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Aligned buffers in CTR mode

pull/489/head
Jeffrey Walton 2017-09-04 20:36:08 -04:00
parent e2933070b6
commit b18f74130b
No known key found for this signature in database
GPG Key ID: B36AB348921B1838
1 changed files with 82 additions and 52 deletions
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134
modes.cpp
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@ -34,7 +34,8 @@ void CFB_ModePolicy::Iterate(byte *output, const byte *input, CipherDir dir, siz
{
CRYPTOPP_ASSERT(input);
CRYPTOPP_ASSERT(output);
CRYPTOPP_ASSERT(m_cipher->IsForwardTransformation()); // CFB mode needs the "encrypt" direction of the underlying block cipher, even to decrypt
// CFB mode needs the "encrypt" direction of the underlying block cipher, even to decrypt
CRYPTOPP_ASSERT(m_cipher->IsForwardTransformation());
CRYPTOPP_ASSERT(m_feedbackSize == BlockSize());
const unsigned int s = BlockSize();
@ -57,7 +58,9 @@ void CFB_ModePolicy::Iterate(byte *output, const byte *input, CipherDir dir, siz
void CFB_ModePolicy::TransformRegister()
{
CRYPTOPP_ASSERT(m_cipher->IsForwardTransformation()); // CFB mode needs the "encrypt" direction of the underlying block cipher, even to decrypt
// CFB mode needs the "encrypt" direction of the underlying block cipher, even to decrypt
CRYPTOPP_ASSERT(m_cipher->IsForwardTransformation());
m_cipher->ProcessBlock(m_register, m_temp);
unsigned int updateSize = BlockSize()-m_feedbackSize;
memmove_s(m_register, m_register.size(), m_register+m_feedbackSize, updateSize);
@ -86,7 +89,11 @@ void CFB_ModePolicy::ResizeBuffers()
void OFB_ModePolicy::WriteKeystream(byte *keystreamBuffer, size_t iterationCount)
{
CRYPTOPP_ASSERT(m_cipher->IsForwardTransformation()); // OFB mode needs the "encrypt" direction of the underlying block cipher, even to decrypt
CRYPTOPP_ASSERT(keystreamBuffer);
CRYPTOPP_ASSERT(iterationCount);
// OFB mode needs the "encrypt" direction of the underlying block cipher, even to decrypt
CRYPTOPP_ASSERT(m_cipher->IsForwardTransformation());
const unsigned int s = BlockSize();
m_cipher->ProcessBlock(m_register, keystreamBuffer);
if (iterationCount > 1)
@ -121,31 +128,44 @@ void CTR_ModePolicy::IncrementCounterBy256()
void CTR_ModePolicy::OperateKeystream(KeystreamOperation /*operation*/, byte *output, const byte *input, size_t iterationCount)
{
CRYPTOPP_ASSERT(output);
CRYPTOPP_ASSERT(iterationCount);
// CTR mode needs the "encrypt" direction of the underlying block cipher, even to decrypt
CRYPTOPP_ASSERT(m_cipher->IsForwardTransformation());
const unsigned int s = BlockSize();
const unsigned int inputIncrement = input ? s : 0;
const unsigned int alignment = m_cipher->OptimalDataAlignment();
const byte* is = input; byte* os = output;
AlignedSecByteBlock i, o;
while (iterationCount)
{
byte lsb = m_counterArray[s-1];
const size_t blocks = UnsignedMin(iterationCount, 256U-lsb);
const bool align = !IsAlignedOn(input, alignment) || !IsAlignedOn(output, alignment);
if (align)
is = input; os = output;
if(!IsAlignedOn(input, alignment))
{
AlignedSecByteBlock i(input, blocks*s), o(blocks*s);
m_cipher->AdvancedProcessBlocks(m_counterArray, i, o, blocks*s, BlockTransformation::BT_InBlockIsCounter|BlockTransformation::BT_AllowParallel);
std::memcpy(output, o, blocks*s);
i.Assign(input, blocks*inputIncrement);
is = i.begin();
}
else
if(!IsAlignedOn(output, alignment))
{
m_cipher->AdvancedProcessBlocks(m_counterArray, input, output, blocks*s, BlockTransformation::BT_InBlockIsCounter|BlockTransformation::BT_AllowParallel);
o.Assign(output, blocks*s);
os = o.begin();
}
m_cipher->AdvancedProcessBlocks(m_counterArray, is, os, blocks*s, BlockTransformation::BT_InBlockIsCounter|BlockTransformation::BT_AllowParallel);
if ((m_counterArray[s-1] = lsb + (byte)blocks) == 0)
IncrementCounterBy256();
if(!IsAlignedOn(output, alignment))
{
std::memcpy(output, os, blocks*s);
}
output += blocks*s;
input += blocks*inputIncrement;
iterationCount -= blocks;
@ -163,6 +183,9 @@ void CTR_ModePolicy::CipherResynchronize(byte *keystreamBuffer, const byte *iv,
void BlockOrientedCipherModeBase::UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params)
{
CRYPTOPP_ASSERT(key);
CRYPTOPP_ASSERT(length);
m_cipher->SetKey(key, length, params);
ResizeBuffers();
if (IsResynchronizable())
@ -181,34 +204,40 @@ void BlockOrientedCipherModeBase::ResizeBuffers()
void ECB_OneWay::ProcessData(byte *outString, const byte *inString, size_t length)
{
// If this fires you should align your buffers. There's a non-trival penalty for some processors
CRYPTOPP_ASSERT(IsAlignedOn(inString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(IsAlignedOn(outString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(outString);
CRYPTOPP_ASSERT(inString);
CRYPTOPP_ASSERT(length);
CRYPTOPP_ASSERT(length%BlockSize()==0);
const unsigned int blockSize = BlockSize();
const unsigned int alignment = m_cipher->OptimalDataAlignment();
bool align = !IsAlignedOn(inString, alignment) || !IsAlignedOn(outString, alignment);
const byte* is = inString; byte* os = outString;
if (align)
AlignedSecByteBlock i, o;
if(!IsAlignedOn(inString, alignment))
{
AlignedSecByteBlock i(length), o(length);
std::memcpy(i, inString, length);
std::memcpy(o, outString+length-blockSize, blockSize); // copy tail
m_cipher->AdvancedProcessBlocks(i, NULLPTR, o, length, BlockTransformation::BT_AllowParallel);
std::memcpy(outString, o, length);
i.Assign(inString, length);
is = i.begin();
}
else
if(!IsAlignedOn(outString, alignment))
{
m_cipher->AdvancedProcessBlocks(inString, NULLPTR, outString, length, BlockTransformation::BT_AllowParallel);
o.New(length);
os = o.begin();
}
m_cipher->AdvancedProcessBlocks(is, NULLPTR, os, length, BlockTransformation::BT_AllowParallel);
if(!IsAlignedOn(outString, alignment))
{
std::memcpy(outString, os, length);
}
}
void CBC_Encryption::ProcessData(byte *outString, const byte *inString, size_t length)
{
// If this fires you should align your buffers. There's a non-trival penalty for some processors
// CRYPTOPP_ASSERT(IsAlignedOn(inString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(IsAlignedOn(outString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(outString);
CRYPTOPP_ASSERT(inString);
CRYPTOPP_ASSERT(length);
CRYPTOPP_ASSERT(length%BlockSize()==0);
if (!length)
@ -216,34 +245,36 @@ void CBC_Encryption::ProcessData(byte *outString, const byte *inString, size_t l
const unsigned int blockSize = BlockSize();
const unsigned int alignment = m_cipher->OptimalDataAlignment();
bool align = !IsAlignedOn(inString, alignment) || !IsAlignedOn(outString, alignment);
const byte* is = inString; byte* os = outString;
if (align)
AlignedSecByteBlock i, o;
if(!IsAlignedOn(inString, alignment))
{
AlignedSecByteBlock i(length), o(length);
std::memcpy(i, inString, length);
std::memcpy(o, outString+length-blockSize, blockSize); // copy tail
m_cipher->AdvancedProcessBlocks(i, m_register, o, blockSize, BlockTransformation::BT_XorInput);
if (length > blockSize)
m_cipher->AdvancedProcessBlocks(i+blockSize, o, o+blockSize, length-blockSize, BlockTransformation::BT_XorInput);
std::memcpy(m_register, o + length - blockSize, blockSize);
std::memcpy(outString, o, length);
i.Assign(inString, length);
is = i.begin();
}
else
if(!IsAlignedOn(outString, alignment))
{
m_cipher->AdvancedProcessBlocks(inString, m_register, outString, blockSize, BlockTransformation::BT_XorInput);
if (length > blockSize)
m_cipher->AdvancedProcessBlocks(inString+blockSize, outString, outString+blockSize, length-blockSize, BlockTransformation::BT_XorInput);
std::memcpy(m_register, outString + length - blockSize, blockSize);
o.New(length);
os = o.begin();
}
m_cipher->AdvancedProcessBlocks(inString, m_register, outString, blockSize, BlockTransformation::BT_XorInput);
if (length > blockSize)
m_cipher->AdvancedProcessBlocks(inString+blockSize, outString, outString+blockSize, length-blockSize, BlockTransformation::BT_XorInput);
std::memcpy(m_register, outString + length - blockSize, blockSize);
if(!IsAlignedOn(outString, alignment))
{
std::memcpy(outString, os, length);
}
}
void CBC_CTS_Encryption::ProcessLastBlock(byte *outString, const byte *inString, size_t length)
{
// If this fires you should align your buffers. There's a non-trival penalty for some processors
CRYPTOPP_ASSERT(IsAlignedOn(inString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(IsAlignedOn(outString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(outString);
CRYPTOPP_ASSERT(inString);
CRYPTOPP_ASSERT(length);
if (length <= BlockSize())
{
@ -278,10 +309,9 @@ void CBC_Decryption::ResizeBuffers()
void CBC_Decryption::ProcessData(byte *outString, const byte *inString, size_t length)
{
// If this fires you should align your buffers. There's a non-trival penalty for some processors
CRYPTOPP_ASSERT(IsAlignedOn(inString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(IsAlignedOn(outString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(length%BlockSize()==0);
CRYPTOPP_ASSERT(outString);
CRYPTOPP_ASSERT(inString);
CRYPTOPP_ASSERT(length && length%BlockSize()==0);
if (!length)
return;
@ -290,7 +320,7 @@ void CBC_Decryption::ProcessData(byte *outString, const byte *inString, size_t l
const unsigned int alignment = m_cipher->OptimalDataAlignment();
bool align = !IsAlignedOn(inString, alignment) || !IsAlignedOn(outString, alignment);
if (align)
if (align && false)
{
AlignedSecByteBlock i(length), o(length);
std::memcpy(i, inString, length);
@ -315,9 +345,9 @@ void CBC_Decryption::ProcessData(byte *outString, const byte *inString, size_t l
void CBC_CTS_Decryption::ProcessLastBlock(byte *outString, const byte *inString, size_t length)
{
// If this fires you should align your buffers. There's a non-trival penalty for some processors
CRYPTOPP_ASSERT(IsAlignedOn(inString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(IsAlignedOn(outString, m_cipher->OptimalDataAlignment()));
CRYPTOPP_ASSERT(outString);
CRYPTOPP_ASSERT(inString);
CRYPTOPP_ASSERT(length);
const byte *pn, *pn1;
bool stealIV = length <= BlockSize();