ObjXMPP  Diff

#define HMAC_IPAD 0x36
#define HMAC_OPAD 0x5c

@implementation XMPPSCRAMAuth
+ SCRAMAuthWithAuthcid: (OFString*)authcid
	      password: (OFString*)password
	    connection: (XMPPConnection*)connection
		  hash: (Class)hash
	 plusAvailable: (BOOL)plusAvailable
{
	return [[[self alloc] initWithAuthcid: authcid
				     password: password
				   connection: connection
					 hash: hash
				plusAvailable: plusAvailable] autorelease];
}

+ SCRAMAuthWithAuthzid: (OFString*)authzid
	       authcid: (OFString*)authcid
	      password: (OFString*)password
	    connection: (XMPPConnection*)connection
		  hash: (Class)hash
	 plusAvailable: (BOOL)plusAvailable
{
	return [[[self alloc] initWithAuthzid: authzid
				      authcid: authcid
				     password: password
				   connection: connection
					 hash: hash
				plusAvailable: plusAvailable] autorelease];
}

- initWithAuthcid: (OFString*)authcid
	 password: (OFString*)password
       connection: (XMPPConnection*)connection
	     hash: (Class)hash
    plusAvailable: (BOOL)plusAvailable
{
	return [self initWithAuthzid: nil
			     authcid: authcid
			    password: password
			  connection: connection
				hash: hash
		       plusAvailable: plusAvailable];
}

- initWithAuthzid: (OFString*)authzid
	  authcid: (OFString*)authcid
	 password: (OFString*)password
       connection: (XMPPConnection*)connection
	     hash: (Class)hash
    plusAvailable: (BOOL)plusAvailable
{
	self = [super initWithAuthzid: authzid
			      authcid: authcid
			     password: password];

	_hashType = hash;
	_plusAvailable = plusAvailable;
	_connection = [connection retain];

	return self;
}

- (void)dealloc
{
	[_GS2Header release];
	[_clientFirstMessageBare release];
	[_serverSignature release];
	[_cNonce release];
	[_connection release];

	[super dealloc];
}

- (void)setAuthzid: (OFString*)authzid
{
	OFString *old = _authzid;

	if (authzid) {
		OFMutableString *new = [[authzid mutableCopy] autorelease];
		[new replaceOccurrencesOfString: @"="
				     withString: @"=3D"];
		[new replaceOccurrencesOfString: @","
				     withString: @"=2C"];
		_authzid = [new retain];
	} else
		_authzid = nil;

	[old release];
}

- (void)setAuthcid: (OFString*)authcid
{
	OFString *old = _authcid;

	if (authcid) {
		OFMutableString *new = [[authcid mutableCopy] autorelease];
		[new replaceOccurrencesOfString: @"="
				     withString: @"=3D"];
		[new replaceOccurrencesOfString: @","
				     withString: @"=2C"];
		_authcid = [new retain];
	} else
		_authcid = nil;

	[old release];
}

- (OFDataArray*)initialMessage
{
	OFDataArray *ret = [OFDataArray dataArray];

	/* New authentication attempt, reset status */
	[_cNonce release];
	_cNonce = nil;
	[_GS2Header release];
	_GS2Header = nil;
	[_serverSignature release];
	_serverSignature = nil;
	_authenticated = NO;

	if (_authzid)
		_GS2Header = [[OFString alloc]
		    initWithFormat: @"%@,a=%@,",
				    (_plusAvailable ? @"p=tls-unique" : @"y"),
				    _authzid];
	else
		_GS2Header = (_plusAvailable ? @"p=tls-unique,," : @"y,,");

	_cNonce = [[self XMPP_genNonce] retain];

	[_clientFirstMessageBare release];
	_clientFirstMessageBare = nil;
	_clientFirstMessageBare = [[OFString alloc] initWithFormat: @"n=%@,r=%@",
								   _authcid,
								   _cNonce];

	[ret addItems: [_GS2Header UTF8String]
		count: [_GS2Header UTF8StringLength]];

	[ret addItems: [_clientFirstMessageBare UTF8String]
		count: [_clientFirstMessageBare UTF8StringLength]];

	return ret;
}

- (OFDataArray*)continueWithData: (OFDataArray*)data
{
	OFAutoreleasePool *pool = [[OFAutoreleasePool alloc] init];
	OFDataArray *ret;

	if (!_serverSignature)
		ret = [self XMPP_parseServerFirstMessage: data];
	else
		ret = [self XMPP_parseServerFinalMessage: data];

	[ret retain];
	[pool release];

	OFString *comp;
	enum {
		GOT_SNONCE    = 0x01,
		GOT_SALT      = 0x02,
		GOT_ITERCOUNT = 0x04
	} got = 0;

	hash = [[[_hashType alloc] init] autorelease];
	ret = [OFDataArray dataArray];
	authMessage = [OFDataArray dataArray];

	OFString *chal = [OFString stringWithUTF8String: [data items]
						 length: [data count] *
							 [data itemSize]];

	enumerator =
	    [[chal componentsSeparatedByString: @","] objectEnumerator];
	while ((comp = [enumerator nextObject]) != nil) {
		OFString *entry = [comp substringWithRange:
		    of_range(2, [comp length] - 2)];

		if ([comp hasPrefix: @"r="]) {
			if (![entry hasPrefix: _cNonce])
				@throw [XMPPAuthFailedException
				    exceptionWithClass: [self class]
					    connection: nil
						reason: @"Received wrong "
							@"nonce"];

			sNonce = entry;

	if (got != (GOT_SNONCE | GOT_SALT | GOT_ITERCOUNT))
		@throw [OFInvalidServerReplyException
		    exceptionWithClass: [self class]];

	// Add c=<base64(GS2Header+channelBindingData)>
	tmpArray = [OFDataArray dataArray];
	[tmpArray addItems: [_GS2Header UTF8String]
		     count: [_GS2Header UTF8StringLength]];
	if (_plusAvailable && [_connection encrypted]) {
		OFDataArray *channelBinding = [((SSLSocket*)[_connection socket])
		    channelBindingDataWithType: @"tls-unique"];
		[tmpArray addItems: [channelBinding items]
			     count: [channelBinding count]];
	}
	tmpString = [tmpArray stringByBase64Encoding];
	[ret addItems: "c="
		count: 2];

		count: [sNonce UTF8StringLength]];

	/*
	 * IETF RFC 5802:
	 * SaltedPassword := Hi(Normalize(password), salt, i)
	 */
	tmpArray = [OFDataArray dataArray];
	[tmpArray addItems: [_password UTF8String]
		     count: [_password UTF8StringLength]];

	saltedPassword = [self XMPP_hiWithData: tmpArray
					  salt: salt
				iterationCount: iterCount];

	/*
	 * IETF RFC 5802:
	 * AuthMessage := client-first-message-bare + "," +
	 *		  server-first-message + "," +
	 *		  client-final-message-without-proof
	 */
	[authMessage addItems: [_clientFirstMessageBare UTF8String]
			count: [_clientFirstMessageBare UTF8StringLength]];
	[authMessage addItem: ","];
	[authMessage addItems: [data items]
			count: [data count] * [data itemSize]];
	[authMessage addItem: ","];
	[authMessage addItems: [ret items]
			count: [ret count]];

				      data: tmpArray];

	/*
	 * IETF RFC 5802:
	 * StoredKey := H(ClientKey)
	 */
	[hash updateWithBuffer: (void*) clientKey
			length: [_hashType digestSize]];
	tmpArray = [OFDataArray dataArray];
	[tmpArray addItems: [hash digest]
		     count: [_hashType digestSize]];

	/*
	 * IETF RFC 5802:
	 * ClientSignature := HMAC(StoredKey, AuthMessage)
	 */
	clientSignature = [self XMPP_HMACWithKey: tmpArray
					    data: authMessage];

	/*
	 * IETF RFC 5802:
	 * ServerSignature := HMAC(ServerKey, AuthMessage)
	 */
	tmpArray = [OFDataArray dataArray];
	[tmpArray addItems: serverKey
		     count: [_hashType digestSize]];
	_serverSignature = [[OFDataArray alloc] init];
	[_serverSignature addItems: [self XMPP_HMACWithKey: tmpArray
						     data: authMessage]
			    count: [_hashType digestSize]];

	/*
	 * IETF RFC 5802:
	 * ClientProof := ClientKey XOR ClientSignature
	 */
	tmpArray = [OFDataArray dataArray];
	for (i = 0; i < [_hashType digestSize]; i++) {
		uint8_t c = clientKey[i] ^ clientSignature[i];
		[tmpArray addItem: &c];
	}

	// Add p=<base64(ClientProof)>
	[ret addItem: ","];
	[ret addItems: "p="

{
	OFString *mess, *value;

	/*
	 * server-final-message already received,
	 * we were just waiting for the last word from the server
	 */
	if (_authenticated)
		return nil;

	mess = [OFString stringWithUTF8String: [data items]
				       length: [data count] *
					       [data itemSize]];
	value = [mess substringWithRange: of_range(2, [mess length] - 2)];

	if ([mess hasPrefix: @"v="]) {
		if (![value isEqual: [_serverSignature stringByBase64Encoding]])
			@throw [XMPPAuthFailedException
			    exceptionWithClass: [self class]
				    connection: nil
					reason: @"Received wrong "
						@"ServerSignature"];
		_authenticated = YES;
	} else
		@throw [XMPPAuthFailedException exceptionWithClass: [self class]
							connection: nil
							    reason: value];

	return nil;
}

}

- (uint8_t*)XMPP_HMACWithKey: (OFDataArray*)key
			data: (OFDataArray*)data
{
	OFAutoreleasePool *pool = [[OFAutoreleasePool alloc] init];
	OFDataArray *k = [OFDataArray dataArray];
	size_t i, kSize, blockSize = [_hashType blockSize];
	uint8_t *kI = NULL, *kO = NULL;
	OFHash *hashI, *hashO;

	if ([key itemSize] * [key count] > blockSize) {
		hashI = [[[_hashType alloc] init] autorelease];
		[hashI updateWithBuffer: [key items]
				length: [key itemSize] * [key count]];
		[k addItems: [hashI digest]
		      count: [_hashType digestSize]];
	} else
		[k addItems: [key items]
		      count: [key itemSize] * [key count]];

	@try {
		kI = [self allocMemoryWithSize: blockSize];
		kO = [self allocMemoryWithSize: blockSize];

		kSize = [k count];
		memcpy(kI, [k items], kSize);
		memset(kI + kSize, 0, blockSize - kSize);
		memcpy(kO, kI, blockSize);

		for (i = 0; i < blockSize; i++) {
			kI[i] ^= HMAC_IPAD;
			kO[i] ^= HMAC_OPAD;
		}

		hashI = [[[_hashType alloc] init] autorelease];
		[hashI updateWithBuffer: (char*)kI
				 length: blockSize];
		[hashI updateWithBuffer: [data items]
				 length: [data itemSize] * [data count]];

		hashO = [[[_hashType alloc] init] autorelease];
		[hashO updateWithBuffer: (char*)kO
				 length: blockSize];
		[hashO updateWithBuffer: (char*)[hashI digest]
				 length: [_hashType digestSize]];
	} @finally {
		[self freeMemory: kI];
		[self freeMemory: kO];
	}

	[hashO retain];
	[pool release];

	return [[hashO autorelease] digest];
}

- (OFDataArray*)XMPP_hiWithData: (OFDataArray *)str
			   salt: (OFDataArray *)salt_
		 iterationCount: (intmax_t)i
{
	OFAutoreleasePool *pool = [[OFAutoreleasePool alloc] init];
	size_t digestSize = [_hashType digestSize];
	uint8_t *result = NULL, *u, *uOld;
	intmax_t j, k;
	OFDataArray *salty, *tmp, *ret;

	result = [self allocMemoryWithSize: digestSize];

	@try {