// 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" 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);	__u32 cookie_value;	__u64 cookie_key;	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_get_next_key(map_fd, NULL, &cookie_key);	if (err) {		log_err("Can't get cookie key from map");		goto out;	} 	err = bpf_map_lookup_elem(map_fd, &cookie_key, &cookie_value);	if (err) {		log_err("Can't get cookie value from map");		goto out;	} 	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 (cookie_value != cookie_expected_value) {		log_err("Unexpected value in map: %x != %x", 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; 	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__title(prog, /*needs_copy*/ false); 		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; 	if (setup_cgroup_environment())		goto err; 	cgfd = create_and_get_cgroup(CG_PATH);	if (cgfd < 0)		goto err; 	if (join_cgroup(CG_PATH))		goto err; 	if (run_test(cgfd))		goto err; 	goto out;err:	err = -1;out:	close(cgfd);	cleanup_cgroup_environment();	return err;}