1/* 2 * prng.h 3 * 4 * pseudorandom source 5 * 6 * David A. McGrew 7 * Cisco Systems, Inc. 8 */ 9 10#ifndef PRNG_H 11#define PRNG_H 12 13#include "rand_source.h" /* for rand_source_func_t definition */ 14#include "aes.h" /* for aes */ 15#include "aes_icm.h" /* for aes ctr */ 16 17#define MAX_PRNG_OUT_LEN 0xffffffffU 18 19/* 20 * x917_prng is an ANSI X9.17-like AES-based PRNG 21 */ 22 23typedef struct { 24 v128_t state; /* state data */ 25 aes_expanded_key_t key; /* secret key */ 26 uint32_t octet_count; /* number of octets output since last init */ 27 rand_source_func_t rand; /* random source for re-initialization */ 28} x917_prng_t; 29 30err_status_t 31x917_prng_init(rand_source_func_t random_source); 32 33err_status_t 34x917_prng_get_octet_string(uint8_t *dest, uint32_t len); 35 36 37/* 38 * ctr_prng is an AES-CTR based PRNG 39 */ 40 41typedef struct { 42 uint32_t octet_count; /* number of octets output since last init */ 43 aes_icm_ctx_t state; /* state data */ 44 rand_source_func_t rand; /* random source for re-initialization */ 45} ctr_prng_t; 46 47err_status_t 48ctr_prng_init(rand_source_func_t random_source); 49 50err_status_t 51ctr_prng_get_octet_string(void *dest, uint32_t len); 52 53 54#endif 55