xref: /linux/include/crypto/algapi.h (revision 903be6989032267550450bbb9132225e12f61312)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Cryptographic API for algorithms (i.e., low-level API).
4  *
5  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
6  */
7 #ifndef _CRYPTO_ALGAPI_H
8 #define _CRYPTO_ALGAPI_H
9 
10 #include <crypto/utils.h>
11 #include <linux/align.h>
12 #include <linux/cache.h>
13 #include <linux/crypto.h>
14 #include <linux/list.h>
15 #include <linux/types.h>
16 #include <linux/workqueue.h>
17 
18 /*
19  * Maximum values for blocksize and alignmask, used to allocate
20  * static buffers that are big enough for any combination of
21  * algs and architectures. Ciphers have a lower maximum size.
22  */
23 #define MAX_ALGAPI_BLOCKSIZE		160
24 #define MAX_ALGAPI_ALIGNMASK		127
25 #define MAX_CIPHER_BLOCKSIZE		16
26 #define MAX_CIPHER_ALIGNMASK		15
27 
28 #ifdef ARCH_DMA_MINALIGN
29 #define CRYPTO_DMA_ALIGN ARCH_DMA_MINALIGN
30 #else
31 #define CRYPTO_DMA_ALIGN CRYPTO_MINALIGN
32 #endif
33 
34 #define CRYPTO_DMA_PADDING ((CRYPTO_DMA_ALIGN - 1) & ~(CRYPTO_MINALIGN - 1))
35 
36 /*
37  * Autoloaded crypto modules should only use a prefixed name to avoid allowing
38  * arbitrary modules to be loaded. Loading from userspace may still need the
39  * unprefixed names, so retains those aliases as well.
40  * This uses __MODULE_INFO directly instead of MODULE_ALIAS because pre-4.3
41  * gcc (e.g. avr32 toolchain) uses __LINE__ for uniqueness, and this macro
42  * expands twice on the same line. Instead, use a separate base name for the
43  * alias.
44  */
45 #define MODULE_ALIAS_CRYPTO(name)	\
46 		__MODULE_INFO(alias, alias_userspace, name);	\
47 		__MODULE_INFO(alias, alias_crypto, "crypto-" name)
48 
49 struct crypto_aead;
50 struct crypto_instance;
51 struct module;
52 struct notifier_block;
53 struct rtattr;
54 struct scatterlist;
55 struct seq_file;
56 struct sk_buff;
57 
58 struct crypto_type {
59 	unsigned int (*ctxsize)(struct crypto_alg *alg, u32 type, u32 mask);
60 	unsigned int (*extsize)(struct crypto_alg *alg);
61 	int (*init_tfm)(struct crypto_tfm *tfm);
62 	void (*show)(struct seq_file *m, struct crypto_alg *alg);
63 	int (*report)(struct sk_buff *skb, struct crypto_alg *alg);
64 	void (*free)(struct crypto_instance *inst);
65 
66 	unsigned int type;
67 	unsigned int maskclear;
68 	unsigned int maskset;
69 	unsigned int tfmsize;
70 };
71 
72 struct crypto_instance {
73 	struct crypto_alg alg;
74 
75 	struct crypto_template *tmpl;
76 
77 	union {
78 		/* Node in list of instances after registration. */
79 		struct hlist_node list;
80 		/* List of attached spawns before registration. */
81 		struct crypto_spawn *spawns;
82 	};
83 
84 	struct work_struct free_work;
85 
86 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
87 };
88 
89 struct crypto_template {
90 	struct list_head list;
91 	struct hlist_head instances;
92 	struct module *module;
93 
94 	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);
95 
96 	char name[CRYPTO_MAX_ALG_NAME];
97 };
98 
99 struct crypto_spawn {
100 	struct list_head list;
101 	struct crypto_alg *alg;
102 	union {
103 		/* Back pointer to instance after registration.*/
104 		struct crypto_instance *inst;
105 		/* Spawn list pointer prior to registration. */
106 		struct crypto_spawn *next;
107 	};
108 	const struct crypto_type *frontend;
109 	u32 mask;
110 	bool dead;
111 	bool registered;
112 };
113 
114 struct crypto_queue {
115 	struct list_head list;
116 	struct list_head *backlog;
117 
118 	unsigned int qlen;
119 	unsigned int max_qlen;
120 };
121 
122 struct scatter_walk {
123 	struct scatterlist *sg;
124 	unsigned int offset;
125 };
126 
127 struct crypto_attr_alg {
128 	char name[CRYPTO_MAX_ALG_NAME];
129 };
130 
131 struct crypto_attr_type {
132 	u32 type;
133 	u32 mask;
134 };
135 
136 /*
137  * Algorithm registration interface.
138  */
139 int crypto_register_alg(struct crypto_alg *alg);
140 void crypto_unregister_alg(struct crypto_alg *alg);
141 int crypto_register_algs(struct crypto_alg *algs, int count);
142 void crypto_unregister_algs(struct crypto_alg *algs, int count);
143 
144 void crypto_mod_put(struct crypto_alg *alg);
145 
146 int crypto_register_template(struct crypto_template *tmpl);
147 int crypto_register_templates(struct crypto_template *tmpls, int count);
148 void crypto_unregister_template(struct crypto_template *tmpl);
149 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
150 struct crypto_template *crypto_lookup_template(const char *name);
151 
152 int crypto_register_instance(struct crypto_template *tmpl,
153 			     struct crypto_instance *inst);
154 void crypto_unregister_instance(struct crypto_instance *inst);
155 
156 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
157 		      const char *name, u32 type, u32 mask);
158 void crypto_drop_spawn(struct crypto_spawn *spawn);
159 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
160 				    u32 mask);
161 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
162 
163 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
164 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
165 const char *crypto_attr_alg_name(struct rtattr *rta);
166 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
167 			struct crypto_alg *alg);
168 
169 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
170 int crypto_enqueue_request(struct crypto_queue *queue,
171 			   struct crypto_async_request *request);
172 void crypto_enqueue_request_head(struct crypto_queue *queue,
173 				 struct crypto_async_request *request);
174 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
175 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
176 {
177 	return queue->qlen;
178 }
179 
180 void crypto_inc(u8 *a, unsigned int size);
181 
182 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
183 {
184 	return tfm->__crt_ctx;
185 }
186 
187 static inline void *crypto_tfm_ctx_align(struct crypto_tfm *tfm,
188 					 unsigned int align)
189 {
190 	if (align <= crypto_tfm_ctx_alignment())
191 		align = 1;
192 
193 	return PTR_ALIGN(crypto_tfm_ctx(tfm), align);
194 }
195 
196 static inline unsigned int crypto_dma_align(void)
197 {
198 	return CRYPTO_DMA_ALIGN;
199 }
200 
201 static inline unsigned int crypto_dma_padding(void)
202 {
203 	return (crypto_dma_align() - 1) & ~(crypto_tfm_ctx_alignment() - 1);
204 }
205 
206 static inline void *crypto_tfm_ctx_dma(struct crypto_tfm *tfm)
207 {
208 	return crypto_tfm_ctx_align(tfm, crypto_dma_align());
209 }
210 
211 static inline struct crypto_instance *crypto_tfm_alg_instance(
212 	struct crypto_tfm *tfm)
213 {
214 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
215 }
216 
217 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
218 {
219 	return inst->__ctx;
220 }
221 
222 static inline struct crypto_async_request *crypto_get_backlog(
223 	struct crypto_queue *queue)
224 {
225 	return queue->backlog == &queue->list ? NULL :
226 	       container_of(queue->backlog, struct crypto_async_request, list);
227 }
228 
229 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
230 {
231 	return (algt->type ^ off) & algt->mask & off;
232 }
233 
234 /*
235  * When an algorithm uses another algorithm (e.g., if it's an instance of a
236  * template), these are the flags that should always be set on the "outer"
237  * algorithm if any "inner" algorithm has them set.
238  */
239 #define CRYPTO_ALG_INHERITED_FLAGS	\
240 	(CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |	\
241 	 CRYPTO_ALG_ALLOCATES_MEMORY)
242 
243 /*
244  * Given the type and mask that specify the flags restrictions on a template
245  * instance being created, return the mask that should be passed to
246  * crypto_grab_*() (along with type=0) to honor any request the user made to
247  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
248  */
249 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
250 {
251 	return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
252 }
253 
254 int crypto_register_notifier(struct notifier_block *nb);
255 int crypto_unregister_notifier(struct notifier_block *nb);
256 
257 /* Crypto notification events. */
258 enum {
259 	CRYPTO_MSG_ALG_REQUEST,
260 	CRYPTO_MSG_ALG_REGISTER,
261 	CRYPTO_MSG_ALG_LOADED,
262 };
263 
264 static inline void crypto_request_complete(struct crypto_async_request *req,
265 					   int err)
266 {
267 	req->complete(req->data, err);
268 }
269 
270 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
271 {
272 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
273 }
274 
275 static inline bool crypto_request_chained(struct crypto_async_request *req)
276 {
277 	return !list_empty(&req->list);
278 }
279 
280 static inline bool crypto_tfm_req_chain(struct crypto_tfm *tfm)
281 {
282 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_REQ_CHAIN;
283 }
284 
285 #endif	/* _CRYPTO_ALGAPI_H */
286