| // SPDX-License-Identifier: BSD-2-Clause |
| /* LibTomCrypt, modular cryptographic library -- Tom St Denis |
| * |
| * LibTomCrypt is a library that provides various cryptographic |
| * algorithms in a highly modular and flexible manner. |
| * |
| * The library is free for all purposes without any express |
| * guarantee it works. |
| */ |
| |
| #include "tomcrypt_private.h" |
| |
| /** |
| @file ecc_import.c |
| ECC Crypto, Tom St Denis |
| */ |
| |
| #ifdef LTC_MECC |
| |
| /** |
| Import an ECC key from a binary packet |
| @param in The packet to import |
| @param inlen The length of the packet |
| @param key [out] The destination of the import |
| @return CRYPT_OK if successful, upon error all allocated memory will be freed |
| */ |
| int ecc_import(const unsigned char *in, unsigned long inlen, ecc_key *key) |
| { |
| return ecc_import_ex(in, inlen, key, NULL); |
| } |
| |
| /** |
| Import an ECC key from a binary packet, using user supplied domain params rather than one of the NIST ones |
| @param in The packet to import |
| @param inlen The length of the packet |
| @param key [out] The destination of the import |
| @param cu pointer to user supplied params; must be the same as the params used when exporting |
| @return CRYPT_OK if successful, upon error all allocated memory will be freed |
| */ |
| int ecc_import_ex(const unsigned char *in, unsigned long inlen, ecc_key *key, const ltc_ecc_curve *cu) |
| { |
| unsigned long key_size; |
| unsigned char flags[1]; |
| int err; |
| |
| LTC_ARGCHK(in != NULL); |
| LTC_ARGCHK(key != NULL); |
| LTC_ARGCHK(ltc_mp.name != NULL); |
| |
| /* find out what type of key it is */ |
| err = der_decode_sequence_multi(in, inlen, LTC_ASN1_BIT_STRING, 1UL, flags, |
| LTC_ASN1_SHORT_INTEGER, 1UL, &key_size, |
| LTC_ASN1_EOL, 0UL, NULL); |
| if (err != CRYPT_OK && err != CRYPT_INPUT_TOO_LONG) { |
| return err; |
| } |
| |
| /* allocate & initialize the key */ |
| if (cu == NULL) { |
| if ((err = ecc_set_curve_by_size(key_size, key)) != CRYPT_OK) { goto done; } |
| } else { |
| if ((err = ecc_set_curve(cu, key)) != CRYPT_OK) { goto done; } |
| } |
| |
| if (flags[0] == 1) { |
| /* private key */ |
| key->type = PK_PRIVATE; |
| if ((err = der_decode_sequence_multi(in, inlen, |
| 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)) != CRYPT_OK) { |
| goto done; |
| } |
| } else if (flags[0] == 0) { |
| /* public key */ |
| key->type = PK_PUBLIC; |
| if ((err = der_decode_sequence_multi(in, inlen, |
| 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)) != CRYPT_OK) { |
| goto done; |
| } |
| } |
| else { |
| err = CRYPT_INVALID_PACKET; |
| goto done; |
| } |
| |
| /* set z */ |
| if ((err = mp_set(key->pubkey.z, 1)) != CRYPT_OK) { goto done; } |
| |
| /* point on the curve + other checks */ |
| if ((err = ltc_ecc_verify_key(key)) != CRYPT_OK) { goto done; } |
| |
| /* we're good */ |
| return CRYPT_OK; |
| |
| done: |
| ecc_free(key); |
| return err; |
| } |
| #endif |
| /* ref: $Format:%D$ */ |
| /* git commit: $Format:%H$ */ |
| /* commit time: $Format:%ai$ */ |
| |