# Licensed under the GPL v2, see the file LICENSE in this tarball.
lib-y:=
-lib-$(CONFIG_TCPSVD) += tcpsvd.o ipsvd_perhost.o
-lib-$(CONFIG_UDPSVD) += udpsvd.o
+lib-$(CONFIG_TCPSVD) += tcpudp.o ipsvd_perhost.o
+lib-$(CONFIG_UDPSVD) += tcpudp.o ipsvd_perhost.o
+++ /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 "#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
- * is retained (personally I prefer one-value "IP:PORT" notation -
- * it is a natural string representation of struct sockaddr_XX).
- *
- * TCPORIGDST{IP,PORT} is busybox-specific addition
- */
-
-#include <limits.h>
-#include <linux/netfilter_ipv4.h> /* wants <limits.h> */
-#include "busybox.h"
-#include "ipsvd_perhost.h"
-
-#ifdef SSLSVD
-#include "matrixSsl.h"
-#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;
-
-/* Must match getopt32 in main! */
-enum {
- OPT_c = (1 << 0),
- OPT_C = (1 << 1),
- OPT_i = (1 << 2),
- OPT_x = (1 << 3),
- OPT_u = (1 << 4),
- OPT_l = (1 << 5),
- OPT_E = (1 << 6),
- OPT_b = (1 << 7),
- OPT_h = (1 << 8),
- OPT_p = (1 << 9),
- OPT_t = (1 << 10),
- OPT_v = (1 << 11),
- OPT_V = (1 << 12),
- OPT_U = (1 << 13), /* from here: sslsvd only */
- OPT_slash = (1 << 14),
- OPT_Z = (1 << 15),
- OPT_K = (1 << 16),
-};
-
-static void connection_status(void)
-{
- 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;
- int pid;
-
- while ((pid = wait_nohang(&wstat)) > 0) {
- if (max_per_host)
- 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)
- connection_status();
-}
-
-int tcpsvd_main(int argc, char **argv);
-int tcpsvd_main(int argc, char **argv)
-{
- char *str_c, *str_C, *str_b, *str_t;
- char *user;
- struct hcc *hccp;
- const char *instructs;
- char *msg_per_host = NULL;
- unsigned len_per_host = len_per_host; /* gcc */
- int need_hostnames, need_remote_ip;
- int pid;
- 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;
- 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
-
- /* 3+ args, -i at most once, -p implies -h, -v is counter */
- opt_complementary = "-3:?:i--i:ph:vv";
-#ifdef SSLSVD
- getopt32(argc, argv, "c:C:i:x:u:l:Eb:hpt:vU:/:Z:K:",
- &str_c, &str_C, &instructs, &instructs, &user, &local_hostname,
- &str_b, &str_t, &ssluser, &root, &cert, &key, &verbose
- );
-#else
- getopt32(argc, argv, "c:C:i:x:u:l:Eb:hpt:v",
- &str_c, &str_C, &instructs, &instructs, &user, &local_hostname,
- &str_b, &str_t, &verbose
- );
-#endif
- if (option_mask32 & OPT_c)
- cmax = xatou_range(str_c, 1, INT_MAX);
- if (option_mask32 & OPT_C) { /* -C n[:message] */
- max_per_host = bb_strtou(str_C, &str_C, 10);
- if (str_C[0]) {
- if (str_C[0] != ':')
- bb_show_usage();
- msg_per_host = str_C + 1;
- len_per_host = strlen(msg_per_host);
- }
- }
- if (max_per_host > cmax)
- max_per_host = cmax;
- if (option_mask32 & OPT_u) {
- if (!get_uidgid(&ugid, user, 1))
- bb_error_msg_and_die("unknown user/group: %s", user);
- }
- 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;
- if (option_mask32 & OPT_Z) cert = (char*)optarg; break;
- if (option_mask32 & OPT_K) key = (char*)optarg; break;
-#endif
- 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 */
-
- need_hostnames = verbose || !(option_mask32 & OPT_E);
- need_remote_ip = max_per_host || need_hostnames;
-
-#ifdef SSLSVD
- sslser = user;
- client = 0;
- if ((getuid() == 0) && !(option_mask32 & OPT_u)) {
- xfunc_exitcode = 100;
- bb_error_msg_and_die("fatal: -U ssluser must be set when running as root");
- }
- if (option_mask32 & OPT_u)
- if (!uidgid_get(&sslugid, ssluser, 1)) {
- if (errno) {
- xfunc_exitcode = 100;
- bb_perror_msg_and_die("fatal: cannot get user/group: %s", ssluser);
- }
- xfunc_exitcode = 111;
- bb_error_msg_and_die("fatal: unknown user/group '%s'", ssluser);
- }
- if (!cert) cert = "./cert.pem";
- if (!key) key = cert;
- if (matrixSslOpen() < 0)
- fatal("cannot initialize ssl");
- if (matrixSslReadKeys(&keys, cert, key, 0, ca) < 0) {
- if (client)
- fatal("cannot read cert, key, or ca file");
- fatal("cannot read cert or key file");
- }
- if (matrixSslNewSession(&ssl, keys, 0, SSL_FLAGS_SERVER) < 0)
- fatal("cannot create ssl session");
-#endif
-
- sig_block(SIGCHLD);
- signal(SIGCHLD, sig_child_handler);
- signal(SIGTERM, sig_term_handler);
- signal(SIGPIPE, SIG_IGN);
-
- if (max_per_host)
- ipsvd_perhost_init(cmax);
-
- local_port = bb_lookup_port(argv[1], "tcp", 0);
- sock = create_and_bind_stream_or_die(argv[0], local_port);
- xlisten(sock, backlog);
- /* ndelay_off(sock); - it is the default I think? */
-
-#ifndef SSLSVD
- if (option_mask32 & OPT_u) {
- /* drop permissions */
- xsetgid(ugid.gid);
- 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);
- free(addr);
-#ifndef SSLSVD
- if (option_mask32 & OPT_u)
- printf(", uid %u, gid %u",
- (unsigned)ugid.uid, (unsigned)ugid.gid);
-#endif
- puts(", starting");
- }
-
- /* The rest is a main accept() loop */
-
- again:
- hccp = NULL;
-
- while (cnum >= cmax)
- sig_pause(); /* wait for any signal (expecting SIGCHLD) */
-
- sockadr_size = sizeof(sock_adr);
- sig_unblock(SIGCHLD);
- conn = accept(sock, &sock_adr.sa, &sockadr_size);
- sig_block(SIGCHLD);
- if (conn == -1) {
- if (errno != EINTR)
- bb_perror_msg("accept");
- goto again;
- }
-
- if (max_per_host) {
- /* we 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);
- 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) */
- if (msg_per_host) {
- ndelay_on(conn);
- /* don't test for errors */
- write(conn, msg_per_host, len_per_host);
- }
- close(conn);
- goto again;
- }
- }
-
- cnum++;
- if (verbose)
- connection_status();
-
- 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*)"";
- }
- }
-
- 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);
- local_port = ntohs(local_port);
- if (!local_hostname) {
- local_hostname = xmalloc_sockaddr2host_noport(&sock_adr.sa, sockadr_size);
- if (!local_hostname)
- bb_error_msg_and_die("cannot look up local hostname for %s", local_ip);
- }
- }
-
- if (!(option_mask32 & OPT_E)) {
- /* setup ucspi env */
-
- /* Extract "original" destination addr:port
- * 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);
- port = ntohs(port);
- xsetenv("TCPORIGDSTIP", ip);
- xsetenv("TCPORIGDSTPORT", utoa(port));
- free(ip);
- }
- xsetenv("PROTO", "TCP");
- xsetenv("TCPLOCALIP", local_ip);
- xsetenv("TCPLOCALPORT", utoa(local_port));
- xsetenv("TCPLOCALHOST", local_hostname);
- xsetenv("TCPREMOTEIP", remote_ip);
- xsetenv("TCPREMOTEPORT", utoa(remote_port));
- if (option_mask32 & OPT_h) {
- xsetenv("TCPREMOTEHOST", remote_hostname);
- }
- xsetenv("TCPREMOTEINFO", "");
- /* additional */
- if (cur_per_host > 0)
- 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);
- signal(SIGPIPE, SIG_DFL);
- signal(SIGCHLD, SIG_DFL);
- sig_unblock(SIGCHLD);
-
- argv += 2;
-#ifdef SSLSVD
- strcpy(id, utoa(pid);
- ssl_io(0, argv);
-#else
- BB_EXECVP(argv[0], argv);
-#endif
- bb_perror_msg_and_die("exec '%s'", argv[0]);
-}
-
-/*
-tcpsvd [-hpEvv] [-c n] [-C n:msg] [-b n] [-u user] [-l name]
- [-i dir|-x cdb] [ -t sec] host port prog
-
-tcpsvd creates a TCP/IP socket, binds it to the address host:port,
-and listens on the socket for incoming connections.
-
-On each incoming connection, tcpsvd conditionally runs a program,
-with standard input reading from the socket, and standard output
-writing to the socket, to handle this connection. tcpsvd keeps
-listening on the socket for new connections, and can handle
-multiple connections simultaneously.
-
-tcpsvd optionally checks for special instructions depending
-on the IP address or hostname of the client that initiated
-the connection, see ipsvd-instruct(5).
-
-host
- host either is a hostname, or a dotted-decimal IP address,
- or 0. If host is 0, tcpsvd accepts connections to any local
- IP address.
- * busybox accepts IPv6 addresses and host:port pairs too
- In this case second parameter is ignored
-port
- tcpsvd accepts connections to host:port. port may be a name
- from /etc/services or a number.
-prog
- prog consists of one or more arguments. For each connection,
- tcpsvd normally runs prog, with file descriptor 0 reading from
- the network, and file descriptor 1 writing to the network.
- By default it also sets up TCP-related environment variables,
- see tcp-environ(5)
--i dir
- read instructions for handling new connections from the instructions
- directory dir. See ipsvd-instruct(5) for details.
- * ignored by busyboxed version
--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).
- * ignored by busyboxed version
--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;
- tcpsvd 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.
- * ignored by busyboxed version
--l name
- local hostname. Do not look up the local hostname in DNS, but use name
- as hostname. This option must be set if tcpsvd listens on port 53
- to avoid loops.
--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.
--c n
- concurrency. Handle up to n connections simultaneously. Default is 30.
- If there are n connections active, tcpsvd defers acceptance of a new
- connection until an active connection is closed.
--C n[:msg]
- per host concurrency. Allow only up to n connections from the same IP
- address simultaneously. If there are n active connections from one IP
- address, new incoming connections from this IP address are closed
- immediately. If n is followed by :msg, the message msg is written
- to the client if possible, before closing the connection. By default
- msg is empty. See ipsvd-instruct(5) for supported escape sequences in msg.
-
- For each accepted connection, the current per host concurrency is
- available through the environment variable TCPCONCURRENCY. n and msg
- can be overwritten by ipsvd(7) instructions, see ipsvd-instruct(5).
- By default tcpsvd doesn't keep track of connections.
--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 about 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.
- * ignored by busyboxed version
--b n
- backlog. Allow a backlog of approximately n TCP SYNs. On some systems n
- is silently limited. Default is 20.
--E
- no special environment. Do not set up TCP-related environment variables.
--v
- verbose. Print verbose messsages to standard output.
--vv
- more verbose. Print more verbose messages to standard output.
- * no difference between -v and -vv in busyboxed version
-*/
--- /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.
+ */
+
+/* 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.
+ *
+ * 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).
+ *
+ * TCPORIGDST{IP,PORT} is busybox-specific addition
+ */
+
+#include <limits.h>
+#include <linux/netfilter_ipv4.h> /* wants <limits.h> */
+#include "ipsvd_perhost.h"
+
+#ifdef SSLSVD
+#include "matrixSsl.h"
+#include "ssl_io.h"
+#endif
+
+static unsigned max_per_host; /* originally in ipsvd_check.c */
+static unsigned cur_per_host;
+static unsigned cnum;
+static unsigned cmax = 30;
+
+/* Must match getopt32 in main! */
+enum {
+ OPT_c = (1 << 0),
+ OPT_C = (1 << 1),
+ OPT_i = (1 << 2),
+ OPT_x = (1 << 3),
+ OPT_u = (1 << 4),
+ OPT_l = (1 << 5),
+ OPT_E = (1 << 6),
+ OPT_b = (1 << 7),
+ OPT_h = (1 << 8),
+ OPT_p = (1 << 9),
+ OPT_t = (1 << 10),
+ OPT_v = (1 << 11),
+ OPT_V = (1 << 12),
+ OPT_U = (1 << 13), /* from here: sslsvd only */
+ OPT_slash = (1 << 14),
+ OPT_Z = (1 << 15),
+ OPT_K = (1 << 16),
+};
+
+static void connection_status(void)
+{
+ printf("%s: info: status %u/%u\n", applet_name, cnum, cmax);
+}
+
+static void sig_child_handler(int sig)
+{
+ int wstat;
+ int pid;
+
+ while ((pid = wait_nohang(&wstat)) > 0) {
+ if (max_per_host)
+ ipsvd_perhost_remove(pid);
+ if (cnum)
+ cnum--;
+ if (verbose)
+ print_waitstat(pid, wstat);
+ }
+ if (verbose)
+ connection_status();
+}
+
+int tcpsvd_main(int argc, char **argv);
+int tcpsvd_main(int argc, char **argv)
+{
+ char *str_c, *str_C, *str_b, *str_t;
+ char *user;
+ struct hcc *hccp;
+ const char *instructs;
+ char *msg_per_host = NULL;
+ unsigned len_per_host = len_per_host; /* gcc */
+ int need_hostnames, need_remote_ip;
+ int pid;
+ int sock;
+ int conn;
+ unsigned backlog = 20;
+ 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 */
+#ifndef SSLSVD
+ struct bb_uidgid_t ugid;
+#endif
+
+ /* 3+ args, -i at most once, -p implies -h, -v is counter */
+ opt_complementary = "-3:?:i--i:ph:vv";
+#ifdef SSLSVD
+ getopt32(argc, argv, "c:C:i:x:u:l:Eb:hpt:vU:/:Z:K:",
+ &str_c, &str_C, &instructs, &instructs, &user, &local_hostname,
+ &str_b, &str_t, &ssluser, &root, &cert, &key, &verbose
+ );
+#else
+ getopt32(argc, argv, "c:C:i:x:u:l:Eb:hpt:v",
+ &str_c, &str_C, &instructs, &instructs, &user, &local_hostname,
+ &str_b, &str_t, &verbose
+ );
+#endif
+ if (option_mask32 & OPT_c)
+ cmax = xatou_range(str_c, 1, INT_MAX);
+ if (option_mask32 & OPT_C) { /* -C n[:message] */
+ max_per_host = bb_strtou(str_C, &str_C, 10);
+ if (str_C[0]) {
+ if (str_C[0] != ':')
+ bb_show_usage();
+ msg_per_host = str_C + 1;
+ len_per_host = strlen(msg_per_host);
+ }
+ }
+ if (max_per_host > cmax)
+ max_per_host = cmax;
+ if (option_mask32 & OPT_u) {
+ if (!get_uidgid(&ugid, user, 1))
+ bb_error_msg_and_die("unknown user/group: %s", user);
+ }
+ if (option_mask32 & OPT_b)
+ backlog = xatou(str_b);
+#ifdef SSLSVD
+ if (option_mask32 & OPT_U) ssluser = (char*)optarg; break;
+ if (option_mask32 & OPT_slash) root = (char*)optarg; break;
+ if (option_mask32 & OPT_Z) cert = (char*)optarg; break;
+ if (option_mask32 & OPT_K) key = (char*)optarg; break;
+#endif
+ 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 */
+
+ need_hostnames = verbose || !(option_mask32 & OPT_E);
+ need_remote_ip = max_per_host || need_hostnames;
+
+#ifdef SSLSVD
+ sslser = user;
+ client = 0;
+ if ((getuid() == 0) && !(option_mask32 & OPT_u)) {
+ xfunc_exitcode = 100;
+ bb_error_msg_and_die("fatal: -U ssluser must be set when running as root");
+ }
+ if (option_mask32 & OPT_u)
+ if (!uidgid_get(&sslugid, ssluser, 1)) {
+ if (errno) {
+ xfunc_exitcode = 100;
+ bb_perror_msg_and_die("fatal: cannot get user/group: %s", ssluser);
+ }
+ xfunc_exitcode = 111;
+ bb_error_msg_and_die("fatal: unknown user/group '%s'", ssluser);
+ }
+ if (!cert) cert = "./cert.pem";
+ if (!key) key = cert;
+ if (matrixSslOpen() < 0)
+ fatal("cannot initialize ssl");
+ if (matrixSslReadKeys(&keys, cert, key, 0, ca) < 0) {
+ if (client)
+ fatal("cannot read cert, key, or ca file");
+ fatal("cannot read cert or key file");
+ }
+ if (matrixSslNewSession(&ssl, keys, 0, SSL_FLAGS_SERVER) < 0)
+ fatal("cannot create ssl session");
+#endif
+
+ sig_block(SIGCHLD);
+ signal(SIGCHLD, sig_child_handler);
+ signal(SIGTERM, sig_term_handler);
+ signal(SIGPIPE, SIG_IGN);
+
+ if (max_per_host)
+ ipsvd_perhost_init(cmax);
+
+ local_port = bb_lookup_port(argv[1], "tcp", 0);
+ 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? */
+
+#ifndef SSLSVD
+ if (option_mask32 & OPT_u) {
+ /* drop permissions */
+ xsetgid(ugid.gid);
+ xsetuid(ugid.uid);
+ }
+#endif
+
+ if (verbose) {
+ /* we do it only for ":port" cosmetics... oh well */
+ char *addr = xmalloc_sockaddr2dotted(&lsa->sa, lsa->len);
+
+ printf("%s: info: listening on %s", applet_name, addr);
+ free(addr);
+#ifndef SSLSVD
+ if (option_mask32 & OPT_u)
+ printf(", uid %u, gid %u",
+ (unsigned)ugid.uid, (unsigned)ugid.gid);
+#endif
+ puts(", starting");
+ }
+
+ /* The rest is a main accept() loop */
+
+ again:
+ hccp = NULL;
+
+ while (cnum >= cmax)
+ sig_pause(); /* wait for any signal (expecting SIGCHLD) */
+
+ /* Accept a connection to fd #0 */
+ again1:
+ close(0);
+ again2:
+ sig_unblock(SIGCHLD);
+ conn = accept(sock, &lsa->sa, &lsa->len);
+ sig_block(SIGCHLD);
+ if (conn < 0) {
+ if (errno != EINTR)
+ bb_perror_msg("accept");
+ goto again2;
+ }
+ xmove_fd(conn, 0);
+
+ if (max_per_host) {
+ /* Drop connection immediately if cur_per_host > max_per_host
+ * (minimizing load under SYN flood) */
+ 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) {
+ /* ipsvd_perhost_add detected that max is exceeded
+ * (and did not store ip in connection table) */
+ free(remote_ip);
+ if (msg_per_host) {
+ /* don't block or test for errors */
+ ndelay_on(0);
+ write(0, msg_per_host, len_per_host);
+ }
+ goto again1;
+ }
+ }
+
+ cnum++;
+ if (verbose)
+ connection_status();
+
+ pid = fork();
+ if (pid == -1) {
+ bb_perror_msg("fork");
+ goto again;
+ }
+ if (pid != 0) {
+ /* parent */
+ if (hccp)
+ hccp->pid = pid;
+ goto again;
+ }
+
+ /* Child: prepare env, log, and exec prog */
+
+ 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);
+ }
+
+ if (need_hostnames) {
+ 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(&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 */
+
+ /* Extract "original" destination addr:port
+ * from Linux firewall. Useful when you redirect
+ * an outbond connection to local handler, and it needs
+ * to know where it originally tried to connect */
+ 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));
+ free(ip);
+ }
+ xsetenv("PROTO", "TCP");
+ xsetenv("TCPLOCALIP", local_ip);
+ xsetenv("TCPLOCALPORT", utoa(local_port));
+ xsetenv("TCPLOCALHOST", local_hostname);
+ xsetenv("TCPREMOTEIP", remote_ip);
+ xsetenv("TCPREMOTEPORT", utoa(remote_port));
+ if (option_mask32 & OPT_h) {
+ xsetenv("TCPREMOTEHOST", remote_hostname);
+ }
+ xsetenv("TCPREMOTEINFO", "");
+ /* additional */
+ if (cur_per_host > 0)
+ xsetenv("TCPCONCURRENCY", utoa(cur_per_host));
+ }
+
+ dup2(0, 1);
+
+ signal(SIGTERM, SIG_DFL);
+ signal(SIGPIPE, SIG_DFL);
+ signal(SIGCHLD, SIG_DFL);
+ sig_unblock(SIGCHLD);
+
+ argv += 2;
+#ifdef SSLSVD
+ strcpy(id, utoa(pid);
+ ssl_io(0, argv);
+#else
+ BB_EXECVP(argv[0], argv);
+#endif
+ bb_perror_msg_and_die("exec '%s'", argv[0]);
+}
+
+/*
+tcpsvd [-hpEvv] [-c n] [-C n:msg] [-b n] [-u user] [-l name]
+ [-i dir|-x cdb] [ -t sec] host port prog
+
+tcpsvd creates a TCP/IP socket, binds it to the address host:port,
+and listens on the socket for incoming connections.
+
+On each incoming connection, tcpsvd conditionally runs a program,
+with standard input reading from the socket, and standard output
+writing to the socket, to handle this connection. tcpsvd keeps
+listening on the socket for new connections, and can handle
+multiple connections simultaneously.
+
+tcpsvd optionally checks for special instructions depending
+on the IP address or hostname of the client that initiated
+the connection, see ipsvd-instruct(5).
+
+host
+ host either is a hostname, or a dotted-decimal IP address,
+ or 0. If host is 0, tcpsvd accepts connections to any local
+ IP address.
+ * busybox accepts IPv6 addresses and host:port pairs too
+ In this case second parameter is ignored
+port
+ tcpsvd accepts connections to host:port. port may be a name
+ from /etc/services or a number.
+prog
+ prog consists of one or more arguments. For each connection,
+ tcpsvd normally runs prog, with file descriptor 0 reading from
+ the network, and file descriptor 1 writing to the network.
+ By default it also sets up TCP-related environment variables,
+ see tcp-environ(5)
+-i dir
+ read instructions for handling new connections from the instructions
+ directory dir. See ipsvd-instruct(5) for details.
+ * ignored by busyboxed version
+-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).
+ * ignored by busyboxed version
+-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;
+ tcpsvd 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.
+ * ignored by busyboxed version
+-l name
+ local hostname. Do not look up the local hostname in DNS, but use name
+ as hostname. This option must be set if tcpsvd listens on port 53
+ to avoid loops.
+-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.
+-c n
+ concurrency. Handle up to n connections simultaneously. Default is 30.
+ If there are n connections active, tcpsvd defers acceptance of a new
+ connection until an active connection is closed.
+-C n[:msg]
+ per host concurrency. Allow only up to n connections from the same IP
+ address simultaneously. If there are n active connections from one IP
+ address, new incoming connections from this IP address are closed
+ immediately. If n is followed by :msg, the message msg is written
+ to the client if possible, before closing the connection. By default
+ msg is empty. See ipsvd-instruct(5) for supported escape sequences in msg.
+
+ For each accepted connection, the current per host concurrency is
+ available through the environment variable TCPCONCURRENCY. n and msg
+ can be overwritten by ipsvd(7) instructions, see ipsvd-instruct(5).
+ By default tcpsvd doesn't keep track of connections.
+-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 about 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.
+ * ignored by busyboxed version
+-b n
+ backlog. Allow a backlog of approximately n TCP SYNs. On some systems n
+ is silently limited. Default is 20.
+-E
+ no special environment. Do not set up TCP-related environment variables.
+-v
+ verbose. Print verbose messsages to standard output.
+-vv
+ 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 / oweals / busybox.git / commitdiff