Function SHA256_Update

freebsd/crypto/sha2/sha256c.c:247–284

Add bytes into the hash */

/* Add bytes into the hash */
void
SHA256_Update(SHA256_CTX * ctx, const void *in, size_t len)
{
	uint64_t bitlen;
	uint32_t r;
	const unsigned char *src = in;

	/* Number of bytes left in the buffer from previous updates */
	r = (ctx->count >> 3) & 0x3f;

	/* Convert the length into a number of bits */
	bitlen = len << 3;

	/* Update number of bits */
	ctx->count += bitlen;

	/* Handle the case where we don't need to perform any transforms */
	if (len < 64 - r) {
		memcpy(&ctx->buf[r], src, len);
		return;
	}

	/* Finish the current block */
	memcpy(&ctx->buf[r], src, 64 - r);
	SHA256_Transform(ctx->state, ctx->buf);
	src += 64 - r;
	len -= 64 - r;

	/* Perform complete blocks */
	while (len >= 64) {
		SHA256_Transform(ctx->state, src);
		src += 64;
		len -= 64;
	}

	/* Copy left over data into buffer */
	memcpy(ctx->buf, src, len);
}

/*
 * SHA-256 finalization.  Pads the input data, exports the hash value,