Initial revision

git-svn-id: svn://svn.code.sf.net/p/cryptopp/code/trunk/c5@2 57ff6487-cd31-0410-9ec3-f628ee90f5f0

1 files changed, 151 insertions, 0 deletions

diff --git a/pkcspad.cpp b/pkcspad.cpp
new file mode 100644
index 0000000..e94a1fd
--- /dev/null
+++ b/pkcspad.cpp
@@ -0,0 +1,151 @@
+// pkcspad.cpp - written and placed in the public domain by Wei Dai
+
+#include "pch.h"
+#include "pkcspad.h"
+#include <assert.h>
+
+NAMESPACE_BEGIN(CryptoPP)
+
+template<> const byte PKCS_DigestDecoration<SHA>::decoration[] = {0x30,0x21,0x30,0x09,0x06,0x05,0x2B,0x0E,0x03,0x02,0x1A,0x05,0x00,0x04,0x14};
+template<> const unsigned int PKCS_DigestDecoration<SHA>::length = sizeof(PKCS_DigestDecoration<SHA>::decoration);
+
+template<> const byte PKCS_DigestDecoration<MD2>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x02,0x05,0x00,0x04,0x10};
+template<> const unsigned int PKCS_DigestDecoration<MD2>::length = sizeof(PKCS_DigestDecoration<MD2>::decoration);
+
+template<> const byte PKCS_DigestDecoration<MD5>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x05,0x05,0x00,0x04,0x10};
+template<> const unsigned int PKCS_DigestDecoration<MD5>::length = sizeof(PKCS_DigestDecoration<MD5>::decoration);
+
+template<> const byte PKCS_DigestDecoration<RIPEMD160>::decoration[] = {0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x24,0x03,0x02,0x01,0x05,0x00,0x04,0x14};
+template<> const unsigned int PKCS_DigestDecoration<RIPEMD160>::length = sizeof(PKCS_DigestDecoration<RIPEMD160>::decoration);
+
+template<> const byte PKCS_DigestDecoration<SHA256>::decoration[] = {0x30,0x31,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x01,0x05,0x00,0x04,0x20};
+template<> const unsigned int PKCS_DigestDecoration<SHA256>::length = sizeof(PKCS_DigestDecoration<SHA256>::decoration);
+
+template<> const byte PKCS_DigestDecoration<SHA384>::decoration[] = {0x30,0x41,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x02,0x05,0x00,0x04,0x30};
+template<> const unsigned int PKCS_DigestDecoration<SHA384>::length = sizeof(PKCS_DigestDecoration<SHA384>::decoration);
+
+template<> const byte PKCS_DigestDecoration<SHA512>::decoration[] = {0x30,0x51,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x03,0x05,0x00,0x04,0x40};
+template<> const unsigned int PKCS_DigestDecoration<SHA512>::length = sizeof(PKCS_DigestDecoration<SHA512>::decoration);
+
+
+
+unsigned int PKCS_EncryptionPaddingScheme::MaxUnpaddedLength(unsigned int paddedLength) const
+{
+	return paddedLength/8 > 10 ? paddedLength/8-10 : 0;
+}
+
+void PKCS_EncryptionPaddingScheme::Pad(RandomNumberGenerator &rng, const byte *input, unsigned int inputLen, byte *pkcsBlock, unsigned int pkcsBlockLen) const
+{
+	assert (inputLen <= MaxUnpaddedLength(pkcsBlockLen));	// this should be checked by caller
+
+	// convert from bit length to byte length
+	if (pkcsBlockLen % 8 != 0)
+	{
+		pkcsBlock[0] = 0;
+		pkcsBlock++;
+	}
+	pkcsBlockLen /= 8;
+
+	pkcsBlock[0] = 2;  // block type 2
+
+	// pad with non-zero random bytes
+	for (unsigned i = 1; i < pkcsBlockLen-inputLen-1; i++)
+		pkcsBlock[i] = (byte)rng.GenerateWord32(1, 0xff);
+
+	pkcsBlock[pkcsBlockLen-inputLen-1] = 0;     // separator
+	memcpy(pkcsBlock+pkcsBlockLen-inputLen, input, inputLen);
+}
+
+DecodingResult PKCS_EncryptionPaddingScheme::Unpad(const byte *pkcsBlock, unsigned int pkcsBlockLen, byte *output) const
+{
+	bool invalid = false;
+	unsigned int maxOutputLen = MaxUnpaddedLength(pkcsBlockLen);
+
+	// convert from bit length to byte length
+	if (pkcsBlockLen % 8 != 0)
+	{
+		invalid = (pkcsBlock[0] != 0) || invalid;
+		pkcsBlock++;
+	}
+	pkcsBlockLen /= 8;
+
+	// Require block type 2.
+	invalid = (pkcsBlock[0] != 2) || invalid;
+
+	// skip past the padding until we find the seperator
+	unsigned i=1;
+	while (i<pkcsBlockLen && pkcsBlock[i++]) { // null body
+		}
+	assert(i==pkcsBlockLen || pkcsBlock[i-1]==0);
+
+	unsigned int outputLen = pkcsBlockLen - i;
+	invalid = (outputLen > maxOutputLen) || invalid;
+
+	if (invalid)
+		return DecodingResult();
+
+	memcpy (output, pkcsBlock+i, outputLen);
+	return DecodingResult(outputLen);
+}
+
+// ********************************************************
+
+unsigned int PKCS_SignaturePaddingScheme::MaxUnpaddedLength(unsigned int paddedLength) const
+{
+	return paddedLength/8 > 10 ? paddedLength/8-10 : 0;
+}
+
+void PKCS_SignaturePaddingScheme::Pad(RandomNumberGenerator &, const byte *input, unsigned int inputLen, byte *pkcsBlock, unsigned int pkcsBlockLen) const
+{
+	assert (inputLen <= MaxUnpaddedLength(pkcsBlockLen));	// this should be checked by caller
+
+	// convert from bit length to byte length
+	if (pkcsBlockLen % 8 != 0)
+	{
+		pkcsBlock[0] = 0;
+		pkcsBlock++;
+	}
+	pkcsBlockLen /= 8;
+
+	pkcsBlock[0] = 1;   // block type 1
+
+	// padd with 0xff
+	memset(pkcsBlock+1, 0xff, pkcsBlockLen-inputLen-2);
+
+	pkcsBlock[pkcsBlockLen-inputLen-1] = 0;               // separator
+	memcpy(pkcsBlock+pkcsBlockLen-inputLen, input, inputLen);
+}
+
+DecodingResult PKCS_SignaturePaddingScheme::Unpad(const byte *pkcsBlock, unsigned int pkcsBlockLen, byte *output) const
+{
+	unsigned int maxOutputLen = MaxUnpaddedLength(pkcsBlockLen);
+
+	// convert from bit length to byte length
+	if (pkcsBlockLen % 8 != 0)
+	{
+		if (pkcsBlock[0] != 0)
+			return DecodingResult();
+		pkcsBlock++;
+	}
+	pkcsBlockLen /= 8;
+
+	// Require block type 1.
+	if (pkcsBlock[0] != 1)
+		return DecodingResult();
+
+	// skip past the padding until we find the seperator
+	unsigned i=1;
+	while (i<pkcsBlockLen && pkcsBlock[i++])
+		if (pkcsBlock[i-1] != 0xff)     // not valid padding
+			return DecodingResult();
+	assert(i==pkcsBlockLen || pkcsBlock[i-1]==0);
+
+	unsigned int outputLen = pkcsBlockLen - i;
+	if (outputLen > maxOutputLen)
+		return DecodingResult();
+
+	memcpy (output, pkcsBlock+i, outputLen);
+	return DecodingResult(outputLen);
+}
+
+NAMESPACE_END