| /* Copyright (c) 2015, Google Inc. |
| * |
| * Permission to use, copy, modify, and/or distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION |
| * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ |
| |
| #include <openssl/bn.h> |
| |
| #include <openssl/bytestring.h> |
| #include <openssl/err.h> |
| |
| |
| int BN_parse_asn1_unsigned(CBS *cbs, BIGNUM *ret) { |
| CBS child; |
| if (!CBS_get_asn1(cbs, &child, CBS_ASN1_INTEGER) || |
| CBS_len(&child) == 0) { |
| OPENSSL_PUT_ERROR(BN, BN_R_BAD_ENCODING); |
| return 0; |
| } |
| |
| if (CBS_data(&child)[0] & 0x80) { |
| OPENSSL_PUT_ERROR(BN, BN_R_NEGATIVE_NUMBER); |
| return 0; |
| } |
| |
| // INTEGERs must be minimal. |
| if (CBS_data(&child)[0] == 0x00 && |
| CBS_len(&child) > 1 && |
| !(CBS_data(&child)[1] & 0x80)) { |
| OPENSSL_PUT_ERROR(BN, BN_R_BAD_ENCODING); |
| return 0; |
| } |
| |
| return BN_bin2bn(CBS_data(&child), CBS_len(&child), ret) != NULL; |
| } |
| |
| int BN_parse_asn1_unsigned_buggy(CBS *cbs, BIGNUM *ret) { |
| CBS child; |
| if (!CBS_get_asn1(cbs, &child, CBS_ASN1_INTEGER) || |
| CBS_len(&child) == 0) { |
| OPENSSL_PUT_ERROR(BN, BN_R_BAD_ENCODING); |
| return 0; |
| } |
| |
| // This function intentionally does not reject negative numbers or non-minimal |
| // encodings. Estonian IDs issued between September 2014 to September 2015 are |
| // broken. See https://crbug.com/532048 and https://crbug.com/534766. |
| // |
| // TODO(davidben): Remove this code and callers in March 2016. |
| return BN_bin2bn(CBS_data(&child), CBS_len(&child), ret) != NULL; |
| } |
| |
| int BN_marshal_asn1(CBB *cbb, const BIGNUM *bn) { |
| // Negative numbers are unsupported. |
| if (BN_is_negative(bn)) { |
| OPENSSL_PUT_ERROR(BN, BN_R_NEGATIVE_NUMBER); |
| return 0; |
| } |
| |
| CBB child; |
| if (!CBB_add_asn1(cbb, &child, CBS_ASN1_INTEGER) || |
| // The number must be padded with a leading zero if the high bit would |
| // otherwise be set or if |bn| is zero. |
| (BN_num_bits(bn) % 8 == 0 && !CBB_add_u8(&child, 0x00)) || |
| !BN_bn2cbb_padded(&child, BN_num_bytes(bn), bn) || |
| !CBB_flush(cbb)) { |
| OPENSSL_PUT_ERROR(BN, BN_R_ENCODE_ERROR); |
| return 0; |
| } |
| |
| return 1; |
| } |