greg/pcompress
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
pcompress/crypto/skein/skein.c

754 lines
35 KiB
C
Raw Permalink Normal View History

Add support for Skein512 and Skein256 checksums Import Skein code from NIST CD submission Make checksum algorithms pluggable Fix handling of huge buffers (>2GB) in LZP Cleanup of some buffer sizing code Speed up CRC64 calculation in dedupe chunking
2012-08-31 17:06:06 +00:00
/***********************************************************************
**
** Implementation of the Skein hash function.
**
** Source code author: Doug Whiting, 2008.
**
** This algorithm and source code is released to the public domain.
**
************************************************************************/
#define SKEIN_PORT_CODE /* instantiate any code in skein_port.h */
#include <string.h> /* get the memcpy/memset functions */
#include "skein.h" /* get the Skein API definitions */
#include "skein_iv.h" /* get precomputed IVs */
/*****************************************************************/
/* External function to process blkCnt (nonzero) full block(s) of data. */
void Skein_256_Process_Block(Skein_256_Ctxt_t *ctx,const u08b_t *blkPtr,size_t blkCnt,size_t byteCntAdd);
void Skein_512_Process_Block(Skein_512_Ctxt_t *ctx,const u08b_t *blkPtr,size_t blkCnt,size_t byteCntAdd);
void Skein1024_Process_Block(Skein1024_Ctxt_t *ctx,const u08b_t *blkPtr,size_t blkCnt,size_t byteCntAdd);
/*****************************************************************/
/* 256-bit Skein */
/*****************************************************************/
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* 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 */
#ifndef SKEIN_NO_PRECOMP
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;
#endif
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 MAC and/or tree hash operation */
/* [identical to Skein_256_Init() when keyBytes == 0 && treeInfo == SKEIN_CFG_TREE_INFO_SEQUENTIAL] */
int Skein_256_InitExt(Skein_256_Ctxt_t *ctx,size_t hashBitLen,u64b_t treeInfo, const u08b_t *key, size_t keyBytes)
{
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);
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_256_Update(ctx,key,keyBytes); /* hash the key */
Skein_256_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_256_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(256,&ctx->h,key,keyBytes);
/* compute the initial chaining values from config block */
Skein_256_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;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* process the input bytes */
int Skein_256_Update(Skein_256_Ctxt_t *ctx, const u08b_t *msg, size_t msgByteCnt)
{
size_t n;
Skein_Assert(ctx->h.bCnt <= SKEIN_256_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
/* process full blocks, if any */
if (msgByteCnt + ctx->h.bCnt > SKEIN_256_BLOCK_BYTES)
{
if (ctx->h.bCnt) /* finish up any buffered message data */
{
n = SKEIN_256_BLOCK_BYTES - ctx->h.bCnt; /* # bytes free in buffer b[] */
if (n)
{
Skein_assert(n < msgByteCnt); /* check on our logic here */
memcpy(&ctx->b[ctx->h.bCnt],msg,n);
msgByteCnt -= n;
msg += n;
ctx->h.bCnt += n;
}
Skein_assert(ctx->h.bCnt == SKEIN_256_BLOCK_BYTES);
Skein_256_Process_Block(ctx,ctx->b,1,SKEIN_256_BLOCK_BYTES);
ctx->h.bCnt = 0;
}
/* now process any remaining full blocks, directly from input message data */
if (msgByteCnt > SKEIN_256_BLOCK_BYTES)
{
n = (msgByteCnt-1) / SKEIN_256_BLOCK_BYTES; /* number of full blocks to process */
Skein_256_Process_Block(ctx,msg,n,SKEIN_256_BLOCK_BYTES);
msgByteCnt -= n * SKEIN_256_BLOCK_BYTES;
msg += n * SKEIN_256_BLOCK_BYTES;
}
Skein_assert(ctx->h.bCnt == 0);
}
/* copy any remaining source message data bytes into b[] */
if (msgByteCnt)
{
Skein_assert(msgByteCnt + ctx->h.bCnt <= SKEIN_256_BLOCK_BYTES);
memcpy(&ctx->b[ctx->h.bCnt],msg,msgByteCnt);
ctx->h.bCnt += msgByteCnt;
}
return SKEIN_SUCCESS;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* finalize the hash computation and output the result */
int Skein_256_Final(Skein_256_Ctxt_t *ctx, u08b_t *hashVal)
{
size_t i,n,byteCnt;
u64b_t X[SKEIN_256_STATE_WORDS];
Skein_Assert(ctx->h.bCnt <= SKEIN_256_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_256_BLOCK_BYTES) /* zero pad b[] if necessary */
memset(&ctx->b[ctx->h.bCnt],0,SKEIN_256_BLOCK_BYTES - ctx->h.bCnt);
Skein_256_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_256_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_256_Process_Block(ctx,ctx->b,1,sizeof(u64b_t)); /* run "counter mode" */
n = byteCnt - i*SKEIN_256_BLOCK_BYTES; /* number of output bytes left to go */
if (n >= SKEIN_256_BLOCK_BYTES)
n = SKEIN_256_BLOCK_BYTES;
Skein_Put64_LSB_First(hashVal+i*SKEIN_256_BLOCK_BYTES,ctx->X,n); /* "output" the ctr mode bytes */
Skein_Show_Final(256,&ctx->h,n,hashVal+i*SKEIN_256_BLOCK_BYTES);
memcpy(ctx->X,X,sizeof(X)); /* restore the counter mode key for next time */
}
return SKEIN_SUCCESS;
}
#if defined(SKEIN_CODE_SIZE) || defined(SKEIN_PERF)
size_t Skein_256_API_CodeSize(void)
{
return ((u08b_t *) Skein_256_API_CodeSize) -
((u08b_t *) Skein_256_Init);
}
#endif
/*****************************************************************/
/* 512-bit Skein */
/*****************************************************************/
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* init the context for a straight hashing operation */
int Skein_512_Init(Skein_512_Ctxt_t *ctx, size_t hashBitLen)
{
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);
ctx->h.hashBitLen = hashBitLen; /* output hash bit count */
switch (hashBitLen)
{ /* use pre-computed values, where available */
#ifndef SKEIN_NO_PRECOMP
case 512: memcpy(ctx->X,SKEIN_512_IV_512,sizeof(ctx->X)); break;
case 384: memcpy(ctx->X,SKEIN_512_IV_384,sizeof(ctx->X)); break;
case 256: memcpy(ctx->X,SKEIN_512_IV_256,sizeof(ctx->X)); break;
case 224: memcpy(ctx->X,SKEIN_512_IV_224,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) */
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_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;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* init the context for a MAC and/or tree hash operation */
/* [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;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* process the input bytes */
int Skein_512_Update(Skein_512_Ctxt_t *ctx, const u08b_t *msg, size_t msgByteCnt)
{
size_t n;
Skein_Assert(ctx->h.bCnt <= SKEIN_512_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
/* process full blocks, if any */
if (msgByteCnt + ctx->h.bCnt > SKEIN_512_BLOCK_BYTES)
{
if (ctx->h.bCnt) /* finish up any buffered message data */
{
n = SKEIN_512_BLOCK_BYTES - ctx->h.bCnt; /* # bytes free in buffer b[] */
if (n)
{
Skein_assert(n < msgByteCnt); /* check on our logic here */
memcpy(&ctx->b[ctx->h.bCnt],msg,n);
msgByteCnt -= n;
msg += n;
ctx->h.bCnt += n;
}
Skein_assert(ctx->h.bCnt == SKEIN_512_BLOCK_BYTES);
Skein_512_Process_Block(ctx,ctx->b,1,SKEIN_512_BLOCK_BYTES);
ctx->h.bCnt = 0;
}
/* now process any remaining full blocks, directly from input message data */
if (msgByteCnt > SKEIN_512_BLOCK_BYTES)
{
n = (msgByteCnt-1) / SKEIN_512_BLOCK_BYTES; /* number of full blocks to process */
Skein_512_Process_Block(ctx,msg,n,SKEIN_512_BLOCK_BYTES);
msgByteCnt -= n * SKEIN_512_BLOCK_BYTES;
msg += n * SKEIN_512_BLOCK_BYTES;
}
Skein_assert(ctx->h.bCnt == 0);
}
/* copy any remaining source message data bytes into b[] */
if (msgByteCnt)
{
Skein_assert(msgByteCnt + ctx->h.bCnt <= SKEIN_512_BLOCK_BYTES);
memcpy(&ctx->b[ctx->h.bCnt],msg,msgByteCnt);
ctx->h.bCnt += msgByteCnt;
}
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;
}
#if defined(SKEIN_CODE_SIZE) || defined(SKEIN_PERF)
size_t Skein_512_API_CodeSize(void)
{
return ((u08b_t *) Skein_512_API_CodeSize) -
((u08b_t *) Skein_512_Init);
}
#endif
/*****************************************************************/
/* 1024-bit Skein */
/*****************************************************************/
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* init the context for a straight hashing operation */
int Skein1024_Init(Skein1024_Ctxt_t *ctx, size_t hashBitLen)
{
union
{
u08b_t b[SKEIN1024_STATE_BYTES];
u64b_t w[SKEIN1024_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: memcpy(ctx->X,SKEIN1024_IV_512 ,sizeof(ctx->X)); break;
case 384: memcpy(ctx->X,SKEIN1024_IV_384 ,sizeof(ctx->X)); break;
case 1024: memcpy(ctx->X,SKEIN1024_IV_1024,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) */
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 */
Skein1024_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 MAC and/or tree hash operation */
/* [identical to Skein1024_Init() when keyBytes == 0 && treeInfo == SKEIN_CFG_TREE_INFO_SEQUENTIAL] */
int Skein1024_InitExt(Skein1024_Ctxt_t *ctx,size_t hashBitLen,u64b_t treeInfo, const u08b_t *key, size_t keyBytes)
{
union
{
u08b_t b[SKEIN1024_STATE_BYTES];
u64b_t w[SKEIN1024_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 */
Skein1024_Update(ctx,key,keyBytes); /* hash the key */
Skein1024_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<SKEIN1024_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(1024,&ctx->h,key,keyBytes);
/* compute the initial chaining values from config block */
Skein1024_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;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* process the input bytes */
int Skein1024_Update(Skein1024_Ctxt_t *ctx, const u08b_t *msg, size_t msgByteCnt)
{
size_t n;
Skein_Assert(ctx->h.bCnt <= SKEIN1024_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
/* process full blocks, if any */
if (msgByteCnt + ctx->h.bCnt > SKEIN1024_BLOCK_BYTES)
{
if (ctx->h.bCnt) /* finish up any buffered message data */
{
n = SKEIN1024_BLOCK_BYTES - ctx->h.bCnt; /* # bytes free in buffer b[] */
if (n)
{
Skein_assert(n < msgByteCnt); /* check on our logic here */
memcpy(&ctx->b[ctx->h.bCnt],msg,n);
msgByteCnt -= n;
msg += n;
ctx->h.bCnt += n;
}
Skein_assert(ctx->h.bCnt == SKEIN1024_BLOCK_BYTES);
Skein1024_Process_Block(ctx,ctx->b,1,SKEIN1024_BLOCK_BYTES);
ctx->h.bCnt = 0;
}
/* now process any remaining full blocks, directly from input message data */
if (msgByteCnt > SKEIN1024_BLOCK_BYTES)
{
n = (msgByteCnt-1) / SKEIN1024_BLOCK_BYTES; /* number of full blocks to process */
Skein1024_Process_Block(ctx,msg,n,SKEIN1024_BLOCK_BYTES);
msgByteCnt -= n * SKEIN1024_BLOCK_BYTES;
msg += n * SKEIN1024_BLOCK_BYTES;
}
Skein_assert(ctx->h.bCnt == 0);
}
/* copy any remaining source message data bytes into b[] */
if (msgByteCnt)
{
Skein_assert(msgByteCnt + ctx->h.bCnt <= SKEIN1024_BLOCK_BYTES);
memcpy(&ctx->b[ctx->h.bCnt],msg,msgByteCnt);
ctx->h.bCnt += msgByteCnt;
}
return SKEIN_SUCCESS;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* finalize the hash computation and output the result */
int Skein1024_Final(Skein1024_Ctxt_t *ctx, u08b_t *hashVal)
{
size_t i,n,byteCnt;
u64b_t X[SKEIN1024_STATE_WORDS];
Skein_Assert(ctx->h.bCnt <= SKEIN1024_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
ctx->h.T[1] |= SKEIN_T1_FLAG_FINAL; /* tag as the final block */
if (ctx->h.bCnt < SKEIN1024_BLOCK_BYTES) /* zero pad b[] if necessary */
memset(&ctx->b[ctx->h.bCnt],0,SKEIN1024_BLOCK_BYTES - ctx->h.bCnt);
Skein1024_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*SKEIN1024_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);
Skein1024_Process_Block(ctx,ctx->b,1,sizeof(u64b_t)); /* run "counter mode" */
n = byteCnt - i*SKEIN1024_BLOCK_BYTES; /* number of output bytes left to go */
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);
memcpy(ctx->X,X,sizeof(X)); /* restore the counter mode key for next time */
}
return SKEIN_SUCCESS;
}
#if defined(SKEIN_CODE_SIZE) || defined(SKEIN_PERF)
size_t Skein1024_API_CodeSize(void)
{
return ((u08b_t *) Skein1024_API_CodeSize) -
((u08b_t *) Skein1024_Init);
}
#endif
/**************** Functions to support MAC/tree hashing ***************/
/* (this code is identical for Optimized and Reference versions) */
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* finalize the hash computation and output the block, no OUTPUT stage */
int Skein_256_Final_Pad(Skein_256_Ctxt_t *ctx, u08b_t *hashVal)
{
Skein_Assert(ctx->h.bCnt <= SKEIN_256_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_256_BLOCK_BYTES) /* zero pad b[] if necessary */
memset(&ctx->b[ctx->h.bCnt],0,SKEIN_256_BLOCK_BYTES - ctx->h.bCnt);
Skein_256_Process_Block(ctx,ctx->b,1,ctx->h.bCnt); /* process the final block */
Skein_Put64_LSB_First(hashVal,ctx->X,SKEIN_256_BLOCK_BYTES); /* "output" the state bytes */
return SKEIN_SUCCESS;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* 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 block, no OUTPUT stage */
int Skein1024_Final_Pad(Skein1024_Ctxt_t *ctx, u08b_t *hashVal)
{
Skein_Assert(ctx->h.bCnt <= SKEIN1024_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
ctx->h.T[1] |= SKEIN_T1_FLAG_FINAL; /* tag as the final block */
if (ctx->h.bCnt < SKEIN1024_BLOCK_BYTES) /* zero pad b[] if necessary */
memset(&ctx->b[ctx->h.bCnt],0,SKEIN1024_BLOCK_BYTES - ctx->h.bCnt);
Skein1024_Process_Block(ctx,ctx->b,1,ctx->h.bCnt); /* process the final block */
Skein_Put64_LSB_First(hashVal,ctx->X,SKEIN1024_BLOCK_BYTES); /* "output" the state bytes */
return SKEIN_SUCCESS;
}
#if SKEIN_TREE_HASH
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* just do the OUTPUT stage */
int Skein_256_Output(Skein_256_Ctxt_t *ctx, u08b_t *hashVal)
{
size_t i,n,byteCnt;
u64b_t X[SKEIN_256_STATE_WORDS];
Skein_Assert(ctx->h.bCnt <= SKEIN_256_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
/* 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_256_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_256_Process_Block(ctx,ctx->b,1,sizeof(u64b_t)); /* run "counter mode" */
n = byteCnt - i*SKEIN_256_BLOCK_BYTES; /* number of output bytes left to go */
if (n >= SKEIN_256_BLOCK_BYTES)
n = SKEIN_256_BLOCK_BYTES;
Skein_Put64_LSB_First(hashVal+i*SKEIN_256_BLOCK_BYTES,ctx->X,n); /* "output" the ctr mode bytes */
Skein_Show_Final(256,&ctx->h,n,hashVal+i*SKEIN_256_BLOCK_BYTES);
memcpy(ctx->X,X,sizeof(X)); /* restore the counter mode key for next time */
}
return SKEIN_SUCCESS;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* just do the OUTPUT stage */
int Skein_512_Output(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 */
/* 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(256,&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;
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
/* just do the OUTPUT stage */
int Skein1024_Output(Skein1024_Ctxt_t *ctx, u08b_t *hashVal)
{
size_t i,n,byteCnt;
u64b_t X[SKEIN1024_STATE_WORDS];
Skein_Assert(ctx->h.bCnt <= SKEIN1024_BLOCK_BYTES,SKEIN_FAIL); /* catch uninitialized context */
/* 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*SKEIN1024_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);
Skein1024_Process_Block(ctx,ctx->b,1,sizeof(u64b_t)); /* run "counter mode" */
n = byteCnt - i*SKEIN1024_BLOCK_BYTES; /* number of output bytes left to go */
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);
memcpy(ctx->X,X,sizeof(X)); /* restore the counter mode key for next time */
}
return SKEIN_SUCCESS;
}
#endif
Reference in a new issue Copy permalink