1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071 |
- /*
- * ZMap Copyright 2013 Regents of the University of Michigan
- *
- * 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
- */
- #include <stdlib.h>
- #include <stdint.h>
- #include <assert.h>
- #include <string.h>
- #include "rijndael-alg-fst.h"
- #include "random.h"
- #include "logger.h"
- #include "xalloc.h"
- #include "aesrand.h"
- #define AES_ROUNDS 10
- #define AES_BLOCK_WORDS 4
- #define AES_KEY_BYTES 16
- #define AES_KEY_BITS (AES_KEY_BYTES*8)
- #define OUTPUT_BYTES 16
- struct aesrand {
- uint32_t input[AES_BLOCK_WORDS];
- uint32_t sched[(AES_ROUNDS+1)*4];
- uint8_t output[OUTPUT_BYTES];
- };
- static aesrand_t* _aesrand_init(uint8_t *key)
- {
- aesrand_t *aes = xmalloc(sizeof(aesrand_t));
- memset(&aes->input, 0, AES_BLOCK_WORDS*4);
- if (rijndaelKeySetupEnc(aes->sched, key, AES_KEY_BITS) != AES_ROUNDS) {
- log_fatal("aesrand", "could not initialize AES key");
- }
- memset(aes->output, 0, OUTPUT_BYTES);
- return aes;
- }
- aesrand_t* aesrand_init_from_seed(uint64_t seed)
- {
- uint8_t key[AES_KEY_BYTES];
- memset(key, 0, AES_KEY_BYTES);
- for (uint8_t i = 0; i < sizeof(seed); ++i) {
- key[i] = (uint8_t) ((seed >> 8*i) & 0xFF);
- }
- return _aesrand_init(key);
- }
- aesrand_t* aesrand_init_from_random()
- {
- uint8_t key[AES_KEY_BYTES];
- if (!random_bytes(key, AES_KEY_BYTES)) {
- log_fatal("aesrand", "Couldn't get random bytes");
- }
- return _aesrand_init(key);
- }
- uint64_t aesrand_getword(aesrand_t *aes)
- {
- memcpy(aes->input, aes->output, sizeof(aes->input));
- rijndaelEncrypt(aes->sched, AES_ROUNDS,
- (uint8_t *)aes->input, aes->output);
- uint64_t retval;
- memcpy(&retval, aes->output, sizeof(retval));
- return retval;
- }
|