1  /*
       2   * Copyright (c) 2017 JingPiao Chen <chenjingpiao@gmail.com>
       3   * Copyright (c) 2017-2021 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 <stdio.h>
      11  #include <stdint.h>
      12  #include "test_nlattr.h"
      13  
      14  #define NLMSGERR_ATTR_COOKIE 3
      15  
      16  static void
      17  init_nlmsgerr(struct nlmsghdr *const nlh, const unsigned int msg_len)
      18  {
      19  	SET_STRUCT(struct nlmsghdr, nlh,
      20  		.nlmsg_len = msg_len,
      21  		.nlmsg_type = NLMSG_ERROR,
      22  		.nlmsg_flags = NLM_F_REQUEST | NLM_F_CAPPED
      23  	);
      24  
      25  	struct nlmsgerr *const err = NLMSG_DATA(nlh);
      26  	SET_STRUCT(struct nlmsgerr, err,
      27  		.error = -13,
      28  		.msg = {
      29  			.nlmsg_len = NLMSG_HDRLEN + 4,
      30  			.nlmsg_type = NLMSG_NOOP,
      31  			.nlmsg_flags = NLM_F_REQUEST,
      32  		}
      33  	);
      34  }
      35  
      36  static void
      37  print_nlmsgerr(const unsigned int msg_len)
      38  {
      39  	printf("{nlmsg_len=%u, nlmsg_type=NLMSG_ERROR"
      40  	       ", nlmsg_flags=NLM_F_REQUEST|NLM_F_CAPPED"
      41  	       ", nlmsg_seq=0, nlmsg_pid=0}, [{error=-EACCES"
      42  	       ", msg={nlmsg_len=%u, nlmsg_type=NLMSG_NOOP"
      43  	       ", nlmsg_flags=NLM_F_REQUEST, nlmsg_seq=0, nlmsg_pid=0}}",
      44  	       msg_len, NLMSG_HDRLEN + 4);
      45  }
      46  
      47  int
      48  main(void)
      49  {
      50  	skip_if_unavailable("/proc/self/fd/");
      51  
      52  	static const uint8_t cookie[] = { 0xab, 0xfe };
      53  
      54  	const int fd = create_nl_socket(NETLINK_SOCK_DIAG);
      55  	const unsigned int hdrlen = sizeof(struct nlmsgerr);
      56  	void *const nlh0 = midtail_alloc(NLMSG_SPACE(hdrlen),
      57  			NLA_HDRLEN + sizeof(cookie));
      58  
      59  	TEST_NLATTR(fd, nlh0, hdrlen,
      60  		    init_nlmsgerr, print_nlmsgerr,
      61  		    NLMSGERR_ATTR_COOKIE,
      62  		    sizeof(cookie), cookie, sizeof(cookie),
      63  		    printf("[%u, %u]", cookie[0], cookie[1]);
      64  		    printf("]"));
      65  
      66  	printf("+++ exited with 0 +++\n");
      67  	return 0;
      68  }