/* * Copyright (c) 1983, 1991, 1993, 1994 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint static char copyright[] = "@(#) Copyright (c) 1983, 1991, 1993, 1994\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint /* from: @(#)inetd.c 8.4 (Berkeley) 4/13/94"; */ static char inetd_c_rcsid[] = "$Id: inetd.c,v 1.12 1996/07/17 15:00:28 davidg Exp $"; #endif /* not lint */ /* * Inetd - Internet super-server * * This program invokes all internet services as needed. Connection-oriented * services are invoked each time a connection is made, by creating a process. * This process is passed the connection as file descriptor 0 and is expected * to do a getpeername to find out the source host and port. * * Datagram oriented services are invoked when a datagram * arrives; a process is created and passed a pending message * on file descriptor 0. Datagram servers may either connect * to their peer, freeing up the original socket for inetd * to receive further messages on, or ``take over the socket'', * processing all arriving datagrams and, eventually, timing * out. The first type of server is said to be ``multi-threaded''; * the second type of server ``single-threaded''. * * Inetd uses a configuration file which is read at startup * and, possibly, at some later time in response to a hangup signal. * The configuration file is ``free format'' with fields given in the * order shown below. Continuation lines for an entry must being with * a space or tab. All fields must be present in each entry. * * service name must be in /etc/services or must * name a tcpmux service * socket type stream/dgram/raw/rdm/seqpacket * protocol must be in /etc/protocols * wait/nowait single-threaded/multi-threaded * user user to run daemon as * server program full path name * server program arguments maximum of MAXARGS (20) * * TCP services without official port numbers are handled with the * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for * requests. When a connection is made from a foreign host, the service * requested is passed to tcpmux, which looks it up in the servtab list * and returns the proper entry for the service. Tcpmux returns a * negative reply if the service doesn't exist, otherwise the invoked * server is expected to return the positive reply if the service type in * inetd.conf file has the prefix "tcpmux/". If the service type has the * prefix "tcpmux/+", tcpmux will return the positive reply for the * process; this is for compatibility with older server code, and also * allows you to invoke programs that use stdin/stdout without putting any * special server code in them. Services that use tcpmux are "nowait" * because they do not have a well-known port and hence cannot listen * for new requests. * * For RPC services * service name/version must be in /etc/rpc * socket type stream/dgram/raw/rdm/seqpacket * protocol must be in /etc/protocols * wait/nowait single-threaded/multi-threaded * user user to run daemon as * server program full path name * server program arguments maximum of MAXARGS * * Comment lines are indicated by a `#' in column 1. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pathnames.h" #define TOOMANY 256 /* don't start more than TOOMANY */ #define CNT_INTVL 60 /* servers in CNT_INTVL sec. */ #define RETRYTIME (60*10) /* retry after bind or server fail */ #define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM)) int debug = 0; int log = 0; int nsock, maxsock; fd_set allsock; int options; int timingout; int toomany = TOOMANY; struct servent *sp; struct rpcent *rpc; struct in_addr bind_address; struct servtab { char *se_service; /* name of service */ int se_socktype; /* type of socket to use */ char *se_proto; /* protocol used */ short se_wait; /* single threaded server */ short se_checked; /* looked at during merge */ char *se_user; /* user name to run as */ struct biltin *se_bi; /* if built-in, description */ char *se_server; /* server program */ #define MAXARGV 20 char *se_argv[MAXARGV+1]; /* program arguments */ int se_fd; /* open descriptor */ int se_type; /* type */ struct sockaddr_in se_ctrladdr;/* bound address */ int se_rpc; /* ==1 if RPC service */ int se_rpc_prog; /* RPC program number */ u_int se_rpc_lowvers; /* RPC low version */ u_int se_rpc_highvers; /* RPC high version */ int se_count; /* number started since se_time */ struct timeval se_time; /* start of se_count */ struct servtab *se_next; } *servtab; #define NORM_TYPE 0 #define MUX_TYPE 1 #define MUXPLUS_TYPE 2 #define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \ ((sep)->se_type == MUXPLUS_TYPE)) #define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE) void chargen_dg __P((int, struct servtab *)); void chargen_stream __P((int, struct servtab *)); void close_sep __P((struct servtab *)); void config __P((int)); void daytime_dg __P((int, struct servtab *)); void daytime_stream __P((int, struct servtab *)); void discard_dg __P((int, struct servtab *)); void discard_stream __P((int, struct servtab *)); void echo_dg __P((int, struct servtab *)); void echo_stream __P((int, struct servtab *)); void endconfig __P((void)); struct servtab *enter __P((struct servtab *)); void freeconfig __P((struct servtab *)); struct servtab *getconfigent __P((void)); void machtime_dg __P((int, struct servtab *)); void machtime_stream __P((int, struct servtab *)); char *newstr __P((char *)); char *nextline __P((FILE *)); void print_service __P((char *, struct servtab *)); void reapchild __P((int)); void retry __P((int)); int setconfig __P((void)); void setup __P((struct servtab *)); char *sskip __P((char **)); char *skip __P((char **)); struct servtab *tcpmux __P((int)); void unregisterrpc __P((register struct servtab *sep)); struct biltin { char *bi_service; /* internally provided service name */ int bi_socktype; /* type of socket supported */ short bi_fork; /* 1 if should fork before call */ short bi_wait; /* 1 if should wait for child */ void (*bi_fn)(); /* function which performs it */ } biltins[] = { /* Echo received data */ { "echo", SOCK_STREAM, 1, 0, echo_stream }, { "echo", SOCK_DGRAM, 0, 0, echo_dg }, /* Internet /dev/null */ { "discard", SOCK_STREAM, 1, 0, discard_stream }, { "discard", SOCK_DGRAM, 0, 0, discard_dg }, /* Return 32 bit time since 1970 */ { "time", SOCK_STREAM, 0, 0, machtime_stream }, { "time", SOCK_DGRAM, 0, 0, machtime_dg }, /* Return human-readable time */ { "daytime", SOCK_STREAM, 0, 0, daytime_stream }, { "daytime", SOCK_DGRAM, 0, 0, daytime_dg }, /* Familiar character generator */ { "chargen", SOCK_STREAM, 1, 0, chargen_stream }, { "chargen", SOCK_DGRAM, 0, 0, chargen_dg }, { "tcpmux", SOCK_STREAM, 1, 0, (void (*)())tcpmux }, { NULL } }; #define NUMINT (sizeof(intab) / sizeof(struct inent)) char *CONFIG = _PATH_INETDCONF; char *pid_file = _PATH_INETDPID; #ifdef OLD_SETPROCTITLE char **Argv; char *LastArg; #endif int main(argc, argv, envp) int argc; char *argv[], *envp[]; { struct servtab *sep; struct passwd *pwd; struct sigvec sv; int tmpint, ch, dofork; pid_t pid; char buf[50]; struct sockaddr_in peer; int i; #ifdef OLD_SETPROCTITLE Argv = argv; if (envp == 0 || *envp == 0) envp = argv; while (*envp) envp++; LastArg = envp[-1] + strlen(envp[-1]); #endif openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON); bind_address.s_addr = htonl(INADDR_ANY); while ((ch = getopt(argc, argv, "dlR:a:p:")) != EOF) switch(ch) { case 'd': debug = 1; options |= SO_DEBUG; break; case 'l': log = 1; break; case 'R': { /* invocation rate */ char *p; tmpint = strtol(optarg, &p, 0); if (tmpint < 1 || *p) syslog(LOG_ERR, "-R %s: bad value for service invocation rate", optarg); else toomany = tmpint; break; } case 'a': if (!inet_aton(optarg, &bind_address)) { syslog(LOG_ERR, "-a %s: invalid IP address", optarg); exit(1); } break; case 'p': pid_file = optarg; break; case '?': default: syslog(LOG_ERR, "usage: inetd [-dl] [-a address] [-R rate]" " [-p pidfile] [conf-file]"); exit(1); } argc -= optind; argv += optind; if (argc > 0) CONFIG = argv[0]; if (debug == 0) { FILE *fp; if (daemon(0, 0) < 0) { syslog(LOG_WARNING, "daemon(0,0) failed: %m"); } /* * In case somebody has started inetd manually, we need to * clear the logname, so that old servers run as root do not * get the user's logname.. */ if (setlogin("") < 0) { syslog(LOG_WARNING, "cannot clear logname: %m"); /* no big deal if it fails.. */ } pid = getpid(); fp = fopen(pid_file, "w"); if (fp) { fprintf(fp, "%ld\n", (long)pid); fclose(fp); } else { syslog(LOG_WARNING, "%s: %m", pid_file); } } memset(&sv, 0, sizeof(sv)); sv.sv_mask = SIGBLOCK; sv.sv_handler = retry; sigvec(SIGALRM, &sv, (struct sigvec *)0); config(SIGHUP); sv.sv_handler = config; sigvec(SIGHUP, &sv, (struct sigvec *)0); sv.sv_handler = reapchild; sigvec(SIGCHLD, &sv, (struct sigvec *)0); { /* space for daemons to overwrite environment for ps */ #define DUMMYSIZE 100 char dummy[DUMMYSIZE]; (void)memset(dummy, 'x', sizeof(DUMMYSIZE) - 1); dummy[DUMMYSIZE - 1] = '\0'; (void)setenv("inetd_dummy", dummy, 1); } for (;;) { int n, ctrl; fd_set readable; if (nsock == 0) { (void) sigblock(SIGBLOCK); while (nsock == 0) sigpause(0L); (void) sigsetmask(0L); } readable = allsock; if ((n = select(maxsock + 1, &readable, (fd_set *)0, (fd_set *)0, (struct timeval *)0)) <= 0) { if (n < 0 && errno != EINTR) syslog(LOG_WARNING, "select: %m"); sleep(1); continue; } for (sep = servtab; n && sep; sep = sep->se_next) if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) { n--; if (debug) fprintf(stderr, "someone wants %s\n", sep->se_service); if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { ctrl = accept(sep->se_fd, (struct sockaddr *)0, (int *)0); if (debug) fprintf(stderr, "accept, ctrl %d\n", ctrl); if (ctrl < 0) { if (errno != EINTR) syslog(LOG_WARNING, "accept (for %s): %m", sep->se_service); continue; } if(log) { i = sizeof peer; if(getpeername(ctrl, (struct sockaddr *) &peer, &i)) { syslog(LOG_WARNING, "getpeername(for %s): %m", sep->se_service); continue; } syslog(LOG_INFO,"%s from %s", sep->se_service, inet_ntoa(peer.sin_addr)); } /* * Call tcpmux to find the real service to exec. */ if (sep->se_bi && sep->se_bi->bi_fn == (void (*)()) tcpmux) { struct servtab *tsep; tsep = tcpmux(ctrl); if (tsep == NULL) { close(ctrl); continue; } sep = tsep; } } else ctrl = sep->se_fd; (void) sigblock(SIGBLOCK); pid = 0; dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); if (dofork) { if (sep->se_count++ == 0) (void)gettimeofday(&sep->se_time, (struct timezone *)0); else if (sep->se_count >= toomany) { struct timeval now; (void)gettimeofday(&now, (struct timezone *)0); if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) { sep->se_time = now; sep->se_count = 1; } else { syslog(LOG_ERR, "%s/%s server failing (looping), service terminated", sep->se_service, sep->se_proto); close_sep(sep); sigsetmask(0L); if (!timingout) { timingout = 1; alarm(RETRYTIME); } continue; } } pid = fork(); } if (pid < 0) { syslog(LOG_ERR, "fork: %m"); if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) close(ctrl); sigsetmask(0L); sleep(1); continue; } if (pid && sep->se_wait) { sep->se_wait = pid; if (sep->se_fd >= 0) { FD_CLR(sep->se_fd, &allsock); nsock--; } } sigsetmask(0L); if (pid == 0) { if (dofork) { if (debug) fprintf(stderr, "+ Closing from %d\n", maxsock); for (tmpint = maxsock; tmpint > 2; tmpint--) if (tmpint != ctrl) close(tmpint); } if (sep->se_bi) (*sep->se_bi->bi_fn)(ctrl, sep); else { if (debug) fprintf(stderr, "%d execl %s\n", getpid(), sep->se_server); dup2(ctrl, 0); close(ctrl); dup2(0, 1); dup2(0, 2); if ((pwd = getpwnam(sep->se_user)) == NULL) { syslog(LOG_ERR, "%s/%s: %s: No such user", sep->se_service, sep->se_proto, sep->se_user); if (sep->se_socktype != SOCK_STREAM) recv(0, buf, sizeof (buf), 0); _exit(1); } if (setsid() < 0) { syslog(LOG_ERR, "%s: can't setsid(): %m", sep->se_service); /* _exit(1); not fatal yet */ } if (pwd->pw_uid) { if (setlogin(sep->se_user) < 0) { syslog(LOG_ERR, "%s: can't setlogin(%s): %m", sep->se_service, sep->se_user); /* _exit(1); not fatal yet */ } if (setgid(pwd->pw_gid) < 0) { syslog(LOG_ERR, "%s: can't set gid %d: %m", sep->se_service, pwd->pw_gid); _exit(1); } (void) initgroups(pwd->pw_name, pwd->pw_gid); if (setuid(pwd->pw_uid) < 0) { syslog(LOG_ERR, "%s: can't set uid %d: %m", sep->se_service, pwd->pw_uid); _exit(1); } } execv(sep->se_server, sep->se_argv); if (sep->se_socktype != SOCK_STREAM) recv(0, buf, sizeof (buf), 0); syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); _exit(1); } } if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) close(ctrl); } } } void reapchild(signo) int signo; { int status; pid_t pid; struct servtab *sep; for (;;) { pid = wait3(&status, WNOHANG, (struct rusage *)0); if (pid <= 0) break; if (debug) fprintf(stderr, "%d reaped, status %#x\n", pid, status); for (sep = servtab; sep; sep = sep->se_next) if (sep->se_wait == pid) { if (status) syslog(LOG_WARNING, "%s: exit status 0x%x", sep->se_server, status); if (debug) fprintf(stderr, "restored %s, fd %d\n", sep->se_service, sep->se_fd); FD_SET(sep->se_fd, &allsock); nsock++; sep->se_wait = 1; } } } void config(signo) int signo; { struct servtab *sep, *cp, **sepp; struct passwd *pwd; long omask; if (!setconfig()) { syslog(LOG_ERR, "%s: %m", CONFIG); return; } for (sep = servtab; sep; sep = sep->se_next) sep->se_checked = 0; while (cp = getconfigent()) { if ((pwd = getpwnam(cp->se_user)) == NULL) { syslog(LOG_ERR, "%s/%s: No such user '%s', service ignored", cp->se_service, cp->se_proto, cp->se_user); continue; } for (sep = servtab; sep; sep = sep->se_next) if (strcmp(sep->se_service, cp->se_service) == 0 && strcmp(sep->se_proto, cp->se_proto) == 0) break; if (sep != 0) { int i; omask = sigblock(SIGBLOCK); /* * sep->se_wait may be holding the pid of a daemon * that we're waiting for. If so, don't overwrite * it unless the config file explicitly says don't * wait. */ if (cp->se_bi == 0 && (sep->se_wait == 1 || cp->se_wait == 0)) sep->se_wait = cp->se_wait; #define SWAP(a, b) { char *c = a; a = b; b = c; } if (cp->se_user) SWAP(sep->se_user, cp->se_user); if (cp->se_server) SWAP(sep->se_server, cp->se_server); for (i = 0; i < MAXARGV; i++) SWAP(sep->se_argv[i], cp->se_argv[i]); sigsetmask(omask); freeconfig(cp); if (debug) print_service("REDO", sep); } else { sep = enter(cp); if (debug) print_service("ADD ", sep); } sep->se_checked = 1; if (ISMUX(sep)) { sep->se_fd = -1; continue; } if (!sep->se_rpc) { sp = getservbyname(sep->se_service, sep->se_proto); if (sp == 0) { syslog(LOG_ERR, "%s/%s: unknown service", sep->se_service, sep->se_proto); sep->se_checked = 0; continue; } if (sp->s_port != sep->se_ctrladdr.sin_port) { sep->se_ctrladdr.sin_family = AF_INET; sep->se_ctrladdr.sin_port = sp->s_port; if (sep->se_fd >= 0) close_sep(sep); } } else { rpc = getrpcbyname(sep->se_service); if (rpc == 0) { syslog(LOG_ERR, "%s/%s unknown RPC service.", sep->se_service, sep->se_proto); if (sep->se_fd != -1) (void) close(sep->se_fd); sep->se_fd = -1; continue; } if (rpc->r_number != sep->se_rpc_prog) { if (sep->se_rpc_prog) unregisterrpc(sep); sep->se_rpc_prog = rpc->r_number; if (sep->se_fd != -1) (void) close(sep->se_fd); sep->se_fd = -1; } } if (sep->se_fd == -1) setup(sep); } endconfig(); /* * Purge anything not looked at above. */ omask = sigblock(SIGBLOCK); sepp = &servtab; while (sep = *sepp) { if (sep->se_checked) { sepp = &sep->se_next; continue; } *sepp = sep->se_next; if (sep->se_fd >= 0) close_sep(sep); if (debug) print_service("FREE", sep); if (sep->se_rpc && sep->se_rpc_prog > 0) unregisterrpc(sep); freeconfig(sep); free((char *)sep); } (void) sigsetmask(omask); } void unregisterrpc(sep) struct servtab *sep; { int i; struct servtab *sepp; long omask; omask = sigblock(SIGBLOCK); for (sepp = servtab; sepp; sepp = sepp->se_next) { if (sepp == sep) continue; if (sep->se_checked == 0 || !sepp->se_rpc || sep->se_rpc_prog != sepp->se_rpc_prog) continue; return; } if (debug) print_service("UNREG", sep); for (i = sep->se_rpc_lowvers; i <= sep->se_rpc_highvers; i++) pmap_unset(sep->se_rpc_prog, i); if (sep->se_fd != -1) (void) close(sep->se_fd); sep->se_fd = -1; (void) sigsetmask(omask); } void retry(signo) int signo; { struct servtab *sep; timingout = 0; for (sep = servtab; sep; sep = sep->se_next) if (sep->se_fd == -1) setup(sep); } void setup(sep) struct servtab *sep; { int on = 1; if ((sep->se_fd = socket(AF_INET, sep->se_socktype, 0)) < 0) { if (debug) fprintf(stderr, "socket failed on %s/%s: %s\n", sep->se_service, sep->se_proto, strerror(errno)); syslog(LOG_ERR, "%s/%s: socket: %m", sep->se_service, sep->se_proto); return; } #define turnon(fd, opt) \ setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on)) if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) && turnon(sep->se_fd, SO_DEBUG) < 0) syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m"); if (turnon(sep->se_fd, SO_REUSEADDR) < 0) syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); if (turnon(sep->se_fd, SO_PRIVSTATE) < 0) syslog(LOG_ERR, "setsockopt (SO_PRIVSTATE): %m"); #undef turnon if (bind(sep->se_fd, (struct sockaddr *)&sep->se_ctrladdr, sizeof (sep->se_ctrladdr)) < 0) { if (debug) fprintf(stderr, "bind failed on %s/%s: %s\n", sep->se_service, sep->se_proto, strerror(errno)); syslog(LOG_ERR, "%s/%s: bind: %m", sep->se_service, sep->se_proto); (void) close(sep->se_fd); sep->se_fd = -1; if (!timingout) { timingout = 1; alarm(RETRYTIME); } return; } if (sep->se_rpc) { int i, len = sizeof(struct sockaddr); if (getsockname(sep->se_fd, (struct sockaddr*)&sep->se_ctrladdr, &len) < 0){ syslog(LOG_ERR, "%s/%s: getsockname: %m", sep->se_service, sep->se_proto); (void) close(sep->se_fd); sep->se_fd = -1; return; } if (debug) print_service("REG ", sep); for (i = sep->se_rpc_lowvers; i <= sep->se_rpc_highvers; i++) { pmap_unset(sep->se_rpc_prog, i); pmap_set(sep->se_rpc_prog, i, (sep->se_socktype == SOCK_DGRAM) ? IPPROTO_UDP : IPPROTO_TCP, ntohs(sep->se_ctrladdr.sin_port)); } } if (sep->se_socktype == SOCK_STREAM) listen(sep->se_fd, 64); FD_SET(sep->se_fd, &allsock); nsock++; if (sep->se_fd > maxsock) maxsock = sep->se_fd; if (debug) { fprintf(stderr, "registered %s on %d\n", sep->se_server, sep->se_fd); } } /* * Finish with a service and its socket. */ void close_sep(sep) struct servtab *sep; { if (sep->se_fd >= 0) { nsock--; FD_CLR(sep->se_fd, &allsock); (void) close(sep->se_fd); sep->se_fd = -1; } sep->se_count = 0; /* * Don't keep the pid of this running deamon: when reapchild() * reaps this pid, it would erroneously increment nsock. */ if (sep->se_wait > 1) sep->se_wait = 1; } struct servtab * enter(cp) struct servtab *cp; { struct servtab *sep; long omask; sep = (struct servtab *)malloc(sizeof (*sep)); if (sep == (struct servtab *)0) { syslog(LOG_ERR, "Out of memory."); exit(-1); } *sep = *cp; sep->se_fd = -1; omask = sigblock(SIGBLOCK); sep->se_next = servtab; servtab = sep; sigsetmask(omask); return (sep); } FILE *fconfig = NULL; struct servtab serv; char line[LINE_MAX]; int setconfig() { if (fconfig != NULL) { fseek(fconfig, 0L, SEEK_SET); return (1); } fconfig = fopen(CONFIG, "r"); return (fconfig != NULL); } void endconfig() { if (fconfig) { (void) fclose(fconfig); fconfig = NULL; } } struct servtab * getconfigent() { struct servtab *sep = &serv; int argc; char *cp, *arg; char *versp; static char TCPMUX_TOKEN[] = "tcpmux/"; #define MUX_LEN (sizeof(TCPMUX_TOKEN)-1) more: while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0')) ; if (cp == NULL) return ((struct servtab *)0); /* * clear the static buffer, since some fields (se_ctrladdr, * for example) don't get initialized here. */ memset((caddr_t)sep, 0, sizeof *sep); arg = skip(&cp); if (cp == NULL) { /* got an empty line containing just blanks/tabs. */ goto more; } if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) { char *c = arg + MUX_LEN; if (*c == '+') { sep->se_type = MUXPLUS_TYPE; c++; } else sep->se_type = MUX_TYPE; sep->se_service = newstr(c); } else { sep->se_service = newstr(arg); sep->se_type = NORM_TYPE; } arg = sskip(&cp); if (strcmp(arg, "stream") == 0) sep->se_socktype = SOCK_STREAM; else if (strcmp(arg, "dgram") == 0) sep->se_socktype = SOCK_DGRAM; else if (strcmp(arg, "rdm") == 0) sep->se_socktype = SOCK_RDM; else if (strcmp(arg, "seqpacket") == 0) sep->se_socktype = SOCK_SEQPACKET; else if (strcmp(arg, "raw") == 0) sep->se_socktype = SOCK_RAW; else sep->se_socktype = -1; sep->se_proto = newstr(sskip(&cp)); if (strncmp(sep->se_proto, "rpc/", 4) == 0) { sep->se_proto += 4; sep->se_rpc = 1; sep->se_rpc_prog = sep->se_rpc_lowvers = sep->se_rpc_lowvers = 0; sep->se_ctrladdr.sin_family = AF_INET; sep->se_ctrladdr.sin_port = 0; sep->se_ctrladdr.sin_addr = bind_address; if ((versp = rindex(sep->se_service, '/'))) { *versp++ = '\0'; switch (sscanf(versp, "%d-%d", &sep->se_rpc_lowvers, &sep->se_rpc_highvers)) { case 2: break; case 1: sep->se_rpc_highvers = sep->se_rpc_lowvers; break; default: syslog(LOG_ERR, "bad RPC version specifier; %s\n", sep->se_service); freeconfig(sep); goto more; } } else { sep->se_rpc_lowvers = sep->se_rpc_highvers = 1; } } arg = sskip(&cp); sep->se_wait = strcmp(arg, "wait") == 0; if (ISMUX(sep)) { /* * Silently enforce "nowait" for TCPMUX services since * they don't have an assigned port to listen on. */ sep->se_wait = 0; if (strcmp(sep->se_proto, "tcp")) { syslog(LOG_ERR, "%s: bad protocol for tcpmux service %s", CONFIG, sep->se_service); goto more; } if (sep->se_socktype != SOCK_STREAM) { syslog(LOG_ERR, "%s: bad socket type for tcpmux service %s", CONFIG, sep->se_service); goto more; } } sep->se_user = newstr(sskip(&cp)); sep->se_server = newstr(sskip(&cp)); if (strcmp(sep->se_server, "internal") == 0) { struct biltin *bi; for (bi = biltins; bi->bi_service; bi++) if (bi->bi_socktype == sep->se_socktype && strcmp(bi->bi_service, sep->se_service) == 0) break; if (bi->bi_service == 0) { syslog(LOG_ERR, "internal service %s unknown", sep->se_service); goto more; } sep->se_bi = bi; sep->se_wait = bi->bi_wait; } else sep->se_bi = NULL; argc = 0; for (arg = skip(&cp); cp; arg = skip(&cp)) if (argc < MAXARGV) sep->se_argv[argc++] = newstr(arg); while (argc <= MAXARGV) sep->se_argv[argc++] = NULL; return (sep); } void freeconfig(cp) struct servtab *cp; { int i; if (cp->se_service) free(cp->se_service); if (cp->se_proto) free(cp->se_proto); if (cp->se_user) free(cp->se_user); if (cp->se_server) free(cp->se_server); for (i = 0; i < MAXARGV; i++) if (cp->se_argv[i]) free(cp->se_argv[i]); } /* * Safe skip - if skip returns null, log a syntax error in the * configuration file and exit. */ char * sskip(cpp) char **cpp; { char *cp; cp = skip(cpp); if (cp == NULL) { syslog(LOG_ERR, "%s: syntax error", CONFIG); exit(-1); } return (cp); } char * skip(cpp) char **cpp; { char *cp = *cpp; char *start; char quote = '\0'; again: while (*cp == ' ' || *cp == '\t') cp++; if (*cp == '\0') { int c; c = getc(fconfig); (void) ungetc(c, fconfig); if (c == ' ' || c == '\t') if (cp = nextline(fconfig)) goto again; *cpp = (char *)0; return ((char *)0); } if (*cp == '"' || *cp == '\'') quote = *cp++; start = cp; if (quote) while (*cp && *cp != quote) cp++; else while (*cp && *cp != ' ' && *cp != '\t') cp++; if (*cp != '\0') *cp++ = '\0'; *cpp = cp; return (start); } char * nextline(fd) FILE *fd; { char *cp; if (fgets(line, sizeof (line), fd) == NULL) return ((char *)0); cp = strchr(line, '\n'); if (cp) *cp = '\0'; return (line); } char * newstr(cp) char *cp; { if (cp = strdup(cp ? cp : "")) return (cp); syslog(LOG_ERR, "strdup: %m"); exit(-1); } #ifdef OLD_SETPROCTITLE void inetd_setproctitle(a, s) char *a; int s; { int size; char *cp; struct sockaddr_in sin; char buf[80]; cp = Argv[0]; size = sizeof(sin); if (getpeername(s, (struct sockaddr *)&sin, &size) == 0) (void) sprintf(buf, "-%s [%s]", a, inet_ntoa(sin.sin_addr)); else (void) sprintf(buf, "-%s", a); strncpy(cp, buf, LastArg - cp); cp += strlen(cp); while (cp < LastArg) *cp++ = ' '; } #else void inetd_setproctitle(a, s) char *a; int s; { int size; struct sockaddr_in sin; char buf[80]; size = sizeof(sin); if (getpeername(s, (struct sockaddr *)&sin, &size) == 0) (void) sprintf(buf, "%s [%s]", a, inet_ntoa(sin.sin_addr)); else (void) sprintf(buf, "%s", a); setproctitle("%s", buf); } #endif /* * Internet services provided internally by inetd: */ #define BUFSIZE 8192 /* ARGSUSED */ void echo_stream(s, sep) /* Echo service -- echo data back */ int s; struct servtab *sep; { char buffer[BUFSIZE]; int i; inetd_setproctitle(sep->se_service, s); while ((i = read(s, buffer, sizeof(buffer))) > 0 && write(s, buffer, i) > 0) ; exit(0); } int check_loop(sin, sep) struct sockaddr_in *sin; struct servtab *sep; { struct servtab *se2; for (se2 = servtab; se2; se2 = se2->se_next) { if (!se2->se_bi || se2->se_socktype != SOCK_DGRAM) continue; if (sin->sin_port == se2->se_ctrladdr.sin_port) { syslog(LOG_WARNING, "%s/%s:%s/%s loop request REFUSED from %s", sep->se_service, sep->se_proto, se2->se_service, se2->se_proto, inet_ntoa(sin->sin_addr)); return 1; } } return 0; } /* ARGSUSED */ void echo_dg(s, sep) /* Echo service -- echo data back */ int s; struct servtab *sep; { char buffer[BUFSIZE]; int i, size; struct sockaddr_in sin; size = sizeof(sin); if ((i = recvfrom(s, buffer, sizeof(buffer), 0, (struct sockaddr *)&sin, &size)) < 0) return; if (check_loop(&sin, sep)) return; (void) sendto(s, buffer, i, 0, (struct sockaddr *)&sin, sizeof(sin)); } /* ARGSUSED */ void discard_stream(s, sep) /* Discard service -- ignore data */ int s; struct servtab *sep; { int ret; char buffer[BUFSIZE]; inetd_setproctitle(sep->se_service, s); while (1) { while ((ret = read(s, buffer, sizeof(buffer))) > 0) ; if (ret == 0 || errno != EINTR) break; } exit(0); } /* ARGSUSED */ void discard_dg(s, sep) /* Discard service -- ignore data */ int s; struct servtab *sep; { char buffer[BUFSIZE]; (void) read(s, buffer, sizeof(buffer)); } #include #define LINESIZ 72 char ring[128]; char *endring; void initring() { int i; endring = ring; for (i = 0; i <= 128; ++i) if (isprint(i)) *endring++ = i; } /* ARGSUSED */ void chargen_stream(s, sep) /* Character generator */ int s; struct servtab *sep; { int len; char *rs, text[LINESIZ+2]; inetd_setproctitle(sep->se_service, s); if (!endring) { initring(); rs = ring; } text[LINESIZ] = '\r'; text[LINESIZ + 1] = '\n'; for (rs = ring;;) { if ((len = endring - rs) >= LINESIZ) memmove(text, rs, LINESIZ); else { memmove(text, rs, len); memmove(text + len, ring, LINESIZ - len); } if (++rs == endring) rs = ring; if (write(s, text, sizeof(text)) != sizeof(text)) break; } exit(0); } /* ARGSUSED */ void chargen_dg(s, sep) /* Character generator */ int s; struct servtab *sep; { struct sockaddr_in sin; static char *rs; int len, size; char text[LINESIZ+2]; if (endring == 0) { initring(); rs = ring; } size = sizeof(sin); if (recvfrom(s, text, sizeof(text), 0, (struct sockaddr *)&sin, &size) < 0) return; if (check_loop(&sin, sep)) return; if ((len = endring - rs) >= LINESIZ) memmove(text, rs, LINESIZ); else { memmove(text, rs, len); memmove(text + len, ring, LINESIZ - len); } if (++rs == endring) rs = ring; text[LINESIZ] = '\r'; text[LINESIZ + 1] = '\n'; (void) sendto(s, text, sizeof(text), 0, (struct sockaddr *)&sin, sizeof(sin)); } /* * Return a machine readable date and time, in the form of the * number of seconds since midnight, Jan 1, 1900. Since gettimeofday * returns the number of seconds since midnight, Jan 1, 1970, * we must add 2208988800 seconds to this figure to make up for * some seventy years Bell Labs was asleep. */ long machtime() { struct timeval tv; if (gettimeofday(&tv, (struct timezone *)0) < 0) { if (debug) fprintf(stderr, "Unable to get time of day\n"); return (0L); } #define OFFSET ((u_long)25567 * 24*60*60) return (htonl((long)(tv.tv_sec + OFFSET))); #undef OFFSET } /* ARGSUSED */ void machtime_stream(s, sep) int s; struct servtab *sep; { long result; result = machtime(); (void) write(s, (char *) &result, sizeof(result)); } /* ARGSUSED */ void machtime_dg(s, sep) int s; struct servtab *sep; { long result; struct sockaddr_in sin; int size; size = sizeof(sin); if (recvfrom(s, (char *)&result, sizeof(result), 0, (struct sockaddr *)&sin, &size) < 0) return; if (check_loop(&sin, sep)) return; result = machtime(); (void) sendto(s, (char *) &result, sizeof(result), 0, (struct sockaddr *)&sin, sizeof(sin)); } /* ARGSUSED */ void daytime_stream(s, sep) /* Return human-readable time of day */ int s; struct servtab *sep; { char buffer[256]; time_t clock; clock = time((time_t *) 0); (void) sprintf(buffer, "%.24s\r\n", ctime(&clock)); (void) write(s, buffer, strlen(buffer)); } /* ARGSUSED */ void daytime_dg(s, sep) /* Return human-readable time of day */ int s; struct servtab *sep; { char buffer[256]; time_t clock; struct sockaddr_in sin; int size; clock = time((time_t *) 0); size = sizeof(sin); if (recvfrom(s, buffer, sizeof(buffer), 0, (struct sockaddr *)&sin, &size) < 0) return; if (check_loop(&sin, sep)) return; (void) sprintf(buffer, "%.24s\r\n", ctime(&clock)); (void) sendto(s, buffer, strlen(buffer), 0, (struct sockaddr *)&sin, sizeof(sin)); } /* * print_service: * Dump relevant information to stderr */ void print_service(action, sep) char *action; struct servtab *sep; { if(sep->se_rpc) fprintf(stderr, "%s: %s proto=%s, wait=%d, user=%s builtin=%x server=%s\n", action, sep->se_service, sep->se_proto, sep->se_wait, sep->se_user, (int)sep->se_bi, sep->se_server); else fprintf(stderr, "%s: %s proto=%s, wait=%d, user=%s builtin=%x server=%s\n", action, sep->se_service, sep->se_proto, sep->se_wait, sep->se_user, (int)sep->se_bi, sep->se_server); } /* * Based on TCPMUX.C by Mark K. Lottor November 1988 * sri-nic::ps:tcpmux.c */ static int /* # of characters upto \r,\n or \0 */ getline(fd, buf, len) int fd; char *buf; int len; { int count = 0, n; do { n = read(fd, buf, len-count); if (n == 0) return (count); if (n < 0) return (-1); while (--n >= 0) { if (*buf == '\r' || *buf == '\n' || *buf == '\0') return (count); count++; buf++; } } while (count < len); return (count); } #define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ #define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) struct servtab * tcpmux(s) int s; { struct servtab *sep; char service[MAX_SERV_LEN+1]; int len; /* Get requested service name */ if ((len = getline(s, service, MAX_SERV_LEN)) < 0) { strwrite(s, "-Error reading service name\r\n"); return (NULL); } service[len] = '\0'; if (debug) fprintf(stderr, "tcpmux: someone wants %s\n", service); /* * Help is a required command, and lists available services, * one per line. */ if (!strcasecmp(service, "help")) { for (sep = servtab; sep; sep = sep->se_next) { if (!ISMUX(sep)) continue; (void)write(s,sep->se_service,strlen(sep->se_service)); strwrite(s, "\r\n"); } return (NULL); } /* Try matching a service in inetd.conf with the request */ for (sep = servtab; sep; sep = sep->se_next) { if (!ISMUX(sep)) continue; if (!strcasecmp(service, sep->se_service)) { if (ISMUXPLUS(sep)) { strwrite(s, "+Go\r\n"); } return (sep); } } strwrite(s, "-Service not available\r\n"); return (NULL); }