FreeRDP/libfreerdp/core/transport.c

1420 lines
29 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
* Network Transport Layer
*
* Copyright 2011 Vic Lee
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <winpr/crt.h>
#include <winpr/synch.h>
#include <winpr/print.h>
#include <winpr/stream.h>
#include <freerdp/error.h>
#include <freerdp/utils/tcp.h>
#include <freerdp/utils/ringbuffer.h>
#include <openssl/bio.h>
#include <time.h>
#include <errno.h>
#include <fcntl.h>
#ifndef _WIN32
#include <netdb.h>
#include <sys/socket.h>
#include <sys/select.h>
#include <sys/time.h>
#endif
#ifdef HAVE_VALGRIND_MEMCHECK_H
#include <valgrind/memcheck.h>
#endif
#include "tpkt.h"
#include "fastpath.h"
#include "transport.h"
#include "rdp.h"
#define BUFFER_SIZE 16384
static void* transport_client_thread(void* arg);
wStream* transport_send_stream_init(rdpTransport* transport, int size)
{
wStream* s;
s = StreamPool_Take(transport->ReceivePool, size);
Stream_EnsureCapacity(s, size);
Stream_SetPosition(s, 0);
return s;
}
void transport_attach(rdpTransport* transport, int sockfd)
{
tcp_attach(transport->TcpIn, sockfd);
transport->SplitInputOutput = FALSE;
transport->TcpOut = transport->TcpIn;
transport->frontBio = transport->TcpIn->bufferedBio;
}
void transport_stop(rdpTransport* transport)
{
if (transport->async)
{
if (transport->stopEvent)
{
SetEvent(transport->stopEvent);
WaitForSingleObject(transport->thread, INFINITE);
CloseHandle(transport->thread);
CloseHandle(transport->stopEvent);
transport->thread = NULL;
transport->stopEvent = NULL;
}
}
}
BOOL transport_disconnect(rdpTransport* transport)
{
BOOL status = TRUE;
if (!transport)
return FALSE;
transport_stop(transport);
BIO_free_all(transport->frontBio);
transport->frontBio = 0;
return status;
}
BOOL transport_connect_rdp(rdpTransport* transport)
{
/* RDP encryption */
return TRUE;
}
long transport_bio_tsg_callback(BIO* bio, int mode, const char* argp, int argi, long argl, long ret)
{
return 1;
}
static int transport_bio_tsg_write(BIO* bio, const char* buf, int num)
{
int status;
rdpTsg* tsg;
tsg = (rdpTsg*) bio->ptr;
BIO_clear_retry_flags(bio);
status = tsg_write(tsg, (BYTE*) buf, num);
if (status > 0)
return status;
if (status == 0)
BIO_set_retry_write(bio);
return -1;
}
static int transport_bio_tsg_read(BIO* bio, char* buf, int size)
{
int status;
rdpTsg* tsg;
tsg = (rdpTsg*) bio->ptr;
status = tsg_read(bio->ptr, (BYTE*) buf, size);
BIO_clear_retry_flags(bio);
if (status == 0)
{
BIO_set_retry_read(bio);
status = -1;
}
else if (status == -1)
{
status = 0;
}
return status >= 0 ? status : -1;
}
static int transport_bio_tsg_puts(BIO* bio, const char* str)
{
return 1;
}
static int transport_bio_tsg_gets(BIO* bio, char* str, int size)
{
return 1;
}
static long transport_bio_tsg_ctrl(BIO* bio, int cmd, long arg1, void* arg2)
{
if (cmd == BIO_CTRL_FLUSH)
{
return 1;
}
return 0;
}
static int transport_bio_tsg_new(BIO* bio)
{
bio->init = 1;
bio->num = 0;
bio->ptr = NULL;
bio->flags = 0;
return 1;
}
static int transport_bio_tsg_free(BIO* bio)
{
return 1;
}
#define BIO_TYPE_TSG 65
static BIO_METHOD transport_bio_tsg_methods =
{
BIO_TYPE_TSG,
"TSGateway",
transport_bio_tsg_write,
transport_bio_tsg_read,
transport_bio_tsg_puts,
transport_bio_tsg_gets,
transport_bio_tsg_ctrl,
transport_bio_tsg_new,
transport_bio_tsg_free,
NULL,
};
BIO_METHOD* BIO_s_tsg(void)
{
return &transport_bio_tsg_methods;
}
BOOL transport_connect_tls(rdpTransport* transport)
{
rdpSettings *settings = transport->settings;
rdpTls *targetTls;
BIO *targetBio;
int tls_status;
freerdp* instance;
rdpContext* context;
instance = (freerdp*) transport->settings->instance;
context = instance->context;
if (transport->layer == TRANSPORT_LAYER_TSG)
{
transport->TsgTls = tls_new(transport->settings);
transport->layer = TRANSPORT_LAYER_TSG_TLS;
targetTls = transport->TsgTls;
targetBio = transport->frontBio;
}
else
{
if (!transport->TlsIn)
transport->TlsIn = tls_new(settings);
if (!transport->TlsOut)
transport->TlsOut = transport->TlsIn;
targetTls = transport->TlsIn;
targetBio = transport->TcpIn->bufferedBio;
transport->layer = TRANSPORT_LAYER_TLS;
}
targetTls->hostname = settings->ServerHostname;
targetTls->port = settings->ServerPort;
if (targetTls->port == 0)
targetTls->port = 3389;
tls_status = tls_connect(targetTls, targetBio);
if (tls_status < 1)
{
if (tls_status < 0)
{
if (!connectErrorCode)
connectErrorCode = TLSCONNECTERROR;
if (!freerdp_get_last_error(context))
freerdp_set_last_error(context, FREERDP_ERROR_TLS_CONNECT_FAILED);
}
else
{
if (!freerdp_get_last_error(context))
freerdp_set_last_error(context, FREERDP_ERROR_CONNECT_CANCELLED);
}
return FALSE;
}
transport->frontBio = targetTls->bio;
if (!transport->frontBio)
{
fprintf(stderr, "%s: unable to prepend a filtering TLS bio", __FUNCTION__);
return FALSE;
}
return TRUE;
}
BOOL transport_connect_nla(rdpTransport* transport)
{
freerdp* instance;
rdpSettings* settings;
rdpCredssp *credSsp;
settings = transport->settings;
instance = (freerdp*) settings->instance;
if (!transport_connect_tls(transport))
return FALSE;
/* Network Level Authentication */
if (!settings->Authentication)
return TRUE;
if (!transport->credssp)
{
transport->credssp = credssp_new(instance, transport, settings);
if (!transport->credssp)
return FALSE;
transport_set_nla_mode(transport, TRUE);
if (settings->AuthenticationServiceClass)
{
transport->credssp->ServicePrincipalName =
credssp_make_spn(settings->AuthenticationServiceClass, settings->ServerHostname);
if (!transport->credssp->ServicePrincipalName)
return FALSE;
}
}
credSsp = transport->credssp;
if (credssp_authenticate(credSsp) < 0)
{
if (!connectErrorCode)
connectErrorCode = AUTHENTICATIONERROR;
if (!freerdp_get_last_error(instance->context))
{
freerdp_set_last_error(instance->context, FREERDP_ERROR_AUTHENTICATION_FAILED);
}
fprintf(stderr, "Authentication failure, check credentials.\n"
"If credentials are valid, the NTLMSSP implementation may be to blame.\n");
transport_set_nla_mode(transport, FALSE);
credssp_free(credSsp);
transport->credssp = NULL;
return FALSE;
}
transport_set_nla_mode(transport, FALSE);
credssp_free(credSsp);
transport->credssp = NULL;
return TRUE;
}
BOOL transport_tsg_connect(rdpTransport* transport, const char* hostname, UINT16 port)
{
rdpTsg* tsg;
int tls_status;
freerdp* instance;
rdpContext* context;
rdpSettings *settings = transport->settings;
instance = (freerdp*) transport->settings->instance;
context = instance->context;
tsg = tsg_new(transport);
if (!tsg)
return FALSE;
tsg->transport = transport;
transport->tsg = tsg;
transport->SplitInputOutput = TRUE;
if (!transport->TlsIn)
{
transport->TlsIn = tls_new(settings);
if (!transport->TlsIn)
return FALSE;
}
if (!transport->TlsOut)
{
transport->TlsOut = tls_new(settings);
if (!transport->TlsOut)
return FALSE;
}
/* put a decent default value for gateway port */
if (!settings->GatewayPort)
settings->GatewayPort = 443;
transport->TlsIn->hostname = transport->TlsOut->hostname = settings->GatewayHostname;
transport->TlsIn->port = transport->TlsOut->port = settings->GatewayPort;
tls_status = tls_connect(transport->TlsIn, transport->TcpIn->bufferedBio);
if (tls_status < 1)
{
if (tls_status < 0)
{
if (!freerdp_get_last_error(context))
freerdp_set_last_error(context, FREERDP_ERROR_TLS_CONNECT_FAILED);
}
else
{
if (!freerdp_get_last_error(context))
freerdp_set_last_error(context, FREERDP_ERROR_CONNECT_CANCELLED);
}
return FALSE;
}
tls_status = tls_connect(transport->TlsOut, transport->TcpOut->bufferedBio);
if (tls_status < 1)
{
if (tls_status < 0)
{
if (!freerdp_get_last_error(context))
freerdp_set_last_error(context, FREERDP_ERROR_TLS_CONNECT_FAILED);
}
else
{
if (!freerdp_get_last_error(context))
freerdp_set_last_error(context, FREERDP_ERROR_CONNECT_CANCELLED);
}
return FALSE;
}
if (!tsg_connect(tsg, hostname, port))
return FALSE;
transport->frontBio = BIO_new(BIO_s_tsg());
transport->frontBio->ptr = tsg;
return TRUE;
}
BOOL transport_connect(rdpTransport* transport, const char* hostname, UINT16 port)
{
BOOL status = FALSE;
rdpSettings* settings = transport->settings;
transport->async = settings->AsyncTransport;
if (transport->GatewayEnabled)
{
transport->layer = TRANSPORT_LAYER_TSG;
transport->SplitInputOutput = TRUE;
transport->TcpOut = tcp_new(settings);
if (!tcp_connect(transport->TcpIn, settings->GatewayHostname, settings->GatewayPort) ||
!tcp_set_blocking_mode(transport->TcpIn, FALSE))
return FALSE;
if (!tcp_connect(transport->TcpOut, settings->GatewayHostname, settings->GatewayPort) ||
!tcp_set_blocking_mode(transport->TcpOut, FALSE))
return FALSE;
if (!transport_tsg_connect(transport, hostname, port))
return FALSE;
status = TRUE;
}
else
{
status = tcp_connect(transport->TcpIn, hostname, port);
transport->SplitInputOutput = FALSE;
transport->TcpOut = transport->TcpIn;
transport->frontBio = transport->TcpIn->bufferedBio;
}
if (status)
{
if (transport->async)
{
transport->stopEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
transport->thread = CreateThread(NULL, 0,
(LPTHREAD_START_ROUTINE) transport_client_thread, transport, 0, NULL);
}
}
return status;
}
BOOL transport_accept_rdp(rdpTransport* transport)
{
/* RDP encryption */
return TRUE;
}
BOOL transport_accept_tls(rdpTransport* transport)
{
if (!transport->TlsIn)
transport->TlsIn = tls_new(transport->settings);
if (!transport->TlsOut)
transport->TlsOut = transport->TlsIn;
transport->layer = TRANSPORT_LAYER_TLS;
if (!tls_accept(transport->TlsIn, transport->TcpIn->bufferedBio, transport->settings->CertificateFile, transport->settings->PrivateKeyFile))
return FALSE;
transport->frontBio = transport->TlsIn->bio;
return TRUE;
}
BOOL transport_accept_nla(rdpTransport* transport)
{
freerdp* instance;
rdpSettings* settings;
settings = transport->settings;
instance = (freerdp*) settings->instance;
if (!transport->TlsIn)
transport->TlsIn = tls_new(transport->settings);
if (!transport->TlsOut)
transport->TlsOut = transport->TlsIn;
transport->layer = TRANSPORT_LAYER_TLS;
if (!tls_accept(transport->TlsIn, transport->TcpIn->bufferedBio, settings->CertificateFile, settings->PrivateKeyFile))
return FALSE;
transport->frontBio = transport->TlsIn->bio;
/* Network Level Authentication */
if (!settings->Authentication)
return TRUE;
if (!transport->credssp)
{
transport->credssp = credssp_new(instance, transport, settings);
transport_set_nla_mode(transport, TRUE);
}
if (credssp_authenticate(transport->credssp) < 0)
{
fprintf(stderr, "client authentication failure\n");
transport_set_nla_mode(transport, FALSE);
credssp_free(transport->credssp);
transport->credssp = NULL;
tls_set_alert_code(transport->TlsIn, TLS_ALERT_LEVEL_FATAL, TLS_ALERT_DESCRIPTION_ACCESS_DENIED);
return FALSE;
}
/* don't free credssp module yet, we need to copy the credentials from it first */
transport_set_nla_mode(transport, FALSE);
return TRUE;
}
BOOL nla_verify_header(wStream* s)
{
if ((Stream_Pointer(s)[0] == 0x30) && (Stream_Pointer(s)[1] & 0x80))
return TRUE;
return FALSE;
}
UINT32 nla_read_header(wStream* s)
{
UINT32 length = 0;
if (Stream_Pointer(s)[1] & 0x80)
{
if ((Stream_Pointer(s)[1] & ~(0x80)) == 1)
{
length = Stream_Pointer(s)[2];
length += 3;
Stream_Seek(s, 3);
}
else if ((Stream_Pointer(s)[1] & ~(0x80)) == 2)
{
length = (Stream_Pointer(s)[2] << 8) | Stream_Pointer(s)[3];
length += 4;
Stream_Seek(s, 4);
}
else
{
fprintf(stderr, "Error reading TSRequest!\n");
}
}
else
{
length = Stream_Pointer(s)[1];
length += 2;
Stream_Seek(s, 2);
}
return length;
}
UINT32 nla_header_length(wStream* s)
{
UINT32 length = 0;
if (Stream_Pointer(s)[1] & 0x80)
{
if ((Stream_Pointer(s)[1] & ~(0x80)) == 1)
length = 3;
else if ((Stream_Pointer(s)[1] & ~(0x80)) == 2)
length = 4;
else
fprintf(stderr, "Error reading TSRequest!\n");
}
else
{
length = 2;
}
return length;
}
static int transport_wait_for_read(rdpTransport* transport)
{
struct timeval tv;
fd_set rset, wset;
fd_set *rsetPtr = NULL, *wsetPtr = NULL;
rdpTcp *tcpIn;
tcpIn = transport->TcpIn;
if (tcpIn->readBlocked)
{
rsetPtr = &rset;
FD_ZERO(rsetPtr);
FD_SET(tcpIn->sockfd, rsetPtr);
}
else if (tcpIn->writeBlocked)
{
wsetPtr = &wset;
FD_ZERO(wsetPtr);
FD_SET(tcpIn->sockfd, wsetPtr);
}
if (!wsetPtr && !rsetPtr)
{
USleep(1000);
return 0;
}
tv.tv_sec = 0;
tv.tv_usec = 1000;
return select(tcpIn->sockfd + 1, rsetPtr, wsetPtr, NULL, &tv);
}
static int transport_wait_for_write(rdpTransport* transport)
{
struct timeval tv;
fd_set rset, wset;
fd_set *rsetPtr = NULL, *wsetPtr = NULL;
rdpTcp *tcpOut;
tcpOut = transport->SplitInputOutput ? transport->TcpOut : transport->TcpIn;
if (tcpOut->writeBlocked)
{
wsetPtr = &wset;
FD_ZERO(wsetPtr);
FD_SET(tcpOut->sockfd, wsetPtr);
}
else if (tcpOut->readBlocked)
{
rsetPtr = &rset;
FD_ZERO(rsetPtr);
FD_SET(tcpOut->sockfd, rsetPtr);
}
if (!wsetPtr && !rsetPtr)
{
USleep(1000);
return 0;
}
tv.tv_sec = 0;
tv.tv_usec = 1000;
return select(tcpOut->sockfd + 1, rsetPtr, wsetPtr, NULL, &tv);
}
int transport_read_layer(rdpTransport* transport, BYTE* data, int bytes)
{
int read = 0;
int status = -1;
while (read < bytes)
{
status = BIO_read(transport->frontBio, data + read, bytes - read);
if (!status)
{
transport->layer = TRANSPORT_LAYER_CLOSED;
return -1;
}
if (status < 0)
{
if (!BIO_should_retry(transport->frontBio))
{
/* something unexpected happened, let's close */
transport->layer = TRANSPORT_LAYER_CLOSED;
return -1;
}
/* non blocking will survive a partial read */
if (!transport->blocking)
return read;
/* blocking means that we can't continue until we have read the number of
* requested bytes */
if (transport_wait_for_read(transport) < 0)
{
fprintf(stderr, "%s: error when selecting for read\n", __FUNCTION__);
return -1;
}
continue;
}
#ifdef HAVE_VALGRIND_MEMCHECK_H
VALGRIND_MAKE_MEM_DEFINED(data + read, bytes - read);
#endif
read += status;
}
return read;
}
int transport_read(rdpTransport* transport, wStream* s)
{
int status;
int position;
int pduLength;
BYTE *header;
int transport_status;
position = 0;
pduLength = 0;
transport_status = 0;
if (!transport)
return -1;
if (!s)
return -1;
/* first check if we have header */
position = Stream_GetPosition(s);
if (position < 4)
{
status = transport_read_layer(transport, Stream_Buffer(s) + position, 4 - position);
if (status < 0)
return status;
transport_status += status;
if ((status + position) < 4)
return transport_status;
position += status;
}
header = Stream_Buffer(s);
/* if header is present, read exactly one PDU */
if (transport->NlaMode)
{
if (header[0] == 0x30)
{
/* TSRequest (NLA) */
if (header[1] & 0x80)
{
if ((header[1] & ~(0x80)) == 1)
{
pduLength = header[2];
pduLength += 3;
}
else if ((header[1] & ~(0x80)) == 2)
{
pduLength = (header[2] << 8) | header[3];
pduLength += 4;
}
else
{
fprintf(stderr, "Error reading TSRequest!\n");
return -1;
}
}
else
{
pduLength = header[1];
pduLength += 2;
}
}
}
else
{
if (header[0] == 0x03)
{
/* TPKT header */
pduLength = (header[2] << 8) | header[3];
}
else
{
/* Fast-Path Header */
if (header[1] & 0x80)
pduLength = ((header[1] & 0x7F) << 8) | header[2];
else
pduLength = header[1];
}
}
status = transport_read_layer(transport, Stream_Buffer(s) + position, pduLength - position);
if (status < 0)
return status;
transport_status += status;
#ifdef WITH_DEBUG_TRANSPORT
/* dump when whole PDU is read */
if (position + status >= pduLength)
{
fprintf(stderr, "Local < Remote\n");
winpr_HexDump(Stream_Buffer(s), pduLength);
}
#endif
if (position + status >= pduLength)
{
WLog_Packet(transport->log, WLOG_TRACE, Stream_Buffer(s), pduLength, WLOG_PACKET_INBOUND);
}
return transport_status;
}
static int transport_read_nonblocking(rdpTransport* transport)
{
int status;
status = transport_read(transport, transport->ReceiveBuffer);
if (status <= 0)
return status;
Stream_Seek(transport->ReceiveBuffer, status);
return status;
}
BOOL transport_bio_buffered_drain(BIO *bio);
int transport_write(rdpTransport* transport, wStream* s)
{
int length;
int status = -1;
EnterCriticalSection(&(transport->WriteLock));
length = Stream_GetPosition(s);
Stream_SetPosition(s, 0);
#ifdef WITH_DEBUG_TRANSPORT
if (length > 0)
{
fprintf(stderr, "Local > Remote\n");
winpr_HexDump(Stream_Buffer(s), length);
}
#endif
if (length > 0)
{
WLog_Packet(transport->log, WLOG_TRACE, Stream_Buffer(s), length, WLOG_PACKET_OUTBOUND);
}
while (length > 0)
{
status = BIO_write(transport->frontBio, Stream_Pointer(s), length);
if (status <= 0)
{
/* the buffered BIO that is at the end of the chain always says OK for writing,
* so a retry means that for any reason we need to read. The most probable
* is a SSL or TSG BIO in the chain.
*/
if (!BIO_should_retry(transport->frontBio))
return status;
/* non-blocking can live with blocked IOs */
if (!transport->blocking)
return status;
if (transport_wait_for_write(transport) < 0)
{
fprintf(stderr, "%s: error when selecting for write\n", __FUNCTION__);
return -1;
}
continue;
}
if (transport->blocking || transport->settings->WaitForOutputBufferFlush)
{
/* blocking transport, we must ensure the write buffer is really empty */
rdpTcp *out = transport->TcpOut;
while (out->writeBlocked)
{
if (transport_wait_for_write(transport) < 0)
{
fprintf(stderr, "%s: error when selecting for write\n", __FUNCTION__);
return -1;
}
if (!transport_bio_buffered_drain(out->bufferedBio))
{
fprintf(stderr, "%s: error when draining outputBuffer\n", __FUNCTION__);
return -1;
}
}
}
length -= status;
Stream_Seek(s, status);
}
if (status < 0)
{
/* A write error indicates that the peer has dropped the connection */
transport->layer = TRANSPORT_LAYER_CLOSED;
}
if (s->pool)
Stream_Release(s);
LeaveCriticalSection(&(transport->WriteLock));
return status;
}
void transport_get_fds(rdpTransport* transport, void** rfds, int* rcount)
{
void* pfd;
#ifdef _WIN32
rfds[*rcount] = transport->TcpIn->wsa_event;
(*rcount)++;
if (transport->SplitInputOutput)
{
rfds[*rcount] = transport->TcpOut->wsa_event;
(*rcount)++;
}
#else
rfds[*rcount] = (void*)(long)(transport->TcpIn->sockfd);
(*rcount)++;
if (transport->SplitInputOutput)
{
rfds[*rcount] = (void*)(long)(transport->TcpOut->sockfd);
(*rcount)++;
}
#endif
pfd = GetEventWaitObject(transport->ReceiveEvent);
if (pfd)
{
rfds[*rcount] = pfd;
(*rcount)++;
}
if (transport->GatewayEvent)
{
pfd = GetEventWaitObject(transport->GatewayEvent);
if (pfd)
{
rfds[*rcount] = pfd;
(*rcount)++;
}
}
}
void transport_get_read_handles(rdpTransport* transport, HANDLE* events, DWORD* count)
{
events[*count] = tcp_get_event_handle(transport->TcpIn);
(*count)++;
if (transport->SplitInputOutput)
{
events[*count] = tcp_get_event_handle(transport->TcpOut);
(*count)++;
}
if (transport->ReceiveEvent)
{
events[*count] = transport->ReceiveEvent;
(*count)++;
}
if (transport->GatewayEvent)
{
events[*count] = transport->GatewayEvent;
(*count)++;
}
}
BOOL tranport_is_write_blocked(rdpTransport* transport)
{
if (transport->TcpIn->writeBlocked)
return TRUE;
return transport->SplitInputOutput &&
transport->TcpOut &&
transport->TcpOut->writeBlocked;
}
int tranport_drain_output_buffer(rdpTransport* transport)
{
BOOL ret = FALSE;
/* First try to send some accumulated bytes in the send buffer */
if (transport->TcpIn->writeBlocked)
{
if (!transport_bio_buffered_drain(transport->TcpIn->bufferedBio))
return -1;
ret |= transport->TcpIn->writeBlocked;
}
if (transport->SplitInputOutput && transport->TcpOut && transport->TcpOut->writeBlocked)
{
if (!transport_bio_buffered_drain(transport->TcpOut->bufferedBio))
return -1;
ret |= transport->TcpOut->writeBlocked;
}
return ret;
}
int transport_check_fds(rdpTransport* transport)
{
int pos;
int status;
int length;
int recv_status;
wStream* received;
if (!transport)
return -1;
#ifdef _WIN32
WSAResetEvent(transport->TcpIn->wsa_event);
#endif
ResetEvent(transport->ReceiveEvent);
/**
* Loop through and read all available PDUs. Since multiple
* PDUs can exist, it's important to deliver them all before
* returning. Otherwise we run the risk of having a thread
* wait for a socket to get signaled that data is available
* (which may never happen).
*/
for (;;)
{
/**
* Note: transport_read_nonblocking() reads max 1 additional PDU from
* the layer. Also note that transport_read_nonblocking() is also called
* outside of this function in transport_write()! This means that when
* entering transport_check_fds it is possible that the stream position
* of transport->ReceiveBuffer position is > 0. We must process this data
* even if transport_read_nonblocking() returns 0.
* Note that transport->ReceiveBuffer is replaced after each iteration
* of this loop with a fresh stream instance from a pool.
*/
if ((status = transport_read_nonblocking(transport)) < 0)
return status;
if ((pos = Stream_GetPosition(transport->ReceiveBuffer)) < 2)
return status;
Stream_SetPosition(transport->ReceiveBuffer, 0);
length = 0;
if (transport->NlaMode)
{
if (nla_verify_header(transport->ReceiveBuffer))
{
/* TSRequest */
/* Ensure the TSRequest header is available. */
if (pos <= 4)
{
Stream_SetPosition(transport->ReceiveBuffer, pos);
return 0;
}
/* TSRequest header can be 2, 3 or 4 bytes long */
length = nla_header_length(transport->ReceiveBuffer);
if (pos < length)
{
Stream_SetPosition(transport->ReceiveBuffer, pos);
return 0;
}
length = nla_read_header(transport->ReceiveBuffer);
}
}
else
{
if (tpkt_verify_header(transport->ReceiveBuffer)) /* TPKT */
{
/* Ensure the TPKT header is available. */
if (pos <= 4)
{
Stream_SetPosition(transport->ReceiveBuffer, pos);
return 0;
}
length = tpkt_read_header(transport->ReceiveBuffer);
}
else /* Fast Path */
{
/* Ensure the Fast Path header is available. */
if (pos <= 2)
{
Stream_SetPosition(transport->ReceiveBuffer, pos);
return 0;
}
/* Fastpath header can be two or three bytes long. */
length = fastpath_header_length(transport->ReceiveBuffer);
if (pos < length)
{
Stream_SetPosition(transport->ReceiveBuffer, pos);
return 0;
}
length = fastpath_read_header(NULL, transport->ReceiveBuffer);
}
}
if (length == 0)
{
fprintf(stderr, "transport_check_fds: protocol error, not a TPKT or Fast Path header.\n");
winpr_HexDump(Stream_Buffer(transport->ReceiveBuffer), pos);
return -1;
}
if (pos < length)
{
Stream_SetPosition(transport->ReceiveBuffer, pos);
return 0; /* Packet is not yet completely received. */
}
received = transport->ReceiveBuffer;
transport->ReceiveBuffer = StreamPool_Take(transport->ReceivePool, 0);
Stream_SetPosition(received, length);
Stream_SealLength(received);
Stream_SetPosition(received, 0);
/**
* status:
* -1: error
* 0: success
* 1: redirection
*/
recv_status = transport->ReceiveCallback(transport, received, transport->ReceiveExtra);
if (recv_status == 1)
{
return 1; /* session redirection */
}
Stream_Release(received);
if (recv_status < 0)
return -1;
}
return 0;
}
BOOL transport_set_blocking_mode(rdpTransport* transport, BOOL blocking)
{
BOOL status;
status = TRUE;
transport->blocking = blocking;
if (transport->SplitInputOutput)
{
status &= tcp_set_blocking_mode(transport->TcpIn, blocking);
status &= tcp_set_blocking_mode(transport->TcpOut, blocking);
}
else
{
status &= tcp_set_blocking_mode(transport->TcpIn, blocking);
}
if (transport->layer == TRANSPORT_LAYER_TSG || transport->layer == TRANSPORT_LAYER_TSG_TLS)
{
tsg_set_blocking_mode(transport->tsg, blocking);
}
return status;
}
void transport_set_gateway_enabled(rdpTransport* transport, BOOL GatewayEnabled)
{
transport->GatewayEnabled = GatewayEnabled;
}
void transport_set_nla_mode(rdpTransport* transport, BOOL NlaMode)
{
transport->NlaMode = NlaMode;
}
static void* transport_client_thread(void* arg)
{
DWORD status;
DWORD nCount;
HANDLE handles[8];
freerdp* instance;
rdpContext* context;
rdpTransport* transport;
transport = (rdpTransport*) arg;
assert(NULL != transport);
assert(NULL != transport->settings);
instance = (freerdp*) transport->settings->instance;
assert(NULL != instance);
context = instance->context;
assert(NULL != instance->context);
WLog_Print(transport->log, WLOG_DEBUG, "Starting transport thread");
nCount = 0;
handles[nCount++] = transport->stopEvent;
handles[nCount++] = transport->connectedEvent;
status = WaitForMultipleObjects(nCount, handles, FALSE, INFINITE);
if (WaitForSingleObject(transport->stopEvent, 0) == WAIT_OBJECT_0)
{
WLog_Print(transport->log, WLOG_DEBUG, "Terminating transport thread");
ExitThread(0);
return NULL;
}
WLog_Print(transport->log, WLOG_DEBUG, "Asynchronous transport activated");
while (1)
{
nCount = 0;
handles[nCount++] = transport->stopEvent;
transport_get_read_handles(transport, (HANDLE*) &handles, &nCount);
status = WaitForMultipleObjects(nCount, handles, FALSE, INFINITE);
if (transport->layer == TRANSPORT_LAYER_CLOSED)
{
rdpRdp* rdp = (rdpRdp*) transport->rdp;
rdp_set_error_info(rdp, ERRINFO_PEER_DISCONNECTED);
break;
}
else if (status != WAIT_TIMEOUT)
{
if (WaitForSingleObject(transport->stopEvent, 0) == WAIT_OBJECT_0)
break;
if (!freerdp_check_fds(instance))
break;
}
}
WLog_Print(transport->log, WLOG_DEBUG, "Terminating transport thread");
ExitThread(0);
return NULL;
}
rdpTransport* transport_new(rdpSettings* settings)
{
rdpTransport* transport;
transport = (rdpTransport *)calloc(1, sizeof(rdpTransport));
if (!transport)
return NULL;
WLog_Init();
transport->log = WLog_Get("com.freerdp.core.transport");
if (!transport->log)
goto out_free;
transport->TcpIn = tcp_new(settings);
if (!transport->TcpIn)
goto out_free;
transport->settings = settings;
/* a small 0.1ms delay when transport is blocking. */
transport->SleepInterval = 100;
transport->ReceivePool = StreamPool_New(TRUE, BUFFER_SIZE);
if (!transport->ReceivePool)
goto out_free_tcpin;
/* receive buffer for non-blocking read. */
transport->ReceiveBuffer = StreamPool_Take(transport->ReceivePool, 0);
if (!transport->ReceiveBuffer)
goto out_free_receivepool;
transport->ReceiveEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
if (!transport->ReceiveEvent || transport->ReceiveEvent == INVALID_HANDLE_VALUE)
goto out_free_receivebuffer;
transport->connectedEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
if (!transport->connectedEvent || transport->connectedEvent == INVALID_HANDLE_VALUE)
goto out_free_receiveEvent;
transport->blocking = TRUE;
transport->GatewayEnabled = FALSE;
transport->layer = TRANSPORT_LAYER_TCP;
if (!InitializeCriticalSectionAndSpinCount(&(transport->ReadLock), 4000))
goto out_free_connectedEvent;
if (!InitializeCriticalSectionAndSpinCount(&(transport->WriteLock), 4000))
goto out_free_readlock;
return transport;
out_free_readlock:
DeleteCriticalSection(&(transport->ReadLock));
out_free_connectedEvent:
CloseHandle(transport->connectedEvent);
out_free_receiveEvent:
CloseHandle(transport->ReceiveEvent);
out_free_receivebuffer:
StreamPool_Return(transport->ReceivePool, transport->ReceiveBuffer);
out_free_receivepool:
StreamPool_Free(transport->ReceivePool);
out_free_tcpin:
tcp_free(transport->TcpIn);
out_free:
free(transport);
return NULL;
}
void transport_free(rdpTransport* transport)
{
if (!transport)
return;
transport_stop(transport);
if (transport->ReceiveBuffer)
Stream_Release(transport->ReceiveBuffer);
StreamPool_Free(transport->ReceivePool);
CloseHandle(transport->ReceiveEvent);
CloseHandle(transport->connectedEvent);
if (transport->TlsIn)
tls_free(transport->TlsIn);
if (transport->TlsOut != transport->TlsIn)
tls_free(transport->TlsOut);
transport->TlsIn = NULL;
transport->TlsOut = NULL;
if (transport->TcpIn)
tcp_free(transport->TcpIn);
if (transport->TcpOut != transport->TcpIn)
tcp_free(transport->TcpOut);
transport->TcpIn = NULL;
transport->TcpOut = NULL;
tsg_free(transport->tsg);
transport->tsg = NULL;
DeleteCriticalSection(&(transport->ReadLock));
DeleteCriticalSection(&(transport->WriteLock));
free(transport);
}