xref: /openbmc/linux/drivers/crypto/bcm/cipher.h (revision ae213c44)
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/arc4.h>
27 #include <crypto/gcm.h>
28 #include <crypto/sha.h>
29 #include <crypto/sha3.h>
30 
31 #include "spu.h"
32 #include "spum.h"
33 #include "spu2.h"
34 
35 /* Driver supports up to MAX_SPUS SPU blocks */
36 #define MAX_SPUS 16
37 
38 #define ARC4_STATE_SIZE     4
39 
40 #define CCM_AES_IV_SIZE    16
41 #define CCM_ESP_IV_SIZE     8
42 #define RFC4543_ICV_SIZE   16
43 
44 #define MAX_KEY_SIZE	ARC4_MAX_KEY_SIZE
45 #define MAX_IV_SIZE	AES_BLOCK_SIZE
46 #define MAX_DIGEST_SIZE	SHA3_512_DIGEST_SIZE
47 #define MAX_ASSOC_SIZE	512
48 
49 /* size of salt value for AES-GCM-ESP and AES-CCM-ESP */
50 #define GCM_ESP_SALT_SIZE   4
51 #define CCM_ESP_SALT_SIZE   3
52 #define MAX_SALT_SIZE       GCM_ESP_SALT_SIZE
53 #define GCM_ESP_SALT_OFFSET 0
54 #define CCM_ESP_SALT_OFFSET 1
55 
56 #define GCM_ESP_DIGESTSIZE 16
57 
58 #define MAX_HASH_BLOCK_SIZE SHA512_BLOCK_SIZE
59 
60 /*
61  * Maximum number of bytes from a non-final hash request that can be deferred
62  * until more data is available. With new crypto API framework, this
63  * can be no more than one block of data.
64  */
65 #define HASH_CARRY_MAX  MAX_HASH_BLOCK_SIZE
66 
67 /* Force at least 4-byte alignment of all SPU message fields */
68 #define SPU_MSG_ALIGN  4
69 
70 /* Number of times to resend mailbox message if mb queue is full */
71 #define SPU_MB_RETRY_MAX  1000
72 
73 /* op_counts[] indexes */
74 enum op_type {
75 	SPU_OP_CIPHER,
76 	SPU_OP_HASH,
77 	SPU_OP_HMAC,
78 	SPU_OP_AEAD,
79 	SPU_OP_NUM
80 };
81 
82 enum spu_spu_type {
83 	SPU_TYPE_SPUM,
84 	SPU_TYPE_SPU2,
85 };
86 
87 /*
88  * SPUM_NS2 and SPUM_NSP are the SPU-M block on Northstar 2 and Northstar Plus,
89  * respectively.
90  */
91 enum spu_spu_subtype {
92 	SPU_SUBTYPE_SPUM_NS2,
93 	SPU_SUBTYPE_SPUM_NSP,
94 	SPU_SUBTYPE_SPU2_V1,
95 	SPU_SUBTYPE_SPU2_V2
96 };
97 
98 struct spu_type_subtype {
99 	enum spu_spu_type type;
100 	enum spu_spu_subtype subtype;
101 };
102 
103 struct cipher_op {
104 	enum spu_cipher_alg alg;
105 	enum spu_cipher_mode mode;
106 };
107 
108 struct auth_op {
109 	enum hash_alg alg;
110 	enum hash_mode mode;
111 };
112 
113 struct iproc_alg_s {
114 	u32 type;
115 	union {
116 		struct crypto_alg crypto;
117 		struct ahash_alg hash;
118 		struct aead_alg aead;
119 	} alg;
120 	struct cipher_op cipher_info;
121 	struct auth_op auth_info;
122 	bool auth_first;
123 	bool registered;
124 };
125 
126 /*
127  * Buffers for a SPU request/reply message pair. All part of one structure to
128  * allow a single alloc per request.
129  */
130 struct spu_msg_buf {
131 	/* Request message fragments */
132 
133 	/*
134 	 * SPU request message header. For SPU-M, holds MH, EMH, SCTX, BDESC,
135 	 * and BD header. For SPU2, holds FMD, OMD.
136 	 */
137 	u8 bcm_spu_req_hdr[ALIGN(SPU2_HEADER_ALLOC_LEN, SPU_MSG_ALIGN)];
138 
139 	/* IV or counter. Size to include salt. Also used for XTS tweek. */
140 	u8 iv_ctr[ALIGN(2 * AES_BLOCK_SIZE, SPU_MSG_ALIGN)];
141 
142 	/* Hash digest. request and response. */
143 	u8 digest[ALIGN(MAX_DIGEST_SIZE, SPU_MSG_ALIGN)];
144 
145 	/* SPU request message padding */
146 	u8 spu_req_pad[ALIGN(SPU_PAD_LEN_MAX, SPU_MSG_ALIGN)];
147 
148 	/* SPU-M request message STATUS field */
149 	u8 tx_stat[ALIGN(SPU_TX_STATUS_LEN, SPU_MSG_ALIGN)];
150 
151 	/* Response message fragments */
152 
153 	/* SPU response message header */
154 	u8 spu_resp_hdr[ALIGN(SPU2_HEADER_ALLOC_LEN, SPU_MSG_ALIGN)];
155 
156 	/* SPU response message STATUS field padding */
157 	u8 rx_stat_pad[ALIGN(SPU_STAT_PAD_MAX, SPU_MSG_ALIGN)];
158 
159 	/* SPU response message STATUS field */
160 	u8 rx_stat[ALIGN(SPU_RX_STATUS_LEN, SPU_MSG_ALIGN)];
161 
162 	union {
163 		/* Buffers only used for ablkcipher */
164 		struct {
165 			/*
166 			 * Field used for either SUPDT when RC4 is used
167 			 * -OR- tweak value when XTS/AES is used
168 			 */
169 			u8 supdt_tweak[ALIGN(SPU_SUPDT_LEN, SPU_MSG_ALIGN)];
170 		} c;
171 
172 		/* Buffers only used for aead */
173 		struct {
174 			/* SPU response pad for GCM data */
175 			u8 gcmpad[ALIGN(AES_BLOCK_SIZE, SPU_MSG_ALIGN)];
176 
177 			/* SPU request msg padding for GCM AAD */
178 			u8 req_aad_pad[ALIGN(SPU_PAD_LEN_MAX, SPU_MSG_ALIGN)];
179 
180 			/* SPU response data to be discarded */
181 			u8 resp_aad[ALIGN(MAX_ASSOC_SIZE + MAX_IV_SIZE,
182 					  SPU_MSG_ALIGN)];
183 		} a;
184 	};
185 };
186 
187 struct iproc_ctx_s {
188 	u8 enckey[MAX_KEY_SIZE + ARC4_STATE_SIZE];
189 	unsigned int enckeylen;
190 
191 	u8 authkey[MAX_KEY_SIZE + ARC4_STATE_SIZE];
192 	unsigned int authkeylen;
193 
194 	u8 salt[MAX_SALT_SIZE];
195 	unsigned int salt_len;
196 	unsigned int salt_offset;
197 	u8 iv[MAX_IV_SIZE];
198 
199 	unsigned int digestsize;
200 
201 	struct iproc_alg_s *alg;
202 	bool is_esp;
203 
204 	struct cipher_op cipher;
205 	enum spu_cipher_type cipher_type;
206 
207 	struct auth_op auth;
208 	bool auth_first;
209 
210 	/*
211 	 * The maximum length in bytes of the payload in a SPU message for this
212 	 * context. For SPU-M, the payload is the combination of AAD and data.
213 	 * For SPU2, the payload is just data. A value of SPU_MAX_PAYLOAD_INF
214 	 * indicates that there is no limit to the length of the SPU message
215 	 * payload.
216 	 */
217 	unsigned int max_payload;
218 
219 	struct crypto_aead *fallback_cipher;
220 
221 	/* auth_type is determined during processing of request */
222 
223 	u8 ipad[MAX_HASH_BLOCK_SIZE];
224 	u8 opad[MAX_HASH_BLOCK_SIZE];
225 
226 	/*
227 	 * Buffer to hold SPU message header template. Template is created at
228 	 * setkey time for ablkcipher requests, since most of the fields in the
229 	 * header are known at that time. At request time, just fill in a few
230 	 * missing pieces related to length of data in the request and IVs, etc.
231 	 */
232 	u8 bcm_spu_req_hdr[ALIGN(SPU2_HEADER_ALLOC_LEN, SPU_MSG_ALIGN)];
233 
234 	/* Length of SPU request header */
235 	u16 spu_req_hdr_len;
236 
237 	/* Expected length of SPU response header */
238 	u16 spu_resp_hdr_len;
239 
240 	/*
241 	 * shash descriptor - needed to perform incremental hashing in
242 	 * in software, when hw doesn't support it.
243 	 */
244 	struct shash_desc *shash;
245 
246 	bool is_rfc4543;	/* RFC 4543 style of GMAC */
247 };
248 
249 /* state from iproc_reqctx_s necessary for hash state export/import */
250 struct spu_hash_export_s {
251 	unsigned int total_todo;
252 	unsigned int total_sent;
253 	u8 hash_carry[HASH_CARRY_MAX];
254 	unsigned int hash_carry_len;
255 	u8 incr_hash[MAX_DIGEST_SIZE];
256 	bool is_sw_hmac;
257 };
258 
259 struct iproc_reqctx_s {
260 	/* general context */
261 	struct crypto_async_request *parent;
262 
263 	/* only valid after enqueue() */
264 	struct iproc_ctx_s *ctx;
265 
266 	u8 chan_idx;   /* Mailbox channel to be used to submit this request */
267 
268 	/* total todo, rx'd, and sent for this request */
269 	unsigned int total_todo;
270 	unsigned int total_received;	/* only valid for ablkcipher */
271 	unsigned int total_sent;
272 
273 	/*
274 	 * num bytes sent to hw from the src sg in this request. This can differ
275 	 * from total_sent for incremental hashing. total_sent includes previous
276 	 * init() and update() data. src_sent does not.
277 	 */
278 	unsigned int src_sent;
279 
280 	/*
281 	 * For AEAD requests, start of associated data. This will typically
282 	 * point to the beginning of the src scatterlist from the request,
283 	 * since assoc data is at the beginning of the src scatterlist rather
284 	 * than in its own sg.
285 	 */
286 	struct scatterlist *assoc;
287 
288 	/*
289 	 * scatterlist entry and offset to start of data for next chunk. Crypto
290 	 * API src scatterlist for AEAD starts with AAD, if present. For first
291 	 * chunk, src_sg is sg entry at beginning of input data (after AAD).
292 	 * src_skip begins at the offset in that sg entry where data begins.
293 	 */
294 	struct scatterlist *src_sg;
295 	int src_nents;		/* Number of src entries with data */
296 	u32 src_skip;		/* bytes of current sg entry already used */
297 
298 	/*
299 	 * Same for destination. For AEAD, if there is AAD, output data must
300 	 * be written at offset following AAD.
301 	 */
302 	struct scatterlist *dst_sg;
303 	int dst_nents;		/* Number of dst entries with data */
304 	u32 dst_skip;		/* bytes of current sg entry already written */
305 
306 	/* Mailbox message used to send this request to PDC driver */
307 	struct brcm_message mb_mssg;
308 
309 	bool bd_suppress;	/* suppress BD field in SPU response? */
310 
311 	/* cipher context */
312 	bool is_encrypt;
313 
314 	/*
315 	 * CBC mode: IV.  CTR mode: counter.  Else empty. Used as a DMA
316 	 * buffer for AEAD requests. So allocate as DMAable memory. If IV
317 	 * concatenated with salt, includes the salt.
318 	 */
319 	u8 *iv_ctr;
320 	/* Length of IV or counter, in bytes */
321 	unsigned int iv_ctr_len;
322 
323 	/*
324 	 * Hash requests can be of any size, whether initial, update, or final.
325 	 * A non-final request must be submitted to the SPU as an integral
326 	 * number of blocks. This may leave data at the end of the request
327 	 * that is not a full block. Since the request is non-final, it cannot
328 	 * be padded. So, we write the remainder to this hash_carry buffer and
329 	 * hold it until the next request arrives. The carry data is then
330 	 * submitted at the beginning of the data in the next SPU msg.
331 	 * hash_carry_len is the number of bytes currently in hash_carry. These
332 	 * fields are only used for ahash requests.
333 	 */
334 	u8 hash_carry[HASH_CARRY_MAX];
335 	unsigned int hash_carry_len;
336 	unsigned int is_final;	/* is this the final for the hash op? */
337 
338 	/*
339 	 * Digest from incremental hash is saved here to include in next hash
340 	 * operation. Cannot be stored in req->result for truncated hashes,
341 	 * since result may be sized for final digest. Cannot be saved in
342 	 * msg_buf because that gets deleted between incremental hash ops
343 	 * and is not saved as part of export().
344 	 */
345 	u8 incr_hash[MAX_DIGEST_SIZE];
346 
347 	/* hmac context */
348 	bool is_sw_hmac;
349 
350 	/* aead context */
351 	struct crypto_tfm *old_tfm;
352 	crypto_completion_t old_complete;
353 	void *old_data;
354 
355 	gfp_t gfp;
356 
357 	/* Buffers used to build SPU request and response messages */
358 	struct spu_msg_buf msg_buf;
359 };
360 
361 /*
362  * Structure encapsulates a set of function pointers specific to the type of
363  * SPU hardware running. These functions handling creation and parsing of
364  * SPU request messages and SPU response messages. Includes hardware-specific
365  * values read from device tree.
366  */
367 struct spu_hw {
368 	void (*spu_dump_msg_hdr)(u8 *buf, unsigned int buf_len);
369 	u32 (*spu_ctx_max_payload)(enum spu_cipher_alg cipher_alg,
370 				   enum spu_cipher_mode cipher_mode,
371 				   unsigned int blocksize);
372 	u32 (*spu_payload_length)(u8 *spu_hdr);
373 	u16 (*spu_response_hdr_len)(u16 auth_key_len, u16 enc_key_len,
374 				    bool is_hash);
375 	u16 (*spu_hash_pad_len)(enum hash_alg hash_alg,
376 				enum hash_mode hash_mode, u32 chunksize,
377 				u16 hash_block_size);
378 	u32 (*spu_gcm_ccm_pad_len)(enum spu_cipher_mode cipher_mode,
379 				   unsigned int data_size);
380 	u32 (*spu_assoc_resp_len)(enum spu_cipher_mode cipher_mode,
381 				  unsigned int assoc_len,
382 				  unsigned int iv_len, bool is_encrypt);
383 	u8 (*spu_aead_ivlen)(enum spu_cipher_mode cipher_mode,
384 			     u16 iv_len);
385 	enum hash_type (*spu_hash_type)(u32 src_sent);
386 	u32 (*spu_digest_size)(u32 digest_size, enum hash_alg alg,
387 			       enum hash_type);
388 	u32 (*spu_create_request)(u8 *spu_hdr,
389 				  struct spu_request_opts *req_opts,
390 				  struct spu_cipher_parms *cipher_parms,
391 				  struct spu_hash_parms *hash_parms,
392 				  struct spu_aead_parms *aead_parms,
393 				  unsigned int data_size);
394 	u16 (*spu_cipher_req_init)(u8 *spu_hdr,
395 				   struct spu_cipher_parms *cipher_parms);
396 	void (*spu_cipher_req_finish)(u8 *spu_hdr,
397 				      u16 spu_req_hdr_len,
398 				      unsigned int is_inbound,
399 				      struct spu_cipher_parms *cipher_parms,
400 				      bool update_key,
401 				      unsigned int data_size);
402 	void (*spu_request_pad)(u8 *pad_start, u32 gcm_padding,
403 				u32 hash_pad_len, enum hash_alg auth_alg,
404 				enum hash_mode auth_mode,
405 				unsigned int total_sent, u32 status_padding);
406 	u8 (*spu_xts_tweak_in_payload)(void);
407 	u8 (*spu_tx_status_len)(void);
408 	u8 (*spu_rx_status_len)(void);
409 	int (*spu_status_process)(u8 *statp);
410 	void (*spu_ccm_update_iv)(unsigned int digestsize,
411 				  struct spu_cipher_parms *cipher_parms,
412 				  unsigned int assoclen, unsigned int chunksize,
413 				  bool is_encrypt, bool is_esp);
414 	u32 (*spu_wordalign_padlen)(u32 data_size);
415 
416 	/* The base virtual address of the SPU hw registers */
417 	void __iomem *reg_vbase[MAX_SPUS];
418 
419 	/* Version of the SPU hardware */
420 	enum spu_spu_type spu_type;
421 
422 	/* Sub-version of the SPU hardware */
423 	enum spu_spu_subtype spu_subtype;
424 
425 	/* The number of SPUs on this platform */
426 	u32 num_spu;
427 
428 	/* The number of SPU channels on this platform */
429 	u32 num_chan;
430 };
431 
432 struct device_private {
433 	struct platform_device *pdev;
434 
435 	struct spu_hw spu;
436 
437 	atomic_t session_count;	/* number of streams active */
438 	atomic_t stream_count;	/* monotonic counter for streamID's */
439 
440 	/* Length of BCM header. Set to 0 when hw does not expect BCM HEADER. */
441 	u8 bcm_hdr_len;
442 
443 	/* The index of the channel to use for the next crypto request */
444 	atomic_t next_chan;
445 
446 	struct dentry *debugfs_dir;
447 	struct dentry *debugfs_stats;
448 
449 	/* Number of request bytes processed and result bytes returned */
450 	atomic64_t bytes_in;
451 	atomic64_t bytes_out;
452 
453 	/* Number of operations of each type */
454 	atomic_t op_counts[SPU_OP_NUM];
455 
456 	atomic_t cipher_cnt[CIPHER_ALG_LAST][CIPHER_MODE_LAST];
457 	atomic_t hash_cnt[HASH_ALG_LAST];
458 	atomic_t hmac_cnt[HASH_ALG_LAST];
459 	atomic_t aead_cnt[AEAD_TYPE_LAST];
460 
461 	/* Number of calls to setkey() for each operation type */
462 	atomic_t setkey_cnt[SPU_OP_NUM];
463 
464 	/* Number of times request was resubmitted because mb was full */
465 	atomic_t mb_no_spc;
466 
467 	/* Number of mailbox send failures */
468 	atomic_t mb_send_fail;
469 
470 	/* Number of ICV check failures for AEAD messages */
471 	atomic_t bad_icv;
472 
473 	struct mbox_client mcl;
474 
475 	/* Array of mailbox channel pointers, one for each channel */
476 	struct mbox_chan **mbox;
477 };
478 
479 extern struct device_private iproc_priv;
480 
481 #endif
482