test/system: pasta_test_do add explicit port check

Do not rely on an arbitrary delay in order to ensure the port was bound
in the container. Instead this approach checks if the port is bound in
the netns and only then starts the client. This speeds up the entire
test file by 50% but more importantly in parallel testing it solves
hangs as the timeout there was unreliable.

Fixes containers#23471

Signed-off-by: Paul Holzinger <[email protected]>

test/system/505-networking-pasta.bats

@@ -209,34 +209,52 @@ function pasta_test_do() {
         local expect="$(for i in $(seq ${seq}); do printf "x"; done)"
     fi
 
-    # Set retry/initial delay for client to connect
-    local delay=1
-    if [ ${ip_ver} -eq 6 ] && [ "${addr}" != "::1" ]; then
-        # Duplicate Address Detection on link-local
-        delay=3
-    elif [ "${proto}" = "udp" ]; then
-        # With Podman up, and socat still starting, UDP clients send to nowhere
-        delay=2
+    # Start server
+    local cname="c-socat-$(safename)"
+    run_podman run -d --name="$cname" --net=pasta"${pasta_spec}" -p "${podman_spec}" "${IMAGE}" \
+                   sh -c 'for port in $(seq '"${xseq}"'); do '\
+'                             socat -u '"${bind}"' '"${recv}"' & '\
+'                         done; wait'
+
+    # Make sure all ports in the container are bound.
+    for cport in $(seq ${xseq}); do
+        retries=50
+        while [[ $retries -gt 0 ]]; do
+            run_podman exec $cname ss -Hln -$ip_ver --$proto sport = "$cport"
+            if [[ "$output" =~ "$cport" ]]; then
+                break
+            fi
+            retries=$((retries - 1))
+            sleep 0.1
+        done
+        assert $retries -gt 0 "Timed out waiting for bound port $cport in container"
+    done
+
+    if [ ${ip_ver} -eq 6 ] && [ ${iftype} = "tap" ]; then
+        # For IPv6 tests via tap interface, we use pairs of link-local
+        # addresses to communicate. While we disable DAD on all the
+        # (global unicast) addresses we copy from the host, or
+        # otherwise set, link-local addresses are automatically added
+        # by the kernel with DAD, so we need to wait until it's done.
+        sleep 2
     fi
 
-    # Now actually run the test: client,
-    for one_port in $(seq ${seq}); do
-        local connect="${proto_upper}${ip_ver}:[${addr}]:${one_port}"
+    for hport in $(seq ${seq}); do
+        local connect="${proto_upper}${ip_ver}:[${addr}]:${hport}"
         [ "${proto}" = "udp" ] && connect="${connect},shut-null"
-
-        local retries=10
-        (while sleep ${delay} && test $((retries--)) -gt 0 && ! timeout --foreground -v --kill=5 90 socat -u "OPEN:${XFER_FILE}" "${connect}"; do :
-         done) &
+        # Ports are bound: we can start the client in the background.
+        timeout --foreground -v --kill=5 90 socat -u "OPEN:${XFER_FILE}" "${connect}" &
     done
 
-    # and server,
-    run_podman run --rm --net=pasta"${pasta_spec}" -p "${podman_spec}" "${IMAGE}" \
-                   sh -c 'for port in $(seq '"${xseq}"'); do '\
-'                             socat -u '"${bind}"' '"${recv}"' & '\
-'                         done; wait'
+    # Wait for the client children to finish.
+    wait
 
+    # Get server output, --follow is used to wait for the container to exit,
+    run_podman logs --follow $cname
     # which should give us the expected output back.
     assert "${output}" = "${expect}" "Mismatch between data sent and received"
+
+    run_podman rm $cname
 }
 
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