/***************************************************************************

 *                                  _   _ ____  _

 *  Project                     ___| | | |  _ \| |

 *                             / __| | | | |_) | |

 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.

 *

 * This software is licensed as described in the file COPYING, which

 * you should have received as part of this distribution. The terms

 * are also available at https://curl.se/docs/copyright.html.

 *

 * You may opt to use, copy, modify, merge, publish, distribute and/or sell

 * copies of the Software, and permit persons to whom the Software is

 * furnished to do so, under the terms of the COPYING file.

 *

 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY

 * KIND, either express or implied.

 *

 * SPDX-License-Identifier: curl

 *

 ***************************************************************************/

#include "curl_setup.h"

#if !defined(CURL_DISABLE_HTTP) && defined(USE_NTLM)

/*

 * NTLM details:

 *

 * https://davenport.sourceforge.net/ntlm.html

 * https://www.innovation.ch/java/ntlm.html

 */

#include "urldata.h"

#include "curl_trc.h"

#include "strcase.h"

#include "http_ntlm.h"

#include "curl_ntlm_core.h"

#include "curlx/base64.h"

#include "vauth/vauth.h"

#include "url.h"

#include "curlx/strparse.h"

/* SSL backend-specific #if branches in this file must be kept in the order

   documented in curl_ntlm_core. */

#ifdef USE_WINDOWS_SSPI

#include "curl_sspi.h"

#endif

CURLcode Curl_input_ntlm(struct Curl_easy *data,

                         bool proxy,         /* if proxy or not */

                         const char *header) /* rest of the www-authenticate:

                                                header */

{

  /* point to the correct struct with this */

  curlntlm *state;

  CURLcode result = CURLE_OK;

  struct connectdata *conn = data->conn;

  state = proxy ? &conn->proxy_ntlm_state : &conn->http_ntlm_state;

  if(checkprefix("NTLM", header)) {

    struct ntlmdata *ntlm = Curl_auth_ntlm_get(conn, proxy);

    if(!ntlm)

      return CURLE_OUT_OF_MEMORY;

    header += strlen("NTLM");

    curlx_str_passblanks(&header);

    if(*header) {

      unsigned char *hdr;

      size_t hdrlen;

      result = curlx_base64_decode(header, &hdr, &hdrlen);

      if(!result) {

        struct bufref hdrbuf;

        Curl_bufref_init(&hdrbuf);

        Curl_bufref_set(&hdrbuf, hdr, hdrlen, curl_free);

        result = Curl_auth_decode_ntlm_type2_message(data, &hdrbuf, ntlm);

        Curl_bufref_free(&hdrbuf);

      }

      if(result)

        return result;

      *state = NTLMSTATE_TYPE2; /* We got a type-2 message */

    }

    else {

      if(*state == NTLMSTATE_LAST) {

        infof(data, "NTLM auth restarted");

        Curl_auth_ntlm_remove(conn, proxy);

      }

      else if(*state == NTLMSTATE_TYPE3) {

        infof(data, "NTLM handshake rejected");

        Curl_auth_ntlm_remove(conn, proxy);

        *state = NTLMSTATE_NONE;

        return CURLE_REMOTE_ACCESS_DENIED;

      }

      else if(*state >= NTLMSTATE_TYPE1) {

        infof(data, "NTLM handshake failure (internal error)");

        return CURLE_REMOTE_ACCESS_DENIED;

      }

      *state = NTLMSTATE_TYPE1; /* We should send away a type-1 */

    }

  }

  return result;

}

/*

 * This is for creating NTLM header output

 */

CURLcode Curl_output_ntlm(struct Curl_easy *data, bool proxy)

{

  char *base64 = NULL;

  size_t len = 0;

  CURLcode result = CURLE_OK;

  struct bufref ntlmmsg;

  /* point to the address of the pointer that holds the string to send to the

     server, which is for a plain host or for an HTTP proxy */

  char **allocuserpwd;

  /* point to the username, password, service and host */

  const char *userp;

  const char *passwdp;

  const char *service = NULL;

  const char *hostname = NULL;

  /* point to the correct struct with this */

  struct ntlmdata *ntlm;

  curlntlm *state;

  struct auth *authp;

  struct connectdata *conn = data->conn;

  DEBUGASSERT(conn);

  DEBUGASSERT(data);

  if(proxy) {

#ifndef CURL_DISABLE_PROXY

    allocuserpwd = &data->state.aptr.proxyuserpwd;

    userp = data->state.aptr.proxyuser;

    passwdp = data->state.aptr.proxypasswd;

    service = data->set.str[STRING_PROXY_SERVICE_NAME] ?

              data->set.str[STRING_PROXY_SERVICE_NAME] : "HTTP";

    hostname = conn->http_proxy.host.name;

    state = &conn->proxy_ntlm_state;

    authp = &data->state.authproxy;

#else

    return CURLE_NOT_BUILT_IN;

#endif

  }

  else {

    allocuserpwd = &data->state.aptr.userpwd;

    userp = data->state.aptr.user;

    passwdp = data->state.aptr.passwd;

    service = data->set.str[STRING_SERVICE_NAME] ?

              data->set.str[STRING_SERVICE_NAME] : "HTTP";

    hostname = conn->host.name;

    state = &conn->http_ntlm_state;

    authp = &data->state.authhost;

  }

  ntlm = Curl_auth_ntlm_get(conn, proxy);

  if(!ntlm)

    return CURLE_OUT_OF_MEMORY;

  authp->done = FALSE;

  /* not set means empty */

  if(!userp)

    userp = "";

  if(!passwdp)

    passwdp = "";

#ifdef USE_WINDOWS_SSPI

  if(!Curl_pSecFn) {

    /* not thread-safe and leaks - use curl_global_init() to avoid */

    CURLcode err = Curl_sspi_global_init();

    if(!Curl_pSecFn)

      return err;

  }

#ifdef SECPKG_ATTR_ENDPOINT_BINDINGS

  ntlm->sslContext = conn->sslContext;

#endif

#endif

  Curl_bufref_init(&ntlmmsg);

  /* connection is already authenticated, do not send a header in future

   * requests so go directly to NTLMSTATE_LAST */

  if(*state == NTLMSTATE_TYPE3)

    *state = NTLMSTATE_LAST;

  switch(*state) {

  case NTLMSTATE_TYPE1:

  default: /* for the weird cases we (re)start here */

    /* Create a type-1 message */

    result = Curl_auth_create_ntlm_type1_message(data, userp, passwdp, service,

                                                 hostname, ntlm, &ntlmmsg);

    if(!result) {

      DEBUGASSERT(Curl_bufref_len(&ntlmmsg) != 0);

      result = curlx_base64_encode(Curl_bufref_uptr(&ntlmmsg),

                                   Curl_bufref_len(&ntlmmsg), &base64, &len);

      if(!result) {

        curlx_free(*allocuserpwd);

        *allocuserpwd = curl_maprintf("%sAuthorization: NTLM %s\r\n",

                                      proxy ? "Proxy-" : "", base64);

        curlx_free(base64);

        if(!*allocuserpwd)

          result = CURLE_OUT_OF_MEMORY;

      }

    }

    break;

  case NTLMSTATE_TYPE2:

    /* We already received the type-2 message, create a type-3 message */

    result = Curl_auth_create_ntlm_type3_message(data, userp, passwdp,

                                                 ntlm, &ntlmmsg);

    if(!result && Curl_bufref_len(&ntlmmsg)) {

      result = curlx_base64_encode(Curl_bufref_uptr(&ntlmmsg),

                                   Curl_bufref_len(&ntlmmsg), &base64, &len);

      if(!result) {

        curlx_free(*allocuserpwd);

        *allocuserpwd = curl_maprintf("%sAuthorization: NTLM %s\r\n",

                                      proxy ? "Proxy-" : "", base64);

        curlx_free(base64);

        if(!*allocuserpwd)

          result = CURLE_OUT_OF_MEMORY;

        else {

          *state = NTLMSTATE_TYPE3; /* we send a type-3 */

          authp->done = TRUE;

        }

      }

    }

    break;

  case NTLMSTATE_LAST:

    /* since this is a little artificial in that this is used without any

       outgoing auth headers being set, we need to set the bit by force */

    if(proxy)

      data->info.proxyauthpicked = CURLAUTH_NTLM;

    else

      data->info.httpauthpicked = CURLAUTH_NTLM;

    Curl_safefree(*allocuserpwd);

    authp->done = TRUE;

    break;

  }

  Curl_bufref_free(&ntlmmsg);

  return result;

}

#endif /* !CURL_DISABLE_HTTP && USE_NTLM */