selftests: mptcp: add mptcp getsockopt test cases

Add a test program that retrieves the three info types:
1. mptcp meta information
2. tcp info for subflow
3. subflow endpoint addresses

For all three rudimentary checks are added.

1. Meta information checks that the logical mptcp
   sequence numbers advance as expected, based on the bytes read
   (init seq + bytes_received/sent) and the connection state
   (after close, we should exect 1 extra byte due to FIN).

2. TCP info checks the number of bytes sent/received vs.
   sums of read/write syscall return values.

3. Subflow endpoint addresses are checked vs. getsockname/getpeername
   result.

Tests for forward compatibility (0-initialisation of output-only
fields in mptcp_subflow_data structure) are added as well.

Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Florian Westphal 2021-09-17 16:33:22 -07:00 committed by David S. Miller
parent c11c5906bc
commit ce9979129a
4 changed files with 714 additions and 3 deletions

View file

@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0-only
mptcp_connect
mptcp_sockopt
pm_nl_ctl
*.pcap

View file

@ -8,7 +8,7 @@ CFLAGS = -Wall -Wl,--no-as-needed -O2 -g -I$(top_srcdir)/usr/include
TEST_PROGS := mptcp_connect.sh pm_netlink.sh mptcp_join.sh diag.sh \
simult_flows.sh mptcp_sockopt.sh
TEST_GEN_FILES = mptcp_connect pm_nl_ctl
TEST_GEN_FILES = mptcp_connect pm_nl_ctl mptcp_sockopt
TEST_FILES := settings

View file

@ -0,0 +1,683 @@
// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <assert.h>
#include <errno.h>
#include <limits.h>
#include <string.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <netdb.h>
#include <netinet/in.h>
#include <linux/tcp.h>
static int pf = AF_INET;
#ifndef IPPROTO_MPTCP
#define IPPROTO_MPTCP 262
#endif
#ifndef SOL_MPTCP
#define SOL_MPTCP 284
#endif
#ifndef MPTCP_INFO
struct mptcp_info {
__u8 mptcpi_subflows;
__u8 mptcpi_add_addr_signal;
__u8 mptcpi_add_addr_accepted;
__u8 mptcpi_subflows_max;
__u8 mptcpi_add_addr_signal_max;
__u8 mptcpi_add_addr_accepted_max;
__u32 mptcpi_flags;
__u32 mptcpi_token;
__u64 mptcpi_write_seq;
__u64 mptcpi_snd_una;
__u64 mptcpi_rcv_nxt;
__u8 mptcpi_local_addr_used;
__u8 mptcpi_local_addr_max;
__u8 mptcpi_csum_enabled;
};
struct mptcp_subflow_data {
__u32 size_subflow_data; /* size of this structure in userspace */
__u32 num_subflows; /* must be 0, set by kernel */
__u32 size_kernel; /* must be 0, set by kernel */
__u32 size_user; /* size of one element in data[] */
} __attribute__((aligned(8)));
struct mptcp_subflow_addrs {
union {
__kernel_sa_family_t sa_family;
struct sockaddr sa_local;
struct sockaddr_in sin_local;
struct sockaddr_in6 sin6_local;
struct __kernel_sockaddr_storage ss_local;
};
union {
struct sockaddr sa_remote;
struct sockaddr_in sin_remote;
struct sockaddr_in6 sin6_remote;
struct __kernel_sockaddr_storage ss_remote;
};
};
#define MPTCP_INFO 1
#define MPTCP_TCPINFO 2
#define MPTCP_SUBFLOW_ADDRS 3
#endif
struct so_state {
struct mptcp_info mi;
uint64_t mptcpi_rcv_delta;
uint64_t tcpi_rcv_delta;
};
static void die_perror(const char *msg)
{
perror(msg);
exit(1);
}
static void die_usage(int r)
{
fprintf(stderr, "Usage: mptcp_sockopt [-6]\n");
exit(r);
}
static void xerror(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
fputc('\n', stderr);
exit(1);
}
static const char *getxinfo_strerr(int err)
{
if (err == EAI_SYSTEM)
return strerror(errno);
return gai_strerror(err);
}
static void xgetaddrinfo(const char *node, const char *service,
const struct addrinfo *hints,
struct addrinfo **res)
{
int err = getaddrinfo(node, service, hints, res);
if (err) {
const char *errstr = getxinfo_strerr(err);
fprintf(stderr, "Fatal: getaddrinfo(%s:%s): %s\n",
node ? node : "", service ? service : "", errstr);
exit(1);
}
}
static int sock_listen_mptcp(const char * const listenaddr,
const char * const port)
{
int sock;
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,
.ai_flags = AI_PASSIVE | AI_NUMERICHOST
};
hints.ai_family = pf;
struct addrinfo *a, *addr;
int one = 1;
xgetaddrinfo(listenaddr, port, &hints, &addr);
hints.ai_family = pf;
for (a = addr; a; a = a->ai_next) {
sock = socket(a->ai_family, a->ai_socktype, IPPROTO_MPTCP);
if (sock < 0)
continue;
if (-1 == setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &one,
sizeof(one)))
perror("setsockopt");
if (bind(sock, a->ai_addr, a->ai_addrlen) == 0)
break; /* success */
perror("bind");
close(sock);
sock = -1;
}
freeaddrinfo(addr);
if (sock < 0)
xerror("could not create listen socket");
if (listen(sock, 20))
die_perror("listen");
return sock;
}
static int sock_connect_mptcp(const char * const remoteaddr,
const char * const port, int proto)
{
struct addrinfo hints = {
.ai_protocol = IPPROTO_TCP,
.ai_socktype = SOCK_STREAM,
};
struct addrinfo *a, *addr;
int sock = -1;
hints.ai_family = pf;
xgetaddrinfo(remoteaddr, port, &hints, &addr);
for (a = addr; a; a = a->ai_next) {
sock = socket(a->ai_family, a->ai_socktype, proto);
if (sock < 0)
continue;
if (connect(sock, a->ai_addr, a->ai_addrlen) == 0)
break; /* success */
die_perror("connect");
}
if (sock < 0)
xerror("could not create connect socket");
freeaddrinfo(addr);
return sock;
}
static void parse_opts(int argc, char **argv)
{
int c;
while ((c = getopt(argc, argv, "h6")) != -1) {
switch (c) {
case 'h':
die_usage(0);
break;
case '6':
pf = AF_INET6;
break;
default:
die_usage(1);
break;
}
}
}
static void do_getsockopt_bogus_sf_data(int fd, int optname)
{
struct mptcp_subflow_data good_data;
struct bogus_data {
struct mptcp_subflow_data d;
char buf[2];
} bd;
socklen_t olen, _olen;
int ret;
memset(&bd, 0, sizeof(bd));
memset(&good_data, 0, sizeof(good_data));
olen = sizeof(good_data);
good_data.size_subflow_data = olen;
ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
assert(ret < 0); /* 0 size_subflow_data */
assert(olen == sizeof(good_data));
bd.d = good_data;
ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
assert(ret == 0);
assert(olen == sizeof(good_data));
assert(bd.d.num_subflows == 1);
assert(bd.d.size_kernel > 0);
assert(bd.d.size_user == 0);
bd.d = good_data;
_olen = rand() % olen;
olen = _olen;
ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
assert(ret < 0); /* bogus olen */
assert(olen == _olen); /* must be unchanged */
bd.d = good_data;
olen = sizeof(good_data);
bd.d.size_kernel = 1;
ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
assert(ret < 0); /* size_kernel not 0 */
bd.d = good_data;
olen = sizeof(good_data);
bd.d.num_subflows = 1;
ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
assert(ret < 0); /* num_subflows not 0 */
/* forward compat check: larger struct mptcp_subflow_data on 'old' kernel */
bd.d = good_data;
olen = sizeof(bd);
bd.d.size_subflow_data = sizeof(bd);
ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &olen);
assert(ret == 0);
/* olen must be truncated to real data size filled by kernel: */
assert(olen == sizeof(good_data));
assert(bd.d.size_subflow_data == sizeof(bd));
bd.d = good_data;
bd.d.size_subflow_data += 1;
bd.d.size_user = 1;
olen = bd.d.size_subflow_data + 1;
_olen = olen;
ret = getsockopt(fd, SOL_MPTCP, optname, &bd, &_olen);
assert(ret == 0);
/* no truncation, kernel should have filled 1 byte of optname payload in buf[1]: */
assert(olen == _olen);
assert(bd.d.size_subflow_data == sizeof(good_data) + 1);
assert(bd.buf[0] == 0);
}
static void do_getsockopt_mptcp_info(struct so_state *s, int fd, size_t w)
{
struct mptcp_info i;
socklen_t olen;
int ret;
olen = sizeof(i);
ret = getsockopt(fd, SOL_MPTCP, MPTCP_INFO, &i, &olen);
if (ret < 0)
die_perror("getsockopt MPTCP_INFO");
assert(olen == sizeof(i));
if (s->mi.mptcpi_write_seq == 0)
s->mi = i;
assert(s->mi.mptcpi_write_seq + w == i.mptcpi_write_seq);
s->mptcpi_rcv_delta = i.mptcpi_rcv_nxt - s->mi.mptcpi_rcv_nxt;
}
static void do_getsockopt_tcp_info(struct so_state *s, int fd, size_t r, size_t w)
{
struct my_tcp_info {
struct mptcp_subflow_data d;
struct tcp_info ti[2];
} ti;
int ret, tries = 5;
socklen_t olen;
do {
memset(&ti, 0, sizeof(ti));
ti.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
ti.d.size_user = sizeof(struct tcp_info);
olen = sizeof(ti);
ret = getsockopt(fd, SOL_MPTCP, MPTCP_TCPINFO, &ti, &olen);
if (ret < 0)
xerror("getsockopt MPTCP_TCPINFO (tries %d, %m)");
assert(olen <= sizeof(ti));
assert(ti.d.size_user == ti.d.size_kernel);
assert(ti.d.size_user == sizeof(struct tcp_info));
assert(ti.d.num_subflows == 1);
assert(olen > (socklen_t)sizeof(struct mptcp_subflow_data));
olen -= sizeof(struct mptcp_subflow_data);
assert(olen == sizeof(struct tcp_info));
if (ti.ti[0].tcpi_bytes_sent == w &&
ti.ti[0].tcpi_bytes_received == r)
goto done;
if (r == 0 && ti.ti[0].tcpi_bytes_sent == w &&
ti.ti[0].tcpi_bytes_received) {
s->tcpi_rcv_delta = ti.ti[0].tcpi_bytes_received;
goto done;
}
/* wait and repeat, might be that tx is still ongoing */
sleep(1);
} while (tries-- > 0);
xerror("tcpi_bytes_sent %" PRIu64 ", want %zu. tcpi_bytes_received %" PRIu64 ", want %zu",
ti.ti[0].tcpi_bytes_sent, w, ti.ti[0].tcpi_bytes_received, r);
done:
do_getsockopt_bogus_sf_data(fd, MPTCP_TCPINFO);
}
static void do_getsockopt_subflow_addrs(int fd)
{
struct sockaddr_storage remote, local;
socklen_t olen, rlen, llen;
int ret;
struct my_addrs {
struct mptcp_subflow_data d;
struct mptcp_subflow_addrs addr[2];
} addrs;
memset(&addrs, 0, sizeof(addrs));
memset(&local, 0, sizeof(local));
memset(&remote, 0, sizeof(remote));
addrs.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
addrs.d.size_user = sizeof(struct mptcp_subflow_addrs);
olen = sizeof(addrs);
ret = getsockopt(fd, SOL_MPTCP, MPTCP_SUBFLOW_ADDRS, &addrs, &olen);
if (ret < 0)
die_perror("getsockopt MPTCP_SUBFLOW_ADDRS");
assert(olen <= sizeof(addrs));
assert(addrs.d.size_user == addrs.d.size_kernel);
assert(addrs.d.size_user == sizeof(struct mptcp_subflow_addrs));
assert(addrs.d.num_subflows == 1);
assert(olen > (socklen_t)sizeof(struct mptcp_subflow_data));
olen -= sizeof(struct mptcp_subflow_data);
assert(olen == sizeof(struct mptcp_subflow_addrs));
llen = sizeof(local);
ret = getsockname(fd, (struct sockaddr *)&local, &llen);
if (ret < 0)
die_perror("getsockname");
rlen = sizeof(remote);
ret = getpeername(fd, (struct sockaddr *)&remote, &rlen);
if (ret < 0)
die_perror("getpeername");
assert(rlen > 0);
assert(rlen == llen);
assert(remote.ss_family == local.ss_family);
assert(memcmp(&local, &addrs.addr[0].ss_local, sizeof(local)) == 0);
assert(memcmp(&remote, &addrs.addr[0].ss_remote, sizeof(remote)) == 0);
memset(&addrs, 0, sizeof(addrs));
addrs.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
addrs.d.size_user = sizeof(sa_family_t);
olen = sizeof(addrs.d) + sizeof(sa_family_t);
ret = getsockopt(fd, SOL_MPTCP, MPTCP_SUBFLOW_ADDRS, &addrs, &olen);
assert(ret == 0);
assert(olen == sizeof(addrs.d) + sizeof(sa_family_t));
assert(addrs.addr[0].sa_family == pf);
assert(addrs.addr[0].sa_family == local.ss_family);
assert(memcmp(&local, &addrs.addr[0].ss_local, sizeof(local)) != 0);
assert(memcmp(&remote, &addrs.addr[0].ss_remote, sizeof(remote)) != 0);
do_getsockopt_bogus_sf_data(fd, MPTCP_SUBFLOW_ADDRS);
}
static void do_getsockopts(struct so_state *s, int fd, size_t r, size_t w)
{
do_getsockopt_mptcp_info(s, fd, w);
do_getsockopt_tcp_info(s, fd, r, w);
do_getsockopt_subflow_addrs(fd);
}
static void connect_one_server(int fd, int pipefd)
{
char buf[4096], buf2[4096];
size_t len, i, total;
struct so_state s;
bool eof = false;
ssize_t ret;
memset(&s, 0, sizeof(s));
len = rand() % (sizeof(buf) - 1);
if (len < 128)
len = 128;
for (i = 0; i < len ; i++) {
buf[i] = rand() % 26;
buf[i] += 'A';
}
buf[i] = '\n';
do_getsockopts(&s, fd, 0, 0);
/* un-block server */
ret = read(pipefd, buf2, 4);
assert(ret == 4);
close(pipefd);
assert(strncmp(buf2, "xmit", 4) == 0);
ret = write(fd, buf, len);
if (ret < 0)
die_perror("write");
if (ret != (ssize_t)len)
xerror("short write");
total = 0;
do {
ret = read(fd, buf2 + total, sizeof(buf2) - total);
if (ret < 0)
die_perror("read");
if (ret == 0) {
eof = true;
break;
}
total += ret;
} while (total < len);
if (total != len)
xerror("total %lu, len %lu eof %d\n", total, len, eof);
if (memcmp(buf, buf2, len))
xerror("data corruption");
if (s.tcpi_rcv_delta)
assert(s.tcpi_rcv_delta <= total);
do_getsockopts(&s, fd, ret, ret);
if (eof)
total += 1; /* sequence advances due to FIN */
assert(s.mptcpi_rcv_delta == (uint64_t)total);
close(fd);
}
static void process_one_client(int fd, int pipefd)
{
ssize_t ret, ret2, ret3;
struct so_state s;
char buf[4096];
memset(&s, 0, sizeof(s));
do_getsockopts(&s, fd, 0, 0);
ret = write(pipefd, "xmit", 4);
assert(ret == 4);
ret = read(fd, buf, sizeof(buf));
if (ret < 0)
die_perror("read");
assert(s.mptcpi_rcv_delta <= (uint64_t)ret);
if (s.tcpi_rcv_delta)
assert(s.tcpi_rcv_delta == (uint64_t)ret);
ret2 = write(fd, buf, ret);
if (ret2 < 0)
die_perror("write");
/* wait for hangup */
ret3 = read(fd, buf, 1);
if (ret3 != 0)
xerror("expected EOF, got %lu", ret3);
do_getsockopts(&s, fd, ret, ret2);
if (s.mptcpi_rcv_delta != (uint64_t)ret + 1)
xerror("mptcpi_rcv_delta %" PRIu64 ", expect %" PRIu64, s.mptcpi_rcv_delta, ret + 1, s.mptcpi_rcv_delta - ret);
close(fd);
}
static int xaccept(int s)
{
int fd = accept(s, NULL, 0);
if (fd < 0)
die_perror("accept");
return fd;
}
static int server(int pipefd)
{
int fd = -1, r;
switch (pf) {
case AF_INET:
fd = sock_listen_mptcp("127.0.0.1", "15432");
break;
case AF_INET6:
fd = sock_listen_mptcp("::1", "15432");
break;
default:
xerror("Unknown pf %d\n", pf);
break;
}
r = write(pipefd, "conn", 4);
assert(r == 4);
alarm(15);
r = xaccept(fd);
process_one_client(r, pipefd);
return 0;
}
static int client(int pipefd)
{
int fd = -1;
alarm(15);
switch (pf) {
case AF_INET:
fd = sock_connect_mptcp("127.0.0.1", "15432", IPPROTO_MPTCP);
break;
case AF_INET6:
fd = sock_connect_mptcp("::1", "15432", IPPROTO_MPTCP);
break;
default:
xerror("Unknown pf %d\n", pf);
}
connect_one_server(fd, pipefd);
return 0;
}
static pid_t xfork(void)
{
pid_t p = fork();
if (p < 0)
die_perror("fork");
return p;
}
static int rcheck(int wstatus, const char *what)
{
if (WIFEXITED(wstatus)) {
if (WEXITSTATUS(wstatus) == 0)
return 0;
fprintf(stderr, "%s exited, status=%d\n", what, WEXITSTATUS(wstatus));
return WEXITSTATUS(wstatus);
} else if (WIFSIGNALED(wstatus)) {
xerror("%s killed by signal %d\n", what, WTERMSIG(wstatus));
} else if (WIFSTOPPED(wstatus)) {
xerror("%s stopped by signal %d\n", what, WSTOPSIG(wstatus));
}
return 111;
}
int main(int argc, char *argv[])
{
int e1, e2, wstatus;
pid_t s, c, ret;
int pipefds[2];
parse_opts(argc, argv);
e1 = pipe(pipefds);
if (e1 < 0)
die_perror("pipe");
s = xfork();
if (s == 0)
return server(pipefds[1]);
close(pipefds[1]);
/* wait until server bound a socket */
e1 = read(pipefds[0], &e1, 4);
assert(e1 == 4);
c = xfork();
if (c == 0)
return client(pipefds[0]);
close(pipefds[0]);
ret = waitpid(s, &wstatus, 0);
if (ret == -1)
die_perror("waitpid");
e1 = rcheck(wstatus, "server");
ret = waitpid(c, &wstatus, 0);
if (ret == -1)
die_perror("waitpid");
e2 = rcheck(wstatus, "client");
return e1 ? e1 : e2;
}

View file

@ -239,12 +239,35 @@ make_file()
echo "Created $name (size $size KB) containing data sent by $who"
}
do_mptcp_sockopt_tests()
{
local lret=0
./mptcp_sockopt
lret=$?
if [ $lret -ne 0 ]; then
echo "FAIL: SOL_MPTCP getsockopt" 1>&2
ret=$lret
return
fi
./mptcp_sockopt -6
lret=$?
if [ $lret -ne 0 ]; then
echo "FAIL: SOL_MPTCP getsockopt (ipv6)" 1>&2
ret=$lret
return
fi
}
run_tests()
{
listener_ns="$1"
connector_ns="$2"
connect_addr="$3"
lret=0
local lret=0
do_transfer ${listener_ns} ${connector_ns} MPTCP MPTCP ${connect_addr}
@ -268,9 +291,13 @@ trap cleanup EXIT
run_tests $ns1 $ns2 10.0.1.1
run_tests $ns1 $ns2 dead:beef:1::1
if [ $ret -eq 0 ];then
echo "PASS: all packets had packet mark set"
fi
do_mptcp_sockopt_tests
if [ $ret -eq 0 ];then
echo "PASS: SOL_MPTCP getsockopt has expected information"
fi
exit $ret