1 /* $OpenBSD: monitor_fdpass.c,v 1.12 2006/08/03 03:34:42 deraadt Exp $ */ 2 /* 3 * Copyright 2001 Niels Provos <provos@citi.umich.edu> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include "includes.h" 28 29 #include <sys/types.h> 30 #include <sys/socket.h> 31 #include <sys/uio.h> 32 #ifdef HAVE_SYS_UN_H 33 #include <sys/un.h> 34 #endif 35 36 #include <errno.h> 37 #include <string.h> 38 #include <stdarg.h> 39 40 #include "log.h" 41 #include "monitor_fdpass.h" 42 43 void 44 mm_send_fd(int sock, int fd) 45 { 46 #if defined(HAVE_SENDMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) 47 struct msghdr msg; 48 struct iovec vec; 49 char ch = '\0'; 50 ssize_t n; 51 #ifndef HAVE_ACCRIGHTS_IN_MSGHDR 52 char tmp[CMSG_SPACE(sizeof(int))]; 53 struct cmsghdr *cmsg; 54 #endif 55 56 memset(&msg, 0, sizeof(msg)); 57 #ifdef HAVE_ACCRIGHTS_IN_MSGHDR 58 msg.msg_accrights = (caddr_t)&fd; 59 msg.msg_accrightslen = sizeof(fd); 60 #else 61 msg.msg_control = (caddr_t)tmp; 62 msg.msg_controllen = CMSG_LEN(sizeof(int)); 63 cmsg = CMSG_FIRSTHDR(&msg); 64 cmsg->cmsg_len = CMSG_LEN(sizeof(int)); 65 cmsg->cmsg_level = SOL_SOCKET; 66 cmsg->cmsg_type = SCM_RIGHTS; 67 *(int *)CMSG_DATA(cmsg) = fd; 68 #endif 69 70 vec.iov_base = &ch; 71 vec.iov_len = 1; 72 msg.msg_iov = &vec; 73 msg.msg_iovlen = 1; 74 75 if ((n = sendmsg(sock, &msg, 0)) == -1) 76 fatal("%s: sendmsg(%d): %s", __func__, fd, 77 strerror(errno)); 78 if (n != 1) 79 fatal("%s: sendmsg: expected sent 1 got %ld", 80 __func__, (long)n); 81 #else 82 fatal("%s: UsePrivilegeSeparation=yes not supported", 83 __func__); 84 #endif 85 } 86 87 int 88 mm_receive_fd(int sock) 89 { 90 #if defined(HAVE_RECVMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) 91 struct msghdr msg; 92 struct iovec vec; 93 ssize_t n; 94 char ch; 95 int fd; 96 #ifndef HAVE_ACCRIGHTS_IN_MSGHDR 97 char tmp[CMSG_SPACE(sizeof(int))]; 98 struct cmsghdr *cmsg; 99 #endif 100 101 memset(&msg, 0, sizeof(msg)); 102 vec.iov_base = &ch; 103 vec.iov_len = 1; 104 msg.msg_iov = &vec; 105 msg.msg_iovlen = 1; 106 #ifdef HAVE_ACCRIGHTS_IN_MSGHDR 107 msg.msg_accrights = (caddr_t)&fd; 108 msg.msg_accrightslen = sizeof(fd); 109 #else 110 msg.msg_control = tmp; 111 msg.msg_controllen = sizeof(tmp); 112 #endif 113 114 if ((n = recvmsg(sock, &msg, 0)) == -1) 115 fatal("%s: recvmsg: %s", __func__, strerror(errno)); 116 if (n != 1) 117 fatal("%s: recvmsg: expected received 1 got %ld", 118 __func__, (long)n); 119 120 #ifdef HAVE_ACCRIGHTS_IN_MSGHDR 121 if (msg.msg_accrightslen != sizeof(fd)) 122 fatal("%s: no fd", __func__); 123 #else 124 cmsg = CMSG_FIRSTHDR(&msg); 125 if (cmsg == NULL) 126 fatal("%s: no message header", __func__); 127 #ifndef BROKEN_CMSG_TYPE 128 if (cmsg->cmsg_type != SCM_RIGHTS) 129 fatal("%s: expected type %d got %d", __func__, 130 SCM_RIGHTS, cmsg->cmsg_type); 131 #endif 132 fd = (*(int *)CMSG_DATA(cmsg)); 133 #endif 134 return fd; 135 #else 136 fatal("%s: UsePrivilegeSeparation=yes not supported", 137 __func__); 138 #endif 139 } 140