/src/FreeRDP/libfreerdp/core/nla.c

Source (jump to first uncovered line)
/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * Network Level Authentication (NLA)
 *
 * Copyright 2010-2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
 * Copyright 2015 Thincast Technologies GmbH
 * Copyright 2015 DI (FH) Martin Haimberger <martin.haimberger@thincast.com>
 * Copyright 2016 Martin Fleisz <martin.fleisz@thincast.com>
 * Copyright 2017 Dorian Ducournau <dorian.ducournau@gmail.com>
 * Copyright 2022 David Fort <contact@hardening-consulting.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <freerdp/config.h>

#include "settings.h"

#include <time.h>
#include <ctype.h>

#include <freerdp/log.h>
#include <freerdp/build-config.h>

#include <winpr/crt.h>
#include <winpr/assert.h>
#include <winpr/sam.h>
#include <winpr/sspi.h>
#include <winpr/print.h>
#include <winpr/tchar.h>
#include <winpr/ncrypt.h>
#include <winpr/cred.h>
#include <winpr/debug.h>
#include <winpr/asn1.h>
#include <winpr/secapi.h>

#include "../crypto/tls.h"
#include "nego.h"
#include "rdp.h"
#include "nla.h"
#include "utils.h"
#include "credssp_auth.h"
#include <freerdp/utils/smartcardlogon.h>

#define TAG FREERDP_TAG("core.nla")

#define SERVER_KEY "Software\\" FREERDP_VENDOR_STRING "\\" FREERDP_PRODUCT_STRING "\\Server"

#define NLA_AUTH_PKG NEGO_SSP_NAME

typedef enum
{
  AUTHZ_SUCCESS = 0x00000000,
  AUTHZ_ACCESS_DENIED = 0x00000005,
} AUTHZ_RESULT;

/**
 * TSRequest ::= SEQUENCE {
 *  version    [0] INTEGER,
 *  negoTokens [1] NegoData OPTIONAL,
 *  authInfo   [2] OCTET STRING OPTIONAL,
 *  pubKeyAuth [3] OCTET STRING OPTIONAL,
 *  errorCode  [4] INTEGER OPTIONAL
 * }
 *
 * NegoData ::= SEQUENCE OF NegoDataItem
 *
 * NegoDataItem ::= SEQUENCE {
 *  negoToken [0] OCTET STRING
 * }
 *
 * TSCredentials ::= SEQUENCE {
 *  credType    [0] INTEGER,
 *  credentials [1] OCTET STRING
 * }
 *
 * TSPasswordCreds ::= SEQUENCE {
 *  domainName  [0] OCTET STRING,
 *  userName    [1] OCTET STRING,
 *  password    [2] OCTET STRING
 * }
 *
 * TSSmartCardCreds ::= SEQUENCE {
 *  pin        [0] OCTET STRING,
 *  cspData    [1] TSCspDataDetail,
 *  userHint   [2] OCTET STRING OPTIONAL,
 *  domainHint [3] OCTET STRING OPTIONAL
 * }
 *
 * TSCspDataDetail ::= SEQUENCE {
 *  keySpec       [0] INTEGER,
 *  cardName      [1] OCTET STRING OPTIONAL,
 *  readerName    [2] OCTET STRING OPTIONAL,
 *  containerName [3] OCTET STRING OPTIONAL,
 *  cspName       [4] OCTET STRING OPTIONAL
 * }
 *
 */

#define NLA_PKG_NAME CREDSSP_AUTH_PKG_SPNEGO

struct rdp_nla
{
  BOOL server;
  NLA_STATE state;
  ULONG sendSeqNum;
  ULONG recvSeqNum;
  rdpContext* rdpcontext;
  rdpTransport* transport;
  UINT32 version;
  UINT32 peerVersion;
  UINT32 errorCode;

  /* Lifetime of buffer nla_new -> nla_free */
  SecBuffer ClientNonce; /* Depending on protocol version a random nonce or a value read from the
                            server. */

  SecBuffer negoToken;
  SecBuffer pubKeyAuth;
  SecBuffer authInfo;
  SecBuffer PublicKey;
  SecBuffer tsCredentials;

  SEC_WINNT_AUTH_IDENTITY* identity;

  rdpCredsspAuth* auth;
  char* pkinitArgs;
  SmartcardCertInfo* smartcardCert;
  BYTE certSha1[20];
  BOOL earlyUserAuth;
};

static BOOL nla_send(rdpNla* nla);
static int nla_server_recv(rdpNla* nla);
static BOOL nla_encrypt_public_key_echo(rdpNla* nla);
static BOOL nla_encrypt_public_key_hash(rdpNla* nla);
static BOOL nla_decrypt_public_key_echo(rdpNla* nla);
static BOOL nla_decrypt_public_key_hash(rdpNla* nla);
static BOOL nla_encrypt_ts_credentials(rdpNla* nla);
static BOOL nla_decrypt_ts_credentials(rdpNla* nla);

void nla_set_early_user_auth(rdpNla* nla, BOOL earlyUserAuth)
{
  WINPR_ASSERT(nla);
  WLog_DBG(TAG, "Early User Auth active: %s", earlyUserAuth ? "true" : "false");
  nla->earlyUserAuth = earlyUserAuth;
}

static void nla_buffer_free(rdpNla* nla)
{
  WINPR_ASSERT(nla);
  sspi_SecBufferFree(&nla->pubKeyAuth);
  sspi_SecBufferFree(&nla->authInfo);
  sspi_SecBufferFree(&nla->negoToken);
  sspi_SecBufferFree(&nla->ClientNonce);
  sspi_SecBufferFree(&nla->PublicKey);
}

static BOOL nla_Digest_Update_From_SecBuffer(WINPR_DIGEST_CTX* ctx, const SecBuffer* buffer)
{
  if (!buffer)
    return FALSE;
  return winpr_Digest_Update(ctx, buffer->pvBuffer, buffer->cbBuffer);
}

static BOOL nla_sec_buffer_alloc(SecBuffer* buffer, size_t size)
{
  WINPR_ASSERT(buffer);
  sspi_SecBufferFree(buffer);
  if (size > ULONG_MAX)
    return FALSE;
  if (!sspi_SecBufferAlloc(buffer, (ULONG)size))
    return FALSE;

  WINPR_ASSERT(buffer);
  buffer->BufferType = SECBUFFER_TOKEN;
  return TRUE;
}

static BOOL nla_sec_buffer_alloc_from_data(SecBuffer* buffer, const BYTE* data, size_t offset,
                                           size_t size)
{
  if (!nla_sec_buffer_alloc(buffer, offset + size))
    return FALSE;

  WINPR_ASSERT(buffer);
  BYTE* pb = buffer->pvBuffer;
  memcpy(&pb[offset], data, size);
  return TRUE;
}

/* CredSSP Client-To-Server Binding Hash\0 */
static const BYTE ClientServerHashMagic[] = { 0x43, 0x72, 0x65, 0x64, 0x53, 0x53, 0x50, 0x20,
                                            0x43, 0x6C, 0x69, 0x65, 0x6E, 0x74, 0x2D, 0x54,
                                            0x6F, 0x2D, 0x53, 0x65, 0x72, 0x76, 0x65, 0x72,
                                            0x20, 0x42, 0x69, 0x6E, 0x64, 0x69, 0x6E, 0x67,
                                            0x20, 0x48, 0x61, 0x73, 0x68, 0x00 };

/* CredSSP Server-To-Client Binding Hash\0 */
static const BYTE ServerClientHashMagic[] = { 0x43, 0x72, 0x65, 0x64, 0x53, 0x53, 0x50, 0x20,
                                            0x53, 0x65, 0x72, 0x76, 0x65, 0x72, 0x2D, 0x54,
                                            0x6F, 0x2D, 0x43, 0x6C, 0x69, 0x65, 0x6E, 0x74,
                                            0x20, 0x42, 0x69, 0x6E, 0x64, 0x69, 0x6E, 0x67,
                                            0x20, 0x48, 0x61, 0x73, 0x68, 0x00 };

static const UINT32 NonceLength = 32;

static BOOL nla_adjust_settings_from_smartcard(rdpNla* nla)
{
  BOOL ret = FALSE;

  WINPR_ASSERT(nla);
  WINPR_ASSERT(nla->rdpcontext);

  rdpSettings* settings = nla->rdpcontext->settings;
  WINPR_ASSERT(settings);

  if (!settings->SmartcardLogon)
    return TRUE;

  smartcardCertInfo_Free(nla->smartcardCert);

  if (!smartcard_getCert(nla->rdpcontext, &nla->smartcardCert, FALSE))
  {
    WLog_ERR(TAG, "unable to get smartcard certificate for logon");
    return FALSE;
  }

  if (!settings->CspName)
  {
    if (nla->smartcardCert->csp && !freerdp_settings_set_string_from_utf16(
                                       settings, FreeRDP_CspName, nla->smartcardCert->csp))
    {
      WLog_ERR(TAG, "unable to set CSP name");
      goto out;
    }
    if (!settings->CspName &&
        !freerdp_settings_set_string(settings, FreeRDP_CspName, MS_SCARD_PROV_A))
    {
      WLog_ERR(TAG, "unable to set CSP name");
      goto out;
    }
  }

  if (!settings->ReaderName && nla->smartcardCert->reader)
  {
    if (!freerdp_settings_set_string_from_utf16(settings, FreeRDP_ReaderName,
                                                nla->smartcardCert->reader))
    {
      WLog_ERR(TAG, "unable to copy reader name");
      goto out;
    }
  }

  if (!settings->ContainerName && nla->smartcardCert->containerName)
  {
    if (!freerdp_settings_set_string_from_utf16(settings, FreeRDP_ContainerName,
                                                nla->smartcardCert->containerName))
    {
      WLog_ERR(TAG, "unable to copy container name");
      goto out;
    }
  }

  memcpy(nla->certSha1, nla->smartcardCert->sha1Hash, sizeof(nla->certSha1));

  if (nla->smartcardCert->pkinitArgs)
  {
    nla->pkinitArgs = _strdup(nla->smartcardCert->pkinitArgs);
    if (!nla->pkinitArgs)
    {
      WLog_ERR(TAG, "unable to copy pkinitArgs");
      goto out;
    }
  }

  ret = TRUE;
out:
  return ret;
}

static BOOL nla_client_setup_identity(rdpNla* nla)
{
  BOOL PromptPassword = FALSE;

  WINPR_ASSERT(nla);
  WINPR_ASSERT(nla->rdpcontext);

  rdpSettings* settings = nla->rdpcontext->settings;
  WINPR_ASSERT(settings);

  freerdp* instance = nla->rdpcontext->instance;
  WINPR_ASSERT(instance);

  /* */
  if ((utils_str_is_empty(settings->Username) ||
       (utils_str_is_empty(settings->Password) &&
        utils_str_is_empty((const char*)settings->RedirectionPassword))))
  {
    PromptPassword = TRUE;
  }

  if (PromptPassword && !utils_str_is_empty(settings->Username))
  {
    WINPR_SAM* sam = SamOpen(NULL, TRUE);
    if (sam)
    {
      const size_t userLength = strlen(settings->Username);
      WINPR_SAM_ENTRY* entry = SamLookupUserA(
          sam, settings->Username, userLength + 1 /* ensure '\0' is checked too */, NULL, 0);
      if (entry)
      {
        /**
         * The user could be found in SAM database.
         * Use entry in SAM database later instead of prompt
         */
        PromptPassword = FALSE;
        SamFreeEntry(sam, entry);
      }

      SamClose(sam);
    }
  }

  if (PromptPassword)
  {
    if (settings->RestrictedAdminModeRequired)
    {
      if ((settings->PasswordHash) && (strlen(settings->PasswordHash) > 0))
        PromptPassword = FALSE;
    }

    if (settings->RemoteCredentialGuard)
      PromptPassword = FALSE;
  }

  BOOL smartCardLogonWasDisabled = !settings->SmartcardLogon;
  if (PromptPassword)
  {
    switch (utils_authenticate(instance, AUTH_NLA, TRUE))
    {
      case AUTH_SKIP:
      case AUTH_SUCCESS:
        break;
      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");
        break;
      default:
        return FALSE;
    }
  }

  if (!settings->Username)
  {
    sspi_FreeAuthIdentity(nla->identity);
    nla->identity = NULL;
  }
  else if (settings->SmartcardLogon)
  {
    if (smartCardLogonWasDisabled)
    {
      if (!nla_adjust_settings_from_smartcard(nla))
        return FALSE;
    }

    if (!identity_set_from_smartcard_hash(nla->identity, settings, FreeRDP_Username,
                                          FreeRDP_Domain, FreeRDP_Password, nla->certSha1,
                                          sizeof(nla->certSha1)))
      return FALSE;
  }
  else
  {
    BOOL usePassword = TRUE;

    if (settings->RedirectionPassword && (settings->RedirectionPasswordLength > 0))
    {
      if (!identity_set_from_settings_with_pwd(
              nla->identity, settings, FreeRDP_Username, FreeRDP_Domain,
              (const WCHAR*)settings->RedirectionPassword,
              settings->RedirectionPasswordLength / sizeof(WCHAR)))
        return FALSE;

      usePassword = FALSE;
    }

    if (settings->RestrictedAdminModeRequired)
    {
      if (settings->PasswordHash && strlen(settings->PasswordHash) == 32)
      {
        if (!identity_set_from_settings(nla->identity, settings, FreeRDP_Username,
                                        FreeRDP_Domain, FreeRDP_PasswordHash))
          return FALSE;

        /**
         * Increase password hash length by LB_PASSWORD_MAX_LENGTH to obtain a
         * length exceeding the maximum (LB_PASSWORD_MAX_LENGTH) and use it this for
         * hash identification in WinPR.
         */
        nla->identity->PasswordLength += LB_PASSWORD_MAX_LENGTH;
        usePassword = FALSE;
      }
    }

    if (usePassword)
    {
      if (!identity_set_from_settings(nla->identity, settings, FreeRDP_Username,
                                      FreeRDP_Domain, FreeRDP_Password))
        return FALSE;
    }
  }

  return TRUE;
}

static int nla_client_init(rdpNla* nla)
{
  WINPR_ASSERT(nla);
  WINPR_ASSERT(nla->rdpcontext);

  rdpSettings* settings = nla->rdpcontext->settings;
  WINPR_ASSERT(settings);

  nla_set_state(nla, NLA_STATE_INITIAL);

  if (!nla_adjust_settings_from_smartcard(nla))
    return -1;

  if (!credssp_auth_init(nla->auth, NLA_AUTH_PKG, NULL))
    return -1;

  if (!nla_client_setup_identity(nla))
    return -1;

  const char* hostname = freerdp_settings_get_server_name(settings);

  if (!credssp_auth_setup_client(nla->auth, "TERMSRV", hostname, nla->identity, nla->pkinitArgs))
    return -1;

  const BYTE* data = NULL;
  DWORD length = 0;
  if (!transport_get_public_key(nla->transport, &data, &length))
  {
    WLog_ERR(TAG, "Failed to get public key");
    return -1;
  }

  if (!nla_sec_buffer_alloc_from_data(&nla->PublicKey, data, 0, length))
  {
    WLog_ERR(TAG, "Failed to allocate sspi secBuffer");
    return -1;
  }

  return 1;
}

int nla_client_begin(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  if (nla_client_init(nla) < 1)
    return -1;

  if (nla_get_state(nla) != NLA_STATE_INITIAL)
    return -1;

  /*
   * from tspkg.dll: 0x00000132
   * ISC_REQ_MUTUAL_AUTH
   * ISC_REQ_CONFIDENTIALITY
   * ISC_REQ_USE_SESSION_KEY
   * ISC_REQ_ALLOCATE_MEMORY
   */
  credssp_auth_set_flags(nla->auth, ISC_REQ_MUTUAL_AUTH | ISC_REQ_CONFIDENTIALITY);

  const int rc = credssp_auth_authenticate(nla->auth);

  switch (rc)
  {
    case 0:
      if (!nla_send(nla))
        return -1;
      nla_set_state(nla, NLA_STATE_NEGO_TOKEN);
      break;
    case 1:
      if (credssp_auth_have_output_token(nla->auth))
      {
        if (!nla_send(nla))
          return -1;
      }
      nla_set_state(nla, NLA_STATE_FINAL);
      break;
    default:
      switch (credssp_auth_sspi_error(nla->auth))
      {
        case SEC_E_LOGON_DENIED:
        case SEC_E_NO_CREDENTIALS:
          freerdp_set_last_error_log(nla->rdpcontext,
                                     FREERDP_ERROR_CONNECT_LOGON_FAILURE);
          break;
        default:
          break;
      }
      return -1;
  }

  return 1;
}

static int nla_client_recv_nego_token(rdpNla* nla)
{
  credssp_auth_take_input_buffer(nla->auth, &nla->negoToken);
  const int rc = credssp_auth_authenticate(nla->auth);

  switch (rc)
  {
    case 0:
      if (!nla_send(nla))
        return -1;
      break;
    case 1: /* completed */
    {
      int res = -1;
      if (nla->peerVersion < 5)
        res = nla_encrypt_public_key_echo(nla);
      else
        res = nla_encrypt_public_key_hash(nla);

      if (!res)
        return -1;

      if (!nla_send(nla))
        return -1;

      nla_set_state(nla, NLA_STATE_PUB_KEY_AUTH);
    }
    break;

    default:
      return -1;
  }

  return 1;
}

static int nla_client_recv_pub_key_auth(rdpNla* nla)
{
  BOOL rc = FALSE;

  WINPR_ASSERT(nla);

  /* Verify Server Public Key Echo */
  if (nla->peerVersion < 5)
    rc = nla_decrypt_public_key_echo(nla);
  else
    rc = nla_decrypt_public_key_hash(nla);

  sspi_SecBufferFree(&nla->pubKeyAuth);

  if (!rc)
    return -1;

  /* Send encrypted credentials */
  rc = nla_encrypt_ts_credentials(nla);
  if (!rc)
    return -1;

  if (!nla_send(nla))
    return -1;

  if (nla->earlyUserAuth)
  {
    transport_set_early_user_auth_mode(nla->transport, TRUE);
    nla_set_state(nla, NLA_STATE_EARLY_USER_AUTH);
  }
  else
    nla_set_state(nla, NLA_STATE_AUTH_INFO);
  return 1;
}

static int nla_client_recv_early_user_auth(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  transport_set_early_user_auth_mode(nla->transport, FALSE);
  nla_set_state(nla, NLA_STATE_AUTH_INFO);
  return 1;
}

static int nla_client_recv(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  switch (nla_get_state(nla))
  {
    case NLA_STATE_NEGO_TOKEN:
      return nla_client_recv_nego_token(nla);

    case NLA_STATE_PUB_KEY_AUTH:
      return nla_client_recv_pub_key_auth(nla);

    case NLA_STATE_EARLY_USER_AUTH:
      return nla_client_recv_early_user_auth(nla);

    case NLA_STATE_FINAL:
    default:
      WLog_ERR(TAG, "NLA in invalid client receive state %s",
               nla_get_state_str(nla_get_state(nla)));
      return -1;
  }
}

static int nla_client_authenticate(rdpNla* nla)
{
  int rc = -1;

  WINPR_ASSERT(nla);

  wStream* s = Stream_New(NULL, 4096);

  if (!s)
  {
    WLog_ERR(TAG, "Stream_New failed!");
    return -1;
  }

  if (nla_client_begin(nla) < 1)
    goto fail;

  while (nla_get_state(nla) < NLA_STATE_AUTH_INFO)
  {
    Stream_SetPosition(s, 0);
    const int status = transport_read_pdu(nla->transport, s);

    if (status < 0)
    {
      WLog_ERR(TAG, "nla_client_authenticate failure");
      goto fail;
    }

    const int status2 = nla_recv_pdu(nla, s);

    if (status2 < 0)
      goto fail;
  }

  rc = 1;
fail:
  Stream_Free(s, TRUE);
  return rc;
}

/**
 * Initialize NTLMSSP authentication module (server).
 */

static int nla_server_init(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  const BYTE* data = NULL;
  DWORD length = 0;
  if (!transport_get_public_key(nla->transport, &data, &length))
  {
    WLog_ERR(TAG, "Failed to get public key");
    return -1;
  }

  if (!nla_sec_buffer_alloc_from_data(&nla->PublicKey, data, 0, length))
  {
    WLog_ERR(TAG, "Failed to allocate SecBuffer for public key");
    return -1;
  }

  if (!credssp_auth_init(nla->auth, NLA_AUTH_PKG, NULL))
    return -1;

  if (!credssp_auth_setup_server(nla->auth))
    return -1;

  nla_set_state(nla, NLA_STATE_INITIAL);
  return 1;
}

static wStream* nla_server_recv_stream(rdpNla* nla)
{
  wStream* s = NULL;
  int status = -1;

  WINPR_ASSERT(nla);

  s = Stream_New(NULL, 4096);

  if (!s)
    goto fail;

  status = transport_read_pdu(nla->transport, s);

fail:
  if (status < 0)
  {
    WLog_ERR(TAG, "nla_recv() error: %d", status);
    Stream_Free(s, TRUE);
    return NULL;
  }

  return s;
}

static BOOL nla_server_recv_credentials(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  if (nla_server_recv(nla) < 0)
    return FALSE;

  if (!nla_decrypt_ts_credentials(nla))
    return FALSE;

  if (!nla_impersonate(nla))
    return FALSE;

  if (!nla_revert_to_self(nla))
    return FALSE;

  return TRUE;
}

/**
 * Authenticate with client using CredSSP (server).
 * @param nla The NLA instance to use
 *
 * @return 1 if authentication is successful
 */

static int nla_server_authenticate(rdpNla* nla)
{
  int ret = -1;

  WINPR_ASSERT(nla);

  if (nla_server_init(nla) < 1)
    goto fail;

  /*
   * from tspkg.dll: 0x00000112
   * ASC_REQ_MUTUAL_AUTH
   * ASC_REQ_CONFIDENTIALITY
   * ASC_REQ_ALLOCATE_MEMORY
   */
  credssp_auth_set_flags(nla->auth, ASC_REQ_MUTUAL_AUTH | ASC_REQ_CONFIDENTIALITY |
                                        ASC_REQ_CONNECTION | ASC_REQ_USE_SESSION_KEY |
                                        ASC_REQ_SEQUENCE_DETECT | ASC_REQ_EXTENDED_ERROR);

  /* Client is starting, here es the state machine:
   *
   *  -- NLA_STATE_INITIAL  --> NLA_STATE_INITIAL
   * ----->> sending...
   *    ----->> protocol version 6
   *    ----->> nego token
   *    ----->> client nonce
   * <<----- receiving...
   *    <<----- protocol version 6
   *    <<----- nego token
   * ----->> sending...
   *    ----->> protocol version 6
   *    ----->> nego token
   *    ----->> public key auth
   *    ----->> client nonce
   * -- NLA_STATE_NEGO_TOKEN  --> NLA_STATE_PUB_KEY_AUTH
   * <<----- receiving...
   *    <<----- protocol version 6
   *    <<----- public key info
   * ----->> sending...
   *    ----->> protocol version 6
   *    ----->> auth info
   *    ----->> client nonce
   * -- NLA_STATE_PUB_KEY_AUTH  --> NLA_STATE
   */

  while (TRUE)
  {
    int res = -1;

    if (nla_server_recv(nla) < 0)
      goto fail;

    WLog_DBG(TAG, "Receiving Authentication Token");
    credssp_auth_take_input_buffer(nla->auth, &nla->negoToken);

    res = credssp_auth_authenticate(nla->auth);

    if (res == -1)
    {
      /* Special handling of these specific error codes as NTSTATUS_FROM_WIN32
         unfortunately does not map directly to the corresponding NTSTATUS values
       */
      switch (GetLastError())
      {
        case ERROR_PASSWORD_MUST_CHANGE:
          nla->errorCode = STATUS_PASSWORD_MUST_CHANGE;
          break;

        case ERROR_PASSWORD_EXPIRED:
          nla->errorCode = STATUS_PASSWORD_EXPIRED;
          break;

        case ERROR_ACCOUNT_DISABLED:
          nla->errorCode = STATUS_ACCOUNT_DISABLED;
          break;

        default:
          nla->errorCode = NTSTATUS_FROM_WIN32(GetLastError());
          break;
      }

      (void)nla_send(nla);
      /* Access Denied */
      goto fail;
    }

    if (res == 1)
    {
      /* Process final part of the nego token exchange */
      if (credssp_auth_have_output_token(nla->auth))
      {
        if (!nla_send(nla))
          goto fail;

        if (nla_server_recv(nla) < 0)
          goto fail;

        WLog_DBG(TAG, "Receiving pubkey Token");
      }

      if (nla->peerVersion < 5)
        res = nla_decrypt_public_key_echo(nla);
      else
        res = nla_decrypt_public_key_hash(nla);

      if (!res)
        goto fail;

      /* Clear nego token buffer or we will send it again to the client */
      sspi_SecBufferFree(&nla->negoToken);

      if (nla->peerVersion < 5)
        res = nla_encrypt_public_key_echo(nla);
      else
        res = nla_encrypt_public_key_hash(nla);

      if (!res)
        goto fail;
    }

    /* send authentication token */
    WLog_DBG(TAG, "Sending Authentication Token");

    if (!nla_send(nla))
      goto fail;

    if (res == 1)
    {
      ret = 1;
      break;
    }
  }

  /* Receive encrypted credentials */
  if (!nla_server_recv_credentials(nla))
    ret = -1;

fail:
  nla_buffer_free(nla);
  return ret;
}

/**
 * Authenticate using CredSSP.
 * @param nla The NLA instance to use
 *
 * @return 1 if authentication is successful
 */

int nla_authenticate(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  if (nla->server)
    return nla_server_authenticate(nla);
  else
    return nla_client_authenticate(nla);
}

static void ap_integer_increment_le(BYTE* number, size_t size)
{
  WINPR_ASSERT(number || (size == 0));

  for (size_t index = 0; index < size; index++)
  {
    if (number[index] < 0xFF)
    {
      number[index]++;
      break;
    }
    else
    {
      number[index] = 0;
      continue;
    }
  }
}

static void ap_integer_decrement_le(BYTE* number, size_t size)
{
  WINPR_ASSERT(number || (size == 0));

  for (size_t index = 0; index < size; index++)
  {
    if (number[index] > 0)
    {
      number[index]--;
      break;
    }
    else
    {
      number[index] = 0xFF;
      continue;
    }
  }
}

BOOL nla_encrypt_public_key_echo(rdpNla* nla)
{
  BOOL status = FALSE;

  WINPR_ASSERT(nla);

  sspi_SecBufferFree(&nla->pubKeyAuth);
  if (nla->server)
  {
    SecBuffer buf = { 0 };
    if (!sspi_SecBufferAlloc(&buf, nla->PublicKey.cbBuffer))
      return FALSE;
    ap_integer_increment_le(buf.pvBuffer, buf.cbBuffer);
    status = credssp_auth_encrypt(nla->auth, &buf, &nla->pubKeyAuth, NULL, nla->sendSeqNum++);
    sspi_SecBufferFree(&buf);
  }
  else
  {
    status = credssp_auth_encrypt(nla->auth, &nla->PublicKey, &nla->pubKeyAuth, NULL,
                                  nla->sendSeqNum++);
  }

  return status;
}

BOOL nla_encrypt_public_key_hash(rdpNla* nla)
{
  BOOL status = FALSE;
  WINPR_DIGEST_CTX* sha256 = NULL;
  SecBuffer buf = { 0 };

  WINPR_ASSERT(nla);

  const BYTE* hashMagic = nla->server ? ServerClientHashMagic : ClientServerHashMagic;
  const size_t hashSize =
      nla->server ? sizeof(ServerClientHashMagic) : sizeof(ClientServerHashMagic);

  if (!sspi_SecBufferAlloc(&buf, WINPR_SHA256_DIGEST_LENGTH))
    return FALSE;

  /* generate SHA256 of following data: ClientServerHashMagic, Nonce, SubjectPublicKey */
  if (!(sha256 = winpr_Digest_New()))
    goto out;

  if (!winpr_Digest_Init(sha256, WINPR_MD_SHA256))
    goto out;

  /* include trailing \0 from hashMagic */
  if (!winpr_Digest_Update(sha256, hashMagic, hashSize))
    goto out;

  if (!nla_Digest_Update_From_SecBuffer(sha256, &nla->ClientNonce))
    goto out;

  /* SubjectPublicKey */
  if (!nla_Digest_Update_From_SecBuffer(sha256, &nla->PublicKey))
    goto out;

  if (!winpr_Digest_Final(sha256, buf.pvBuffer, WINPR_SHA256_DIGEST_LENGTH))
    goto out;

  sspi_SecBufferFree(&nla->pubKeyAuth);
  if (!credssp_auth_encrypt(nla->auth, &buf, &nla->pubKeyAuth, NULL, nla->sendSeqNum++))
    goto out;

  status = TRUE;

out:
  winpr_Digest_Free(sha256);
  sspi_SecBufferFree(&buf);
  return status;
}

BOOL nla_decrypt_public_key_echo(rdpNla* nla)
{
  BOOL status = FALSE;
  SecBuffer public_key = { 0 };

  if (!nla)
    goto fail;

  if (!credssp_auth_decrypt(nla->auth, &nla->pubKeyAuth, &public_key, nla->recvSeqNum++))
    return FALSE;

  if (!nla->server)
  {
    /* server echos the public key +1 */
    ap_integer_decrement_le(public_key.pvBuffer, public_key.cbBuffer);
  }

  if (public_key.cbBuffer != nla->PublicKey.cbBuffer ||
      memcmp(public_key.pvBuffer, nla->PublicKey.pvBuffer, public_key.cbBuffer) != 0)
  {
    WLog_ERR(TAG, "Could not verify server's public key echo");
#if defined(WITH_DEBUG_NLA)
    WLog_ERR(TAG, "Expected (length = %" PRIu32 "):", nla->PublicKey.cbBuffer);
    winpr_HexDump(TAG, WLOG_ERROR, nla->PublicKey.pvBuffer, nla->PublicKey.cbBuffer);
    WLog_ERR(TAG, "Actual (length = %" PRIu32 "):", public_key.cbBuffer);
    winpr_HexDump(TAG, WLOG_ERROR, public_key.pvBuffer, public_key.cbBuffer);
#endif
    /* DO NOT SEND CREDENTIALS! */
    goto fail;
  }

  status = TRUE;
fail:
  sspi_SecBufferFree(&public_key);
  return status;
}

BOOL nla_decrypt_public_key_hash(rdpNla* nla)
{
  WINPR_DIGEST_CTX* sha256 = NULL;
  BYTE serverClientHash[WINPR_SHA256_DIGEST_LENGTH] = { 0 };
  BOOL status = FALSE;

  WINPR_ASSERT(nla);

  const BYTE* hashMagic = nla->server ? ClientServerHashMagic : ServerClientHashMagic;
  const size_t hashSize =
      nla->server ? sizeof(ClientServerHashMagic) : sizeof(ServerClientHashMagic);
  SecBuffer hash = { 0 };

  if (!credssp_auth_decrypt(nla->auth, &nla->pubKeyAuth, &hash, nla->recvSeqNum++))
    return FALSE;

  /* generate SHA256 of following data: ServerClientHashMagic, Nonce, SubjectPublicKey */
  if (!(sha256 = winpr_Digest_New()))
    goto fail;

  if (!winpr_Digest_Init(sha256, WINPR_MD_SHA256))
    goto fail;

  /* include trailing \0 from hashMagic */
  if (!winpr_Digest_Update(sha256, hashMagic, hashSize))
    goto fail;

  if (!nla_Digest_Update_From_SecBuffer(sha256, &nla->ClientNonce))
    goto fail;

  /* SubjectPublicKey */
  if (!nla_Digest_Update_From_SecBuffer(sha256, &nla->PublicKey))
    goto fail;

  if (!winpr_Digest_Final(sha256, serverClientHash, sizeof(serverClientHash)))
    goto fail;

  /* verify hash */
  if (hash.cbBuffer != WINPR_SHA256_DIGEST_LENGTH ||
      memcmp(serverClientHash, hash.pvBuffer, WINPR_SHA256_DIGEST_LENGTH) != 0)
  {
    WLog_ERR(TAG, "Could not verify server's hash");
    /* DO NOT SEND CREDENTIALS! */
    goto fail;
  }

  status = TRUE;
fail:
  winpr_Digest_Free(sha256);
  sspi_SecBufferFree(&hash);
  return status;
}

static BOOL set_creds_octetstring_to_settings(WinPrAsn1Decoder* dec, WinPrAsn1_tagId tagId,
                                              BOOL optional, FreeRDP_Settings_Keys_String settingId,
                                              rdpSettings* settings)
{
  if (optional)
  {
    WinPrAsn1_tagId itemTag = 0;
    if (!WinPrAsn1DecPeekTag(dec, &itemTag) || (itemTag != tagId))
      return TRUE;
  }

  BOOL error = FALSE;
  WinPrAsn1_OctetString value;
  /* note: not checking "error" value, as the not present optional item case is handled above
   *       if the function fails it's because of a real error not because the item is not present
   */
  if (!WinPrAsn1DecReadContextualOctetString(dec, tagId, &error, &value, FALSE))
    return FALSE;

  return freerdp_settings_set_string_from_utf16N(settings, settingId, (const WCHAR*)value.data,
                                                 value.len / sizeof(WCHAR));
}

static BOOL nla_read_TSCspDataDetail(WinPrAsn1Decoder* dec, rdpSettings* settings)
{
  BOOL error = FALSE;

  /* keySpec [0] INTEGER */
  WinPrAsn1_INTEGER keyspec = 0;
  if (!WinPrAsn1DecReadContextualInteger(dec, 0, &error, &keyspec))
    return FALSE;
  settings->KeySpec = (UINT32)keyspec;

  /* cardName [1] OCTET STRING OPTIONAL */
  if (!set_creds_octetstring_to_settings(dec, 1, TRUE, FreeRDP_CardName, settings))
    return FALSE;

  /* readerName [2] OCTET STRING OPTIONAL */
  if (!set_creds_octetstring_to_settings(dec, 2, TRUE, FreeRDP_ReaderName, settings))
    return FALSE;

  /* containerName [3] OCTET STRING OPTIONAL */
  if (!set_creds_octetstring_to_settings(dec, 3, TRUE, FreeRDP_ContainerName, settings))
    return FALSE;

  /* cspName [4] OCTET STRING OPTIONAL */
  return set_creds_octetstring_to_settings(dec, 4, TRUE, FreeRDP_CspName, settings);
}

static BOOL nla_read_KERB_TICKET_LOGON(rdpNla* nla, wStream* s, KERB_TICKET_LOGON* ticket)
{
  WINPR_ASSERT(nla);

  if (!ticket)
    return FALSE;

  /* mysterious extra 16 bytes before TGS/TGT content */
  if (!Stream_CheckAndLogRequiredLength(TAG, s, 16 + 16))
    return FALSE;

  Stream_Read_UINT32(s, ticket->MessageType);
  Stream_Read_UINT32(s, ticket->Flags);
  Stream_Read_UINT32(s, ticket->ServiceTicketLength);
  Stream_Read_UINT32(s, ticket->TicketGrantingTicketLength);

  if (ticket->MessageType != KerbTicketLogon)
  {
    WLog_ERR(TAG, "Not a KerbTicketLogon");
    return FALSE;
  }

  if (!Stream_CheckAndLogRequiredLength(
          TAG, s, 16ull + ticket->ServiceTicketLength + ticket->TicketGrantingTicketLength))
    return FALSE;

  /* mysterious 16 bytes in the way, maybe they would need to be interpreted... */
  Stream_Seek(s, 16);

  /*WLog_INFO(TAG, "TGS");
  winpr_HexDump(TAG, WLOG_DEBUG, Stream_PointerAs(s, const BYTE), ticket->ServiceTicketLength);*/
  ticket->ServiceTicket = Stream_PointerAs(s, UCHAR);
  Stream_Seek(s, ticket->ServiceTicketLength);

  /*WLog_INFO(TAG, "TGT");
  winpr_HexDump(TAG, WLOG_DEBUG, Stream_PointerAs(s, const BYTE),
                ticket->TicketGrantingTicketLength);*/
  ticket->TicketGrantingTicket = Stream_PointerAs(s, UCHAR);
  return TRUE;
}

/** @brief kind of RCG credentials */
typedef enum
{
  RCG_TYPE_KERB,
  RCG_TYPE_NTLM
} RemoteGuardPackageCredType;

static BOOL nla_read_TSRemoteGuardPackageCred(rdpNla* nla, WinPrAsn1Decoder* dec,
                                              RemoteGuardPackageCredType* credsType,
                                              wStream* payload)
{
  WinPrAsn1_OctetString packageName = { 0 };
  WinPrAsn1_OctetString credBuffer = { 0 };
  BOOL error = FALSE;
  char packageNameStr[100] = { 0 };

  /* packageName [0] OCTET STRING */
  if (!WinPrAsn1DecReadContextualOctetString(dec, 0, &error, &packageName, FALSE) || error)
    return TRUE;

  ConvertMszWCharNToUtf8((WCHAR*)packageName.data, packageName.len / sizeof(WCHAR),
                         packageNameStr, 100);
  WLog_DBG(TAG, "TSRemoteGuardPackageCred(%s)", packageNameStr);

  /* credBuffer [1] OCTET STRING, */
  if (!WinPrAsn1DecReadContextualOctetString(dec, 1, &error, &credBuffer, FALSE) || error)
    return TRUE;

  if (_stricmp(packageNameStr, "Kerberos") == 0)
  {
    *credsType = RCG_TYPE_KERB;
  }
  else if (_stricmp(packageNameStr, "NTLM") == 0)
  {
    *credsType = RCG_TYPE_NTLM;
  }
  else
  {
    WLog_INFO(TAG, "TSRemoteGuardPackageCred package %s not handled", packageNameStr);
    return FALSE;
  }

  Stream_StaticInit(payload, credBuffer.data, credBuffer.len);
  return TRUE;
}

/** @brief kind of TSCreds */
typedef enum
{
  TSCREDS_INVALID = 0,
  TSCREDS_USER_PASSWD = 1,
  TSCREDS_SMARTCARD = 2,
  TSCREDS_REMOTEGUARD = 6
} TsCredentialsType;

static BOOL nla_read_ts_credentials(rdpNla* nla, SecBuffer* data)
{
  WinPrAsn1Decoder dec = { 0 };
  WinPrAsn1Decoder dec2 = { 0 };
  WinPrAsn1_OctetString credentials = { 0 };
  BOOL error = FALSE;
  WinPrAsn1_INTEGER credType = -1;
  BOOL ret = TRUE;

  WINPR_ASSERT(nla);
  WINPR_ASSERT(data);

  WinPrAsn1Decoder_InitMem(&dec, WINPR_ASN1_DER, (BYTE*)data->pvBuffer, data->cbBuffer);

  /* TSCredentials */
  if (!WinPrAsn1DecReadSequence(&dec, &dec2))
    return FALSE;
  dec = dec2;

  /* credType [0] INTEGER */
  if (!WinPrAsn1DecReadContextualInteger(&dec, 0, &error, &credType))
    return FALSE;

  /* credentials [1] OCTET STRING */
  if (!WinPrAsn1DecReadContextualOctetString(&dec, 1, &error, &credentials, FALSE))
    return FALSE;

  WinPrAsn1Decoder_InitMem(&dec, WINPR_ASN1_DER, credentials.data, credentials.len);

  rdpSettings* settings = nla->rdpcontext->settings;
  if (nego_get_remoteCredentialGuard(nla->rdpcontext->rdp->nego) &&
      credType != TSCREDS_REMOTEGUARD)
  {
    WLog_ERR(TAG, "connecting with RCG but it's not TSRemoteGuard credentials");
    return FALSE;
  }

  switch (credType)
  {
    case TSCREDS_USER_PASSWD:
    {
      /* TSPasswordCreds */
      if (!WinPrAsn1DecReadSequence(&dec, &dec2))
        return FALSE;
      dec = dec2;

      /* domainName [0] OCTET STRING */
      if (!set_creds_octetstring_to_settings(&dec, 0, FALSE, FreeRDP_Domain, settings))
        return FALSE;

      /* userName [1] OCTET STRING */
      if (!set_creds_octetstring_to_settings(&dec, 1, FALSE, FreeRDP_Username, settings))
        return FALSE;

      /* password [2] OCTET STRING */
      return set_creds_octetstring_to_settings(&dec, 2, FALSE, FreeRDP_Password, settings);
    }
    case TSCREDS_SMARTCARD:
    {
      /* TSSmartCardCreds */
      if (!WinPrAsn1DecReadSequence(&dec, &dec2))
        return FALSE;
      dec = dec2;

      /* pin [0] OCTET STRING, */
      if (!set_creds_octetstring_to_settings(&dec, 0, FALSE, FreeRDP_Password, settings))
        return FALSE;
      settings->PasswordIsSmartcardPin = TRUE;

      /* cspData [1] TSCspDataDetail */
      WinPrAsn1Decoder cspDetails = { 0 };
      if (!WinPrAsn1DecReadContextualSequence(&dec, 1, &error, &cspDetails) && error)
        return FALSE;
      if (!nla_read_TSCspDataDetail(&cspDetails, settings))
        return FALSE;

      /* userHint [2] OCTET STRING OPTIONAL */
      if (!set_creds_octetstring_to_settings(&dec, 2, TRUE, FreeRDP_Username, settings))
        return FALSE;

      /* domainHint [3] OCTET STRING OPTIONAL */
      return set_creds_octetstring_to_settings(&dec, 3, TRUE, FreeRDP_Domain, settings);
    }
    case TSCREDS_REMOTEGUARD:
    {
      /* TSRemoteGuardCreds */
      if (!WinPrAsn1DecReadSequence(&dec, &dec2))
        return FALSE;

      /* logonCred[0] TSRemoteGuardPackageCred */
      KERB_TICKET_LOGON kerbLogon = { 0 };
      WinPrAsn1Decoder logonCredsSeq = { 0 };
      if (!WinPrAsn1DecReadContextualSequence(&dec2, 0, &error, &logonCredsSeq) || error)
        return FALSE;

      RemoteGuardPackageCredType logonCredsType = { 0 };
      wStream logonPayload = { 0 };
      if (!nla_read_TSRemoteGuardPackageCred(nla, &logonCredsSeq, &logonCredsType,
                                             &logonPayload))
        return FALSE;
      if (logonCredsType != RCG_TYPE_KERB)
      {
        WLog_ERR(TAG, "logonCred must be some Kerberos creds");
        return FALSE;
      }

      if (!nla_read_KERB_TICKET_LOGON(nla, &logonPayload, &kerbLogon))
      {
        WLog_ERR(TAG, "invalid KERB_TICKET_LOGON");
        return FALSE;
      }

      /* supplementalCreds [1] SEQUENCE OF TSRemoteGuardPackageCred OPTIONAL, */
      MSV1_0_SUPPLEMENTAL_CREDENTIAL* suppCreds = NULL;
      WinPrAsn1Decoder suppCredsSeq = { 0 };

      if (WinPrAsn1DecReadContextualSequence(&dec2, 1, &error, &suppCredsSeq))
      {
        WinPrAsn1Decoder ntlmCredsSeq = { 0 };
        if (!WinPrAsn1DecReadSequence(&suppCredsSeq, &ntlmCredsSeq))
          return FALSE;

        RemoteGuardPackageCredType suppCredsType = { 0 };
        wStream ntlmPayload = { 0 };
        if (!nla_read_TSRemoteGuardPackageCred(nla, &ntlmCredsSeq, &suppCredsType,
                                               &ntlmPayload))
          return FALSE;

        if (suppCredsType != RCG_TYPE_NTLM)
        {
          WLog_ERR(TAG, "supplementalCreds must be some NTLM creds");
          return FALSE;
        }

        /* TODO: suppCreds = &ntlmCreds; and parse NTLM creds */
      }
      else if (error)
      {
        WLog_ERR(TAG, "invalid supplementalCreds");
        return FALSE;
      }

      freerdp_peer* peer = nla->rdpcontext->peer;
      ret = IFCALLRESULT(TRUE, peer->RemoteCredentials, peer, &kerbLogon, suppCreds);
      break;
    }
    default:
      WLog_DBG(TAG, "TSCredentials type " PRIu32 " not supported for now", credType);
      ret = FALSE;
      break;
  }

  return ret;
}

/**
 * Encode TSCredentials structure.
 * @param nla A pointer to the NLA to use
 *
 * @return \b TRUE for success, \b FALSE otherwise
 */

static BOOL nla_encode_ts_credentials(rdpNla* nla)
{
  BOOL ret = FALSE;
  WinPrAsn1Encoder* enc = NULL;
  size_t length = 0;
  wStream s = { 0 };
  TsCredentialsType credType = TSCREDS_INVALID;

  WINPR_ASSERT(nla);
  WINPR_ASSERT(nla->rdpcontext);

  rdpSettings* settings = nla->rdpcontext->settings;
  WINPR_ASSERT(settings);

  if (settings->RemoteCredentialGuard)
    credType = TSCREDS_REMOTEGUARD;
  else if (settings->SmartcardLogon)
    credType = TSCREDS_SMARTCARD;
  else
    credType = TSCREDS_USER_PASSWD;

  enc = WinPrAsn1Encoder_New(WINPR_ASN1_DER);
  if (!enc)
    return FALSE;

  /* TSCredentials */
  if (!WinPrAsn1EncSeqContainer(enc))
    goto out;

  /* credType [0] INTEGER */
  if (!WinPrAsn1EncContextualInteger(enc, 0, (WinPrAsn1_INTEGER)credType))
    goto out;

  /* credentials [1] OCTET STRING */
  if (!WinPrAsn1EncContextualOctetStringContainer(enc, 1))
    goto out;

  switch (credType)
  {
    case TSCREDS_SMARTCARD:
    {
      struct
      {
        WinPrAsn1_tagId tag;
        size_t setting_id;
      } cspData_fields[] = { { 1, FreeRDP_CardName },
                           { 2, FreeRDP_ReaderName },
                           { 3, FreeRDP_ContainerName },
                           { 4, FreeRDP_CspName } };
      WinPrAsn1_OctetString octet_string = { 0 };

      /* TSSmartCardCreds */
      if (!WinPrAsn1EncSeqContainer(enc))
        goto out;

      /* pin [0] OCTET STRING */
      size_t ss = 0;
      octet_string.data =
          (BYTE*)freerdp_settings_get_string_as_utf16(settings, FreeRDP_Password, &ss);
      octet_string.len = ss * sizeof(WCHAR);
      const BOOL res = WinPrAsn1EncContextualOctetString(enc, 0, &octet_string) > 0;
      free(octet_string.data);
      if (!res)
        goto out;

      /* cspData [1] SEQUENCE */
      if (!WinPrAsn1EncContextualSeqContainer(enc, 1))
        goto out;

      /* keySpec [0] INTEGER */
      if (!WinPrAsn1EncContextualInteger(
              enc, 0, freerdp_settings_get_uint32(settings, FreeRDP_KeySpec)))
        goto out;

      for (size_t i = 0; i < ARRAYSIZE(cspData_fields); i++)
      {
        size_t len = 0;

        octet_string.data = (BYTE*)freerdp_settings_get_string_as_utf16(
            settings, cspData_fields[i].setting_id, &len);
        octet_string.len = len * sizeof(WCHAR);
        if (octet_string.len)
        {
          const BOOL res2 = WinPrAsn1EncContextualOctetString(enc, cspData_fields[i].tag,
                                                              &octet_string) > 0;
          free(octet_string.data);
          if (!res2)
            goto out;
        }
      }

      /* End cspData */
      if (!WinPrAsn1EncEndContainer(enc))
        goto out;

      /* End TSSmartCardCreds */
      if (!WinPrAsn1EncEndContainer(enc))
        goto out;
      break;
    }
    case TSCREDS_USER_PASSWD:
    {
      WinPrAsn1_OctetString username = { 0 };
      WinPrAsn1_OctetString domain = { 0 };
      WinPrAsn1_OctetString password = { 0 };

      /* TSPasswordCreds */
      if (!WinPrAsn1EncSeqContainer(enc))
        goto out;

      if (!settings->DisableCredentialsDelegation && nla->identity)
      {
        username.len = nla->identity->UserLength * sizeof(WCHAR);
        username.data = (BYTE*)nla->identity->User;

        domain.len = nla->identity->DomainLength * sizeof(WCHAR);
        domain.data = (BYTE*)nla->identity->Domain;

        password.len = nla->identity->PasswordLength * sizeof(WCHAR);
        password.data = (BYTE*)nla->identity->Password;
      }

      if (WinPrAsn1EncContextualOctetString(enc, 0, &domain) == 0)
        goto out;
      if (WinPrAsn1EncContextualOctetString(enc, 1, &username) == 0)
        goto out;
      if (WinPrAsn1EncContextualOctetString(enc, 2, &password) == 0)
        goto out;

      /* End TSPasswordCreds */
      if (!WinPrAsn1EncEndContainer(enc))
        goto out;
      break;
    }
    case TSCREDS_REMOTEGUARD:
    default:
      goto out;
  }

  /* End credentials | End TSCredentials */
  if (!WinPrAsn1EncEndContainer(enc) || !WinPrAsn1EncEndContainer(enc))
    goto out;

  if (!WinPrAsn1EncStreamSize(enc, &length))
    goto out;

  if (!nla_sec_buffer_alloc(&nla->tsCredentials, length))
  {
    WLog_ERR(TAG, "sspi_SecBufferAlloc failed!");
    goto out;
  }

  Stream_StaticInit(&s, (BYTE*)nla->tsCredentials.pvBuffer, length);

  ret = WinPrAsn1EncToStream(enc, &s);

out:
  WinPrAsn1Encoder_Free(&enc);
  return ret;
}

static BOOL nla_encrypt_ts_credentials(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  if (!nla_encode_ts_credentials(nla))
    return FALSE;

  sspi_SecBufferFree(&nla->authInfo);
  if (!credssp_auth_encrypt(nla->auth, &nla->tsCredentials, &nla->authInfo, NULL,
                            nla->sendSeqNum++))
    return FALSE;

  return TRUE;
}

static BOOL nla_decrypt_ts_credentials(rdpNla* nla)
{
  WINPR_ASSERT(nla);

  if (nla->authInfo.cbBuffer < 1)
  {
    WLog_ERR(TAG, "nla_decrypt_ts_credentials missing authInfo buffer");
    return FALSE;
  }

  sspi_SecBufferFree(&nla->tsCredentials);
  if (!credssp_auth_decrypt(nla->auth, &nla->authInfo, &nla->tsCredentials, nla->recvSeqNum++))
    return FALSE;

  if (!nla_read_ts_credentials(nla, &nla->tsCredentials))
    return FALSE;

  return TRUE;
}

static BOOL nla_write_octet_string(WinPrAsn1Encoder* enc, const SecBuffer* buffer,
                                   WinPrAsn1_tagId tagId, const char* msg)
{
  BOOL res = FALSE;

  WINPR_ASSERT(enc);
  WINPR_ASSERT(buffer);
  WINPR_ASSERT(msg);

  if (buffer->cbBuffer > 0)
  {
    size_t rc = 0;
    WinPrAsn1_OctetString octet_string = { 0 };

    WLog_DBG(TAG, "   ----->> %s", msg);
    octet_string.data = buffer->pvBuffer;
    octet_string.len = buffer->cbBuffer;
    rc = WinPrAsn1EncContextualOctetString(enc, tagId, &octet_string);
    if (rc != 0)
      res = TRUE;
  }

  return res;
}

static BOOL nla_write_octet_string_free(WinPrAsn1Encoder* enc, SecBuffer* buffer,
                                        WinPrAsn1_tagId tagId, const char* msg)
{
  const BOOL rc = nla_write_octet_string(enc, buffer, tagId, msg);
  sspi_SecBufferFree(buffer);
  return rc;
}

/**
 * Send CredSSP message.
 *
 * @param nla A pointer to the NLA to use
 *
 * @return \b TRUE for success, \b FALSE otherwise
 */

BOOL nla_send(rdpNla* nla)
{
  BOOL rc = FALSE;
  wStream* s = NULL;
  size_t length = 0;
  WinPrAsn1Encoder* enc = NULL;

  WINPR_ASSERT(nla);

  enc = WinPrAsn1Encoder_New(WINPR_ASN1_DER);
  if (!enc)
    return FALSE;

  /* TSRequest */
  WLog_DBG(TAG, "----->> sending...");
  if (!WinPrAsn1EncSeqContainer(enc))
    goto fail;

  /* version [0] INTEGER */
  WLog_DBG(TAG, "   ----->> protocol version %" PRIu32, nla->version);
  if (!WinPrAsn1EncContextualInteger(enc, 0, nla->version))
    goto fail;

  /* negoTokens [1] SEQUENCE OF SEQUENCE */
  if (nla_get_state(nla) <= NLA_STATE_NEGO_TOKEN && credssp_auth_have_output_token(nla->auth))
  {
    const SecBuffer* buffer = credssp_auth_get_output_buffer(nla->auth);

    if (!WinPrAsn1EncContextualSeqContainer(enc, 1) || !WinPrAsn1EncSeqContainer(enc))
      goto fail;

    /* negoToken [0] OCTET STRING */
    if (!nla_write_octet_string(enc, buffer, 0, "negoToken"))
      goto fail;

    /* End negoTokens (SEQUENCE OF SEQUENCE) */
    if (!WinPrAsn1EncEndContainer(enc) || !WinPrAsn1EncEndContainer(enc))
      goto fail;
  }

  /* authInfo [2] OCTET STRING */
  if (nla->authInfo.cbBuffer > 0)
  {
    if (!nla_write_octet_string_free(enc, &nla->authInfo, 2, "auth info"))
      goto fail;
  }

  /* pubKeyAuth [3] OCTET STRING */
  if (nla->pubKeyAuth.cbBuffer > 0)
  {
    if (!nla_write_octet_string_free(enc, &nla->pubKeyAuth, 3, "public key auth"))
      goto fail;
  }

  /* errorCode [4] INTEGER */
  if (nla->errorCode && nla->peerVersion >= 3 && nla->peerVersion != 5)
  {
    WLog_DBG(TAG, "   ----->> error code %s 0x%08" PRIx32, NtStatus2Tag(nla->errorCode),
             nla->errorCode);
    if (!WinPrAsn1EncContextualInteger(enc, 4, nla->errorCode))
      goto fail;
  }

  /* clientNonce [5] OCTET STRING */
  if (!nla->server && nla->ClientNonce.cbBuffer > 0)
  {
    if (!nla_write_octet_string(enc, &nla->ClientNonce, 5, "client nonce"))
      goto fail;
  }

  /* End TSRequest */
  if (!WinPrAsn1EncEndContainer(enc))
    goto fail;

  if (!WinPrAsn1EncStreamSize(enc, &length))
    goto fail;

  s = Stream_New(NULL, length);
  if (!s)
    goto fail;

  if (!WinPrAsn1EncToStream(enc, s))
    goto fail;

  WLog_DBG(TAG, "[%" PRIuz " bytes]", length);
  if (transport_write(nla->transport, s) < 0)
    goto fail;
  rc = TRUE;

fail:
  Stream_Free(s, TRUE);
  WinPrAsn1Encoder_Free(&enc);
  return rc;
}

static int nla_decode_ts_request(rdpNla* nla, wStream* s)
{
  WinPrAsn1Decoder dec = { 0 };
  WinPrAsn1Decoder dec2 = { 0 };
  BOOL error = FALSE;
  WinPrAsn1_tagId tag = { 0 };
  WinPrAsn1_INTEGER val = { 0 };
  UINT32 version = 0;

  WINPR_ASSERT(nla);
  WINPR_ASSERT(s);

  WinPrAsn1Decoder_Init(&dec, WINPR_ASN1_DER, s);

  WLog_DBG(TAG, "<<----- receiving...");

  /* TSRequest */
  const size_t offset = WinPrAsn1DecReadSequence(&dec, &dec2);
  if (offset == 0)
    return -1;
  dec = dec2;

  /* version [0] INTEGER */
  if (WinPrAsn1DecReadContextualInteger(&dec, 0, &error, &val) == 0)
    return -1;

  if (!Stream_SafeSeek(s, offset))
    return -1;

  version = (UINT)val;
  WLog_DBG(TAG, "   <<----- protocol version %" PRIu32, version);

  if (nla->peerVersion == 0)
    nla->peerVersion = version;

  /* if the peer suddenly changed its version - kick it */
  if (nla->peerVersion != version)
  {
    WLog_ERR(TAG, "CredSSP peer changed protocol version from %" PRIu32 " to %" PRIu32,
             nla->peerVersion, version);
    return -1;
  }

  while (WinPrAsn1DecReadContextualTag(&dec, &tag, &dec2) != 0)
  {
    WinPrAsn1Decoder dec3 = { 0 };
    WinPrAsn1_OctetString octet_string = { 0 };

    switch (tag)
    {
      case 1:
        WLog_DBG(TAG, "   <<----- nego token");
        /* negoTokens [1] SEQUENCE OF SEQUENCE */
        if ((WinPrAsn1DecReadSequence(&dec2, &dec3) == 0) ||
            (WinPrAsn1DecReadSequence(&dec3, &dec2) == 0))
          return -1;
        /* negoToken [0] OCTET STRING */
        if ((WinPrAsn1DecReadContextualOctetString(&dec2, 0, &error, &octet_string,
                                                   FALSE) == 0) &&
            error)
          return -1;
        if (!nla_sec_buffer_alloc_from_data(&nla->negoToken, octet_string.data, 0,
                                            octet_string.len))
          return -1;
        break;
      case 2:
        WLog_DBG(TAG, "   <<----- auth info");
        /* authInfo [2] OCTET STRING */
        if (WinPrAsn1DecReadOctetString(&dec2, &octet_string, FALSE) == 0)
          return -1;
        if (!nla_sec_buffer_alloc_from_data(&nla->authInfo, octet_string.data, 0,
                                            octet_string.len))
          return -1;
        break;
      case 3:
        WLog_DBG(TAG, "   <<----- public key auth");
        /* pubKeyAuth [3] OCTET STRING */
        if (WinPrAsn1DecReadOctetString(&dec2, &octet_string, FALSE) == 0)
          return -1;
        if (!nla_sec_buffer_alloc_from_data(&nla->pubKeyAuth, octet_string.data, 0,
                                            octet_string.len))
          return -1;
        break;
      case 4:
        /* errorCode [4] INTEGER */
        if (WinPrAsn1DecReadInteger(&dec2, &val) == 0)
          return -1;
        nla->errorCode = (UINT)val;
        WLog_DBG(TAG, "   <<----- error code %s 0x%08" PRIx32, NtStatus2Tag(nla->errorCode),
                 nla->errorCode);
        break;
      case 5:
        WLog_DBG(TAG, "   <<----- client nonce");
        /* clientNonce [5] OCTET STRING */
        if (WinPrAsn1DecReadOctetString(&dec2, &octet_string, FALSE) == 0)
          return -1;
        if (!nla_sec_buffer_alloc_from_data(&nla->ClientNonce, octet_string.data, 0,
                                            octet_string.len))
          return -1;
        break;
      default:
        return -1;
    }
  }

  return 1;
}

int nla_recv_pdu(rdpNla* nla, wStream* s)
{
  WINPR_ASSERT(nla);
  WINPR_ASSERT(s);

  if (nla_get_state(nla) == NLA_STATE_EARLY_USER_AUTH)
  {
    UINT32 code = 0;
    Stream_Read_UINT32(s, code);
    if (code != AUTHZ_SUCCESS)
    {
      WLog_DBG(TAG, "Early User Auth active: FAILURE code 0x%08" PRIX32 "", code);
      code = FREERDP_ERROR_AUTHENTICATION_FAILED;
      freerdp_set_last_error_log(nla->rdpcontext, code);
      return -1;
    }
    else
      WLog_DBG(TAG, "Early User Auth active: SUCCESS");
  }
  else
  {
    if (nla_decode_ts_request(nla, s) < 1)
      return -1;

    if (nla->errorCode)
    {
      UINT32 code = 0;

      switch (nla->errorCode)
      {
        case STATUS_PASSWORD_MUST_CHANGE:
          code = FREERDP_ERROR_CONNECT_PASSWORD_MUST_CHANGE;
          break;

        case STATUS_PASSWORD_EXPIRED:
          code = FREERDP_ERROR_CONNECT_PASSWORD_EXPIRED;
          break;

        case STATUS_ACCOUNT_DISABLED:
          code = FREERDP_ERROR_CONNECT_ACCOUNT_DISABLED;
          break;

        case STATUS_LOGON_FAILURE:
          code = FREERDP_ERROR_CONNECT_LOGON_FAILURE;
          break;

        case STATUS_WRONG_PASSWORD:
          code = FREERDP_ERROR_CONNECT_WRONG_PASSWORD;
          break;

        case STATUS_ACCESS_DENIED:
          code = FREERDP_ERROR_CONNECT_ACCESS_DENIED;
          break;

        case STATUS_ACCOUNT_RESTRICTION:
          code = FREERDP_ERROR_CONNECT_ACCOUNT_RESTRICTION;
          break;

        case STATUS_ACCOUNT_LOCKED_OUT:
          code = FREERDP_ERROR_CONNECT_ACCOUNT_LOCKED_OUT;
          break;

        case STATUS_ACCOUNT_EXPIRED:
          code = FREERDP_ERROR_CONNECT_ACCOUNT_EXPIRED;
          break;

        case STATUS_LOGON_TYPE_NOT_GRANTED:
          code = FREERDP_ERROR_CONNECT_LOGON_TYPE_NOT_GRANTED;
          break;

        default:
          WLog_ERR(TAG, "SPNEGO failed with NTSTATUS: %s [0x%08" PRIX32 "]",
                   NtStatus2Tag(nla->errorCode), nla->errorCode);
          code = FREERDP_ERROR_AUTHENTICATION_FAILED;
          break;
      }

      freerdp_set_last_error_log(nla->rdpcontext, code);
      return -1;
    }
  }

  return nla_client_recv(nla);
}

int nla_server_recv(rdpNla* nla)
{
  int status = -1;

  WINPR_ASSERT(nla);

  wStream* s = nla_server_recv_stream(nla);
  if (!s)
    goto fail;
  status = nla_decode_ts_request(nla, s);

fail:
  Stream_Free(s, TRUE);
  return status;
}

/**
 * Create new CredSSP state machine.
 *
 * @param context A pointer to the rdp context to use
 * @param transport A pointer to the transport to use
 *
 * @return new CredSSP state machine.
 */

rdpNla* nla_new(rdpContext* context, rdpTransport* transport)
{
  WINPR_ASSERT(transport);
  WINPR_ASSERT(context);

  rdpSettings* settings = context->settings;
  WINPR_ASSERT(settings);

  rdpNla* nla = (rdpNla*)calloc(1, sizeof(rdpNla));

  if (!nla)
    return NULL;

  nla->rdpcontext = context;
  nla->server = settings->ServerMode;
  nla->transport = transport;
  nla->sendSeqNum = 0;
  nla->recvSeqNum = 0;
  nla->version = 6;
  nla->earlyUserAuth = FALSE;

  nla->identity = calloc(1, sizeof(SEC_WINNT_AUTH_IDENTITY));
  if (!nla->identity)
    goto cleanup;

  nla->auth = credssp_auth_new(context);
  if (!nla->auth)
    goto cleanup;

  /* init to 0 or we end up freeing a bad pointer if the alloc fails */
  if (!nla_sec_buffer_alloc(&nla->ClientNonce, NonceLength))
    goto cleanup;

  /* generate random 32-byte nonce */
  if (winpr_RAND(nla->ClientNonce.pvBuffer, NonceLength) < 0)
    goto cleanup;

  return nla;
cleanup:
  WINPR_PRAGMA_DIAG_PUSH
  WINPR_PRAGMA_DIAG_IGNORED_MISMATCHED_DEALLOC
  nla_free(nla);
  WINPR_PRAGMA_DIAG_POP
  return NULL;
}

/**
 * Free CredSSP state machine.
 * @param nla The NLA instance to free
 */

void nla_free(rdpNla* nla)
{
  if (!nla)
    return;

  smartcardCertInfo_Free(nla->smartcardCert);
  nla_buffer_free(nla);
  sspi_SecBufferFree(&nla->tsCredentials);
  credssp_auth_free(nla->auth);

  sspi_FreeAuthIdentity(nla->identity);
  free(nla->pkinitArgs);
  free(nla->identity);
  free(nla);
}

SEC_WINNT_AUTH_IDENTITY* nla_get_identity(rdpNla* nla)
{
  if (!nla)
    return NULL;

  return nla->identity;
}

NLA_STATE nla_get_state(rdpNla* nla)
{
  if (!nla)
    return NLA_STATE_FINAL;

  return nla->state;
}

BOOL nla_set_state(rdpNla* nla, NLA_STATE state)
{
  if (!nla)
    return FALSE;

  WLog_DBG(TAG, "-- %s\t--> %s", nla_get_state_str(nla->state), nla_get_state_str(state));
  nla->state = state;
  return TRUE;
}

BOOL nla_set_service_principal(rdpNla* nla, const char* service, const char* hostname)
{
  if (!credssp_auth_set_spn(nla->auth, service, hostname))
    return FALSE;
  return TRUE;
}

BOOL nla_impersonate(rdpNla* nla)
{
  return credssp_auth_impersonate(nla->auth);
}

BOOL nla_revert_to_self(rdpNla* nla)
{
  return credssp_auth_revert_to_self(nla->auth);
}

const char* nla_get_state_str(NLA_STATE state)
{
  switch (state)
  {
    case NLA_STATE_INITIAL:
      return "NLA_STATE_INITIAL";
    case NLA_STATE_NEGO_TOKEN:
      return "NLA_STATE_NEGO_TOKEN";
    case NLA_STATE_PUB_KEY_AUTH:
      return "NLA_STATE_PUB_KEY_AUTH";
    case NLA_STATE_AUTH_INFO:
      return "NLA_STATE_AUTH_INFO";
    case NLA_STATE_POST_NEGO:
      return "NLA_STATE_POST_NEGO";
    case NLA_STATE_EARLY_USER_AUTH:
      return "NLA_STATE_EARLY_USER_AUTH";
    case NLA_STATE_FINAL:
      return "NLA_STATE_FINAL";
    default:
      return "UNKNOWN";
  }
}

DWORD nla_get_error(rdpNla* nla)
{
  if (!nla)
    return ERROR_INTERNAL_ERROR;
  return nla->errorCode;
}

UINT32 nla_get_sspi_error(rdpNla* nla)
{
  WINPR_ASSERT(nla);
  return credssp_auth_sspi_error(nla->auth);
}

Coverage Report

Created: 2024-09-08 06:20