libfreerdp/core/gateway/rpc.c

/*
 * FreeRDP: A Remote Desktop Protocol Implementation
 * RPC over HTTP
 *
 * Copyright 2012 Fujitsu Technology Solutions GmbH
 * Copyright 2012 Dmitrij Jasnov <dmitrij.jasnov@ts.fujitsu.com>
 * Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
 *
 * 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.
 */
 
#include <freerdp/config.h>
 
#include "../settings.h"
 
#include <winpr/crt.h>
#include <winpr/assert.h>
#include <winpr/tchar.h>
#include <winpr/synch.h>
#include <winpr/dsparse.h>
#include <winpr/crypto.h>
 
#include <freerdp/log.h>
 
#ifdef FREERDP_HAVE_VALGRIND_MEMCHECK_H
#include <valgrind/memcheck.h>
#endif
 
#include "../proxy.h"
#include "http.h"
#include "../credssp_auth.h"
#include "ncacn_http.h"
#include "rpc_bind.h"
#include "rpc_fault.h"
#include "rpc_client.h"
 
#include "rpc.h"
#include "rts.h"
 
#define TAG FREERDP_TAG("core.gateway.rpc")
 
static const char* PTYPE_STRINGS[] = { "PTYPE_REQUEST",       "PTYPE_PING",
                                     "PTYPE_RESPONSE",      "PTYPE_FAULT",
                                     "PTYPE_WORKING",       "PTYPE_NOCALL",
                                     "PTYPE_REJECT",        "PTYPE_ACK",
                                     "PTYPE_CL_CANCEL",     "PTYPE_FACK",
                                     "PTYPE_CANCEL_ACK",    "PTYPE_BIND",
                                     "PTYPE_BIND_ACK",      "PTYPE_BIND_NAK",
                                     "PTYPE_ALTER_CONTEXT", "PTYPE_ALTER_CONTEXT_RESP",
                                     "PTYPE_RPC_AUTH_3",    "PTYPE_SHUTDOWN",
                                     "PTYPE_CO_CANCEL",     "PTYPE_ORPHANED",
                                     "PTYPE_RTS",           "" };
 
static const char* client_in_state_str(CLIENT_IN_CHANNEL_STATE state)
{
  // NOLINTNEXTLINE(clang-analyzer-deadcode.DeadStores)
  const char* str = "CLIENT_IN_CHANNEL_STATE_UNKNOWN";
 
  switch (state)
  {
    case CLIENT_IN_CHANNEL_STATE_INITIAL:
      str = "CLIENT_IN_CHANNEL_STATE_INITIAL";
      break;
 
    case CLIENT_IN_CHANNEL_STATE_CONNECTED:
      str = "CLIENT_IN_CHANNEL_STATE_CONNECTED";
      break;
 
    case CLIENT_IN_CHANNEL_STATE_SECURITY:
      str = "CLIENT_IN_CHANNEL_STATE_SECURITY";
      break;
 
    case CLIENT_IN_CHANNEL_STATE_NEGOTIATED:
      str = "CLIENT_IN_CHANNEL_STATE_NEGOTIATED";
      break;
 
    case CLIENT_IN_CHANNEL_STATE_OPENED:
      str = "CLIENT_IN_CHANNEL_STATE_OPENED";
      break;
 
    case CLIENT_IN_CHANNEL_STATE_OPENED_A4W:
      str = "CLIENT_IN_CHANNEL_STATE_OPENED_A4W";
      break;
 
    case CLIENT_IN_CHANNEL_STATE_FINAL:
      str = "CLIENT_IN_CHANNEL_STATE_FINAL";
      break;
    default:
      break;
  }
  return str;
}
 
static const char* client_out_state_str(CLIENT_OUT_CHANNEL_STATE state)
{
  // NOLINTNEXTLINE(clang-analyzer-deadcode.DeadStores)
  const char* str = "CLIENT_OUT_CHANNEL_STATE_UNKNOWN";
 
  switch (state)
  {
    case CLIENT_OUT_CHANNEL_STATE_INITIAL:
      str = "CLIENT_OUT_CHANNEL_STATE_INITIAL";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_CONNECTED:
      str = "CLIENT_OUT_CHANNEL_STATE_CONNECTED";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_SECURITY:
      str = "CLIENT_OUT_CHANNEL_STATE_SECURITY";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_NEGOTIATED:
      str = "CLIENT_OUT_CHANNEL_STATE_NEGOTIATED";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_OPENED:
      str = "CLIENT_OUT_CHANNEL_STATE_OPENED";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_OPENED_A6W:
      str = "CLIENT_OUT_CHANNEL_STATE_OPENED_A6W";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_OPENED_A10W:
      str = "CLIENT_OUT_CHANNEL_STATE_OPENED_A10W";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_OPENED_B3W:
      str = "CLIENT_OUT_CHANNEL_STATE_OPENED_B3W";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_RECYCLED:
      str = "CLIENT_OUT_CHANNEL_STATE_RECYCLED";
      break;
 
    case CLIENT_OUT_CHANNEL_STATE_FINAL:
      str = "CLIENT_OUT_CHANNEL_STATE_FINAL";
      break;
    default:
      break;
  }
  return str;
}
 
const char* rpc_vc_state_str(VIRTUAL_CONNECTION_STATE state)
{
  // NOLINTNEXTLINE(clang-analyzer-deadcode.DeadStores)
  const char* str = "VIRTUAL_CONNECTION_STATE_UNKNOWN";
 
  switch (state)
  {
    case VIRTUAL_CONNECTION_STATE_INITIAL:
      str = "VIRTUAL_CONNECTION_STATE_INITIAL";
      break;
 
    case VIRTUAL_CONNECTION_STATE_OUT_CHANNEL_WAIT:
      str = "VIRTUAL_CONNECTION_STATE_OUT_CHANNEL_WAIT";
      break;
 
    case VIRTUAL_CONNECTION_STATE_WAIT_A3W:
      str = "VIRTUAL_CONNECTION_STATE_WAIT_A3W";
      break;
 
    case VIRTUAL_CONNECTION_STATE_WAIT_C2:
      str = "VIRTUAL_CONNECTION_STATE_WAIT_C2";
      break;
 
    case VIRTUAL_CONNECTION_STATE_OPENED:
      str = "VIRTUAL_CONNECTION_STATE_OPENED";
      break;
 
    case VIRTUAL_CONNECTION_STATE_FINAL:
      str = "VIRTUAL_CONNECTION_STATE_FINAL";
      break;
    default:
      break;
  }
  return str;
}
 
/*
 * [MS-RPCH]: Remote Procedure Call over HTTP Protocol Specification:
 * http://msdn.microsoft.com/en-us/library/cc243950/
 *
 *
 *
 *                                      Connection Establishment
 *
 *     Client                  Outbound Proxy           Inbound Proxy                 Server
 *        |                         |                         |                         |
 *        |-----------------IN Channel Request--------------->|                         |
 *        |---OUT Channel Request-->|                         |<-Legacy Server Response-|
 *        |                         |<--------------Legacy Server Response--------------|
 *        |                         |                         |                         |
 *        |---------CONN_A1-------->|                         |                         |
 *        |----------------------CONN_B1--------------------->|                         |
 *        |                         |----------------------CONN_A2--------------------->|
 *        |                         |                         |                         |
 *        |<--OUT Channel Response--|                         |---------CONN_B2-------->|
 *        |<--------CONN_A3---------|                         |                         |
 *        |                         |<---------------------CONN_C1----------------------|
 *        |                         |                         |<--------CONN_B3---------|
 *        |<--------CONN_C2---------|                         |                         |
 *        |                         |                         |                         |
 *
 */
 
void rpc_pdu_header_print(wLog* log, const rpcconn_hdr_t* header)
{
  WINPR_ASSERT(header);
 
  WLog_Print(log, WLOG_INFO, "rpc_vers: %" PRIu8 "", header->common.rpc_vers);
  WLog_Print(log, WLOG_INFO, "rpc_vers_minor: %" PRIu8 "", header->common.rpc_vers_minor);
 
  if (header->common.ptype > PTYPE_RTS)
    WLog_Print(log, WLOG_INFO, "ptype: %s (%" PRIu8 ")", "PTYPE_UNKNOWN", header->common.ptype);
  else
    WLog_Print(log, WLOG_INFO, "ptype: %s (%" PRIu8 ")", PTYPE_STRINGS[header->common.ptype],
               header->common.ptype);
 
  WLog_Print(log, WLOG_INFO, "pfc_flags (0x%02" PRIX8 ") = {", header->common.pfc_flags);
 
  if (header->common.pfc_flags & PFC_FIRST_FRAG)
    WLog_Print(log, WLOG_INFO, " PFC_FIRST_FRAG");
 
  if (header->common.pfc_flags & PFC_LAST_FRAG)
    WLog_Print(log, WLOG_INFO, " PFC_LAST_FRAG");
 
  if (header->common.pfc_flags & PFC_PENDING_CANCEL)
    WLog_Print(log, WLOG_INFO, " PFC_PENDING_CANCEL");
 
  if (header->common.pfc_flags & PFC_RESERVED_1)
    WLog_Print(log, WLOG_INFO, " PFC_RESERVED_1");
 
  if (header->common.pfc_flags & PFC_CONC_MPX)
    WLog_Print(log, WLOG_INFO, " PFC_CONC_MPX");
 
  if (header->common.pfc_flags & PFC_DID_NOT_EXECUTE)
    WLog_Print(log, WLOG_INFO, " PFC_DID_NOT_EXECUTE");
 
  if (header->common.pfc_flags & PFC_OBJECT_UUID)
    WLog_Print(log, WLOG_INFO, " PFC_OBJECT_UUID");
 
  WLog_Print(log, WLOG_INFO, " }");
  WLog_Print(log, WLOG_INFO,
             "packed_drep[4]: %02" PRIX8 " %02" PRIX8 " %02" PRIX8 " %02" PRIX8 "",
             header->common.packed_drep[0], header->common.packed_drep[1],
             header->common.packed_drep[2], header->common.packed_drep[3]);
  WLog_Print(log, WLOG_INFO, "frag_length: %" PRIu16 "", header->common.frag_length);
  WLog_Print(log, WLOG_INFO, "auth_length: %" PRIu16 "", header->common.auth_length);
  WLog_Print(log, WLOG_INFO, "call_id: %" PRIu32 "", header->common.call_id);
 
  if (header->common.ptype == PTYPE_RESPONSE)
  {
    WLog_Print(log, WLOG_INFO, "alloc_hint: %" PRIu32 "", header->response.alloc_hint);
    WLog_Print(log, WLOG_INFO, "p_cont_id: %" PRIu16 "", header->response.p_cont_id);
    WLog_Print(log, WLOG_INFO, "cancel_count: %" PRIu8 "", header->response.cancel_count);
    WLog_Print(log, WLOG_INFO, "reserved: %" PRIu8 "", header->response.reserved);
  }
}
 
rpcconn_common_hdr_t rpc_pdu_header_init(const rdpRpc* rpc)
{
  rpcconn_common_hdr_t header = { 0 };
  WINPR_ASSERT(rpc);
 
  header.rpc_vers = rpc->rpc_vers;
  header.rpc_vers_minor = rpc->rpc_vers_minor;
  header.packed_drep[0] = rpc->packed_drep[0];
  header.packed_drep[1] = rpc->packed_drep[1];
  header.packed_drep[2] = rpc->packed_drep[2];
  header.packed_drep[3] = rpc->packed_drep[3];
  return header;
}
 
size_t rpc_offset_align(size_t* offset, size_t alignment)
{
  size_t pad = 0;
  pad = *offset;
  *offset = (*offset + alignment - 1) & ~(alignment - 1);
  pad = *offset - pad;
  return pad;
}
 
size_t rpc_offset_pad(size_t* offset, size_t pad)
{
  *offset += pad;
  return pad;
}
 
/*
 * PDU Segments:
 *  ________________________________
 * |                                |
 * |           PDU Header           |
 * |________________________________|
 * |                                |
 * |                                |
 * |            PDU Body            |
 * |                                |
 * |________________________________|
 * |                                |
 * |        Security Trailer        |
 * |________________________________|
 * |                                |
 * |      Authentication Token      |
 * |________________________________|
 */
 
/*
 * PDU Structure with verification trailer
 *
 * MUST only appear in a request PDU!
 *  ________________________________
 * |                                |
 * |           PDU Header           |
 * |________________________________| _______
 * |                                |   /|\
 * |                                |    |
 * |           Stub Data            |    |
 * |                                |    |
 * |________________________________|    |
 * |                                | PDU Body
 * |            Stub Pad            |    |
 * |________________________________|    |
 * |                                |    |
 * |      Verification Trailer      |    |
 * |________________________________|    |
 * |                                |    |
 * |       Authentication Pad       |    |
 * |________________________________| __\|/__
 * |                                |
 * |        Security Trailer        |
 * |________________________________|
 * |                                |
 * |      Authentication Token      |
 * |________________________________|
 *
 */
 
/*
 * Security Trailer:
 *
 * The sec_trailer structure MUST be placed at the end of the PDU, including past stub data,
 * when present. The sec_trailer structure MUST be 4-byte aligned with respect to the beginning
 * of the PDU. Padding octets MUST be used to align the sec_trailer structure if its natural
 * beginning is not already 4-byte aligned.
 *
 * All PDUs that carry sec_trailer information share certain common fields:
 * frag_length and auth_length. The beginning of the sec_trailer structure for each PDU MUST be
 * calculated to start from offset (frag_length – auth_length – 8) from the beginning of the PDU.
 *
 * Immediately after the sec_trailer structure, there MUST be a BLOB carrying the authentication
 * information produced by the security provider. This BLOB is called the authentication token and
 * MUST be of size auth_length. The size MUST also be equal to the length from the first octet
 * immediately after the sec_trailer structure all the way to the end of the fragment;
 * the two values MUST be the same.
 *
 * A client or a server that (during composing of a PDU) has allocated more space for the
 * authentication token than the security provider fills in SHOULD fill in the rest of
 * the allocated space with zero octets. These zero octets are still considered to belong
 * to the authentication token part of the PDU.
 *
 */
 
BOOL rpc_get_stub_data_info(rdpRpc* rpc, const rpcconn_hdr_t* header, size_t* poffset,
                            size_t* length)
{
  size_t used = 0;
  size_t offset = 0;
  BOOL rc = FALSE;
  UINT32 frag_length = 0;
  UINT32 auth_length = 0;
  UINT32 auth_pad_length = 0;
  UINT32 sec_trailer_offset = 0;
  const rpc_sec_trailer* sec_trailer = NULL;
 
  WINPR_ASSERT(rpc);
  WINPR_ASSERT(header);
  WINPR_ASSERT(poffset);
  WINPR_ASSERT(length);
 
  offset = RPC_COMMON_FIELDS_LENGTH;
 
  switch (header->common.ptype)
  {
    case PTYPE_RESPONSE:
      offset += 8;
      rpc_offset_align(&offset, 8);
      sec_trailer = &header->response.auth_verifier;
      break;
 
    case PTYPE_REQUEST:
      offset += 4;
      rpc_offset_align(&offset, 8);
      sec_trailer = &header->request.auth_verifier;
      break;
 
    case PTYPE_RTS:
      offset += 4;
      break;
 
    default:
      WLog_Print(rpc->log, WLOG_ERROR, "Unknown PTYPE: 0x%02" PRIX8 "", header->common.ptype);
      goto fail;
  }
 
  frag_length = header->common.frag_length;
  auth_length = header->common.auth_length;
 
  if (poffset)
    *poffset = offset;
 
  /* The fragment must be larger than the authentication trailer */
  used = offset + auth_length + 8ull;
  if (sec_trailer)
  {
    auth_pad_length = sec_trailer->auth_pad_length;
    used += sec_trailer->auth_pad_length;
  }
 
  if (frag_length < used)
    goto fail;
 
  if (!length)
    return TRUE;
 
  sec_trailer_offset = frag_length - auth_length - 8;
 
  /*
   * According to [MS-RPCE], auth_pad_length is the number of padding
   * octets used to 4-byte align the security trailer, but in practice
   * we get values up to 15, which indicates 16-byte alignment.
   */
 
  if ((frag_length - (sec_trailer_offset + 8)) != auth_length)
  {
    WLog_Print(rpc->log, WLOG_ERROR,
               "invalid auth_length: actual: %" PRIu32 ", expected: %" PRIu32 "", auth_length,
               (frag_length - (sec_trailer_offset + 8)));
  }
 
  *length = sec_trailer_offset - auth_pad_length - offset;
 
  rc = TRUE;
fail:
  return rc;
}
 
SSIZE_T rpc_channel_read(RpcChannel* channel, wStream* s, size_t length)
{
  int status = 0;
 
  if (!channel || (length > INT32_MAX))
    return -1;
 
  ERR_clear_error();
  status = BIO_read(channel->tls->bio, Stream_Pointer(s), (INT32)length);
 
  if (status > 0)
  {
    Stream_Seek(s, (size_t)status);
    return status;
  }
 
  if (BIO_should_retry(channel->tls->bio))
    return 0;
 
  WLog_Print(channel->rpc->log, WLOG_ERROR, "rpc_channel_read: Out of retries");
  return -1;
}
 
SSIZE_T rpc_channel_write(RpcChannel* channel, const BYTE* data, size_t length)
{
  if (!channel)
    return -1;
 
  return freerdp_tls_write_all(channel->tls, data, length);
}
 
BOOL rpc_in_channel_transition_to_state(RpcInChannel* inChannel, CLIENT_IN_CHANNEL_STATE state)
{
  if (!inChannel)
    return FALSE;
 
  inChannel->State = state;
  WLog_Print(inChannel->common.rpc->log, WLOG_DEBUG, "%s", client_in_state_str(state));
  return TRUE;
}
 
static int rpc_channel_rpch_init(RpcClient* client, RpcChannel* channel, const char* inout,
                                 const GUID* guid)
{
  HttpContext* http = NULL;
  rdpSettings* settings = NULL;
  UINT32 timeout = 0;
 
  if (!client || !channel || !inout || !client->context || !client->context->settings)
    return -1;
 
  settings = client->context->settings;
  channel->auth = credssp_auth_new(client->context);
  rts_generate_cookie((BYTE*)&channel->Cookie);
  channel->client = client;
 
  if (!channel->auth)
    return -1;
 
  channel->http = http_context_new();
 
  if (!channel->http)
    return -1;
 
  http = channel->http;
 
  {
    if (!http_context_set_pragma(http, "ResourceTypeUuid=44e265dd-7daf-42cd-8560-3cdb6e7a2729"))
      return -1;
 
    if (guid)
    {
      char* strguid = NULL;
      RPC_STATUS rpcStatus = UuidToStringA(guid, &strguid);
 
      if (rpcStatus != RPC_S_OK)
        return -1;
 
      const BOOL rc = http_context_append_pragma(http, "SessionId=%s", strguid);
      RpcStringFreeA(&strguid);
      if (!rc)
        return -1;
    }
    if (timeout)
    {
      if (!http_context_append_pragma(http, "MinConnTimeout=%" PRIu32, timeout))
        return -1;
    }
 
    if (!http_context_set_rdg_correlation_id(http, guid) ||
        !http_context_set_rdg_connection_id(http, guid))
      return -1;
  }
 
  /* TODO: "/rpcwithcert/rpcproxy.dll". */
  if (!http_context_set_method(http, inout) ||
      !http_context_set_uri(http, "/rpc/rpcproxy.dll?localhost:3388") ||
      !http_context_set_accept(http, "application/rpc") ||
      !http_context_set_cache_control(http, "no-cache") ||
      !http_context_set_connection(http, "Keep-Alive") ||
      !http_context_set_user_agent(http, "MSRPC") ||
      !http_context_set_host(http, settings->GatewayHostname))
    return -1;
 
  return 1;
}
 
static int rpc_in_channel_init(rdpRpc* rpc, RpcInChannel* inChannel, const GUID* guid)
{
  WINPR_ASSERT(rpc);
  WINPR_ASSERT(inChannel);
 
  inChannel->common.rpc = rpc;
  inChannel->State = CLIENT_IN_CHANNEL_STATE_INITIAL;
  inChannel->BytesSent = 0;
  inChannel->SenderAvailableWindow = rpc->ReceiveWindow;
  inChannel->PingOriginator.ConnectionTimeout = 30;
  inChannel->PingOriginator.KeepAliveInterval = 0;
 
  if (rpc_channel_rpch_init(rpc->client, &inChannel->common, "RPC_IN_DATA", guid) < 0)
    return -1;
 
  return 1;
}
 
static RpcInChannel* rpc_in_channel_new(rdpRpc* rpc, const GUID* guid)
{
  RpcInChannel* inChannel = (RpcInChannel*)calloc(1, sizeof(RpcInChannel));
 
  if (inChannel)
  {
    rpc_in_channel_init(rpc, inChannel, guid);
  }
 
  return inChannel;
}
 
void rpc_channel_free(RpcChannel* channel)
{
  if (!channel)
    return;
 
  credssp_auth_free(channel->auth);
  http_context_free(channel->http);
  freerdp_tls_free(channel->tls);
  free(channel);
}
 
BOOL rpc_out_channel_transition_to_state(RpcOutChannel* outChannel, CLIENT_OUT_CHANNEL_STATE state)
{
  if (!outChannel)
    return FALSE;
 
  outChannel->State = state;
  WLog_Print(outChannel->common.rpc->log, WLOG_DEBUG, "%s", client_out_state_str(state));
  return TRUE;
}
 
static int rpc_out_channel_init(rdpRpc* rpc, RpcOutChannel* outChannel, const GUID* guid)
{
  WINPR_ASSERT(rpc);
  WINPR_ASSERT(outChannel);
 
  outChannel->common.rpc = rpc;
  outChannel->State = CLIENT_OUT_CHANNEL_STATE_INITIAL;
  outChannel->BytesReceived = 0;
  outChannel->ReceiverAvailableWindow = rpc->ReceiveWindow;
  outChannel->ReceiveWindow = rpc->ReceiveWindow;
  outChannel->ReceiveWindowSize = rpc->ReceiveWindow;
  outChannel->AvailableWindowAdvertised = rpc->ReceiveWindow;
 
  if (rpc_channel_rpch_init(rpc->client, &outChannel->common, "RPC_OUT_DATA", guid) < 0)
    return -1;
 
  return 1;
}
 
RpcOutChannel* rpc_out_channel_new(rdpRpc* rpc, const GUID* guid)
{
  RpcOutChannel* outChannel = (RpcOutChannel*)calloc(1, sizeof(RpcOutChannel));
 
  if (outChannel)
  {
    rpc_out_channel_init(rpc, outChannel, guid);
  }
 
  return outChannel;
}
 
BOOL rpc_virtual_connection_transition_to_state(rdpRpc* rpc, RpcVirtualConnection* connection,
                                                VIRTUAL_CONNECTION_STATE state)
{
  if (!connection)
    return FALSE;
 
  WINPR_ASSERT(rpc);
  connection->State = state;
  WLog_Print(rpc->log, WLOG_DEBUG, "%s", rpc_vc_state_str(state));
  return TRUE;
}
 
static void rpc_virtual_connection_free(RpcVirtualConnection* connection)
{
  if (!connection)
    return;
 
  if (connection->DefaultInChannel)
    rpc_channel_free(&connection->DefaultInChannel->common);
  if (connection->NonDefaultInChannel)
    rpc_channel_free(&connection->NonDefaultInChannel->common);
  if (connection->DefaultOutChannel)
    rpc_channel_free(&connection->DefaultOutChannel->common);
  if (connection->NonDefaultOutChannel)
    rpc_channel_free(&connection->NonDefaultOutChannel->common);
  free(connection);
}
 
static RpcVirtualConnection* rpc_virtual_connection_new(rdpRpc* rpc)
{
  WINPR_ASSERT(rpc);
 
  RpcVirtualConnection* connection =
      (RpcVirtualConnection*)calloc(1, sizeof(RpcVirtualConnection));
 
  if (!connection)
    return NULL;
 
  rts_generate_cookie((BYTE*)&(connection->Cookie));
  rts_generate_cookie((BYTE*)&(connection->AssociationGroupId));
  connection->State = VIRTUAL_CONNECTION_STATE_INITIAL;
 
  connection->DefaultInChannel = rpc_in_channel_new(rpc, &connection->Cookie);
 
  if (!connection->DefaultInChannel)
    goto fail;
 
  connection->DefaultOutChannel = rpc_out_channel_new(rpc, &connection->Cookie);
 
  if (!connection->DefaultOutChannel)
    goto fail;
 
  return connection;
fail:
  rpc_virtual_connection_free(connection);
  return NULL;
}
 
static BOOL rpc_channel_tls_connect(RpcChannel* channel, UINT32 timeout)
{
  if (!channel || !channel->client || !channel->client->context ||
      !channel->client->context->settings)
    return FALSE;
 
  rdpContext* context = channel->client->context;
  WINPR_ASSERT(context);
 
  rdpSettings* settings = context->settings;
  WINPR_ASSERT(settings);
 
  const char* proxyUsername = freerdp_settings_get_string(settings, FreeRDP_ProxyUsername);
  const char* proxyPassword = freerdp_settings_get_string(settings, FreeRDP_ProxyPassword);
 
  rdpTransport* transport = freerdp_get_transport(context);
  rdpTransportLayer* layer =
      transport_connect_layer(transport, channel->client->host, channel->client->port, timeout);
 
  if (!layer)
    return FALSE;
 
  BIO* layerBio = BIO_new(BIO_s_transport_layer());
  if (!layerBio)
  {
    transport_layer_free(layer);
    return FALSE;
  }
  BIO_set_data(layerBio, layer);
 
  BIO* bufferedBio = BIO_new(BIO_s_buffered_socket());
  if (!bufferedBio)
  {
    BIO_free_all(layerBio);
    return FALSE;
  }
 
  bufferedBio = BIO_push(bufferedBio, layerBio);
 
  if (!BIO_set_nonblock(bufferedBio, TRUE))
  {
    BIO_free_all(bufferedBio);
    return FALSE;
  }
 
  if (channel->client->isProxy)
  {
    if (!proxy_connect(context, bufferedBio, proxyUsername, proxyPassword,
                       settings->GatewayHostname, settings->GatewayPort))
    {
      BIO_free_all(bufferedBio);
      return FALSE;
    }
  }
 
  channel->bio = bufferedBio;
  rdpTls* tls = channel->tls = freerdp_tls_new(context);
 
  if (!tls)
    return FALSE;
 
  tls->hostname = settings->GatewayHostname;
  tls->port = MIN(UINT16_MAX, settings->GatewayPort);
  tls->isGatewayTransport = TRUE;
  int tlsStatus = freerdp_tls_connect(tls, bufferedBio);
 
  if (tlsStatus < 1)
  {
    if (tlsStatus < 0)
    {
      freerdp_set_last_error_if_not(context, FREERDP_ERROR_TLS_CONNECT_FAILED);
    }
    else
    {
      freerdp_set_last_error_if_not(context, FREERDP_ERROR_CONNECT_CANCELLED);
    }
 
    return FALSE;
  }
 
  return TRUE;
}
 
static int rpc_in_channel_connect(RpcInChannel* inChannel, UINT32 timeout)
{
  rdpContext* context = NULL;
 
  if (!inChannel || !inChannel->common.client || !inChannel->common.client->context)
    return -1;
 
  context = inChannel->common.client->context;
 
  /* Connect IN Channel */
 
  if (!rpc_channel_tls_connect(&inChannel->common, timeout))
    return -1;
 
  rpc_in_channel_transition_to_state(inChannel, CLIENT_IN_CHANNEL_STATE_CONNECTED);
 
  if (!rpc_ncacn_http_auth_init(context, &inChannel->common))
    return -1;
 
  /* Send IN Channel Request */
 
  if (!rpc_ncacn_http_send_in_channel_request(&inChannel->common))
  {
    WLog_Print(inChannel->common.rpc->log, WLOG_ERROR,
               "rpc_ncacn_http_send_in_channel_request failure");
    return -1;
  }
 
  if (!rpc_in_channel_transition_to_state(inChannel, CLIENT_IN_CHANNEL_STATE_SECURITY))
    return -1;
 
  return 1;
}
 
static int rpc_out_channel_connect(RpcOutChannel* outChannel, int timeout)
{
  rdpContext* context = NULL;
 
  if (!outChannel || !outChannel->common.client || !outChannel->common.client->context)
    return -1;
 
  context = outChannel->common.client->context;
 
  /* Connect OUT Channel */
 
  if (!rpc_channel_tls_connect(&outChannel->common, timeout))
    return -1;
 
  rpc_out_channel_transition_to_state(outChannel, CLIENT_OUT_CHANNEL_STATE_CONNECTED);
 
  if (!rpc_ncacn_http_auth_init(context, &outChannel->common))
    return FALSE;
 
  /* Send OUT Channel Request */
 
  if (!rpc_ncacn_http_send_out_channel_request(&outChannel->common, FALSE))
  {
    WLog_Print(outChannel->common.rpc->log, WLOG_ERROR,
               "rpc_ncacn_http_send_out_channel_request failure");
    return FALSE;
  }
 
  rpc_out_channel_transition_to_state(outChannel, CLIENT_OUT_CHANNEL_STATE_SECURITY);
  return 1;
}
 
int rpc_out_channel_replacement_connect(RpcOutChannel* outChannel, int timeout)
{
  rdpContext* context = NULL;
 
  if (!outChannel || !outChannel->common.client || !outChannel->common.client->context)
    return -1;
 
  context = outChannel->common.client->context;
 
  /* Connect OUT Channel */
 
  if (!rpc_channel_tls_connect(&outChannel->common, timeout))
    return -1;
 
  rpc_out_channel_transition_to_state(outChannel, CLIENT_OUT_CHANNEL_STATE_CONNECTED);
 
  if (!rpc_ncacn_http_auth_init(context, (RpcChannel*)outChannel))
    return FALSE;
 
  /* Send OUT Channel Request */
 
  if (!rpc_ncacn_http_send_out_channel_request(&outChannel->common, TRUE))
  {
    WLog_Print(outChannel->common.rpc->log, WLOG_ERROR,
               "rpc_ncacn_http_send_out_channel_request failure");
    return FALSE;
  }
 
  rpc_out_channel_transition_to_state(outChannel, CLIENT_OUT_CHANNEL_STATE_SECURITY);
  return 1;
}
 
BOOL rpc_connect(rdpRpc* rpc, UINT32 timeout)
{
  RpcInChannel* inChannel = NULL;
  RpcOutChannel* outChannel = NULL;
  RpcVirtualConnection* connection = NULL;
  rpc->VirtualConnection = rpc_virtual_connection_new(rpc);
 
  if (!rpc->VirtualConnection)
    return FALSE;
 
  connection = rpc->VirtualConnection;
  inChannel = connection->DefaultInChannel;
  outChannel = connection->DefaultOutChannel;
  rpc_virtual_connection_transition_to_state(rpc, connection, VIRTUAL_CONNECTION_STATE_INITIAL);
 
  if (rpc_in_channel_connect(inChannel, timeout) < 0)
    return FALSE;
 
  if (rpc_out_channel_connect(outChannel, timeout) < 0)
    return FALSE;
 
  return TRUE;
}
 
rdpRpc* rpc_new(rdpTransport* transport)
{
  rdpContext* context = transport_get_context(transport);
  rdpRpc* rpc = NULL;
 
  WINPR_ASSERT(context);
 
  rpc = (rdpRpc*)calloc(1, sizeof(rdpRpc));
 
  if (!rpc)
    return NULL;
 
  rpc->log = WLog_Get(TAG);
  rpc->State = RPC_CLIENT_STATE_INITIAL;
  rpc->transport = transport;
  rpc->SendSeqNum = 0;
  rpc->auth = credssp_auth_new(context);
 
  if (!rpc->auth)
    goto out_free;
 
  rpc->PipeCallId = 0;
  rpc->StubCallId = 0;
  rpc->StubFragCount = 0;
  rpc->rpc_vers = 5;
  rpc->rpc_vers_minor = 0;
  /* little-endian data representation */
  rpc->packed_drep[0] = 0x10;
  rpc->packed_drep[1] = 0x00;
  rpc->packed_drep[2] = 0x00;
  rpc->packed_drep[3] = 0x00;
  rpc->max_xmit_frag = 0x0FF8;
  rpc->max_recv_frag = 0x0FF8;
  rpc->ReceiveWindow = 0x00010000;
  rpc->ChannelLifetime = 0x40000000;
  rpc->KeepAliveInterval = 300000;
  rpc->CurrentKeepAliveInterval = rpc->KeepAliveInterval;
  rpc->CurrentKeepAliveTime = 0;
  rpc->CallId = 2;
  rpc->client = rpc_client_new(context, rpc->max_recv_frag);
 
  if (!rpc->client)
    goto out_free;
 
  return rpc;
out_free:
  WINPR_PRAGMA_DIAG_PUSH
  WINPR_PRAGMA_DIAG_IGNORED_MISMATCHED_DEALLOC
  rpc_free(rpc);
  WINPR_PRAGMA_DIAG_POP
  return NULL;
}
 
void rpc_free(rdpRpc* rpc)
{
  if (rpc)
  {
    rpc_client_free(rpc->client);
    credssp_auth_free(rpc->auth);
    rpc_virtual_connection_free(rpc->VirtualConnection);
    free(rpc);
  }
}