wsutil/wsgcrypt.h

   1 /** @file
   2  *
   3  * Wrapper around libgcrypt's include file gcrypt.h.
   4  * For libgcrypt 1.5.0, including gcrypt.h directly brings up lots of
   5  * compiler warnings about deprecated definitions.
   6  * Try to work around these warnings to ensure a clean build with -Werror.
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 2007 Gerald Combs
  11  *
  12  * SPDX-License-Identifier: GPL-2.0-or-later
  13  */
  14
  15 #ifndef __WSGCRYPT_H__
  16 #define __WSGCRYPT_H__
  17
  18 #include <wireshark.h>
  19 #include <gcrypt.h>
  20
  21 #define HASH_MD5_LENGTH      16
  22 #define HASH_SHA1_LENGTH     20
  23 #define HASH_SHA2_224_LENGTH 28
  24 #define HASH_SHA2_256_LENGTH 32
  25 #define HASH_SHA2_384_LENGTH 48
  26 #define HASH_SHA2_512_LENGTH 64
  27
  28 /* Convenience function to calculate the HMAC from the data in BUFFER
  29    of size LENGTH with key KEY of size KEYLEN using the algorithm ALGO avoiding the creating of a
  30    hash object. The hash is returned in the caller provided buffer
  31    DIGEST which must be large enough to hold the digest of the given
  32    algorithm. */
  33 WS_DLL_PUBLIC gcry_error_t ws_hmac_buffer(int algo, void *digest, const void *buffer, size_t length, const void *key, size_t keylen);
  34
  35 WS_DLL_PUBLIC gcry_error_t ws_cmac_buffer(int algo, void *digest, const void *buffer, size_t length, const void *key, size_t keylen);
  36
  37 /* Convenience function to encrypt 8 bytes in BUFFER with DES using the 56 bits KEY expanded to
  38    64 bits as key, encrypted data is returned in OUTPUT which must be at least 8 bytes large */
  39 WS_DLL_PUBLIC void crypt_des_ecb(uint8_t *output, const uint8_t *buffer, const uint8_t *key56);
  40 WS_DLL_PUBLIC void decrypt_des_ecb(uint8_t *output, const uint8_t *buffer, const uint8_t *key56);
  41
  42 /* Convenience function for RSA decryption. Returns decrypted length on success, 0 on failure */
  43 WS_DLL_PUBLIC size_t rsa_decrypt_inplace(const unsigned len, unsigned char* data, gcry_sexp_t pk, bool pkcs1_padding, char **err);
  44
  45 /**
  46  * RFC 5869 HMAC-based Extract-and-Expand Key Derivation Function (HKDF):
  47  * HKDF-Expand(PRK, info, L) -> OKM
  48  *
  49  * @param hashalgo  [in] Libgcrypt hash algorithm identifier.
  50  * @param prk       [in] Pseudo-random key.
  51  * @param prk_len   [in] Length of prk.
  52  * @param info      [in] Optional context (can be NULL if info_len is zero).
  53  * @param info_len  [in] Length of info.
  54  * @param out       [out] Output keying material.
  55  * @param out_len   [in] Size of output keying material.
  56  * @return 0 on success and an error code otherwise.
  57  */
  58 WS_DLL_PUBLIC gcry_error_t
  59 hkdf_expand(int hashalgo, const uint8_t *prk, unsigned prk_len, const uint8_t *info, unsigned info_len,
  60             uint8_t *out, unsigned out_len);
  61
  62 /*
  63  * Calculate HKDF-Extract(salt, IKM) -> PRK according to RFC 5869.
  64  * Caller MUST ensure that 'prk' is large enough to store the digest from hash
  65  * algorithm 'hashalgo' (e.g. 32 bytes for SHA-256).
  66  */
  67 static inline gcry_error_t
  68 hkdf_extract(int hashalgo, const uint8_t *salt, size_t salt_len, const uint8_t *ikm, size_t ikm_len, uint8_t *prk)
  69 {
  70     /* PRK = HMAC-Hash(salt, IKM) where salt is key, and IKM is input. */
  71     return ws_hmac_buffer(hashalgo, prk, ikm, ikm_len, salt, salt_len);
  72 }
  73
  74
  75 #endif /* __WSGCRYPT_H__ */