1 /* 2 * Copyright 2001 Niels Provos <provos@citi.umich.edu> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "includes.h" 27 RCSID("$OpenBSD: monitor_fdpass.c,v 1.2 2002/03/24 17:53:16 stevesk Exp $"); 28 29 #include <sys/uio.h> 30 31 #include "log.h" 32 #include "monitor_fdpass.h" 33 34 void 35 mm_send_fd(int socket, int fd) 36 { 37 struct msghdr msg; 38 char tmp[CMSG_SPACE(sizeof(int))]; 39 struct cmsghdr *cmsg; 40 struct iovec vec; 41 char ch = '\0'; 42 int n; 43 44 memset(&msg, 0, sizeof(msg)); 45 msg.msg_control = (caddr_t)tmp; 46 msg.msg_controllen = CMSG_LEN(sizeof(int)); 47 cmsg = CMSG_FIRSTHDR(&msg); 48 cmsg->cmsg_len = CMSG_LEN(sizeof(int)); 49 cmsg->cmsg_level = SOL_SOCKET; 50 cmsg->cmsg_type = SCM_RIGHTS; 51 *(int *)CMSG_DATA(cmsg) = fd; 52 53 vec.iov_base = &ch; 54 vec.iov_len = 1; 55 msg.msg_iov = &vec; 56 msg.msg_iovlen = 1; 57 58 if ((n = sendmsg(socket, &msg, 0)) == -1) 59 fatal("%s: sendmsg(%d): %s", __FUNCTION__, fd, 60 strerror(errno)); 61 if (n != 1) 62 fatal("%s: sendmsg: expected sent 1 got %d", 63 __FUNCTION__, n); 64 } 65 66 int 67 mm_receive_fd(int socket) 68 { 69 struct msghdr msg; 70 char tmp[CMSG_SPACE(sizeof(int))]; 71 struct cmsghdr *cmsg; 72 struct iovec vec; 73 char ch; 74 int fd, n; 75 76 memset(&msg, 0, sizeof(msg)); 77 vec.iov_base = &ch; 78 vec.iov_len = 1; 79 msg.msg_iov = &vec; 80 msg.msg_iovlen = 1; 81 msg.msg_control = tmp; 82 msg.msg_controllen = sizeof(tmp); 83 84 if ((n = recvmsg(socket, &msg, 0)) == -1) 85 fatal("%s: recvmsg: %s", __FUNCTION__, strerror(errno)); 86 if (n != 1) 87 fatal("%s: recvmsg: expected received 1 got %d", 88 __FUNCTION__, n); 89 90 cmsg = CMSG_FIRSTHDR(&msg); 91 if (cmsg->cmsg_type != SCM_RIGHTS) 92 fatal("%s: expected type %d got %d", __FUNCTION__, 93 SCM_RIGHTS, cmsg->cmsg_type); 94 fd = (*(int *)CMSG_DATA(cmsg)); 95 return fd; 96 } 97