/* * Copyright (c) 2008-2023 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> #import "OFGnuTLSTLSStream.h" #import "OFData.h" #import "OFStream+Private.h" #import "OFAlreadyOpenException.h" #import "OFInitializationFailedException.h" #import "OFNotOpenException.h" #import "OFReadFailedException.h" #import "OFTLSHandshakeFailedException.h" #import "OFWriteFailedException.h" int _ObjFWTLS_reference; static gnutls_certificate_credentials_t systemTrustCreds; #ifndef GNUTLS_SAFE_PADDING_CHECK /* Some older versions don't have it. */ # define GNUTLS_SAFE_PADDING_CHECK 0 #endif @implementation OFGnuTLSTLSStream static ssize_t readFunc(gnutls_transport_ptr_t transport, void *buffer, size_t length) { OFGnuTLSTLSStream *stream = (OFGnuTLSTLSStream *)transport; @try { length = [stream.underlyingStream readIntoBuffer: buffer length: length]; } @catch (OFReadFailedException *e) { gnutls_transport_set_errno(stream->_session, e.errNo); return -1; } if (length == 0 && !stream.underlyingStream.atEndOfStream) { gnutls_transport_set_errno(stream->_session, EAGAIN); return -1; } return length; } static ssize_t writeFunc(gnutls_transport_ptr_t transport, const void *buffer, size_t length) { OFGnuTLSTLSStream *stream = (OFGnuTLSTLSStream *)transport; @try { [stream.underlyingStream writeBuffer: buffer length: length]; } @catch (OFWriteFailedException *e) { gnutls_transport_set_errno(stream->_session, e.errNo); if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN) return e.bytesWritten; return -1; } return length; } + (void)load { if (OFTLSStreamImplementation == Nil) OFTLSStreamImplementation = self; } + (void)initialize { if (self != [OFGnuTLSTLSStream class]) return; if (gnutls_certificate_allocate_credentials(&systemTrustCreds) != GNUTLS_E_SUCCESS || gnutls_certificate_set_x509_system_trust(systemTrustCreds) < 0) @throw [OFInitializationFailedException exception]; } - (instancetype)initWithStream: (OFStream <OFReadyForReadingObserving, OFReadyForWritingObserving> *)stream { self = [super initWithStream: stream]; @try { _underlyingStream.delegate = self; } @catch (id e) { [self release]; @throw e; } return self; } - (void)dealloc { if (_initialized) [self close]; [_host release]; [super dealloc]; } - (void)close { if (!_initialized) @throw [OFNotOpenException exceptionWithObject: self]; if (_handshakeDone) gnutls_bye(_session, GNUTLS_SHUT_WR); gnutls_deinit(_session); _initialized = false; [_host release]; _host = nil; [super close]; } - (size_t)lowlevelReadIntoBuffer: (void *)buffer length: (size_t)length { ssize_t ret; if (!_handshakeDone) @throw [OFNotOpenException exceptionWithObject: self]; if ((ret = gnutls_record_recv(_session, buffer, length)) < 0) { /* * The underlying stream might have had data ready, but not * enough for GnuTLS to return decrypted data. This means the * caller might have observed the TLS stream for reading, got a * ready signal and read - and expects the read to succeed, not * to fail with EWOULDBLOCK/EAGAIN, as it was signaled ready. * Therefore, return 0, as we could read 0 decrypted bytes, but * cleared the ready signal of the underlying stream. */ if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN) return 0; /* FIXME: Translate error to errNo */ @throw [OFReadFailedException exceptionWithObject: self requestedLength: length errNo: 0]; } return ret; } - (size_t)lowlevelWriteBuffer: (const void *)buffer length: (size_t)length { ssize_t ret; if (!_handshakeDone) @throw [OFNotOpenException exceptionWithObject: self]; if ((ret = gnutls_record_send(_session, buffer, length)) < 0) { if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN) return 0; /* FIXME: Translate error to errNo */ @throw [OFWriteFailedException exceptionWithObject: self requestedLength: length bytesWritten: ret errNo: 0]; } return ret; } - (bool)hasDataInReadBuffer { if (gnutls_record_check_pending(_session) > 0) return true; return super.hasDataInReadBuffer; } - (bool)of_isWaitingForDelimiter { /* FIXME: There should be a non-private API for this. */ /* * If we still have pending data in the session, we haven't processed * it yet to see if our delimiter is in there. So return false here, as * that will signal the stream as ready for reading, which in turn will * cause a read and checking for the delimiter. */ if (gnutls_record_check_pending(_session) > 0) return false; return super.of_waitingForDelimiter; } - (void)asyncPerformClientHandshakeWithHost: (OFString *)host runLoopMode: (OFRunLoopMode)runLoopMode { static const OFTLSStreamErrorCode initFailedErrorCode = OFTLSStreamErrorCodeInitializationFailed; id exception = nil; int status; if (_initialized) @throw [OFAlreadyOpenException exceptionWithObject: self]; if (gnutls_init(&_session, GNUTLS_CLIENT | GNUTLS_NONBLOCK | GNUTLS_SAFE_PADDING_CHECK) != GNUTLS_E_SUCCESS) @throw [OFTLSHandshakeFailedException exceptionWithStream: self host: host errorCode: initFailedErrorCode]; _initialized = true; gnutls_transport_set_ptr(_session, self); gnutls_transport_set_pull_function(_session, readFunc); gnutls_transport_set_push_function(_session, writeFunc); if (gnutls_set_default_priority(_session) != GNUTLS_E_SUCCESS || gnutls_credentials_set(_session, GNUTLS_CRD_CERTIFICATE, systemTrustCreds) != GNUTLS_E_SUCCESS) @throw [OFTLSHandshakeFailedException exceptionWithStream: self host: host errorCode: initFailedErrorCode]; _host = [host copy]; if (gnutls_server_name_set(_session, GNUTLS_NAME_DNS, _host.UTF8String, _host.UTF8StringLength) != GNUTLS_E_SUCCESS) @throw [OFTLSHandshakeFailedException exceptionWithStream: self host: host errorCode: initFailedErrorCode]; if (_verifiesCertificates) gnutls_session_set_verify_cert(_session, _host.UTF8String, 0); status = gnutls_handshake(_session); if (status == GNUTLS_E_INTERRUPTED || status == GNUTLS_E_AGAIN) { if (gnutls_record_get_direction(_session) == 1) [_underlyingStream asyncWriteData: [OFData dataWithItems: "" count: 0] runLoopMode: runLoopMode]; else [_underlyingStream asyncReadIntoBuffer: (void *)"" length: 0 runLoopMode: runLoopMode]; [_delegate retain]; return; } if (status == GNUTLS_E_SUCCESS) _handshakeDone = true; else /* FIXME: Map to better errors */ exception = [OFTLSHandshakeFailedException exceptionWithStream: self host: host errorCode: OFTLSStreamErrorCodeUnknown]; if ([_delegate respondsToSelector: @selector(stream:didPerformClientHandshakeWithHost:exception:)]) [_delegate stream: self didPerformClientHandshakeWithHost: host exception: exception]; } - (bool)stream: (OFStream *)stream didReadIntoBuffer: (void *)buffer length: (size_t)length exception: (nullable id)exception { if (exception == nil) { int status = gnutls_handshake(_session); if (status == GNUTLS_E_INTERRUPTED || status == GNUTLS_E_AGAIN) { if (gnutls_record_get_direction(_session) == 1) { OFData *data = [OFData dataWithItems: "" count: 0]; OFRunLoopMode runLoopMode = [OFRunLoop currentRunLoop].currentMode; [_underlyingStream asyncWriteData: data runLoopMode: runLoopMode]; return false; } else return true; } if (status == GNUTLS_E_SUCCESS) _handshakeDone = true; else exception = [OFTLSHandshakeFailedException exceptionWithStream: self host: _host errorCode: OFTLSStreamErrorCodeUnknown]; } if ([_delegate respondsToSelector: @selector(stream:didPerformClientHandshakeWithHost:exception:)]) [_delegate stream: self didPerformClientHandshakeWithHost: _host exception: exception]; [_delegate release]; return false; } - (OFData *)stream: (OFStream *)stream didWriteData: (OFData *)data bytesWritten: (size_t)bytesWritten exception: (id)exception { if (exception == nil) { int status = gnutls_handshake(_session); if (status == GNUTLS_E_INTERRUPTED || status == GNUTLS_E_AGAIN) { if (gnutls_record_get_direction(_session) == 1) return data; else { OFRunLoopMode runLoopMode = [OFRunLoop currentRunLoop].currentMode; [_underlyingStream asyncReadIntoBuffer: (void *)"" length: 0 runLoopMode: runLoopMode]; return nil; } } if (status == GNUTLS_E_SUCCESS) _handshakeDone = true; else exception = [OFTLSHandshakeFailedException exceptionWithStream: self host: _host errorCode: OFTLSStreamErrorCodeUnknown]; } if ([_delegate respondsToSelector: @selector(stream:didPerformClientHandshakeWithHost:exception:)]) [_delegate stream: self didPerformClientHandshakeWithHost: _host exception: exception]; [_delegate release]; return nil; } @end