| /*********************************************************************** |
| ** |
| ** 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 <linux/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 u8 *blkPtr,size_t blkCnt,size_t byteCntAdd); |
| void Skein_512_Process_Block(Skein_512_Ctxt_t *ctx,const u8 *blkPtr,size_t blkCnt,size_t byteCntAdd); |
| void Skein1024_Process_Block(Skein1024_Ctxt_t *ctx,const u8 *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 |
| { |
| u8 b[SKEIN_256_STATE_BYTES]; |
| u64 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,u64 treeInfo, const u8 *key, size_t keyBytes) |
| { |
| union |
| { |
| u8 b[SKEIN_256_STATE_BYTES]; |
| u64 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[] */ |
| } |
| /* 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 u8 *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, u8 *hashVal) |
| { |
| size_t i,n,byteCnt; |
| u64 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++) |
| { |
| ((u64 *)ctx->b)[0]= Skein_Swap64((u64) i); /* build the counter block */ |
| Skein_Start_New_Type(ctx,OUT_FINAL); |
| Skein_256_Process_Block(ctx,ctx->b,1,sizeof(u64)); /* 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 |
| { |
| u8 b[SKEIN_512_STATE_BYTES]; |
| u64 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,u64 treeInfo, const u8 *key, size_t keyBytes) |
| { |
| union |
| { |
| u8 b[SKEIN_512_STATE_BYTES]; |
| u64 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[] */ |
| } |
| /* 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 u8 *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, u8 *hashVal) |
| { |
| size_t i,n,byteCnt; |
| u64 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++) |
| { |
| ((u64 *)ctx->b)[0]= Skein_Swap64((u64) i); /* build the counter block */ |
| Skein_Start_New_Type(ctx,OUT_FINAL); |
| Skein_512_Process_Block(ctx,ctx->b,1,sizeof(u64)); /* 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 |
| { |
| u8 b[SKEIN1024_STATE_BYTES]; |
| u64 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,u64 treeInfo, const u8 *key, size_t keyBytes) |
| { |
| union |
| { |
| u8 b[SKEIN1024_STATE_BYTES]; |
| u64 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[] */ |
| } |
| /* 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 u8 *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, u8 *hashVal) |
| { |
| size_t i,n,byteCnt; |
| u64 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++) |
| { |
| ((u64 *)ctx->b)[0]= Skein_Swap64((u64) i); /* build the counter block */ |
| Skein_Start_New_Type(ctx,OUT_FINAL); |
| Skein1024_Process_Block(ctx,ctx->b,1,sizeof(u64)); /* 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, u8 *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, u8 *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, u8 *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, u8 *hashVal) |
| { |
| size_t i,n,byteCnt; |
| u64 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++) |
| { |
| ((u64 *)ctx->b)[0]= Skein_Swap64((u64) i); /* build the counter block */ |
| Skein_Start_New_Type(ctx,OUT_FINAL); |
| Skein_256_Process_Block(ctx,ctx->b,1,sizeof(u64)); /* 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, u8 *hashVal) |
| { |
| size_t i,n,byteCnt; |
| u64 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++) |
| { |
| ((u64 *)ctx->b)[0]= Skein_Swap64((u64) i); /* build the counter block */ |
| Skein_Start_New_Type(ctx,OUT_FINAL); |
| Skein_512_Process_Block(ctx,ctx->b,1,sizeof(u64)); /* 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, u8 *hashVal) |
| { |
| size_t i,n,byteCnt; |
| u64 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++) |
| { |
| ((u64 *)ctx->b)[0]= Skein_Swap64((u64) i); /* build the counter block */ |
| Skein_Start_New_Type(ctx,OUT_FINAL); |
| Skein1024_Process_Block(ctx,ctx->b,1,sizeof(u64)); /* 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 |