Implement {g,s}etsockopt(IP_RECVTOS) for UDP sockets

PiperOrigin-RevId: 289718534

2 files changed, 45 insertions, 3 deletions

diff --git a/test/syscalls/linux/socket_ip_udp_generic.cc b/test/syscalls/linux/socket_ip_udp_generic.cc
index 66eb68857..53290bed7 100644
--- a/test/syscalls/linux/socket_ip_udp_generic.cc
+++ b/test/syscalls/linux/socket_ip_udp_generic.cc
@@ -209,6 +209,46 @@ TEST_P(UDPSocketPairTest, SetMulticastLoopChar) {
   EXPECT_EQ(get, kSockOptOn);
 }
 
+// Ensure that Receiving TOS is off by default.
+TEST_P(UDPSocketPairTest, RecvTosDefault) {
+  auto sockets = ASSERT_NO_ERRNO_AND_VALUE(NewSocketPair());
+
+  int get = -1;
+  socklen_t get_len = sizeof(get);
+  ASSERT_THAT(
+      getsockopt(sockets->first_fd(), IPPROTO_IP, IP_RECVTOS, &get, &get_len),
+      SyscallSucceedsWithValue(0));
+  EXPECT_EQ(get_len, sizeof(get));
+  EXPECT_EQ(get, kSockOptOff);
+}
+
+// Test that setting and getting IP_RECVTOS works as expected.
+TEST_P(UDPSocketPairTest, SetRecvTos) {
+  auto sockets = ASSERT_NO_ERRNO_AND_VALUE(NewSocketPair());
+
+  ASSERT_THAT(setsockopt(sockets->first_fd(), IPPROTO_IP, IP_RECVTOS,
+                         &kSockOptOff, sizeof(kSockOptOff)),
+              SyscallSucceeds());
+
+  int get = -1;
+  socklen_t get_len = sizeof(get);
+  ASSERT_THAT(
+      getsockopt(sockets->first_fd(), IPPROTO_IP, IP_RECVTOS, &get, &get_len),
+      SyscallSucceedsWithValue(0));
+  EXPECT_EQ(get_len, sizeof(get));
+  EXPECT_EQ(get, kSockOptOff);
+
+  ASSERT_THAT(setsockopt(sockets->first_fd(), IPPROTO_IP, IP_RECVTOS,
+                         &kSockOptOn, sizeof(kSockOptOn)),
+              SyscallSucceeds());
+
+  ASSERT_THAT(
+      getsockopt(sockets->first_fd(), IPPROTO_IP, IP_RECVTOS, &get, &get_len),
+      SyscallSucceedsWithValue(0));
+  EXPECT_EQ(get_len, sizeof(get));
+  EXPECT_EQ(get, kSockOptOn);
+}
+
 TEST_P(UDPSocketPairTest, ReuseAddrDefault) {
   auto sockets = ASSERT_NO_ERRNO_AND_VALUE(NewSocketPair());
 
diff --git a/test/syscalls/linux/udp_socket_test_cases.cc b/test/syscalls/linux/udp_socket_test_cases.cc
index dc35c2f50..68e0a8109 100644
--- a/test/syscalls/linux/udp_socket_test_cases.cc
+++ b/test/syscalls/linux/udp_socket_test_cases.cc
@@ -1349,8 +1349,9 @@ TEST_P(UdpSocketTest, TimestampIoctlPersistence) {
 // outgoing packets, and that a receiving socket with IP_RECVTOS or
 // IPV6_RECVTCLASS will create the corresponding control message.
 TEST_P(UdpSocketTest, SetAndReceiveTOS) {
-  // TODO(b/68320120): IP_RECVTOS/IPV6_RECVTCLASS not supported for netstack.
-  SKIP_IF(IsRunningOnGvisor() && !IsRunningWithHostinet());
+  // TODO(b/68320120): IPV6_RECVTCLASS not supported for netstack.
+  SKIP_IF((GetParam() != AddressFamily::kIpv4) && IsRunningOnGvisor() &&
+          !IsRunningWithHostinet());
   ASSERT_THAT(bind(s_, addr_[0], addrlen_), SyscallSucceeds());
   ASSERT_THAT(connect(t_, addr_[0], addrlen_), SyscallSucceeds());
 
@@ -1421,7 +1422,8 @@ TEST_P(UdpSocketTest, SetAndReceiveTOS) {
 // TOS byte on outgoing packets, and that a receiving socket with IP_RECVTOS or
 // IPV6_RECVTCLASS will create the corresponding control message.
 TEST_P(UdpSocketTest, SendAndReceiveTOS) {
-  // TODO(b/68320120): IP_RECVTOS/IPV6_RECVTCLASS not supported for netstack.
+  // TODO(b/68320120): IPV6_RECVTCLASS not supported for netstack.
+  // TODO(b/146661005): Setting TOS via cmsg not supported for netstack.
   SKIP_IF(IsRunningOnGvisor() && !IsRunningWithHostinet());
   ASSERT_THAT(bind(s_, addr_[0], addrlen_), SyscallSucceeds());
   ASSERT_THAT(connect(t_, addr_[0], addrlen_), SyscallSucceeds());