utility/efidecompress.c - mirrors/cros/chromiumos/platform/vboot_reference - Git at Google

 /* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 /*++

 Copyright (c) 2004 - 2006, Intel Corporation
 All rights reserved. This program and the accompanying materials
 are licensed and made available under the terms and conditions of the BSD License
 which accompanies this distribution.  The full text of the license may be found at
 http://opensource.org/licenses/bsd-license.php

 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

 Module Name:

   Decompress.c

 Abstract:

   Decompressor. Algorithm Ported from OPSD code (Decomp.asm)

 --*/

 #include <errno.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>

 #include "eficompress.h"


 //
 // Decompression algorithm begins here
 //
 #define BITBUFSIZ 32
 #define MAXMATCH  256
 #define THRESHOLD 3
 #define CODE_BIT  16
 #define BAD_TABLE - 1

 //
 // C: Char&Len Set; P: Position Set; T: exTra Set
 //
 #define NC      (0xff + MAXMATCH + 2 - THRESHOLD)
 #define CBIT    9
 #define MAXPBIT 5
 #define TBIT    5
 #define MAXNP   ((1U << MAXPBIT) - 1)
 #define NT      (CODE_BIT + 3)
 #if NT > MAXNP
 #define NPT NT
 #else
 #define NPT MAXNP
 #endif

 typedef struct {
   UINT8   *mSrcBase;  // Starting address of compressed data
   UINT8   *mDstBase;  // Starting address of decompressed data
   UINT32  mOutBuf;
   UINT32  mInBuf;

   UINT16  mBitCount;
   UINT32  mBitBuf;
   UINT32  mSubBitBuf;
   UINT16  mBlockSize;
   UINT32  mCompSize;
   UINT32  mOrigSize;

   UINT16  mBadTableFlag;

   UINT16  mLeft[2 * NC - 1];
   UINT16  mRight[2 * NC - 1];
   UINT8   mCLen[NC];
   UINT8   mPTLen[NPT];
   UINT16  mCTable[4096];
   UINT16  mPTTable[256];

   //
   // The length of the field 'Position Set Code Length Array Size' in Block Header.
   // For EFI 1.1 de/compression algorithm, mPBit = 4
   // For Tiano de/compression algorithm, mPBit = 5
   //
   UINT8   mPBit;
 } SCRATCH_DATA;

 STATIC
 VOID
 FillBuf (
   IN  SCRATCH_DATA  *Sd,
   IN  UINT16        NumOfBits
   )
 /*++

 Routine Description:

   Shift mBitBuf NumOfBits left. Read in NumOfBits of bits from source.

 Arguments:

   Sd        - The global scratch data
   NumOfBits  - The number of bits to shift and read.

 Returns: (VOID)

 --*/
 {
   Sd->mBitBuf = (UINT32) (Sd->mBitBuf << NumOfBits);

   while (NumOfBits > Sd->mBitCount) {

     Sd->mBitBuf |= (UINT32) (Sd->mSubBitBuf << (NumOfBits = (UINT16) (NumOfBits - Sd->mBitCount)));

     if (Sd->mCompSize > 0) {
       //
       // Get 1 byte into SubBitBuf
       //
       Sd->mCompSize--;
       Sd->mSubBitBuf  = 0;
       Sd->mSubBitBuf  = Sd->mSrcBase[Sd->mInBuf++];
       Sd->mBitCount   = 8;

     } else {
       //
       // No more bits from the source, just pad zero bit.
       //
       Sd->mSubBitBuf  = 0;
       Sd->mBitCount   = 8;

     }
   }

   Sd->mBitCount = (UINT16) (Sd->mBitCount - NumOfBits);
   Sd->mBitBuf |= Sd->mSubBitBuf >> Sd->mBitCount;
 }

 STATIC
 UINT32
 GetBits (
   IN  SCRATCH_DATA  *Sd,
   IN  UINT16        NumOfBits
   )
 /*++

 Routine Description:

   Get NumOfBits of bits out from mBitBuf. Fill mBitBuf with subsequent
   NumOfBits of bits from source. Returns NumOfBits of bits that are
   popped out.

 Arguments:

   Sd            - The global scratch data.
   NumOfBits     - The number of bits to pop and read.

 Returns:

   The bits that are popped out.

 --*/
 {
   UINT32  OutBits;

   OutBits = (UINT32) (Sd->mBitBuf >> (BITBUFSIZ - NumOfBits));

   FillBuf (Sd, NumOfBits);

   return OutBits;
 }

 STATIC
 UINT16
 MakeTable (
   IN  SCRATCH_DATA  *Sd,
   IN  UINT16        NumOfChar,
   IN  UINT8         *BitLen,
   IN  UINT16        TableBits,
   OUT UINT16        *Table
   )
 /*++

 Routine Description:

   Creates Huffman Code mapping table according to code length array.

 Arguments:

   Sd        - The global scratch data
   NumOfChar - Number of symbols in the symbol set
   BitLen    - Code length array
   TableBits - The width of the mapping table
   Table     - The table

 Returns:

   0         - OK.
   BAD_TABLE - The table is corrupted.

 --*/
 {
   UINT16  Count[17];
   UINT16  Weight[17];
   UINT16  Start[18];
   UINT16  *Pointer;
   UINT16  Index3;
   UINT16  Index;
   UINT16  Len;
   UINT16  Char;
   UINT16  JuBits;
   UINT16  Avail;
   UINT16  NextCode;
   UINT16  Mask;

   for (Index = 1; Index <= 16; Index++) {
     Count[Index] = 0;
   }

   for (Index = 0; Index < NumOfChar; Index++) {
     Count[BitLen[Index]]++;
   }

   Start[1] = 0;

   for (Index = 1; Index <= 16; Index++) {
     Start[Index + 1] = (UINT16) (Start[Index] + (Count[Index] << (16 - Index)));
   }

   if (Start[17] != 0) {
     /*(1U << 16)*/
     return (UINT16) BAD_TABLE;
   }

   JuBits = (UINT16) (16 - TableBits);

   for (Index = 1; Index <= TableBits; Index++) {
     Start[Index] >>= JuBits;
     Weight[Index] = (UINT16) (1U << (TableBits - Index));
   }

   while (Index <= 16) {
     Weight[Index] = (UINT16) (1U << (16 - Index));
     Index++;
   }

   Index = (UINT16) (Start[TableBits + 1] >> JuBits);

   if (Index != 0) {
     Index3 = (UINT16) (1U << TableBits);
     while (Index != Index3) {
       Table[Index++] = 0;
     }
   }

   Avail = NumOfChar;
   Mask  = (UINT16) (1U << (15 - TableBits));

   for (Char = 0; Char < NumOfChar; Char++) {

     Len = BitLen[Char];
     if (Len == 0) {
       continue;
     }

     NextCode = (UINT16) (Start[Len] + Weight[Len]);

     if (Len <= TableBits) {

       for (Index = Start[Len]; Index < NextCode; Index++) {
         Table[Index] = Char;
       }

     } else {

       Index3  = Start[Len];
       Pointer = &Table[Index3 >> JuBits];
       Index   = (UINT16) (Len - TableBits);

       while (Index != 0) {
         if (*Pointer == 0) {
           Sd->mRight[Avail]                     = Sd->mLeft[Avail] = 0;
           *Pointer = Avail++;
         }

         if (Index3 & Mask) {
           Pointer = &Sd->mRight[*Pointer];
         } else {
           Pointer = &Sd->mLeft[*Pointer];
         }

         Index3 <<= 1;
         Index--;
       }

       *Pointer = Char;

     }

     Start[Len] = NextCode;
   }
   //
   // Succeeds
   //
   return 0;
 }

 STATIC
 UINT32
 DecodeP (
   IN  SCRATCH_DATA  *Sd
   )
 /*++

 Routine Description:

   Decodes a position value.

 Arguments:

   Sd      - the global scratch data

 Returns:

   The position value decoded.

 --*/
 {
   UINT16  Val;
   UINT32  Mask;
   UINT32  Pos;

   Val = Sd->mPTTable[Sd->mBitBuf >> (BITBUFSIZ - 8)];

   if (Val >= MAXNP) {
     Mask = 1U << (BITBUFSIZ - 1 - 8);

     do {

       if (Sd->mBitBuf & Mask) {
         Val = Sd->mRight[Val];
       } else {
         Val = Sd->mLeft[Val];
       }

       Mask >>= 1;
     } while (Val >= MAXNP);
   }
   //
   // Advance what we have read
   //
   FillBuf (Sd, Sd->mPTLen[Val]);

   Pos = Val;
   if (Val > 1) {
     Pos = (UINT32) ((1U << (Val - 1)) + GetBits (Sd, (UINT16) (Val - 1)));
   }

   return Pos;
 }

 STATIC
 UINT16
 ReadPTLen (
   IN  SCRATCH_DATA  *Sd,
   IN  UINT16        nn,
   IN  UINT16        nbit,
   IN  UINT16        Special
   )
 /*++

 Routine Description:

   Reads code lengths for the Extra Set or the Position Set

 Arguments:

   Sd        - The global scratch data
   nn        - Number of symbols
   nbit      - Number of bits needed to represent nn
   Special   - The special symbol that needs to be taken care of

 Returns:

   0         - OK.
   BAD_TABLE - Table is corrupted.

 --*/
 {
   UINT16  Number;
   UINT16  CharC;
   UINT16  Index;
   UINT32  Mask;

   Number = (UINT16) GetBits (Sd, nbit);

   if (Number == 0) {
     CharC = (UINT16) GetBits (Sd, nbit);

     for (Index = 0; Index < 256; Index++) {
       Sd->mPTTable[Index] = CharC;
     }

     for (Index = 0; Index < nn; Index++) {
       Sd->mPTLen[Index] = 0;
     }

     return 0;
   }

   Index = 0;

   while (Index < Number) {

     CharC = (UINT16) (Sd->mBitBuf >> (BITBUFSIZ - 3));

     if (CharC == 7) {
       Mask = 1U << (BITBUFSIZ - 1 - 3);
       while (Mask & Sd->mBitBuf) {
         Mask >>= 1;
         CharC += 1;
       }
     }

     FillBuf (Sd, (UINT16) ((CharC < 7) ? 3 : CharC - 3));

     Sd->mPTLen[Index++] = (UINT8) CharC;

     if (Index == Special) {
       CharC = (UINT16) GetBits (Sd, 2);
       while ((INT16) (--CharC) >= 0) {
         Sd->mPTLen[Index++] = 0;
       }
     }
   }

   while (Index < nn) {
     Sd->mPTLen[Index++] = 0;
   }

   return MakeTable (Sd, nn, Sd->mPTLen, 8, Sd->mPTTable);
 }

 STATIC
 VOID
 ReadCLen (
   SCRATCH_DATA  *Sd
   )
 /*++

 Routine Description:

   Reads code lengths for Char&Len Set.

 Arguments:

   Sd    - the global scratch data

 Returns: (VOID)

 --*/
 {
   UINT16  Number;
   UINT16  CharC;
   UINT16  Index;
   UINT32  Mask;

   Number = (UINT16) GetBits (Sd, CBIT);

   if (Number == 0) {
     CharC = (UINT16) GetBits (Sd, CBIT);

     for (Index = 0; Index < NC; Index++) {
       Sd->mCLen[Index] = 0;
     }

     for (Index = 0; Index < 4096; Index++) {
       Sd->mCTable[Index] = CharC;
     }

     return ;
   }

   Index = 0;
   while (Index < Number) {

     CharC = Sd->mPTTable[Sd->mBitBuf >> (BITBUFSIZ - 8)];
     if (CharC >= NT) {
       Mask = 1U << (BITBUFSIZ - 1 - 8);

       do {

         if (Mask & Sd->mBitBuf) {
           CharC = Sd->mRight[CharC];
         } else {
           CharC = Sd->mLeft[CharC];
         }

         Mask >>= 1;

       } while (CharC >= NT);
     }
     //
     // Advance what we have read
     //
     FillBuf (Sd, Sd->mPTLen[CharC]);

     if (CharC <= 2) {

       if (CharC == 0) {
         CharC = 1;
       } else if (CharC == 1) {
         CharC = (UINT16) (GetBits (Sd, 4) + 3);
       } else if (CharC == 2) {
         CharC = (UINT16) (GetBits (Sd, CBIT) + 20);
       }

       while ((INT16) (--CharC) >= 0) {
         Sd->mCLen[Index++] = 0;
       }

     } else {

       Sd->mCLen[Index++] = (UINT8) (CharC - 2);

     }
   }

   while (Index < NC) {
     Sd->mCLen[Index++] = 0;
   }

   MakeTable (Sd, NC, Sd->mCLen, 12, Sd->mCTable);

   return ;
 }

 STATIC
 UINT16
 DecodeC (
   SCRATCH_DATA  *Sd
   )
 /*++

 Routine Description:

   Decode a character/length value.

 Arguments:

   Sd    - The global scratch data.

 Returns:

   The value decoded.

 --*/
 {
   UINT16  Index2;
   UINT32  Mask;

   if (Sd->mBlockSize == 0) {
     //
     // Starting a new block
     //
     Sd->mBlockSize    = (UINT16) GetBits (Sd, 16);
     Sd->mBadTableFlag = ReadPTLen (Sd, NT, TBIT, 3);
     if (Sd->mBadTableFlag != 0) {
       return 0;
     }

     ReadCLen (Sd);

     Sd->mBadTableFlag = ReadPTLen (Sd, MAXNP, Sd->mPBit, (UINT16) (-1));
     if (Sd->mBadTableFlag != 0) {
       return 0;
     }
   }

   Sd->mBlockSize--;
   Index2 = Sd->mCTable[Sd->mBitBuf >> (BITBUFSIZ - 12)];

   if (Index2 >= NC) {
     Mask = 1U << (BITBUFSIZ - 1 - 12);

     do {
       if (Sd->mBitBuf & Mask) {
         Index2 = Sd->mRight[Index2];
       } else {
         Index2 = Sd->mLeft[Index2];
       }

       Mask >>= 1;
     } while (Index2 >= NC);
   }
   //
   // Advance what we have read
   //
   FillBuf (Sd, Sd->mCLen[Index2]);

   return Index2;
 }

 STATIC
 VOID
 Decode (
   SCRATCH_DATA  *Sd
   )
 /*++

 Routine Description:

   Decode the source data and put the resulting data into the destination buffer.

 Arguments:

   Sd            - The global scratch data

 Returns: (VOID)

  --*/
 {
   UINT16  BytesRemain;
   UINT32  DataIdx;
   UINT16  CharC;

   BytesRemain = (UINT16) (-1);

   DataIdx     = 0;

   for (;;) {
     CharC = DecodeC (Sd);
     if (Sd->mBadTableFlag != 0) {
       return ;
     }

     if (CharC < 256) {
       //
       // Process an Original character
       //
       if (Sd->mOutBuf >= Sd->mOrigSize) {
         return ;
       } else {
         Sd->mDstBase[Sd->mOutBuf++] = (UINT8) CharC;
       }

     } else {
       //
       // Process a Pointer
       //
       CharC       = (UINT16) (CharC - (UINT8_MAX + 1 - THRESHOLD));

       BytesRemain = CharC;

       DataIdx     = Sd->mOutBuf - DecodeP (Sd) - 1;

       BytesRemain--;
       while ((INT16) (BytesRemain) >= 0) {
         Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];
         if (Sd->mOutBuf >= Sd->mOrigSize) {
           return ;
         }

         BytesRemain--;
       }
     }
   }

   return ;
 }

 EFI_STATUS
 GetInfo (
   IN      VOID    *Source,
   IN      UINT32  SrcSize,
   OUT     UINT32  *DstSize,
   OUT     UINT32  *ScratchSize
   )
 /*++

 Routine Description:

   The internal implementation of *_DECOMPRESS_PROTOCOL.GetInfo().

 Arguments:

   Source      - The source buffer containing the compressed data.
   SrcSize     - The size of source buffer
   DstSize     - The size of destination buffer.
   ScratchSize - The size of scratch buffer.

 Returns:

   EFI_SUCCESS           - The size of destination buffer and the size of scratch buffer are successull retrieved.
   EFI_INVALID_PARAMETER - The source data is corrupted

 --*/
 {
   UINT8 *Src;

   *ScratchSize  = sizeof (SCRATCH_DATA);

   Src           = Source;
   if (SrcSize < 8) {
     return EFI_INVALID_PARAMETER;
   }

   *DstSize = Src[4] + (Src[5] << 8) + (Src[6] << 16) + (Src[7] << 24);
   return EFI_SUCCESS;
 }

 EFI_STATUS
 Decompress (
   IN      VOID    *Source,
   IN      UINT32  SrcSize,
   IN OUT  VOID    *Destination,
   IN      UINT32  DstSize,
   IN OUT  VOID    *Scratch,
   IN      UINT32  ScratchSize,
   IN      UINT8   Version
   )
 /*++

 Routine Description:

   The internal implementation of *_DECOMPRESS_PROTOCOL.Decompress().

 Arguments:

   Source      - The source buffer containing the compressed data.
   SrcSize     - The size of source buffer
   Destination - The destination buffer to store the decompressed data
   DstSize     - The size of destination buffer.
   Scratch     - The buffer used internally by the decompress routine. This  buffer is needed to store intermediate data.
   ScratchSize - The size of scratch buffer.
   Version     - The version of de/compression algorithm.
                 Version 1 for EFI 1.1 de/compression algorithm.
                 Version 2 for Tiano de/compression algorithm.

 Returns:

   EFI_SUCCESS           - Decompression is successfull
   EFI_INVALID_PARAMETER - The source data is corrupted

 --*/
 {
   UINT32        Index;
   UINT32        CompSize;
   UINT32        OrigSize;
   EFI_STATUS    Status;
   SCRATCH_DATA  *Sd;
   UINT8         *Src;
   UINT8         *Dst;

   Status  = EFI_SUCCESS;
   Src     = Source;
   Dst     = Destination;

   if (ScratchSize < sizeof (SCRATCH_DATA)) {
     return EFI_INVALID_PARAMETER;
   }

   Sd = (SCRATCH_DATA *) Scratch;

   if (SrcSize < 8) {
     return EFI_INVALID_PARAMETER;
   }

   CompSize  = Src[0] + (Src[1] << 8) + (Src[2] << 16) + (Src[3] << 24);
   OrigSize  = Src[4] + (Src[5] << 8) + (Src[6] << 16) + (Src[7] << 24);

   //
   // If compressed file size is 0, return
   //
   if (OrigSize == 0) {
     return Status;
   }

   if (SrcSize < CompSize + 8) {
     return EFI_INVALID_PARAMETER;
   }

   if (DstSize != OrigSize) {
     return EFI_INVALID_PARAMETER;
   }

   Src = Src + 8;

   for (Index = 0; Index < sizeof (SCRATCH_DATA); Index++) {
     ((UINT8 *) Sd)[Index] = 0;
   }
   //
   // The length of the field 'Position Set Code Length Array Size' in Block Header.
   // For EFI 1.1 de/compression algorithm(Version 1), mPBit = 4
   // For Tiano de/compression algorithm(Version 2), mPBit = 5
   //
   switch (Version) {
   case 1:
     Sd->mPBit = 4;
     break;

   case 2:
     Sd->mPBit = 5;
     break;

   default:
     //
     // Currently, only have 2 versions
     //
     return EFI_INVALID_PARAMETER;
   }

   Sd->mSrcBase  = Src;
   Sd->mDstBase  = Dst;
   Sd->mCompSize = CompSize;
   Sd->mOrigSize = OrigSize;

   //
   // Fill the first BITBUFSIZ bits
   //
   FillBuf (Sd, BITBUFSIZ);

   //
   // Decompress it
   //
   Decode (Sd);

   if (Sd->mBadTableFlag != 0) {
     //
     // Something wrong with the source
     //
     Status = EFI_INVALID_PARAMETER;
   }

   return Status;
 }

 EFI_STATUS
 EFIAPI
 EfiGetInfo (
   IN      VOID                    *Source,
   IN      UINT32                  SrcSize,
   OUT     UINT32                  *DstSize,
   OUT     UINT32                  *ScratchSize
   )
 /*++

 Routine Description:

   The implementation is same as that  of EFI_DECOMPRESS_PROTOCOL.GetInfo().

 Arguments:

   This        - The protocol instance pointer
   Source      - The source buffer containing the compressed data.
   SrcSize     - The size of source buffer
   DstSize     - The size of destination buffer.
   ScratchSize - The size of scratch buffer.

 Returns:

   EFI_SUCCESS           - The size of destination buffer and the size of scratch buffer are successull retrieved.
   EFI_INVALID_PARAMETER - The source data is corrupted

 --*/
 {
   return GetInfo (
           Source,
           SrcSize,
           DstSize,
           ScratchSize
           );
 }

 EFI_STATUS
 EFIAPI
 EfiDecompress (
   IN      VOID                    *Source,
   IN      UINT32                  SrcSize,
   IN OUT  VOID                    *Destination,
   IN      UINT32                  DstSize,
   IN OUT  VOID                    *Scratch,
   IN      UINT32                  ScratchSize
   )
 /*++

 Routine Description:

   The implementation is same as that of EFI_DECOMPRESS_PROTOCOL.Decompress().

 Arguments:

   This        - The protocol instance pointer
   Source      - The source buffer containing the compressed data.
   SrcSize     - The size of source buffer
   Destination - The destination buffer to store the decompressed data
   DstSize     - The size of destination buffer.
   Scratch     - The buffer used internally by the decompress routine. This  buffer is needed to store intermediate data.
   ScratchSize - The size of scratch buffer.

 Returns:

   EFI_SUCCESS           - Decompression is successfull
   EFI_INVALID_PARAMETER - The source data is corrupted

 --*/
 {
   //
   // For EFI 1.1 de/compression algorithm, the version is 1.
   //
   return Decompress (
           Source,
           SrcSize,
           Destination,
           DstSize,
           Scratch,
           ScratchSize,
           1
           );
 }

 EFI_STATUS
 EFIAPI
 TianoGetInfo (
   IN      VOID                          *Source,
   IN      UINT32                        SrcSize,
   OUT     UINT32                        *DstSize,
   OUT     UINT32                        *ScratchSize
   )
 /*++

 Routine Description:

   The implementation is same as that of EFI_TIANO_DECOMPRESS_PROTOCOL.GetInfo().

 Arguments:

   This        - The protocol instance pointer
   Source      - The source buffer containing the compressed data.
   SrcSize     - The size of source buffer
   DstSize     - The size of destination buffer.
   ScratchSize - The size of scratch buffer.

 Returns:

   EFI_SUCCESS           - The size of destination buffer and the size of scratch buffer are successull retrieved.
   EFI_INVALID_PARAMETER - The source data is corrupted

 --*/
 {
   return GetInfo (
           Source,
           SrcSize,
           DstSize,
           ScratchSize
           );
 }

 EFI_STATUS
 EFIAPI
 TianoDecompress (
   IN      VOID                          *Source,
   IN      UINT32                        SrcSize,
   IN OUT  VOID                          *Destination,
   IN      UINT32                        DstSize,
   IN OUT  VOID                          *Scratch,
   IN      UINT32                        ScratchSize
   )
 /*++

 Routine Description:

   The implementation is same as that  of EFI_TIANO_DECOMPRESS_PROTOCOL.Decompress().

 Arguments:

   This        - The protocol instance pointer
   Source      - The source buffer containing the compressed data.
   SrcSize     - The size of source buffer
   Destination - The destination buffer to store the decompressed data
   DstSize     - The size of destination buffer.
   Scratch     - The buffer used internally by the decompress routine. This  buffer is needed to store intermediate data.
   ScratchSize - The size of scratch buffer.

 Returns:

   EFI_SUCCESS           - Decompression is successfull
   EFI_INVALID_PARAMETER - The source data is corrupted

 --*/
 {
   //
   // For Tiano de/compression algorithm, the version is 2.
   //
   return Decompress (
           Source,
           SrcSize,
           Destination,
           DstSize,
           Scratch,
           ScratchSize,
           2
           );
 }
	/* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	/*++

	Copyright (c) 2004 - 2006, Intel Corporation
	All rights reserved. This program and the accompanying materials
	are licensed and made available under the terms and conditions of the BSD License
	which accompanies this distribution. The full text of the license may be found at
	http://opensource.org/licenses/bsd-license.php

	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

	Module Name:

	Decompress.c

	Abstract:

	Decompressor. Algorithm Ported from OPSD code (Decomp.asm)

	--*/

	#include <errno.h>
	#include <stdint.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <unistd.h>

	#include "eficompress.h"


	//
	// Decompression algorithm begins here
	//
	#define BITBUFSIZ 32
	#define MAXMATCH 256
	#define THRESHOLD 3
	#define CODE_BIT 16
	#define BAD_TABLE - 1

	//
	// C: Char&Len Set; P: Position Set; T: exTra Set
	//
	#define NC (0xff + MAXMATCH + 2 - THRESHOLD)
	#define CBIT 9
	#define MAXPBIT 5
	#define TBIT 5
	#define MAXNP ((1U << MAXPBIT) - 1)
	#define NT (CODE_BIT + 3)
	#if NT > MAXNP
	#define NPT NT
	#else
	#define NPT MAXNP
	#endif

	typedef struct {
	UINT8 *mSrcBase; // Starting address of compressed data
	UINT8 *mDstBase; // Starting address of decompressed data
	UINT32 mOutBuf;
	UINT32 mInBuf;

	UINT16 mBitCount;
	UINT32 mBitBuf;
	UINT32 mSubBitBuf;
	UINT16 mBlockSize;
	UINT32 mCompSize;
	UINT32 mOrigSize;

	UINT16 mBadTableFlag;

	UINT16 mLeft[2 * NC - 1];
	UINT16 mRight[2 * NC - 1];
	UINT8 mCLen[NC];
	UINT8 mPTLen[NPT];
	UINT16 mCTable[4096];
	UINT16 mPTTable[256];

	//
	// The length of the field 'Position Set Code Length Array Size' in Block Header.
	// For EFI 1.1 de/compression algorithm, mPBit = 4
	// For Tiano de/compression algorithm, mPBit = 5
	//
	UINT8 mPBit;
	} SCRATCH_DATA;

	STATIC
	VOID
	FillBuf (
	IN SCRATCH_DATA *Sd,
	IN UINT16 NumOfBits
	)
	/*++

	Routine Description:

	Shift mBitBuf NumOfBits left. Read in NumOfBits of bits from source.

	Arguments:

	Sd - The global scratch data
	NumOfBits - The number of bits to shift and read.

	Returns: (VOID)

	--*/
	{
	Sd->mBitBuf = (UINT32) (Sd->mBitBuf << NumOfBits);

	while (NumOfBits > Sd->mBitCount) {

	Sd->mBitBuf \|= (UINT32) (Sd->mSubBitBuf << (NumOfBits = (UINT16) (NumOfBits - Sd->mBitCount)));

	if (Sd->mCompSize > 0) {
	//
	// Get 1 byte into SubBitBuf
	//
	Sd->mCompSize--;
	Sd->mSubBitBuf = 0;
	Sd->mSubBitBuf = Sd->mSrcBase[Sd->mInBuf++];
	Sd->mBitCount = 8;

	} else {
	//
	// No more bits from the source, just pad zero bit.
	//
	Sd->mSubBitBuf = 0;
	Sd->mBitCount = 8;

	}
	}

	Sd->mBitCount = (UINT16) (Sd->mBitCount - NumOfBits);
	Sd->mBitBuf \|= Sd->mSubBitBuf >> Sd->mBitCount;
	}

	STATIC
	UINT32
	GetBits (
	IN SCRATCH_DATA *Sd,
	IN UINT16 NumOfBits
	)
	/*++

	Routine Description:

	Get NumOfBits of bits out from mBitBuf. Fill mBitBuf with subsequent
	NumOfBits of bits from source. Returns NumOfBits of bits that are
	popped out.

	Arguments:

	Sd - The global scratch data.
	NumOfBits - The number of bits to pop and read.

	Returns:

	The bits that are popped out.

	--*/
	{
	UINT32 OutBits;

	OutBits = (UINT32) (Sd->mBitBuf >> (BITBUFSIZ - NumOfBits));

	FillBuf (Sd, NumOfBits);

	return OutBits;
	}

	STATIC
	UINT16
	MakeTable (
	IN SCRATCH_DATA *Sd,
	IN UINT16 NumOfChar,
	IN UINT8 *BitLen,
	IN UINT16 TableBits,
	OUT UINT16 *Table
	)
	/*++

	Routine Description:

	Creates Huffman Code mapping table according to code length array.

	Arguments:

	Sd - The global scratch data
	NumOfChar - Number of symbols in the symbol set
	BitLen - Code length array
	TableBits - The width of the mapping table
	Table - The table

	Returns:

	0 - OK.
	BAD_TABLE - The table is corrupted.

	--*/
	{
	UINT16 Count[17];
	UINT16 Weight[17];
	UINT16 Start[18];
	UINT16 *Pointer;
	UINT16 Index3;
	UINT16 Index;
	UINT16 Len;
	UINT16 Char;
	UINT16 JuBits;
	UINT16 Avail;
	UINT16 NextCode;
	UINT16 Mask;

	for (Index = 1; Index <= 16; Index++) {
	Count[Index] = 0;
	}

	for (Index = 0; Index < NumOfChar; Index++) {
	Count[BitLen[Index]]++;
	}

	Start[1] = 0;

	for (Index = 1; Index <= 16; Index++) {
	Start[Index + 1] = (UINT16) (Start[Index] + (Count[Index] << (16 - Index)));
	}

	if (Start[17] != 0) {
	/(1U << 16)/
	return (UINT16) BAD_TABLE;
	}

	JuBits = (UINT16) (16 - TableBits);

	for (Index = 1; Index <= TableBits; Index++) {
	Start[Index] >>= JuBits;
	Weight[Index] = (UINT16) (1U << (TableBits - Index));
	}

	while (Index <= 16) {
	Weight[Index] = (UINT16) (1U << (16 - Index));
	Index++;
	}

	Index = (UINT16) (Start[TableBits + 1] >> JuBits);

	if (Index != 0) {
	Index3 = (UINT16) (1U << TableBits);
	while (Index != Index3) {
	Table[Index++] = 0;
	}
	}

	Avail = NumOfChar;
	Mask = (UINT16) (1U << (15 - TableBits));

	for (Char = 0; Char < NumOfChar; Char++) {

	Len = BitLen[Char];
	if (Len == 0) {
	continue;
	}

	NextCode = (UINT16) (Start[Len] + Weight[Len]);

	if (Len <= TableBits) {

	for (Index = Start[Len]; Index < NextCode; Index++) {
	Table[Index] = Char;
	}

	} else {

	Index3 = Start[Len];
	Pointer = &Table[Index3 >> JuBits];
	Index = (UINT16) (Len - TableBits);

	while (Index != 0) {
	if (*Pointer == 0) {
	Sd->mRight[Avail] = Sd->mLeft[Avail] = 0;
	*Pointer = Avail++;
	}

	if (Index3 & Mask) {
	Pointer = &Sd->mRight[*Pointer];
	} else {
	Pointer = &Sd->mLeft[*Pointer];
	}

	Index3 <<= 1;
	Index--;
	}

	*Pointer = Char;

	}

	Start[Len] = NextCode;
	}
	//
	// Succeeds
	//
	return 0;
	}

	STATIC
	UINT32
	DecodeP (
	IN SCRATCH_DATA *Sd
	)
	/*++

	Routine Description:

	Decodes a position value.

	Arguments:

	Sd - the global scratch data

	Returns:

	The position value decoded.

	--*/
	{
	UINT16 Val;
	UINT32 Mask;
	UINT32 Pos;

	Val = Sd->mPTTable[Sd->mBitBuf >> (BITBUFSIZ - 8)];

	if (Val >= MAXNP) {
	Mask = 1U << (BITBUFSIZ - 1 - 8);

	do {

	if (Sd->mBitBuf & Mask) {
	Val = Sd->mRight[Val];
	} else {
	Val = Sd->mLeft[Val];
	}

	Mask >>= 1;
	} while (Val >= MAXNP);
	}
	//
	// Advance what we have read
	//
	FillBuf (Sd, Sd->mPTLen[Val]);

	Pos = Val;
	if (Val > 1) {
	Pos = (UINT32) ((1U << (Val - 1)) + GetBits (Sd, (UINT16) (Val - 1)));
	}

	return Pos;
	}

	STATIC
	UINT16
	ReadPTLen (
	IN SCRATCH_DATA *Sd,
	IN UINT16 nn,
	IN UINT16 nbit,
	IN UINT16 Special
	)
	/*++

	Routine Description:

	Reads code lengths for the Extra Set or the Position Set

	Arguments:

	Sd - The global scratch data
	nn - Number of symbols
	nbit - Number of bits needed to represent nn
	Special - The special symbol that needs to be taken care of

	Returns:

	0 - OK.
	BAD_TABLE - Table is corrupted.

	--*/
	{
	UINT16 Number;
	UINT16 CharC;
	UINT16 Index;
	UINT32 Mask;

	Number = (UINT16) GetBits (Sd, nbit);

	if (Number == 0) {
	CharC = (UINT16) GetBits (Sd, nbit);

	for (Index = 0; Index < 256; Index++) {
	Sd->mPTTable[Index] = CharC;
	}

	for (Index = 0; Index < nn; Index++) {
	Sd->mPTLen[Index] = 0;
	}

	return 0;
	}

	Index = 0;

	while (Index < Number) {

	CharC = (UINT16) (Sd->mBitBuf >> (BITBUFSIZ - 3));

	if (CharC == 7) {
	Mask = 1U << (BITBUFSIZ - 1 - 3);
	while (Mask & Sd->mBitBuf) {
	Mask >>= 1;
	CharC += 1;
	}
	}

	FillBuf (Sd, (UINT16) ((CharC < 7) ? 3 : CharC - 3));

	Sd->mPTLen[Index++] = (UINT8) CharC;

	if (Index == Special) {
	CharC = (UINT16) GetBits (Sd, 2);
	while ((INT16) (--CharC) >= 0) {
	Sd->mPTLen[Index++] = 0;
	}
	}
	}

	while (Index < nn) {
	Sd->mPTLen[Index++] = 0;
	}

	return MakeTable (Sd, nn, Sd->mPTLen, 8, Sd->mPTTable);
	}

	STATIC
	VOID
	ReadCLen (
	SCRATCH_DATA *Sd
	)
	/*++

	Routine Description:

	Reads code lengths for Char&Len Set.

	Arguments:

	Sd - the global scratch data

	Returns: (VOID)

	--*/
	{
	UINT16 Number;
	UINT16 CharC;
	UINT16 Index;
	UINT32 Mask;

	Number = (UINT16) GetBits (Sd, CBIT);

	if (Number == 0) {
	CharC = (UINT16) GetBits (Sd, CBIT);

	for (Index = 0; Index < NC; Index++) {
	Sd->mCLen[Index] = 0;
	}

	for (Index = 0; Index < 4096; Index++) {
	Sd->mCTable[Index] = CharC;
	}

	return ;
	}

	Index = 0;
	while (Index < Number) {

	CharC = Sd->mPTTable[Sd->mBitBuf >> (BITBUFSIZ - 8)];
	if (CharC >= NT) {
	Mask = 1U << (BITBUFSIZ - 1 - 8);

	do {

	if (Mask & Sd->mBitBuf) {
	CharC = Sd->mRight[CharC];
	} else {
	CharC = Sd->mLeft[CharC];
	}

	Mask >>= 1;

	} while (CharC >= NT);
	}
	//
	// Advance what we have read
	//
	FillBuf (Sd, Sd->mPTLen[CharC]);

	if (CharC <= 2) {

	if (CharC == 0) {
	CharC = 1;
	} else if (CharC == 1) {
	CharC = (UINT16) (GetBits (Sd, 4) + 3);
	} else if (CharC == 2) {
	CharC = (UINT16) (GetBits (Sd, CBIT) + 20);
	}

	while ((INT16) (--CharC) >= 0) {
	Sd->mCLen[Index++] = 0;
	}

	} else {

	Sd->mCLen[Index++] = (UINT8) (CharC - 2);

	}
	}

	while (Index < NC) {
	Sd->mCLen[Index++] = 0;
	}

	MakeTable (Sd, NC, Sd->mCLen, 12, Sd->mCTable);

	return ;
	}

	STATIC
	UINT16
	DecodeC (
	SCRATCH_DATA *Sd
	)
	/*++

	Routine Description:

	Decode a character/length value.

	Arguments:

	Sd - The global scratch data.

	Returns:

	The value decoded.

	--*/
	{
	UINT16 Index2;
	UINT32 Mask;

	if (Sd->mBlockSize == 0) {
	//
	// Starting a new block
	//
	Sd->mBlockSize = (UINT16) GetBits (Sd, 16);
	Sd->mBadTableFlag = ReadPTLen (Sd, NT, TBIT, 3);
	if (Sd->mBadTableFlag != 0) {
	return 0;
	}

	ReadCLen (Sd);

	Sd->mBadTableFlag = ReadPTLen (Sd, MAXNP, Sd->mPBit, (UINT16) (-1));
	if (Sd->mBadTableFlag != 0) {
	return 0;
	}
	}

	Sd->mBlockSize--;
	Index2 = Sd->mCTable[Sd->mBitBuf >> (BITBUFSIZ - 12)];

	if (Index2 >= NC) {
	Mask = 1U << (BITBUFSIZ - 1 - 12);

	do {
	if (Sd->mBitBuf & Mask) {
	Index2 = Sd->mRight[Index2];
	} else {
	Index2 = Sd->mLeft[Index2];
	}

	Mask >>= 1;
	} while (Index2 >= NC);
	}
	//
	// Advance what we have read
	//
	FillBuf (Sd, Sd->mCLen[Index2]);

	return Index2;
	}

	STATIC
	VOID
	Decode (
	SCRATCH_DATA *Sd
	)
	/*++

	Routine Description:

	Decode the source data and put the resulting data into the destination buffer.

	Arguments:

	Sd - The global scratch data

	Returns: (VOID)

	--*/
	{
	UINT16 BytesRemain;
	UINT32 DataIdx;
	UINT16 CharC;

	BytesRemain = (UINT16) (-1);

	DataIdx = 0;

	for (;;) {
	CharC = DecodeC (Sd);
	if (Sd->mBadTableFlag != 0) {
	return ;
	}

	if (CharC < 256) {
	//
	// Process an Original character
	//
	if (Sd->mOutBuf >= Sd->mOrigSize) {
	return ;
	} else {
	Sd->mDstBase[Sd->mOutBuf++] = (UINT8) CharC;
	}

	} else {
	//
	// Process a Pointer
	//
	CharC = (UINT16) (CharC - (UINT8_MAX + 1 - THRESHOLD));

	BytesRemain = CharC;

	DataIdx = Sd->mOutBuf - DecodeP (Sd) - 1;

	BytesRemain--;
	while ((INT16) (BytesRemain) >= 0) {
	Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];
	if (Sd->mOutBuf >= Sd->mOrigSize) {
	return ;
	}

	BytesRemain--;
	}
	}
	}

	return ;
	}

	EFI_STATUS
	GetInfo (
	IN VOID *Source,
	IN UINT32 SrcSize,
	OUT UINT32 *DstSize,
	OUT UINT32 *ScratchSize
	)
	/*++

	Routine Description:

	The internal implementation of *_DECOMPRESS_PROTOCOL.GetInfo().

	Arguments:

	Source - The source buffer containing the compressed data.
	SrcSize - The size of source buffer
	DstSize - The size of destination buffer.
	ScratchSize - The size of scratch buffer.

	Returns:

	EFI_SUCCESS - The size of destination buffer and the size of scratch buffer are successull retrieved.
	EFI_INVALID_PARAMETER - The source data is corrupted

	--*/
	{
	UINT8 *Src;

	*ScratchSize = sizeof (SCRATCH_DATA);

	Src = Source;
	if (SrcSize < 8) {
	return EFI_INVALID_PARAMETER;
	}

	*DstSize = Src[4] + (Src[5] << 8) + (Src[6] << 16) + (Src[7] << 24);
	return EFI_SUCCESS;
	}

	EFI_STATUS
	Decompress (
	IN VOID *Source,
	IN UINT32 SrcSize,
	IN OUT VOID *Destination,
	IN UINT32 DstSize,
	IN OUT VOID *Scratch,
	IN UINT32 ScratchSize,
	IN UINT8 Version
	)
	/*++

	Routine Description:

	The internal implementation of *_DECOMPRESS_PROTOCOL.Decompress().

	Arguments:

	Source - The source buffer containing the compressed data.
	SrcSize - The size of source buffer
	Destination - The destination buffer to store the decompressed data
	DstSize - The size of destination buffer.
	Scratch - The buffer used internally by the decompress routine. This buffer is needed to store intermediate data.
	ScratchSize - The size of scratch buffer.
	Version - The version of de/compression algorithm.
	Version 1 for EFI 1.1 de/compression algorithm.
	Version 2 for Tiano de/compression algorithm.

	Returns:

	EFI_SUCCESS - Decompression is successfull
	EFI_INVALID_PARAMETER - The source data is corrupted

	--*/
	{
	UINT32 Index;
	UINT32 CompSize;
	UINT32 OrigSize;
	EFI_STATUS Status;
	SCRATCH_DATA *Sd;
	UINT8 *Src;
	UINT8 *Dst;

	Status = EFI_SUCCESS;
	Src = Source;
	Dst = Destination;

	if (ScratchSize < sizeof (SCRATCH_DATA)) {
	return EFI_INVALID_PARAMETER;
	}

	Sd = (SCRATCH_DATA *) Scratch;

	if (SrcSize < 8) {
	return EFI_INVALID_PARAMETER;
	}

	CompSize = Src[0] + (Src[1] << 8) + (Src[2] << 16) + (Src[3] << 24);
	OrigSize = Src[4] + (Src[5] << 8) + (Src[6] << 16) + (Src[7] << 24);

	//
	// If compressed file size is 0, return
	//
	if (OrigSize == 0) {
	return Status;
	}

	if (SrcSize < CompSize + 8) {
	return EFI_INVALID_PARAMETER;
	}

	if (DstSize != OrigSize) {
	return EFI_INVALID_PARAMETER;
	}

	Src = Src + 8;

	for (Index = 0; Index < sizeof (SCRATCH_DATA); Index++) {
	((UINT8 *) Sd)[Index] = 0;
	}
	//
	// The length of the field 'Position Set Code Length Array Size' in Block Header.
	// For EFI 1.1 de/compression algorithm(Version 1), mPBit = 4
	// For Tiano de/compression algorithm(Version 2), mPBit = 5
	//
	switch (Version) {
	case 1:
	Sd->mPBit = 4;
	break;

	case 2:
	Sd->mPBit = 5;
	break;

	default:
	//
	// Currently, only have 2 versions
	//
	return EFI_INVALID_PARAMETER;
	}

	Sd->mSrcBase = Src;
	Sd->mDstBase = Dst;
	Sd->mCompSize = CompSize;
	Sd->mOrigSize = OrigSize;

	//
	// Fill the first BITBUFSIZ bits
	//
	FillBuf (Sd, BITBUFSIZ);

	//
	// Decompress it
	//
	Decode (Sd);

	if (Sd->mBadTableFlag != 0) {
	//
	// Something wrong with the source
	//
	Status = EFI_INVALID_PARAMETER;
	}

	return Status;
	}

	EFI_STATUS
	EFIAPI
	EfiGetInfo (
	IN VOID *Source,
	IN UINT32 SrcSize,
	OUT UINT32 *DstSize,
	OUT UINT32 *ScratchSize
	)
	/*++

	Routine Description:

	The implementation is same as that of EFI_DECOMPRESS_PROTOCOL.GetInfo().

	Arguments:

	This - The protocol instance pointer
	Source - The source buffer containing the compressed data.
	SrcSize - The size of source buffer
	DstSize - The size of destination buffer.
	ScratchSize - The size of scratch buffer.

	Returns:

	EFI_SUCCESS - The size of destination buffer and the size of scratch buffer are successull retrieved.
	EFI_INVALID_PARAMETER - The source data is corrupted

	--*/
	{
	return GetInfo (
	Source,
	SrcSize,
	DstSize,
	ScratchSize
	);
	}

	EFI_STATUS
	EFIAPI
	EfiDecompress (
	IN VOID *Source,
	IN UINT32 SrcSize,
	IN OUT VOID *Destination,
	IN UINT32 DstSize,
	IN OUT VOID *Scratch,
	IN UINT32 ScratchSize
	)
	/*++

	Routine Description:

	The implementation is same as that of EFI_DECOMPRESS_PROTOCOL.Decompress().

	Arguments:

	This - The protocol instance pointer
	Source - The source buffer containing the compressed data.
	SrcSize - The size of source buffer
	Destination - The destination buffer to store the decompressed data
	DstSize - The size of destination buffer.
	Scratch - The buffer used internally by the decompress routine. This buffer is needed to store intermediate data.
	ScratchSize - The size of scratch buffer.

	Returns:

	EFI_SUCCESS - Decompression is successfull
	EFI_INVALID_PARAMETER - The source data is corrupted

	--*/
	{
	//
	// For EFI 1.1 de/compression algorithm, the version is 1.
	//
	return Decompress (
	Source,
	SrcSize,
	Destination,
	DstSize,
	Scratch,
	ScratchSize,
	1
	);
	}

	EFI_STATUS
	EFIAPI
	TianoGetInfo (
	IN VOID *Source,
	IN UINT32 SrcSize,
	OUT UINT32 *DstSize,
	OUT UINT32 *ScratchSize
	)
	/*++

	Routine Description:

	The implementation is same as that of EFI_TIANO_DECOMPRESS_PROTOCOL.GetInfo().

	Arguments:

	This - The protocol instance pointer
	Source - The source buffer containing the compressed data.
	SrcSize - The size of source buffer
	DstSize - The size of destination buffer.
	ScratchSize - The size of scratch buffer.

	Returns:

	EFI_SUCCESS - The size of destination buffer and the size of scratch buffer are successull retrieved.
	EFI_INVALID_PARAMETER - The source data is corrupted

	--*/
	{
	return GetInfo (
	Source,
	SrcSize,
	DstSize,
	ScratchSize
	);
	}

	EFI_STATUS
	EFIAPI
	TianoDecompress (
	IN VOID *Source,
	IN UINT32 SrcSize,
	IN OUT VOID *Destination,
	IN UINT32 DstSize,
	IN OUT VOID *Scratch,
	IN UINT32 ScratchSize
	)
	/*++

	Routine Description:

	The implementation is same as that of EFI_TIANO_DECOMPRESS_PROTOCOL.Decompress().

	Arguments:

	This - The protocol instance pointer
	Source - The source buffer containing the compressed data.
	SrcSize - The size of source buffer
	Destination - The destination buffer to store the decompressed data
	DstSize - The size of destination buffer.
	Scratch - The buffer used internally by the decompress routine. This buffer is needed to store intermediate data.
	ScratchSize - The size of scratch buffer.

	Returns:

	EFI_SUCCESS - Decompression is successfull
	EFI_INVALID_PARAMETER - The source data is corrupted

	--*/
	{
	//
	// For Tiano de/compression algorithm, the version is 2.
	//
	return Decompress (
	Source,
	SrcSize,
	Destination,
	DstSize,
	Scratch,
	ScratchSize,
	2
	);
	}