selftests/bpf: test BPF_SOCK_OPS_RTT_CB

Make sure the callback is invoked for syn-ack and data packet.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Priyaranjan Jha <priyarjha@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Stanislav Fomichev 2019-07-02 09:14:01 -07:00 committed by Daniel Borkmann
parent 692cbaa99f
commit b55873984d
3 changed files with 317 additions and 1 deletions

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@ -27,7 +27,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
test_cgroup_storage test_select_reuseport test_section_names \
test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
test_btf_dump test_cgroup_attach xdping test_sockopt test_sockopt_sk \
test_sockopt_multi
test_sockopt_multi test_tcp_rtt
BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
TEST_GEN_FILES = $(BPF_OBJ_FILES)
@ -107,6 +107,7 @@ $(OUTPUT)/test_cgroup_attach: cgroup_helpers.c
$(OUTPUT)/test_sockopt: cgroup_helpers.c
$(OUTPUT)/test_sockopt_sk: cgroup_helpers.c
$(OUTPUT)/test_sockopt_multi: cgroup_helpers.c
$(OUTPUT)/test_tcp_rtt: cgroup_helpers.c
.PHONY: force

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@ -0,0 +1,61 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
__u32 _version SEC("version") = 1;
struct tcp_rtt_storage {
__u32 invoked;
__u32 dsack_dups;
__u32 delivered;
__u32 delivered_ce;
__u32 icsk_retransmits;
};
struct bpf_map_def SEC("maps") socket_storage_map = {
.type = BPF_MAP_TYPE_SK_STORAGE,
.key_size = sizeof(int),
.value_size = sizeof(struct tcp_rtt_storage),
.map_flags = BPF_F_NO_PREALLOC,
};
BPF_ANNOTATE_KV_PAIR(socket_storage_map, int, struct tcp_rtt_storage);
SEC("sockops")
int _sockops(struct bpf_sock_ops *ctx)
{
struct tcp_rtt_storage *storage;
struct bpf_tcp_sock *tcp_sk;
int op = (int) ctx->op;
struct bpf_sock *sk;
sk = ctx->sk;
if (!sk)
return 1;
storage = bpf_sk_storage_get(&socket_storage_map, sk, 0,
BPF_SK_STORAGE_GET_F_CREATE);
if (!storage)
return 1;
if (op == BPF_SOCK_OPS_TCP_CONNECT_CB) {
bpf_sock_ops_cb_flags_set(ctx, BPF_SOCK_OPS_RTT_CB_FLAG);
return 1;
}
if (op != BPF_SOCK_OPS_RTT_CB)
return 1;
tcp_sk = bpf_tcp_sock(sk);
if (!tcp_sk)
return 1;
storage->invoked++;
storage->dsack_dups = tcp_sk->dsack_dups;
storage->delivered = tcp_sk->delivered;
storage->delivered_ce = tcp_sk->delivered_ce;
storage->icsk_retransmits = tcp_sk->icsk_retransmits;
return 1;
}

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@ -0,0 +1,254 @@
// SPDX-License-Identifier: GPL-2.0
#include <error.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <pthread.h>
#include <linux/filter.h>
#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#include "bpf_rlimit.h"
#include "bpf_util.h"
#include "cgroup_helpers.h"
#define CG_PATH "/tcp_rtt"
struct tcp_rtt_storage {
__u32 invoked;
__u32 dsack_dups;
__u32 delivered;
__u32 delivered_ce;
__u32 icsk_retransmits;
};
static void send_byte(int fd)
{
char b = 0x55;
if (write(fd, &b, sizeof(b)) != 1)
error(1, errno, "Failed to send single byte");
}
static int verify_sk(int map_fd, int client_fd, const char *msg, __u32 invoked,
__u32 dsack_dups, __u32 delivered, __u32 delivered_ce,
__u32 icsk_retransmits)
{
int err = 0;
struct tcp_rtt_storage val;
if (bpf_map_lookup_elem(map_fd, &client_fd, &val) < 0)
error(1, errno, "Failed to read socket storage");
if (val.invoked != invoked) {
log_err("%s: unexpected bpf_tcp_sock.invoked %d != %d",
msg, val.invoked, invoked);
err++;
}
if (val.dsack_dups != dsack_dups) {
log_err("%s: unexpected bpf_tcp_sock.dsack_dups %d != %d",
msg, val.dsack_dups, dsack_dups);
err++;
}
if (val.delivered != delivered) {
log_err("%s: unexpected bpf_tcp_sock.delivered %d != %d",
msg, val.delivered, delivered);
err++;
}
if (val.delivered_ce != delivered_ce) {
log_err("%s: unexpected bpf_tcp_sock.delivered_ce %d != %d",
msg, val.delivered_ce, delivered_ce);
err++;
}
if (val.icsk_retransmits != icsk_retransmits) {
log_err("%s: unexpected bpf_tcp_sock.icsk_retransmits %d != %d",
msg, val.icsk_retransmits, icsk_retransmits);
err++;
}
return err;
}
static int connect_to_server(int server_fd)
{
struct sockaddr_storage addr;
socklen_t len = sizeof(addr);
int fd;
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0) {
log_err("Failed to create client socket");
return -1;
}
if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
log_err("Failed to get server addr");
goto out;
}
if (connect(fd, (const struct sockaddr *)&addr, len) < 0) {
log_err("Fail to connect to server");
goto out;
}
return fd;
out:
close(fd);
return -1;
}
static int run_test(int cgroup_fd, int server_fd)
{
struct bpf_prog_load_attr attr = {
.prog_type = BPF_PROG_TYPE_SOCK_OPS,
.file = "./tcp_rtt.o",
.expected_attach_type = BPF_CGROUP_SOCK_OPS,
};
struct bpf_object *obj;
struct bpf_map *map;
int client_fd;
int prog_fd;
int map_fd;
int err;
err = bpf_prog_load_xattr(&attr, &obj, &prog_fd);
if (err) {
log_err("Failed to load BPF object");
return -1;
}
map = bpf_map__next(NULL, obj);
map_fd = bpf_map__fd(map);
err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0);
if (err) {
log_err("Failed to attach BPF program");
goto close_bpf_object;
}
client_fd = connect_to_server(server_fd);
if (client_fd < 0) {
err = -1;
goto close_bpf_object;
}
err += verify_sk(map_fd, client_fd, "syn-ack",
/*invoked=*/1,
/*dsack_dups=*/0,
/*delivered=*/1,
/*delivered_ce=*/0,
/*icsk_retransmits=*/0);
send_byte(client_fd);
err += verify_sk(map_fd, client_fd, "first payload byte",
/*invoked=*/2,
/*dsack_dups=*/0,
/*delivered=*/2,
/*delivered_ce=*/0,
/*icsk_retransmits=*/0);
close(client_fd);
close_bpf_object:
bpf_object__close(obj);
return err;
}
static int start_server(void)
{
struct sockaddr_in addr = {
.sin_family = AF_INET,
.sin_addr.s_addr = htonl(INADDR_LOOPBACK),
};
int fd;
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0) {
log_err("Failed to create server socket");
return -1;
}
if (bind(fd, (const struct sockaddr *)&addr, sizeof(addr)) < 0) {
log_err("Failed to bind socket");
close(fd);
return -1;
}
return fd;
}
static void *server_thread(void *arg)
{
struct sockaddr_storage addr;
socklen_t len = sizeof(addr);
int fd = *(int *)arg;
int client_fd;
if (listen(fd, 1) < 0)
error(1, errno, "Failed to listed on socket");
client_fd = accept(fd, (struct sockaddr *)&addr, &len);
if (client_fd < 0)
error(1, errno, "Failed to accept client");
/* Wait for the next connection (that never arrives)
* to keep this thread alive to prevent calling
* close() on client_fd.
*/
if (accept(fd, (struct sockaddr *)&addr, &len) >= 0)
error(1, errno, "Unexpected success in second accept");
close(client_fd);
return NULL;
}
int main(int args, char **argv)
{
int server_fd, cgroup_fd;
int err = EXIT_SUCCESS;
pthread_t tid;
if (setup_cgroup_environment())
goto cleanup_obj;
cgroup_fd = create_and_get_cgroup(CG_PATH);
if (cgroup_fd < 0)
goto cleanup_cgroup_env;
if (join_cgroup(CG_PATH))
goto cleanup_cgroup;
server_fd = start_server();
if (server_fd < 0) {
err = EXIT_FAILURE;
goto cleanup_cgroup;
}
pthread_create(&tid, NULL, server_thread, (void *)&server_fd);
if (run_test(cgroup_fd, server_fd))
err = EXIT_FAILURE;
close(server_fd);
printf("test_sockopt_sk: %s\n",
err == EXIT_SUCCESS ? "PASSED" : "FAILED");
cleanup_cgroup:
close(cgroup_fd);
cleanup_cgroup_env:
cleanup_cgroup_environment();
cleanup_obj:
return err;
}