1294332Sdes/* $OpenBSD: monitor_fdpass.c,v 1.20 2015/02/25 23:05:47 djm 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 40294328Sdes#ifdef HAVE_POLL_H 41294328Sdes# include <poll.h> 42294328Sdes#else 43294328Sdes# ifdef HAVE_SYS_POLL_H 44294328Sdes# include <sys/poll.h> 45294328Sdes# endif 46294328Sdes#endif 47294328Sdes 4898675Sdes#include "log.h" 4998675Sdes#include "monitor_fdpass.h" 5098675Sdes 51181111Sdesint 52137015Sdesmm_send_fd(int sock, int fd) 5398675Sdes{ 5498937Sdes#if defined(HAVE_SENDMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) 5598675Sdes struct msghdr msg; 5698937Sdes#ifndef HAVE_ACCRIGHTS_IN_MSGHDR 57180989Sdes union { 58180989Sdes struct cmsghdr hdr; 59180989Sdes char buf[CMSG_SPACE(sizeof(int))]; 60180989Sdes } cmsgbuf; 6198937Sdes struct cmsghdr *cmsg; 6298937Sdes#endif 63192595Sdes struct iovec vec; 64192595Sdes char ch = '\0'; 65192595Sdes ssize_t n; 66204917Sdes struct pollfd pfd; 6798675Sdes 6898675Sdes memset(&msg, 0, sizeof(msg)); 6998937Sdes#ifdef HAVE_ACCRIGHTS_IN_MSGHDR 7098937Sdes msg.msg_accrights = (caddr_t)&fd; 7198937Sdes msg.msg_accrightslen = sizeof(fd); 7298937Sdes#else 73294332Sdes memset(&cmsgbuf, 0, sizeof(cmsgbuf)); 74180989Sdes msg.msg_control = (caddr_t)&cmsgbuf.buf; 75180989Sdes msg.msg_controllen = sizeof(cmsgbuf.buf); 7698675Sdes cmsg = CMSG_FIRSTHDR(&msg); 7798675Sdes cmsg->cmsg_len = CMSG_LEN(sizeof(int)); 7898675Sdes cmsg->cmsg_level = SOL_SOCKET; 7998675Sdes cmsg->cmsg_type = SCM_RIGHTS; 8098675Sdes *(int *)CMSG_DATA(cmsg) = fd; 8198937Sdes#endif 8298675Sdes 8398675Sdes vec.iov_base = &ch; 8498675Sdes vec.iov_len = 1; 8598675Sdes msg.msg_iov = &vec; 8698675Sdes msg.msg_iovlen = 1; 8798675Sdes 88204917Sdes pfd.fd = sock; 89204917Sdes pfd.events = POLLOUT; 90204917Sdes while ((n = sendmsg(sock, &msg, 0)) == -1 && 91204917Sdes (errno == EAGAIN || errno == EINTR)) { 92192595Sdes debug3("%s: sendmsg(%d): %s", __func__, fd, strerror(errno)); 93204917Sdes (void)poll(&pfd, 1, -1); 94204917Sdes } 95192595Sdes if (n == -1) { 96181111Sdes error("%s: sendmsg(%d): %s", __func__, fd, 9798675Sdes strerror(errno)); 98181111Sdes return -1; 99181111Sdes } 100181111Sdes 101181111Sdes if (n != 1) { 102181111Sdes error("%s: sendmsg: expected sent 1 got %ld", 103106121Sdes __func__, (long)n); 104181111Sdes return -1; 105181111Sdes } 106181111Sdes return 0; 10798937Sdes#else 108181111Sdes error("%s: file descriptor passing not supported", __func__); 109181111Sdes return -1; 11098937Sdes#endif 11198675Sdes} 11298675Sdes 11398675Sdesint 114137015Sdesmm_receive_fd(int sock) 11598675Sdes{ 11698937Sdes#if defined(HAVE_RECVMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) 11798675Sdes struct msghdr msg; 11898937Sdes#ifndef HAVE_ACCRIGHTS_IN_MSGHDR 119180989Sdes union { 120180989Sdes struct cmsghdr hdr; 121180989Sdes char buf[CMSG_SPACE(sizeof(int))]; 122180989Sdes } cmsgbuf; 12398937Sdes struct cmsghdr *cmsg; 12498937Sdes#endif 125192595Sdes struct iovec vec; 126192595Sdes ssize_t n; 127192595Sdes char ch; 128192595Sdes int fd; 129204917Sdes struct pollfd pfd; 13098675Sdes 13198675Sdes memset(&msg, 0, sizeof(msg)); 13298675Sdes vec.iov_base = &ch; 13398675Sdes vec.iov_len = 1; 13498675Sdes msg.msg_iov = &vec; 13598675Sdes msg.msg_iovlen = 1; 13698937Sdes#ifdef HAVE_ACCRIGHTS_IN_MSGHDR 13798937Sdes msg.msg_accrights = (caddr_t)&fd; 13898937Sdes msg.msg_accrightslen = sizeof(fd); 13998937Sdes#else 140294332Sdes memset(&cmsgbuf, 0, sizeof(cmsgbuf)); 141180989Sdes msg.msg_control = &cmsgbuf.buf; 142180989Sdes msg.msg_controllen = sizeof(cmsgbuf.buf); 14398937Sdes#endif 14498675Sdes 145204917Sdes pfd.fd = sock; 146204917Sdes pfd.events = POLLIN; 147204917Sdes while ((n = recvmsg(sock, &msg, 0)) == -1 && 148204917Sdes (errno == EAGAIN || errno == EINTR)) { 149192595Sdes debug3("%s: recvmsg: %s", __func__, strerror(errno)); 150204917Sdes (void)poll(&pfd, 1, -1); 151204917Sdes } 152192595Sdes if (n == -1) { 153181111Sdes error("%s: recvmsg: %s", __func__, strerror(errno)); 154181111Sdes return -1; 155181111Sdes } 156192595Sdes 157181111Sdes if (n != 1) { 158181111Sdes error("%s: recvmsg: expected received 1 got %ld", 159106121Sdes __func__, (long)n); 160181111Sdes return -1; 161181111Sdes } 16298675Sdes 16398937Sdes#ifdef HAVE_ACCRIGHTS_IN_MSGHDR 164181111Sdes if (msg.msg_accrightslen != sizeof(fd)) { 165181111Sdes error("%s: no fd", __func__); 166181111Sdes return -1; 167181111Sdes } 16898937Sdes#else 16998675Sdes cmsg = CMSG_FIRSTHDR(&msg); 170181111Sdes if (cmsg == NULL) { 171181111Sdes error("%s: no message header", __func__); 172181111Sdes return -1; 173181111Sdes } 174192595Sdes 175124208Sdes#ifndef BROKEN_CMSG_TYPE 176181111Sdes if (cmsg->cmsg_type != SCM_RIGHTS) { 177181111Sdes error("%s: expected type %d got %d", __func__, 17898675Sdes SCM_RIGHTS, cmsg->cmsg_type); 179181111Sdes return -1; 180181111Sdes } 181124208Sdes#endif 18298675Sdes fd = (*(int *)CMSG_DATA(cmsg)); 18398937Sdes#endif 18498675Sdes return fd; 18598937Sdes#else 186181111Sdes error("%s: file descriptor passing not supported", __func__); 187181111Sdes return -1; 18898937Sdes#endif 18998675Sdes} 190