diff options
Diffstat (limited to 'plugins/CryptoPP/crypto/zinflate.cpp')
| -rw-r--r-- | plugins/CryptoPP/crypto/zinflate.cpp | 621 |
1 files changed, 621 insertions, 0 deletions
diff --git a/plugins/CryptoPP/crypto/zinflate.cpp b/plugins/CryptoPP/crypto/zinflate.cpp new file mode 100644 index 0000000000..7a0c8aa110 --- /dev/null +++ b/plugins/CryptoPP/crypto/zinflate.cpp @@ -0,0 +1,621 @@ +// zinflate.cpp - written and placed in the public domain by Wei Dai
+
+// This is a complete reimplementation of the DEFLATE decompression algorithm.
+// It should not be affected by any security vulnerabilities in the zlib
+// compression library. In particular it is not affected by the double free bug
+// (http://www.kb.cert.org/vuls/id/368819).
+
+#include "pch.h"
+#include "zinflate.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+struct CodeLessThan
+{
+ inline bool operator()(CryptoPP::HuffmanDecoder::code_t lhs, const CryptoPP::HuffmanDecoder::CodeInfo &rhs)
+ {return lhs < rhs.code;}
+ // needed for MSVC .NET 2005
+ inline bool operator()(const CryptoPP::HuffmanDecoder::CodeInfo &lhs, const CryptoPP::HuffmanDecoder::CodeInfo &rhs)
+ {return lhs.code < rhs.code;}
+};
+
+inline bool LowFirstBitReader::FillBuffer(unsigned int length)
+{
+ while (m_bitsBuffered < length)
+ {
+ byte b;
+ if (!m_store.Get(b))
+ return false;
+ m_buffer |= (unsigned long)b << m_bitsBuffered;
+ m_bitsBuffered += 8;
+ }
+ assert(m_bitsBuffered <= sizeof(unsigned long)*8);
+ return true;
+}
+
+inline unsigned long LowFirstBitReader::PeekBits(unsigned int length)
+{
+ bool result = FillBuffer(length);
+ assert(result);
+ return m_buffer & (((unsigned long)1 << length) - 1);
+}
+
+inline void LowFirstBitReader::SkipBits(unsigned int length)
+{
+ assert(m_bitsBuffered >= length);
+ m_buffer >>= length;
+ m_bitsBuffered -= length;
+}
+
+inline unsigned long LowFirstBitReader::GetBits(unsigned int length)
+{
+ unsigned long result = PeekBits(length);
+ SkipBits(length);
+ return result;
+}
+
+inline HuffmanDecoder::code_t HuffmanDecoder::NormalizeCode(HuffmanDecoder::code_t code, unsigned int codeBits)
+{
+ return code << (MAX_CODE_BITS - codeBits);
+}
+
+void HuffmanDecoder::Initialize(const unsigned int *codeBits, unsigned int nCodes)
+{
+ // the Huffman codes are represented in 3 ways in this code:
+ //
+ // 1. most significant code bit (i.e. top of code tree) in the least significant bit position
+ // 2. most significant code bit (i.e. top of code tree) in the most significant bit position
+ // 3. most significant code bit (i.e. top of code tree) in n-th least significant bit position,
+ // where n is the maximum code length for this code tree
+ //
+ // (1) is the way the codes come in from the deflate stream
+ // (2) is used to sort codes so they can be binary searched
+ // (3) is used in this function to compute codes from code lengths
+ //
+ // a code in representation (2) is called "normalized" here
+ // The BitReverse() function is used to convert between (1) and (2)
+ // The NormalizeCode() function is used to convert from (3) to (2)
+
+ if (nCodes == 0)
+ throw Err("null code");
+
+ m_maxCodeBits = *std::max_element(codeBits, codeBits+nCodes);
+
+ if (m_maxCodeBits > MAX_CODE_BITS)
+ throw Err("code length exceeds maximum");
+
+ if (m_maxCodeBits == 0)
+ throw Err("null code");
+
+ // count number of codes of each length
+ SecBlockWithHint<unsigned int, 15+1> blCount(m_maxCodeBits+1);
+ std::fill(blCount.begin(), blCount.end(), 0);
+ unsigned int i;
+ for (i=0; i<nCodes; i++)
+ blCount[codeBits[i]]++;
+
+ // compute the starting code of each length
+ code_t code = 0;
+ SecBlockWithHint<code_t, 15+1> nextCode(m_maxCodeBits+1);
+ nextCode[1] = 0;
+ for (i=2; i<=m_maxCodeBits; i++)
+ {
+ // compute this while checking for overflow: code = (code + blCount[i-1]) << 1
+ if (code > code + blCount[i-1])
+ throw Err("codes oversubscribed");
+ code += blCount[i-1];
+ if (code > (code << 1))
+ throw Err("codes oversubscribed");
+ code <<= 1;
+ nextCode[i] = code;
+ }
+
+ if (code > (1 << m_maxCodeBits) - blCount[m_maxCodeBits])
+ throw Err("codes oversubscribed");
+ else if (m_maxCodeBits != 1 && code < (1 << m_maxCodeBits) - blCount[m_maxCodeBits])
+ throw Err("codes incomplete");
+
+ // compute a vector of <code, length, value> triples sorted by code
+ m_codeToValue.resize(nCodes - blCount[0]);
+ unsigned int j=0;
+ for (i=0; i<nCodes; i++)
+ {
+ unsigned int len = codeBits[i];
+ if (len != 0)
+ {
+ code = NormalizeCode(nextCode[len]++, len);
+ m_codeToValue[j].code = code;
+ m_codeToValue[j].len = len;
+ m_codeToValue[j].value = i;
+ j++;
+ }
+ }
+ std::sort(m_codeToValue.begin(), m_codeToValue.end());
+
+ // initialize the decoding cache
+ m_cacheBits = STDMIN(9U, m_maxCodeBits);
+ m_cacheMask = (1 << m_cacheBits) - 1;
+ m_normalizedCacheMask = NormalizeCode(m_cacheMask, m_cacheBits);
+ assert(m_normalizedCacheMask == BitReverse(m_cacheMask));
+
+ if (m_cache.size() != size_t(1) << m_cacheBits)
+ m_cache.resize(1 << m_cacheBits);
+
+ for (i=0; i<m_cache.size(); i++)
+ m_cache[i].type = 0;
+}
+
+void HuffmanDecoder::FillCacheEntry(LookupEntry &entry, code_t normalizedCode) const
+{
+ normalizedCode &= m_normalizedCacheMask;
+ const CodeInfo &codeInfo = *(std::upper_bound(m_codeToValue.begin(), m_codeToValue.end(), normalizedCode, CodeLessThan())-1);
+ if (codeInfo.len <= m_cacheBits)
+ {
+ entry.type = 1;
+ entry.value = codeInfo.value;
+ entry.len = codeInfo.len;
+ }
+ else
+ {
+ entry.begin = &codeInfo;
+ const CodeInfo *last = & *(std::upper_bound(m_codeToValue.begin(), m_codeToValue.end(), normalizedCode + ~m_normalizedCacheMask, CodeLessThan())-1);
+ if (codeInfo.len == last->len)
+ {
+ entry.type = 2;
+ entry.len = codeInfo.len;
+ }
+ else
+ {
+ entry.type = 3;
+ entry.end = last+1;
+ }
+ }
+}
+
+inline unsigned int HuffmanDecoder::Decode(code_t code, /* out */ value_t &value) const
+{
+ assert(m_codeToValue.size() > 0);
+ LookupEntry &entry = m_cache[code & m_cacheMask];
+
+ code_t normalizedCode;
+ if (entry.type != 1)
+ normalizedCode = BitReverse(code);
+
+ if (entry.type == 0)
+ FillCacheEntry(entry, normalizedCode);
+
+ if (entry.type == 1)
+ {
+ value = entry.value;
+ return entry.len;
+ }
+ else
+ {
+ const CodeInfo &codeInfo = (entry.type == 2)
+ ? entry.begin[(normalizedCode << m_cacheBits) >> (MAX_CODE_BITS - (entry.len - m_cacheBits))]
+ : *(std::upper_bound(entry.begin, entry.end, normalizedCode, CodeLessThan())-1);
+ value = codeInfo.value;
+ return codeInfo.len;
+ }
+}
+
+bool HuffmanDecoder::Decode(LowFirstBitReader &reader, value_t &value) const
+{
+ reader.FillBuffer(m_maxCodeBits);
+ unsigned int codeBits = Decode(reader.PeekBuffer(), value);
+ if (codeBits > reader.BitsBuffered())
+ return false;
+ reader.SkipBits(codeBits);
+ return true;
+}
+
+// *************************************************************
+
+Inflator::Inflator(BufferedTransformation *attachment, bool repeat, int propagation)
+ : AutoSignaling<Filter>(propagation)
+ , m_state(PRE_STREAM), m_repeat(repeat), m_reader(m_inQueue)
+{
+ Detach(attachment);
+}
+
+void Inflator::IsolatedInitialize(const NameValuePairs ¶meters)
+{
+ m_state = PRE_STREAM;
+ parameters.GetValue("Repeat", m_repeat);
+ m_inQueue.Clear();
+ m_reader.SkipBits(m_reader.BitsBuffered());
+}
+
+void Inflator::OutputByte(byte b)
+{
+ m_window[m_current++] = b;
+ if (m_current == m_window.size())
+ {
+ ProcessDecompressedData(m_window + m_lastFlush, m_window.size() - m_lastFlush);
+ m_lastFlush = 0;
+ m_current = 0;
+ m_wrappedAround = true;
+ }
+}
+
+void Inflator::OutputString(const byte *string, size_t length)
+{
+ while (length)
+ {
+ size_t len = UnsignedMin(length, m_window.size() - m_current);
+ memcpy(m_window + m_current, string, len);
+ m_current += len;
+ if (m_current == m_window.size())
+ {
+ ProcessDecompressedData(m_window + m_lastFlush, m_window.size() - m_lastFlush);
+ m_lastFlush = 0;
+ m_current = 0;
+ m_wrappedAround = true;
+ }
+ string += len;
+ length -= len;
+ }
+}
+
+void Inflator::OutputPast(unsigned int length, unsigned int distance)
+{
+ size_t start;
+ if (distance <= m_current)
+ start = m_current - distance;
+ else if (m_wrappedAround && distance <= m_window.size())
+ start = m_current + m_window.size() - distance;
+ else
+ throw BadBlockErr();
+
+ if (start + length > m_window.size())
+ {
+ for (; start < m_window.size(); start++, length--)
+ OutputByte(m_window[start]);
+ start = 0;
+ }
+
+ if (start + length > m_current || m_current + length >= m_window.size())
+ {
+ while (length--)
+ OutputByte(m_window[start++]);
+ }
+ else
+ {
+ memcpy(m_window + m_current, m_window + start, length);
+ m_current += length;
+ }
+}
+
+size_t Inflator::Put2(const byte *inString, size_t length, int messageEnd, bool blocking)
+{
+ if (!blocking)
+ throw BlockingInputOnly("Inflator");
+
+ LazyPutter lp(m_inQueue, inString, length);
+ ProcessInput(messageEnd != 0);
+
+ if (messageEnd)
+ if (!(m_state == PRE_STREAM || m_state == AFTER_END))
+ throw UnexpectedEndErr();
+
+ Output(0, NULL, 0, messageEnd, blocking);
+ return 0;
+}
+
+bool Inflator::IsolatedFlush(bool hardFlush, bool blocking)
+{
+ if (!blocking)
+ throw BlockingInputOnly("Inflator");
+
+ if (hardFlush)
+ ProcessInput(true);
+ FlushOutput();
+
+ return false;
+}
+
+void Inflator::ProcessInput(bool flush)
+{
+ while (true)
+ {
+ switch (m_state)
+ {
+ case PRE_STREAM:
+ if (!flush && m_inQueue.CurrentSize() < MaxPrestreamHeaderSize())
+ return;
+ ProcessPrestreamHeader();
+ m_state = WAIT_HEADER;
+ m_wrappedAround = false;
+ m_current = 0;
+ m_lastFlush = 0;
+ m_window.New(1 << GetLog2WindowSize());
+ break;
+ case WAIT_HEADER:
+ {
+ // maximum number of bytes before actual compressed data starts
+ const size_t MAX_HEADER_SIZE = BitsToBytes(3+5+5+4+19*7+286*15+19*15);
+ if (m_inQueue.CurrentSize() < (flush ? 1 : MAX_HEADER_SIZE))
+ return;
+ DecodeHeader();
+ break;
+ }
+ case DECODING_BODY:
+ if (!DecodeBody())
+ return;
+ break;
+ case POST_STREAM:
+ if (!flush && m_inQueue.CurrentSize() < MaxPoststreamTailSize())
+ return;
+ ProcessPoststreamTail();
+ m_state = m_repeat ? PRE_STREAM : AFTER_END;
+ Output(0, NULL, 0, GetAutoSignalPropagation(), true); // TODO: non-blocking
+ if (m_inQueue.IsEmpty())
+ return;
+ break;
+ case AFTER_END:
+ m_inQueue.TransferTo(*AttachedTransformation());
+ return;
+ }
+ }
+}
+
+void Inflator::DecodeHeader()
+{
+ if (!m_reader.FillBuffer(3))
+ throw UnexpectedEndErr();
+ m_eof = m_reader.GetBits(1) != 0;
+ m_blockType = (byte)m_reader.GetBits(2);
+ switch (m_blockType)
+ {
+ case 0: // stored
+ {
+ m_reader.SkipBits(m_reader.BitsBuffered() % 8);
+ if (!m_reader.FillBuffer(32))
+ throw UnexpectedEndErr();
+ m_storedLen = (word16)m_reader.GetBits(16);
+ word16 nlen = (word16)m_reader.GetBits(16);
+ if (nlen != (word16)~m_storedLen)
+ throw BadBlockErr();
+ break;
+ }
+ case 1: // fixed codes
+ m_nextDecode = LITERAL;
+ break;
+ case 2: // dynamic codes
+ {
+ if (!m_reader.FillBuffer(5+5+4))
+ throw UnexpectedEndErr();
+ unsigned int hlit = m_reader.GetBits(5);
+ unsigned int hdist = m_reader.GetBits(5);
+ unsigned int hclen = m_reader.GetBits(4);
+
+ FixedSizeSecBlock<unsigned int, 286+32> codeLengths;
+ unsigned int i;
+ static const unsigned int border[] = { // Order of the bit length code lengths
+ 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
+ std::fill(codeLengths.begin(), codeLengths+19, 0);
+ for (i=0; i<hclen+4; i++)
+ codeLengths[border[i]] = m_reader.GetBits(3);
+
+ try
+ {
+ HuffmanDecoder codeLengthDecoder(codeLengths, 19);
+ for (i = 0; i < hlit+257+hdist+1; )
+ {
+ unsigned int k, count, repeater;
+ bool result = codeLengthDecoder.Decode(m_reader, k);
+ if (!result)
+ throw UnexpectedEndErr();
+ if (k <= 15)
+ {
+ count = 1;
+ repeater = k;
+ }
+ else switch (k)
+ {
+ case 16:
+ if (!m_reader.FillBuffer(2))
+ throw UnexpectedEndErr();
+ count = 3 + m_reader.GetBits(2);
+ if (i == 0)
+ throw BadBlockErr();
+ repeater = codeLengths[i-1];
+ break;
+ case 17:
+ if (!m_reader.FillBuffer(3))
+ throw UnexpectedEndErr();
+ count = 3 + m_reader.GetBits(3);
+ repeater = 0;
+ break;
+ case 18:
+ if (!m_reader.FillBuffer(7))
+ throw UnexpectedEndErr();
+ count = 11 + m_reader.GetBits(7);
+ repeater = 0;
+ break;
+ }
+ if (i + count > hlit+257+hdist+1)
+ throw BadBlockErr();
+ std::fill(codeLengths + i, codeLengths + i + count, repeater);
+ i += count;
+ }
+ m_dynamicLiteralDecoder.Initialize(codeLengths, hlit+257);
+ if (hdist == 0 && codeLengths[hlit+257] == 0)
+ {
+ if (hlit != 0) // a single zero distance code length means all literals
+ throw BadBlockErr();
+ }
+ else
+ m_dynamicDistanceDecoder.Initialize(codeLengths+hlit+257, hdist+1);
+ m_nextDecode = LITERAL;
+ }
+ catch (HuffmanDecoder::Err &)
+ {
+ throw BadBlockErr();
+ }
+ break;
+ }
+ default:
+ throw BadBlockErr(); // reserved block type
+ }
+ m_state = DECODING_BODY;
+}
+
+bool Inflator::DecodeBody()
+{
+ bool blockEnd = false;
+ switch (m_blockType)
+ {
+ case 0: // stored
+ assert(m_reader.BitsBuffered() == 0);
+ while (!m_inQueue.IsEmpty() && !blockEnd)
+ {
+ size_t size;
+ const byte *block = m_inQueue.Spy(size);
+ size = UnsignedMin(m_storedLen, size);
+ OutputString(block, size);
+ m_inQueue.Skip(size);
+ m_storedLen -= (word16)size;
+ if (m_storedLen == 0)
+ blockEnd = true;
+ }
+ break;
+ case 1: // fixed codes
+ case 2: // dynamic codes
+ static const unsigned int lengthStarts[] = {
+ 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
+ 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258};
+ static const unsigned int lengthExtraBits[] = {
+ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
+ 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0};
+ static const unsigned int distanceStarts[] = {
+ 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
+ 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
+ 8193, 12289, 16385, 24577};
+ static const unsigned int distanceExtraBits[] = {
+ 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+ 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+ 12, 12, 13, 13};
+
+ const HuffmanDecoder& literalDecoder = GetLiteralDecoder();
+ const HuffmanDecoder& distanceDecoder = GetDistanceDecoder();
+
+ switch (m_nextDecode)
+ {
+ case LITERAL:
+ while (true)
+ {
+ if (!literalDecoder.Decode(m_reader, m_literal))
+ {
+ m_nextDecode = LITERAL;
+ break;
+ }
+ if (m_literal < 256)
+ OutputByte((byte)m_literal);
+ else if (m_literal == 256) // end of block
+ {
+ blockEnd = true;
+ break;
+ }
+ else
+ {
+ if (m_literal > 285)
+ throw BadBlockErr();
+ unsigned int bits;
+ case LENGTH_BITS:
+ bits = lengthExtraBits[m_literal-257];
+ if (!m_reader.FillBuffer(bits))
+ {
+ m_nextDecode = LENGTH_BITS;
+ break;
+ }
+ m_literal = m_reader.GetBits(bits) + lengthStarts[m_literal-257];
+ case DISTANCE:
+ if (!distanceDecoder.Decode(m_reader, m_distance))
+ {
+ m_nextDecode = DISTANCE;
+ break;
+ }
+ case DISTANCE_BITS:
+ bits = distanceExtraBits[m_distance];
+ if (!m_reader.FillBuffer(bits))
+ {
+ m_nextDecode = DISTANCE_BITS;
+ break;
+ }
+ m_distance = m_reader.GetBits(bits) + distanceStarts[m_distance];
+ OutputPast(m_literal, m_distance);
+ }
+ }
+ }
+ }
+ if (blockEnd)
+ {
+ if (m_eof)
+ {
+ FlushOutput();
+ m_reader.SkipBits(m_reader.BitsBuffered()%8);
+ if (m_reader.BitsBuffered())
+ {
+ // undo too much lookahead
+ SecBlockWithHint<byte, 4> buffer(m_reader.BitsBuffered() / 8);
+ for (unsigned int i=0; i<buffer.size(); i++)
+ buffer[i] = (byte)m_reader.GetBits(8);
+ m_inQueue.Unget(buffer, buffer.size());
+ }
+ m_state = POST_STREAM;
+ }
+ else
+ m_state = WAIT_HEADER;
+ }
+ return blockEnd;
+}
+
+void Inflator::FlushOutput()
+{
+ if (m_state != PRE_STREAM)
+ {
+ assert(m_current >= m_lastFlush);
+ ProcessDecompressedData(m_window + m_lastFlush, m_current - m_lastFlush);
+ m_lastFlush = m_current;
+ }
+}
+
+struct NewFixedLiteralDecoder
+{
+ HuffmanDecoder * operator()() const
+ {
+ unsigned int codeLengths[288];
+ std::fill(codeLengths + 0, codeLengths + 144, 8);
+ std::fill(codeLengths + 144, codeLengths + 256, 9);
+ std::fill(codeLengths + 256, codeLengths + 280, 7);
+ std::fill(codeLengths + 280, codeLengths + 288, 8);
+ std::auto_ptr<HuffmanDecoder> pDecoder(new HuffmanDecoder);
+ pDecoder->Initialize(codeLengths, 288);
+ return pDecoder.release();
+ }
+};
+
+struct NewFixedDistanceDecoder
+{
+ HuffmanDecoder * operator()() const
+ {
+ unsigned int codeLengths[32];
+ std::fill(codeLengths + 0, codeLengths + 32, 5);
+ std::auto_ptr<HuffmanDecoder> pDecoder(new HuffmanDecoder);
+ pDecoder->Initialize(codeLengths, 32);
+ return pDecoder.release();
+ }
+};
+
+const HuffmanDecoder& Inflator::GetLiteralDecoder() const
+{
+ return m_blockType == 1 ? Singleton<HuffmanDecoder, NewFixedLiteralDecoder>().Ref() : m_dynamicLiteralDecoder;
+}
+
+const HuffmanDecoder& Inflator::GetDistanceDecoder() const
+{
+ return m_blockType == 1 ? Singleton<HuffmanDecoder, NewFixedDistanceDecoder>().Ref() : m_dynamicDistanceDecoder;
+}
+
+NAMESPACE_END
|