Update Schannel Logic to Handler Larger Output Buffers (#4083)

Author: nibanks

src/generated/linux/tls_schannel.c.clog.h

@@ -99,6 +99,24 @@ tracepoint(CLOG_TLS_SCHANNEL_C, SchannelAchCompleteInline , arg2);\
 
 
 
+/*----------------------------------------------------------
+// Decoder Ring for SchannelOutBufferTooSmall
+// [conn][%p] Increasing TLS output buffer size
+// QuicTraceLogConnInfo(
+            SchannelOutBufferTooSmall,
+            TlsContext->Connection,
+            "Increasing TLS output buffer size");
+// arg1 = arg1 = TlsContext->Connection = arg1
+----------------------------------------------------------*/
+#ifndef _clog_3_ARGS_TRACE_SchannelOutBufferTooSmall
+#define _clog_3_ARGS_TRACE_SchannelOutBufferTooSmall(uniqueId, arg1, encoded_arg_string)\
+tracepoint(CLOG_TLS_SCHANNEL_C, SchannelOutBufferTooSmall , arg1);\
+
+#endif
+
+
+
+
 /*----------------------------------------------------------
 // Decoder Ring for SchannelHandshakeComplete
 // [conn][%p] Handshake complete (resume=%hu)

src/generated/linux/tls_schannel.c.clog.h.lttng.h

@@ -68,6 +68,25 @@ TRACEPOINT_EVENT(CLOG_TLS_SCHANNEL_C, SchannelAchCompleteInline,
 
 
 
+/*----------------------------------------------------------
+// Decoder Ring for SchannelOutBufferTooSmall
+// [conn][%p] Increasing TLS output buffer size
+// QuicTraceLogConnInfo(
+            SchannelOutBufferTooSmall,
+            TlsContext->Connection,
+            "Increasing TLS output buffer size");
+// arg1 = arg1 = TlsContext->Connection = arg1
+----------------------------------------------------------*/
+TRACEPOINT_EVENT(CLOG_TLS_SCHANNEL_C, SchannelOutBufferTooSmall,
+    TP_ARGS(
+        const void *, arg1), 
+    TP_FIELDS(
+        ctf_integer_hex(uint64_t, arg1, arg1)
+    )
+)
+
+
+
 /*----------------------------------------------------------
 // Decoder Ring for SchannelHandshakeComplete
 // [conn][%p] Handshake complete (resume=%hu)

src/manifest/clog.sidecar

@@ -9310,6 +9310,18 @@
       ],
       "macroName": "QuicTraceLogConnInfo"
     },
+    "SchannelOutBufferTooSmall": {
+      "ModuleProperites": {},
+      "TraceString": "[conn][%p] Increasing TLS output buffer size",
+      "UniqueId": "SchannelOutBufferTooSmall",
+      "splitArgs": [
+        {
+          "DefinationEncoding": "p",
+          "MacroVariableName": "arg1"
+        }
+      ],
+      "macroName": "QuicTraceLogConnInfo"
+    },
     "SchannelProcessingData": {
       "ModuleProperites": {},
       "TraceString": "[conn][%p] Processing %u received bytes",
@@ -15279,6 +15291,11 @@
         "TraceID": "SchannelMissingData",
         "EncodingString": "[conn][%p] TLS message missing %u bytes of data"
       },
+      {
+        "UniquenessHash": "71eb6726-56e9-ad9d-83d2-930ce22a51f3",
+        "TraceID": "SchannelOutBufferTooSmall",
+        "EncodingString": "[conn][%p] Increasing TLS output buffer size"
+      },
       {
         "UniquenessHash": "183e91b7-6ad7-7a8b-0d77-94004bde6757",
         "TraceID": "SchannelProcessingData",

src/platform/tls_schannel.c

@@ -2123,6 +2123,45 @@ CxPlatTlsWriteDataToSchannel(
     }
 
     switch (SecStatus) {
+    case SEC_E_BUFFER_TOO_SMALL: {
+        //
+        // The output buffer for the TLS response is too small. We need to grow
+        // the buffer and try again.
+        //
+        QuicTraceLogConnInfo(
+            SchannelOutBufferTooSmall,
+            TlsContext->Connection,
+            "Increasing TLS output buffer size");
+        uint16_t NewBufferLength = State->BufferAllocLength << 1;
+        if (NewBufferLength < State->BufferAllocLength) { // Integer overflow.
+            QuicTraceEvent(
+                TlsError,
+                "[ tls][%p] ERROR, %s.",
+                TlsContext->Connection,
+                "TLS buffer too large");
+            Result |= CXPLAT_TLS_RESULT_ERROR;
+            break;
+        }
+        uint8_t* NewBuffer = CXPLAT_ALLOC_NONPAGED(NewBufferLength, QUIC_POOL_TLS_BUFFER);
+        if (NewBuffer == NULL) {
+            QuicTraceEvent(
+                AllocFailure,
+                "Allocation of '%s' failed. (%llu bytes)",
+                "New TLS RX Buffer",
+                NewBufferLength);
+            Result |= CXPLAT_TLS_RESULT_ERROR;
+            break;
+        }
+        if (State->BufferLength) {
+            CxPlatCopyMemory(NewBuffer, State->Buffer, State->BufferLength);
+        }
+        CXPLAT_FREE(State->Buffer, QUIC_POOL_TLS_BUFFER);
+        State->Buffer = NewBuffer;
+        State->BufferAllocLength = NewBufferLength;
+        Result |= CXPLAT_TLS_RESULT_CONTINUE;
+        break;
+    }
+
     case SEC_E_OK:
 
         //

src/test/lib/HandshakeTest.cpp

@@ -221,7 +221,7 @@ QuicTestConnect(
     }
 
     StatelessRetryHelper RetryHelper(ServerStatelessRetry);
-    PrivateTransportHelper TpHelper(MultiPacketClientInitial);
+    PrivateTransportHelper TpHelper(MultiPacketClientInitial, !!ResumptionTicket);
     RandomLossHelper LossHelper(RandomLossPercentage);
 
     {

src/test/lib/TestHelpers.h

@@ -319,14 +319,15 @@ struct StatelessRetryHelper
 
 #define PRIVATE_TP_TYPE   77
 #define PRIVATE_TP_LENGTH 2345
+#define PRIVATE_TP_LENGTH_HUGE 4134
 
 struct PrivateTransportHelper : QUIC_PRIVATE_TRANSPORT_PARAMETER
 {
-    PrivateTransportHelper(bool Enabled) {
+    PrivateTransportHelper(bool Enabled, bool Resumption = false) {
         if (Enabled) {
             Type = PRIVATE_TP_TYPE;
-            Length = PRIVATE_TP_LENGTH;
-            Buffer = new(std::nothrow) uint8_t[PRIVATE_TP_LENGTH];
+            Length = Resumption ? PRIVATE_TP_LENGTH : PRIVATE_TP_LENGTH_HUGE;
+            Buffer = new(std::nothrow) uint8_t[Length];
             TEST_TRUE(Buffer != nullptr);
         } else {
             Buffer = nullptr;