On 7/1/20 12:46 PM, Martin KaFai Lau wrote:
This patch makes a few changes to the network_helpers.c

1) Enforce SO_RCVTIMEO and SO_SNDTIMEO
    This patch enforces timeout to the network fds through setsockopt
    SO_RCVTIMEO and SO_SNDTIMEO.

    It will remove the need for SOCK_NONBLOCK that requires a more demanding
    timeout logic with epoll/select, e.g. epoll_create, epoll_ctrl, and
    then epoll_wait for timeout.

    That removes the need for connect_wait() from the
    cgroup_skb_sk_lookup.c. The needed change is made in
    cgroup_skb_sk_lookup.c.

2) start_server():
    Add optional addr_str and port to start_server().
    That removes the need of the start_server_with_port().  The caller
    can pass addr_str==NULL and/or port==0.

    "int timeout_ms" is also added to control the timeout
    on the "accept(listen_fd)".

3) connect_to_fd(): Fully use the server_fd.
    The server sock address has already been obtained from
    getsockname(server_fd).  The sockaddr includes the family,
    so the "int family" arg is redundant.

    Since the server address is obtained from server_fd,  there
    is little reason not to get the server's socket type from the
    server_fd also.  getsockopt(server_fd) can be used to do that,
    so "int type" arg is also removed.

    "int timeout_ms" is added.

4) connect_fd_to_fd():
    "int timeout_ms" is added.
    Some code is also refactored to connect_fd_to_addr() which is
    shared with connect_to_fd().

5) Preserve errno:
    Some callers need to check errno, e.g. cgroup_skb_sk_lookup.c.
    Make changes to do it more consistently in save_errno_close()
    and log_err().

Signed-off-by: Martin KaFai Lau <ka...@fb.com>

LGTM. Ack with a few nits below.
Acked-by: Yonghong Song <y...@fb.com>

---
  tools/testing/selftests/bpf/network_helpers.c | 157 +++++++++++-------
  tools/testing/selftests/bpf/network_helpers.h |   9 +-
  .../bpf/prog_tests/cgroup_skb_sk_lookup.c     |  12 +-
  .../bpf/prog_tests/connect_force_port.c       |  10 +-
  .../bpf/prog_tests/load_bytes_relative.c      |   4 +-
  .../selftests/bpf/prog_tests/tcp_rtt.c        |   4 +-
  6 files changed, 110 insertions(+), 86 deletions(-)

diff --git a/tools/testing/selftests/bpf/network_helpers.c 
b/tools/testing/selftests/bpf/network_helpers.c
index e36dd1a1780d..1a371d3eca7d 100644
--- a/tools/testing/selftests/bpf/network_helpers.c
+++ b/tools/testing/selftests/bpf/network_helpers.c
@@ -7,8 +7,6 @@
#include <arpa/inet.h> -#include <sys/epoll.h>
-
  #include <linux/err.h>
  #include <linux/in.h>
  #include <linux/in6.h>
@@ -17,8 +15,13 @@
  #include "network_helpers.h"
#define clean_errno() (errno == 0 ? "None" : strerror(errno))
-#define log_err(MSG, ...) fprintf(stderr, "(%s:%d: errno: %s) " MSG "\n", \
-       __FILE__, __LINE__, clean_errno(), ##__VA_ARGS__)
+#define log_err(MSG, ...) ({                                           \
+                       int save = errno;                               \

Typicallty, the variables used inside macro started with __, e.g.,
__save, to avoie shadowing.

+                       fprintf(stderr, "(%s:%d: errno: %s) " MSG "\n", \
+                               __FILE__, __LINE__, clean_errno(),      \
+                               ##__VA_ARGS__);                         \
+                       errno = save;                                   \
+})
struct ipv4_packet pkt_v4 = {
        .eth.h_proto = __bpf_constant_htons(ETH_P_IP),
@@ -37,7 +40,34 @@ struct ipv6_packet pkt_v6 = {
        .tcp.doff = 5,
  };
-int start_server_with_port(int family, int type, __u16 port)
+static int settimeo(int fd, int timeout_ms)
+{
+       struct timeval timeout = { .tv_sec = 3 };
+
+       if (timeout_ms > 0) {
+               timeout.tv_sec = timeout_ms / 1000;
+               timeout.tv_usec = (timeout_ms % 1000) * 1000;
+       }
+
+       if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout,
+                      sizeof(timeout))) {
+               log_err("Failed to set SO_RCVTIMEO");
+               return -1;
+       }
+
+       if (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeout,
+                      sizeof(timeout))) {
+               log_err("Failed to set SO_SNDTIMEO");
+               return -1;
+       }
+
+       return 0;
+}
+
+#define save_errno_close(fd) ({ int save = errno; close(fd); errno = save; })
+
+int start_server(int family, int type, const char *addr_str, __u16 port,
+                int timeout_ms)

Looks like non-NULL addr_str is not passed in all existing cased.
I guess this is for your later use case. It would be good to clarify
in the commit message.

  {
        struct sockaddr_storage addr = {};
        socklen_t len;
@@ -48,120 +78,119 @@ int start_server_with_port(int family, int type, __u16 
port)
sin->sin_family = AF_INET;
                sin->sin_port = htons(port);
+               if (addr_str &&
+                   inet_pton(AF_INET, addr_str, &sin->sin_addr) != 1) {
+                       log_err("inet_pton(AF_INET, %s)", addr_str);
+                       return -1;
+               }
                len = sizeof(*sin);
        } else {
                struct sockaddr_in6 *sin6 = (void *)&addr;
sin6->sin6_family = AF_INET6;
                sin6->sin6_port = htons(port);
+               if (addr_str &&
+                   inet_pton(AF_INET6, addr_str, &sin6->sin6_addr) != 1) {
+                       log_err("inet_pton(AF_INET6, %s)", addr_str);
+                       return -1;
+               }
                len = sizeof(*sin6);
        }
- fd = socket(family, type | SOCK_NONBLOCK, 0);
+       fd = socket(family, type, 0);
        if (fd < 0) {
                log_err("Failed to create server socket");
                return -1;
        }
+ if (settimeo(fd, timeout_ms))
+               goto error_close;
+
        if (bind(fd, (const struct sockaddr *)&addr, len) < 0) {
                log_err("Failed to bind socket");
-               close(fd);
-               return -1;
+               goto error_close;
        }
if (type == SOCK_STREAM) {
                if (listen(fd, 1) < 0) {
                        log_err("Failed to listed on socket");
-                       close(fd);
-                       return -1;
+                       goto error_close;
                }
        }
return fd;
-}
-int start_server(int family, int type)
-{
-       return start_server_with_port(family, type, 0);
+error_close:
+       save_errno_close(fd);
+       return -1;
  }
[...]
diff --git a/tools/testing/selftests/bpf/prog_tests/connect_force_port.c 
b/tools/testing/selftests/bpf/prog_tests/connect_force_port.c
index 17bbf76812ca..9229db2f5ca5 100644
--- a/tools/testing/selftests/bpf/prog_tests/connect_force_port.c
+++ b/tools/testing/selftests/bpf/prog_tests/connect_force_port.c
@@ -114,7 +114,7 @@ static int run_test(int cgroup_fd, int server_fd, int 
family, int type)
                goto close_bpf_object;
        }
- fd = connect_to_fd(family, type, server_fd);
+       fd = connect_to_fd(server_fd, 0);
        if (fd < 0) {
                err = -1;
                goto close_bpf_object;
@@ -137,25 +137,25 @@ void test_connect_force_port(void)
        if (CHECK_FAIL(cgroup_fd < 0))
                return;
- server_fd = start_server_with_port(AF_INET, SOCK_STREAM, 60123);
+       server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 60123, 0);
        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_with_port(AF_INET6, SOCK_STREAM, 60124);
+       server_fd = start_server(AF_INET6, SOCK_STREAM, NULL, 60124, 0);
        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_with_port(AF_INET, SOCK_DGRAM, 60123);
+       server_fd = start_server(AF_INET, SOCK_DGRAM, NULL, 60123, 0);
        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_with_port(AF_INET6, SOCK_DGRAM, 60124);
+       server_fd = start_server(AF_INET6, SOCK_DGRAM, NULL, 60124, 0);
        if (CHECK_FAIL(server_fd < 0))
                goto close_cgroup_fd;
        CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET6, SOCK_DGRAM));
diff --git a/tools/testing/selftests/bpf/prog_tests/load_bytes_relative.c 
b/tools/testing/selftests/bpf/prog_tests/load_bytes_relative.c
index c1168e4a9036..5a2a689dbb68 100644
--- a/tools/testing/selftests/bpf/prog_tests/load_bytes_relative.c
+++ b/tools/testing/selftests/bpf/prog_tests/load_bytes_relative.c
@@ -23,7 +23,7 @@ void test_load_bytes_relative(void)
        if (CHECK_FAIL(cgroup_fd < 0))
                return;
- server_fd = start_server(AF_INET, SOCK_STREAM);
+       server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0);
        if (CHECK_FAIL(server_fd < 0))
                goto close_cgroup_fd;
@@ -49,7 +49,7 @@ void test_load_bytes_relative(void)
        if (CHECK_FAIL(err))
                goto close_bpf_object;
- client_fd = connect_to_fd(AF_INET, SOCK_STREAM, server_fd);
+       client_fd = connect_to_fd(server_fd, 0);
        if (CHECK_FAIL(client_fd < 0))
                goto close_bpf_object;
        close(client_fd);
diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c 
b/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
index 9013a0c01eed..d207e968e6b1 100644
--- a/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
+++ b/tools/testing/selftests/bpf/prog_tests/tcp_rtt.c
@@ -118,7 +118,7 @@ static int run_test(int cgroup_fd, int server_fd)
                goto close_bpf_object;
        }
- client_fd = connect_to_fd(AF_INET, SOCK_STREAM, server_fd);
+       client_fd = connect_to_fd(server_fd, 0);
        if (client_fd < 0) {
                err = -1;
                goto close_bpf_object;
@@ -161,7 +161,7 @@ void test_tcp_rtt(void)
        if (CHECK_FAIL(cgroup_fd < 0))
                return;
- server_fd = start_server(AF_INET, SOCK_STREAM);
+       server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0);
        if (CHECK_FAIL(server_fd < 0))
                goto close_cgroup_fd;

Reply via email to