src/lib/crypt_ops/crypto_s2k.h

   1 /* Copyright (c) 2001, Matej Pfajfar.
   2  * Copyright (c) 2001-2004, Roger Dingledine.
   3  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   4  * Copyright (c) 2007-2021, The Tor Project, Inc. */
   5 /* See LICENSE for licensing information */
   6
   7 /**
   8  * \file crypto_s2k.h
   9  *
  10  * \brief Header for crypto_s2k.c
  11  **/
  12
  13 #ifndef TOR_CRYPTO_S2K_H_INCLUDED
  14 #define TOR_CRYPTO_S2K_H_INCLUDED
  15
  16 #include <stdio.h>
  17 #include "lib/cc/torint.h"
  18
  19 /** Length of RFC2440-style S2K specifier: the first 8 bytes are a salt, the
  20  * 9th describes how much iteration to do. */
  21 #define S2K_RFC2440_SPECIFIER_LEN 9
  22 void secret_to_key_rfc2440(
  23                    char *key_out, size_t key_out_len, const char *secret,
  24                    size_t secret_len, const char *s2k_specifier);
  25
  26 /** Flag for secret-to-key function: do not use scrypt. */
  27 #define S2K_FLAG_NO_SCRYPT  (1u<<0)
  28 /** Flag for secret-to-key functions: if using a memory-tuned s2k function,
  29  * assume that we have limited memory. */
  30 #define S2K_FLAG_LOW_MEM    (1u<<1)
  31 /** Flag for secret-to-key functions: force use of pbkdf2.  Without this, we
  32  * default to scrypt, then RFC2440. */
  33 #define S2K_FLAG_USE_PBKDF2 (1u<<2)
  34
  35 /** Maximum possible output length from secret_to_key_new. */
  36 #define S2K_MAXLEN 64
  37
  38 /** Error code from secret-to-key functions: all is well */
  39 #define S2K_OKAY 0
  40 /** Error code from secret-to-key functions: generic failure */
  41 #define S2K_FAILED -1
  42 /** Error code from secret-to-key functions: provided secret didn't match */
  43 #define S2K_BAD_SECRET -2
  44 /** Error code from secret-to-key functions: didn't recognize the algorithm */
  45 #define S2K_BAD_ALGORITHM -3
  46 /** Error code from secret-to-key functions: specifier wasn't valid */
  47 #define S2K_BAD_PARAMS -4
  48 /** Error code from secret-to-key functions: compiled without scrypt */
  49 #define S2K_NO_SCRYPT_SUPPORT -5
  50 /** Error code from secret-to-key functions: not enough space to write output.
  51  */
  52 #define S2K_TRUNCATED -6
  53 /** Error code from secret-to-key functions: Wrong length for specifier. */
  54 #define S2K_BAD_LEN -7
  55
  56 int secret_to_key_new(uint8_t *buf,
  57                       size_t buf_len,
  58                       size_t *len_out,
  59                       const char *secret, size_t secret_len,
  60                       unsigned flags);
  61
  62 int secret_to_key_make_specifier(uint8_t *buf, size_t buf_len, unsigned flags);
  63
  64 int secret_to_key_check(const uint8_t *spec_and_key, size_t spec_and_key_len,
  65                           const char *secret, size_t secret_len);
  66
  67 int secret_to_key_derivekey(uint8_t *key_out, size_t key_out_len,
  68                             const uint8_t *spec, size_t spec_len,
  69                             const char *secret, size_t secret_len);
  70
  71 #ifdef CRYPTO_S2K_PRIVATE
  72 STATIC int secret_to_key_compute_key(uint8_t *key_out, size_t key_out_len,
  73                                      const uint8_t *spec, size_t spec_len,
  74                                      const char *secret, size_t secret_len,
  75                                      int type);
  76 #endif /* defined(CRYPTO_S2K_PRIVATE) */
  77
  78 #endif /* !defined(TOR_CRYPTO_S2K_H_INCLUDED) */