lib/libc/rpc/bindresvport.c

   1 /*
   2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   3  * unrestricted use provided that this legend is included on all tape
   4  * media and as a part of the software program in whole or part.  Users
   5  * may copy or modify Sun RPC without charge, but are not authorized
   6  * to license or distribute it to anyone else except as part of a product or
   7  * program developed by the user.
   8  *
   9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  12  *
  13  * Sun RPC is provided with no support and without any obligation on the
  14  * part of Sun Microsystems, Inc. to assist in its use, correction,
  15  * modification or enhancement.
  16  *
  17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  19  * OR ANY PART THEREOF.
  20  *
  21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  22  * or profits or other special, indirect and consequential damages, even if
  23  * Sun has been advised of the possibility of such damages.
  24  *
  25  * Sun Microsystems, Inc.
  26  * 2550 Garcia Avenue
  27  * Mountain View, California  94043
  28  *
  29  * @(#)bindresvport.c 1.8 88/02/08 SMI
  30  * @(#)bindresvport.c   2.2 88/07/29 4.0 RPCSRC
  31  * $NetBSD: bindresvport.c,v 1.19 2000/07/06 03:03:59 christos Exp $
  32  * $FreeBSD: src/lib/libc/rpc/bindresvport.c,v 1.16 2004/10/16 06:11:34 obrien Exp $
  33  * $DragonFly: src/lib/libc/rpc/bindresvport.c,v 1.4 2005/11/13 12:27:04 swildner Exp $
  34  */
  35
  36 /*
  37  * Copyright (c) 1987 by Sun Microsystems, Inc.
  38  *
  39  * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
  40  */
  41
  42 #include "namespace.h"
  43 #include <sys/types.h>
  44 #include <sys/socket.h>
  45
  46 #include <netinet/in.h>
  47
  48 #include <errno.h>
  49 #include <string.h>
  50 #include <unistd.h>
  51
  52 #include <rpc/rpc.h>
  53
  54 #include <string.h>
  55 #include "un-namespace.h"
  56
  57 /*
  58  * Bind a socket to a privileged IP port
  59  */
  60 int
  61 bindresvport(int sd, struct sockaddr_in *sin)
  62 {
  63         return bindresvport_sa(sd, (struct sockaddr *)sin);
  64 }
  65
  66 /*
  67  * Bind a socket to a privileged IP port
  68  */
  69 int
  70 bindresvport_sa(int sd, struct sockaddr *sa)
  71 {
  72         int old, error, af;
  73         struct sockaddr_storage myaddr;
  74         struct sockaddr_in *sin;
  75 #ifdef INET6
  76         struct sockaddr_in6 *sin6;
  77 #endif
  78         int proto, portrange, portlow;
  79         u_int16_t *portp;
  80         socklen_t salen;
  81
  82         if (sa == NULL) {
  83                 salen = sizeof(myaddr);
  84                 sa = (struct sockaddr *)&myaddr;
  85
  86                 if (_getsockname(sd, sa, &salen) == -1)
  87                         return -1;      /* errno is correctly set */
  88
  89                 af = sa->sa_family;
  90                 memset(sa, 0, salen);
  91         } else
  92                 af = sa->sa_family;
  93
  94         switch (af) {
  95         case AF_INET:
  96                 proto = IPPROTO_IP;
  97                 portrange = IP_PORTRANGE;
  98                 portlow = IP_PORTRANGE_LOW;
  99                 sin = (struct sockaddr_in *)sa;
 100                 salen = sizeof(struct sockaddr_in);
 101                 portp = &sin->sin_port;
 102                 break;
 103 #ifdef INET6
 104         case AF_INET6:
 105                 proto = IPPROTO_IPV6;
 106                 portrange = IPV6_PORTRANGE;
 107                 portlow = IPV6_PORTRANGE_LOW;
 108                 sin6 = (struct sockaddr_in6 *)sa;
 109                 salen = sizeof(struct sockaddr_in6);
 110                 portp = &sin6->sin6_port;
 111                 break;
 112 #endif
 113         default:
 114                 errno = EPFNOSUPPORT;
 115                 return (-1);
 116         }
 117         sa->sa_family = af;
 118         sa->sa_len = salen;
 119
 120         if (*portp == 0) {
 121                 socklen_t oldlen = sizeof(old);
 122
 123                 error = _getsockopt(sd, proto, portrange, &old, &oldlen);
 124                 if (error < 0)
 125                         return (error);
 126
 127                 error = _setsockopt(sd, proto, portrange, &portlow,
 128                     sizeof(portlow));
 129                 if (error < 0)
 130                         return (error);
 131         }
 132
 133         error = _bind(sd, sa, salen);
 134
 135         if (*portp == 0) {
 136                 int saved_errno = errno;
 137
 138                 if (error < 0) {
 139                         if (_setsockopt(sd, proto, portrange, &old,
 140                             sizeof(old)) < 0)
 141                                 errno = saved_errno;
 142                         return (error);
 143                 }
 144
 145                 if (sa != (struct sockaddr *)&myaddr) {
 146                         /* Hmm, what did the kernel assign? */
 147                         if (_getsockname(sd, sa, &salen) < 0)
 148                                 errno = saved_errno;
 149                         return (error);
 150                 }
 151         }
 152         return (error);
 153 }