Annotation of src/usr.bin/ssh/monitor_fdpass.c, Revision 1.21
1.21 ! jca 1: /* $OpenBSD: monitor_fdpass.c,v 1.20 2015/02/25 23:05:47 djm Exp $ */
1.1 provos 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:
1.9 stevesk 27: #include <sys/types.h>
28: #include <sys/socket.h>
1.1 provos 29: #include <sys/uio.h>
1.10 stevesk 30:
31: #include <errno.h>
1.19 djm 32: #include <poll.h>
1.11 stevesk 33: #include <string.h>
1.12 deraadt 34: #include <stdarg.h>
1.1 provos 35:
36: #include "log.h"
37: #include "monitor_fdpass.h"
38:
1.13 djm 39: int
1.5 avsm 40: mm_send_fd(int sock, int fd)
1.1 provos 41: {
42: struct msghdr msg;
1.14 deraadt 43: union {
44: struct cmsghdr hdr;
1.15 deraadt 45: char buf[CMSG_SPACE(sizeof(int))];
46: } cmsgbuf;
1.1 provos 47: struct cmsghdr *cmsg;
48: struct iovec vec;
1.2 stevesk 49: char ch = '\0';
1.4 deraadt 50: ssize_t n;
1.19 djm 51: struct pollfd pfd;
1.1 provos 52:
53: memset(&msg, 0, sizeof(msg));
1.20 djm 54: memset(&cmsgbuf, 0, sizeof(cmsgbuf));
1.15 deraadt 55: msg.msg_control = (caddr_t)&cmsgbuf.buf;
1.17 deraadt 56: msg.msg_controllen = sizeof(cmsgbuf.buf);
1.1 provos 57: cmsg = CMSG_FIRSTHDR(&msg);
58: cmsg->cmsg_len = CMSG_LEN(sizeof(int));
59: cmsg->cmsg_level = SOL_SOCKET;
60: cmsg->cmsg_type = SCM_RIGHTS;
61: *(int *)CMSG_DATA(cmsg) = fd;
62:
63: vec.iov_base = &ch;
64: vec.iov_len = 1;
65: msg.msg_iov = &vec;
66: msg.msg_iovlen = 1;
67:
1.19 djm 68: pfd.fd = sock;
69: pfd.events = POLLOUT;
70: while ((n = sendmsg(sock, &msg, 0)) == -1 &&
71: (errno == EAGAIN || errno == EINTR)) {
1.18 dtucker 72: debug3("%s: sendmsg(%d): %s", __func__, fd, strerror(errno));
1.19 djm 73: (void)poll(&pfd, 1, -1);
74: }
1.18 dtucker 75: if (n == -1) {
1.13 djm 76: error("%s: sendmsg(%d): %s", __func__, fd,
1.2 stevesk 77: strerror(errno));
1.13 djm 78: return -1;
79: }
80:
81: if (n != 1) {
1.21 ! jca 82: error("%s: sendmsg: expected sent 1 got %zd", __func__, n);
1.13 djm 83: return -1;
84: }
85: return 0;
1.1 provos 86: }
87:
88: int
1.5 avsm 89: mm_receive_fd(int sock)
1.1 provos 90: {
91: struct msghdr msg;
1.14 deraadt 92: union {
93: struct cmsghdr hdr;
1.15 deraadt 94: char buf[CMSG_SPACE(sizeof(int))];
95: } cmsgbuf;
1.1 provos 96: struct cmsghdr *cmsg;
97: struct iovec vec;
1.4 deraadt 98: ssize_t n;
1.1 provos 99: char ch;
1.4 deraadt 100: int fd;
1.19 djm 101: struct pollfd pfd;
1.1 provos 102:
103: memset(&msg, 0, sizeof(msg));
1.20 djm 104: memset(&cmsgbuf, 0, sizeof(cmsgbuf));
1.1 provos 105: vec.iov_base = &ch;
106: vec.iov_len = 1;
107: msg.msg_iov = &vec;
108: msg.msg_iovlen = 1;
1.15 deraadt 109: msg.msg_control = &cmsgbuf.buf;
1.17 deraadt 110: msg.msg_controllen = sizeof(cmsgbuf.buf);
1.1 provos 111:
1.19 djm 112: pfd.fd = sock;
113: pfd.events = POLLIN;
114: while ((n = recvmsg(sock, &msg, 0)) == -1 &&
115: (errno == EAGAIN || errno == EINTR)) {
1.18 dtucker 116: debug3("%s: recvmsg: %s", __func__, strerror(errno));
1.19 djm 117: (void)poll(&pfd, 1, -1);
118: }
1.18 dtucker 119: if (n == -1) {
1.13 djm 120: error("%s: recvmsg: %s", __func__, strerror(errno));
121: return -1;
122: }
123:
124: if (n != 1) {
1.21 ! jca 125: error("%s: recvmsg: expected received 1 got %zd", __func__, n);
1.13 djm 126: return -1;
127: }
1.1 provos 128:
129: cmsg = CMSG_FIRSTHDR(&msg);
1.13 djm 130: if (cmsg == NULL) {
131: error("%s: no message header", __func__);
132: return -1;
133: }
134:
135: if (cmsg->cmsg_type != SCM_RIGHTS) {
136: error("%s: expected type %d got %d", __func__,
1.1 provos 137: SCM_RIGHTS, cmsg->cmsg_type);
1.13 djm 138: return -1;
139: }
1.2 stevesk 140: fd = (*(int *)CMSG_DATA(cmsg));
141: return fd;
1.1 provos 142: }