summaryrefslogtreecommitdiff
path: root/drivers/crypto/chelsio/chcr_algo.h
blob: 54851ecaa6c162448961bcee14775f4eb9aea826 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
/*
 * This file is part of the Chelsio T6 Crypto driver for Linux.
 *
 * Copyright (c) 2003-2016 Chelsio Communications, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

#ifndef __CHCR_ALGO_H__
#define __CHCR_ALGO_H__

/* Crypto key context */
#define KEY_CONTEXT_CTX_LEN_S           24
#define KEY_CONTEXT_CTX_LEN_M           0xff
#define KEY_CONTEXT_CTX_LEN_V(x)        ((x) << KEY_CONTEXT_CTX_LEN_S)
#define KEY_CONTEXT_CTX_LEN_G(x) \
	(((x) >> KEY_CONTEXT_CTX_LEN_S) & KEY_CONTEXT_CTX_LEN_M)

#define KEY_CONTEXT_DUAL_CK_S      12
#define KEY_CONTEXT_DUAL_CK_M      0x1
#define KEY_CONTEXT_DUAL_CK_V(x)   ((x) << KEY_CONTEXT_DUAL_CK_S)
#define KEY_CONTEXT_DUAL_CK_G(x)   \
(((x) >> KEY_CONTEXT_DUAL_CK_S) & KEY_CONTEXT_DUAL_CK_M)
#define KEY_CONTEXT_DUAL_CK_F      KEY_CONTEXT_DUAL_CK_V(1U)

#define KEY_CONTEXT_SALT_PRESENT_S      10
#define KEY_CONTEXT_SALT_PRESENT_M      0x1
#define KEY_CONTEXT_SALT_PRESENT_V(x)   ((x) << KEY_CONTEXT_SALT_PRESENT_S)
#define KEY_CONTEXT_SALT_PRESENT_G(x)   \
	(((x) >> KEY_CONTEXT_SALT_PRESENT_S) & \
	 KEY_CONTEXT_SALT_PRESENT_M)
#define KEY_CONTEXT_SALT_PRESENT_F      KEY_CONTEXT_SALT_PRESENT_V(1U)

#define KEY_CONTEXT_VALID_S     0
#define KEY_CONTEXT_VALID_M     0x1
#define KEY_CONTEXT_VALID_V(x)  ((x) << KEY_CONTEXT_VALID_S)
#define KEY_CONTEXT_VALID_G(x)  \
	(((x) >> KEY_CONTEXT_VALID_S) & \
	 KEY_CONTEXT_VALID_M)
#define KEY_CONTEXT_VALID_F     KEY_CONTEXT_VALID_V(1U)

#define KEY_CONTEXT_CK_SIZE_S           6
#define KEY_CONTEXT_CK_SIZE_M           0xf
#define KEY_CONTEXT_CK_SIZE_V(x)        ((x) << KEY_CONTEXT_CK_SIZE_S)
#define KEY_CONTEXT_CK_SIZE_G(x)        \
	(((x) >> KEY_CONTEXT_CK_SIZE_S) & KEY_CONTEXT_CK_SIZE_M)

#define KEY_CONTEXT_MK_SIZE_S           2
#define KEY_CONTEXT_MK_SIZE_M           0xf
#define KEY_CONTEXT_MK_SIZE_V(x)        ((x) << KEY_CONTEXT_MK_SIZE_S)
#define KEY_CONTEXT_MK_SIZE_G(x)        \
	(((x) >> KEY_CONTEXT_MK_SIZE_S) & KEY_CONTEXT_MK_SIZE_M)

#define KEY_CONTEXT_OPAD_PRESENT_S      11
#define KEY_CONTEXT_OPAD_PRESENT_M      0x1
#define KEY_CONTEXT_OPAD_PRESENT_V(x)   ((x) << KEY_CONTEXT_OPAD_PRESENT_S)
#define KEY_CONTEXT_OPAD_PRESENT_G(x)   \
	(((x) >> KEY_CONTEXT_OPAD_PRESENT_S) & \
	 KEY_CONTEXT_OPAD_PRESENT_M)
#define KEY_CONTEXT_OPAD_PRESENT_F      KEY_CONTEXT_OPAD_PRESENT_V(1U)

#define CHCR_HASH_MAX_DIGEST_SIZE 64
#define CHCR_MAX_SHA_DIGEST_SIZE 64

#define IPSEC_TRUNCATED_ICV_SIZE 12
#define TLS_TRUNCATED_HMAC_SIZE 10
#define CBCMAC_DIGEST_SIZE 16
#define MAX_HASH_NAME 20

#define SHA1_INIT_STATE_5X4B    5
#define SHA256_INIT_STATE_8X4B  8
#define SHA512_INIT_STATE_8X8B  8
#define SHA1_INIT_STATE         SHA1_INIT_STATE_5X4B
#define SHA224_INIT_STATE       SHA256_INIT_STATE_8X4B
#define SHA256_INIT_STATE       SHA256_INIT_STATE_8X4B
#define SHA384_INIT_STATE       SHA512_INIT_STATE_8X8B
#define SHA512_INIT_STATE       SHA512_INIT_STATE_8X8B

#define DUMMY_BYTES 16

#define IPAD_DATA 0x36363636
#define OPAD_DATA 0x5c5c5c5c

#define TRANSHDR_SIZE(kctx_len)\
	(sizeof(struct chcr_wr) +\
	 kctx_len)
#define CIPHER_TRANSHDR_SIZE(kctx_len, sge_pairs) \
	(TRANSHDR_SIZE((kctx_len)) + (sge_pairs) +\
	 sizeof(struct cpl_rx_phys_dsgl))
#define HASH_TRANSHDR_SIZE(kctx_len)\
	(TRANSHDR_SIZE(kctx_len) + DUMMY_BYTES)


#define FILL_SEC_CPL_OP_IVINSR(id, len, ofst)      \
	htonl( \
	       CPL_TX_SEC_PDU_OPCODE_V(CPL_TX_SEC_PDU) | \
	       CPL_TX_SEC_PDU_RXCHID_V((id)) | \
	       CPL_TX_SEC_PDU_ACKFOLLOWS_V(0) | \
	       CPL_TX_SEC_PDU_ULPTXLPBK_V(1) | \
	       CPL_TX_SEC_PDU_CPLLEN_V((len)) | \
	       CPL_TX_SEC_PDU_PLACEHOLDER_V(0) | \
	       CPL_TX_SEC_PDU_IVINSRTOFST_V((ofst)))

#define  FILL_SEC_CPL_CIPHERSTOP_HI(a_start, a_stop, c_start, c_stop_hi) \
	htonl( \
	       CPL_TX_SEC_PDU_AADSTART_V((a_start)) | \
	       CPL_TX_SEC_PDU_AADSTOP_V((a_stop)) | \
	       CPL_TX_SEC_PDU_CIPHERSTART_V((c_start)) | \
	       CPL_TX_SEC_PDU_CIPHERSTOP_HI_V((c_stop_hi)))

#define  FILL_SEC_CPL_AUTHINSERT(c_stop_lo, a_start, a_stop, a_inst) \
	htonl( \
	       CPL_TX_SEC_PDU_CIPHERSTOP_LO_V((c_stop_lo)) | \
		CPL_TX_SEC_PDU_AUTHSTART_V((a_start)) | \
		CPL_TX_SEC_PDU_AUTHSTOP_V((a_stop)) | \
		CPL_TX_SEC_PDU_AUTHINSERT_V((a_inst)))

#define  FILL_SEC_CPL_SCMD0_SEQNO(ctrl, seq, cmode, amode, opad, size)  \
		htonl( \
		SCMD_SEQ_NO_CTRL_V(0) | \
		SCMD_STATUS_PRESENT_V(0) | \
		SCMD_PROTO_VERSION_V(CHCR_SCMD_PROTO_VERSION_GENERIC) | \
		SCMD_ENC_DEC_CTRL_V((ctrl)) | \
		SCMD_CIPH_AUTH_SEQ_CTRL_V((seq)) | \
		SCMD_CIPH_MODE_V((cmode)) | \
		SCMD_AUTH_MODE_V((amode)) | \
		SCMD_HMAC_CTRL_V((opad)) | \
		SCMD_IV_SIZE_V((size)) | \
		SCMD_NUM_IVS_V(0))

#define FILL_SEC_CPL_IVGEN_HDRLEN(last, more, ctx_in, mac, ivdrop, len) htonl( \
		SCMD_ENB_DBGID_V(0) | \
		SCMD_IV_GEN_CTRL_V(0) | \
		SCMD_LAST_FRAG_V((last)) | \
		SCMD_MORE_FRAGS_V((more)) | \
		SCMD_TLS_COMPPDU_V(0) | \
		SCMD_KEY_CTX_INLINE_V((ctx_in)) | \
		SCMD_TLS_FRAG_ENABLE_V(0) | \
		SCMD_MAC_ONLY_V((mac)) |  \
		SCMD_AADIVDROP_V((ivdrop)) | \
		SCMD_HDR_LEN_V((len)))

#define  FILL_KEY_CTX_HDR(ck_size, mk_size, d_ck, opad, ctx_len) \
		htonl(KEY_CONTEXT_VALID_V(1) | \
		      KEY_CONTEXT_CK_SIZE_V((ck_size)) | \
		      KEY_CONTEXT_MK_SIZE_V(mk_size) | \
		      KEY_CONTEXT_DUAL_CK_V((d_ck)) | \
		      KEY_CONTEXT_OPAD_PRESENT_V((opad)) | \
		      KEY_CONTEXT_SALT_PRESENT_V(1) | \
		      KEY_CONTEXT_CTX_LEN_V((ctx_len)))

#define FILL_WR_OP_CCTX_SIZE \
		htonl( \
			FW_CRYPTO_LOOKASIDE_WR_OPCODE_V( \
			FW_CRYPTO_LOOKASIDE_WR) | \
			FW_CRYPTO_LOOKASIDE_WR_COMPL_V(0) | \
			FW_CRYPTO_LOOKASIDE_WR_IMM_LEN_V((0)) | \
			FW_CRYPTO_LOOKASIDE_WR_CCTX_LOC_V(0) | \
			FW_CRYPTO_LOOKASIDE_WR_CCTX_SIZE_V(0))

#define FILL_WR_RX_Q_ID(cid, qid, lcb, fid) \
		htonl( \
			FW_CRYPTO_LOOKASIDE_WR_RX_CHID_V((cid)) | \
			FW_CRYPTO_LOOKASIDE_WR_RX_Q_ID_V((qid)) | \
			FW_CRYPTO_LOOKASIDE_WR_LCB_V((lcb)) | \
			FW_CRYPTO_LOOKASIDE_WR_IV_V((IV_NOP)) | \
			FW_CRYPTO_LOOKASIDE_WR_FQIDX_V(fid))

#define FILL_ULPTX_CMD_DEST(cid, qid) \
	htonl(ULPTX_CMD_V(ULP_TX_PKT) | \
	      ULP_TXPKT_DEST_V(0) | \
	      ULP_TXPKT_DATAMODIFY_V(0) | \
	      ULP_TXPKT_CHANNELID_V((cid)) | \
	      ULP_TXPKT_RO_V(1) | \
	      ULP_TXPKT_FID_V(qid))

#define KEYCTX_ALIGN_PAD(bs) ({unsigned int _bs = (bs);\
			      _bs == SHA1_DIGEST_SIZE ? 12 : 0; })

#define FILL_PLD_SIZE_HASH_SIZE(payload_sgl_len, sgl_lengths, total_frags) \
	htonl(FW_CRYPTO_LOOKASIDE_WR_PLD_SIZE_V(payload_sgl_len ? \
						sgl_lengths[total_frags] : 0) |\
	      FW_CRYPTO_LOOKASIDE_WR_HASH_SIZE_V(0))

#define FILL_LEN_PKD(calc_tx_flits_ofld, skb) \
	htonl(FW_CRYPTO_LOOKASIDE_WR_LEN16_V(DIV_ROUND_UP((\
					   calc_tx_flits_ofld(skb) * 8), 16)))

#define FILL_CMD_MORE(immdatalen) htonl(ULPTX_CMD_V(ULP_TX_SC_IMM) |\
					ULP_TX_SC_MORE_V((immdatalen) ? 0 : 1))

#define MAX_NK 8
#define CRYPTO_MAX_IMM_TX_PKT_LEN 256
#define MAX_WR_SIZE			512
#define ROUND_16(bytes)		((bytes) & 0xFFFFFFF0)
#define MAX_DSGL_ENT			32
#define MAX_DIGEST_SKB_SGE	(MAX_SKB_FRAGS - 2)
#define MIN_CIPHER_SG			1 /* IV */
#define MIN_AUTH_SG			2 /*IV + AAD*/
#define MIN_GCM_SG			2 /* IV + AAD*/
#define MIN_DIGEST_SG			1 /*Partial Buffer*/
#define MIN_CCM_SG			3 /*IV+AAD+B0*/
#define SPACE_LEFT(len) \
	((MAX_WR_SIZE - WR_MIN_LEN - (len)))

unsigned int sgl_ent_len[] = {0, 0, 16, 24, 40,
				48, 64, 72, 88,
				96, 112, 120, 136,
				144, 160, 168, 184,
				192};
unsigned int dsgl_ent_len[] = {0, 32, 32, 48, 48, 64, 64, 80, 80,
				112, 112, 128, 128, 144, 144, 160, 160,
				192, 192, 208, 208, 224, 224, 240, 240,
				272, 272, 288, 288, 304, 304, 320, 320};

struct algo_param {
	unsigned int auth_mode;
	unsigned int mk_size;
	unsigned int result_size;
};

struct hash_wr_param {
	unsigned int opad_needed;
	unsigned int more;
	unsigned int last;
	struct algo_param alg_prm;
	unsigned int sg_len;
	unsigned int bfr_len;
	u64 scmd1;
};

struct cipher_wr_param {
	struct ablkcipher_request *req;
	struct scatterlist *srcsg;
	char *iv;
	int bytes;
	short int snent;
	unsigned short qid;
};
enum {
	AES_KEYLENGTH_128BIT = 128,
	AES_KEYLENGTH_192BIT = 192,
	AES_KEYLENGTH_256BIT = 256
};

enum {
	KEYLENGTH_3BYTES = 3,
	KEYLENGTH_4BYTES = 4,
	KEYLENGTH_6BYTES = 6,
	KEYLENGTH_8BYTES = 8
};

enum {
	NUMBER_OF_ROUNDS_10 = 10,
	NUMBER_OF_ROUNDS_12 = 12,
	NUMBER_OF_ROUNDS_14 = 14,
};

/*
 * CCM defines values of 4, 6, 8, 10, 12, 14, and 16 octets,
 * where they indicate the size of the integrity check value (ICV)
 */
enum {
	ICV_4  = 4,
	ICV_6  = 6,
	ICV_8  = 8,
	ICV_10 = 10,
	ICV_12 = 12,
	ICV_13 = 13,
	ICV_14 = 14,
	ICV_15 = 15,
	ICV_16 = 16
};

struct hash_op_params {
	unsigned char mk_size;
	unsigned char pad_align;
	unsigned char auth_mode;
	char hash_name[MAX_HASH_NAME];
	unsigned short block_size;
	unsigned short word_size;
	unsigned short ipad_size;
};

struct phys_sge_pairs {
	__be16 len[8];
	__be64 addr[8];
};

struct phys_sge_parm {
	unsigned int nents;
	unsigned int obsize;
	unsigned short qid;
};

struct crypto_result {
	struct completion completion;
	int err;
};

static const u32 sha1_init[SHA1_DIGEST_SIZE / 4] = {
		SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4,
};

static const u32 sha224_init[SHA256_DIGEST_SIZE / 4] = {
		SHA224_H0, SHA224_H1, SHA224_H2, SHA224_H3,
		SHA224_H4, SHA224_H5, SHA224_H6, SHA224_H7,
};

static const u32 sha256_init[SHA256_DIGEST_SIZE / 4] = {
		SHA256_H0, SHA256_H1, SHA256_H2, SHA256_H3,
		SHA256_H4, SHA256_H5, SHA256_H6, SHA256_H7,
};

static const u64 sha384_init[SHA512_DIGEST_SIZE / 8] = {
		SHA384_H0, SHA384_H1, SHA384_H2, SHA384_H3,
		SHA384_H4, SHA384_H5, SHA384_H6, SHA384_H7,
};

static const u64 sha512_init[SHA512_DIGEST_SIZE / 8] = {
		SHA512_H0, SHA512_H1, SHA512_H2, SHA512_H3,
		SHA512_H4, SHA512_H5, SHA512_H6, SHA512_H7,
};

static inline void copy_hash_init_values(char *key, int digestsize)
{
	u8 i;
	__be32 *dkey = (__be32 *)key;
	u64 *ldkey = (u64 *)key;
	__be64 *sha384 = (__be64 *)sha384_init;
	__be64 *sha512 = (__be64 *)sha512_init;

	switch (digestsize) {
	case SHA1_DIGEST_SIZE:
		for (i = 0; i < SHA1_INIT_STATE; i++)
			dkey[i] = cpu_to_be32(sha1_init[i]);
		break;
	case SHA224_DIGEST_SIZE:
		for (i = 0; i < SHA224_INIT_STATE; i++)
			dkey[i] = cpu_to_be32(sha224_init[i]);
		break;
	case SHA256_DIGEST_SIZE:
		for (i = 0; i < SHA256_INIT_STATE; i++)
			dkey[i] = cpu_to_be32(sha256_init[i]);
		break;
	case SHA384_DIGEST_SIZE:
		for (i = 0; i < SHA384_INIT_STATE; i++)
			ldkey[i] = be64_to_cpu(sha384[i]);
		break;
	case SHA512_DIGEST_SIZE:
		for (i = 0; i < SHA512_INIT_STATE; i++)
			ldkey[i] = be64_to_cpu(sha512[i]);
		break;
	}
}

static const u8 sgl_lengths[20] = {
	0, 1, 2, 3, 4, 4, 5, 6, 7, 7, 8, 9, 10, 10, 11, 12, 13, 13, 14, 15
};

/* Number of len fields(8) * size of one addr field */
#define PHYSDSGL_MAX_LEN_SIZE 16

static inline u16 get_space_for_phys_dsgl(unsigned int sgl_entr)
{
	/* len field size + addr field size */
	return ((sgl_entr >> 3) + ((sgl_entr % 8) ?
				   1 : 0)) * PHYSDSGL_MAX_LEN_SIZE +
		(sgl_entr << 3) + ((sgl_entr % 2 ? 1 : 0) << 3);
}

/* The AES s-transform matrix (s-box). */
static const u8 aes_sbox[256] = {
	99,  124, 119, 123, 242, 107, 111, 197, 48,  1,   103, 43,  254, 215,
	171, 118, 202, 130, 201, 125, 250, 89,  71,  240, 173, 212, 162, 175,
	156, 164, 114, 192, 183, 253, 147, 38,  54,  63,  247, 204, 52,  165,
	229, 241, 113, 216, 49,  21, 4,   199, 35,  195, 24,  150, 5, 154, 7,
	18,  128, 226, 235, 39,  178, 117, 9,   131, 44,  26,  27,  110, 90,
	160, 82,  59,  214, 179, 41,  227, 47,  132, 83,  209, 0,   237, 32,
	252, 177, 91,  106, 203, 190, 57,  74,  76,  88,  207, 208, 239, 170,
	251, 67,  77,  51,  133, 69,  249, 2,   127, 80,  60,  159, 168, 81,
	163, 64,  143, 146, 157, 56,  245, 188, 182, 218, 33,  16,  255, 243,
	210, 205, 12,  19,  236, 95,  151, 68,  23,  196, 167, 126, 61,  100,
	93,  25,  115, 96,  129, 79,  220, 34,  42,  144, 136, 70,  238, 184,
	20,  222, 94,  11,  219, 224, 50,  58,  10,  73,  6,   36,  92,  194,
	211, 172, 98,  145, 149, 228, 121, 231, 200, 55,  109, 141, 213, 78,
	169, 108, 86,  244, 234, 101, 122, 174, 8, 186, 120, 37,  46,  28, 166,
	180, 198, 232, 221, 116, 31,  75,  189, 139, 138, 112, 62,  181, 102,
	72,  3,   246, 14,  97,  53,  87,  185, 134, 193, 29,  158, 225, 248,
	152, 17,  105, 217, 142, 148, 155, 30,  135, 233, 206, 85,  40,  223,
	140, 161, 137, 13,  191, 230, 66,  104, 65,  153, 45,  15,  176, 84,
	187, 22
};

static inline u32 aes_ks_subword(const u32 w)
{
	u8 bytes[4];

	*(u32 *)(&bytes[0]) = w;
	bytes[0] = aes_sbox[bytes[0]];
	bytes[1] = aes_sbox[bytes[1]];
	bytes[2] = aes_sbox[bytes[2]];
	bytes[3] = aes_sbox[bytes[3]];
	return *(u32 *)(&bytes[0]);
}

static u32 round_constant[11] = {
	0x01000000, 0x02000000, 0x04000000, 0x08000000,
	0x10000000, 0x20000000, 0x40000000, 0x80000000,
	0x1B000000, 0x36000000, 0x6C000000
};

#endif /* __CHCR_ALGO_H__ */