/**
 * Author......: See docs/credits.txt
 * License.....: MIT
 */

#include "common.h"
#include "types.h"
#include "modules.h"
#include "bitops.h"
#include "convert.h"
#include "shared.h"

static const u32   ATTACK_EXEC    = ATTACK_EXEC_INSIDE_KERNEL;
static const u32   DGST_POS0      = 0;
static const u32   DGST_POS1      = 1;
static const u32   DGST_POS2      = 2;
static const u32   DGST_POS3      = 3;
static const u32   DGST_SIZE      = DGST_SIZE_4_4;
static const u32   HASH_CATEGORY  = HASH_CATEGORY_NETWORK_PROTOCOL;
static const char *HASH_NAME      = "Kerberos 5, etype 23, AS-REQ Pre-Auth";
static const u64   KERN_TYPE      = 7500;
static const u32   OPTI_TYPE      = OPTI_TYPE_ZERO_BYTE
                                  | OPTI_TYPE_NOT_ITERATED;
static const u64   OPTS_TYPE      = OPTS_TYPE_PT_GENERATE_LE
                                  | OPTS_TYPE_MAXIMUM_THREADS;
static const u32   SALT_TYPE      = SALT_TYPE_EMBEDDED;
static const char *ST_PASS        = "hashcat";
static const char *ST_HASH        = "$krb5pa$23$user$realm$salt$5cbb0c882a2b26956e81644edbdb746326f4f5f0e947144fb3095dffe4b4b03e854fc1d631323632303636373330383333353630";

u32         module_attack_exec    (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return ATTACK_EXEC;     }
u32         module_dgst_pos0      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return DGST_POS0;       }
u32         module_dgst_pos1      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return DGST_POS1;       }
u32         module_dgst_pos2      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return DGST_POS2;       }
u32         module_dgst_pos3      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return DGST_POS3;       }
u32         module_dgst_size      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return DGST_SIZE;       }
u32         module_hash_category  (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return HASH_CATEGORY;   }
const char *module_hash_name      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return HASH_NAME;       }
u64         module_kern_type      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return KERN_TYPE;       }
u32         module_opti_type      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return OPTI_TYPE;       }
u64         module_opts_type      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return OPTS_TYPE;       }
u32         module_salt_type      (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return SALT_TYPE;       }
const char *module_st_hash        (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return ST_HASH;         }
const char *module_st_pass        (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra) { return ST_PASS;         }

typedef struct krb5pa
{
  u32 user[16];
  u32 realm[16];
  u32 salt[32];
  u32 timestamp[16];
  u32 checksum[4];

} krb5pa_t;

static const char *SIGNATURE_KRB5PA = "$krb5pa$23$";

char *module_jit_build_options (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra, MAYBE_UNUSED const hashes_t *hashes, MAYBE_UNUSED const hc_device_param_t *device_param)
{
  char *jit_build_options = NULL;

  u32 native_threads = 0;

  if (device_param->opencl_device_type & CL_DEVICE_TYPE_CPU)
  {
    native_threads = 1;
  }
  else if (device_param->opencl_device_type & CL_DEVICE_TYPE_GPU)
  {
    #if defined (__APPLE__)

    native_threads = 32;

    #else

    if (device_param->device_local_mem_size < 49152)
    {
      native_threads = MIN (device_param->kernel_preferred_wgs_multiple, 32); // We can't just set 32, because Intel GPU need 8
    }
    else
    {
      native_threads = device_param->kernel_preferred_wgs_multiple;
    }

    #endif
  }

  hc_asprintf (&jit_build_options, "-D FIXED_LOCAL_SIZE=%u -D _unroll", native_threads);

  return jit_build_options;
}

u64 module_esalt_size (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const user_options_t *user_options, MAYBE_UNUSED const user_options_extra_t *user_options_extra)
{
  const u64 esalt_size = (const u64) sizeof (krb5pa_t);

  return esalt_size;
}

int module_hash_decode (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED void *digest_buf, MAYBE_UNUSED salt_t *salt, MAYBE_UNUSED void *esalt_buf, MAYBE_UNUSED void *hook_salt_buf, MAYBE_UNUSED hashinfo_t *hash_info, const char *line_buf, MAYBE_UNUSED const int line_len)
{
  u32 *digest = (u32 *) digest_buf;

  krb5pa_t *krb5pa = (krb5pa_t *) esalt_buf;

  hc_token_t token;

  token.token_cnt  = 6;

  token.signatures_cnt    = 1;
  token.signatures_buf[0] = SIGNATURE_KRB5PA;

  token.len[0]     = 11;
  token.attr[0]    = TOKEN_ATTR_FIXED_LENGTH
                   | TOKEN_ATTR_VERIFY_SIGNATURE;

  token.len_min[1] = 0;
  token.len_max[1] = 64;
  token.sep[1]     = '$';
  token.attr[1]    = TOKEN_ATTR_VERIFY_LENGTH;

  token.len_min[2] = 0;
  token.len_max[2] = 64;
  token.sep[2]     = '$';
  token.attr[2]    = TOKEN_ATTR_VERIFY_LENGTH;

  token.len_min[3] = 0;
  token.len_max[3] = 128;
  token.sep[3]     = '$';
  token.attr[3]    = TOKEN_ATTR_VERIFY_LENGTH;

  token.len[4]     = 72;
  token.attr[4]    = TOKEN_ATTR_FIXED_LENGTH
                   | TOKEN_ATTR_VERIFY_HEX;

  token.len[5]     = 32;
  token.attr[5]    = TOKEN_ATTR_FIXED_LENGTH
                   | TOKEN_ATTR_VERIFY_HEX;

  const int rc_tokenizer = input_tokenizer ((const u8 *) line_buf, line_len, &token);

  if (rc_tokenizer != PARSER_OK) return (rc_tokenizer);

  const u8 *user_pos  = token.buf[1];
  const u8 *realm_pos = token.buf[2];
  const u8 *salt_pos  = token.buf[3];

  const int user_len  = token.len[1];
  const int realm_len = token.len[2];
  const int salt_len  = token.len[3];

  /**
   * copy data
   */

  memcpy (krb5pa->user,  user_pos,  user_len);
  memcpy (krb5pa->realm, realm_pos, realm_len);
  memcpy (krb5pa->salt,  salt_pos,  salt_len);

  /**
   * decode data
   */

  const u8 *timestamp_pos = token.buf[4];

  u8 *timestamp_ptr = (u8 *) krb5pa->timestamp;

  for (int i = 0; i < 72; i += 2)
  {
    const u8 p0 = timestamp_pos[i + 0];
    const u8 p1 = timestamp_pos[i + 1];

    *timestamp_ptr++ = hex_convert (p1) << 0
                     | hex_convert (p0) << 4;
  }

  const u8 *checksum_pos = token.buf[5];

  u8 *checksum_ptr = (u8 *) krb5pa->checksum;

  for (int i = 0; i < 32; i += 2)
  {
    const u8 p0 = checksum_pos[i + 0];
    const u8 p1 = checksum_pos[i + 1];

    *checksum_ptr++ = hex_convert (p1) << 0
                    | hex_convert (p0) << 4;
  }

  /**
   * copy some data to generic buffers to make sorting happy
   */

  salt->salt_buf[0] = krb5pa->timestamp[0];
  salt->salt_buf[1] = krb5pa->timestamp[1];
  salt->salt_buf[2] = krb5pa->timestamp[2];
  salt->salt_buf[3] = krb5pa->timestamp[3];
  salt->salt_buf[4] = krb5pa->timestamp[4];
  salt->salt_buf[5] = krb5pa->timestamp[5];
  salt->salt_buf[6] = krb5pa->timestamp[6];
  salt->salt_buf[7] = krb5pa->timestamp[7];
  salt->salt_buf[8] = krb5pa->timestamp[8];

  salt->salt_len = 36;

  digest[0] = krb5pa->checksum[0];
  digest[1] = krb5pa->checksum[1];
  digest[2] = krb5pa->checksum[2];
  digest[3] = krb5pa->checksum[3];

  return (PARSER_OK);
}

int module_hash_encode (MAYBE_UNUSED const hashconfig_t *hashconfig, MAYBE_UNUSED const void *digest_buf, MAYBE_UNUSED const salt_t *salt, MAYBE_UNUSED const void *esalt_buf, MAYBE_UNUSED const void *hook_salt_buf, MAYBE_UNUSED const hashinfo_t *hash_info, char *line_buf, MAYBE_UNUSED const int line_size)
{
  const krb5pa_t *krb5pa = (const krb5pa_t *) esalt_buf;

  u8 *ptr_timestamp = (u8 *) krb5pa->timestamp;
  u8 *ptr_checksum  = (u8 *) krb5pa->checksum;

  char data[128] = { 0 };

  char *ptr_data = data;

  for (u32 i = 0; i < 36; i++, ptr_data += 2)
  {
    sprintf (ptr_data, "%02x", ptr_timestamp[i]);
  }

  for (u32 i = 0; i < 16; i++, ptr_data += 2)
  {
    sprintf (ptr_data, "%02x", ptr_checksum[i]);
  }

  *ptr_data = 0;

  const int line_len = snprintf (line_buf, line_size, "%s%s$%s$%s$%s",
    SIGNATURE_KRB5PA,
    (char *) krb5pa->user,
    (char *) krb5pa->realm,
    (char *) krb5pa->salt,
    data);

  return line_len;
}

void module_init (module_ctx_t *module_ctx)
{
  module_ctx->module_context_size             = MODULE_CONTEXT_SIZE_CURRENT;
  module_ctx->module_interface_version        = MODULE_INTERFACE_VERSION_CURRENT;

  module_ctx->module_attack_exec              = module_attack_exec;
  module_ctx->module_benchmark_esalt          = MODULE_DEFAULT;
  module_ctx->module_benchmark_hook_salt      = MODULE_DEFAULT;
  module_ctx->module_benchmark_mask           = MODULE_DEFAULT;
  module_ctx->module_benchmark_salt           = MODULE_DEFAULT;
  module_ctx->module_build_plain_postprocess  = MODULE_DEFAULT;
  module_ctx->module_deep_comp_kernel         = MODULE_DEFAULT;
  module_ctx->module_deprecated_notice        = MODULE_DEFAULT;
  module_ctx->module_dgst_pos0                = module_dgst_pos0;
  module_ctx->module_dgst_pos1                = module_dgst_pos1;
  module_ctx->module_dgst_pos2                = module_dgst_pos2;
  module_ctx->module_dgst_pos3                = module_dgst_pos3;
  module_ctx->module_dgst_size                = module_dgst_size;
  module_ctx->module_dictstat_disable         = MODULE_DEFAULT;
  module_ctx->module_esalt_size               = module_esalt_size;
  module_ctx->module_extra_buffer_size        = MODULE_DEFAULT;
  module_ctx->module_extra_tmp_size           = MODULE_DEFAULT;
  module_ctx->module_extra_tuningdb_block     = MODULE_DEFAULT;
  module_ctx->module_forced_outfile_format    = MODULE_DEFAULT;
  module_ctx->module_hash_binary_count        = MODULE_DEFAULT;
  module_ctx->module_hash_binary_parse        = MODULE_DEFAULT;
  module_ctx->module_hash_binary_save         = MODULE_DEFAULT;
  module_ctx->module_hash_decode_postprocess  = MODULE_DEFAULT;
  module_ctx->module_hash_decode_potfile      = MODULE_DEFAULT;
  module_ctx->module_hash_decode_zero_hash    = MODULE_DEFAULT;
  module_ctx->module_hash_decode              = module_hash_decode;
  module_ctx->module_hash_encode_status       = MODULE_DEFAULT;
  module_ctx->module_hash_encode_potfile      = MODULE_DEFAULT;
  module_ctx->module_hash_encode              = module_hash_encode;
  module_ctx->module_hash_init_selftest       = MODULE_DEFAULT;
  module_ctx->module_hash_mode                = MODULE_DEFAULT;
  module_ctx->module_hash_category            = module_hash_category;
  module_ctx->module_hash_name                = module_hash_name;
  module_ctx->module_hashes_count_min         = MODULE_DEFAULT;
  module_ctx->module_hashes_count_max         = MODULE_DEFAULT;
  module_ctx->module_hlfmt_disable            = MODULE_DEFAULT;
  module_ctx->module_hook_extra_param_size    = MODULE_DEFAULT;
  module_ctx->module_hook_extra_param_init    = MODULE_DEFAULT;
  module_ctx->module_hook_extra_param_term    = MODULE_DEFAULT;
  module_ctx->module_hook12                   = MODULE_DEFAULT;
  module_ctx->module_hook23                   = MODULE_DEFAULT;
  module_ctx->module_hook_salt_size           = MODULE_DEFAULT;
  module_ctx->module_hook_size                = MODULE_DEFAULT;
  module_ctx->module_jit_build_options        = module_jit_build_options;
  module_ctx->module_jit_cache_disable        = MODULE_DEFAULT;
  module_ctx->module_kernel_accel_max         = MODULE_DEFAULT;
  module_ctx->module_kernel_accel_min         = MODULE_DEFAULT;
  module_ctx->module_kernel_loops_max         = MODULE_DEFAULT;
  module_ctx->module_kernel_loops_min         = MODULE_DEFAULT;
  module_ctx->module_kernel_threads_max       = MODULE_DEFAULT;
  module_ctx->module_kernel_threads_min       = MODULE_DEFAULT;
  module_ctx->module_kern_type                = module_kern_type;
  module_ctx->module_kern_type_dynamic        = MODULE_DEFAULT;
  module_ctx->module_opti_type                = module_opti_type;
  module_ctx->module_opts_type                = module_opts_type;
  module_ctx->module_outfile_check_disable    = MODULE_DEFAULT;
  module_ctx->module_outfile_check_nocomp     = MODULE_DEFAULT;
  module_ctx->module_potfile_custom_check     = MODULE_DEFAULT;
  module_ctx->module_potfile_disable          = MODULE_DEFAULT;
  module_ctx->module_potfile_keep_all_hashes  = MODULE_DEFAULT;
  module_ctx->module_pwdump_column            = MODULE_DEFAULT;
  module_ctx->module_pw_max                   = MODULE_DEFAULT;
  module_ctx->module_pw_min                   = MODULE_DEFAULT;
  module_ctx->module_salt_max                 = MODULE_DEFAULT;
  module_ctx->module_salt_min                 = MODULE_DEFAULT;
  module_ctx->module_salt_type                = module_salt_type;
  module_ctx->module_separator                = MODULE_DEFAULT;
  module_ctx->module_st_hash                  = module_st_hash;
  module_ctx->module_st_pass                  = module_st_pass;
  module_ctx->module_tmp_size                 = MODULE_DEFAULT;
  module_ctx->module_unstable_warning         = MODULE_DEFAULT;
  module_ctx->module_warmup_disable           = MODULE_DEFAULT;
}