sbin/mount_portal/pt_tcp.c

   1 /*      $NetBSD: pt_tcp.c,v 1.20 2007/07/02 18:07:45 pooka Exp $        */
   2
   3 /*
   4  * Copyright (c) 1992, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software donated to Berkeley by
   8  * Jan-Simon Pendry.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      from: Id: pt_tcp.c,v 1.1 1992/05/25 21:43:09 jsp Exp
  35  *      @(#)pt_tcp.c    8.5 (Berkeley) 4/28/95
  36  */
  37
  38 #include <sys/cdefs.h>
  39 #ifndef lint
  40 __RCSID("$NetBSD: pt_tcp.c,v 1.20 2007/07/02 18:07:45 pooka Exp $");
  41 #endif /* not lint */
  42
  43 #include <stdio.h>
  44 #include <unistd.h>
  45 #include <stdlib.h>
  46 #include <errno.h>
  47 #include <string.h>
  48 #include <sys/types.h>
  49 #include <sys/param.h>
  50 #include <sys/syslog.h>
  51 #include <sys/socket.h>
  52 #include <netinet/in.h>
  53 #include <arpa/inet.h>
  54 #include <netdb.h>
  55
  56 #include "portald.h"
  57
  58 /*
  59  * Key will be tcp/host/port[/"priv"]
  60  * Create a TCP socket connected to the
  61  * requested host and port.
  62  * Some trailing suffix values have special meanings.
  63  * An unrecognised suffix is an error.
  64  */
  65 int
  66 portal_tcp(struct portal_cred *pcr, char *key, char **v, int *fdp)
  67 {
  68         char host[MAXHOSTNAMELEN];
  69         char port[MAXHOSTNAMELEN];
  70         char *p = key + (v[1] ? strlen(v[1]) : 0);
  71         char *q;
  72         int priv = 0;
  73         struct addrinfo hints, *res, *lres;
  74         int so = -1;
  75         const char *cause = "unknown";
  76
  77         q = strchr(p, '/');
  78         if (q == 0 || (size_t)(q - p) >= sizeof(host))
  79                 return (EINVAL);
  80         *q = '\0';
  81         if (strlcpy(host, p, sizeof(host)) >= sizeof(host))
  82                 return (EINVAL);
  83         p = q + 1;
  84
  85         q = strchr(p, '/');
  86         if (q)
  87                 *q = '\0';
  88         if (strlcpy(port, p, sizeof(port)) >= sizeof(port))
  89                 return (EINVAL);
  90         if (q) {
  91                 p = q + 1;
  92                 if (strcmp(p, "priv") == 0) {
  93                         if (pcr->pcr_uid == 0)
  94                                 priv = 1;
  95                         else
  96                                 return (EPERM);
  97                 } else {
  98                         return (EINVAL);
  99                 }
 100         }
 101
 102         memset(&hints, 0, sizeof(hints));
 103         hints.ai_family = PF_UNSPEC;
 104         hints.ai_socktype = SOCK_STREAM;
 105         hints.ai_protocol = 0;
 106         if (getaddrinfo(host, port, &hints, &res) != 0)
 107                 return(EINVAL);
 108
 109         for (lres = res; lres; lres = lres->ai_next) {
 110                 if (priv)
 111                         so = rresvport((int *) 0);
 112                 else
 113                         so = socket(lres->ai_family, lres->ai_socktype,
 114                             lres->ai_protocol);
 115                 if (so < 0) {
 116                         cause = "socket";
 117                         continue;
 118                 }
 119
 120                 if (connect(so, lres->ai_addr, lres->ai_addrlen) != 0) {
 121                         cause = "connect";
 122                         (void)close(so);
 123                         so = -1;
 124                         continue;
 125                 }
 126
 127                 *fdp = so;
 128                 errno = 0;
 129                 break;
 130         }
 131
 132         if (so < 0)
 133                 syslog(LOG_WARNING, "%s: %m", cause);
 134
 135         freeaddrinfo(res);
 136
 137         return (errno);
 138 }