From 7c08057b3bc3b15ea26a3480758897de1345b1ca Mon Sep 17 00:00:00 2001
From: Jack He <jackhe@microsoft.com>
Date: Tue, 15 Oct 2024 14:50:34 -0700
Subject: [PATCH] implement raw socket parsing and add stubs for freeBSD and
 linux

---
 src/core/connection.c              | 1 -
 src/platform/datapath_epoll.c      | 2 ++
 src/platform/datapath_kqueue.c     | 1 +
 src/platform/datapath_raw_socket.c | 2 ++
 4 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/core/connection.c b/src/core/connection.c
index 73be15cdea..6a1375c1fa 100644
--- a/src/core/connection.c
+++ b/src/core/connection.c
@@ -5511,7 +5511,6 @@ QuicConnRecvDatagramBatch(
         CXPLAT_DBG_ASSERT(Packets[i]->Allocated);
         CXPLAT_ECN_TYPE ECN = CXPLAT_ECN_FROM_TOS(Packets[i]->TypeOfService);
         Packet = Packets[i];
-
         CXPLAT_DBG_ASSERT(Packet->PacketId != 0);
         if (!QuicConnRecvPrepareDecrypt(
                 Connection, Packet, HpMask + i * CXPLAT_HP_SAMPLE_LENGTH) ||
diff --git a/src/platform/datapath_epoll.c b/src/platform/datapath_epoll.c
index b02152376e..f4a72d0989 100644
--- a/src/platform/datapath_epoll.c
+++ b/src/platform/datapath_epoll.c
@@ -1782,6 +1782,7 @@ CxPlatSocketContextRecvComplete(
         BytesTransferred += RecvMsgHdr[CurrentMessage].msg_len;
 
         uint8_t TOS = 0;
+        uint8_t HopLimitTTL = 0;
         uint16_t SegmentLength = 0;
         BOOLEAN FoundLocalAddr = FALSE, FoundTOS = FALSE;
         QUIC_ADDR* LocalAddr = &IoBlock->Route.LocalAddress;
@@ -1872,6 +1873,7 @@ CxPlatSocketContextRecvComplete(
             }
             RecvData->PartitionIndex = SocketContext->DatapathPartition->PartitionIndex;
             RecvData->TypeOfService = TOS;
+            RecvData->HopLimitTTL = 0; // TODO: Set the right Linux socket options and get the TTL.
             RecvData->Allocated = TRUE;
             RecvData->Route->DatapathType = RecvData->DatapathType = CXPLAT_DATAPATH_TYPE_USER;
             RecvData->QueuedOnConnection = FALSE;
diff --git a/src/platform/datapath_kqueue.c b/src/platform/datapath_kqueue.c
index 12aabccb68..bb75c009cd 100644
--- a/src/platform/datapath_kqueue.c
+++ b/src/platform/datapath_kqueue.c
@@ -1127,6 +1127,7 @@ CxPlatSocketContextRecvComplete(
 
     RecvPacket->Route->Queue = SocketContext;
     RecvPacket->TypeOfService = 0;
+    RecvPacket->HopLimitTTL = 0; // TODO: Check to see if it's even possible to get this information on macOS and FreeBSD. If so, implement it. Otherwise, document that it's not supported.
 
     struct cmsghdr *CMsg;
     for (CMsg = CMSG_FIRSTHDR(&SocketContext->RecvMsgHdr);
diff --git a/src/platform/datapath_raw_socket.c b/src/platform/datapath_raw_socket.c
index e0a31c07da..9368a7bcd0 100644
--- a/src/platform/datapath_raw_socket.c
+++ b/src/platform/datapath_raw_socket.c
@@ -298,6 +298,7 @@ CxPlatDpRawParseIPv4(
     }
 
     Packet->TypeOfService = IP->EcnField;
+    Packet->HopLimitTTL = IP->TimeToLive;
     Packet->Route->RemoteAddress.Ipv4.sin_family = AF_INET;
     CxPlatCopyMemory(&Packet->Route->RemoteAddress.Ipv4.sin_addr, IP->Source, sizeof(IP->Source));
     Packet->Route->LocalAddress.Ipv4.sin_family = AF_INET;
@@ -366,6 +367,7 @@ CxPlatDpRawParseIPv6(
     VersionClassEcnFlow.Value = CxPlatByteSwapUint32(IP->VersionClassEcnFlow);
 
     Packet->TypeOfService = (uint8_t)VersionClassEcnFlow.EcnField;
+    Packet->HopLimitTTL = IP->HopLimit;
     Packet->Route->RemoteAddress.Ipv6.sin6_family = AF_INET6;
     CxPlatCopyMemory(&Packet->Route->RemoteAddress.Ipv6.sin6_addr, IP->Source, sizeof(IP->Source));
     Packet->Route->LocalAddress.Ipv6.sin6_family = AF_INET6;