/*====================================================================* * * void SHA256Write (struct sha256 * sha256, void const * memory, size_t extent); * * SHA256.h * * write a block of data to an SHA256 digest; this function behaves * like function write() but returns no value and does not fail; an * unlimited amount of data may be written using successive writes; * * to start a new digest, use function SHA266Reset(); to read the * digest, use function SHA256Fetch(); * * Read standard FIPS180-2 sec 5.3.2 for an explanation; * * Motley Tools by Charles Maier <cmaier@cmassoc.net>; * Copyright (c) 2001-2006 by Charles Maier Associates; * Licensed under the Internet Software Consortium License; * *--------------------------------------------------------------------*/ #ifndef SHA256WRITE_SOURCE #define SHA256WRITE_SOURCE #include "../key/SHA256.h" void SHA256Write (struct sha256 * sha256, void const * memory, size_t extent) { if (extent) { uint8_t * buffer = (uint8_t *)(memory); unsigned left = sha256->count [0] & 0x3F; unsigned fill = sizeof (sha256->block) - left; sha256->count [0] += (uint32_t)(extent); sha256->count [0] &= 0xFFFFFFFF; if (sha256->count [0] < extent) { sha256->count [1]++; } if ((left) && (extent >= fill)) { memcpy (sha256->block + left, buffer, fill); SHA256Block (sha256, sha256->block); extent -= fill; buffer += fill; left = 0; } while (extent >= sizeof (sha256->block)) { SHA256Block (sha256, buffer); extent -= sizeof (sha256->block); buffer += sizeof (sha256->block); } if (extent) { memcpy (sha256->block + left, buffer, extent); } } return; } #endif