* Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
+/* TCP and UDP server are using a lot of same string constants
+ * We reuse them by keeping both in one source file */
+
+#include "busybox.h"
+
+static unsigned verbose;
+
+static void sig_term_handler(int sig)
+{
+ if (verbose)
+ printf("%s: info: sigterm received, exit\n", applet_name);
+ exit(0);
+}
+
+/* Little bloated, but tries to give accurate info how child exited.
+ * Makes easier to spot segfaulting children etc... */
+static void print_waitstat(unsigned pid, int wstat)
+{
+ unsigned e = 0;
+ const char *cause = "?exit";
+
+ if (WIFEXITED(wstat)) {
+ cause++;
+ e = WEXITSTATUS(wstat);
+ } else if (WIFSIGNALED(wstat)) {
+ cause = "signal";
+ e = WTERMSIG(wstat);
+ }
+ printf("%s: info: end %d %s %d\n", applet_name, pid, cause, e);
+}
+
+
+#if ENABLE_UDPSVD
+/* Based on ipsvd ipsvd-0.12.1. This udpsvd accepts all options
+ * which are supported by one from ipsvd-0.12.1, but not all are
+ * functional. See help text at the end of this file for details.
+ *
+ * Output of verbose mode matches original (modulo bugs and
+ * unimplemented stuff). Unnatural splitting of IP and PORT
+ * is retained (personally I prefer one-value "IP:PORT" notation -
+ * it is a natural string representation of struct sockaddr_XX).
+ */
+
+#include "udp_io.c"
+
+int udpsvd_main(int argc, char **argv);
+int udpsvd_main(int argc, char **argv)
+{
+ const char *instructs;
+ char *str_t, *user;
+ unsigned opt;
+
+ char *remote_hostname = (char*)""; /* used if no -h */
+ char *local_hostname = NULL;
+ char *remote_ip;
+ char *local_ip;// = local_ip; /* gcc */
+ uint16_t local_port, remote_port;
+ len_and_sockaddr remote;
+ len_and_sockaddr *localp;
+ int wstat;
+ unsigned pid;
+ struct bb_uidgid_t ugid;
+
+ enum {
+ OPT_v = (1 << 0),
+ OPT_u = (1 << 1),
+ OPT_l = (1 << 2),
+ OPT_h = (1 << 3),
+ OPT_p = (1 << 4),
+ OPT_i = (1 << 5),
+ OPT_x = (1 << 6),
+ OPT_t = (1 << 7),
+ };
+
+ opt_complementary = "-3:ph:vv";
+ opt = getopt32(argc, argv, "vu:l:hpi:x:t:",
+ &user, &local_hostname, &instructs, &instructs, &str_t, &verbose);
+ if (opt & OPT_u) {
+ if (!get_uidgid(&ugid, user, 1))
+ bb_error_msg_and_die("unknown user/group: %s", user);
+ }
+ argv += optind;
+ if (!argv[0][0] || LONE_CHAR(argv[0], '0'))
+ argv[0] = (char*)"0.0.0.0";
+
+ /* stdout is used for logging, don't buffer */
+ setlinebuf(stdout);
+ bb_sanitize_stdio(); /* fd# 1,2 must be opened */
+
+ signal(SIGTERM, sig_term_handler);
+ signal(SIGPIPE, SIG_IGN);
+
+ local_port = bb_lookup_port(argv[1], "udp", 0);
+ localp = xhost2sockaddr(argv[0], local_port);
+ /* fd #0 is the open UDP socket */
+ xmove_fd(xsocket(localp->sa.sa_family, SOCK_DGRAM, 0), 0);
+ setsockopt_reuseaddr(0); /* crucial */
+ xbind(0, &localp->sa, localp->len);
+ socket_want_pktinfo(0); /* needed for recv_from_to to work */
+
+ if (opt & OPT_u) { /* drop permissions */
+ xsetgid(ugid.gid);
+ xsetuid(ugid.uid);
+ }
+
+ if (verbose) {
+ /* we do it only for ":port" cosmetics... oh well */
+ char *addr = xmalloc_sockaddr2dotted(&localp->sa, localp->len);
+
+ printf("%s: info: listening on %s", applet_name, addr);
+ free(addr);
+ if (option_mask32 & OPT_u)
+ printf(", uid %u, gid %u",
+ (unsigned)ugid.uid, (unsigned)ugid.gid);
+ puts(", starting");
+ }
+
+ again:
+ /* if (recvfrom(0, NULL, 0, MSG_PEEK, &remote.sa, &localp->len) < 0) { */
+ if (recv_from_to(0, NULL, 0, MSG_PEEK, &remote.sa, &localp->sa, localp->len) < 0) {
+ bb_perror_msg("recvfrom");
+ goto again;
+ }
+
+ while ((pid = fork()) < 0) {
+ bb_perror_msg("fork failed, sleeping");
+ sleep(5);
+ }
+ if (pid > 0) { /* parent */
+ while (wait_pid(&wstat, pid) < 0)
+ bb_perror_msg("error waiting for child");
+ if (verbose)
+ print_waitstat(pid, wstat);
+ goto again;
+ }
+
+ /* Child */
+
+ if (verbose) {
+ remote_ip = xmalloc_sockaddr2dotted_noport(&remote.sa, localp->len);
+ local_ip = xmalloc_sockaddr2dotted_noport(&localp->sa, localp->len);
+
+ pid = getpid();
+ printf("%s: info: pid %u from %s\n", applet_name, pid, remote_ip);
+
+ if (!local_hostname) {
+ local_hostname = xmalloc_sockaddr2host_noport(&localp->sa, localp->len);
+ if (!local_hostname)
+ bb_error_msg_and_die("cannot look up local hostname for %s", local_ip);
+ }
+ if (opt & OPT_h) {
+ remote_hostname = xmalloc_sockaddr2host(&remote.sa, localp->len);
+ if (!remote_hostname) {
+ bb_error_msg("warning: cannot look up hostname for %s", remote_ip);
+ remote_hostname = (char*)"";
+ }
+ }
+
+ remote_port = get_nport(&remote.sa);
+ remote_port = ntohs(remote_port);
+ printf("%s: info: %u %s:%s :%s:%s:%u\n",
+ applet_name, pid, local_hostname, local_ip,
+ remote_hostname, remote_ip, remote_port);
+ }
+
+ /* Doesn't work:
+ * we cannot replace fd #0 - we will lose pending packet
+ * which is already buffered for us! And we cannot use fd #1
+ * instead - it will "intercept" all following packets, but child
+ * do not expect data coming *from fd #1*! */
+#if 0
+ /* Make it so that local addr is fixed to localp->sa
+ * and we don't accidentally accept packets to other local IPs. */
+ /* NB: we possibly bind to the _very_ same_ address & port as the one
+ * already bound in parent! This seems to work in Linux.
+ * (otherwise we can move socket to fd #0 only if bind succeeds) */
+ close(0);
+ set_nport(localp, htons(local_port));
+ xmove_fd(xsocket(localp->sa.sa_family, SOCK_DGRAM, 0), 0);
+ setsockopt_reuseaddr(0); /* crucial */
+ xbind(0, &localp->sa, localp->len);
+#endif
+
+ /* Make plain write to fd #1 work for the child by supplying default
+ * destination address. This also restricts incoming packets
+ * to ones coming from this remote IP. */
+ xconnect(0, &remote.sa, localp->len);
+ dup2(0 ,1);
+
+ signal(SIGTERM, SIG_DFL);
+ signal(SIGPIPE, SIG_DFL);
+
+ argv += 2;
+ BB_EXECVP(argv[0], argv);
+ bb_perror_msg_and_die("exec '%s'", argv[0]);
+}
+
+
+/*
+udpsvd [-hpvv] [-u user] [-l name] [-i dir|-x cdb] [-t sec] host port prog
+
+udpsvd creates an UDP/IP socket, binds it to the address host:port,
+and listens on the socket for incoming datagrams.
+
+If a datagram is available on the socket, udpsvd conditionally starts
+a program, with standard input reading from the socket, and standard
+output redirected to standard error, to handle this, and possibly
+more datagrams. udpsvd does not start the program if another program
+that it has started before still is running. If the program exits,
+udpsvd again listens to the socket until a new datagram is available.
+If there are still datagrams available on the socket, the program
+is restarted immediately.
+
+udpsvd optionally checks for special intructions depending on
+the IP address or hostname of the client sending the datagram which
+not yet was handled by a running program, see ipsvd-instruct(5)
+for details.
+
+Attention:
+UDP is a connectionless protocol. Most programs that handle user datagrams,
+such as talkd(8), keep running after receiving a datagram, and process
+subsequent datagrams sent to the socket until a timeout is reached.
+udpsvd only checks special instructions for a datagram that causes a startup
+of the program; not if a program handling datagrams already is running.
+It doesn't make much sense to restrict access through special instructions
+when using such a program.
+
+On the other hand, it makes perfectly sense with programs like tftpd(8),
+that fork to establish a separate connection to the client when receiving
+the datagram. In general it's adequate to set up special instructions for
+programs that support being run by tcpwrapper.
+Options
+
+host
+ host either is a hostname, or a dotted-decimal IP address, or 0.
+ If host is 0, udpsvd accepts datagrams to any local IP address.
+port
+ udpsvd accepts datagrams to host:port. port may be a name from
+ /etc/services or a number.
+prog
+ prog consists of one or more arguments. udpsvd normally runs prog
+ to handle a datagram, and possibly more, that is sent to the socket,
+ if there is no program that was started before by udpsvd still running
+ and handling datagrams.
+-i dir
+ read instructions for handling new connections from the instructions
+ directory dir. See ipsvd-instruct(5) for details.
+-x cdb
+ read instructions for handling new connections from the constant
+ database cdb. The constant database normally is created from
+ an instructions directory by running ipsvd-cdb(8).
+-t sec
+ timeout. This option only takes effect if the -i option is given.
+ While checking the instructions directory, check the time of last
+ access of the file that matches the clients address or hostname if any,
+ discard and remove the file if it wasn't accessed within the last
+ sec seconds; udpsvd does not discard or remove a file if the user's
+ write permission is not set, for those files the timeout is disabled.
+ Default is 0, which means that the timeout is disabled.
+-l name
+ local hostname. Do not look up the local hostname in DNS, but use name
+ as hostname. By default udpsvd looks up the local hostname once at startup.
+-u user[:group]
+ drop permissions. Switch user ID to user's UID, and group ID to user's
+ primary GID after creating and binding to the socket. If user
+ is followed by a colon and a group name, the group ID is switched
+ to the GID of group instead. All supplementary groups are removed.
+-h
+ Look up the client's hostname in DNS.
+-p
+ paranoid. After looking up the client's hostname in DNS, look up
+ the IP addresses in DNS for that hostname, and forget the hostname
+ if none of the addresses match the client's IP address. You should
+ set this option if you use hostname based instructions. The -p option
+ implies the -h option.
+-v
+ verbose. Print verbose messages to standard output.
+-vv
+ more verbose. Print more verbose messages to standard output.
+*/
+#endif
+
+
+#if ENABLE_TCPSVD
/* Based on ipsvd ipsvd-0.12.1. This tcpsvd accepts all options
* which are supported by one from ipsvd-0.12.1, but not all are
* functional. See help text at the end of this file for details.
*
* Code inside "#ifdef SSLSVD" is for sslsvd and is currently unused.
- * Code inside #if 0" is parts of original tcpsvd which are not implemented
- * for busyboxed version.
*
* Output of verbose mode matches original (modulo bugs and
* unimplemented stuff). Unnatural splitting of IP and PORT
#include <limits.h>
#include <linux/netfilter_ipv4.h> /* wants <limits.h> */
-#include "busybox.h"
#include "ipsvd_perhost.h"
#ifdef SSLSVD
#include "ssl_io.h"
#endif
-
static unsigned max_per_host; /* originally in ipsvd_check.c */
static unsigned cur_per_host;
-static unsigned verbose;
static unsigned cnum;
static unsigned cmax = 30;
printf("%s: info: status %u/%u\n", applet_name, cnum, cmax);
}
-static void sig_term_handler(int sig)
-{
- if (verbose)
- printf("%s: info: sigterm received, exit\n", applet_name);
- exit(0);
-}
-
static void sig_child_handler(int sig)
{
int wstat;
ipsvd_perhost_remove(pid);
if (cnum)
cnum--;
- if (verbose) {
- /* Little bloated, but tries to give accurate info
- * how child exited. Makes easier to spot segfaulting
- * children etc... */
- unsigned e = 0;
- const char *cause = "?exit";
- if (WIFEXITED(wstat)) {
- cause++;
- e = WEXITSTATUS(wstat);
- } else if (WIFSIGNALED(wstat)) {
- cause = "signal";
- e = WTERMSIG(wstat);
- }
- printf("%s: info: end %d %s %d\n",
- applet_name, pid, cause, e);
- }
+ if (verbose)
+ print_waitstat(pid, wstat);
}
if (verbose)
connection_status();
int sock;
int conn;
unsigned backlog = 20;
- union {
- struct sockaddr sa;
- struct sockaddr_in sin;
- USE_FEATURE_IPV6(struct sockaddr_in6 sin6;)
- } sock_adr;
- socklen_t sockadr_size;
- uint16_t local_port = local_port;
- uint16_t remote_port;
+ len_and_sockaddr *lsa;
+ uint16_t local_port;
+ uint16_t remote_port = remote_port; /* gcc */
char *local_hostname = NULL;
char *remote_hostname = (char*)""; /* "" used if no -h */
char *local_ip = local_ip; /* gcc */
char *remote_ip = remote_ip; /* gcc */
- //unsigned iscdb = 0; /* = option_mask32 & OPT_x (TODO) */
- //unsigned long timeout = 0;
#ifndef SSLSVD
struct bb_uidgid_t ugid;
#endif
}
if (option_mask32 & OPT_b)
backlog = xatou(str_b);
-// if (option_mask32 & OPT_t) timeout = xatou(str_t);
#ifdef SSLSVD
if (option_mask32 & OPT_U) ssluser = (char*)optarg; break;
if (option_mask32 & OPT_slash) root = (char*)optarg; break;
ipsvd_perhost_init(cmax);
local_port = bb_lookup_port(argv[1], "tcp", 0);
- sock = create_and_bind_stream_or_die(argv[0], local_port);
+ lsa = xhost2sockaddr(argv[0], local_port);
+ sock = xsocket(lsa->sa.sa_family, SOCK_STREAM, 0);
+ setsockopt_reuseaddr(sock); /* desirable */
+ xbind(sock, &lsa->sa, lsa->len);
xlisten(sock, backlog);
/* ndelay_off(sock); - it is the default I think? */
xsetuid(ugid.uid);
}
#endif
- close(0);
if (verbose) {
/* we do it only for ":port" cosmetics... oh well */
- len_and_sockaddr *lsa = xhost2sockaddr(argv[0], local_port);
char *addr = xmalloc_sockaddr2dotted(&lsa->sa, lsa->len);
printf("%s: info: listening on %s", applet_name, addr);
while (cnum >= cmax)
sig_pause(); /* wait for any signal (expecting SIGCHLD) */
- sockadr_size = sizeof(sock_adr);
+ /* Accept a connection to fd #0 */
+ again1:
+ close(0);
+ again2:
sig_unblock(SIGCHLD);
- conn = accept(sock, &sock_adr.sa, &sockadr_size);
+ conn = accept(sock, &lsa->sa, &lsa->len);
sig_block(SIGCHLD);
- if (conn == -1) {
+ if (conn < 0) {
if (errno != EINTR)
bb_perror_msg("accept");
- goto again;
+ goto again2;
}
+ xmove_fd(conn, 0);
if (max_per_host) {
- /* we drop connection immediately if cur_per_host > max_per_host
+ /* Drop connection immediately if cur_per_host > max_per_host
* (minimizing load under SYN flood) */
- remote_ip = xmalloc_sockaddr2dotted_noport(&sock_adr.sa, sockadr_size);
+ remote_ip = xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len);
cur_per_host = ipsvd_perhost_add(remote_ip, max_per_host, &hccp);
if (cur_per_host > max_per_host) {
- free(remote_ip);
/* ipsvd_perhost_add detected that max is exceeded
- * (and did not store us in connection table) */
+ * (and did not store ip in connection table) */
+ free(remote_ip);
if (msg_per_host) {
- ndelay_on(conn);
- /* don't test for errors */
- write(conn, msg_per_host, len_per_host);
+ /* don't block or test for errors */
+ ndelay_on(0);
+ write(0, msg_per_host, len_per_host);
}
- close(conn);
- goto again;
+ goto again1;
}
}
pid = fork();
if (pid == -1) {
bb_perror_msg("fork");
- close(conn);
goto again;
}
if (pid != 0) {
/* parent */
- close(conn);
if (hccp)
hccp->pid = pid;
goto again;
/* Child: prepare env, log, and exec prog */
- close(sock);
-
- if (!max_per_host && need_remote_ip)
- remote_ip = xmalloc_sockaddr2dotted_noport(&sock_adr.sa, sizeof(sock_adr));
- /* else it is already done */
-
- remote_port = get_nport(&sock_adr.sa);
- remote_port = ntohs(remote_port);
-
- if (verbose) {
- pid = getpid();
- printf("%s: info: pid %d from %s\n", applet_name, pid, remote_ip);
- }
-
- if (need_hostnames && (option_mask32 & OPT_h)) {
- remote_hostname = xmalloc_sockaddr2host(&sock_adr.sa, sizeof(sock_adr));
- if (!remote_hostname) {
- bb_error_msg("warning: cannot look up hostname for %s", remote_ip);
- remote_hostname = (char*)"";
- }
+ close(sock); /* listening socket */
+ /* Find out local IP peer connected to.
+ * Errors ignored (I'm not paranoid enough to imagine kernel
+ * which doesn't know local IP). */
+ getsockname(0, &lsa->sa, &lsa->len);
+
+ if (need_remote_ip) {
+ if (!max_per_host)
+ remote_ip = xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len);
+ /* else it is already done */
+ remote_port = get_nport(&lsa->sa);
+ remote_port = ntohs(remote_port);
}
- sockadr_size = sizeof(sock_adr);
- /* Errors ignored (I'm not paranoid enough to imagine kernel
- * which doesn't know local ip) */
- getsockname(conn, &sock_adr.sa, &sockadr_size);
-
if (need_hostnames) {
- local_ip = xmalloc_sockaddr2dotted_noport(&sock_adr.sa, sockadr_size);
- local_port = get_nport(&sock_adr.sa);
+ if (option_mask32 & OPT_h) {
+ remote_hostname = xmalloc_sockaddr2host(&lsa->sa, lsa->len);
+ if (!remote_hostname) {
+ bb_error_msg("warning: cannot look up hostname for %s", remote_ip);
+ remote_hostname = (char*)"";
+ }
+ }
+ local_ip = xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len);
+ local_port = get_nport(&lsa->sa);
local_port = ntohs(local_port);
if (!local_hostname) {
- local_hostname = xmalloc_sockaddr2host_noport(&sock_adr.sa, sockadr_size);
+ local_hostname = xmalloc_sockaddr2host_noport(&lsa->sa, lsa->len);
if (!local_hostname)
bb_error_msg_and_die("cannot look up local hostname for %s", local_ip);
}
}
+ if (verbose) {
+ pid = getpid();
+ printf("%s: info: pid %u from %s\n", applet_name, pid, remote_ip);
+ if (max_per_host)
+ printf("%s: info: concurrency %u %s %u/%u\n",
+ applet_name, pid, remote_ip, cur_per_host, max_per_host);
+ printf("%s: info: start %u %s:%s :%s:%s:%u\n",
+ applet_name, pid,
+ local_hostname, local_ip,
+ remote_hostname, remote_ip, (unsigned)remote_port);
+ }
+
if (!(option_mask32 & OPT_E)) {
/* setup ucspi env */
* from Linux firewall. Useful when you redirect
* an outbond connection to local handler, and it needs
* to know where it originally tried to connect */
- sockadr_size = sizeof(sock_adr);
- if (getsockopt(conn, SOL_IP, SO_ORIGINAL_DST, &sock_adr.sa, &sockadr_size) == 0) {
- char *ip = xmalloc_sockaddr2dotted_noport(&sock_adr.sa, sockadr_size);
- unsigned port = get_nport(&sock_adr.sa);
+ if (getsockopt(0, SOL_IP, SO_ORIGINAL_DST, &lsa->sa, &lsa->len) == 0) {
+ char *ip = xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len);
+ unsigned port = get_nport(&lsa->sa);
port = ntohs(port);
xsetenv("TCPORIGDSTIP", ip);
xsetenv("TCPORIGDSTPORT", utoa(port));
xsetenv("TCPCONCURRENCY", utoa(cur_per_host));
}
-#if 0
- if (instructs) {
- ac = ipsvd_check(iscdb, &inst, &match, (char*)instructs,
- remote_ip, remote_hostname, timeout);
- if (ac == -1) drop2("cannot check inst", remote_ip);
- if (ac == IPSVD_ERR) drop2("cannot read", (char*)instructs);
- } else
- ac = IPSVD_DEFAULT;
-#endif
-
- if (max_per_host && verbose)
- printf("%s: info: concurrency %u %s %u/%u\n",
- applet_name, pid, remote_ip, cur_per_host, max_per_host);
-
- if (verbose) {
- printf("%s: info: start %u %s:%s :%s:%s:%u\n",
- applet_name, pid,
- local_hostname, local_ip,
- remote_hostname, remote_ip, (unsigned)remote_port);
-#if 0
- switch(ac) {
- case IPSVD_DENY:
- printf("deny "); break;
- case IPSVD_DEFAULT:
- case IPSVD_INSTRUCT:
- printf("start "); break;
- case IPSVD_EXEC:
- printf("exec "); break;
- }
- ...
- if (instructs) {
- printf(" ");
- if (iscdb) {
- printf((char*)instructs);
- printf("/");
- }
- outfix(match.s);
- if(inst.s && inst.len && (verbose > 1)) {
- printf(": ");
- printf(&inst);
- }
- }
- printf("\n");
-#endif
- }
-
-#if 0
- if (ac == IPSVD_DENY) {
- close(conn);
- _exit(100);
- }
- if (ac == IPSVD_EXEC) {
- args[0] = "/bin/sh";
- args[1] = "-c";
- args[2] = inst.s;
- args[3] = 0;
- run = args;
- } else
- run = argv + 2; /* below: we use argv+2 (was using run) */
-#endif
-
- xmove_fd(conn, 0);
dup2(0, 1);
signal(SIGTERM, SIG_DFL);
more verbose. Print more verbose messages to standard output.
* no difference between -v and -vv in busyboxed version
*/
+#endif
+++ /dev/null
-/* Based on ipsvd utilities written by Gerrit Pape <pape@smarden.org>
- * which are released into public domain by the author.
- * Homepage: http://smarden.sunsite.dk/ipsvd/
- *
- * Copyright (C) 2007 Denis Vlasenko.
- *
- * Licensed under GPLv2, see file LICENSE in this tarball for details.
- */
-
-/* Based on ipsvd ipsvd-0.12.1. This tcpsvd accepts all options
- * which are supported by one from ipsvd-0.12.1, but not all are
- * functional. See help text at the end of this file for details.
- *
- * Code inside #if 0" is parts of original tcpsvd which are not implemented
- * for busyboxed version.
- *
- * Output of verbose mode matches original (modulo bugs and
- * unimplemented stuff). Unnatural splitting of IP and PORT
- * is retained (personally I prefer one-value "IP:PORT" notation -
- * it is a natural string representation of struct sockaddr_XX).
- */
-
-#include "busybox.h"
-
-#include "udp_io.c"
-
-unsigned verbose;
-
-static void sig_term_handler(int sig)
-{
- if (verbose)
- printf("%s: info: sigterm received, exit\n", applet_name);
- exit(0);
-}
-
-int udpsvd_main(int argc, char **argv);
-int udpsvd_main(int argc, char **argv)
-{
- const char *instructs;
- char *str_t, *user;
- unsigned opt;
-
- char *remote_hostname;
- char *local_hostname = NULL;
- char *remote_ip;
- char *local_ip = local_ip; /* gcc */
- uint16_t local_port, remote_port;
- len_and_sockaddr remote;
- len_and_sockaddr *localp;
- int sock;
- int wstat;
- unsigned pid;
- struct bb_uidgid_t ugid;
-
- enum {
- OPT_v = (1 << 0),
- OPT_u = (1 << 1),
- OPT_l = (1 << 2),
- OPT_h = (1 << 3),
- OPT_p = (1 << 4),
- OPT_i = (1 << 5),
- OPT_x = (1 << 6),
- OPT_t = (1 << 7),
- };
-
- opt_complementary = "-3:ph:vv";
- opt = getopt32(argc, argv, "vu:l:hpi:x:t:",
- &user, &local_hostname, &instructs, &instructs, &str_t, &verbose);
- //if (opt & OPT_x) iscdb =1;
- //if (opt & OPT_t) timeout = xatou(str_t);
- if (!(opt & OPT_h))
- remote_hostname = (char *)"";
- if (opt & OPT_u) {
- if (!get_uidgid(&ugid, user, 1))
- bb_error_msg_and_die("unknown user/group: %s", user);
- }
- argv += optind;
- if (!argv[0][0] || LONE_CHAR(argv[0], '0'))
- argv[0] = (char*)"0.0.0.0";
-
- /* stdout is used for logging, don't buffer */
- setlinebuf(stdout);
- bb_sanitize_stdio(); /* fd# 1,2 must be opened */
-
- signal(SIGTERM, sig_term_handler);
- signal(SIGPIPE, SIG_IGN);
-
- local_port = bb_lookup_port(argv[1], "udp", 0);
- localp = xhost2sockaddr(argv[0], local_port);
- sock = xsocket(localp->sa.sa_family, SOCK_DGRAM, 0);
- xmove_fd(sock, 0); /* fd# 0 is the open UDP socket */
- xbind(0, &localp->sa, localp->len);
- socket_want_pktinfo(0);
-
- if (opt & OPT_u) { /* drop permissions */
- xsetgid(ugid.gid);
- xsetuid(ugid.uid);
- }
-
- if (verbose) {
- /* we do it only for ":port" cosmetics... oh well */
- char *addr = xmalloc_sockaddr2dotted(&localp->sa, localp->len);
- printf("%s: info: listening on %s", applet_name, addr);
- free(addr);
- if (option_mask32 & OPT_u)
- printf(", uid %u, gid %u",
- (unsigned)ugid.uid, (unsigned)ugid.gid);
- puts(", starting");
- }
-
- again:
- /* if (recvfrom(0, NULL, 0, MSG_PEEK, &remote.sa, &localp->len) < 0) { */
- if (recv_from_to(0, NULL, 0, MSG_PEEK, &remote.sa, &localp->sa, localp->len) < 0) {
- bb_perror_msg("recvfrom");
- goto again;
- }
-
- while ((pid = fork()) < 0) {
- bb_perror_msg("fork failed, sleeping");
- sleep(5);
- }
- if (pid > 0) { /* parent */
- while (wait_pid(&wstat, pid) == -1)
- bb_perror_msg("error waiting for child");
- if (verbose)
- printf("%s: info: end %u\n", applet_name, pid);
- goto again;
- }
-
- /* Child */
-
-#if 0
- /* I'd like to make it so that local addr is fixed to localp->sa,
- * but how? The below trick doesn't work... */
- close(0);
- set_nport(localp, htons(local_port));
- xmove_fd(xsocket(localp->sa.sa_family, SOCK_DGRAM, 0), 0);
- xbind(0, &localp->sa, localp->len);
-#endif
-
- if (verbose) {
- local_ip = xmalloc_sockaddr2dotted_noport(&localp->sa, localp->len);
- if (!local_hostname) {
- local_hostname = xmalloc_sockaddr2host_noport(&localp->sa, localp->len);
- if (!local_hostname)
- bb_error_msg_and_die("cannot look up local hostname for %s", local_ip);
- }
- }
-
- remote_ip = xmalloc_sockaddr2dotted_noport(&remote.sa, localp->len);
- remote_port = get_nport(&remote.sa);
- remote_port = ntohs(remote_port);
- if (verbose)
- printf("%s: info: pid %u from %s\n", applet_name, pid, remote_ip);
-
- if (opt & OPT_h) {
- remote_hostname = xmalloc_sockaddr2host(&remote.sa, localp->len);
- if (!remote_hostname) {
- bb_error_msg("warning: cannot look up hostname for %s", remote_ip);
- remote_hostname = (char*)"";
- }
- }
-
-#if 0
- if (instructs) {
- ac = ipsvd_check(iscdb, &inst, &match, (char*)instructs,
- remote_ip, remote_hostname.s, timeout);
- if (ac == -1) discard("unable to check inst", remote_ip);
- if (ac == IPSVD_ERR) discard("unable to read", (char*)instructs);
- } else
- ac = IPSVD_DEFAULT;
-#endif
-
- if (verbose) {
-#if 0
- out("%s: info: ", applet_name);
- switch(ac) {
- case IPSVD_DENY: out("deny "); break;
- case IPSVD_DEFAULT: case IPSVD_INSTRUCT: out("start "); break;
- case IPSVD_EXEC: out("exec "); break;
- }
-#endif
- printf("%s: info: %u %s:%s :%s:%s:%u\n",
- applet_name, pid, local_hostname, local_ip,
- remote_hostname, remote_ip, remote_port);
-#if 0
- if (instructs) {
- out(" ");
- if (iscdb) {
- out((char*)instructs); out("/");
- }
- outfix(match.s);
- if(inst.s && inst.len && (verbose > 1)) {
- out(": "); outinst(&inst);
- }
- }
-#endif
- }
-
-#if 0
- if (ac == IPSVD_DENY) {
- recv(0, 0, 0, 0);
- _exit(100);
- }
- if (ac == IPSVD_EXEC) {
- args[0] = "/bin/sh";
- args[1] = "-c";
- args[2] = inst.s;
- args[3] = NULL;
- run = args;
- } else run = prog;
-#endif
- /* Make plain write(1) work for the child by supplying default
- * destination address */
- xconnect(0, &remote.sa, localp->len);
- dup2(0, 1);
-
- signal(SIGTERM, SIG_DFL);
- signal(SIGPIPE, SIG_DFL);
-
- argv += 2;
- BB_EXECVP(argv[0], argv);
- bb_perror_msg_and_die("exec '%s'", argv[0]);
-}
-
-/*
-udpsvd [-hpvv] [-u user] [-l name] [-i dir|-x cdb] [-t sec] host port prog
-
-udpsvd creates an UDP/IP socket, binds it to the address host:port,
-and listens on the socket for incoming datagrams.
-
-If a datagram is available on the socket, udpsvd conditionally starts
-a program, with standard input reading from the socket, and standard
-output redirected to standard error, to handle this, and possibly
-more datagrams. udpsvd does not start the program if another program
-that it has started before still is running. If the program exits,
-udpsvd again listens to the socket until a new datagram is available.
-If there are still datagrams available on the socket, the program
-is restarted immediately.
-
-udpsvd optionally checks for special intructions depending on
-the IP address or hostname of the client sending the datagram which
-not yet was handled by a running program, see ipsvd-instruct(5)
-for details.
-
-Attention:
-UDP is a connectionless protocol. Most programs that handle user datagrams,
-such as talkd(8), keep running after receiving a datagram, and process
-subsequent datagrams sent to the socket until a timeout is reached.
-udpsvd only checks special instructions for a datagram that causes a startup
-of the program; not if a program handling datagrams already is running.
-It doesn't make much sense to restrict access through special instructions
-when using such a program.
-
-On the other hand, it makes perfectly sense with programs like tftpd(8),
-that fork to establish a separate connection to the client when receiving
-the datagram. In general it's adequate to set up special instructions for
-programs that support being run by tcpwrapper.
-Options
-
-host
- host either is a hostname, or a dotted-decimal IP address, or 0.
- If host is 0, udpsvd accepts datagrams to any local IP address.
-port
- udpsvd accepts datagrams to host:port. port may be a name from
- /etc/services or a number.
-prog
- prog consists of one or more arguments. udpsvd normally runs prog
- to handle a datagram, and possibly more, that is sent to the socket,
- if there is no program that was started before by udpsvd still running
- and handling datagrams.
--i dir
- read instructions for handling new connections from the instructions
- directory dir. See ipsvd-instruct(5) for details.
--x cdb
- read instructions for handling new connections from the constant
- database cdb. The constant database normally is created from
- an instructions directory by running ipsvd-cdb(8).
--t sec
- timeout. This option only takes effect if the -i option is given.
- While checking the instructions directory, check the time of last
- access of the file that matches the clients address or hostname if any,
- discard and remove the file if it wasn't accessed within the last
- sec seconds; udpsvd does not discard or remove a file if the user's
- write permission is not set, for those files the timeout is disabled.
- Default is 0, which means that the timeout is disabled.
--l name
- local hostname. Do not look up the local hostname in DNS, but use name
- as hostname. By default udpsvd looks up the local hostname once at startup.
--u user[:group]
- drop permissions. Switch user ID to user's UID, and group ID to user's
- primary GID after creating and binding to the socket. If user
- is followed by a colon and a group name, the group ID is switched
- to the GID of group instead. All supplementary groups are removed.
--h
- Look up the client's hostname in DNS.
--p
- paranoid. After looking up the client's hostname in DNS, look up
- the IP addresses in DNS for that hostname, and forget the hostname
- if none of the addresses match the client's IP address. You should
- set this option if you use hostname based instructions. The -p option
- implies the -h option.
--v
- verbose. Print verbose messages to standard output.
--vv
- more verbose. Print more verbose messages to standard output.
-*/
projects / platform / upstream / busybox.git / commitdiff