/*********************************************************************** | |
** | |
** 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 <ccrtp/crypto/skein.h> /* get the Skein API definitions */ | |
#include <ccrtp/crypto/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 */ | |
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 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) */ | |
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; | |
} | |
/*****************************************************************/ | |
/* 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 */ | |
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; | |
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) */ | |
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; | |
} | |
/*****************************************************************/ | |
/* 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 */ | |
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; | |
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) */ | |
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; | |
} | |
/**************** 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 |