void skein512_update(struct skein512_ctx *ctx, uint8_t *data, uint32_t len)
{
uint32_t to_fill;
to_fill = 64 - ctx->bufindex;
if (ctx->bufindex == 64) {
skein512_do_chunk(ctx, (uint64_t *) ctx->buf, 64);
ctx->bufindex = 0;
}
/* process partial buffer if there's enough data to make a block */
if (ctx->bufindex && len >= to_fill) {
memcpy(ctx->buf + ctx->bufindex, data, to_fill);
skein512_do_chunk(ctx, (uint64_t *) ctx->buf, 64);
len -= to_fill;
data += to_fill;
ctx->bufindex = 0;
}
/* process as much 64-block as possible except the last one in case we finalize */
for (; len > 64; len -= 64, data += 64)
skein512_do_chunk(ctx, (uint64_t *) data, 64);
/* append data into buf */
if (len) {
memcpy(ctx->buf + ctx->bufindex, data, len);
ctx->bufindex += len;
}
}
void cryptonite_skein512_update(struct skein512_ctx *ctx, const uint8_t *data, uint32_t len)
{
uint32_t to_fill;
if (!len)
return;
to_fill = 64 - ctx->bufindex;
if (ctx->bufindex == 64) {
skein512_do_chunk(ctx, (uint64_t *) ctx->buf, 64);
ctx->bufindex = 0;
}
/* process partial buffer if there's enough data to make a block
* and there's without doubt further blocks */
if (ctx->bufindex && len > to_fill) {
memcpy(ctx->buf + ctx->bufindex, data, to_fill);
skein512_do_chunk(ctx, (uint64_t *) ctx->buf, 64);
len -= to_fill;
data += to_fill;
ctx->bufindex = 0;
}
if (need_alignment(data, 8)) {
uint64_t tramp[8];
ASSERT_ALIGNMENT(tramp, 8);
for (; len > 64; len -= 64, data += 64) {
memcpy(tramp, data, 64);
skein512_do_chunk(ctx, tramp, 64);
}
} else {
/* process as much 64-block as possible except the last one in case we finalize */
for (; len > 64; len -= 64, data += 64)
skein512_do_chunk(ctx, (uint64_t *) data, 64);
}
/* append data into buf */
if (len) {
memcpy(ctx->buf + ctx->bufindex, data, len);
ctx->bufindex += len;
}
}
void skein512_finalize(struct skein512_ctx *ctx, uint8_t *out)
{
uint32_t outsize;
uint64_t *p = (uint64_t *) out;
uint64_t x[8];
int i, j, n;
ctx->t1 |= FLAG_FINAL;
/* if buf is not complete pad with 0 bytes */
if (ctx->bufindex < 64)
memset(ctx->buf + ctx->bufindex, '\0', 64 - ctx->bufindex);
skein512_do_chunk(ctx, (uint64_t *) ctx->buf, ctx->bufindex);
memset(ctx->buf, '\0', 64);
/* make sure we have a 8 bit rounded value */
outsize = ctx->hashlen;
/* backup h[0--7] */
for (j = 0; j < 8; j++)
x[j] = ctx->h[j];
/* threefish in counter mode, 0 for 1st 64 bytes, 1 for 2nd 64 bytes, .. */
for (i = 0; i*64 < outsize; i++) {
uint64_t w[8];
*((uint64_t *) ctx->buf) = cpu_to_le64(i);
SET_TYPE(ctx, FLAG_FIRST | FLAG_FINAL | FLAG_TYPE(TYPE_OUT));
skein512_do_chunk(ctx, (uint64_t *) ctx->buf, sizeof(uint64_t));
n = outsize - i * 64;
if (n >= 64) n = 64;
cpu_to_le64_array(w, ctx->h, 8);
memcpy(out + i*64, w, n);
/* restore h[0--7] */
for (j = 0; j < 8; j++)
ctx->h[j] = x[j];
}
}
void cryptonite_skein512_init(struct skein512_ctx *ctx, uint32_t hashlen)
{
uint64_t buf[8];
memset(ctx, 0, sizeof(*ctx));
SET_TYPE(ctx, FLAG_FIRST | FLAG_FINAL | FLAG_TYPE(TYPE_CFG));
memset(buf, '\0', sizeof(buf));
buf[0] = cpu_to_le64((SKEIN_VERSION << 32) | SKEIN_IDSTRING);
buf[1] = cpu_to_le64(hashlen);
buf[2] = 0; /* tree info, not implemented */
skein512_do_chunk(ctx, buf, 4*8);
SET_TYPE(ctx, FLAG_FIRST | FLAG_TYPE(TYPE_MSG));
}
