1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
/*
* Check decoding of SCM_PIDFD control messages.
*
* Copyright (c) 2023-2024 Dmitry V. Levin <ldv@strace.io>
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#define XLAT_MACROS_ONLY
# include "xlat/sock_options.h"
# include "xlat/scmvals.h"
#undef XLAT_MACROS_ONLY
static void
print_pidfd(const struct cmsghdr *c)
{
const void *cmsg_header = c;
const void *cmsg_data = CMSG_DATA(c);
int pidfd;
const unsigned int expected_len = sizeof(pidfd);
const unsigned int data_len = c->cmsg_len - (cmsg_data - cmsg_header);
if (expected_len != data_len)
perror_msg_and_fail("sizeof(pidfd) = %u, data_len = %u\n",
expected_len, data_len);
memcpy(&pidfd, cmsg_data, sizeof(pidfd));
printf("%d<%s>", pidfd, get_fd_path(pidfd));
}
int
main(void)
{
skip_if_unavailable("/proc/self/fd/");
int sv[2];
if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv))
perror_msg_and_skip("socketpair AF_UNIX SOCK_STREAM");
int one = 1;
if (setsockopt(sv[0], SOL_SOCKET, SO_PASSPIDFD, &one, sizeof(one)))
perror_msg_and_skip("setsockopt SO_PASSPIDFD");
char sym = 'A';
if (send(sv[1], &sym, 1, 0) != 1)
perror_msg_and_fail("send");
if (close(sv[1]))
perror_msg_and_fail("close send");
int pidfd;
unsigned int cmsg_size = CMSG_SPACE(sizeof(pidfd));
struct cmsghdr *cmsg = tail_alloc(cmsg_size);
memset(cmsg, 0, cmsg_size);
struct iovec iov = {
.iov_base = &sym,
.iov_len = sizeof(sym)
};
struct msghdr mh = {
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_control = cmsg,
.msg_controllen = cmsg_size
};
if (recvmsg(sv[0], &mh, 0) != 1)
perror_msg_and_fail("recvmsg");
printf("recvmsg(%d<socket:[%lu]>, {msg_name=NULL, msg_namelen=0"
", msg_iov=[{iov_base=\"A\", iov_len=1}], msg_iovlen=1",
sv[0], inode_of_sockfd(sv[0]));
bool found = false;
if (mh.msg_controllen) {
printf(", msg_control=[");
for (struct cmsghdr *c = CMSG_FIRSTHDR(&mh); c;
c = CMSG_NXTHDR(&mh, c)) {
printf("%s{cmsg_len=%lu, cmsg_level=",
(c == cmsg ? "" : ", "),
(unsigned long) c->cmsg_len);
if (c->cmsg_level == SOL_SOCKET) {
printf("SOL_SOCKET");
} else {
printf("%d /* expected SOL_SOCKET == %d */",
c->cmsg_level, (int) SOL_SOCKET);
}
printf(", cmsg_type=");
if (c->cmsg_type == SCM_PIDFD) {
printf("SCM_PIDFD, cmsg_data=");
print_pidfd(c);
found = true;
} else {
printf("%d /* expected SCM_PIDFD == %d */",
c->cmsg_type, (int) SCM_PIDFD);
}
printf("}");
}
printf("]");
}
printf(", msg_controllen=%lu, msg_flags=0}, 0) = 1\n",
(unsigned long) mh.msg_controllen);
if (!found)
error_msg_and_fail("SCM_PIDFD not found");
puts("+++ exited with 0 +++");
return 0;
}
|
