// SPDX-License-Identifier: LGPL-2.1-or-later

/*

 * Argon2 PBKDF2 library wrapper

 *

 * Copyright (C) 2016-2025 Red Hat, Inc. All rights reserved.

 * Copyright (C) 2016-2025 Milan Broz

 */

#include <errno.h>

#include "crypto_backend_internal.h"

/* Check for HAVE_ARGON2_H is run only if libargon2 code is used */

#if USE_INTERNAL_ARGON2 || HAVE_ARGON2_H

#define CONST_CAST(x) (x)(uintptr_t)

#if HAVE_ARGON2_H

#include <argon2.h>

#else

#include "argon2/argon2.h"

#endif

int argon2(const char *type, const char *password, size_t password_length,

     const char *salt, size_t salt_length,

     char *key, size_t key_length,

     uint32_t iterations, uint32_t memory, uint32_t parallel)

{

  argon2_type atype;

  argon2_context context = {

    .flags = ARGON2_DEFAULT_FLAGS,

    .version = ARGON2_VERSION_NUMBER,

    .t_cost = (uint32_t)iterations,

    .m_cost = (uint32_t)memory,

    .lanes = (uint32_t)parallel,

    .threads = (uint32_t)parallel,

    .out = (uint8_t *)key,

    .outlen = (uint32_t)key_length,

    .pwd = CONST_CAST(uint8_t *)password,

    .pwdlen = (uint32_t)password_length,

    .salt = CONST_CAST(uint8_t *)salt,

    .saltlen = (uint32_t)salt_length,

  };

  int r;

  /* This code must not be run if crypt backend library natively supports Argon2 */

  assert(!(crypt_backend_flags() & CRYPT_BACKEND_ARGON2));

  if (!strcmp(type, "argon2i"))

    atype = Argon2_i;

  else if(!strcmp(type, "argon2id"))

    atype = Argon2_id;

  else

    return -EINVAL;

  switch (argon2_ctx(&context, atype)) {

  case ARGON2_OK:

    r = 0;

    break;

  case ARGON2_MEMORY_ALLOCATION_ERROR:

  case ARGON2_FREE_MEMORY_CBK_NULL:

  case ARGON2_ALLOCATE_MEMORY_CBK_NULL:

    r = -ENOMEM;

    break;

  default:

    r = -EINVAL;

  }

  return r;

}

#else /* USE_INTERNAL_ARGON2 || HAVE_ARGON2_H */

#pragma GCC diagnostic ignored "-Wunused-parameter"

int argon2(const char *type, const char *password, size_t password_length,

     const char *salt, size_t salt_length,

     char *key, size_t key_length,

     uint32_t iterations, uint32_t memory, uint32_t parallel)

{

  return -EINVAL;

}

#endif

/* Additional string for crypt backend version */

const char *crypt_argon2_version(void)

{

  const char *version = "";

  if (crypt_backend_flags() & CRYPT_BACKEND_ARGON2)

    return version;

#if HAVE_ARGON2_H /* this has priority over internal argon2 */

  version = " [external libargon2]";

#elif USE_INTERNAL_ARGON2

  version = " [cryptsetup libargon2]";

#endif

  return version;

}