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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#define _GNU_SOURCE
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sched.h>
#include <linux/compiler.h>
#include <bpf/libbpf.h>
#include "network_helpers.h"
#include "test_progs.h"
#include "test_btf_skc_cls_ingress.skel.h"
static struct test_btf_skc_cls_ingress *skel;
static struct sockaddr_in6 srv_sa6;
static __u32 duration;
#define PROG_PIN_FILE "/sys/fs/bpf/btf_skc_cls_ingress"
static int write_sysctl(const char *sysctl, const char *value)
{
int fd, err, len;
fd = open(sysctl, O_WRONLY);
if (CHECK(fd == -1, "open sysctl", "open(%s): %s (%d)\n",
sysctl, strerror(errno), errno))
return -1;
len = strlen(value);
err = write(fd, value, len);
close(fd);
if (CHECK(err != len, "write sysctl",
"write(%s, %s, %d): err:%d %s (%d)\n",
sysctl, value, len, err, strerror(errno), errno))
return -1;
return 0;
}
static int prepare_netns(void)
{
if (CHECK(unshare(CLONE_NEWNET), "create netns",
"unshare(CLONE_NEWNET): %s (%d)",
strerror(errno), errno))
return -1;
if (CHECK(system("ip link set dev lo up"),
"ip link set dev lo up", "failed\n"))
return -1;
if (CHECK(system("tc qdisc add dev lo clsact"),
"tc qdisc add dev lo clsact", "failed\n"))
return -1;
if (CHECK(system("tc filter add dev lo ingress bpf direct-action object-pinned " PROG_PIN_FILE),
"install tc cls-prog at ingress", "failed\n"))
return -1;
/* Ensure 20 bytes options (i.e. in total 40 bytes tcp header) for the
* bpf_tcp_gen_syncookie() helper.
*/
if (write_sysctl("/proc/sys/net/ipv4/tcp_window_scaling", "1") ||
write_sysctl("/proc/sys/net/ipv4/tcp_timestamps", "1") ||
write_sysctl("/proc/sys/net/ipv4/tcp_sack", "1"))
return -1;
return 0;
}
static void reset_test(void)
{
memset(&skel->bss->srv_sa6, 0, sizeof(skel->bss->srv_sa6));
skel->bss->listen_tp_sport = 0;
skel->bss->req_sk_sport = 0;
skel->bss->recv_cookie = 0;
skel->bss->gen_cookie = 0;
skel->bss->linum = 0;
}
static void print_err_line(void)
{
if (skel->bss->linum)
printf("bpf prog error at line %u\n", skel->bss->linum);
}
static void test_conn(void)
{
int listen_fd = -1, cli_fd = -1, err;
socklen_t addrlen = sizeof(srv_sa6);
int srv_port;
if (write_sysctl("/proc/sys/net/ipv4/tcp_syncookies", "1"))
return;
listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
if (CHECK_FAIL(listen_fd == -1))
return;
err = getsockname(listen_fd, (struct sockaddr *)&srv_sa6, &addrlen);
if (CHECK(err, "getsockname(listen_fd)", "err:%d errno:%d\n", err,
errno))
goto done;
memcpy(&skel->bss->srv_sa6, &srv_sa6, sizeof(srv_sa6));
srv_port = ntohs(srv_sa6.sin6_port);
cli_fd = connect_to_fd(listen_fd, 0);
if (CHECK_FAIL(cli_fd == -1))
goto done;
if (CHECK(skel->bss->listen_tp_sport != srv_port ||
skel->bss->req_sk_sport != srv_port,
"Unexpected sk src port",
"listen_tp_sport:%u req_sk_sport:%u expected:%u\n",
skel->bss->listen_tp_sport, skel->bss->req_sk_sport,
srv_port))
goto done;
if (CHECK(skel->bss->gen_cookie || skel->bss->recv_cookie,
"Unexpected syncookie states",
"gen_cookie:%u recv_cookie:%u\n",
skel->bss->gen_cookie, skel->bss->recv_cookie))
goto done;
CHECK(skel->bss->linum, "bpf prog detected error", "at line %u\n",
skel->bss->linum);
done:
if (listen_fd != -1)
close(listen_fd);
if (cli_fd != -1)
close(cli_fd);
}
static void test_syncookie(void)
{
int listen_fd = -1, cli_fd = -1, err;
socklen_t addrlen = sizeof(srv_sa6);
int srv_port;
/* Enforce syncookie mode */
if (write_sysctl("/proc/sys/net/ipv4/tcp_syncookies", "2"))
return;
listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
if (CHECK_FAIL(listen_fd == -1))
return;
err = getsockname(listen_fd, (struct sockaddr *)&srv_sa6, &addrlen);
if (CHECK(err, "getsockname(listen_fd)", "err:%d errno:%d\n", err,
errno))
goto done;
memcpy(&skel->bss->srv_sa6, &srv_sa6, sizeof(srv_sa6));
srv_port = ntohs(srv_sa6.sin6_port);
cli_fd = connect_to_fd(listen_fd, 0);
if (CHECK_FAIL(cli_fd == -1))
goto done;
if (CHECK(skel->bss->listen_tp_sport != srv_port,
"Unexpected tp src port",
"listen_tp_sport:%u expected:%u\n",
skel->bss->listen_tp_sport, srv_port))
goto done;
if (CHECK(skel->bss->req_sk_sport,
"Unexpected req_sk src port",
"req_sk_sport:%u expected:0\n",
skel->bss->req_sk_sport))
goto done;
if (CHECK(!skel->bss->gen_cookie ||
skel->bss->gen_cookie != skel->bss->recv_cookie,
"Unexpected syncookie states",
"gen_cookie:%u recv_cookie:%u\n",
skel->bss->gen_cookie, skel->bss->recv_cookie))
goto done;
CHECK(skel->bss->linum, "bpf prog detected error", "at line %u\n",
skel->bss->linum);
done:
if (listen_fd != -1)
close(listen_fd);
if (cli_fd != -1)
close(cli_fd);
}
struct test {
const char *desc;
void (*run)(void);
};
#define DEF_TEST(name) { #name, test_##name }
static struct test tests[] = {
DEF_TEST(conn),
DEF_TEST(syncookie),
};
void test_btf_skc_cls_ingress(void)
{
int i, err;
skel = test_btf_skc_cls_ingress__open_and_load();
if (CHECK(!skel, "test_btf_skc_cls_ingress__open_and_load", "failed\n"))
return;
err = bpf_program__pin(skel->progs.cls_ingress, PROG_PIN_FILE);
if (CHECK(err, "bpf_program__pin",
"cannot pin bpf prog to %s. err:%d\n", PROG_PIN_FILE, err)) {
test_btf_skc_cls_ingress__destroy(skel);
return;
}
for (i = 0; i < ARRAY_SIZE(tests); i++) {
if (!test__start_subtest(tests[i].desc))
continue;
if (prepare_netns())
break;
tests[i].run();
print_err_line();
reset_test();
}
bpf_program__unpin(skel->progs.cls_ingress, PROG_PIN_FILE);
test_btf_skc_cls_ingress__destroy(skel);
}
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