// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include <bpf/bpf_endian.h>

#include "sock_destroy_prog.skel.h"
#include "sock_destroy_prog_fail.skel.h"
#include "network_helpers.h"

#define TEST_NS "sock_destroy_netns"

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, accept_serv = -1, n;

        serv = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
        if (!ASSERT_GE(serv, 0, "start_server"))
                goto cleanup;

        clien = connect_to_fd(serv, 0);
        if (!ASSERT_GE(clien, 0, "connect_to_fd"))
                goto cleanup;

        accept_serv = accept(serv, NULL, NULL);
        if (!ASSERT_GE(accept_serv, 0, "serv accept"))
                goto cleanup;

        n = send(clien, "t", 1, 0);
        if (!ASSERT_EQ(n, 1, "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:
        if (clien != -1)
                close(clien);
        if (accept_serv != -1)
                close(accept_serv);
        if (serv != -1)
                close(serv);
}

static void test_tcp_server(struct sock_destroy_prog *skel)
{
        int serv = -1, clien = -1, accept_serv = -1, n, serv_port;

        serv = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
        if (!ASSERT_GE(serv, 0, "start_server"))
                goto cleanup;
        serv_port = get_socket_local_port(serv);
        if (!ASSERT_GE(serv_port, 0, "get_sock_local_port"))
                goto cleanup;
        skel->bss->serv_port = (__be16) serv_port;

        clien = connect_to_fd(serv, 0);
        if (!ASSERT_GE(clien, 0, "connect_to_fd"))
                goto cleanup;

        accept_serv = accept(serv, NULL, NULL);
        if (!ASSERT_GE(accept_serv, 0, "serv accept"))
                goto cleanup;

        n = send(clien, "t", 1, 0);
        if (!ASSERT_EQ(n, 1, "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:
        if (clien != -1)
                close(clien);
        if (accept_serv != -1)
                close(accept_serv);
        if (serv != -1)
                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, 0, 0);
        if (!ASSERT_GE(serv, 0, "start_server"))
                goto cleanup;

        clien = connect_to_fd(serv, 0);
        if (!ASSERT_GE(clien, 0, "connect_to_fd"))
                goto cleanup;

        n = send(clien, "t", 1, 0);
        if (!ASSERT_EQ(n, 1, "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:
        if (clien != -1)
                close(clien);
        if (serv != -1)
                close(serv);
}

static void test_udp_server(struct sock_destroy_prog *skel)
{
        int *listen_fds = NULL, n, i, serv_port;
        unsigned int num_listens = 5;
        char buf[1];

        /* Start reuseport servers. */
        listen_fds = start_reuseport_server(AF_INET6, SOCK_DGRAM,
                                            "::1", 0, 0, num_listens);
        if (!ASSERT_OK_PTR(listen_fds, "start_reuseport_server"))
                goto cleanup;
        serv_port = get_socket_local_port(listen_fds[0]);
        if (!ASSERT_GE(serv_port, 0, "get_sock_local_port"))
                goto cleanup;
        skel->bss->serv_port = (__be16) serv_port;

        /* 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)
{
        struct sock_destroy_prog *skel;
        struct nstoken *nstoken = NULL;
        int cgroup_fd;

        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 cleanup;

        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 cleanup;

        SYS(cleanup, "ip netns add %s", TEST_NS);
        SYS(cleanup, "ip -net %s link set dev lo up", TEST_NS);

        nstoken = open_netns(TEST_NS);
        if (!ASSERT_OK_PTR(nstoken, "open_netns"))
                goto cleanup;

        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);

        RUN_TESTS(sock_destroy_prog_fail);

cleanup:
        if (nstoken)
                close_netns(nstoken);
        SYS_NOFAIL("ip netns del " TEST_NS);
        if (cgroup_fd >= 0)
                close(cgroup_fd);
        sock_destroy_prog__destroy(skel);
}