/* finalize the hash computation and output the block, no OUTPUT stage */
int Skein_512_Final_Pad(Skein_512_Ctxt_t *ctx, u08b_t *hashVal)
{
Skein_Assert(ctx->h.bCnt <= SKEIN_512_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
ctx->h.T[1] |= SKEIN_T1_FLAG_FINAL; /* tag as the final block */
if (ctx->h.bCnt < SKEIN_512_BLOCK_BYTES) /* zero pad b[] if necessary */
memset(&ctx->b[ctx->h.bCnt],0,SKEIN_512_BLOCK_BYTES - ctx->h.bCnt);
Skein_512_Process_Block(ctx,ctx->b,1,ctx->h.bCnt); /* process the final block */
Skein_Put64_LSB_First(hashVal,ctx->X,SKEIN_512_BLOCK_BYTES); /* "output" the state bytes */
return SKEIN_SUCCESS;
}
/* finalize the hash computation and output the result */
int
Skein1024_Final(Skein1024_Ctxt_t *ctx, uint8_t *hashVal)
{
size_t i, n, byteCnt;
uint64_t X[SKEIN1024_STATE_WORDS];
/* catch uninitialized context */
Skein_Assert(ctx->h.bCnt <= SKEIN1024_BLOCK_BYTES, SKEIN_FAIL);
ctx->h.T[1] |= SKEIN_T1_FLAG_FINAL; /* tag as the final block */
/* zero pad b[] if necessary */
if (ctx->h.bCnt < SKEIN1024_BLOCK_BYTES)
bzero(&ctx->b[ctx->h.bCnt],
SKEIN1024_BLOCK_BYTES - ctx->h.bCnt);
/* process the final block */
Skein1024_Process_Block(ctx, ctx->b, 1, ctx->h.bCnt);
/* now output the result */
/* total number of output bytes */
byteCnt = (ctx->h.hashBitLen + 7) >> 3;
/* run Threefish in "counter mode" to generate output */
/* zero out b[], so it can hold the counter */
bzero(ctx->b, sizeof (ctx->b));
/* keep a local copy of counter mode "key" */
bcopy(ctx->X, X, sizeof (X));
for (i = 0; i * SKEIN1024_BLOCK_BYTES < byteCnt; i++) {
/* build the counter block */
uint64_t tmp = Skein_Swap64((uint64_t)i);
bcopy(&tmp, ctx->b, sizeof (tmp));
Skein_Start_New_Type(ctx, OUT_FINAL);
/* run "counter mode" */
Skein1024_Process_Block(ctx, ctx->b, 1, sizeof (uint64_t));
/* number of output bytes left to go */
n = byteCnt - i * SKEIN1024_BLOCK_BYTES;
if (n >= SKEIN1024_BLOCK_BYTES)
n = SKEIN1024_BLOCK_BYTES;
Skein_Put64_LSB_First(hashVal + i * SKEIN1024_BLOCK_BYTES,
ctx->X, n); /* "output" the ctr mode bytes */
Skein_Show_Final(1024, &ctx->h, n,
hashVal + i * SKEIN1024_BLOCK_BYTES);
/* restore the counter mode key for next time */
bcopy(X, ctx->X, sizeof (X));
}
return (SKEIN_SUCCESS);
}
/* finalize the hash computation and output the block, no OUTPUT stage */
int
Skein_256_Final_Pad(Skein_256_Ctxt_t *ctx, uint8_t *hashVal)
{
/* catch uninitialized context */
Skein_Assert(ctx->h.bCnt <= SKEIN_256_BLOCK_BYTES, SKEIN_FAIL);
ctx->h.T[1] |= SKEIN_T1_FLAG_FINAL; /* tag as the final block */
/* zero pad b[] if necessary */
if (ctx->h.bCnt < SKEIN_256_BLOCK_BYTES)
bzero(&ctx->b[ctx->h.bCnt],
SKEIN_256_BLOCK_BYTES - ctx->h.bCnt);
/* process the final block */
Skein_256_Process_Block(ctx, ctx->b, 1, ctx->h.bCnt);
/* "output" the state bytes */
Skein_Put64_LSB_First(hashVal, ctx->X, SKEIN_256_BLOCK_BYTES);
return (SKEIN_SUCCESS);
}