Handle TCP segment split cases as per MSS.

- Always split segments larger than MSS.
  Currently, we base the segment split decision as a function of the
  send congestion window and MSS, which could be greater than the MSS
  advertised by remote.
- While splitting segments, ensure the PSH flag is reset when there
  are segments that are queued to be sent.
- With TCP_CORK, hold up segments up until MSS. Fix a bug in computing
  available send space before attempting to coalesce segments.

Fixes #2832

PiperOrigin-RevId: 314802928

1 files changed, 20 insertions, 0 deletions

diff --git a/test/packetimpact/tests/BUILD b/test/packetimpact/tests/BUILD
index fb39ee4b8..2a41ef326 100644
--- a/test/packetimpact/tests/BUILD
+++ b/test/packetimpact/tests/BUILD
@@ -200,6 +200,26 @@ packetimpact_go_test(
 )
 
 packetimpact_go_test(
+    name = "tcp_splitseg_mss",
+    srcs = ["tcp_splitseg_mss_test.go"],
+    deps = [
+        "//pkg/tcpip/header",
+        "//test/packetimpact/testbench",
+        "@org_golang_x_sys//unix:go_default_library",
+    ],
+)
+
+packetimpact_go_test(
+    name = "tcp_cork_mss",
+    srcs = ["tcp_cork_mss_test.go"],
+    deps = [
+        "//pkg/tcpip/header",
+        "//test/packetimpact/testbench",
+        "@org_golang_x_sys//unix:go_default_library",
+    ],
+)
+
+packetimpact_go_test(
     name = "icmpv6_param_problem",
     srcs = ["icmpv6_param_problem_test.go"],
     # TODO(b/153485026): Fix netstack then remove the line below.