ObjFW  Artifact [9d3b80f535]

Artifact 9d3b80f53585429093a0cad9a8809ab517962795c8eafdbecc84c0f934545b46:

• File src/OFHTTPServer.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: 19818) [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.
 */

#include "config.h"

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

#import "OFHTTPServer.h"
#import "OFArray.h"
#import "OFData.h"
#import "OFDate.h"
#import "OFDictionary.h"
#import "OFHTTPRequest.h"
#import "OFHTTPResponse.h"
#import "OFNumber.h"
#import "OFSocket+Private.h"
#import "OFTCPSocket.h"
#import "OFThread.h"
#import "OFTimer.h"
#import "OFURL.h"

#import "OFAlreadyConnectedException.h"
#import "OFInvalidArgumentException.h"
#import "OFInvalidEncodingException.h"
#import "OFInvalidFormatException.h"
#import "OFNotOpenException.h"
#import "OFOutOfMemoryException.h"
#import "OFOutOfRangeException.h"
#import "OFTruncatedDataException.h"
#import "OFUnsupportedProtocolException.h"
#import "OFWriteFailedException.h"

/*
 * FIXME: Key normalization replaces headers like "DNT" with "Dnt".
 * FIXME: Errors are not reported to the user.
 */

@interface OFHTTPServer () <OFTCPSocketDelegate>
@end

OF_DIRECT_MEMBERS
@interface OFHTTPServerResponse: OFHTTPResponse <OFReadyForWritingObserving>
{
	OFStreamSocket *_socket;
	OFHTTPServer *_server;
	OFHTTPRequest *_request;
	bool _chunked, _headersSent;
}

- (instancetype)initWithSocket: (OFStreamSocket *)sock
			server: (OFHTTPServer *)server
		       request: (OFHTTPRequest *)request;
@end

OF_DIRECT_MEMBERS
@interface OFHTTPServerConnection: OFObject <OFTCPSocketDelegate>
{
@public
	OFStreamSocket *_socket;
	OFHTTPServer *_server;
	OFTimer *_timer;
	enum {
		stateAwaitingProlog,
		stateParsingHeaders,
		stateSendResponse
	} _state;
	uint8_t _HTTPMinorVersion;
	OFHTTPRequestMethod _method;
	OFString *_host, *_path;
	uint16_t _port;
	OFMutableDictionary *_headers;
	size_t _contentLength;
	OFStream *_requestBody;
}

- (instancetype)initWithSocket: (OFStreamSocket *)sock
			server: (OFHTTPServer *)server;
- (bool)parseProlog: (OFString *)line;
- (bool)parseHeaders: (OFString *)line;
- (bool)sendErrorAndClose: (short)statusCode;
- (void)createResponse;
@end

OF_DIRECT_MEMBERS
@interface OFHTTPServerRequestBodyStream: OFStream <OFReadyForReadingObserving>
{
	OFStreamSocket *_socket;
	bool _chunked;
	long long _toRead;
	bool _atEndOfStream, _setAtEndOfStream;
}

- (instancetype)initWithSocket: (OFStreamSocket *)sock
		       chunked: (bool)chunked
		 contentLength: (unsigned long long)contentLength;
@end

#ifdef OF_HAVE_THREADS
OF_DIRECT_MEMBERS
@interface OFHTTPServerThread: OFThread
- (void)stop;
@end
#endif

static OFString *
normalizedKey(OFString *key)
{
	char *cString = OFStrDup(key.UTF8String);
	unsigned char *tmp = (unsigned char *)cString;
	bool firstLetter = true;
	OFString *ret;

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

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

		firstLetter = false;
		tmp++;
	}

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

	return ret;
}

@implementation OFHTTPServerResponse
- (instancetype)initWithSocket: (OFStreamSocket *)sock
			server: (OFHTTPServer *)server
		       request: (OFHTTPRequest *)request
{
	self = [super init];

	_statusCode = 500;
	_socket = [sock retain];
	_server = [server retain];
	_request = [request retain];

	return self;
}

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

	[_server release];
	[_request release];

	[super dealloc];
}

- (void)of_sendHeaders
{
	void *pool = objc_autoreleasePoolPush();
	OFMutableDictionary OF_GENERIC(OFString *, OFString *) *headers;
	OFEnumerator *keyEnumerator, *valueEnumerator;
	OFString *key, *value;

	[_socket writeFormat: @"HTTP/%@ %hd %@\r\n",
			      self.protocolVersionString, _statusCode,
			      OFHTTPStatusCodeString(_statusCode)];

	headers = [[_headers mutableCopy] autorelease];

	if ([headers objectForKey: @"Date"] == nil) {
		OFString *date = [[OFDate date]
		    dateStringWithFormat: @"%a, %d %b %Y %H:%M:%S GMT"];
		[headers setObject: date forKey: @"Date"];
	}

	if ([headers objectForKey: @"Server"] == nil) {
		OFString *name = _server.name;

		if (name != nil)
			[headers setObject: name forKey: @"Server"];
	}

	keyEnumerator = [headers keyEnumerator];
	valueEnumerator = [headers objectEnumerator];
	while ((key = [keyEnumerator nextObject]) != nil &&
	    (value = [valueEnumerator nextObject]) != nil)
		[_socket writeFormat: @"%@: %@\r\n", key, value];

	[_socket writeString: @"\r\n"];

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

	objc_autoreleasePoolPop(pool);
}

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

	void *pool;

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

	if (!_headersSent)
		[self of_sendHeaders];

	if (!_chunked) {
		@try {
			[_socket writeBuffer: buffer length: length];
		} @catch (OFWriteFailedException *e) {
			if (e.errNo == EWOULDBLOCK)
				return e.bytesWritten;

			@throw e;
		}

		return length;
	}

	pool = objc_autoreleasePoolPush();
	[_socket writeString: [OFString stringWithFormat: @"%zX\r\n", length]];
	objc_autoreleasePoolPop(pool);

	[_socket writeBuffer: buffer length: length];
	[_socket writeString: @"\r\n"];

	return length;
}

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

	@try {
		if (!_headersSent)
			[self of_sendHeaders];

		if (_chunked)
			[_socket writeString: @"0\r\n\r\n"];
	} @catch (OFWriteFailedException *e) {
		id <OFHTTPServerDelegate> delegate = _server.delegate;

		if ([delegate respondsToSelector: @selector(server:
		  didReceiveExceptionForResponse:request:exception:)])
			[delegate		    server: _server
			    didReceiveExceptionForResponse: self
						   request: _request
						 exception: e];
	}

	[_socket release];
	_socket = nil;

	[super close];
}

- (int)fileDescriptorForWriting
{
	if (_socket == nil)
		return -1;

	return _socket.fileDescriptorForWriting;
}
@end

@implementation OFHTTPServerConnection
- (instancetype)initWithSocket: (OFStreamSocket *)sock
			server: (OFHTTPServer *)server
{
	self = [super init];

	@try {
		_socket = [sock retain];
		_server = [server retain];
		_timer = [[OFTimer
		    scheduledTimerWithTimeInterval: 10
					    target: _socket
					  selector: @selector(
							cancelAsyncRequests)
					   repeats: false] retain];
		_state = stateAwaitingProlog;
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[_socket release];
	[_server release];

	[_timer invalidate];
	[_timer release];

	[_host release];
	[_path release];
	[_headers release];
	[_requestBody release];

	[super dealloc];
}

- (bool)stream: (OFStream *)sock
   didReadLine: (OFString *)line
     exception: (id)exception
{
	if (line == nil || exception != nil)
		return false;

	@try {
		switch (_state) {
		case stateAwaitingProlog:
			return [self parseProlog: line];
		case stateParsingHeaders:
			return [self parseHeaders: line];
		default:
			return false;
		}
	} @catch (OFWriteFailedException *e) {
		return false;
	}

	OFEnsure(0);
}

- (bool)parseProlog: (OFString *)line
{
	OFString *method;
	OFMutableString *path;
	size_t pos;

	@try {
		OFString *version = [line
		    substringWithRange: OFRangeMake(line.length - 9, 9)];
		OFUnichar tmp;

		if (![version hasPrefix: @" HTTP/1."])
			return [self sendErrorAndClose: 505];

		tmp = [version characterAtIndex: 8];
		if (tmp < '0' || tmp > '9')
			return [self sendErrorAndClose: 400];

		_HTTPMinorVersion = (uint8_t)(tmp - '0');
	} @catch (OFOutOfRangeException *e) {
		return [self sendErrorAndClose: 400];
	}

	pos = [line rangeOfString: @" "].location;
	if (pos == OFNotFound)
		return [self sendErrorAndClose: 400];

	method = [line substringToIndex: pos];
	@try {
		_method = OFHTTPRequestMethodParseName(method);
	} @catch (OFInvalidArgumentException *e) {
		return [self sendErrorAndClose: 405];
	}

	@try {
		OFRange range = OFRangeMake(pos + 1, line.length - pos - 10);

		path = [[[line substringWithRange:
		    range] mutableCopy] autorelease];
	} @catch (OFOutOfRangeException *e) {
		return [self sendErrorAndClose: 400];
	}

	[path deleteEnclosingWhitespaces];
	[path makeImmutable];

	if (![path hasPrefix: @"/"])
		return [self sendErrorAndClose: 400];

	_headers = [[OFMutableDictionary alloc] init];
	_path = [path copy];
	_state = stateParsingHeaders;

	return true;
}

- (bool)parseHeaders: (OFString *)line
{
	OFString *key, *value, *old;
	size_t pos;

	if (line.length == 0) {
		bool chunked = [[_headers objectForKey: @"Transfer-Encoding"]
		    isEqual: @"chunked"];
		OFString *contentLengthString =
		    [_headers objectForKey: @"Content-Length"];
		unsigned long long contentLength = 0;

		if (contentLengthString != nil) {
			if (chunked || contentLengthString.length == 0)
				return [self sendErrorAndClose: 400];

			@try {
				contentLength =
				    contentLengthString.unsignedLongLongValue;
			} @catch (OFInvalidFormatException *e) {
				return [self sendErrorAndClose: 400];
			}
		}

		if (chunked || contentLengthString != nil) {
			[_requestBody release];
			_requestBody = nil;
			_requestBody = [[OFHTTPServerRequestBodyStream alloc]
			    initWithSocket: _socket
				   chunked: chunked
			     contentLength: contentLength];

			[_timer invalidate];
			[_timer release];
			_timer = nil;
		}

		_state = stateSendResponse;
		[self createResponse];

		return false;
	}

	pos = [line rangeOfString: @":"].location;
	if (pos == OFNotFound)
		return [self sendErrorAndClose: 400];

	key = [line substringToIndex: pos];
	value = [line substringFromIndex: pos + 1];

	key = normalizedKey(key.stringByDeletingTrailingWhitespaces);
	value = value.stringByDeletingLeadingWhitespaces;

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

	[_headers setObject: value forKey: key];

	if ([key isEqual: @"Host"]) {
		pos = [value rangeOfString: @":"
				   options: OFStringSearchBackwards].location;

		if (pos != OFNotFound) {
			[_host release];
			_host = [[value substringToIndex: pos] retain];

			@try {
				unsigned long long portTmp =
				    [value substringFromIndex: pos + 1]
				    .unsignedLongLongValue;

				if (portTmp < 1 || portTmp > UINT16_MAX)
					return [self sendErrorAndClose: 400];

				_port = (uint16_t)portTmp;
			} @catch (OFInvalidFormatException *e) {
				return [self sendErrorAndClose: 400];
			}
		} else {
			[_host release];
			_host = [value retain];
			_port = 80;
		}
	}

	return true;
}

- (bool)sendErrorAndClose: (short)statusCode
{
	OFString *date = [[OFDate date]
	    dateStringWithFormat: @"%a, %d %b %Y %H:%M:%S GMT"];
	[_socket writeFormat: @"HTTP/1.1 %hd %@\r\n"
			      @"Date: %@\r\n"
			      @"Server: %@\r\n"
			      @"\r\n",
			      statusCode, OFHTTPStatusCodeString(statusCode),
			      date, _server.name];
	return false;
}

- (void)createResponse
{
	void *pool = objc_autoreleasePoolPush();
	OFMutableURL *URL;
	OFHTTPRequest *request;
	OFHTTPServerResponse *response;
	size_t pos;

	[_timer invalidate];
	[_timer release];
	_timer = nil;

	if (_host == nil || _port == 0) {
		if (_HTTPMinorVersion > 0) {
			[self sendErrorAndClose: 400];
			return;
		}

		[_host release];
		_host = [_server.host copy];
		_port = [_server port];
	}

	URL = [OFMutableURL URL];
	URL.scheme = @"http";
	URL.host = _host;
	if (_port != 80)
		URL.port = [OFNumber numberWithUnsignedShort: _port];

	if ((pos = [_path rangeOfString: @"?"].location) != OFNotFound) {
		OFString *path, *query;

		path = [_path substringToIndex: pos];
		query = [_path substringFromIndex: pos + 1];

		URL.URLEncodedPath = path;
		URL.URLEncodedQuery = query;
	} else
		URL.URLEncodedPath = _path;

	[URL makeImmutable];

	request = [OFHTTPRequest requestWithURL: URL];
	request.method = _method;
	request.protocolVersion =
	    (OFHTTPRequestProtocolVersion){ 1, _HTTPMinorVersion };
	request.headers = _headers;
	request.remoteAddress = _socket.remoteAddress;

	response = [[[OFHTTPServerResponse alloc]
	    initWithSocket: _socket
		    server: _server
		   request: request] autorelease];

	[_server.delegate server: _server
	       didReceiveRequest: request
		     requestBody: _requestBody
			response: response];

	objc_autoreleasePoolPop(pool);
}
@end

@implementation OFHTTPServerRequestBodyStream
- (instancetype)initWithSocket: (OFStreamSocket *)sock
		       chunked: (bool)chunked
		 contentLength: (unsigned long long)contentLength
{
	self = [super init];

	@try {
		if (contentLength > LLONG_MAX)
			@throw [OFOutOfRangeException exception];

		_socket = [sock retain];
		_chunked = chunked;
		_toRead = (long long)contentLength;

		if (_chunked && _toRead > 0)
			@throw [OFInvalidArgumentException exception];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

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

	[super dealloc];
}

- (bool)lowlevelIsAtEndOfStream
{
	return _atEndOfStream;
}

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

	if (_atEndOfStream)
		return 0;

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

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

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

		ret = [_socket readIntoBuffer: buffer length: length];

		_toRead -= ret;

		if (_toRead == 0)
			_atEndOfStream = true;

		return ret;
	}

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

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

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

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

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

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

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

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

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

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

		@try {
			line = [_socket tryReadLine];
		} @catch (OFInvalidEncodingException *e) {
			@throw [OFInvalidFormatException 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 socket is
			 * at end of stream.
			 */
			if (_socket.atEndOfStream && pos == OFNotFound)
				@throw [OFTruncatedDataException exception];
			else
				@throw [OFInvalidFormatException exception];
		}

		toRead = [line unsignedLongLongValueWithBase: 16];
		if (toRead > LLONG_MAX)
			@throw [OFOutOfRangeException exception];
		_toRead = (long long)toRead;

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

		objc_autoreleasePoolPop(pool);

		return 0;
	}
}

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

- (int)fileDescriptorForReading
{
	return _socket.fileDescriptorForReading;
}

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

	[_socket release];
	_socket = nil;

	[super close];
}
@end

#ifdef OF_HAVE_THREADS
@implementation OFHTTPServerThread
- (void)stop
{
	[[OFRunLoop currentRunLoop] stop];
	[self join];
}
@end
#endif

@implementation OFHTTPServer
@synthesize delegate = _delegate, name = _name;

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

- (instancetype)init
{
	self = [super init];

	_name = @"OFHTTPServer (ObjFW's HTTP server class "
	    @"<https://objfw.nil.im/>)";
#ifdef OF_HAVE_THREADS
	_numberOfThreads = 1;
#endif

	return self;
}

- (void)dealloc
{
	[self stop];

	[_host release];
	[_listeningSocket release];
	[_name release];

	[super dealloc];
}

- (void)setHost: (OFString *)host
{
	OFString *old;

	if (_listeningSocket != nil)
		@throw [OFAlreadyConnectedException exception];

	old = _host;
	_host = [host copy];
	[old release];
}

- (OFString *)host
{
	return _host;
}

- (void)setPort: (uint16_t)port
{
	if (_listeningSocket != nil)
		@throw [OFAlreadyConnectedException exception];

	_port = port;
}

- (uint16_t)port
{
	return _port;
}

#ifdef OF_HAVE_THREADS
- (void)setNumberOfThreads: (size_t)numberOfThreads
{
	if (numberOfThreads == 0)
		@throw [OFInvalidArgumentException exception];

	if (_listeningSocket != nil)
		@throw [OFAlreadyConnectedException exception];

	_numberOfThreads = numberOfThreads;
}

- (size_t)numberOfThreads
{
	return _numberOfThreads;
}
#endif

- (void)start
{
	void *pool = objc_autoreleasePoolPush();

	if (_host == nil)
		@throw [OFInvalidArgumentException exception];

	if (_listeningSocket != nil)
		@throw [OFAlreadyConnectedException exception];

	_listeningSocket = [[OFTCPSocket alloc] init];
	_port = [_listeningSocket bindToHost: _host port: _port];
	[_listeningSocket listen];

#ifdef OF_HAVE_THREADS
	if (_numberOfThreads > 1) {
		OFMutableArray *threads =
		    [OFMutableArray arrayWithCapacity: _numberOfThreads - 1];

		for (size_t i = 1; i < _numberOfThreads; i++) {
			OFHTTPServerThread *thread =
			    [OFHTTPServerThread thread];
			thread.supportsSockets = true;

			[thread start];
			[threads addObject: thread];
		}

		[threads makeImmutable];
		_threadPool = [threads copy];
	}
#endif

	_listeningSocket.delegate = self;
	[_listeningSocket asyncAccept];

	objc_autoreleasePoolPop(pool);
}

- (void)stop
{
	[_listeningSocket cancelAsyncRequests];
	[_listeningSocket release];
	_listeningSocket = nil;

#ifdef OF_HAVE_THREADS
	for (OFHTTPServerThread *thread in _threadPool)
		[thread stop];

	[_threadPool release];
	_threadPool = nil;
#endif
}

- (void)of_handleAcceptedSocket: (OFStreamSocket *)acceptedSocket
{
	OFHTTPServerConnection *connection = [[[OFHTTPServerConnection alloc]
	    initWithSocket: acceptedSocket
		    server: self] autorelease];

	acceptedSocket.delegate = connection;
	[acceptedSocket asyncReadLine];
}

-    (bool)socket: (OFStreamSocket *)sock
  didAcceptSocket: (OFStreamSocket *)acceptedSocket
	exception: (id)exception
{
	if (exception != nil) {
		if (![_delegate respondsToSelector:
		    @selector(server:didReceiveExceptionOnListeningSocket:)])
			return false;

		return [_delegate server: self
		    didReceiveExceptionOnListeningSocket: exception];
	}

#ifdef OF_HAVE_THREADS
	if (_numberOfThreads > 1) {
		OFHTTPServerThread *thread =
		    [_threadPool objectAtIndex: _nextThreadIndex];

		if (++_nextThreadIndex >= _numberOfThreads - 1)
			_nextThreadIndex = 0;

		[self performSelector: @selector(of_handleAcceptedSocket:)
			     onThread: thread
			   withObject: acceptedSocket
			waitUntilDone: false];
	} else
#endif
		[self of_handleAcceptedSocket: acceptedSocket];

	return true;
}
@end