monitor_fdpass.c revision 192595
1192595Sdes/* $OpenBSD: monitor_fdpass.c,v 1.18 2008/11/30 11:59:26 dtucker Exp $ */ 298675Sdes/* 398675Sdes * Copyright 2001 Niels Provos <provos@citi.umich.edu> 498675Sdes * All rights reserved. 598675Sdes * 698675Sdes * Redistribution and use in source and binary forms, with or without 798675Sdes * modification, are permitted provided that the following conditions 898675Sdes * are met: 998675Sdes * 1. Redistributions of source code must retain the above copyright 1098675Sdes * notice, this list of conditions and the following disclaimer. 1198675Sdes * 2. Redistributions in binary form must reproduce the above copyright 1298675Sdes * notice, this list of conditions and the following disclaimer in the 1398675Sdes * documentation and/or other materials provided with the distribution. 1498675Sdes * 1598675Sdes * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 1698675Sdes * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 1798675Sdes * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 1898675Sdes * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 1998675Sdes * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 2098675Sdes * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 2198675Sdes * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 2298675Sdes * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 2398675Sdes * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 2498675Sdes * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 2598675Sdes */ 2698675Sdes 2798675Sdes#include "includes.h" 2898675Sdes 29162852Sdes#include <sys/types.h> 30162852Sdes#include <sys/socket.h> 3198675Sdes#include <sys/uio.h> 32164146Sdes#ifdef HAVE_SYS_UN_H 33164146Sdes#include <sys/un.h> 34164146Sdes#endif 3598675Sdes 36162852Sdes#include <errno.h> 37162852Sdes#include <string.h> 38162852Sdes#include <stdarg.h> 39162852Sdes 4098675Sdes#include "log.h" 4198675Sdes#include "monitor_fdpass.h" 4298675Sdes 43181111Sdesint 44137015Sdesmm_send_fd(int sock, int fd) 4598675Sdes{ 4698937Sdes#if defined(HAVE_SENDMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) 4798675Sdes struct msghdr msg; 4898937Sdes#ifndef HAVE_ACCRIGHTS_IN_MSGHDR 49180989Sdes union { 50180989Sdes struct cmsghdr hdr; 51180989Sdes char buf[CMSG_SPACE(sizeof(int))]; 52180989Sdes } cmsgbuf; 5398937Sdes struct cmsghdr *cmsg; 5498937Sdes#endif 55192595Sdes struct iovec vec; 56192595Sdes char ch = '\0'; 57192595Sdes ssize_t n; 5898675Sdes 5998675Sdes memset(&msg, 0, sizeof(msg)); 6098937Sdes#ifdef HAVE_ACCRIGHTS_IN_MSGHDR 6198937Sdes msg.msg_accrights = (caddr_t)&fd; 6298937Sdes msg.msg_accrightslen = sizeof(fd); 6398937Sdes#else 64180989Sdes msg.msg_control = (caddr_t)&cmsgbuf.buf; 65180989Sdes msg.msg_controllen = sizeof(cmsgbuf.buf); 6698675Sdes cmsg = CMSG_FIRSTHDR(&msg); 6798675Sdes cmsg->cmsg_len = CMSG_LEN(sizeof(int)); 6898675Sdes cmsg->cmsg_level = SOL_SOCKET; 6998675Sdes cmsg->cmsg_type = SCM_RIGHTS; 7098675Sdes *(int *)CMSG_DATA(cmsg) = fd; 7198937Sdes#endif 7298675Sdes 7398675Sdes vec.iov_base = &ch; 7498675Sdes vec.iov_len = 1; 7598675Sdes msg.msg_iov = &vec; 7698675Sdes msg.msg_iovlen = 1; 7798675Sdes 78192595Sdes while ((n = sendmsg(sock, &msg, 0)) == -1 && (errno == EAGAIN || 79192595Sdes errno == EINTR)) 80192595Sdes debug3("%s: sendmsg(%d): %s", __func__, fd, strerror(errno)); 81192595Sdes if (n == -1) { 82181111Sdes error("%s: sendmsg(%d): %s", __func__, fd, 8398675Sdes strerror(errno)); 84181111Sdes return -1; 85181111Sdes } 86181111Sdes 87181111Sdes if (n != 1) { 88181111Sdes error("%s: sendmsg: expected sent 1 got %ld", 89106121Sdes __func__, (long)n); 90181111Sdes return -1; 91181111Sdes } 92181111Sdes return 0; 9398937Sdes#else 94181111Sdes error("%s: file descriptor passing not supported", __func__); 95181111Sdes return -1; 9698937Sdes#endif 9798675Sdes} 9898675Sdes 9998675Sdesint 100137015Sdesmm_receive_fd(int sock) 10198675Sdes{ 10298937Sdes#if defined(HAVE_RECVMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) 10398675Sdes struct msghdr msg; 10498937Sdes#ifndef HAVE_ACCRIGHTS_IN_MSGHDR 105180989Sdes union { 106180989Sdes struct cmsghdr hdr; 107180989Sdes char buf[CMSG_SPACE(sizeof(int))]; 108180989Sdes } cmsgbuf; 10998937Sdes struct cmsghdr *cmsg; 11098937Sdes#endif 111192595Sdes struct iovec vec; 112192595Sdes ssize_t n; 113192595Sdes char ch; 114192595Sdes int fd; 11598675Sdes 11698675Sdes memset(&msg, 0, sizeof(msg)); 11798675Sdes vec.iov_base = &ch; 11898675Sdes vec.iov_len = 1; 11998675Sdes msg.msg_iov = &vec; 12098675Sdes msg.msg_iovlen = 1; 12198937Sdes#ifdef HAVE_ACCRIGHTS_IN_MSGHDR 12298937Sdes msg.msg_accrights = (caddr_t)&fd; 12398937Sdes msg.msg_accrightslen = sizeof(fd); 12498937Sdes#else 125180989Sdes msg.msg_control = &cmsgbuf.buf; 126180989Sdes msg.msg_controllen = sizeof(cmsgbuf.buf); 12798937Sdes#endif 12898675Sdes 129192595Sdes while ((n = recvmsg(sock, &msg, 0)) == -1 && (errno == EAGAIN || 130192595Sdes errno == EINTR)) 131192595Sdes debug3("%s: recvmsg: %s", __func__, strerror(errno)); 132192595Sdes if (n == -1) { 133181111Sdes error("%s: recvmsg: %s", __func__, strerror(errno)); 134181111Sdes return -1; 135181111Sdes } 136192595Sdes 137181111Sdes if (n != 1) { 138181111Sdes error("%s: recvmsg: expected received 1 got %ld", 139106121Sdes __func__, (long)n); 140181111Sdes return -1; 141181111Sdes } 14298675Sdes 14398937Sdes#ifdef HAVE_ACCRIGHTS_IN_MSGHDR 144181111Sdes if (msg.msg_accrightslen != sizeof(fd)) { 145181111Sdes error("%s: no fd", __func__); 146181111Sdes return -1; 147181111Sdes } 14898937Sdes#else 14998675Sdes cmsg = CMSG_FIRSTHDR(&msg); 150181111Sdes if (cmsg == NULL) { 151181111Sdes error("%s: no message header", __func__); 152181111Sdes return -1; 153181111Sdes } 154192595Sdes 155124208Sdes#ifndef BROKEN_CMSG_TYPE 156181111Sdes if (cmsg->cmsg_type != SCM_RIGHTS) { 157181111Sdes error("%s: expected type %d got %d", __func__, 15898675Sdes SCM_RIGHTS, cmsg->cmsg_type); 159181111Sdes return -1; 160181111Sdes } 161124208Sdes#endif 16298675Sdes fd = (*(int *)CMSG_DATA(cmsg)); 16398937Sdes#endif 16498675Sdes return fd; 16598937Sdes#else 166181111Sdes error("%s: file descriptor passing not supported", __func__); 167181111Sdes return -1; 16898937Sdes#endif 16998675Sdes} 170