+ dns_atomic_t refcount;
+
+ /* Reset zeroes everything below here. */
+
+ char qname[DNS_D_MAXNAME + 1];
+ size_t qlen;
+
+ enum dns_type qtype;
+ enum dns_class qclass;
+
+ time_t began;
+
+ dns_resconf_i_t search;
+
+ struct dns_rr_i smart;
+
+ struct dns_res_frame {
+ enum dns_res_state state;
+
+ int error;
+ int which; /* (B)IND, (F)ILE; index into resconf->lookup */
+
+ unsigned attempts;
+
+ struct dns_packet *query, *answer, *hints;
+
+ struct dns_rr_i hints_i, hints_j;
+ struct dns_rr hints_ns, ans_cname;
+ } stack[DNS_R_MAXDEPTH];
+
+ unsigned sp;
+}; /* struct dns_resolver */
+
+
+static int dns_res_tcp2type(int tcp) {
+ switch (tcp) {
+ case DNS_RESCONF_TCP_ONLY:
+ return SOCK_STREAM;
+ case DNS_RESCONF_TCP_DISABLE:
+ return SOCK_DGRAM;
+ default:
+ return 0;
+ }
+} /* dns_res_tcp2type() */
+
+struct dns_resolver *dns_res_open(struct dns_resolv_conf *resconf, struct dns_hosts *hosts, struct dns_hints *hints, struct dns_cache *cache, const struct dns_options *opts, int *error_) {
+ static const struct dns_resolver R_initializer
+ = { .refcount = 1, };
+ struct dns_resolver *R = 0;
+ int type, error;
+
+ /*
+ * Grab ref count early because the caller may have passed us a mortal
+ * reference, and we want to do the right thing if we return early
+ * from an error.
+ */
+ if (resconf)
+ dns_resconf_acquire(resconf);
+ if (hosts)
+ dns_hosts_acquire(hosts);
+ if (hints)
+ dns_hints_acquire(hints);
+ if (cache)
+ dns_cache_acquire(cache);
+
+ /*
+ * Don't try to load it ourselves because a NULL object might be an
+ * error from, say, dns_resconf_root(), and loading
+ * dns_resconf_local() by default would create undesirable surpises.
+ */
+ if (!resconf || !hosts || !hints)
+ goto error;
+
+ if (!(R = malloc(sizeof *R)))
+ goto syerr;
+
+ *R = R_initializer;
+ type = dns_res_tcp2type(resconf->options.tcp);
+
+ if (!dns_so_init(&R->so, (struct sockaddr *)&resconf->iface, type, opts, &error))
+ goto error;
+
+ R->resconf = resconf;
+ R->hosts = hosts;
+ R->hints = hints;
+ R->cache = cache;
+
+ return R;
+syerr:
+ error = dns_syerr();
+error:
+ *error_ = error;
+
+ dns_res_close(R);
+
+ dns_resconf_close(resconf);
+ dns_hosts_close(hosts);
+ dns_hints_close(hints);
+ dns_cache_close(cache);
+
+ return 0;
+} /* dns_res_open() */
+
+
+struct dns_resolver *dns_res_stub(const struct dns_options *opts, int *error) {
+ struct dns_resolv_conf *resconf = 0;
+ struct dns_hosts *hosts = 0;
+ struct dns_hints *hints = 0;
+ struct dns_resolver *res = 0;
+
+ if (!(resconf = dns_resconf_local(error)))
+ goto epilog;
+
+ if (!(hosts = dns_hosts_local(error)))
+ goto epilog;
+
+ if (!(hints = dns_hints_local(resconf, error)))
+ goto epilog;
+
+ if (!(res = dns_res_open(resconf, hosts, hints, NULL, opts, error)))
+ goto epilog;
+
+epilog:
+ dns_resconf_close(resconf);
+ dns_hosts_close(hosts);
+ dns_hints_close(hints);
+
+ return res;
+} /* dns_res_stub() */
+
+
+static void dns_res_reset_frame(struct dns_resolver *R __UNUSED__, struct dns_res_frame *frame) {
+ free(frame->query);
+ free(frame->answer);
+ free(frame->hints);
+
+ memset(frame, '\0', sizeof *frame);
+} /* dns_res_reset_frame() */
+
+
+void dns_res_reset(struct dns_resolver *R) {
+ unsigned i;
+
+ dns_so_reset(&R->so);
+
+ for (i = 0; i < lengthof(R->stack); i++)
+ dns_res_reset_frame(R, &R->stack[i]);
+
+ memset(&R->qname, '\0', sizeof *R - offsetof(struct dns_resolver, qname));
+} /* dns_res_reset() */
+
+
+void dns_res_close(struct dns_resolver *R) {
+ if (!R || 1 < dns_res_release(R))
+ return;
+
+ dns_res_reset(R);
+
+ dns_so_destroy(&R->so);
+
+ dns_hints_close(R->hints);
+ dns_hosts_close(R->hosts);
+ dns_resconf_close(R->resconf);
+ dns_cache_close(R->cache);
+
+ free(R);
+} /* dns_res_close() */
+
+
+unsigned dns_res_acquire(struct dns_resolver *R) {
+ return dns_atomic_inc(&R->refcount);
+} /* dns_res_acquire() */
+
+
+unsigned dns_res_release(struct dns_resolver *R) {
+ return dns_atomic_dec(&R->refcount);
+} /* dns_res_release() */
+
+
+struct dns_resolver *dns_res_mortal(struct dns_resolver *res) {
+ if (res)
+ dns_res_release(res);
+ return res;
+} /* dns_res_mortal() */
+
+
+static struct dns_packet *dns_res_merge(struct dns_packet *P0, struct dns_packet *P1, int *error_) {
+ size_t bufsiz = P0->end + P1->end;
+ struct dns_packet *P[3] = { P0, P1, 0 };
+ struct dns_rr rr[3];
+ int error, copy, i;
+ enum dns_section section;
+
+retry:
+ if (!(P[2] = dns_p_make(bufsiz, &error)))
+ goto error;
+
+ dns_rr_foreach(&rr[0], P[0], .section = DNS_S_QD) {
+ if ((error = dns_rr_copy(P[2], &rr[0], P[0])))
+ goto error;
+ }
+
+ for (section = DNS_S_AN; (DNS_S_ALL & section); section <<= 1) {
+ for (i = 0; i < 2; i++) {
+ dns_rr_foreach(&rr[i], P[i], .section = section) {
+ copy = 1;
+
+ dns_rr_foreach(&rr[2], P[2], .type = rr[i].type, .section = (DNS_S_ALL & ~DNS_S_QD)) {
+ if (0 == dns_rr_cmp(&rr[i], P[i], &rr[2], P[2])) {
+ copy = 0;
+
+ break;
+ }
+ }
+
+ if (copy && (error = dns_rr_copy(P[2], &rr[i], P[i]))) {
+ if (error == DNS_ENOBUFS && bufsiz < 65535) {
+ free(P[2]); P[2] = 0;
+
+ bufsiz = MAX(65535, bufsiz * 2);
+
+ goto retry;
+ }
+
+ goto error;
+ }
+ } /* foreach(rr) */
+ } /* foreach(packet) */
+ } /* foreach(section) */
+
+ return P[2];
+error:
+ *error_ = error;
+
+ free(P[2]);
+
+ return 0;
+} /* dns_res_merge() */
+
+
+static struct dns_packet *dns_res_glue(struct dns_resolver *R, struct dns_packet *Q) {
+ struct dns_packet *P = dns_p_new(512);
+ char qname[DNS_D_MAXNAME + 1];
+ size_t qlen;
+ enum dns_type qtype;
+ struct dns_rr rr;
+ unsigned sp;
+ int error;
+
+ if (!(qlen = dns_d_expand(qname, sizeof qname, 12, Q, &error))
+ || qlen >= sizeof qname)
+ return 0;
+
+ if (!(qtype = dns_rr_type(12, Q)))
+ return 0;
+
+ if ((error = dns_p_push(P, DNS_S_QD, qname, strlen(qname), qtype, DNS_C_IN, 0, 0)))
+ return 0;
+
+ for (sp = 0; sp <= R->sp; sp++) {
+ if (!R->stack[sp].answer)
+ continue;
+
+ dns_rr_foreach(&rr, R->stack[sp].answer, .name = qname, .type = qtype, .section = (DNS_S_ALL & ~DNS_S_QD)) {
+ rr.section = DNS_S_AN;
+
+ if ((error = dns_rr_copy(P, &rr, R->stack[sp].answer)))
+ return 0;
+ }
+ }
+
+ if (dns_p_count(P, DNS_S_AN) > 0)
+ goto copy;
+
+ /* Otherwise, look for a CNAME */
+ for (sp = 0; sp <= R->sp; sp++) {
+ if (!R->stack[sp].answer)
+ continue;
+
+ dns_rr_foreach(&rr, R->stack[sp].answer, .name = qname, .type = DNS_T_CNAME, .section = (DNS_S_ALL & ~DNS_S_QD)) {
+ rr.section = DNS_S_AN;
+
+ if ((error = dns_rr_copy(P, &rr, R->stack[sp].answer)))
+ return 0;
+ }
+ }
+
+ if (!dns_p_count(P, DNS_S_AN))
+ return 0;
+
+copy:
+ return dns_p_copy(dns_p_make(P->end, &error), P);
+} /* dns_res_glue() */
+
+
+static struct dns_packet *dns_res_mkquery(struct dns_resolver *R, const char *qname, enum dns_type qtype, enum dns_class qclass, int *error_) {
+ struct dns_packet *Q = 0;
+ int error;
+
+ if (!(Q = dns_p_init(malloc(DNS_P_QBUFSIZ), DNS_P_QBUFSIZ)))
+ goto syerr;
+
+ if ((error = dns_p_push(Q, DNS_S_QD, qname, strlen(qname), qtype, qclass, 0, 0)))
+ goto error;
+
+ dns_header(Q)->rd = !R->resconf->options.recurse;
+
+ return Q;
+syerr:
+ error = dns_syerr();
+error:
+ free(Q);
+
+ *error_ = error;
+
+ return 0;
+} /* dns_res_mkquery() */
+
+
+/*
+ * Sort NS records by three criteria:
+ *
+ * 1) Whether glue is present.
+ * 2) Whether glue record is original or of recursive lookup.
+ * 3) Randomly shuffle records which share the above criteria.
+ *
+ * NOTE: Assumes only NS records passed, AND ASSUMES no new NS records will
+ * be added during an iteration.
+ *
+ * FIXME: Only groks A glue, not AAAA glue.
+ */
+static int dns_res_nameserv_cmp(struct dns_rr *a, struct dns_rr *b, struct dns_rr_i *i, struct dns_packet *P) {
+ _Bool glued[2] = { 0 };
+ struct dns_ns ns;
+ struct dns_rr x, y;
+ int cmp, error;
+
+ if (!(error = dns_ns_parse(&ns, a, P)))
+ if (!(glued[0] = !!dns_rr_grep(&x, 1, dns_rr_i_new(P, .section = (DNS_S_ALL & ~DNS_S_QD), .name = ns.host, .type = DNS_T_A), P, &error)))
+ x.dn.p = 0;
+
+ if (!(error = dns_ns_parse(&ns, b, P)))
+ if (!(glued[1] = !!dns_rr_grep(&y, 1, dns_rr_i_new(P, .section = (DNS_S_ALL & ~DNS_S_QD), .name = ns.host, .type = DNS_T_A), P, &error)))
+ y.dn.p = 0;
+
+ if ((cmp = glued[1] - glued[0]))
+ return cmp;
+ else if ((cmp = (dns_rr_offset(&y) < i->args[0]) - (dns_rr_offset(&x) < i->args[0])))
+ return cmp;
+ else
+ return dns_rr_i_shuffle(a, b, i, P);
+} /* dns_res_nameserv_cmp() */
+
+
+#define goto(sp, i) \
+ do { R->stack[(sp)].state = (i); goto exec; } while (0)
+
+static int dns_res_exec(struct dns_resolver *R) {
+ struct dns_res_frame *F;
+ struct dns_packet *P;
+ char host[DNS_D_MAXNAME + 1];
+ size_t len;
+ struct dns_rr rr;
+ struct sockaddr_in sin;
+ int error;
+
+exec:
+
+ F = &R->stack[R->sp];
+
+ switch (F->state) {
+ case DNS_R_INIT:
+ F->state++;
+ case DNS_R_GLUE:
+ if (R->sp == 0)
+ goto(R->sp, DNS_R_SWITCH);
+
+ assert(F->query);
+
+ if (!(F->answer = dns_res_glue(R, F->query)))
+ goto(R->sp, DNS_R_SWITCH);
+
+ if (!(len = dns_d_expand(host, sizeof host, 12, F->query, &error)))
+ goto error;
+ else if (len >= sizeof host)
+ goto toolong;
+
+ dns_rr_foreach(&rr, F->answer, .name = host, .type = dns_rr_type(12, F->query), .section = DNS_S_AN) {
+ goto(R->sp, DNS_R_FINISH);
+ }
+
+ dns_rr_foreach(&rr, F->answer, .name = host, .type = DNS_T_CNAME, .section = DNS_S_AN) {
+ F->ans_cname = rr;
+
+ goto(R->sp, DNS_R_CNAME0_A);
+ }
+
+ F->state++;
+ case DNS_R_SWITCH:
+ while (F->which < (int)sizeof R->resconf->lookup) {
+ switch (R->resconf->lookup[F->which++]) {
+ case 'b': case 'B':
+ goto(R->sp, DNS_R_BIND);
+ case 'f': case 'F':
+ goto(R->sp, DNS_R_FILE);
+ case 'c': case 'C':
+ if (R->cache)
+ goto(R->sp, DNS_R_CACHE);
+
+ break;
+ default:
+ break;
+ }
+ }
+
+ goto(R->sp, DNS_R_SERVFAIL); /* FIXME: Right behavior? */
+ case DNS_R_FILE:
+ if (R->sp > 0) {
+ free(F->answer);
+
+ if (!(F->answer = dns_hosts_query(R->hosts, F->query, &error)))
+ goto error;
+
+ if (dns_p_count(F->answer, DNS_S_AN) > 0)
+ goto(R->sp, DNS_R_FINISH);
+
+ free(F->answer); F->answer = 0;
+ } else {
+ R->search = 0;
+
+ while ((len = dns_resconf_search(host, sizeof host, R->qname, R->qlen, R->resconf, &R->search))) {
+/*
+ * FIXME: Some sort of bug, either with this code or with GCC 3.3.5 on
+ * OpenBSD 4.4, overwites the stack guard. If the bug is in this file, it
+ * appears to be localized somewhere around here. It can also be mitigated
+ * in dns_hosts_query(). In any event, the bug manifests only when using
+ * compound literals. alloca(), malloc(), calloc(), etc, all work fine.
+ * Valgrind (tested on Linux) cannot detect any issues, but stack issues are
+ * not Valgrind's forte. Neither can I spot anything in the assembly, but
+ * that's not my forte.
+ */
+#if __OpenBSD__ && __GNUC__
+ struct dns_packet *query = __builtin_alloca(DNS_P_QBUFSIZ);
+
+ dns_p_init(query, DNS_P_QBUFSIZ);
+#else
+ struct dns_packet *query = dns_p_new(DNS_P_QBUFSIZ);
+#endif
+
+ if ((error = dns_p_push(query, DNS_S_QD, host, len, R->qtype, R->qclass, 0, 0)))
+ goto error;
+
+ free(F->answer);
+
+ if (!(F->answer = dns_hosts_query(R->hosts, query, &error)))
+ goto error;
+
+ if (dns_p_count(F->answer, DNS_S_AN) > 0)
+ goto(R->sp, DNS_R_FINISH);
+
+ free(F->answer); F->answer = 0;
+ }
+ }
+
+ goto(R->sp, DNS_R_SWITCH);
+ case DNS_R_CACHE:
+ error = 0;
+
+ if (!F->query && !(F->query = dns_res_mkquery(R, R->qname, R->qtype, R->qclass, &error)))
+ goto error;
+
+ free(F->answer);
+
+ if ((F->answer = R->cache->query(F->query, R->cache, &error))) {
+ if (dns_p_count(F->answer, DNS_S_AN) > 0)
+ goto(R->sp, DNS_R_FINISH);
+
+ free(F->answer); F->answer = 0;
+
+ goto(R->sp, DNS_R_SWITCH);
+ } else if (error)
+ goto error;
+
+ F->state++;
+ case DNS_R_SUBMIT:
+ if ((error = R->cache->submit(F->query, R->cache)))
+ goto error;
+
+ F->state++;
+ case DNS_R_CHECK:
+ if ((error = R->cache->check(R->cache)))
+ goto error;
+
+ F->state++;
+ case DNS_R_FETCH:
+ error = 0;
+
+ free(F->answer);
+
+ if ((F->answer = R->cache->fetch(R->cache, &error))) {
+ if (dns_p_count(F->answer, DNS_S_AN) > 0)
+ goto(R->sp, DNS_R_FINISH);
+
+ free(F->answer); F->answer = 0;
+
+ goto(R->sp, DNS_R_SWITCH);
+ } else if (error)
+ goto error;
+
+ goto(R->sp, DNS_R_SWITCH);
+ case DNS_R_BIND:
+ if (R->sp > 0) {
+ assert(F->query);
+
+ goto(R->sp, DNS_R_HINTS);
+ }
+
+ R->search = 0;
+
+ F->state++;
+ case DNS_R_SEARCH:
+ if (!(len = dns_resconf_search(host, sizeof host, R->qname, R->qlen, R->resconf, &R->search)))
+ goto(R->sp, DNS_R_SWITCH);
+
+ if (!(P = dns_p_make(DNS_P_QBUFSIZ, &error)))
+ goto error;
+
+ dns_header(P)->rd = !R->resconf->options.recurse;
+
+ free(F->query); F->query = P;
+
+ if ((error = dns_p_push(F->query, DNS_S_QD, host, len, R->qtype, R->qclass, 0, 0)))
+ goto error;
+
+ F->state++;
+ case DNS_R_HINTS:
+ if (!(F->hints = dns_hints_query(R->hints, F->query, &error)))
+ goto error;
+
+ F->state++;
+ case DNS_R_ITERATE:
+ dns_rr_i_init(&F->hints_i, F->hints);
+
+ F->hints_i.section = DNS_S_AUTHORITY;
+ F->hints_i.type = DNS_T_NS;
+ F->hints_i.sort = &dns_res_nameserv_cmp;
+ F->hints_i.args[0] = F->hints->end;
+
+ F->state++;
+ case DNS_R_FOREACH_NS:
+ dns_rr_i_save(&F->hints_i);
+
+ /* Load our next nameserver host. */
+ if (!dns_rr_grep(&F->hints_ns, 1, &F->hints_i, F->hints, &error)) {
+ if (++F->attempts < R->resconf->options.attempts)
+ goto(R->sp, DNS_R_ITERATE);
+
+ goto(R->sp, DNS_R_SWITCH);
+ }
+
+ dns_rr_i_init(&F->hints_j, F->hints);
+
+ /* Assume there are glue records */
+ goto(R->sp, DNS_R_FOREACH_A);
+ case DNS_R_RESOLV0_NS:
+ /* Have we reached our max depth? */
+ if (&F[1] >= endof(R->stack))
+ goto(R->sp, DNS_R_FOREACH_NS);
+
+ dns_res_reset_frame(R, &F[1]);
+
+ if (!(F[1].query = dns_p_make(DNS_P_QBUFSIZ, &error)))
+ goto error;
+
+ if ((error = dns_ns_parse((struct dns_ns *)host, &F->hints_ns, F->hints)))
+ goto error;
+
+ if ((error = dns_p_push(F[1].query, DNS_S_QD, host, strlen(host), DNS_T_A, DNS_C_IN, 0, 0)))
+ goto error;
+
+ F->state++;
+
+ goto(++R->sp, DNS_R_INIT);
+ case DNS_R_RESOLV1_NS:
+ if (!(len = dns_d_expand(host, sizeof host, 12, F[1].query, &error)))
+ goto error;
+ else if (len >= sizeof host)
+ goto toolong;
+
+ dns_rr_foreach(&rr, F[1].answer, .name = host, .type = DNS_T_A, .section = (DNS_S_ALL & ~DNS_S_QD)) {
+ rr.section = DNS_S_AR;
+
+ if ((error = dns_rr_copy(F->hints, &rr, F[1].answer)))
+ goto error;
+
+ dns_rr_i_rewind(&F->hints_i); /* Now there's glue. */
+ }
+
+ goto(R->sp, DNS_R_FOREACH_NS);
+ case DNS_R_FOREACH_A:
+ /*
+ * NOTE: Iterator initialized in DNS_R_FOREACH_NS because
+ * this state is re-entrant, but we need to reset
+ * .name to a valid pointer each time.
+ */
+ if ((error = dns_ns_parse((struct dns_ns *)host, &F->hints_ns, F->hints)))
+ goto error;
+
+ F->hints_j.name = host;
+ F->hints_j.type = DNS_T_A;
+ F->hints_j.section = DNS_S_ALL & ~DNS_S_QD;
+
+ if (!dns_rr_grep(&rr, 1, &F->hints_j, F->hints, &error)) {
+ if (!dns_rr_i_count(&F->hints_j))
+ goto(R->sp, DNS_R_RESOLV0_NS);
+
+ goto(R->sp, DNS_R_FOREACH_NS);
+ }
+
+ sin.sin_family = AF_INET;
+
+ if ((error = dns_a_parse((struct dns_a *)&sin.sin_addr, &rr, F->hints)))
+ goto error;
+
+ if (R->sp == 0)
+ sin.sin_port = dns_hints_port(R->hints, AF_INET, (struct sockaddr *)&sin.sin_addr);
+ else
+ sin.sin_port = htons(53);
+
+ if (DNS_DEBUG) {
+ char addr[INET_ADDRSTRLEN + 1];
+ dns_a_print(addr, sizeof addr, (struct dns_a *)&sin.sin_addr);
+ DNS_SHOW(F->query, "ASKING: %s/%s @ DEPTH: %u)", host, addr, R->sp);
+ }
+
+ if ((error = dns_so_submit(&R->so, F->query, (struct sockaddr *)&sin)))
+ goto error;
+
+ F->state++;
+ case DNS_R_QUERY_A:
+ if (dns_so_elapsed(&R->so) >= (time_t)R->resconf->options.timeout)
+ goto(R->sp, DNS_R_FOREACH_A);
+
+ if ((error = dns_so_check(&R->so)))
+ goto error;
+
+ free(F->answer);
+
+ if (!(F->answer = dns_so_fetch(&R->so, &error)))
+ goto error;
+
+ if (DNS_DEBUG) {
+ DNS_SHOW(F->answer, "ANSWER @ DEPTH: %u)", R->sp);
+ }
+
+ if ((error = dns_rr_parse(&rr, 12, F->query)))
+ goto error;
+
+ if (!(len = dns_d_expand(host, sizeof host, rr.dn.p, F->query, &error)))
+ goto error;
+ else if (len >= sizeof host)
+ goto toolong;
+
+ dns_rr_foreach(&rr, F->answer, .section = DNS_S_AN, .name = host, .type = rr.type) {
+ goto(R->sp, DNS_R_FINISH); /* Found */
+ }
+
+ dns_rr_foreach(&rr, F->answer, .section = DNS_S_AN, .name = host, .type = DNS_T_CNAME) {
+ F->ans_cname = rr;
+
+ goto(R->sp, DNS_R_CNAME0_A);
+ }
+
+ if (!R->resconf->options.recurse)
+ goto(R->sp, DNS_R_SWITCH);
+
+ dns_rr_foreach(&rr, F->answer, .section = DNS_S_NS, .type = DNS_T_NS) {
+ free(F->hints);
+
+ F->hints = F->answer;
+ F->answer = 0;
+
+ goto(R->sp, DNS_R_ITERATE);
+ }
+
+ /* XXX: Should this go further up? */
+ if (dns_header(F->answer)->aa)
+ goto(R->sp, DNS_R_FINISH);
+
+ goto(R->sp, DNS_R_FOREACH_A);
+ case DNS_R_CNAME0_A:
+ if (&F[1] >= endof(R->stack))
+ goto(R->sp, DNS_R_FINISH);
+
+ if ((error = dns_cname_parse((struct dns_cname *)host, &F->ans_cname, F->answer)))
+ goto error;
+
+ dns_res_reset_frame(R, &F[1]);
+
+ if (!(F[1].query = dns_p_make(DNS_P_QBUFSIZ, &error)))
+ goto error;
+
+ if ((error = dns_p_push(F[1].query, DNS_S_QD, host, strlen(host), dns_rr_type(12, F->query), DNS_C_IN, 0, 0)))
+ goto error;
+
+ F->state++;
+
+ goto(++R->sp, DNS_R_INIT);
+ case DNS_R_CNAME1_A:
+ if (!(P = dns_res_merge(F->answer, F[1].answer, &error)))
+ goto error;
+
+ free(F->answer); F->answer = P;
+
+ goto(R->sp, DNS_R_FINISH);
+ case DNS_R_FINISH:
+ assert(F->answer);
+
+ if (!R->resconf->options.smart || R->sp > 0)
+ goto(R->sp, DNS_R_DONE);
+
+ R->smart.section = DNS_S_AN;
+ R->smart.type = R->qtype;
+
+ dns_rr_i_init(&R->smart, F->answer);
+
+ F->state++;
+ case DNS_R_SMART0_A:
+ if (&F[1] >= endof(R->stack))
+ goto(R->sp, DNS_R_DONE);
+
+ while (dns_rr_grep(&rr, 1, &R->smart, F->answer, &error)) {
+ union {
+ struct dns_ns ns;
+ struct dns_mx mx;
+ struct dns_srv srv;
+ } rd;
+ const char *qname;
+ enum dns_type qtype;
+ enum dns_class qclass;
+
+ switch (rr.type) {
+ case DNS_T_NS:
+ if ((error = dns_ns_parse(&rd.ns, &rr, F->answer)))
+ goto error;
+
+ qname = rd.ns.host;
+ qtype = DNS_T_A;
+ qclass = DNS_C_IN;
+
+ break;
+ case DNS_T_MX:
+ if ((error = dns_mx_parse(&rd.mx, &rr, F->answer)))
+ goto error;
+
+ qname = rd.mx.host;
+ qtype = DNS_T_A;
+ qclass = DNS_C_IN;
+
+ break;
+ case DNS_T_SRV:
+ if ((error = dns_srv_parse(&rd.srv, &rr, F->answer)))
+ goto error;
+
+ qname = rd.srv.target;
+ qtype = DNS_T_A;
+ qclass = DNS_C_IN;
+
+ break;
+ default:
+ continue;
+ } /* switch() */
+
+ dns_res_reset_frame(R, &F[1]);
+
+ if (!(F[1].query = dns_res_mkquery(R, qname, qtype, qclass, &error)))
+ goto error;
+
+ F->state++;
+
+ goto(++R->sp, DNS_R_INIT);
+ } /* while() */
+
+ /*
+ * NOTE: SMTP specification says to fallback to A record.
+ *
+ * XXX: Should we add a mock MX answer?
+ */
+ if (R->qtype == DNS_T_MX && R->smart.state.count == 0) {
+ dns_res_reset_frame(R, &F[1]);
+
+ if (!(F[1].query = dns_res_mkquery(R, R->qname, DNS_T_A, DNS_C_IN, &error)))
+ goto error;
+
+ R->smart.state.count++;
+ F->state++;
+
+ goto(++R->sp, DNS_R_INIT);
+ }
+
+ goto(R->sp, DNS_R_DONE);
+ case DNS_R_SMART1_A:
+ assert(F[1].answer);
+
+ /*
+ * FIXME: For CNAME chains (which are typically illegal in
+ * this context), we should rewrite the record host name
+ * to the original smart qname. All the user cares about
+ * is locating that A/AAAA record.
+ */
+ dns_rr_foreach(&rr, F[1].answer, .section = DNS_S_AN, .type = DNS_T_A) {
+ rr.section = DNS_S_AR;
+
+ if (dns_rr_exists(&rr, F[1].answer, F->answer))
+ continue;
+
+ while ((error = dns_rr_copy(F->answer, &rr, F[1].answer))) {
+ if (error != DNS_ENOBUFS)
+ goto error;
+ if ((error = dns_p_grow(&F->answer)))
+ goto error;
+ }
+ }
+
+ goto(R->sp, DNS_R_SMART0_A);
+ case DNS_R_DONE:
+ assert(F->answer);
+
+ if (R->sp > 0)
+ goto(--R->sp, F[-1].state);
+
+ break;
+ case DNS_R_SERVFAIL:
+ free(F->answer);
+
+ if (!(F->answer = dns_p_make(DNS_P_QBUFSIZ, &error)))
+ goto error;
+
+ dns_header(F->answer)->qr = 1;
+ dns_header(F->answer)->rcode = DNS_RC_SERVFAIL;
+
+ if ((error = dns_p_push(F->answer, DNS_S_QD, R->qname, strlen(R->qname), R->qtype, R->qclass, 0, 0)))
+ goto error;
+
+ goto(R->sp, DNS_R_DONE);
+ default:
+ error = EINVAL;
+
+ goto error;
+ } /* switch () */
+
+ return 0;
+toolong:
+ error = DNS_EILLEGAL;
+error:
+ return error;
+} /* dns_res_exec() */
+
+#undef goto
+
+
+void dns_res_clear(struct dns_resolver *R) {
+ switch (R->stack[R->sp].state) {
+ case DNS_R_CHECK:
+ return R->cache->clear(R->cache);
+ default:
+ return dns_so_clear(&R->so);
+ }
+} /* dns_res_clear() */
+
+
+static int dns_res_events2(struct dns_resolver *R, enum dns_events type) {
+ int events;
+
+ switch (R->stack[R->sp].state) {
+ case DNS_R_CHECK:
+ events = R->cache->events(R->cache);
+
+ return (type == DNS_LIBEVENT)? DNS_POLL2EV(events) : events;
+ default:
+ return dns_so_events2(&R->so, type);
+ }
+} /* dns_res_events2() */
+
+
+int dns_res_events(struct dns_resolver *R) {
+ return dns_res_events2(R, R->so.opts.events);
+} /* dns_res_events() */
+
+
+int dns_res_pollfd(struct dns_resolver *R) {
+ switch (R->stack[R->sp].state) {
+ case DNS_R_CHECK:
+ return R->cache->pollfd(R->cache);
+ default:
+ return dns_so_pollfd(&R->so);
+ }
+} /* dns_res_pollfd() */
+
+
+time_t dns_res_elapsed(struct dns_resolver *R) {
+ return dns_elapsed(R->began);
+} /* dns_res_elapsed() */
+
+
+int dns_res_poll(struct dns_resolver *R, int timeout) {
+ return dns_poll(dns_res_pollfd(R), dns_res_events2(R, DNS_SYSPOLL), timeout);
+} /* dns_res_poll() */
+
+
+int dns_res_submit(struct dns_resolver *R, const char *qname, enum dns_type qtype, enum dns_class qclass) {
+ dns_res_reset(R);
+
+ /* Don't anchor; that can conflict with searchlist generation. */
+ dns_d_init(R->qname, sizeof R->qname, qname, (R->qlen = strlen(qname)), 0);
+
+ R->qtype = qtype;
+ R->qclass = qclass;
+
+ R->began = dns_now();
+
+ return 0;
+} /* dns_res_submit() */
+
+
+int dns_res_check(struct dns_resolver *R) {
+ int error;
+
+ if ((error = dns_res_exec(R)))
+ return error;
+
+ return 0;
+} /* dns_res_check() */
+
+
+struct dns_packet *dns_res_fetch(struct dns_resolver *R, int *error) {
+ struct dns_packet *answer;
+
+ if (R->stack[0].state != DNS_R_DONE) {
+ *error = DNS_EUNKNOWN;
+
+ return 0;
+ }
+
+ answer = R->stack[0].answer;
+ R->stack[0].answer = 0;
+
+ return answer;
+} /* dns_res_fetch() */
+
+
+struct dns_packet *dns_res_query(struct dns_resolver *res, const char *qname, enum dns_type qtype, enum dns_class qclass, int timeout, int *error_) {
+ int error;
+
+ if ((error = dns_res_submit(res, qname, qtype, qclass)))
+ goto error;
+
+ while ((error = dns_res_check(res))) {
+ if (dns_res_elapsed(res) > timeout)
+ error = DNS_ETIMEDOUT;
+
+ if (error != DNS_EAGAIN)
+ goto error;
+
+ if ((error = dns_res_poll(res, 1)))
+ goto error;
+ }
+
+ return dns_res_fetch(res, error_);
+error:
+ *error_ = error;
+
+ return 0;
+} /* dns_res_query() */
+
+
+const struct dns_stat *dns_res_stat(struct dns_resolver *res) {
+ return dns_so_stat(&res->so);
+} /* dns_res_stat() */
+
+
+/*
+ * A D D R I N F O R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+struct dns_addrinfo {
+ struct addrinfo hints;
+ struct dns_resolver *res;
+
+ char qname[DNS_D_MAXNAME + 1];
+ enum dns_type qtype;
+ unsigned short qport, port;
+
+ struct dns_packet *answer;
+ struct dns_packet *glue;
+
+ struct dns_rr_i i, g;
+ struct dns_rr rr;
+
+ char cname[DNS_D_MAXNAME + 1];
+
+ int state;
+}; /* struct dns_addrinfo */
+
+
+struct dns_addrinfo *dns_ai_open(const char *host, const char *serv, enum dns_type qtype, const struct addrinfo *hints, struct dns_resolver *res, int *error_) {
+ static const struct dns_addrinfo ai_initializer;
+ struct dns_addrinfo *ai;
+ int error;
+
+ if (!res)
+ return 0;
+
+ dns_res_acquire(res);
+
+ if (!(ai = malloc(sizeof *ai)))
+ goto syerr;
+
+ *ai = ai_initializer;
+ ai->hints = *hints;
+
+ ai->res = res;
+ res = 0;
+
+ if (sizeof ai->qname <= dns_strlcpy(ai->qname, host, sizeof ai->qname))
+ { error = ENAMETOOLONG; goto error; }
+
+ ai->qtype = qtype;
+ ai->qport = 0;
+
+ if (serv) {
+ while (isdigit((unsigned char)*serv)) {
+ ai->qport *= 10;
+ ai->qport += *serv++ - '0';
+ }
+ }
+
+ ai->port = ai->qport;
+
+ return ai;
+syerr:
+ error = dns_syerr();
+error:
+ *error_ = error;
+
+ dns_ai_close(ai);
+ dns_res_close(res);
+
+ return 0;
+} /* dns_ai_open() */
+
+
+void dns_ai_close(struct dns_addrinfo *ai) {
+ if (!ai)
+ return;
+
+ dns_res_close(ai->res);
+
+ if (ai->answer != ai->glue)
+ free(ai->glue);
+
+ free(ai->answer);
+ free(ai);
+} /* dns_ai_close() */
+
+
+static int dns_ai_setent(struct addrinfo **ent, union dns_any *any, enum dns_type type, struct dns_addrinfo *ai) {
+ struct sockaddr *saddr;
+ struct sockaddr_in sin;
+ struct sockaddr_in6 sin6;
+ const char *cname;
+ size_t clen;
+
+ switch (type) {
+ case DNS_T_A:
+ saddr = memset(&sin, '\0', sizeof sin);
+
+ sin.sin_family = AF_INET;
+ sin.sin_port = htons(ai->port);
+
+ memcpy(&sin.sin_addr, any, sizeof sin.sin_addr);
+
+ break;
+ case DNS_T_AAAA:
+ saddr = memset(&sin6, '\0', sizeof sin6);
+
+ sin6.sin6_family = AF_INET6;
+ sin6.sin6_port = htons(ai->port);
+
+ memcpy(&sin6.sin6_addr, any, sizeof sin6.sin6_addr);
+
+ break;
+ default:
+ return EINVAL;
+ } /* switch() */
+
+ if (ai->hints.ai_flags & AI_CANONNAME) {
+ cname = (*ai->cname)? ai->cname : ai->qname;
+ clen = strlen(cname);
+ } else {
+ cname = NULL;
+ clen = 0;
+ }
+
+ if (!(*ent = malloc(sizeof **ent + dns_sa_len(saddr) + ((ai->hints.ai_flags & AI_CANONNAME)? clen + 1 : 0))))
+ return dns_syerr();
+
+ memset(*ent, '\0', sizeof **ent);
+
+ (*ent)->ai_family = saddr->sa_family;
+ (*ent)->ai_socktype = ai->hints.ai_socktype;
+ (*ent)->ai_protocol = ai->hints.ai_protocol;
+
+ (*ent)->ai_addr = memcpy((unsigned char *)*ent + sizeof **ent, saddr, dns_sa_len(saddr));
+ (*ent)->ai_addrlen = dns_sa_len(saddr);
+
+ if (ai->hints.ai_flags & AI_CANONNAME)
+ (*ent)->ai_canonname = memcpy((unsigned char *)*ent + sizeof **ent + dns_sa_len(saddr), cname, clen + 1);
+
+ return 0;
+} /* dns_ai_setent() */
+
+
+enum dns_ai_state {
+ DNS_AI_S_INIT,
+ DNS_AI_S_NUMERIC,
+ DNS_AI_S_SUBMIT,
+ DNS_AI_S_CHECK,
+ DNS_AI_S_FETCH,
+ DNS_AI_S_FOREACH_I,
+ DNS_AI_S_FOREACH_G,
+ DNS_AI_S_SUBMIT_G,
+ DNS_AI_S_CHECK_G,
+ DNS_AI_S_FETCH_G,
+ DNS_AI_S_DONE,
+}; /* enum dns_ai_state */
+
+#define dns_ai_goto(which) do { ai->state = (which); goto exec; } while (0)
+
+int dns_ai_nextent(struct addrinfo **ent, struct dns_addrinfo *ai) {
+ struct dns_packet *ans, *glue;
+ struct dns_rr rr;
+ char qname[DNS_D_MAXNAME + 1];
+ union dns_any any;
+ size_t len;
+ int error;
+
+ *ent = 0;
+
+exec:
+
+ switch (ai->state) {
+ case DNS_AI_S_INIT:
+ ai->state++;
+ case DNS_AI_S_NUMERIC:
+ if (1 == dns_inet_pton(AF_INET, ai->qname, &any.a)) {
+ ai->state = DNS_AI_S_DONE;
+
+ return dns_ai_setent(ent, &any, DNS_T_A, ai);
+ }
+
+ if (1 == dns_inet_pton(AF_INET6, ai->qname, &any.aaaa)) {
+ ai->state = DNS_AI_S_DONE;
+
+ return dns_ai_setent(ent, &any, DNS_T_AAAA, ai);
+ }
+
+ if (ai->hints.ai_flags & AI_NUMERICHOST)
+ dns_ai_goto(DNS_AI_S_DONE);
+
+ ai->state++;
+ case DNS_AI_S_SUBMIT:
+ if ((error = dns_res_submit(ai->res, ai->qname, ai->qtype, DNS_C_IN)))
+ return error;
+
+ ai->state++;
+ case DNS_AI_S_CHECK:
+ if ((error = dns_res_check(ai->res)))
+ return error;
+
+ ai->state++;
+ case DNS_AI_S_FETCH:
+ if (!(ai->answer = dns_res_fetch(ai->res, &error)))
+ return error;
+
+ if ((error = dns_p_study(ai->answer)))
+ return error;
+
+ ai->glue = ai->answer;
+
+ dns_rr_i_init(&ai->i, ai->answer);
+
+ ai->i.section = DNS_S_AN;
+ ai->i.type = ai->qtype;
+ ai->i.sort = &dns_rr_i_order;
+
+ ai->state++;
+ case DNS_AI_S_FOREACH_I:
+ /* Search generator may have changed our qname. */
+ if (!(len = dns_d_expand(qname, sizeof qname, 12, ai->answer, &error)))
+ return error;
+ else if (len >= sizeof qname)
+ return DNS_EILLEGAL;
+
+ if (!dns_d_cname(ai->cname, sizeof ai->cname, qname, strlen(qname), ai->answer, &error))
+ return error;
+
+ ai->i.name = ai->cname;
+
+ if (!dns_rr_grep(&rr, 1, &ai->i, ai->answer, &error))
+ dns_ai_goto(DNS_AI_S_DONE);
+
+ if ((error = dns_any_parse(&any, &rr, ai->answer)))
+ return error;
+
+ ai->port = ai->qport;
+
+ switch (rr.type) {
+ case DNS_T_A:
+ case DNS_T_AAAA:
+ return dns_ai_setent(ent, &any, rr.type, ai);
+ default:
+ if (!dns_any_cname(ai->cname, sizeof ai->cname, &any, rr.type))
+ dns_ai_goto(DNS_AI_S_FOREACH_I);
+
+ /*
+ * Find the "real" canonical name. Some authorities
+ * publish aliases where an RFC defines a canonical
+ * name. We trust that the resolver followed any
+ * CNAME chains on it's own, regardless of whether
+ * the "smart" option is enabled.
+ */
+ if (!dns_d_cname(ai->cname, sizeof ai->cname, ai->cname, strlen(ai->cname), ai->answer, &error))
+ return error;
+
+ if (rr.type == DNS_T_SRV)
+ ai->port = any.srv.port;
+
+ break;
+ } /* switch() */
+
+ dns_rr_i_init(&ai->g, ai->glue);
+
+ ai->g.section = DNS_S_ALL & ~DNS_S_QD;
+ ai->g.name = ai->cname;
+ ai->g.type = (ai->hints.ai_family == AF_INET6)? DNS_T_AAAA : DNS_T_A;
+
+ ai->state++;
+ case DNS_AI_S_FOREACH_G:
+ if (!dns_rr_grep(&rr, 1, &ai->g, ai->glue, &error)) {
+ if (dns_rr_i_count(&ai->g) > 0)
+ dns_ai_goto(DNS_AI_S_FOREACH_I);
+ else
+ dns_ai_goto(DNS_AI_S_SUBMIT_G);
+ }
+
+ if ((error = dns_any_parse(&any, &rr, ai->glue)))
+ return error;
+
+ return dns_ai_setent(ent, &any, rr.type, ai);
+ case DNS_AI_S_SUBMIT_G:
+ if (dns_rr_grep(&rr, 1, dns_rr_i_new(ai->glue, .section = DNS_S_QD, .name = ai->g.name, .type = ai->g.type), ai->glue, &error))
+ dns_ai_goto(DNS_AI_S_FOREACH_I);
+
+ if ((error = dns_res_submit(ai->res, ai->g.name, ai->g.type, DNS_C_IN)))
+ return error;
+
+ ai->state++;
+ case DNS_AI_S_CHECK_G:
+ if ((error = dns_res_check(ai->res)))
+ return error;
+
+ ai->state++;
+ case DNS_AI_S_FETCH_G:
+ if (!(ans = dns_res_fetch(ai->res, &error)))
+ return error;
+
+ dns_p_study(ans);
+
+ glue = dns_p_merge(ai->glue, DNS_S_ALL, ans, DNS_S_ALL, &error);
+
+ free(ans);
+
+ if (!glue)
+ return error;
+
+ if (ai->glue != ai->answer)
+ free(ai->glue);
+
+ ai->glue = glue;
+
+ dns_rr_i_init(&ai->g, ai->glue);
+
+ /* ai->g.name should already point to ai->cname */
+ if (!dns_d_cname(ai->cname, sizeof ai->cname, ai->cname, strlen(ai->cname), ai->glue, &error))
+ dns_ai_goto(DNS_AI_S_FOREACH_I);
+
+ /* NOTE: Keep all the other iterator filters */
+
+ dns_ai_goto(DNS_AI_S_FOREACH_G);
+ case DNS_AI_S_DONE:
+ return ENOENT;
+ default:
+ return EINVAL;
+ } /* switch() */
+} /* dns_ai_nextent() */
+
+
+time_t dns_ai_elapsed(struct dns_addrinfo *ai) {
+ return dns_res_elapsed(ai->res);
+} /* dns_ai_elapsed() */
+
+
+void dns_ai_clear(struct dns_addrinfo *ai) {
+ return dns_res_clear(ai->res);
+} /* dns_ai_clear() */
+
+
+int dns_ai_events(struct dns_addrinfo *ai) {
+ return dns_res_events(ai->res);
+} /* dns_ai_events() */
+
+
+int dns_ai_pollfd(struct dns_addrinfo *ai) {
+ return dns_res_pollfd(ai->res);
+} /* dns_ai_pollfd() */
+
+
+int dns_ai_poll(struct dns_addrinfo *ai, int timeout) {
+ return dns_res_poll(ai->res, timeout);
+} /* dns_ai_poll() */
+
+
+size_t dns_ai_print(void *dst, size_t lim, struct addrinfo *ent, struct dns_addrinfo *ai) {
+ char addr[MAX(INET_ADDRSTRLEN, INET6_ADDRSTRLEN) + 1];
+ size_t cp = 0;
+
+ cp += dns__printstring(dst, lim, cp, "[ ");
+ cp += dns__printstring(dst, lim, cp, ai->qname);
+ cp += dns__printstring(dst, lim, cp, " IN ");
+ cp += dns__printstring(dst, lim, cp, dns_strtype(ai->qtype));
+ cp += dns__printstring(dst, lim, cp, " ]\n");
+
+ cp += dns__printstring(dst, lim, cp, ".ai_family = ");
+
+ switch (ent->ai_family) {
+ case AF_INET:
+ cp += dns__printstring(dst, lim, cp, "AF_INET");
+ break;
+ case AF_INET6:
+ cp += dns__printstring(dst, lim, cp, "AF_INET6");
+ break;
+ default:
+ cp += dns__print10(dst, lim, cp, ent->ai_family, 0);
+ break;
+ }
+
+ cp += dns__printchar(dst, lim, cp, '\n');
+
+ cp += dns__printstring(dst, lim, cp, ".ai_socktype = ");
+
+ switch (ent->ai_socktype) {
+ case SOCK_STREAM:
+ cp += dns__printstring(dst, lim, cp, "SOCK_STREAM");
+ break;
+ case SOCK_DGRAM:
+ cp += dns__printstring(dst, lim, cp, "SOCK_DGRAM");
+ break;
+ default:
+ cp += dns__print10(dst, lim, cp, ent->ai_socktype, 0);
+ break;
+ }
+
+ cp += dns__printchar(dst, lim, cp, '\n');
+
+ cp += dns__printstring(dst, lim, cp, ".ai_addr = [");
+
+ dns_inet_ntop(dns_sa_family(ent->ai_addr), dns_sa_addr(dns_sa_family(ent->ai_addr), ent->ai_addr), addr, sizeof addr);
+
+ cp += dns__printstring(dst, lim, cp, addr);
+ cp += dns__printstring(dst, lim, cp, "]:");
+
+ cp += dns__print10(dst, lim, cp, ntohs(*dns_sa_port(dns_sa_family(ent->ai_addr), ent->ai_addr)), 0);
+ cp += dns__printchar(dst, lim, cp, '\n');
+
+ cp += dns__printstring(dst, lim, cp, ".ai_canonname = ");
+ cp += dns__printstring(dst, lim, cp, (ent->ai_canonname)? ent->ai_canonname : "[NULL]");
+ cp += dns__printchar(dst, lim, cp, '\n');
+
+ dns__printnul(dst, lim, cp);
+
+ return cp;
+} /* dns_ai_print() */
+
+
+const struct dns_stat *dns_ai_stat(struct dns_addrinfo *ai) {
+ return dns_res_stat(ai->res);
+} /* dns_ai_stat() */
+
+
+/*
+ * M I S C E L L A N E O U S R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+static const struct {
+ char name[16];
+ enum dns_section type;
+} dns_sections[] = {
+ { "QUESTION", DNS_S_QUESTION },
+ { "QD", DNS_S_QUESTION },
+ { "ANSWER", DNS_S_ANSWER },
+ { "AN", DNS_S_ANSWER },
+ { "AUTHORITY", DNS_S_AUTHORITY },
+ { "NS", DNS_S_AUTHORITY },
+ { "ADDITIONAL", DNS_S_ADDITIONAL },
+ { "AR", DNS_S_ADDITIONAL },
+};
+
+const char *(dns_strsection)(enum dns_section section, void *dst, size_t lim) {
+ unsigned i, p = 0;
+
+ for (i = 0; i < lengthof(dns_sections); i++) {
+ if (dns_sections[i].type & section) {
+ if (p > 0)
+ p += dns__printchar(dst, lim, p, '|');
+
+ p += dns__printstring(dst, lim, p, dns_sections[i].name);
+
+ section &= ~dns_sections[i].type;
+ }
+ }
+
+ if (!p)
+ p += dns__print10(dst, lim, 0, (0xffff & section), 0);
+
+ dns__printnul(dst, lim, p);
+
+ return dst;
+} /* dns_strsection() */
+
+
+enum dns_section dns_isection(const char *src) {
+ enum dns_section section = 0;
+ char sbuf[128];
+ char *name, *next;
+ unsigned i;
+
+ dns_strlcpy(sbuf, src, sizeof sbuf);
+ next = sbuf;
+
+ while ((name = dns_strsep(&next, "|+, \t"))) {
+ for (i = 0; i < lengthof(dns_sections); i++) {
+ if (!strcasecmp(dns_sections[i].name, name)) {
+ section |= dns_sections[i].type;
+ break;
+ }
+ }
+ }
+
+ return section;
+} /* dns_isection() */
+
+
+static const struct {
+ char name[8];
+ enum dns_class type;
+} dns_classes[] = {
+ { "IN", DNS_C_IN },
+};
+
+const char *(dns_strclass)(enum dns_class type, void *dst, size_t lim) {
+ unsigned i;
+
+ for (i = 0; i < lengthof(dns_classes); i++) {
+ if (dns_classes[i].type == type) {
+ dns__printnul(dst, lim, dns__printstring(dst, lim, 0, dns_classes[i].name));
+
+ return dst;
+ }
+ }
+
+ dns__printnul(dst, lim, dns__print10(dst, lim, 0, (0xffff & type), 0));
+
+ return dst;
+} /* dns_strclass() */
+
+
+enum dns_class dns_iclass(const char *name) {
+ unsigned i;
+
+ for (i = 0; i < lengthof(dns_classes); i++) {
+ if (!strcasecmp(dns_classes[i].name, name))
+ return dns_classes[i].type;
+ }
+
+ return 0;
+} /* dns_iclass() */
+
+
+const char *(dns_strtype)(enum dns_type type, void *dst, size_t lim) {
+ unsigned i;
+
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (dns_rrtypes[i].type == type) {
+ dns__printnul(dst, lim, dns__printstring(dst, lim, 0, dns_rrtypes[i].name));
+
+ return dst;
+ }
+ }
+
+ dns__printnul(dst, lim, dns__print10(dst, lim, 0, (0xffff & type), 0));
+
+ return dst;
+} /* dns_strtype() */
+
+
+enum dns_type dns_itype(const char *type) {
+ unsigned i;
+
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (!strcasecmp(dns_rrtypes[i].name, type))
+ return dns_rrtypes[i].type;
+ }
+
+ return 0;
+} /* dns_itype() */
+
+
+static char dns_opcodes[16][16] = {
+ [DNS_OP_QUERY] = "QUERY",
+ [DNS_OP_IQUERY] = "IQUERY",
+ [DNS_OP_STATUS] = "STATUS",
+ [DNS_OP_NOTIFY] = "NOTIFY",
+ [DNS_OP_UPDATE] = "UPDATE",
+};
+
+const char *dns_stropcode(enum dns_opcode opcode) {
+ opcode &= 0xf;
+
+ if ('\0' == dns_opcodes[opcode][0])
+ dns__printnul(dns_opcodes[opcode], sizeof dns_opcodes[opcode], dns__print10(dns_opcodes[opcode], sizeof dns_opcodes[opcode], 0, opcode, 0));
+
+ return dns_opcodes[opcode];
+} /* dns_stropcode() */
+
+
+enum dns_opcode dns_iopcode(const char *name) {
+ unsigned opcode;
+
+ for (opcode = 0; opcode < lengthof(dns_opcodes); opcode++) {
+ if (!strcasecmp(name, dns_opcodes[opcode]))
+ return opcode;
+ }
+
+ return lengthof(dns_opcodes) - 1;
+} /* dns_iopcode() */
+
+
+static char dns_rcodes[16][16] = {
+ [DNS_RC_NOERROR] = "NOERROR",
+ [DNS_RC_FORMERR] = "FORMERR",
+ [DNS_RC_SERVFAIL] = "SERVFAIL",
+ [DNS_RC_NXDOMAIN] = "NXDOMAIN",
+ [DNS_RC_NOTIMP] = "NOTIMP",
+ [DNS_RC_REFUSED] = "REFUSED",
+ [DNS_RC_YXDOMAIN] = "YXDOMAIN",
+ [DNS_RC_YXRRSET] = "YXRRSET",
+ [DNS_RC_NXRRSET] = "NXRRSET",
+ [DNS_RC_NOTAUTH] = "NOTAUTH",
+ [DNS_RC_NOTZONE] = "NOTZONE",
+};
+
+const char *dns_strrcode(enum dns_rcode rcode) {
+ rcode &= 0xf;
+
+ if ('\0' == dns_rcodes[rcode][0])
+ dns__printnul(dns_rcodes[rcode], sizeof dns_rcodes[rcode], dns__print10(dns_rcodes[rcode], sizeof dns_rcodes[rcode], 0, rcode, 0));
+
+ return dns_rcodes[rcode];
+} /* dns_strrcode() */
+
+
+enum dns_rcode dns_ircode(const char *name) {
+ unsigned rcode;
+
+ for (rcode = 0; rcode < lengthof(dns_rcodes); rcode++) {
+ if (!strcasecmp(name, dns_rcodes[rcode]))
+ return rcode;
+ }
+
+ return lengthof(dns_rcodes) - 1;
+} /* dns_ircode() */
+
+
+/*
+ * C O M M A N D - L I N E / R E G R E S S I O N R O U T I N E S
+ *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+#if DNS_MAIN
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <ctype.h>
+
+#if _WIN32
+#include <getopt.h>
+#endif
+
+#if !_WIN32
+#include <err.h>
+#endif
+
+
+struct {
+ struct {
+ const char *path[8];
+ unsigned count;
+ } resconf;
+
+ struct {
+ const char *path[8];
+ unsigned count;
+ } hosts;
+
+ struct {
+ const char *path[8];
+ unsigned count;
+ } cache;
+
+ const char *qname;
+ enum dns_type qtype;
+
+ int (*sort)();
+
+ int verbose;
+} MAIN = {
+ .sort = &dns_rr_i_packet,
+};
+
+
+void hexdump(const unsigned char *src, size_t len, FILE *fp) {
+ static const unsigned char hex[] = "0123456789abcdef";
+ static const unsigned char tmpl[] = " | |\n";
+ unsigned char ln[sizeof tmpl];
+ const unsigned char *sp, *se;
+ unsigned char *h, *g;
+ unsigned i, n;
+
+ sp = src;
+ se = sp + len;
+
+ while (sp < se) {
+ memcpy(ln, tmpl, sizeof ln);
+
+ h = &ln[2];
+ g = &ln[53];
+
+ for (n = 0; n < 2; n++) {
+ for (i = 0; i < 8 && se - sp > 0; i++, sp++) {
+ h[0] = hex[0x0f & (*sp >> 4)];
+ h[1] = hex[0x0f & (*sp >> 0)];
+ h += 3;
+
+ *g++ = (isgraph(*sp))? *sp : '.';
+ }
+
+ h++;
+ }
+
+ fputs((char *)ln, fp);
+ }
+
+ return /* void */;
+} /* hexdump() */
+
+
+static void panic(const char *fmt, ...) {
+ va_list ap;
+
+ va_start(ap, fmt);
+
+#if _WIN32
+ vfprintf(stderr, fmt, ap);
+
+ exit(EXIT_FAILURE);
+#else
+ verrx(EXIT_FAILURE, fmt, ap);
+#endif
+} /* panic() */
+
+#define panic_(fn, ln, fmt, ...) \
+ panic(fmt "%0s", (fn), (ln), __VA_ARGS__)
+#define panic(...) \
+ panic_(__func__, __LINE__, "(%s:%d) " __VA_ARGS__, "")
+
+
+static void *grow(unsigned char *p, size_t size) {
+ void *tmp;
+
+ if (!(tmp = realloc(p, size)))
+ panic("realloc(%zu): %s", size, dns_strerror(errno));
+
+ return tmp;
+} /* grow() */
+
+
+static size_t add(size_t a, size_t b) {
+ if (~a < b)
+ panic("%zu + %zu: integer overflow", a, b);
+
+ return a + b;
+} /* add() */
+
+
+static size_t append(unsigned char **dst, size_t osize, const void *src, size_t len) {
+ size_t size = add(osize, len);
+
+ *dst = grow(*dst, size);
+ memcpy(*dst + osize, src, len);
+
+ return size;
+} /* append() */
+
+
+static size_t slurp(unsigned char **dst, size_t osize, FILE *fp, const char *path) {
+ size_t size = osize;
+ unsigned char buf[1024];
+ size_t count;
+
+ while ((count = fread(buf, 1, sizeof buf, fp)))
+ size = append(dst, size, buf, count);
+
+ if (ferror(fp))
+ panic("%s: %s", path, dns_strerror(errno));
+
+ return size;
+} /* slurp() */
+
+
+static struct dns_resolv_conf *resconf(void) {
+ static struct dns_resolv_conf *resconf;
+ const char *path;
+ unsigned i;
+ int error;
+
+ if (resconf)
+ return resconf;
+
+ if (!(resconf = dns_resconf_open(&error)))
+ panic("dns_resconf_open: %s", dns_strerror(error));
+
+ if (!MAIN.resconf.count)
+ MAIN.resconf.path[MAIN.resconf.count++] = "/etc/resolv.conf";
+
+ for (i = 0; i < MAIN.resconf.count; i++) {
+ path = MAIN.resconf.path[i];
+
+ if (0 == strcmp(path, "-"))
+ error = dns_resconf_loadfile(resconf, stdin);
+ else
+ error = dns_resconf_loadpath(resconf, path);
+
+ if (error)
+ panic("%s: %s", path, dns_strerror(error));
+ }
+
+ return resconf;
+} /* resconf() */
+
+
+static struct dns_hosts *hosts(void) {
+ static struct dns_hosts *hosts;
+ const char *path;
+ unsigned i;
+ int error;
+
+ if (hosts)
+ return hosts;
+
+ if (!MAIN.hosts.count) {
+ MAIN.hosts.path[MAIN.hosts.count++] = "/etc/hosts";
+
+ /* Explicitly test dns_hosts_local() */
+ if (!(hosts = dns_hosts_local(&error)))
+ panic("%s: %s", "/etc/hosts", dns_strerror(error));
+
+ return hosts;
+ }
+
+ if (!(hosts = dns_hosts_open(&error)))
+ panic("dns_hosts_open: %s", dns_strerror(error));
+
+ for (i = 0; i < MAIN.hosts.count; i++) {
+ path = MAIN.hosts.path[i];
+
+ if (0 == strcmp(path, "-"))
+ error = dns_hosts_loadfile(hosts, stdin);
+ else
+ error = dns_hosts_loadpath(hosts, path);
+
+ if (error)
+ panic("%s: %s", path, dns_strerror(error));
+ }
+
+ return hosts;
+} /* hosts() */
+
+
+#if DNS_CACHE
+#include "cache.h"
+
+struct dns_cache *cache(void) {
+ static struct cache *cache;
+ const char *path;
+ unsigned i;
+ int error;
+
+ if (cache)
+ return cache_resi(cache);
+ if (!MAIN.cache.count)
+ return NULL;
+
+ if (!(cache = cache_open(&error)))
+ panic("%s: %s", MAIN.cache.path[0], dns_strerror(error));
+
+ for (i = 0; i < MAIN.cache.count; i++) {
+ path = MAIN.cache.path[i];
+
+ if (!strcmp(path, "-")) {
+ if ((error = cache_loadfile(cache, stdin, NULL, 0)))
+ panic("%s: %s", path, dns_strerror(error));
+ } else if ((error = cache_loadpath(cache, path, NULL, 0)))
+ panic("%s: %s", path, dns_strerror(error));
+ }
+
+ return cache_resi(cache);
+} /* cache() */
+#else
+struct dns_cache *cache(void) { return NULL; }
+#endif
+
+
+static void print_packet(struct dns_packet *P, FILE *fp) {
+ dns_p_dump3(P, dns_rr_i_new(P, .sort = MAIN.sort), fp);
+
+ if (MAIN.verbose > 2)
+ hexdump(P->data, P->end, fp);
+} /* print_packet() */
+
+
+static int parse_packet(int argc, char *argv[]) {
+ struct dns_packet *P = dns_p_new(512);
+ struct dns_packet *Q = dns_p_new(512);
+ enum dns_section section;
+ struct dns_rr rr;
+ int error;
+ union dns_any any;
+ char pretty[sizeof any * 2];
+ size_t len;
+
+ P->end = fread(P->data, 1, P->size, stdin);
+
+ fputs(";; [HEADER]\n", stdout);
+ fprintf(stdout, ";; qr : %s(%d)\n", (dns_header(P)->qr)? "QUERY" : "RESPONSE", dns_header(P)->qr);
+ fprintf(stdout, ";; opcode : %s(%d)\n", dns_stropcode(dns_header(P)->opcode), dns_header(P)->opcode);
+ fprintf(stdout, ";; aa : %s(%d)\n", (dns_header(P)->aa)? "AUTHORITATIVE" : "NON-AUTHORITATIVE", dns_header(P)->aa);
+ fprintf(stdout, ";; tc : %s(%d)\n", (dns_header(P)->tc)? "TRUNCATED" : "NOT-TRUNCATED", dns_header(P)->tc);
+ fprintf(stdout, ";; rd : %s(%d)\n", (dns_header(P)->rd)? "RECURSION-DESIRED" : "RECURSION-NOT-DESIRED", dns_header(P)->rd);
+ fprintf(stdout, ";; ra : %s(%d)\n", (dns_header(P)->ra)? "RECURSION-ALLOWED" : "RECURSION-NOT-ALLOWED", dns_header(P)->ra);
+ fprintf(stdout, ";; rcode : %s(%d)\n", dns_strrcode(dns_header(P)->rcode), dns_header(P)->rcode);
+
+ section = 0;
+
+ dns_rr_foreach(&rr, P, .sort = MAIN.sort) {
+ if (section != rr.section)
+ fprintf(stdout, "\n;; [%s:%d]\n", dns_strsection(rr.section), dns_p_count(P, rr.section));
+
+ if ((len = dns_rr_print(pretty, sizeof pretty, &rr, P, &error)))
+ fprintf(stdout, "%s\n", pretty);
+
+ dns_rr_copy(Q, &rr, P);
+
+ section = rr.section;
+ }
+
+ fputs("; ; ; ; ; ; ; ;\n\n", stdout);
+
+ section = 0;
+
+#if 0
+ dns_rr_foreach(&rr, Q, .name = "ns8.yahoo.com.") {
+#else
+ struct dns_rr rrset[32];
+ struct dns_rr_i *rri = dns_rr_i_new(Q, .name = dns_d_new("ns8.yahoo.com", DNS_D_ANCHOR), .sort = MAIN.sort);
+ unsigned rrcount = dns_rr_grep(rrset, lengthof(rrset), rri, Q, &error);
+
+ for (unsigned i = 0; i < rrcount; i++) {
+ rr = rrset[i];
+#endif
+ if (section != rr.section)
+ fprintf(stdout, "\n;; [%s:%d]\n", dns_strsection(rr.section), dns_p_count(Q, rr.section));
+
+ if ((len = dns_rr_print(pretty, sizeof pretty, &rr, Q, &error)))
+ fprintf(stdout, "%s\n", pretty);
+
+ section = rr.section;
+ }
+
+ if (MAIN.verbose > 1) {
+ fprintf(stderr, "orig:%zu\n", P->end);
+ hexdump(P->data, P->end, stdout);
+
+ fprintf(stderr, "copy:%zu\n", Q->end);
+ hexdump(Q->data, Q->end, stdout);
+ }
+
+ return 0;
+} /* parse_packet() */
+
+
+static int parse_domain(int argc, char *argv[]) {
+ char *dn;
+
+ dn = (argc > 1)? argv[1] : "f.l.google.com";
+
+ printf("[%s]\n", dn);
+
+ dn = dns_d_new(dn);
+
+ do {
+ puts(dn);
+ } while (dns_d_cleave(dn, strlen(dn) + 1, dn, strlen(dn)));
+
+ return 0;
+} /* parse_domain() */
+
+
+static int expand_domain(int argc, char *argv[]) {
+ unsigned short rp = 0;
+ unsigned char *src = NULL;
+ unsigned char *dst;
+ struct dns_packet *pkt;
+ size_t lim = 0, len;
+ int error;
+
+ if (argv[1])
+ rp = atoi(argv[1]);
+
+ len = slurp(&src, 0, stdin, "-");
+
+ if (!(pkt = dns_p_make(len, &error)))
+ panic("malloc(%zu): %s", len, dns_strerror(error));
+
+ memcpy(pkt->data, src, len);
+ pkt->end = len;
+
+ lim = 1;
+ dst = grow(NULL, lim);
+
+ while (lim <= (len = dns_d_expand(dst, lim, rp, pkt, &error))) {
+ lim = add(len, 1);
+ dst = grow(dst, lim);
+ }
+
+ if (!len)
+ panic("expand: %s", dns_strerror(error));
+
+ fwrite(dst, 1, len, stdout);
+ fflush(stdout);
+
+ free(src);
+ free(dst);
+ free(pkt);
+
+ return 0;
+} /* expand_domain() */
+
+
+static int show_resconf(int argc, char *argv[]) {
+ unsigned i;
+
+ resconf(); /* load it */
+
+ fputs("; SOURCES\n", stdout);
+
+ for (i = 0; i < MAIN.resconf.count; i++)
+ fprintf(stdout, "; %s\n", MAIN.resconf.path[i]);
+
+ fputs(";\n", stdout);
+
+ dns_resconf_dump(resconf(), stdout);
+
+ return 0;
+} /* show_resconf() */
+
+
+static int show_hosts(int argc, char *argv[]) {
+ unsigned i;
+
+ hosts();
+
+ fputs("# SOURCES\n", stdout);
+
+ for (i = 0; i < MAIN.hosts.count; i++)
+ fprintf(stdout, "# %s\n", MAIN.hosts.path[i]);
+
+ fputs("#\n", stdout);
+
+ dns_hosts_dump(hosts(), stdout);
+
+ return 0;
+} /* show_hosts() */
+
+
+static int query_hosts(int argc, char *argv[]) {
+ struct dns_packet *Q = dns_p_new(512);
+ struct dns_packet *A;
+ char qname[DNS_D_MAXNAME + 1];
+ size_t qlen;
+ int error;
+
+ if (!MAIN.qname)
+ MAIN.qname = (argc > 1)? argv[1] : "localhost";
+ if (!MAIN.qtype)
+ MAIN.qtype = DNS_T_A;
+
+ hosts();
+
+ if (MAIN.qtype == DNS_T_PTR && !strstr(MAIN.qname, "arpa")) {
+ union { struct in_addr a; struct in6_addr a6; } addr;
+ int af = (strchr(MAIN.qname, ':'))? AF_INET6 : AF_INET;
+
+ if (1 != dns_inet_pton(af, MAIN.qname, &addr))
+ panic("%s: %s", MAIN.qname, dns_strerror(error));
+
+ qlen = dns_ptr_qname(qname, sizeof qname, af, &addr);
+ } else
+ qlen = dns__printstring(qname, sizeof qname, 0, MAIN.qname);
+
+ if ((error = dns_p_push(Q, DNS_S_QD, qname, qlen, MAIN.qtype, DNS_C_IN, 0, 0)))
+ panic("%s: %s", qname, dns_strerror(error));
+
+ if (!(A = dns_hosts_query(hosts(), Q, &error)))
+ panic("%s: %s", qname, dns_strerror(error));
+
+ print_packet(A, stdout);
+
+ free(A);
+
+ return 0;
+} /* query_hosts() */
+
+
+static int search_list(int argc, char *argv[]) {
+ const char *qname = (argc > 1)? argv[1] : "f.l.google.com";
+ unsigned long i = 0;
+ char name[DNS_D_MAXNAME + 1];
+
+ printf("[%s]\n", qname);
+
+ while (dns_resconf_search(name, sizeof name, qname, strlen(qname), resconf(), &i))
+ puts(name);
+
+ return 0;
+} /* search_list() */
+
+
+int permute_set(int argc, char *argv[]) {
+ unsigned lo, hi, i;
+ struct dns_k_permutor p;
+
+ hi = (--argc > 0)? atoi(argv[argc]) : 8;
+ lo = (--argc > 0)? atoi(argv[argc]) : 0;
+
+ fprintf(stderr, "[%u .. %u]\n", lo, hi);
+
+ dns_k_permutor_init(&p, lo, hi);
+
+ for (i = lo; i <= hi; i++)
+ fprintf(stdout, "%u\n", dns_k_permutor_step(&p));
+// printf("%u -> %u -> %u\n", i, dns_k_permutor_E(&p, i), dns_k_permutor_D(&p, dns_k_permutor_E(&p, i)));
+
+ return 0;
+} /* permute_set() */
+
+
+int shuffle_16(int argc, char *argv[]) {
+ unsigned n, r;
+
+ if (--argc > 0) {
+ n = 0xffff & atoi(argv[argc]);
+ r = (--argc > 0)? (unsigned)atoi(argv[argc]) : dns_random();
+
+ fprintf(stdout, "%hu\n", dns_k_shuffle16(n, r));
+ } else {
+ r = dns_random();
+
+ for (n = 0; n < 65536; n++)
+ fprintf(stdout, "%hu\n", dns_k_shuffle16(n, r));
+ }
+
+ return 0;
+} /* shuffle_16() */
+
+
+int dump_random(int argc, char *argv[]) {
+ unsigned char b[32];
+ unsigned i, j, n, r;
+
+ n = (argc > 1)? atoi(argv[1]) : 32;
+
+ while (n) {
+ i = 0;
+
+ do {
+ r = dns_random();
+
+ for (j = 0; j < sizeof r && i < n && i < sizeof b; i++, j++) {
+ b[i] = 0xff & r;
+ r >>= 8;
+ }
+ } while (i < n && i < sizeof b);
+
+ hexdump(b, i, stdout);
+
+ n -= i;
+ }
+
+ return 0;
+} /* dump_random() */
+
+
+static int send_query(int argc, char *argv[]) {
+ struct dns_packet *A, *Q = dns_p_new(512);
+ char host[INET6_ADDRSTRLEN + 1];
+ struct sockaddr_storage ss;
+ struct dns_socket *so;
+ int error, type;
+
+ if (argc > 1) {
+ ss.ss_family = (strchr(argv[1], ':'))? AF_INET6 : AF_INET;
+
+ if (1 != dns_inet_pton(ss.ss_family, argv[1], dns_sa_addr(ss.ss_family, &ss)))
+ panic("%s: invalid host address", argv[1]);
+
+ *dns_sa_port(ss.ss_family, &ss) = htons(53);
+ } else
+ memcpy(&ss, &resconf()->nameserver[0], dns_sa_len(&resconf()->nameserver[0]));
+
+ if (!dns_inet_ntop(ss.ss_family, dns_sa_addr(ss.ss_family, &ss), host, sizeof host))
+ panic("bad host address, or none provided");
+
+ if (!MAIN.qname)
+ MAIN.qname = "ipv6.google.com";
+ if (!MAIN.qtype)
+ MAIN.qtype = DNS_T_AAAA;
+
+ if ((error = dns_p_push(Q, DNS_S_QD, MAIN.qname, strlen(MAIN.qname), MAIN.qtype, DNS_C_IN, 0, 0)))
+ panic("dns_p_push: %s", dns_strerror(error));
+
+ dns_header(Q)->rd = 1;
+
+ if (strstr(argv[0], "udp"))
+ type = SOCK_DGRAM;
+ else if (strstr(argv[0], "tcp"))
+ type = SOCK_STREAM;
+ else
+ type = dns_res_tcp2type(resconf()->options.tcp);
+
+ fprintf(stderr, "querying %s for %s IN %s\n", host, MAIN.qname, dns_strtype(MAIN.qtype));
+
+ if (!(so = dns_so_open((struct sockaddr *)&resconf()->iface, type, dns_opts(), &error)))
+ panic("dns_so_open: %s", dns_strerror(error));
+
+ while (!(A = dns_so_query(so, Q, (struct sockaddr *)&ss, &error))) {
+ if (error != EAGAIN)
+ panic("dns_so_query: %s (%d)", dns_strerror(error), error);
+ if (dns_so_elapsed(so) > 10)
+ panic("query timed-out");
+
+ dns_so_poll(so, 1);
+ }
+
+ print_packet(A, stdout);
+
+ dns_so_close(so);
+
+ return 0;
+} /* send_query() */
+
+
+static int print_arpa(int argc, char *argv[]) {
+ const char *ip = (argc > 1)? argv[1] : "::1";
+ int af = (strchr(ip, ':'))? AF_INET6 : AF_INET;
+ union { struct in_addr a4; struct in6_addr a6; } addr;
+ char host[DNS_D_MAXNAME + 1];
+
+ if (1 != dns_inet_pton(af, ip, &addr) || 0 == dns_ptr_qname(host, sizeof host, af, &addr))
+ panic("%s: invalid address", ip);
+
+ fprintf(stdout, "%s\n", host);
+
+ return 0;
+} /* print_arpa() */
+
+
+static int show_hints(int argc, char *argv[]) {
+ struct dns_hints *(*load)(struct dns_resolv_conf *, int *);
+ const char *which, *how, *who;
+ struct dns_hints *hints;
+ int error;
+
+ which = (argc > 1)? argv[1] : "local";
+ how = (argc > 2)? argv[2] : "plain";
+ who = (argc > 3)? argv[3] : "google.com";
+
+ load = (0 == strcmp(which, "local"))
+ ? &dns_hints_local
+ : &dns_hints_root;
+
+ if (!(hints = load(resconf(), &error)))
+ panic("%s: %s", argv[0], dns_strerror(error));
+
+ if (0 == strcmp(how, "plain")) {
+ dns_hints_dump(hints, stdout);
+ } else {
+ struct dns_packet *query, *answer;
+
+ query = dns_p_new(512);
+
+ if ((error = dns_p_push(query, DNS_S_QUESTION, who, strlen(who), DNS_T_A, DNS_C_IN, 0, 0)))
+ panic("%s: %s", who, dns_strerror(error));
+
+ if (!(answer = dns_hints_query(hints, query, &error)))
+ panic("%s: %s", who, dns_strerror(error));
+
+ print_packet(answer, stdout);
+
+ free(answer);
+ }
+
+ dns_hints_close(hints);
+
+ return 0;
+} /* show_hints() */
+
+
+static int resolve_query(int argc, char *argv[]) {
+ struct dns_hints *(*hints)() = (strstr(argv[0], "recurse"))? &dns_hints_root : &dns_hints_local;
+ struct dns_resolver *R;
+ struct dns_packet *ans;
+ const struct dns_stat *st;
+ int error;
+
+ if (!MAIN.qname)
+ MAIN.qname = "www.google.com";
+ if (!MAIN.qtype)
+ MAIN.qtype = DNS_T_A;
+
+ resconf()->options.recurse = (0 != strstr(argv[0], "recurse"));
+
+ if (!(R = dns_res_open(resconf(), hosts(), dns_hints_mortal(hints(resconf(), &error)), cache(), dns_opts(), &error)))
+ panic("%s: %s", MAIN.qname, dns_strerror(error));
+
+ if ((error = dns_res_submit(R, MAIN.qname, MAIN.qtype, DNS_C_IN)))
+ panic("%s: %s", MAIN.qname, dns_strerror(error));
+
+ while ((error = dns_res_check(R))) {
+ if (error != EAGAIN)
+ panic("dns_res_check: %s (%d)", dns_strerror(error), error);
+ if (dns_res_elapsed(R) > 30)
+ panic("query timed-out");
+
+ dns_res_poll(R, 1);
+ }
+
+ ans = dns_res_fetch(R, &error);
+ print_packet(ans, stdout);
+ free(ans);
+
+ st = dns_res_stat(R);
+ putchar('\n');
+ printf(";; queries: %zu\n", st->queries);
+ printf(";; udp sent: %zu in %zu bytes\n", st->udp.sent.count, st->udp.sent.bytes);
+ printf(";; udp rcvd: %zu in %zu bytes\n", st->udp.rcvd.count, st->udp.rcvd.bytes);
+ printf(";; tcp sent: %zu in %zu bytes\n", st->tcp.sent.count, st->tcp.sent.bytes);
+ printf(";; tcp rcvd: %zu in %zu bytes\n", st->tcp.rcvd.count, st->tcp.rcvd.bytes);
+
+ dns_res_close(R);
+
+ return 0;
+} /* resolve_query() */
+
+
+static int resolve_addrinfo(int argc, char *argv[]) {
+ struct dns_hints *(*hints)() = (strstr(argv[0], "recurse"))? &dns_hints_root : &dns_hints_local;
+ struct dns_resolver *res = 0;
+ struct dns_addrinfo *ai = 0;
+ struct addrinfo ai_hints = { .ai_family = PF_UNSPEC, .ai_socktype = SOCK_STREAM, .ai_flags = AI_CANONNAME };
+ struct addrinfo *ent;
+ char pretty[512];
+ int error;
+
+ if (!MAIN.qname)
+ MAIN.qname = "www.google.com";
+ if (!MAIN.qtype)
+ MAIN.qtype = DNS_T_A;
+
+ resconf()->options.recurse = (0 != strstr(argv[0], "recurse"));
+
+ if (!(res = dns_res_open(resconf(), hosts(), dns_hints_mortal(hints(resconf(), &error)), cache(), dns_opts(), &error)))
+ panic("%s: %s", MAIN.qname, dns_strerror(error));
+
+ if (!(ai = dns_ai_open(MAIN.qname, "80", MAIN.qtype, &ai_hints, res, &error)))
+ panic("%s: %s", MAIN.qname, dns_strerror(error));
+
+ do {
+ switch (error = dns_ai_nextent(&ent, ai)) {
+ case 0:
+ dns_ai_print(pretty, sizeof pretty, ent, ai);
+
+ fputs(pretty, stdout);
+
+ free(ent);
+
+ break;
+ case ENOENT:
+ break;
+ case EAGAIN:
+ if (dns_ai_elapsed(ai) > 30)
+ panic("query timed-out");
+
+ dns_ai_poll(ai, 1);
+
+ break;
+ default:
+ panic("dns_ai_nextent: %s (%d)", dns_strerror(error), error);
+ }
+ } while (error != ENOENT);
+
+ dns_res_close(res);
+ dns_ai_close(ai);
+
+ return 0;
+} /* resolve_addrinfo() */
+
+
+static int echo_port(int argc, char *argv[]) {
+ union {
+ struct sockaddr sa;
+ struct sockaddr_in sin;
+ } port;
+ int fd;
+
+ memset(&port, 0, sizeof port);
+ port.sin.sin_family = AF_INET;
+ port.sin.sin_port = htons(5354);
+ port.sin.sin_addr.s_addr = inet_addr("127.0.0.1");
+
+ if (-1 == (fd = socket(PF_INET, SOCK_DGRAM, 0)))
+ panic("socket: %s", strerror(errno));
+
+ if (0 != bind(fd, &port.sa, sizeof port.sa))
+ panic("127.0.0.1:5353: %s", dns_strerror(errno));
+
+ for (;;) {
+ struct dns_packet *pkt = dns_p_new(512);
+ struct sockaddr_storage ss;
+ socklen_t slen = sizeof ss;
+ ssize_t count;
+#if defined(MSG_WAITALL) /* MinGW issue */
+ int rflags = MSG_WAITALL;
+#else
+ int rflags = 0;
+#endif
+
+ count = recvfrom(fd, (char *)pkt->data, pkt->size, rflags, (struct sockaddr *)&ss, &slen);
+
+
+ if (!count || count < 0)
+ panic("recvfrom: %s", strerror(errno));
+
+ pkt->end = count;
+
+ dns_p_dump(pkt, stdout);
+
+ (void)sendto(fd, (char *)pkt->data, pkt->end, 0, (struct sockaddr *)&ss, slen);
+ }
+
+ return 0;
+} /* echo_port() */
+
+
+static int isection(int argc, char *argv[]) {
+ const char *name = (argv[1])? argv[1] : "";
+ int type;
+
+ type = dns_isection(name);
+ name = dns_strsection(type);
+
+ printf("%s (%d)\n", name, type);
+
+ return 0;
+} /* isection() */
+
+
+static int iclass(int argc, char *argv[]) {
+ const char *name = (argv[1])? argv[1] : "";
+ int type;
+
+ type = dns_iclass(name);
+ name = dns_strclass(type);
+
+ printf("%s (%d)\n", name, type);
+
+ return 0;
+} /* iclass() */
+
+
+static int itype(int argc, char *argv[]) {
+ const char *name = (argv[1])? argv[1] : "";
+ int type;
+
+ type = dns_itype(name);
+ name = dns_strtype(type);
+
+ printf("%s (%d)\n", name, type);
+
+ return 0;
+} /* itype() */
+
+
+static int iopcode(int argc, char *argv[]) {
+ const char *name = (argv[1])? argv[1] : "";
+ int type;
+
+ type = dns_iopcode(name);
+ name = dns_stropcode(type);
+
+ printf("%s (%d)\n", name, type);
+
+ return 0;
+} /* iopcode() */
+
+
+static int ircode(int argc, char *argv[]) {
+ const char *name = (argv[1])? argv[1] : "";
+ int type;
+
+ type = dns_ircode(name);
+ name = dns_strrcode(type);
+
+ printf("%s (%d)\n", name, type);
+
+ return 0;
+} /* ircode() */
+
+
+#define SIZE1(x) { DNS_PP_STRINGIFY(x), sizeof (x) }
+#define SIZE2(x, ...) SIZE1(x), SIZE1(__VA_ARGS__)
+#define SIZE3(x, ...) SIZE1(x), SIZE2(__VA_ARGS__)
+#define SIZE4(x, ...) SIZE1(x), SIZE3(__VA_ARGS__)
+#define SIZE(...) DNS_PP_CALL(DNS_PP_XPASTE(SIZE, DNS_PP_NARG(__VA_ARGS__)), __VA_ARGS__)
+
+static int sizes(int argc, char *argv[]) {
+ static const struct { const char *name; size_t size; } type[] = {
+ SIZE(struct dns_header, struct dns_packet, struct dns_rr, struct dns_rr_i),
+ SIZE(struct dns_a, struct dns_aaaa, struct dns_mx, struct dns_ns),
+ SIZE(struct dns_cname, struct dns_soa, struct dns_ptr, struct dns_srv),
+ SIZE(struct dns_sshfp, struct dns_txt, union dns_any),
+ SIZE(struct dns_resolv_conf, struct dns_hosts, struct dns_hints, struct dns_hints_i),
+ SIZE(struct dns_options, struct dns_socket, struct dns_resolver, struct dns_addrinfo),
+ SIZE(struct dns_cache),
+ };
+ unsigned i, max;
+
+ for (i = 0, max = 0; i < lengthof(type); i++)
+ max = MAX(max, strlen(type[i].name));
+
+ for (i = 0; i < lengthof(type); i++)
+ printf("%*s : %zu\n", max, type[i].name, type[i].size);
+
+ return 0;
+} /* sizes() */
+
+
+static const struct { const char *cmd; int (*run)(); const char *help; } cmds[] = {
+ { "parse-packet", &parse_packet, "parse binary packet from stdin" },
+ { "parse-domain", &parse_domain, "anchor and iteratively cleave domain" },
+ { "expand-domain", &expand_domain, "expand domain at offset NN in packet from stdin" },
+ { "show-resconf", &show_resconf, "show resolv.conf data" },
+ { "show-hosts", &show_hosts, "show hosts data" },
+ { "query-hosts", &query_hosts, "query A, AAAA or PTR in hosts data" },
+ { "search-list", &search_list, "generate query search list from domain" },
+ { "permute-set", &permute_set, "generate random permutation -> (0 .. N or N .. M)" },
+ { "shuffle-16", &shuffle_16, "simple 16-bit permutation" },
+ { "dump-random", &dump_random, "generate random bytes" },
+ { "send-query", &send_query, "send query to host" },
+ { "send-query-udp", &send_query, "send udp query to host" },
+ { "send-query-tcp", &send_query, "send tcp query to host" },
+ { "print-arpa", &print_arpa, "print arpa. zone name of address" },
+ { "show-hints", &show_hints, "print hints: show-hints [local|root] [plain|packet]" },
+ { "resolve-stub", &resolve_query, "resolve as stub resolver" },
+ { "resolve-recurse", &resolve_query, "resolve as recursive resolver" },
+ { "addrinfo-stub", &resolve_addrinfo, "resolve through getaddrinfo clone" },
+ { "addrinfo-recurse", &resolve_addrinfo, "resolve through getaddrinfo clone" },
+/* { "resolve-nameinfo", &resolve_query, "resolve as recursive resolver" }, */
+ { "echo", &echo_port, "server echo mode, for nmap fuzzing" },
+ { "isection", &isection, "parse section string" },
+ { "iclass", &iclass, "parse class string" },
+ { "itype", &itype, "parse type string" },
+ { "iopcode", &iopcode, "parse opcode string" },
+ { "ircode", &ircode, "parse rcode string" },
+ { "sizes", &sizes, "print data structure sizes" },
+};
+
+
+static void print_usage(const char *progname, FILE *fp) {
+ static const char *usage =
+ " [OPTIONS] COMMAND [ARGS]\n"
+ " -c PATH Path to resolv.conf\n"
+ " -l PATH Path to local hosts\n"
+ " -z PATH Path to zone cache\n"
+ " -q QNAME Query name\n"
+ " -t QTYPE Query type\n"
+ " -s HOW Sort records\n"
+ " -v Be more verbose (-vv show packets; -vvv hexdump packets)\n"
+ " -V Print version info\n"
+ " -h Print this usage message\n"
+ "\n";
+ unsigned i, n, m;
+
+ fputs(progname, fp);
+ fputs(usage, fp);
+
+ for (i = 0, m = 0; i < lengthof(cmds); i++) {
+ if (strlen(cmds[i].cmd) > m)
+ m = strlen(cmds[i].cmd);
+ }
+
+ for (i = 0; i < lengthof(cmds); i++) {
+ fprintf(fp, " %s ", cmds[i].cmd);
+
+ for (n = strlen(cmds[i].cmd); n < m; n++)
+ putc(' ', fp);
+
+ fputs(cmds[i].help, fp);
+ putc('\n', fp);
+ }
+
+ fputs("\nReport bugs to William Ahern <william@25thandClement.com>\n", fp);
+} /* print_usage() */
+
+
+static void print_version(const char *progname, FILE *fp) {
+ fprintf(fp, "%s (dns.c) %.8X\n", progname, dns_v_rel());
+ fprintf(fp, "vendor %s\n", dns_vendor());
+ fprintf(fp, "release %.8X\n", dns_v_rel());
+ fprintf(fp, "abi %.8X\n", dns_v_abi());
+ fprintf(fp, "api %.8X\n", dns_v_api());
+} /* print_version() */
+
+
+int main(int argc, char **argv) {
+ extern int optind;
+ extern char *optarg;
+ const char *progname = argv[0];
+ unsigned i;
+ int ch;
+
+ while (-1 != (ch = getopt(argc, argv, "q:t:c:l:z:s:vVh"))) {
+ switch (ch) {
+ case 'c':
+ assert(MAIN.resconf.count < lengthof(MAIN.resconf.path));
+
+ MAIN.resconf.path[MAIN.resconf.count++] = optarg;
+
+ break;
+ case 'l':
+ assert(MAIN.hosts.count < lengthof(MAIN.hosts.path));
+
+ MAIN.hosts.path[MAIN.hosts.count++] = optarg;
+
+ break;
+ case 'z':
+ assert(MAIN.cache.count < lengthof(MAIN.cache.path));
+
+ MAIN.cache.path[MAIN.cache.count++] = optarg;
+
+ break;
+ case 'q':
+ MAIN.qname = optarg;
+
+ break;
+ case 't':
+ for (i = 0; i < lengthof(dns_rrtypes); i++) {
+ if (0 == strcasecmp(dns_rrtypes[i].name, optarg))
+ { MAIN.qtype = dns_rrtypes[i].type; break; }
+ }
+
+ if (MAIN.qtype)
+ break;
+
+ for (i = 0; isdigit((int)optarg[i]); i++) {
+ MAIN.qtype *= 10;
+ MAIN.qtype += optarg[i] - '0';
+ }
+
+ if (!MAIN.qtype)
+ panic("%s: invalid query type", optarg);
+
+ break;
+ case 's':
+ if (0 == strcasecmp(optarg, "packet"))
+ MAIN.sort = &dns_rr_i_packet;
+ else if (0 == strcasecmp(optarg, "shuffle"))
+ MAIN.sort = &dns_rr_i_shuffle;
+ else if (0 == strcasecmp(optarg, "order"))
+ MAIN.sort = &dns_rr_i_order;
+ else
+ panic("%s: invalid sort method", optarg);
+
+ break;
+ case 'v':
+ dns_debug = ++MAIN.verbose;
+
+ break;
+ case 'V':
+ print_version(progname, stdout);
+
+ return 0;
+ case 'h':
+ print_usage(progname, stdout);
+
+ return 0;
+ default:
+ print_usage(progname, stderr);
+
+ return EXIT_FAILURE;
+ } /* switch() */
+ } /* while() */
+
+ argc -= optind;
+ argv += optind;
+
+ for (i = 0; i < lengthof(cmds) && argv[0]; i++) {
+ if (0 == strcmp(cmds[i].cmd, argv[0]))
+ return cmds[i].run(argc, argv);
+ }
+
+ print_usage(progname, stderr);
+
+ return EXIT_FAILURE;
+} /* main() */
+
+
+#endif /* DNS_MAIN */
projects / framework / uifw / ecore.git / commitdiff