/**
 * 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_RAW_CIPHER_KPA;
static const char *HASH_NAME      = "ChaCha20";
static const u64   KERN_TYPE      = 15400;
static const u32   OPTI_TYPE      = OPTI_TYPE_ZERO_BYTE
                                  | OPTI_TYPE_USES_BITS_32
                                  | OPTI_TYPE_RAW_HASH;
static const u64   OPTS_TYPE      = OPTS_TYPE_PT_GENERATE_LE;
static const u32   SALT_TYPE      = SALT_TYPE_EMBEDDED;
static const char *ST_PASS        = "hashcat_hashcat_hashcat_hashcat_";
static const char *ST_HASH        = "$chacha20$*0400000000000003*16*0200000000000001*5152535455565758*6b05fe554b0bc3b3";

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 chacha20
{
  u32 iv[2];
  u32 plain[2];
  u32 position[2];
  u32 offset;

} chacha20_t;

static const char *SIGNATURE_CHACHA20 = "$chacha20$";

const char *module_benchmark_mask (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 char *mask = "?a?a?a?a?a?a?a?axxxxxxxxxxxxxxxxxxxxxxxx";

  return mask;
}

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 (chacha20_t);

  return esalt_size;
}

u32 module_pw_min (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 u32 pw_min = 32; // ChaCha20 fixed

  return pw_min;
}

u32 module_pw_max (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 u32 pw_max = 32; // ChaCha20 fixed

  return pw_max;
}

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;

  chacha20_t *chacha20 = (chacha20_t *) esalt_buf;

  token_t token;

  token.token_cnt  = 6;

  token.signatures_cnt    = 1;
  token.signatures_buf[0] = SIGNATURE_CHACHA20;

  token.sep[0]     = '*';
  token.len_min[0] = 10;
  token.len_max[0] = 10;
  token.attr[0]    = TOKEN_ATTR_VERIFY_LENGTH
                   | TOKEN_ATTR_VERIFY_SIGNATURE;

  token.sep[1]     = '*';
  token.len_min[1] = 16;
  token.len_max[1] = 16;
  token.attr[1]    = TOKEN_ATTR_VERIFY_LENGTH
                   | TOKEN_ATTR_VERIFY_HEX;

  token.sep[2]     = '*';
  token.len_min[2] = 1;
  token.len_max[2] = 2;
  token.attr[2]    = TOKEN_ATTR_VERIFY_LENGTH;

  token.sep[3]     = '*';
  token.len_min[3] = 16;
  token.len_max[3] = 16;
  token.attr[3]    = TOKEN_ATTR_VERIFY_LENGTH
                   | TOKEN_ATTR_VERIFY_HEX;

  token.sep[4]     = '*';
  token.len_min[4] = 16;
  token.len_max[4] = 16;
  token.attr[4]    = TOKEN_ATTR_VERIFY_LENGTH
                   | TOKEN_ATTR_VERIFY_HEX;

  token.sep[5]     = '*';
  token.len_min[5] = 16;
  token.len_max[5] = 16;
  token.attr[5]    = TOKEN_ATTR_VERIFY_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);

  // offset

  const u8 *offset_marker = token.buf[2];

  const int offset = strtol ((const char *) offset_marker, NULL, 10);

  if (offset > 63) return (PARSER_SALT_VALUE);

  chacha20->offset = offset;

  // position

  const u8 *position_marker = token.buf[1];

  chacha20->position[0] = hex_to_u32 ((const u8 *) position_marker + 0);
  chacha20->position[1] = hex_to_u32 ((const u8 *) position_marker + 8);

  // iv

  const u8 *iv_marker = token.buf[3];

  chacha20->iv[0] = hex_to_u32 ((const u8 *) iv_marker + 8);
  chacha20->iv[1] = hex_to_u32 ((const u8 *) iv_marker + 0);

  // plain

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

  chacha20->plain[0] = hex_to_u32 ((const u8 *) plain_marker + 0);
  chacha20->plain[1] = hex_to_u32 ((const u8 *) plain_marker + 8);

  /* some fake salt for the sorting mechanisms */

  salt->salt_buf[0] = chacha20->iv[0];
  salt->salt_buf[1] = chacha20->iv[1];
  salt->salt_buf[2] = chacha20->plain[0];
  salt->salt_buf[3] = chacha20->plain[1];
  salt->salt_buf[4] = chacha20->position[0];
  salt->salt_buf[5] = chacha20->position[1];
  salt->salt_buf[6] = chacha20->offset;
  salt->salt_buf[7] = 0;
  salt->salt_len    = 32;

  /* Store cipher for search mechanism */

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

  digest[0] = hex_to_u32 ((const u8 *) cipher_marker + 8);
  digest[1] = hex_to_u32 ((const u8 *) cipher_marker + 0);

  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 u32 *digest = (const u32 *) digest_buf;

  const chacha20_t *chacha20 = (const chacha20_t *) esalt_buf;

  const int line_len = snprintf (line_buf, line_size, "%s*%08x%08x*%u*%08x%08x*%08x%08x*%08x%08x",
    SIGNATURE_CHACHA20,
    byte_swap_32 (chacha20->position[0]),
    byte_swap_32 (chacha20->position[1]),
    chacha20->offset,
    byte_swap_32 (chacha20->iv[1]),
    byte_swap_32 (chacha20->iv[0]),
    byte_swap_32 (chacha20->plain[0]),
    byte_swap_32 (chacha20->plain[1]),
    byte_swap_32 (digest[1]),
    byte_swap_32 (digest[0]));

  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_benchmark_mask;
  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_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_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_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_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_DEFAULT;
  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_pw_max;
  module_ctx->module_pw_min                   = module_pw_min;
  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;
}
