/*====================================================================* * * void SHA256Fetch (struct sha256 * sha256, uint8_t digest []); * * SHA256.h * * read the SHA256 digest; this function works like function read() * but the function returns no value and the digest buffer is fixed * length; * * to start a digest, use function SHA256Reset(); to write data to * the digest use function SHA256Write(); * * Read standard FIPS180-2 sec 5.3.2 for an explanation; * * Motley Tools by Charles Maier; * Copyright (c) 2001-2006 by Charles Maier Associates; * Licensed under the Internet Software Consortium License; * *--------------------------------------------------------------------*/ #ifndef SHA256FETCH_SOURCE #define SHA256FETCH_SOURCE #include "../key/SHA256.h" static void encode (uint8_t memory [], uint32_t number) { *memory++ = (uint8_t)(number >> 24); *memory++ = (uint8_t)(number >> 16); *memory++ = (uint8_t)(number >> 8); *memory++ = (uint8_t)(number >> 0); return; } void SHA256Fetch (struct sha256 * sha256, uint8_t digest []) { unsigned word; uint8_t bits [8]; uint32_t upper = (sha256->count [0] >> 29) | (sha256->count [1] << 3); uint32_t lower = (sha256->count [0] << 3); uint32_t final = (sha256->count [0] & 0x3F); uint32_t extra = (final < 56)? (56 - final): (120 - final); encode (&bits [0], upper); encode (&bits [4], lower); SHA256Write (sha256, sha256->extra, extra); SHA256Write (sha256, bits, sizeof (bits)); for (word = 0; word < sizeof (sha256->state) / sizeof (uint32_t); word++) { encode (digest, sha256->state [word]); digest += sizeof (uint32_t); } memset (sha256, 0, sizeof (struct sha256)); return; } #endif