/* init the context for a straight hashing operation */
int
Skein_512_Init(Skein_512_Ctxt_t *ctx, size_t hashBitLen)
{
union {
uint8_t b[SKEIN_512_STATE_BYTES];
uint64_t w[SKEIN_512_STATE_WORDS];
} cfg; /* config block */
Skein_Assert(hashBitLen > 0, SKEIN_BAD_HASHLEN);
ctx->h.hashBitLen = hashBitLen; /* output hash bit count */
switch (hashBitLen) { /* use pre-computed values, where available */
#ifndef SKEIN_NO_PRECOMP
case 512:
bcopy(SKEIN_512_IV_512, ctx->X, sizeof (ctx->X));
break;
case 384:
bcopy(SKEIN_512_IV_384, ctx->X, sizeof (ctx->X));
break;
case 256:
bcopy(SKEIN_512_IV_256, ctx->X, sizeof (ctx->X));
break;
case 224:
bcopy(SKEIN_512_IV_224, ctx->X, sizeof (ctx->X));
break;
#endif
default:
/*
* here if there is no precomputed IV value available
* build/process the config block, type == CONFIG (could be
* precomputed)
*/
/* set tweaks: T0=0; T1=CFG | FINAL */
Skein_Start_New_Type(ctx, CFG_FINAL);
/* set the schema, version */
cfg.w[0] = Skein_Swap64(SKEIN_SCHEMA_VER);
/* hash result length in bits */
cfg.w[1] = Skein_Swap64(hashBitLen);
cfg.w[2] = Skein_Swap64(SKEIN_CFG_TREE_INFO_SEQUENTIAL);
/* zero pad config block */
bzero(&cfg.w[3], sizeof (cfg) - 3 * sizeof (cfg.w[0]));
/* compute the initial chaining values from config block */
/* zero the chaining variables */
bzero(ctx->X, sizeof (ctx->X));
Skein_512_Process_Block(ctx, cfg.b, 1, SKEIN_CFG_STR_LEN);
break;
}
/*
* The chaining vars ctx->X are now initialized for the given
* hashBitLen. Set up to process the data message portion of the
* hash (default)
*/
Skein_Start_New_Type(ctx, MSG); /* T0=0, T1= MSG type */
return (SKEIN_SUCCESS);
}
/* [identical to Skein_512_Init() when keyBytes == 0 && treeInfo == SKEIN_CFG_TREE_INFO_SEQUENTIAL] */
int Skein_512_InitExt(Skein_512_Ctxt_t *ctx,size_t hashBitLen,u64b_t treeInfo, const u08b_t *key, size_t keyBytes)
{
union
{
u08b_t b[SKEIN_512_STATE_BYTES];
u64b_t w[SKEIN_512_STATE_WORDS];
} cfg; /* config block */
Skein_Assert(hashBitLen > 0,SKEIN_BAD_HASHLEN);
Skein_Assert(keyBytes == 0 || key != NULL,SKEIN_FAIL);
/* compute the initial chaining values ctx->X[], based on key */
if (keyBytes == 0) /* is there a key? */
{
memset(ctx->X,0,sizeof(ctx->X)); /* no key: use all zeroes as key for config block */
}
else /* here to pre-process a key */
{
Skein_assert(sizeof(cfg.b) >= sizeof(ctx->X));
/* do a mini-Init right here */
ctx->h.hashBitLen=8*sizeof(ctx->X); /* set output hash bit count = state size */
Skein_Start_New_Type(ctx,KEY); /* set tweaks: T0 = 0; T1 = KEY type */
memset(ctx->X,0,sizeof(ctx->X)); /* zero the initial chaining variables */
Skein_512_Update(ctx,key,keyBytes); /* hash the key */
Skein_512_Final_Pad(ctx,cfg.b); /* put result into cfg.b[] */
memcpy(ctx->X,cfg.b,sizeof(cfg.b)); /* copy over into ctx->X[] */
#if SKEIN_NEED_SWAP
{
uint_t i;
for (i=0; i<SKEIN_512_STATE_WORDS; i++) /* convert key bytes to context words */
ctx->X[i] = Skein_Swap64(ctx->X[i]);
}
#endif
}
/* build/process the config block, type == CONFIG (could be precomputed for each key) */
ctx->h.hashBitLen = hashBitLen; /* output hash bit count */
Skein_Start_New_Type(ctx,CFG_FINAL);
memset(&cfg.w,0,sizeof(cfg.w)); /* pre-pad cfg.w[] with zeroes */
cfg.w[0] = Skein_Swap64(SKEIN_SCHEMA_VER);
cfg.w[1] = Skein_Swap64(hashBitLen); /* hash result length in bits */
cfg.w[2] = Skein_Swap64(treeInfo); /* tree hash config info (or SKEIN_CFG_TREE_INFO_SEQUENTIAL) */
Skein_Show_Key(512,&ctx->h,key,keyBytes);
/* compute the initial chaining values from config block */
Skein_512_Process_Block(ctx,cfg.b,1,SKEIN_CFG_STR_LEN);
/* The chaining vars ctx->X are now initialized */
/* Set up to process the data message portion of the hash (default) */
ctx->h.bCnt = 0; /* buffer b[] starts out empty */
Skein_Start_New_Type(ctx,MSG);
return SKEIN_SUCCESS;
}
/* finalize the hash computation and output the result */
int Skein_512_Final(Skein_512_Ctxt_t *ctx, u08b_t *hashVal)
{
size_t i,n,byteCnt;
u64b_t X[SKEIN_512_STATE_WORDS];
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 */
/* now output the result */
byteCnt = (ctx->h.hashBitLen + 7) >> 3; /* total number of output bytes */
/* run Threefish in "counter mode" to generate output */
memset(ctx->b,0,sizeof(ctx->b)); /* zero out b[], so it can hold the counter */
memcpy(X,ctx->X,sizeof(X)); /* keep a local copy of counter mode "key" */
for (i=0; i*SKEIN_512_BLOCK_BYTES < byteCnt; i++)
{
((u64b_t *)ctx->b)[0]= Skein_Swap64((u64b_t) i); /* build the counter block */
Skein_Start_New_Type(ctx,OUT_FINAL);
Skein_512_Process_Block(ctx,ctx->b,1,sizeof(u64b_t)); /* run "counter mode" */
n = byteCnt - i*SKEIN_512_BLOCK_BYTES; /* number of output bytes left to go */
if (n >= SKEIN_512_BLOCK_BYTES)
n = SKEIN_512_BLOCK_BYTES;
Skein_Put64_LSB_First(hashVal+i*SKEIN_512_BLOCK_BYTES,ctx->X,n); /* "output" the ctr mode bytes */
Skein_Show_Final(512,&ctx->h,n,hashVal+i*SKEIN_512_BLOCK_BYTES);
memcpy(ctx->X,X,sizeof(X)); /* restore the counter mode key for next time */
}
return SKEIN_SUCCESS;
}
/* init the context for a straight hashing operation */
int Skein_256_Init(Skein_256_Ctxt_t *ctx, size_t hashBitLen)
{
union
{
u08b_t b[SKEIN_256_STATE_BYTES];
u64b_t w[SKEIN_256_STATE_WORDS];
} cfg; /* config block */
Skein_Assert(hashBitLen > 0,SKEIN_BAD_HASHLEN);
ctx->h.hashBitLen = hashBitLen; /* output hash bit count */
switch (hashBitLen)
{ /* use pre-computed values, where available */
case 256:
memcpy(ctx->X,SKEIN_256_IV_256,sizeof(ctx->X));
break;
case 224:
memcpy(ctx->X,SKEIN_256_IV_224,sizeof(ctx->X));
break;
case 160:
memcpy(ctx->X,SKEIN_256_IV_160,sizeof(ctx->X));
break;
case 128:
memcpy(ctx->X,SKEIN_256_IV_128,sizeof(ctx->X));
break;
default:
/* here if there is no precomputed IV value available */
/* build/process the config block, type == CONFIG (could be precomputed) */
Skein_Start_New_Type(ctx,CFG_FINAL); /* set tweaks: T0=0; T1=CFG | FINAL */
cfg.w[0] = Skein_Swap64(SKEIN_SCHEMA_VER); /* set the schema, version */
cfg.w[1] = Skein_Swap64(hashBitLen); /* hash result length in bits */
cfg.w[2] = Skein_Swap64(SKEIN_CFG_TREE_INFO_SEQUENTIAL);
memset(&cfg.w[3],0,sizeof(cfg) - 3*sizeof(cfg.w[0])); /* zero pad config block */
/* compute the initial chaining values from config block */
memset(ctx->X,0,sizeof(ctx->X)); /* zero the chaining variables */
Skein_256_Process_Block(ctx,cfg.b,1,SKEIN_CFG_STR_LEN);
break;
}
/* The chaining vars ctx->X are now initialized for the given hashBitLen. */
/* Set up to process the data message portion of the hash (default) */
Skein_Start_New_Type(ctx,MSG); /* T0=0, T1= MSG type */
return SKEIN_SUCCESS;
}
/* init the context for a straight hashing operation */
int Skein_512_Init(Skein_512_Ctxt_t *ctx) {
ctx->h.hashBitLen = 512; /* output hash bit count */
memcpy(ctx->X,SKEIN_512_IV_512,sizeof(ctx->X));
/* Set up to process the data message portion of the hash (default) */
Skein_Start_New_Type(ctx,MSG); /* T0=0, T1= MSG type */
return SKEIN_SUCCESS;
}
void skeinReset(SkeinCtx_t* ctx)
{
size_t Xlen = 0;
u64b_t* X = NULL;
/*
* The following two lines rely of the fact that the real Skein contexts are
* a union in out context and thus have tha maximum memory available.
* The beautiy of C :-) .
*/
X = ctx->m.s256.X;
Xlen = (size_t)(ctx->skeinSize/8);
/*
* If size is the same and hash bit length is zero then reuse
* the save chaining variables.
*/
/* Restore the chaing variable, reset byte counter */
memcpy(X, ctx->XSave, Xlen);
/* Setup context to process the message */
Skein_Start_New_Type(&ctx->m, MSG);
}
__device__ void cn_skein_init(skeinHashState *state, size_t hashBitLen)
{
const uint64_t SKEIN_512_IV_256[] =
{
SKEIN_MK_64(0xCCD044A1,0x2FDB3E13),
SKEIN_MK_64(0xE8359030,0x1A79A9EB),
SKEIN_MK_64(0x55AEA061,0x4F816E6F),
SKEIN_MK_64(0x2A2767A4,0xAE9B94DB),
SKEIN_MK_64(0xEC06025E,0x74DD7683),
SKEIN_MK_64(0xE7A436CD,0xC4746251),
SKEIN_MK_64(0xC36FBAF9,0x393AD185),
SKEIN_MK_64(0x3EEDBA18,0x33EDFC13)
};
Skein_512_Ctxt_t *ctx = &state->u.ctx_512;
ctx->h.hashBitLen = hashBitLen;
memcpy(ctx->X, SKEIN_512_IV_256, sizeof(ctx->X));
Skein_Start_New_Type(ctx, MSG);
}
/* just do the OUTPUT stage */
int
Skein1024_Output(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);
/* 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(256, &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);
}
