| // 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 pkcs_1_i2osp.c |
| Integer to Octet I2OSP, Tom St Denis |
| */ |
| |
| #ifdef LTC_PKCS_1 |
| |
| /* always stores the same # of bytes, pads with leading zero bytes |
| as required |
| */ |
| |
| /** |
| PKCS #1 Integer to binary |
| @param n The integer to store |
| @param modulus_len The length of the RSA modulus |
| @param out [out] The destination for the integer |
| @return CRYPT_OK if successful |
| */ |
| int pkcs_1_i2osp(void *n, unsigned long modulus_len, unsigned char *out) |
| { |
| unsigned long size; |
| |
| size = mp_unsigned_bin_size(n); |
| |
| if (size > modulus_len) { |
| return CRYPT_BUFFER_OVERFLOW; |
| } |
| |
| /* store it */ |
| zeromem(out, modulus_len); |
| return mp_to_unsigned_bin(n, out+(modulus_len-size)); |
| } |
| |
| #endif /* LTC_PKCS_1 */ |
| |
| |
| /* ref: $Format:%D$ */ |
| /* git commit: $Format:%H$ */ |
| /* commit time: $Format:%ai$ */ |