From 891a10c4f6bb3e22af9f70d0699d2d93f73b1aca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Moreau?= <marcandre.moreau@gmail.com>
Date: Mon, 10 Mar 2014 15:57:39 -0400
Subject: [PATCH] libfreerdp-core: hook new MPPC decompressor

---
 libfreerdp/codec/mppc.c | 66 ++++++++++++++++++++++++++++++-----------
 libfreerdp/core/bulk.c  | 16 ++++++----
 2 files changed, 58 insertions(+), 24 deletions(-)

diff --git a/libfreerdp/codec/mppc.c b/libfreerdp/codec/mppc.c
index a0cc469a0..2b785ff82 100644
--- a/libfreerdp/codec/mppc.c
+++ b/libfreerdp/codec/mppc.c
@@ -79,41 +79,49 @@ UINT32 mppc_decompress(MPPC_CONTEXT* mppc, BYTE* pSrcData, BYTE** ppDstData, UIN
 	UINT32 CopyOffset;
 	UINT32 LengthOfMatch;
 	UINT32 accumulator;
-	BYTE* HistoryBuffer;
 	BYTE* HistoryPtr;
 	UINT32 HistoryOffset;
+	BYTE* HistoryBuffer;
+	BYTE* HistoryBufferEnd;
+	UINT32 HistoryBufferSize;
 	UINT32 CompressionLevel;
 	wBitStream* bs = mppc->bs;
 
 	HistoryBuffer = mppc->HistoryBuffer;
+	HistoryBufferSize = mppc->HistoryBufferSize;
+	HistoryBufferEnd = &HistoryBuffer[HistoryBufferSize - 1];
 	CompressionLevel = mppc->CompressionLevel;
 
-	*ppDstData = HistoryBuffer;
-
 	BitStream_Attach(bs, pSrcData, *pSize);
 	BitStream_Fetch(bs);
 
 	if (flags & PACKET_AT_FRONT)
 	{
-		mppc->HistoryPtr = &(HistoryBuffer[0]);
+		mppc->HistoryOffset = 0;
+		mppc->HistoryPtr = HistoryBuffer;
 	}
 
 	if (flags & PACKET_FLUSHED)
 	{
-		mppc->HistoryPtr = &(HistoryBuffer[0]);
+		mppc->HistoryOffset = 0;
+		mppc->HistoryPtr = HistoryBuffer;
 		ZeroMemory(HistoryBuffer, mppc->HistoryBufferSize);
 	}
 
-	if (!(flags & PACKET_COMPRESSED))
-	{
-		CopyMemory(mppc->HistoryPtr, pSrcData, *pSize);
-		mppc->HistoryPtr += *pSize;
-		return 0;
-	}
-
 	HistoryPtr = mppc->HistoryPtr;
 	HistoryOffset = mppc->HistoryOffset;
 
+	if (!(flags & PACKET_COMPRESSED))
+	{
+		CopyMemory(HistoryPtr, pSrcData, *pSize);
+		HistoryPtr += *pSize;
+		HistoryOffset += *pSize;
+		mppc->HistoryPtr = HistoryPtr;
+		mppc->HistoryOffset = HistoryOffset;
+		*ppDstData = HistoryPtr;
+		return 1;
+	}
+
 	while ((bs->length - bs->position) >= 8)
 	{
 		accumulator = bs->accumulator;
@@ -414,22 +422,44 @@ UINT32 mppc_decompress(MPPC_CONTEXT* mppc, BYTE* pSrcData, BYTE** ppDstData, UIN
 
 		SrcPtr = HistoryPtr - CopyOffset;
 
-		while (LengthOfMatch > 0)
+		if (SrcPtr >= HistoryBuffer)
 		{
-			*(HistoryPtr) = *SrcPtr;
+			while (LengthOfMatch > 0)
+			{
+				*(HistoryPtr) = *SrcPtr;
 
-			HistoryPtr++;
+				HistoryPtr++;
+				SrcPtr++;
+
+				LengthOfMatch--;
+			}
+		}
+		else
+		{
+			SrcPtr = HistoryBufferEnd - (CopyOffset - (HistoryPtr - HistoryBuffer));
 			SrcPtr++;
 
-			LengthOfMatch--;
+			while (LengthOfMatch && (SrcPtr <= HistoryBufferEnd))
+			{
+				*HistoryPtr++ = *SrcPtr++;
+				LengthOfMatch--;
+			}
+
+			SrcPtr = HistoryBuffer;
+
+			while (LengthOfMatch > 0)
+			{
+				*HistoryPtr++ = *SrcPtr++;
+				LengthOfMatch--;
+			}
 		}
 	}
 
 	*pSize = (UINT32) (HistoryPtr - mppc->HistoryPtr);
-
+	*ppDstData = mppc->HistoryPtr;
 	mppc->HistoryPtr = HistoryPtr;
 
-	return 0;
+	return 1;
 }
 
 UINT32 mppc_compress(MPPC_CONTEXT* mppc, BYTE* pSrcData, BYTE* pDstData, UINT32* pSize)
diff --git a/libfreerdp/core/bulk.c b/libfreerdp/core/bulk.c
index 607e765c7..ba905f533 100644
--- a/libfreerdp/core/bulk.c
+++ b/libfreerdp/core/bulk.c
@@ -26,6 +26,7 @@
 int bulk_decompress(rdpBulk* bulk, BYTE* pSrcData, UINT32 SrcSize, BYTE** ppDstData, UINT32* pDstSize, UINT32 flags)
 {
 	int status = -1;
+	UINT32 size;
 	UINT32 roff = 0;
 	UINT32 rlen = 0;
 	UINT32 type = flags & 0x0F;
@@ -33,15 +34,18 @@ int bulk_decompress(rdpBulk* bulk, BYTE* pSrcData, UINT32 SrcSize, BYTE** ppDstD
 	switch (type)
 	{
 		case PACKET_COMPR_TYPE_8K:
-			status = decompress_rdp_4(bulk->mppc_dec, pSrcData, SrcSize, flags, &roff, &rlen);
-			*ppDstData = (bulk->mppc_dec->history_buf + roff);
-			*pDstSize = rlen;
+			size = SrcSize;
+			mppc_decompress(bulk->mppcRecv, pSrcData, ppDstData, &size, flags);
+			*pDstSize = size;
+			status = 1;
+			printf("BulkDecompress: SrcSize: %d DstSize: %d Flags: 0x%04X\n", SrcSize, *pDstSize, flags);
 			break;
 
 		case PACKET_COMPR_TYPE_64K:
-			status = decompress_rdp_5(bulk->mppc_dec, pSrcData, SrcSize, flags, &roff, &rlen);
-			*ppDstData = (bulk->mppc_dec->history_buf + roff);
-			*pDstSize = rlen;
+			size = SrcSize;
+			mppc_decompress(bulk->mppcRecv, pSrcData, ppDstData, &size, flags);
+			*pDstSize = size;
+			status = 1;
 			printf("BulkDecompress: SrcSize: %d DstSize: %d Flags: 0x%04X\n", SrcSize, *pDstSize, flags);
 			break;