usr.sbin/syslogd/syslogd.c

/*
 * 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.
 * 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
#endif /* not lint */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

/*
 *  syslogd -- log system messages
 *
 * This program implements a system log. It takes a series of lines.
 * Each line may have a priority, signified as "<n>" 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)
 * 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.
 */

/* Maximum number of characters in time of last occurrence */
#define MAXDATELEN      16
#define MAXLINE         1024            /* maximum line length */
#define MAXSVLINE       MAXLINE         /* 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 */
#define RCVBUF_MINSIZE  (80 * 1024)     /* minimum size of dgram rcv buffer */

#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/queue.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/syslimits.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <sys/types.h>

#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>

#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <libutil.h>
#include <limits.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include <utmpx.h>

#include "pathnames.h"
#include "ttymsg.h"

#define SYSLOG_NAMES
#include <sys/syslog.h>

const char      *ConfFile = _PATH_LOGCONF;
const char      *PidFile = _PATH_LOGPID;
const char      ctty[] = _PATH_CONSOLE;
static const char       include_str[] = "include";
static const char       include_ext[] = ".conf";

#define dprintf         if (Debug) printf

#define MAXUNAMES       20      /* maximum number of user names */

/*
 * List of hosts for binding.
 */
static STAILQ_HEAD(, host) hqueue;
struct host {
        char                    *name;
        STAILQ_ENTRY(host)      next;
};

/*
 * Unix sockets.
 * We have two default sockets, one with 666 permissions,
 * and one for privileged programs.
 */
struct funix {
        int                     s;
        const char              *name;
        mode_t                  mode;
        STAILQ_ENTRY(funix)     next;
};
struct funix funix_secure =     { -1, _PATH_LOG_PRIV, S_IRUSR | S_IWUSR,
                                { NULL } };
struct funix funix_default =    { -1, _PATH_LOG, DEFFILEMODE,
                                { &funix_secure } };

STAILQ_HEAD(, funix) funixes =  { &funix_default,
                                &(funix_secure.next.stqe_next) };

/*
 * 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.
 * We require f_file to be valid if f_type is F_FILE, F_CONSOLE, F_TTY
 * or if f_type is F_PIPE and f_pid > 0.
 */

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][MAXLOGNAME];
                struct {
                        char    f_hname[MAXHOSTNAMELEN];
                        struct addrinfo *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[MAXDATELEN];         /* 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 */
        u_int   f_repeatcount;                  /* number of "repeated" msgs */
        int     f_flags;                        /* file-specific flags */
#define FFLAG_SYNC 0x01
#define FFLAG_NEEDSYNC  0x02
};

/*
 * 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 sockaddr_storage addr;
                        struct sockaddr_storage 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 */

const char *TypeNames[8] = {
        "UNUSED",       "FILE",         "TTY",          "CONSOLE",
        "FORW",         "USERS",        "WALL",         "PIPE"
};

static struct filed *Files;     /* Log files that we write to */
static struct filed consfile;   /* Console */

static int      Debug;          /* debug flag */
static int      Foreground = 0; /* Run in foreground, instead of daemonizing */
static int      resolve = 1;    /* resolve hostname */
static char     LocalHostName[MAXHOSTNAMELEN];  /* our hostname */
static const char *LocalDomain; /* our local domain name */
static int      *finet;         /* Internet datagram sockets */
static int      fklog = -1;     /* /dev/klog */
static int      Initialized;    /* set when we have initialized ourselves */
static int      MarkInterval = 20 * 60; /* interval between marks in seconds */
static int      MarkSeq;        /* mark sequence number */
static int      NoBind;         /* don't bind() as suggested by RFC 3164 */
static int      SecureMode;     /* when true, receive only unix domain socks */
#ifdef INET6
static int      family = PF_UNSPEC; /* protocol family (IPv4, IPv6 or both) */
#else
static int      family = PF_INET; /* protocol family (IPv4 only) */
#endif
static int      mask_C1 = 1;    /* mask characters from 0x80 - 0x9F */
static int      send_to_all;    /* send message to all IPv4/IPv6 addresses */
static int      use_bootfile;   /* log entire bootfile for every kern msg */
static int      no_compress;    /* don't compress messages (1=pipes, 2=all) */
static int      logflags = O_WRONLY|O_APPEND; /* flags used to open log files */

static char     bootfile[MAXLINE+1]; /* booted kernel file */

struct allowedpeer *AllowedPeers; /* List of allowed peers */
static int      NumAllowed;     /* Number of entries in AllowedPeers */
static int      RemoteAddDate;  /* Always set the date on remote messages */

static int      UniquePriority; /* Only log specified priority? */
static int      LogFacPri;      /* Put facility and priority in log message: */
                                /* 0=no, 1=numeric, 2=names */
static int      KeepKernFac;    /* Keep remotely logged kernel facility */
static int      needdofsync = 0; /* Are any file(s) waiting to be fsynced? */
static struct pidfh *pfh;

volatile sig_atomic_t MarkSet, WantDie;

static int      allowaddr(char *);
static void     cfline(const char *, struct filed *,
                    const char *, const char *);
static const char *cvthname(struct sockaddr *);
static void     deadq_enter(pid_t, const char *);
static int      deadq_remove(pid_t);
static int      decode(const char *, const CODE *);
static void     die(int) __dead2;
static void     dodie(int);
static void     dofsync(void);
static void     domark(int);
static void     fprintlog(struct filed *, int, const char *);
static int      *socksetup(int, char *);
static void     init(int);
static void     logerror(const char *);
static void     logmsg(int, const char *, const char *, int);
static void     log_deadchild(pid_t, int, const char *);
static void     markit(void);
static int      skip_message(const char *, const char *, int);
static void     printline(const char *, char *, int);
static void     printsys(char *);
static int      p_open(const char *, pid_t *);
static void     readklog(void);
static void     reapchild(int);
static const char *ttymsg_check(struct iovec *, int, char *, int);
static void     usage(void);
static int      validate(struct sockaddr *, const char *);
static void     unmapped(struct sockaddr *);
static void     wallmsg(struct filed *, struct iovec *, const int iovlen);
static int      waitdaemon(int, int, int);
static void     timedout(int);
static void     increase_rcvbuf(int);

static void
close_filed(struct filed *f)
{

        if (f == NULL || f->f_file == -1)
                return;

        switch (f->f_type) {
        case F_FORW:
            if (f->f_un.f_forw.f_addr) {
                freeaddrinfo(f->f_un.f_forw.f_addr);
                f->f_un.f_forw.f_addr = NULL;
            }
            /*FALLTHROUGH*/

        case F_FILE:
        case F_TTY:
        case F_CONSOLE:
                f->f_type = F_UNUSED;
                break;
        case F_PIPE:
                f->f_un.f_pipe.f_pid = 0;
                break;
        }
        (void)close(f->f_file);
        f->f_file = -1;
}

int
main(int argc, char *argv[])
{
        int ch, i, fdsrmax = 0, l;
        struct sockaddr_un sunx, fromunix;
        struct sockaddr_storage frominet;
        fd_set *fdsr = NULL;
        char line[MAXLINE + 1];
        const char *hname;
        struct timeval tv, *tvp;
        struct sigaction sact;
        struct host *host;
        struct funix *fx, *fx1;
        sigset_t mask;
        pid_t ppid = 1, spid;
        socklen_t len;

        if (madvise(NULL, 0, MADV_PROTECT) != 0)
                dprintf("madvise() failed: %s\n", strerror(errno));

        STAILQ_INIT(&hqueue);

        while ((ch = getopt(argc, argv, "468Aa:b:cCdf:Fkl:m:nNop:P:sS:Tuv"))
            != -1)
                switch (ch) {
                case '4':
                        family = PF_INET;
                        break;
#ifdef INET6
                case '6':
                        family = PF_INET6;
                        break;
#endif
                case '8':
                        mask_C1 = 0;
                        break;
                case 'A':
                        send_to_all++;
                        break;
                case 'a':               /* allow specific network addresses only */
                        if (allowaddr(optarg) == -1)
                                usage();
                        break;
                case 'b':
                   {
                        if ((host = malloc(sizeof(struct host))) == NULL)
                                err(1, "malloc failed");
                        host->name = optarg;
                        STAILQ_INSERT_TAIL(&hqueue, host, next);
                        break;
                   }
                case 'c':
                        no_compress++;
                        break;
                case 'C':
                        logflags |= O_CREAT;
                        break;
                case 'd':               /* debug */
                        Debug++;
                        break;
                case 'f':               /* configuration file */
                        ConfFile = optarg;
                        break;
                case 'F':               /* run in foreground instead of daemon */
                        Foreground++;
                        break;
                case 'k':               /* keep remote kern fac */
                        KeepKernFac = 1;
                        break;
                case 'l':
                    {
                        long    perml;
                        mode_t  mode;
                        char    *name, *ep;

                        if (optarg[0] == '/') {
                                mode = DEFFILEMODE;
                                name = optarg;
                        } else if ((name = strchr(optarg, ':')) != NULL) {
                                *name++ = '\0';
                                if (name[0] != '/')
                                        errx(1, "socket name must be absolute "
                                            "path");
                                if (isdigit(*optarg)) {
                                        perml = strtol(optarg, &ep, 8);
                                    if (*ep || perml < 0 ||
                                        perml & ~(S_IRWXU|S_IRWXG|S_IRWXO))
                                            errx(1, "invalid mode %s, exiting",
                                                optarg);
                                    mode = (mode_t )perml;
                                } else
                                        errx(1, "invalid mode %s, exiting",
                                            optarg);
                        } else  /* doesn't begin with '/', and no ':' */
                                errx(1, "can't parse path %s", optarg);

                        if (strlen(name) >= sizeof(sunx.sun_path))
                                errx(1, "%s path too long, exiting", name);
                        if ((fx = malloc(sizeof(struct funix))) == NULL)
                                err(1, "malloc failed");
                        fx->s = -1;
                        fx->name = name;
                        fx->mode = mode;
                        STAILQ_INSERT_TAIL(&funixes, fx, next);
                        break;
                   }
                case 'm':               /* mark interval */
                        MarkInterval = atoi(optarg) * 60;
                        break;
                case 'N':
                        NoBind = 1;
                        SecureMode = 1;
                        break;
                case 'n':
                        resolve = 0;
                        break;
                case 'o':
                        use_bootfile = 1;
                        break;
                case 'p':               /* path */
                        if (strlen(optarg) >= sizeof(sunx.sun_path))
                                errx(1, "%s path too long, exiting", optarg);
                        funix_default.name = optarg;
                        break;
                case 'P':               /* path for alt. PID */
                        PidFile = optarg;
                        break;
                case 's':               /* no network mode */
                        SecureMode++;
                        break;
                case 'S':               /* path for privileged originator */
                        if (strlen(optarg) >= sizeof(sunx.sun_path))
                                errx(1, "%s path too long, exiting", optarg);
                        funix_secure.name = optarg;
                        break;
                case 'T':
                        RemoteAddDate = 1;
                        break;
                case 'u':               /* only log specified priority */
                        UniquePriority++;
                        break;
                case 'v':               /* log facility and priority */
                        LogFacPri++;
                        break;
                default:
                        usage();
                }
        if ((argc -= optind) != 0)
                usage();

        pfh = pidfile_open(PidFile, 0600, &spid);
        if (pfh == NULL) {
                if (errno == EEXIST)
                        errx(1, "syslogd already running, pid: %d", spid);
                warn("cannot open pid file");
        }

        if ((!Foreground) && (!Debug)) {
                ppid = waitdaemon(0, 0, 30);
                if (ppid < 0) {
                        warn("could not become daemon");
                        pidfile_remove(pfh);
                        exit(1);
                }
        } else if (Debug) {
                setlinebuf(stdout);
        }

        if (NumAllowed)
                endservent();

        consfile.f_type = F_CONSOLE;
        (void)strlcpy(consfile.f_un.f_fname, ctty + sizeof _PATH_DEV - 1,
            sizeof(consfile.f_un.f_fname));
        (void)strlcpy(bootfile, getbootfile(), sizeof(bootfile));
        (void)signal(SIGTERM, dodie);
        (void)signal(SIGINT, Debug ? dodie : SIG_IGN);
        (void)signal(SIGQUIT, Debug ? dodie : 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
        STAILQ_FOREACH_SAFE(fx, &funixes, next, fx1) {
                (void)unlink(fx->name);
                memset(&sunx, 0, sizeof(sunx));
                sunx.sun_family = AF_LOCAL;
                (void)strlcpy(sunx.sun_path, fx->name, sizeof(sunx.sun_path));
                fx->s = socket(PF_LOCAL, SOCK_DGRAM, 0);
                if (fx->s < 0 ||
                    bind(fx->s, (struct sockaddr *)&sunx, SUN_LEN(&sunx)) < 0 ||
                    chmod(fx->name, fx->mode) < 0) {
                        (void)snprintf(line, sizeof line,
                                        "cannot create %s", fx->name);
                        logerror(line);
                        dprintf("cannot create %s (%d)\n", fx->name, errno);
                        if (fx == &funix_default || fx == &funix_secure)
                                die(0);
                        else {
                                STAILQ_REMOVE(&funixes, fx, funix, next);
                                continue;
                        }
                }
                increase_rcvbuf(fx->s);
        }
        if (SecureMode <= 1) {
                if (STAILQ_EMPTY(&hqueue))
                        finet = socksetup(family, NULL);
                STAILQ_FOREACH(host, &hqueue, next) {
                        int *finet0, total;
                        finet0 = socksetup(family, host->name);
                        if (finet0 && !finet) {
                                finet = finet0;
                        } else if (finet0 && finet) {
                                total = *finet0 + *finet + 1;
                                finet = realloc(finet, total * sizeof(int));
                                if (finet == NULL)
                                        err(1, "realloc failed");
                                for (i = 1; i <= *finet0; i++) {
                                        finet[(*finet)+i] = finet0[i];
                                }
                                *finet = total - 1;
                                free(finet0);
                        }
                }
        }

        if (finet) {
                if (SecureMode) {
                        for (i = 0; i < *finet; i++) {
                                if (shutdown(finet[i+1], SHUT_RD) < 0 &&
                                    errno != ENOTCONN) {
                                        logerror("shutdown");
                                        if (!Debug)
                                                die(0);
                                }
                        }
                } else {
                        dprintf("listening on inet and/or inet6 socket\n");
                }
                dprintf("sending on inet and/or inet6 socket\n");
        }

        if ((fklog = open(_PATH_KLOG, O_RDONLY|O_NONBLOCK, 0)) < 0)
                dprintf("can't open %s (%d)\n", _PATH_KLOG, errno);

        /* tuck my process id away */
        pidfile_write(pfh);

        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;

        if (fklog != -1 && fklog > fdsrmax)
                fdsrmax = fklog;
        if (finet && !SecureMode) {
                for (i = 0; i < *finet; i++) {
                    if (finet[i+1] != -1 && finet[i+1] > fdsrmax)
                        fdsrmax = finet[i+1];
                }
        }
        STAILQ_FOREACH(fx, &funixes, next)
                if (fx->s > fdsrmax)
                        fdsrmax = fx->s;

        fdsr = (fd_set *)calloc(howmany(fdsrmax+1, NFDBITS),
            sizeof(fd_mask));
        if (fdsr == NULL)
                errx(1, "calloc fd_set");

        for (;;) {
                if (MarkSet)
                        markit();
                if (WantDie)
                        die(WantDie);

                bzero(fdsr, howmany(fdsrmax+1, NFDBITS) *
                    sizeof(fd_mask));

                if (fklog != -1)
                        FD_SET(fklog, fdsr);
                if (finet && !SecureMode) {
                        for (i = 0; i < *finet; i++) {
                                if (finet[i+1] != -1)
                                        FD_SET(finet[i+1], fdsr);
                        }
                }
                STAILQ_FOREACH(fx, &funixes, next)
                        FD_SET(fx->s, fdsr);

                i = select(fdsrmax+1, fdsr, NULL, NULL,
                    needdofsync ? &tv : tvp);
                switch (i) {
                case 0:
                        dofsync();
                        needdofsync = 0;
                        if (tvp) {
                                tvp = NULL;
                                if (ppid != 1)
                                        kill(ppid, SIGALRM);
                        }
                        continue;
                case -1:
                        if (errno != EINTR)
                                logerror("select");
                        continue;
                }
                if (fklog != -1 && FD_ISSET(fklog, fdsr))
                        readklog();
                if (finet && !SecureMode) {
                        for (i = 0; i < *finet; i++) {
                                if (FD_ISSET(finet[i+1], fdsr)) {
                                        len = sizeof(frominet);
                                        l = recvfrom(finet[i+1], line, MAXLINE,
                                             0, (struct sockaddr *)&frominet,
                                             &len);
                                        if (l > 0) {
                                                line[l] = '\0';
                                                hname = cvthname((struct sockaddr *)&frominet);
                                                unmapped((struct sockaddr *)&frominet);
                                                if (validate((struct sockaddr *)&frominet, hname))
                                                        printline(hname, line, RemoteAddDate ? ADDDATE : 0);
                                        } else if (l < 0 && errno != EINTR)
                                                logerror("recvfrom inet");
                                }
                        }
                }
                STAILQ_FOREACH(fx, &funixes, next) {
                        if (FD_ISSET(fx->s, fdsr)) {
                                len = sizeof(fromunix);
                                l = recvfrom(fx->s, line, MAXLINE, 0,
                                    (struct sockaddr *)&fromunix, &len);
                                if (l > 0) {
                                        line[l] = '\0';
                                        printline(LocalHostName, line, 0);
                                } else if (l < 0 && errno != EINTR)
                                        logerror("recvfrom unix");
                        }
                }
        }
        if (fdsr)
                free(fdsr);
}

static void
unmapped(struct sockaddr *sa)
{
        struct sockaddr_in6 *sin6;
        struct sockaddr_in sin4;

        if (sa->sa_family != AF_INET6)
                return;
        if (sa->sa_len != sizeof(struct sockaddr_in6) ||
            sizeof(sin4) > sa->sa_len)
                return;
        sin6 = (struct sockaddr_in6 *)sa;
        if (!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
                return;

        memset(&sin4, 0, sizeof(sin4));
        sin4.sin_family = AF_INET;
        sin4.sin_len = sizeof(struct sockaddr_in);
        memcpy(&sin4.sin_addr, &sin6->sin6_addr.s6_addr[12],
               sizeof(sin4.sin_addr));
        sin4.sin_port = sin6->sin6_port;

        memcpy(sa, &sin4, sin4.sin_len);
}

static void
usage(void)
{

        fprintf(stderr, "%s\n%s\n%s\n%s\n",
                "usage: syslogd [-468ACcdFknosTuv] [-a allowed_peer]",
                "               [-b bind_address] [-f config_file]",
                "               [-l [mode:]path] [-m mark_interval]",
                "               [-P pid_file] [-p log_socket]");
        exit(1);
}

/*
 * Take a raw input line, decode the message, and print the message
 * on the appropriate log files.
 */
static void
printline(const char *hname, char *msg, int flags)
{
        char *p, *q;
        long n;
        int c, pri;
        char line[MAXLINE + 1];

        /* test for special codes */
        p = msg;
        pri = DEFUPRI;
        if (*p == '<') {
                errno = 0;
                n = strtol(p + 1, &q, 10);
                if (*q == '>' && n >= 0 && n < INT_MAX && errno == 0) {
                        p = q + 1;
                        pri = n;
                }
        }
        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 ((pri & LOG_FACMASK) == 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 (mask_C1 && (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, flags);
}

/*
 * Read /dev/klog while data are available, split into lines.
 */
static void
readklog(void)
{
        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;
                }

                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().
 */
static void
printsys(char *msg)
{
        char *p, *q;
        long n;
        int flags, isprintf, pri;

        flags = ISKERNEL | SYNC_FILE | ADDDATE; /* fsync after write */
        p = msg;
        pri = DEFSPRI;
        isprintf = 1;
        if (*p == '<') {
                errno = 0;
                n = strtol(p + 1, &q, 10);
                if (*q == '>' && n >= 0 && n < INT_MAX && errno == 0) {
                        p = q + 1;
                        pri = n;
                        isprintf = 0;
                }
        }
        /*
         * Kernel printf's and LOG_CONSOLE messages have been displayed
         * on the console already.
         */
        if (isprintf || (pri & LOG_FACMASK) == LOG_CONSOLE)
                flags |= IGN_CONS;
        if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
                pri = DEFSPRI;
        logmsg(pri, p, LocalHostName, flags);
}

static time_t   now;

/*
 * Match a program or host name against a specification.
 * Return a non-0 value if the message must be ignored
 * based on the specification.
 */
static int
skip_message(const char *name, const char *spec, int checkcase)
{
        const char *s;
        char prev, next;
        int exclude = 0;
        /* Behaviour on explicit match */

        if (spec == NULL)
                return 0;
        switch (*spec) {
        case '-':
                exclude = 1;
                /*FALLTHROUGH*/
        case '+':
                spec++;
                break;
        default:
                break;
        }
        if (checkcase)
                s = strstr (spec, name);
        else
                s = strcasestr (spec, name);

        if (s != NULL) {
                prev = (s == spec ? ',' : *(s - 1));
                next = *(s + strlen (name));

                if (prev == ',' && (next == '\0' || next == ','))
                        /* Explicit match: skip iff the spec is an
                           exclusive one. */
                        return exclude;
        }

        /* No explicit match for this name: skip the message iff
           the spec is an inclusive one. */
        return !exclude;
}

/*
 * Log a message to the appropriate log files, users, etc. based on
 * the priority.
 */
static void
logmsg(int pri, const char *msg, const char *from, int flags)
{
        struct filed *f;
        int i, fac, msglen, omask, prilev;
        const 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 < MAXDATELEN || 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 += MAXDATELEN;
                msglen -= MAXDATELEN;
        }

        /* skip leading blanks */
        while (isspace(*msg)) {
                msg++;
                msglen--;
        }

        /* extract facility and priority level */
        if (flags & MARK)
                fac = LOG_NFACILITIES;
        else
                fac = LOG_FAC(pri);

        /* Check maximum facility number. */
        if (fac > LOG_NFACILITIES) {
                (void)sigsetmask(omask);
                return;
        }

        prilev = LOG_PRI(pri);

        /* extract program name */
        for (i = 0; i < NAME_MAX; i++) {
                if (!isprint(msg[i]) || msg[i] == ':' || msg[i] == '[' ||
                    msg[i] == '/' || isspace(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",
                    use_bootfile ? bootfile : "kernel", msg);
                msg = buf;
                msglen = strlen(buf);
        }

        /* log the message to the particular outputs */
        if (!Initialized) {
                f = &consfile;
                /*
                 * Open in non-blocking mode to avoid hangs during open
                 * and close(waiting for the port to drain).
                 */
                f->f_file = open(ctty, O_WRONLY | O_NONBLOCK, 0);

                if (f->f_file >= 0) {
                        (void)strlcpy(f->f_lasttime, timestamp,
                                sizeof(f->f_lasttime));
                        fprintlog(f, flags, msg);
                        close(f->f_file);
                        f->f_file = -1;
                }
                (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 (skip_message(from, f->f_host, 0))
                        continue;

                /* skip messages with the incorrect program name */
                if (skip_message(prog, f->f_program, 1))
                        continue;

                /* skip message to console if it has already been printed */
                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 (no_compress - (f->f_type != F_PIPE) < 1 &&
                    (flags & MARK) == 0 && msglen == f->f_prevlen &&
                    !strcmp(msg, f->f_prevline) &&
                    !strcasecmp(from, f->f_prevhost)) {
                        (void)strlcpy(f->f_lasttime, timestamp,
                                sizeof(f->f_lasttime));
                        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)strlcpy(f->f_lasttime, timestamp,
                                sizeof(f->f_lasttime));
                        (void)strlcpy(f->f_prevhost, from,
                            sizeof(f->f_prevhost));
                        if (msglen < MAXSVLINE) {
                                f->f_prevlen = msglen;
                                (void)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);
                        }
                }
        }
        (void)sigsetmask(omask);
}

static void
dofsync(void)
{
        struct filed *f;

        for (f = Files; f; f = f->f_next) {
                if ((f->f_type == F_FILE) &&
                    (f->f_flags & FFLAG_NEEDSYNC)) {
                        f->f_flags &= ~FFLAG_NEEDSYNC;
                        (void)fsync(f->f_file);
                }
        }
}

#define IOV_SIZE 7
static void
fprintlog(struct filed *f, int flags, const char *msg)
{
        struct iovec iov[IOV_SIZE];
        struct iovec *v;
        struct addrinfo *r;
        int i, l, lsent = 0;
        char line[MAXLINE + 1], repbuf[80], greetings[200], *wmsg = NULL;
        char nul[] = "", space[] = " ", lf[] = "\n", crlf[] = "\r\n";
        const char *msgret;

        v = iov;
        if (f->f_type == F_WALL) {
                v->iov_base = greetings;
                /* The time displayed is not synchornized with the other log
                 * destinations (like messages).  Following fragment was using
                 * ctime(&now), which was updating the time every 30 sec.
                 * With f_lasttime, time is synchronized correctly.
                 */
                v->iov_len = snprintf(greetings, sizeof greetings,
                    "\r\n\7Message from syslogd@%s at %.24s ...\r\n",
                    f->f_prevhost, f->f_lasttime);
                if (v->iov_len >= sizeof greetings)
                        v->iov_len = sizeof greetings - 1;
                v++;
                v->iov_base = nul;
                v->iov_len = 0;
                v++;
        } else {
                v->iov_base = f->f_lasttime;
                v->iov_len = strlen(f->f_lasttime);
                v++;
                v->iov_base = space;
                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);
                const char *f_s = NULL;
                char f_n[5];    /* Hollow laugh */
                const char *p_s = NULL;
                char p_n[5];    /* Hollow laugh */

                if (LogFacPri > 1) {
                  const 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 = nul;
                v->iov_len = 0;
        }
        v++;

        v->iov_base = f->f_prevhost;
        v->iov_len = strlen(v->iov_base);
        v++;
        v->iov_base = space;
        v->iov_len = 1;
        v++;

        if (msg) {
                wmsg = strdup(msg); /* XXX iov_base needs a `const' sibling. */
                if (wmsg == NULL) {
                        logerror("strdup");
                        exit(1);
                }
                v->iov_base = wmsg;
                v->iov_len = strlen(msg);
        } else if (f->f_prevcount > 1) {
                v->iov_base = repbuf;
                v->iov_len = snprintf(repbuf, sizeof 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) {
                int port;
        case F_UNUSED:
                dprintf("\n");
                break;

        case F_FORW:
                port = (int)ntohs(((struct sockaddr_in *)
                            (f->f_un.f_forw.f_addr->ai_addr))->sin_port);
                if (port != 514) {
                        dprintf(" %s:%d\n", f->f_un.f_forw.f_hname, port);
                } else {
                        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, (char *)iov[0].iov_base,
                            f->f_prevhost, (char *)iov[5].iov_base);
                else
                        l = snprintf(line, sizeof line - 1, "<%d>%.15s %s",
                             f->f_prevpri, (char *)iov[0].iov_base,
                            (char *)iov[5].iov_base);
                if (l < 0)
                        l = 0;
                else if (l > MAXLINE)
                        l = MAXLINE;

                if (finet) {
                        for (r = f->f_un.f_forw.f_addr; r; r = r->ai_next) {
                                for (i = 0; i < *finet; i++) {
#if 0
                                        /*
                                         * should we check AF first, or just
                                         * trial and error? FWD
                                         */
                                        if (r->ai_family ==
                                            address_family_of(finet[i+1]))
#endif
                                        lsent = sendto(finet[i+1], line, l, 0,
                                            r->ai_addr, r->ai_addrlen);
                                        if (lsent == l)
                                                break;
                                }
                                if (lsent == l && !send_to_all)
                                        break;
                        }
                        dprintf("lsent/l: %d/%d\n", lsent, l);
                        if (lsent != l) {
                                int e = errno;
                                logerror("sendto");
                                errno = e;
                                switch (errno) {
                                case ENOBUFS:
                                case ENETDOWN:
                                case ENETUNREACH:
                                case EHOSTUNREACH:
                                case EHOSTDOWN:
                                case EADDRNOTAVAIL:
                                        break;
                                /* case EBADF: */
                                /* case EACCES: */
                                /* case ENOTSOCK: */
                                /* case EFAULT: */
                                /* case EMSGSIZE: */
                                /* case EAGAIN: */
                                /* case ENOBUFS: */
                                /* case ECONNREFUSED: */
                                default:
                                        dprintf("removing entry: errno=%d\n", e);
                                        f->f_type = F_UNUSED;
                                        break;
                                }
                        }
                }
                break;

        case F_FILE:
                dprintf(" %s\n", f->f_un.f_fname);
                v->iov_base = lf;
                v->iov_len = 1;
                if (writev(f->f_file, iov, IOV_SIZE) < 0) {
                        /*
                         * If writev(2) fails for potentially transient errors
                         * like the filesystem being full, ignore it.
                         * Otherwise remove this logfile from the list.
                         */
                        if (errno != ENOSPC) {
                                int e = errno;
                                close_filed(f);
                                errno = e;
                                logerror(f->f_un.f_fname);
                        }
                } else if ((flags & SYNC_FILE) && (f->f_flags & FFLAG_SYNC)) {
                        f->f_flags |= FFLAG_NEEDSYNC;
                        needdofsync = 1;
                }
                break;

        case F_PIPE:
                dprintf(" %s\n", f->f_un.f_pipe.f_pname);
                v->iov_base = lf;
                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) {
                                logerror(f->f_un.f_pipe.f_pname);
                                break;
                        }
                }
                if (writev(f->f_file, iov, IOV_SIZE) < 0) {
                        int e = errno;

                        close_filed(f);
                        deadq_enter(f->f_un.f_pipe.f_pid,
                                    f->f_un.f_pipe.f_pname);
                        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 = crlf;
                v->iov_len = 2;

                errno = 0;      /* ttymsg() only sometimes returns an errno */
                if ((msgret = ttymsg(iov, IOV_SIZE, 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 = crlf;
                v->iov_len = 2;
                wallmsg(f, iov, IOV_SIZE);
                break;
        }
        f->f_prevcount = 0;
        free(wmsg);
}

/*
 *  WALLMSG -- Write a message to the world at large
 *
 *      Write the specified message to either the entire
 *      world, or a list of approved users.
 */
static void
wallmsg(struct filed *f, struct iovec *iov, const int iovlen)
{
        static int reenter;                     /* avoid calling ourselves */
        struct utmpx *ut;
        int i;
        const char *p;

        if (reenter++)
                return;
        setutxent();
        /* NOSTRICT */
        while ((ut = getutxent()) != NULL) {
                if (ut->ut_type != USER_PROCESS)
                        continue;
                if (f->f_type == F_WALL) {
                        if ((p = ttymsg(iov, iovlen, ut->ut_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 (!strcmp(f->f_un.f_uname[i], ut->ut_user)) {
                                if ((p = ttymsg_check(iov, iovlen, ut->ut_line,
                                    TTYMSGTIME)) != NULL) {
                                        errno = 0;      /* already in msg */
                                        logerror(p);
                                }
                                break;
                        }
                }
        }
        endutxent();
        reenter = 0;
}

/*
 * Wrapper routine for ttymsg() that checks the terminal for messages enabled.
 */
static const char *
ttymsg_check(struct iovec *iov, int iovcnt, char *line, int tmout)
{
        static char device[1024];
        static char errbuf[1024];
        struct stat sb;

        (void) snprintf(device, sizeof(device), "%s%s", _PATH_DEV, line);

        if (stat(device, &sb) < 0) {
                (void) snprintf(errbuf, sizeof(errbuf),
                    "%s: %s", device, strerror(errno));
                return (errbuf);
        }
        if ((sb.st_mode & S_IWGRP) == 0)
                /* Messages disabled. */
                return (NULL);
        return ttymsg(iov, iovcnt, line, tmout);
}

static void
reapchild(int signo __unused)
{
        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) {
                                close_filed(f);
                                log_deadchild(pid, status,
                                              f->f_un.f_pipe.f_pname);
                                break;
                        }
          oncemore:
                continue;
        }
}

/*
 * Return a printable representation of a host address.
 */
static const char *
cvthname(struct sockaddr *f)
{
        int error, hl;
        sigset_t omask, nmask;
        static char hname[NI_MAXHOST], ip[NI_MAXHOST];

        error = getnameinfo((struct sockaddr *)f,
                            ((struct sockaddr *)f)->sa_len,
                            ip, sizeof ip, NULL, 0, NI_NUMERICHOST);
        dprintf("cvthname(%s)\n", ip);

        if (error) {
                dprintf("Malformed from address %s\n", gai_strerror(error));
                return ("???");
        }
        if (!resolve)
                return (ip);

        sigemptyset(&nmask);
        sigaddset(&nmask, SIGHUP);
        sigprocmask(SIG_BLOCK, &nmask, &omask);
        error = getnameinfo((struct sockaddr *)f,
                            ((struct sockaddr *)f)->sa_len,
                            hname, sizeof hname, NULL, 0, NI_NAMEREQD);
        sigprocmask(SIG_SETMASK, &omask, NULL);
        if (error) {
                dprintf("Host name for your address (%s) unknown\n", ip);
                return (ip);
        }
        hl = strlen(hname);
        if (hl > 0 && hname[hl-1] == '.')
                hname[--hl] = '\0';
        trimdomain(hname, hl);
        return (hname);
}

static void
dodie(int signo)
{

        WantDie = signo;
}

static void
domark(int signo __unused)
{

        MarkSet = 1;
}

/*
 * Print syslogd errors some place.
 */
static void
logerror(const char *type)
{
        char buf[512];
        static int recursed = 0;

        /* If there's an error while trying to log an error, give up. */
        if (recursed)
                return;
        recursed++;
        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);
        recursed--;
}

static void
die(int signo)
{
        struct filed *f;
        struct funix *fx;
        int was_initialized;
        char buf[100];

        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 && f->f_un.f_pipe.f_pid > 0)
                        close_filed(f);
        }
        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);
        }
        STAILQ_FOREACH(fx, &funixes, next)
                (void)unlink(fx->name);
        pidfile_remove(pfh);

        exit(1);
}

static int
configfiles(const struct dirent *dp)
{
        const char *p;
        size_t ext_len;

        if (dp->d_name[0] == '.')
                return (0);

        ext_len = sizeof(include_ext) -1;

        if (dp->d_namlen <= ext_len)
                return (0);

        p = &dp->d_name[dp->d_namlen - ext_len];
        if (strcmp(p, include_ext) != 0)
                return (0);

        return (1);
}

static struct filed **
readconfigfile(FILE *cf, struct filed **nextp, int allow_includes)
{
        FILE *cf2;
        struct filed *f;
        struct dirent **ent;
        char cline[LINE_MAX];
        char host[MAXHOSTNAMELEN];
        char prog[LINE_MAX];
        char file[MAXPATHLEN];
        char *p, *tmp;
        int i, nents;
        size_t include_len;

        /*
         *  Foreach line in the conf table, open that file.
         */
        f = NULL;
        include_len = sizeof(include_str) -1;
        (void)strlcpy(host, "*", sizeof(host));
        (void)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:
                 * following lines apply only to that program.
                 */
                for (p = cline; isspace(*p); ++p)
                        continue;
                if (*p == 0)
                        continue;
                if (allow_includes &&
                    strncmp(p, include_str, include_len) == 0 &&
                    isspace(p[include_len])) {
                        p += include_len;
                        while (isspace(*p))
                                p++;
                        tmp = p;
                        while (*tmp != '\0' && !isspace(*tmp))
                                tmp++;
                        *tmp = '\0';
                        dprintf("Trying to include files in '%s'\n", p);
                        nents = scandir(p, &ent, configfiles, alphasort);
                        if (nents == -1) {
                                dprintf("Unable to open '%s': %s\n", p,
                                    strerror(errno));
                                continue;
                        }
                        for (i = 0; i < nents; i++) {
                                if (snprintf(file, sizeof(file), "%s/%s", p,
                                    ent[i]->d_name) >= (int)sizeof(file)) {
                                        dprintf("ignoring path too long: "
                                            "'%s/%s'\n", p, ent[i]->d_name);
                                        free(ent[i]);
                                        continue;
                                }
                                free(ent[i]);
                                cf2 = fopen(file, "r");
                                if (cf2 == NULL)
                                        continue;
                                dprintf("reading %s\n", file);
                                nextp = readconfigfile(cf2, nextp, 0);
                                fclose(cf2);
                        }
                        free(ent);
                        continue;
                }
                if (*p == '#') {
                        p++;
                        if (*p != '!' && *p != '+' && *p != '-')
                                continue;
                }
                if (*p == '+' || *p == '-') {
                        host[0] = *p++;
                        while (isspace(*p))
                                p++;
                        if ((!*p) || (*p == '*')) {
                                (void)strlcpy(host, "*", sizeof(host));
                                continue;
                        }
                        if (*p == '@')
                                p = LocalHostName;
                        for (i = 1; i < MAXHOSTNAMELEN - 1; i++) {
                                if (!isalnum(*p) && *p != '.' && *p != '-'
                                    && *p != ',' && *p != ':' && *p != '%')
                                        break;
                                host[i] = *p++;
                        }
                        host[i] = '\0';
                        continue;
                }
                if (*p == '!') {
                        p++;
                        while (isspace(*p)) p++;
                        if ((!*p) || (*p == '*')) {
                                (void)strlcpy(prog, "*", sizeof(prog));
                                continue;
                        }
                        for (i = 0; i < LINE_MAX - 1; i++) {
                                if (!isprint(p[i]) || isspace(p[i]))
                                        break;
                                prog[i] = p[i];
                        }
                        prog[i] = 0;
                        continue;
                }
                for (p = cline + 1; *p != '\0'; p++) {
                        if (*p != '#')
                                continue;
                        if (*(p - 1) == '\\') {
                                strcpy(p - 1, p);
                                p--;
                                continue;
                        }
                        *p = '\0';
                        break;
                }
                for (i = strlen(cline) - 1; i >= 0 && isspace(cline[i]); i--)
                        cline[i] = '\0';
                f = (struct filed *)calloc(1, sizeof(*f));
                if (f == NULL) {
                        logerror("calloc");
                        exit(1);
                }
                *nextp = f;
                nextp = &f->f_next;
                cfline(cline, f, prog, host);
        }
        return nextp;
}

/*
 *  INIT -- Initialize syslogd from configuration table
 */
static void
init(int signo)
{
        int i;
        FILE *cf;
        struct filed *f, *next, **nextp;
        char *p;
        char oldLocalHostName[MAXHOSTNAMELEN];
        char hostMsg[2*MAXHOSTNAMELEN+40];
        char bootfileMsg[LINE_MAX];

        dprintf("init\n");

        /*
         * Load hostname (may have changed).
         */
        if (signo != 0)
                (void)strlcpy(oldLocalHostName, LocalHostName,
                    sizeof(oldLocalHostName));
        if (gethostname(LocalHostName, sizeof(LocalHostName)))
                err(EX_OSERR, "gethostname() failed");
        if ((p = strchr(LocalHostName, '.')) != NULL) {
                *p++ = '\0';
                LocalDomain = p;
        } else {
                LocalDomain = "";
        }

        /*
         * Load / reload timezone data (in case it changed).
         *
         * Just calling tzset() again does not work, the timezone code
         * caches the result.  However, by setting the TZ variable, one
         * can defeat the caching and have the timezone code really
         * reload the timezone data.  Respect any initial setting of
         * TZ, in case the system is configured specially.
         */
        dprintf("loading timezone data via tzset()\n");
        if (getenv("TZ")) {
                tzset();
        } else {
                setenv("TZ", ":/etc/localtime", 1);
                tzset();
                unsetenv("TZ");
        }

        /*
         *  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:
                        close_filed(f);
                        break;
                case F_PIPE:
                        close_filed(f);
                        deadq_enter(f->f_un.f_pipe.f_pid,
                                    f->f_un.f_pipe.f_pname);
                        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));
                if (*nextp == NULL) {
                        logerror("calloc");
                        exit(1);
                }
                cfline("*.ERR\t/dev/console", *nextp, "*", "*");
                (*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f));
                if ((*nextp)->f_next == NULL) {
                        logerror("calloc");
                        exit(1);
                }
                cfline("*.PANIC\t*", (*nextp)->f_next, "*", "*");
                Initialized = 1;
                return;
        }

        readconfigfile(cf, &Files, 1);

        /* close the configuration file */
        (void)fclose(cf);

        Initialized = 1;

        if (Debug) {
                int port;
                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:
                                port = (int)ntohs(((struct sockaddr_in *)
                                    (f->f_un.f_forw.f_addr->ai_addr))->sin_port);
                                if (port != 514) {
                                        printf("%s:%d",
                                                f->f_un.f_forw.f_hname, port);
                                } else {
                                        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");
        /*
         * Log a change in hostname, but only on a restart.
         */
        if (signo != 0 && strcmp(oldLocalHostName, LocalHostName) != 0) {
                (void)snprintf(hostMsg, sizeof(hostMsg),
                    "syslogd: hostname changed, \"%s\" to \"%s\"",
                    oldLocalHostName, LocalHostName);
                logmsg(LOG_SYSLOG|LOG_INFO, hostMsg, LocalHostName, ADDDATE);
                dprintf("%s\n", hostMsg);
        }
        /*
         * Log the kernel boot file if we aren't going to use it as
         * the prefix, and if this is *not* a restart.
         */
        if (signo == 0 && !use_bootfile) {
                (void)snprintf(bootfileMsg, sizeof(bootfileMsg),
                    "syslogd: kernel boot file is %s", bootfile);
                logmsg(LOG_KERN|LOG_INFO, bootfileMsg, LocalHostName, ADDDATE);
                dprintf("%s\n", bootfileMsg);
        }
}

/*
 * Crack a configuration file line
 */
static void
cfline(const char *line, struct filed *f, const char *prog, const char *host)
{
        struct addrinfo hints, *res;
        int error, i, pri, syncfile;
        const char *p, *q;
        char *bp;
        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) {
                int hl;

                f->f_host = strdup(host);
                if (f->f_host == NULL) {
                        logerror("strdup");
                        exit(1);
                }
                hl = strlen(f->f_host);
                if (hl > 0 && f->f_host[hl-1] == '.')
                        f->f_host[--hl] = '\0';
                trimdomain(f->f_host, hl);
        }

        /* save program name if any */
        if (prog && *prog == '*')
                prog = NULL;
        if (prog) {
                f->f_program = strdup(prog);
                if (f->f_program == NULL) {
                        logerror("strdup");
                        exit(1);
                }
        }

        /* scan through the list of selectors */
        for (p = line; *p && *p != '\t' && *p != ' ';) {
                int pri_done;
                int pri_cmp;
                int pri_invert;

                /* 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;
                pri_invert = 0;
                if (*q == '!') {
                        pri_invert = 1;
                        q++;
                }
                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;
                        }
                }

                /* 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;
                        pri_cmp = PRI_LT | PRI_EQ | PRI_GT;
                } else {
                        /* Ignore trailing spaces. */
                        for (i = strlen(buf) - 1; i >= 0 && buf[i] == ' '; i--)
                                buf[i] = '\0';

                        pri = decode(buf, prioritynames);
                        if (pri < 0) {
                                errno = 0;
                                (void)snprintf(ebuf, sizeof ebuf,
                                    "unknown priority name \"%s\"", buf);
                                logerror(ebuf);
                                return;
                        }
                }
                if (!pri_cmp)
                        pri_cmp = (UniquePriority)
                                  ? (PRI_EQ)
                                  : (PRI_EQ | PRI_GT)
                                  ;
                if (pri_invert)
                        pri_cmp ^= PRI_LT | PRI_EQ | PRI_GT;

                /* 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) {
                                        errno = 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++;

        if (*p == '-') {
                syncfile = 0;
                p++;
        } else
                syncfile = 1;

        switch (*p) {
        case '@':
                {
                        char *tp;
                        char endkey = ':';
                        /*
                         * scan forward to see if there is a port defined.
                         * so we can't use strlcpy..
                         */
                        i = sizeof(f->f_un.f_forw.f_hname);
                        tp = f->f_un.f_forw.f_hname;
                        p++;

                        /*
                         * an ipv6 address should start with a '[' in that case
                         * we should scan for a ']'
                         */
                        if (*p == '[') {
                                p++;
                                endkey = ']';
                        }
                        while (*p && (*p != endkey) && (i-- > 0)) {
                                *tp++ = *p++;
                        }
                        if (endkey == ']' && *p == endkey)
                                p++;
                        *tp = '\0';
                }
                /* See if we copied a domain and have a port */
                if (*p == ':')
                        p++;
                else
                        p = NULL;

                memset(&hints, 0, sizeof(hints));
                hints.ai_family = family;
                hints.ai_socktype = SOCK_DGRAM;
                error = getaddrinfo(f->f_un.f_forw.f_hname,
                                p ? p : "syslog", &hints, &res);
                if (error) {
                        logerror(gai_strerror(error));
                        break;
                }
                f->f_un.f_forw.f_addr = res;
                f->f_type = F_FORW;
                break;

        case '/':
                if ((f->f_file = open(p, logflags, 0600)) < 0) {
                        f->f_type = F_UNUSED;
                        logerror(p);
                        break;
                }
                if (syncfile)
                        f->f_flags |= FFLAG_SYNC;
                if (isatty(f->f_file)) {
                        if (strcmp(p, ctty) == 0)
                                f->f_type = F_CONSOLE;
                        else
                                f->f_type = F_TTY;
                        (void)strlcpy(f->f_un.f_fname, p + sizeof(_PATH_DEV) - 1,
                            sizeof(f->f_un.f_fname));
                } else {
                        (void)strlcpy(f->f_un.f_fname, p, sizeof(f->f_un.f_fname));
                        f->f_type = F_FILE;
                }
                break;

        case '|':
                f->f_un.f_pipe.f_pid = 0;
                (void)strlcpy(f->f_un.f_pipe.f_pname, p + 1,
                    sizeof(f->f_un.f_pipe.f_pname));
                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, MAXLOGNAME - 1);
                        if ((q - p) >= MAXLOGNAME)
                                f->f_un.f_uname[i][MAXLOGNAME - 1] = '\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
 */
static 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);
}

static void
markit(void)
{
        struct filed *f;
        dq_t q, next;

        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 = next) {
                next = 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--;
                }
        }
        MarkSet = 0;
        (void)alarm(TIMERINTVL);
}

/*
 * fork off and become a daemon, but wait for the child to come online
 * before returning to the parent, or we get disk thrashing at boot etc.
 * Set a timer so we don't hang forever if it wedges.
 */
static int
waitdaemon(int nochdir, int noclose, int 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.
 */
static void
timedout(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.
 */
static int
allowaddr(char *s)
{
        char *cp1, *cp2;
        struct allowedpeer ap;
        struct servent *se;
        int masklen = -1;
        struct addrinfo hints, *res;
        struct in_addr *addrp, *maskp;
#ifdef INET6
        int i;
        u_int32_t *addr6p, *mask6p;
#endif
        char ip[NI_MAXHOST];

#ifdef INET6
        if (*s != '[' || (cp1 = strchr(s + 1, ']')) == NULL)
#endif
                cp1 = s;
        if ((cp1 = strrchr(cp1, ':'))) {
                /* service/port provided */
                *cp1++ = '\0';
                if (strlen(cp1) == 1 && *cp1 == '*')
                        /* any port allowed */
                        ap.port = 0;
                else if ((se = getservbyname(cp1, "udp"))) {
                        ap.port = ntohs(se->s_port);
                } else {
                        ap.port = strtol(cp1, &cp2, 0);
                        if (*cp2 != '\0')
                                return (-1); /* port not numeric */
                }
        } else {
                if ((se = getservbyname("syslog", "udp")))
                        ap.port = ntohs(se->s_port);
                else
                        /* sanity, should not happen */
                        ap.port = 514;
        }

        if ((cp1 = strchr(s, '/')) != NULL &&
            strspn(cp1 + 1, "0123456789") == strlen(cp1 + 1)) {
                *cp1 = '\0';
                if ((masklen = atoi(cp1 + 1)) < 0)
                        return (-1);
        }
#ifdef INET6
        if (*s == '[') {
                cp2 = s + strlen(s) - 1;
                if (*cp2 == ']') {
                        ++s;
                        *cp2 = '\0';
                } else {
                        cp2 = NULL;
                }
        } else {
                cp2 = NULL;
        }
#endif
        memset(&hints, 0, sizeof(hints));
        hints.ai_family = PF_UNSPEC;
        hints.ai_socktype = SOCK_DGRAM;
        hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST;
        if (getaddrinfo(s, NULL, &hints, &res) == 0) {
                ap.isnumeric = 1;
                memcpy(&ap.a_addr, res->ai_addr, res->ai_addrlen);
                memset(&ap.a_mask, 0, sizeof(ap.a_mask));
                ap.a_mask.ss_family = res->ai_family;
                if (res->ai_family == AF_INET) {
                        ap.a_mask.ss_len = sizeof(struct sockaddr_in);
                        maskp = &((struct sockaddr_in *)&ap.a_mask)->sin_addr;
                        addrp = &((struct sockaddr_in *)&ap.a_addr)->sin_addr;
                        if (masklen < 0) {
                                /* use default netmask */
                                if (IN_CLASSA(ntohl(addrp->s_addr)))
                                        maskp->s_addr = htonl(IN_CLASSA_NET);
                                else if (IN_CLASSB(ntohl(addrp->s_addr)))
                                        maskp->s_addr = htonl(IN_CLASSB_NET);
                                else
                                        maskp->s_addr = htonl(IN_CLASSC_NET);
                        } else if (masklen <= 32) {
                                /* convert masklen to netmask */
                                if (masklen == 0)
                                        maskp->s_addr = 0;
                                else
                                        maskp->s_addr = htonl(~((1 << (32 - masklen)) - 1));
                        } else {
                                freeaddrinfo(res);
                                return (-1);
                        }
                        /* Lose any host bits in the network number. */
                        addrp->s_addr &= maskp->s_addr;
                }
#ifdef INET6
                else if (res->ai_family == AF_INET6 && masklen <= 128) {
                        ap.a_mask.ss_len = sizeof(struct sockaddr_in6);
                        if (masklen < 0)
                                masklen = 128;
                        mask6p = (u_int32_t *)&((struct sockaddr_in6 *)&ap.a_mask)->sin6_addr;
                        /* convert masklen to netmask */
                        while (masklen > 0) {
                                if (masklen < 32) {
                                        *mask6p = htonl(~(0xffffffff >> masklen));
                                        break;
                                }
                                *mask6p++ = 0xffffffff;
                                masklen -= 32;
                        }
                        /* Lose any host bits in the network number. */
                        mask6p = (u_int32_t *)&((struct sockaddr_in6 *)&ap.a_mask)->sin6_addr;
                        addr6p = (u_int32_t *)&((struct sockaddr_in6 *)&ap.a_addr)->sin6_addr;
                        for (i = 0; i < 4; i++)
                                addr6p[i] &= mask6p[i];
                }
#endif
                else {
                        freeaddrinfo(res);
                        return (-1);
                }
                freeaddrinfo(res);
        } else {
                /* arg `s' is domain name */
                ap.isnumeric = 0;
                ap.a_name = s;
                if (cp1)
                        *cp1 = '/';
#ifdef INET6
                if (cp2) {
                        *cp2 = ']';
                        --s;
                }
#endif
        }

        if (Debug) {
                printf("allowaddr: rule %d: ", NumAllowed);
                if (ap.isnumeric) {
                        printf("numeric, ");
                        getnameinfo((struct sockaddr *)&ap.a_addr,
                                    ((struct sockaddr *)&ap.a_addr)->sa_len,
                                    ip, sizeof ip, NULL, 0, NI_NUMERICHOST);
                        printf("addr = %s, ", ip);
                        getnameinfo((struct sockaddr *)&ap.a_mask,
                                    ((struct sockaddr *)&ap.a_mask)->sa_len,
                                    ip, sizeof ip, NULL, 0, NI_NUMERICHOST);
                        printf("mask = %s; ", ip);
                } else {
                        printf("domainname = %s; ", ap.a_name);
                }
                printf("port = %d\n", ap.port);
        }

        if ((AllowedPeers = realloc(AllowedPeers,
                                    ++NumAllowed * sizeof(struct allowedpeer)))
            == NULL) {
                logerror("realloc");
                exit(1);
        }
        memcpy(&AllowedPeers[NumAllowed - 1], &ap, sizeof(struct allowedpeer));
        return (0);
}

/*
 * Validate that the remote peer has permission to log to us.
 */
static int
validate(struct sockaddr *sa, const char *hname)
{
        int i;
        size_t l1, l2;
        char *cp, name[NI_MAXHOST], ip[NI_MAXHOST], port[NI_MAXSERV];
        struct allowedpeer *ap;
        struct sockaddr_in *sin4, *a4p = NULL, *m4p = NULL;
#ifdef INET6
        int j, reject;
        struct sockaddr_in6 *sin6, *a6p = NULL, *m6p = NULL;
#endif
        struct addrinfo hints, *res;
        u_short sport;

        if (NumAllowed == 0)
                /* traditional behaviour, allow everything */
                return (1);

        (void)strlcpy(name, hname, sizeof(name));
        memset(&hints, 0, sizeof(hints));
        hints.ai_family = PF_UNSPEC;
        hints.ai_socktype = SOCK_DGRAM;
        hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST;
        if (getaddrinfo(name, NULL, &hints, &res) == 0)
                freeaddrinfo(res);
        else if (strchr(name, '.') == NULL) {
                strlcat(name, ".", sizeof name);
                strlcat(name, LocalDomain, sizeof name);
        }
        if (getnameinfo(sa, sa->sa_len, ip, sizeof ip, port, sizeof port,
                        NI_NUMERICHOST | NI_NUMERICSERV) != 0)
                return (0);     /* for safety, should not occur */
        dprintf("validate: dgram from IP %s, port %s, name %s;\n",
                ip, port, name);
        sport = atoi(port);

        /* now, walk down the list */
        for (i = 0, ap = AllowedPeers; i < NumAllowed; i++, ap++) {
                if (ap->port != 0 && ap->port != sport) {
                        dprintf("rejected in rule %d due to port mismatch.\n", i);
                        continue;
                }

                if (ap->isnumeric) {
                        if (ap->a_addr.ss_family != sa->sa_family) {
                                dprintf("rejected in rule %d due to address family mismatch.\n", i);
                                continue;
                        }
                        if (ap->a_addr.ss_family == AF_INET) {
                                sin4 = (struct sockaddr_in *)sa;
                                a4p = (struct sockaddr_in *)&ap->a_addr;
                                m4p = (struct sockaddr_in *)&ap->a_mask;
                                if ((sin4->sin_addr.s_addr & m4p->sin_addr.s_addr)
                                    != a4p->sin_addr.s_addr) {
                                        dprintf("rejected in rule %d due to IP mismatch.\n", i);
                                        continue;
                                }
                        }
#ifdef INET6
                        else if (ap->a_addr.ss_family == AF_INET6) {
                                sin6 = (struct sockaddr_in6 *)sa;
                                a6p = (struct sockaddr_in6 *)&ap->a_addr;
                                m6p = (struct sockaddr_in6 *)&ap->a_mask;
                                if (a6p->sin6_scope_id != 0 &&
                                    sin6->sin6_scope_id != a6p->sin6_scope_id) {
                                        dprintf("rejected in rule %d due to scope mismatch.\n", i);
                                        continue;
                                }
                                reject = 0;
                                for (j = 0; j < 16; j += 4) {
                                        if ((*(u_int32_t *)&sin6->sin6_addr.s6_addr[j] & *(u_int32_t *)&m6p->sin6_addr.s6_addr[j])
                                            != *(u_int32_t *)&a6p->sin6_addr.s6_addr[j]) {
                                                ++reject;
                                                break;
                                        }
                                }
                                if (reject) {
                                        dprintf("rejected in rule %d due to IP mismatch.\n", i);
                                        continue;
                                }
                        }
#endif
                        else
                                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 *.
 */
static int
p_open(const char *prog, pid_t *rpid)
{
        int pfd[2], nulldesc;
        pid_t pid;
        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] = strdup("sh");
                argv[1] = strdup("-c");
                argv[2] = strdup(prog);
                argv[3] = NULL;
                if (argv[0] == NULL || argv[1] == NULL || argv[2] == NULL) {
                        logerror("strdup");
                        exit(1);
                }

                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);
                closefrom(3);

                (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);
        }
        *rpid = pid;
        return (pfd[1]);
}

static void
deadq_enter(pid_t pid, const char *name)
{
        dq_t p;
        int status;

        if (pid == 0)
                return;
        /*
         * 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 == NULL) {
                logerror("malloc");
                exit(1);
        }

        p->dq_pid = pid;
        p->dq_timeout = DQ_TIMO_INIT;
        TAILQ_INSERT_TAIL(&deadq_head, p, dq_entries);
}

static int
deadq_remove(pid_t pid)
{
        dq_t q;

        TAILQ_FOREACH(q, &deadq_head, dq_entries) {
                if (q->dq_pid == pid) {
                        TAILQ_REMOVE(&deadq_head, q, dq_entries);
                                free(q);
                                return (1);
                }
        }

        return (0);
}

static void
log_deadchild(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);
}

static int *
socksetup(int af, char *bindhostname)
{
        struct addrinfo hints, *res, *r;
        const char *bindservice;
        char *cp;
        int error, maxs, *s, *socks;

        /*
         * We have to handle this case for backwards compatibility:
         * If there are two (or more) colons but no '[' and ']',
         * assume this is an inet6 address without a service.
         */
        bindservice = "syslog";
        if (bindhostname != NULL) {
#ifdef INET6
                if (*bindhostname == '[' &&
                    (cp = strchr(bindhostname + 1, ']')) != NULL) {
                        ++bindhostname;
                        *cp = '\0';
                        if (cp[1] == ':' && cp[2] != '\0')
                                bindservice = cp + 2;
                } else {
#endif
                        cp = strchr(bindhostname, ':');
                        if (cp != NULL && strchr(cp + 1, ':') == NULL) {
                                *cp = '\0';
                                if (cp[1] != '\0')
                                        bindservice = cp + 1;
                                if (cp == bindhostname)
                                        bindhostname = NULL;
                        }
#ifdef INET6
                }
#endif
        }

        memset(&hints, 0, sizeof(hints));
        hints.ai_flags = AI_PASSIVE;
        hints.ai_family = af;
        hints.ai_socktype = SOCK_DGRAM;
        error = getaddrinfo(bindhostname, bindservice, &hints, &res);
        if (error) {
                logerror(gai_strerror(error));
                errno = 0;
                die(0);
        }

        /* Count max number of sockets we may open */
        for (maxs = 0, r = res; r; r = r->ai_next, maxs++);
        socks = malloc((maxs+1) * sizeof(int));
        if (socks == NULL) {
                logerror("couldn't allocate memory for sockets");
                die(0);
        }

        *socks = 0;   /* num of sockets counter at start of array */
        s = socks + 1;
        for (r = res; r; r = r->ai_next) {
                int on = 1;
                *s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
                if (*s < 0) {
                        logerror("socket");
                        continue;
                }
#ifdef INET6
                if (r->ai_family == AF_INET6) {
                        if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
                                       (char *)&on, sizeof (on)) < 0) {
                                logerror("setsockopt");
                                close(*s);
                                continue;
                        }
                }
#endif
                if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
                               (char *)&on, sizeof (on)) < 0) {
                        logerror("setsockopt");
                        close(*s);
                        continue;
                }
                /*
                 * RFC 3164 recommends that client side message
                 * should come from the privileged syslogd port.
                 *
                 * If the system administrator choose not to obey
                 * this, we can skip the bind() step so that the
                 * system will choose a port for us.
                 */
                if (!NoBind) {
                        if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
                                logerror("bind");
                                close(*s);
                                continue;
                        }

                        if (!SecureMode)
                                increase_rcvbuf(*s);
                }

                (*socks)++;
                dprintf("socksetup: new socket fd is %d\n", *s);
                s++;
        }

        if (*socks == 0) {
                free(socks);
                if (Debug)
                        return (NULL);
                else
                        die(0);
        }
        if (res)
                freeaddrinfo(res);

        return (socks);
}

static void
increase_rcvbuf(int fd)
{
        socklen_t len, slen;

        slen = sizeof(len);

        if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len, &slen) == 0) {
                if (len < RCVBUF_MINSIZE) {
                        len = RCVBUF_MINSIZE;
                        setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len, sizeof(len));
                }
        }
}