/** @file
UEFI Decompress Library implementation refer to UEFI specification.
Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
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.
**/
#include <Base.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/UefiDecompressLib.h>
#include "BaseUefiDecompressLibInternals.h"
/**
Read NumOfBit of bits from source into mBitBuf.
Shift mBitBuf NumOfBits left. Read in NumOfBits of bits from source.
@param Sd The global scratch data.
@param NumOfBits The number of bits to shift and read.
**/
VOID
FillBuf (
IN SCRATCH_DATA *Sd,
IN UINT16 NumOfBits
)
{
//
// Left shift NumOfBits of bits in advance
//
Sd->mBitBuf = (UINT32) (Sd->mBitBuf << NumOfBits);
//
// Copy data needed in bytes into mSbuBitBuf
//
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 = Sd->mSrcBase[Sd->mInBuf++];
Sd->mBitCount = 8;
} else {
//
// No more bits from the source, just pad zero bit.
//
Sd->mSubBitBuf = 0;
Sd->mBitCount = 8;
}
}
//
// Calculate additional bit count read to update mBitCount
//
Sd->mBitCount = (UINT16) (Sd->mBitCount - NumOfBits);
//
// Copy NumOfBits of bits from mSubBitBuf into mBitBuf
//
Sd->mBitBuf |= Sd->mSubBitBuf >> Sd->mBitCount;
}
/**
Get NumOfBits of bits out from mBitBuf.
Get NumOfBits of bits out from mBitBuf. Fill mBitBuf with subsequent
NumOfBits of bits from source. Returns NumOfBits of bits that are
popped out.
@param Sd The global scratch data.
@param NumOfBits The number of bits to pop and read.
@return The bits that are popped out.
**/
UINT32
GetBits (
IN SCRATCH_DATA *Sd,
IN UINT16 NumOfBits
)
{
UINT32 OutBits;
//
// Pop NumOfBits of Bits from Left
//
OutBits = (UINT32) (Sd->mBitBuf >> (BITBUFSIZ - NumOfBits));
//
// Fill up mBitBuf from source
//
FillBuf (Sd, NumOfBits);
return OutBits;
}
/**
Creates Huffman Code mapping table according to code length array.
Creates Huffman Code mapping table for Extra Set, Char&Len Set
and Position Set according to code length array.
If TableBits > 16, then ASSERT ().
@param Sd The global scratch data.
@param NumOfChar The number of symbols in the symbol set.
@param BitLen Code length array.
@param TableBits The width of the mapping table.
@param Table The table to be created.
@retval 0 OK.
@retval BAD_TABLE The table is corrupted.
**/
UINT16
MakeTable (
IN SCRATCH_DATA *Sd,
IN UINT16 NumOfChar,
IN UINT8 *BitLen,
IN UINT16 TableBits,
OUT UINT16 *Table
)
{
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;
UINT16 WordOfStart;
UINT16 WordOfCount;
//
// The maximum mapping table width supported by this internal
// working function is 16.
//
ASSERT (TableBits <= 16);
for (Index = 0; Index <= 16; Index++) {
Count[Index] = 0;
}
for (Index = 0; Index < NumOfChar; Index++) {
Count[BitLen[Index]]++;
}
Start[0] = 0;
Start[1] = 0;
for (Index = 1; Index <= 16; Index++) {
WordOfStart = Start[Index];
WordOfCount = Count[Index];
Start[Index + 1] = (UINT16) (WordOfStart + (WordOfCount << (16 - Index)));
}
if (Start[17] != 0) {
/*(1U << 16)*/
return (UINT16) BAD_TABLE;
}
JuBits = (UINT16) (16 - TableBits);
Weight[0] = 0;
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);
if (Index < Index3) {
SetMem16 (Table + Index, (Index3 - Index) * sizeof (*Table), 0);
}
}
Avail = NumOfChar;
Mask = (UINT16) (1U << (15 - TableBits));
for (Char = 0; Char < NumOfChar; Char++) {
Len = BitLen[Char];
if (Len == 0 || Len >= 17) {
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 && Avail < (2 * NC - 1)) {
Sd->mRight[Avail] = Sd->mLeft[Avail] = 0;
*Pointer = Avail++;
}
if (*Pointer < (2 * NC - 1)) {
if ((Index3 & Mask) != 0) {
Pointer = &Sd->mRight[*Pointer];
} else {
Pointer = &Sd->mLeft[*Pointer];
}
}
Index3 <<= 1;
Index--;
}
*Pointer = Char;
}
Start[Len] = NextCode;
}
//
// Succeeds
//
return 0;
}
/**
Decodes a position value.
Get a position value according to Position Huffman Table.
@param Sd The global scratch data.
@return The position value decoded.
**/
UINT32
DecodeP (
IN SCRATCH_DATA *Sd
)
{
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) != 0) {
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;
}
/**
Reads code lengths for the Extra Set or the Position Set.
Read in the Extra Set or Position Set Length Array, then
generate the Huffman code mapping for them.
@param Sd The global scratch data.
@param nn The number of symbols.
@param nbit The number of bits needed to represent nn.
@param Special The special symbol that needs to be taken care of.
@retval 0 OK.
@retval BAD_TABLE Table is corrupted.
**/
UINT16
ReadPTLen (
IN SCRATCH_DATA *Sd,
IN UINT16 nn,
IN UINT16 nbit,
IN UINT16 Special
)
{
UINT16 Number;
UINT16 CharC;
UINT16 Index;
UINT32 Mask;
ASSERT (nn <= NPT);
//
// Read Extra Set Code Length Array size
//
Number = (UINT16) GetBits (Sd, nbit);
if (Number == 0) {
//
// This represents only Huffman code used
//
CharC = (UINT16) GetBits (Sd, nbit);
SetMem16 (&Sd->mPTTable[0] , sizeof (Sd->mPTTable), CharC);
SetMem (Sd->mPTLen, nn, 0);
return 0;
}
Index = 0;
while (Index < Number && Index < NPT) {
CharC = (UINT16) (Sd->mBitBuf >> (BITBUFSIZ - 3));
//
// If a code length is less than 7, then it is encoded as a 3-bit
// value. Or it is encoded as a series of "1"s followed by a
// terminating "0". The number of "1"s = Code length - 4.
//
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;
//
// For Code&Len Set,
// After the third length of the code length concatenation,
// a 2-bit value is used to indicated the number of consecutive
// zero lengths after the third length.
//
if (Index == Special) {
CharC = (UINT16) GetBits (Sd, 2);
while ((INT16) (--CharC) >= 0 && Index < NPT) {
Sd->mPTLen[Index++] = 0;
}
}
}
while (Index < nn && Index < NPT) {
Sd->mPTLen[Index++] = 0;
}
return MakeTable (Sd, nn, Sd->mPTLen, 8, Sd->mPTTable);
}
/**
Reads code lengths for Char&Len Set.
Read in and decode the Char&Len Set Code Length Array, then
generate the Huffman Code mapping table for the Char&Len Set.
@param Sd The global scratch data.
**/
VOID
ReadCLen (
SCRATCH_DATA *Sd
)
{
UINT16 Number;
UINT16 CharC;
UINT16 Index;
UINT32 Mask;
Number = (UINT16) GetBits (Sd, CBIT);
if (Number == 0) {
//
// This represents only Huffman code used
//
CharC = (UINT16) GetBits (Sd, CBIT);
SetMem (Sd->mCLen, NC, 0);
SetMem16 (&Sd->mCTable[0], sizeof (Sd->mCTable), CharC);
return ;
}
Index = 0;
while (Index < Number && Index < NC) {
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 && Index < NC) {
Sd->mCLen[Index++] = 0;
}
} else {
Sd->mCLen[Index++] = (UINT8) (CharC - 2);
}
}
SetMem (Sd->mCLen + Index, NC - Index, 0);
MakeTable (Sd, NC, Sd->mCLen, 12, Sd->mCTable);
return ;
}
/**
Decode a character/length value.
Read one value from mBitBuf, Get one code from mBitBuf. If it is at block boundary, generates
Huffman code mapping table for Extra Set, Code&Len Set and
Position Set.
@param Sd The global scratch data.
@return The value decoded.
**/
UINT16
DecodeC (
SCRATCH_DATA *Sd
)
{
UINT16 Index2;
UINT32 Mask;
if (Sd->mBlockSize == 0) {
//
// Starting a new block
// Read BlockSize from block header
//
Sd->mBlockSize = (UINT16) GetBits (Sd, 16);
//
// Read in the Extra Set Code Length Array,
// Generate the Huffman code mapping table for Extra Set.
//
Sd->mBadTableFlag = ReadPTLen (Sd, NT, TBIT, 3);
if (Sd->mBadTableFlag != 0) {
return 0;
}
//
// Read in and decode the Char&Len Set Code Length Array,
// Generate the Huffman code mapping table for Char&Len Set.
//
ReadCLen (Sd);
//
// Read in the Position Set Code Length Array,
// Generate the Huffman code mapping table for the Position Set.
//
Sd->mBadTableFlag = ReadPTLen (Sd, MAXNP, Sd->mPBit, (UINT16) (-1));
if (Sd->mBadTableFlag != 0) {
return 0;
}
}
//
// Get one code according to Code&Set Huffman Table
//
Sd->mBlockSize--;
Index2 = Sd->mCTable[Sd->mBitBuf >> (BITBUFSIZ - 12)];
if (Index2 >= NC) {
Mask = 1U << (BITBUFSIZ - 1 - 12);
do {
if ((Sd->mBitBuf & Mask) != 0) {
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;
}
/**
Decode the source data and put the resulting data into the destination buffer.
@param Sd The global scratch data.
**/
VOID
Decode (
SCRATCH_DATA *Sd
)
{
UINT16 BytesRemain;
UINT32 DataIdx;
UINT16 CharC;
BytesRemain = (UINT16) (-1);
DataIdx = 0;
for (;;) {
//
// Get one code from mBitBuf
//
CharC = DecodeC (Sd);
if (Sd->mBadTableFlag != 0) {
goto Done;
}
if (CharC < 256) {
//
// Process an Original character
//
if (Sd->mOutBuf >= Sd->mOrigSize) {
goto Done;
} else {
//
// Write orignal character into mDstBase
//
Sd->mDstBase[Sd->mOutBuf++] = (UINT8) CharC;
}
} else {
//
// Process a Pointer
//
CharC = (UINT16) (CharC - (BIT8 - THRESHOLD));
//
// Get string length
//
BytesRemain = CharC;
//
// Locate string position
//
DataIdx = Sd->mOutBuf - DecodeP (Sd) - 1;
//
// Write BytesRemain of bytes into mDstBase
//
BytesRemain--;
while ((INT16) (BytesRemain) >= 0) {
Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];
if (Sd->mOutBuf >= Sd->mOrigSize) {
goto Done;
}
BytesRemain--;
}
}
}
Done:
return ;
}
/**
Given a compressed source buffer, this function retrieves the size of
the uncompressed buffer and the size of the scratch buffer required
to decompress the compressed source buffer.
Retrieves the size of the uncompressed buffer and the temporary scratch buffer
required to decompress the buffer specified by Source and SourceSize.
If the size of the uncompressed buffer or the size of the scratch buffer cannot
be determined from the compressed data specified by Source and SourceData,
then RETURN_INVALID_PARAMETER is returned. Otherwise, the size of the uncompressed
buffer is returned in DestinationSize, the size of the scratch buffer is returned
in ScratchSize, and RETURN_SUCCESS is returned.
This function does not have scratch buffer available to perform a thorough
checking of the validity of the source data. It just retrieves the "Original Size"
field from the beginning bytes of the source data and output it as DestinationSize.
And ScratchSize is specific to the decompression implementation.
If Source is NULL, then ASSERT().
If DestinationSize is NULL, then ASSERT().
If ScratchSize is NULL, then ASSERT().
@param Source The source buffer containing the compressed data.
@param SourceSize The size, in bytes, of the source buffer.
@param DestinationSize A pointer to the size, in bytes, of the uncompressed buffer
that will be generated when the compressed buffer specified
by Source and SourceSize is decompressed.
@param ScratchSize A pointer to the size, in bytes, of the scratch buffer that
is required to decompress the compressed buffer specified
by Source and SourceSize.
@retval RETURN_SUCCESS The size of the uncompressed data was returned
in DestinationSize, and the size of the scratch
buffer was returned in ScratchSize.
@retval RETURN_INVALID_PARAMETER
The size of the uncompressed data or the size of
the scratch buffer cannot be determined from
the compressed data specified by Source
and SourceSize.
**/
RETURN_STATUS
EFIAPI
UefiDecompressGetInfo (
IN CONST VOID *Source,
IN UINT32 SourceSize,
OUT UINT32 *DestinationSize,
OUT UINT32 *ScratchSize
)
{
UINT32 CompressedSize;
ASSERT (Source != NULL);
ASSERT (DestinationSize != NULL);
ASSERT (ScratchSize != NULL);
if (SourceSize < 8) {
return RETURN_INVALID_PARAMETER;
}
CompressedSize = ReadUnaligned32 ((UINT32 *)Source);
if (SourceSize < (CompressedSize + 8)) {
return RETURN_INVALID_PARAMETER;
}
*ScratchSize = sizeof (SCRATCH_DATA);
*DestinationSize = ReadUnaligned32 ((UINT32 *)Source + 1);
return RETURN_SUCCESS;
}
/**
Decompresses a compressed source buffer.
Extracts decompressed data to its original form.
This function is designed so that the decompression algorithm can be implemented
without using any memory services. As a result, this function is not allowed to
call any memory allocation services in its implementation. It is the caller's
responsibility to allocate and free the Destination and Scratch buffers.
If the compressed source data specified by Source is successfully decompressed
into Destination, then RETURN_SUCCESS is returned. If the compressed source data
specified by Source is not in a valid compressed data format,
then RETURN_INVALID_PARAMETER is returned.
If Source is NULL, then ASSERT().
If Destination is NULL, then ASSERT().
If the required scratch buffer size > 0 and Scratch is NULL, then ASSERT().
@param Source The source buffer containing the compressed data.
@param Destination The destination buffer to store the decompressed data.
@param Scratch A temporary scratch buffer that is used to perform the decompression.
This is an optional parameter that may be NULL if the
required scratch buffer size is 0.
@retval RETURN_SUCCESS Decompression completed successfully, and
the uncompressed buffer is returned in Destination.
@retval RETURN_INVALID_PARAMETER
The source buffer specified by Source is corrupted
(not in a valid compressed format).
**/
RETURN_STATUS
EFIAPI
UefiDecompress (
IN CONST VOID *Source,
IN OUT VOID *Destination,
IN OUT VOID *Scratch OPTIONAL
)
{
UINT32 CompSize;
UINT32 OrigSize;
SCRATCH_DATA *Sd;
CONST UINT8 *Src;
UINT8 *Dst;
ASSERT (Source != NULL);
ASSERT (Destination != NULL);
ASSERT (Scratch != NULL);
Src = Source;
Dst = Destination;
Sd = (SCRATCH_DATA *) Scratch;
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 RETURN_SUCCESS;
}
Src = Src + 8;
SetMem (Sd, sizeof (SCRATCH_DATA), 0);
//
// The length of the field 'Position Set Code Length Array Size' in Block Header.
// For UEFI 2.0 de/compression algorithm(Version 1), mPBit = 4
//
Sd->mPBit = 4;
Sd->mSrcBase = (UINT8 *)Src;
Sd->mDstBase = Dst;
//
// CompSize and OrigSize are calculated in bytes
//
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
//
return RETURN_INVALID_PARAMETER;
}
return RETURN_SUCCESS;
}