Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1 | /* $OpenBSD: monitor_fdpass.c,v 1.20 2015/02/25 23:05:47 djm Exp $ */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 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> |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 37 | #include <string.h> |
| 38 | #include <stdarg.h> |
| 39 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 40 | #ifdef HAVE_POLL_H |
| 41 | # include <poll.h> |
| 42 | #else |
| 43 | # ifdef HAVE_SYS_POLL_H |
| 44 | # include <sys/poll.h> |
| 45 | # endif |
| 46 | #endif |
| 47 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 48 | #include "log.h" |
| 49 | #include "monitor_fdpass.h" |
| 50 | |
| 51 | int |
| 52 | mm_send_fd(int sock, int fd) |
| 53 | { |
| 54 | #if defined(HAVE_SENDMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) |
| 55 | struct msghdr msg; |
| 56 | #ifndef HAVE_ACCRIGHTS_IN_MSGHDR |
| 57 | union { |
| 58 | struct cmsghdr hdr; |
| 59 | char buf[CMSG_SPACE(sizeof(int))]; |
| 60 | } cmsgbuf; |
| 61 | struct cmsghdr *cmsg; |
| 62 | #endif |
| 63 | struct iovec vec; |
| 64 | char ch = '\0'; |
| 65 | ssize_t n; |
| 66 | struct pollfd pfd; |
| 67 | |
| 68 | memset(&msg, 0, sizeof(msg)); |
| 69 | #ifdef HAVE_ACCRIGHTS_IN_MSGHDR |
| 70 | msg.msg_accrights = (caddr_t)&fd; |
| 71 | msg.msg_accrightslen = sizeof(fd); |
| 72 | #else |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 73 | memset(&cmsgbuf, 0, sizeof(cmsgbuf)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 74 | msg.msg_control = (caddr_t)&cmsgbuf.buf; |
| 75 | msg.msg_controllen = sizeof(cmsgbuf.buf); |
| 76 | cmsg = CMSG_FIRSTHDR(&msg); |
| 77 | cmsg->cmsg_len = CMSG_LEN(sizeof(int)); |
| 78 | cmsg->cmsg_level = SOL_SOCKET; |
| 79 | cmsg->cmsg_type = SCM_RIGHTS; |
| 80 | *(int *)CMSG_DATA(cmsg) = fd; |
| 81 | #endif |
| 82 | |
| 83 | vec.iov_base = &ch; |
| 84 | vec.iov_len = 1; |
| 85 | msg.msg_iov = &vec; |
| 86 | msg.msg_iovlen = 1; |
| 87 | |
| 88 | pfd.fd = sock; |
| 89 | pfd.events = POLLOUT; |
| 90 | while ((n = sendmsg(sock, &msg, 0)) == -1 && |
| 91 | (errno == EAGAIN || errno == EINTR)) { |
| 92 | debug3("%s: sendmsg(%d): %s", __func__, fd, strerror(errno)); |
| 93 | (void)poll(&pfd, 1, -1); |
| 94 | } |
| 95 | if (n == -1) { |
| 96 | error("%s: sendmsg(%d): %s", __func__, fd, |
| 97 | strerror(errno)); |
| 98 | return -1; |
| 99 | } |
| 100 | |
| 101 | if (n != 1) { |
| 102 | error("%s: sendmsg: expected sent 1 got %ld", |
| 103 | __func__, (long)n); |
| 104 | return -1; |
| 105 | } |
| 106 | return 0; |
| 107 | #else |
| 108 | error("%s: file descriptor passing not supported", __func__); |
| 109 | return -1; |
| 110 | #endif |
| 111 | } |
| 112 | |
| 113 | int |
| 114 | mm_receive_fd(int sock) |
| 115 | { |
| 116 | #if defined(HAVE_RECVMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR)) |
| 117 | struct msghdr msg; |
| 118 | #ifndef HAVE_ACCRIGHTS_IN_MSGHDR |
| 119 | union { |
| 120 | struct cmsghdr hdr; |
| 121 | char buf[CMSG_SPACE(sizeof(int))]; |
| 122 | } cmsgbuf; |
| 123 | struct cmsghdr *cmsg; |
| 124 | #endif |
| 125 | struct iovec vec; |
| 126 | ssize_t n; |
| 127 | char ch; |
| 128 | int fd; |
| 129 | struct pollfd pfd; |
| 130 | |
| 131 | memset(&msg, 0, sizeof(msg)); |
| 132 | vec.iov_base = &ch; |
| 133 | vec.iov_len = 1; |
| 134 | msg.msg_iov = &vec; |
| 135 | msg.msg_iovlen = 1; |
| 136 | #ifdef HAVE_ACCRIGHTS_IN_MSGHDR |
| 137 | msg.msg_accrights = (caddr_t)&fd; |
| 138 | msg.msg_accrightslen = sizeof(fd); |
| 139 | #else |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 140 | memset(&cmsgbuf, 0, sizeof(cmsgbuf)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 141 | msg.msg_control = &cmsgbuf.buf; |
| 142 | msg.msg_controllen = sizeof(cmsgbuf.buf); |
| 143 | #endif |
| 144 | |
| 145 | pfd.fd = sock; |
| 146 | pfd.events = POLLIN; |
| 147 | while ((n = recvmsg(sock, &msg, 0)) == -1 && |
| 148 | (errno == EAGAIN || errno == EINTR)) { |
| 149 | debug3("%s: recvmsg: %s", __func__, strerror(errno)); |
| 150 | (void)poll(&pfd, 1, -1); |
| 151 | } |
| 152 | if (n == -1) { |
| 153 | error("%s: recvmsg: %s", __func__, strerror(errno)); |
| 154 | return -1; |
| 155 | } |
| 156 | |
| 157 | if (n != 1) { |
| 158 | error("%s: recvmsg: expected received 1 got %ld", |
| 159 | __func__, (long)n); |
| 160 | return -1; |
| 161 | } |
| 162 | |
| 163 | #ifdef HAVE_ACCRIGHTS_IN_MSGHDR |
| 164 | if (msg.msg_accrightslen != sizeof(fd)) { |
| 165 | error("%s: no fd", __func__); |
| 166 | return -1; |
| 167 | } |
| 168 | #else |
| 169 | cmsg = CMSG_FIRSTHDR(&msg); |
| 170 | if (cmsg == NULL) { |
| 171 | error("%s: no message header", __func__); |
| 172 | return -1; |
| 173 | } |
| 174 | |
| 175 | #ifndef BROKEN_CMSG_TYPE |
| 176 | if (cmsg->cmsg_type != SCM_RIGHTS) { |
| 177 | error("%s: expected type %d got %d", __func__, |
| 178 | SCM_RIGHTS, cmsg->cmsg_type); |
| 179 | return -1; |
| 180 | } |
| 181 | #endif |
| 182 | fd = (*(int *)CMSG_DATA(cmsg)); |
| 183 | #endif |
| 184 | return fd; |
| 185 | #else |
| 186 | error("%s: file descriptor passing not supported", __func__); |
| 187 | return -1; |
| 188 | #endif |
| 189 | } |