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[netbsd-mini2440.git] / usr.sbin / lpr / lpd / lpd.c

/*      $NetBSD: lpd.c,v 1.54 2006/01/18 23:17:38 garbled Exp $ */

/*
 * Copyright (c) 1983, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>

#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1983, 1993, 1994\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)lpd.c       8.7 (Berkeley) 5/10/95";
#else
__RCSID("$NetBSD: lpd.c,v 1.54 2006/01/18 23:17:38 garbled Exp $");
#endif
#endif /* not lint */

/*
 * lpd -- line printer daemon.
 *
 * Listen for a connection and perform the requested operation.
 * Operations are:
 *      \1printer\n
 *              check the queue for jobs and print any found.
 *      \2printer\n
 *              receive a job from another machine and queue it.
 *      \3printer [users ...] [jobs ...]\n
 *              return the current state of the queue (short form).
 *      \4printer [users ...] [jobs ...]\n
 *              return the current state of the queue (long form).
 *      \5printer person [users ...] [jobs ...]\n
 *              remove jobs from the queue.
 *
 * Strategy to maintain protected spooling area:
 *      1. Spooling area is writable only by daemon and spooling group
 *      2. lpr runs setuid root and setgrp spooling group; it uses
 *         root to access any file it wants (verifying things before
 *         with an access call) and group id to know how it should
 *         set up ownership of files in the spooling area.
 *      3. Files in spooling area are owned by root, group spooling
 *         group, with mode 660.
 *      4. lpd, lpq and lprm run setuid daemon and setgrp spooling group to
 *         access files and printer.  Users can't get to anything
 *         w/o help of lpq and lprm programs.
 */

#include <sys/param.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/poll.h>
#include <netinet/in.h>

#include <err.h>
#include <netdb.h>
#include <unistd.h>
#include <syslog.h>
#include <signal.h>
#include <errno.h>
#include <fcntl.h>
#include <dirent.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <arpa/inet.h>

#ifdef LIBWRAP
#include <tcpd.h>
#endif

#include "lp.h"
#include "lp.local.h"
#include "pathnames.h"
#include "extern.h"

/* XXX from libc/net/rcmd.c */
extern int __ivaliduser_sa(FILE *, const struct sockaddr *, socklen_t,
                           const char *, const char *);

#ifdef LIBWRAP
int allow_severity = LOG_AUTH|LOG_INFO;
int deny_severity = LOG_AUTH|LOG_WARNING;
#endif

int     lflag;                          /* log requests flag */
int     rflag;                          /* allow of for remote printers */
int     sflag;                          /* secure (no inet) flag */
int     from_remote;                    /* from remote socket */
char    **blist;                        /* list of addresses to bind(2) to */
int     blist_size;
int     blist_addrs;

int                     main(int, char **);
static void             reapchild(int);
static void             mcleanup(int);
static void             doit(void);
static void             startup(void);
static void             chkhost(struct sockaddr *, int);
static void             usage(void);
static struct pollfd    *socksetup(int, int, const char *, int *);

uid_t   uid, euid;
int child_count;

#define LPD_NOPORTCHK   0001            /* skip reserved-port check */

int
main(int argc, char **argv)
{
        struct sockaddr_storage frm;
        socklen_t frmlen;
        sigset_t nmask, omask;
        int lfd, errs, i, f, nfds;
        struct pollfd *socks;
        int child_max = 32;     /* more than enough to hose the system */
        int options = 0, check_options = 0;
        struct servent *sp;
        const char *port = "printer";
        char **newblist;

        euid = geteuid();       /* these shouldn't be different */
        uid = getuid();
        gethostname(host, sizeof(host));
        host[sizeof(host) - 1] = '\0';
        setprogname(*argv);

        errs = 0;
        while ((i = getopt(argc, argv, "b:dln:srw:W")) != -1)
                switch (i) {
                case 'b':
                        if (blist_addrs >= blist_size) {
                                newblist = realloc(blist,
                                    blist_size + sizeof(char *) * 4);
                                if (newblist == NULL)
                                        err(1, "cant allocate bind addr list");
                                blist = newblist;
                                blist_size += sizeof(char *) * 4;
                        }
                        blist[blist_addrs++] = strdup(optarg);
                        break;
                case 'd':
                        options |= SO_DEBUG;
                        break;
                case 'l':
                        lflag++;
                        break;
                case 'n':
                        child_max = atoi(optarg);
                        if (child_max < 0 || child_max > 1024)
                                errx(1, "invalid number of children: %s",
                                    optarg);
                        break;
                case 'r':
                        rflag++;
                        break;
                case 's':
                        sflag++;
                        break;
                case 'w':
                        wait_time = atoi(optarg);
                        if (wait_time < 0)
                                errx(1, "wait time must be postive: %s",
                                    optarg);
                        if (wait_time < 30)
                            warnx("warning: wait time less than 30 seconds");
                        break;
                case 'W':/* allow connections coming from a non-reserved port */
                         /* (done by some lpr-implementations for MS-Windows) */
                        check_options |= LPD_NOPORTCHK;
                        break;
                default:
                        errs++;
                }
        argc -= optind;
        argv += optind;
        if (errs)
                usage();

        switch (argc) {
        case 1:
                if ((i = atoi(argv[0])) == 0)
                        usage();
                if (i < 0 || i > USHRT_MAX)
                        errx(1, "port # %d is invalid", i);

                port = argv[0];
                break;
        case 0:
                sp = getservbyname(port, "tcp");
                if (sp == NULL)
                        errx(1, "%s/tcp: unknown service", port);
                break;
        default:
                usage();
        }

#ifndef DEBUG
        /*
         * Set up standard environment by detaching from the parent.
         */
        daemon(0, 0);
#endif

        openlog("lpd", LOG_PID, LOG_LPR);
        syslog(LOG_INFO, "restarted");
        (void)umask(0);
        lfd = open(_PATH_MASTERLOCK, O_WRONLY|O_CREAT, 0644);
        if (lfd < 0) {
                syslog(LOG_ERR, "%s: %m", _PATH_MASTERLOCK);
                exit(1);
        }
        if (flock(lfd, LOCK_EX|LOCK_NB) < 0) {
                if (errno == EWOULDBLOCK) {     /* active daemon present */
                        syslog(LOG_ERR, "%s is locked; another lpd is running",
                            _PATH_MASTERLOCK);
                        exit(0);
                }
                syslog(LOG_ERR, "%s: %m", _PATH_MASTERLOCK);
                exit(1);
        }
        ftruncate(lfd, 0);
        /*
         * write process id for others to know
         */
        (void)snprintf(line, sizeof(line), "%u\n", getpid());
        f = strlen(line);
        if (write(lfd, line, f) != f) {
                syslog(LOG_ERR, "%s: %m", _PATH_MASTERLOCK);
                exit(1);
        }
        signal(SIGCHLD, reapchild);
        /*
         * Restart all the printers.
         */
        startup();

        sigemptyset(&nmask);
        sigaddset(&nmask, SIGHUP);
        sigaddset(&nmask, SIGINT);
        sigaddset(&nmask, SIGQUIT);
        sigaddset(&nmask, SIGTERM);
        sigprocmask(SIG_BLOCK, &nmask, &omask);

        signal(SIGHUP, mcleanup);
        signal(SIGINT, mcleanup);
        signal(SIGQUIT, mcleanup);
        signal(SIGTERM, mcleanup);

        socks = socksetup(PF_UNSPEC, options, port, &nfds);

        sigprocmask(SIG_SETMASK, &omask, (sigset_t *)0);

        if (blist != NULL) {
                for (i = 0; i < blist_addrs; i++)
                        free(blist[i]);
                free(blist);
        }

        /*
         * Main loop: accept, do a request, continue.
         */
        memset(&frm, 0, sizeof(frm));
        for (;;) {
                int rv, s;
                /* "short" so it overflows in about 2 hours */
                struct timespec sleeptime = {10, 0};

                while (child_max < child_count) {
                        syslog(LOG_WARNING,
                            "too many children, sleeping for %ld seconds",
                                (long)sleeptime.tv_sec);
                        nanosleep(&sleeptime, NULL);
                        sleeptime.tv_sec <<= 1;
                        if (sleeptime.tv_sec <= 0) {
                                syslog(LOG_CRIT, "sleeptime overflowed! help!");
                                sleeptime.tv_sec = 10;
                        }
                }

                rv = poll(socks, nfds, INFTIM);
                if (rv <= 0) {
                        if (rv < 0 && errno != EINTR)
                                syslog(LOG_WARNING, "poll: %m");
                        continue;
                }
                s = -1;
                for (i = 0; i < nfds; i++) 
                        if (socks[i].revents & POLLIN) {
                                frmlen = sizeof(frm);
                                s = accept(socks[i].fd,
                                    (struct sockaddr *)&frm, &frmlen);
                                break;
                        }
                if (s < 0) {
                        if (errno != EINTR)
                                syslog(LOG_WARNING, "accept: %m");
                        continue;
                }
                
                switch (fork()) {
                case 0:
                        signal(SIGCHLD, SIG_DFL);
                        signal(SIGHUP, SIG_IGN);
                        signal(SIGINT, SIG_IGN);
                        signal(SIGQUIT, SIG_IGN);
                        signal(SIGTERM, SIG_IGN);
                        for (i = 0; i < nfds; i++) 
                                (void)close(socks[i].fd);
                        dup2(s, STDOUT_FILENO);
                        (void)close(s);
                        if (frm.ss_family != AF_LOCAL) {
                                /* for both AF_INET and AF_INET6 */
                                from_remote = 1;
                                chkhost((struct sockaddr *)&frm, check_options);
                        } else
                                from_remote = 0;
                        doit();
                        exit(0);
                case -1:
                        syslog(LOG_WARNING, "fork: %m, sleeping for 10 seconds...");
                        sleep(10);
                        continue;
                default:
                        child_count++;
                }
                (void)close(s);
        }
}

static void
reapchild(int signo)
{
        union wait status;

        while (wait3((int *)&status, WNOHANG, 0) > 0)
                child_count--;
}

static void
mcleanup(int signo)
{
        if (lflag)
                syslog(LOG_INFO, "exiting");
        unlink(_PATH_SOCKETNAME);
        exit(0);
}

/*
 * Stuff for handling job specifications
 */
char    *user[MAXUSERS];        /* users to process */
int     users;                  /* # of users in user array */
int     requ[MAXREQUESTS];      /* job number of spool entries */
int     requests;               /* # of spool requests */
char    *person;                /* name of person doing lprm */

char    fromb[NI_MAXHOST];      /* buffer for client's machine name */
char    cbuf[BUFSIZ];           /* command line buffer */
const char *cmdnames[] = {
        "null",
        "printjob",
        "recvjob",
        "displayq short",
        "displayq long",
        "rmjob"
};

static void
doit(void)
{
        char *cp;
        int n;

        for (;;) {
                cp = cbuf;
                do {
                        if (cp >= &cbuf[sizeof(cbuf) - 1])
                                fatal("Command line too long");
                        if ((n = read(STDOUT_FILENO, cp, 1)) != 1) {
                                if (n < 0)
                                        fatal("Lost connection");
                                return;
                        }
                } while (*cp++ != '\n');
                *--cp = '\0';
                cp = cbuf;
                if (lflag) {
                        if (*cp >= '\1' && *cp <= '\5') {
                                syslog(LOG_INFO, "%s requests %s %s",
                                        from, cmdnames[(int)*cp], cp+1);
                                setproctitle("serving %s: %s %s", from,
                                    cmdnames[(int)*cp], cp+1);
                        }
                        else
                                syslog(LOG_INFO, "bad request (%d) from %s",
                                        *cp, from);
                }
                switch (*cp++) {
                case '\1':      /* check the queue and print any jobs there */
                        printer = cp;
                        if (*printer == '\0')
                                printer = DEFLP;
                        printjob();
                        break;
                case '\2':      /* receive files to be queued */
                        if (!from_remote) {
                                syslog(LOG_INFO, "illegal request (%d)", *cp);
                                exit(1);
                        }
                        printer = cp;
                        if (*printer == '\0')
                                printer = DEFLP;
                        recvjob();
                        break;
                case '\3':      /* display the queue (short form) */
                case '\4':      /* display the queue (long form) */
                        printer = cp;
                        if (*printer == '\0')
                                printer = DEFLP;
                        while (*cp) {
                                if (*cp != ' ') {
                                        cp++;
                                        continue;
                                }
                                *cp++ = '\0';
                                while (isspace((unsigned char)*cp))
                                        cp++;
                                if (*cp == '\0')
                                        break;
                                if (isdigit((unsigned char)*cp)) {
                                        if (requests >= MAXREQUESTS)
                                                fatal("Too many requests");
                                        requ[requests++] = atoi(cp);
                                } else {
                                        if (users >= MAXUSERS)
                                                fatal("Too many users");
                                        user[users++] = cp;
                                }
                        }
                        displayq(cbuf[0] - '\3');
                        exit(0);
                case '\5':      /* remove a job from the queue */
                        if (!from_remote) {
                                syslog(LOG_INFO, "illegal request (%d)", *cp);
                                exit(1);
                        }
                        printer = cp;
                        if (*printer == '\0')
                                printer = DEFLP;
                        while (*cp && *cp != ' ')
                                cp++;
                        if (!*cp)
                                break;
                        *cp++ = '\0';
                        person = cp;
                        while (*cp) {
                                if (*cp != ' ') {
                                        cp++;
                                        continue;
                                }
                                *cp++ = '\0';
                                while (isspace((unsigned char)*cp))
                                        cp++;
                                if (*cp == '\0')
                                        break;
                                if (isdigit((unsigned char)*cp)) {
                                        if (requests >= MAXREQUESTS)
                                                fatal("Too many requests");
                                        requ[requests++] = atoi(cp);
                                } else {
                                        if (users >= MAXUSERS)
                                                fatal("Too many users");
                                        user[users++] = cp;
                                }
                        }
                        rmjob();
                        break;
                }
                fatal("Illegal service request");
        }
}

/*
 * Make a pass through the printcap database and start printing any
 * files left from the last time the machine went down.
 */
static void
startup(void)
{
        char *buf;
        char *cp;

        /*
         * Restart the daemons.
         */
        while (cgetnext(&buf, printcapdb) > 0) {
                if (ckqueue(buf) <= 0) {
                        free(buf);
                        continue;       /* no work to do for this printer */
                }
                for (cp = buf; *cp; cp++)
                        if (*cp == '|' || *cp == ':') {
                                *cp = '\0';
                                break;
                        }
                if (lflag)
                        syslog(LOG_INFO, "work for %s", buf);
                switch (fork()) {
                case -1:
                        syslog(LOG_WARNING, "startup: cannot fork");
                        mcleanup(0);
                case 0:
                        printer = buf;
                        setproctitle("working on printer %s", printer);
                        cgetclose();
                        printjob();
                        /* NOTREACHED */
                default:
                        child_count++;
                        free(buf);
                }
        }
}

#define DUMMY ":nobody::"

/*
 * Check to see if the from host has access to the line printer.
 */
static void
chkhost(struct sockaddr *f, int check_opts)
{
        struct addrinfo hints, *res, *r;
        FILE *hostf;
        int good = 0;
        char hst[NI_MAXHOST], ip[NI_MAXHOST];
        char serv[NI_MAXSERV];
        int error;
#ifdef LIBWRAP
        struct request_info req;
#endif

        error = getnameinfo(f, f->sa_len, NULL, 0, serv, sizeof(serv),
                            NI_NUMERICSERV);
        if (error)
                fatal("Malformed from address: %s", gai_strerror(error));

         if (!(check_opts & LPD_NOPORTCHK) &&
               atoi(serv) >= IPPORT_RESERVED)
                fatal("Connect from invalid port (%s)", serv);

        /* Need real hostname for temporary filenames */
        error = getnameinfo(f, f->sa_len, hst, sizeof(hst), NULL, 0,
                            NI_NAMEREQD);
        if (error) {
                error = getnameinfo(f, f->sa_len, hst, sizeof(hst), NULL, 0,
                                    NI_NUMERICHOST);
                if (error)
                        fatal("Host name for your address unknown");
                else
                        fatal("Host name for your address (%s) unknown", hst);
        }

        (void)strlcpy(fromb, hst, sizeof(fromb));
        from = fromb;

        /* need address in stringform for comparison (no DNS lookup here) */
        error = getnameinfo(f, f->sa_len, hst, sizeof(hst), NULL, 0,
                            NI_NUMERICHOST);
        if (error)
                fatal("Cannot print address");

        /* Check for spoof, ala rlogind */
        memset(&hints, 0, sizeof(hints));
        hints.ai_family = PF_UNSPEC;
        hints.ai_socktype = SOCK_DGRAM; /*dummy*/
        error = getaddrinfo(fromb, NULL, &hints, &res);
        if (error) {
                fatal("hostname for your address (%s) unknown: %s", hst,
                    gai_strerror(error));
        }
        good = 0;
        for (r = res; good == 0 && r; r = r->ai_next) {
                error = getnameinfo(r->ai_addr, r->ai_addrlen, ip, sizeof(ip),
                                    NULL, 0, NI_NUMERICHOST);
                if (!error && !strcmp(hst, ip))
                        good = 1;
        }
        if (res)
                freeaddrinfo(res);
        if (good == 0)
                fatal("address for your hostname (%s) not matched", hst);

        setproctitle("serving %s", from);

#ifdef LIBWRAP
        request_init(&req, RQ_DAEMON, "lpd", RQ_CLIENT_SIN, f,
            RQ_FILE, STDOUT_FILENO, NULL);
        fromhost(&req);
        if (!hosts_access(&req))
                goto denied;
#endif

        hostf = fopen(_PATH_HOSTSEQUIV, "r");
        if (hostf) {
                if (__ivaliduser_sa(hostf, f, f->sa_len, DUMMY, DUMMY) == 0) {
                        (void)fclose(hostf);
                        return;
                }
                (void)fclose(hostf);
        }
        hostf = fopen(_PATH_HOSTSLPD, "r");
        if (hostf) {
                if (__ivaliduser_sa(hostf, f, f->sa_len, DUMMY, DUMMY) == 0) {
                        (void)fclose(hostf);
                        return;
                }
                (void)fclose(hostf);
        }
#ifdef LIBWRAP
  denied:
#endif
        fatal("Your host does not have line printer access");
        /*NOTREACHED*/
}


static void
usage(void)
{

        (void)fprintf(stderr,
            "Usage: %s [-dlrsW] [-b bind-address] [-n maxchild] "
            "[-w maxwait] [port]\n", getprogname());
        exit(1);
}

/* setup server socket for specified address family */
/* if af is PF_UNSPEC more than one socket may be returned */
/* the returned list is dynamically allocated, so caller needs to free it */
struct pollfd *
socksetup(int af, int options, const char *port, int *nfds)
{
        struct sockaddr_un un;
        struct addrinfo hints, *res, *r;
        int error, s, blidx = 0, n;
        struct pollfd *socks, *newsocks;
        const int on = 1;

        *nfds = 0;

        socks = malloc(1 * sizeof(socks[0]));
        if (!socks) {
                syslog(LOG_ERR, "couldn't allocate memory for sockets");
                mcleanup(0);
        }

        s = socket(AF_LOCAL, SOCK_STREAM, 0);
        if (s < 0) {
                syslog(LOG_ERR, "socket(): %m");
                exit(1);
        }
        memset(&un, 0, sizeof(un));
        un.sun_family = AF_LOCAL;
        strncpy(un.sun_path, _PATH_SOCKETNAME, sizeof(un.sun_path) - 1);
        un.sun_len = SUN_LEN(&un);
        (void)umask(07);
        (void)unlink(_PATH_SOCKETNAME);
        if (bind(s, (struct sockaddr *)&un, un.sun_len) < 0) {
                syslog(LOG_ERR, "bind(): %m");
                exit(1);
        }
        (void)umask(0);
        listen(s, 5);
        socks[*nfds].fd = s;
        socks[*nfds].events = POLLIN;
        (*nfds)++;

        if (sflag && !blist_addrs)
                return (socks);

        do {
                memset(&hints, 0, sizeof(hints));
                hints.ai_flags = AI_PASSIVE;
                hints.ai_family = af;
                hints.ai_socktype = SOCK_STREAM;
                error = getaddrinfo((blist_addrs == 0) ? NULL : blist[blidx],
                    port ? port : "printer", &hints, &res);
                if (error) {
                        if (blist_addrs)
                                syslog(LOG_ERR, "%s: %s", blist[blidx],
                                    gai_strerror(error));
                        else
                                syslog(LOG_ERR, "%s", gai_strerror(error));
                        mcleanup(0);
                }

                /* Count max number of sockets we may open */
                for (r = res, n = 0; r; r = r->ai_next, n++)
                        ;
                newsocks = realloc(socks, (*nfds + n) * sizeof(socks[0]));
                if (!newsocks) {
                        syslog(LOG_ERR, "couldn't allocate memory for sockets");
                        mcleanup(0);
                }
                socks = newsocks;

                for (r = res; r; r = r->ai_next) {
                        s = socket(r->ai_family, r->ai_socktype,
                            r->ai_protocol);
                        if (s < 0) {
                                syslog(LOG_DEBUG, "socket(): %m");
                                continue;
                        }
                        if (options & SO_DEBUG)
                                if (setsockopt(s, SOL_SOCKET, SO_DEBUG,
                                               &on, sizeof(on)) < 0) {
                                        syslog(LOG_ERR,
                                               "setsockopt (SO_DEBUG): %m");
                                        close(s);
                                        continue;
                                }
                        if (setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &on,
                            sizeof(on)) < 0) {
                                syslog(LOG_ERR,
                                    "setsockopt (SO_REUSEPORT): %m");
                                close(s);
                                continue;
                        }
                        if (r->ai_family == AF_INET6 && setsockopt(s,
                            IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) {
                                syslog(LOG_ERR,
                                    "setsockopt (IPV6_V6ONLY): %m");
                                close(s);
                                continue;
                        }
                        if (bind(s, r->ai_addr, r->ai_addrlen) < 0) {
                                syslog(LOG_DEBUG, "bind(): %m");
                                close(s);
                                continue;
                        }
                        listen(s, 5);
                        socks[*nfds].fd = s;
                        socks[*nfds].events = POLLIN;
                        (*nfds)++;
                }

                if (res)
                        freeaddrinfo(res);
        } while (++blidx < blist_addrs);

        return (socks);
}