xref: /openbmc/linux/drivers/crypto/bcm/cipher.h (revision e3b9f1e8)
1 /*
2  * Copyright 2016 Broadcom
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License, version 2, as
6  * published by the Free Software Foundation (the "GPL").
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License version 2 (GPLv2) for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * version 2 (GPLv2) along with this source code.
15  */
16 
17 #ifndef _CIPHER_H
18 #define _CIPHER_H
19 
20 #include <linux/atomic.h>
21 #include <linux/mailbox/brcm-message.h>
22 #include <linux/mailbox_client.h>
23 #include <crypto/aes.h>
24 #include <crypto/internal/hash.h>
25 #include <crypto/aead.h>
26 #include <crypto/gcm.h>
27 #include <crypto/sha.h>
28 #include <crypto/sha3.h>
29 
30 #include "spu.h"
31 #include "spum.h"
32 #include "spu2.h"
33 
34 /* Driver supports up to MAX_SPUS SPU blocks */
35 #define MAX_SPUS 16
36 
37 #define ARC4_MIN_KEY_SIZE   1
38 #define ARC4_MAX_KEY_SIZE   256
39 #define ARC4_BLOCK_SIZE     1
40 #define ARC4_STATE_SIZE     4
41 
42 #define CCM_AES_IV_SIZE    16
43 #define CCM_ESP_IV_SIZE     8
44 #define RFC4543_ICV_SIZE   16
45 
46 #define MAX_KEY_SIZE	ARC4_MAX_KEY_SIZE
47 #define MAX_IV_SIZE	AES_BLOCK_SIZE
48 #define MAX_DIGEST_SIZE	SHA3_512_DIGEST_SIZE
49 #define MAX_ASSOC_SIZE	512
50 
51 /* size of salt value for AES-GCM-ESP and AES-CCM-ESP */
52 #define GCM_ESP_SALT_SIZE   4
53 #define CCM_ESP_SALT_SIZE   3
54 #define MAX_SALT_SIZE       GCM_ESP_SALT_SIZE
55 #define GCM_ESP_SALT_OFFSET 0
56 #define CCM_ESP_SALT_OFFSET 1
57 
58 #define GCM_ESP_DIGESTSIZE 16
59 
60 #define MAX_HASH_BLOCK_SIZE SHA512_BLOCK_SIZE
61 
62 /*
63  * Maximum number of bytes from a non-final hash request that can be deferred
64  * until more data is available. With new crypto API framework, this
65  * can be no more than one block of data.
66  */
67 #define HASH_CARRY_MAX  MAX_HASH_BLOCK_SIZE
68 
69 /* Force at least 4-byte alignment of all SPU message fields */
70 #define SPU_MSG_ALIGN  4
71 
72 /* Number of times to resend mailbox message if mb queue is full */
73 #define SPU_MB_RETRY_MAX  1000
74 
75 /* op_counts[] indexes */
76 enum op_type {
77 	SPU_OP_CIPHER,
78 	SPU_OP_HASH,
79 	SPU_OP_HMAC,
80 	SPU_OP_AEAD,
81 	SPU_OP_NUM
82 };
83 
84 enum spu_spu_type {
85 	SPU_TYPE_SPUM,
86 	SPU_TYPE_SPU2,
87 };
88 
89 /*
90  * SPUM_NS2 and SPUM_NSP are the SPU-M block on Northstar 2 and Northstar Plus,
91  * respectively.
92  */
93 enum spu_spu_subtype {
94 	SPU_SUBTYPE_SPUM_NS2,
95 	SPU_SUBTYPE_SPUM_NSP,
96 	SPU_SUBTYPE_SPU2_V1,
97 	SPU_SUBTYPE_SPU2_V2
98 };
99 
100 struct spu_type_subtype {
101 	enum spu_spu_type type;
102 	enum spu_spu_subtype subtype;
103 };
104 
105 struct cipher_op {
106 	enum spu_cipher_alg alg;
107 	enum spu_cipher_mode mode;
108 };
109 
110 struct auth_op {
111 	enum hash_alg alg;
112 	enum hash_mode mode;
113 };
114 
115 struct iproc_alg_s {
116 	u32 type;
117 	union {
118 		struct crypto_alg crypto;
119 		struct ahash_alg hash;
120 		struct aead_alg aead;
121 	} alg;
122 	struct cipher_op cipher_info;
123 	struct auth_op auth_info;
124 	bool auth_first;
125 	bool registered;
126 };
127 
128 /*
129  * Buffers for a SPU request/reply message pair. All part of one structure to
130  * allow a single alloc per request.
131  */
132 struct spu_msg_buf {
133 	/* Request message fragments */
134 
135 	/*
136 	 * SPU request message header. For SPU-M, holds MH, EMH, SCTX, BDESC,
137 	 * and BD header. For SPU2, holds FMD, OMD.
138 	 */
139 	u8 bcm_spu_req_hdr[ALIGN(SPU2_HEADER_ALLOC_LEN, SPU_MSG_ALIGN)];
140 
141 	/* IV or counter. Size to include salt. Also used for XTS tweek. */
142 	u8 iv_ctr[ALIGN(2 * AES_BLOCK_SIZE, SPU_MSG_ALIGN)];
143 
144 	/* Hash digest. request and response. */
145 	u8 digest[ALIGN(MAX_DIGEST_SIZE, SPU_MSG_ALIGN)];
146 
147 	/* SPU request message padding */
148 	u8 spu_req_pad[ALIGN(SPU_PAD_LEN_MAX, SPU_MSG_ALIGN)];
149 
150 	/* SPU-M request message STATUS field */
151 	u8 tx_stat[ALIGN(SPU_TX_STATUS_LEN, SPU_MSG_ALIGN)];
152 
153 	/* Response message fragments */
154 
155 	/* SPU response message header */
156 	u8 spu_resp_hdr[ALIGN(SPU2_HEADER_ALLOC_LEN, SPU_MSG_ALIGN)];
157 
158 	/* SPU response message STATUS field padding */
159 	u8 rx_stat_pad[ALIGN(SPU_STAT_PAD_MAX, SPU_MSG_ALIGN)];
160 
161 	/* SPU response message STATUS field */
162 	u8 rx_stat[ALIGN(SPU_RX_STATUS_LEN, SPU_MSG_ALIGN)];
163 
164 	union {
165 		/* Buffers only used for ablkcipher */
166 		struct {
167 			/*
168 			 * Field used for either SUPDT when RC4 is used
169 			 * -OR- tweak value when XTS/AES is used
170 			 */
171 			u8 supdt_tweak[ALIGN(SPU_SUPDT_LEN, SPU_MSG_ALIGN)];
172 		} c;
173 
174 		/* Buffers only used for aead */
175 		struct {
176 			/* SPU response pad for GCM data */
177 			u8 gcmpad[ALIGN(AES_BLOCK_SIZE, SPU_MSG_ALIGN)];
178 
179 			/* SPU request msg padding for GCM AAD */
180 			u8 req_aad_pad[ALIGN(SPU_PAD_LEN_MAX, SPU_MSG_ALIGN)];
181 
182 			/* SPU response data to be discarded */
183 			u8 resp_aad[ALIGN(MAX_ASSOC_SIZE + MAX_IV_SIZE,
184 					  SPU_MSG_ALIGN)];
185 		} a;
186 	};
187 };
188 
189 struct iproc_ctx_s {
190 	u8 enckey[MAX_KEY_SIZE + ARC4_STATE_SIZE];
191 	unsigned int enckeylen;
192 
193 	u8 authkey[MAX_KEY_SIZE + ARC4_STATE_SIZE];
194 	unsigned int authkeylen;
195 
196 	u8 salt[MAX_SALT_SIZE];
197 	unsigned int salt_len;
198 	unsigned int salt_offset;
199 	u8 iv[MAX_IV_SIZE];
200 
201 	unsigned int digestsize;
202 
203 	struct iproc_alg_s *alg;
204 	bool is_esp;
205 
206 	struct cipher_op cipher;
207 	enum spu_cipher_type cipher_type;
208 
209 	struct auth_op auth;
210 	bool auth_first;
211 
212 	/*
213 	 * The maximum length in bytes of the payload in a SPU message for this
214 	 * context. For SPU-M, the payload is the combination of AAD and data.
215 	 * For SPU2, the payload is just data. A value of SPU_MAX_PAYLOAD_INF
216 	 * indicates that there is no limit to the length of the SPU message
217 	 * payload.
218 	 */
219 	unsigned int max_payload;
220 
221 	struct crypto_aead *fallback_cipher;
222 
223 	/* auth_type is determined during processing of request */
224 
225 	u8 ipad[MAX_HASH_BLOCK_SIZE];
226 	u8 opad[MAX_HASH_BLOCK_SIZE];
227 
228 	/*
229 	 * Buffer to hold SPU message header template. Template is created at
230 	 * setkey time for ablkcipher requests, since most of the fields in the
231 	 * header are known at that time. At request time, just fill in a few
232 	 * missing pieces related to length of data in the request and IVs, etc.
233 	 */
234 	u8 bcm_spu_req_hdr[ALIGN(SPU2_HEADER_ALLOC_LEN, SPU_MSG_ALIGN)];
235 
236 	/* Length of SPU request header */
237 	u16 spu_req_hdr_len;
238 
239 	/* Expected length of SPU response header */
240 	u16 spu_resp_hdr_len;
241 
242 	/*
243 	 * shash descriptor - needed to perform incremental hashing in
244 	 * in software, when hw doesn't support it.
245 	 */
246 	struct shash_desc *shash;
247 
248 	bool is_rfc4543;	/* RFC 4543 style of GMAC */
249 };
250 
251 /* state from iproc_reqctx_s necessary for hash state export/import */
252 struct spu_hash_export_s {
253 	unsigned int total_todo;
254 	unsigned int total_sent;
255 	u8 hash_carry[HASH_CARRY_MAX];
256 	unsigned int hash_carry_len;
257 	u8 incr_hash[MAX_DIGEST_SIZE];
258 	bool is_sw_hmac;
259 };
260 
261 struct iproc_reqctx_s {
262 	/* general context */
263 	struct crypto_async_request *parent;
264 
265 	/* only valid after enqueue() */
266 	struct iproc_ctx_s *ctx;
267 
268 	u8 chan_idx;   /* Mailbox channel to be used to submit this request */
269 
270 	/* total todo, rx'd, and sent for this request */
271 	unsigned int total_todo;
272 	unsigned int total_received;	/* only valid for ablkcipher */
273 	unsigned int total_sent;
274 
275 	/*
276 	 * num bytes sent to hw from the src sg in this request. This can differ
277 	 * from total_sent for incremental hashing. total_sent includes previous
278 	 * init() and update() data. src_sent does not.
279 	 */
280 	unsigned int src_sent;
281 
282 	/*
283 	 * For AEAD requests, start of associated data. This will typically
284 	 * point to the beginning of the src scatterlist from the request,
285 	 * since assoc data is at the beginning of the src scatterlist rather
286 	 * than in its own sg.
287 	 */
288 	struct scatterlist *assoc;
289 
290 	/*
291 	 * scatterlist entry and offset to start of data for next chunk. Crypto
292 	 * API src scatterlist for AEAD starts with AAD, if present. For first
293 	 * chunk, src_sg is sg entry at beginning of input data (after AAD).
294 	 * src_skip begins at the offset in that sg entry where data begins.
295 	 */
296 	struct scatterlist *src_sg;
297 	int src_nents;		/* Number of src entries with data */
298 	u32 src_skip;		/* bytes of current sg entry already used */
299 
300 	/*
301 	 * Same for destination. For AEAD, if there is AAD, output data must
302 	 * be written at offset following AAD.
303 	 */
304 	struct scatterlist *dst_sg;
305 	int dst_nents;		/* Number of dst entries with data */
306 	u32 dst_skip;		/* bytes of current sg entry already written */
307 
308 	/* Mailbox message used to send this request to PDC driver */
309 	struct brcm_message mb_mssg;
310 
311 	bool bd_suppress;	/* suppress BD field in SPU response? */
312 
313 	/* cipher context */
314 	bool is_encrypt;
315 
316 	/*
317 	 * CBC mode: IV.  CTR mode: counter.  Else empty. Used as a DMA
318 	 * buffer for AEAD requests. So allocate as DMAable memory. If IV
319 	 * concatenated with salt, includes the salt.
320 	 */
321 	u8 *iv_ctr;
322 	/* Length of IV or counter, in bytes */
323 	unsigned int iv_ctr_len;
324 
325 	/*
326 	 * Hash requests can be of any size, whether initial, update, or final.
327 	 * A non-final request must be submitted to the SPU as an integral
328 	 * number of blocks. This may leave data at the end of the request
329 	 * that is not a full block. Since the request is non-final, it cannot
330 	 * be padded. So, we write the remainder to this hash_carry buffer and
331 	 * hold it until the next request arrives. The carry data is then
332 	 * submitted at the beginning of the data in the next SPU msg.
333 	 * hash_carry_len is the number of bytes currently in hash_carry. These
334 	 * fields are only used for ahash requests.
335 	 */
336 	u8 hash_carry[HASH_CARRY_MAX];
337 	unsigned int hash_carry_len;
338 	unsigned int is_final;	/* is this the final for the hash op? */
339 
340 	/*
341 	 * Digest from incremental hash is saved here to include in next hash
342 	 * operation. Cannot be stored in req->result for truncated hashes,
343 	 * since result may be sized for final digest. Cannot be saved in
344 	 * msg_buf because that gets deleted between incremental hash ops
345 	 * and is not saved as part of export().
346 	 */
347 	u8 incr_hash[MAX_DIGEST_SIZE];
348 
349 	/* hmac context */
350 	bool is_sw_hmac;
351 
352 	/* aead context */
353 	struct crypto_tfm *old_tfm;
354 	crypto_completion_t old_complete;
355 	void *old_data;
356 
357 	gfp_t gfp;
358 
359 	/* Buffers used to build SPU request and response messages */
360 	struct spu_msg_buf msg_buf;
361 };
362 
363 /*
364  * Structure encapsulates a set of function pointers specific to the type of
365  * SPU hardware running. These functions handling creation and parsing of
366  * SPU request messages and SPU response messages. Includes hardware-specific
367  * values read from device tree.
368  */
369 struct spu_hw {
370 	void (*spu_dump_msg_hdr)(u8 *buf, unsigned int buf_len);
371 	u32 (*spu_ctx_max_payload)(enum spu_cipher_alg cipher_alg,
372 				   enum spu_cipher_mode cipher_mode,
373 				   unsigned int blocksize);
374 	u32 (*spu_payload_length)(u8 *spu_hdr);
375 	u16 (*spu_response_hdr_len)(u16 auth_key_len, u16 enc_key_len,
376 				    bool is_hash);
377 	u16 (*spu_hash_pad_len)(enum hash_alg hash_alg,
378 				enum hash_mode hash_mode, u32 chunksize,
379 				u16 hash_block_size);
380 	u32 (*spu_gcm_ccm_pad_len)(enum spu_cipher_mode cipher_mode,
381 				   unsigned int data_size);
382 	u32 (*spu_assoc_resp_len)(enum spu_cipher_mode cipher_mode,
383 				  unsigned int assoc_len,
384 				  unsigned int iv_len, bool is_encrypt);
385 	u8 (*spu_aead_ivlen)(enum spu_cipher_mode cipher_mode,
386 			     u16 iv_len);
387 	enum hash_type (*spu_hash_type)(u32 src_sent);
388 	u32 (*spu_digest_size)(u32 digest_size, enum hash_alg alg,
389 			       enum hash_type);
390 	u32 (*spu_create_request)(u8 *spu_hdr,
391 				  struct spu_request_opts *req_opts,
392 				  struct spu_cipher_parms *cipher_parms,
393 				  struct spu_hash_parms *hash_parms,
394 				  struct spu_aead_parms *aead_parms,
395 				  unsigned int data_size);
396 	u16 (*spu_cipher_req_init)(u8 *spu_hdr,
397 				   struct spu_cipher_parms *cipher_parms);
398 	void (*spu_cipher_req_finish)(u8 *spu_hdr,
399 				      u16 spu_req_hdr_len,
400 				      unsigned int is_inbound,
401 				      struct spu_cipher_parms *cipher_parms,
402 				      bool update_key,
403 				      unsigned int data_size);
404 	void (*spu_request_pad)(u8 *pad_start, u32 gcm_padding,
405 				u32 hash_pad_len, enum hash_alg auth_alg,
406 				enum hash_mode auth_mode,
407 				unsigned int total_sent, u32 status_padding);
408 	u8 (*spu_xts_tweak_in_payload)(void);
409 	u8 (*spu_tx_status_len)(void);
410 	u8 (*spu_rx_status_len)(void);
411 	int (*spu_status_process)(u8 *statp);
412 	void (*spu_ccm_update_iv)(unsigned int digestsize,
413 				  struct spu_cipher_parms *cipher_parms,
414 				  unsigned int assoclen, unsigned int chunksize,
415 				  bool is_encrypt, bool is_esp);
416 	u32 (*spu_wordalign_padlen)(u32 data_size);
417 
418 	/* The base virtual address of the SPU hw registers */
419 	void __iomem *reg_vbase[MAX_SPUS];
420 
421 	/* Version of the SPU hardware */
422 	enum spu_spu_type spu_type;
423 
424 	/* Sub-version of the SPU hardware */
425 	enum spu_spu_subtype spu_subtype;
426 
427 	/* The number of SPUs on this platform */
428 	u32 num_spu;
429 
430 	/* The number of SPU channels on this platform */
431 	u32 num_chan;
432 };
433 
434 struct device_private {
435 	struct platform_device *pdev;
436 
437 	struct spu_hw spu;
438 
439 	atomic_t session_count;	/* number of streams active */
440 	atomic_t stream_count;	/* monotonic counter for streamID's */
441 
442 	/* Length of BCM header. Set to 0 when hw does not expect BCM HEADER. */
443 	u8 bcm_hdr_len;
444 
445 	/* The index of the channel to use for the next crypto request */
446 	atomic_t next_chan;
447 
448 	struct dentry *debugfs_dir;
449 	struct dentry *debugfs_stats;
450 
451 	/* Number of request bytes processed and result bytes returned */
452 	atomic64_t bytes_in;
453 	atomic64_t bytes_out;
454 
455 	/* Number of operations of each type */
456 	atomic_t op_counts[SPU_OP_NUM];
457 
458 	atomic_t cipher_cnt[CIPHER_ALG_LAST][CIPHER_MODE_LAST];
459 	atomic_t hash_cnt[HASH_ALG_LAST];
460 	atomic_t hmac_cnt[HASH_ALG_LAST];
461 	atomic_t aead_cnt[AEAD_TYPE_LAST];
462 
463 	/* Number of calls to setkey() for each operation type */
464 	atomic_t setkey_cnt[SPU_OP_NUM];
465 
466 	/* Number of times request was resubmitted because mb was full */
467 	atomic_t mb_no_spc;
468 
469 	/* Number of mailbox send failures */
470 	atomic_t mb_send_fail;
471 
472 	/* Number of ICV check failures for AEAD messages */
473 	atomic_t bad_icv;
474 
475 	struct mbox_client mcl;
476 
477 	/* Array of mailbox channel pointers, one for each channel */
478 	struct mbox_chan **mbox;
479 };
480 
481 extern struct device_private iproc_priv;
482 
483 #endif
484