/* $OpenBSD: syslogd.c,v 1.82 2004/07/03 23:40:44 djm Exp $ */ /* * 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. 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 const char sccsid[] = "@(#)syslogd.c 8.3 (Berkeley) 4/4/94"; #else static const char rcsid[] = "$OpenBSD: syslogd.c,v 1.82 2004/07/03 23:40:44 djm Exp $"; #endif #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 maximum 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) * memory buffer logging by Damien Miller */ #define MAXLINE 1024 /* maximum line length */ #define MIN_MEMBUF (MAXLINE * 4) /* Minimum memory buffer size */ #define MAX_MEMBUF (256 * 1024) /* Maximum memory buffer size */ #define MAX_MEMBUF_NAME 64 /* Max length of membuf log name */ #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 /* timeout 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 #define SYSLOG_NAMES #include #include "syslogd.h" char *ConfFile = _PATH_LOGCONF; const char ctty[] = _PATH_CONSOLE; #define MAXUNAMES 20 /* maximum number of user names */ /* * 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 */ /* * 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 */ u_char f_pmask[LOG_NFACILITIES+1]; /* priority mask */ char *f_program; /* program this applies to */ union { char f_uname[MAXUNAMES][UT_NAMESIZE+1]; struct { char f_hname[MAXHOSTNAMELEN]; struct sockaddr_storage f_addr; } f_forw; /* forwarding address */ char f_fname[MAXPATHLEN]; struct { char f_mname[MAX_MEMBUF_NAME]; struct ringbuf *f_rb; int f_overflow; } f_mb; /* Memory buffer */ } f_un; char f_prevline[MAXSVLINE]; /* last message logged */ char f_lasttime[16]; /* time of last occurrence */ char f_prevhost[MAXHOSTNAMELEN]; /* 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 */ unsigned int f_repeatcount; /* number of "repeated" msgs */ int f_quick; /* abort when matched */ }; /* * 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_MEMBUF 7 /* memory buffer */ char *TypeNames[8] = { "UNUSED", "FILE", "TTY", "CONSOLE", "FORW", "USERS", "WALL", "MEMBUF" }; struct filed *Files; struct filed consfile; int nfunix = 1; /* Number of Unix domain sockets requested */ char *funixn[MAXFUNIX] = { _PATH_LOG }; /* Paths to Unix domain sockets */ int Debug; /* debug flag */ int Startup = 1; /* startup flag */ char LocalHostName[MAXHOSTNAMELEN]; /* our hostname */ char *LocalDomain; /* our local domain name */ int InetInuse = 0; /* non-zero if INET sockets are being used */ 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 = 1; /* when true, speak only unix domain socks */ int NoDNS = 0; /* when true, will refrain from doing DNS lookups */ char *ctlsock_path = NULL; /* Path to control socket */ #define CTL_READING_CMD 1 #define CTL_WRITING_REPLY 2 int ctl_state = 0; /* What the control socket is up to */ /* * Client protocol NB. all numeric fields in network byte order */ #define CTL_VERSION 0 /* Request */ struct { u_int32_t version; #define CMD_READ 1 /* Read out log */ #define CMD_READ_CLEAR 2 /* Read and clear log */ #define CMD_CLEAR 3 /* Clear log */ #define CMD_LIST 4 /* List available logs */ #define CMD_FLAGS 5 /* Query flags only */ u_int32_t cmd; char logname[MAX_MEMBUF_NAME]; } ctl_cmd; size_t ctl_cmd_bytes = 0; /* number of bytes of ctl_cmd read */ /* Reply */ struct ctl_reply_hdr { u_int32_t version; #define CTL_HDR_FLAG_OVERFLOW 0x01 u_int32_t flags; /* Reply text follows, up to MAX_MEMBUF long */ }; #define CTL_HDR_LEN (sizeof(struct ctl_reply_hdr)) #define CTL_REPLY_MAXSIZE (CTL_HDR_LEN + MAX_MEMBUF) char *ctl_reply = NULL; /* Buffer for control connection reply */ size_t ctl_reply_size = 0; /* Number of bytes used in reply */ size_t ctl_reply_offset = 0; /* Number of bytes of reply written so far */ struct pollfd pfd[N_PFD]; volatile sig_atomic_t MarkSet; volatile sig_atomic_t WantDie; volatile sig_atomic_t DoInit; void cfline(char *, struct filed *, char *); void cvthname(struct sockaddr_in *, char *, size_t); int decode(const char *, const CODE *); void dodie(int); void doinit(int); void die(int); void domark(int); void markit(void); void fprintlog(struct filed *, int, char *); void init(void); void logerror(const char *); void logmsg(int, char *, char *, int); void printline(char *, char *); void printsys(char *); void reapchild(int); char *ttymsg(struct iovec *, int, char *, int); void usage(void); void wallmsg(struct filed *, struct iovec *); int getmsgbufsize(void); int unix_socket(char *, int, mode_t); void double_rbuf(int); void ctlsock_accept_handler(void); void ctlconn_read_handler(void); void ctlconn_write_handler(void); int main(int argc, char *argv[]) { int ch, i, linesize, fd; struct sockaddr_un fromunix; struct sockaddr_in s_in, frominet; socklen_t len; char *p, *line; char resolve[MAXHOSTNAMELEN]; int lockpipe[2], nullfd = -1; FILE *fp; while ((ch = getopt(argc, argv, "dnuf:m:p:a:s:")) != -1) switch (ch) { case 'd': /* debug */ Debug++; break; case 'f': /* configuration file */ ConfFile = optarg; break; case 'm': /* mark interval */ MarkInterval = atoi(optarg) * 60; break; case 'n': /* don't do DNS lookups */ NoDNS = 1; break; case 'p': /* path */ funixn[0] = optarg; break; case 'u': /* allow udp input port */ SecureMode = 0; break; case 'a': if (nfunix >= MAXFUNIX) fprintf(stderr, "syslogd: " "out of descriptors, ignoring %s\n", optarg); else funixn[nfunix++] = optarg; break; case 's': ctlsock_path = optarg; break; default: usage(); } if ((argc -= optind) != 0) usage(); if (Debug) setlinebuf(stdout); consfile.f_type = F_CONSOLE; (void)strlcpy(consfile.f_un.f_fname, ctty, sizeof(consfile.f_un.f_fname)); (void)gethostname(LocalHostName, sizeof(LocalHostName)); if ((p = strchr(LocalHostName, '.')) != NULL) { *p++ = '\0'; LocalDomain = p; } else LocalDomain = ""; linesize = getmsgbufsize(); if (linesize < MAXLINE) linesize = MAXLINE; linesize++; if ((line = malloc(linesize)) == NULL) { logerror("Couldn't allocate line buffer"); die(0); } /* Clear poll array, set all fds to ignore */ for (i = 0; i < N_PFD; i++) { pfd[i].fd = -1; pfd[i].events = 0; } if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) != -1) { struct servent *sp; /* XXX use getaddrinfo */ sp = getservbyname("syslog", "udp"); if (sp == NULL) { errno = 0; logerror("syslog/udp: unknown service"); die(0); } memset(&s_in, 0, sizeof(s_in)); s_in.sin_len = sizeof(s_in); s_in.sin_family = AF_INET; s_in.sin_port = LogPort = sp->s_port; if (bind(fd, (struct sockaddr *)&s_in, sizeof(s_in)) < 0) { logerror("bind"); if (!Debug) die(0); } else { InetInuse = 1; double_rbuf(fd); pfd[PFD_INET].fd = fd; pfd[PFD_INET].events = POLLIN; } } #ifndef SUN_LEN #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2) #endif for (i = 0; i < nfunix; i++) { if ((fd = unix_socket(funixn[i], SOCK_DGRAM, 0666)) == -1) { if (i == 0 && !Debug) die(0); continue; } double_rbuf(fd); pfd[PFD_UNIX_0 + i].fd = fd; pfd[PFD_UNIX_0 + i].events = POLLIN; } if (ctlsock_path != NULL) { fd = unix_socket(ctlsock_path, SOCK_STREAM, 0600); if (fd != -1) { if (listen(fd, 16) == -1) { logerror("ctlsock listen"); die(0); } pfd[PFD_CTLSOCK].fd = fd; pfd[PFD_CTLSOCK].events = POLLIN; } else if (!Debug) die(0); } if ((fd = open(_PATH_KLOG, O_RDONLY, 0)) == -1) { dprintf("can't open %s (%d)\n", _PATH_KLOG, errno); } else { pfd[PFD_KLOG].fd = fd; pfd[PFD_KLOG].events = POLLIN; } dprintf("off & running....\n"); chdir("/"); tzset(); if (!Debug) { char c; pipe(lockpipe); switch(fork()) { case -1: exit(1); case 0: setsid(); nullfd = open(_PATH_DEVNULL, O_RDWR); close(lockpipe[0]); break; default: close(lockpipe[1]); read(lockpipe[0], &c, 1); _exit(0); } } /* tuck my process id away */ if (!Debug) { fp = fopen(_PATH_LOGPID, "w"); if (fp != NULL) { fprintf(fp, "%ld\n", (long)getpid()); (void) fclose(fp); } } /* Privilege separation begins here */ if (priv_init(ConfFile, NoDNS, lockpipe[1], nullfd, argv) < 0) errx(1, "unable to privsep"); /* Process is now unprivileged and inside a chroot */ init(); Startup = 0; /* Allocate ctl socket reply buffer if we have a ctl socket */ if (pfd[PFD_CTLSOCK].fd != -1 && (ctl_reply = malloc(CTL_REPLY_MAXSIZE)) == NULL) { logerror("Couldn't allocate ctlsock reply buffer"); die(0); } if (!Debug) { dup2(nullfd, STDIN_FILENO); dup2(nullfd, STDOUT_FILENO); dup2(nullfd, STDERR_FILENO); if (nullfd > 2) close(nullfd); close(lockpipe[1]); } /* * Signal to the priv process that the initial config parsing is done * so that it will reject any future attempts to open more files */ priv_config_parse_done(); (void)signal(SIGHUP, doinit); (void)signal(SIGTERM, dodie); (void)signal(SIGINT, Debug ? dodie : SIG_IGN); (void)signal(SIGQUIT, Debug ? dodie : SIG_IGN); (void)signal(SIGCHLD, reapchild); (void)signal(SIGALRM, domark); (void)signal(SIGPIPE, SIG_IGN); (void)alarm(TIMERINTVL); for (;;) { if (MarkSet) markit(); if (WantDie) die(WantDie); if (DoInit) { init(); DoInit = 0; } switch (poll(pfd, PFD_UNIX_0 + nfunix, -1)) { case 0: continue; case -1: if (errno != EINTR) logerror("poll"); continue; } if ((pfd[PFD_KLOG].revents & POLLIN) != 0) { i = read(pfd[PFD_KLOG].fd, line, linesize - 1); if (i > 0) { line[i] = '\0'; printsys(line); } else if (i < 0 && errno != EINTR) { logerror("klog"); pfd[PFD_KLOG].fd = -1; pfd[PFD_KLOG].events = 0; } } if ((pfd[PFD_INET].revents & POLLIN) != 0) { len = sizeof(frominet); i = recvfrom(pfd[PFD_INET].fd, line, MAXLINE, 0, (struct sockaddr *)&frominet, &len); if (SecureMode) { /* silently drop it */ } else { if (i > 0) { line[i] = '\0'; cvthname(&frominet, resolve, sizeof resolve); dprintf("cvthname res: %s\n", resolve); printline(resolve, line); } else if (i < 0 && errno != EINTR) logerror("recvfrom inet"); } } if ((pfd[PFD_CTLSOCK].revents & POLLIN) != 0) ctlsock_accept_handler(); if ((pfd[PFD_CTLCONN].revents & POLLIN) != 0) ctlconn_read_handler(); if ((pfd[PFD_CTLCONN].revents & POLLOUT) != 0) ctlconn_write_handler(); for (i = 0; i < nfunix; i++) { if ((pfd[PFD_UNIX_0 + i].revents & POLLIN) != 0) { len = sizeof(fromunix); len = recvfrom(pfd[PFD_UNIX_0 + i].fd, line, MAXLINE, 0, (struct sockaddr *)&fromunix, &len); if (len > 0) { line[len] = '\0'; printline(LocalHostName, line); } else if (len < 0 && errno != EINTR) logerror("recvfrom unix"); } } } /* NOTREACHED */ free(pfd); return (0); } void usage(void) { (void)fprintf(stderr, "usage: syslogd [-dnu] [-a path] [-f config_file] [-m mark_interval]\n" " [-p log_socket] [-s reporting_socket]\n"); exit(1); } /* * Take a raw input line, decode the message, and print the message * on the appropriate log files. */ void printline(char *hname, char *msg) { int 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. * NOTE: since LOG_KERN == 0 this will also match * messages with no facility specified. */ if (LOG_FAC(pri) == LOG_KERN) pri = LOG_USER | LOG_PRI(pri); for (q = line; *p && q < &line[sizeof(line) - 4]; p++) { if (*p == '\n') *q++ = ' '; else q = vis(q, *p, 0, 0); } *q = '\0'; logmsg(pri, line, hname, 0); } /* * Take a raw input line from /dev/klog, split and format similar to syslog(). */ void printsys(char *msg) { int c, pri, flags; char *lp, *p, *q, line[MAXLINE + 1]; (void)snprintf(line, sizeof line, "%s: ", _PATH_UNIX); lp = line + strlen(line); for (p = msg; *p != '\0'; ) { flags = SYNC_FILE | ADDDATE; /* fsync file 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; q = lp; while (*p && (c = *p++) != '\n' && q < &line[sizeof(line) - 4]) q = vis(q, c, 0, 0); logmsg(pri, line, LocalHostName, flags); } } time_t now; /* * Log a message to the appropriate log files, users, etc. based on * the priority. */ void logmsg(int pri, char *msg, char *from, int flags) { struct filed *f; int fac, msglen, prilev, i; sigset_t mask, omask; char *timestamp; char prog[NAME_MAX+1]; dprintf("logmsg: pri 0%o, flags 0x%x, from %s, msg %s\n", pri, flags, from, msg); sigemptyset(&mask); sigaddset(&mask, SIGALRM); sigaddset(&mask, SIGHUP); sigprocmask(SIG_BLOCK, &mask, &omask); /* * 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; } /* 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]) && msg[i] != '-') break; prog[i] = msg[i]; } prog[i] = 0; /* log the message to the particular outputs */ if (!Initialized) { f = &consfile; f->f_file = priv_open_tty(ctty); if (f->f_file >= 0) { fprintlog(f, flags, msg); (void)close(f->f_file); f->f_file = -1; } (void)sigprocmask(SIG_SETMASK, &omask, NULL); return; } for (f = Files; f; f = f->f_next) { /* skip messages that are incorrect priority */ if (f->f_pmask[fac] < prilev || f->f_pmask[fac] == INTERNAL_NOPRI) continue; /* 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) && !strcmp(from, f->f_prevhost)) { strlcpy(f->f_lasttime, timestamp, 16); 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; strlcpy(f->f_lasttime, timestamp, 16); strlcpy(f->f_prevhost, from, sizeof(f->f_prevhost)); if (msglen < MAXSVLINE) { f->f_prevlen = msglen; strlcpy(f->f_prevline, msg, sizeof(f->f_prevline)); fprintlog(f, flags, (char *)NULL); } else { f->f_prevline[0] = 0; f->f_prevlen = 0; fprintlog(f, flags, msg); } } if (f->f_quick) break; } (void)sigprocmask(SIG_SETMASK, &omask, NULL); } void fprintlog(struct filed *f, int flags, char *msg) { struct iovec iov[6]; struct iovec *v; int l; char line[MAXLINE + 1], repbuf[80], greetings[500]; v = iov; if (f->f_type == F_WALL) { if ((l = snprintf(greetings, sizeof(greetings), "\r\n\7Message from syslogd@%s at %.24s ...\r\n", f->f_prevhost, ctime(&now))) >= sizeof(greetings) || l == -1) l = strlen(greetings); v->iov_base = greetings; v->iov_len = l; 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++; } 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) { if ((l = snprintf(repbuf, sizeof(repbuf), "last message repeated %d times", f->f_prevcount)) >= sizeof(repbuf) || l == -1) l = strlen(repbuf); v->iov_base = repbuf; v->iov_len = l; } 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); if ((l = snprintf(line, sizeof(line), "<%d>%.15s %s", f->f_prevpri, (char *)iov[0].iov_base, (char *)iov[4].iov_base)) >= sizeof(line) || l == -1) l = strlen(line); if (sendto(pfd[PFD_INET].fd, line, l, 0, (struct sockaddr *)&f->f_un.f_forw.f_addr, f->f_un.f_forw.f_addr.ss_len) != l) { f->f_type = F_UNUSED; logerror("sendto"); } break; case F_CONSOLE: if (flags & IGN_CONS) { dprintf(" (ignored)\n"); break; } /* FALLTHROUGH */ case F_TTY: case F_FILE: dprintf(" %s\n", f->f_un.f_fname); if (f->f_type != F_FILE) { v->iov_base = "\r\n"; v->iov_len = 2; } else { v->iov_base = "\n"; v->iov_len = 1; } again: if (writev(f->f_file, iov, 6) < 0) { int e = errno; (void)close(f->f_file); /* * Check for errors on TTY's due to loss of tty */ if (e == EAGAIN) { /* * Silently drop messages on blocked write. * This can happen when logging to a locked tty. */ break; } else if ((e == EIO || e == EBADF) && f->f_type != F_FILE) { f->f_file = priv_open_tty(f->f_un.f_fname); if (f->f_file < 0) { f->f_type = F_UNUSED; logerror(f->f_un.f_fname); } else goto again; } else { f->f_type = F_UNUSED; f->f_file = -1; errno = e; logerror(f->f_un.f_fname); } } else if (flags & SYNC_FILE) (void)fsync(f->f_file); break; case F_USERS: case F_WALL: dprintf("\n"); v->iov_base = "\r\n"; v->iov_len = 2; wallmsg(f, iov); break; case F_MEMBUF: dprintf("\n"); snprintf(line, sizeof(line), "%.15s %s %s", (char *)iov[0].iov_base, (char *)iov[2].iov_base, (char *)iov[4].iov_base); if (ringbuf_append_line(f->f_un.f_mb.f_rb, line) == 1) f->f_un.f_mb.f_overflow = 1; 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(struct filed *f, struct iovec *iov) { struct utmp ut; char line[sizeof(ut.ut_line) + 1], *p; static int reenter; /* avoid calling ourselves */ FILE *uf; int i; if (reenter++) return; if ((uf = priv_open_utmp()) == NULL) { logerror(_PATH_UTMP); reenter = 0; return; } /* NOSTRICT */ while (fread((char *)&ut, sizeof(ut), 1, uf) == 1) { if (ut.ut_name[0] == '\0') continue; /* must use strncpy since ut_* may not be NUL terminated */ strncpy(line, ut.ut_line, sizeof(line) - 1); line[sizeof(line) - 1] = '\0'; if (f->f_type == F_WALL) { if ((p = ttymsg(iov, 6, 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, 6, line, TTYMSGTIME)) != NULL) { errno = 0; /* already in msg */ logerror(p); } break; } } } (void)fclose(uf); reenter = 0; } void reapchild(int signo) { int save_errno = errno; int status; while (waitpid(-1, &status, WNOHANG) > 0) ; errno = save_errno; } /* * Return a printable representation of a host address. */ void cvthname(struct sockaddr_in *f, char *result, size_t res_len) { sigset_t omask, nmask; char *p, *ip; int ret_len; if (f->sin_family != AF_INET) { dprintf("Malformed from address\n"); strlcpy(result, "???", res_len); return; } ip = inet_ntoa(f->sin_addr); dprintf("cvthname(%s)\n", ip); if (NoDNS) { strlcpy(result, ip, res_len); return; } sigemptyset(&nmask); sigaddset(&nmask, SIGHUP); sigprocmask(SIG_BLOCK, &nmask, &omask); ret_len = priv_gethostbyaddr((char *)&f->sin_addr, sizeof(struct in_addr), f->sin_family, result, res_len); sigprocmask(SIG_SETMASK, &omask, NULL); if (ret_len == 0) { dprintf("Host name for your address (%s) unknown\n", ip); strlcpy(result, ip, res_len); } else if ((p = strchr(result, '.')) && strcmp(p + 1, LocalDomain) == 0) *p = '\0'; } void dodie(int signo) { WantDie = signo; } void domark(int signo) { MarkSet = 1; } void doinit(int signo) { DoInit = 1; } /* * Print syslogd errors some place. */ void logerror(const char *type) { char buf[100]; 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); if (Startup) fprintf(stderr, "%s\n", buf); else logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE); } void die(int signo) { struct filed *f; int was_initialized = Initialized; char buf[100]; Initialized = 0; /* Don't log SIGCHLDs */ alarm(0); for (f = Files; f != NULL; f = f->f_next) { /* flush any pending output */ if (f->f_prevcount) fprintlog(f, 0, (char *)NULL); } Initialized = was_initialized; if (signo) { dprintf("syslogd: exiting on signal %d\n", signo); (void)snprintf(buf, sizeof buf, "exiting on signal %d", signo); errno = 0; logerror(buf); } dprintf("[unpriv] syslogd child about to exit\n"); exit(0); } /* * INIT -- Initialize syslogd from configuration table */ void init(void) { char cline[LINE_MAX], prog[NAME_MAX+1], *p; struct filed *f, *next, **nextp; FILE *cf; int i; dprintf("init\n"); /* If config file has been modified, then just die to restart */ if (priv_config_modified()) { dprintf("config file changed: dying\n"); die(0); } /* * 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_TTY: case F_CONSOLE: (void)close(f->f_file); break; case F_FORW: break; } next = f->f_next; if (f->f_program) free(f->f_program); free((char *)f); } Files = NULL; nextp = &Files; /* open the configuration file */ if ((cf = priv_open_config()) == 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; strlcpy(prog, "*", sizeof(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: the following lines apply only to that program. */ for (p = cline; isspace(*p); ++p) continue; if (*p == '\0' || *p == '#') continue; if (*p == '!') { p++; while (isspace(*p)) p++; if (!*p || (*p == '*' && (!p[1] || isspace(p[1])))) { strlcpy(prog, "*", sizeof(prog)); continue; } for (i = 0; i < NAME_MAX; i++) { if (!isalnum(p[i]) && p[i] != '-' && p[i] != '!') break; prog[i] = p[i]; } prog[i] = 0; continue; } p = cline + strlen(cline); while (p > cline) if (!isspace(*--p)) { p++; break; } *p = '\0'; f = (struct filed *)calloc(1, sizeof(*f)); *nextp = f; nextp = &f->f_next; cfline(cline, f, prog); } /* 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: case F_TTY: case F_CONSOLE: printf("%s", f->f_un.f_fname); break; case F_FORW: printf("%s", f->f_un.f_forw.f_hname); 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; case F_MEMBUF: printf("%s", f->f_un.f_mb.f_mname); 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(char *line, struct filed *f, char *prog) { int i, pri, addr_len; size_t rb_len; char *bp, *p, *q, *cp; char buf[MAXLINE], ebuf[100]; struct filed *xf; dprintf("cfline(\"%s\", f, \"%s\")\n", line, prog); 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 program name if any */ if (*prog == '!') { f->f_quick = 1; prog++; } else f->f_quick = 0; if (!strcmp(prog, "*")) prog = NULL; else { f->f_program = calloc(1, strlen(prog)+1); if (f->f_program) strlcpy(f->f_program, prog, strlen(prog)+1); } /* scan through the list of selectors */ for (p = line; *p && *p != '\t';) { /* find the end of this facility name list */ for (q = p; *q && *q != '\t' && *q++ != '.'; ) continue; /* 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 { /* ignore trailing spaces */ for (i=strlen(buf)-1; i >= 0 && buf[i] == ' '; i--) { buf[i]='\0'; } 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; 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; } while (*p == ',' || *p == ' ') p++; } p = q; } /* skip to action part */ while (*p == '\t') p++; switch (*p) { case '@': if (!InetInuse) break; if ((cp = strrchr(++p, ':')) != NULL) *cp++ = '\0'; if ((strlcpy(f->f_un.f_forw.f_hname, p, sizeof(f->f_un.f_forw.f_hname)) >= sizeof(f->f_un.f_forw.f_hname))) { snprintf(ebuf, sizeof(ebuf), "hostname too long \"%s\"", p); logerror(ebuf); break; } addr_len = priv_gethostserv(f->f_un.f_forw.f_hname, cp == NULL ? "syslog" : cp, (struct sockaddr*)&f->f_un.f_forw.f_addr, sizeof(f->f_un.f_forw.f_addr)); if (addr_len < 1) { snprintf(ebuf, sizeof(ebuf), "bad hostname \"%s\"", p); logerror(ebuf); break; } f->f_type = F_FORW; break; case '/': (void)strlcpy(f->f_un.f_fname, p, sizeof(f->f_un.f_fname)); if (strcmp(p, ctty) == 0) f->f_file = priv_open_tty(p); else f->f_file = priv_open_log(p); if (f->f_file < 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; } else { f->f_type = F_FILE; /* Clear O_NONBLOCK flag on f->f_file */ if ((i = fcntl(f->f_file, F_GETFL, 0)) != -1) { i &= ~O_NONBLOCK; fcntl(f->f_file, F_SETFL, i); } } break; case '*': f->f_type = F_WALL; break; case ':': f->f_type = F_MEMBUF; /* Parse buffer size (in kb) */ errno = 0; rb_len = strtoul(++p, &q, 0); if (*p == '\0' || (errno == ERANGE && rb_len == ULONG_MAX) || *q != ':' || rb_len == 0) { f->f_type = F_UNUSED; logerror(p); break; } q++; rb_len *= 1024; /* Copy buffer name */ for(i = 0; i < sizeof(f->f_un.f_mb.f_mname) - 1; i++) { if (!isalnum(q[i])) break; f->f_un.f_mb.f_mname[i] = q[i]; } /* Make sure buffer name is unique */ for (xf = Files; i != 0 && xf != f; xf = xf->f_next) { if (xf->f_type == F_MEMBUF && strcmp(xf->f_un.f_mb.f_mname, f->f_un.f_mb.f_mname) == 0) break; } /* Error on missing or non-unique name, or bad buffer length */ if (i == 0 || rb_len > MAX_MEMBUF || xf != f) { f->f_type = F_UNUSED; logerror(p); break; } /* Allocate buffer */ rb_len = MAX(rb_len, MIN_MEMBUF); if ((f->f_un.f_mb.f_rb = ringbuf_init(rb_len)) == NULL) { f->f_type = F_UNUSED; logerror(p); break; } f->f_un.f_mb.f_overflow = 0; 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; } } /* * Retrieve the size of the kernel message buffer, via sysctl. */ int getmsgbufsize(void) { int msgbufsize, mib[2]; size_t size; mib[0] = CTL_KERN; mib[1] = KERN_MSGBUFSIZE; size = sizeof msgbufsize; if (sysctl(mib, 2, &msgbufsize, &size, NULL, 0) == -1) { dprintf("couldn't get kern.msgbufsize\n"); return (0); } return (msgbufsize); } /* * Decode a symbolic name to a numeric value */ int decode(const char *name, const CODE *codetab) { const 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); } void markit(void) { struct filed *f; 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); } } MarkSet = 0; (void)alarm(TIMERINTVL); } int unix_socket(char *path, int type, mode_t mode) { struct sockaddr_un s_un; char errbuf[512]; int fd; mode_t old_umask; memset(&s_un, 0, sizeof(s_un)); s_un.sun_family = AF_UNIX; if (strlcpy(s_un.sun_path, path, sizeof(s_un.sun_path)) > sizeof(s_un.sun_path)) { snprintf(errbuf, sizeof(errbuf), "socket path too long: %s", path); logerror(errbuf); die(0); } if ((fd = socket(AF_UNIX, type, 0)) == -1) { logerror("socket"); return (-1); } if (Debug) { if (connect(fd, (struct sockaddr *)&s_un, sizeof(s_un)) == 0 || errno == EPROTOTYPE) { close(fd); errno = EISCONN; logerror("connect"); return (-1); } } old_umask = umask(0177); unlink(path); if (bind(fd, (struct sockaddr *)&s_un, SUN_LEN(&s_un)) == -1) { snprintf(errbuf, sizeof(errbuf), "cannot bind %s", path); logerror(errbuf); umask(old_umask); close(fd); return (-1); } umask(old_umask); if (chmod(path, mode) == -1) { snprintf(errbuf, sizeof(errbuf), "cannot chmod %s", path); logerror(errbuf); close(fd); unlink(path); return (-1); } return (fd); } void double_rbuf(int fd) { socklen_t slen, len; if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len, &slen) == 0) { len *= 2; setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len, slen); } } static void ctlconn_cleanup(void) { if (pfd[PFD_CTLCONN].fd != -1) close(pfd[PFD_CTLCONN].fd); pfd[PFD_CTLCONN].fd = -1; pfd[PFD_CTLCONN].events = pfd[PFD_CTLCONN].revents = 0; pfd[PFD_CTLSOCK].events = POLLIN; ctl_state = ctl_cmd_bytes = ctl_reply_offset = ctl_reply_size = 0; } void ctlsock_accept_handler(void) { int fd, flags; dprintf("Accepting control connection\n"); fd = accept(pfd[PFD_CTLSOCK].fd, NULL, NULL); if (fd == -1) { if (errno != EINTR && errno != ECONNABORTED) logerror("accept ctlsock"); return; } ctlconn_cleanup(); /* Only one connection at a time */ pfd[PFD_CTLSOCK].events = pfd[PFD_CTLSOCK].revents = 0; if ((flags = fcntl(fd, F_GETFL)) == -1 || fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) { logerror("fcntl ctlconn"); close(fd); return; } pfd[PFD_CTLCONN].fd = fd; pfd[PFD_CTLCONN].events = POLLIN; ctl_state = CTL_READING_CMD; ctl_cmd_bytes = 0; } static struct filed *find_membuf_log(const char *name) { struct filed *f; for (f = Files; f != NULL; f = f->f_next) { if (f->f_type == F_MEMBUF && strcmp(f->f_un.f_mb.f_mname, name) == 0) break; } return (f); } void ctlconn_read_handler(void) { ssize_t n; struct filed *f; u_int32_t flags = 0; size_t reply_text_size; struct ctl_reply_hdr *reply_hdr = (struct ctl_reply_hdr *)ctl_reply; char *reply_text = ctl_reply + CTL_HDR_LEN; if (ctl_state != CTL_READING_CMD) { /* Shouldn't be here! */ logerror("ctlconn_read with bad ctl_state"); ctlconn_cleanup(); return; } retry: n = read(pfd[PFD_CTLCONN].fd, (char*)&ctl_cmd + ctl_cmd_bytes, sizeof(ctl_cmd) - ctl_cmd_bytes); switch (n) { case -1: if (errno == EINTR) goto retry; logerror("ctlconn read"); /* FALLTHROUGH */ case 0: ctlconn_cleanup(); return; default: ctl_cmd_bytes += n; } if (ctl_cmd_bytes < sizeof(ctl_cmd)) return; if (ntohl(ctl_cmd.version) != CTL_VERSION) { logerror("Unknown client protocol version"); ctlconn_cleanup(); return; } /* Ensure that logname is \0 terminated */ if (memchr(ctl_cmd.logname, '\0', sizeof(ctl_cmd.logname)) == NULL) { logerror("Corrupt ctlsock command"); ctlconn_cleanup(); return; } *reply_text = '\0'; ctl_reply_size = reply_text_size = ctl_reply_offset = 0; memset(reply_hdr, '\0', sizeof(*reply_hdr)); ctl_cmd.cmd = ntohl(ctl_cmd.cmd); dprintf("ctlcmd %x logname \"%s\"\n", ctl_cmd.cmd, ctl_cmd.logname); switch (ctl_cmd.cmd) { case CMD_READ: case CMD_READ_CLEAR: case CMD_FLAGS: f = find_membuf_log(ctl_cmd.logname); if (f == NULL) { strlcpy(reply_text, "No such log\n", MAX_MEMBUF); } else { if (ctl_cmd.cmd != CMD_FLAGS) { ringbuf_to_string(reply_text, MAX_MEMBUF, f->f_un.f_mb.f_rb); } if (f->f_un.f_mb.f_overflow) flags |= CTL_HDR_FLAG_OVERFLOW; if (ctl_cmd.cmd == CMD_READ_CLEAR) { ringbuf_clear(f->f_un.f_mb.f_rb); f->f_un.f_mb.f_overflow = 0; } } reply_text_size = strlen(reply_text); break; case CMD_CLEAR: f = find_membuf_log(ctl_cmd.logname); if (f == NULL) { strlcpy(reply_text, "No such log\n", MAX_MEMBUF); } else { ringbuf_clear(f->f_un.f_mb.f_rb); if (f->f_un.f_mb.f_overflow) flags |= CTL_HDR_FLAG_OVERFLOW; f->f_un.f_mb.f_overflow = 0; strlcpy(reply_text, "Log cleared\n", MAX_MEMBUF); } reply_text_size = strlen(reply_text); break; case CMD_LIST: for (f = Files; f != NULL; f = f->f_next) { if (f->f_type == F_MEMBUF) { strlcat(reply_text, f->f_un.f_mb.f_mname, MAX_MEMBUF); if (f->f_un.f_mb.f_overflow) { strlcat(reply_text, "*", MAX_MEMBUF); flags |= CTL_HDR_FLAG_OVERFLOW; } strlcat(reply_text, " ", MAX_MEMBUF); } } strlcat(reply_text, "\n", MAX_MEMBUF); reply_text_size = strlen(reply_text); break; default: logerror("Unsupported ctlsock command"); ctlconn_cleanup(); return; } reply_hdr->version = htonl(CTL_VERSION); reply_hdr->flags = htonl(flags); ctl_reply_size = reply_text_size + CTL_HDR_LEN; dprintf("ctlcmd reply length %lu\n", (u_long)ctl_reply_size); /* Otherwise, set up to write out reply */ ctl_state = CTL_WRITING_REPLY; pfd[PFD_CTLCONN].events = POLLOUT; pfd[PFD_CTLCONN].revents = 0; } void ctlconn_write_handler(void) { ssize_t n; if (ctl_state != CTL_WRITING_REPLY) { /* Shouldn't be here! */ logerror("ctlconn_write with bad ctl_state"); ctlconn_cleanup(); return; } retry: n = write(pfd[PFD_CTLCONN].fd, ctl_reply + ctl_reply_offset, ctl_reply_size - ctl_reply_offset); switch (n) { case -1: if (errno == EINTR) goto retry; if (errno != EPIPE) logerror("ctlconn write"); /* FALLTHROUGH */ case 0: ctlconn_cleanup(); return; default: ctl_reply_offset += n; } if (ctl_reply_offset >= ctl_reply_size) ctlconn_cleanup(); }