/* $NetBSD: inetd.c,v 1.142 2025/12/27 08:06:38 mlelstv Exp $ */ /*- * Copyright (c) 1998, 2003 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, * NASA Ames Research Center and by Matthias Scheler. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ /* * 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. 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. */ #include #ifndef lint __COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\ The Regents of the University of California. All rights reserved."); #if 0 static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94"; #else __RCSID("$NetBSD: inetd.c,v 1.142 2025/12/27 08:06:38 mlelstv Exp $"); #endif #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[:accf[,arg]] stream/dgram/raw/rdm/seqpacket, only stream can name an accept filter * protocol must be in /etc/protocols * wait/nowait[:max] single-threaded/multi-threaded, max # * user[:group] user/group to run daemon as * server program full path name * server program arguments maximum of MAXARGV (64) * * 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[:max] single-threaded/multi-threaded * user[:group] user to run daemon as * server program full path name * server program arguments maximum of MAXARGV (64) * * For non-RPC services, the "service name" can be of the form * hostaddress:servicename, in which case the hostaddress is used * as the host portion of the address to listen on. If hostaddress * consists of a single `*' character, INADDR_ANY is used. * * A line can also consist of just * hostaddress: * where hostaddress is as in the preceding paragraph. Such a line must * have no further fields; the specified hostaddress is remembered and * used for all further lines that have no hostaddress specified, * until the next such line (or EOF). (This is why * is provided to * allow explicit specification of INADDR_ANY.) A line * *: * is implicitly in effect at the beginning of the file. * * The hostaddress specifier may (and often will) contain dots; * the service name must not. * * For RPC services, host-address specifiers are accepted and will * work to some extent; however, because of limitations in the * portmapper interface, it will not work to try to give more than * one line for any given RPC service, even if the host-address * specifiers are different. * * 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. * * Comment lines are indicated by a `#' in column 1. * * #ifdef IPSEC * Comment lines that start with "#@" denote IPsec policy string, as described * in ipsec_set_policy(3). This will affect all the following items in * inetd.conf(8). To reset the policy, just use "#@" line. By default, * there's no IPsec policy. * #endif */ /* * Here's the scoop concerning the user:group feature: * * 1) set-group-option off. * * a) user = root: NO setuid() or setgid() is done * * b) other: setuid() * setgid(primary group as found in passwd) * initgroups(name, primary group) * * 2) set-group-option on. * * a) user = root: NO setuid() * setgid(specified group) * NO initgroups() * * b) other: setuid() * setgid(specified group) * initgroups(name, specified group) * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "inetd.h" #ifdef LIBWRAP # include #ifndef LIBWRAP_ALLOW_FACILITY # define LIBWRAP_ALLOW_FACILITY LOG_AUTH #endif #ifndef LIBWRAP_ALLOW_SEVERITY # define LIBWRAP_ALLOW_SEVERITY LOG_INFO #endif #ifndef LIBWRAP_DENY_FACILITY # define LIBWRAP_DENY_FACILITY LOG_AUTH #endif #ifndef LIBWRAP_DENY_SEVERITY # define LIBWRAP_DENY_SEVERITY LOG_WARNING #endif int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY; int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY; #endif static bool foreground; int debug; #ifdef LIBWRAP int lflag; #endif int maxsock; int kq; int options; int timingout; const int niflags = NI_NUMERICHOST | NI_NUMERICSERV; #ifndef OPEN_MAX #define OPEN_MAX 64 #endif /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */ #define FD_MARGIN (8) rlim_t rlim_ofile_cur = OPEN_MAX; struct rlimit rlim_ofile; struct kevent changebuf[64]; size_t changes; struct servtab *servtab; static ssize_t recvfromto(int, void * restrict, size_t, int, struct sockaddr * restrict, socklen_t * restrict, struct sockaddr * restrict, socklen_t * restrict); static ssize_t sendfromto(int, const void *, size_t, int, const struct sockaddr *, socklen_t, const struct sockaddr *, socklen_t); static void chargen_dg(int, struct servtab *); static void chargen_stream(int, struct servtab *); static void daytime_dg(int, struct servtab *); static void daytime_stream(int, struct servtab *); static void discard_dg(int, struct servtab *); static void discard_stream(int, struct servtab *); static void echo_dg(int, struct servtab *); static void echo_stream(int, struct servtab *); __dead static void goaway(void); static void machtime_dg(int, struct servtab *); static void machtime_stream(int, struct servtab *); static void reapchild(void); static void retry(void); static void run_service(int, struct servtab *, int); static void tcpmux(int, struct servtab *); __dead static void usage(void); static void bump_nofile(void); static void inetd_setproctitle(char *, int); static void initring(void); static uint32_t machtime(void); static int port_good_dg(struct sockaddr *); static int dg_broadcast(struct in_addr *); static int my_kevent(const struct kevent *, size_t, struct kevent *, size_t); static struct kevent *allocchange(void); static int get_line(int, char *, int); static void spawn(struct servtab *, int); static void suspend_sep(struct servtab *); static void resume_sep(struct servtab *); static void add_child(struct servtab *, pid_t); static void remove_child(struct servtab *, pid_t); struct biltin { const 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)(int, struct servtab *); /* function which performs it */ } biltins[] = { /* Echo received data */ { "echo", SOCK_STREAM, true, false, echo_stream }, { "echo", SOCK_DGRAM, false, false, echo_dg }, /* Internet /dev/null */ { "discard", SOCK_STREAM, true, false, discard_stream }, { "discard", SOCK_DGRAM, false, false, discard_dg }, /* Return 32 bit time since 1970 */ { "time", SOCK_STREAM, false, false, machtime_stream }, { "time", SOCK_DGRAM, false, false, machtime_dg }, /* Return human-readable time */ { "daytime", SOCK_STREAM, false, false, daytime_stream }, { "daytime", SOCK_DGRAM, false, false, daytime_dg }, /* Familiar character generator */ { "chargen", SOCK_STREAM, true, false, chargen_stream }, { "chargen", SOCK_DGRAM, false, false, chargen_dg }, { "tcpmux", SOCK_STREAM, true, false, tcpmux } }; /* list of "bad" ports. I.e. ports that are most obviously used for * "cycling packets" denial of service attacks. See /etc/services. * List must end with port number "0". */ u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0 }; #define NUMINT (sizeof(intab) / sizeof(struct inent)) const char *CONFIG = _PATH_INETDCONF; static int my_signals[] = { SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE }; int main(int argc, char *argv[]) { int ch, n, reload = 1; while ((ch = getopt(argc, argv, #ifdef LIBWRAP "dfl" #else "df" #endif )) != -1) switch(ch) { case 'd': foreground = true; debug = true; options |= SO_DEBUG; break; case 'f': foreground = true; break; #ifdef LIBWRAP case 'l': lflag = true; break; #endif case '?': default: usage(); } argc -= optind; argv += optind; if (argc > 0) CONFIG = argv[0]; if (!foreground) daemon(0, 0); openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON); pidfile(NULL); kq = kqueue(); if (kq < 0) { syslog(LOG_ERR, "kqueue: %m"); return (EXIT_FAILURE); } if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) { syslog(LOG_ERR, "getrlimit: %m"); } else { rlim_ofile_cur = rlim_ofile.rlim_cur; if (rlim_ofile_cur == RLIM_INFINITY) /* ! */ rlim_ofile_cur = OPEN_MAX; } for (n = 0; n < (int)__arraycount(my_signals); n++) { int signum; signum = my_signals[n]; if (signum != SIGCHLD) (void) signal(signum, SIG_IGN); if (signum != SIGPIPE) { struct kevent *ev; ev = allocchange(); EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE, 0, 0, 0); } } for (;;) { int ctrl; struct kevent eventbuf[64], *ev; struct servtab *sep; if (reload) { reload = false; config_root(); } n = my_kevent(changebuf, changes, eventbuf, __arraycount(eventbuf)); changes = 0; for (ev = eventbuf; n > 0; ev++, n--) { if (ev->filter == EVFILT_SIGNAL) { switch (ev->ident) { case SIGALRM: retry(); break; case SIGCHLD: reapchild(); break; case SIGTERM: case SIGINT: goaway(); break; case SIGHUP: reload = true; break; } continue; } if (ev->filter != EVFILT_READ) continue; sep = (struct servtab *)ev->udata; /* Paranoia */ if ((int)ev->ident != sep->se_fd) continue; DPRINTF(SERV_FMT ": service requested" , SERV_PARAMS(sep)); if (sep->se_wait == 0 && sep->se_socktype == SOCK_STREAM) { /* XXX here do the libwrap check-before-accept*/ ctrl = accept(sep->se_fd, NULL, NULL); DPRINTF(SERV_FMT ": accept, ctrl fd %d", SERV_PARAMS(sep), ctrl); if (ctrl < 0) { if (errno != EINTR && errno != EBADF) syslog(LOG_WARNING, SERV_FMT ": accept: %m", SERV_PARAMS(sep)); continue; } sep->se_accept_count++; if (sep->se_accept_max != SERVTAB_UNSPEC_SIZE_T && sep->se_accept_count >= sep->se_accept_max) suspend_sep(sep); } else ctrl = sep->se_fd; spawn(sep, ctrl); } } } static void spawn(struct servtab *sep, int ctrl) { int dofork; pid_t pid; pid = 0; #ifdef LIBWRAP_INTERNAL dofork = true; #else dofork = (sep->se_bi == NULL || sep->se_bi->bi_fork); #endif if (dofork) { if (rl_process(sep, ctrl)) { return; } pid = fork(); if (pid < 0) { syslog(LOG_ERR, "fork: %m"); if (sep->se_wait == 0 && sep->se_socktype == SOCK_STREAM) { sep->se_accept_count--; if (sep->se_accept_max != SERVTAB_UNSPEC_SIZE_T && sep->se_accept_count < sep->se_accept_max) resume_sep(sep); close(ctrl); } sleep(1); return; } if (pid != 0 && sep->se_accept_children != NULL) add_child(sep, pid); if (pid != 0 && sep->se_wait != 0) { struct kevent *ev; sep->se_wait = pid; ev = allocchange(); EV_SET(ev, sep->se_fd, EVFILT_READ, EV_DELETE, 0, 0, 0); } if (pid == 0) { size_t n; for (n = 0; n < __arraycount(my_signals); n++) (void) signal(my_signals[n], SIG_DFL); /* Don't put services in terminal session */ if (foreground) setsid(); } } if (pid == 0) { run_service(ctrl, sep, dofork); if (dofork) exit(EXIT_SUCCESS); } if (sep->se_wait == 0 && sep->se_socktype == SOCK_STREAM) close(ctrl); } static void run_service(int ctrl, struct servtab *sep, int didfork) { struct passwd *pwd; struct group *grp = NULL; /* XXX gcc */ char buf[NI_MAXSERV]; struct servtab *s; #ifdef LIBWRAP char abuf[BUFSIZ]; struct request_info req; int denied; char *service = NULL; /* XXX gcc */ #endif #ifdef LIBWRAP #ifndef LIBWRAP_INTERNAL if (sep->se_bi == 0) #endif if (sep->se_wait == 0 && sep->se_socktype == SOCK_STREAM) { request_init(&req, RQ_DAEMON, sep->se_argv[0] != NULL ? sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL); fromhost(&req); denied = hosts_access(&req) == 0; if (denied || lflag) { if (getnameinfo(&sep->se_ctrladdr, (socklen_t)sep->se_ctrladdr.sa_len, NULL, 0, buf, sizeof(buf), 0) != 0) { /* shouldn't happen */ (void)snprintf(buf, sizeof buf, "%d", ntohs(sep->se_ctrladdr_in.sin_port)); } service = buf; if (req.client->sin != NULL) { sockaddr_snprintf(abuf, sizeof(abuf), "%a", req.client->sin); } else { strcpy(abuf, "(null)"); } } if (denied) { syslog(deny_severity, "refused connection from %.500s(%s), service %s (%s)", eval_client(&req), abuf, service, sep->se_proto); goto reject; } if (lflag) { syslog(allow_severity, "connection from %.500s(%s), service %s (%s)", eval_client(&req), abuf, service, sep->se_proto); } } #endif /* LIBWRAP */ if (sep->se_bi != NULL) { if (didfork) { for (s = servtab; s != NULL; s = s->se_next) if (s->se_fd != -1 && s->se_fd != ctrl) { close(s->se_fd); s->se_fd = -1; } } (*sep->se_bi->bi_fn)(ctrl, sep); } else { 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); goto reject; } if (sep->se_group != NULL && (grp = getgrnam(sep->se_group)) == NULL) { syslog(LOG_ERR, "%s/%s: %s: No such group", sep->se_service, sep->se_proto, sep->se_group); goto reject; } if (pwd->pw_uid != 0) { if (sep->se_group != NULL) pwd->pw_gid = grp->gr_gid; if (setgid(pwd->pw_gid) < 0) { syslog(LOG_ERR, "%s/%s: can't set gid %d: %m", sep->se_service, sep->se_proto, pwd->pw_gid); goto reject; } (void) initgroups(pwd->pw_name, pwd->pw_gid); if (setuid(pwd->pw_uid) < 0) { syslog(LOG_ERR, "%s/%s: can't set uid %d: %m", sep->se_service, sep->se_proto, pwd->pw_uid); goto reject; } } else if (sep->se_group != NULL) { (void) setgid((gid_t)grp->gr_gid); } DPRINTF("%d execl %s", getpid(), sep->se_server); /* Set our control descriptor to not close-on-exec... */ if (fcntl(ctrl, F_SETFD, 0) < 0) syslog(LOG_ERR, "fcntl (%d, F_SETFD, 0): %m", ctrl); /* ...and dup it to stdin, stdout, and stderr. */ if (ctrl != 0) { dup2(ctrl, 0); close(ctrl); ctrl = 0; } dup2(0, 1); dup2(0, 2); if (rlim_ofile.rlim_cur != rlim_ofile_cur && setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) syslog(LOG_ERR, "setrlimit: %m"); execv(sep->se_server, sep->se_argv); syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server); reject: if (sep->se_socktype != SOCK_STREAM) recv(ctrl, buf, sizeof (buf), 0); _exit(EXIT_FAILURE); } } static void add_child(struct servtab *sep, pid_t pid) { if (sep->se_accept_max != SERVTAB_UNSPEC_SIZE_T && sep->se_accept_count <= sep->se_accept_max && sep->se_accept_count > 0) sep->se_accept_children[sep->se_accept_count-1] = pid; } static void remove_child(struct servtab *sep, pid_t pid) { size_t i, tail; for (i=0; ise_accept_count; ++i) { if (sep->se_accept_children[i] != pid) continue; if (sep->se_accept_max != SERVTAB_UNSPEC_SIZE_T && sep->se_accept_count <= sep->se_accept_max) resume_sep(sep); sep->se_accept_count--; tail = sep->se_accept_count - i; memmove(&sep->se_accept_children[i], &sep->se_accept_children[i+1], tail * sizeof(pid_t)); break; } } static void reapchild(void) { int status; pid_t pid; struct servtab *sep; for (;;) { pid = wait3(&status, WNOHANG, NULL); if (pid <= 0) break; DPRINTF("%d reaped, status %#x", pid, status); for (sep = servtab; sep != NULL; sep = sep->se_next) { if (sep->se_wait == pid) { struct kevent *ev; if (WIFEXITED(status) && WEXITSTATUS(status)) syslog(LOG_WARNING, "%s: exit status %u", sep->se_server, WEXITSTATUS(status)); else if (WIFSIGNALED(status)) syslog(LOG_WARNING, "%s: exit signal %u", sep->se_server, WTERMSIG(status)); sep->se_wait = 1; ev = allocchange(); EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep); DPRINTF("restored %s, fd %d", sep->se_service, sep->se_fd); } if (sep->se_accept_children != NULL) remove_child(sep, pid); } } } static void retry(void) { struct servtab *sep; timingout = false; for (sep = servtab; sep != NULL; sep = sep->se_next) { if (sep->se_fd == -1 && !ISMUX(sep)) { switch (sep->se_family) { case AF_LOCAL: case AF_INET: #ifdef INET6 case AF_INET6: #endif setup(sep); if (sep->se_fd >= 0 && isrpcservice(sep)) register_rpc(sep); break; } } } } static void goaway(void) { struct servtab *sep; for (sep = servtab; sep != NULL; sep = sep->se_next) { if (sep->se_fd == -1) continue; switch (sep->se_family) { case AF_LOCAL: (void)unlink(sep->se_service); break; case AF_INET: #ifdef INET6 case AF_INET6: #endif if (sep->se_wait == 1 && isrpcservice(sep)) unregister_rpc(sep); break; } (void)close(sep->se_fd); sep->se_fd = -1; } DPRINTF("Going away."); exit(EXIT_SUCCESS); } void setup(struct servtab *sep) { int on = 1; #ifdef INET6 int off = 0; #endif struct kevent *ev; if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { DPRINTF("socket failed on " SERV_FMT ": %s", SERV_PARAMS(sep), strerror(errno)); syslog(LOG_ERR, "%s/%s: socket: %m", sep->se_service, sep->se_proto); return; } /* Set all listening sockets to close-on-exec. */ if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) { syslog(LOG_ERR, SERV_FMT ": fcntl(F_SETFD, FD_CLOEXEC): %m", SERV_PARAMS(sep)); close(sep->se_fd); sep->se_fd = -1; return; } #define turnon(fd, opt) \ setsockopt(fd, SOL_SOCKET, opt, &on, (socklen_t)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"); #undef turnon /* Set the socket buffer sizes, if specified. */ if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, SO_SNDBUF, &sep->se_sndbuf, (socklen_t)sizeof(sep->se_sndbuf)) < 0) syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m", sep->se_sndbuf); if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET, SO_RCVBUF, &sep->se_rcvbuf, (socklen_t)sizeof(sep->se_rcvbuf)) < 0) syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m", sep->se_rcvbuf); #ifdef INET6 if (sep->se_family == AF_INET6) { int *v; v = (sep->se_type == FAITH_TYPE) ? &on : &off; if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_FAITH, v, (socklen_t)sizeof(*v)) < 0) syslog(LOG_ERR, "setsockopt (IPV6_FAITH): %m"); } #endif #ifdef IPSEC /* Avoid setting a policy if a policy specifier doesn't exist. */ if (sep->se_policy != NULL) { int e = ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy); if (e < 0) { syslog(LOG_ERR, SERV_FMT ": ipsec setup failed", SERV_PARAMS(sep)); (void)close(sep->se_fd); sep->se_fd = -1; return; } } #endif if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { DPRINTF(SERV_FMT ": bind failed: %s", SERV_PARAMS(sep), strerror(errno)); syslog(LOG_ERR, SERV_FMT ": bind: %m", SERV_PARAMS(sep)); (void) close(sep->se_fd); sep->se_fd = -1; if (!timingout) { timingout = true; alarm(RETRYTIME); } return; } if (sep->se_socktype == SOCK_STREAM) listen(sep->se_fd, 128); /* for internal dgram, setsockopt() is required for recvfromto() */ if (sep->se_socktype == SOCK_DGRAM && sep->se_bi != NULL) { switch (sep->se_family) { case AF_INET: if (setsockopt(sep->se_fd, IPPROTO_IP, IP_RECVDSTADDR, &on, sizeof(on)) < 0) syslog(LOG_ERR, "setsockopt (IP_RECVDSTADDR): %m"); break; #ifdef INET6 case AF_INET6: if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, sizeof(on)) < 0) syslog(LOG_ERR, "setsockopt (IPV6_RECVPKTINFO): %m"); break; #endif } } /* Allocate list of children */ if (sep->se_accept_max != SERVTAB_UNSPEC_SIZE_T && sep->se_accept_max > 0) { sep->se_accept_children = calloc(sep->se_accept_max, sizeof(pid_t)); if (sep->se_accept_children == NULL) { syslog(LOG_ERR, SERV_FMT ": accept_max too large: %m", SERV_PARAMS(sep)); sep->se_accept_max = SERVTAB_UNSPEC_SIZE_T; } } /* Set the accept filter, if specified. To be done after listen.*/ if (sep->se_accf.af_name[0] != 0 && setsockopt(sep->se_fd, SOL_SOCKET, SO_ACCEPTFILTER, &sep->se_accf, (socklen_t)sizeof(sep->se_accf)) < 0) syslog(LOG_ERR, "setsockopt(SO_ACCEPTFILTER %s): %m", sep->se_accf.af_name); ev = allocchange(); EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep); if (sep->se_fd > maxsock) { maxsock = sep->se_fd; if (maxsock > (int)(rlim_ofile_cur - FD_MARGIN)) bump_nofile(); } DPRINTF(SERV_FMT ": registered on fd %d", SERV_PARAMS(sep), sep->se_fd); } /* * Finish with a service and its socket. */ void close_sep(struct servtab *sep) { if (sep->se_fd >= 0) { (void) close(sep->se_fd); sep->se_fd = -1; } sep->se_count = 0; if (sep->se_ip_max != SERVTAB_UNSPEC_SIZE_T) { rl_clear_ip_list(sep); } } /* * Suspend service by ignoring connect events */ static void suspend_sep(struct servtab *sep) { struct kevent *ev; if (sep->se_accept_count == sep->se_accept_max) { ev = allocchange(); EV_SET(ev, sep->se_fd, EVFILT_READ, EV_DISABLE, 0, 0, (intptr_t)sep); } if (sep->se_accept_mark == 0) syslog(LOG_ERR, SERV_FMT ": accept_max reached (%zu);" "service suspended", SERV_PARAMS(sep), sep->se_accept_max); if (sep->se_accept_max > 0) sep->se_accept_mark = sep->se_accept_max - 1; else sep->se_accept_mark = 0; } /* * Resume service by listening to connect events */ static void resume_sep(struct servtab *sep) { struct kevent *ev; if (sep->se_accept_count == sep->se_accept_max) { ev = allocchange(); EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ENABLE, 0, 0, (intptr_t)sep); } if (sep->se_accept_mark == 0 || sep->se_accept_count < sep->se_accept_mark) { syslog(LOG_ERR, SERV_FMT ": fell below accept_max (%zu);" "service resumed", SERV_PARAMS(sep), sep->se_accept_max); sep->se_accept_mark = 0; } } void register_rpc(struct servtab *sep) { #ifdef RPC struct netbuf nbuf; struct sockaddr_storage ss; struct netconfig *nconf; socklen_t socklen; int n; if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { syslog(LOG_ERR, "%s: getnetconfigent failed", sep->se_proto); return; } socklen = sizeof ss; if (getsockname(sep->se_fd, (struct sockaddr *)(void *)&ss, &socklen) < 0) { syslog(LOG_ERR, SERV_FMT ": getsockname: %m", SERV_PARAMS(sep)); return; } nbuf.buf = &ss; nbuf.len = ss.ss_len; nbuf.maxlen = sizeof (struct sockaddr_storage); for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { DPRINTF("rpcb_set: %u %d %s %s", sep->se_rpcprog, n, nconf->nc_netid, taddr2uaddr(nconf, &nbuf)); (void)rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf); if (rpcb_set((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf, &nbuf) == 0) syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s", sep->se_rpcprog, n, nconf->nc_netid, taddr2uaddr(nconf, &nbuf), clnt_spcreateerror("")); } #endif /* RPC */ } void unregister_rpc(struct servtab *sep) { #ifdef RPC int n; struct netconfig *nconf; if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) { syslog(LOG_ERR, "%s: getnetconfigent failed", sep->se_proto); return; } for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) { DPRINTF("rpcb_unset(%u, %d, %s)", sep->se_rpcprog, n, nconf->nc_netid); if (rpcb_unset((unsigned int)sep->se_rpcprog, (unsigned int)n, nconf) == 0) syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n", sep->se_rpcprog, n, nconf->nc_netid); } #endif /* RPC */ } static void inetd_setproctitle(char *a, int s) { socklen_t size; struct sockaddr_storage ss; char hbuf[NI_MAXHOST]; const char *hp; struct sockaddr *sa; size = sizeof(ss); sa = (struct sockaddr *)(void *)&ss; if (getpeername(s, sa, &size) == 0) { if (getnameinfo(sa, size, hbuf, (socklen_t)sizeof(hbuf), NULL, 0, niflags) != 0) hp = "?"; else hp = hbuf; setproctitle("-%s [%s]", a, hp); } else setproctitle("-%s", a); } static void bump_nofile(void) { #define FD_CHUNK 32 struct rlimit rl; if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { syslog(LOG_ERR, "getrlimit: %m"); return; } rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); if (rl.rlim_cur <= rlim_ofile_cur) { syslog(LOG_ERR, "bump_nofile: cannot extend file limit, max = %d", (int)rl.rlim_cur); return; } if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { syslog(LOG_ERR, "setrlimit: %m"); return; } rlim_ofile_cur = rl.rlim_cur; return; } /* * In order to get the destination address (`to') with recvfromto(), * IP_RECVDSTADDR or IP_RECVPKTINFO for AF_INET, or IPV6_RECVPKTINFO * for AF_INET6, must be enabled with setsockopt(2). * * .sin_port and .sin6_port in 'to' are always stored as zero. * If necessary, extract them using getsockname(2). */ static ssize_t recvfromto(int s, void * restrict buf, size_t len, int flags, struct sockaddr * restrict from, socklen_t * restrict fromlen, struct sockaddr * restrict to, socklen_t * restrict tolen) { struct msghdr msg; struct iovec vec; struct cmsghdr *cmsg; struct sockaddr_storage ss; char cmsgbuf[1024]; ssize_t rc; if (to == NULL) return recvfrom(s, buf, len, flags, from, fromlen); if (tolen == NULL || fromlen == NULL) { errno = EFAULT; return -1; } vec.iov_base = buf; vec.iov_len = len; msg.msg_name = from; msg.msg_namelen = *fromlen; msg.msg_iov = &vec; msg.msg_iovlen = 1; msg.msg_control = cmsgbuf; msg.msg_controllen = sizeof(cmsgbuf); rc = recvmsg(s, &msg, flags); if (rc < 0) return rc; *fromlen = msg.msg_namelen; memset(&ss, 0, sizeof(ss)); for (cmsg = (struct cmsghdr *)CMSG_FIRSTHDR(&msg); cmsg != NULL; cmsg = (struct cmsghdr *)CMSG_NXTHDR(&msg, cmsg)) { if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_RECVDSTADDR) { struct in_addr *dst = (struct in_addr *)CMSG_DATA(cmsg); struct sockaddr_in *sin = (struct sockaddr_in *)&ss; sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; sin->sin_addr = *dst; break; } if (cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_PKTINFO) { struct in_pktinfo *pi = (struct in_pktinfo *)CMSG_DATA(cmsg); struct sockaddr_in *sin = (struct sockaddr_in *)&ss; sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; sin->sin_addr = pi->ipi_addr; break; } #ifdef INET6 if (cmsg->cmsg_level == IPPROTO_IPV6 && cmsg->cmsg_type == IPV6_PKTINFO) { struct in6_pktinfo *pi6 = (struct in6_pktinfo *)CMSG_DATA(cmsg); struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&ss; sin6->sin6_len = sizeof(*sin6); sin6->sin6_family = AF_INET6; sin6->sin6_addr = pi6->ipi6_addr; if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) || IN6_IS_ADDR_MC_LINKLOCAL(&sin6->sin6_addr)) sin6->sin6_scope_id = pi6->ipi6_ifindex; else sin6->sin6_scope_id = 0; break; } #endif /* INET6 */ } socklen_t sslen = (*tolen < ss.ss_len) ? *tolen : ss.ss_len; if (sslen > 0) memcpy(to, &ss, sslen); *tolen = sslen; return rc; } /* * When sending, the source port is selected as the one bind(2)'ed * to the socket. * .sin_port and .sin6_port in `from' are always ignored. */ static ssize_t sendfromto(int s, const void *buf, size_t len, int flags, const struct sockaddr *from, socklen_t fromlen, const struct sockaddr *to, socklen_t tolen) { struct msghdr msg; struct iovec vec; struct cmsghdr *cmsg; char cmsgbuf[256]; __CTASSERT(sizeof(cmsgbuf) > CMSG_SPACE(sizeof(struct in_pktinfo))); #ifdef INET6 __CTASSERT(sizeof(cmsgbuf) > CMSG_SPACE(sizeof(struct in6_pktinfo))); #endif if (from == NULL || fromlen == 0) return sendto(s, buf, len, flags, to, tolen); vec.iov_base = __UNCONST(buf); vec.iov_len = len; msg.msg_name = __UNCONST(to); msg.msg_namelen = tolen; msg.msg_iov = &vec; msg.msg_iovlen = 1; msg.msg_control = cmsgbuf; msg.msg_controllen = 0; if (fromlen < 2) { /* sa_len + sa_family */ errno = EINVAL; return -1; } cmsg = (struct cmsghdr *)cmsgbuf; if (from->sa_family == AF_INET) { const struct sockaddr_in *from4 = (const struct sockaddr_in *)from; struct in_pktinfo *pi; if (fromlen != sizeof(struct sockaddr_in) || from4->sin_family != AF_INET) { errno = EINVAL; return -1; } msg.msg_controllen += CMSG_SPACE(sizeof(struct in_pktinfo)); cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo)); cmsg->cmsg_level = IPPROTO_IP; cmsg->cmsg_type = IP_PKTINFO; pi = (struct in_pktinfo *)CMSG_DATA(cmsg); pi->ipi_addr = from4->sin_addr; pi->ipi_ifindex = 0; #ifdef INET6 } else if (from->sa_family == AF_INET6) { const struct sockaddr_in6 *from6 = (const struct sockaddr_in6 *)from; struct in6_pktinfo *pi6; if (fromlen != sizeof(struct sockaddr_in6) || from6->sin6_family != AF_INET6) { errno = EINVAL; return -1; } msg.msg_controllen += CMSG_SPACE(sizeof(struct in6_pktinfo)); cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); cmsg->cmsg_level = IPPROTO_IPV6; cmsg->cmsg_type = IPV6_PKTINFO; pi6 = (struct in6_pktinfo *)CMSG_DATA(cmsg); pi6->ipi6_addr = from6->sin6_addr; if (IN6_IS_ADDR_LINKLOCAL(&from6->sin6_addr) || IN6_IS_ADDR_MC_LINKLOCAL(&from6->sin6_addr)) { pi6->ipi6_ifindex = from6->sin6_scope_id; } else { pi6->ipi6_ifindex = 0; } #endif /* INET6 */ } else { return sendto(s, buf, len, flags, to, tolen); } return sendmsg(s, &msg, flags); } /* * Internet services provided internally by inetd: */ #define BUFSIZE 4096 /* ARGSUSED */ static void echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */ { char buffer[BUFSIZE]; ssize_t i; inetd_setproctitle(sep->se_service, s); while ((i = read(s, buffer, sizeof(buffer))) > 0 && write(s, buffer, (size_t)i) > 0) continue; } /* ARGSUSED */ static void echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */ { char buffer[BUFSIZE]; ssize_t i; socklen_t rsize, lsize; struct sockaddr_storage remote, local; struct sockaddr *lsa, *rsa; rsa = (struct sockaddr *)(void *)&remote; lsa = (struct sockaddr *)(void *)&local; rsize = sizeof(remote); lsize = sizeof(local); if ((i = recvfromto(s, buffer, sizeof(buffer), 0, rsa, &rsize, lsa, &lsize)) < 0) return; if (port_good_dg(rsa)) (void) sendfromto(s, buffer, (size_t)i, 0, lsa, lsize, rsa, rsize); } /* ARGSUSED */ static void discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */ { char buffer[BUFSIZE]; inetd_setproctitle(sep->se_service, s); while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || errno == EINTR) ; } /* ARGSUSED */ static void discard_dg(int s, struct servtab *sep) /* Discard service -- ignore data */ { char buffer[BUFSIZE]; (void) read(s, buffer, sizeof(buffer)); } #define LINESIZ 72 char ring[128]; char *endring; static void initring(void) { int i; endring = ring; for (i = 0; i <= 128; ++i) if (isprint(i)) *endring++ = (char)i; } /* ARGSUSED */ static void chargen_stream(int s, struct servtab *sep) /* Character generator */ { size_t len; char *rs, text[LINESIZ+2]; inetd_setproctitle(sep->se_service, s); if (endring == NULL) { initring(); rs = ring; } text[LINESIZ] = '\r'; text[LINESIZ + 1] = '\n'; for (rs = ring;;) { if ((len = (size_t)(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; } } /* ARGSUSED */ static void chargen_dg(int s, struct servtab *sep) /* Character generator */ { struct sockaddr_storage remote, local; struct sockaddr *rsa, *lsa; static char *rs; size_t len; socklen_t rsize, lsize; char text[LINESIZ+2]; if (endring == 0) { initring(); rs = ring; } rsa = (struct sockaddr *)(void *)&remote; lsa = (struct sockaddr *)(void *)&local; rsize = sizeof(remote); lsize = sizeof(local); if (recvfromto(s, text, sizeof(text), 0, rsa, &rsize, lsa, &lsize) < 0) return; if (!port_good_dg(rsa)) return; if ((len = (size_t)(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) sendfromto(s, text, sizeof(text), 0, lsa, lsize, rsa, rsize); } /* * 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. */ static uint32_t machtime(void) { struct timeval tv; if (gettimeofday(&tv, NULL) < 0) { DPRINTF("Unable to get time of day"); return (0); } #define OFFSET ((uint32_t)25567 * 24*60*60) return (htonl((uint32_t)(tv.tv_sec + OFFSET))); #undef OFFSET } /* ARGSUSED */ static void machtime_stream(int s, struct servtab *sep) { uint32_t result; result = machtime(); (void) write(s, &result, sizeof(result)); } /* ARGSUSED */ void machtime_dg(int s, struct servtab *sep) { uint32_t result; struct sockaddr_storage remote, local; struct sockaddr *rsa, *lsa; socklen_t rsize, lsize; rsa = (struct sockaddr *)(void *)&remote; lsa = (struct sockaddr *)(void *)&local; rsize = sizeof(remote); lsize = sizeof(local); if (recvfromto(s, &result, sizeof(result), 0, rsa, &rsize, lsa, &lsize) < 0) return; if (!port_good_dg(rsa)) return; result = machtime(); (void)sendfromto(s, &result, sizeof(result), 0, lsa, lsize, rsa, rsize); } /* ARGSUSED */ static void daytime_stream(int s,struct servtab *sep) /* Return human-readable time of day */ { char buffer[256]; time_t clk; int len; clk = time((time_t *) 0); len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk)); (void) write(s, buffer, (size_t)len); } /* ARGSUSED */ void daytime_dg(int s, struct servtab *sep) /* Return human-readable time of day */ { char buffer[256]; time_t clk; struct sockaddr_storage remote, local; struct sockaddr *rsa, *lsa; socklen_t rsize, lsize; int len; clk = time((time_t *) 0); rsa = (struct sockaddr *)(void *)&remote; lsa = (struct sockaddr *)(void *)&local; rsize = sizeof(remote); lsize = sizeof(local); if (recvfromto(s, buffer, sizeof(buffer), 0, rsa, &rsize, lsa, &lsize) < 0) return; if (!port_good_dg(rsa)) return; len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clk)); (void) sendfromto(s, buffer, (size_t)len, 0, lsa, lsize, rsa, rsize); } static void usage(void) { #ifdef LIBWRAP (void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname()); #else (void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname()); #endif exit(EXIT_FAILURE); } /* * Based on TCPMUX.C by Mark K. Lottor November 1988 * sri-nic::ps:tcpmux.c */ static int /* # of characters upto \r,\n or \0 */ get_line(int fd, char *buf, int len) { int count = 0; ssize_t n; do { n = read(fd, buf, (size_t)(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) static void tcpmux(int ctrl, struct servtab *sep) { char service[MAX_SERV_LEN+1]; int len; /* Get requested service name */ if ((len = get_line(ctrl, service, MAX_SERV_LEN)) < 0) { strwrite(ctrl, "-Error reading service name\r\n"); goto reject; } service[len] = '\0'; DPRINTF("tcpmux: %s: service requested", service); /* * Help is a required command, and lists available services, * one per line. */ if (strcasecmp(service, "help") == 0) { strwrite(ctrl, "+Available services:\r\n"); strwrite(ctrl, "help\r\n"); for (sep = servtab; sep != NULL; sep = sep->se_next) { if (!ISMUX(sep)) continue; (void)write(ctrl, sep->se_service, strlen(sep->se_service)); strwrite(ctrl, "\r\n"); } goto reject; } /* Try matching a service in inetd.conf with the request */ for (sep = servtab; sep != NULL; sep = sep->se_next) { if (!ISMUX(sep)) continue; if (strcasecmp(service, sep->se_service) == 0) { if (ISMUXPLUS(sep)) strwrite(ctrl, "+Go\r\n"); run_service(ctrl, sep, true /* forked */); return; } } strwrite(ctrl, "-Service not available\r\n"); reject: _exit(EXIT_FAILURE); } /* * check if the address/port where send data to is one of the obvious ports * that are used for denial of service attacks like two echo ports * just echoing data between them */ static int port_good_dg(struct sockaddr *sa) { struct in_addr in; struct sockaddr_in *sin; #ifdef INET6 struct in6_addr *in6; struct sockaddr_in6 *sin6; #endif u_int16_t port; int i; char hbuf[NI_MAXHOST]; switch (sa->sa_family) { case AF_INET: sin = (struct sockaddr_in *)(void *)sa; in.s_addr = ntohl(sin->sin_addr.s_addr); port = ntohs(sin->sin_port); #ifdef INET6 v4chk: #endif if (IN_MULTICAST(in.s_addr)) goto bad; switch ((in.s_addr & 0xff000000) >> 24) { case 0: case 127: case 255: goto bad; } if (dg_broadcast(&in)) goto bad; break; #ifdef INET6 case AF_INET6: sin6 = (struct sockaddr_in6 *)(void *)sa; in6 = &sin6->sin6_addr; port = ntohs(sin6->sin6_port); if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6)) goto bad; if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) { memcpy(&in, &in6->s6_addr[12], sizeof(in)); in.s_addr = ntohl(in.s_addr); goto v4chk; } break; #endif default: /* XXX unsupported af, is it safe to assume it to be safe? */ return true; } for (i = 0; bad_ports[i] != 0; i++) { if (port == bad_ports[i]) goto bad; } return true; bad: if (getnameinfo(sa, sa->sa_len, hbuf, (socklen_t)sizeof(hbuf), NULL, 0, niflags) != 0) strlcpy(hbuf, "?", sizeof(hbuf)); syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d", hbuf, port); return false; } /* XXX need optimization */ static int dg_broadcast(struct in_addr *in) { struct ifaddrs *ifa, *ifap; struct sockaddr_in *sin; if (getifaddrs(&ifap) < 0) return false; for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) { if (ifa->ifa_addr->sa_family != AF_INET || (ifa->ifa_flags & IFF_BROADCAST) == 0) continue; sin = (struct sockaddr_in *)(void *)ifa->ifa_broadaddr; if (sin->sin_addr.s_addr == in->s_addr) { freeifaddrs(ifap); return true; } } freeifaddrs(ifap); return false; } static int my_kevent(const struct kevent *changelist, size_t nchanges, struct kevent *eventlist, size_t nevents) { int result; while ((result = kevent(kq, changelist, nchanges, eventlist, nevents, NULL)) < 0) if (errno != EINTR) { syslog(LOG_ERR, "kevent: %m"); exit(EXIT_FAILURE); } return (result); } static struct kevent * allocchange(void) { if (changes == __arraycount(changebuf)) { (void) my_kevent(changebuf, __arraycount(changebuf), NULL, 0); changes = 0; } return (&changebuf[changes++]); } bool try_biltin(struct servtab *sep) { for (size_t i = 0; i < __arraycount(biltins); i++) { if (biltins[i].bi_socktype == sep->se_socktype && strcmp(biltins[i].bi_service, sep->se_service) == 0) { sep->se_bi = &biltins[i]; sep->se_wait = biltins[i].bi_wait; return true; } } return false; }