/* * Copyright (c) 1983, 1988, 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 const char copyright[] = "@(#) Copyright (c) 1983, 1988, 1993, 1994\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint #if 0 static char sccsid[] = "@(#)syslogd.c 8.3 (Berkeley) 4/4/94"; #endif static const char rcsid[] = "$FreeBSD$"; #endif /* not lint */ /* * syslogd -- log system messages * * This program implements a system log. It takes a series of lines. * Each line may have a priority, signified as "" as * the first characters of the line. If this is * not present, a default priority is used. * * To kill syslogd, send a signal 15 (terminate). A signal 1 (hup) will * cause it to reread its configuration file. * * Defined Constants: * * MAXLINE -- the maximimum line length that can be handled. * DEFUPRI -- the default priority for user messages * DEFSPRI -- the default priority for kernel messages * * Author: Eric Allman * extensive changes by Ralph Campbell * more extensive changes by Eric Allman (again) * Extension to log by program name as well as facility and priority * by Peter da Silva. * -u and -v by Harlan Stenn. * Priority comparison code by Harlan Stenn. */ #define MAXLINE 1024 /* maximum line length */ #define MAXSVLINE 120 /* maximum saved line length */ #define DEFUPRI (LOG_USER|LOG_NOTICE) #define DEFSPRI (LOG_KERN|LOG_CRIT) #define TIMERINTVL 30 /* interval for checking flush, mark */ #define TTYMSGTIME 1 /* timed out passed to ttymsg */ #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 #include #include #include #include "pathnames.h" #define SYSLOG_NAMES #include const char *ConfFile = _PATH_LOGCONF; const char *PidFile = _PATH_LOGPID; const char ctty[] = _PATH_CONSOLE; #define dprintf if (Debug) printf #define MAXUNAMES 20 /* maximum number of user names */ #define MAXFUNIX 20 int nfunix = 1; char *funixn[MAXFUNIX] = { _PATH_LOG }; int funix[MAXFUNIX]; /* * Flags to logmsg(). */ #define IGN_CONS 0x001 /* don't print on console */ #define SYNC_FILE 0x002 /* do fsync on file after printing */ #define ADDDATE 0x004 /* add a date to the message */ #define MARK 0x008 /* this message is a mark */ #define ISKERNEL 0x010 /* kernel generated message */ /* * This structure represents the files that will have log * copies printed. */ struct filed { struct filed *f_next; /* next in linked list */ short f_type; /* entry type, see below */ short f_file; /* file descriptor */ time_t f_time; /* time this was last written */ char *f_host; /* host from which to recd. */ u_char f_pmask[LOG_NFACILITIES+1]; /* priority mask */ u_char f_pcmp[LOG_NFACILITIES+1]; /* compare priority */ #define PRI_LT 0x1 #define PRI_EQ 0x2 #define PRI_GT 0x4 char *f_program; /* program this applies to */ union { char f_uname[MAXUNAMES][UT_NAMESIZE+1]; struct { char f_hname[MAXHOSTNAMELEN+1]; struct sockaddr_in f_addr; } f_forw; /* forwarding address */ char f_fname[MAXPATHLEN]; struct { char f_pname[MAXPATHLEN]; pid_t f_pid; } f_pipe; } f_un; char f_prevline[MAXSVLINE]; /* last message logged */ char f_lasttime[16]; /* time of last occurrence */ char f_prevhost[MAXHOSTNAMELEN+1]; /* host from which recd. */ int f_prevpri; /* pri of f_prevline */ int f_prevlen; /* length of f_prevline */ int f_prevcount; /* repetition cnt of prevline */ int f_repeatcount; /* number of "repeated" msgs */ }; /* * Queue of about-to-be dead processes we should watch out for. */ TAILQ_HEAD(stailhead, deadq_entry) deadq_head; struct stailhead *deadq_headp; struct deadq_entry { pid_t dq_pid; int dq_timeout; TAILQ_ENTRY(deadq_entry) dq_entries; }; /* * The timeout to apply to processes waiting on the dead queue. Unit * of measure is `mark intervals', i.e. 20 minutes by default. * Processes on the dead queue will be terminated after that time. */ #define DQ_TIMO_INIT 2 typedef struct deadq_entry *dq_t; /* * Struct to hold records of network addresses that are allowed to log * to us. */ struct allowedpeer { int isnumeric; u_short port; union { struct { struct in_addr addr; struct in_addr mask; } numeric; char *name; } u; #define a_addr u.numeric.addr #define a_mask u.numeric.mask #define a_name u.name }; /* * Intervals at which we flush out "message repeated" messages, * in seconds after previous message is logged. After each flush, * we move to the next interval until we reach the largest. */ int repeatinterval[] = { 30, 120, 600 }; /* # of secs before flush */ #define MAXREPEAT ((sizeof(repeatinterval) / sizeof(repeatinterval[0])) - 1) #define REPEATTIME(f) ((f)->f_time + repeatinterval[(f)->f_repeatcount]) #define BACKOFF(f) { if (++(f)->f_repeatcount > MAXREPEAT) \ (f)->f_repeatcount = MAXREPEAT; \ } /* values for f_type */ #define F_UNUSED 0 /* unused entry */ #define F_FILE 1 /* regular file */ #define F_TTY 2 /* terminal */ #define F_CONSOLE 3 /* console terminal */ #define F_FORW 4 /* remote machine */ #define F_USERS 5 /* list of users */ #define F_WALL 6 /* everyone logged on */ #define F_PIPE 7 /* pipe to program */ char *TypeNames[8] = { "UNUSED", "FILE", "TTY", "CONSOLE", "FORW", "USERS", "WALL", "PIPE" }; struct filed *Files; struct filed consfile; int Debug; /* debug flag */ int resolve = 1; /* resolve hostname */ char LocalHostName[MAXHOSTNAMELEN+1]; /* our hostname */ char *LocalDomain; /* our local domain name */ int finet = -1; /* Internet datagram socket */ int fklog = -1; /* /dev/klog */ int LogPort; /* port number for INET connections */ int Initialized = 0; /* set when we have initialized ourselves */ int MarkInterval = 20 * 60; /* interval between marks in seconds */ int MarkSeq = 0; /* mark sequence number */ int SecureMode = 0; /* when true, receive only unix domain socks */ char bootfile[MAXLINE+1]; /* booted kernel file */ struct allowedpeer *AllowedPeers; int NumAllowed = 0; /* # of AllowedPeer entries */ int UniquePriority = 0; /* Only log specified priority? */ int LogFacPri = 0; /* Put facility and priority in log message: */ /* 0=no, 1=numeric, 2=names */ int KeepKernFac = 0; /* Keep remotely logged kernel facility */ int allowaddr __P((char *)); void cfline __P((char *, struct filed *, char *, char *)); char *cvthname __P((struct sockaddr_in *)); void deadq_enter __P((pid_t, const char *)); int deadq_remove __P((pid_t)); int decode __P((const char *, CODE *)); void die __P((int)); void domark __P((int)); void fprintlog __P((struct filed *, int, char *)); void init __P((int)); void logerror __P((const char *)); void logmsg __P((int, char *, char *, int)); void log_deadchild __P((pid_t, int, const char *)); void printline __P((char *, char *)); void printsys __P((char *)); int p_open __P((char *, pid_t *)); void readklog __P((void)); void reapchild __P((int)); char *ttymsg __P((struct iovec *, int, char *, int)); static void usage __P((void)); int validate __P((struct sockaddr_in *, const char *)); void wallmsg __P((struct filed *, struct iovec *)); int waitdaemon __P((int, int, int)); void timedout __P((int)); int main(argc, argv) int argc; char *argv[]; { int ch, i, l; struct sockaddr_un sunx, fromunix; struct sockaddr_in sin, frominet; FILE *fp; char *p, *hname, line[MAXLINE + 1]; struct timeval tv, *tvp; struct sigaction sact; sigset_t mask; pid_t ppid = 1; socklen_t len; while ((ch = getopt(argc, argv, "a:df:kl:m:np:suv")) != -1) switch (ch) { case 'a': /* allow specific network addresses only */ if (allowaddr(optarg) == -1) usage(); break; case 'd': /* debug */ Debug++; break; case 'f': /* configuration file */ ConfFile = optarg; break; case 'k': /* keep remote kern fac */ KeepKernFac = 1; break; case 'l': if (nfunix < MAXFUNIX) funixn[nfunix++] = optarg; else warnx("out of descriptors, ignoring %s", optarg); break; case 'm': /* mark interval */ MarkInterval = atoi(optarg) * 60; break; case 'n': resolve = 0; break; case 'p': /* path */ funixn[0] = optarg; break; case 's': /* no network mode */ SecureMode++; break; case 'u': /* only log specified priority */ UniquePriority++; break; case 'v': /* log facility and priority */ LogFacPri++; break; case '?': default: usage(); } if ((argc -= optind) != 0) usage(); if (!Debug) { ppid = waitdaemon(0, 0, 30); if (ppid < 0) err(1, "could not become daemon"); } else setlinebuf(stdout); if (NumAllowed) endservent(); consfile.f_type = F_CONSOLE; (void)strcpy(consfile.f_un.f_fname, ctty + sizeof _PATH_DEV - 1); (void)gethostname(LocalHostName, sizeof(LocalHostName)); if ((p = strchr(LocalHostName, '.')) != NULL) { *p++ = '\0'; LocalDomain = p; } else LocalDomain = ""; (void)strcpy(bootfile, getbootfile()); (void)signal(SIGTERM, die); (void)signal(SIGINT, Debug ? die : SIG_IGN); (void)signal(SIGQUIT, Debug ? die : SIG_IGN); /* * We don't want the SIGCHLD and SIGHUP handlers to interfere * with each other; they are likely candidates for being called * simultaneously (SIGHUP closes pipe descriptor, process dies, * SIGCHLD happens). */ sigemptyset(&mask); sigaddset(&mask, SIGHUP); sact.sa_handler = reapchild; sact.sa_mask = mask; sact.sa_flags = SA_RESTART; (void)sigaction(SIGCHLD, &sact, NULL); (void)signal(SIGALRM, domark); (void)signal(SIGPIPE, SIG_IGN); /* We'll catch EPIPE instead. */ (void)alarm(TIMERINTVL); TAILQ_INIT(&deadq_head); #ifndef SUN_LEN #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2) #endif for (i = 0; i < nfunix; i++) { memset(&sunx, 0, sizeof(sunx)); sunx.sun_family = AF_UNIX; (void)strncpy(sunx.sun_path, funixn[i], sizeof(sunx.sun_path)); funix[i] = socket(AF_UNIX, SOCK_DGRAM, 0); if (funix[i] < 0 || bind(funix[i], (struct sockaddr *)&sunx, SUN_LEN(&sunx)) < 0 || chmod(funixn[i], 0666) < 0) { (void) snprintf(line, sizeof line, "cannot create %s", funixn[i]); logerror(line); dprintf("cannot create %s (%d)\n", funixn[i], errno); if (i == 0) die(0); } } if (SecureMode <= 1) finet = socket(AF_INET, SOCK_DGRAM, 0); if (finet >= 0) { struct servent *sp; sp = getservbyname("syslog", "udp"); if (sp == NULL) { errno = 0; logerror("syslog/udp: unknown service"); die(0); } memset(&sin, 0, sizeof(sin)); sin.sin_family = AF_INET; sin.sin_port = LogPort = sp->s_port; if (bind(finet, (struct sockaddr *)&sin, sizeof(sin)) < 0) { logerror("bind"); if (!Debug) die(0); } } if (finet >= 0 && SecureMode) { if (shutdown(finet, SHUT_RD) < 0) { logerror("shutdown"); if (!Debug) die(0); } } if ((fklog = open(_PATH_KLOG, O_RDONLY, 0)) >= 0) if (fcntl(fklog, F_SETFL, O_NONBLOCK) < 0) fklog = -1; if (fklog < 0) dprintf("can't open %s (%d)\n", _PATH_KLOG, errno); /* tuck my process id away */ fp = fopen(PidFile, "w"); if (fp != NULL) { fprintf(fp, "%d\n", getpid()); (void) fclose(fp); } dprintf("off & running....\n"); init(0); /* prevent SIGHUP and SIGCHLD handlers from running in parallel */ sigemptyset(&mask); sigaddset(&mask, SIGCHLD); sact.sa_handler = init; sact.sa_mask = mask; sact.sa_flags = SA_RESTART; (void)sigaction(SIGHUP, &sact, NULL); tvp = &tv; tv.tv_sec = tv.tv_usec = 0; for (;;) { fd_set readfds; int nfds = 0; FD_ZERO(&readfds); if (fklog != -1) { FD_SET(fklog, &readfds); if (fklog > nfds) nfds = fklog; } if (finet != -1 && !SecureMode) { FD_SET(finet, &readfds); if (finet > nfds) nfds = finet; } for (i = 0; i < nfunix; i++) { if (funix[i] != -1) { FD_SET(funix[i], &readfds); if (funix[i] > nfds) nfds = funix[i]; } } /*dprintf("readfds = %#x\n", readfds);*/ nfds = select(nfds+1, &readfds, (fd_set *)NULL, (fd_set *)NULL, tvp); if (nfds == 0) { if (tvp) { tvp = NULL; if (ppid != 1) kill(ppid, SIGALRM); } continue; } if (nfds < 0) { if (errno != EINTR) logerror("select"); continue; } /*dprintf("got a message (%d, %#x)\n", nfds, readfds);*/ if (fklog != -1 && FD_ISSET(fklog, &readfds)) readklog(); if (finet != -1 && FD_ISSET(finet, &readfds)) { len = sizeof(frominet); l = recvfrom(finet, line, MAXLINE, 0, (struct sockaddr *)&frominet, &len); if (l > 0) { line[l] = '\0'; if (resolve) hname = cvthname(&frominet); else hname = inet_ntoa(frominet.sin_addr); if (validate(&frominet, hname)) printline(hname, line); } else if (l < 0 && errno != EINTR) logerror("recvfrom inet"); } for (i = 0; i < nfunix; i++) { if (funix[i] != -1 && FD_ISSET(funix[i], &readfds)) { len = sizeof(fromunix); l = recvfrom(funix[i], line, MAXLINE, 0, (struct sockaddr *)&fromunix, &len); if (l > 0) { line[l] = '\0'; printline(LocalHostName, line); } else if (l < 0 && errno != EINTR) logerror("recvfrom unix"); } } } } static void usage() { fprintf(stderr, "%s\n%s\n%s\n", "usage: syslogd [-dnsuv] [-a allowed_peer] [-f config_file]", " [-m mark_interval] [-p log_socket]", " [-l log_socket]"); exit(1); } /* * Take a raw input line, decode the message, and print the message * on the appropriate log files. */ void printline(hname, msg) char *hname; char *msg; { int c, pri; char *p, *q, line[MAXLINE + 1]; /* test for special codes */ pri = DEFUPRI; p = msg; if (*p == '<') { pri = 0; while (isdigit(*++p)) pri = 10 * pri + (*p - '0'); if (*p == '>') ++p; } if (pri &~ (LOG_FACMASK|LOG_PRIMASK)) pri = DEFUPRI; /* don't allow users to log kernel messages */ if (LOG_FAC(pri) == LOG_KERN && !KeepKernFac) pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri)); q = line; while ((c = (unsigned char)*p++) != '\0' && q < &line[sizeof(line) - 4]) { if ((c & 0x80) && c < 0xA0) { c &= 0x7F; *q++ = 'M'; *q++ = '-'; } if (isascii(c) && iscntrl(c)) { if (c == '\n') *q++ = ' '; else if (c == '\t') *q++ = '\t'; else { *q++ = '^'; *q++ = c ^ 0100; } } else *q++ = c; } *q = '\0'; logmsg(pri, line, hname, 0); } /* * Read /dev/klog while data are available, split into lines. */ void readklog() { char *p, *q, line[MAXLINE + 1]; int len, i; len = 0; for (;;) { i = read(fklog, line + len, MAXLINE - 1 - len); if (i > 0) line[i + len] = '\0'; else if (i < 0 && errno != EINTR && errno != EAGAIN) { logerror("klog"); fklog = -1; break; } else break; for (p = line; (q = strchr(p, '\n')) != NULL; p = q + 1) { *q = '\0'; printsys(p); } len = strlen(p); if (len >= MAXLINE - 1) { printsys(p); len = 0; } if (len > 0) memmove(line, p, len + 1); } if (len > 0) printsys(line); } /* * Take a raw input line from /dev/klog, format similar to syslog(). */ void printsys(p) char *p; { int pri, flags; flags = ISKERNEL | SYNC_FILE | ADDDATE; /* fsync after write */ pri = DEFSPRI; if (*p == '<') { pri = 0; while (isdigit(*++p)) pri = 10 * pri + (*p - '0'); if (*p == '>') ++p; } else { /* kernel printf's come out on console */ flags |= IGN_CONS; } if (pri &~ (LOG_FACMASK|LOG_PRIMASK)) pri = DEFSPRI; logmsg(pri, p, LocalHostName, flags); } time_t now; /* * Log a message to the appropriate log files, users, etc. based on * the priority. */ void logmsg(pri, msg, from, flags) int pri; char *msg, *from; int flags; { struct filed *f; int i, fac, msglen, omask, prilev; char *timestamp; char prog[NAME_MAX+1]; char buf[MAXLINE+1]; dprintf("logmsg: pri %o, flags %x, from %s, msg %s\n", pri, flags, from, msg); omask = sigblock(sigmask(SIGHUP)|sigmask(SIGALRM)); /* * Check to see if msg looks non-standard. */ msglen = strlen(msg); if (msglen < 16 || msg[3] != ' ' || msg[6] != ' ' || msg[9] != ':' || msg[12] != ':' || msg[15] != ' ') flags |= ADDDATE; (void)time(&now); if (flags & ADDDATE) timestamp = ctime(&now) + 4; else { timestamp = msg; msg += 16; msglen -= 16; } /* skip leading blanks */ while (isspace(*msg)) { msg++; msglen--; } /* extract facility and priority level */ if (flags & MARK) fac = LOG_NFACILITIES; else fac = LOG_FAC(pri); prilev = LOG_PRI(pri); /* extract program name */ for (i = 0; i < NAME_MAX; i++) { if (!isalnum(msg[i])) break; prog[i] = msg[i]; } prog[i] = 0; /* add kernel prefix for kernel messages */ if (flags & ISKERNEL) { snprintf(buf, sizeof(buf), "%s: %s", bootfile, msg); msg = buf; msglen = strlen(buf); } /* log the message to the particular outputs */ if (!Initialized) { f = &consfile; f->f_file = open(ctty, O_WRONLY, 0); if (f->f_file >= 0) { fprintlog(f, flags, msg); (void)close(f->f_file); } (void)sigsetmask(omask); return; } for (f = Files; f; f = f->f_next) { /* skip messages that are incorrect priority */ if (!(((f->f_pcmp[fac] & PRI_EQ) && (f->f_pmask[fac] == prilev)) ||((f->f_pcmp[fac] & PRI_LT) && (f->f_pmask[fac] < prilev)) ||((f->f_pcmp[fac] & PRI_GT) && (f->f_pmask[fac] > prilev)) ) || f->f_pmask[fac] == INTERNAL_NOPRI) continue; /* skip messages with the incorrect hostname */ if (f->f_host) switch (f->f_host[0]) { case '+': if (strcmp(from, f->f_host + 1) != 0) continue; break; case '-': if (strcmp(from, f->f_host + 1) == 0) continue; break; } /* skip messages with the incorrect program name */ if (f->f_program) if (strcmp(prog, f->f_program) != 0) continue; if (f->f_type == F_CONSOLE && (flags & IGN_CONS)) continue; /* don't output marks to recently written files */ if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2) continue; /* * suppress duplicate lines to this file */ if ((flags & MARK) == 0 && msglen == f->f_prevlen && !strcmp(msg, f->f_prevline) && !strcasecmp(from, f->f_prevhost)) { (void)strncpy(f->f_lasttime, timestamp, 15); f->f_prevcount++; dprintf("msg repeated %d times, %ld sec of %d\n", f->f_prevcount, (long)(now - f->f_time), repeatinterval[f->f_repeatcount]); /* * If domark would have logged this by now, * flush it now (so we don't hold isolated messages), * but back off so we'll flush less often * in the future. */ if (now > REPEATTIME(f)) { fprintlog(f, flags, (char *)NULL); BACKOFF(f); } } else { /* new line, save it */ if (f->f_prevcount) fprintlog(f, 0, (char *)NULL); f->f_repeatcount = 0; f->f_prevpri = pri; (void)strncpy(f->f_lasttime, timestamp, 15); (void)strncpy(f->f_prevhost, from, sizeof(f->f_prevhost)-1); f->f_prevhost[sizeof(f->f_prevhost)-1] = '\0'; if (msglen < MAXSVLINE) { f->f_prevlen = msglen; (void)strcpy(f->f_prevline, msg); fprintlog(f, flags, (char *)NULL); } else { f->f_prevline[0] = 0; f->f_prevlen = 0; fprintlog(f, flags, msg); } } } (void)sigsetmask(omask); } void fprintlog(f, flags, msg) struct filed *f; int flags; char *msg; { struct iovec iov[7]; struct iovec *v; int l; char line[MAXLINE + 1], repbuf[80], greetings[200]; char *msgret; v = iov; if (f->f_type == F_WALL) { v->iov_base = greetings; v->iov_len = snprintf(greetings, sizeof greetings, "\r\n\7Message from syslogd@%s at %.24s ...\r\n", f->f_prevhost, ctime(&now)); v++; v->iov_base = ""; v->iov_len = 0; v++; } else { v->iov_base = f->f_lasttime; v->iov_len = 15; v++; v->iov_base = " "; v->iov_len = 1; v++; } if (LogFacPri) { static char fp_buf[30]; /* Hollow laugh */ int fac = f->f_prevpri & LOG_FACMASK; int pri = LOG_PRI(f->f_prevpri); char *f_s = 0; char f_n[5]; /* Hollow laugh */ char *p_s = 0; char p_n[5]; /* Hollow laugh */ if (LogFacPri > 1) { CODE *c; for (c = facilitynames; c->c_name; c++) { if (c->c_val == fac) { f_s = c->c_name; break; } } for (c = prioritynames; c->c_name; c++) { if (c->c_val == pri) { p_s = c->c_name; break; } } } if (!f_s) { snprintf(f_n, sizeof f_n, "%d", LOG_FAC(fac)); f_s = f_n; } if (!p_s) { snprintf(p_n, sizeof p_n, "%d", pri); p_s = p_n; } snprintf(fp_buf, sizeof fp_buf, "<%s.%s> ", f_s, p_s); v->iov_base = fp_buf; v->iov_len = strlen(fp_buf); } else { v->iov_base=""; v->iov_len = 0; } v++; v->iov_base = f->f_prevhost; v->iov_len = strlen(v->iov_base); v++; v->iov_base = " "; v->iov_len = 1; v++; if (msg) { v->iov_base = msg; v->iov_len = strlen(msg); } else if (f->f_prevcount > 1) { v->iov_base = repbuf; v->iov_len = sprintf(repbuf, "last message repeated %d times", f->f_prevcount); } else { v->iov_base = f->f_prevline; v->iov_len = f->f_prevlen; } v++; dprintf("Logging to %s", TypeNames[f->f_type]); f->f_time = now; switch (f->f_type) { case F_UNUSED: dprintf("\n"); break; case F_FORW: dprintf(" %s\n", f->f_un.f_forw.f_hname); /* check for local vs remote messages */ if (strcasecmp(f->f_prevhost, LocalHostName)) l = snprintf(line, sizeof line - 1, "<%d>%.15s Forwarded from %s: %s", f->f_prevpri, iov[0].iov_base, f->f_prevhost, iov[5].iov_base); else l = snprintf(line, sizeof line - 1, "<%d>%.15s %s", f->f_prevpri, iov[0].iov_base, iov[5].iov_base); if (l > MAXLINE) l = MAXLINE; if ((finet >= 0) && (sendto(finet, line, l, 0, (struct sockaddr *)&f->f_un.f_forw.f_addr, sizeof(f->f_un.f_forw.f_addr)) != l)) { int e = errno; (void)close(f->f_file); f->f_type = F_UNUSED; errno = e; logerror("sendto"); } break; case F_FILE: dprintf(" %s\n", f->f_un.f_fname); v->iov_base = "\n"; v->iov_len = 1; if (writev(f->f_file, iov, 7) < 0) { int e = errno; (void)close(f->f_file); f->f_type = F_UNUSED; errno = e; logerror(f->f_un.f_fname); } else if (flags & SYNC_FILE) (void)fsync(f->f_file); break; case F_PIPE: dprintf(" %s\n", f->f_un.f_pipe.f_pname); v->iov_base = "\n"; v->iov_len = 1; if (f->f_un.f_pipe.f_pid == 0) { if ((f->f_file = p_open(f->f_un.f_pipe.f_pname, &f->f_un.f_pipe.f_pid)) < 0) { f->f_type = F_UNUSED; logerror(f->f_un.f_pipe.f_pname); break; } } if (writev(f->f_file, iov, 7) < 0) { int e = errno; (void)close(f->f_file); if (f->f_un.f_pipe.f_pid > 0) deadq_enter(f->f_un.f_pipe.f_pid, f->f_un.f_pipe.f_pname); f->f_un.f_pipe.f_pid = 0; errno = e; logerror(f->f_un.f_pipe.f_pname); } break; case F_CONSOLE: if (flags & IGN_CONS) { dprintf(" (ignored)\n"); break; } /* FALLTHROUGH */ case F_TTY: dprintf(" %s%s\n", _PATH_DEV, f->f_un.f_fname); v->iov_base = "\r\n"; v->iov_len = 2; errno = 0; /* ttymsg() only sometimes returns an errno */ if ((msgret = ttymsg(iov, 7, f->f_un.f_fname, 10))) { f->f_type = F_UNUSED; logerror(msgret); } break; case F_USERS: case F_WALL: dprintf("\n"); v->iov_base = "\r\n"; v->iov_len = 2; wallmsg(f, iov); break; } f->f_prevcount = 0; } /* * WALLMSG -- Write a message to the world at large * * Write the specified message to either the entire * world, or a list of approved users. */ void wallmsg(f, iov) struct filed *f; struct iovec *iov; { static int reenter; /* avoid calling ourselves */ FILE *uf; struct utmp ut; int i; char *p; char line[sizeof(ut.ut_line) + 1]; if (reenter++) return; if ((uf = fopen(_PATH_UTMP, "r")) == NULL) { logerror(_PATH_UTMP); reenter = 0; return; } /* NOSTRICT */ while (fread((char *)&ut, sizeof(ut), 1, uf) == 1) { if (ut.ut_name[0] == '\0') continue; strncpy(line, ut.ut_line, sizeof(ut.ut_line)); line[sizeof(ut.ut_line)] = '\0'; if (f->f_type == F_WALL) { if ((p = ttymsg(iov, 7, line, TTYMSGTIME)) != NULL) { errno = 0; /* already in msg */ logerror(p); } continue; } /* should we send the message to this user? */ for (i = 0; i < MAXUNAMES; i++) { if (!f->f_un.f_uname[i][0]) break; if (!strncmp(f->f_un.f_uname[i], ut.ut_name, UT_NAMESIZE)) { if ((p = ttymsg(iov, 7, line, TTYMSGTIME)) != NULL) { errno = 0; /* already in msg */ logerror(p); } break; } } } (void)fclose(uf); reenter = 0; } void reapchild(signo) int signo; { int status; pid_t pid; struct filed *f; while ((pid = wait3(&status, WNOHANG, (struct rusage *)NULL)) > 0) { if (!Initialized) /* Don't tell while we are initting. */ continue; /* First, look if it's a process from the dead queue. */ if (deadq_remove(pid)) goto oncemore; /* Now, look in list of active processes. */ for (f = Files; f; f = f->f_next) if (f->f_type == F_PIPE && f->f_un.f_pipe.f_pid == pid) { (void)close(f->f_file); f->f_un.f_pipe.f_pid = 0; log_deadchild(pid, status, f->f_un.f_pipe.f_pname); break; } oncemore: continue; } } /* * Return a printable representation of a host address. */ char * cvthname(f) struct sockaddr_in *f; { struct hostent *hp; sigset_t omask, nmask; char *p; dprintf("cvthname(%s)\n", inet_ntoa(f->sin_addr)); if (f->sin_family != AF_INET) { dprintf("Malformed from address\n"); return ("???"); } sigemptyset(&nmask); sigaddset(&nmask, SIGHUP); sigprocmask(SIG_BLOCK, &nmask, &omask); hp = gethostbyaddr((char *)&f->sin_addr, sizeof(struct in_addr), f->sin_family); sigprocmask(SIG_SETMASK, &omask, NULL); if (hp == 0) { dprintf("Host name for your address (%s) unknown\n", inet_ntoa(f->sin_addr)); return (inet_ntoa(f->sin_addr)); } if ((p = strchr(hp->h_name, '.')) && strcasecmp(p + 1, LocalDomain) == 0) *p = '\0'; return (hp->h_name); } void domark(signo) int signo; { struct filed *f; dq_t q; now = time((time_t *)NULL); MarkSeq += TIMERINTVL; if (MarkSeq >= MarkInterval) { logmsg(LOG_INFO, "-- MARK --", LocalHostName, ADDDATE|MARK); MarkSeq = 0; } for (f = Files; f; f = f->f_next) { if (f->f_prevcount && now >= REPEATTIME(f)) { dprintf("flush %s: repeated %d times, %d sec.\n", TypeNames[f->f_type], f->f_prevcount, repeatinterval[f->f_repeatcount]); fprintlog(f, 0, (char *)NULL); BACKOFF(f); } } /* Walk the dead queue, and see if we should signal somebody. */ for (q = TAILQ_FIRST(&deadq_head); q != NULL; q = TAILQ_NEXT(q, dq_entries)) switch (q->dq_timeout) { case 0: /* Already signalled once, try harder now. */ if (kill(q->dq_pid, SIGKILL) != 0) (void)deadq_remove(q->dq_pid); break; case 1: /* * Timed out on dead queue, send terminate * signal. Note that we leave the removal * from the dead queue to reapchild(), which * will also log the event (unless the process * didn't even really exist, in case we simply * drop it from the dead queue). */ if (kill(q->dq_pid, SIGTERM) != 0) (void)deadq_remove(q->dq_pid); /* FALLTHROUGH */ default: q->dq_timeout--; } (void)alarm(TIMERINTVL); } /* * Print syslogd errors some place. */ void logerror(type) const char *type; { char buf[512]; if (errno) (void)snprintf(buf, sizeof buf, "syslogd: %s: %s", type, strerror(errno)); else (void)snprintf(buf, sizeof buf, "syslogd: %s", type); errno = 0; dprintf("%s\n", buf); logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE); } void die(signo) int signo; { struct filed *f; int was_initialized; char buf[100]; int i; was_initialized = Initialized; Initialized = 0; /* Don't log SIGCHLDs. */ for (f = Files; f != NULL; f = f->f_next) { /* flush any pending output */ if (f->f_prevcount) fprintlog(f, 0, (char *)NULL); if (f->f_type == F_PIPE) (void)close(f->f_file); } Initialized = was_initialized; if (signo) { dprintf("syslogd: exiting on signal %d\n", signo); (void)sprintf(buf, "exiting on signal %d", signo); errno = 0; logerror(buf); } for (i = 0; i < nfunix; i++) if (funixn[i] && funix[i] != -1) (void)unlink(funixn[i]); exit(1); } /* * INIT -- Initialize syslogd from configuration table */ void init(signo) int signo; { int i; FILE *cf; struct filed *f, *next, **nextp; char *p; char cline[LINE_MAX]; char prog[NAME_MAX+1]; char host[MAXHOSTNAMELEN+1]; dprintf("init\n"); /* * Close all open log files. */ Initialized = 0; for (f = Files; f != NULL; f = next) { /* flush any pending output */ if (f->f_prevcount) fprintlog(f, 0, (char *)NULL); switch (f->f_type) { case F_FILE: case F_FORW: case F_CONSOLE: case F_TTY: (void)close(f->f_file); break; case F_PIPE: (void)close(f->f_file); if (f->f_un.f_pipe.f_pid > 0) deadq_enter(f->f_un.f_pipe.f_pid, f->f_un.f_pipe.f_pname); f->f_un.f_pipe.f_pid = 0; break; } next = f->f_next; if (f->f_program) free(f->f_program); if (f->f_host) free(f->f_host); free((char *)f); } Files = NULL; nextp = &Files; /* open the configuration file */ if ((cf = fopen(ConfFile, "r")) == NULL) { dprintf("cannot open %s\n", ConfFile); *nextp = (struct filed *)calloc(1, sizeof(*f)); cfline("*.ERR\t/dev/console", *nextp, "*", "*"); (*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f)); cfline("*.PANIC\t*", (*nextp)->f_next, "*", "*"); Initialized = 1; return; } /* * Foreach line in the conf table, open that file. */ f = NULL; strcpy(host, "*"); strcpy(prog, "*"); while (fgets(cline, sizeof(cline), cf) != NULL) { /* * check for end-of-section, comments, strip off trailing * spaces and newline character. #!prog is treated specially: * following lines apply only to that program. */ for (p = cline; isspace(*p); ++p) continue; if (*p == 0) continue; if (*p == '#') { p++; if (*p != '!' && *p != '+' && *p != '-') continue; } if (*p == '+' || *p == '-') { host[0] = *p++; while (isspace(*p)) p++; if ((!*p) || (*p == '*')) { strcpy(host, "*"); continue; } if (*p == '@') p = LocalHostName; for (i = 1; i < MAXHOSTNAMELEN; i++) { if (!isalnum(*p) && *p != '.' && *p != '-') break; host[i] = *p++; } host[i] = '\0'; continue; } if (*p == '!') { p++; while (isspace(*p)) p++; if ((!*p) || (*p == '*')) { strcpy(prog, "*"); continue; } for (i = 0; i < NAME_MAX; i++) { if (!isalnum(p[i])) break; prog[i] = p[i]; } prog[i] = 0; continue; } for (p = strchr(cline, '\0'); isspace(*--p);) continue; *++p = '\0'; f = (struct filed *)calloc(1, sizeof(*f)); *nextp = f; nextp = &f->f_next; cfline(cline, f, prog, host); } /* close the configuration file */ (void)fclose(cf); Initialized = 1; if (Debug) { for (f = Files; f; f = f->f_next) { for (i = 0; i <= LOG_NFACILITIES; i++) if (f->f_pmask[i] == INTERNAL_NOPRI) printf("X "); else printf("%d ", f->f_pmask[i]); printf("%s: ", TypeNames[f->f_type]); switch (f->f_type) { case F_FILE: printf("%s", f->f_un.f_fname); break; case F_CONSOLE: case F_TTY: printf("%s%s", _PATH_DEV, f->f_un.f_fname); break; case F_FORW: printf("%s", f->f_un.f_forw.f_hname); break; case F_PIPE: printf("%s", f->f_un.f_pipe.f_pname); break; case F_USERS: for (i = 0; i < MAXUNAMES && *f->f_un.f_uname[i]; i++) printf("%s, ", f->f_un.f_uname[i]); break; } if (f->f_program) printf(" (%s)", f->f_program); printf("\n"); } } logmsg(LOG_SYSLOG|LOG_INFO, "syslogd: restart", LocalHostName, ADDDATE); dprintf("syslogd: restarted\n"); } /* * Crack a configuration file line */ void cfline(line, f, prog, host) char *line; struct filed *f; char *prog; char *host; { struct hostent *hp; int i, pri; char *bp, *p, *q; char buf[MAXLINE], ebuf[100]; dprintf("cfline(\"%s\", f, \"%s\", \"%s\")\n", line, prog, host); errno = 0; /* keep strerror() stuff out of logerror messages */ /* clear out file entry */ memset(f, 0, sizeof(*f)); for (i = 0; i <= LOG_NFACILITIES; i++) f->f_pmask[i] = INTERNAL_NOPRI; /* save hostname if any */ if (host && *host == '*') host = NULL; if (host) f->f_host = strdup(host); /* save program name if any */ if (prog && *prog == '*') prog = NULL; if (prog) f->f_program = strdup(prog); /* scan through the list of selectors */ for (p = line; *p && *p != '\t' && *p != ' ';) { int pri_done; int pri_cmp; /* find the end of this facility name list */ for (q = p; *q && *q != '\t' && *q != ' ' && *q++ != '.'; ) continue; /* get the priority comparison */ pri_cmp = 0; pri_done = 0; while (!pri_done) { switch (*q) { case '<': pri_cmp |= PRI_LT; q++; break; case '=': pri_cmp |= PRI_EQ; q++; break; case '>': pri_cmp |= PRI_GT; q++; break; default: pri_done++; break; } } if (!pri_cmp) pri_cmp = (UniquePriority) ? (PRI_EQ) : (PRI_EQ | PRI_GT) ; /* collect priority name */ for (bp = buf; *q && !strchr("\t,; ", *q); ) *bp++ = *q++; *bp = '\0'; /* skip cruft */ while (strchr(",;", *q)) q++; /* decode priority name */ if (*buf == '*') pri = LOG_PRIMASK + 1; else { pri = decode(buf, prioritynames); if (pri < 0) { (void)snprintf(ebuf, sizeof ebuf, "unknown priority name \"%s\"", buf); logerror(ebuf); return; } } /* scan facilities */ while (*p && !strchr("\t.; ", *p)) { for (bp = buf; *p && !strchr("\t,;. ", *p); ) *bp++ = *p++; *bp = '\0'; if (*buf == '*') for (i = 0; i < LOG_NFACILITIES; i++) { f->f_pmask[i] = pri; f->f_pcmp[i] = pri_cmp; } else { i = decode(buf, facilitynames); if (i < 0) { (void)snprintf(ebuf, sizeof ebuf, "unknown facility name \"%s\"", buf); logerror(ebuf); return; } f->f_pmask[i >> 3] = pri; f->f_pcmp[i >> 3] = pri_cmp; } while (*p == ',' || *p == ' ') p++; } p = q; } /* skip to action part */ while (*p == '\t' || *p == ' ') p++; switch (*p) { case '@': (void)strncpy(f->f_un.f_forw.f_hname, ++p, sizeof(f->f_un.f_forw.f_hname)-1); f->f_un.f_forw.f_hname[sizeof(f->f_un.f_forw.f_hname)-1] = '\0'; hp = gethostbyname(f->f_un.f_forw.f_hname); if (hp == NULL) { logerror(hstrerror(h_errno)); break; } memset(&f->f_un.f_forw.f_addr, 0, sizeof(f->f_un.f_forw.f_addr)); f->f_un.f_forw.f_addr.sin_family = AF_INET; f->f_un.f_forw.f_addr.sin_port = LogPort; memmove(&f->f_un.f_forw.f_addr.sin_addr, hp->h_addr, hp->h_length); f->f_type = F_FORW; break; case '/': if ((f->f_file = open(p, O_WRONLY|O_APPEND, 0)) < 0) { f->f_type = F_UNUSED; logerror(p); break; } if (isatty(f->f_file)) { if (strcmp(p, ctty) == 0) f->f_type = F_CONSOLE; else f->f_type = F_TTY; (void)strcpy(f->f_un.f_fname, p + sizeof _PATH_DEV - 1); } else { (void)strcpy(f->f_un.f_fname, p); f->f_type = F_FILE; } break; case '|': f->f_un.f_pipe.f_pid = 0; (void)strcpy(f->f_un.f_pipe.f_pname, p + 1); f->f_type = F_PIPE; break; case '*': f->f_type = F_WALL; break; default: for (i = 0; i < MAXUNAMES && *p; i++) { for (q = p; *q && *q != ','; ) q++; (void)strncpy(f->f_un.f_uname[i], p, UT_NAMESIZE); if ((q - p) > UT_NAMESIZE) f->f_un.f_uname[i][UT_NAMESIZE] = '\0'; else f->f_un.f_uname[i][q - p] = '\0'; while (*q == ',' || *q == ' ') q++; p = q; } f->f_type = F_USERS; break; } } /* * Decode a symbolic name to a numeric value */ int decode(name, codetab) const char *name; CODE *codetab; { CODE *c; char *p, buf[40]; if (isdigit(*name)) return (atoi(name)); for (p = buf; *name && p < &buf[sizeof(buf) - 1]; p++, name++) { if (isupper(*name)) *p = tolower(*name); else *p = *name; } *p = '\0'; for (c = codetab; c->c_name; c++) if (!strcmp(buf, c->c_name)) return (c->c_val); return (-1); } /* * fork off and become a daemon, but wait for the child to come online * before returing to the parent, or we get disk thrashing at boot etc. * Set a timer so we don't hang forever if it wedges. */ int waitdaemon(nochdir, noclose, maxwait) int nochdir, noclose, maxwait; { int fd; int status; pid_t pid, childpid; switch (childpid = fork()) { case -1: return (-1); case 0: break; default: signal(SIGALRM, timedout); alarm(maxwait); while ((pid = wait3(&status, 0, NULL)) != -1) { if (WIFEXITED(status)) errx(1, "child pid %d exited with return code %d", pid, WEXITSTATUS(status)); if (WIFSIGNALED(status)) errx(1, "child pid %d exited on signal %d%s", pid, WTERMSIG(status), WCOREDUMP(status) ? " (core dumped)" : ""); if (pid == childpid) /* it's gone... */ break; } exit(0); } if (setsid() == -1) return (-1); if (!nochdir) (void)chdir("/"); if (!noclose && (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { (void)dup2(fd, STDIN_FILENO); (void)dup2(fd, STDOUT_FILENO); (void)dup2(fd, STDERR_FILENO); if (fd > 2) (void)close (fd); } return (getppid()); } /* * We get a SIGALRM from the child when it's running and finished doing it's * fsync()'s or O_SYNC writes for all the boot messages. * * We also get a signal from the kernel if the timer expires, so check to * see what happened. */ void timedout(sig) int sig __unused; { int left; left = alarm(0); signal(SIGALRM, SIG_DFL); if (left == 0) errx(1, "timed out waiting for child"); else exit(0); } /* * Add `s' to the list of allowable peer addresses to accept messages * from. * * `s' is a string in the form: * * [*]domainname[:{servicename|portnumber|*}] * * or * * netaddr/maskbits[:{servicename|portnumber|*}] * * Returns -1 on error, 0 if the argument was valid. */ int allowaddr(s) char *s; { char *cp1, *cp2; struct allowedpeer ap; struct servent *se; regex_t re; int i; if ((cp1 = strrchr(s, ':'))) { /* service/port provided */ *cp1++ = '\0'; if (strlen(cp1) == 1 && *cp1 == '*') /* any port allowed */ ap.port = htons(0); else if ((se = getservbyname(cp1, "udp"))) ap.port = se->s_port; else { ap.port = htons((int)strtol(cp1, &cp2, 0)); if (*cp2 != '\0') return -1; /* port not numeric */ } } else { if ((se = getservbyname("syslog", "udp"))) ap.port = se->s_port; else /* sanity, should not happen */ ap.port = htons(514); } /* the regexp's are ugly, but the cleanest way */ if (regcomp(&re, "^[0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+(/[0-9]+)?$", REG_EXTENDED)) /* if RE compilation fails, that's an internal error */ abort(); if (regexec(&re, s, 0, 0, 0) == 0) { /* arg `s' is numeric */ ap.isnumeric = 1; if ((cp1 = strchr(s, '/')) != NULL) { *cp1++ = '\0'; i = atoi(cp1); if (i < 0 || i > 32) return -1; /* convert masklen to netmask */ ap.a_mask.s_addr = htonl(~((1 << (32 - i)) - 1)); } if (ascii2addr(AF_INET, s, &ap.a_addr) == -1) return -1; if (cp1 == NULL) { /* use default netmask */ if (IN_CLASSA(ntohl(ap.a_addr.s_addr))) ap.a_mask.s_addr = htonl(IN_CLASSA_NET); else if (IN_CLASSB(ntohl(ap.a_addr.s_addr))) ap.a_mask.s_addr = htonl(IN_CLASSB_NET); else ap.a_mask.s_addr = htonl(IN_CLASSC_NET); } } else { /* arg `s' is domain name */ ap.isnumeric = 0; ap.a_name = s; } regfree(&re); if (Debug) { printf("allowaddr: rule %d: ", NumAllowed); if (ap.isnumeric) { printf("numeric, "); printf("addr = %s, ", addr2ascii(AF_INET, &ap.a_addr, sizeof(struct in_addr), 0)); printf("mask = %s; ", addr2ascii(AF_INET, &ap.a_mask, sizeof(struct in_addr), 0)); } else printf("domainname = %s; ", ap.a_name); printf("port = %d\n", ntohs(ap.port)); } if ((AllowedPeers = realloc(AllowedPeers, ++NumAllowed * sizeof(struct allowedpeer))) == NULL) { fprintf(stderr, "Out of memory!\n"); exit(EX_OSERR); } memcpy(&AllowedPeers[NumAllowed - 1], &ap, sizeof(struct allowedpeer)); return 0; } /* * Validate that the remote peer has permission to log to us. */ int validate(sin, hname) struct sockaddr_in *sin; const char *hname; { int i; size_t l1, l2; char *cp, name[MAXHOSTNAMELEN]; struct allowedpeer *ap; if (NumAllowed == 0) /* traditional behaviour, allow everything */ return 1; strlcpy(name, hname, sizeof name); if (strchr(name, '.') == NULL) { strlcat(name, ".", sizeof name); strlcat(name, LocalDomain, sizeof name); } dprintf("validate: dgram from IP %s, port %d, name %s;\n", addr2ascii(AF_INET, &sin->sin_addr, sizeof(struct in_addr), 0), ntohs(sin->sin_port), name); /* now, walk down the list */ for (i = 0, ap = AllowedPeers; i < NumAllowed; i++, ap++) { if (ntohs(ap->port) != 0 && ap->port != sin->sin_port) { dprintf("rejected in rule %d due to port mismatch.\n", i); continue; } if (ap->isnumeric) { if ((sin->sin_addr.s_addr & ap->a_mask.s_addr) != ap->a_addr.s_addr) { dprintf("rejected in rule %d due to IP mismatch.\n", i); continue; } } else { cp = ap->a_name; l1 = strlen(name); if (*cp == '*') { /* allow wildmatch */ cp++; l2 = strlen(cp); if (l2 > l1 || memcmp(cp, &name[l1 - l2], l2) != 0) { dprintf("rejected in rule %d due to name mismatch.\n", i); continue; } } else { /* exact match */ l2 = strlen(cp); if (l2 != l1 || memcmp(cp, name, l1) != 0) { dprintf("rejected in rule %d due to name mismatch.\n", i); continue; } } } dprintf("accepted in rule %d.\n", i); return 1; /* hooray! */ } return 0; } /* * Fairly similar to popen(3), but returns an open descriptor, as * opposed to a FILE *. */ int p_open(prog, pid) char *prog; pid_t *pid; { int pfd[2], nulldesc, i; sigset_t omask, mask; char *argv[4]; /* sh -c cmd NULL */ char errmsg[200]; if (pipe(pfd) == -1) return -1; if ((nulldesc = open(_PATH_DEVNULL, O_RDWR)) == -1) /* we are royally screwed anyway */ return -1; sigemptyset(&mask); sigaddset(&mask, SIGALRM); sigaddset(&mask, SIGHUP); sigprocmask(SIG_BLOCK, &mask, &omask); switch ((*pid = fork())) { case -1: sigprocmask(SIG_SETMASK, &omask, 0); close(nulldesc); return -1; case 0: argv[0] = "sh"; argv[1] = "-c"; argv[2] = prog; argv[3] = NULL; alarm(0); (void)setsid(); /* Avoid catching SIGHUPs. */ /* * Throw away pending signals, and reset signal * behaviour to standard values. */ signal(SIGALRM, SIG_IGN); signal(SIGHUP, SIG_IGN); sigprocmask(SIG_SETMASK, &omask, 0); signal(SIGPIPE, SIG_DFL); signal(SIGQUIT, SIG_DFL); signal(SIGALRM, SIG_DFL); signal(SIGHUP, SIG_DFL); dup2(pfd[0], STDIN_FILENO); dup2(nulldesc, STDOUT_FILENO); dup2(nulldesc, STDERR_FILENO); for (i = getdtablesize(); i > 2; i--) (void) close(i); (void) execvp(_PATH_BSHELL, argv); _exit(255); } sigprocmask(SIG_SETMASK, &omask, 0); close(nulldesc); close(pfd[0]); /* * Avoid blocking on a hung pipe. With O_NONBLOCK, we are * supposed to get an EWOULDBLOCK on writev(2), which is * caught by the logic above anyway, which will in turn close * the pipe, and fork a new logging subprocess if necessary. * The stale subprocess will be killed some time later unless * it terminated itself due to closing its input pipe (so we * get rid of really dead puppies). */ if (fcntl(pfd[1], F_SETFL, O_NONBLOCK) == -1) { /* This is bad. */ (void)snprintf(errmsg, sizeof errmsg, "Warning: cannot change pipe to PID %d to " "non-blocking behaviour.", (int)*pid); logerror(errmsg); } return pfd[1]; } void deadq_enter(pid, name) pid_t pid; const char *name; { dq_t p; int status; /* * Be paranoid, if we can't signal the process, don't enter it * into the dead queue (perhaps it's already dead). If possible, * we try to fetch and log the child's status. */ if (kill(pid, 0) != 0) { if (waitpid(pid, &status, WNOHANG) > 0) log_deadchild(pid, status, name); return; } p = malloc(sizeof(struct deadq_entry)); if (p == 0) { errno = 0; logerror("panic: out of virtual memory!"); exit(1); } p->dq_pid = pid; p->dq_timeout = DQ_TIMO_INIT; TAILQ_INSERT_TAIL(&deadq_head, p, dq_entries); } int deadq_remove(pid) pid_t pid; { dq_t q; for (q = TAILQ_FIRST(&deadq_head); q != NULL; q = TAILQ_NEXT(q, dq_entries)) if (q->dq_pid == pid) { TAILQ_REMOVE(&deadq_head, q, dq_entries); free(q); return 1; } return 0; } void log_deadchild(pid, status, name) pid_t pid; int status; const char *name; { int code; char buf[256]; const char *reason; errno = 0; /* Keep strerror() stuff out of logerror messages. */ if (WIFSIGNALED(status)) { reason = "due to signal"; code = WTERMSIG(status); } else { reason = "with status"; code = WEXITSTATUS(status); if (code == 0) return; } (void)snprintf(buf, sizeof buf, "Logging subprocess %d (%s) exited %s %d.", pid, name, reason, code); logerror(buf); }