// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018 Facebook
// Copyright (c) 2019 Cloudflare
// Copyright (c) 2020 Isovalent, Inc.
/*
* Test that the socket assign program is able to redirect traffic towards a
* socket, regardless of whether the port or address destination of the traffic
* matches the port.
*/
#define _GNU_SOURCE
#include <fcntl.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include "test_progs.h"
#include "network_helpers.h"
#define BIND_PORT 1234
#define CONNECT_PORT 4321
#define TEST_DADDR (0xC0A80203)
#define NS_SELF "/proc/self/ns/net"
#define SERVER_MAP_PATH "/sys/fs/bpf/tc/globals/server_map"
static int stop, duration;
static bool
configure_stack(void)
{
char tc_version[128];
char tc_cmd[BUFSIZ];
char *prog;
FILE *tc;
/* Check whether tc is built with libbpf. */
tc = popen("tc -V", "r");
if (CHECK_FAIL(!tc))
return false;
if (CHECK_FAIL(!fgets(tc_version, sizeof(tc_version), tc)))
return false;
if (strstr(tc_version, ", libbpf "))
prog = "test_sk_assign_libbpf.bpf.o";
else
prog = "test_sk_assign.bpf.o";
if (CHECK_FAIL(pclose(tc)))
return false;
/* Move to a new networking namespace */
if (CHECK_FAIL(unshare(CLONE_NEWNET)))
return false;
/* Configure necessary links, routes */
if (CHECK_FAIL(system("ip link set dev lo up")))
return false;
if (CHECK_FAIL(system("ip route add local default dev lo")))
return false;
if (CHECK_FAIL(system("ip -6 route add local default dev lo")))
return false;
/* Load qdisc, BPF program */
if (CHECK_FAIL(system("tc qdisc add dev lo clsact")))
return false;
sprintf(tc_cmd, "%s %s %s %s %s", "tc filter add dev lo ingress bpf",
"direct-action object-file", prog,
"section tc",
(env.verbosity < VERBOSE_VERY) ? " 2>/dev/null" : "verbose");
if (CHECK(system(tc_cmd), "BPF load failed;",
"run with -vv for more info\n"))
return false;
return true;
}
static in_port_t
get_port(int fd)
{
struct sockaddr_storage ss;
socklen_t slen = sizeof(ss);
in_port_t port = 0;
if (CHECK_FAIL(getsockname(fd, (struct sockaddr *)&ss, &slen)))
return port;
switch (ss.ss_family) {
case AF_INET:
port = ((struct sockaddr_in *)&ss)->sin_port;
break;
case AF_INET6:
port = ((struct sockaddr_in6 *)&ss)->sin6_port;
break;
default:
CHECK(1, "Invalid address family", "%d\n", ss.ss_family);
}
return port;
}
static ssize_t
rcv_msg(int srv_client, int type)
{
char buf[BUFSIZ];
if (type == SOCK_STREAM)
return read(srv_client, &buf, sizeof(buf));
else
return recvfrom(srv_client, &buf, sizeof(buf), 0, NULL, NULL);
}
static int
run_test(int server_fd, const struct sockaddr *addr, socklen_t len, int type)
{
int client = -1, srv_client = -1;
char buf[] = "testing";
in_port_t port;
int ret = 1;
client = connect_to_addr(type, (struct sockaddr_storage *)addr, len, NULL);
if (client == -1) {
perror("Cannot connect to server");
goto out;
}
if (type == SOCK_STREAM) {
srv_client = accept(server_fd, NULL, NULL);
if (CHECK_FAIL(srv_client == -1)) {
perror("Can't accept connection");
goto out;
}
} else {
srv_client = server_fd;
}
if (CHECK_FAIL(write(client, buf, sizeof(buf)) != sizeof(buf))) {
perror("Can't write on client");
goto out;
}
if (CHECK_FAIL(rcv_msg(srv_client, type) != sizeof(buf))) {
perror("Can't read on server");
goto out;
}
port = get_port(srv_client);
if (CHECK_FAIL(!port))
goto out;
/* SOCK_STREAM is connected via accept(), so the server's local address
* will be the CONNECT_PORT rather than the BIND port that corresponds
* to the listen socket. SOCK_DGRAM on the other hand is connectionless
* so we can't really do the same check there; the server doesn't ever
* create a socket with CONNECT_PORT.
*/
if (type == SOCK_STREAM &&
CHECK(port != htons(CONNECT_PORT), "Expected", "port %u but got %u",
CONNECT_PORT, ntohs(port)))
goto out;
else if (type == SOCK_DGRAM &&
CHECK(port != htons(BIND_PORT), "Expected",
"port %u but got %u", BIND_PORT, ntohs(port)))
goto out;
ret = 0;
out:
close(client);
if (srv_client != server_fd)
close(srv_client);
if (ret)
WRITE_ONCE(stop, 1);
return ret;
}
static void
prepare_addr(struct sockaddr *addr, int family, __u16 port, bool rewrite_addr)
{
struct sockaddr_in *addr4;
struct sockaddr_in6 *addr6;
switch (family) {
case AF_INET:
addr4 = (struct sockaddr_in *)addr;
memset(addr4, 0, sizeof(*addr4));
addr4->sin_family = family;
addr4->sin_port = htons(port);
if (rewrite_addr)
addr4->sin_addr.s_addr = htonl(TEST_DADDR);
else
addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
break;
case AF_INET6:
addr6 = (struct sockaddr_in6 *)addr;
memset(addr6, 0, sizeof(*addr6));
addr6->sin6_family = family;
addr6->sin6_port = htons(port);
addr6->sin6_addr = in6addr_loopback;
if (rewrite_addr)
addr6->sin6_addr.s6_addr32[3] = htonl(TEST_DADDR);
break;
default:
fprintf(stderr, "Invalid family %d", family);
}
}
struct test_sk_cfg {
const char *name;
int family;
struct sockaddr *addr;
socklen_t len;
int type;
bool rewrite_addr;
};
#define TEST(NAME, FAMILY, TYPE, REWRITE) \
{ \
.name = NAME, \
.family = FAMILY, \
.addr = (FAMILY == AF_INET) ? (struct sockaddr *)&addr4 \
: (struct sockaddr *)&addr6, \
.len = (FAMILY == AF_INET) ? sizeof(addr4) : sizeof(addr6), \
.type = TYPE, \
.rewrite_addr = REWRITE, \
}
void test_sk_assign(void)
{
struct sockaddr_in addr4;
struct sockaddr_in6 addr6;
struct test_sk_cfg tests[] = {
TEST("ipv4 tcp port redir", AF_INET, SOCK_STREAM, false),
TEST("ipv4 tcp addr redir", AF_INET, SOCK_STREAM, true),
TEST("ipv6 tcp port redir", AF_INET6, SOCK_STREAM, false),
TEST("ipv6 tcp addr redir", AF_INET6, SOCK_STREAM, true),
TEST("ipv4 udp port redir", AF_INET, SOCK_DGRAM, false),
TEST("ipv4 udp addr redir", AF_INET, SOCK_DGRAM, true),
TEST("ipv6 udp port redir", AF_INET6, SOCK_DGRAM, false),
TEST("ipv6 udp addr redir", AF_INET6, SOCK_DGRAM, true),
};
__s64 server = -1;
int server_map;
int self_net;
int i;
self_net = open(NS_SELF, O_RDONLY);
if (CHECK_FAIL(self_net < 0)) {
perror("Unable to open "NS_SELF);
return;
}
if (!configure_stack()) {
perror("configure_stack");
goto cleanup;
}
server_map = bpf_obj_get(SERVER_MAP_PATH);
if (CHECK_FAIL(server_map < 0)) {
perror("Unable to open " SERVER_MAP_PATH);
goto cleanup;
}
for (i = 0; i < ARRAY_SIZE(tests) && !READ_ONCE(stop); i++) {
struct test_sk_cfg *test = &tests[i];
const struct sockaddr *addr;
const int zero = 0;
int err;
if (!test__start_subtest(test->name))
continue;
prepare_addr(test->addr, test->family, BIND_PORT, false);
addr = (const struct sockaddr *)test->addr;
server = start_server_addr(test->type,
(const struct sockaddr_storage *)addr,
test->len, NULL);
if (server == -1)
goto close;
err = bpf_map_update_elem(server_map, &zero, &server, BPF_ANY);
if (CHECK_FAIL(err)) {
perror("Unable to update server_map");
goto close;
}
/* connect to unbound ports */
prepare_addr(test->addr, test->family, CONNECT_PORT,
test->rewrite_addr);
if (run_test(server, addr, test->len, test->type))
goto close;
close(server);
server = -1;
}
close:
close(server);
close(server_map);
cleanup:
if (CHECK_FAIL(unlink(SERVER_MAP_PATH)))
perror("Unable to unlink " SERVER_MAP_PATH);
if (CHECK_FAIL(setns(self_net, CLONE_NEWNET)))
perror("Failed to setns("NS_SELF")");
close(self_net);
}
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