bpf: Adjust bpf_tcp_check_syncookie selftest to test dual-stack sockets

The previous commit fixed support for dual-stack sockets in
bpf_tcp_check_syncookie. This commit adjusts the selftest to verify the
fixed functionality.

Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Arthur Fabre <afabre@cloudflare.com>
Link: https://lore.kernel.org/bpf/20220406124113.2795730-2-maximmi@nvidia.com

diff --git a/tools/testing/selftests/bpf/test_tcp_check_syncookie_user.c b/tools/testing/selftests/bpf/test_tcp_check_syncookie_user.c
index b9e991d..e7775d3 100644 (file)
--- a/tools/testing/selftests/bpf/test_tcp_check_syncookie_user.c
+++ b/tools/testing/selftests/bpf/test_tcp_check_syncookie_user.c
@@ -18,8 +18,9 @@
 #include "bpf_rlimit.h"
 #include "cgroup_helpers.h"
 
-static int start_server(const struct sockaddr *addr, socklen_t len)
+static int start_server(const struct sockaddr *addr, socklen_t len, bool dual)
 {
+       int mode = !dual;
        int fd;
 
        fd = socket(addr->sa_family, SOCK_STREAM, 0);
@@ -28,6 +29,14 @@ static int start_server(const struct sockaddr *addr, socklen_t len)
                goto out;
        }
 
+       if (addr->sa_family == AF_INET6) {
+               if (setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&mode,
+                              sizeof(mode)) == -1) {
+                       log_err("Failed to set the dual-stack mode");
+                       goto close_out;
+               }
+       }
+
        if (bind(fd, addr, len) == -1) {
                log_err("Failed to bind server socket");
                goto close_out;
@@ -47,24 +56,17 @@ out:
        return fd;
 }
 
-static int connect_to_server(int server_fd)
+static int connect_to_server(const struct sockaddr *addr, socklen_t len)
 {
-       struct sockaddr_storage addr;
-       socklen_t len = sizeof(addr);
        int fd = -1;
 
-       if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
-               log_err("Failed to get server addr");
-               goto out;
-       }
-
-       fd = socket(addr.ss_family, SOCK_STREAM, 0);
+       fd = socket(addr->sa_family, SOCK_STREAM, 0);
        if (fd == -1) {
                log_err("Failed to create client socket");
                goto out;
        }
 
-       if (connect(fd, (const struct sockaddr *)&addr, len) == -1) {
+       if (connect(fd, (const struct sockaddr *)addr, len) == -1) {
                log_err("Fail to connect to server");
                goto close_out;
        }
@@ -116,7 +118,8 @@ err:
        return map_fd;
 }
 
-static int run_test(int server_fd, int results_fd, bool xdp)
+static int run_test(int server_fd, int results_fd, bool xdp,
+                   const struct sockaddr *addr, socklen_t len)
 {
        int client = -1, srv_client = -1;
        int ret = 0;
@@ -142,7 +145,7 @@ static int run_test(int server_fd, int results_fd, bool xdp)
                goto err;
        }
 
-       client = connect_to_server(server_fd);
+       client = connect_to_server(addr, len);
        if (client == -1)
                goto err;
 
@@ -199,12 +202,30 @@ out:
        return ret;
 }
 
+static bool get_port(int server_fd, in_port_t *port)
+{
+       struct sockaddr_in addr;
+       socklen_t len = sizeof(addr);
+
+       if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
+               log_err("Failed to get server addr");
+               return false;
+       }
+
+       /* sin_port and sin6_port are located at the same offset. */
+       *port = addr.sin_port;
+       return true;
+}
+
 int main(int argc, char **argv)
 {
        struct sockaddr_in addr4;
        struct sockaddr_in6 addr6;
+       struct sockaddr_in addr4dual;
+       struct sockaddr_in6 addr6dual;
        int server = -1;
        int server_v6 = -1;
+       int server_dual = -1;
        int results = -1;
        int err = 0;
        bool xdp;
@@ -224,25 +245,43 @@ int main(int argc, char **argv)
        addr4.sin_family = AF_INET;
        addr4.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
        addr4.sin_port = 0;
+       memcpy(&addr4dual, &addr4, sizeof(addr4dual));
 
        memset(&addr6, 0, sizeof(addr6));
        addr6.sin6_family = AF_INET6;
        addr6.sin6_addr = in6addr_loopback;
        addr6.sin6_port = 0;
 
-       server = start_server((const struct sockaddr *)&addr4, sizeof(addr4));
-       if (server == -1)
+       memset(&addr6dual, 0, sizeof(addr6dual));
+       addr6dual.sin6_family = AF_INET6;
+       addr6dual.sin6_addr = in6addr_any;
+       addr6dual.sin6_port = 0;
+
+       server = start_server((const struct sockaddr *)&addr4, sizeof(addr4),
+                             false);
+       if (server == -1 || !get_port(server, &addr4.sin_port))
                goto err;
 
        server_v6 = start_server((const struct sockaddr *)&addr6,
-                                sizeof(addr6));
-       if (server_v6 == -1)
+                                sizeof(addr6), false);
+       if (server_v6 == -1 || !get_port(server_v6, &addr6.sin6_port))
+               goto err;
+
+       server_dual = start_server((const struct sockaddr *)&addr6dual,
+                                  sizeof(addr6dual), true);
+       if (server_dual == -1 || !get_port(server_dual, &addr4dual.sin_port))
+               goto err;
+
+       if (run_test(server, results, xdp,
+                    (const struct sockaddr *)&addr4, sizeof(addr4)))
                goto err;
 
-       if (run_test(server, results, xdp))
+       if (run_test(server_v6, results, xdp,
+                    (const struct sockaddr *)&addr6, sizeof(addr6)))
                goto err;
 
-       if (run_test(server_v6, results, xdp))
+       if (run_test(server_dual, results, xdp,
+                    (const struct sockaddr *)&addr4dual, sizeof(addr4dual)))
                goto err;
 
        printf("ok\n");
@@ -252,6 +291,7 @@ err:
 out:
        close(server);
        close(server_v6);
+       close(server_dual);
        close(results);
        return err;
 }