1 /* $NetBSD: bindresvport.c,v 1.19 2000/07/06 03:03:59 christos Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-3-Clause 5 * 6 * Copyright (c) 2009, Sun Microsystems, Inc. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions are met: 11 * - Redistributions of source code must retain the above copyright notice, 12 * this list of conditions and the following disclaimer. 13 * - Redistributions in binary form must reproduce the above copyright notice, 14 * this list of conditions and the following disclaimer in the documentation 15 * and/or other materials provided with the distribution. 16 * - Neither the name of Sun Microsystems, 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 "AS IS" 21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* from: $OpenBSD: bindresvport.c,v 1.7 1996/07/30 16:25:47 downsj Exp $ */ 34 /* 35 * Copyright (c) 1987 by Sun Microsystems, Inc. 36 * 37 * Portions Copyright(C) 1996, Jason Downs. All rights reserved. 38 */ 39 40 #include "namespace.h" 41 #include <sys/types.h> 42 #include <sys/socket.h> 43 44 #include <netinet/in.h> 45 46 #include <errno.h> 47 #include <string.h> 48 #include <unistd.h> 49 50 #include <rpc/rpc.h> 51 52 #include <string.h> 53 #include "un-namespace.h" 54 55 /* 56 * Bind a socket to a privileged IP port 57 */ 58 int 59 bindresvport(int sd, struct sockaddr_in *sin) 60 { 61 return bindresvport_sa(sd, (struct sockaddr *)sin); 62 } 63 64 /* 65 * Bind a socket to a privileged IP port 66 */ 67 int 68 bindresvport_sa(int sd, struct sockaddr *sa) 69 { 70 int old, error, af; 71 struct sockaddr_storage myaddr; 72 struct sockaddr_in *sin; 73 #ifdef INET6 74 struct sockaddr_in6 *sin6; 75 #endif 76 int proto, portrange, portlow; 77 u_int16_t *portp; 78 socklen_t salen; 79 80 if (sa == NULL) { 81 salen = sizeof(myaddr); 82 sa = (struct sockaddr *)&myaddr; 83 84 if (_getsockname(sd, sa, &salen) == -1) 85 return -1; /* errno is correctly set */ 86 87 af = sa->sa_family; 88 memset(sa, 0, salen); 89 } else 90 af = sa->sa_family; 91 92 switch (af) { 93 case AF_INET: 94 proto = IPPROTO_IP; 95 portrange = IP_PORTRANGE; 96 portlow = IP_PORTRANGE_LOW; 97 sin = (struct sockaddr_in *)sa; 98 salen = sizeof(struct sockaddr_in); 99 portp = &sin->sin_port; 100 break; 101 #ifdef INET6 102 case AF_INET6: 103 proto = IPPROTO_IPV6; 104 portrange = IPV6_PORTRANGE; 105 portlow = IPV6_PORTRANGE_LOW; 106 sin6 = (struct sockaddr_in6 *)sa; 107 salen = sizeof(struct sockaddr_in6); 108 portp = &sin6->sin6_port; 109 break; 110 #endif 111 default: 112 errno = EPFNOSUPPORT; 113 return (-1); 114 } 115 sa->sa_family = af; 116 sa->sa_len = salen; 117 118 if (*portp == 0) { 119 socklen_t oldlen = sizeof(old); 120 121 error = _getsockopt(sd, proto, portrange, &old, &oldlen); 122 if (error < 0) 123 return (error); 124 125 error = _setsockopt(sd, proto, portrange, &portlow, 126 sizeof(portlow)); 127 if (error < 0) 128 return (error); 129 } 130 131 error = _bind(sd, sa, salen); 132 133 if (*portp == 0) { 134 int saved_errno = errno; 135 136 if (error < 0) { 137 if (_setsockopt(sd, proto, portrange, &old, 138 sizeof(old)) < 0) 139 errno = saved_errno; 140 return (error); 141 } 142 143 if (sa != (struct sockaddr *)&myaddr) { 144 /* Hmm, what did the kernel assign? */ 145 if (_getsockname(sd, sa, &salen) < 0) 146 errno = saved_errno; 147 return (error); 148 } 149 } 150 return (error); 151 } 152