Files
data-lite-c/Sources/DataLiteC/libtomcrypt/pk/ecc/ecc_sign_hash_rfc7518.c

74 lines
2.5 KiB
C

/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
#include "tomcrypt_private.h"
#ifdef LTC_MECC
/**
Sign a message digest (RFC7518 format + recovery_id)
@param in The message digest to sign
@param inlen The length of the digest
@param out [out] The destination for the signature
@param outlen [in/out] The max size and resulting size of the signature
@param prng An active PRNG state
@param wprng The index of the PRNG you wish to use
@param recid [out] Recovery ID
@param key A private ECC key
@return CRYPT_OK if successful
*/
int ecc_sign_hash_rfc7518_ex(const unsigned char *in, unsigned long inlen,
unsigned char *out, unsigned long *outlen,
prng_state *prng, int wprng,
int *recid, const ecc_key *key)
{
int err;
void *r, *s;
unsigned long pbytes, i;
LTC_ARGCHK(out != NULL);
LTC_ARGCHK(outlen != NULL);
LTC_ARGCHK(key != NULL);
/* RFC7518 format - raw (r,s) */
pbytes = ltc_mp_unsigned_bin_size(key->dp.order);
if (*outlen < 2 * pbytes) {
*outlen = 2 * pbytes;
return CRYPT_BUFFER_OVERFLOW;
}
if ((err = ltc_mp_init_multi(&r, &s, LTC_NULL)) != CRYPT_OK) return err;
if ((err = ecc_sign_hash_internal(in, inlen, r, s, prng, wprng, recid, key)) != CRYPT_OK) goto error;
zeromem(out, 2 * pbytes);
*outlen = 2 * pbytes;
i = ltc_mp_unsigned_bin_size(r);
if ((err = ltc_mp_to_unsigned_bin(r, out + pbytes - i)) != CRYPT_OK) goto error;
i = ltc_mp_unsigned_bin_size(s);
err = ltc_mp_to_unsigned_bin(s, out + 2 * pbytes - i);
error:
ltc_mp_deinit_multi(r, s, LTC_NULL);
return err;
}
/**
Sign a message digest (RFC7518 format)
@param in The message digest to sign
@param inlen The length of the digest
@param out [out] The destination for the signature
@param outlen [in/out] The max size and resulting size of the signature
@param prng An active PRNG state
@param wprng The index of the PRNG you wish to use
@param key A private ECC key
@return CRYPT_OK if successful
*/
int ecc_sign_hash_rfc7518(const unsigned char *in, unsigned long inlen,
unsigned char *out, unsigned long *outlen,
prng_state *prng, int wprng, const ecc_key *key)
{
return ecc_sign_hash_rfc7518_ex(in, inlen, out, outlen, prng, wprng, NULL, key);
}
#endif