ObjFW  Artifact [0ef7b9c0c4]

Artifact 0ef7b9c0c4e185dc74b0a32eb83bddc2e29f8c202d68fa82591006ec8e939fd0:

• File src/OFHTTPClient.m — part of check-in [d30efa8bbf] at 2021-11-13 13:04:13 on branch trunk — Completely rework the TLS/SSL API

  The previous API could never work cleanly and would always require
  hacks, as it needed intercepting all interactions of OFTCPSocket with
  the raw socket and did not work at all if the OFTCPSocket had anything
  in its read buffer before starting the TLS handshake. This also could
  not be fixed easily, as it would have required the object to contain two
  read buffers, one for the unencrypted connection and one for the
  encrypted connection. There was also no clean way to perform the
  handshake in a non-blocking way.

  The new API is a lot cleaner and requires none of the hacks, but using
  it requires slightly more work. But this is more than made up for by
  making a fully asynchronous handshake possible. It uses the concept of a
  stream wrapping another stream, meaning the entire connecting part is
  being handled by OFTCPSocket and then the connected socket is passed off
  to OFTLSStream to wrap it. This also makes for a lot cleaner separation
  of concerns. (user: js, size: 30982) [annotate] [blame] [check-ins using]

/*
 * Copyright (c) 2008-2021 Jonathan Schleifer <js@nil.im>
 *
 * All rights reserved.
 *
 * This file is part of ObjFW. It may be distributed under the terms of the
 * Q Public License 1.0, which can be found in the file LICENSE.QPL included in
 * the packaging of this file.
 *
 * Alternatively, it may be distributed under the terms of the GNU General
 * Public License, either version 2 or 3, which can be found in the file
 * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
 * file.
 */

#define OF_HTTPCLIENT_M

#include "config.h"

#include <errno.h>
#include <string.h>

#import "OFHTTPClient.h"
#import "OFData.h"
#import "OFDictionary.h"
#import "OFHTTPRequest.h"
#import "OFHTTPResponse.h"
#import "OFKernelEventObserver.h"
#import "OFNumber.h"
#import "OFRunLoop.h"
#import "OFString.h"
#import "OFTCPSocket.h"
#import "OFTLSStream.h"
#import "OFURL.h"

#import "OFAlreadyConnectedException.h"
#import "OFHTTPRequestFailedException.h"
#import "OFInvalidArgumentException.h"
#import "OFInvalidEncodingException.h"
#import "OFInvalidFormatException.h"
#import "OFInvalidServerReplyException.h"
#import "OFNotImplementedException.h"
#import "OFNotOpenException.h"
#import "OFOutOfMemoryException.h"
#import "OFOutOfRangeException.h"
#import "OFTruncatedDataException.h"
#import "OFUnsupportedProtocolException.h"
#import "OFUnsupportedVersionException.h"
#import "OFWriteFailedException.h"

static const unsigned int defaultRedirects = 10;

OF_DIRECT_MEMBERS
@interface OFHTTPClientRequestHandler: OFObject <OFTCPSocketDelegate,
    OFTLSStreamDelegate>
{
@public
	OFHTTPClient *_client;
	OFHTTPRequest *_request;
	unsigned int _redirects;
	bool _firstLine;
	OFString *_version;
	short _status;
	OFMutableDictionary OF_GENERIC(OFString *, OFString *) *_serverHeaders;
}

- (instancetype)initWithClient: (OFHTTPClient *)client
		       request: (OFHTTPRequest *)request
		     redirects: (unsigned int)redirects;
- (void)start;
- (void)closeAndReconnect;
@end

OF_DIRECT_MEMBERS
@interface OFHTTPClientRequestBodyStream: OFStream <OFReadyForWritingObserving>
{
	OFHTTPClientRequestHandler *_handler;
	OFStream *_stream;
	bool _chunked;
	unsigned long long _toWrite;
	bool _atEndOfStream;
}

- (instancetype)initWithHandler: (OFHTTPClientRequestHandler *)handler
			 stream: (OFStream *)stream;
@end

OF_DIRECT_MEMBERS
@interface OFHTTPClientResponse: OFHTTPResponse <OFReadyForReadingObserving>
{
	OFStream *_stream;
	bool _hasContentLength, _chunked, _keepAlive;
	bool _atEndOfStream, _setAtEndOfStream;
	long long _toRead;
}

@property (nonatomic, setter=of_setKeepAlive:) bool of_keepAlive;

- (instancetype)initWithStream: (OFStream *)stream;
@end

OF_DIRECT_MEMBERS
@interface OFHTTPClientSyncPerformer: OFObject <OFHTTPClientDelegate>
{
	OFHTTPClient *_client;
	OFObject <OFHTTPClientDelegate> *_delegate;
	OFHTTPResponse *_response;
}

- (instancetype)initWithClient: (OFHTTPClient *)client;
- (OFHTTPResponse *)performRequest: (OFHTTPRequest *)request
			 redirects: (unsigned int)redirects;
@end

static OFString *
constructRequestString(OFHTTPRequest *request)
{
	void *pool = objc_autoreleasePoolPush();
	OFHTTPRequestMethod method = request.method;
	OFURL *URL = request.URL;
	OFString *path;
	OFString *user = URL.user, *password = URL.password;
	OFMutableString *requestString;
	OFMutableDictionary OF_GENERIC(OFString *, OFString *) *headers;
	bool hasContentLength, chunked;
	OFEnumerator OF_GENERIC(OFString *) *keyEnumerator, *objectEnumerator;
	OFString *key, *object;

	if (URL.path != nil)
		path = URL.URLEncodedPath;
	else
		path = @"/";

	requestString = [OFMutableString stringWithFormat:
	    @"%s %@", OFHTTPRequestMethodName(method), path];

	if (URL.query != nil) {
		[requestString appendString: @"?"];
		[requestString appendString: URL.URLEncodedQuery];
	}

	[requestString appendString: @" HTTP/"];
	[requestString appendString: request.protocolVersionString];
	[requestString appendString: @"\r\n"];

	headers = [[request.headers mutableCopy] autorelease];
	if (headers == nil)
		headers = [OFMutableDictionary dictionary];

	if ([headers objectForKey: @"Host"] == nil) {
		OFNumber *port = URL.port;

		if (port != nil) {
			OFString *host = [OFString stringWithFormat:
			    @"%@:%@", URL.URLEncodedHost, port];

			[headers setObject: host forKey: @"Host"];
		} else
			[headers setObject: URL.URLEncodedHost forKey: @"Host"];
	}

	if ((user.length > 0 || password.length > 0) &&
	    [headers objectForKey: @"Authorization"] == nil) {
		OFMutableData *authorizationData = [OFMutableData data];
		OFString *authorization;

		[authorizationData addItems: user.UTF8String
				      count: user.UTF8StringLength];
		[authorizationData addItem: ":"];
		[authorizationData addItems: password.UTF8String
				      count: password.UTF8StringLength];

		authorization = [OFString stringWithFormat:
		    @"Basic %@", authorizationData.stringByBase64Encoding];

		[headers setObject: authorization forKey: @"Authorization"];
	}

	if ([headers objectForKey: @"User-Agent"] == nil)
		[headers setObject: @"Something using ObjFW "
				    @"<https://objfw.nil.im/>"
			    forKey: @"User-Agent"];

	if (request.protocolVersion.major == 1 &&
	    request.protocolVersion.minor == 0 &&
	    [headers objectForKey: @"Connection"] == nil)
		[headers setObject: @"keep-alive" forKey: @"Connection"];

	hasContentLength = ([headers objectForKey: @"Content-Length"] != nil);
	chunked = [[headers objectForKey: @"Transfer-Encoding"]
	    isEqual: @"chunked"];

	if ((hasContentLength || chunked) &&
	    [headers objectForKey: @"Content-Type"] == nil)
		[headers setObject: @"application/x-www-form-"
				    @"urlencoded; charset=UTF-8"
			    forKey: @"Content-Type"];

	keyEnumerator = [headers keyEnumerator];
	objectEnumerator = [headers objectEnumerator];

	while ((key = [keyEnumerator nextObject]) != nil &&
	    (object = [objectEnumerator nextObject]) != nil)
		[requestString appendFormat: @"%@: %@\r\n", key, object];

	[requestString appendString: @"\r\n"];

	[requestString retain];

	objc_autoreleasePoolPop(pool);

	return [requestString autorelease];
}

static OF_INLINE void
normalizeKey(char *str_)
{
	unsigned char *str = (unsigned char *)str_;
	bool firstLetter = true;

	while (*str != '\0') {
		if (!OFASCIIIsAlpha(*str)) {
			firstLetter = true;
			str++;
			continue;
		}

		*str = (firstLetter
		    ? OFASCIIToUpper(*str) : OFASCIIToLower(*str));

		firstLetter = false;
		str++;
	}
}

static bool
defaultShouldFollow(OFHTTPRequestMethod method, short statusCode)
{
	bool follow;

	/*
	 * 301, 302 and 307 should only redirect with user confirmation if the
	 * request method is not GET or HEAD. Asking the delegate and getting
	 * true returned is considered user confirmation.
	 */
	if (method == OFHTTPRequestMethodGet ||
	    method == OFHTTPRequestMethodHead)
		follow = true;
	/* 303 should always be redirected and converted to a GET request. */
	else if (statusCode == 303)
		follow = true;
	else
		follow = false;

	return follow;
}

@implementation OFHTTPClientRequestHandler
- (instancetype)initWithClient: (OFHTTPClient *)client
		       request: (OFHTTPRequest *)request
		     redirects: (unsigned int)redirects
{
	self = [super init];

	@try {
		_client = [client retain];
		_request = [request retain];
		_redirects = redirects;
		_serverHeaders = [[OFMutableDictionary alloc] init];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[_client release];
	[_request release];
	[_version release];
	[_serverHeaders release];

	[super dealloc];
}

- (void)raiseException: (id)exception
{
	[_client close];
	_client->_inProgress = false;

	[_client->_delegate client: _client
		 didPerformRequest: _request
			  response: nil
			 exception: exception];
}

- (void)createResponseWithStreamOrThrow: (OFStream *)stream
{
	OFURL *URL = _request.URL;
	OFHTTPClientResponse *response;
	OFString *connectionHeader;
	bool keepAlive;
	OFString *location;
	id exception;

	response = [[[OFHTTPClientResponse alloc] initWithStream: stream]
	    autorelease];
	response.protocolVersionString = _version;
	response.statusCode = _status;
	response.headers = _serverHeaders;

	connectionHeader = [_serverHeaders objectForKey: @"Connection"];
	if ([_version isEqual: @"1.1"]) {
		if (connectionHeader != nil)
			keepAlive = [connectionHeader isEqual: @"close"];
		else
			keepAlive = true;
	} else {
		if (connectionHeader != nil)
			keepAlive = ([connectionHeader caseInsensitiveCompare:
			    @"keep-alive"] == OFOrderedSame);
		else
			keepAlive = false;
	}

	if (keepAlive) {
		response.of_keepAlive = true;

		_client->_stream = [stream retain];
		_client->_lastURL = [URL copy];
		_client->_lastWasHEAD =
		    (_request.method == OFHTTPRequestMethodHead);
		_client->_lastResponse = [response retain];
	}

	if (_redirects > 0 && (_status == 301 || _status == 302 ||
	    _status == 303 || _status == 307) &&
	    (location = [_serverHeaders objectForKey: @"Location"]) != nil) {
		bool follow = true;
		OFURL *newURL;
		OFString *newURLScheme;

		newURL = [OFURL URLWithString: location
				relativeToURL: URL];
		newURLScheme = newURL.scheme;

		if ([newURLScheme caseInsensitiveCompare: @"http"] !=
		    OFOrderedSame &&
		    [newURLScheme caseInsensitiveCompare: @"https"] !=
		    OFOrderedSame)
			follow = false;

		if (!_client->_allowsInsecureRedirects &&
		    [URL.scheme caseInsensitiveCompare: @"https"] ==
		    OFOrderedSame &&
		    [newURLScheme caseInsensitiveCompare: @"http"] ==
		    OFOrderedSame)
			follow = false;

		if (follow && [_client->_delegate respondsToSelector: @selector(
		    client:shouldFollowRedirect:statusCode:request:response:)])
			follow = [_client->_delegate client: _client
				       shouldFollowRedirect: newURL
						 statusCode: _status
						    request: _request
						   response: response];
		else if (follow)
			follow = defaultShouldFollow(_request.method, _status);

		if (follow) {
			OFDictionary OF_GENERIC(OFString *, OFString *)
			    *headers = _request.headers;
			OFHTTPRequest *newRequest =
			    [[_request copy] autorelease];
			OFMutableDictionary *newHeaders =
			    [[headers mutableCopy] autorelease];

			if (![newURL.host isEqual: URL.host])
				[newHeaders removeObjectForKey: @"Host"];

			/*
			 * 303 means the request should be converted to a GET
			 * request before redirection. This also means stripping
			 * the entity of the request.
			 */
			if (_status == 303) {
				OFEnumerator *keyEnumerator, *objectEnumerator;
				OFString *key, *object;

				keyEnumerator = [headers keyEnumerator];
				objectEnumerator = [headers objectEnumerator];
				while ((key = [keyEnumerator nextObject]) !=
				    nil &&
				    (object = [objectEnumerator nextObject]) !=
				    nil)
					if ([key hasPrefix: @"Content-"] ||
					    [key hasPrefix: @"Transfer-"])
						[newHeaders
						    removeObjectForKey: key];

				newRequest.method = OFHTTPRequestMethodGet;
			}

			newRequest.URL = newURL;
			newRequest.headers = newHeaders;

			_client->_inProgress = false;

			[_client asyncPerformRequest: newRequest
					   redirects: _redirects - 1];
			return;
		}
	}

	_client->_inProgress = false;

	if (_status / 100 != 2)
		exception = [OFHTTPRequestFailedException
		    exceptionWithRequest: _request
				response: response];
	else
		exception = nil;

	[_client->_delegate performSelector: @selector(client:didPerformRequest:
						 response:exception:)
				 withObject: _client
				 withObject: _request
				 withObject: response
				 withObject: exception
				 afterDelay: 0];
}

- (void)createResponseWithStream: (OFStream *)stream
{
	@try {
		[self createResponseWithStreamOrThrow: stream];
	} @catch (id e) {
		[self raiseException: e];
	}
}

- (bool)handleFirstLine: (OFString *)line
{
	long long status;

	/*
	 * It's possible that the write succeeds on a connection that is
	 * keep-alive, but the connection has already been closed by the remote
	 * end due to a timeout. In this case, we need to reconnect.
	 */
	if (line == nil) {
		[self closeAndReconnect];
		return false;
	}

	if (![line hasPrefix: @"HTTP/"] || line.length < 9 ||
	    [line characterAtIndex: 8] != ' ')
		@throw [OFInvalidServerReplyException exception];

	_version = [[line substringWithRange: OFRangeMake(5, 3)] copy];
	if (![_version isEqual: @"1.0"] && ![_version isEqual: @"1.1"])
		@throw [OFUnsupportedVersionException
		    exceptionWithVersion: _version];

	status = [line substringWithRange: OFRangeMake(9, 3)].longLongValue;

	if (status < 0 || status > 599)
		@throw [OFInvalidServerReplyException exception];

	_status = (short)status;

	return true;
}

- (bool)handleServerHeader: (OFString *)line stream: (OFStream *)stream
{
	OFString *key, *value, *old;
	const char *lineC, *tmp;
	char *keyC;

	if (line == nil)
		@throw [OFInvalidServerReplyException exception];

	if (line.length == 0) {
		[_serverHeaders makeImmutable];

		if ([_client->_delegate respondsToSelector: @selector(client:
		    didReceiveHeaders:statusCode:request:)])
			[_client->_delegate client: _client
				 didReceiveHeaders: _serverHeaders
					statusCode: _status
					   request: _request];

		stream.delegate = nil;

		[self performSelector: @selector(createResponseWithStream:)
			   withObject: stream
			   afterDelay: 0];

		return false;
	}

	lineC = line.UTF8String;

	if ((tmp = strchr(lineC, ':')) == NULL)
		@throw [OFInvalidServerReplyException exception];

	keyC = OFAllocMemory(tmp - lineC + 1, 1);
	memcpy(keyC, lineC, tmp - lineC);
	keyC[tmp - lineC] = '\0';
	normalizeKey(keyC);

	@try {
		key = [OFString stringWithUTF8StringNoCopy: keyC
					      freeWhenDone: true];
	} @catch (id e) {
		OFFreeMemory(keyC);
		@throw e;
	}

	do {
		tmp++;
	} while (*tmp == ' ');

	value = [OFString stringWithUTF8String: tmp];

	old = [_serverHeaders objectForKey: key];
	if (old != nil)
		value = [old stringByAppendingFormat: @",%@", value];

	[_serverHeaders setObject: value forKey: key];

	return true;
}

- (bool)stream: (OFStream *)stream
   didReadLine: (OFString *)line
     exception: (id)exception
{
	bool ret;

	if (exception != nil) {
		if ([exception isKindOfClass:
		    [OFInvalidEncodingException class]])
			exception = [OFInvalidServerReplyException exception];

		[self raiseException: exception];
		return false;
	}

	@try {
		if (_firstLine) {
			_firstLine = false;
			ret = [self handleFirstLine: line];
		} else
			ret = [self handleServerHeader: line stream: stream];
	} @catch (id e) {
		[self raiseException: e];
		ret = false;
	}

	return ret;
}

- (OFString *)stream: (OFStream *)stream
      didWriteString: (OFString *)string
	    encoding: (OFStringEncoding)encoding
	bytesWritten: (size_t)bytesWritten
	   exception: (id)exception
{
	OFDictionary OF_GENERIC(OFString *, OFString *) *headers;
	bool chunked;

	if (exception != nil) {
		if ([exception isKindOfClass: [OFWriteFailedException class]] &&
		    ([exception errNo] == ECONNRESET ||
		    [exception errNo] == EPIPE)) {
			/* In case a keep-alive connection timed out */
			[self closeAndReconnect];
			return nil;
		}

		[self raiseException: exception];
		return nil;
	}

	_firstLine = true;

	headers = _request.headers;
	chunked = [[headers objectForKey: @"Transfer-Encoding"]
	    isEqual: @"chunked"];

	if (chunked || [headers objectForKey: @"Content-Length"] != nil) {
		stream.delegate = nil;

		OFStream *requestBody = [[[OFHTTPClientRequestBodyStream alloc]
		    initWithHandler: self stream: stream] autorelease];

		if ([_client->_delegate respondsToSelector:
		    @selector(client:wantsRequestBody:request:)])
			[_client->_delegate client: _client
				  wantsRequestBody: requestBody
					   request: _request];
	} else
		[stream asyncReadLine];

	return nil;
}

- (void)handleStream: (OFStream *)stream
{
	/*
	 * As a work around for a bug with split packets in lighttpd when using
	 * HTTPS, we construct the complete request in a buffer string and then
	 * send it all at once.
	 *
	 * We do not use the streams's write buffer in case we need to resend
	 * the entire request (e.g. in case a keep-alive connection timed out).
	 */

	@try {
		[stream asyncWriteString: constructRequestString(_request)];
	} @catch (id e) {
		[self raiseException: e];
		return;
	}
}

-     (void)socket: (OFTCPSocket *)sock
  didConnectToHost: (OFString *)host
	      port: (uint16_t)port
	 exception: (id)exception
{
	if (exception != nil) {
		[self raiseException: exception];
		return;
	}

	if ([_client->_delegate respondsToSelector:
	    @selector(client:didCreateTCPSocket:request:)])
		[_client->_delegate client: _client
			didCreateTCPSocket: sock
				   request: _request];

	if ([_request.URL.scheme caseInsensitiveCompare: @"https"] ==
	    OFOrderedSame) {
		OFTLSStream *stream;
		@try {
			stream = [OFTLSStream streamWithStream: sock];
		} @catch (OFNotImplementedException *e) {
			[self raiseException:
			    [OFUnsupportedProtocolException
			    exceptionWithURL: _request.URL]];
			return;
		}

		if ([_client->_delegate respondsToSelector:
		    @selector(client:didCreateTLSStream:request:)])
			[_client->_delegate client: _client
				didCreateTLSStream: stream
					   request: _request];

		stream.delegate = self;
		[stream asyncPerformClientHandshakeWithHost: _request.URL.host];
	} else {
		sock.delegate = self;
		[self performSelector: @selector(handleStream:)
			   withObject: sock
			   afterDelay: 0];
	}
}

-		       (void)stream: (OFTLSStream *)stream
  didPerformClientHandshakeWithHost: (OFString *)host
			  exception: (id)exception
{
	if (exception != nil) {
		[self raiseException: exception];
		return;
	}

	[self performSelector: @selector(handleStream:)
		   withObject: stream
		   afterDelay: 0];
}

- (void)start
{
	OFURL *URL = _request.URL;
	OFStream *stream;

	/* Can we reuse the last socket? */
	if (_client->_stream != nil && !_client->_stream.atEndOfStream &&
	    [_client->_lastURL.scheme isEqual: URL.scheme] &&
	    [_client->_lastURL.host isEqual: URL.host] &&
	    (_client->_lastURL.port == URL.port ||
	    [_client->_lastURL.port isEqual: URL.port]) &&
	    (_client->_lastWasHEAD || _client->_lastResponse.atEndOfStream)) {
		/*
		 * Set _stream to nil, so that in case of an error it won't be
		 * reused. If everything is successful, we set _stream again
		 * at the end.
		 */
		stream = [_client->_stream autorelease];
		_client->_stream = nil;

		[_client->_lastURL release];
		_client->_lastURL = nil;

		[_client->_lastResponse release];
		_client->_lastResponse = nil;

		stream.delegate = self;

		[self performSelector: @selector(handleStream:)
			   withObject: stream
			   afterDelay: 0];
	} else
		[self closeAndReconnect];
}

- (void)closeAndReconnect
{
	@try {
		OFURL *URL = _request.URL;
		OFTCPSocket *sock;
		uint16_t port;
		OFNumber *URLPort;

		[_client close];

		sock = [OFTCPSocket socket];

		if ([URL.scheme caseInsensitiveCompare: @"https"] ==
		    OFOrderedSame)
			port = 443;
		else
			port = 80;

		URLPort = URL.port;
		if (URLPort != nil)
			port = URLPort.unsignedShortValue;

		sock.delegate = self;
		[sock asyncConnectToHost: URL.host port: port];
	} @catch (id e) {
		[self raiseException: e];
	}
}
@end

@implementation OFHTTPClientRequestBodyStream
- (instancetype)initWithHandler: (OFHTTPClientRequestHandler *)handler
			 stream: (OFStream *)stream
{
	self = [super init];

	@try {
		OFDictionary OF_GENERIC(OFString *, OFString *) *headers;
		OFString *transferEncoding, *contentLengthString;

		_handler = [handler retain];
		_stream = [stream retain];

		headers = _handler->_request.headers;

		transferEncoding = [headers objectForKey: @"Transfer-Encoding"];
		_chunked = [transferEncoding isEqual: @"chunked"];

		contentLengthString = [headers objectForKey: @"Content-Length"];
		if (contentLengthString != nil) {
			if (_chunked || contentLengthString.length == 0)
				@throw [OFInvalidArgumentException
				    exception];

			_toWrite = contentLengthString.unsignedLongLongValue;
		} else if (!_chunked)
			@throw [OFInvalidArgumentException exception];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	if (_stream != nil)
		[self close];

	[_handler release];

	[super dealloc];
}

- (size_t)lowlevelWriteBuffer: (const void *)buffer length: (size_t)length
{
	/* TODO: Use non-blocking writes */

	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	/*
	 * We must not send a chunk of size 0, as that would end the body. We
	 * always ignore writing 0 bytes to still allow writing 0 bytes after
	 * the end of stream.
	 */
	if (length == 0)
		return 0;

	if (_atEndOfStream)
		@throw [OFWriteFailedException exceptionWithObject: self
						   requestedLength: length
						      bytesWritten: 0
							     errNo: ENOTCONN];

	if (_chunked)
		[_stream writeFormat: @"%zX\r\n", length];
	else if (length > _toWrite)
		@throw [OFOutOfRangeException exception];

	[_stream writeBuffer: buffer length: length];
	if (_chunked)
		[_stream writeString: @"\r\n"];

	if (!_chunked) {
		_toWrite -= length;

		if (_toWrite == 0)
			_atEndOfStream = true;
	}

	return length;
}

- (bool)lowlevelIsAtEndOfStream
{
	return _atEndOfStream;
}

- (void)close
{
	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	if (_chunked)
		[_stream writeString: @"0\r\n\r\n"];
	else if (_toWrite > 0)
		@throw [OFTruncatedDataException exception];

	_stream.delegate = _handler;
	[_stream asyncReadLine];

	[_stream release];
	_stream = nil;

	[super close];
}

- (int)fileDescriptorForWriting
{
	return ((OFStream <OFReadyForWritingObserving> *)_stream)
	    .fileDescriptorForWriting;
}
@end

@implementation OFHTTPClientResponse
@synthesize of_keepAlive = _keepAlive;

- (instancetype)initWithStream: (OFStream *)stream
{
	self = [super init];

	_stream = [stream retain];

	return self;
}

- (void)dealloc
{
	if (_stream != nil)
		[self close];

	[super dealloc];
}

- (void)setHeaders: (OFDictionary *)headers
{
	OFString *contentLength;

	super.headers = headers;

	_chunked = [[headers objectForKey: @"Transfer-Encoding"]
	    isEqual: @"chunked"];

	contentLength = [headers objectForKey: @"Content-Length"];
	if (contentLength != nil) {
		if (_chunked || contentLength.length == 0)
			@throw [OFInvalidServerReplyException exception];

		_hasContentLength = true;

		@try {
			unsigned long long toRead =
			    contentLength.unsignedLongLongValue;

			if (toRead > LLONG_MAX)
				@throw [OFOutOfRangeException exception];

			_toRead = (long long)toRead;
		} @catch (OFInvalidFormatException *e) {
			@throw [OFInvalidServerReplyException exception];
		}
	}
}

- (size_t)lowlevelReadIntoBuffer: (void *)buffer length: (size_t)length
{
	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	if (_atEndOfStream)
		return 0;

	if (!_hasContentLength && !_chunked)
		return [_stream readIntoBuffer: buffer length: length];

	if (_stream.atEndOfStream)
		@throw [OFTruncatedDataException exception];

	/* Content-Length */
	if (!_chunked) {
		size_t ret;

		if (length > (unsigned long long)_toRead)
			length = (size_t)_toRead;

		ret = [_stream readIntoBuffer: buffer length: length];
		if (ret > length)
			@throw [OFOutOfRangeException exception];

		_toRead -= ret;

		if (_toRead == 0)
			_atEndOfStream = true;

		return ret;
	}

	/* Chunked */
	if (_toRead == -2) {
		char tmp[2];

		switch ([_stream readIntoBuffer: tmp length: 2]) {
		case 2:
			_toRead++;
			if (tmp[1] != '\n')
				@throw [OFInvalidServerReplyException
				    exception];
		case 1:
			_toRead++;
			if (tmp[0] != '\r')
				@throw [OFInvalidServerReplyException
				    exception];
		}

		if (_setAtEndOfStream && _toRead == 0)
			_atEndOfStream = true;

		return 0;
	} else if (_toRead == -1) {
		char tmp;

		if ([_stream readIntoBuffer: &tmp length: 1] == 1) {
			_toRead++;
			if (tmp != '\n')
				@throw [OFInvalidServerReplyException
				    exception];
		}

		if (_setAtEndOfStream && _toRead == 0)
			_atEndOfStream = true;

		return 0;
	} else if (_toRead > 0) {
		if (length > (unsigned long long)_toRead)
			length = (size_t)_toRead;

		length = [_stream readIntoBuffer: buffer length: length];

		_toRead -= length;
		if (_toRead == 0)
			_toRead = -2;

		return length;
	} else {
		void *pool = objc_autoreleasePoolPush();
		OFString *line;
		size_t pos;

		@try {
			line = [_stream tryReadLine];
		} @catch (OFInvalidEncodingException *e) {
			@throw [OFInvalidServerReplyException exception];
		}

		if (line == nil)
			return 0;

		pos = [line rangeOfString: @";"].location;
		if (pos != OFNotFound)
			line = [line substringToIndex: pos];

		if (line.length < 1) {
			/*
			 * We have read the empty string because the stream is
			 * at end of stream.
			 */
			if (_stream.atEndOfStream && pos == OFNotFound)
				@throw [OFTruncatedDataException exception];
			else
				@throw [OFInvalidServerReplyException
				    exception];
		}

		@try {
			unsigned long long toRead =
			    [line unsignedLongLongValueWithBase: 16];

			if (toRead > LLONG_MAX)
				@throw [OFOutOfRangeException exception];

			_toRead = (long long)toRead;
		} @catch (OFInvalidFormatException *e) {
			@throw [OFInvalidServerReplyException exception];
		}

		if (_toRead == 0) {
			_setAtEndOfStream = true;
			_toRead = -2;
		}

		objc_autoreleasePoolPop(pool);

		return 0;
	}
}

- (bool)lowlevelIsAtEndOfStream
{
	if (_atEndOfStream)
		return true;

	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	if (!_hasContentLength && !_chunked)
		return _stream.atEndOfStream;

	return _atEndOfStream;
}

- (int)fileDescriptorForReading
{
	if (_stream == nil)
		return -1;

	return ((OFStream <OFReadyForReadingObserving> *)_stream)
	    .fileDescriptorForReading;
}

- (bool)hasDataInReadBuffer
{
	return (super.hasDataInReadBuffer || _stream.hasDataInReadBuffer);
}

- (void)close
{
	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	_atEndOfStream = false;

	[_stream release];
	_stream = nil;

	[super close];
}
@end

@implementation OFHTTPClientSyncPerformer
- (instancetype)initWithClient: (OFHTTPClient *)client
{
	self = [super init];

	@try {
		_client = [client retain];
		_delegate = client.delegate;

		_client.delegate = self;
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	_client.delegate = _delegate;
	[_client release];

	[super dealloc];
}

- (OFHTTPResponse *)performRequest: (OFHTTPRequest *)request
			 redirects: (unsigned int)redirects
{
	[_client asyncPerformRequest: request redirects: redirects];
	[[OFRunLoop currentRunLoop] run];
	return _response;
}

-      (void)client: (OFHTTPClient *)client
  didPerformRequest: (OFHTTPRequest *)request
	   response: (OFHTTPResponse *)response
	  exception: (id)exception
{
	if (exception != nil) {
		/*
		 * Restore the delegate - we're giving up, but not reaching the
		 * release of the autorelease pool that contains us, so
		 * resetting it via -[dealloc] might be too late.
		 */
		_client.delegate = _delegate;

		@throw exception;
	}

	[[OFRunLoop currentRunLoop] stop];

	[_response release];
	_response = [response retain];

	[_delegate     client: client
	    didPerformRequest: request
		     response: response
		    exception: nil];
}

-	(void)client: (OFHTTPClient *)client
  didCreateTCPSocket: (OFTCPSocket *)TCPSocket
	     request: (OFHTTPRequest *)request
{
	if ([_delegate respondsToSelector:
	    @selector(client:didCreateTCPSocket:request:)])
		[_delegate	client: client
		    didCreateTCPSocket: TCPSocket
			       request: request];
}

-	(void)client: (OFHTTPClient *)client
  didCreateTLSStream: (OFTLSStream *)TLSStream
	     request: (OFHTTPRequest *)request
{
	if ([_delegate respondsToSelector:
	    @selector(client:didCreateTLSStream:request:)])
		[_delegate	client: client
		    didCreateTLSStream: TLSStream
			       request: request];
}

-     (void)client: (OFHTTPClient *)client
  wantsRequestBody: (OFStream *)body
	   request: (OFHTTPRequest *)request
{
	if ([_delegate respondsToSelector:
	    @selector(client:wantsRequestBody:request:)])
		[_delegate    client: client
		    wantsRequestBody: body
			     request: request];
}

-      (void)client: (OFHTTPClient *)client
  didReceiveHeaders: (OFDictionary OF_GENERIC(OFString *, OFString *) *)headers
	 statusCode: (short)statusCode
	    request: (OFHTTPRequest *)request
{
	if ([_delegate respondsToSelector:
	    @selector(client:didReceiveHeaders:statusCode:request:)])
		[_delegate     client: client
		    didReceiveHeaders: headers
			   statusCode: statusCode
			      request: request];
}

-	  (bool)client: (OFHTTPClient *)client
  shouldFollowRedirect: (OFURL *)URL
	    statusCode: (short)statusCode
	       request: (OFHTTPRequest *)request
	      response: (OFHTTPResponse *)response
{
	if ([_delegate respondsToSelector: @selector(client:
	    shouldFollowRedirect:statusCode:request:response:)])
		return [_delegate client: client
		    shouldFollowRedirect: URL
			      statusCode: statusCode
				 request: request
				response: response];
	else
		return defaultShouldFollow(request.method, statusCode);
}
@end

@implementation OFHTTPClient
@synthesize delegate = _delegate;
@synthesize allowsInsecureRedirects = _allowsInsecureRedirects;

+ (instancetype)client
{
	return [[[self alloc] init] autorelease];
}

- (void)dealloc
{
	[self close];

	[super dealloc];
}

- (OFHTTPResponse *)performRequest: (OFHTTPRequest *)request
{
	return [self performRequest: request redirects: defaultRedirects];
}

- (OFHTTPResponse *)performRequest: (OFHTTPRequest *)request
			 redirects: (unsigned int)redirects
{
	void *pool = objc_autoreleasePoolPush();
	OFHTTPClientSyncPerformer *syncPerformer =
	    [[[OFHTTPClientSyncPerformer alloc] initWithClient: self]
	    autorelease];
	OFHTTPResponse *response = [syncPerformer performRequest: request
						       redirects: redirects];

	[response retain];

	objc_autoreleasePoolPop(pool);

	return [response autorelease];
}

- (void)asyncPerformRequest: (OFHTTPRequest *)request
{
	[self asyncPerformRequest: request redirects: defaultRedirects];
}

- (void)asyncPerformRequest: (OFHTTPRequest *)request
		  redirects: (unsigned int)redirects
{
	void *pool = objc_autoreleasePoolPush();
	OFURL *URL = request.URL;
	OFString *scheme = URL.scheme;

	if ([scheme caseInsensitiveCompare: @"http"] != OFOrderedSame &&
	    [scheme caseInsensitiveCompare: @"https"] != OFOrderedSame)
		@throw [OFUnsupportedProtocolException exceptionWithURL: URL];

	if (_inProgress)
		/* TODO: Find a better exception */
		@throw [OFAlreadyConnectedException exception];

	_inProgress = true;

	[[[[OFHTTPClientRequestHandler alloc]
	    initWithClient: self
		   request: request
		 redirects: redirects] autorelease] start];

	objc_autoreleasePoolPop(pool);
}

- (void)close
{
	[_stream release];
	_stream = nil;

	[_lastURL release];
	_lastURL = nil;

	[_lastResponse release];
	_lastResponse = nil;
}
@end