+/***********************************************************************\r
+**\r
+** Implementation of the AHS API using the Skein hash function.\r
+**\r
+** Source code author: Doug Whiting, 2008.\r
+**\r
+** This algorithm and source code is released to the public domain.\r
+** \r
+************************************************************************/\r
+\r
+#include <string.h> /* get the memcpy/memset functions */\r
+#include "skein.h" /* get the Skein API definitions */\r
+#include "skeinapi_ref.h"/* get the AHS API definitions */\r
+
+//#define SKEIN_DEBUG 1
+#ifdef SKEIN_DEBUG
+# include <stdio.h>
+# include <stdlib.h>
+# include <string.h>
+#endif
+
+\r
+/******************************************************************/\r
+/* AHS API code */\r
+/******************************************************************/\r
+\r
+/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/\r
+/* select the context size and init the context */\r
+HashReturn Init(hashState *state, int hashbitlen)\r
+ {\r
+#if SKEIN_256_NIST_MAX_HASH_BITS\r
+ if (hashbitlen <= SKEIN_256_NIST_MAX_HASHBITS)\r
+ {\r
+ Skein_Assert(hashbitlen > 0,BAD_HASHLEN);\r
+ state->statebits = 64*SKEIN_256_STATE_WORDS;\r
+ return Skein_256_Init(&state->u.ctx_256,(size_t) hashbitlen);\r
+ }\r
+#endif\r
+ if (hashbitlen <= SKEIN_512_NIST_MAX_HASHBITS)\r
+ {\r
+ state->statebits = 64*SKEIN_512_STATE_WORDS;\r
+ return Skein_512_Init(&state->u.ctx_512,(size_t) hashbitlen);\r
+ }\r
+ else\r
+ {\r
+ state->statebits = 64*SKEIN1024_STATE_WORDS;\r
+ return Skein1024_Init(&state->u.ctx1024,(size_t) hashbitlen);\r
+ }\r
+ }\r
+\r
+/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/\r
+/* process data to be hashed */\r
+HashReturn Update(hashState *state, const BitSequence *data, DataLength databitlen)\r
+ {\r
+ /* only the final Update() call is allowed do partial bytes, else assert an error */\r
+ Skein_Assert((state->u.h.T[1] & SKEIN_T1_FLAG_BIT_PAD) == 0 || databitlen == 0, FAIL);\r
+\r
+ Skein_Assert(state->statebits % 256 == 0 && (state->statebits-256) < 1024,FAIL);\r
+ if ((databitlen & 7) == 0) /* partial bytes? */\r
+ {\r
+ switch ((state->statebits >> 8) & 3)\r
+ {\r
+ case 2: return Skein_512_Update(&state->u.ctx_512,data,databitlen >> 3);\r
+ case 1: return Skein_256_Update(&state->u.ctx_256,data,databitlen >> 3);\r
+ case 0: return Skein1024_Update(&state->u.ctx1024,data,databitlen >> 3);\r
+ default: return FAIL;\r
+ }\r
+ }\r
+ else\r
+ { /* handle partial final byte */\r
+ size_t bCnt = (databitlen >> 3) + 1; /* number of bytes to handle (nonzero here!) */\r
+ u08b_t b,mask;\r
+\r
+ mask = (u08b_t) (1u << (7 - (databitlen & 7))); /* partial byte bit mask */\r
+ b = (u08b_t) ((data[bCnt-1] & (0-mask)) | mask); /* apply bit padding on final byte */\r
+\r
+ switch ((state->statebits >> 8) & 3)\r
+ {\r
+ case 2: Skein_512_Update(&state->u.ctx_512,data,bCnt-1); /* process all but the final byte */\r
+ Skein_512_Update(&state->u.ctx_512,&b , 1 ); /* process the (masked) partial byte */\r
+ break;\r
+ case 1: Skein_256_Update(&state->u.ctx_256,data,bCnt-1); /* process all but the final byte */\r
+ Skein_256_Update(&state->u.ctx_256,&b , 1 ); /* process the (masked) partial byte */\r
+ break;\r
+ case 0: Skein1024_Update(&state->u.ctx1024,data,bCnt-1); /* process all but the final byte */\r
+ Skein1024_Update(&state->u.ctx1024,&b , 1 ); /* process the (masked) partial byte */\r
+ break;\r
+ default: return FAIL;\r
+ }\r
+ Skein_Set_Bit_Pad_Flag(state->u.h); /* set tweak flag for the final call */\r
+ \r
+ return SUCCESS;\r
+ }\r
+ }\r
+\r
+/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/\r
+/* finalize hash computation and output the result (hashbitlen bits) */\r
+HashReturn Final(hashState *state, BitSequence *hashval)\r
+ {\r
+ Skein_Assert(state->statebits % 256 == 0 && (state->statebits-256) < 1024,FAIL);\r
+ switch ((state->statebits >> 8) & 3)\r
+ {\r
+ case 2: return Skein_512_Final(&state->u.ctx_512,hashval);\r
+ case 1: return Skein_256_Final(&state->u.ctx_256,hashval);\r
+ case 0: return Skein1024_Final(&state->u.ctx1024,hashval);\r
+ default: return FAIL;\r
+ }\r
+ }\r
+\r
+/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/\r
+/* all-in-one hash function */\r
+HashReturn Hash(int hashbitlen, const BitSequence *data, /* all-in-one call */\r
+ DataLength databitlen,BitSequence *hashval)\r
+ {\r
+ hashState state;\r
+ HashReturn r = Init(&state,hashbitlen);\r
+ if (r == SUCCESS)\r
+ { /* these calls do not fail when called properly */\r
+ r = Update(&state,data,databitlen);\r
+ Final(&state,hashval);\r
+#ifdef SKEIN_DEBUG
+ if (r == SUCCESS && getenv("SKEIN_DEEP_DUMP"))
+ {
+ int i;
+ printf("==== Hashbitlen = %d, DataBitLen = %llu, Data:\n%s\n==== Hash:\n",
+ hashbitlen, (long long unsigned)databitlen, (const char*)data);
+ for (i = 0; i < hashbitlen / 8; i++)
+ printf("%02X", hashval[i]);
+ printf("\n");
+ }
+#endif
+ }\r
+ return r;\r
+ }\r