1 /* 2 * Copyright (c) 2014-2015 Dmitry V. Levin <ldv (at) altlinux.org> 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 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <assert.h> 29 #include <string.h> 30 #include <stdlib.h> 31 #include <unistd.h> 32 #include <errno.h> 33 #include <fcntl.h> 34 #include <sys/socket.h> 35 #include <sys/wait.h> 36 37 int main(int ac, const char **av) 38 { 39 int i; 40 int data = 0; 41 struct iovec iov = { 42 .iov_base = &data, 43 .iov_len = sizeof(iov) 44 }; 45 46 while ((i = open("/dev/null", O_RDWR)) < 3) 47 assert(i >= 0); 48 (void) close(3); 49 50 int sv[2]; 51 assert(socketpair(AF_UNIX, SOCK_STREAM, 0, sv) == 0); 52 int one = 1; 53 assert(setsockopt(sv[0], SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)) == 0); 54 55 pid_t pid = fork(); 56 assert(pid >= 0); 57 58 if (pid) { 59 assert(close(sv[0]) == 0); 60 assert(dup2(sv[1], 1) == 1); 61 assert(close(sv[1]) == 0); 62 63 int fds[ac]; 64 assert((fds[0] = open("/dev/null", O_RDWR)) == 3); 65 for (i = 1; i < ac; ++i) 66 assert((fds[i] = open(av[i], O_RDONLY)) == i + 3); 67 68 union { 69 struct cmsghdr cmsg; 70 char buf[CMSG_LEN(sizeof(fds))]; 71 } control; 72 73 control.cmsg.cmsg_level = SOL_SOCKET; 74 control.cmsg.cmsg_type = SCM_RIGHTS; 75 control.cmsg.cmsg_len = CMSG_LEN(sizeof(fds)); 76 memcpy(CMSG_DATA(&control.cmsg), fds, sizeof(fds)); 77 78 struct msghdr mh = { 79 .msg_iov = &iov, 80 .msg_iovlen = 1, 81 .msg_control = &control, 82 .msg_controllen = sizeof(control) 83 }; 84 85 assert(sendmsg(1, &mh, 0) == sizeof(iov)); 86 assert(close(1) == 0); 87 88 int status; 89 assert(waitpid(pid, &status, 0) == pid); 90 assert(status == 0); 91 } else { 92 assert(close(sv[1]) == 0); 93 assert(dup2(sv[0], 0) == 0); 94 assert(close(sv[0]) == 0); 95 96 struct cmsghdr control[4 + ac * sizeof(int) / sizeof(struct cmsghdr)]; 97 98 struct msghdr mh = { 99 .msg_iov = &iov, 100 .msg_iovlen = 1, 101 .msg_control = control, 102 .msg_controllen = sizeof(control) 103 }; 104 105 assert(recvmsg(0, &mh, 0) == sizeof(iov)); 106 assert(close(0) == 0); 107 } 108 109 return 0; 110 } 111
