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/*
* Copyright (c) 2015-2016 Dmitry V. Levin <ldv@strace.io>
* Copyright (c) 2015-2021 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include <assert.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
static void
print_pktinfo(const struct cmsghdr *c)
{
printf("IP_PKTINFO, cmsg_data={ipi_ifindex=%s"
", ipi_spec_dst=inet_addr(\"%s\")"
", ipi_addr=inet_addr(\"%s\")}",
IFINDEX_LO_STR, "127.0.0.1", "127.0.0.1");
}
static void
print_ttl(const struct cmsghdr *c)
{
const unsigned int *ttl = (const unsigned int *) CMSG_DATA(c);
printf("IP_TTL, cmsg_data=[%u]", *ttl);
}
static void
print_tos(const struct cmsghdr *c)
{
const uint8_t *tos = (const uint8_t *) CMSG_DATA(c);
printf("IP_TOS, cmsg_data=[%#x]", *tos);
}
static void
print_opts(const char *name, const struct cmsghdr *c)
{
const unsigned char *opts = (const unsigned char *) CMSG_DATA(c);
const size_t len = c->cmsg_len - CMSG_ALIGN(sizeof(*c));
printf("%s", name);
if (len) {
printf(", cmsg_data=[");
for (size_t i = 0; i < len; ++i)
printf("%s%#x", i ? ", " : "", opts[i]);
printf("]");
}
}
#ifdef IP_ORIGDSTADDR
static void
print_origdstaddr(const struct cmsghdr *c)
{
const struct sockaddr_in *sin =
(const struct sockaddr_in *) CMSG_DATA(c);
printf("IP_ORIGDSTADDR, cmsg_data={sa_family=AF_INET, sin_port=htons(%u)"
", sin_addr=inet_addr(\"127.0.0.1\")}", ntohs(sin->sin_port));
}
#endif
int
main(void)
{
int i;
while ((i = open("/dev/null", O_RDWR)) < 3)
assert(i >= 0);
assert(!close(0));
assert(!close(3));
if (socket(AF_INET, SOCK_DGRAM, 0))
perror_msg_and_skip("socket");
struct sockaddr_in addr = {
.sin_family = AF_INET,
.sin_addr.s_addr = htonl(INADDR_LOOPBACK)
};
socklen_t len = sizeof(addr);
if (bind(0, (struct sockaddr *) &addr, len))
perror_msg_and_skip("bind");
assert(!getsockname(0, (struct sockaddr *) &addr, &len));
assert(socket(AF_INET, SOCK_DGRAM, 0) == 3);
assert(!connect(3, (struct sockaddr *) &addr, len));
const int opt_1 = htonl(0x01000000);
#define SETSOCKOPT(fd, name) assert(!setsockopt(fd, IPPROTO_IP, (name), &opt_1, sizeof(opt_1)))
SETSOCKOPT(3, IP_OPTIONS);
SETSOCKOPT(0, IP_PKTINFO);
SETSOCKOPT(0, IP_RECVTTL);
SETSOCKOPT(0, IP_RECVTOS);
SETSOCKOPT(0, IP_RECVOPTS);
SETSOCKOPT(0, IP_RETOPTS);
#ifdef IP_RECVORIGDSTADDR
SETSOCKOPT(0, IP_RECVORIGDSTADDR);
#endif
static const char data[] = "data";
const size_t size = sizeof(data) - 1;
assert(send(3, data, size, 0) == (int) size);
assert(!close(3));
char buf[size];
struct iovec iov = {
.iov_base = buf,
.iov_len = sizeof(buf)
};
struct cmsghdr control[16];
struct msghdr mh = {
.msg_name = &addr,
.msg_namelen = len,
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_control = control,
.msg_controllen = sizeof(control)
};
assert(recvmsg(0, &mh, 0) == (int) size);
assert(!close(0));
printf("recvmsg(0, {msg_name={sa_family=AF_INET, sin_port=htons(%u)"
", sin_addr=inet_addr(\"127.0.0.1\")}, msg_namelen=%u"
", msg_iov=[{iov_base=\"%s\", iov_len=%u}], msg_iovlen=1"
", msg_control=[",
ntohs(addr.sin_port), (unsigned) mh.msg_namelen,
data, (unsigned) size);
for (struct cmsghdr *c = CMSG_FIRSTHDR(&mh);
c; c = CMSG_NXTHDR(&mh, c)) {
if (IPPROTO_IP != c->cmsg_level)
continue;
if (c != control)
printf(", ");
printf("{cmsg_len=%lu, cmsg_level=SOL_IP, cmsg_type=",
(unsigned long) c->cmsg_len);
switch (c->cmsg_type) {
case IP_PKTINFO:
print_pktinfo(c);
break;
case IP_TTL:
print_ttl(c);
break;
case IP_TOS:
print_tos(c);
break;
case IP_RECVOPTS:
print_opts("IP_RECVOPTS", c);
break;
case IP_RETOPTS:
print_opts("IP_RETOPTS", c);
break;
#ifdef IP_ORIGDSTADDR
case IP_ORIGDSTADDR:
print_origdstaddr(c);
break;
#endif
default:
printf("%d", c->cmsg_type);
break;
}
printf("}");
}
printf("], msg_controllen=%lu, msg_flags=0}, 0) = %u\n",
(unsigned long) mh.msg_controllen, (unsigned) size);
puts("+++ exited with 0 +++");
return 0;
}
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