1 #ifndef _SKEIN_H_
2 #define _SKEIN_H_ 1
3 /**************************************************************************
4 **
5 ** Interface declarations and internal definitions for Skein hashing.
6 **
7 ** Source code author: Doug Whiting, 2008.
8 **
9 ** This algorithm and source code is released to the public domain.
10 **
11 ***************************************************************************
12 **
13 ** The following compile-time switches may be defined to control some
14 ** tradeoffs between speed, code size, error checking, and security.
15 **
16 ** The "default" note explains what happens when the switch is not defined.
17 **
18 ** SKEIN_ERR_CHECK -- how error checking is handled inside Skein
19 ** code. If not defined, most error checking
20 ** is disabled (for performance). Otherwise,
21 ** the switch value is interpreted as:
22 ** 0: use assert() to flag errors
23 ** 1: return SKEIN_FAIL to flag errors
24 **
25 ***************************************************************************/
26
27 /*Skein digest sizes for crypto api*/
28 #define SKEIN256_DIGEST_BIT_SIZE 256
29 #define SKEIN512_DIGEST_BIT_SIZE 512
30 #define SKEIN1024_DIGEST_BIT_SIZE 1024
31
32 /* below two prototype assume we are handed aligned data */
33 #define skein_put64_lsb_first(dst08, src64, b_cnt) memcpy(dst08, src64, b_cnt)
34 #define skein_get64_lsb_first(dst64, src08, w_cnt) \
35 memcpy(dst64, src08, 8*(w_cnt))
36 #define skein_swap64(w64) (w64)
37
38 enum {
39 SKEIN_SUCCESS = 0, /* return codes from Skein calls */
40 SKEIN_FAIL = 1,
41 SKEIN_BAD_HASHLEN = 2
42 };
43
44 #define SKEIN_MODIFIER_WORDS 2 /* number of modifier (tweak) words */
45
46 #define SKEIN_256_STATE_WORDS 4
47 #define SKEIN_512_STATE_WORDS 8
48 #define SKEIN_1024_STATE_WORDS 16
49 #define SKEIN_MAX_STATE_WORDS 16
50
51 #define SKEIN_256_STATE_BYTES (8*SKEIN_256_STATE_WORDS)
52 #define SKEIN_512_STATE_BYTES (8*SKEIN_512_STATE_WORDS)
53 #define SKEIN_1024_STATE_BYTES (8*SKEIN_1024_STATE_WORDS)
54
55 #define SKEIN_256_STATE_BITS (64*SKEIN_256_STATE_WORDS)
56 #define SKEIN_512_STATE_BITS (64*SKEIN_512_STATE_WORDS)
57 #define SKEIN_1024_STATE_BITS (64*SKEIN_1024_STATE_WORDS)
58
59 #define SKEIN_256_BLOCK_BYTES (8*SKEIN_256_STATE_WORDS)
60 #define SKEIN_512_BLOCK_BYTES (8*SKEIN_512_STATE_WORDS)
61 #define SKEIN_1024_BLOCK_BYTES (8*SKEIN_1024_STATE_WORDS)
62
63 struct skein_ctx_hdr {
64 size_t hash_bit_len; /* size of hash result, in bits */
65 size_t b_cnt; /* current byte count in buffer b[] */
66 u64 tweak[SKEIN_MODIFIER_WORDS]; /* tweak[0]=byte cnt, tweak[1]=flags */
67 };
68
69 struct skein_256_ctx { /* 256-bit Skein hash context structure */
70 struct skein_ctx_hdr h; /* common header context variables */
71 u64 x[SKEIN_256_STATE_WORDS]; /* chaining variables */
72 u8 b[SKEIN_256_BLOCK_BYTES]; /* partial block buf (8-byte aligned) */
73 };
74
75 struct skein_512_ctx { /* 512-bit Skein hash context structure */
76 struct skein_ctx_hdr h; /* common header context variables */
77 u64 x[SKEIN_512_STATE_WORDS]; /* chaining variables */
78 u8 b[SKEIN_512_BLOCK_BYTES]; /* partial block buf (8-byte aligned) */
79 };
80
81 struct skein_1024_ctx { /* 1024-bit Skein hash context structure */
82 struct skein_ctx_hdr h; /* common header context variables */
83 u64 x[SKEIN_1024_STATE_WORDS]; /* chaining variables */
84 u8 b[SKEIN_1024_BLOCK_BYTES]; /* partial block buf (8-byte aligned) */
85 };
86
rotl_64(u64 x,u8 N)87 static inline u64 rotl_64(u64 x, u8 N)
88 {
89 return (x << N) | (x >> (64 - N));
90 }
91
92 /* Skein APIs for (incremental) "straight hashing" */
93 int skein_256_init(struct skein_256_ctx *ctx, size_t hash_bit_len);
94 int skein_512_init(struct skein_512_ctx *ctx, size_t hash_bit_len);
95 int skein_1024_init(struct skein_1024_ctx *ctx, size_t hash_bit_len);
96
97 int skein_256_update(struct skein_256_ctx *ctx, const u8 *msg,
98 size_t msg_byte_cnt);
99 int skein_512_update(struct skein_512_ctx *ctx, const u8 *msg,
100 size_t msg_byte_cnt);
101 int skein_1024_update(struct skein_1024_ctx *ctx, const u8 *msg,
102 size_t msg_byte_cnt);
103
104 int skein_256_final(struct skein_256_ctx *ctx, u8 *hash_val);
105 int skein_512_final(struct skein_512_ctx *ctx, u8 *hash_val);
106 int skein_1024_final(struct skein_1024_ctx *ctx, u8 *hash_val);
107
108 /*
109 ** Skein APIs for "extended" initialization: MAC keys, tree hashing.
110 ** After an init_ext() call, just use update/final calls as with init().
111 **
112 ** Notes: Same parameters as _init() calls, plus tree_info/key/key_bytes.
113 ** When key_bytes == 0 and tree_info == SKEIN_SEQUENTIAL,
114 ** the results of init_ext() are identical to calling init().
115 ** The function init() may be called once to "precompute" the IV for
116 ** a given hash_bit_len value, then by saving a copy of the context
117 ** the IV computation may be avoided in later calls.
118 ** Similarly, the function init_ext() may be called once per MAC key
119 ** to precompute the MAC IV, then a copy of the context saved and
120 ** reused for each new MAC computation.
121 **/
122 int skein_256_init_ext(struct skein_256_ctx *ctx, size_t hash_bit_len,
123 u64 tree_info, const u8 *key, size_t key_bytes);
124 int skein_512_init_ext(struct skein_512_ctx *ctx, size_t hash_bit_len,
125 u64 tree_info, const u8 *key, size_t key_bytes);
126 int skein_1024_init_ext(struct skein_1024_ctx *ctx, size_t hash_bit_len,
127 u64 tree_info, const u8 *key, size_t key_bytes);
128
129 /*
130 ** Skein APIs for MAC and tree hash:
131 ** final_pad: pad, do final block, but no OUTPUT type
132 ** output: do just the output stage
133 */
134 int skein_256_final_pad(struct skein_256_ctx *ctx, u8 *hash_val);
135 int skein_512_final_pad(struct skein_512_ctx *ctx, u8 *hash_val);
136 int skein_1024_final_pad(struct skein_1024_ctx *ctx, u8 *hash_val);
137
138 #ifndef SKEIN_TREE_HASH
139 #define SKEIN_TREE_HASH (1)
140 #endif
141 #if SKEIN_TREE_HASH
142 int skein_256_output(struct skein_256_ctx *ctx, u8 *hash_val);
143 int skein_512_output(struct skein_512_ctx *ctx, u8 *hash_val);
144 int skein_1024_output(struct skein_1024_ctx *ctx, u8 *hash_val);
145 #endif
146
147 /*****************************************************************
148 ** "Internal" Skein definitions
149 ** -- not needed for sequential hashing API, but will be
150 ** helpful for other uses of Skein (e.g., tree hash mode).
151 ** -- included here so that they can be shared between
152 ** reference and optimized code.
153 ******************************************************************/
154
155 /* tweak word tweak[1]: bit field starting positions */
156 #define SKEIN_T1_BIT(BIT) ((BIT) - 64) /* second word */
157
158 #define SKEIN_T1_POS_TREE_LVL SKEIN_T1_BIT(112) /* 112..118 hash tree level */
159 #define SKEIN_T1_POS_BIT_PAD SKEIN_T1_BIT(119) /* 119 part. final in byte */
160 #define SKEIN_T1_POS_BLK_TYPE SKEIN_T1_BIT(120) /* 120..125 type field `*/
161 #define SKEIN_T1_POS_FIRST SKEIN_T1_BIT(126) /* 126 first blk flag */
162 #define SKEIN_T1_POS_FINAL SKEIN_T1_BIT(127) /* 127 final blk flag */
163
164 /* tweak word tweak[1]: flag bit definition(s) */
165 #define SKEIN_T1_FLAG_FIRST (((u64) 1) << SKEIN_T1_POS_FIRST)
166 #define SKEIN_T1_FLAG_FINAL (((u64) 1) << SKEIN_T1_POS_FINAL)
167 #define SKEIN_T1_FLAG_BIT_PAD (((u64) 1) << SKEIN_T1_POS_BIT_PAD)
168
169 /* tweak word tweak[1]: tree level bit field mask */
170 #define SKEIN_T1_TREE_LVL_MASK (((u64)0x7F) << SKEIN_T1_POS_TREE_LVL)
171 #define SKEIN_T1_TREE_LEVEL(n) (((u64) (n)) << SKEIN_T1_POS_TREE_LVL)
172
173 /* tweak word tweak[1]: block type field */
174 #define SKEIN_BLK_TYPE_KEY (0) /* key, for MAC and KDF */
175 #define SKEIN_BLK_TYPE_CFG (4) /* configuration block */
176 #define SKEIN_BLK_TYPE_PERS (8) /* personalization string */
177 #define SKEIN_BLK_TYPE_PK (12) /* pubkey (for digital sigs) */
178 #define SKEIN_BLK_TYPE_KDF (16) /* key identifier for KDF */
179 #define SKEIN_BLK_TYPE_NONCE (20) /* nonce for PRNG */
180 #define SKEIN_BLK_TYPE_MSG (48) /* message processing */
181 #define SKEIN_BLK_TYPE_OUT (63) /* output stage */
182 #define SKEIN_BLK_TYPE_MASK (63) /* bit field mask */
183
184 #define SKEIN_T1_BLK_TYPE(T) (((u64) (SKEIN_BLK_TYPE_##T)) << \
185 SKEIN_T1_POS_BLK_TYPE)
186 #define SKEIN_T1_BLK_TYPE_KEY SKEIN_T1_BLK_TYPE(KEY) /* for MAC and KDF */
187 #define SKEIN_T1_BLK_TYPE_CFG SKEIN_T1_BLK_TYPE(CFG) /* config block */
188 #define SKEIN_T1_BLK_TYPE_PERS SKEIN_T1_BLK_TYPE(PERS) /* personalization */
189 #define SKEIN_T1_BLK_TYPE_PK SKEIN_T1_BLK_TYPE(PK) /* pubkey (for sigs) */
190 #define SKEIN_T1_BLK_TYPE_KDF SKEIN_T1_BLK_TYPE(KDF) /* key ident for KDF */
191 #define SKEIN_T1_BLK_TYPE_NONCE SKEIN_T1_BLK_TYPE(NONCE)/* nonce for PRNG */
192 #define SKEIN_T1_BLK_TYPE_MSG SKEIN_T1_BLK_TYPE(MSG) /* message processing */
193 #define SKEIN_T1_BLK_TYPE_OUT SKEIN_T1_BLK_TYPE(OUT) /* output stage */
194 #define SKEIN_T1_BLK_TYPE_MASK SKEIN_T1_BLK_TYPE(MASK) /* field bit mask */
195
196 #define SKEIN_T1_BLK_TYPE_CFG_FINAL (SKEIN_T1_BLK_TYPE_CFG | \
197 SKEIN_T1_FLAG_FINAL)
198 #define SKEIN_T1_BLK_TYPE_OUT_FINAL (SKEIN_T1_BLK_TYPE_OUT | \
199 SKEIN_T1_FLAG_FINAL)
200
201 #define SKEIN_VERSION (1)
202
203 #ifndef SKEIN_ID_STRING_LE /* allow compile-time personalization */
204 #define SKEIN_ID_STRING_LE (0x33414853) /* "SHA3" (little-endian)*/
205 #endif
206
207 #define SKEIN_MK_64(hi32, lo32) ((lo32) + (((u64) (hi32)) << 32))
208 #define SKEIN_SCHEMA_VER SKEIN_MK_64(SKEIN_VERSION, SKEIN_ID_STRING_LE)
209 #define SKEIN_KS_PARITY SKEIN_MK_64(0x1BD11BDA, 0xA9FC1A22)
210
211 #define SKEIN_CFG_STR_LEN (4*8)
212
213 /* bit field definitions in config block tree_info word */
214 #define SKEIN_CFG_TREE_LEAF_SIZE_POS (0)
215 #define SKEIN_CFG_TREE_NODE_SIZE_POS (8)
216 #define SKEIN_CFG_TREE_MAX_LEVEL_POS (16)
217
218 #define SKEIN_CFG_TREE_LEAF_SIZE_MSK (((u64)0xFF) << \
219 SKEIN_CFG_TREE_LEAF_SIZE_POS)
220 #define SKEIN_CFG_TREE_NODE_SIZE_MSK (((u64)0xFF) << \
221 SKEIN_CFG_TREE_NODE_SIZE_POS)
222 #define SKEIN_CFG_TREE_MAX_LEVEL_MSK (((u64)0xFF) << \
223 SKEIN_CFG_TREE_MAX_LEVEL_POS)
224
225 #define SKEIN_CFG_TREE_INFO(leaf, node, max_lvl) \
226 ((((u64)(leaf)) << SKEIN_CFG_TREE_LEAF_SIZE_POS) | \
227 (((u64)(node)) << SKEIN_CFG_TREE_NODE_SIZE_POS) | \
228 (((u64)(max_lvl)) << SKEIN_CFG_TREE_MAX_LEVEL_POS))
229
230 /* use as tree_info in InitExt() call for sequential processing */
231 #define SKEIN_CFG_TREE_INFO_SEQUENTIAL SKEIN_CFG_TREE_INFO(0, 0, 0)
232
233 /*
234 ** Skein macros for getting/setting tweak words, etc.
235 ** These are useful for partial input bytes, hash tree init/update, etc.
236 **/
237 #define skein_get_tweak(ctx_ptr, TWK_NUM) ((ctx_ptr)->h.tweak[TWK_NUM])
238 #define skein_set_tweak(ctx_ptr, TWK_NUM, t_val) { \
239 (ctx_ptr)->h.tweak[TWK_NUM] = (t_val); \
240 }
241
242 #define skein_get_T0(ctx_ptr) skein_get_tweak(ctx_ptr, 0)
243 #define skein_get_T1(ctx_ptr) skein_get_tweak(ctx_ptr, 1)
244 #define skein_set_T0(ctx_ptr, T0) skein_set_tweak(ctx_ptr, 0, T0)
245 #define skein_set_T1(ctx_ptr, T1) skein_set_tweak(ctx_ptr, 1, T1)
246
247 /* set both tweak words at once */
248 #define skein_set_T0_T1(ctx_ptr, T0, T1) \
249 { \
250 skein_set_T0(ctx_ptr, (T0)); \
251 skein_set_T1(ctx_ptr, (T1)); \
252 }
253
254 #define skein_set_type(ctx_ptr, BLK_TYPE) \
255 skein_set_T1(ctx_ptr, SKEIN_T1_BLK_TYPE_##BLK_TYPE)
256
257 /*
258 * setup for starting with a new type:
259 * h.tweak[0]=0; h.tweak[1] = NEW_TYPE; h.b_cnt=0;
260 */
261 #define skein_start_new_type(ctx_ptr, BLK_TYPE) { \
262 skein_set_T0_T1(ctx_ptr, 0, SKEIN_T1_FLAG_FIRST | \
263 SKEIN_T1_BLK_TYPE_##BLK_TYPE); \
264 (ctx_ptr)->h.b_cnt = 0; \
265 }
266
267 #define skein_clear_first_flag(hdr) { \
268 (hdr).tweak[1] &= ~SKEIN_T1_FLAG_FIRST; \
269 }
270 #define skein_set_bit_pad_flag(hdr) { \
271 (hdr).tweak[1] |= SKEIN_T1_FLAG_BIT_PAD; \
272 }
273
274 #define skein_set_tree_level(hdr, height) { \
275 (hdr).tweak[1] |= SKEIN_T1_TREE_LEVEL(height); \
276 }
277
278 /* ignore all asserts, for performance */
279 #define skein_assert_ret(x, ret_code)
280 #define skein_assert(x)
281
282 /*****************************************************************
283 ** Skein block function constants (shared across Ref and Opt code)
284 ******************************************************************/
285 enum {
286 /* SKEIN_256 round rotation constants */
287 R_256_0_0 = 14, R_256_0_1 = 16,
288 R_256_1_0 = 52, R_256_1_1 = 57,
289 R_256_2_0 = 23, R_256_2_1 = 40,
290 R_256_3_0 = 5, R_256_3_1 = 37,
291 R_256_4_0 = 25, R_256_4_1 = 33,
292 R_256_5_0 = 46, R_256_5_1 = 12,
293 R_256_6_0 = 58, R_256_6_1 = 22,
294 R_256_7_0 = 32, R_256_7_1 = 32,
295
296 /* SKEIN_512 round rotation constants */
297 R_512_0_0 = 46, R_512_0_1 = 36, R_512_0_2 = 19, R_512_0_3 = 37,
298 R_512_1_0 = 33, R_512_1_1 = 27, R_512_1_2 = 14, R_512_1_3 = 42,
299 R_512_2_0 = 17, R_512_2_1 = 49, R_512_2_2 = 36, R_512_2_3 = 39,
300 R_512_3_0 = 44, R_512_3_1 = 9, R_512_3_2 = 54, R_512_3_3 = 56,
301 R_512_4_0 = 39, R_512_4_1 = 30, R_512_4_2 = 34, R_512_4_3 = 24,
302 R_512_5_0 = 13, R_512_5_1 = 50, R_512_5_2 = 10, R_512_5_3 = 17,
303 R_512_6_0 = 25, R_512_6_1 = 29, R_512_6_2 = 39, R_512_6_3 = 43,
304 R_512_7_0 = 8, R_512_7_1 = 35, R_512_7_2 = 56, R_512_7_3 = 22,
305
306 /* SKEIN_1024 round rotation constants */
307 R1024_0_0 = 24, R1024_0_1 = 13, R1024_0_2 = 8, R1024_0_3 = 47,
308 R1024_0_4 = 8, R1024_0_5 = 17, R1024_0_6 = 22, R1024_0_7 = 37,
309 R1024_1_0 = 38, R1024_1_1 = 19, R1024_1_2 = 10, R1024_1_3 = 55,
310 R1024_1_4 = 49, R1024_1_5 = 18, R1024_1_6 = 23, R1024_1_7 = 52,
311 R1024_2_0 = 33, R1024_2_1 = 4, R1024_2_2 = 51, R1024_2_3 = 13,
312 R1024_2_4 = 34, R1024_2_5 = 41, R1024_2_6 = 59, R1024_2_7 = 17,
313 R1024_3_0 = 5, R1024_3_1 = 20, R1024_3_2 = 48, R1024_3_3 = 41,
314 R1024_3_4 = 47, R1024_3_5 = 28, R1024_3_6 = 16, R1024_3_7 = 25,
315 R1024_4_0 = 41, R1024_4_1 = 9, R1024_4_2 = 37, R1024_4_3 = 31,
316 R1024_4_4 = 12, R1024_4_5 = 47, R1024_4_6 = 44, R1024_4_7 = 30,
317 R1024_5_0 = 16, R1024_5_1 = 34, R1024_5_2 = 56, R1024_5_3 = 51,
318 R1024_5_4 = 4, R1024_5_5 = 53, R1024_5_6 = 42, R1024_5_7 = 41,
319 R1024_6_0 = 31, R1024_6_1 = 44, R1024_6_2 = 47, R1024_6_3 = 46,
320 R1024_6_4 = 19, R1024_6_5 = 42, R1024_6_6 = 44, R1024_6_7 = 25,
321 R1024_7_0 = 9, R1024_7_1 = 48, R1024_7_2 = 35, R1024_7_3 = 52,
322 R1024_7_4 = 23, R1024_7_5 = 31, R1024_7_6 = 37, R1024_7_7 = 20
323 };
324
325 #ifndef SKEIN_ROUNDS
326 #define SKEIN_256_ROUNDS_TOTAL (72) /* # rounds for diff block sizes */
327 #define SKEIN_512_ROUNDS_TOTAL (72)
328 #define SKEIN_1024_ROUNDS_TOTAL (80)
329 #else /* allow command-line define in range 8*(5..14) */
330 #define SKEIN_256_ROUNDS_TOTAL (8*((((SKEIN_ROUNDS/100) + 5) % 10) + 5))
331 #define SKEIN_512_ROUNDS_TOTAL (8*((((SKEIN_ROUNDS/10) + 5) % 10) + 5))
332 #define SKEIN_1024_ROUNDS_TOTAL (8*((((SKEIN_ROUNDS) + 5) % 10) + 5))
333 #endif
334
335 #endif /* ifndef _SKEIN_H_ */
336