#ifndef _SKEIN_H_
#define _SKEIN_H_ 1
/**************************************************************************
**
** Interface declarations and internal definitions for Skein hashing.
**
** Source code author: Doug Whiting, 2008.
**
** This algorithm and source code is released to the public domain.
**
***************************************************************************
**
** The following compile-time switches may be defined to control some
** tradeoffs between speed, code size, error checking, and security.
**
** The "default" note explains what happens when the switch is not defined.
**
** SKEIN_DEBUG -- make callouts from inside Skein code
** to examine/display intermediate values.
** [default: no callouts (no overhead)]
**
** SKEIN_ERR_CHECK -- how error checking is handled inside Skein
** code. If not defined, most error checking
** is disabled (for performance). Otherwise,
** the switch value is interpreted as:
** 0: use assert() to flag errors
** 1: return SKEIN_FAIL to flag errors
**
***************************************************************************/
#ifndef RotL_64
#define RotL_64(x, N) (((x) << (N)) | ((x) >> (64-(N))))
#endif
/* below two prototype assume we are handed aligned data */
#define Skein_Put64_LSB_First(dst08, src64, bCnt) memcpy(dst08, src64, bCnt)
#define Skein_Get64_LSB_First(dst64, src08, wCnt) memcpy(dst64, src08, 8*(wCnt))
#define Skein_Swap64(w64) (w64)
enum
{
SKEIN_SUCCESS = 0, /* return codes from Skein calls */
SKEIN_FAIL = 1,
SKEIN_BAD_HASHLEN = 2
};
#define SKEIN_MODIFIER_WORDS (2) /* number of modifier (tweak) words */
#define SKEIN_256_STATE_WORDS (4)
#define SKEIN_512_STATE_WORDS (8)
#define SKEIN1024_STATE_WORDS (16)
#define SKEIN_MAX_STATE_WORDS (16)
#define SKEIN_256_STATE_BYTES (8*SKEIN_256_STATE_WORDS)
#define SKEIN_512_STATE_BYTES (8*SKEIN_512_STATE_WORDS)
#define SKEIN1024_STATE_BYTES (8*SKEIN1024_STATE_WORDS)
#define SKEIN_256_STATE_BITS (64*SKEIN_256_STATE_WORDS)
#define SKEIN_512_STATE_BITS (64*SKEIN_512_STATE_WORDS)
#define SKEIN1024_STATE_BITS (64*SKEIN1024_STATE_WORDS)
#define SKEIN_256_BLOCK_BYTES (8*SKEIN_256_STATE_WORDS)
#define SKEIN_512_BLOCK_BYTES (8*SKEIN_512_STATE_WORDS)
#define SKEIN1024_BLOCK_BYTES (8*SKEIN1024_STATE_WORDS)
struct skein_ctx_hdr
{
size_t hashBitLen; /* size of hash result, in bits */
size_t bCnt; /* current byte count in buffer b[] */
u64 T[SKEIN_MODIFIER_WORDS]; /* tweak words: T[0]=byte cnt, T[1]=flags */
};
struct skein_256_ctx /* 256-bit Skein hash context structure */
{
struct skein_ctx_hdr h; /* common header context variables */
u64 X[SKEIN_256_STATE_WORDS]; /* chaining variables */
u8 b[SKEIN_256_BLOCK_BYTES]; /* partial block buffer (8-byte aligned) */
};
struct skein_512_ctx /* 512-bit Skein hash context structure */
{
struct skein_ctx_hdr h; /* common header context variables */
u64 X[SKEIN_512_STATE_WORDS]; /* chaining variables */
u8 b[SKEIN_512_BLOCK_BYTES]; /* partial block buffer (8-byte aligned) */
};
struct skein1024_ctx /* 1024-bit Skein hash context structure */
{
struct skein_ctx_hdr h; /* common header context variables */
u64 X[SKEIN1024_STATE_WORDS]; /* chaining variables */
u8 b[SKEIN1024_BLOCK_BYTES]; /* partial block buffer (8-byte aligned) */
};
/* Skein APIs for (incremental) "straight hashing" */
int Skein_256_Init(struct skein_256_ctx *ctx, size_t hashBitLen);
int Skein_512_Init(struct skein_512_ctx *ctx, size_t hashBitLen);
int Skein1024_Init(struct skein1024_ctx *ctx, size_t hashBitLen);
int Skein_256_Update(struct skein_256_ctx *ctx, const u8 *msg, size_t msgByteCnt);
int Skein_512_Update(struct skein_512_ctx *ctx, const u8 *msg, size_t msgByteCnt);
int Skein1024_Update(struct skein1024_ctx *ctx, const u8 *msg, size_t msgByteCnt);
int Skein_256_Final(struct skein_256_ctx *ctx, u8 *hashVal);
int Skein_512_Final(struct skein_512_ctx *ctx, u8 *hashVal);
int Skein1024_Final(struct skein1024_ctx *ctx, u8 *hashVal);
/*
** Skein APIs for "extended" initialization: MAC keys, tree hashing.
** After an InitExt() call, just use Update/Final calls as with Init().
**
** Notes: Same parameters as _Init() calls, plus treeInfo/key/keyBytes.
** When keyBytes == 0 and treeInfo == SKEIN_SEQUENTIAL,
** the results of InitExt() are identical to calling Init().
** The function Init() may be called once to "precompute" the IV for
** a given hashBitLen value, then by saving a copy of the context
** the IV computation may be avoided in later calls.
** Similarly, the function InitExt() may be called once per MAC key
** to precompute the MAC IV, then a copy of the context saved and
** reused for each new MAC computation.
**/
int Skein_256_InitExt(struct skein_256_ctx *ctx, size_t hashBitLen, u64 treeInfo, const u8 *key, size_t keyBytes);
int Skein_512_InitExt(struct skein_512_ctx *ctx, size_t hashBitLen, u64 treeInfo, const u8 *key, size_t keyBytes);
int Skein1024_InitExt(struct skein1024_ctx *ctx, size_t hashBitLen, u64 treeInfo, const u8 *key, size_t keyBytes);
/*
** Skein APIs for MAC and tree hash:
** Final_Pad: pad, do final block, but no OUTPUT type
** Output: do just the output stage
*/
int Skein_256_Final_Pad(struct skein_256_ctx *ctx, u8 *hashVal);
int Skein_512_Final_Pad(struct skein_512_ctx *ctx, u8 *hashVal);
int Skein1024_Final_Pad(struct skein1024_ctx *ctx, u8 *hashVal);
#ifndef SKEIN_TREE_HASH
#define SKEIN_TREE_HASH (1)
#endif
#if SKEIN_TREE_HASH
int Skein_256_Output(struct skein_256_ctx *ctx, u8 *hashVal);
int Skein_512_Output(struct skein_512_ctx *ctx, u8 *hashVal);
int Skein1024_Output(struct skein1024_ctx *ctx, u8 *hashVal);
#endif
/*****************************************************************
** "Internal" Skein definitions
** -- not needed for sequential hashing API, but will be
** helpful for other uses of Skein (e.g., tree hash mode).
** -- included here so that they can be shared between
** reference and optimized code.
******************************************************************/
/* tweak word T[1]: bit field starting positions */
#define SKEIN_T1_BIT(BIT) ((BIT) - 64) /* offset 64 because it's the second word */
#define SKEIN_T1_POS_TREE_LVL SKEIN_T1_BIT(112) /* bits 112..118: level in hash tree */
#define SKEIN_T1_POS_BIT_PAD SKEIN_T1_BIT(119) /* bit 119 : partial final input byte */
#define SKEIN_T1_POS_BLK_TYPE SKEIN_T1_BIT(120) /* bits 120..125: type field */
#define SKEIN_T1_POS_FIRST SKEIN_T1_BIT(126) /* bits 126 : first block flag */
#define SKEIN_T1_POS_FINAL SKEIN_T1_BIT(127) /* bit 127 : final block flag */
/* tweak word T[1]: flag bit definition(s) */
#define SKEIN_T1_FLAG_FIRST (((u64) 1) << SKEIN_T1_POS_FIRST)
#define SKEIN_T1_FLAG_FINAL (((u64) 1) << SKEIN_T1_POS_FINAL)
#define SKEIN_T1_FLAG_BIT_PAD (((u64) 1) << SKEIN_T1_POS_BIT_PAD)
/* tweak word T[1]: tree level bit field mask */
#define SKEIN_T1_TREE_LVL_MASK (((u64)0x7F) << SKEIN_T1_POS_TREE_LVL)
#define SKEIN_T1_TREE_LEVEL(n) (((u64) (n)) << SKEIN_T1_POS_TREE_LVL)
/* tweak word T[1]: block type field */
#define SKEIN_BLK_TYPE_KEY (0) /* key, for MAC and KDF */
#define SKEIN_BLK_TYPE_CFG (4) /* configuration block */
#define SKEIN_BLK_TYPE_PERS (8) /* personalization string */
#define SKEIN_BLK_TYPE_PK (12) /* public key (for digital signature hashing) */
#define SKEIN_BLK_TYPE_KDF (16) /* key identifier for KDF */
#define SKEIN_BLK_TYPE_NONCE (20) /* nonce for PRNG */
#define SKEIN_BLK_TYPE_MSG (48) /* message processing */
#define SKEIN_BLK_TYPE_OUT (63) /* output stage */
#define SKEIN_BLK_TYPE_MASK (63) /* bit field mask */
#define SKEIN_T1_BLK_TYPE(T) (((u64) (SKEIN_BLK_TYPE_##T)) << SKEIN_T1_POS_BLK_TYPE)
#define SKEIN_T1_BLK_TYPE_KEY SKEIN_T1_BLK_TYPE(KEY) /* key, for MAC and KDF */
#define SKEIN_T1_BLK_TYPE_CFG SKEIN_T1_BLK_TYPE(CFG) /* configuration block */
#define SKEIN_T1_BLK_TYPE_PERS SKEIN_T1_BLK_TYPE(PERS) /* personalization string */
#define SKEIN_T1_BLK_TYPE_PK SKEIN_T1_BLK_TYPE(PK) /* public key (for digital signature hashing) */
#define SKEIN_T1_BLK_TYPE_KDF SKEIN_T1_BLK_TYPE(KDF) /* key identifier for KDF */
#define SKEIN_T1_BLK_TYPE_NONCE SKEIN_T1_BLK_TYPE(NONCE)/* nonce for PRNG */
#define SKEIN_T1_BLK_TYPE_MSG SKEIN_T1_BLK_TYPE(MSG) /* message processing */
#define SKEIN_T1_BLK_TYPE_OUT SKEIN_T1_BLK_TYPE(OUT) /* output stage */
#define SKEIN_T1_BLK_TYPE_MASK SKEIN_T1_BLK_TYPE(MASK) /* field bit mask */
#define SKEIN_T1_BLK_TYPE_CFG_FINAL (SKEIN_T1_BLK_TYPE_CFG | SKEIN_T1_FLAG_FINAL)
#define SKEIN_T1_BLK_TYPE_OUT_FINAL (SKEIN_T1_BLK_TYPE_OUT | SKEIN_T1_FLAG_FINAL)
#define SKEIN_VERSION (1)
#ifndef SKEIN_ID_STRING_LE /* allow compile-time personalization */
#define SKEIN_ID_STRING_LE (0x33414853) /* "SHA3" (little-endian)*/
#endif
#define SKEIN_MK_64(hi32, lo32) ((lo32) + (((u64) (hi32)) << 32))
#define SKEIN_SCHEMA_VER SKEIN_MK_64(SKEIN_VERSION, SKEIN_ID_STRING_LE)
#define SKEIN_KS_PARITY SKEIN_MK_64(0x1BD11BDA, 0xA9FC1A22)
#define SKEIN_CFG_STR_LEN (4*8)
/* bit field definitions in config block treeInfo word */
#define SKEIN_CFG_TREE_LEAF_SIZE_POS (0)
#define SKEIN_CFG_TREE_NODE_SIZE_POS (8)
#define SKEIN_CFG_TREE_MAX_LEVEL_POS (16)
#define SKEIN_CFG_TREE_LEAF_SIZE_MSK (((u64) 0xFF) << SKEIN_CFG_TREE_LEAF_SIZE_POS)
#define SKEIN_CFG_TREE_NODE_SIZE_MSK (((u64) 0xFF) << SKEIN_CFG_TREE_NODE_SIZE_POS)
#define SKEIN_CFG_TREE_MAX_LEVEL_MSK (((u64) 0xFF) << SKEIN_CFG_TREE_MAX_LEVEL_POS)
#define SKEIN_CFG_TREE_INFO(leaf, node, maxLvl) \
((((u64)(leaf)) << SKEIN_CFG_TREE_LEAF_SIZE_POS) | \
(((u64)(node)) << SKEIN_CFG_TREE_NODE_SIZE_POS) | \
(((u64)(maxLvl)) << SKEIN_CFG_TREE_MAX_LEVEL_POS))
#define SKEIN_CFG_TREE_INFO_SEQUENTIAL SKEIN_CFG_TREE_INFO(0, 0, 0) /* use as treeInfo in InitExt() call for sequential processing */
/*
** Skein macros for getting/setting tweak words, etc.
** These are useful for partial input bytes, hash tree init/update, etc.
**/
#define Skein_Get_Tweak(ctxPtr, TWK_NUM) ((ctxPtr)->h.T[TWK_NUM])
#define Skein_Set_Tweak(ctxPtr, TWK_NUM, tVal) {(ctxPtr)->h.T[TWK_NUM] = (tVal); }
#define Skein_Get_T0(ctxPtr) Skein_Get_Tweak(ctxPtr, 0)
#define Skein_Get_T1(ctxPtr) Skein_Get_Tweak(ctxPtr, 1)
#define Skein_Set_T0(ctxPtr, T0) Skein_Set_Tweak(ctxPtr, 0, T0)
#define Skein_Set_T1(ctxPtr, T1) Skein_Set_Tweak(ctxPtr, 1, T1)
/* set both tweak words at once */
#define Skein_Set_T0_T1(ctxPtr, T0, T1) \
{ \
Skein_Set_T0(ctxPtr, (T0)); \
Skein_Set_T1(ctxPtr, (T1)); \
}
#define Skein_Set_Type(ctxPtr, BLK_TYPE) \
Skein_Set_T1(ctxPtr, SKEIN_T1_BLK_TYPE_##BLK_TYPE)
/* set up for starting with a new type: h.T[0]=0; h.T[1] = NEW_TYPE; h.bCnt=0; */
#define Skein_Start_New_Type(ctxPtr, BLK_TYPE) \
{ Skein_Set_T0_T1(ctxPtr, 0, SKEIN_T1_FLAG_FIRST | SKEIN_T1_BLK_TYPE_##BLK_TYPE); (ctxPtr)->h.bCnt = 0; }
#define Skein_Clear_First_Flag(hdr) { (hdr).T[1] &= ~SKEIN_T1_FLAG_FIRST; }
#define Skein_Set_Bit_Pad_Flag(hdr) { (hdr).T[1] |= SKEIN_T1_FLAG_BIT_PAD; }
#define Skein_Set_Tree_Level(hdr, height) { (hdr).T[1] |= SKEIN_T1_TREE_LEVEL(height); }
/*****************************************************************
** "Internal" Skein definitions for debugging and error checking
******************************************************************/
#ifdef SKEIN_DEBUG /* examine/display intermediate values? */
#include "skein_debug.h"
#else /* default is no callouts */
#define Skein_Show_Block(bits, ctx, X, blkPtr, wPtr, ksEvenPtr, ksOddPtr)
#define Skein_Show_Round(bits, ctx, r, X)
#define Skein_Show_R_Ptr(bits, ctx, r, X_ptr)
#define Skein_Show_Final(bits, ctx, cnt, outPtr)
#define Skein_Show_Key(bits, ctx, key, keyBytes)
#endif
#define Skein_Assert(x, retCode)/* default: ignore all Asserts, for performance */
#define Skein_assert(x)
/*****************************************************************
** Skein block function constants (shared across Ref and Opt code)
******************************************************************/
enum
{
/* Skein_256 round rotation constants */
R_256_0_0 = 14, R_256_0_1 = 16,
R_256_1_0 = 52, R_256_1_1 = 57,
R_256_2_0 = 23, R_256_2_1 = 40,
R_256_3_0 = 5, R_256_3_1 = 37,
R_256_4_0 = 25, R_256_4_1 = 33,
R_256_5_0 = 46, R_256_5_1 = 12,
R_256_6_0 = 58, R_256_6_1 = 22,
R_256_7_0 = 32, R_256_7_1 = 32,
/* Skein_512 round rotation constants */
R_512_0_0 = 46, R_512_0_1 = 36, R_512_0_2 = 19, R_512_0_3 = 37,
R_512_1_0 = 33, R_512_1_1 = 27, R_512_1_2 = 14, R_512_1_3 = 42,
R_512_2_0 = 17, R_512_2_1 = 49, R_512_2_2 = 36, R_512_2_3 = 39,
R_512_3_0 = 44, R_512_3_1 = 9, R_512_3_2 = 54, R_512_3_3 = 56,
R_512_4_0 = 39, R_512_4_1 = 30, R_512_4_2 = 34, R_512_4_3 = 24,
R_512_5_0 = 13, R_512_5_1 = 50, R_512_5_2 = 10, R_512_5_3 = 17,
R_512_6_0 = 25, R_512_6_1 = 29, R_512_6_2 = 39, R_512_6_3 = 43,
R_512_7_0 = 8, R_512_7_1 = 35, R_512_7_2 = 56, R_512_7_3 = 22,
/* Skein1024 round rotation constants */
R1024_0_0 = 24, R1024_0_1 = 13, R1024_0_2 = 8, R1024_0_3 = 47, R1024_0_4 = 8, R1024_0_5 = 17, R1024_0_6 = 22, R1024_0_7 = 37,
R1024_1_0 = 38, R1024_1_1 = 19, R1024_1_2 = 10, R1024_1_3 = 55, R1024_1_4 = 49, R1024_1_5 = 18, R1024_1_6 = 23, R1024_1_7 = 52,
R1024_2_0 = 33, R1024_2_1 = 4, R1024_2_2 = 51, R1024_2_3 = 13, R1024_2_4 = 34, R1024_2_5 = 41, R1024_2_6 = 59, R1024_2_7 = 17,
R1024_3_0 = 5, R1024_3_1 = 20, R1024_3_2 = 48, R1024_3_3 = 41, R1024_3_4 = 47, R1024_3_5 = 28, R1024_3_6 = 16, R1024_3_7 = 25,
R1024_4_0 = 41, R1024_4_1 = 9, R1024_4_2 = 37, R1024_4_3 = 31, R1024_4_4 = 12, R1024_4_5 = 47, R1024_4_6 = 44, R1024_4_7 = 30,
R1024_5_0 = 16, R1024_5_1 = 34, R1024_5_2 = 56, R1024_5_3 = 51, R1024_5_4 = 4, R1024_5_5 = 53, R1024_5_6 = 42, R1024_5_7 = 41,
R1024_6_0 = 31, R1024_6_1 = 44, R1024_6_2 = 47, R1024_6_3 = 46, R1024_6_4 = 19, R1024_6_5 = 42, R1024_6_6 = 44, R1024_6_7 = 25,
R1024_7_0 = 9, R1024_7_1 = 48, R1024_7_2 = 35, R1024_7_3 = 52, R1024_7_4 = 23, R1024_7_5 = 31, R1024_7_6 = 37, R1024_7_7 = 20
};
#ifndef SKEIN_ROUNDS
#define SKEIN_256_ROUNDS_TOTAL (72) /* number of rounds for the different block sizes */
#define SKEIN_512_ROUNDS_TOTAL (72)
#define SKEIN1024_ROUNDS_TOTAL (80)
#else /* allow command-line define in range 8*(5..14) */
#define SKEIN_256_ROUNDS_TOTAL (8*((((SKEIN_ROUNDS/100) + 5) % 10) + 5))
#define SKEIN_512_ROUNDS_TOTAL (8*((((SKEIN_ROUNDS/10) + 5) % 10) + 5))
#define SKEIN1024_ROUNDS_TOTAL (8*((((SKEIN_ROUNDS) + 5) % 10) + 5))
#endif
#endif /* ifndef _SKEIN_H_ */
