text: /***************************************************************************
   *                                  _   _ ____  _
   *  Project                     ___| | | |  _ \| |
   *                             / __| | | | |_) | |
   *                            | (__| |_| |  _ <| |___
   *                             \___|\___/|_| \_\_____|
   *
   * Copyright (C) 1998 - 2021, 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.
   *
   * RFC4616 PLAIN authentication
   * Draft   LOGIN SASL Mechanism <draft-murchison-sasl-login-00.txt>
   *
   ***************************************************************************/
  
  #include "curl_setup.h"
  
  #if !defined(CURL_DISABLE_IMAP) || !defined(CURL_DISABLE_SMTP) ||       \
    !defined(CURL_DISABLE_POP3)
  
  #include <curl/curl.h>
  #include "urldata.h"
  
  #include "vauth/vauth.h"
  #include "curl_md5.h"
  #include "warnless.h"
  #include "strtok.h"
  #include "sendf.h"
  #include "curl_printf.h"
  
  /* The last #include files should be: */
  #include "curl_memory.h"
  #include "memdebug.h"
  
  /*
   * Curl_auth_create_plain_message()
   *
   * This is used to generate an already encoded PLAIN message ready
   * for sending to the recipient.
   *
   * Parameters:
   *
   * authzid [in]     - The authorization identity.
   * authcid [in]     - The authentication identity.
   * passwd  [in]     - The password.
   * out     [out]    - The result storage.
   *
   * Returns CURLE_OK on success.
   */
  CURLcode Curl_auth_create_plain_message(const char *authzid,
                                          const char *authcid,
                                          const char *passwd,
                                          struct bufref *out)
  {
    char *plainauth;
    size_t plainlen;
    size_t zlen;
    size_t clen;
    size_t plen;
  
    zlen = (authzid == NULL ? 0 : strlen(authzid));
    clen = strlen(authcid);
    plen = strlen(passwd);
  
    /* Compute binary message length. Check for overflows. */
    if((zlen > SIZE_T_MAX/4) || (clen > SIZE_T_MAX/4) ||
       (plen > (SIZE_T_MAX/2 - 2)))
      return CURLE_OUT_OF_MEMORY;
    plainlen = zlen + clen + plen + 2;
  
    plainauth = malloc(plainlen + 1);
    if(!plainauth)
      return CURLE_OUT_OF_MEMORY;
  
    /* Calculate the reply */
    if(zlen)
      memcpy(plainauth, authzid, zlen);
    plainauth[zlen] = '\0';
    memcpy(plainauth + zlen + 1, authcid, clen);
    plainauth[zlen + clen + 1] = '\0';
    memcpy(plainauth + zlen + clen + 2, passwd, plen);
    plainauth[plainlen] = '\0';
    Curl_bufref_set(out, plainauth, plainlen, curl_free);
    return CURLE_OK;
  }
  
  /*
   * Curl_auth_create_login_message()
   *
   * This is used to generate an already encoded LOGIN message containing the
   * user name or password ready for sending to the recipient.
   *
   * Parameters:
   *
   * valuep  [in]     - The user name or user's password.
   * out     [out]    - The result storage.
   *
   * Returns CURLE_OK on success.
   */
  CURLcode Curl_auth_create_login_message(const char *valuep, struct bufref *out)
  {
    Curl_bufref_set(out, valuep, strlen(valuep), NULL);
    return CURLE_OK;
  }
  
  /*
   * Curl_auth_create_external_message()
   *
   * This is used to generate an already encoded EXTERNAL message containing
   * the user name ready for sending to the recipient.
   *
   * Parameters:
   *
   * user    [in]     - The user name.
   * out     [out]    - The result storage.
   *
   * Returns CURLE_OK on success.
   */
  CURLcode Curl_auth_create_external_message(const char *user,
                                             struct bufref *out)
  {
    /* This is the same formatting as the login message */
    return Curl_auth_create_login_message(user, out);
  }
  
  #endif /* if no users */
  