> On Mar 28, 2023, at 11:35 AM, Stanislav Fomichev <sdf@xxxxxxxxxx> wrote: > > On Tue, Mar 28, 2023 at 10:51 AM Aditi Ghag <aditi.ghag@xxxxxxxxxxxxx> wrote: >> >> >> >>> On Mar 27, 2023, at 9:54 AM, Stanislav Fomichev <sdf@xxxxxxxxxx> wrote: >>> >>> On 03/27, Aditi Ghag wrote: >>> >>> >>>>> On Mar 24, 2023, at 2:52 PM, Stanislav Fomichev <sdf@xxxxxxxxxx> wrote: >>>>> >>>>> On 03/23, Aditi Ghag wrote: >>>>>> The test cases for destroying sockets mirror the intended usages of the >>>>>> bpf_sock_destroy kfunc using iterators. >>>>> >>>>>> The destroy helpers set `ECONNABORTED` error code that we can validate in >>>>>> the test code with client sockets. But UDP sockets have an overriding error >>>>>> code from the disconnect called during abort, so the error code the >>>>>> validation is only done for TCP sockets. >>>>> >>>>>> Signed-off-by: Aditi Ghag <aditi.ghag@xxxxxxxxxxxxx> >>>>>> --- >>>>>> .../selftests/bpf/prog_tests/sock_destroy.c | 195 ++++++++++++++++++ >>>>>> .../selftests/bpf/progs/sock_destroy_prog.c | 151 ++++++++++++++ >>>>>> 2 files changed, 346 insertions(+) >>>>>> create mode 100644 tools/testing/selftests/bpf/prog_tests/sock_destroy.c >>>>>> create mode 100644 tools/testing/selftests/bpf/progs/sock_destroy_prog.c >>>>> >>>>>> diff --git a/tools/testing/selftests/bpf/prog_tests/sock_destroy.c b/tools/testing/selftests/bpf/prog_tests/sock_destroy.c >>>>>> new file mode 100644 >>>>>> index 000000000000..cbce966af568 >>>>>> --- /dev/null >>>>>> +++ b/tools/testing/selftests/bpf/prog_tests/sock_destroy.c >>>>>> @@ -0,0 +1,195 @@ >>>>>> +// SPDX-License-Identifier: GPL-2.0 >>>>>> +#include <test_progs.h> >>>>>> + >>>>>> +#include "sock_destroy_prog.skel.h" >>>>>> +#include "network_helpers.h" >>>>>> + >>>>>> +#define SERVER_PORT 6062 >>>>>> + >>>>>> +static void start_iter_sockets(struct bpf_program *prog) >>>>>> +{ >>>>>> + struct bpf_link *link; >>>>>> + char buf[50] = {}; >>>>>> + int iter_fd, len; >>>>>> + >>>>>> + link = bpf_program__attach_iter(prog, NULL); >>>>>> + if (!ASSERT_OK_PTR(link, "attach_iter")) >>>>>> + return; >>>>>> + >>>>>> + iter_fd = bpf_iter_create(bpf_link__fd(link)); >>>>>> + if (!ASSERT_GE(iter_fd, 0, "create_iter")) >>>>>> + goto free_link; >>>>>> + >>>>>> + while ((len = read(iter_fd, buf, sizeof(buf))) > 0) >>>>>> + ; >>>>>> + ASSERT_GE(len, 0, "read"); >>>>>> + >>>>>> + close(iter_fd); >>>>>> + >>>>>> +free_link: >>>>>> + bpf_link__destroy(link); >>>>>> +} >>>>>> + >>>>>> +static void test_tcp_client(struct sock_destroy_prog *skel) >>>>>> +{ >>>>>> + int serv = -1, clien = -1, n = 0; >>>>>> + >>>>>> + serv = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0); >>>>>> + if (!ASSERT_GE(serv, 0, "start_server")) >>>>>> + goto cleanup_serv; >>>>>> + >>>>>> + clien = connect_to_fd(serv, 0); >>>>>> + if (!ASSERT_GE(clien, 0, "connect_to_fd")) >>>>>> + goto cleanup_serv; >>>>>> + >>>>>> + serv = accept(serv, NULL, NULL); >>>>>> + if (!ASSERT_GE(serv, 0, "serv accept")) >>>>>> + goto cleanup; >>>>>> + >>>>>> + n = send(clien, "t", 1, 0); >>>>>> + if (!ASSERT_GE(n, 0, "client send")) >>>>>> + goto cleanup; >>>>>> + >>>>>> + /* Run iterator program that destroys connected client sockets. */ >>>>>> + start_iter_sockets(skel->progs.iter_tcp6_client); >>>>>> + >>>>>> + n = send(clien, "t", 1, 0); >>>>>> + if (!ASSERT_LT(n, 0, "client_send on destroyed socket")) >>>>>> + goto cleanup; >>>>>> + ASSERT_EQ(errno, ECONNABORTED, "error code on destroyed socket"); >>>>>> + >>>>>> + >>>>>> +cleanup: >>>>>> + close(clien); >>>>>> +cleanup_serv: >>>>>> + close(serv); >>>>>> +} >>>>>> + >>>>>> +static void test_tcp_server(struct sock_destroy_prog *skel) >>>>>> +{ >>>>>> + int serv = -1, clien = -1, n = 0; >>>>>> + >>>>>> + serv = start_server(AF_INET6, SOCK_STREAM, NULL, SERVER_PORT, 0); >>>>>> + if (!ASSERT_GE(serv, 0, "start_server")) >>>>>> + goto cleanup_serv; >>>>>> + >>>>>> + clien = connect_to_fd(serv, 0); >>>>>> + if (!ASSERT_GE(clien, 0, "connect_to_fd")) >>>>>> + goto cleanup_serv; >>>>>> + >>>>>> + serv = accept(serv, NULL, NULL); >>>>>> + if (!ASSERT_GE(serv, 0, "serv accept")) >>>>>> + goto cleanup; >>>>>> + >>>>>> + n = send(clien, "t", 1, 0); >>>>>> + if (!ASSERT_GE(n, 0, "client send")) >>>>>> + goto cleanup; >>>>>> + >>>>>> + /* Run iterator program that destroys server sockets. */ >>>>>> + start_iter_sockets(skel->progs.iter_tcp6_server); >>>>>> + >>>>>> + n = send(clien, "t", 1, 0); >>>>>> + if (!ASSERT_LT(n, 0, "client_send on destroyed socket")) >>>>>> + goto cleanup; >>>>>> + ASSERT_EQ(errno, ECONNRESET, "error code on destroyed socket"); >>>>>> + >>>>>> + >>>>>> +cleanup: >>>>>> + close(clien); >>>>>> +cleanup_serv: >>>>>> + close(serv); >>>>>> +} >>>>>> + >>>>>> + >>>>>> +static void test_udp_client(struct sock_destroy_prog *skel) >>>>>> +{ >>>>>> + int serv = -1, clien = -1, n = 0; >>>>>> + >>>>>> + serv = start_server(AF_INET6, SOCK_DGRAM, NULL, 6161, 0); >>>>>> + if (!ASSERT_GE(serv, 0, "start_server")) >>>>>> + goto cleanup_serv; >>>>>> + >>>>>> + clien = connect_to_fd(serv, 0); >>>>>> + if (!ASSERT_GE(clien, 0, "connect_to_fd")) >>>>>> + goto cleanup_serv; >>>>>> + >>>>>> + n = send(clien, "t", 1, 0); >>>>>> + if (!ASSERT_GE(n, 0, "client send")) >>>>>> + goto cleanup; >>>>>> + >>>>>> + /* Run iterator program that destroys sockets. */ >>>>>> + start_iter_sockets(skel->progs.iter_udp6_client); >>>>>> + >>>>>> + n = send(clien, "t", 1, 0); >>>>>> + if (!ASSERT_LT(n, 0, "client_send on destroyed socket")) >>>>>> + goto cleanup; >>>>>> + /* UDP sockets have an overriding error code after they are disconnected, >>>>>> + * so we don't check for ECONNABORTED error code. >>>>>> + */ >>>>>> + >>>>>> +cleanup: >>>>>> + close(clien); >>>>>> +cleanup_serv: >>>>>> + close(serv); >>>>>> +} >>>>>> + >>>>>> +static void test_udp_server(struct sock_destroy_prog *skel) >>>>>> +{ >>>>>> + int *listen_fds = NULL, n, i; >>>>>> + unsigned int num_listens = 5; >>>>>> + char buf[1]; >>>>>> + >>>>>> + /* Start reuseport servers. */ >>>>>> + listen_fds = start_reuseport_server(AF_INET6, SOCK_DGRAM, >>>>>> + "::1", SERVER_PORT, 0, >>>>>> + num_listens); >>>>>> + if (!ASSERT_OK_PTR(listen_fds, "start_reuseport_server")) >>>>>> + goto cleanup; >>>>>> + >>>>>> + /* Run iterator program that destroys server sockets. */ >>>>>> + start_iter_sockets(skel->progs.iter_udp6_server); >>>>>> + >>>>>> + for (i = 0; i < num_listens; ++i) { >>>>>> + n = read(listen_fds[i], buf, sizeof(buf)); >>>>>> + if (!ASSERT_EQ(n, -1, "read") || >>>>>> + !ASSERT_EQ(errno, ECONNABORTED, "error code on destroyed socket")) >>>>>> + break; >>>>>> + } >>>>>> + ASSERT_EQ(i, num_listens, "server socket"); >>>>>> + >>>>>> +cleanup: >>>>>> + free_fds(listen_fds, num_listens); >>>>>> +} >>>>>> + >>>>>> +void test_sock_destroy(void) >>>>>> +{ >>>>>> + int cgroup_fd = 0; >>>>>> + struct sock_destroy_prog *skel; >>>>>> + >>>>>> + skel = sock_destroy_prog__open_and_load(); >>>>>> + if (!ASSERT_OK_PTR(skel, "skel_open")) >>>>>> + return; >>>>>> + >>>>>> + cgroup_fd = test__join_cgroup("/sock_destroy"); >>>>>> + if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup")) >>>>>> + goto close_cgroup_fd; >>>>>> + >>>>>> + skel->links.sock_connect = bpf_program__attach_cgroup( >>>>>> + skel->progs.sock_connect, cgroup_fd); >>>>>> + if (!ASSERT_OK_PTR(skel->links.sock_connect, "prog_attach")) >>>>>> + goto close_cgroup_fd; >>>>>> + >>>>>> + if (test__start_subtest("tcp_client")) >>>>>> + test_tcp_client(skel); >>>>>> + if (test__start_subtest("tcp_server")) >>>>>> + test_tcp_server(skel); >>>>>> + if (test__start_subtest("udp_client")) >>>>>> + test_udp_client(skel); >>>>>> + if (test__start_subtest("udp_server")) >>>>>> + test_udp_server(skel); >>>>>> + >>>>>> + >>>>>> +close_cgroup_fd: >>>>>> + close(cgroup_fd); >>>>>> + sock_destroy_prog__destroy(skel); >>>>>> +} >>>>>> diff --git a/tools/testing/selftests/bpf/progs/sock_destroy_prog.c b/tools/testing/selftests/bpf/progs/sock_destroy_prog.c >>>>>> new file mode 100644 >>>>>> index 000000000000..8e09d82c50f3 >>>>>> --- /dev/null >>>>>> +++ b/tools/testing/selftests/bpf/progs/sock_destroy_prog.c >>>>>> @@ -0,0 +1,151 @@ >>>>>> +// SPDX-License-Identifier: GPL-2.0 >>>>>> + >>>>>> +#include "vmlinux.h" >>>>>> + >>>>>> +#include "bpf_tracing_net.h" >>>>>> +#include <bpf/bpf_helpers.h> >>>>>> +#include <bpf/bpf_endian.h> >>>>>> + >>>>>> +#define AF_INET6 10 >>>>> >>>>> [..] >>>>> >>>>>> +/* Keep it in sync with prog_test/sock_destroy. */ >>>>>> +#define SERVER_PORT 6062 >>>>> >>>>> The test looks good, one optional unrelated nit maybe: >>>>> >>>>> I've been guilty of these hard-coded ports in the past, but maybe >>>>> we should stop hard-coding them? Getting the address of the listener (bound to >>>>> port 0) and passing it to the bpf program via global variable should be super >>>>> easy now (with the skeletons and network_helpers). >>> >>> >>>> I briefly considered adding the ports in a map, and retrieving them in the test. But it didn't seem worthwhile as the tests should fail clearly when there is a mismatch. >>> >>> My worry is that the amount of those tests that have a hard-coded port >>> grows and at some point somebody will clash with somebody else. >>> And it might not be 100% apparent because test_progs is now multi-threaded >>> and racy.. >>> >> >> So you would like the ports to be unique across all the tests. > > Yeah, but it's hard without having some kind of global registry. Take > a look at the following: > > $ grep -Iri _port tools/testing/selftests/bpf/ | grep -P '\d{4}' > > tools/testing/selftests/bpf/progs/connect_force_port4.c: > sa.sin_port = bpf_htons(22222); > tools/testing/selftests/bpf/progs/connect_force_port4.c: if > (ctx->user_port == bpf_htons(60000)) { > tools/testing/selftests/bpf/progs/connect_force_port4.c: > ctx->user_port = bpf_htons(60123); > tools/testing/selftests/bpf/progs/connect_force_port4.c: if > (ctx->user_port == bpf_htons(60123)) { > tools/testing/selftests/bpf/progs/connect_force_port4.c: > ctx->user_port = bpf_htons(60000); > tools/testing/selftests/bpf/progs/connect_force_port4.c: if > (ctx->user_port == bpf_htons(60123)) { > tools/testing/selftests/bpf/progs/connect6_prog.c:#define > DST_REWRITE_PORT6 6666 > tools/testing/selftests/bpf/progs/test_sk_lookup.c:static const __u16 > SRC_PORT = bpf_htons(8008); > tools/testing/selftests/bpf/progs/test_sk_lookup.c:static const __u16 > DST_PORT = 7007; /* Host byte order */ > tools/testing/selftests/bpf/progs/test_tc_dtime.c: __u16 > dst_ns_port = __bpf_htons(50000 + test); > tools/testing/selftests/bpf/progs/connect4_dropper.c: if > (ctx->user_port == bpf_htons(60120)) > tools/testing/selftests/bpf/progs/connect_force_port6.c: > sa.sin6_port = bpf_htons(22223); > tools/testing/selftests/bpf/progs/connect_force_port6.c: if > (ctx->user_port == bpf_htons(60000)) { > tools/testing/selftests/bpf/progs/connect_force_port6.c: > ctx->user_port = bpf_htons(60124); > tools/testing/selftests/bpf/progs/connect_force_port6.c: if > (ctx->user_port == bpf_htons(60124)) { > tools/testing/selftests/bpf/progs/connect_force_port6.c: > ctx->user_port = bpf_htons(60000); > tools/testing/selftests/bpf/progs/connect_force_port6.c: if > (ctx->user_port == bpf_htons(60124)) { > tools/testing/selftests/bpf/progs/test_tunnel_kern.c:#define > VXLAN_UDP_PORT 4789 > tools/testing/selftests/bpf/progs/sendmsg4_prog.c:#define DST_PORT > 4040 > tools/testing/selftests/bpf/progs/sendmsg4_prog.c:#define > DST_REWRITE_PORT4 4444 > tools/testing/selftests/bpf/progs/connect4_prog.c:#define > DST_REWRITE_PORT4 4444 > tools/testing/selftests/bpf/progs/bind6_prog.c:#define SERV6_PORT > 6060 > tools/testing/selftests/bpf/progs/bind6_prog.c:#define > SERV6_REWRITE_PORT 6666 > tools/testing/selftests/bpf/progs/sendmsg6_prog.c:#define > DST_REWRITE_PORT6 6666 > tools/testing/selftests/bpf/progs/recvmsg4_prog.c:#define SERV4_PORT > 4040 > <cut> > > .... there is much more ... > >>> Getting the address of the listener (bound to >>> port 0) and passing it to the bpf program via global variable should be super >>> easy now (with the skeletons and network_helpers). >> >> Just so that we are on the same page, could you point to which network helpers are you referring to here for passing global variables? > > Take a look at the following existing tests: > * prog_tests/cgroup_skb_sk_lookup.c > * run_lookup_test(&skel->bss->g_serv_port, out_sk); > * progs/cgroup_skb_sk_lookup_kern.c > * g_serv_port > > Fundamentally, here is what's preferable to have: > > fd = start_server(..., port=0, ...); > listener_port = get_port(fd); /* new network_helpers.h helper that > calls getsockname */ > obj->bss->port = listener_port; /* populate the port in the BPF program */ > > Does it make sense? That makes sense. Good to know for future references. The client tests don't have hard-coded ports anyway, only the server tests do as they are using the so_resuseport option. You did mention that this was an optional nit, so I'll leave the hard-coded ports for the server tests for now. Hope that's reasonable. > >>>>> >>>>> And, unrelated, maybe also fix a bunch of places where the reverse christmas >>>>> tree doesn't look reverse anymore? >>> >>>> Ok. The checks should be part of tooling (e.g., checkpatch) though if they are meant to be enforced consistently, no? >>> >>> They are networking specific, so they are not part of a checkpath :-( >>> I won't say they are consistently enforced, but we try to keep then >>> whenever possible. >>> >>>>> >>>>>> + >>>>>> +int bpf_sock_destroy(struct sock_common *sk) __ksym; >>>>>> + >>>>>> +struct { >>>>>> + __uint(type, BPF_MAP_TYPE_ARRAY); >>>>>> + __uint(max_entries, 1); >>>>>> + __type(key, __u32); >>>>>> + __type(value, __u64); >>>>>> +} tcp_conn_sockets SEC(".maps"); >>>>>> + >>>>>> +struct { >>>>>> + __uint(type, BPF_MAP_TYPE_ARRAY); >>>>>> + __uint(max_entries, 1); >>>>>> + __type(key, __u32); >>>>>> + __type(value, __u64); >>>>>> +} udp_conn_sockets SEC(".maps"); >>>>>> + >>>>>> +SEC("cgroup/connect6") >>>>>> +int sock_connect(struct bpf_sock_addr *ctx) >>>>>> +{ >>>>>> + int key = 0; >>>>>> + __u64 sock_cookie = 0; >>>>>> + __u32 keyc = 0; >>>>>> + >>>>>> + if (ctx->family != AF_INET6 || ctx->user_family != AF_INET6) >>>>>> + return 1; >>>>>> + >>>>>> + sock_cookie = bpf_get_socket_cookie(ctx); >>>>>> + if (ctx->protocol == IPPROTO_TCP) >>>>>> + bpf_map_update_elem(&tcp_conn_sockets, &key, &sock_cookie, 0); >>>>>> + else if (ctx->protocol == IPPROTO_UDP) >>>>>> + bpf_map_update_elem(&udp_conn_sockets, &keyc, &sock_cookie, 0); >>>>>> + else >>>>>> + return 1; >>>>>> + >>>>>> + return 1; >>>>>> +} >>>>>> + >>>>>> +SEC("iter/tcp") >>>>>> +int iter_tcp6_client(struct bpf_iter__tcp *ctx) >>>>>> +{ >>>>>> + struct sock_common *sk_common = ctx->sk_common; >>>>>> + struct seq_file *seq = ctx->meta->seq; >>>>>> + __u64 sock_cookie = 0; >>>>>> + __u64 *val; >>>>>> + int key = 0; >>>>>> + >>>>>> + if (!sk_common) >>>>>> + return 0; >>>>>> + >>>>>> + if (sk_common->skc_family != AF_INET6) >>>>>> + return 0; >>>>>> + >>>>>> + sock_cookie = bpf_get_socket_cookie(sk_common); >>>>>> + val = bpf_map_lookup_elem(&tcp_conn_sockets, &key); >>>>>> + if (!val) >>>>>> + return 0; >>>>>> + /* Destroy connected client sockets. */ >>>>>> + if (sock_cookie == *val) >>>>>> + bpf_sock_destroy(sk_common); >>>>>> + >>>>>> + return 0; >>>>>> +} >>>>>> + >>>>>> +SEC("iter/tcp") >>>>>> +int iter_tcp6_server(struct bpf_iter__tcp *ctx) >>>>>> +{ >>>>>> + struct sock_common *sk_common = ctx->sk_common; >>>>>> + struct seq_file *seq = ctx->meta->seq; >>>>>> + struct tcp6_sock *tcp_sk; >>>>>> + const struct inet_connection_sock *icsk; >>>>>> + const struct inet_sock *inet; >>>>>> + __u16 srcp; >>>>>> + >>>>>> + if (!sk_common) >>>>>> + return 0; >>>>>> + >>>>>> + if (sk_common->skc_family != AF_INET6) >>>>>> + return 0; >>>>>> + >>>>>> + tcp_sk = bpf_skc_to_tcp6_sock(sk_common); >>>>>> + if (!tcp_sk) >>>>>> + return 0; >>>>>> + >>>>>> + icsk = &tcp_sk->tcp.inet_conn; >>>>>> + inet = &icsk->icsk_inet; >>>>>> + srcp = bpf_ntohs(inet->inet_sport); >>>>>> + >>>>>> + /* Destroy server sockets. */ >>>>>> + if (srcp == SERVER_PORT) >>>>>> + bpf_sock_destroy(sk_common); >>>>>> + >>>>>> + return 0; >>>>>> +} >>>>>> + >>>>>> + >>>>>> +SEC("iter/udp") >>>>>> +int iter_udp6_client(struct bpf_iter__udp *ctx) >>>>>> +{ >>>>>> + struct seq_file *seq = ctx->meta->seq; >>>>>> + struct udp_sock *udp_sk = ctx->udp_sk; >>>>>> + struct sock *sk = (struct sock *) udp_sk; >>>>>> + __u64 sock_cookie = 0, *val; >>>>>> + int key = 0; >>>>>> + >>>>>> + if (!sk) >>>>>> + return 0; >>>>>> + >>>>>> + sock_cookie = bpf_get_socket_cookie(sk); >>>>>> + val = bpf_map_lookup_elem(&udp_conn_sockets, &key); >>>>>> + if (!val) >>>>>> + return 0; >>>>>> + /* Destroy connected client sockets. */ >>>>>> + if (sock_cookie == *val) >>>>>> + bpf_sock_destroy((struct sock_common *)sk); >>>>>> + >>>>>> + return 0; >>>>>> +} >>>>>> + >>>>>> +SEC("iter/udp") >>>>>> +int iter_udp6_server(struct bpf_iter__udp *ctx) >>>>>> +{ >>>>>> + struct seq_file *seq = ctx->meta->seq; >>>>>> + struct udp_sock *udp_sk = ctx->udp_sk; >>>>>> + struct sock *sk = (struct sock *) udp_sk; >>>>>> + __u16 srcp; >>>>>> + struct inet_sock *inet; >>>>>> + >>>>>> + if (!sk) >>>>>> + return 0; >>>>>> + >>>>>> + inet = &udp_sk->inet; >>>>>> + srcp = bpf_ntohs(inet->inet_sport); >>>>>> + if (srcp == SERVER_PORT) >>>>>> + bpf_sock_destroy((struct sock_common *)sk); >>>>>> + >>>>>> + return 0; >>>>>> +} >>>>>> + >>>>>> +char _license[] SEC("license") = "GPL"; >>>>>> -- >>>>>> 2.34.1