62 lines
2.0 KiB
C
62 lines
2.0 KiB
C
/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
|
|
/* SPDX-License-Identifier: Unlicense */
|
|
|
|
#include "tomcrypt_private.h"
|
|
|
|
/**
|
|
@file ecc_export.c
|
|
ECC Crypto, Tom St Denis
|
|
*/
|
|
|
|
#if defined(LTC_MECC) && defined(LTC_DER)
|
|
|
|
/**
|
|
Export an ECC key as a binary packet
|
|
@param out [out] Destination for the key
|
|
@param outlen [in/out] Max size and resulting size of the exported key
|
|
@param type The type of key you want to export (PK_PRIVATE or PK_PUBLIC)
|
|
@param key The key to export
|
|
@return CRYPT_OK if successful
|
|
*/
|
|
int ecc_export(unsigned char *out, unsigned long *outlen, int type, const ecc_key *key)
|
|
{
|
|
int err;
|
|
unsigned char flags[1];
|
|
unsigned long key_size;
|
|
|
|
LTC_ARGCHK(out != NULL);
|
|
LTC_ARGCHK(outlen != NULL);
|
|
LTC_ARGCHK(key != NULL);
|
|
|
|
/* type valid? */
|
|
if (key->type != PK_PRIVATE && type == PK_PRIVATE) {
|
|
return CRYPT_PK_TYPE_MISMATCH;
|
|
}
|
|
|
|
/* we store the NIST byte size */
|
|
key_size = key->dp.size;
|
|
|
|
if (type == PK_PRIVATE) {
|
|
flags[0] = 1;
|
|
err = der_encode_sequence_multi(out, outlen,
|
|
LTC_ASN1_BIT_STRING, 1UL, flags,
|
|
LTC_ASN1_SHORT_INTEGER, 1UL, &key_size,
|
|
LTC_ASN1_INTEGER, 1UL, key->pubkey.x,
|
|
LTC_ASN1_INTEGER, 1UL, key->pubkey.y,
|
|
LTC_ASN1_INTEGER, 1UL, key->k,
|
|
LTC_ASN1_EOL, 0UL, NULL);
|
|
} else {
|
|
flags[0] = 0;
|
|
err = der_encode_sequence_multi(out, outlen,
|
|
LTC_ASN1_BIT_STRING, 1UL, flags,
|
|
LTC_ASN1_SHORT_INTEGER, 1UL, &key_size,
|
|
LTC_ASN1_INTEGER, 1UL, key->pubkey.x,
|
|
LTC_ASN1_INTEGER, 1UL, key->pubkey.y,
|
|
LTC_ASN1_EOL, 0UL, NULL);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
#endif
|