libblake_internal_blake2b_output_digest.c


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/* See LICENSE file for copyright and license details. */
#include "common.h"

static void
encode_uint64_le(unsigned char *out, uint_least64_t value, size_t bytes)
{
	switch (bytes) {
	default:
		out[7] = (unsigned char)((value >> 56) & 255);
		/* fall through */
	case 7:
		out[6] = (unsigned char)((value >> 48) & 255);
		/* fall through */
	case 6:
		out[5] = (unsigned char)((value >> 40) & 255);
		/* fall through */
	case 5:
		out[4] = (unsigned char)((value >> 32) & 255);
		/* fall through */
	case 4:
		out[3] = (unsigned char)((value >> 24) & 255);
		/* fall through */
	case 3:
		out[2] = (unsigned char)((value >> 16) & 255);
		/* fall through */
	case 2:
		out[1] = (unsigned char)((value >>  8) & 255);
		/* fall through */
	case 1:
		out[0] = (unsigned char)((value >>  0) & 255);
		/* fall through */
	case 0:
		break;
	}
}

void
libblake_internal_blake2b_output_digest(struct libblake_blake2b_state *state, size_t output_len, unsigned char *output)
{
	size_t i, j;

	for (i = 0, j = 0; i < output_len; i += 8, j += 1)
		encode_uint64_le(&output[i], state->h[j], output_len - i);
}