arm.c

 
#include <freerdp/config.h>
#include <freerdp/version.h>
 
#include "../settings.h"
 
#include <winpr/assert.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 <winpr/bcrypt.h>
 
#include <freerdp/log.h>
#include <freerdp/error.h>
#include <freerdp/crypto/certificate.h>
#include <freerdp/utils/ringbuffer.h>
#include <freerdp/utils/smartcardlogon.h>
#include <freerdp/utils/aad.h>
 
#include "arm.h"
#include "wst.h"
#include "websocket.h"
#include "http.h"
#include "../credssp_auth.h"
#include "../proxy.h"
#include "../rdp.h"
#include "../../crypto/crypto.h"
#include "../../crypto/certificate.h"
#include "../../crypto/opensslcompat.h"
#include "rpc_fault.h"
#include "../utils.h"
#include "../redirection.h"
 
#include <winpr/json.h>
 
#include <string.h>
 
struct rdp_arm
{
  rdpContext* context;
  rdpTls* tls;
  HttpContext* http;
 
  UINT32 gateway_retry;
  wLog* log;
};
 
typedef struct rdp_arm rdpArm;
 
#define TAG FREERDP_TAG("core.gateway.arm")
 
#ifdef WITH_AAD
static BOOL arm_tls_connect(rdpArm* arm, rdpTls* tls, UINT32 timeout)
{
  WINPR_ASSERT(arm);
  WINPR_ASSERT(tls);
  int sockfd = 0;
  long status = 0;
  BIO* socketBio = nullptr;
  BIO* bufferedBio = nullptr;
  rdpSettings* settings = arm->context->settings;
  if (!settings)
    return FALSE;
 
  const char* peerHostname = freerdp_settings_get_string(settings, FreeRDP_GatewayHostname);
  if (!peerHostname)
    return FALSE;
 
  UINT16 peerPort = (UINT16)freerdp_settings_get_uint32(settings, FreeRDP_GatewayPort);
  const char* proxyUsername = nullptr;
  const char* proxyPassword = nullptr;
  BOOL isProxyConnection =
      proxy_prepare(settings, &peerHostname, &peerPort, &proxyUsername, &proxyPassword);
 
  sockfd = freerdp_tcp_connect(arm->context, peerHostname, peerPort, timeout);
 
  WLog_Print(arm->log, WLOG_DEBUG, "connecting to %s %d", peerHostname, peerPort);
  if (sockfd < 0)
    return FALSE;
 
  socketBio = BIO_new(BIO_s_simple_socket());
 
  if (!socketBio)
  {
    closesocket((SOCKET)sockfd);
    return FALSE;
  }
 
  BIO_set_fd(socketBio, sockfd, BIO_CLOSE);
  bufferedBio = BIO_new(BIO_s_buffered_socket());
 
  if (!bufferedBio)
  {
    BIO_free_all(socketBio);
    return FALSE;
  }
 
  bufferedBio = BIO_push(bufferedBio, socketBio);
  if (!bufferedBio)
    return FALSE;
 
  status = BIO_set_nonblock(bufferedBio, TRUE);
 
  if (isProxyConnection)
  {
    if (!proxy_connect(arm->context, bufferedBio, proxyUsername, proxyPassword,
                       freerdp_settings_get_string(settings, FreeRDP_GatewayHostname),
                       (UINT16)freerdp_settings_get_uint32(settings, FreeRDP_GatewayPort)))
    {
      BIO_free_all(bufferedBio);
      return FALSE;
    }
  }
 
  if (!status)
  {
    BIO_free_all(bufferedBio);
    return FALSE;
  }
 
  tls->hostname = freerdp_settings_get_string(settings, FreeRDP_GatewayHostname);
  tls->port = MIN(UINT16_MAX, WINPR_ASSERTING_INT_CAST(int32_t, settings->GatewayPort));
  tls->isGatewayTransport = TRUE;
  status = freerdp_tls_connect(tls, bufferedBio);
  if (status < 1)
  {
    rdpContext* context = arm->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 arm_fetch_wellknown(rdpArm* arm)
{
  WINPR_ASSERT(arm);
  WINPR_ASSERT(arm->context);
  WINPR_ASSERT(arm->context->rdp);
 
  rdpRdp* rdp = arm->context->rdp;
  if (rdp->wellknown)
    return TRUE;
 
  const char* base =
      freerdp_settings_get_string(arm->context->settings, FreeRDP_GatewayAzureActiveDirectory);
  const BOOL useTenant =
      freerdp_settings_get_bool(arm->context->settings, FreeRDP_GatewayAvdUseTenantid);
  const char* tenantid = "common";
  if (useTenant)
    tenantid =
        freerdp_settings_get_string(arm->context->settings, FreeRDP_GatewayAvdAadtenantid);
 
  rdp->wellknown = freerdp_utils_aad_get_wellknown(arm->log, base, tenantid);
  return (rdp->wellknown != nullptr);
}
 
static wStream* arm_build_http_request(rdpArm* arm, const char* method,
                                       TRANSFER_ENCODING transferEncoding, const char* content_type,
                                       size_t content_length)
{
  wStream* s = nullptr;
 
  WINPR_ASSERT(arm);
  WINPR_ASSERT(method);
  WINPR_ASSERT(content_type);
 
  WINPR_ASSERT(arm->context);
  WINPR_ASSERT(arm->context->rdp);
 
  const char* uri = http_context_get_uri(arm->http);
  HttpRequest* request = http_request_new();
 
  if (!request)
    return nullptr;
 
  rdpSettings* settings = arm->context->settings;
 
  if (!http_request_set_method(request, method) || !http_request_set_uri(request, uri))
    goto out;
 
  if (!freerdp_settings_get_string(settings, FreeRDP_GatewayHttpExtAuthBearer))
  {
    char* token = nullptr;
 
    pGetCommonAccessToken GetCommonAccessToken = freerdp_get_common_access_token(arm->context);
    if (!GetCommonAccessToken)
    {
      WLog_Print(arm->log, WLOG_ERROR, "No authorization token provided");
      goto out;
    }
 
    if (!arm_fetch_wellknown(arm))
      goto out;
 
    if (!GetCommonAccessToken(arm->context, ACCESS_TOKEN_TYPE_AVD, &token, 0))
    {
      WLog_Print(arm->log, WLOG_ERROR, "Unable to obtain access token");
      goto out;
    }
 
    if (!freerdp_settings_set_string(settings, FreeRDP_GatewayHttpExtAuthBearer, token))
    {
      free(token);
      goto out;
    }
    free(token);
  }
 
  if (!http_request_set_auth_scheme(request, "Bearer") ||
      !http_request_set_auth_param(
          request, freerdp_settings_get_string(settings, FreeRDP_GatewayHttpExtAuthBearer)))
    goto out;
 
  if (!http_request_set_transfer_encoding(request, transferEncoding) ||
      !http_request_set_content_length(request, content_length) ||
      !http_request_set_content_type(request, content_type))
    goto out;
 
  s = http_request_write(arm->http, request);
out:
  http_request_free(request);
 
  if (s)
    Stream_SealLength(s);
 
  return s;
}
 
static BOOL arm_send_http_request(rdpArm* arm, rdpTls* tls, const char* method,
                                  const char* content_type, const char* data, size_t content_length)
{
  int status = -1;
  wStream* s =
      arm_build_http_request(arm, method, TransferEncodingIdentity, content_type, content_length);
 
  if (!s)
    return FALSE;
 
  const size_t sz = Stream_Length(s);
  WLog_Print(arm->log, WLOG_TRACE, "header [%" PRIuz "]: %s", sz, Stream_Buffer(s));
  WLog_Print(arm->log, WLOG_TRACE, "body   [%" PRIuz "]: %s", content_length, data);
  status = freerdp_tls_write_all(tls, Stream_Buffer(s), sz);
 
  Stream_Free(s, TRUE);
  if (status >= 0 && content_length > 0 && data)
    status = freerdp_tls_write_all(tls, (const BYTE*)data, content_length);
 
  return (status >= 0);
}
 
static void arm_free(rdpArm* arm)
{
  if (!arm)
    return;
 
  freerdp_tls_free(arm->tls);
  http_context_free(arm->http);
 
  free(arm);
}
 
static rdpArm* arm_new(rdpContext* context)
{
  WINPR_ASSERT(context);
 
  rdpArm* arm = (rdpArm*)calloc(1, sizeof(rdpArm));
  if (!arm)
    goto fail;
 
  arm->log = WLog_Get(TAG);
  arm->context = context;
  arm->tls = freerdp_tls_new(context);
  if (!arm->tls)
    goto fail;
 
  arm->http = http_context_new();
 
  if (!arm->http)
    goto fail;
 
  return arm;
 
fail:
  arm_free(arm);
  return nullptr;
}
 
static char* arm_create_request_json(rdpArm* arm)
{
  char* lbi = nullptr;
  char* message = nullptr;
 
  WINPR_ASSERT(arm);
 
  WINPR_JSON* json = WINPR_JSON_CreateObject();
  if (!json)
    goto arm_create_cleanup;
  if (!WINPR_JSON_AddStringToObject(
          json, "application",
          freerdp_settings_get_string(arm->context->settings, FreeRDP_RemoteApplicationProgram)))
    goto arm_create_cleanup;
 
  lbi = calloc(
      freerdp_settings_get_uint32(arm->context->settings, FreeRDP_LoadBalanceInfoLength) + 1,
      sizeof(char));
  if (!lbi)
    goto arm_create_cleanup;
 
  {
    const size_t len =
        freerdp_settings_get_uint32(arm->context->settings, FreeRDP_LoadBalanceInfoLength);
    memcpy(lbi, freerdp_settings_get_pointer(arm->context->settings, FreeRDP_LoadBalanceInfo),
           len);
  }
 
  if (!WINPR_JSON_AddStringToObject(json, "loadBalanceInfo", lbi))
    goto arm_create_cleanup;
  if (!WINPR_JSON_AddNullToObject(json, "LogonToken"))
    goto arm_create_cleanup;
  if (!WINPR_JSON_AddNullToObject(json, "gatewayLoadBalancerToken"))
    goto arm_create_cleanup;
 
  message = WINPR_JSON_PrintUnformatted(json);
arm_create_cleanup:
  if (json)
    WINPR_JSON_Delete(json);
  free(lbi);
  return message;
}
 
static WINPR_CIPHER_CTX* treatAuthBlob(wLog* log, const BYTE* pbInput, size_t cbInput,
                                       size_t* pBlockSize)
{
  WINPR_CIPHER_CTX* ret = nullptr;
  char algoName[100] = WINPR_C_ARRAY_INIT;
 
  WINPR_ASSERT(pBlockSize);
  SSIZE_T algoSz = ConvertWCharNToUtf8((const WCHAR*)pbInput, cbInput / sizeof(WCHAR), algoName,
                                       sizeof(algoName) - 1);
  if (algoSz <= 0)
  {
    WLog_Print(log, WLOG_ERROR, "invalid algoName");
    return nullptr;
  }
 
  if (strcmp(algoName, "AES") != 0)
  {
    WLog_Print(log, WLOG_ERROR, "only AES is supported for now");
    return nullptr;
  }
 
  *pBlockSize = WINPR_AES_BLOCK_SIZE;
  const size_t algoLen = WINPR_ASSERTING_INT_CAST(size_t, (algoSz + 1)) * sizeof(WCHAR);
  if (cbInput < algoLen)
  {
    WLog_Print(log, WLOG_ERROR, "invalid AuthBlob size");
    return nullptr;
  }
 
  cbInput -= algoLen;
 
  /* BCRYPT_KEY_DATA_BLOB_HEADER */
  wStream staticStream = WINPR_C_ARRAY_INIT;
  wStream* s = Stream_StaticConstInit(&staticStream, &pbInput[algoLen], cbInput);
 
  if (!Stream_CheckAndLogRequiredLengthWLog(log, s, 12))
    return nullptr;
 
  const UINT32 dwMagic = Stream_Get_UINT32(s);
  if (dwMagic != BCRYPT_KEY_DATA_BLOB_MAGIC)
  {
    WLog_Print(log, WLOG_ERROR, "unsupported authBlob type");
    return nullptr;
  }
 
  const UINT32 dwVersion = Stream_Get_UINT32(s);
  if (dwVersion != BCRYPT_KEY_DATA_BLOB_VERSION1)
  {
    WLog_Print(log, WLOG_ERROR, "unsupported authBlob version %" PRIu32 ", expecting %d",
               dwVersion, BCRYPT_KEY_DATA_BLOB_VERSION1);
    return nullptr;
  }
 
  const UINT32 cbKeyData = Stream_Get_UINT32(s);
  if (!Stream_CheckAndLogRequiredLengthWLog(log, s, cbKeyData))
  {
    WLog_Print(log, WLOG_ERROR, "invalid authBlob size");
    return nullptr;
  }
 
  WINPR_CIPHER_TYPE cipherType = WINPR_CIPHER_NONE;
  switch (cbKeyData)
  {
    case 16:
      cipherType = WINPR_CIPHER_AES_128_CBC;
      break;
    case 24:
      cipherType = WINPR_CIPHER_AES_192_CBC;
      break;
    case 32:
      cipherType = WINPR_CIPHER_AES_256_CBC;
      break;
    default:
      WLog_Print(log, WLOG_ERROR, "invalid authBlob cipher size");
      return nullptr;
  }
 
  ret = winpr_Cipher_NewEx(cipherType, WINPR_ENCRYPT, Stream_Pointer(s), cbKeyData, nullptr, 0);
  if (!ret)
  {
    WLog_Print(log, WLOG_ERROR, "error creating cipher");
    return nullptr;
  }
 
  if (!winpr_Cipher_SetPadding(ret, TRUE))
  {
    WLog_Print(log, WLOG_ERROR, "unable to enable padding on cipher");
    winpr_Cipher_Free(ret);
    return nullptr;
  }
 
  return ret;
}
 
static BOOL arm_stringEncodeW(const BYTE* pin, size_t cbIn, BYTE** ppOut, size_t* pcbOut)
{
  *ppOut = nullptr;
  *pcbOut = 0;
 
  /* encode to base64 with crlf */
  char* b64encoded = crypto_base64_encode_ex(pin, cbIn, TRUE);
  if (!b64encoded)
    return FALSE;
 
  /* and then convert to Unicode */
  size_t outSz = 0;
  *ppOut = (BYTE*)ConvertUtf8NToWCharAlloc(b64encoded, strlen(b64encoded), &outSz);
  free(b64encoded);
 
  if (!*ppOut)
    return FALSE;
 
  *pcbOut = (outSz + 1) * sizeof(WCHAR);
  return TRUE;
}
 
static BOOL arm_encodeRedirectPasswd(wLog* log, rdpSettings* settings, const rdpCertificate* cert,
                                     WINPR_CIPHER_CTX* cipher, size_t blockSize)
{
  BOOL ret = FALSE;
  BYTE* output = nullptr;
  BYTE* finalOutput = nullptr;
 
  /* let's prepare the encrypted password, first we do a
   *    cipheredPass = AES(redirectedAuthBlob, toUtf16(passwd))
   */
 
  size_t wpasswdLen = 0;
  WCHAR* wpasswd = freerdp_settings_get_string_as_utf16(settings, FreeRDP_Password, &wpasswdLen);
  if (!wpasswd)
  {
    WLog_Print(log, WLOG_ERROR, "error when converting password to UTF16");
    return FALSE;
  }
 
  const size_t wpasswdBytes = (wpasswdLen + 1) * sizeof(WCHAR);
  BYTE* encryptedPass = calloc(1, wpasswdBytes + blockSize); /* 16: block size of AES (padding) */
 
  if (!encryptedPass)
    goto out;
 
  {
    size_t encryptedPassLen = 0;
    if (!winpr_Cipher_Update(cipher, wpasswd, wpasswdBytes, encryptedPass, &encryptedPassLen))
      goto out;
 
    if (encryptedPassLen > wpasswdBytes)
      goto out;
 
    {
      size_t finalLen = 0;
      if (!winpr_Cipher_Final(cipher, &encryptedPass[encryptedPassLen], &finalLen))
      {
        WLog_Print(log, WLOG_ERROR, "error when ciphering password");
        goto out;
      }
      encryptedPassLen += finalLen;
    }
 
    /* then encrypt(cipheredPass, publicKey(redirectedServerCert) */
    {
      size_t output_length = 0;
      if (!freerdp_certificate_publickey_encrypt(cert, encryptedPass, encryptedPassLen,
                                                 &output, &output_length))
      {
        WLog_Print(log, WLOG_ERROR, "unable to encrypt with the server's public key");
        goto out;
      }
 
      {
        size_t finalOutputLen = 0;
        if (!arm_stringEncodeW(output, output_length, &finalOutput, &finalOutputLen))
        {
          WLog_Print(log, WLOG_ERROR, "unable to base64+utf16 final blob");
          goto out;
        }
 
        if (!freerdp_settings_set_pointer_len(settings, FreeRDP_RedirectionPassword,
                                              finalOutput, finalOutputLen))
        {
          WLog_Print(log, WLOG_ERROR,
                     "unable to set the redirection password in settings");
          goto out;
        }
      }
    }
  }
 
  settings->RdstlsSecurity = TRUE;
  settings->AadSecurity = FALSE;
  settings->NlaSecurity = FALSE;
  settings->RdpSecurity = FALSE;
  settings->TlsSecurity = FALSE;
  settings->RedirectionFlags = LB_PASSWORD_IS_PK_ENCRYPTED;
  ret = TRUE;
out:
  free(finalOutput);
  free(output);
  free(encryptedPass);
  free(wpasswd);
  return ret;
}
 
static BOOL arm_pick_base64Utf16Field(wLog* log, const WINPR_JSON* json, const char* name,
                                      BYTE** poutput, size_t* plen)
{
  *poutput = nullptr;
  *plen = 0;
 
  WINPR_JSON* node = WINPR_JSON_GetObjectItemCaseSensitive(json, name);
  if (!node || !WINPR_JSON_IsString(node))
    return TRUE;
 
  const char* nodeValue = WINPR_JSON_GetStringValue(node);
  if (!nodeValue)
    return TRUE;
 
  BYTE* output1 = nullptr;
  size_t len1 = 0;
  crypto_base64_decode(nodeValue, strlen(nodeValue), &output1, &len1);
  if (!output1 || !len1)
  {
    WLog_Print(log, WLOG_ERROR, "error when first unbase64 for %s", name);
    free(output1);
    return FALSE;
  }
 
  size_t len2 = 0;
  char* output2 = ConvertWCharNToUtf8Alloc((WCHAR*)output1, len1 / sizeof(WCHAR), &len2);
  free(output1);
  if (!output2 || !len2)
  {
    WLog_Print(log, WLOG_ERROR, "error when decode('utf-16') for %s", name);
    free(output2);
    return FALSE;
  }
 
  BYTE* output = nullptr;
  crypto_base64_decode(output2, len2, &output, plen);
  free(output2);
  if (!output || !*plen)
  {
    WLog_Print(log, WLOG_ERROR, "error when second unbase64 for %s", name);
    free(output);
    return FALSE;
  }
 
  *poutput = output;
  return TRUE;
}
 
static size_t arm_parse_ipvx_count(WINPR_JSON* ipvX)
{
  WINPR_ASSERT(ipvX);
  WINPR_JSON* ipAddress = WINPR_JSON_GetObjectItemCaseSensitive(ipvX, "ipAddress");
  if (!ipAddress || !WINPR_JSON_IsArray(ipAddress))
    return 0;
 
  /* Each entry might contain a public and a private address */
  return WINPR_JSON_GetArraySize(ipAddress) * 2;
}
 
static BOOL arm_parse_ipv6(rdpSettings* settings, WINPR_JSON* ipv6, size_t* pAddressIdx)
{
  WINPR_ASSERT(settings);
  WINPR_ASSERT(ipv6);
  WINPR_ASSERT(pAddressIdx);
 
  if (!freerdp_settings_get_bool(settings, FreeRDP_IPv6Enabled))
    return TRUE;
 
  WINPR_JSON* ipAddress = WINPR_JSON_GetObjectItemCaseSensitive(ipv6, "ipAddress");
  if (!ipAddress || !WINPR_JSON_IsArray(ipAddress))
    return TRUE;
  const size_t naddresses = WINPR_JSON_GetArraySize(ipAddress);
  const uint32_t count = freerdp_settings_get_uint32(settings, FreeRDP_TargetNetAddressCount);
  for (size_t j = 0; j < naddresses; j++)
  {
    WINPR_JSON* adressN = WINPR_JSON_GetArrayItem(ipAddress, j);
    if (!adressN || !WINPR_JSON_IsString(adressN))
      continue;
 
    const char* addr = WINPR_JSON_GetStringValue(adressN);
    if (utils_str_is_empty(addr))
      continue;
 
    if (*pAddressIdx >= count)
    {
      WLog_ERR(TAG, "Exceeded TargetNetAddresses, parsing failed");
      return FALSE;
    }
 
    if (!winpr_str_is_valid_url(addr))
      return FALSE;
 
    if (!freerdp_settings_set_pointer_array(settings, FreeRDP_TargetNetAddresses,
                                            (*pAddressIdx)++, addr))
      return FALSE;
  }
  return TRUE;
}
 
static BOOL arm_parse_ipv4(rdpSettings* settings, WINPR_JSON* ipv4, size_t* pAddressIdx)
{
  WINPR_ASSERT(settings);
  WINPR_ASSERT(ipv4);
  WINPR_ASSERT(pAddressIdx);
 
  WINPR_JSON* ipAddress = WINPR_JSON_GetObjectItemCaseSensitive(ipv4, "ipAddress");
  if (!ipAddress || !WINPR_JSON_IsArray(ipAddress))
    return TRUE;
 
  const size_t naddresses = WINPR_JSON_GetArraySize(ipAddress);
  const uint32_t count = freerdp_settings_get_uint32(settings, FreeRDP_TargetNetAddressCount);
  for (size_t j = 0; j < naddresses; j++)
  {
    WINPR_JSON* adressN = WINPR_JSON_GetArrayItem(ipAddress, j);
    if (!adressN)
      continue;
 
    WINPR_JSON* publicIpNode =
        WINPR_JSON_GetObjectItemCaseSensitive(adressN, "publicIpAddress");
    if (publicIpNode && WINPR_JSON_IsString(publicIpNode))
    {
      const char* publicIp = WINPR_JSON_GetStringValue(publicIpNode);
      if (!utils_str_is_empty(publicIp))
      {
        if (*pAddressIdx >= count)
        {
          WLog_ERR(TAG, "Exceeded TargetNetAddresses, parsing failed");
          return FALSE;
        }
 
        if (!utils_is_valid_ip(publicIp))
          return FALSE;
 
        if (!freerdp_settings_set_pointer_array(settings, FreeRDP_TargetNetAddresses,
                                                (*pAddressIdx)++, publicIp))
          return FALSE;
      }
    }
 
    WINPR_JSON* privateIpNode =
        WINPR_JSON_GetObjectItemCaseSensitive(adressN, "privateIpAddress");
    if (privateIpNode && WINPR_JSON_IsString(privateIpNode))
    {
      const char* privateIp = WINPR_JSON_GetStringValue(privateIpNode);
      if (!utils_str_is_empty(privateIp))
      {
        if (*pAddressIdx >= count)
        {
          WLog_ERR(TAG, "Exceeded TargetNetAddresses, parsing failed");
          return FALSE;
        }
        if (!utils_is_valid_ip(privateIp))
          return FALSE;
 
        if (!freerdp_settings_set_pointer_array(settings, FreeRDP_TargetNetAddresses,
                                                (*pAddressIdx)++, privateIp))
          return FALSE;
      }
    }
  }
  return TRUE;
}
 
static BOOL arm_treat_azureInstanceNetworkMetadata(wLog* log, const char* metadata,
                                                   rdpSettings* settings)
{
  BOOL ret = FALSE;
 
  WINPR_ASSERT(settings);
 
  if (!freerdp_target_net_adresses_reset(settings, 0))
    return FALSE;
 
  WINPR_JSON* json = WINPR_JSON_Parse(metadata);
  if (!json)
  {
    WLog_Print(log, WLOG_ERROR, "invalid azureInstanceNetworkMetadata");
    return FALSE;
  }
 
  WINPR_JSON* iface = WINPR_JSON_GetObjectItemCaseSensitive(json, "interface");
  if (!iface)
  {
    ret = TRUE;
    goto out;
  }
 
  if (!WINPR_JSON_IsArray(iface))
  {
    WLog_Print(log, WLOG_ERROR, "expecting interface to be an Array");
    goto out;
  }
 
  {
    const size_t interfaceSz = WINPR_JSON_GetArraySize(iface);
    if (interfaceSz == 0)
    {
      WLog_WARN(TAG, "no addresses in azure instance metadata");
      ret = TRUE;
      goto out;
    }
 
    {
      size_t count = 0;
      for (size_t i = 0; i < interfaceSz; i++)
      {
        WINPR_JSON* interN = WINPR_JSON_GetArrayItem(iface, i);
        if (!interN)
          continue;
 
        WINPR_JSON* ipv6 = WINPR_JSON_GetObjectItemCaseSensitive(interN, "ipv6");
        if (ipv6)
          count += arm_parse_ipvx_count(ipv6);
 
        WINPR_JSON* ipv4 = WINPR_JSON_GetObjectItemCaseSensitive(interN, "ipv4");
        if (ipv4)
          count += arm_parse_ipvx_count(ipv4);
      }
 
      if (!freerdp_target_net_adresses_reset(settings, count))
        return FALSE;
    }
 
    {
      size_t addressIdx = 0;
      for (size_t i = 0; i < interfaceSz; i++)
      {
        WINPR_JSON* interN = WINPR_JSON_GetArrayItem(iface, i);
        if (!interN)
          continue;
 
        WINPR_JSON* ipv6 = WINPR_JSON_GetObjectItemCaseSensitive(interN, "ipv6");
        if (ipv6)
        {
          if (!arm_parse_ipv6(settings, ipv6, &addressIdx))
            goto out;
        }
 
        WINPR_JSON* ipv4 = WINPR_JSON_GetObjectItemCaseSensitive(interN, "ipv4");
        if (ipv4)
        {
          if (!arm_parse_ipv4(settings, ipv4, &addressIdx))
            goto out;
        }
      }
      if (addressIdx > UINT32_MAX)
        goto out;
 
      if (!freerdp_settings_set_uint32(settings, FreeRDP_TargetNetAddressCount,
                                       (UINT32)addressIdx))
        goto out;
 
      ret = addressIdx > 0;
    }
  }
 
out:
  WINPR_JSON_Delete(json);
  return ret;
}
 
static void zfree(char* str)
{
  if (str)
  {
    char* cur = str;
    while (*cur != '\0')
      *cur++ = '\0';
  }
  free(str);
}
 
static BOOL arm_fill_rdstls(rdpArm* arm, rdpSettings* settings, const WINPR_JSON* json,
                            const rdpCertificate* redirectedServerCert)
{
  WINPR_ASSERT(arm);
  BOOL ret = FALSE;
  BYTE* authBlob = nullptr;
  WCHAR* wGUID = nullptr;
 
  const char* redirUser = freerdp_settings_get_string(settings, FreeRDP_RedirectionUsername);
  if (redirUser)
  {
    if (!freerdp_settings_set_string(settings, FreeRDP_Username, redirUser))
      goto end;
  }
 
  /* Azure/Entra requires the domain field to be set to 'AzureAD' in most cases.
   * Some setups have been reported to require a different one, so only supply the suggested
   * default if there was no other domain provided.
   */
  {
    const char* redirDomain = freerdp_settings_get_string(settings, FreeRDP_Domain);
    if (!redirDomain)
    {
      if (!freerdp_settings_set_string(settings, FreeRDP_Domain, "AzureAD"))
        goto end;
    }
  }
 
  {
    const char* duser = freerdp_settings_get_string(settings, FreeRDP_Username);
    const char* ddomain = freerdp_settings_get_string(settings, FreeRDP_Domain);
    const char* dpwd = freerdp_settings_get_string(settings, FreeRDP_Password);
    if (!duser || !dpwd)
    {
      WINPR_ASSERT(arm->context);
      WINPR_ASSERT(arm->context->instance);
 
      char* username = nullptr;
      char* password = nullptr;
      char* domain = nullptr;
 
      if (ddomain)
        domain = _strdup(ddomain);
      if (duser)
        username = _strdup(duser);
 
      const BOOL rc =
          IFCALLRESULT(FALSE, arm->context->instance->AuthenticateEx, arm->context->instance,
                       &username, &password, &domain, AUTH_RDSTLS);
 
      const BOOL rc1 = freerdp_settings_set_string(settings, FreeRDP_Username, username);
      const BOOL rc2 = freerdp_settings_set_string(settings, FreeRDP_Password, password);
      const BOOL rc3 = freerdp_settings_set_string(settings, FreeRDP_Domain, domain);
      zfree(username);
      zfree(password);
      zfree(domain);
      if (!rc || !rc1 || !rc2 || !rc3)
        goto end;
    }
  }
 
  /* redirectedAuthGuid */
  {
    WINPR_JSON* redirectedAuthGuidNode =
        WINPR_JSON_GetObjectItemCaseSensitive(json, "redirectedAuthGuid");
    if (!redirectedAuthGuidNode || !WINPR_JSON_IsString(redirectedAuthGuidNode))
      goto end;
 
    {
      const char* redirectedAuthGuid = WINPR_JSON_GetStringValue(redirectedAuthGuidNode);
      if (!redirectedAuthGuid)
        goto end;
 
      {
        size_t wGUID_len = 0;
        wGUID = ConvertUtf8ToWCharAlloc(redirectedAuthGuid, &wGUID_len);
        if (!wGUID || (wGUID_len == 0))
        {
          WLog_Print(arm->log, WLOG_ERROR,
                     "unable to allocate space for redirectedAuthGuid");
          goto end;
        }
 
        {
          const BOOL status = freerdp_settings_set_pointer_len(
              settings, FreeRDP_RedirectionGuid, wGUID, (wGUID_len + 1) * sizeof(WCHAR));
 
          if (!status)
          {
            WLog_Print(arm->log, WLOG_ERROR, "unable to set RedirectionGuid");
            goto end;
          }
        }
      }
    }
  }
 
  /* redirectedAuthBlob */
  {
    size_t authBlobLen = 0;
    if (!arm_pick_base64Utf16Field(arm->log, json, "redirectedAuthBlob", &authBlob,
                                   &authBlobLen))
      goto end;
 
    {
      size_t blockSize = 0;
      WINPR_CIPHER_CTX* cipher = treatAuthBlob(arm->log, authBlob, authBlobLen, &blockSize);
      if (!cipher)
        goto end;
 
      {
        const BOOL rerp = arm_encodeRedirectPasswd(arm->log, settings, redirectedServerCert,
                                                   cipher, blockSize);
        winpr_Cipher_Free(cipher);
        if (!rerp)
          goto end;
      }
    }
  }
 
  ret = TRUE;
 
end:
  free(wGUID);
  free(authBlob);
  return ret;
}
 
static BOOL arm_fill_gateway_parameters(rdpArm* arm, const char* message, size_t len)
{
  WINPR_ASSERT(arm);
  WINPR_ASSERT(arm->context);
  WINPR_ASSERT(message);
 
  rdpCertificate* redirectedServerCert = nullptr;
  WINPR_JSON* json = WINPR_JSON_ParseWithLength(message, len);
  BOOL status = FALSE;
  if (!json)
  {
    WLog_Print(arm->log, WLOG_ERROR, "Response data is not valid JSON: %s",
               WINPR_JSON_GetErrorPtr());
    return FALSE;
  }
 
  if (WLog_IsLevelActive(arm->log, WLOG_DEBUG))
  {
    char* str = WINPR_JSON_PrintUnformatted(json);
    WLog_Print(arm->log, WLOG_DEBUG, "Got HTTP Response data: %s", str);
    free(str);
  }
 
  rdpSettings* settings = arm->context->settings;
  WINPR_JSON* gwurl = WINPR_JSON_GetObjectItemCaseSensitive(json, "gatewayLocationPreWebSocket");
  if (!gwurl)
    gwurl = WINPR_JSON_GetObjectItemCaseSensitive(json, "gatewayLocation");
  const char* gwurlstr = WINPR_JSON_GetStringValue(gwurl);
  if (gwurlstr != nullptr)
  {
    WLog_Print(arm->log, WLOG_DEBUG, "extracted target url %s", gwurlstr);
    if (!freerdp_settings_set_string(settings, FreeRDP_GatewayUrl, gwurlstr))
      goto fail;
  }
 
  {
    WINPR_JSON* serverNameNode =
        WINPR_JSON_GetObjectItemCaseSensitive(json, "redirectedServerName");
    if (serverNameNode)
    {
      const char* serverName = WINPR_JSON_GetStringValue(serverNameNode);
      if (serverName)
      {
        if (!freerdp_settings_set_string(settings, FreeRDP_ServerHostname, serverName))
          goto fail;
      }
    }
  }
 
  {
    const char key[] = "redirectedUsername";
    if (WINPR_JSON_HasObjectItem(json, key))
    {
      const char* userName = nullptr;
      WINPR_JSON* userNameNode = WINPR_JSON_GetObjectItemCaseSensitive(json, key);
      if (userNameNode)
        userName = WINPR_JSON_GetStringValue(userNameNode);
      if (!freerdp_settings_set_string(settings, FreeRDP_RedirectionUsername, userName))
        goto fail;
    }
  }
 
  {
    WINPR_JSON* azureMeta =
        WINPR_JSON_GetObjectItemCaseSensitive(json, "azureInstanceNetworkMetadata");
    if (azureMeta && WINPR_JSON_IsString(azureMeta))
    {
      if (!arm_treat_azureInstanceNetworkMetadata(
              arm->log, WINPR_JSON_GetStringValue(azureMeta), settings))
      {
        WLog_Print(arm->log, WLOG_ERROR,
                   "error when treating azureInstanceNetworkMetadata");
        goto fail;
      }
    }
  }
 
  /* redirectedServerCert */
  {
    size_t certLen = 0;
    BYTE* cert = nullptr;
    if (arm_pick_base64Utf16Field(arm->log, json, "redirectedServerCert", &cert, &certLen))
    {
      const BOOL rc = rdp_redirection_read_target_cert(&redirectedServerCert, cert, certLen);
      free(cert);
      if (!rc)
        goto fail;
      else if (!rdp_set_target_certificate(settings, redirectedServerCert))
        goto fail;
    }
  }
 
  if (freerdp_settings_get_bool(settings, FreeRDP_AadSecurity))
    status = TRUE;
  else
    status = arm_fill_rdstls(arm, settings, json, redirectedServerCert);
 
fail:
  WINPR_JSON_Delete(json);
  freerdp_certificate_free(redirectedServerCert);
  return status;
}
 
static BOOL arm_handle_request_ok(rdpArm* arm, const HttpResponse* response)
{
  const size_t len = http_response_get_body_length(response);
  const char* msg = http_response_get_body(response);
  const size_t alen = strnlen(msg, len + 1);
  if (alen > len)
  {
    WLog_Print(arm->log, WLOG_ERROR, "Got HTTP Response data with invalid termination");
    return FALSE;
  }
 
  return arm_fill_gateway_parameters(arm, msg, len);
}
 
static BOOL arm_handle_bad_request(rdpArm* arm, const HttpResponse* response, BOOL* retry)
{
  WINPR_ASSERT(response);
  WINPR_ASSERT(retry);
 
  *retry = FALSE;
 
  BOOL rc = FALSE;
 
  http_response_log_error_status(WLog_Get(TAG), WLOG_ERROR, response);
 
  const size_t len = http_response_get_body_length(response);
  const char* msg = http_response_get_body(response);
  if (msg && (strnlen(msg, len + 1) > len))
  {
    WLog_Print(arm->log, WLOG_ERROR, "Got HTTP Response data, but length is invalid");
 
    return FALSE;
  }
 
  WLog_Print(arm->log, WLOG_DEBUG, "Got HTTP Response data: %s", msg);
 
  WINPR_JSON* json = WINPR_JSON_ParseWithLength(msg, len);
  if (json == nullptr)
  {
    const char* error_ptr = WINPR_JSON_GetErrorPtr();
    WLog_Print(arm->log, WLOG_ERROR, "WINPR_JSON_ParseWithLength: %s", error_ptr);
 
    return FALSE;
  }
  else
  {
    WINPR_JSON* gateway_code_obj = WINPR_JSON_GetObjectItemCaseSensitive(json, "Code");
    const char* gw_code_str = WINPR_JSON_GetStringValue(gateway_code_obj);
    if (gw_code_str == nullptr)
    {
      WLog_Print(arm->log, WLOG_ERROR, "Response has no \"Code\" property");
      goto fail;
    }
 
    if (strcmp(gw_code_str, "E_PROXY_ORCHESTRATION_LB_SESSIONHOST_DEALLOCATED") == 0)
    {
      *retry = TRUE;
      WINPR_JSON* message = WINPR_JSON_GetObjectItemCaseSensitive(json, "Message");
      const char* msgstr = WINPR_JSON_GetStringValue(message);
      if (!msgstr)
        WLog_WARN(TAG, "Starting your VM. It may take up to 5 minutes");
      else
        WLog_WARN(TAG, "%s", msgstr);
      freerdp_set_last_error_if_not(arm->context, FREERDP_ERROR_CONNECT_TARGET_BOOTING);
    }
    else
    {
      goto fail;
    }
  }
 
  rc = TRUE;
fail:
  WINPR_JSON_Delete(json);
  return rc;
}
 
static BOOL arm_handle_request(rdpArm* arm, BOOL* retry, DWORD timeout)
{
  WINPR_ASSERT(retry);
 
  if (!arm_fetch_wellknown(arm))
  {
    *retry = TRUE;
    return FALSE;
  }
 
  *retry = FALSE;
 
  char* message = nullptr;
  BOOL rc = FALSE;
 
  HttpResponse* response = nullptr;
  long StatusCode = 0;
 
  const char* useragent =
      freerdp_settings_get_string(arm->context->settings, FreeRDP_GatewayHttpUserAgent);
  const char* msuseragent =
      freerdp_settings_get_string(arm->context->settings, FreeRDP_GatewayHttpMsUserAgent);
  if (!http_context_set_uri(arm->http, "/api/arm/v2/connections") ||
      !http_context_set_accept(arm->http, "*/*") ||
      !http_context_set_cache_control(arm->http, "no-cache") ||
      !http_context_set_pragma(arm->http, "no-cache") ||
      !http_context_set_connection(arm->http, "Keep-Alive") ||
      !http_context_set_user_agent(arm->http, useragent) ||
      !http_context_set_x_ms_user_agent(arm->http, msuseragent) ||
      !http_context_set_host(arm->http, freerdp_settings_get_string(arm->context->settings,
                                                                    FreeRDP_GatewayHostname)))
    goto arm_error;
 
  if (!arm_tls_connect(arm, arm->tls, timeout))
    goto arm_error;
 
  message = arm_create_request_json(arm);
  if (!message)
    goto arm_error;
 
  if (!arm_send_http_request(arm, arm->tls, "POST", "application/json", message, strlen(message)))
    goto arm_error;
 
  response = http_response_recv(arm->tls, TRUE);
  if (!response)
    goto arm_error;
 
  StatusCode = http_response_get_status_code(response);
  if (StatusCode == HTTP_STATUS_OK)
  {
    if (!arm_handle_request_ok(arm, response))
      goto arm_error;
  }
  else if (StatusCode == HTTP_STATUS_BAD_REQUEST)
  {
    if (!arm_handle_bad_request(arm, response, retry))
      goto arm_error;
  }
  else
  {
    http_response_log_error_status(WLog_Get(TAG), WLOG_ERROR, response);
    goto arm_error;
  }
 
  rc = TRUE;
arm_error:
  http_response_free(response);
  free(message);
  return rc;
}
 
#endif
 
BOOL arm_resolve_endpoint(wLog* log, rdpContext* context, DWORD timeout)
{
#ifndef WITH_AAD
  WLog_Print(log, WLOG_ERROR, "arm gateway support not compiled in");
  return FALSE;
#else
 
  if (!context)
    return FALSE;
 
  if (!context->settings)
    return FALSE;
 
  if ((freerdp_settings_get_uint32(context->settings, FreeRDP_LoadBalanceInfoLength) == 0) ||
      (freerdp_settings_get_string(context->settings, FreeRDP_RemoteApplicationProgram) ==
       nullptr))
  {
    WLog_Print(log, WLOG_ERROR, "loadBalanceInfo and RemoteApplicationProgram needed");
    return FALSE;
  }
 
  rdpArm* arm = arm_new(context);
  if (!arm)
    return FALSE;
 
  BOOL retry = FALSE;
  BOOL rc = FALSE;
  do
  {
    if (retry && rc)
    {
      freerdp* instance = context->instance;
      WINPR_ASSERT(instance);
      SSIZE_T delay = IFCALLRESULT(-1, instance->RetryDialog, instance, "arm-transport",
                                   arm->gateway_retry, arm);
      arm->gateway_retry++;
      if (delay <= 0)
        break; /* error or no retry desired, abort loop */
      else
      {
        WLog_Print(arm->log, WLOG_DEBUG, "Delay for %" PRIdz "ms before next attempt",
                   delay);
        while (delay > 0)
        {
          DWORD slp = (UINT32)delay;
          if (delay > UINT32_MAX)
            slp = UINT32_MAX;
          Sleep(slp);
          delay -= slp;
        }
      }
    }
    rc = arm_handle_request(arm, &retry, timeout);
 
  } while (retry && rc);
  arm_free(arm);
  return rc;
#endif
}