lib/libc/rpc/bindresvport.c

   1 /*      $NetBSD: bindresvport.c,v 1.25 2013/03/11 20:19:28 tron Exp $   */
   2
   3 /*
   4  * Copyright (c) 2010, Oracle America, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met:
   9  *
  10  *     * Redistributions of source code must retain the above copyright
  11  *       notice, this list of conditions and the following disclaimer.
  12  *     * Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials
  15  *       provided with the distribution.
  16  *     * Neither the name of the "Oracle America, Inc." nor the names of its
  17  *       contributors may be used to endorse or promote products derived
  18  *       from this software without specific prior written permission.
  19  *
  20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <sys/cdefs.h>
  35 #if defined(LIBC_SCCS) && !defined(lint)
  36 #if 0
  37 static char *sccsid = "@(#)bindresvport.c 1.8 88/02/08 SMI";
  38 static char *sccsid = "@(#)bindresvport.c       2.2 88/07/29 4.0 RPCSRC";
  39 #else
  40 __RCSID("$NetBSD: bindresvport.c,v 1.25 2013/03/11 20:19:28 tron Exp $");
  41 #endif
  42 #endif
  43
  44 /*
  45  * Copyright (c) 1987 by Sun Microsystems, Inc.
  46  */
  47
  48 #include "namespace.h"
  49
  50 #include <sys/types.h>
  51 #include <sys/socket.h>
  52
  53 #include <netinet/in.h>
  54
  55 #include <errno.h>
  56 #include <string.h>
  57 #include <unistd.h>
  58
  59 #include <rpc/rpc.h>
  60 #include "svc_fdset.h"
  61
  62 #ifdef __weak_alias
  63 __weak_alias(bindresvport,_bindresvport)
  64 __weak_alias(bindresvport_sa,_bindresvport_sa)
  65 #endif
  66
  67 /*
  68  * Bind a socket to a privileged IP port
  69  */
  70 int
  71 bindresvport(int sd, struct sockaddr_in *brsin)
  72 {
  73         return bindresvport_sa(sd, (struct sockaddr *)(void *)brsin);
  74 }
  75
  76 /*
  77  * Bind a socket to a privileged IP port
  78  */
  79 int
  80 bindresvport_sa(int sd, struct sockaddr *sa)
  81 {
  82         int error, old;
  83         struct sockaddr_storage myaddr;
  84         struct sockaddr_in *brsin;
  85 #ifdef INET6
  86         struct sockaddr_in6 *brsin6;
  87 #endif
  88         int proto, portrange, portlow;
  89         u_int16_t *portp;
  90         socklen_t salen;
  91         int af;
  92
  93         if (sa == NULL) {
  94                 salen = sizeof(myaddr);
  95                 sa = (struct sockaddr *)(void *)&myaddr;
  96
  97                 if (getsockname(sd, sa, &salen) == -1)
  98                         return -1;      /* errno is correctly set */
  99
 100                 af = sa->sa_family;
 101                 memset(sa, 0, salen);
 102         } else
 103                 af = sa->sa_family;
 104
 105         switch (af) {
 106         case AF_INET:
 107                 proto = IPPROTO_IP;
 108                 portrange = IP_PORTRANGE;
 109                 portlow = IP_PORTRANGE_LOW;
 110                 brsin = (struct sockaddr_in *)(void *)sa;
 111                 salen = sizeof(struct sockaddr_in);
 112                 portp = &brsin->sin_port;
 113                 break;
 114 #ifdef INET6
 115         case AF_INET6:
 116                 proto = IPPROTO_IPV6;
 117                 portrange = IPV6_PORTRANGE;
 118                 portlow = IPV6_PORTRANGE_LOW;
 119                 brsin6 = (struct sockaddr_in6 *)(void *)sa;
 120                 salen = sizeof(struct sockaddr_in6);
 121                 portp = &brsin6->sin6_port;
 122                 break;
 123 #endif
 124         default:
 125                 errno = EPFNOSUPPORT;
 126                 return (-1);
 127         }
 128         sa->sa_family = af;
 129         sa->sa_len = salen;
 130
 131         if (*portp == 0) {
 132                 socklen_t oldlen = sizeof(old);
 133
 134                 error = getsockopt(sd, proto, portrange, &old, &oldlen);
 135                 if (error < 0)
 136                         return (error);
 137                 error = setsockopt(sd, proto, portrange, &portlow,
 138                     (socklen_t)sizeof(portlow));
 139                 if (error < 0)
 140                         return (error);
 141         }
 142
 143         error = bind(sd, sa, salen);
 144
 145         if (*portp == 0) {
 146                 int saved_errno = errno;
 147
 148                 if (error < 0) {
 149                         if (setsockopt(sd, proto, portrange, &old,
 150                             (socklen_t)sizeof(old)) < 0)
 151                                 errno = saved_errno;
 152                         return (error);
 153                 }
 154
 155                 if (sa != (struct sockaddr *)(void *)&myaddr) {
 156                         /* What did the kernel assign? */
 157                         if (getsockname(sd, sa, &salen) < 0)
 158                                 errno = saved_errno;
 159                         return (error);
 160                 }
 161         }
 162         return (error);
 163 }