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// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018 Facebook
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#include "bpf_rlimit.h"
#include "cgroup_helpers.h"
#define CG_PATH "/foo"
#define SOCKET_COOKIE_PROG "./socket_cookie_prog.o"
struct socket_cookie {
__u64 cookie_key;
__u32 cookie_value;
};
static int start_server(void)
{
struct sockaddr_in6 addr;
int fd;
fd = socket(AF_INET6, SOCK_STREAM, 0);
if (fd == -1) {
log_err("Failed to create server socket");
goto out;
}
memset(&addr, 0, sizeof(addr));
addr.sin6_family = AF_INET6;
addr.sin6_addr = in6addr_loopback;
addr.sin6_port = 0;
if (bind(fd, (const struct sockaddr *)&addr, sizeof(addr)) == -1) {
log_err("Failed to bind server socket");
goto close_out;
}
if (listen(fd, 128) == -1) {
log_err("Failed to listen on server socket");
goto close_out;
}
goto out;
close_out:
close(fd);
fd = -1;
out:
return fd;
}
static int connect_to_server(int server_fd)
{
struct sockaddr_storage addr;
socklen_t len = sizeof(addr);
int fd;
fd = socket(AF_INET6, SOCK_STREAM, 0);
if (fd == -1) {
log_err("Failed to create client socket");
goto out;
}
if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
log_err("Failed to get server addr");
goto close_out;
}
if (connect(fd, (const struct sockaddr *)&addr, len) == -1) {
log_err("Fail to connect to server");
goto close_out;
}
goto out;
close_out:
close(fd);
fd = -1;
out:
return fd;
}
static int validate_map(struct bpf_map *map, int client_fd)
{
__u32 cookie_expected_value;
struct sockaddr_in6 addr;
socklen_t len = sizeof(addr);
struct socket_cookie val;
int err = 0;
int map_fd;
if (!map) {
log_err("Map not found in BPF object");
goto err;
}
map_fd = bpf_map__fd(map);
err = bpf_map_lookup_elem(map_fd, &client_fd, &val);
err = getsockname(client_fd, (struct sockaddr *)&addr, &len);
if (err) {
log_err("Can't get client local addr");
goto out;
}
cookie_expected_value = (ntohs(addr.sin6_port) << 8) | 0xFF;
if (val.cookie_value != cookie_expected_value) {
log_err("Unexpected value in map: %x != %x", val.cookie_value,
cookie_expected_value);
goto err;
}
goto out;
err:
err = -1;
out:
return err;
}
static int run_test(int cgfd)
{
enum bpf_attach_type attach_type;
struct bpf_prog_load_attr attr;
struct bpf_program *prog;
struct bpf_object *pobj;
const char *prog_name;
int server_fd = -1;
int client_fd = -1;
int prog_fd = -1;
int err = 0;
memset(&attr, 0, sizeof(attr));
attr.file = SOCKET_COOKIE_PROG;
attr.prog_type = BPF_PROG_TYPE_UNSPEC;
attr.prog_flags = BPF_F_TEST_RND_HI32;
err = bpf_prog_load_xattr(&attr, &pobj, &prog_fd);
if (err) {
log_err("Failed to load %s", attr.file);
goto out;
}
bpf_object__for_each_program(prog, pobj) {
prog_name = bpf_program__section_name(prog);
if (libbpf_attach_type_by_name(prog_name, &attach_type))
goto err;
err = bpf_prog_attach(bpf_program__fd(prog), cgfd, attach_type,
BPF_F_ALLOW_OVERRIDE);
if (err) {
log_err("Failed to attach prog %s", prog_name);
goto out;
}
}
server_fd = start_server();
if (server_fd == -1)
goto err;
client_fd = connect_to_server(server_fd);
if (client_fd == -1)
goto err;
if (validate_map(bpf_map__next(NULL, pobj), client_fd))
goto err;
goto out;
err:
err = -1;
out:
close(client_fd);
close(server_fd);
bpf_object__close(pobj);
printf("%s\n", err ? "FAILED" : "PASSED");
return err;
}
int main(int argc, char **argv)
{
int cgfd = -1;
int err = 0;
cgfd = cgroup_setup_and_join(CG_PATH);
if (cgfd < 0)
goto err;
if (run_test(cgfd))
goto err;
goto out;
err:
err = -1;
out:
close(cgfd);
cleanup_cgroup_environment();
return err;
}
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