Re: [PATCH bpf-next 2/2] selftests/bpf: Test that SO_REUSEPORT can be used with sk_assign helper

On 5/25/23 1:19 AM, Lorenz Bauer wrote:

diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c index a105c0cd008a..8a33bcea97de 100644 --- a/tools/testing/selftests/bpf/network_helpers.c +++ b/tools/testing/selftests/bpf/network_helpers.c @@ -423,6 +423,9 @@ struct nstoken *open_netns(const char *name) void close_netns(struct nstoken *token) {

• if (!token)

• return;
  

+1. :)

• ASSERT_OK(setns(token->orig_netns_fd, CLONE_NEWNET), "setns"); close(token->orig_netns_fd); free(token);

diff --git a/tools/testing/selftests/bpf/prog_tests/assign_reuse.c b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c new file mode 100644 index 000000000000..2cb9bb591e71 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/assign_reuse.c @@ -0,0 +1,280 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Isovalent */ +#include <uapi/linux/if_link.h> +#include <test_progs.h>

+#include <netinet/tcp.h> +#include <netinet/udp.h>

+#include "network_helpers.h" +#include "test_assign_reuse.skel.h"

+#define NS_TEST "assign_reuse" +#define LOOPBACK 1 +#define PORT 4443

+static int attach_reuseport(int sock_fd, int prog_fd) +{

• return setsockopt(sock_fd, SOL_SOCKET, SO_ATTACH_REUSEPORT_EBPF,

• 	  &prog_fd, sizeof(prog_fd));
  

+}

+static socklen_t inetaddr_len(const struct sockaddr_storage *addr) +{

• return addr->ss_family == AF_INET ? sizeof(struct sockaddr_in) :

•       addr->ss_family == AF_INET6 ? sizeof(struct sockaddr_in6) :
  

• 			     0;
  

+}

+static bool is_ipv6(const char *ip) +{

• return !!strchr(ip, ':');

+}

+static int make_socket(int sotype, const char *ip, int port,

•        struct sockaddr_storage *addr)
  

+{

• struct timeval timeo = { .tv_usec = 500000 /* 500 ms */ };
• int family = is_ipv6(ip) ? AF_INET6 : AF_INET;
• int ret, fd;
• ret = make_sockaddr(family, ip, port, addr, NULL);
• if (!ASSERT_OK(ret, "make_sockaddr"))

• return -1;
  

• fd = socket(addr->ss_family, sotype, 0);
• if (!ASSERT_GE(fd, 0, "socket"))

• return -1;
  

• ret = setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeo, sizeof(timeo));
• if (!ASSERT_OK(ret, "sndtimeo")) {

• close(fd);
  

• return -1;
  

• }
• ret = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeo, sizeof(timeo));
• if (!ASSERT_OK(ret, "rcvtimeo")) {

• close(fd);
  

• return -1;
  

• }
• return fd;

+}

+static int create_server(int sotype, const char *ip, int port, int prog_fd) +{

• struct sockaddr_storage addr = {};
• const int one = 1;
• int ret, fd;
• fd = make_socket(sotype, ip, port, &addr);
• if (fd < 0)

• return -1;
  

• if (sotype == SOCK_STREAM) {

• ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one,
  

• 		 sizeof(one));
  

• if (!ASSERT_OK(ret, "reuseaddr"))
  

• 	goto cleanup;
  

• }
• if (prog_fd >= 0) {

• ret = setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one,
  

• 		 sizeof(one));
  

• if (!ASSERT_OK(ret, "reuseport"))
  

• 	goto cleanup;
  

• ret = attach_reuseport(fd, prog_fd);
  

• if (!ASSERT_OK(ret, "attach_reuseport"))
  

• 	goto cleanup;
  

• }
• ret = bind(fd, (void *)&addr, inetaddr_len(&addr));
• if (!ASSERT_OK(ret, "bind"))

• goto cleanup;
  

• if (sotype == SOCK_STREAM) {

• ret = listen(fd, SOMAXCONN);
  

• if (!ASSERT_OK(ret, "listen"))
  

• 	goto cleanup;
  

• }
• return fd;

+cleanup:

• close(fd);
• return -1;

+}

+static int create_client(int sotype, const char *ip, int port) +{

• struct sockaddr_storage addr = {};
• int ret, fd;
• fd = make_socket(sotype, ip, port, &addr);
• if (fd < 0)

• return -1;
  

• ret = connect(fd, (void *)&addr, inetaddr_len(&addr));
• if (ret)

• goto cleanup;
  

• return fd;

+cleanup:

• close(fd);
• return -1;

+}

I believe a lot of the above can be done by start_reuseport_server() and connect_to_fd() from network_helpers.c.

[ ... ]

+void serial_test_assign_reuse(void)

Remove "serial_" .

+{

• struct nstoken *tok = NULL;
• SYS(out, "ip netns add %s", NS_TEST);
• SYS(cleanup, "ip -net %s link set dev lo up", NS_TEST);
• tok = open_netns(NS_TEST);
• if (!ASSERT_OK_PTR(tok, "netns token"))

• return;
  

• if (test__start_subtest("tcpv4"))

• run_assign_reuse(SOCK_STREAM, "127.0.0.1", PORT);
  

• if (test__start_subtest("tcpv6"))

• run_assign_reuse(SOCK_STREAM, "::1", PORT);
  

• if (test__start_subtest("udpv4"))

• run_assign_reuse(SOCK_DGRAM, "127.0.0.1", PORT);
  

• if (test__start_subtest("udpv6"))

• run_assign_reuse(SOCK_DGRAM, "::1", PORT);
  

+cleanup:

• close_netns(tok);
• SYS_NOFAIL("ip netns delete %s", NS_TEST);

+out:

• return;

+} diff --git a/tools/testing/selftests/bpf/progs/test_assign_reuse.c b/tools/testing/selftests/bpf/progs/test_assign_reuse.c new file mode 100644 index 000000000000..c83e870b2612 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_assign_reuse.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Isovalent */ +#include <stdbool.h> +#include <linux/bpf.h> +#include <linux/if_ether.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <bpf/bpf_endian.h> +#include <bpf/bpf_helpers.h> +#include <linux/pkt_cls.h>

+char LICENSE[] SEC("license") = "GPL";

+__u64 sk_cookie_seen; +__u64 reuseport_executed; +union {

• struct tcphdr tcp;
• struct udphdr udp;

+} headers;

+const volatile __u16 dest_port;

+struct {

• __uint(type, BPF_MAP_TYPE_SOCKMAP);
• __uint(max_entries, 1);
• __type(key, __u32);
• __type(value, __u64);

+} sk_map SEC(".maps");

+SEC("sk_reuseport") +int reuse_accept(struct sk_reuseport_md *ctx) +{

• reuseport_executed++;
• if (ctx->ip_protocol == IPPROTO_TCP) {

• if (ctx->data + sizeof(headers.tcp) > ctx->data_end)
  

• 	return SK_DROP;
  

• if (__builtin_memcmp(&headers.tcp, ctx->data, sizeof(headers.tcp)) != 0)
  

• 	return SK_DROP;
  

• } else if (ctx->ip_protocol == IPPROTO_UDP) {

• if (ctx->data + sizeof(headers.udp) > ctx->data_end)
  

• 	return SK_DROP;
  

• if (__builtin_memcmp(&headers.udp, ctx->data, sizeof(headers.udp)) != 0)
  

• 	return SK_DROP;
  

• } else {

• return SK_DROP;
  

• }
• sk_cookie_seen = bpf_get_socket_cookie(ctx->sk);
• return SK_PASS;

+}

+SEC("sk_reuseport") +int reuse_drop(struct sk_reuseport_md *ctx) +{

• reuseport_executed++;
• sk_cookie_seen = 0;
• return SK_DROP;

+}

+static inline int

nit. inline is no longer a must. Same for a few functions below.

+assign_sk(struct __sk_buff *skb) +{

• int zero = 0, ret = 0;
• struct bpf_sock *sk;
• sk = bpf_map_lookup_elem(&sk_map, &zero);
• if (!sk)

• return TC_ACT_SHOT;
  

• ret = bpf_sk_assign(skb, sk, 0);
• bpf_sk_release(sk);
• return ret ? TC_ACT_SHOT : TC_ACT_OK;

+}