1  /*
       2   * Copyright (c) 2014-2016 Dmitry V. Levin <ldv@strace.io>
       3   * Copyright (c) 2014-2021 The strace developers.
       4   * All rights reserved.
       5   *
       6   * SPDX-License-Identifier: GPL-2.0-or-later
       7   */
       8  
       9  #include "tests.h"
      10  #include <assert.h>
      11  #include <fcntl.h>
      12  #include <stdlib.h>
      13  #include <string.h>
      14  #include <unistd.h>
      15  #include <sys/socket.h>
      16  
      17  int main(int ac, const char **av)
      18  {
      19  	assert(ac > 0);
      20  	int fds[ac];
      21  
      22  	static const char sample[] =
      23  		"\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff";
      24  	const unsigned int data_size = sizeof(sample) - 1;
      25  	void *data = tail_alloc(data_size);
      26  	memcpy(data, sample, data_size);
      27  
      28  	TAIL_ALLOC_OBJECT_CONST_PTR(struct iovec, iov);
      29  	iov->iov_base = data;
      30  	iov->iov_len = data_size;
      31  
      32  	TAIL_ALLOC_OBJECT_CONST_PTR(struct msghdr, mh);
      33  	memset(mh, 0, sizeof(*mh));
      34  	mh->msg_iov = iov;
      35  	mh->msg_iovlen = 1;
      36  
      37  	int i;
      38  	while ((i = open("/dev/null", O_RDWR)) <= ac + 2)
      39  		assert(i >= 0);
      40  	while (i > 2)
      41  		assert(close(i--) == 0);
      42  	assert(close(0) == 0);
      43  
      44  	int sv[2];
      45  	if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv))
      46  		perror_msg_and_skip("socketpair");
      47  	int one = 1;
      48  	if (setsockopt(sv[0], SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)))
      49  		perror_msg_and_skip("setsockopt");
      50  
      51  	assert((fds[0] = open("/dev/null", O_RDWR)) == 4);
      52  	for (i = 1; i < ac; ++i)
      53  		assert((fds[i] = open(av[i], O_RDONLY)) == i + 4);
      54  
      55  	unsigned int cmsg_size = CMSG_SPACE(sizeof(fds));
      56  	struct cmsghdr *cmsg = tail_alloc(cmsg_size);
      57  	memset(cmsg, 0, cmsg_size);
      58  	cmsg->cmsg_level = SOL_SOCKET;
      59  	cmsg->cmsg_type = SCM_RIGHTS;
      60  	cmsg->cmsg_len = CMSG_LEN(sizeof(fds));
      61  	memcpy(CMSG_DATA(cmsg), fds, sizeof(fds));
      62  
      63  	mh->msg_control = cmsg;
      64  	mh->msg_controllen = cmsg_size;
      65  
      66  	assert(sendmsg(sv[1], mh, 0) == (int) data_size);
      67  
      68  	assert(close(sv[1]) == 0);
      69  	assert(open("/dev/null", O_RDWR) == sv[1]);
      70  
      71  	for (i = 0; i < ac; ++i) {
      72  		assert(close(fds[i]) == 0);
      73  		fds[i] = 0;
      74  	}
      75  
      76  	cmsg_size += CMSG_SPACE(sizeof(struct ucred));
      77  	cmsg = tail_alloc(cmsg_size);
      78  	memset(cmsg, 0, cmsg_size);
      79  	mh->msg_control = cmsg;
      80  	mh->msg_controllen = cmsg_size;
      81  
      82  	assert(recvmsg(0, mh, 0) == (int) data_size);
      83  	assert(close(0) == 0);
      84  
      85  	return 0;
      86  }