rdg.c

 
#include <stdint.h>
 
#include <freerdp/config.h>
 
#include "../settings.h"
 
#include <winpr/assert.h>
#include <winpr/cast.h>
 
#include <winpr/crt.h>
#include <winpr/synch.h>
#include <winpr/print.h>
#include <winpr/stream.h>
#include <winpr/winsock.h>
#include <winpr/cred.h>
 
#include <freerdp/log.h>
#include <freerdp/error.h>
#include <freerdp/utils/ringbuffer.h>
#include <freerdp/utils/smartcardlogon.h>
 
#include "rdg.h"
#include "websocket.h"
#include "../credssp_auth.h"
#include "../proxy.h"
#include "../rdp.h"
#include "../../crypto/opensslcompat.h"
#include "rpc_fault.h"
#include "../utils.h"
 
#define TAG FREERDP_TAG("core.gateway.rdg")
 
#define AUTH_PKG NEGO_SSP_NAME
 
/* HTTP channel response fields present flags. */
#define HTTP_CHANNEL_RESPONSE_FIELD_CHANNELID 0x1
#define HTTP_CHANNEL_RESPONSE_OPTIONAL 0x2
#define HTTP_CHANNEL_RESPONSE_FIELD_UDPPORT 0x4
 
/* HTTP extended auth. */
#define HTTP_EXTENDED_AUTH_NONE 0x0
#define HTTP_EXTENDED_AUTH_SC 0x1         /* Smart card authentication. */
#define HTTP_EXTENDED_AUTH_PAA 0x02       /* Pluggable authentication. */
#define HTTP_EXTENDED_AUTH_SSPI_NTLM 0x04 /* NTLM extended authentication. */
#define HTTP_EXTENDED_AUTH_BEARER 0x08    /* HTTP Bearer authentication. */
 
/* HTTP packet types. */
#define PKT_TYPE_HANDSHAKE_REQUEST 0x1
#define PKT_TYPE_HANDSHAKE_RESPONSE 0x2
#define PKT_TYPE_EXTENDED_AUTH_MSG 0x3
#define PKT_TYPE_TUNNEL_CREATE 0x4
#define PKT_TYPE_TUNNEL_RESPONSE 0x5
#define PKT_TYPE_TUNNEL_AUTH 0x6
#define PKT_TYPE_TUNNEL_AUTH_RESPONSE 0x7
#define PKT_TYPE_CHANNEL_CREATE 0x8
#define PKT_TYPE_CHANNEL_RESPONSE 0x9
#define PKT_TYPE_DATA 0xA
#define PKT_TYPE_SERVICE_MESSAGE 0xB
#define PKT_TYPE_REAUTH_MESSAGE 0xC
#define PKT_TYPE_KEEPALIVE 0xD
#define PKT_TYPE_CLOSE_CHANNEL 0x10
#define PKT_TYPE_CLOSE_CHANNEL_RESPONSE 0x11
 
/* HTTP tunnel auth fields present flags. */
// #define HTTP_TUNNEL_AUTH_FIELD_SOH 0x1
 
/* HTTP tunnel auth response fields present flags. */
#define HTTP_TUNNEL_AUTH_RESPONSE_FIELD_REDIR_FLAGS 0x1
#define HTTP_TUNNEL_AUTH_RESPONSE_FIELD_IDLE_TIMEOUT 0x2
#define HTTP_TUNNEL_AUTH_RESPONSE_FIELD_SOH_RESPONSE 0x4
 
/* HTTP tunnel packet fields present flags. */
#define HTTP_TUNNEL_PACKET_FIELD_PAA_COOKIE 0x1
// #define HTTP_TUNNEL_PACKET_FIELD_REAUTH 0x2
 
/* HTTP tunnel response fields present flags. */
#define HTTP_TUNNEL_RESPONSE_FIELD_TUNNEL_ID 0x1
#define HTTP_TUNNEL_RESPONSE_FIELD_CAPS 0x2
#define HTTP_TUNNEL_RESPONSE_FIELD_SOH_REQ 0x4
#define HTTP_TUNNEL_RESPONSE_FIELD_CONSENT_MSG 0x10
 
/* HTTP capability type enumeration. */
#define HTTP_CAPABILITY_TYPE_QUAR_SOH 0x1
#define HTTP_CAPABILITY_IDLE_TIMEOUT 0x2
#define HTTP_CAPABILITY_MESSAGING_CONSENT_SIGN 0x4
#define HTTP_CAPABILITY_MESSAGING_SERVICE_MSG 0x8
#define HTTP_CAPABILITY_REAUTH 0x10
#define HTTP_CAPABILITY_UDP_TRANSPORT 0x20
 
typedef struct
{
  TRANSFER_ENCODING httpTransferEncoding;
  BOOL isWebsocketTransport;
  union context
  {
    http_encoding_chunked_context chunked;
    websocket_context* websocket;
  } context;
} rdg_http_encoding_context;
 
struct rdp_rdg
{
  rdpContext* context;
  BOOL attached;
  BIO* frontBio;
  rdpTls* tlsIn;
  rdpTls* tlsOut;
  rdpCredsspAuth* auth;
  HttpContext* http;
  CRITICAL_SECTION writeSection;
 
  UUID guid;
 
  int state;
  UINT16 packetRemainingCount;
  UINT16 reserved1;
  int timeout;
  UINT16 extAuth;
  UINT16 reserved2;
  rdg_http_encoding_context transferEncoding;
 
  SmartcardCertInfo* smartcard;
  wLog* log;
};
 
enum
{
  RDG_CLIENT_STATE_INITIAL,
  RDG_CLIENT_STATE_HANDSHAKE,
  RDG_CLIENT_STATE_TUNNEL_CREATE,
  RDG_CLIENT_STATE_TUNNEL_AUTHORIZE,
  RDG_CLIENT_STATE_CHANNEL_CREATE,
  RDG_CLIENT_STATE_OPENED,
};
 
#pragma pack(push, 1)
 
typedef struct rdg_packet_header
{
  UINT16 type;
  UINT16 reserved;
  UINT32 packetLength;
} RdgPacketHeader;
 
#pragma pack(pop)
 
typedef struct
{
  UINT32 code;
  const char* name;
} t_flag_mapping;
 
static const t_flag_mapping tunnel_response_fields_present[] = {
  { HTTP_TUNNEL_RESPONSE_FIELD_TUNNEL_ID, "HTTP_TUNNEL_RESPONSE_FIELD_TUNNEL_ID" },
  { HTTP_TUNNEL_RESPONSE_FIELD_CAPS, "HTTP_TUNNEL_RESPONSE_FIELD_CAPS" },
  { HTTP_TUNNEL_RESPONSE_FIELD_SOH_REQ, "HTTP_TUNNEL_RESPONSE_FIELD_SOH_REQ" },
  { HTTP_TUNNEL_RESPONSE_FIELD_CONSENT_MSG, "HTTP_TUNNEL_RESPONSE_FIELD_CONSENT_MSG" }
};
 
static const t_flag_mapping channel_response_fields_present[] = {
  { HTTP_CHANNEL_RESPONSE_FIELD_CHANNELID, "HTTP_CHANNEL_RESPONSE_FIELD_CHANNELID" },
  { HTTP_CHANNEL_RESPONSE_OPTIONAL, "HTTP_CHANNEL_RESPONSE_OPTIONAL" },
  { HTTP_CHANNEL_RESPONSE_FIELD_UDPPORT, "HTTP_CHANNEL_RESPONSE_FIELD_UDPPORT" }
};
 
static const t_flag_mapping tunnel_authorization_response_fields_present[] = {
  { HTTP_TUNNEL_AUTH_RESPONSE_FIELD_REDIR_FLAGS, "HTTP_TUNNEL_AUTH_RESPONSE_FIELD_REDIR_FLAGS" },
  { HTTP_TUNNEL_AUTH_RESPONSE_FIELD_IDLE_TIMEOUT,
    "HTTP_TUNNEL_AUTH_RESPONSE_FIELD_IDLE_TIMEOUT" },
  { HTTP_TUNNEL_AUTH_RESPONSE_FIELD_SOH_RESPONSE,
    "HTTP_TUNNEL_AUTH_RESPONSE_FIELD_SOH_RESPONSE" }
};
 
static const t_flag_mapping extended_auth[] = {
  { HTTP_EXTENDED_AUTH_NONE, "HTTP_EXTENDED_AUTH_NONE" },
  { HTTP_EXTENDED_AUTH_SC, "HTTP_EXTENDED_AUTH_SC" },
  { HTTP_EXTENDED_AUTH_PAA, "HTTP_EXTENDED_AUTH_PAA" },
  { HTTP_EXTENDED_AUTH_SSPI_NTLM, "HTTP_EXTENDED_AUTH_SSPI_NTLM" }
};
 
static const t_flag_mapping capabilities_enum[] = {
  { HTTP_CAPABILITY_TYPE_QUAR_SOH, "HTTP_CAPABILITY_TYPE_QUAR_SOH" },
  { HTTP_CAPABILITY_IDLE_TIMEOUT, "HTTP_CAPABILITY_IDLE_TIMEOUT" },
  { HTTP_CAPABILITY_MESSAGING_CONSENT_SIGN, "HTTP_CAPABILITY_MESSAGING_CONSENT_SIGN" },
  { HTTP_CAPABILITY_MESSAGING_SERVICE_MSG, "HTTP_CAPABILITY_MESSAGING_SERVICE_MSG" },
  { HTTP_CAPABILITY_REAUTH, "HTTP_CAPABILITY_REAUTH" },
  { HTTP_CAPABILITY_UDP_TRANSPORT, "HTTP_CAPABILITY_UDP_TRANSPORT" }
};
 
static const char* flags_to_string(UINT32 flags, const t_flag_mapping* map, size_t elements)
{
  static char buffer[1024] = { 0 };
  char fields[12] = { 0 };
 
  for (size_t x = 0; x < elements; x++)
  {
    const t_flag_mapping* cur = &map[x];
 
    if ((cur->code & flags) != 0)
      winpr_str_append(cur->name, buffer, sizeof(buffer), "|");
  }
 
  (void)sprintf_s(fields, ARRAYSIZE(fields), " [%04" PRIx32 "]", flags);
  winpr_str_append(fields, buffer, sizeof(buffer), NULL);
  return buffer;
}
 
static const char* channel_response_fields_present_to_string(UINT16 fieldsPresent)
{
  return flags_to_string(fieldsPresent, channel_response_fields_present,
                         ARRAYSIZE(channel_response_fields_present));
}
 
static const char* tunnel_response_fields_present_to_string(UINT16 fieldsPresent)
{
  return flags_to_string(fieldsPresent, tunnel_response_fields_present,
                         ARRAYSIZE(tunnel_response_fields_present));
}
 
static const char* tunnel_authorization_response_fields_present_to_string(UINT16 fieldsPresent)
{
  return flags_to_string(fieldsPresent, tunnel_authorization_response_fields_present,
                         ARRAYSIZE(tunnel_authorization_response_fields_present));
}
 
static const char* extended_auth_to_string(UINT16 auth)
{
  if (auth == HTTP_EXTENDED_AUTH_NONE)
    return "HTTP_EXTENDED_AUTH_NONE [0x0000]";
 
  return flags_to_string(auth, extended_auth, ARRAYSIZE(extended_auth));
}
 
static const char* capabilities_enum_to_string(UINT32 capabilities)
{
  return flags_to_string(capabilities, capabilities_enum, ARRAYSIZE(capabilities_enum));
}
 
static BOOL rdg_read_http_unicode_string(wLog* log, wStream* s, const WCHAR** string,
                                         UINT16* lengthInBytes)
{
  UINT16 strLenBytes = 0;
  size_t rem = Stream_GetRemainingLength(s);
 
  /* Read length of the string */
  if (!Stream_CheckAndLogRequiredLengthWLog(log, s, 4))
  {
    WLog_Print(log, WLOG_ERROR, "Could not read stream length, only have %" PRIuz " bytes",
               rem);
    return FALSE;
  }
  Stream_Read_UINT16(s, strLenBytes);
 
  /* Remember position of our string */
  const WCHAR* str = Stream_ConstPointer(s);
 
  /* seek past the string - if this fails something is wrong */
  if (!Stream_SafeSeek(s, strLenBytes))
  {
    WLog_Print(log, WLOG_ERROR,
               "Could not read stream data, only have %" PRIuz " bytes, expected %" PRIu16,
               rem - 4, strLenBytes);
    return FALSE;
  }
 
  /* return the string data (if wanted) */
  if (string)
    *string = str;
  if (lengthInBytes)
    *lengthInBytes = strLenBytes;
 
  return TRUE;
}
 
static BOOL rdg_write_chunked(BIO* bio, wStream* sPacket)
{
  size_t len = 0;
  int status = 0;
  wStream* sChunk = NULL;
  char chunkSize[11];
  (void)sprintf_s(chunkSize, sizeof(chunkSize), "%" PRIXz "\r\n", Stream_Length(sPacket));
  sChunk = Stream_New(NULL, strnlen(chunkSize, sizeof(chunkSize)) + Stream_Length(sPacket) + 2);
 
  if (!sChunk)
    return FALSE;
 
  Stream_Write(sChunk, chunkSize, strnlen(chunkSize, sizeof(chunkSize)));
  Stream_Write(sChunk, Stream_Buffer(sPacket), Stream_Length(sPacket));
  Stream_Write(sChunk, "\r\n", 2);
  Stream_SealLength(sChunk);
  len = Stream_Length(sChunk);
 
  if (len > INT_MAX)
  {
    Stream_Free(sChunk, TRUE);
    return FALSE;
  }
 
  ERR_clear_error();
  status = BIO_write(bio, Stream_Buffer(sChunk), (int)len);
  Stream_Free(sChunk, TRUE);
 
  if (status != (SSIZE_T)len)
    return FALSE;
 
  return TRUE;
}
 
static BOOL rdg_write_packet(rdpRdg* rdg, wStream* sPacket)
{
  if (rdg->transferEncoding.isWebsocketTransport)
    return websocket_context_write_wstream(rdg->transferEncoding.context.websocket,
                                           rdg->tlsOut->bio, sPacket, WebsocketBinaryOpcode);
 
  return rdg_write_chunked(rdg->tlsIn->bio, sPacket);
}
 
static int rdg_socket_read(BIO* bio, BYTE* pBuffer, size_t size,
                           rdg_http_encoding_context* encodingContext)
{
  WINPR_ASSERT(encodingContext != NULL);
  if (size > INT32_MAX)
    return -1;
 
  if (encodingContext->isWebsocketTransport)
    return websocket_context_read(encodingContext->context.websocket, bio, pBuffer, size);
 
  switch (encodingContext->httpTransferEncoding)
  {
    case TransferEncodingIdentity:
      ERR_clear_error();
      return BIO_read(bio, pBuffer, (int)size);
    case TransferEncodingChunked:
      return http_chuncked_read(bio, pBuffer, size, &encodingContext->context.chunked);
    default:
      return -1;
  }
}
 
static BOOL rdg_shall_abort(rdpRdg* rdg)
{
  WINPR_ASSERT(rdg);
  return freerdp_shall_disconnect_context(rdg->context);
}
 
static BOOL rdg_read_all(rdpContext* context, rdpTls* tls, BYTE* buffer, size_t size,
                         rdg_http_encoding_context* transferEncoding)
{
  size_t readCount = 0;
  BYTE* pBuffer = buffer;
 
  while (readCount < size)
  {
    if (freerdp_shall_disconnect_context(context))
      return FALSE;
 
    int status = rdg_socket_read(tls->bio, pBuffer, size - readCount, transferEncoding);
    if (status <= 0)
    {
      if (!BIO_should_retry(tls->bio))
        return FALSE;
 
      Sleep(10);
      continue;
    }
 
    readCount += WINPR_ASSERTING_INT_CAST(uint32_t, status);
    pBuffer += WINPR_ASSERTING_INT_CAST(uint32_t, status);
  }
 
  return TRUE;
}
 
static wStream* rdg_receive_packet(rdpRdg* rdg)
{
  const size_t header = sizeof(RdgPacketHeader);
  size_t packetLength = 0;
  wStream* s = Stream_New(NULL, 1024);
 
  if (!s)
    return NULL;
 
  if (!rdg_read_all(rdg->context, rdg->tlsOut, Stream_Buffer(s), header, &rdg->transferEncoding))
  {
    Stream_Free(s, TRUE);
    return NULL;
  }
 
  Stream_Seek(s, 4);
  Stream_Read_UINT32(s, packetLength);
 
  if ((packetLength > INT_MAX) || !Stream_EnsureCapacity(s, packetLength) ||
      (packetLength < header))
  {
    Stream_Free(s, TRUE);
    return NULL;
  }
 
  if (!rdg_read_all(rdg->context, rdg->tlsOut, Stream_Buffer(s) + header, packetLength - header,
                    &rdg->transferEncoding))
  {
    Stream_Free(s, TRUE);
    return NULL;
  }
 
  Stream_SetLength(s, packetLength);
  return s;
}
 
static BOOL rdg_send_handshake(rdpRdg* rdg)
{
  BOOL status = FALSE;
  wStream* s = Stream_New(NULL, 14);
 
  if (!s)
    return FALSE;
 
  Stream_Write_UINT16(s, PKT_TYPE_HANDSHAKE_REQUEST); /* Type (2 bytes) */
  Stream_Write_UINT16(s, 0);                          /* Reserved (2 bytes) */
  Stream_Write_UINT32(s, 14);                         /* PacketLength (4 bytes) */
  Stream_Write_UINT8(s, 1);                           /* VersionMajor (1 byte) */
  Stream_Write_UINT8(s, 0);                           /* VersionMinor (1 byte) */
  Stream_Write_UINT16(s, 0);                          /* ClientVersion (2 bytes), must be 0 */
  Stream_Write_UINT16(s, rdg->extAuth);               /* ExtendedAuthentication (2 bytes) */
  Stream_SealLength(s);
  status = rdg_write_packet(rdg, s);
  Stream_Free(s, TRUE);
 
  if (status)
  {
    rdg->state = RDG_CLIENT_STATE_HANDSHAKE;
  }
 
  return status;
}
 
static BOOL rdg_send_extauth_sspi(rdpRdg* rdg)
{
  wStream* s = NULL;
  BOOL status = 0;
  UINT32 packetSize = 8 + 4 + 2;
 
  WINPR_ASSERT(rdg);
 
  const SecBuffer* authToken = credssp_auth_get_output_buffer(rdg->auth);
  if (!authToken)
    return FALSE;
  packetSize += authToken->cbBuffer;
 
  s = Stream_New(NULL, packetSize);
 
  if (!s)
    return FALSE;
 
  Stream_Write_UINT16(s, PKT_TYPE_EXTENDED_AUTH_MSG); /* Type (2 bytes) */
  Stream_Write_UINT16(s, 0);                          /* Reserved (2 bytes) */
  Stream_Write_UINT32(s, packetSize);                 /* PacketLength (4 bytes) */
  Stream_Write_UINT32(s, ERROR_SUCCESS);              /* Error code */
  Stream_Write_UINT16(s, (UINT16)authToken->cbBuffer);
  Stream_Write(s, authToken->pvBuffer, authToken->cbBuffer);
 
  Stream_SealLength(s);
  status = rdg_write_packet(rdg, s);
  Stream_Free(s, TRUE);
 
  return status;
}
 
static BOOL rdg_send_tunnel_request(rdpRdg* rdg)
{
  wStream* s = NULL;
  BOOL status = 0;
  UINT32 packetSize = 16;
  UINT16 fieldsPresent = 0;
  WCHAR* PAACookie = NULL;
  size_t PAACookieLen = 0;
  const UINT32 capabilities = HTTP_CAPABILITY_TYPE_QUAR_SOH |
                              HTTP_CAPABILITY_MESSAGING_CONSENT_SIGN |
                              HTTP_CAPABILITY_MESSAGING_SERVICE_MSG;
 
  if (rdg->extAuth == HTTP_EXTENDED_AUTH_PAA)
  {
    PAACookie =
        ConvertUtf8ToWCharAlloc(rdg->context->settings->GatewayAccessToken, &PAACookieLen);
 
    if (!PAACookie || (PAACookieLen > UINT16_MAX / sizeof(WCHAR)))
    {
      free(PAACookie);
      return FALSE;
    }
 
    PAACookieLen += 1; /* include \0 */
    packetSize += 2 + (UINT32)(PAACookieLen) * sizeof(WCHAR);
    fieldsPresent = HTTP_TUNNEL_PACKET_FIELD_PAA_COOKIE;
  }
 
  s = Stream_New(NULL, packetSize);
 
  if (!s)
  {
    free(PAACookie);
    return FALSE;
  }
 
  Stream_Write_UINT16(s, PKT_TYPE_TUNNEL_CREATE); /* Type (2 bytes) */
  Stream_Write_UINT16(s, 0);                      /* Reserved (2 bytes) */
  Stream_Write_UINT32(s, packetSize);             /* PacketLength (4 bytes) */
  Stream_Write_UINT32(s, capabilities);           /* CapabilityFlags (4 bytes) */
  Stream_Write_UINT16(s, fieldsPresent);          /* FieldsPresent (2 bytes) */
  Stream_Write_UINT16(s, 0);                      /* Reserved (2 bytes), must be 0 */
 
  if (PAACookie)
  {
    Stream_Write_UINT16(s, (UINT16)PAACookieLen * sizeof(WCHAR)); /* PAA cookie string length */
    Stream_Write_UTF16_String(s, PAACookie, PAACookieLen);
  }
 
  Stream_SealLength(s);
  status = rdg_write_packet(rdg, s);
  Stream_Free(s, TRUE);
  free(PAACookie);
 
  if (status)
  {
    rdg->state = RDG_CLIENT_STATE_TUNNEL_CREATE;
  }
 
  return status;
}
 
static BOOL rdg_send_tunnel_authorization(rdpRdg* rdg)
{
  wStream* s = NULL;
  BOOL status = 0;
  WINPR_ASSERT(rdg);
  size_t clientNameLen = 0;
  WCHAR* clientName = freerdp_settings_get_string_as_utf16(
      rdg->context->settings, FreeRDP_ClientHostname, &clientNameLen);
 
  clientNameLen++; // length including terminating '\0'
 
  const size_t packetSize = 12ull + clientNameLen * sizeof(WCHAR);
  if (!clientName || (clientNameLen >= UINT16_MAX / sizeof(WCHAR)) || (packetSize > UINT32_MAX))
  {
    free(clientName);
    return FALSE;
  }
 
  s = Stream_New(NULL, packetSize);
 
  if (!s)
  {
    free(clientName);
    return FALSE;
  }
 
  Stream_Write_UINT16(s, PKT_TYPE_TUNNEL_AUTH);                  /* Type (2 bytes) */
  Stream_Write_UINT16(s, 0);                                     /* Reserved (2 bytes) */
  Stream_Write_UINT32(s, (UINT32)packetSize);                    /* PacketLength (4 bytes) */
  Stream_Write_UINT16(s, 0);                                     /* FieldsPresent (2 bytes) */
  Stream_Write_UINT16(s, (UINT16)clientNameLen * sizeof(WCHAR)); /* Client name string length */
  Stream_Write_UTF16_String(s, clientName, clientNameLen);
  Stream_SealLength(s);
  status = rdg_write_packet(rdg, s);
  Stream_Free(s, TRUE);
  free(clientName);
 
  if (status)
  {
    rdg->state = RDG_CLIENT_STATE_TUNNEL_AUTHORIZE;
  }
 
  return status;
}
 
static BOOL rdg_send_channel_create(rdpRdg* rdg)
{
  wStream* s = NULL;
  BOOL status = FALSE;
  WCHAR* serverName = NULL;
  size_t serverNameLen = 0;
 
  WINPR_ASSERT(rdg);
  serverName = freerdp_settings_get_string_as_utf16(rdg->context->settings,
                                                    FreeRDP_ServerHostname, &serverNameLen);
 
  serverNameLen++; // length including terminating '\0'
  const size_t packetSize = 16ull + serverNameLen * sizeof(WCHAR);
  if (!serverName || (serverNameLen >= UINT16_MAX / sizeof(WCHAR)) || (packetSize > UINT32_MAX))
    goto fail;
 
  s = Stream_New(NULL, packetSize);
 
  if (!s)
    goto fail;
 
  Stream_Write_UINT16(s, PKT_TYPE_CHANNEL_CREATE); /* Type (2 bytes) */
  Stream_Write_UINT16(s, 0);                       /* Reserved (2 bytes) */
  Stream_Write_UINT32(s, (UINT32)packetSize);      /* PacketLength (4 bytes) */
  Stream_Write_UINT8(s, 1);                        /* Number of resources. (1 byte) */
  Stream_Write_UINT8(s, 0);                        /* Number of alternative resources (1 byte) */
  Stream_Write_UINT16(s,
                      (UINT16)rdg->context->settings->ServerPort); /* Resource port (2 bytes) */
  Stream_Write_UINT16(s, 3);                                       /* Protocol number (2 bytes) */
  Stream_Write_UINT16(s, (UINT16)serverNameLen * sizeof(WCHAR));
  Stream_Write_UTF16_String(s, serverName, serverNameLen);
  Stream_SealLength(s);
  status = rdg_write_packet(rdg, s);
fail:
  free(serverName);
  Stream_Free(s, TRUE);
 
  if (status)
    rdg->state = RDG_CLIENT_STATE_CHANNEL_CREATE;
 
  return status;
}
 
static BOOL rdg_set_auth_header(rdpCredsspAuth* auth, HttpRequest* request)
{
  const SecBuffer* authToken = credssp_auth_get_output_buffer(auth);
  char* base64AuthToken = NULL;
 
  if (authToken)
  {
    if (authToken->cbBuffer > INT_MAX)
      return FALSE;
 
    base64AuthToken = crypto_base64_encode(authToken->pvBuffer, authToken->cbBuffer);
  }
 
  if (base64AuthToken)
  {
    BOOL rc = http_request_set_auth_scheme(request, credssp_auth_pkg_name(auth)) &&
              http_request_set_auth_param(request, base64AuthToken);
    free(base64AuthToken);
 
    if (!rc)
      return FALSE;
  }
 
  return TRUE;
}
 
static wStream* rdg_build_http_request(rdpRdg* rdg, const char* method,
                                       TRANSFER_ENCODING transferEncoding)
{
  wStream* s = NULL;
  HttpRequest* request = NULL;
  const char* uri = NULL;
 
  if (!rdg || !method)
    return NULL;
 
  uri = http_context_get_uri(rdg->http);
  request = http_request_new();
 
  if (!request)
    return NULL;
 
  if (!http_request_set_method(request, method) || !http_request_set_uri(request, uri))
    goto out;
 
  if (rdg->auth)
  {
    if (!rdg_set_auth_header(rdg->auth, request))
      goto out;
  }
 
  else if (rdg->extAuth == HTTP_EXTENDED_AUTH_BEARER)
  {
    http_request_set_auth_scheme(request, "Bearer");
    http_request_set_auth_param(request, rdg->context->settings->GatewayHttpExtAuthBearer);
  }
 
  http_request_set_transfer_encoding(request, transferEncoding);
 
  s = http_request_write(rdg->http, request);
out:
  http_request_free(request);
 
  if (s)
    Stream_SealLength(s);
 
  return s;
}
 
static BOOL rdg_recv_auth_token(wLog* log, rdpCredsspAuth* auth, HttpResponse* response)
{
  size_t len = 0;
  size_t authTokenLength = 0;
  BYTE* authTokenData = NULL;
  SecBuffer authToken = { 0 };
  int rc = 0;
 
  if (!auth || !response)
    return FALSE;
 
  const UINT16 StatusCode = http_response_get_status_code(response);
  switch (StatusCode)
  {
    case HTTP_STATUS_DENIED:
    case HTTP_STATUS_OK:
    case HTTP_STATUS_SWITCH_PROTOCOLS:
      break;
    default:
      http_response_log_error_status(log, WLOG_WARN, response);
      return FALSE;
  }
 
  const char* token64 = http_response_get_auth_token(response, credssp_auth_pkg_name(auth));
  if (!token64)
    return FALSE;
 
  len = strlen(token64);
 
  crypto_base64_decode(token64, len, &authTokenData, &authTokenLength);
 
  if (authTokenLength && authTokenData && (authTokenLength <= UINT32_MAX))
  {
    authToken.pvBuffer = authTokenData;
    authToken.cbBuffer = (UINT32)authTokenLength;
    credssp_auth_take_input_buffer(auth, &authToken);
  }
  else
    free(authTokenData);
 
  rc = credssp_auth_authenticate(auth);
  if (rc < 0)
    return FALSE;
 
  return TRUE;
}
 
static BOOL rdg_skip_seed_payload(rdpContext* context, rdpTls* tls, size_t lastResponseLength,
                                  rdg_http_encoding_context* transferEncoding)
{
  BYTE seed_payload[10] = { 0 };
  const size_t size = sizeof(seed_payload);
 
  /* Per [MS-TSGU] 3.3.5.1 step 4, after final OK response RDG server sends
   * random "seed" payload of limited size. In practice it's 10 bytes.
   */
  if (lastResponseLength < size)
  {
    if (!rdg_read_all(context, tls, seed_payload, size - lastResponseLength, transferEncoding))
    {
      return FALSE;
    }
  }
 
  return TRUE;
}
 
static BOOL rdg_process_handshake_response(rdpRdg* rdg, wStream* s)
{
  UINT32 errorCode = 0;
  UINT16 serverVersion = 0;
  UINT16 extendedAuth = 0;
  BYTE verMajor = 0;
  BYTE verMinor = 0;
  const char* error = NULL;
  WLog_Print(rdg->log, WLOG_DEBUG, "Handshake response received");
 
  if (rdg->state != RDG_CLIENT_STATE_HANDSHAKE)
  {
    return FALSE;
  }
 
  if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, 10))
    return FALSE;
 
  Stream_Read_UINT32(s, errorCode);
  Stream_Read_UINT8(s, verMajor);
  Stream_Read_UINT8(s, verMinor);
  Stream_Read_UINT16(s, serverVersion);
  Stream_Read_UINT16(s, extendedAuth);
  error = rpc_error_to_string(errorCode);
  WLog_Print(rdg->log, WLOG_DEBUG,
             "errorCode=%s, verMajor=%" PRId8 ", verMinor=%" PRId8 ", serverVersion=%" PRId16
             ", extendedAuth=%s",
             error, verMajor, verMinor, serverVersion, extended_auth_to_string(extendedAuth));
 
  if (FAILED((HRESULT)errorCode))
  {
    WLog_Print(rdg->log, WLOG_ERROR, "Handshake error %s", error);
    freerdp_set_last_error_log(rdg->context, errorCode);
    return FALSE;
  }
 
  if (rdg->extAuth == HTTP_EXTENDED_AUTH_SSPI_NTLM)
    return rdg_send_extauth_sspi(rdg);
 
  return rdg_send_tunnel_request(rdg);
}
 
static BOOL rdg_process_tunnel_response_optional(rdpRdg* rdg, wStream* s, UINT16 fieldsPresent)
{
  if (fieldsPresent & HTTP_TUNNEL_RESPONSE_FIELD_TUNNEL_ID)
  {
    /* Seek over tunnelId (4 bytes) */
    if (!Stream_SafeSeek(s, 4))
    {
      WLog_Print(rdg->log, WLOG_ERROR, "Short tunnelId, got %" PRIuz ", expected 4",
                 Stream_GetRemainingLength(s));
      return FALSE;
    }
  }
 
  if (fieldsPresent & HTTP_TUNNEL_RESPONSE_FIELD_CAPS)
  {
    UINT32 caps = 0;
    if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, 4))
      return FALSE;
 
    Stream_Read_UINT32(s, caps);
    WLog_Print(rdg->log, WLOG_DEBUG, "capabilities=%s", capabilities_enum_to_string(caps));
  }
 
  if (fieldsPresent & HTTP_TUNNEL_RESPONSE_FIELD_SOH_REQ)
  {
    /* Seek over nonce (20 bytes) */
    if (!Stream_SafeSeek(s, 20))
    {
      WLog_Print(rdg->log, WLOG_ERROR, "Short nonce, got %" PRIuz ", expected 20",
                 Stream_GetRemainingLength(s));
      return FALSE;
    }
 
    /* Read serverCert */
    if (!rdg_read_http_unicode_string(rdg->log, s, NULL, NULL))
    {
      WLog_Print(rdg->log, WLOG_ERROR, "Failed to read server certificate");
      return FALSE;
    }
  }
 
  if (fieldsPresent & HTTP_TUNNEL_RESPONSE_FIELD_CONSENT_MSG)
  {
    const WCHAR* msg = NULL;
    UINT16 msgLenBytes = 0;
    rdpContext* context = rdg->context;
 
    WINPR_ASSERT(context);
    WINPR_ASSERT(context->instance);
 
    /* Read message string and invoke callback */
    if (!rdg_read_http_unicode_string(rdg->log, s, &msg, &msgLenBytes))
    {
      WLog_Print(rdg->log, WLOG_ERROR, "Failed to read consent message");
      return FALSE;
    }
 
    return IFCALLRESULT(TRUE, context->instance->PresentGatewayMessage, context->instance,
                        GATEWAY_MESSAGE_CONSENT, TRUE, TRUE, msgLenBytes, msg);
  }
 
  return TRUE;
}
 
static BOOL rdg_process_tunnel_response(rdpRdg* rdg, wStream* s)
{
  UINT16 serverVersion = 0;
  UINT16 fieldsPresent = 0;
  UINT32 errorCode = 0;
  const char* error = NULL;
  WLog_Print(rdg->log, WLOG_DEBUG, "Tunnel response received");
 
  if (rdg->state != RDG_CLIENT_STATE_TUNNEL_CREATE)
  {
    return FALSE;
  }
 
  if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, 10))
    return FALSE;
 
  Stream_Read_UINT16(s, serverVersion);
  Stream_Read_UINT32(s, errorCode);
  Stream_Read_UINT16(s, fieldsPresent);
  Stream_Seek_UINT16(s); /* reserved */
  error = rpc_error_to_string(errorCode);
  WLog_Print(rdg->log, WLOG_DEBUG, "serverVersion=%" PRId16 ", errorCode=%s, fieldsPresent=%s",
             serverVersion, error, tunnel_response_fields_present_to_string(fieldsPresent));
 
  if (FAILED((HRESULT)errorCode))
  {
    WLog_Print(rdg->log, WLOG_ERROR, "Tunnel creation error %s", error);
    freerdp_set_last_error_log(rdg->context, errorCode);
    return FALSE;
  }
 
  if (!rdg_process_tunnel_response_optional(rdg, s, fieldsPresent))
    return FALSE;
 
  return rdg_send_tunnel_authorization(rdg);
}
 
static BOOL rdg_process_tunnel_authorization_response(rdpRdg* rdg, wStream* s)
{
  UINT32 errorCode = 0;
  UINT16 fieldsPresent = 0;
  const char* error = NULL;
  WLog_Print(rdg->log, WLOG_DEBUG, "Tunnel authorization received");
 
  if (rdg->state != RDG_CLIENT_STATE_TUNNEL_AUTHORIZE)
  {
    return FALSE;
  }
 
  if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, 8))
    return FALSE;
 
  Stream_Read_UINT32(s, errorCode);
  Stream_Read_UINT16(s, fieldsPresent);
  Stream_Seek_UINT16(s); /* reserved */
  error = rpc_error_to_string(errorCode);
  WLog_Print(rdg->log, WLOG_DEBUG, "errorCode=%s, fieldsPresent=%s", error,
             tunnel_authorization_response_fields_present_to_string(fieldsPresent));
 
  /* [MS-TSGU] 3.7.5.2.7 */
  if (errorCode != S_OK && errorCode != E_PROXY_QUARANTINE_ACCESSDENIED)
  {
    WLog_Print(rdg->log, WLOG_ERROR, "Tunnel authorization error %s", error);
    freerdp_set_last_error_log(rdg->context, errorCode);
    return FALSE;
  }
 
  if (fieldsPresent & HTTP_TUNNEL_AUTH_RESPONSE_FIELD_REDIR_FLAGS)
  {
    UINT32 redirFlags = 0;
    if (!Stream_CheckAndLogRequiredCapacityWLog(rdg->log, s, 4))
      return FALSE;
    Stream_Read_UINT32(s, redirFlags);
 
    rdpContext* context = rdg->context;
    if (!utils_apply_gateway_policy(rdg->log, context, redirFlags, "RDG"))
      return FALSE;
  }
 
  if (fieldsPresent & HTTP_TUNNEL_AUTH_RESPONSE_FIELD_IDLE_TIMEOUT)
  {
    UINT32 idleTimeout = 0;
    if (!Stream_CheckAndLogRequiredCapacityWLog(rdg->log, s, 4))
      return FALSE;
    Stream_Read_UINT32(s, idleTimeout);
    WLog_Print(rdg->log, WLOG_DEBUG, "[IDLE_TIMEOUT] idleTimeout=%" PRIu32 ": TODO: unused",
               idleTimeout);
  }
 
  if (fieldsPresent & HTTP_TUNNEL_AUTH_RESPONSE_FIELD_SOH_RESPONSE)
  {
    UINT16 cbLen = 0;
    if (!Stream_CheckAndLogRequiredCapacityWLog(rdg->log, s, 2))
      return FALSE;
    Stream_Read_UINT16(s, cbLen);
 
    WLog_Print(rdg->log, WLOG_DEBUG, "[SOH_RESPONSE] cbLen=%" PRIu16 ": TODO: unused", cbLen);
    if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, cbLen))
      return FALSE;
    Stream_Seek(s, cbLen);
  }
 
  return rdg_send_channel_create(rdg);
}
 
static BOOL rdg_process_extauth_sspi(rdpRdg* rdg, wStream* s)
{
  INT32 errorCode = 0;
  UINT16 authBlobLen = 0;
  SecBuffer authToken = { 0 };
  BYTE* authTokenData = NULL;
 
  WINPR_ASSERT(rdg);
 
  Stream_Read_INT32(s, errorCode);
  Stream_Read_UINT16(s, authBlobLen);
 
  if (errorCode != ERROR_SUCCESS)
  {
    WLog_Print(rdg->log, WLOG_ERROR, "EXTAUTH_SSPI_NTLM failed with error %s [0x%08X]",
               GetSecurityStatusString(errorCode), WINPR_CXX_COMPAT_CAST(UINT32, errorCode));
    return FALSE;
  }
 
  if (authBlobLen == 0)
  {
    if (credssp_auth_is_complete(rdg->auth))
    {
      credssp_auth_free(rdg->auth);
      rdg->auth = NULL;
      return rdg_send_tunnel_request(rdg);
    }
    return FALSE;
  }
 
  authTokenData = malloc(authBlobLen);
  if (authTokenData == NULL)
    return FALSE;
  Stream_Read(s, authTokenData, authBlobLen);
 
  authToken.pvBuffer = authTokenData;
  authToken.cbBuffer = authBlobLen;
 
  credssp_auth_take_input_buffer(rdg->auth, &authToken);
 
  if (credssp_auth_authenticate(rdg->auth) < 0)
    return FALSE;
 
  if (credssp_auth_have_output_token(rdg->auth))
    return rdg_send_extauth_sspi(rdg);
 
  return FALSE;
}
 
static BOOL rdg_process_channel_response(rdpRdg* rdg, wStream* s)
{
  UINT16 fieldsPresent = 0;
  UINT32 errorCode = 0;
  const char* error = NULL;
  WLog_Print(rdg->log, WLOG_DEBUG, "Channel response received");
 
  if (rdg->state != RDG_CLIENT_STATE_CHANNEL_CREATE)
  {
    return FALSE;
  }
 
  if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, 8))
    return FALSE;
 
  Stream_Read_UINT32(s, errorCode);
  Stream_Read_UINT16(s, fieldsPresent);
  Stream_Seek_UINT16(s); /* reserved */
  error = rpc_error_to_string(errorCode);
  WLog_Print(rdg->log, WLOG_DEBUG, "channel response errorCode=%s, fieldsPresent=%s", error,
             channel_response_fields_present_to_string(fieldsPresent));
 
  if (FAILED((HRESULT)errorCode))
  {
    WLog_Print(rdg->log, WLOG_ERROR, "channel response errorCode=%s, fieldsPresent=%s", error,
               channel_response_fields_present_to_string(fieldsPresent));
    freerdp_set_last_error_log(rdg->context, errorCode);
    return FALSE;
  }
 
  rdg->state = RDG_CLIENT_STATE_OPENED;
  return TRUE;
}
 
static BOOL rdg_process_packet(rdpRdg* rdg, wStream* s)
{
  BOOL status = TRUE;
  UINT16 type = 0;
  UINT32 packetLength = 0;
  Stream_SetPosition(s, 0);
 
  if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, 8))
    return FALSE;
 
  Stream_Read_UINT16(s, type);
  Stream_Seek_UINT16(s); /* reserved */
  Stream_Read_UINT32(s, packetLength);
 
  if (Stream_Length(s) < packetLength)
  {
    WLog_Print(rdg->log, WLOG_ERROR, "Short packet %" PRIuz ", expected %" PRIu32,
               Stream_Length(s), packetLength);
    return FALSE;
  }
 
  switch (type)
  {
    case PKT_TYPE_HANDSHAKE_RESPONSE:
      status = rdg_process_handshake_response(rdg, s);
      break;
 
    case PKT_TYPE_TUNNEL_RESPONSE:
      status = rdg_process_tunnel_response(rdg, s);
      break;
 
    case PKT_TYPE_TUNNEL_AUTH_RESPONSE:
      status = rdg_process_tunnel_authorization_response(rdg, s);
      break;
 
    case PKT_TYPE_CHANNEL_RESPONSE:
      status = rdg_process_channel_response(rdg, s);
      break;
 
    case PKT_TYPE_DATA:
      WLog_Print(rdg->log, WLOG_ERROR, "Unexpected packet type DATA");
      return FALSE;
 
    case PKT_TYPE_EXTENDED_AUTH_MSG:
      status = rdg_process_extauth_sspi(rdg, s);
      break;
 
    default:
      WLog_Print(rdg->log, WLOG_ERROR, "PKG TYPE 0x%x not implemented", type);
      return FALSE;
  }
 
  return status;
}
 
DWORD rdg_get_event_handles(rdpRdg* rdg, HANDLE* events, DWORD count)
{
  DWORD nCount = 0;
  WINPR_ASSERT(rdg != NULL);
 
  if (rdg->tlsOut && rdg->tlsOut->bio)
  {
    if (events && (nCount < count))
    {
      BIO_get_event(rdg->tlsOut->bio, &events[nCount]);
      nCount++;
    }
    else
      return 0;
  }
 
  /* We just need the read event handle even in non-websocket mode. */
 
  return nCount;
}
 
static BOOL rdg_get_gateway_credentials(rdpContext* context, rdp_auth_reason reason)
{
  freerdp* instance = context->instance;
 
  auth_status rc = utils_authenticate_gateway(instance, reason);
  switch (rc)
  {
    case AUTH_SUCCESS:
    case AUTH_SKIP:
      return TRUE;
    case AUTH_CANCELLED:
      freerdp_set_last_error_log(instance->context, FREERDP_ERROR_CONNECT_CANCELLED);
      return FALSE;
    case AUTH_NO_CREDENTIALS:
      WLog_INFO(TAG, "No credentials provided - using NULL identity");
      return TRUE;
    case AUTH_FAILED:
    default:
      return FALSE;
  }
}
 
static BOOL rdg_auth_init(rdpRdg* rdg, rdpTls* tls, TCHAR* authPkg)
{
  rdpContext* context = rdg->context;
  rdpSettings* settings = context->settings;
  SEC_WINNT_AUTH_IDENTITY identity = { 0 };
  int rc = 0;
 
  rdg->auth = credssp_auth_new(context);
  if (!rdg->auth)
    return FALSE;
 
  if (!credssp_auth_init(rdg->auth, authPkg, tls->Bindings))
    return FALSE;
 
  BOOL doSCLogon = freerdp_settings_get_bool(settings, FreeRDP_SmartcardLogon);
  if (doSCLogon)
  {
    if (!smartcard_getCert(context, &rdg->smartcard, TRUE))
      return FALSE;
 
    if (!rdg_get_gateway_credentials(context, AUTH_SMARTCARD_PIN))
      return FALSE;
  }
  else
  {
    if (!rdg_get_gateway_credentials(context, GW_AUTH_RDG))
      return FALSE;
 
    /* Auth callback might changed logon to smartcard so check again */
    doSCLogon = freerdp_settings_get_bool(settings, FreeRDP_SmartcardLogon);
    if (doSCLogon && !smartcard_getCert(context, &rdg->smartcard, TRUE))
      return FALSE;
  }
 
  SEC_WINNT_AUTH_IDENTITY* identityArg = &identity;
  if (doSCLogon)
  {
    if (!identity_set_from_smartcard_hash(&identity, settings, FreeRDP_GatewayUsername,
                                          FreeRDP_GatewayDomain, FreeRDP_GatewayPassword,
                                          rdg->smartcard->sha1Hash,
                                          sizeof(rdg->smartcard->sha1Hash)))
      return FALSE;
  }
  else
  {
    if (!identity_set_from_settings(&identity, settings, FreeRDP_GatewayUsername,
                                    FreeRDP_GatewayDomain, FreeRDP_GatewayPassword))
      return FALSE;
 
    if (!settings->GatewayUsername)
      identityArg = NULL;
  }
 
  if (!credssp_auth_setup_client(rdg->auth, "HTTP", settings->GatewayHostname, identityArg,
                                 rdg->smartcard ? rdg->smartcard->pkinitArgs : NULL))
  {
    sspi_FreeAuthIdentity(&identity);
    return FALSE;
  }
  sspi_FreeAuthIdentity(&identity);
 
  credssp_auth_set_flags(rdg->auth, ISC_REQ_CONFIDENTIALITY | ISC_REQ_MUTUAL_AUTH);
 
  rc = credssp_auth_authenticate(rdg->auth);
  if (rc < 0)
    return FALSE;
 
  return TRUE;
}
 
static BOOL rdg_send_http_request(rdpRdg* rdg, rdpTls* tls, const char* method,
                                  TRANSFER_ENCODING transferEncoding)
{
  int status = -1;
  wStream* s = rdg_build_http_request(rdg, method, transferEncoding);
 
  if (!s)
    return FALSE;
 
  const size_t sz = Stream_Length(s);
  status = freerdp_tls_write_all(tls, Stream_Buffer(s), sz);
 
  Stream_Free(s, TRUE);
  return (status >= 0);
}
 
static BOOL rdg_tls_connect(rdpRdg* rdg, rdpTls* tls, const char* peerAddress, UINT32 timeout)
{
  long status = 0;
  BIO* layerBio = NULL;
  BIO* bufferedBio = NULL;
  rdpTransportLayer* layer = NULL;
  rdpSettings* settings = rdg->context->settings;
  rdpTransport* transport = freerdp_get_transport(rdg->context);
  const char* peerHostname = settings->GatewayHostname;
  UINT16 peerPort = (UINT16)settings->GatewayPort;
  const char* proxyUsername = NULL;
  const char* proxyPassword = NULL;
  BOOL isProxyConnection =
      proxy_prepare(settings, &peerHostname, &peerPort, &proxyUsername, &proxyPassword);
 
  if (settings->GatewayPort > UINT16_MAX)
    return FALSE;
 
  layer = transport_connect_layer(transport, peerAddress ? peerAddress : peerHostname, peerPort,
                                  timeout);
 
  if (!layer)
  {
    return FALSE;
  }
 
  layerBio = BIO_new(BIO_s_transport_layer());
  if (!layerBio)
  {
    transport_layer_free(layer);
    return FALSE;
  }
  BIO_set_data(layerBio, layer);
 
  bufferedBio = BIO_new(BIO_s_buffered_socket());
  if (!bufferedBio)
  {
    BIO_free_all(layerBio);
    return FALSE;
  }
 
  bufferedBio = BIO_push(bufferedBio, layerBio);
  status = BIO_set_nonblock(bufferedBio, TRUE);
 
  if (isProxyConnection)
  {
    if (!proxy_connect(rdg->context, bufferedBio, proxyUsername, proxyPassword,
                       settings->GatewayHostname, (UINT16)settings->GatewayPort))
    {
      BIO_free_all(bufferedBio);
      return FALSE;
    }
  }
 
  if (!status)
  {
    BIO_free_all(bufferedBio);
    return FALSE;
  }
 
  tls->hostname = settings->GatewayHostname;
  tls->port = WINPR_ASSERTING_INT_CAST(int32_t, MIN(UINT16_MAX, settings->GatewayPort));
  tls->isGatewayTransport = TRUE;
  status = freerdp_tls_connect(tls, bufferedBio);
  if (status < 1)
  {
    rdpContext* context = rdg->context;
    if (status < 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 (status >= 1);
}
 
static BOOL rdg_establish_data_connection(rdpRdg* rdg, rdpTls* tls, const char* method,
                                          const char* peerAddress, UINT32 timeout,
                                          BOOL* rpcFallback)
{
  char buffer[64] = { 0 };
  HttpResponse* response = NULL;
 
  if (!rdg_tls_connect(rdg, tls, peerAddress, timeout))
    return FALSE;
 
  WINPR_ASSERT(rpcFallback);
  if (rdg->context->settings->GatewayHttpExtAuthBearer && rdg->extAuth == HTTP_EXTENDED_AUTH_NONE)
    rdg->extAuth = HTTP_EXTENDED_AUTH_BEARER;
  if (rdg->extAuth == HTTP_EXTENDED_AUTH_NONE)
  {
    if (!rdg_auth_init(rdg, tls, AUTH_PKG))
      return FALSE;
 
    if (!rdg_send_http_request(rdg, tls, method, TransferEncodingIdentity))
      return FALSE;
 
    response = http_response_recv(tls, TRUE);
    /* MS RD Gateway seems to just terminate the tls connection without
     * sending an answer if it is not happy with the http request */
    if (!response)
    {
      WLog_Print(rdg->log, WLOG_INFO, "RD Gateway HTTP transport broken.");
      *rpcFallback = TRUE;
      return FALSE;
    }
 
    (void)http_response_extract_cookies(response, rdg->http);
 
    const UINT16 StatusCode = http_response_get_status_code(response);
    switch (StatusCode)
    {
      case HTTP_STATUS_GONE:
      case HTTP_STATUS_FORBIDDEN:
      case HTTP_STATUS_NOT_FOUND:
      {
        WLog_Print(rdg->log, WLOG_INFO, "RD Gateway does not support HTTP transport.");
        http_response_log_error_status(rdg->log, WLOG_DEBUG, response);
        *rpcFallback = TRUE;
 
        http_response_free(response);
        return FALSE;
      }
      case HTTP_STATUS_OK:
        break;
 
      case HTTP_STATUS_DENIED:
        http_response_log_error_status(rdg->log, WLOG_DEBUG, response);
        break;
 
      default:
        http_response_log_error_status(rdg->log, WLOG_WARN, response);
        break;
    }
 
    while (!credssp_auth_is_complete(rdg->auth))
    {
      if (!rdg_recv_auth_token(rdg->log, rdg->auth, response))
      {
        http_response_free(response);
        return FALSE;
      }
 
      if (credssp_auth_have_output_token(rdg->auth))
      {
        http_response_free(response);
 
        if (!rdg_send_http_request(rdg, tls, method, TransferEncodingIdentity))
          return FALSE;
 
        response = http_response_recv(tls, TRUE);
        if (!response)
        {
          WLog_Print(rdg->log, WLOG_INFO, "RD Gateway HTTP transport broken.");
          *rpcFallback = TRUE;
          return FALSE;
        }
        (void)http_response_extract_cookies(response, rdg->http);
      }
    }
    credssp_auth_free(rdg->auth);
    rdg->auth = NULL;
  }
  else
  {
    credssp_auth_free(rdg->auth);
    rdg->auth = NULL;
 
    if (!rdg_send_http_request(rdg, tls, method, TransferEncodingIdentity))
      return FALSE;
 
    response = http_response_recv(tls, TRUE);
 
    if (!response)
    {
      WLog_Print(rdg->log, WLOG_INFO, "RD Gateway HTTP transport broken.");
      *rpcFallback = TRUE;
      return FALSE;
    }
    (void)http_response_extract_cookies(response, rdg->http);
  }
 
  const UINT16 statusCode = http_response_get_status_code(response);
  const size_t bodyLength = http_response_get_body_length(response);
  const TRANSFER_ENCODING encoding = http_response_get_transfer_encoding(response);
  const BOOL isWebsocket = http_response_is_websocket(rdg->http, response);
 
  WLog_Print(rdg->log, WLOG_DEBUG, "%s authorization result: %s", method,
             freerdp_http_status_string_format(statusCode, buffer, ARRAYSIZE(buffer)));
 
  switch (statusCode)
  {
    case HTTP_STATUS_OK:
      /* old rdg endpoint without websocket support, don't request websocket for RDG_IN_DATA
       */
      http_context_enable_websocket_upgrade(rdg->http, FALSE);
      http_response_free(response);
      break;
    case HTTP_STATUS_DENIED:
      freerdp_set_last_error_log(rdg->context, FREERDP_ERROR_CONNECT_ACCESS_DENIED);
      http_response_free(response);
      return FALSE;
    case HTTP_STATUS_SWITCH_PROTOCOLS:
      http_response_free(response);
      if (!isWebsocket)
      {
        /*
         * webserver is broken, a fallback may be possible here
         * but only if already tested with oppurtonistic upgrade
         */
        if (http_context_is_websocket_upgrade_enabled(rdg->http))
        {
          long fd = BIO_get_fd(tls->bio, NULL);
          if (fd >= 0)
            closesocket((SOCKET)fd);
          http_context_enable_websocket_upgrade(rdg->http, FALSE);
          return rdg_establish_data_connection(rdg, tls, method, peerAddress, timeout,
                                               rpcFallback);
        }
        return FALSE;
      }
 
      rdg->transferEncoding.isWebsocketTransport = TRUE;
      if (!websocket_context_reset(rdg->transferEncoding.context.websocket))
        return FALSE;
 
      if (rdg->extAuth == HTTP_EXTENDED_AUTH_SSPI_NTLM)
      {
        /* create a new auth context for SSPI_NTLM. This must be done after the last
         * rdg_send_http_request */
        if (!rdg_auth_init(rdg, tls, NTLM_SSP_NAME))
          return FALSE;
      }
      return TRUE;
    default:
      http_response_log_error_status(rdg->log, WLOG_WARN, response);
      http_response_free(response);
      return FALSE;
  }
 
  if (strcmp(method, "RDG_OUT_DATA") == 0)
  {
    if (encoding == TransferEncodingChunked)
    {
      rdg->transferEncoding.httpTransferEncoding = TransferEncodingChunked;
      rdg->transferEncoding.context.chunked.nextOffset = 0;
      rdg->transferEncoding.context.chunked.headerFooterPos = 0;
      rdg->transferEncoding.context.chunked.state = ChunkStateLenghHeader;
    }
    if (!rdg_skip_seed_payload(rdg->context, tls, bodyLength, &rdg->transferEncoding))
    {
      return FALSE;
    }
  }
  else
  {
    if (!rdg_send_http_request(rdg, tls, method, TransferEncodingChunked))
      return FALSE;
 
    if (rdg->extAuth == HTTP_EXTENDED_AUTH_SSPI_NTLM)
    {
      /* create a new auth context for SSPI_NTLM. This must be done after the last
       * rdg_send_http_request (RDG_IN_DATA is always after RDG_OUT_DATA) */
      if (!rdg_auth_init(rdg, tls, NTLM_SSP_NAME))
        return FALSE;
    }
  }
 
  return TRUE;
}
 
static BOOL rdg_tunnel_connect(rdpRdg* rdg)
{
  BOOL status = 0;
  wStream* s = NULL;
  rdg_send_handshake(rdg);
 
  while (rdg->state < RDG_CLIENT_STATE_OPENED)
  {
    status = FALSE;
    s = rdg_receive_packet(rdg);
 
    if (s)
    {
      status = rdg_process_packet(rdg, s);
      Stream_Free(s, TRUE);
    }
 
    if (!status)
    {
      WINPR_ASSERT(rdg);
      WINPR_ASSERT(rdg->context);
      WINPR_ASSERT(rdg->context->rdp);
      transport_set_layer(rdg->context->rdp->transport, TRANSPORT_LAYER_CLOSED);
      return FALSE;
    }
  }
 
  return TRUE;
}
 
BOOL rdg_connect(rdpRdg* rdg, DWORD timeout, BOOL* rpcFallback)
{
  BOOL status = 0;
  SOCKET outConnSocket = 0;
  char* peerAddress = NULL;
  BOOL rpcFallbackLocal = FALSE;
 
  WINPR_ASSERT(rdg != NULL);
  freerdp_set_last_error(rdg->context, ERROR_SUCCESS);
  status = rdg_establish_data_connection(rdg, rdg->tlsOut, "RDG_OUT_DATA", NULL, timeout,
                                         &rpcFallbackLocal);
 
  if (status)
  {
    if (rdg->transferEncoding.isWebsocketTransport)
    {
      WLog_Print(rdg->log, WLOG_DEBUG, "Upgraded to websocket. RDG_IN_DATA not required");
    }
    else
    {
      /* Establish IN connection with the same peer/server as OUT connection,
       * even when server hostname resolves to different IP addresses.
       */
      BIO_get_socket(rdg->tlsOut->underlying, &outConnSocket);
      peerAddress = freerdp_tcp_get_peer_address(outConnSocket);
      status = rdg_establish_data_connection(rdg, rdg->tlsIn, "RDG_IN_DATA", peerAddress,
                                             timeout, &rpcFallbackLocal);
      free(peerAddress);
    }
  }
 
  if (rpcFallback)
    *rpcFallback = rpcFallbackLocal;
 
  if (!status)
  {
    WINPR_ASSERT(rdg);
    WINPR_ASSERT(rdg->context);
    WINPR_ASSERT(rdg->context->rdp);
    if (rpcFallbackLocal)
    {
      http_context_enable_websocket_upgrade(rdg->http, FALSE);
      credssp_auth_free(rdg->auth);
      rdg->auth = NULL;
    }
 
    transport_set_layer(rdg->context->rdp->transport, TRANSPORT_LAYER_CLOSED);
    return FALSE;
  }
 
  status = rdg_tunnel_connect(rdg);
 
  if (!status)
    return FALSE;
 
  return TRUE;
}
 
static int rdg_write_websocket_data_packet(rdpRdg* rdg, const BYTE* buf, int isize)
{
  WINPR_ASSERT(rdg);
  if (isize < 0)
    return -1;
 
  const size_t payloadSize = (size_t)isize + 10;
  union
  {
    UINT32 u32;
    UINT8 u8[4];
  } maskingKey;
 
  wStream* sWS =
      websocket_context_packet_new(payloadSize, WebsocketBinaryOpcode, &maskingKey.u32);
  if (!sWS)
    return FALSE;
 
  Stream_Write_UINT16(
      sWS, WINPR_ASSERTING_INT_CAST(
               uint16_t, PKT_TYPE_DATA ^ (maskingKey.u8[0] | maskingKey.u8[1] << 8))); /* Type */
  Stream_Write_UINT16(
      sWS, WINPR_ASSERTING_INT_CAST(
               uint16_t, 0 ^ (maskingKey.u8[2] | maskingKey.u8[3] << 8))); /* Reserved */
  Stream_Write_UINT32(
      sWS, WINPR_ASSERTING_INT_CAST(uint32_t, payloadSize ^ maskingKey.u32)); /* Packet length */
  Stream_Write_UINT16(
      sWS, WINPR_ASSERTING_INT_CAST(
               uint16_t, isize ^ (maskingKey.u8[0] | maskingKey.u8[1] << 8))); /* Data size */
 
  /* masking key is now off by 2 bytes. fix that */
  maskingKey.u32 = (maskingKey.u32 & 0xffff) << 16 | (maskingKey.u32 >> 16);
 
  WINPR_ASSERT(rdg->tlsOut);
  wStream sPacket = { 0 };
  Stream_StaticConstInit(&sPacket, buf, (size_t)isize);
  if (!websocket_context_mask_and_send(rdg->tlsOut->bio, sWS, &sPacket, maskingKey.u32))
    return -1;
 
  return isize;
}
 
static int rdg_write_chunked_data_packet(rdpRdg* rdg, const BYTE* buf, int isize)
{
  int status = 0;
  size_t len = 0;
  wStream* sChunk = NULL;
 
  if (isize > UINT16_MAX)
    return -1;
 
  const size_t size = (size_t)isize;
  if (size < 1)
    return 0;
 
  const size_t packetSize = size + 10;
  char chunkSize[11] = { 0 };
  (void)sprintf_s(chunkSize, sizeof(chunkSize), "%" PRIxz "\r\n", packetSize);
  sChunk = Stream_New(NULL, strnlen(chunkSize, sizeof(chunkSize)) + packetSize + 2);
 
  if (!sChunk)
    return -1;
 
  Stream_Write(sChunk, chunkSize, strnlen(chunkSize, sizeof(chunkSize)));
  Stream_Write_UINT16(sChunk, PKT_TYPE_DATA);      /* Type */
  Stream_Write_UINT16(sChunk, 0);                  /* Reserved */
  Stream_Write_UINT32(sChunk, (UINT32)packetSize); /* Packet length */
  Stream_Write_UINT16(sChunk, (UINT16)size);       /* Data size */
  Stream_Write(sChunk, buf, size);                 /* Data */
  Stream_Write(sChunk, "\r\n", 2);
  Stream_SealLength(sChunk);
  len = Stream_Length(sChunk);
 
  status = freerdp_tls_write_all(rdg->tlsIn, Stream_Buffer(sChunk), len);
  Stream_Free(sChunk, TRUE);
 
  if (status < 0)
    return -1;
 
  return (int)size;
}
 
static int rdg_write_data_packet(rdpRdg* rdg, const BYTE* buf, int isize)
{
  WINPR_ASSERT(rdg);
  if (rdg->transferEncoding.isWebsocketTransport)
    return rdg_write_websocket_data_packet(rdg, buf, isize);
  else
    return rdg_write_chunked_data_packet(rdg, buf, isize);
}
 
static BOOL rdg_process_close_packet(rdpRdg* rdg, wStream* s)
{
  int status = -1;
  wStream* sClose = NULL;
  UINT32 errorCode = 0;
  UINT32 packetSize = 12;
 
  /* Read error code */
  if (!Stream_CheckAndLogRequiredLengthWLog(rdg->log, s, 4))
    return FALSE;
  Stream_Read_UINT32(s, errorCode);
 
  if (errorCode != 0)
    freerdp_set_last_error_log(rdg->context, errorCode);
 
  sClose = Stream_New(NULL, packetSize);
  if (!sClose)
    return FALSE;
 
  Stream_Write_UINT16(sClose, PKT_TYPE_CLOSE_CHANNEL_RESPONSE); /* Type */
  Stream_Write_UINT16(sClose, 0);                               /* Reserved */
  Stream_Write_UINT32(sClose, packetSize);                      /* Packet length */
  Stream_Write_UINT32(sClose, 0);                               /* Status code */
  Stream_SealLength(sClose);
  status = rdg_write_packet(rdg, sClose);
  Stream_Free(sClose, TRUE);
 
  return (status < 0 ? FALSE : TRUE);
}
 
static BOOL rdg_process_keep_alive_packet(rdpRdg* rdg)
{
  int status = -1;
  wStream* sKeepAlive = NULL;
  size_t packetSize = 8;
 
  sKeepAlive = Stream_New(NULL, packetSize);
 
  if (!sKeepAlive)
    return FALSE;
 
  Stream_Write_UINT16(sKeepAlive, PKT_TYPE_KEEPALIVE); /* Type */
  Stream_Write_UINT16(sKeepAlive, 0);                  /* Reserved */
  Stream_Write_UINT32(sKeepAlive, (UINT32)packetSize); /* Packet length */
  Stream_SealLength(sKeepAlive);
  status = rdg_write_packet(rdg, sKeepAlive);
  Stream_Free(sKeepAlive, TRUE);
 
  return (status < 0 ? FALSE : TRUE);
}
 
static BOOL rdg_process_service_message(rdpRdg* rdg, wStream* s)
{
  const WCHAR* msg = NULL;
  UINT16 msgLenBytes = 0;
  rdpContext* context = rdg->context;
  WINPR_ASSERT(context);
  WINPR_ASSERT(context->instance);
 
  /* Read message string */
  if (!rdg_read_http_unicode_string(rdg->log, s, &msg, &msgLenBytes))
  {
    WLog_Print(rdg->log, WLOG_ERROR, "Failed to read string");
    return FALSE;
  }
 
  return IFCALLRESULT(TRUE, context->instance->PresentGatewayMessage, context->instance,
                      GATEWAY_MESSAGE_SERVICE, TRUE, FALSE, msgLenBytes, msg);
}
 
static BOOL rdg_process_unknown_packet(rdpRdg* rdg, int type)
{
  WINPR_UNUSED(rdg);
  WINPR_UNUSED(type);
  WLog_Print(rdg->log, WLOG_WARN, "Unknown Control Packet received: %" PRIX32,
             WINPR_CXX_COMPAT_CAST(UINT32, type));
  return TRUE;
}
 
static BOOL rdg_process_control_packet(rdpRdg* rdg, int type, size_t packetLength)
{
  wStream* s = NULL;
  size_t readCount = 0;
  int status = 0;
  size_t payloadSize = packetLength - sizeof(RdgPacketHeader);
 
  if (packetLength < sizeof(RdgPacketHeader))
    return FALSE;
 
  // NOLINTNEXTLINE(bugprone-sizeof-expression)
  WINPR_ASSERT(sizeof(RdgPacketHeader) < INT_MAX);
 
  if (payloadSize)
  {
    s = Stream_New(NULL, payloadSize);
 
    if (!s)
      return FALSE;
 
    while (readCount < payloadSize)
    {
      if (rdg_shall_abort(rdg))
      {
        Stream_Free(s, TRUE);
        return FALSE;
      }
      status = rdg_socket_read(rdg->tlsOut->bio, Stream_Pointer(s), payloadSize - readCount,
                               &rdg->transferEncoding);
 
      if (status <= 0)
      {
        if (!BIO_should_retry(rdg->tlsOut->bio))
        {
          Stream_Free(s, TRUE);
          return FALSE;
        }
 
        continue;
      }
 
      Stream_Seek(s, (size_t)status);
      readCount += (size_t)status;
 
      if (readCount > INT_MAX)
      {
        Stream_Free(s, TRUE);
        return FALSE;
      }
    }
 
    Stream_SetPosition(s, 0);
  }
 
  switch (type)
  {
    case PKT_TYPE_CLOSE_CHANNEL:
      EnterCriticalSection(&rdg->writeSection);
      status = rdg_process_close_packet(rdg, s);
      LeaveCriticalSection(&rdg->writeSection);
      break;
 
    case PKT_TYPE_KEEPALIVE:
      EnterCriticalSection(&rdg->writeSection);
      status = rdg_process_keep_alive_packet(rdg);
      LeaveCriticalSection(&rdg->writeSection);
      break;
 
    case PKT_TYPE_SERVICE_MESSAGE:
      if (!s)
      {
        WLog_Print(rdg->log, WLOG_ERROR,
                   "PKT_TYPE_SERVICE_MESSAGE requires payload but none was sent");
        return FALSE;
      }
      status = rdg_process_service_message(rdg, s);
      break;
 
    case PKT_TYPE_REAUTH_MESSAGE:
    default:
      status = rdg_process_unknown_packet(rdg, type);
      break;
  }
 
  Stream_Free(s, TRUE);
  return status;
}
 
static int rdg_read_data_packet(rdpRdg* rdg, BYTE* buffer, size_t size)
{
  RdgPacketHeader header = { 0 };
  size_t readCount = 0;
  size_t readSize = 0;
  int status = 0;
 
  if (!rdg->packetRemainingCount)
  {
    // NOLINTNEXTLINE(bugprone-sizeof-expression)
    WINPR_ASSERT(sizeof(RdgPacketHeader) < INT_MAX);
 
    while (readCount < sizeof(RdgPacketHeader))
    {
      if (rdg_shall_abort(rdg))
        return -1;
 
      status = rdg_socket_read(rdg->tlsOut->bio, (BYTE*)(&header) + readCount,
                               sizeof(RdgPacketHeader) - readCount, &rdg->transferEncoding);
 
      if (status <= 0)
      {
        if (!BIO_should_retry(rdg->tlsOut->bio))
          return -1;
 
        if (!readCount)
          return 0;
 
        BIO_wait_read(rdg->tlsOut->bio, 50);
        continue;
      }
 
      readCount += (size_t)status;
 
      if (readCount > INT_MAX)
        return -1;
    }
 
    if (header.type != PKT_TYPE_DATA)
    {
      status = rdg_process_control_packet(rdg, header.type, header.packetLength);
 
      if (!status)
        return -1;
 
      return 0;
    }
 
    readCount = 0;
 
    while (readCount < 2)
    {
      if (rdg_shall_abort(rdg))
        return -1;
      status =
          rdg_socket_read(rdg->tlsOut->bio, (BYTE*)(&rdg->packetRemainingCount) + readCount,
                          2 - readCount, &rdg->transferEncoding);
 
      if (status < 0)
      {
        if (!BIO_should_retry(rdg->tlsOut->bio))
          return -1;
 
        BIO_wait_read(rdg->tlsOut->bio, 50);
        continue;
      }
 
      readCount += (size_t)status;
    }
  }
 
  readSize = (rdg->packetRemainingCount < size) ? rdg->packetRemainingCount : size;
  status = rdg_socket_read(rdg->tlsOut->bio, buffer, readSize, &rdg->transferEncoding);
 
  if (status <= 0)
  {
    if (!BIO_should_retry(rdg->tlsOut->bio))
    {
      return -1;
    }
 
    return 0;
  }
 
  rdg->packetRemainingCount -= status;
  return status;
}
 
static int rdg_bio_write(BIO* bio, const char* buf, int num)
{
  int status = 0;
  rdpRdg* rdg = (rdpRdg*)BIO_get_data(bio);
  if (num < 0)
    return num;
 
  BIO_clear_flags(bio, BIO_FLAGS_WRITE);
  EnterCriticalSection(&rdg->writeSection);
  status = rdg_write_data_packet(rdg, (const BYTE*)buf, num);
  LeaveCriticalSection(&rdg->writeSection);
 
  if (status < 0)
  {
    BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY);
    return -1;
  }
  else if (status < num)
  {
    BIO_set_flags(bio, BIO_FLAGS_WRITE);
    WSASetLastError(WSAEWOULDBLOCK);
  }
  else
  {
    BIO_set_flags(bio, BIO_FLAGS_WRITE);
  }
 
  return status;
}
 
static int rdg_bio_read(BIO* bio, char* buf, int size)
{
  int status = 0;
  rdpRdg* rdg = (rdpRdg*)BIO_get_data(bio);
  if (size < 0)
    return size;
  status = rdg_read_data_packet(rdg, (BYTE*)buf, (size_t)size);
 
  if (status < 0)
  {
    BIO_clear_retry_flags(bio);
    return -1;
  }
  else if (status == 0)
  {
    BIO_set_retry_read(bio);
    WSASetLastError(WSAEWOULDBLOCK);
    return -1;
  }
  else
  {
    BIO_set_flags(bio, BIO_FLAGS_READ);
  }
 
  return status;
}
 
static int rdg_bio_puts(BIO* bio, const char* str)
{
  WINPR_UNUSED(bio);
  WINPR_UNUSED(str);
  return -2;
}
 
// NOLINTNEXTLINE(readability-non-const-parameter)
static int rdg_bio_gets(BIO* bio, char* str, int size)
{
  WINPR_UNUSED(bio);
  WINPR_UNUSED(str);
  WINPR_UNUSED(size);
  return -2;
}
 
static long rdg_bio_ctrl(BIO* in_bio, int cmd, long arg1, void* arg2)
{
  long status = -1;
  rdpRdg* rdg = (rdpRdg*)BIO_get_data(in_bio);
  rdpTls* tlsOut = rdg->tlsOut;
  rdpTls* tlsIn = rdg->tlsIn;
 
  if (cmd == BIO_CTRL_FLUSH)
  {
    (void)BIO_flush(tlsOut->bio);
    if (!rdg->transferEncoding.isWebsocketTransport)
      (void)BIO_flush(tlsIn->bio);
    status = 1;
  }
  else if (cmd == BIO_C_SET_NONBLOCK)
  {
    status = 1;
  }
  else if (cmd == BIO_C_READ_BLOCKED)
  {
    BIO* cbio = tlsOut->bio;
    status = BIO_read_blocked(cbio);
  }
  else if (cmd == BIO_C_WRITE_BLOCKED)
  {
    BIO* cbio = tlsIn->bio;
 
    if (rdg->transferEncoding.isWebsocketTransport)
      cbio = tlsOut->bio;
 
    status = BIO_write_blocked(cbio);
  }
  else if (cmd == BIO_C_WAIT_READ)
  {
    int timeout = (int)arg1;
    BIO* cbio = tlsOut->bio;
 
    if (BIO_read_blocked(cbio))
      return BIO_wait_read(cbio, timeout);
    else if (BIO_write_blocked(cbio))
      return BIO_wait_write(cbio, timeout);
    else
      status = 1;
  }
  else if (cmd == BIO_C_WAIT_WRITE)
  {
    int timeout = (int)arg1;
    BIO* cbio = tlsIn->bio;
 
    if (rdg->transferEncoding.isWebsocketTransport)
      cbio = tlsOut->bio;
 
    if (BIO_write_blocked(cbio))
      status = BIO_wait_write(cbio, timeout);
    else if (BIO_read_blocked(cbio))
      status = BIO_wait_read(cbio, timeout);
    else
      status = 1;
  }
  else if (cmd == BIO_C_GET_EVENT || cmd == BIO_C_GET_FD)
  {
    /*
     * A note about BIO_C_GET_FD:
     * Even if two FDs are part of RDG, only one FD can be returned here.
     *
     * In FreeRDP, BIO FDs are only used for polling, so it is safe to use the outgoing FD only
     *
     * See issue #3602
     */
    status = BIO_ctrl(tlsOut->bio, cmd, arg1, arg2);
  }
#if OPENSSL_VERSION_NUMBER >= 0x30000000L
  else if (cmd == BIO_CTRL_GET_KTLS_SEND)
  {
    /* Even though BIO_get_ktls_send says that returning negative values is valid
     * openssl internal sources are full of if(!BIO_get_ktls_send && ) stuff. This has some
     * nasty sideeffects. return 0 as proper no KTLS offloading flag
     */
    status = 0;
  }
  else if (cmd == BIO_CTRL_GET_KTLS_RECV)
  {
    /* Even though BIO_get_ktls_recv says that returning negative values is valid
     * there is no reason to trust  trust negative values are implemented right everywhere
     */
    status = 0;
  }
#endif
  return status;
}
 
static int rdg_bio_new(BIO* bio)
{
  BIO_set_init(bio, 1);
  BIO_set_flags(bio, BIO_FLAGS_SHOULD_RETRY);
  return 1;
}
 
static int rdg_bio_free(BIO* bio)
{
  WINPR_UNUSED(bio);
  return 1;
}
 
static BIO_METHOD* BIO_s_rdg(void)
{
  static BIO_METHOD* bio_methods = NULL;
 
  if (bio_methods == NULL)
  {
    if (!(bio_methods = BIO_meth_new(BIO_TYPE_TSG, "RDGateway")))
      return NULL;
 
    BIO_meth_set_write(bio_methods, rdg_bio_write);
    BIO_meth_set_read(bio_methods, rdg_bio_read);
    BIO_meth_set_puts(bio_methods, rdg_bio_puts);
    BIO_meth_set_gets(bio_methods, rdg_bio_gets);
    BIO_meth_set_ctrl(bio_methods, rdg_bio_ctrl);
    BIO_meth_set_create(bio_methods, rdg_bio_new);
    BIO_meth_set_destroy(bio_methods, rdg_bio_free);
  }
 
  return bio_methods;
}
 
rdpRdg* rdg_new(rdpContext* context)
{
  if (!context)
    return NULL;
 
  rdpRdg* rdg = (rdpRdg*)calloc(1, sizeof(rdpRdg));
  if (!rdg)
    return NULL;
 
  rdg->log = WLog_Get(TAG);
  rdg->state = RDG_CLIENT_STATE_INITIAL;
  rdg->context = context;
  rdg->extAuth =
      (rdg->context->settings->GatewayHttpExtAuthSspiNtlm ? HTTP_EXTENDED_AUTH_SSPI_NTLM
                                                          : HTTP_EXTENDED_AUTH_NONE);
 
  if (rdg->context->settings->GatewayAccessToken)
    rdg->extAuth = HTTP_EXTENDED_AUTH_PAA;
 
  UuidCreate(&rdg->guid);
 
  rdg->tlsOut = freerdp_tls_new(rdg->context);
 
  if (!rdg->tlsOut)
    goto rdg_alloc_error;
 
  rdg->tlsIn = freerdp_tls_new(rdg->context);
 
  if (!rdg->tlsIn)
    goto rdg_alloc_error;
 
  rdg->http = http_context_new();
 
  if (!rdg->http)
    goto rdg_alloc_error;
 
  if (!http_context_set_uri(rdg->http, "/remoteDesktopGateway/") ||
      !http_context_set_accept(rdg->http, "*/*") ||
      !http_context_set_cache_control(rdg->http, "no-cache") ||
      !http_context_set_pragma(rdg->http, "no-cache") ||
      !http_context_set_connection(rdg->http, "Keep-Alive") ||
      !http_context_set_user_agent(rdg->http, "MS-RDGateway/1.0") ||
      !http_context_set_host(rdg->http, rdg->context->settings->GatewayHostname) ||
      !http_context_set_rdg_connection_id(rdg->http, &rdg->guid) ||
      !http_context_set_rdg_correlation_id(rdg->http, &rdg->guid) ||
      !http_context_enable_websocket_upgrade(
          rdg->http,
          freerdp_settings_get_bool(rdg->context->settings, FreeRDP_GatewayHttpUseWebsockets)))
  {
    goto rdg_alloc_error;
  }
 
  if (rdg->extAuth != HTTP_EXTENDED_AUTH_NONE)
  {
    switch (rdg->extAuth)
    {
      case HTTP_EXTENDED_AUTH_PAA:
        if (!http_context_set_rdg_auth_scheme(rdg->http, "PAA"))
          goto rdg_alloc_error;
 
        break;
 
      case HTTP_EXTENDED_AUTH_SSPI_NTLM:
        if (!http_context_set_rdg_auth_scheme(rdg->http, "SSPI_NTLM"))
          goto rdg_alloc_error;
 
        break;
 
      default:
        WLog_Print(rdg->log, WLOG_DEBUG,
                   "RDG extended authentication method %d not supported", rdg->extAuth);
    }
  }
 
  rdg->frontBio = BIO_new(BIO_s_rdg());
 
  if (!rdg->frontBio)
    goto rdg_alloc_error;
 
  BIO_set_data(rdg->frontBio, rdg);
  InitializeCriticalSection(&rdg->writeSection);
 
  rdg->transferEncoding.httpTransferEncoding = TransferEncodingIdentity;
  rdg->transferEncoding.isWebsocketTransport = FALSE;
 
  rdg->transferEncoding.context.websocket = websocket_context_new();
  if (!rdg->transferEncoding.context.websocket)
    goto rdg_alloc_error;
 
  return rdg;
rdg_alloc_error:
  WINPR_PRAGMA_DIAG_PUSH
  WINPR_PRAGMA_DIAG_IGNORED_MISMATCHED_DEALLOC
  rdg_free(rdg);
  WINPR_PRAGMA_DIAG_POP
  return NULL;
}
 
void rdg_free(rdpRdg* rdg)
{
  if (!rdg)
    return;
 
  freerdp_tls_free(rdg->tlsOut);
  freerdp_tls_free(rdg->tlsIn);
  http_context_free(rdg->http);
  credssp_auth_free(rdg->auth);
 
  if (!rdg->attached)
    BIO_free_all(rdg->frontBio);
 
  DeleteCriticalSection(&rdg->writeSection);
 
  smartcardCertInfo_Free(rdg->smartcard);
 
  websocket_context_free(rdg->transferEncoding.context.websocket);
 
  free(rdg);
}
 
BIO* rdg_get_front_bio_and_take_ownership(rdpRdg* rdg)
{
  if (!rdg)
    return NULL;
 
  rdg->attached = TRUE;
  return rdg->frontBio;
}