Hi Tiago,
On 2024/9/13 17:39, Tiago Lam wrote:
This patch reuses the framework already in place for sk_lookup, allowing
it now to send a reply from the server fd directly, instead of having to
create a socket bound to the original destination address and reply from
there. It does this by passing the source address and port from where to
reply from in a IP_ORIGDSTADDR ancilliary message passed in sendmsg.
Signed-off-by: Tiago Lam <tiagolam@xxxxxxxxxxxxxx>
---
tools/testing/selftests/bpf/prog_tests/sk_lookup.c | 70 +++++++++++++++-------
1 file changed, 48 insertions(+), 22 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/sk_lookup.c b/tools/testing/selftests/bpf/prog_tests/sk_lookup.c
index ae87c00867ba..b99aff2e3976 100644
--- a/tools/testing/selftests/bpf/prog_tests/sk_lookup.c
+++ b/tools/testing/selftests/bpf/prog_tests/sk_lookup.c
@@ -75,6 +75,7 @@ struct test {
struct inet_addr listen_at;
enum server accept_on;
bool reuseport_has_conns; /* Add a connected socket to reuseport group */
+ bool dont_bind_reply; /* Don't bind, send direct from server fd. */
};
struct cb_opts {
@@ -363,7 +364,7 @@ static void v4_to_v6(struct sockaddr_storage *ss)
memset(&v6->sin6_addr.s6_addr[0], 0, 10);
}
-static int udp_recv_send(int server_fd)
+static int udp_recv_send(int server_fd, bool dont_bind_reply)
{
char cmsg_buf[CMSG_SPACE(sizeof(struct sockaddr_storage))];
struct sockaddr_storage _src_addr = { 0 };
@@ -415,26 +416,41 @@ static int udp_recv_send(int server_fd)
v4_to_v6(dst_addr);
}
- /* Reply from original destination address. */
- fd = start_server_addr(SOCK_DGRAM, dst_addr, sizeof(*dst_addr), NULL);
- if (!ASSERT_OK_FD(fd, "start_server_addr")) {
- log_err("failed to create tx socket");
- return -1;
- }
+ if (dont_bind_reply) {
+ /* Reply directly from server fd, specifying the source address and/or
+ * port in struct msghdr.
+ */
+ n = sendmsg(server_fd, &msg, 0);
+ if (CHECK(n <= 0, "sendmsg", "failed\n")) {
+ log_err("failed to send echo reply");
+ return -1;
+ }
+ } else {
+ /* Reply from original destination address. */
+ fd = socket(dst_addr->ss_family, SOCK_DGRAM, 0);
+ if (CHECK(fd < 0, "socket", "failed\n")) {
+ log_err("failed to create tx socket");
+ return -1;
+ }
Just curious, why not use start_server_addr() here like before?
- msg.msg_control = NULL;
- msg.msg_controllen = 0;
- n = sendmsg(fd, &msg, 0);
- if (CHECK(n <= 0, "sendmsg", "failed\n")) {
- log_err("failed to send echo reply");
- ret = -1;
- goto out;
- }
+ ret = bind(fd, (struct sockaddr *)dst_addr, sizeof(*dst_addr));
+ if (CHECK(ret, "bind", "failed\n")) {
+ log_err("failed to bind tx socket");
+ close(fd);
+ return ret;
+ }
- ret = 0;
-out:
- close(fd);
- return ret;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ n = sendmsg(fd, &msg, 0);
+ if (CHECK(n <= 0, "sendmsg", "failed\n")) {
+ log_err("failed to send echo reply");
+ close(fd);
+ return -1;
+ }
+
+ close(fd);
+ }
nit: "return 0" missed.
}
--
Philo
