28 lines
727 B
C
28 lines
727 B
C
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/* Hardware Random Number Generator Functions
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*
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* For documentation, see http://esp8266-re.foogod.com/wiki/Random_Number_Generator
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*
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* Part of esp-open-rtos
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* Copyright (C) 2015 Angus Gratton
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* BSD Licensed as described in the file LICENSE
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*/
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#include <esp/hwrand.h>
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#include <esp/wdev_regs.h>
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#include <string.h>
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/* Return a random 32-bit number */
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uint32_t hwrand(void)
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{
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return WDEV.HWRNG;
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}
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/* Fill a variable size buffer with data from the Hardware RNG */
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void hwrand_fill(uint8_t *buf, size_t len)
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{
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for(size_t i = 0; i < len; i+=4) {
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uint32_t random = WDEV.HWRNG;
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/* using memcpy here in case 'buf' is unaligned */
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memcpy(buf + i, &random, (i+4 <= len) ? 4 : (len % 4));
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}
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}
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