/src/FreeRDP/winpr/libwinpr/sspi/Negotiate/negotiate.c

Source
/**
 * WinPR: Windows Portable Runtime
 * Negotiate Security Package
 *
 * Copyright 2011-2014 Marc-Andre Moreau <marcandre.moreau@gmail.com>
 * Copyright 2017 Dorian Ducournau <dorian.ducournau@gmail.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <winpr/config.h>

#include <winpr/crt.h>
#include <winpr/wtypes.h>
#include <winpr/assert.h>
#include <winpr/sspi.h>
#include <winpr/tchar.h>
#if !defined(WITHOUT_WINPR_3x_DEPRECATED)
#include <winpr/registry.h>
#endif
#include <winpr/build-config.h>
#include <winpr/asn1.h>
#include <winpr/path.h>
#include <winpr/config-readers.h>

#include "negotiate.h"

#include "../NTLM/ntlm.h"
#include "../NTLM/ntlm_export.h"
#include "../Kerberos/kerberos.h"
#include "../sspi.h"
#include "../../utils.h"
#include "../../log.h"
#define TAG WINPR_TAG("negotiate")

#if !defined(WITHOUT_WINPR_3x_DEPRECATED)
#define NEGO_REG_KEY "Software\\%s\\SSPI\\Negotiate"
#endif

static const char PACKAGE_NAME_DISABLE_ALL[] = "none";
static const char PACKAGE_NAME_NTLM[] = "ntlm";
static const char PACKAGE_NAME_KERBEROS[] = "kerberos";
static const char PACKAGE_NAME_KERBEROS_U2U[] = "u2u";

typedef struct
{
  const TCHAR* name;
  const SecurityFunctionTableA* table;
  const SecurityFunctionTableW* table_w;
} SecPkg;

struct Mech_st
{
  const WinPrAsn1_OID* oid;
  const SecPkg* pkg;
  const UINT flags;
  const BOOL preferred;
};

typedef struct
{
  const Mech* mech;
  CredHandle cred;
  BOOL valid;
} MechCred;

const SecPkgInfoA NEGOTIATE_SecPkgInfoA = {
  0x00083BB3,                    /* fCapabilities */
  1,                             /* wVersion */
  0x0009,                        /* wRPCID */
  0x00002FE0,                    /* cbMaxToken */
  "Negotiate",                   /* Name */
  "Microsoft Package Negotiator" /* Comment */
};

static WCHAR NEGOTIATE_SecPkgInfoW_NameBuffer[32] = WINPR_C_ARRAY_INIT;
static WCHAR NEGOTIATE_SecPkgInfoW_CommentBuffer[32] = WINPR_C_ARRAY_INIT;

const SecPkgInfoW NEGOTIATE_SecPkgInfoW = {
  0x00083BB3,                         /* fCapabilities */
  1,                                  /* wVersion */
  0x0009,                             /* wRPCID */
  0x00002FE0,                         /* cbMaxToken */
  NEGOTIATE_SecPkgInfoW_NameBuffer,   /* Name */
  NEGOTIATE_SecPkgInfoW_CommentBuffer /* Comment */
};

static const WinPrAsn1_OID spnego_OID = { 6, (BYTE*)"\x2b\x06\x01\x05\x05\x02" };
static const WinPrAsn1_OID kerberos_u2u_OID = { 10,
                                              (BYTE*)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x03" };
static const WinPrAsn1_OID kerberos_OID = { 9, (BYTE*)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" };
static const WinPrAsn1_OID kerberos_wrong_OID = { 9,
                                                (BYTE*)"\x2a\x86\x48\x82\xf7\x12\x01\x02\x02" };
static const WinPrAsn1_OID ntlm_OID = { 10, (BYTE*)"\x2b\x06\x01\x04\x01\x82\x37\x02\x02\x0a" };

static const WinPrAsn1_OID negoex_OID = { 10, (BYTE*)"\x2b\x06\x01\x04\x01\x82\x37\x02\x02\x1e" };

#ifdef WITH_KRB5
static const SecPkg SecPkgTable[] = {
  { KERBEROS_SSP_NAME, &KERBEROS_SecurityFunctionTableA, &KERBEROS_SecurityFunctionTableW },
  { KERBEROS_SSP_NAME, &KERBEROS_SecurityFunctionTableA, &KERBEROS_SecurityFunctionTableW },
  { NTLM_SSP_NAME, &NTLM_SecurityFunctionTableA, &NTLM_SecurityFunctionTableW }
};

static const Mech MechTable[] = {
  { &kerberos_u2u_OID, &SecPkgTable[0], ISC_REQ_INTEGRITY | ISC_REQ_USE_SESSION_KEY, TRUE },
  { &kerberos_OID, &SecPkgTable[1], ISC_REQ_INTEGRITY, TRUE },
  { &ntlm_OID, &SecPkgTable[2], 0, FALSE },
};
#else
static const SecPkg SecPkgTable[] = { { NTLM_SSP_NAME, &NTLM_SecurityFunctionTableA,
                                      &NTLM_SecurityFunctionTableW } };

static const Mech MechTable[] = {
  { &ntlm_OID, &SecPkgTable[0], 0, FALSE },
};
#endif

static const size_t MECH_COUNT = ARRAYSIZE(MechTable);

enum NegState
{
  NOSTATE = -1,
  ACCEPT_COMPLETED,
  ACCEPT_INCOMPLETE,
  REJECT,
  REQUEST_MIC
};

typedef struct
{
  enum NegState negState;
  BOOL init;
  WinPrAsn1_OID supportedMech;
  SecBuffer mechTypes;
  SecBuffer mechToken;
  SecBuffer mic;
} NegToken;

static const NegToken empty_neg_token = { NOSTATE,           FALSE,
                                        { 0, nullptr },    { 0, 0, nullptr },
                                        { 0, 0, nullptr }, { 0, 0, nullptr } };

static NEGOTIATE_CONTEXT* negotiate_ContextNew(NEGOTIATE_CONTEXT* init_context)
{
  NEGOTIATE_CONTEXT* context = nullptr;

  WINPR_ASSERT(init_context);

  context = calloc(1, sizeof(NEGOTIATE_CONTEXT));
  if (!context)
    return nullptr;

  if (init_context->spnego)
  {
    init_context->mechTypes.pvBuffer = malloc(init_context->mechTypes.cbBuffer);
    if (!init_context->mechTypes.pvBuffer)
    {
      free(context);
      return nullptr;
    }
  }

  *context = *init_context;

  return context;
}

static void negotiate_ContextFree(NEGOTIATE_CONTEXT* context)
{
  WINPR_ASSERT(context);

  if (context->mechTypes.pvBuffer)
    free(context->mechTypes.pvBuffer);
  free(context);
}

static const char* negotiate_mech_name(const WinPrAsn1_OID* oid)
{
  if (sspi_gss_oid_compare(oid, &spnego_OID))
    return "SPNEGO (1.3.6.1.5.5.2)";
  else if (sspi_gss_oid_compare(oid, &kerberos_u2u_OID))
    return "Kerberos user to user (1.2.840.113554.1.2.2.3)";
  else if (sspi_gss_oid_compare(oid, &kerberos_OID))
    return "Kerberos (1.2.840.113554.1.2.2)";
  else if (sspi_gss_oid_compare(oid, &kerberos_wrong_OID))
    return "Kerberos [wrong OID] (1.2.840.48018.1.2.2)";
  else if (sspi_gss_oid_compare(oid, &ntlm_OID))
    return "NTLM (1.3.6.1.4.1.311.2.2.10)";
  else if (sspi_gss_oid_compare(oid, &negoex_OID))
    return "NegoEx (1.3.6.1.4.1.311.2.2.30)";
  else
    return "Unknown mechanism";
}

static const Mech* negotiate_GetMechByOID(const WinPrAsn1_OID* oid)
{
  WINPR_ASSERT(oid);

  WinPrAsn1_OID testOid = *oid;

  if (sspi_gss_oid_compare(&testOid, &kerberos_wrong_OID))
  {
    testOid.len = kerberos_OID.len;
    testOid.data = kerberos_OID.data;
  }

  for (size_t i = 0; i < MECH_COUNT; i++)
  {
    if (sspi_gss_oid_compare(&testOid, MechTable[i].oid))
      return &MechTable[i];
  }
  return nullptr;
}

static PSecHandle negotiate_FindCredential(MechCred* creds, const Mech* mech)
{
  WINPR_ASSERT(creds);

  if (!mech)
    return nullptr;

  for (size_t i = 0; i < MECH_COUNT; i++)
  {
    MechCred* cred = &creds[i];

    if (cred->mech == mech)
    {
      if (cred->valid)
        return &cred->cred;
      return nullptr;
    }
  }

  return nullptr;
}

#if !defined(WITHOUT_WINPR_3x_DEPRECATED)
static BOOL negotiate_get_dword(HKEY hKey, const char* subkey, DWORD* pdwValue)
{
  DWORD dwValue = 0;
  DWORD dwType = 0;
  DWORD dwSize = sizeof(dwValue);
  LONG rc = RegQueryValueExA(hKey, subkey, nullptr, &dwType, (BYTE*)&dwValue, &dwSize);

  if (rc != ERROR_SUCCESS)
    return FALSE;
  if (dwType != REG_DWORD)
    return FALSE;

  *pdwValue = dwValue;
  return TRUE;
}
#endif

static BOOL negotiate_get_config_from_auth_package_list(void* pAuthData, BOOL* kerberos, BOOL* ntlm,
                                                        BOOL* u2u)
{
  BOOL rc = FALSE;
  char* tok_ctx = nullptr;
  char* PackageList = nullptr;

  if (!sspi_CopyAuthPackageListA((const SEC_WINNT_AUTH_IDENTITY_INFO*)pAuthData, &PackageList))
    return FALSE;

  char* tok_ptr = strtok_s(PackageList, ",", &tok_ctx);

  while (tok_ptr)
  {
    const char* PackageName = tok_ptr;
    BOOL PackageInclude = TRUE;

    if (PackageName[0] == '!')
    {
      PackageName = &PackageName[1];
      PackageInclude = FALSE;
    }

    if (_stricmp(PackageName, PACKAGE_NAME_NTLM) == 0)
    {
      *ntlm = PackageInclude;
    }
    else if (_stricmp(PackageName, PACKAGE_NAME_KERBEROS) == 0)
    {
      *kerberos = PackageInclude;
    }
    else if (_stricmp(PackageName, PACKAGE_NAME_KERBEROS_U2U) == 0)
    {
      *u2u = PackageInclude;
    }
    else if (_stricmp(PackageName, PACKAGE_NAME_DISABLE_ALL) == 0)
    {
      *kerberos = FALSE;
      *ntlm = FALSE;
      *u2u = FALSE;

      if (PackageName != PackageList)
      {
        WLog_WARN(TAG, "Special keyword '%s' not first in list, aborting", PackageName);
        goto fail;
      }
    }
    else
    {
      WLog_WARN(TAG, "Unknown authentication package name: %s, ignoring", PackageName);
    }

    tok_ptr = strtok_s(nullptr, ",", &tok_ctx);
  }

  rc = TRUE;
fail:
  free(PackageList);
  return rc;
}

static BOOL negotiate_get_config(void* pAuthData, BOOL* kerberos, BOOL* ntlm, BOOL* u2u)
{
  WINPR_ASSERT(kerberos);
  WINPR_ASSERT(ntlm);
  WINPR_ASSERT(u2u);

#if !defined(WITH_KRB5_NO_NTLM_FALLBACK)
  *ntlm = TRUE;
#else
  *ntlm = FALSE;
#endif
#if defined(WITH_KRB5)
  *kerberos = TRUE;
  *u2u = TRUE;
#else
  *kerberos = FALSE;
  *u2u = FALSE;
#endif

  if (negotiate_get_config_from_auth_package_list(pAuthData, kerberos, ntlm, u2u))
  {
    return TRUE; // use explicit authentication package list
  }

  const char config[] = "negotiate.json";

#if !defined(WITHOUT_WINPR_3x_DEPRECATED)
  {
    char* key = winpr_getApplicatonDetailsRegKey(NEGO_REG_KEY);
    if (key)
    {
      HKEY hKey = nullptr;
      const LONG rc =
          RegOpenKeyExA(HKEY_LOCAL_MACHINE, key, 0, KEY_READ | KEY_WOW64_64KEY, &hKey);
      free(key);
      if (rc == ERROR_SUCCESS)
      {
        WLog_WARN(TAG, "HKLM.reg is deprecated since 3.33.0. ATTENTION: Use %s instead!",
                  config);

        DWORD dwValue = 0;

        if (negotiate_get_dword(hKey, PACKAGE_NAME_KERBEROS, &dwValue))
          *kerberos = (dwValue != 0);

        if (negotiate_get_dword(hKey, PACKAGE_NAME_KERBEROS_U2U, &dwValue))
          *u2u = (dwValue != 0);

#if !defined(WITH_KRB5_NO_NTLM_FALLBACK)
        if (negotiate_get_dword(hKey, PACKAGE_NAME_NTLM, &dwValue))
          *ntlm = (dwValue != 0);
#endif

        RegCloseKey(hKey);
      }
    }
  }
#endif

  WINPR_JSON* json = winpr_GetJSONConfigFile(TRUE, config);
  if (json)
  {
    winpr_config_apply_bool(config, json, PACKAGE_NAME_KERBEROS, kerberos);
    winpr_config_apply_bool(config, json, PACKAGE_NAME_KERBEROS_U2U, u2u);
#if !defined(WITH_KRB5_NO_NTLM_FALLBACK)
    winpr_config_apply_bool(config, json, PACKAGE_NAME_NTLM, ntlm);
#endif
    WINPR_JSON_Delete(json);
  }

  return TRUE;
}

static BOOL negotiate_write_neg_token(PSecBuffer output_buffer, NegToken* token)
{
  WINPR_ASSERT(output_buffer);
  WINPR_ASSERT(token);

  BOOL ret = FALSE;
  WinPrAsn1Encoder* enc = nullptr;
  WinPrAsn1_MemoryChunk mechTypes = { token->mechTypes.cbBuffer, token->mechTypes.pvBuffer };
  WinPrAsn1_OctetString mechToken = { token->mechToken.cbBuffer, token->mechToken.pvBuffer };
  WinPrAsn1_OctetString mechListMic = { token->mic.cbBuffer, token->mic.pvBuffer };
  wStream s;
  size_t len = 0;

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

  /* For NegTokenInit wrap in an initialContextToken */
  if (token->init)
  {
    /* InitialContextToken [APPLICATION 0] IMPLICIT SEQUENCE */
    if (!WinPrAsn1EncAppContainer(enc, 0))
      goto cleanup;

    /* thisMech MechType OID */
    if (!WinPrAsn1EncOID(enc, &spnego_OID))
      goto cleanup;
  }

  /* innerContextToken [0] NegTokenInit or [1] NegTokenResp */
  if (!WinPrAsn1EncContextualSeqContainer(enc, token->init ? 0 : 1))
    goto cleanup;

  WLog_DBG(TAG, token->init ? "Writing negTokenInit..." : "Writing negTokenResp...");

  /* mechTypes [0] MechTypeList (mechTypes already contains the SEQUENCE tag) */
  if (token->init)
  {
    if (!WinPrAsn1EncContextualRawContent(enc, 0, &mechTypes))
      goto cleanup;
    WLog_DBG(TAG, "\tmechTypes [0] (%" PRIu32 " bytes)", token->mechTypes.cbBuffer);
  }
  /* negState [0] ENUMERATED */
  else if (token->negState != NOSTATE)
  {
    if (!WinPrAsn1EncContextualEnumerated(enc, 0, token->negState))
      goto cleanup;
    WLog_DBG(TAG, "\tnegState [0] (%d)", token->negState);
  }

  /* supportedMech [1] OID */
  if (token->supportedMech.len)
  {
    if (!WinPrAsn1EncContextualOID(enc, 1, &token->supportedMech))
      goto cleanup;
    WLog_DBG(TAG, "\tsupportedMech [1] (%s)", negotiate_mech_name(&token->supportedMech));
  }

  /* mechToken [2] OCTET STRING */
  if (token->mechToken.cbBuffer)
  {
    if (WinPrAsn1EncContextualOctetString(enc, 2, &mechToken) == 0)
      goto cleanup;
    WLog_DBG(TAG, "\tmechToken [2] (%" PRIu32 " bytes)", token->mechToken.cbBuffer);
  }

  /* mechListMIC [3] OCTET STRING */
  if (token->mic.cbBuffer)
  {
    if (WinPrAsn1EncContextualOctetString(enc, 3, &mechListMic) == 0)
      goto cleanup;
    WLog_DBG(TAG, "\tmechListMIC [3] (%" PRIu32 " bytes)", token->mic.cbBuffer);
  }

  /* NegTokenInit or NegTokenResp */
  if (!WinPrAsn1EncEndContainer(enc))
    goto cleanup;

  if (token->init)
  {
    /* initialContextToken */
    if (!WinPrAsn1EncEndContainer(enc))
      goto cleanup;
  }

  if (!WinPrAsn1EncStreamSize(enc, &len) || len > output_buffer->cbBuffer)
    goto cleanup;

  if (len > UINT32_MAX)
    goto cleanup;

  Stream_StaticInit(&s, output_buffer->pvBuffer, len);

  if (WinPrAsn1EncToStream(enc, &s))
  {
    output_buffer->cbBuffer = (UINT32)len;
    ret = TRUE;
  }

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

static BOOL negotiate_read_neg_token(PSecBuffer input, NegToken* token)
{
  WinPrAsn1Decoder dec = WinPrAsn1Decoder_init();
  WinPrAsn1Decoder dec2 = WinPrAsn1Decoder_init();
  WinPrAsn1_OID oid = WINPR_C_ARRAY_INIT;
  WinPrAsn1_tagId contextual = 0;
  WinPrAsn1_tag tag = 0;
  size_t len = 0;
  WinPrAsn1_OctetString octet_string = WINPR_C_ARRAY_INIT;
  BOOL err = 0;

  WINPR_ASSERT(input);
  WINPR_ASSERT(token);

  WinPrAsn1Decoder_InitMem(&dec, WINPR_ASN1_DER, input->pvBuffer, input->cbBuffer);

  if (!WinPrAsn1DecPeekTag(&dec, &tag))
    return FALSE;

  if (tag == 0x60)
  {
    /* initialContextToken [APPLICATION 0] */
    if (!WinPrAsn1DecReadApp(&dec, &tag, &dec2) || tag != 0)
      return FALSE;
    dec = dec2;

    /* thisMech OID */
    if (!WinPrAsn1DecReadOID(&dec, &oid, FALSE))
      return FALSE;

    if (!sspi_gss_oid_compare(&spnego_OID, &oid))
      return FALSE;

    /* [0] NegTokenInit */
    if (!WinPrAsn1DecReadContextualSequence(&dec, 0, &err, &dec2))
      return FALSE;

    token->init = TRUE;
  }
  /* [1] NegTokenResp */
  else if (!WinPrAsn1DecReadContextualSequence(&dec, 1, &err, &dec2))
    return FALSE;
  dec = dec2;

  WLog_DBG(TAG, token->init ? "Reading negTokenInit..." : "Reading negTokenResp...");

  /* Read NegTokenResp sequence members */
  do
  {
    if (!WinPrAsn1DecReadContextualTag(&dec, &contextual, &dec2))
      return FALSE;

    switch (contextual)
    {
      case 0:
        if (token->init)
        {
          /* mechTypes [0] MechTypeList */
          wStream s = WinPrAsn1DecGetStream(&dec2);
          token->mechTypes.BufferType = SECBUFFER_TOKEN;
          const size_t mlen = Stream_Length(&s);
          if (mlen > UINT32_MAX)
            return FALSE;
          token->mechTypes.cbBuffer = (UINT32)mlen;
          token->mechTypes.pvBuffer = Stream_Buffer(&s);
          WLog_DBG(TAG, "\tmechTypes [0] (%" PRIu32 " bytes)", token->mechTypes.cbBuffer);
        }
        else
        {
          /* negState [0] ENUMERATED */
          WinPrAsn1_ENUMERATED rd = 0;
          if (!WinPrAsn1DecReadEnumerated(&dec2, &rd))
            return FALSE;
          switch (rd)
          {
            case NOSTATE:
            case ACCEPT_COMPLETED:
            case ACCEPT_INCOMPLETE:
            case REJECT:
            case REQUEST_MIC:
              break;
            default:
              WLog_ERR(TAG, "Invalid negState enumeration value %d", rd);
              return FALSE;
          }

          token->negState = WINPR_ASSERTING_INT_CAST(enum NegState, rd);
          WLog_DBG(TAG, "\tnegState [0] (%d)", rd);
        }
        break;
      case 1:
        if (token->init)
        {
          /* reqFlags [1] ContextFlags BIT STRING (ignored) */
          if (!WinPrAsn1DecPeekTagAndLen(&dec2, &tag, &len) || (tag != ER_TAG_BIT_STRING))
            return FALSE;
          WLog_DBG(TAG, "\treqFlags [1] (%" PRIuz " bytes)", len);
        }
        else
        {
          /* supportedMech [1] MechType */
          if (!WinPrAsn1DecReadOID(&dec2, &token->supportedMech, FALSE))
            return FALSE;
          WLog_DBG(TAG, "\tsupportedMech [1] (%s)",
                   negotiate_mech_name(&token->supportedMech));
        }
        break;
      case 2:
        /* mechToken [2] OCTET STRING */
        if (!WinPrAsn1DecReadOctetString(&dec2, &octet_string, FALSE))
          return FALSE;
        if (octet_string.len > UINT32_MAX)
          return FALSE;
        token->mechToken.cbBuffer = (UINT32)octet_string.len;
        token->mechToken.pvBuffer = octet_string.data;
        token->mechToken.BufferType = SECBUFFER_TOKEN;
        WLog_DBG(TAG, "\tmechToken [2] (%" PRIuz " bytes)", octet_string.len);
        break;
      case 3:
        /* mechListMic [3] OCTET STRING */
        if (!WinPrAsn1DecReadOctetString(&dec2, &octet_string, FALSE))
          return FALSE;
        if (octet_string.len > UINT32_MAX)
          return FALSE;
        token->mic.cbBuffer = (UINT32)octet_string.len;
        token->mic.pvBuffer = octet_string.data;
        token->mic.BufferType = SECBUFFER_TOKEN;
        WLog_DBG(TAG, "\tmechListMIC [3] (%" PRIuz " bytes)", octet_string.len);
        break;
      default:
        WLog_ERR(TAG, "unknown contextual item %d", contextual);
        return FALSE;
    }
  } while (WinPrAsn1DecPeekTag(&dec, &tag));

  return TRUE;
}

static SECURITY_STATUS negotiate_mic_exchange(NEGOTIATE_CONTEXT* context, NegToken* input_token,
                                              NegToken* output_token, PSecBuffer output_buffer)
{
  SecBuffer mic_buffers[2] = WINPR_C_ARRAY_INIT;
  SecBufferDesc mic_buffer_desc = { SECBUFFER_VERSION, 2, mic_buffers };
  SECURITY_STATUS status = 0;

  WINPR_ASSERT(context);
  WINPR_ASSERT(input_token);
  WINPR_ASSERT(output_token);
  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);

  const SecurityFunctionTableA* table = context->mech->pkg->table;
  WINPR_ASSERT(table);

  mic_buffers[0] = context->mechTypes;

  /* Verify MIC if we received one */
  if (input_token->mic.cbBuffer > 0)
  {
    mic_buffers[1] = input_token->mic;

    status = table->VerifySignature(&context->sub_context, &mic_buffer_desc, 0, nullptr);
    if (status != SEC_E_OK)
      return status;

    output_token->negState = ACCEPT_COMPLETED;
  }

  /* If peer expects a MIC then generate it */
  if (input_token->negState != ACCEPT_COMPLETED)
  {
    /* Store the mic token after the mech token in the output buffer */
    output_token->mic.BufferType = SECBUFFER_TOKEN;
    if (output_buffer)
    {
      output_token->mic.cbBuffer = output_buffer->cbBuffer - output_token->mechToken.cbBuffer;
      output_token->mic.pvBuffer =
          (BYTE*)output_buffer->pvBuffer + output_token->mechToken.cbBuffer;
    }
    mic_buffers[1] = output_token->mic;

    status = table->MakeSignature(&context->sub_context, 0, &mic_buffer_desc, 0);
    if (status != SEC_E_OK)
      return status;

    output_token->mic = mic_buffers[1];
  }

  /* When using NTLM cipher states need to be reset after mic exchange */
  const SSPI_PACKAGE_ID sub_id = sspi_SecureHandleGetPackageId(&context->sub_context);
  if (!sub_id)
    return SEC_E_INTERNAL_ERROR;

  if (sub_id == SSPI_PACKAGE_NTLM)
  {
    if (!ntlm_reset_cipher_state(&context->sub_context))
      return SEC_E_INTERNAL_ERROR;
  }

  return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY negotiate_InitializeSecurityContextW(
    PCredHandle phCredential, PCtxtHandle phContext, SEC_WCHAR* pszTargetName, ULONG fContextReq,
    ULONG Reserved1, ULONG TargetDataRep, PSecBufferDesc pInput, ULONG Reserved2,
    PCtxtHandle phNewContext, PSecBufferDesc pOutput, PULONG pfContextAttr, PTimeStamp ptsExpiry)
{
  NEGOTIATE_CONTEXT* context = nullptr;
  NEGOTIATE_CONTEXT init_context = NEGOTIATE_CONTEXT_init();
  MechCred* creds = nullptr;
  PCtxtHandle sub_context = nullptr;
  PCredHandle sub_cred = nullptr;
  NegToken input_token = empty_neg_token;
  NegToken output_token = empty_neg_token;
  PSecBuffer input_buffer = nullptr;
  PSecBuffer output_buffer = nullptr;
  PSecBuffer bindings_buffer = nullptr;
  SecBuffer mech_input_buffers[2] = WINPR_C_ARRAY_INIT;
  SecBufferDesc mech_input = { SECBUFFER_VERSION, 2, mech_input_buffers };
  SecBufferDesc mech_output = { SECBUFFER_VERSION, 1, &output_token.mechToken };
  SECURITY_STATUS status = SEC_E_INTERNAL_ERROR;
  SECURITY_STATUS sub_status = SEC_E_INTERNAL_ERROR;
  WinPrAsn1Encoder* enc = nullptr;
  wStream s;
  const Mech* mech = nullptr;

  if (!phCredential || !SecIsValidHandle(phCredential))
    return SEC_E_NO_CREDENTIALS;

  creds = sspi_SecureHandleGetLowerPointer(phCredential);

  /* behave like windows SSPIs that don't want empty context */
  if (phContext && !phContext->dwLower && !phContext->dwUpper)
    return SEC_E_INVALID_HANDLE;

  context = sspi_SecureHandleGetLowerPointer(phContext);

  if (pInput)
  {
    input_buffer = sspi_FindSecBuffer(pInput, SECBUFFER_TOKEN);
    bindings_buffer = sspi_FindSecBuffer(pInput, SECBUFFER_CHANNEL_BINDINGS);
  }
  if (pOutput)
    output_buffer = sspi_FindSecBuffer(pOutput, SECBUFFER_TOKEN);

  if (!context)
  {
    enc = WinPrAsn1Encoder_New(WINPR_ASN1_DER);
    if (!enc)
      return SEC_E_INSUFFICIENT_MEMORY;

    if (!WinPrAsn1EncSeqContainer(enc))
      goto cleanup;

    for (size_t i = 0; i < MECH_COUNT; i++)
    {
      MechCred* cred = &creds[i];
      const SecPkg* pkg = MechTable[i].pkg;
      WINPR_ASSERT(pkg);
      WINPR_ASSERT(pkg->table_w);

      if (!cred->valid)
      {
        WLog_DBG(TAG, "Unavailable mechanism: %s", negotiate_mech_name(cred->mech->oid));
        continue;
      }

      /* Send an optimistic token for the first valid mechanism */
      if (!init_context.mech)
      {
        /* Use the output buffer to store the optimistic token */
        if (!output_buffer)
          goto cleanup;

        CopyMemory(&output_token.mechToken, output_buffer, sizeof(SecBuffer));

        if (bindings_buffer)
          mech_input_buffers[0] = *bindings_buffer;

        WINPR_ASSERT(pkg->table_w->InitializeSecurityContextW);
        sub_status = pkg->table_w->InitializeSecurityContextW(
            &cred->cred, nullptr, pszTargetName, fContextReq | cred->mech->flags, Reserved1,
            TargetDataRep, &mech_input, Reserved2, &init_context.sub_context, &mech_output,
            pfContextAttr, ptsExpiry);

        /* If the mechanism failed we can't use it; skip */
        if (IsSecurityStatusError(sub_status))
        {
          if (SecIsValidHandle(&init_context.sub_context))
          {
            WINPR_ASSERT(pkg->table_w->DeleteSecurityContext);
            pkg->table_w->DeleteSecurityContext(&init_context.sub_context);
          }
          cred->valid = FALSE;
          continue;
        }

        init_context.mech = cred->mech;
      }

      if (!WinPrAsn1EncOID(enc, cred->mech->oid))
        goto cleanup;
      WLog_DBG(TAG, "Available mechanism: %s", negotiate_mech_name(cred->mech->oid));
    }

    /* No usable mechanisms were found */
    if (!init_context.mech)
      goto cleanup;

    /* If the only available mech is NTLM use it directly otherwise use spnego */
    if (init_context.mech->oid == &ntlm_OID)
    {
      init_context.spnego = FALSE;
      output_buffer->cbBuffer = output_token.mechToken.cbBuffer;
      WLog_DBG(TAG, "Using direct NTLM");
    }
    else
    {
      init_context.spnego = TRUE;
      init_context.mechTypes.BufferType = SECBUFFER_DATA;
      const size_t cb = WinPrAsn1EncEndContainer(enc);
      WINPR_ASSERT(cb <= UINT32_MAX);
      init_context.mechTypes.cbBuffer = (UINT32)cb;
    }

    /* Allocate memory for the new context */
    context = negotiate_ContextNew(&init_context);
    if (!context)
    {
      init_context.mech->pkg->table->DeleteSecurityContext(&init_context.sub_context);
      WinPrAsn1Encoder_Free(&enc);
      return SEC_E_INSUFFICIENT_MEMORY;
    }

    sspi_SecureHandleSetPackageId(phNewContext, SSPI_PACKAGE_NEGOTIATE);
    sspi_SecureHandleSetLowerPointer(phNewContext, context);

    if (!context->spnego)
    {
      status = sub_status;
      goto cleanup;
    }

    /* Write mechTypesList */
    Stream_StaticInit(&s, context->mechTypes.pvBuffer, context->mechTypes.cbBuffer);
    if (!WinPrAsn1EncToStream(enc, &s))
      goto cleanup;

    output_token.mechTypes.cbBuffer = context->mechTypes.cbBuffer;
    output_token.mechTypes.pvBuffer = context->mechTypes.pvBuffer;
    output_token.init = TRUE;

    if (sub_status == SEC_E_OK)
      context->state = NEGOTIATE_STATE_FINAL_OPTIMISTIC;
  }
  else
  {
    if (!input_buffer)
      return SEC_E_INVALID_TOKEN;

    sub_context = &context->sub_context;
    sub_cred = negotiate_FindCredential(creds, context->mech);

    if (!context->spnego)
    {
      return context->mech->pkg->table_w->InitializeSecurityContextW(
          sub_cred, sub_context, pszTargetName, fContextReq | context->mech->flags, Reserved1,
          TargetDataRep, pInput, Reserved2, sub_context, pOutput, pfContextAttr, ptsExpiry);
    }

    if (!negotiate_read_neg_token(input_buffer, &input_token))
      return SEC_E_INVALID_TOKEN;

    /* On first response check if the server doesn't like out preferred mech */
    if (context->state < NEGOTIATE_STATE_NEGORESP && input_token.supportedMech.len &&
        !sspi_gss_oid_compare(&input_token.supportedMech, context->mech->oid))
    {
      mech = negotiate_GetMechByOID(&input_token.supportedMech);
      if (!mech)
        return SEC_E_INVALID_TOKEN;

      /* Make sure the specified mech is supported and get the appropriate credential */
      sub_cred = negotiate_FindCredential(creds, mech);
      if (!sub_cred)
        return SEC_E_INVALID_TOKEN;

      /* Clean up the optimistic mech */
      context->mech->pkg->table_w->DeleteSecurityContext(&context->sub_context);
      sub_context = nullptr;

      context->mech = mech;
      context->mic = TRUE;
    }

    /* Check neg_state (required on first response) */
    if (context->state < NEGOTIATE_STATE_NEGORESP)
    {
      switch (input_token.negState)
      {
        case NOSTATE:
          return SEC_E_INVALID_TOKEN;
        case REJECT:
          return SEC_E_LOGON_DENIED;
        case REQUEST_MIC:
          context->mic = TRUE;
          /* fallthrough */
          WINPR_FALLTHROUGH
        case ACCEPT_INCOMPLETE:
          context->state = NEGOTIATE_STATE_NEGORESP;
          break;
        case ACCEPT_COMPLETED:
          if (context->state == NEGOTIATE_STATE_INITIAL)
            context->state = NEGOTIATE_STATE_NEGORESP;
          else
            context->state = NEGOTIATE_STATE_FINAL;
          break;
        default:
          break;
      }

      WLog_DBG(TAG, "Negotiated mechanism: %s", negotiate_mech_name(context->mech->oid));
    }

    if (context->state == NEGOTIATE_STATE_NEGORESP)
    {
      /* Store the mech token in the output buffer */
      if (!output_buffer)
        goto cleanup;
      CopyMemory(&output_token.mechToken, output_buffer, sizeof(SecBuffer));

      mech_input_buffers[0] = input_token.mechToken;
      if (bindings_buffer)
        mech_input_buffers[1] = *bindings_buffer;

      status = context->mech->pkg->table_w->InitializeSecurityContextW(
          sub_cred, sub_context, pszTargetName, fContextReq | context->mech->flags, Reserved1,
          TargetDataRep, input_token.mechToken.cbBuffer ? &mech_input : nullptr, Reserved2,
          &context->sub_context, &mech_output, pfContextAttr, ptsExpiry);

      if (IsSecurityStatusError(status))
        return status;
    }

    if (status == SEC_E_OK)
    {
      if (output_token.mechToken.cbBuffer > 0)
        context->state = NEGOTIATE_STATE_MIC;
      else
        context->state = NEGOTIATE_STATE_FINAL;
    }

    /* Check if the acceptor sent its final token without a mic */
    if (context->state == NEGOTIATE_STATE_FINAL && input_token.mic.cbBuffer == 0)
    {
      if (context->mic || input_token.negState != ACCEPT_COMPLETED)
        return SEC_E_INVALID_TOKEN;

      if (output_buffer)
        output_buffer->cbBuffer = 0;
      return SEC_E_OK;
    }

    if ((context->state == NEGOTIATE_STATE_MIC && context->mic) ||
        context->state == NEGOTIATE_STATE_FINAL)
    {
      status = negotiate_mic_exchange(context, &input_token, &output_token, output_buffer);
      if (status != SEC_E_OK)
        return status;
    }
  }

  if (input_token.negState == ACCEPT_COMPLETED)
  {
    if (output_buffer)
      output_buffer->cbBuffer = 0;
    return SEC_E_OK;
  }

  if (output_token.negState == ACCEPT_COMPLETED)
    status = SEC_E_OK;
  else
    status = SEC_I_CONTINUE_NEEDED;

  if (!negotiate_write_neg_token(output_buffer, &output_token))
    status = SEC_E_INTERNAL_ERROR;

cleanup:
  WinPrAsn1Encoder_Free(&enc);
  return status;
}

static SECURITY_STATUS SEC_ENTRY negotiate_InitializeSecurityContextA(
    PCredHandle phCredential, PCtxtHandle phContext, SEC_CHAR* pszTargetName, ULONG fContextReq,
    ULONG Reserved1, ULONG TargetDataRep, PSecBufferDesc pInput, ULONG Reserved2,
    PCtxtHandle phNewContext, PSecBufferDesc pOutput, PULONG pfContextAttr, PTimeStamp ptsExpiry)
{
  SECURITY_STATUS status = 0;
  SEC_WCHAR* pszTargetNameW = nullptr;

  if (pszTargetName)
  {
    pszTargetNameW = ConvertUtf8ToWCharAlloc(pszTargetName, nullptr);
    if (!pszTargetNameW)
      return SEC_E_INTERNAL_ERROR;
  }

  status = negotiate_InitializeSecurityContextW(
      phCredential, phContext, pszTargetNameW, fContextReq, Reserved1, TargetDataRep, pInput,
      Reserved2, phNewContext, pOutput, pfContextAttr, ptsExpiry);
  free(pszTargetNameW);
  return status;
}

WINPR_ATTR_NODISCARD
static const Mech* guessMech(PSecBuffer input_buffer, BOOL* spNego, WinPrAsn1_OID* oid)
{
  WinPrAsn1Decoder decoder = WinPrAsn1Decoder_init();
  WinPrAsn1Decoder appDecoder = WinPrAsn1Decoder_init();
  WinPrAsn1_tagId tag = 0;
  const char ssp[] = "NTLMSSP";

  if (!input_buffer || !input_buffer->pvBuffer || (input_buffer->cbBuffer == 0))
    return nullptr;

  *spNego = FALSE;

  /* Check for NTLM token */
  if (input_buffer->cbBuffer >= 8 && strncmp(input_buffer->pvBuffer, ssp, sizeof(ssp)) == 0)
  {
    *oid = ntlm_OID;
    return negotiate_GetMechByOID(&ntlm_OID);
  }

  /* Read initialContextToken or raw Kerberos token */
  WinPrAsn1Decoder_InitMem(&decoder, WINPR_ASN1_DER, input_buffer->pvBuffer,
                           input_buffer->cbBuffer);

  if (!WinPrAsn1DecReadApp(&decoder, &tag, &appDecoder) || tag != 0)
    return nullptr;

  if (!WinPrAsn1DecReadOID(&appDecoder, oid, FALSE))
    return nullptr;

  if (sspi_gss_oid_compare(oid, &spnego_OID))
  {
    *spNego = TRUE;
    return nullptr;
  }

  return negotiate_GetMechByOID(oid);
}

static SECURITY_STATUS SEC_ENTRY negotiate_AcceptSecurityContext(
    PCredHandle phCredential, PCtxtHandle phContext, PSecBufferDesc pInput, ULONG fContextReq,
    ULONG TargetDataRep, PCtxtHandle phNewContext, PSecBufferDesc pOutput, PULONG pfContextAttr,
    PTimeStamp ptsTimeStamp)
{
  NEGOTIATE_CONTEXT* context = nullptr;
  NEGOTIATE_CONTEXT init_context = NEGOTIATE_CONTEXT_init();
  MechCred* creds = nullptr;
  PCredHandle sub_cred = nullptr;
  NegToken input_token = empty_neg_token;
  NegToken output_token = empty_neg_token;
  PSecBuffer input_buffer = nullptr;
  PSecBuffer output_buffer = nullptr;
  SecBufferDesc mech_input = { SECBUFFER_VERSION, 1, &input_token.mechToken };
  SecBufferDesc mech_output = { SECBUFFER_VERSION, 1, &output_token.mechToken };
  SECURITY_STATUS status = SEC_E_INTERNAL_ERROR;
  WinPrAsn1Decoder dec = WinPrAsn1Decoder_init();
  WinPrAsn1Decoder dec2 = WinPrAsn1Decoder_init();
  WinPrAsn1_tagId tag = 0;
  WinPrAsn1_OID oid = WINPR_C_ARRAY_INIT;
  const Mech* first_mech = nullptr;

  if (!phCredential || !SecIsValidHandle(phCredential))
    return SEC_E_NO_CREDENTIALS;

  creds = sspi_SecureHandleGetLowerPointer(phCredential);

  if (!pInput)
    return SEC_E_INVALID_TOKEN;

  /* behave like windows SSPIs that don't want empty context */
  if (phContext && !phContext->dwLower && !phContext->dwUpper)
    return SEC_E_INVALID_HANDLE;

  context = sspi_SecureHandleGetLowerPointer(phContext);

  input_buffer = sspi_FindSecBuffer(pInput, SECBUFFER_TOKEN);
  if (pOutput)
    output_buffer = sspi_FindSecBuffer(pOutput, SECBUFFER_TOKEN);

  if (!context)
  {
    init_context.mech = guessMech(input_buffer, &init_context.spnego, &oid);
    if (!init_context.mech && !init_context.spnego)
      return SEC_E_INVALID_TOKEN;

    WLog_DBG(TAG, "Mechanism: %s", negotiate_mech_name(&oid));

    if (init_context.spnego)
    {
      /* Process spnego token */
      if (!negotiate_read_neg_token(input_buffer, &input_token))
        return SEC_E_INVALID_TOKEN;

      /* First token must be negoTokenInit and must contain a mechList */
      if (!input_token.init || input_token.mechTypes.cbBuffer == 0)
        return SEC_E_INVALID_TOKEN;

      init_context.mechTypes.BufferType = SECBUFFER_DATA;
      init_context.mechTypes.cbBuffer = input_token.mechTypes.cbBuffer;

      /* Prepare to read mechList */
      WinPrAsn1Decoder_InitMem(&dec, WINPR_ASN1_DER, input_token.mechTypes.pvBuffer,
                               input_token.mechTypes.cbBuffer);

      if (!WinPrAsn1DecReadSequence(&dec, &dec2))
        return SEC_E_INVALID_TOKEN;
      dec = dec2;

      /* If an optimistic token was provided pass it into the first mech */
      if (input_token.mechToken.cbBuffer)
      {
        if (!WinPrAsn1DecReadOID(&dec, &oid, FALSE))
          return SEC_E_INVALID_TOKEN;

        init_context.mech = negotiate_GetMechByOID(&oid);

        if (init_context.mech)
        {
          if (output_buffer)
            output_token.mechToken = *output_buffer;
          WLog_DBG(TAG, "Requested mechanism: %s",
                   negotiate_mech_name(init_context.mech->oid));
        }
      }
    }

    if (init_context.mech)
    {
      sub_cred = negotiate_FindCredential(creds, init_context.mech);

      if (sub_cred)
      {
        status = init_context.mech->pkg->table->AcceptSecurityContext(
            sub_cred, nullptr, init_context.spnego ? &mech_input : pInput, fContextReq,
            TargetDataRep, &init_context.sub_context,
            init_context.spnego ? &mech_output : pOutput, pfContextAttr, ptsTimeStamp);
      }
    }

    if (IsSecurityStatusError(status))
    {
      if (!init_context.spnego)
        return status;

      /* Clean up any partially created sub context before falling back to
       * another mechanism (mirrors the mech change handling in
       * negotiate_InitializeSecurityContextW) */
      if (init_context.mech)
        init_context.mech->pkg->table->DeleteSecurityContext(&init_context.sub_context);

      init_context.mic = TRUE;
      first_mech = init_context.mech;
      init_context.mech = nullptr;
      output_token.mechToken.cbBuffer = 0;
    }

    while (!init_context.mech && WinPrAsn1DecPeekTag(&dec, &tag))
    {
      /* Read each mechanism */
      if (!WinPrAsn1DecReadOID(&dec, &oid, FALSE))
        return SEC_E_INVALID_TOKEN;

      init_context.mech = negotiate_GetMechByOID(&oid);
      WLog_DBG(TAG, "Requested mechanism: %s", negotiate_mech_name(&oid));

      /* Microsoft may send two versions of the kerberos OID */
      if (init_context.mech == first_mech)
        init_context.mech = nullptr;

      if (init_context.mech && !negotiate_FindCredential(creds, init_context.mech))
        init_context.mech = nullptr;
    }

    if (!init_context.mech)
      return SEC_E_INTERNAL_ERROR;

    context = negotiate_ContextNew(&init_context);
    if (!context)
    {
      if (!IsSecurityStatusError(status))
        init_context.mech->pkg->table->DeleteSecurityContext(&init_context.sub_context);
      return SEC_E_INSUFFICIENT_MEMORY;
    }

    sspi_SecureHandleSetPackageId(phNewContext, SSPI_PACKAGE_NEGOTIATE);
    sspi_SecureHandleSetLowerPointer(phNewContext, context);

    if (!init_context.spnego)
      return status;

    CopyMemory(init_context.mechTypes.pvBuffer, input_token.mechTypes.pvBuffer,
               input_token.mechTypes.cbBuffer);

    if (!context->mech->preferred)
    {
      output_token.negState = REQUEST_MIC;
      context->mic = TRUE;
    }
    else
    {
      output_token.negState = ACCEPT_INCOMPLETE;
    }

    if (status == SEC_E_OK)
      context->state = NEGOTIATE_STATE_FINAL;
    else
      context->state = NEGOTIATE_STATE_NEGORESP;

    output_token.supportedMech = oid;
    WLog_DBG(TAG, "Accepted mechanism: %s", negotiate_mech_name(&output_token.supportedMech));
  }
  else
  {
    sub_cred = negotiate_FindCredential(creds, context->mech);
    if (!sub_cred)
      return SEC_E_NO_CREDENTIALS;

    if (!context->spnego)
    {
      return context->mech->pkg->table->AcceptSecurityContext(
          sub_cred, &context->sub_context, pInput, fContextReq, TargetDataRep,
          &context->sub_context, pOutput, pfContextAttr, ptsTimeStamp);
    }

    if (!negotiate_read_neg_token(input_buffer, &input_token))
      return SEC_E_INVALID_TOKEN;

    /* Process the mechanism token */
    if (input_token.mechToken.cbBuffer > 0)
    {
      if (context->state != NEGOTIATE_STATE_NEGORESP)
        return SEC_E_INVALID_TOKEN;

      /* Use the output buffer to store the optimistic token */
      if (output_buffer)
        CopyMemory(&output_token.mechToken, output_buffer, sizeof(SecBuffer));

      /* If the client's optimistic mechanism was not accepted the sub
       * context was never created (or was cleaned up); pass NULL so the
       * selected mechanism creates a fresh context instead of rejecting
       * the empty handle with SEC_E_INVALID_HANDLE */
      PCtxtHandle sub_context = sspi_SecureHandleGetLowerPointer(&context->sub_context)
                                    ? &context->sub_context
                                    : nullptr;
      status = context->mech->pkg->table->AcceptSecurityContext(
          sub_cred, sub_context, &mech_input, fContextReq | context->mech->flags,
          TargetDataRep, &context->sub_context, &mech_output, pfContextAttr, ptsTimeStamp);

      if (IsSecurityStatusError(status))
        return status;

      if (status == SEC_E_OK)
        context->state = NEGOTIATE_STATE_FINAL;
    }
    else if (context->state == NEGOTIATE_STATE_NEGORESP)
      return SEC_E_INVALID_TOKEN;
  }

  if (context->state == NEGOTIATE_STATE_FINAL)
  {
    /* Check if initiator sent the last mech token without a mic and a mic was required */
    if (context->mic && output_token.mechToken.cbBuffer == 0 && input_token.mic.cbBuffer == 0)
      return SEC_E_INVALID_TOKEN;

    if (context->mic || input_token.mic.cbBuffer > 0)
    {
      status = negotiate_mic_exchange(context, &input_token, &output_token, output_buffer);
      if (status != SEC_E_OK)
        return status;
    }
    else
      output_token.negState = ACCEPT_COMPLETED;
  }

  if (input_token.negState == ACCEPT_COMPLETED)
  {
    if (output_buffer)
      output_buffer->cbBuffer = 0;
    return SEC_E_OK;
  }

  if (output_token.negState == ACCEPT_COMPLETED)
    status = SEC_E_OK;
  else
    status = SEC_I_CONTINUE_NEEDED;

  if (!negotiate_write_neg_token(output_buffer, &output_token))
    return SEC_E_INTERNAL_ERROR;

  return status;
}

static SECURITY_STATUS SEC_ENTRY negotiate_CompleteAuthToken(PCtxtHandle phContext,
                                                             PSecBufferDesc pToken)
{
  NEGOTIATE_CONTEXT* context = nullptr;
  SECURITY_STATUS status = SEC_E_OK;
  context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  if (context->mech->pkg->table->CompleteAuthToken)
    status = context->mech->pkg->table->CompleteAuthToken(&context->sub_context, pToken);

  return status;
}

static SECURITY_STATUS SEC_ENTRY negotiate_DeleteSecurityContext(PCtxtHandle phContext)
{
  SECURITY_STATUS status = SEC_E_OK;
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
  sspi_SecureHandleInvalidate(phContext);
  const SecPkg* pkg = nullptr;

  if (!context)
    return SEC_E_INVALID_HANDLE;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  pkg = context->mech->pkg;

  if (pkg->table->DeleteSecurityContext)
    status = pkg->table->DeleteSecurityContext(&context->sub_context);

  negotiate_ContextFree(context);
  return status;
}

static SECURITY_STATUS SEC_ENTRY
negotiate_ImpersonateSecurityContext(WINPR_ATTR_UNUSED PCtxtHandle phContext)
{
  return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY
negotiate_RevertSecurityContext(WINPR_ATTR_UNUSED PCtxtHandle phContext)
{
  return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY negotiate_QueryContextAttributesW(PCtxtHandle phContext,
                                                                   ULONG ulAttribute, void* pBuffer)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table_w);
  if (context->mech->pkg->table_w->QueryContextAttributesW)
    return context->mech->pkg->table_w->QueryContextAttributesW(&context->sub_context,
                                                                ulAttribute, pBuffer);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_QueryContextAttributesA(PCtxtHandle phContext,
                                                                   ULONG ulAttribute, void* pBuffer)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  if (context->mech->pkg->table->QueryContextAttributesA)
    return context->mech->pkg->table->QueryContextAttributesA(&context->sub_context,
                                                              ulAttribute, pBuffer);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_SetContextAttributesW(PCtxtHandle phContext,
                                                                 ULONG ulAttribute, void* pBuffer,
                                                                 ULONG cbBuffer)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table_w);
  if (context->mech->pkg->table_w->SetContextAttributesW)
    return context->mech->pkg->table_w->SetContextAttributesW(&context->sub_context,
                                                              ulAttribute, pBuffer, cbBuffer);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_SetContextAttributesA(PCtxtHandle phContext,
                                                                 ULONG ulAttribute, void* pBuffer,
                                                                 ULONG cbBuffer)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  if (context->mech->pkg->table->SetContextAttributesA)
    return context->mech->pkg->table->SetContextAttributesA(&context->sub_context, ulAttribute,
                                                            pBuffer, cbBuffer);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_SetCredentialsAttributesW(PCredHandle phCredential,
                                                                     ULONG ulAttribute,
                                                                     void* pBuffer, ULONG cbBuffer)
{
  BOOL success = FALSE;
  MechCred* creds = sspi_SecureHandleGetLowerPointer(phCredential);

  if (!creds)
    return SEC_E_INVALID_HANDLE;

  for (size_t i = 0; i < MECH_COUNT; i++)
  {
    MechCred* cred = &creds[i];

    WINPR_ASSERT(cred->mech);
    WINPR_ASSERT(cred->mech->pkg);
    WINPR_ASSERT(cred->mech->pkg->table);
    WINPR_ASSERT(cred->mech->pkg->table_w->SetCredentialsAttributesW);
    const SECURITY_STATUS secStatus = cred->mech->pkg->table_w->SetCredentialsAttributesW(
        &cred->cred, ulAttribute, pBuffer, cbBuffer);

    if (secStatus == SEC_E_OK)
      success = TRUE;
    else
      WLog_WARN(TAG, "SetCredentialsAttributesW returned %s",
                GetSecurityStatusString(secStatus));
  }

  // return success if at least one submodule accepts the credential attribute
  return (success ? SEC_E_OK : SEC_E_UNSUPPORTED_FUNCTION);
}

static SECURITY_STATUS SEC_ENTRY negotiate_SetCredentialsAttributesA(PCredHandle phCredential,
                                                                     ULONG ulAttribute,
                                                                     void* pBuffer, ULONG cbBuffer)
{
  BOOL success = FALSE;

  MechCred* creds = sspi_SecureHandleGetLowerPointer(phCredential);

  if (!creds)
    return SEC_E_INVALID_HANDLE;

  for (size_t i = 0; i < MECH_COUNT; i++)
  {
    MechCred* cred = &creds[i];

    if (!cred->valid)
      continue;

    WINPR_ASSERT(cred->mech);
    WINPR_ASSERT(cred->mech->pkg);
    WINPR_ASSERT(cred->mech->pkg->table);
    WINPR_ASSERT(cred->mech->pkg->table->SetCredentialsAttributesA);
    const SECURITY_STATUS secStatus = cred->mech->pkg->table->SetCredentialsAttributesA(
        &cred->cred, ulAttribute, pBuffer, cbBuffer);

    if (secStatus == SEC_E_OK)
    {
      success = TRUE;
    }
    else
      WLog_WARN(TAG, "SetCredentialsAttributesA returned %s",
                GetSecurityStatusString(secStatus));
  }

  // return success if at least one submodule accepts the credential attribute
  return (success ? SEC_E_OK : SEC_E_UNSUPPORTED_FUNCTION);
}

WINPR_ATTR_NODISCARD
static BOOL checkMechCredValid(void* pAuthData, MechCred* cred)
{
  WINPR_ASSERT(cred);
  WINPR_ASSERT(cred->mech);
  WINPR_ASSERT(cred->mech->pkg);

  BOOL kerberos = FALSE;
  BOOL ntlm = FALSE;
  BOOL u2u = FALSE;
  if (!negotiate_get_config(pAuthData, &kerberos, &ntlm, &u2u))
  {
    WLog_DBG(TAG, "Failed to get negotiate configuration");
    return FALSE;
  }

  if (!kerberos && sspi_gss_oid_compare(cred->mech->oid, &kerberos_OID))
  {
    WLog_DBG(TAG, "Kerberos disabled, skipping");
    return FALSE;
  }

  if (!u2u && sspi_gss_oid_compare(cred->mech->oid, &kerberos_u2u_OID))
  {
    WLog_DBG(TAG, "Kerberos U2U disabled, skipping");
    return FALSE;
  }

  if (!ntlm && _tcsncmp(cred->mech->pkg->name, NTLM_SSP_NAME, ARRAYSIZE(NTLM_SSP_NAME)) == 0)
  {
    WLog_DBG(TAG, "NTLM disabled, skipping");
    return FALSE;
  }
  return TRUE;
}

static SECURITY_STATUS SEC_ENTRY negotiate_AcquireCredentialsHandleW(
    SEC_WCHAR* pszPrincipal, SEC_WCHAR* pszPackage, ULONG fCredentialUse, void* pvLogonID,
    void* pAuthData, SEC_GET_KEY_FN pGetKeyFn, void* pvGetKeyArgument, PCredHandle phCredential,
    PTimeStamp ptsExpiry)
{
  MechCred* creds = calloc(MECH_COUNT, sizeof(MechCred));

  if (!creds)
    return SEC_E_INTERNAL_ERROR;

  for (size_t i = 0; i < MECH_COUNT; i++)
  {
    MechCred* cred = &creds[i];
    const SecPkg* pkg = MechTable[i].pkg;
    cred->mech = &MechTable[i];

    if (!checkMechCredValid(pAuthData, cred))
      continue;

    WINPR_ASSERT(pkg->table_w);
    WINPR_ASSERT(pkg->table_w->AcquireCredentialsHandleW);
    const SECURITY_STATUS rc = pkg->table_w->AcquireCredentialsHandleW(
        pszPrincipal, pszPackage, fCredentialUse, pvLogonID, pAuthData, pGetKeyFn,
        pvGetKeyArgument, &cred->cred, ptsExpiry);
    if (rc != SEC_E_OK)
    {
      WLog_DBG(TAG, "AcquireCredentialsHandleW returned %s", GetSecurityStatusString(rc));
      continue;
    }

    cred->valid = TRUE;
  }

  sspi_SecureHandleSetLowerPointer(phCredential, (void*)creds);
  sspi_SecureHandleSetPackageId(phCredential, SSPI_PACKAGE_NEGOTIATE);
  return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY negotiate_AcquireCredentialsHandleA(
    SEC_CHAR* pszPrincipal, SEC_CHAR* pszPackage, ULONG fCredentialUse, void* pvLogonID,
    void* pAuthData, SEC_GET_KEY_FN pGetKeyFn, void* pvGetKeyArgument, PCredHandle phCredential,
    PTimeStamp ptsExpiry)
{
  MechCred* creds = calloc(MECH_COUNT, sizeof(MechCred));

  if (!creds)
    return SEC_E_INTERNAL_ERROR;

  for (size_t i = 0; i < MECH_COUNT; i++)
  {
    const SecPkg* pkg = MechTable[i].pkg;
    MechCred* cred = &creds[i];

    cred->mech = &MechTable[i];

    if (!checkMechCredValid(pAuthData, cred))
      continue;

    WINPR_ASSERT(pkg->table);
    WINPR_ASSERT(pkg->table->AcquireCredentialsHandleA);
    const SECURITY_STATUS rc = pkg->table->AcquireCredentialsHandleA(
        pszPrincipal, pszPackage, fCredentialUse, pvLogonID, pAuthData, pGetKeyFn,
        pvGetKeyArgument, &cred->cred, ptsExpiry);
    if (rc != SEC_E_OK)
    {
      WLog_DBG(TAG, "AcquireCredentialsHandleA returned %s", GetSecurityStatusString(rc));
      continue;
    }

    cred->valid = TRUE;
  }

  sspi_SecureHandleSetLowerPointer(phCredential, (void*)creds);
  sspi_SecureHandleSetPackageId(phCredential, SSPI_PACKAGE_NEGOTIATE);
  return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY negotiate_QueryCredentialsAttributesW(
    WINPR_ATTR_UNUSED PCredHandle phCredential, WINPR_ATTR_UNUSED ULONG ulAttribute,
    WINPR_ATTR_UNUSED void* pBuffer)
{
  WLog_ERR(TAG, "TODO: Implement");
  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_QueryCredentialsAttributesA(
    WINPR_ATTR_UNUSED PCredHandle phCredential, WINPR_ATTR_UNUSED ULONG ulAttribute,
    WINPR_ATTR_UNUSED void* pBuffer)
{
  WLog_ERR(TAG, "TODO: Implement");
  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_FreeCredentialsHandle(PCredHandle phCredential)
{
  MechCred* creds = sspi_SecureHandleGetLowerPointer(phCredential);
  sspi_SecureHandleInvalidate(phCredential);
  if (!creds)
    return SEC_E_INVALID_HANDLE;

  for (size_t i = 0; i < MECH_COUNT; i++)
  {
    MechCred* cred = &creds[i];

    WINPR_ASSERT(cred->mech);
    WINPR_ASSERT(cred->mech->pkg);
    WINPR_ASSERT(cred->mech->pkg->table);
    WINPR_ASSERT(cred->mech->pkg->table->FreeCredentialsHandle);
    const SECURITY_STATUS rc = cred->mech->pkg->table->FreeCredentialsHandle(&cred->cred);
    if (rc != SEC_E_OK)
      WLog_DBG(TAG, "FreeCredentialsHandle returned %s", GetSecurityStatusString(rc));
  }
  free(creds);

  return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY negotiate_EncryptMessage(PCtxtHandle phContext, ULONG fQOP,
                                                          PSecBufferDesc pMessage,
                                                          ULONG MessageSeqNo)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  if (context->mic)
    MessageSeqNo++;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  if (context->mech->pkg->table->EncryptMessage)
    return context->mech->pkg->table->EncryptMessage(&context->sub_context, fQOP, pMessage,
                                                     MessageSeqNo);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_DecryptMessage(PCtxtHandle phContext,
                                                          PSecBufferDesc pMessage,
                                                          ULONG MessageSeqNo, ULONG* pfQOP)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  if (context->mic)
    MessageSeqNo++;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  if (context->mech->pkg->table->DecryptMessage)
    return context->mech->pkg->table->DecryptMessage(&context->sub_context, pMessage,
                                                     MessageSeqNo, pfQOP);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_MakeSignature(PCtxtHandle phContext, ULONG fQOP,
                                                         PSecBufferDesc pMessage,
                                                         ULONG MessageSeqNo)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  if (context->mic)
    MessageSeqNo++;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  if (context->mech->pkg->table->MakeSignature)
    return context->mech->pkg->table->MakeSignature(&context->sub_context, fQOP, pMessage,
                                                    MessageSeqNo);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY negotiate_VerifySignature(PCtxtHandle phContext,
                                                           PSecBufferDesc pMessage,
                                                           ULONG MessageSeqNo, ULONG* pfQOP)
{
  NEGOTIATE_CONTEXT* context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

  if (!context)
    return SEC_E_INVALID_HANDLE;

  if (context->mic)
    MessageSeqNo++;

  WINPR_ASSERT(context->mech);
  WINPR_ASSERT(context->mech->pkg);
  WINPR_ASSERT(context->mech->pkg->table);
  if (context->mech->pkg->table->VerifySignature)
    return context->mech->pkg->table->VerifySignature(&context->sub_context, pMessage,
                                                      MessageSeqNo, pfQOP);

  return SEC_E_UNSUPPORTED_FUNCTION;
}

const SecurityFunctionTableA NEGOTIATE_SecurityFunctionTableA = {
  3,                                     /* dwVersion */
  nullptr,                               /* EnumerateSecurityPackages */
  negotiate_QueryCredentialsAttributesA, /* QueryCredentialsAttributes */
  negotiate_AcquireCredentialsHandleA,   /* AcquireCredentialsHandle */
  negotiate_FreeCredentialsHandle,       /* FreeCredentialsHandle */
  nullptr,                               /* Reserved2 */
  negotiate_InitializeSecurityContextA,  /* InitializeSecurityContext */
  negotiate_AcceptSecurityContext,       /* AcceptSecurityContext */
  negotiate_CompleteAuthToken,           /* CompleteAuthToken */
  negotiate_DeleteSecurityContext,       /* DeleteSecurityContext */
  nullptr,                               /* ApplyControlToken */
  negotiate_QueryContextAttributesA,     /* QueryContextAttributes */
  negotiate_ImpersonateSecurityContext,  /* ImpersonateSecurityContext */
  negotiate_RevertSecurityContext,       /* RevertSecurityContext */
  negotiate_MakeSignature,               /* MakeSignature */
  negotiate_VerifySignature,             /* VerifySignature */
  nullptr,                               /* FreeContextBuffer */
  nullptr,                               /* QuerySecurityPackageInfo */
  nullptr,                               /* Reserved3 */
  nullptr,                               /* Reserved4 */
  nullptr,                               /* ExportSecurityContext */
  nullptr,                               /* ImportSecurityContext */
  nullptr,                               /* AddCredentials */
  nullptr,                               /* Reserved8 */
  nullptr,                               /* QuerySecurityContextToken */
  negotiate_EncryptMessage,              /* EncryptMessage */
  negotiate_DecryptMessage,              /* DecryptMessage */
  negotiate_SetContextAttributesA,       /* SetContextAttributes */
  negotiate_SetCredentialsAttributesA,   /* SetCredentialsAttributes */
};

const SecurityFunctionTableW NEGOTIATE_SecurityFunctionTableW = {
  3,                                     /* dwVersion */
  nullptr,                               /* EnumerateSecurityPackages */
  negotiate_QueryCredentialsAttributesW, /* QueryCredentialsAttributes */
  negotiate_AcquireCredentialsHandleW,   /* AcquireCredentialsHandle */
  negotiate_FreeCredentialsHandle,       /* FreeCredentialsHandle */
  nullptr,                               /* Reserved2 */
  negotiate_InitializeSecurityContextW,  /* InitializeSecurityContext */
  negotiate_AcceptSecurityContext,       /* AcceptSecurityContext */
  negotiate_CompleteAuthToken,           /* CompleteAuthToken */
  negotiate_DeleteSecurityContext,       /* DeleteSecurityContext */
  nullptr,                               /* ApplyControlToken */
  negotiate_QueryContextAttributesW,     /* QueryContextAttributes */
  negotiate_ImpersonateSecurityContext,  /* ImpersonateSecurityContext */
  negotiate_RevertSecurityContext,       /* RevertSecurityContext */
  negotiate_MakeSignature,               /* MakeSignature */
  negotiate_VerifySignature,             /* VerifySignature */
  nullptr,                               /* FreeContextBuffer */
  nullptr,                               /* QuerySecurityPackageInfo */
  nullptr,                               /* Reserved3 */
  nullptr,                               /* Reserved4 */
  nullptr,                               /* ExportSecurityContext */
  nullptr,                               /* ImportSecurityContext */
  nullptr,                               /* AddCredentials */
  nullptr,                               /* Reserved8 */
  nullptr,                               /* QuerySecurityContextToken */
  negotiate_EncryptMessage,              /* EncryptMessage */
  negotiate_DecryptMessage,              /* DecryptMessage */
  negotiate_SetContextAttributesW,       /* SetContextAttributes */
  negotiate_SetCredentialsAttributesW,   /* SetCredentialsAttributes */
};

BOOL NEGOTIATE_init(void)
{
  InitializeConstWCharFromUtf8(NEGOTIATE_SecPkgInfoA.Name, NEGOTIATE_SecPkgInfoW_NameBuffer,
                               ARRAYSIZE(NEGOTIATE_SecPkgInfoW_NameBuffer));
  InitializeConstWCharFromUtf8(NEGOTIATE_SecPkgInfoA.Comment, NEGOTIATE_SecPkgInfoW_CommentBuffer,
                               ARRAYSIZE(NEGOTIATE_SecPkgInfoW_CommentBuffer));

  return TRUE;
}

Coverage Report

Created: 2026-10-28 06:49