From: Daniel Borkmann <daniel@iogearbox.net>
Date: Tue, 19 May 2020 00:45:48 +0200
Subject: bpf, testing: Add get{peer, sock}name selftests to test_progs
Patch-mainline: v5.8-rc1
Git-commit: 566fc3f5d1c641b510ec487cf274a047f8a1e849
References: bsc#1177028
Extend the existing connect_force_port test to assert get{peer,sock}name programs
as well. The workflow for e.g. IPv4 is as follows: i) server binds to concrete
port, ii) client calls getsockname() on server fd which exposes 1.2.3.4:60000 to
client, iii) client connects to service address 1.2.3.4:60000 binds to concrete
local address (127.0.0.1:22222) and remaps service address to a concrete backend
address (127.0.0.1:60123), iv) client then calls getsockname() on its own fd to
verify local address (127.0.0.1:22222) and getpeername() on its own fd which then
publishes service address (1.2.3.4:60000) instead of actual backend. Same workflow
is done for IPv6 just with different address/port tuples.
# ./test_progs -t connect_force_port
#14 connect_force_port:OK
Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/3343da6ad08df81af715a95d61a84fb4a960f2bf.1589841594.git.daniel@iogearbox.net
Acked-by: Gary Lin <glin@suse.com>
---
tools/testing/selftests/bpf/network_helpers.c | 11 +
tools/testing/selftests/bpf/network_helpers.h | 1
tools/testing/selftests/bpf/prog_tests/connect_force_port.c | 107 ++++++++----
tools/testing/selftests/bpf/progs/connect_force_port4.c | 59 ++++++
tools/testing/selftests/bpf/progs/connect_force_port6.c | 70 +++++++
5 files changed, 215 insertions(+), 33 deletions(-)
--- a/tools/testing/selftests/bpf/network_helpers.c
+++ b/tools/testing/selftests/bpf/network_helpers.c
@@ -5,6 +5,8 @@
#include <string.h>
#include <unistd.h>
+#include <arpa/inet.h>
+
#include <sys/epoll.h>
#include <linux/err.h>
@@ -35,7 +37,7 @@ struct ipv6_packet pkt_v6 = {
.tcp.doff = 5,
};
-int start_server(int family, int type)
+int start_server_with_port(int family, int type, __u16 port)
{
struct sockaddr_storage addr = {};
socklen_t len;
@@ -45,11 +47,13 @@ int start_server(int family, int type)
struct sockaddr_in *sin = (void *)&addr;
sin->sin_family = AF_INET;
+ sin->sin_port = htons(port);
len = sizeof(*sin);
} else {
struct sockaddr_in6 *sin6 = (void *)&addr;
sin6->sin6_family = AF_INET6;
+ sin6->sin6_port = htons(port);
len = sizeof(*sin6);
}
@@ -76,6 +80,11 @@ int start_server(int family, int type)
return fd;
}
+int start_server(int family, int type)
+{
+ return start_server_with_port(family, type, 0);
+}
+
static const struct timeval timeo_sec = { .tv_sec = 3 };
static const size_t timeo_optlen = sizeof(timeo_sec);
--- a/tools/testing/selftests/bpf/network_helpers.h
+++ b/tools/testing/selftests/bpf/network_helpers.h
@@ -34,6 +34,7 @@ struct ipv6_packet {
extern struct ipv6_packet pkt_v6;
int start_server(int family, int type);
+int start_server_with_port(int family, int type, __u16 port);
int connect_to_fd(int family, int type, int server_fd);
int connect_fd_to_fd(int client_fd, int server_fd);
int connect_wait(int client_fd);
--- a/tools/testing/selftests/bpf/prog_tests/connect_force_port.c
+++ b/tools/testing/selftests/bpf/prog_tests/connect_force_port.c
@@ -4,7 +4,8 @@
#include "cgroup_helpers.h"
#include "network_helpers.h"
-static int verify_port(int family, int fd, int expected)
+static int verify_ports(int family, int fd,
+ __u16 expected_local, __u16 expected_peer)
{
struct sockaddr_storage addr;
socklen_t len = sizeof(addr);
@@ -20,9 +21,25 @@ static int verify_port(int family, int f
else
port = ((struct sockaddr_in6 *)&addr)->sin6_port;
- if (ntohs(port) != expected) {
- log_err("Unexpected port %d, expected %d", ntohs(port),
- expected);
+ if (ntohs(port) != expected_local) {
+ log_err("Unexpected local port %d, expected %d", ntohs(port),
+ expected_local);
+ return -1;
+ }
+
+ if (getpeername(fd, (struct sockaddr *)&addr, &len)) {
+ log_err("Failed to get peer addr");
+ return -1;
+ }
+
+ if (family == AF_INET)
+ port = ((struct sockaddr_in *)&addr)->sin_port;
+ else
+ port = ((struct sockaddr_in6 *)&addr)->sin6_port;
+
+ if (ntohs(port) != expected_peer) {
+ log_err("Unexpected peer port %d, expected %d", ntohs(port),
+ expected_peer);
return -1;
}
@@ -31,33 +48,67 @@ static int verify_port(int family, int f
static int run_test(int cgroup_fd, int server_fd, int family, int type)
{
+ bool v4 = family == AF_INET;
+ __u16 expected_local_port = v4 ? 22222 : 22223;
+ __u16 expected_peer_port = 60000;
struct bpf_prog_load_attr attr = {
- .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
+ .file = v4 ? "./connect_force_port4.o" :
+ "./connect_force_port6.o",
};
+ struct bpf_program *prog;
struct bpf_object *obj;
- int expected_port;
- int prog_fd;
- int err;
- int fd;
-
- if (family == AF_INET) {
- attr.file = "./connect_force_port4.o";
- attr.expected_attach_type = BPF_CGROUP_INET4_CONNECT;
- expected_port = 22222;
- } else {
- attr.file = "./connect_force_port6.o";
- attr.expected_attach_type = BPF_CGROUP_INET6_CONNECT;
- expected_port = 22223;
- }
+ int xlate_fd, fd, err;
+ __u32 duration = 0;
- err = bpf_prog_load_xattr(&attr, &obj, &prog_fd);
+ err = bpf_prog_load_xattr(&attr, &obj, &xlate_fd);
if (err) {
log_err("Failed to load BPF object");
return -1;
}
- err = bpf_prog_attach(prog_fd, cgroup_fd, attr.expected_attach_type,
- 0);
+ prog = bpf_object__find_program_by_title(obj, v4 ?
+ "cgroup/connect4" :
+ "cgroup/connect6");
+ if (CHECK(!prog, "find_prog", "connect prog not found\n")) {
+ err = -EIO;
+ goto close_bpf_object;
+ }
+
+ err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd, v4 ?
+ BPF_CGROUP_INET4_CONNECT :
+ BPF_CGROUP_INET6_CONNECT, 0);
+ if (err) {
+ log_err("Failed to attach BPF program");
+ goto close_bpf_object;
+ }
+
+ prog = bpf_object__find_program_by_title(obj, v4 ?
+ "cgroup/getpeername4" :
+ "cgroup/getpeername6");
+ if (CHECK(!prog, "find_prog", "getpeername prog not found\n")) {
+ err = -EIO;
+ goto close_bpf_object;
+ }
+
+ err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd, v4 ?
+ BPF_CGROUP_INET4_GETPEERNAME :
+ BPF_CGROUP_INET6_GETPEERNAME, 0);
+ if (err) {
+ log_err("Failed to attach BPF program");
+ goto close_bpf_object;
+ }
+
+ prog = bpf_object__find_program_by_title(obj, v4 ?
+ "cgroup/getsockname4" :
+ "cgroup/getsockname6");
+ if (CHECK(!prog, "find_prog", "getsockname prog not found\n")) {
+ err = -EIO;
+ goto close_bpf_object;
+ }
+
+ err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd, v4 ?
+ BPF_CGROUP_INET4_GETSOCKNAME :
+ BPF_CGROUP_INET6_GETSOCKNAME, 0);
if (err) {
log_err("Failed to attach BPF program");
goto close_bpf_object;
@@ -69,8 +120,8 @@ static int run_test(int cgroup_fd, int s
goto close_bpf_object;
}
- err = verify_port(family, fd, expected_port);
-
+ err = verify_ports(family, fd, expected_local_port,
+ expected_peer_port);
close(fd);
close_bpf_object:
@@ -86,25 +137,25 @@ void test_connect_force_port(void)
if (CHECK_FAIL(cgroup_fd < 0))
return;
- server_fd = start_server(AF_INET, SOCK_STREAM);
+ server_fd = start_server_with_port(AF_INET, SOCK_STREAM, 60123);
if (CHECK_FAIL(server_fd < 0))
goto close_cgroup_fd;
CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET, SOCK_STREAM));
close(server_fd);
- server_fd = start_server(AF_INET6, SOCK_STREAM);
+ server_fd = start_server_with_port(AF_INET6, SOCK_STREAM, 60124);
if (CHECK_FAIL(server_fd < 0))
goto close_cgroup_fd;
CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET6, SOCK_STREAM));
close(server_fd);
- server_fd = start_server(AF_INET, SOCK_DGRAM);
+ server_fd = start_server_with_port(AF_INET, SOCK_DGRAM, 60123);
if (CHECK_FAIL(server_fd < 0))
goto close_cgroup_fd;
CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET, SOCK_DGRAM));
close(server_fd);
- server_fd = start_server(AF_INET6, SOCK_DGRAM);
+ server_fd = start_server_with_port(AF_INET6, SOCK_DGRAM, 60124);
if (CHECK_FAIL(server_fd < 0))
goto close_cgroup_fd;
CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET6, SOCK_DGRAM));
--- a/tools/testing/selftests/bpf/progs/connect_force_port4.c
+++ b/tools/testing/selftests/bpf/progs/connect_force_port4.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
#include <string.h>
+#include <stdbool.h>
#include <linux/bpf.h>
#include <linux/in.h>
@@ -12,17 +13,71 @@
char _license[] SEC("license") = "GPL";
int _version SEC("version") = 1;
+struct svc_addr {
+ __be32 addr;
+ __be16 port;
+};
+
+struct {
+ __uint(type, BPF_MAP_TYPE_SK_STORAGE);
+ __uint(map_flags, BPF_F_NO_PREALLOC);
+ __type(key, int);
+ __type(value, struct svc_addr);
+} service_mapping SEC(".maps");
+
SEC("cgroup/connect4")
-int _connect4(struct bpf_sock_addr *ctx)
+int connect4(struct bpf_sock_addr *ctx)
{
struct sockaddr_in sa = {};
+ struct svc_addr *orig;
+ /* Force local address to 127.0.0.1:22222. */
sa.sin_family = AF_INET;
sa.sin_port = bpf_htons(22222);
- sa.sin_addr.s_addr = bpf_htonl(0x7f000001); /* 127.0.0.1 */
+ sa.sin_addr.s_addr = bpf_htonl(0x7f000001);
if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0)
return 0;
+ /* Rewire service 1.2.3.4:60000 to backend 127.0.0.1:60123. */
+ if (ctx->user_port == bpf_htons(60000)) {
+ orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0,
+ BPF_SK_STORAGE_GET_F_CREATE);
+ if (!orig)
+ return 0;
+
+ orig->addr = ctx->user_ip4;
+ orig->port = ctx->user_port;
+
+ ctx->user_ip4 = bpf_htonl(0x7f000001);
+ ctx->user_port = bpf_htons(60123);
+ }
+ return 1;
+}
+
+SEC("cgroup/getsockname4")
+int getsockname4(struct bpf_sock_addr *ctx)
+{
+ /* Expose local server as 1.2.3.4:60000 to client. */
+ if (ctx->user_port == bpf_htons(60123)) {
+ ctx->user_ip4 = bpf_htonl(0x01020304);
+ ctx->user_port = bpf_htons(60000);
+ }
+ return 1;
+}
+
+SEC("cgroup/getpeername4")
+int getpeername4(struct bpf_sock_addr *ctx)
+{
+ struct svc_addr *orig;
+
+ /* Expose service 1.2.3.4:60000 as peer instead of backend. */
+ if (ctx->user_port == bpf_htons(60123)) {
+ orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0, 0);
+ if (orig) {
+ ctx->user_ip4 = orig->addr;
+ ctx->user_port = orig->port;
+ }
+ }
return 1;
}
--- a/tools/testing/selftests/bpf/progs/connect_force_port6.c
+++ b/tools/testing/selftests/bpf/progs/connect_force_port6.c
@@ -12,17 +12,83 @@
char _license[] SEC("license") = "GPL";
int _version SEC("version") = 1;
+struct svc_addr {
+ __be32 addr[4];
+ __be16 port;
+};
+
+struct {
+ __uint(type, BPF_MAP_TYPE_SK_STORAGE);
+ __uint(map_flags, BPF_F_NO_PREALLOC);
+ __type(key, int);
+ __type(value, struct svc_addr);
+} service_mapping SEC(".maps");
+
SEC("cgroup/connect6")
-int _connect6(struct bpf_sock_addr *ctx)
+int connect6(struct bpf_sock_addr *ctx)
{
struct sockaddr_in6 sa = {};
+ struct svc_addr *orig;
+ /* Force local address to [::1]:22223. */
sa.sin6_family = AF_INET6;
sa.sin6_port = bpf_htons(22223);
- sa.sin6_addr.s6_addr32[3] = bpf_htonl(1); /* ::1 */
+ sa.sin6_addr.s6_addr32[3] = bpf_htonl(1);
if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0)
return 0;
+ /* Rewire service [fc00::1]:60000 to backend [::1]:60124. */
+ if (ctx->user_port == bpf_htons(60000)) {
+ orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0,
+ BPF_SK_STORAGE_GET_F_CREATE);
+ if (!orig)
+ return 0;
+
+ orig->addr[0] = ctx->user_ip6[0];
+ orig->addr[1] = ctx->user_ip6[1];
+ orig->addr[2] = ctx->user_ip6[2];
+ orig->addr[3] = ctx->user_ip6[3];
+ orig->port = ctx->user_port;
+
+ ctx->user_ip6[0] = 0;
+ ctx->user_ip6[1] = 0;
+ ctx->user_ip6[2] = 0;
+ ctx->user_ip6[3] = bpf_htonl(1);
+ ctx->user_port = bpf_htons(60124);
+ }
+ return 1;
+}
+
+SEC("cgroup/getsockname6")
+int getsockname6(struct bpf_sock_addr *ctx)
+{
+ /* Expose local server as [fc00::1]:60000 to client. */
+ if (ctx->user_port == bpf_htons(60124)) {
+ ctx->user_ip6[0] = bpf_htonl(0xfc000000);
+ ctx->user_ip6[1] = 0;
+ ctx->user_ip6[2] = 0;
+ ctx->user_ip6[3] = bpf_htonl(1);
+ ctx->user_port = bpf_htons(60000);
+ }
+ return 1;
+}
+
+SEC("cgroup/getpeername6")
+int getpeername6(struct bpf_sock_addr *ctx)
+{
+ struct svc_addr *orig;
+
+ /* Expose service [fc00::1]:60000 as peer instead of backend. */
+ if (ctx->user_port == bpf_htons(60124)) {
+ orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0, 0);
+ if (orig) {
+ ctx->user_ip6[0] = orig->addr[0];
+ ctx->user_ip6[1] = orig->addr[1];
+ ctx->user_ip6[2] = orig->addr[2];
+ ctx->user_ip6[3] = orig->addr[3];
+ ctx->user_port = orig->port;
+ }
+ }
return 1;
}