| // Copyright 2012 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "polo/util/poloutil.h" |
| |
| #include <openssl/rand.h> |
| |
| namespace polo { |
| namespace util { |
| |
| const std::string PoloUtil::BytesToHexString(const uint8_t* bytes, |
| size_t length) { |
| // Use OpenSSL BigNum functions to perform the conversion. |
| BIGNUM* bn = BN_bin2bn(bytes, length, NULL); |
| char* hex = BN_bn2hex(bn); |
| std::string hex_string(hex); |
| BN_free(bn); |
| OPENSSL_free(hex); |
| return hex_string; |
| } |
| |
| const size_t PoloUtil::HexStringToBytes(const std::string hex_string, |
| uint8_t*& bytes) { |
| // Use OpenSSL BigNum functions to perform the conversion. |
| BIGNUM* bn = NULL; |
| BN_hex2bn(&bn, hex_string.c_str()); |
| int length = BN_num_bytes(bn); |
| bytes = new uint8_t[length]; |
| BN_bn2bin(bn, &bytes[0]); |
| BN_free(bn); |
| return length; |
| } |
| |
| const void PoloUtil::IntToBigEndianBytes(uint32_t value, |
| uint8_t*& bytes) { |
| // Use OpenSSL BigNum functions to perform the conversion. |
| BIGNUM* bn = BN_new(); |
| BN_add_word(bn, value); |
| |
| // Initialize the array to 0 so there will be leading null bytes if the |
| // number is less than 4 bytes long. |
| bytes = new uint8_t[4]; |
| for (int i = 0; i < 4; i++) { |
| bytes[i] = 0; |
| } |
| |
| int length = BN_num_bytes(bn); |
| BN_bn2bin(bn, &bytes[4 - length]); |
| BN_free(bn); |
| } |
| |
| const uint32_t PoloUtil::BigEndianBytesToInt( |
| const uint8_t* bytes) { |
| // Use OpenSSL BigNum functions to perform the conversion. |
| BIGNUM* bn = BN_bin2bn(bytes, 4, NULL); |
| BN_ULONG value = bn->d[0]; |
| BN_free(bn); |
| return value; |
| } |
| |
| uint8_t* PoloUtil::GenerateRandomBytes(size_t length) { |
| // Use the OpenSSL library to generate the random byte array. The RAND_bytes |
| // function is guaranteed to provide secure random bytes. |
| uint8_t* buffer = new uint8_t[length]; |
| if (RAND_bytes(buffer, length)) { |
| return buffer; |
| } else { |
| delete buffer; |
| return NULL; |
| } |
| } |
| |
| } // namespace util |
| } // namespace polo |