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

 *                                  _   _ ____  _

 *  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(USE_NTLM) && !defined(USE_WINDOWS_SSPI)

/*

 * NTLM details:

 *

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

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

 */

#define DEBUG_ME 0

#include "vauth.h"

#include "../sendf.h"

#include "../curl_ntlm_core.h"

#include "../curl_gethostname.h"

#include "../curlx/warnless.h"

#include "../rand.h"

#include "../vtls/vtls.h"

#include "../strdup.h"

#include "../curl_endian.h"

/* NTLM buffer fixed size, large enough for long user + host + domain */

#define NTLM_BUFSIZE 1024

/* Flag bits definitions based on

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

#define NTLMFLAG_NEGOTIATE_UNICODE               (1<<0)

/* Indicates that Unicode strings are supported for use in security buffer

   data. */

#define NTLMFLAG_NEGOTIATE_OEM                   (1<<1)

/* Indicates that OEM strings are supported for use in security buffer data. */

#define NTLMFLAG_REQUEST_TARGET                  (1<<2)

/* Requests that the server's authentication realm be included in the Type 2

   message. */

/* unknown (1<<3) */

#define NTLMFLAG_NEGOTIATE_SIGN                  (1<<4)

/* Specifies that authenticated communication between the client and server

   should carry a digital signature (message integrity). */

#define NTLMFLAG_NEGOTIATE_SEAL                  (1<<5)

/* Specifies that authenticated communication between the client and server

   should be encrypted (message confidentiality). */

#define NTLMFLAG_NEGOTIATE_DATAGRAM_STYLE        (1<<6)

/* Indicates that datagram authentication is being used. */

#define NTLMFLAG_NEGOTIATE_LM_KEY                (1<<7)

/* Indicates that the LAN Manager session key should be used for signing and

   sealing authenticated communications. */

#define NTLMFLAG_NEGOTIATE_NTLM_KEY              (1<<9)

/* Indicates that NTLM authentication is being used. */

/* unknown (1<<10) */

#define NTLMFLAG_NEGOTIATE_ANONYMOUS             (1<<11)

/* Sent by the client in the Type 3 message to indicate that an anonymous

   context has been established. This also affects the response fields. */

#define NTLMFLAG_NEGOTIATE_DOMAIN_SUPPLIED       (1<<12)

/* Sent by the client in the Type 1 message to indicate that a desired

   authentication realm is included in the message. */

#define NTLMFLAG_NEGOTIATE_WORKSTATION_SUPPLIED  (1<<13)

/* Sent by the client in the Type 1 message to indicate that the client

   workstation's name is included in the message. */

#define NTLMFLAG_NEGOTIATE_LOCAL_CALL            (1<<14)

/* Sent by the server to indicate that the server and client are on the same

   machine. Implies that the client may use a pre-established local security

   context rather than responding to the challenge. */

#define NTLMFLAG_NEGOTIATE_ALWAYS_SIGN           (1<<15)

/* Indicates that authenticated communication between the client and server

   should be signed with a "dummy" signature. */

#define NTLMFLAG_TARGET_TYPE_DOMAIN              (1<<16)

/* Sent by the server in the Type 2 message to indicate that the target

   authentication realm is a domain. */

#define NTLMFLAG_TARGET_TYPE_SERVER              (1<<17)

/* Sent by the server in the Type 2 message to indicate that the target

   authentication realm is a server. */

#define NTLMFLAG_TARGET_TYPE_SHARE               (1<<18)

/* Sent by the server in the Type 2 message to indicate that the target

   authentication realm is a share. Presumably, this is for share-level

   authentication. Usage is unclear. */

#define NTLMFLAG_NEGOTIATE_NTLM2_KEY             (1<<19)

/* Indicates that the NTLM2 signing and sealing scheme should be used for

   protecting authenticated communications. */

#define NTLMFLAG_REQUEST_INIT_RESPONSE           (1<<20)

/* unknown purpose */

#define NTLMFLAG_REQUEST_ACCEPT_RESPONSE         (1<<21)

/* unknown purpose */

#define NTLMFLAG_REQUEST_NONNT_SESSION_KEY       (1<<22)

/* unknown purpose */

#define NTLMFLAG_NEGOTIATE_TARGET_INFO           (1<<23)

/* Sent by the server in the Type 2 message to indicate that it is including a

   Target Information block in the message. */

/* unknown (1<24) */

/* unknown (1<25) */

/* unknown (1<26) */

/* unknown (1<27) */

/* unknown (1<28) */

#define NTLMFLAG_NEGOTIATE_128                   (1<<29)

/* Indicates that 128-bit encryption is supported. */

#define NTLMFLAG_NEGOTIATE_KEY_EXCHANGE          (1<<30)

/* Indicates that the client will provide an encrypted master key in

   the "Session Key" field of the Type 3 message. */

#define NTLMFLAG_NEGOTIATE_56                    (1<<31)

/* Indicates that 56-bit encryption is supported. */

/* "NTLMSSP" signature is always in ASCII regardless of the platform */

#define NTLMSSP_SIGNATURE "\x4e\x54\x4c\x4d\x53\x53\x50"

#if DEBUG_ME

#define DEBUG_OUT(x) x

static void ntlm_print_flags(FILE *handle, unsigned long flags)

{

  if(flags & NTLMFLAG_NEGOTIATE_UNICODE)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_UNICODE ");

  if(flags & NTLMFLAG_NEGOTIATE_OEM)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_OEM ");

  if(flags & NTLMFLAG_REQUEST_TARGET)

    curl_mfprintf(handle, "NTLMFLAG_REQUEST_TARGET ");

  if(flags & (1 << 3))

    curl_mfprintf(handle, "NTLMFLAG_UNKNOWN_3 ");

  if(flags & NTLMFLAG_NEGOTIATE_SIGN)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_SIGN ");

  if(flags & NTLMFLAG_NEGOTIATE_SEAL)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_SEAL ");

  if(flags & NTLMFLAG_NEGOTIATE_DATAGRAM_STYLE)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_DATAGRAM_STYLE ");

  if(flags & NTLMFLAG_NEGOTIATE_LM_KEY)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_LM_KEY ");

  if(flags & NTLMFLAG_NEGOTIATE_NTLM_KEY)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_NTLM_KEY ");

  if(flags & (1 << 10))

    curl_mfprintf(handle, "NTLMFLAG_UNKNOWN_10 ");

  if(flags & NTLMFLAG_NEGOTIATE_ANONYMOUS)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_ANONYMOUS ");

  if(flags & NTLMFLAG_NEGOTIATE_DOMAIN_SUPPLIED)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_DOMAIN_SUPPLIED ");

  if(flags & NTLMFLAG_NEGOTIATE_WORKSTATION_SUPPLIED)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_WORKSTATION_SUPPLIED ");

  if(flags & NTLMFLAG_NEGOTIATE_LOCAL_CALL)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_LOCAL_CALL ");

  if(flags & NTLMFLAG_NEGOTIATE_ALWAYS_SIGN)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_ALWAYS_SIGN ");

  if(flags & NTLMFLAG_TARGET_TYPE_DOMAIN)

    curl_mfprintf(handle, "NTLMFLAG_TARGET_TYPE_DOMAIN ");

  if(flags & NTLMFLAG_TARGET_TYPE_SERVER)

    curl_mfprintf(handle, "NTLMFLAG_TARGET_TYPE_SERVER ");

  if(flags & NTLMFLAG_TARGET_TYPE_SHARE)

    curl_mfprintf(handle, "NTLMFLAG_TARGET_TYPE_SHARE ");

  if(flags & NTLMFLAG_NEGOTIATE_NTLM2_KEY)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_NTLM2_KEY ");

  if(flags & NTLMFLAG_REQUEST_INIT_RESPONSE)

    curl_mfprintf(handle, "NTLMFLAG_REQUEST_INIT_RESPONSE ");

  if(flags & NTLMFLAG_REQUEST_ACCEPT_RESPONSE)

    curl_mfprintf(handle, "NTLMFLAG_REQUEST_ACCEPT_RESPONSE ");

  if(flags & NTLMFLAG_REQUEST_NONNT_SESSION_KEY)

    curl_mfprintf(handle, "NTLMFLAG_REQUEST_NONNT_SESSION_KEY ");

  if(flags & NTLMFLAG_NEGOTIATE_TARGET_INFO)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_TARGET_INFO ");

  if(flags & (1 << 24))

    curl_mfprintf(handle, "NTLMFLAG_UNKNOWN_24 ");

  if(flags & (1 << 25))

    curl_mfprintf(handle, "NTLMFLAG_UNKNOWN_25 ");

  if(flags & (1 << 26))

    curl_mfprintf(handle, "NTLMFLAG_UNKNOWN_26 ");

  if(flags & (1 << 27))

    curl_mfprintf(handle, "NTLMFLAG_UNKNOWN_27 ");

  if(flags & (1 << 28))

    curl_mfprintf(handle, "NTLMFLAG_UNKNOWN_28 ");

  if(flags & NTLMFLAG_NEGOTIATE_128)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_128 ");

  if(flags & NTLMFLAG_NEGOTIATE_KEY_EXCHANGE)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_KEY_EXCHANGE ");

  if(flags & NTLMFLAG_NEGOTIATE_56)

    curl_mfprintf(handle, "NTLMFLAG_NEGOTIATE_56 ");

}

static void ntlm_print_hex(FILE *handle, const char *buf, size_t len)

{

  const char *p = buf;

  (void)handle;

  curl_mfprintf(stderr, "0x");

  while(len-- > 0)

    curl_mfprintf(stderr, "%02.2x", (unsigned int)*p++);

}

#else

#define DEBUG_OUT(x) Curl_nop_stmt

#endif

/*

 * ntlm_decode_type2_target()

 *

 * This is used to decode the "target info" in the NTLM type-2 message

 * received.

 *

 * Parameters:

 *

 * data      [in]     - The session handle.

 * type2ref  [in]     - The type-2 message.

 * ntlm      [in/out] - The NTLM data struct being used and modified.

 *

 * Returns CURLE_OK on success.

 */

static CURLcode ntlm_decode_type2_target(struct Curl_easy *data,

                                         const struct bufref *type2ref,

                                         struct ntlmdata *ntlm)

{

  unsigned short target_info_len = 0;

  unsigned int target_info_offset = 0;

  const unsigned char *type2 = Curl_bufref_uptr(type2ref);

  size_t type2len = Curl_bufref_len(type2ref);

#ifdef CURL_DISABLE_VERBOSE_STRINGS

  (void)data;

#endif

  if(type2len >= 48) {

    target_info_len = Curl_read16_le(&type2[40]);

    target_info_offset = Curl_read32_le(&type2[44]);

    if(target_info_len > 0) {

      if((target_info_offset > type2len) ||

         (target_info_offset + target_info_len) > type2len ||

         target_info_offset < 48) {

        infof(data, "NTLM handshake failure (bad type-2 message). "

              "Target Info Offset Len is set incorrect by the peer");

        return CURLE_BAD_CONTENT_ENCODING;

      }

      curlx_free(ntlm->target_info); /* replace any previous data */

      ntlm->target_info = Curl_memdup(&type2[target_info_offset],

                                      target_info_len);

      if(!ntlm->target_info)

        return CURLE_OUT_OF_MEMORY;

    }

  }

  ntlm->target_info_len = target_info_len;

  return CURLE_OK;

}

/*

  NTLM message structure notes:

  A 'short' is a 'network short', a little-endian 16-bit unsigned value.

  A 'long' is a 'network long', a little-endian, 32-bit unsigned value.

  A 'security buffer' represents a triplet used to point to a buffer,

  consisting of two shorts and one long:

    1. A 'short' containing the length of the buffer content in bytes.

    2. A 'short' containing the allocated space for the buffer in bytes.

    3. A 'long' containing the offset to the start of the buffer in bytes,

       from the beginning of the NTLM message.

*/

/*

 * Curl_auth_is_ntlm_supported()

 *

 * This is used to evaluate if NTLM is supported.

 *

 * Parameters: None

 *

 * Returns TRUE as NTLM as handled by libcurl.

 */

bool Curl_auth_is_ntlm_supported(void)

{

  return TRUE;

}

/*

 * Curl_auth_decode_ntlm_type2_message()

 *

 * This is used to decode an NTLM type-2 message. The raw NTLM message is

 * checked * for validity before the appropriate data for creating a type-3

 * message is * written to the given NTLM data structure.

 *

 * Parameters:

 *

 * data     [in]     - The session handle.

 * type2ref [in]     - The type-2 message.

 * ntlm     [in/out] - The NTLM data struct being used and modified.

 *

 * Returns CURLE_OK on success.

 */

CURLcode Curl_auth_decode_ntlm_type2_message(struct Curl_easy *data,

                                             const struct bufref *type2ref,

                                             struct ntlmdata *ntlm)

{

  static const char type2_marker[] = { 0x02, 0x00, 0x00, 0x00 };

  /* NTLM type-2 message structure:

          Index  Description            Content

            0    NTLMSSP Signature      Null-terminated ASCII "NTLMSSP"

                                        (0x4e544c4d53535000)

            8    NTLM Message Type      long (0x02000000)

           12    Target Name            security buffer

           20    Flags                  long

           24    Challenge              8 bytes

          (32)   Context                8 bytes (two consecutive longs) (*)

          (40)   Target Information     security buffer (*)

          (48)   OS Version Structure   8 bytes (*)

  32 (48) (56)   Start of data block    (*)

                                        (*) -> Optional

  */

  CURLcode result = CURLE_OK;

  const unsigned char *type2 = Curl_bufref_uptr(type2ref);

  size_t type2len = Curl_bufref_len(type2ref);

#ifdef CURL_DISABLE_VERBOSE_STRINGS

  (void)data;

#endif

  ntlm->flags = 0;

  if((type2len < 32) ||

     (memcmp(type2, NTLMSSP_SIGNATURE, 8) != 0) ||

     (memcmp(type2 + 8, type2_marker, sizeof(type2_marker)) != 0)) {

    /* This was not a good enough type-2 message */

    infof(data, "NTLM handshake failure (bad type-2 message)");

    return CURLE_BAD_CONTENT_ENCODING;

  }

  ntlm->flags = Curl_read32_le(&type2[20]);

  memcpy(ntlm->nonce, &type2[24], 8);

  if(ntlm->flags & NTLMFLAG_NEGOTIATE_TARGET_INFO) {

    result = ntlm_decode_type2_target(data, type2ref, ntlm);

    if(result) {

      infof(data, "NTLM handshake failure (bad type-2 message)");

      return result;

    }

  }

  DEBUG_OUT({

    curl_mfprintf(stderr, "**** TYPE2 header flags=0x%08.8lx ", ntlm->flags);

    ntlm_print_flags(stderr, ntlm->flags);

    curl_mfprintf(stderr, "\n                  nonce=");

    ntlm_print_hex(stderr, (char *)ntlm->nonce, 8);

    curl_mfprintf(stderr, "\n****\n");

    curl_mfprintf(stderr, "**** Header %s\n ", header);

  });

  return result;

}

/* copy the source to the destination and fill in zeroes in every

   other destination byte! */

static void unicodecpy(unsigned char *dest, const char *src, size_t length)

{

  size_t i;

  for(i = 0; i < length; i++) {

    dest[2 * i] = (unsigned char)src[i];

    dest[2 * i + 1] = '\0';

  }

}

/*

 * Curl_auth_create_ntlm_type1_message()

 *

 * This is used to generate an NTLM type-1 message ready for sending to the

 * recipient using the appropriate compile time crypto API.

 *

 * Parameters:

 *

 * data    [in]     - The session handle.

 * userp   [in]     - The username in the format User or Domain\User.

 * passwdp [in]     - The user's password.

 * service [in]     - The service type such as http, smtp, pop or imap.

 * host    [in]     - The hostname.

 * ntlm    [in/out] - The NTLM data struct being used and modified.

 * out     [out]    - The result storage.

 *

 * Returns CURLE_OK on success.

 */

CURLcode Curl_auth_create_ntlm_type1_message(struct Curl_easy *data,

                                             const char *userp,

                                             const char *passwdp,

                                             const char *service,

                                             const char *hostname,

                                             struct ntlmdata *ntlm,

                                             struct bufref *out)

{

  /* NTLM type-1 message structure:

       Index  Description            Content

         0    NTLMSSP Signature      Null-terminated ASCII "NTLMSSP"

                                     (0x4e544c4d53535000)

         8    NTLM Message Type      long (0x01000000)

        12    Flags                  long

       (16)   Supplied Domain        security buffer (*)

       (24)   Supplied Workstation   security buffer (*)

       (32)   OS Version Structure   8 bytes (*)

  (32) (40)   Start of data block    (*)

                                     (*) -> Optional

  */

  size_t size;

  char *ntlmbuf;

  const char *host = "";              /* empty */

  const char *domain = "";            /* empty */

  size_t hostlen = 0;

  size_t domlen = 0;

  size_t hostoff = 0;

  size_t domoff = hostoff + hostlen;  /* This is 0: remember that host and

                                         domain are empty */

  (void)data;

  (void)userp;

  (void)passwdp;

  (void)service;

  (void)hostname;

  /* Clean up any former leftovers and initialise to defaults */

  Curl_auth_cleanup_ntlm(ntlm);

  ntlmbuf = curl_maprintf(NTLMSSP_SIGNATURE "%c"

                          "\x01%c%c%c" /* 32-bit type = 1 */

                          "%c%c%c%c"   /* 32-bit NTLM flag field */

                          "%c%c"       /* domain length */

                          "%c%c"       /* domain allocated space */

                          "%c%c"       /* domain name offset */

                          "%c%c"       /* 2 zeroes */

                          "%c%c"       /* host length */

                          "%c%c"       /* host allocated space */

                          "%c%c"       /* hostname offset */

                          "%c%c"       /* 2 zeroes */

                          "%s"         /* hostname */

                          "%s",        /* domain string */

                          0,           /* trailing zero */

                          0, 0, 0,     /* part of type-1 long */

                          LONGQUARTET(NTLMFLAG_NEGOTIATE_OEM |

                                      NTLMFLAG_REQUEST_TARGET |

                                      NTLMFLAG_NEGOTIATE_NTLM_KEY |

                                      NTLMFLAG_NEGOTIATE_NTLM2_KEY |

                                      NTLMFLAG_NEGOTIATE_ALWAYS_SIGN),

                          SHORTPAIR(domlen),

                          SHORTPAIR(domlen),

                          SHORTPAIR(domoff),

                          0, 0,

                          SHORTPAIR(hostlen),

                          SHORTPAIR(hostlen),

                          SHORTPAIR(hostoff),

                          0, 0,

                          host,  /* this is empty */

                          domain /* this is empty */);

  if(!ntlmbuf)

    return CURLE_OUT_OF_MEMORY;

  /* Initial packet length */

  size = 32 + hostlen + domlen;

  DEBUG_OUT({

    curl_mfprintf(stderr, "* TYPE1 header flags=0x%02.2x%02.2x%02.2x%02.2x "

                  "0x%08.8x ",

                  LONGQUARTET(NTLMFLAG_NEGOTIATE_OEM |

                              NTLMFLAG_REQUEST_TARGET |

                              NTLMFLAG_NEGOTIATE_NTLM_KEY |

                              NTLMFLAG_NEGOTIATE_NTLM2_KEY |

                              NTLMFLAG_NEGOTIATE_ALWAYS_SIGN),

                  NTLMFLAG_NEGOTIATE_OEM |

                  NTLMFLAG_REQUEST_TARGET |

                  NTLMFLAG_NEGOTIATE_NTLM_KEY |

                  NTLMFLAG_NEGOTIATE_NTLM2_KEY |

                  NTLMFLAG_NEGOTIATE_ALWAYS_SIGN);

    ntlm_print_flags(stderr,

                     NTLMFLAG_NEGOTIATE_OEM |

                     NTLMFLAG_REQUEST_TARGET |

                     NTLMFLAG_NEGOTIATE_NTLM_KEY |

                     NTLMFLAG_NEGOTIATE_NTLM2_KEY |

                     NTLMFLAG_NEGOTIATE_ALWAYS_SIGN);

    curl_mfprintf(stderr, "\n****\n");

  });

  Curl_bufref_set(out, ntlmbuf, size, curl_free);

  return CURLE_OK;

}

/*

 * Curl_auth_create_ntlm_type3_message()

 *

 * This is used to generate an already encoded NTLM type-3 message ready for

 * sending to the recipient using the appropriate compile time crypto API.

 *

 * Parameters:

 *

 * data    [in]     - The session handle.

 * userp   [in]     - The username in the format User or Domain\User.

 * passwdp [in]     - The user's password.

 * ntlm    [in/out] - The NTLM data struct being used and modified.

 * out     [out]    - The result storage.

 *

 * Returns CURLE_OK on success.

 */

CURLcode Curl_auth_create_ntlm_type3_message(struct Curl_easy *data,

                                             const char *userp,

                                             const char *passwdp,

                                             struct ntlmdata *ntlm,

                                             struct bufref *out)

{

  /* NTLM type-3 message structure:

          Index  Description            Content

            0    NTLMSSP Signature      Null-terminated ASCII "NTLMSSP"

                                        (0x4e544c4d53535000)

            8    NTLM Message Type      long (0x03000000)

           12    LM/LMv2 Response       security buffer

           20    NTLM/NTLMv2 Response   security buffer

           28    Target Name            security buffer

           36    username              security buffer

           44    Workstation Name       security buffer

          (52)   Session Key            security buffer (*)

          (60)   Flags                  long (*)

          (64)   OS Version Structure   8 bytes (*)

  52 (64) (72)   Start of data block

                                          (*) -> Optional

  */

  CURLcode result = CURLE_OK;

  size_t size;

  unsigned char ntlmbuf[NTLM_BUFSIZE];

  unsigned int lmrespoff;

  unsigned char lmresp[24]; /* fixed-size */

  unsigned int ntrespoff;

  unsigned int ntresplen = 24;

  unsigned char ntresp[24]; /* fixed-size */

  unsigned char *ptr_ntresp = &ntresp[0];

  unsigned char *ntlmv2resp = NULL;

  bool unicode = (ntlm->flags & NTLMFLAG_NEGOTIATE_UNICODE);

  /* The fixed hostname we provide, in order to not leak our real local host

     name. Copy the name used by Firefox. */

  static const char host[] = "WORKSTATION";

  const char *user;

  const char *domain = "";

  size_t hostoff = 0;

  size_t useroff = 0;

  size_t domoff = 0;

  size_t hostlen = 0;

  size_t userlen = 0;

  size_t domlen = 0;

  memset(lmresp, 0, sizeof(lmresp));

  memset(ntresp, 0, sizeof(ntresp));

  user = strchr(userp, '\\');

  if(!user)

    user = strchr(userp, '/');

  if(user) {

    domain = userp;

    domlen = (user - domain);

    user++;

  }

  else

    user = userp;

  userlen = strlen(user);

  hostlen = sizeof(host) - 1;

  if(ntlm->flags & NTLMFLAG_NEGOTIATE_NTLM2_KEY) {

    unsigned char ntbuffer[0x18];

    unsigned char entropy[8];

    unsigned char ntlmv2hash[0x18];

    /* Full NTLM version 2

       Although this cannot be negotiated, it is used here if available, as

       servers featuring extended security are likely supporting also

       NTLMv2. */

    result = Curl_rand(data, entropy, 8);

    if(result)

      return result;

    result = Curl_ntlm_core_mk_nt_hash(passwdp, ntbuffer);

    if(result)

      return result;

    result = Curl_ntlm_core_mk_ntlmv2_hash(user, userlen, domain, domlen,

                                           ntbuffer, ntlmv2hash);

    if(result)

      return result;

    /* LMv2 response */

    result = Curl_ntlm_core_mk_lmv2_resp(ntlmv2hash, entropy,

                                         &ntlm->nonce[0], lmresp);

    if(result)

      return result;

    /* NTLMv2 response */

    result = Curl_ntlm_core_mk_ntlmv2_resp(ntlmv2hash, entropy,

                                           ntlm, &ntlmv2resp, &ntresplen);

    if(result)

      return result;

    ptr_ntresp = ntlmv2resp;

  }

  else {

    unsigned char ntbuffer[0x18];

    unsigned char lmbuffer[0x18];

    /* NTLM version 1 */

    result = Curl_ntlm_core_mk_nt_hash(passwdp, ntbuffer);

    if(result)

      return result;

    Curl_ntlm_core_lm_resp(ntbuffer, &ntlm->nonce[0], ntresp);

    result = Curl_ntlm_core_mk_lm_hash(passwdp, lmbuffer);

    if(result)

      return result;

    Curl_ntlm_core_lm_resp(lmbuffer, &ntlm->nonce[0], lmresp);

    ntlm->flags &= ~(unsigned int)NTLMFLAG_NEGOTIATE_NTLM2_KEY;

    /* A safer but less compatible alternative is:

     *   Curl_ntlm_core_lm_resp(ntbuffer, &ntlm->nonce[0], lmresp);

     * See https://davenport.sourceforge.net/ntlm.html#ntlmVersion2 */

  }

  if(unicode) {

    domlen = domlen * 2;

    userlen = userlen * 2;

    hostlen = hostlen * 2;

  }

  lmrespoff = 64; /* size of the message header */

  ntrespoff = lmrespoff + 0x18;

  domoff = ntrespoff + ntresplen;

  useroff = domoff + domlen;

  hostoff = useroff + userlen;

  /* Create the big type-3 message binary blob */

  size = curl_msnprintf((char *)ntlmbuf, NTLM_BUFSIZE,

                         NTLMSSP_SIGNATURE "%c"

                         "\x03%c%c%c"  /* 32-bit type = 3 */

                         "%c%c"  /* LanManager length */

                         "%c%c"  /* LanManager allocated space */

                         "%c%c"  /* LanManager offset */

                         "%c%c"  /* 2 zeroes */

                         "%c%c"  /* NT-response length */

                         "%c%c"  /* NT-response allocated space */

                         "%c%c"  /* NT-response offset */

                         "%c%c"  /* 2 zeroes */

                         "%c%c"  /* domain length */

                         "%c%c"  /* domain allocated space */

                         "%c%c"  /* domain name offset */

                         "%c%c"  /* 2 zeroes */

                         "%c%c"  /* user length */

                         "%c%c"  /* user allocated space */

                         "%c%c"  /* user offset */

                         "%c%c"  /* 2 zeroes */

                         "%c%c"  /* host length */

                         "%c%c"  /* host allocated space */

                         "%c%c"  /* host offset */

                         "%c%c"  /* 2 zeroes */

                         "%c%c"  /* session key length (unknown purpose) */

                         "%c%c"  /* session key allocated space

                                    (unknown purpose) */

                         "%c%c"  /* session key offset (unknown purpose) */

                         "%c%c"  /* 2 zeroes */

                         "%c%c%c%c",  /* flags */

                         /* domain string */

                         /* user string */

                         /* host string */

                         /* LanManager response */

                         /* NT response */

                         0,                /* null-termination */

                         0, 0, 0,          /* type-3 long, the 24 upper bits */

                         SHORTPAIR(0x18),  /* LanManager response length,

                                              twice */

                         SHORTPAIR(0x18),

                         SHORTPAIR(lmrespoff),

                         0x0, 0x0,

                         SHORTPAIR(ntresplen),  /* NT-response length, twice */

                         SHORTPAIR(ntresplen),

                         SHORTPAIR(ntrespoff),

                         0x0, 0x0,

                         SHORTPAIR(domlen),

                         SHORTPAIR(domlen),

                         SHORTPAIR(domoff),

                         0x0, 0x0,

                         SHORTPAIR(userlen),

                         SHORTPAIR(userlen),

                         SHORTPAIR(useroff),

                         0x0, 0x0,

                         SHORTPAIR(hostlen),

                         SHORTPAIR(hostlen),

                         SHORTPAIR(hostoff),

                         0x0, 0x0,

                         0x0, 0x0,

                         0x0, 0x0,

                         0x0, 0x0,

                         0x0, 0x0,

                         LONGQUARTET(ntlm->flags));

  DEBUGASSERT(size == 64);

  DEBUGASSERT(size == (size_t)lmrespoff);

  /* We append the binary hashes */

  if(size < (NTLM_BUFSIZE - 0x18)) {

    memcpy(&ntlmbuf[size], lmresp, 0x18);

    size += 0x18;

  }

  DEBUG_OUT({

    curl_mfprintf(stderr, "**** TYPE3 header lmresp=");

    ntlm_print_hex(stderr, (char *)&ntlmbuf[lmrespoff], 0x18);

  });

  /* ntresplen + size should not be risking an integer overflow here */

  if(ntresplen + size > sizeof(ntlmbuf)) {

    failf(data, "incoming NTLM message too big");

    result = CURLE_TOO_LARGE;

    goto error;

  }

  DEBUGASSERT(size == (size_t)ntrespoff);

  memcpy(&ntlmbuf[size], ptr_ntresp, ntresplen);

  size += ntresplen;

  DEBUG_OUT({

    curl_mfprintf(stderr, "\n   ntresp=");

    ntlm_print_hex(stderr, (char *)&ntlmbuf[ntrespoff], ntresplen);

  });

  DEBUG_OUT({

    curl_mfprintf(stderr, "\n   flags=0x%02.2x%02.2x%02.2x%02.2x 0x%08.8x ",

                  LONGQUARTET(ntlm->flags), ntlm->flags);

    ntlm_print_flags(stderr, ntlm->flags);

    curl_mfprintf(stderr, "\n****\n");

  });

  /* Make sure that the domain, user and host strings fit in the

     buffer before we copy them there. */

  if(size + userlen + domlen + hostlen >= NTLM_BUFSIZE) {

    failf(data, "user + domain + hostname too big for NTLM");

    result = CURLE_TOO_LARGE;

    goto error;

  }

  DEBUGASSERT(size == domoff);

  if(unicode)

    unicodecpy(&ntlmbuf[size], domain, domlen / 2);

  else

    memcpy(&ntlmbuf[size], domain, domlen);

  size += domlen;

  DEBUGASSERT(size == useroff);

  if(unicode)

    unicodecpy(&ntlmbuf[size], user, userlen / 2);

  else

    memcpy(&ntlmbuf[size], user, userlen);

  size += userlen;

  DEBUGASSERT(size == hostoff);

  if(unicode)

    unicodecpy(&ntlmbuf[size], host, hostlen / 2);

  else

    memcpy(&ntlmbuf[size], host, hostlen);

  size += hostlen;

  /* Return the binary blob. */

  result = Curl_bufref_memdup0(out, ntlmbuf, size);

error:

  curlx_free(ntlmv2resp);  /* Free the dynamic buffer allocated for NTLMv2 */

  Curl_auth_cleanup_ntlm(ntlm);

  return result;

}

/*

 * Curl_auth_cleanup_ntlm()

 *

 * This is used to clean up the NTLM specific data.

 *

 * Parameters:

 *

 * ntlm    [in/out] - The NTLM data struct being cleaned up.

 *

 */

void Curl_auth_cleanup_ntlm(struct ntlmdata *ntlm)

{

  /* Free the target info */

  Curl_safefree(ntlm->target_info);

  /* Reset any variables */

  ntlm->target_info_len = 0;

}

#endif /* USE_NTLM && !USE_WINDOWS_SSPI */