/*

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

#include "encdec.h"

#include "x509utils.h"

#include "logger.h"

//

// TKeyIdentifier

//

void EncodeHuman(REncodeWriteStream& aStream,const KeyIdentifierObject  &aKeyId)

{

	if(aKeyId.iAutoKey)

		{

		aStream.WriteCStr("auto");

		if(aKeyId.iHash.Length() == 0)

			{

			return; // Empty value so no point in including it in a comment...

			}

		if(!aStream.Verbose())

			{

			return; // auto, and not in verbose mode so do not write value in comment

			}

		aStream.WriteCStr(" # ");

		}

	aStream.WriteByte('\'');

	const TUint8 *ptr = aKeyId.iHash.Ptr();

	TInt len = aKeyId.iHash.Length();

	while(len--)

		{

		TUint8 byte = *ptr++;

		TUint8 buf[2];

		TUint8 ch = ((byte & 0xf0) >> 4);

		ch = (ch<=9) ? (ch +'0') : (ch - 10 +'A');

		// Write MSB char of byte

		buf[0] = ch;

		ch = (byte & 0x0f);

		ch = (ch<=9) ? (ch +'0') : (ch - 10 +'A');

		// Write LSB char of byte

		buf[1] = ch;

		aStream.WriteBin(buf, sizeof(buf));

		if(len)

			{

			aStream.WriteByte(':');

			}

		}

	aStream.WriteByte('\'');

}

void DecodeHuman(RDecodeReadStream& aStream, KeyIdentifierObject &aKeyId)

{

	aStream.ReadNextToken();

	std::string tok = aStream.Token();

	if(tok == "auto")

		{

		aKeyId.iAutoKey = true;

		aKeyId.iHash.SetLength(0);

		return;

		}

	aKeyId.iAutoKey = false;

	if((tok[0] != '\'') || (tok[tok.size()-1] != '\'') || (tok.size() < 2))

		{

		dbg << Log::Indent() << "KeyIdentifier not enclosed in single quotes, or contains spaces - " << tok << Log::Endl();

		FatalError();

		}

	tok.erase(0,1);

	tok.erase(tok.size()-1,1);

	if(tok.size() == 0)

		{

		aKeyId.iHash.SetLength(0);

		return;

		}

	if(TInt(tok.size()) != (aKeyId.iHash.MaxLength()*2) + (aKeyId.iHash.MaxLength()-1))

		{

		dbg << Log::Indent() << "WARNING: KeyIdentifier length not " << aKeyId.iHash.MaxLength()*2 << " hex digits" << Log::Endl();

		dbg << Log::Indent() << "KeyIdentifier is '" << tok << "'" << Log::Endl();

		}

	bool bad = false;

	TInt bytesRead = 0;

	const char *hexDigit = tok.data();

	TInt charsToRead = tok.size();

	TUint8 *dest = const_cast<TUint8 *>(aKeyId.iHash.Ptr());

	while(charsToRead)

		{

		// Read MSB char

		TUint8 byte = fromHex(*hexDigit++);

		byte <<= 4;

		--charsToRead;

		// Read LSB char

		if(charsToRead == 0)

			{

			bad = true;

			break;

			}

		byte |= fromHex(*hexDigit++);

		--charsToRead;

		// Save decoded byte

		*dest++ = byte;

		++bytesRead;

		if(charsToRead != 0)

			{

			// Consume : separator

			if(*hexDigit++ != ':')

				{

				bad = true;

				break;

				}

			--charsToRead;

			}

		}

	if(bytesRead > aKeyId.iHash.MaxLength())

		{

		dbg << Log::Indent() << "Key Identifiier is too long" << Log::Endl();

		bad = true;

		}

	if(bad)

		{

		dbg << Log::Indent() << "KeyIdentifier invalid - It should be a single quoted string containing a series of 0 or more 2 digit hex numbers separated by : chars." << Log::Endl();

		dbg << Log::Indent() << "This field should normally be set to auto or omitted" << Log::Endl();

		dbg << Log::Indent() << "KeyIdentifier is '" << tok << "'" << Log::Endl();

		FatalError();

		}

	aKeyId.iHash.SetLength(bytesRead);

	return;

}

RWriteStream& operator<<(RWriteStream& aStream,const KeyIdentifierObject& aKeyId)

{

	aStream << aKeyId.iHash;

	return aStream;

}

RReadStream& operator>>(RReadStream& aStream, KeyIdentifierObject& aKeyId)

{

	aKeyId.iAutoKey = false;

	aStream >> aKeyId.iHash;

	return aStream;

}

// It is illegal to pass a "X **" ptr to a function taking a "const X

// **" argument. This is because the function could change the callers

// pointer to point at a const object which the caller might then

// accidentally write to!

//

// Unfortunately openssl 0.9.7* defines d2i_X509 to take an "unsigned

// char **" and 0.9.8 takes "const unsigned char **", so neither

// caller choice will compile for both....

#if OPENSSL_VERSION_NUMBER >= 0x00908000L

#define D2I_CONST const

#else

#define D2I_CONST

#endif

bool X509SubjectKeyId(EUseCertificateExtension aUseExtension, bool aUseRfc3280Algorithm,

					  bool aIsCa, const std::string &aCert, 

					  std::string &aSubject, TKeyIdentifier &aSubjectKeyId)

{

	bool done = false;

	prog << Log::Indent() << "X509SubjectKeyId - aUseExtension " << aUseExtension << " aUseRfc3280Algorithm " << aUseRfc3280Algorithm << " :-" << Log::Endl();

	AutoIndent ai(prog); // IncIndent, will DecIndent when it leaves scope

	// decode DER certificate into X509 structure

	D2I_CONST unsigned char *p = (D2I_CONST unsigned char *)aCert.data();

	X509 *x509 = d2i_X509(NULL, &p, aCert.size());

	if(!x509 || ((const char *)p != aCert.data() + aCert.size()))

		{

		dbg << Log::Indent() << "openssl failed to decode certificate" << Log::Endl();

		FatalError();

		}

	// Return the Subject Name

	prog << Log::Indent() << "Cert subject is '" << x509->name << "'" << Log::Endl();

	aSubject = std::string(x509->name);

	TUint32 ver = X509_get_version(x509);

	prog << Log::Indent() << "Cert version is '" << ver << "'" << Log::Endl();

	// if the ver is a v1 or v2 type then there is no way of knowing which is a CA, treat all certs as CA as done in the certificate recognizer.

	bool treatAsCa = false;  

	if ( ver < 3 || aIsCa )

		{

		treatAsCa = true;

		}

	if(treatAsCa && aUseExtension)

		{

		// Attempt to read Subject Key Id extension

		ASN1_OCTET_STRING *subKeyId = (ASN1_OCTET_STRING *) X509_get_ext_d2i(x509, NID_subject_key_identifier, NULL, NULL);

		if(subKeyId)

			{

			prog << Log::Indent() << "Found SubjectKeyId extension" << Log::Endl();

			if(subKeyId->length <= aSubjectKeyId.MaxLength())

				{

				aSubjectKeyId = TPtrC8(subKeyId->data, subKeyId->length);

				done = true;

				}

			else

				{

				prog << Log::Indent() << "but SubjectKeyId > 160 bits so ignoring it" << Log::Endl();

				}

			ASN1_OCTET_STRING_free(subKeyId);

			}

		}

	if(!done)

		{

		// Subject Key Id extension was ignored, missing or too long...

		if(aUseRfc3280Algorithm)

			{

			// We do not need to decode the public key just hash its

			// data as per rfc3280 4.2.1.2 method 1

			prog << Log::Indent() << "Calculating SubjectKeyId using RFC3280 4.2.1.2 method 1" << Log::Endl();

			unsigned char sha1hash[SHA_DIGEST_LENGTH];

			SHA1(x509->cert_info->key->public_key->data, x509->cert_info->key->public_key->length,

				 sha1hash);

			aSubjectKeyId = TPtrC8(sha1hash, SHA_DIGEST_LENGTH);

			done = true;

			}

		else

			{

			// Calculate SubjectKeyId via Symbian algorithm

			prog << Log::Indent() << "Calculating SubjectKeyId using Symbian algorithm" << Log::Endl();

			EVP_PKEY *key = X509_PUBKEY_get(x509->cert_info->key);

			if(!key)

				{

				dbg << Log::Indent() << "openssl failed to decode certificate public key" << Log::Endl();

				FatalError();

				}

			switch(key->type)

				{

				case EVP_PKEY_RSA:

					{

					TUint32 len = key->pkey.rsa->n->top*sizeof(BN_ULONG);

					TUint8 *buf = new TUint8[len];

					for(TUint32 i=0; i<len; ++i)

						{

						buf[i] = ((TUint8 *)key->pkey.rsa->n->d)[len-i-1];

						}

					unsigned char sha1hash[SHA_DIGEST_LENGTH];

					SHA1(buf, len, sha1hash);

					delete [] buf;

					aSubjectKeyId = TPtrC8(sha1hash, SHA_DIGEST_LENGTH);

					done = true;

					break;

					}

				case EVP_PKEY_DSA:

					{

					TUint32 len = key->pkey.dsa->pub_key->top*sizeof(BN_ULONG);

					TUint8 *buf = new TUint8[len];

					for(TUint32 i=0; i<len; ++i)

						{

						buf[i] = ((TUint8 *)key->pkey.dsa->pub_key->d)[len-i-1];

						}

					unsigned char sha1hash[SHA_DIGEST_LENGTH];

					SHA1(buf, len, sha1hash);

					delete [] buf;

					aSubjectKeyId = TPtrC8(sha1hash, SHA_DIGEST_LENGTH);

					done = true;

					break;

					}

				default:

					// Unknown public key type.

					prog << Log::Indent() << "Unknown public key type " << key->type << Log::Endl();

					break;

				}

			EVP_PKEY_free(key);

			}

		}

	X509_free(x509);

	return done;

}

bool X509IssuerKeyId(EUseCertificateExtension aUseExtension,

					 const TUint8 *aCert, TUint32 aCertLength, 

					 std::string &aIssuer, TKeyIdentifier &aIssuerKeyId)

{	

	prog << Log::Indent() << "X509IssuerKeyId :-" << Log::Endl();

	AutoIndent ai(prog); // IncIndent, will DecIndent when it leaves scope

	bool done = false;

	// decode DER certificate into X509 structure

	D2I_CONST unsigned char *p = (D2I_CONST unsigned char *)aCert;

	X509 *x509 = d2i_X509(NULL, &p, aCertLength);

	if(!x509 || (p != aCert+aCertLength))

		{

		dbg << Log::Indent() << "openssl failed to decode certificate" << Log::Endl();

		FatalError();

		}

	// Return the Subject Name

	prog << Log::Indent() << "Cert subject is '" << x509->name << "'" << Log::Endl();

	char *issuerOne = X509_NAME_oneline(X509_get_issuer_name(x509),0,0);

	prog << Log::Indent() << "Cert issuer is '" << issuerOne << "'" << Log::Endl();

	aIssuer = issuerOne;

	OPENSSL_free(issuerOne);

	if(aUseExtension)

		{

		// Attempt to read Subject Key Id extension

		AUTHORITY_KEYID *authKeyId = (AUTHORITY_KEYID *) X509_get_ext_d2i(x509, NID_authority_key_identifier, NULL, NULL);

		if(authKeyId)

			{

			prog << Log::Indent() << "Found AuthorityKeyId extension" << Log::Endl();

			if(authKeyId->keyid)

				{

				if(authKeyId->keyid->length <= aIssuerKeyId.MaxLength())

					{

					aIssuerKeyId = TPtrC8(authKeyId->keyid->data, authKeyId->keyid->length);

					done = true;

					}

				else

					{

					prog << Log::Indent() << "but AuthroityKeyId > 160 bits so ignoring it" << Log::Endl();

					}

				}

			else

				{

				prog << Log::Indent() << "but it does not include a key id, so ignoring it" << Log::Endl();

				}

			AUTHORITY_KEYID_free(authKeyId);

			}

		}

	X509_free(x509);

	return done;

}

void Der2Pem(const std::string &aDerCert, std::string &aPemCert)

{

	prog << Log::Indent() << "Converting DER to PEM:-" << Log::Endl();

	AutoIndent ai(prog); // IncIndent, will DecIndent when it leaves scope

	// decode DER certificate into X509 structure

	D2I_CONST unsigned char *p = (D2I_CONST unsigned char *)aDerCert.data();

	X509 *x509 = d2i_X509(NULL, &p, aDerCert.size());

	if(!x509 || ((const char *)p != aDerCert.data()+aDerCert.size()))

		{

		dbg << Log::Indent() << "openssl failed to decode certificate" << Log::Endl();

		FatalError();

		}

	BIO *memBio = BIO_new(BIO_s_mem());

BULLSEYE_OFF

	if(!memBio)

		{

		dbg << Log::Indent() << "openssl failed to create BIO" << Log::Endl();

		FatalError();

		}

	if(!PEM_write_bio_X509(memBio, x509))

		{

		dbg << Log::Indent() << "openssl failed to convert to PEM" << Log::Endl();

		FatalError();

		}

BULLSEYE_RESTORE

	long pemCertLen = 0;

	char *pemCertData = 0;

	pemCertLen = BIO_get_mem_data(memBio, &pemCertData);

	// Return the PEM cert

	aPemCert.assign(pemCertData, pemCertLen);

	BIO_free(memBio);

	X509_free(x509);

	prog << Log::Indent() << "Conversion ok" << Log::Endl();

	return;

}

static const char utf8Header[] = 

	{

		0xef, 0xbb, 0xbf

	};

bool Pem2Der(const std::string &aPemCert, std::string &aDerCert)

{

	prog << Log::Indent() << "Try PEM to DER coversion :-" << Log::Endl();

	AutoIndent ai(prog); // IncIndent, will DecIndent when it leaves scope

	TUint32 pemLength=aPemCert.size();

	const char *pemData=aPemCert.data();

	if((pemLength >= 3) && (memcmp(aPemCert.data(), utf8Header, sizeof(utf8Header)) == 0))

		{

		// PEM cert has a UTF8 header, so strip it

		prog << Log::Indent() << "Certificate data file has a UTF-8 header" << Log::Endl();

		pemLength -= sizeof(utf8Header);

		pemData += sizeof(utf8Header);

		}

	//

	// Read PEM to internal

	//

	BIO *memBioIn = BIO_new_mem_buf((void *)pemData, pemLength);

BULLSEYE_OFF

	if(!memBioIn)

		{

		dbg << Log::Indent() << "openssl failed to create BIO for reading PEM" << Log::Endl();

		FatalError();

		}

BULLSEYE_RESTORE

	X509 *x509 = PEM_read_bio_X509(memBioIn, NULL, 0, NULL);

	if(!x509)

		{

		prog << Log::Indent() << "Conversion failed - presumably DER" << Log::Endl();

		return false;

		}

	BIO_free(memBioIn);

    memBioIn = 0;

	//

	// Write internal to DER

	//

	unsigned char *derCert = 0;

	int derLen = i2d_X509(x509, &derCert);

	if(derLen <=0 )

		{

		dbg << Log::Indent() << "openssl failed to convert to DER" << Log::Endl();

		FatalError();

		}

	// Return the DER cert

	aDerCert.assign((char *)derCert, derLen);

	X509_free(x509);

	prog << Log::Indent() << "Conversion ok" << Log::Endl();

	return true;

}

// End of file