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Diffstat (limited to 'src-cryptopp/asn.cpp')
| -rw-r--r-- | src-cryptopp/asn.cpp | 595 |
1 files changed, 595 insertions, 0 deletions
diff --git a/src-cryptopp/asn.cpp b/src-cryptopp/asn.cpp new file mode 100644 index 0000000..3ebbaf7 --- /dev/null +++ b/src-cryptopp/asn.cpp @@ -0,0 +1,595 @@ +// asn.cpp - written and placed in the public domain by Wei Dai + +#include "pch.h" + +#ifndef CRYPTOPP_IMPORTS + +#include "asn.h" + +#include <iomanip> +#include <time.h> + +NAMESPACE_BEGIN(CryptoPP) +USING_NAMESPACE(std) + +/// DER Length +size_t DERLengthEncode(BufferedTransformation &bt, lword length) +{ + size_t i=0; + if (length <= 0x7f) + { + bt.Put(byte(length)); + i++; + } + else + { + bt.Put(byte(BytePrecision(length) | 0x80)); + i++; + for (int j=BytePrecision(length); j; --j) + { + bt.Put(byte(length >> (j-1)*8)); + i++; + } + } + return i; +} + +bool BERLengthDecode(BufferedTransformation &bt, lword &length, bool &definiteLength) +{ + byte b; + + if (!bt.Get(b)) + return false; + + if (!(b & 0x80)) + { + definiteLength = true; + length = b; + } + else + { + unsigned int lengthBytes = b & 0x7f; + + if (lengthBytes == 0) + { + definiteLength = false; + return true; + } + + definiteLength = true; + length = 0; + while (lengthBytes--) + { + if (length >> (8*(sizeof(length)-1))) + BERDecodeError(); // length about to overflow + + if (!bt.Get(b)) + return false; + + length = (length << 8) | b; + } + } + return true; +} + +bool BERLengthDecode(BufferedTransformation &bt, size_t &length) +{ + lword lw; + bool definiteLength; + if (!BERLengthDecode(bt, lw, definiteLength)) + BERDecodeError(); + if (!SafeConvert(lw, length)) + BERDecodeError(); + return definiteLength; +} + +void DEREncodeNull(BufferedTransformation &out) +{ + out.Put(TAG_NULL); + out.Put(0); +} + +void BERDecodeNull(BufferedTransformation &in) +{ + byte b; + if (!in.Get(b) || b != TAG_NULL) + BERDecodeError(); + size_t length; + if (!BERLengthDecode(in, length) || length != 0) + BERDecodeError(); +} + +/// ASN Strings +size_t DEREncodeOctetString(BufferedTransformation &bt, const byte *str, size_t strLen) +{ + bt.Put(OCTET_STRING); + size_t lengthBytes = DERLengthEncode(bt, strLen); + bt.Put(str, strLen); + return 1+lengthBytes+strLen; +} + +size_t DEREncodeOctetString(BufferedTransformation &bt, const SecByteBlock &str) +{ + return DEREncodeOctetString(bt, str.begin(), str.size()); +} + +size_t BERDecodeOctetString(BufferedTransformation &bt, SecByteBlock &str) +{ + byte b; + if (!bt.Get(b) || b != OCTET_STRING) + BERDecodeError(); + + size_t bc; + if (!BERLengthDecode(bt, bc)) + BERDecodeError(); + + str.resize(bc); + if (bc != bt.Get(str, bc)) + BERDecodeError(); + return bc; +} + +size_t BERDecodeOctetString(BufferedTransformation &bt, BufferedTransformation &str) +{ + byte b; + if (!bt.Get(b) || b != OCTET_STRING) + BERDecodeError(); + + size_t bc; + if (!BERLengthDecode(bt, bc)) + BERDecodeError(); + + bt.TransferTo(str, bc); + return bc; +} + +size_t DEREncodeTextString(BufferedTransformation &bt, const std::string &str, byte asnTag) +{ + bt.Put(asnTag); + size_t lengthBytes = DERLengthEncode(bt, str.size()); + bt.Put((const byte *)str.data(), str.size()); + return 1+lengthBytes+str.size(); +} + +size_t BERDecodeTextString(BufferedTransformation &bt, std::string &str, byte asnTag) +{ + byte b; + if (!bt.Get(b) || b != asnTag) + BERDecodeError(); + + size_t bc; + if (!BERLengthDecode(bt, bc)) + BERDecodeError(); + + SecByteBlock temp(bc); + if (bc != bt.Get(temp, bc)) + BERDecodeError(); + str.assign((char *)temp.begin(), bc); + return bc; +} + +/// ASN BitString +size_t DEREncodeBitString(BufferedTransformation &bt, const byte *str, size_t strLen, unsigned int unusedBits) +{ + bt.Put(BIT_STRING); + size_t lengthBytes = DERLengthEncode(bt, strLen+1); + bt.Put((byte)unusedBits); + bt.Put(str, strLen); + return 2+lengthBytes+strLen; +} + +size_t BERDecodeBitString(BufferedTransformation &bt, SecByteBlock &str, unsigned int &unusedBits) +{ + byte b; + if (!bt.Get(b) || b != BIT_STRING) + BERDecodeError(); + + size_t bc; + if (!BERLengthDecode(bt, bc)) + BERDecodeError(); + + byte unused; + if (!bt.Get(unused)) + BERDecodeError(); + unusedBits = unused; + str.resize(bc-1); + if ((bc-1) != bt.Get(str, bc-1)) + BERDecodeError(); + return bc-1; +} + +void DERReencode(BufferedTransformation &source, BufferedTransformation &dest) +{ + byte tag; + source.Peek(tag); + BERGeneralDecoder decoder(source, tag); + DERGeneralEncoder encoder(dest, tag); + if (decoder.IsDefiniteLength()) + decoder.TransferTo(encoder, decoder.RemainingLength()); + else + { + while (!decoder.EndReached()) + DERReencode(decoder, encoder); + } + decoder.MessageEnd(); + encoder.MessageEnd(); +} + +void OID::EncodeValue(BufferedTransformation &bt, word32 v) +{ + for (unsigned int i=RoundUpToMultipleOf(STDMAX(7U,BitPrecision(v)), 7U)-7; i != 0; i-=7) + bt.Put((byte)(0x80 | ((v >> i) & 0x7f))); + bt.Put((byte)(v & 0x7f)); +} + +size_t OID::DecodeValue(BufferedTransformation &bt, word32 &v) +{ + byte b; + size_t i=0; + v = 0; + while (true) + { + if (!bt.Get(b)) + BERDecodeError(); + i++; + v <<= 7; + v += b & 0x7f; + if (!(b & 0x80)) + return i; + } +} + +void OID::DEREncode(BufferedTransformation &bt) const +{ + assert(m_values.size() >= 2); + ByteQueue temp; + temp.Put(byte(m_values[0] * 40 + m_values[1])); + for (size_t i=2; i<m_values.size(); i++) + EncodeValue(temp, m_values[i]); + bt.Put(OBJECT_IDENTIFIER); + DERLengthEncode(bt, temp.CurrentSize()); + temp.TransferTo(bt); +} + +void OID::BERDecode(BufferedTransformation &bt) +{ + byte b; + if (!bt.Get(b) || b != OBJECT_IDENTIFIER) + BERDecodeError(); + + size_t length; + if (!BERLengthDecode(bt, length) || length < 1) + BERDecodeError(); + + if (!bt.Get(b)) + BERDecodeError(); + + length--; + m_values.resize(2); + m_values[0] = b / 40; + m_values[1] = b % 40; + + while (length > 0) + { + word32 v; + size_t valueLen = DecodeValue(bt, v); + if (valueLen > length) + BERDecodeError(); + m_values.push_back(v); + length -= valueLen; + } +} + +void OID::BERDecodeAndCheck(BufferedTransformation &bt) const +{ + OID oid(bt); + if (*this != oid) + BERDecodeError(); +} + +inline BufferedTransformation & EncodedObjectFilter::CurrentTarget() +{ + if (m_flags & PUT_OBJECTS) + return *AttachedTransformation(); + else + return TheBitBucket(); +} + +void EncodedObjectFilter::Put(const byte *inString, size_t length) +{ + if (m_nCurrentObject == m_nObjects) + { + AttachedTransformation()->Put(inString, length); + return; + } + + LazyPutter lazyPutter(m_queue, inString, length); + + while (m_queue.AnyRetrievable()) + { + switch (m_state) + { + case IDENTIFIER: + if (!m_queue.Get(m_id)) + return; + m_queue.TransferTo(CurrentTarget(), 1); + m_state = LENGTH; // fall through + case LENGTH: + { + byte b; + if (m_level > 0 && m_id == 0 && m_queue.Peek(b) && b == 0) + { + m_queue.TransferTo(CurrentTarget(), 1); + m_level--; + m_state = IDENTIFIER; + break; + } + ByteQueue::Walker walker(m_queue); + bool definiteLength; + if (!BERLengthDecode(walker, m_lengthRemaining, definiteLength)) + return; + m_queue.TransferTo(CurrentTarget(), walker.GetCurrentPosition()); + if (!((m_id & CONSTRUCTED) || definiteLength)) + BERDecodeError(); + if (!definiteLength) + { + if (!(m_id & CONSTRUCTED)) + BERDecodeError(); + m_level++; + m_state = IDENTIFIER; + break; + } + m_state = BODY; // fall through + } + case BODY: + m_lengthRemaining -= m_queue.TransferTo(CurrentTarget(), m_lengthRemaining); + + if (m_lengthRemaining == 0) + m_state = IDENTIFIER; + } + + if (m_state == IDENTIFIER && m_level == 0) + { + // just finished processing a level 0 object + ++m_nCurrentObject; + + if (m_flags & PUT_MESSANGE_END_AFTER_EACH_OBJECT) + AttachedTransformation()->MessageEnd(); + + if (m_nCurrentObject == m_nObjects) + { + if (m_flags & PUT_MESSANGE_END_AFTER_ALL_OBJECTS) + AttachedTransformation()->MessageEnd(); + + if (m_flags & PUT_MESSANGE_SERIES_END_AFTER_ALL_OBJECTS) + AttachedTransformation()->MessageSeriesEnd(); + + m_queue.TransferAllTo(*AttachedTransformation()); + return; + } + } + } +} + +BERGeneralDecoder::BERGeneralDecoder(BufferedTransformation &inQueue, byte asnTag) + : m_inQueue(inQueue), m_finished(false) +{ + Init(asnTag); +} + +BERGeneralDecoder::BERGeneralDecoder(BERGeneralDecoder &inQueue, byte asnTag) + : m_inQueue(inQueue), m_finished(false) +{ + Init(asnTag); +} + +void BERGeneralDecoder::Init(byte asnTag) +{ + byte b; + if (!m_inQueue.Get(b) || b != asnTag) + BERDecodeError(); + + if (!BERLengthDecode(m_inQueue, m_length, m_definiteLength)) + BERDecodeError(); + + if (!m_definiteLength && !(asnTag & CONSTRUCTED)) + BERDecodeError(); // cannot be primitive and have indefinite length +} + +BERGeneralDecoder::~BERGeneralDecoder() +{ + try // avoid throwing in constructor + { + if (!m_finished) + MessageEnd(); + } + catch (...) + { + } +} + +bool BERGeneralDecoder::EndReached() const +{ + if (m_definiteLength) + return m_length == 0; + else + { // check end-of-content octets + word16 i; + return (m_inQueue.PeekWord16(i)==2 && i==0); + } +} + +byte BERGeneralDecoder::PeekByte() const +{ + byte b; + if (!Peek(b)) + BERDecodeError(); + return b; +} + +void BERGeneralDecoder::CheckByte(byte check) +{ + byte b; + if (!Get(b) || b != check) + BERDecodeError(); +} + +void BERGeneralDecoder::MessageEnd() +{ + m_finished = true; + if (m_definiteLength) + { + if (m_length != 0) + BERDecodeError(); + } + else + { // remove end-of-content octets + word16 i; + if (m_inQueue.GetWord16(i) != 2 || i != 0) + BERDecodeError(); + } +} + +size_t BERGeneralDecoder::TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel, bool blocking) +{ + if (m_definiteLength && transferBytes > m_length) + transferBytes = m_length; + size_t blockedBytes = m_inQueue.TransferTo2(target, transferBytes, channel, blocking); + ReduceLength(transferBytes); + return blockedBytes; +} + +size_t BERGeneralDecoder::CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end, const std::string &channel, bool blocking) const +{ + if (m_definiteLength) + end = STDMIN(m_length, end); + return m_inQueue.CopyRangeTo2(target, begin, end, channel, blocking); +} + +lword BERGeneralDecoder::ReduceLength(lword delta) +{ + if (m_definiteLength) + { + if (m_length < delta) + BERDecodeError(); + m_length -= delta; + } + return delta; +} + +DERGeneralEncoder::DERGeneralEncoder(BufferedTransformation &outQueue, byte asnTag) + : m_outQueue(outQueue), m_finished(false), m_asnTag(asnTag) +{ +} + +DERGeneralEncoder::DERGeneralEncoder(DERGeneralEncoder &outQueue, byte asnTag) + : m_outQueue(outQueue), m_finished(false), m_asnTag(asnTag) +{ +} + +DERGeneralEncoder::~DERGeneralEncoder() +{ + try // avoid throwing in constructor + { + if (!m_finished) + MessageEnd(); + } + catch (...) + { + } +} + +void DERGeneralEncoder::MessageEnd() +{ + m_finished = true; + lword length = CurrentSize(); + m_outQueue.Put(m_asnTag); + DERLengthEncode(m_outQueue, length); + TransferTo(m_outQueue); +} + +// ************************************************************* + +void X509PublicKey::BERDecode(BufferedTransformation &bt) +{ + BERSequenceDecoder subjectPublicKeyInfo(bt); + BERSequenceDecoder algorithm(subjectPublicKeyInfo); + GetAlgorithmID().BERDecodeAndCheck(algorithm); + bool parametersPresent = algorithm.EndReached() ? false : BERDecodeAlgorithmParameters(algorithm); + algorithm.MessageEnd(); + + BERGeneralDecoder subjectPublicKey(subjectPublicKeyInfo, BIT_STRING); + subjectPublicKey.CheckByte(0); // unused bits + BERDecodePublicKey(subjectPublicKey, parametersPresent, (size_t)subjectPublicKey.RemainingLength()); + subjectPublicKey.MessageEnd(); + subjectPublicKeyInfo.MessageEnd(); +} + +void X509PublicKey::DEREncode(BufferedTransformation &bt) const +{ + DERSequenceEncoder subjectPublicKeyInfo(bt); + + DERSequenceEncoder algorithm(subjectPublicKeyInfo); + GetAlgorithmID().DEREncode(algorithm); + DEREncodeAlgorithmParameters(algorithm); + algorithm.MessageEnd(); + + DERGeneralEncoder subjectPublicKey(subjectPublicKeyInfo, BIT_STRING); + subjectPublicKey.Put(0); // unused bits + DEREncodePublicKey(subjectPublicKey); + subjectPublicKey.MessageEnd(); + + subjectPublicKeyInfo.MessageEnd(); +} + +void PKCS8PrivateKey::BERDecode(BufferedTransformation &bt) +{ + BERSequenceDecoder privateKeyInfo(bt); + word32 version; + BERDecodeUnsigned<word32>(privateKeyInfo, version, INTEGER, 0, 0); // check version + + BERSequenceDecoder algorithm(privateKeyInfo); + GetAlgorithmID().BERDecodeAndCheck(algorithm); + bool parametersPresent = algorithm.EndReached() ? false : BERDecodeAlgorithmParameters(algorithm); + algorithm.MessageEnd(); + + BERGeneralDecoder octetString(privateKeyInfo, OCTET_STRING); + BERDecodePrivateKey(octetString, parametersPresent, (size_t)privateKeyInfo.RemainingLength()); + octetString.MessageEnd(); + + if (!privateKeyInfo.EndReached()) + BERDecodeOptionalAttributes(privateKeyInfo); + privateKeyInfo.MessageEnd(); +} + +void PKCS8PrivateKey::DEREncode(BufferedTransformation &bt) const +{ + DERSequenceEncoder privateKeyInfo(bt); + DEREncodeUnsigned<word32>(privateKeyInfo, 0); // version + + DERSequenceEncoder algorithm(privateKeyInfo); + GetAlgorithmID().DEREncode(algorithm); + DEREncodeAlgorithmParameters(algorithm); + algorithm.MessageEnd(); + + DERGeneralEncoder octetString(privateKeyInfo, OCTET_STRING); + DEREncodePrivateKey(octetString); + octetString.MessageEnd(); + + DEREncodeOptionalAttributes(privateKeyInfo); + privateKeyInfo.MessageEnd(); +} + +void PKCS8PrivateKey::BERDecodeOptionalAttributes(BufferedTransformation &bt) +{ + DERReencode(bt, m_optionalAttributes); +} + +void PKCS8PrivateKey::DEREncodeOptionalAttributes(BufferedTransformation &bt) const +{ + m_optionalAttributes.CopyTo(bt); +} + +NAMESPACE_END + +#endif |