1 /* ==========================================================================
2 * dns.h - Recursive, Reentrant DNS Resolver.
3 * --------------------------------------------------------------------------
4 * Copyright (c) 2009, 2010, 2012-2015 William Ahern
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sublicense, and/or sell copies of the Software, and to permit
11 * persons to whom the Software is furnished to do so, subject to the
12 * following conditions:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
20 * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
21 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
22 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
23 * USE OR OTHER DEALINGS IN THE SOFTWARE.
24 * ==========================================================================
29 #include <stddef.h> /* size_t offsetof() */
30 #include <stdint.h> /* uint64_t */
31 #include <stdio.h> /* FILE */
32 #include <string.h> /* strlen(3) */
33 #include <time.h> /* struct timespec time_t */
39 #include <sys/param.h> /* BYTE_ORDER BIG_ENDIAN _BIG_ENDIAN */
40 #include <sys/types.h> /* socklen_t */
41 #include <sys/socket.h> /* struct socket */
42 #include <poll.h> /* POLLIN POLLOUT */
43 #include <netinet/in.h> /* struct in_addr struct in6_addr */
44 #include <netdb.h> /* struct addrinfo */
51 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
61 * Vendor: Entity for which versions numbers are relevant. (If forking
62 * change DNS_VENDOR to avoid confusion.)
66 * REL Official "release"--bug fixes, new features, etc.
67 * ABI Changes to existing object sizes or parameter types
68 * API Changes that might effect application source.
70 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
72 #define DNS_VENDOR "william@25thandClement.com"
74 #define DNS_V_REL 0x20160809
75 #define DNS_V_ABI 0x20160608
76 #define DNS_V_API 0x20160809
79 DNS_PUBLIC const char *dns_vendor(void);
81 DNS_PUBLIC int dns_v_rel(void);
82 DNS_PUBLIC int dns_v_abi(void);
83 DNS_PUBLIC int dns_v_api(void);
89 * Errors and exceptions are always returned through an int. This should
90 * hopefully make integration easier in the majority of circumstances, and
91 * also cut down on useless compiler warnings.
93 * System and library errors are returned together. POSIX guarantees that
94 * all system errors are positive integers. Library errors are always
95 * negative integers in the range DNS_EBASE to DNS_ELAST, with the high bits
96 * set to the three magic ASCII characters "dns".
98 * dns_strerror() returns static English string descriptions of all known
99 * errors, and punts the remainder to strerror(3).
101 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
103 #define DNS_EBASE -(('d' << 24) | ('n' << 16) | ('s' << 8) | 64)
105 #define dns_error_t int /* for documentation only */
108 DNS_ENOBUFS = DNS_EBASE,
117 DNS_ESERVICE, /* EAI_SERVICE */
118 DNS_ENONAME, /* EAI_NONAME */
119 DNS_EFAIL, /* EAI_FAIL */
125 DNS_PUBLIC const char *dns_strerror(dns_error_t);
127 DNS_PUBLIC int *dns_debug_p(void);
129 #define dns_debug (*dns_debug_p()) /* was extern int dns_debug before 20160523 API */
133 * C O M P I L E R A N N O T A T I O N S
135 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
137 #if defined __clang__
138 #define DNS_PRAGMA_PUSH _Pragma("clang diagnostic push")
139 #define DNS_PRAGMA_QUIET _Pragma("clang diagnostic ignored \"-Winitializer-overrides\"")
140 #define DNS_PRAGMA_POP _Pragma("clang diagnostic pop")
142 #elif (__GNUC__ == 4 && __GNUC_MINOR__ >= 6) || __GNUC__ > 4
143 #define DNS_PRAGMA_PUSH _Pragma("GCC diagnostic push")
144 #define DNS_PRAGMA_QUIET _Pragma("GCC diagnostic ignored \"-Woverride-init\"")
145 #define DNS_PRAGMA_POP _Pragma("GCC diagnostic pop")
148 #define DNS_PRAGMA_PUSH
149 #define DNS_PRAGMA_QUIET
150 #define DNS_PRAGMA_POP
154 #define DNS_PRAGMA_EXTENSION __extension__
156 #define DNS_PRAGMA_EXTENSION
161 * E V E N T S I N T E R F A C E S
163 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
166 #define DNS_POLLIN POLLIN
172 #define DNS_POLLOUT POLLOUT
174 #define DNS_POLLOUT 2
179 * See Application Interface below for configuring libevent bitmasks instead
180 * of poll(2) bitmasks.
183 #define DNS_EVWRITE 4
186 #define DNS_POLL2EV(set) \
187 (((set) & DNS_POLLIN)? DNS_EVREAD : 0) | (((set) & DNS_POLLOUT)? DNS_EVWRITE : 0)
189 #define DNS_EV2POLL(set) \
190 (((set) & DNS_EVREAD)? DNS_POLLIN : 0) | (((set) & DNS_EVWRITE)? DNS_POLLOUT : 0)
194 * E N U M E R A T I O N I N T E R F A C E S
196 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
200 #define DNS_S_QUESTION DNS_S_QD
203 #define DNS_S_ANSWER DNS_S_AN
206 #define DNS_S_AUTHORITY DNS_S_NS
209 #define DNS_S_ADDITIONAL DNS_S_AR
212 }; /* enum dns_section */
219 }; /* enum dns_class */
238 }; /* enum dns_type */
263 /* EDNS(0) extended RCODEs */
269 * NOTE: These string functions need a small buffer in case the literal
270 * integer value needs to be printed and returned. UNLESS this buffer is
271 * SPECIFIED, the returned string has ONLY BLOCK SCOPE.
273 #define DNS_STRMAXLEN 47 /* "QUESTION|ANSWER|AUTHORITY|ADDITIONAL" */
275 DNS_PUBLIC const char *dns_strsection(enum dns_section, char *);
277 DNS_PUBLIC enum dns_section dns_isection(const char *);
279 DNS_PUBLIC const char *dns_strclass(enum dns_class, char *);
281 DNS_PUBLIC enum dns_class dns_iclass(const char *);
283 DNS_PUBLIC const char *dns_strtype(enum dns_type, char *);
285 DNS_PUBLIC enum dns_type dns_itype(const char *);
287 DNS_PUBLIC const char *dns_stropcode(enum dns_opcode);
289 DNS_PUBLIC enum dns_opcode dns_iopcode(const char *);
291 DNS_PUBLIC const char *dns_strrcode(enum dns_rcode);
293 DNS_PUBLIC enum dns_rcode dns_ircode(const char *);
297 * A T O M I C I N T E R F A C E S
299 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
301 typedef unsigned long dns_atomic_t;
303 typedef unsigned long dns_refcount_t; /* must be same value type as dns_atomic_t */
307 * C R Y P T O I N T E R F A C E S
309 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
311 typedef unsigned dns_random_f(void);
313 DNS_PUBLIC dns_random_f **dns_random_p(void);
315 #define dns_random (*dns_random_p()) /* was extern unsigned (*dns_random)(void) before 20160523 API */
319 * P A C K E T I N T E R F A C E
321 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
326 #if (defined BYTE_ORDER && BYTE_ORDER == BIG_ENDIAN) || (defined __sun && defined _BIG_ENDIAN)
352 }; /* struct dns_header */
354 #define dns_header(p) (&(p)->header)
357 #ifndef DNS_P_QBUFSIZ
358 #define DNS_P_QBUFSIZ dns_p_calcsize(256 + 4)
361 #ifndef DNS_P_DICTSIZE
362 #define DNS_P_DICTSIZE 16
366 unsigned short dict[DNS_P_DICTSIZE];
370 unsigned short base, end;
375 unsigned short maxudp;
380 struct { struct dns_packet *cqe_next, *cqe_prev; } cqe;
384 int:16; /* tcp padding */
386 DNS_PRAGMA_EXTENSION union {
387 struct dns_header header;
388 unsigned char data[1];
390 }; /* struct dns_packet */
392 #define dns_p_calcsize(n) (offsetof(struct dns_packet, data) + DNS_PP_MAX(12, (n)))
394 #define dns_p_sizeof(P) dns_p_calcsize((P)->end)
396 /** takes size of entire packet structure as allocated */
397 DNS_PUBLIC struct dns_packet *dns_p_init(struct dns_packet *, size_t);
399 /** takes size of maximum desired payload */
400 DNS_PUBLIC struct dns_packet *dns_p_make(size_t, int *);
402 DNS_PUBLIC int dns_p_grow(struct dns_packet **);
404 DNS_PUBLIC struct dns_packet *dns_p_copy(struct dns_packet *, const struct dns_packet *);
406 #define dns_p_opcode(P) (dns_header(P)->opcode)
408 DNS_PUBLIC enum dns_rcode dns_p_rcode(struct dns_packet *);
410 DNS_PUBLIC unsigned dns_p_count(struct dns_packet *, enum dns_section);
412 DNS_PUBLIC int dns_p_push(struct dns_packet *, enum dns_section, const void *, size_t, enum dns_type, enum dns_class, unsigned, const void *);
414 DNS_PUBLIC void dns_p_dictadd(struct dns_packet *, unsigned short);
416 DNS_PUBLIC struct dns_packet *dns_p_merge(struct dns_packet *, enum dns_section, struct dns_packet *, enum dns_section, int *);
418 DNS_PUBLIC void dns_p_dump(struct dns_packet *, FILE *);
420 DNS_PUBLIC int dns_p_study(struct dns_packet *);
424 * D O M A I N N A M E I N T E R F A C E S
426 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
428 #define DNS_D_MAXLABEL 63 /* + 1 '\0' */
429 #define DNS_D_MAXNAME 255 /* + 1 '\0' */
431 #define DNS_D_ANCHOR 1 /* anchor domain w/ root "." */
432 #define DNS_D_CLEAVE 2 /* cleave sub-domain */
433 #define DNS_D_TRIM 4 /* remove superfluous dots */
435 DNS_PUBLIC char *dns_d_init(void *, size_t, const void *, size_t, int);
437 DNS_PUBLIC size_t dns_d_anchor(void *, size_t, const void *, size_t);
439 DNS_PUBLIC size_t dns_d_cleave(void *, size_t, const void *, size_t);
441 DNS_PUBLIC size_t dns_d_comp(void *, size_t, const void *, size_t, struct dns_packet *, int *);
443 DNS_PUBLIC size_t dns_d_expand(void *, size_t, unsigned short, struct dns_packet *, int *);
445 DNS_PUBLIC unsigned short dns_d_skip(unsigned short, struct dns_packet *);
447 DNS_PUBLIC int dns_d_push(struct dns_packet *, const void *, size_t);
449 DNS_PUBLIC size_t dns_d_cname(void *, size_t, const void *, size_t, struct dns_packet *, int *error);
453 * R E S O U R C E R E C O R D I N T E R F A C E S
455 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
458 enum dns_section section;
466 enum dns_class class;
473 }; /* struct dns_rr */
476 DNS_PUBLIC int dns_rr_copy(struct dns_packet *, struct dns_rr *, struct dns_packet *);
478 DNS_PUBLIC int dns_rr_parse(struct dns_rr *, unsigned short, struct dns_packet *);
480 DNS_PUBLIC unsigned short dns_rr_skip(unsigned short, struct dns_packet *);
482 DNS_PUBLIC int dns_rr_cmp(struct dns_rr *, struct dns_packet *, struct dns_rr *, struct dns_packet *);
484 DNS_PUBLIC size_t dns_rr_print(void *, size_t, struct dns_rr *, struct dns_packet *, int *);
488 enum dns_section section;
491 enum dns_class class;
496 int (*sort)(struct dns_rr *, struct dns_rr *, struct dns_rr_i *, struct dns_packet *);
501 unsigned short count;
506 }; /* struct dns_rr_i */
508 DNS_PUBLIC int dns_rr_i_packet(struct dns_rr *, struct dns_rr *, struct dns_rr_i *, struct dns_packet *);
510 DNS_PUBLIC int dns_rr_i_order(struct dns_rr *, struct dns_rr *, struct dns_rr_i *, struct dns_packet *);
512 DNS_PUBLIC int dns_rr_i_shuffle(struct dns_rr *, struct dns_rr *, struct dns_rr_i *, struct dns_packet *);
514 DNS_PUBLIC void dns_rr_i_init(struct dns_rr_i *);
516 #define dns_rr_i_save(i) ((i)->saved = (i)->state)
517 #define dns_rr_i_rewind(i) ((i)->state = (i)->saved)
518 #define dns_rr_i_count(i) ((i)->state.count)
520 DNS_PUBLIC unsigned dns_rr_grep(struct dns_rr *, unsigned, struct dns_rr_i *, struct dns_packet *, int *);
522 #define dns_rr_foreach_(rr, P, ...) \
523 for (struct dns_rr_i DNS_PP_XPASTE(i, __LINE__) = { __VA_ARGS__ }; dns_rr_grep((rr), 1, &DNS_PP_XPASTE(i, __LINE__), (P), NULL); )
525 #define dns_rr_foreach(...) dns_rr_foreach_(__VA_ARGS__)
529 * A R E S O U R C E R E C O R D
534 }; /* struct dns_a */
536 DNS_PUBLIC int dns_a_parse(struct dns_a *, struct dns_rr *, struct dns_packet *);
538 DNS_PUBLIC int dns_a_push(struct dns_packet *, struct dns_a *);
540 DNS_PUBLIC int dns_a_cmp(const struct dns_a *, const struct dns_a *);
542 DNS_PUBLIC size_t dns_a_print(void *, size_t, struct dns_a *);
544 DNS_PUBLIC size_t dns_a_arpa(void *, size_t, const struct dns_a *);
548 * AAAA R E S O U R C E R E C O R D
552 struct in6_addr addr;
553 }; /* struct dns_aaaa */
555 DNS_PUBLIC int dns_aaaa_parse(struct dns_aaaa *, struct dns_rr *, struct dns_packet *);
557 DNS_PUBLIC int dns_aaaa_push(struct dns_packet *, struct dns_aaaa *);
559 DNS_PUBLIC int dns_aaaa_cmp(const struct dns_aaaa *, const struct dns_aaaa *);
561 DNS_PUBLIC size_t dns_aaaa_print(void *, size_t, struct dns_aaaa *);
563 DNS_PUBLIC size_t dns_aaaa_arpa(void *, size_t, const struct dns_aaaa *);
567 * MX R E S O U R C E R E C O R D
571 unsigned short preference;
572 char host[DNS_D_MAXNAME + 1];
573 }; /* struct dns_mx */
575 DNS_PUBLIC int dns_mx_parse(struct dns_mx *, struct dns_rr *, struct dns_packet *);
577 DNS_PUBLIC int dns_mx_push(struct dns_packet *, struct dns_mx *);
579 DNS_PUBLIC int dns_mx_cmp(const struct dns_mx *, const struct dns_mx *);
581 DNS_PUBLIC size_t dns_mx_print(void *, size_t, struct dns_mx *);
583 DNS_PUBLIC size_t dns_mx_cname(void *, size_t, struct dns_mx *);
587 * NS R E S O U R C E R E C O R D
591 char host[DNS_D_MAXNAME + 1];
592 }; /* struct dns_ns */
594 DNS_PUBLIC int dns_ns_parse(struct dns_ns *, struct dns_rr *, struct dns_packet *);
596 DNS_PUBLIC int dns_ns_push(struct dns_packet *, struct dns_ns *);
598 DNS_PUBLIC int dns_ns_cmp(const struct dns_ns *, const struct dns_ns *);
600 DNS_PUBLIC size_t dns_ns_print(void *, size_t, struct dns_ns *);
602 DNS_PUBLIC size_t dns_ns_cname(void *, size_t, struct dns_ns *);
606 * CNAME R E S O U R C E R E C O R D
610 char host[DNS_D_MAXNAME + 1];
611 }; /* struct dns_cname */
613 DNS_PUBLIC int dns_cname_parse(struct dns_cname *, struct dns_rr *, struct dns_packet *);
615 DNS_PUBLIC int dns_cname_push(struct dns_packet *, struct dns_cname *);
617 DNS_PUBLIC int dns_cname_cmp(const struct dns_cname *, const struct dns_cname *);
619 DNS_PUBLIC size_t dns_cname_print(void *, size_t, struct dns_cname *);
621 DNS_PUBLIC size_t dns_cname_cname(void *, size_t, struct dns_cname *);
625 * SOA R E S O U R C E R E C O R D
629 char mname[DNS_D_MAXNAME + 1];
630 char rname[DNS_D_MAXNAME + 1];
631 unsigned serial, refresh, retry, expire, minimum;
632 }; /* struct dns_soa */
634 DNS_PUBLIC int dns_soa_parse(struct dns_soa *, struct dns_rr *, struct dns_packet *);
636 DNS_PUBLIC int dns_soa_push(struct dns_packet *, struct dns_soa *);
638 DNS_PUBLIC int dns_soa_cmp(const struct dns_soa *, const struct dns_soa *);
640 DNS_PUBLIC size_t dns_soa_print(void *, size_t, struct dns_soa *);
644 * PTR R E S O U R C E R E C O R D
648 char host[DNS_D_MAXNAME + 1];
649 }; /* struct dns_ptr */
651 DNS_PUBLIC int dns_ptr_parse(struct dns_ptr *, struct dns_rr *, struct dns_packet *);
653 DNS_PUBLIC int dns_ptr_push(struct dns_packet *, struct dns_ptr *);
655 DNS_PUBLIC int dns_ptr_cmp(const struct dns_ptr *, const struct dns_ptr *);
657 DNS_PUBLIC size_t dns_ptr_print(void *, size_t, struct dns_ptr *);
659 DNS_PUBLIC size_t dns_ptr_cname(void *, size_t, struct dns_ptr *);
661 DNS_PUBLIC size_t dns_ptr_qname(void *, size_t, int, void *);
665 * SRV R E S O U R C E R E C O R D
669 unsigned short priority;
670 unsigned short weight;
672 char target[DNS_D_MAXNAME + 1];
673 }; /* struct dns_srv */
675 DNS_PUBLIC int dns_srv_parse(struct dns_srv *, struct dns_rr *, struct dns_packet *);
677 DNS_PUBLIC int dns_srv_push(struct dns_packet *, struct dns_srv *);
679 DNS_PUBLIC int dns_srv_cmp(const struct dns_srv *, const struct dns_srv *);
681 DNS_PUBLIC size_t dns_srv_print(void *, size_t, struct dns_srv *);
683 DNS_PUBLIC size_t dns_srv_cname(void *, size_t, struct dns_srv *);
687 * OPT R E S O U R C E R E C O R D
690 #ifndef DNS_OPT_MINDATA
691 #define DNS_OPT_MINDATA 256
694 #define DNS_OPT_DNSSEC 0x8000
697 enum dns_rcode rcode;
698 unsigned char version;
699 unsigned short flags;
702 unsigned short maxsize; /* deprecated as confusing */
703 unsigned short maxudp; /* maximum UDP payload size */
707 unsigned char data[DNS_OPT_MINDATA];
708 }; /* struct dns_opt */
710 #define DNS_OPT_INIT(opt) { .size = sizeof (*opt) - offsetof(struct dns_opt, data) }
712 DNS_PUBLIC struct dns_opt *dns_opt_init(struct dns_opt *, size_t);
714 DNS_PUBLIC int dns_opt_parse(struct dns_opt *, struct dns_rr *, struct dns_packet *);
716 DNS_PUBLIC int dns_opt_push(struct dns_packet *, struct dns_opt *);
718 DNS_PUBLIC int dns_opt_cmp(const struct dns_opt *, const struct dns_opt *);
720 DNS_PUBLIC size_t dns_opt_print(void *, size_t, struct dns_opt *);
722 DNS_PUBLIC unsigned int dns_opt_ttl(const struct dns_opt *);
724 DNS_PUBLIC unsigned short dns_opt_class(const struct dns_opt *);
726 DNS_PUBLIC dns_error_t dns_opt_data_push(struct dns_opt *, unsigned char, unsigned short, const void *);
730 * SSHFP R E S O U R C E R E C O R D
739 enum dns_sshfp_digest {
744 unsigned char sha1[20];
746 }; /* struct dns_sshfp */
748 DNS_PUBLIC int dns_sshfp_parse(struct dns_sshfp *, struct dns_rr *, struct dns_packet *);
750 DNS_PUBLIC int dns_sshfp_push(struct dns_packet *, struct dns_sshfp *);
752 DNS_PUBLIC int dns_sshfp_cmp(const struct dns_sshfp *, const struct dns_sshfp *);
754 DNS_PUBLIC size_t dns_sshfp_print(void *, size_t, struct dns_sshfp *);
758 * TXT R E S O U R C E R E C O R D
761 #ifndef DNS_TXT_MINDATA
762 #define DNS_TXT_MINDATA 1024
767 unsigned char data[DNS_TXT_MINDATA];
768 }; /* struct dns_txt */
770 DNS_PUBLIC struct dns_txt *dns_txt_init(struct dns_txt *, size_t);
772 DNS_PUBLIC int dns_txt_parse(struct dns_txt *, struct dns_rr *, struct dns_packet *);
774 DNS_PUBLIC int dns_txt_push(struct dns_packet *, struct dns_txt *);
776 DNS_PUBLIC int dns_txt_cmp(const struct dns_txt *, const struct dns_txt *);
778 DNS_PUBLIC size_t dns_txt_print(void *, size_t, struct dns_txt *);
782 * ANY R E S O U R C E R E C O R D
787 struct dns_aaaa aaaa;
790 struct dns_cname cname;
795 struct dns_sshfp sshfp;
796 struct dns_txt txt, spf, rdata;
797 }; /* union dns_any */
799 #define DNS_ANY_INIT(any) { .rdata = { .size = sizeof *(any) - offsetof(struct dns_txt, data) } }
801 DNS_PUBLIC union dns_any *dns_any_init(union dns_any *, size_t);
803 DNS_PUBLIC int dns_any_parse(union dns_any *, struct dns_rr *, struct dns_packet *);
805 DNS_PUBLIC int dns_any_push(struct dns_packet *, union dns_any *, enum dns_type);
807 DNS_PUBLIC int dns_any_cmp(const union dns_any *, enum dns_type, const union dns_any *, enum dns_type);
809 DNS_PUBLIC size_t dns_any_print(void *, size_t, union dns_any *, enum dns_type);
811 DNS_PUBLIC size_t dns_any_cname(void *, size_t, union dns_any *, enum dns_type);
815 * H O S T S I N T E R F A C E
817 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
821 DNS_PUBLIC struct dns_hosts *dns_hosts_open(int *);
823 DNS_PUBLIC void dns_hosts_close(struct dns_hosts *);
825 DNS_PUBLIC dns_refcount_t dns_hosts_acquire(struct dns_hosts *);
827 DNS_PUBLIC dns_refcount_t dns_hosts_release(struct dns_hosts *);
829 DNS_PUBLIC struct dns_hosts *dns_hosts_mortal(struct dns_hosts *);
831 DNS_PUBLIC struct dns_hosts *dns_hosts_local(int *);
833 DNS_PUBLIC int dns_hosts_loadfile(struct dns_hosts *, FILE *);
835 DNS_PUBLIC int dns_hosts_loadpath(struct dns_hosts *, const char *);
837 DNS_PUBLIC int dns_hosts_dump(struct dns_hosts *, FILE *);
839 DNS_PUBLIC int dns_hosts_insert(struct dns_hosts *, int, const void *, const void *, _Bool);
841 DNS_PUBLIC struct dns_packet *dns_hosts_query(struct dns_hosts *, struct dns_packet *, int *);
845 * R E S O L V . C O N F I N T E R F A C E
847 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
849 struct dns_resolv_conf {
850 struct sockaddr_storage nameserver[3];
852 char search[4][DNS_D_MAXNAME + 1];
854 /* (f)ile, (b)ind, (c)ache */
855 char lookup[4 * (1 + (4 * 2))];
857 /* getaddrinfo family by preference order ("inet4", "inet6") */
876 DNS_RESCONF_TCP_ENABLE,
877 DNS_RESCONF_TCP_ONLY,
878 DNS_RESCONF_TCP_SOCKS,
879 DNS_RESCONF_TCP_DISABLE,
883 struct sockaddr_storage iface;
885 struct { /* PRIVATE */
886 dns_atomic_t refcount;
888 }; /* struct dns_resolv_conf */
890 DNS_PUBLIC struct dns_resolv_conf *dns_resconf_open(int *);
892 DNS_PUBLIC void dns_resconf_close(struct dns_resolv_conf *);
894 DNS_PUBLIC dns_refcount_t dns_resconf_acquire(struct dns_resolv_conf *);
896 DNS_PUBLIC dns_refcount_t dns_resconf_release(struct dns_resolv_conf *);
898 DNS_PUBLIC struct dns_resolv_conf *dns_resconf_mortal(struct dns_resolv_conf *);
900 DNS_PUBLIC struct dns_resolv_conf *dns_resconf_local(int *);
902 DNS_PUBLIC struct dns_resolv_conf *dns_resconf_root(int *);
904 DNS_PUBLIC int dns_resconf_pton(struct sockaddr_storage *, const char *);
906 DNS_PUBLIC int dns_resconf_loadfile(struct dns_resolv_conf *, FILE *);
908 DNS_PUBLIC int dns_resconf_loadpath(struct dns_resolv_conf *, const char *);
910 DNS_PUBLIC int dns_nssconf_loadfile(struct dns_resolv_conf *, FILE *);
912 DNS_PUBLIC int dns_nssconf_loadpath(struct dns_resolv_conf *, const char *);
914 DNS_PUBLIC int dns_resconf_dump(struct dns_resolv_conf *, FILE *);
916 DNS_PUBLIC int dns_nssconf_dump(struct dns_resolv_conf *, FILE *);
918 DNS_PUBLIC int dns_resconf_setiface(struct dns_resolv_conf *, const char *, unsigned short);
920 typedef unsigned long dns_resconf_i_t;
922 DNS_PUBLIC size_t dns_resconf_search(void *, size_t, const void *, size_t, struct dns_resolv_conf *, dns_resconf_i_t *);
926 * H I N T S E R V E R I N T E R F A C E
928 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
932 DNS_PUBLIC struct dns_hints *dns_hints_open(struct dns_resolv_conf *, int *);
934 DNS_PUBLIC void dns_hints_close(struct dns_hints *);
936 DNS_PUBLIC dns_refcount_t dns_hints_acquire(struct dns_hints *);
938 DNS_PUBLIC dns_refcount_t dns_hints_release(struct dns_hints *);
940 DNS_PUBLIC struct dns_hints *dns_hints_mortal(struct dns_hints *);
942 DNS_PUBLIC int dns_hints_insert(struct dns_hints *, const char *, const struct sockaddr *, unsigned);
944 DNS_PUBLIC unsigned dns_hints_insert_resconf(struct dns_hints *, const char *, const struct dns_resolv_conf *, int *);
946 DNS_PUBLIC struct dns_hints *dns_hints_local(struct dns_resolv_conf *, int *);
948 DNS_PUBLIC struct dns_hints *dns_hints_root(struct dns_resolv_conf *, int *);
950 DNS_PUBLIC struct dns_packet *dns_hints_query(struct dns_hints *, struct dns_packet *, int *);
952 DNS_PUBLIC int dns_hints_dump(struct dns_hints *, FILE *);
962 }; /* struct dns_hints_i */
965 DNS_PUBLIC unsigned dns_hints_grep(struct sockaddr **, socklen_t *, unsigned, struct dns_hints_i *, struct dns_hints *);
969 * C A C H E I N T E R F A C E
971 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
976 dns_refcount_t (*acquire)(struct dns_cache *);
977 dns_refcount_t (*release)(struct dns_cache *);
979 struct dns_packet *(*query)(struct dns_packet *, struct dns_cache *, int *);
981 int (*submit)(struct dns_packet *, struct dns_cache *);
982 int (*check)(struct dns_cache *);
983 struct dns_packet *(*fetch)(struct dns_cache *, int *);
985 int (*pollfd)(struct dns_cache *);
986 short (*events)(struct dns_cache *);
987 void (*clear)(struct dns_cache *);
994 struct { /* PRIVATE */
995 dns_atomic_t refcount;
997 }; /* struct dns_cache */
1000 DNS_PUBLIC struct dns_cache *dns_cache_init(struct dns_cache *);
1002 DNS_PUBLIC void dns_cache_close(struct dns_cache *);
1006 * A P P L I C A T I O N I N T E R F A C E
1008 * Options to change the behavior of the API. Applies across all the
1009 * different components.
1011 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1013 #define DNS_OPTS_INITIALIZER_ { 0, 0 }, 0, 0
1014 #define DNS_OPTS_INITIALIZER { DNS_OPTS_INITIALIZER_ }
1016 struct dns_options {
1018 * If the callback closes *fd, it must set it to -1. Otherwise, the
1019 * descriptor is queued and lazily closed at object destruction or
1020 * by an explicit call to _clear(). This allows safe use of
1021 * kqueue(2), epoll(2), et al -style persistent events.
1025 int (*cb)(int *fd, void *arg);
1028 /* bitmask for _events() routines */
1034 /* Use this SOCKS server. */
1035 const struct sockaddr_storage *socks_host;
1037 /* Credentials for the SOCKS server (optional). */
1038 const char *socks_user;
1039 const char *socks_password;
1040 }; /* struct dns_options */
1044 * S T A T S I N T E R F A C E S
1046 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1053 size_t count, bytes;
1056 }; /* struct dns_stat */
1060 * S O C K E T I N T E R F A C E
1062 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1066 DNS_PUBLIC struct dns_socket *dns_so_open(const struct sockaddr *, int, const struct dns_options *, int *error);
1068 DNS_PUBLIC void dns_so_close(struct dns_socket *);
1070 DNS_PUBLIC void dns_so_reset(struct dns_socket *);
1072 DNS_PUBLIC unsigned short dns_so_mkqid(struct dns_socket *so);
1074 DNS_PUBLIC struct dns_packet *dns_so_query(struct dns_socket *, struct dns_packet *, struct sockaddr *, int *);
1076 DNS_PUBLIC int dns_so_submit(struct dns_socket *, struct dns_packet *, struct sockaddr *);
1078 DNS_PUBLIC int dns_so_check(struct dns_socket *);
1080 DNS_PUBLIC struct dns_packet *dns_so_fetch(struct dns_socket *, int *);
1082 DNS_PUBLIC time_t dns_so_elapsed(struct dns_socket *);
1084 DNS_PUBLIC void dns_so_clear(struct dns_socket *);
1086 DNS_PUBLIC int dns_so_events(struct dns_socket *);
1088 DNS_PUBLIC int dns_so_pollfd(struct dns_socket *);
1090 DNS_PUBLIC int dns_so_poll(struct dns_socket *, int);
1092 DNS_PUBLIC const struct dns_stat *dns_so_stat(struct dns_socket *);
1094 DNS_PUBLIC struct dns_trace *dns_so_trace(struct dns_socket *);
1096 DNS_PUBLIC void dns_so_settrace(struct dns_socket *, struct dns_trace *);
1100 * R E S O L V E R I N T E R F A C E
1102 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1104 struct dns_resolver;
1106 DNS_PUBLIC struct dns_resolver *dns_res_open(struct dns_resolv_conf *, struct dns_hosts *hosts, struct dns_hints *, struct dns_cache *, const struct dns_options *, int *);
1108 DNS_PUBLIC struct dns_resolver *dns_res_stub(const struct dns_options *, int *);
1110 DNS_PUBLIC void dns_res_reset(struct dns_resolver *);
1112 DNS_PUBLIC void dns_res_close(struct dns_resolver *);
1114 DNS_PUBLIC dns_refcount_t dns_res_acquire(struct dns_resolver *);
1116 DNS_PUBLIC dns_refcount_t dns_res_release(struct dns_resolver *);
1118 DNS_PUBLIC struct dns_resolver *dns_res_mortal(struct dns_resolver *);
1120 DNS_PUBLIC int dns_res_submit(struct dns_resolver *, const char *, enum dns_type, enum dns_class);
1122 DNS_PUBLIC int dns_res_submit2(struct dns_resolver *, const char *, size_t, enum dns_type, enum dns_class);
1124 DNS_PUBLIC int dns_res_check(struct dns_resolver *);
1126 DNS_PUBLIC struct dns_packet *dns_res_fetch(struct dns_resolver *, int *);
1128 DNS_PUBLIC time_t dns_res_elapsed(struct dns_resolver *);
1130 DNS_PUBLIC void dns_res_clear(struct dns_resolver *);
1132 DNS_PUBLIC int dns_res_events(struct dns_resolver *);
1134 DNS_PUBLIC int dns_res_pollfd(struct dns_resolver *);
1136 DNS_PUBLIC time_t dns_res_timeout(struct dns_resolver *);
1138 DNS_PUBLIC int dns_res_poll(struct dns_resolver *, int);
1140 DNS_PUBLIC struct dns_packet *dns_res_query(struct dns_resolver *, const char *, enum dns_type, enum dns_class, int, int *);
1142 DNS_PUBLIC const struct dns_stat *dns_res_stat(struct dns_resolver *);
1144 DNS_PUBLIC void dns_res_sethints(struct dns_resolver *, struct dns_hints *);
1146 DNS_PUBLIC struct dns_trace *dns_res_trace(struct dns_resolver *);
1148 DNS_PUBLIC void dns_res_settrace(struct dns_resolver *, struct dns_trace *);
1152 * A D D R I N F O I N T E R F A C E
1154 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1156 struct dns_addrinfo;
1158 DNS_PUBLIC struct dns_addrinfo *dns_ai_open(const char *, const char *, enum dns_type, const struct addrinfo *, struct dns_resolver *, int *);
1160 DNS_PUBLIC void dns_ai_close(struct dns_addrinfo *);
1162 DNS_PUBLIC int dns_ai_nextent(struct addrinfo **, struct dns_addrinfo *);
1164 DNS_PUBLIC size_t dns_ai_print(void *, size_t, struct addrinfo *, struct dns_addrinfo *);
1166 DNS_PUBLIC time_t dns_ai_elapsed(struct dns_addrinfo *);
1168 DNS_PUBLIC void dns_ai_clear(struct dns_addrinfo *);
1170 DNS_PUBLIC int dns_ai_events(struct dns_addrinfo *);
1172 DNS_PUBLIC int dns_ai_pollfd(struct dns_addrinfo *);
1174 DNS_PUBLIC time_t dns_ai_timeout(struct dns_addrinfo *);
1176 DNS_PUBLIC int dns_ai_poll(struct dns_addrinfo *, int);
1178 DNS_PUBLIC const struct dns_stat *dns_ai_stat(struct dns_addrinfo *);
1180 DNS_PUBLIC struct dns_trace *dns_ai_trace(struct dns_addrinfo *);
1182 DNS_PUBLIC void dns_ai_settrace(struct dns_addrinfo *, struct dns_trace *);
1186 * Q U E R Y T R A C I N G I N T E R F A C E
1188 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1190 #define DNS_TRACE_ID_C(n) UINT64_C(n)
1191 typedef uint64_t dns_trace_id_t;
1193 #define DNS_TRACE_ABI 0x20160803
1195 struct dns_trace_event {
1197 DNS_TE_RES_SUBMIT = 1,
1198 DNS_TE_RES_FETCH = 99,
1200 DNS_TE_SO_SUBMIT = 100,
1202 DNS_TE_SO_FETCH = 199,
1204 DNS_TE_SYS_CONNECT = 200,
1216 char qname[DNS_D_MAXNAME + 1];
1217 enum dns_type qtype;
1218 enum dns_class qclass;
1227 struct sockaddr_storage haddr;
1228 char hname[DNS_D_MAXNAME + 1];
1241 struct sockaddr_storage src, dst;
1244 } sys_connect, sys_send, sys_recv;
1247 unsigned char data[];
1250 static inline size_t dns_te_datasize(const struct dns_trace_event *te) {
1251 size_t n = offsetof(struct dns_trace_event, data);
1252 return (n <= te->size)? te->size - n : 0;
1257 DNS_PUBLIC int dns_trace_abi(void);
1259 DNS_PUBLIC struct dns_trace *dns_trace_open(FILE *, dns_error_t *);
1261 DNS_PUBLIC void dns_trace_close(struct dns_trace *);
1263 DNS_PUBLIC dns_refcount_t dns_trace_acquire(struct dns_trace *);
1265 DNS_PUBLIC dns_refcount_t dns_trace_release(struct dns_trace *);
1267 DNS_PUBLIC dns_trace_id_t dns_trace_id(struct dns_trace *);
1269 DNS_PUBLIC dns_trace_id_t dns_trace_setid(struct dns_trace *, dns_trace_id_t);
1271 DNS_PUBLIC struct dns_trace_event *dns_trace_get(struct dns_trace *, struct dns_trace_event **, dns_error_t *);
1273 DNS_PUBLIC struct dns_trace_event *dns_trace_tag(struct dns_trace *, struct dns_trace_event *);
1275 DNS_PUBLIC dns_error_t dns_trace_put(struct dns_trace *, const struct dns_trace_event *, const void *, size_t);
1277 DNS_PUBLIC dns_error_t dns_trace_dump(struct dns_trace *, FILE *);
1279 DNS_PUBLIC struct dns_trace_event *dns_trace_fget(struct dns_trace_event **, FILE *, dns_error_t *);
1281 DNS_PUBLIC dns_error_t dns_trace_fput(const struct dns_trace_event *, const void *, size_t, FILE *);
1285 * U T I L I T Y I N T E R F A C E S
1287 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1289 DNS_PUBLIC size_t dns_strlcpy(char *, const char *, size_t);
1291 DNS_PUBLIC size_t dns_strlcat(char *, const char *, size_t);
1295 * M A C R O M A G I C S
1297 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1299 #define DNS_PP_MIN(a, b) (((a) < (b))? (a) : (b))
1300 #define DNS_PP_MAX(a, b) (((a) > (b))? (a) : (b))
1301 #define DNS_PP_NARG_(a, b, c, d, e, f, g, h, i, j, k, N,...) N
1302 #define DNS_PP_NARG(...) DNS_PP_NARG_(__VA_ARGS__, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
1303 #define DNS_PP_CALL(F, ...) F(__VA_ARGS__)
1304 #define DNS_PP_PASTE(x, y) x##y
1305 #define DNS_PP_XPASTE(x, y) DNS_PP_PASTE(x, y)
1306 #define DNS_PP_STRINGIFY_(s) #s
1307 #define DNS_PP_STRINGIFY(s) DNS_PP_STRINGIFY_(s)
1317 #define DNS_PP_D10 9
1318 #define DNS_PP_D11 10
1319 #define DNS_PP_DEC(N) DNS_PP_XPASTE(DNS_PP_D, N)