xref: /linux/include/crypto/algapi.h (revision 184e56e77c06a7eef68a021e9d4b11a11a8ab096)
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 union crypto_no_such_thing;
58 
59 struct crypto_instance {
60 	struct crypto_alg alg;
61 
62 	struct crypto_template *tmpl;
63 
64 	union {
65 		/* Node in list of instances after registration. */
66 		struct hlist_node list;
67 		/* List of attached spawns before registration. */
68 		struct crypto_spawn *spawns;
69 	};
70 
71 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
72 };
73 
74 struct crypto_template {
75 	struct list_head list;
76 	struct hlist_head instances;
77 	struct hlist_head dead;
78 	struct module *module;
79 
80 	struct work_struct free_work;
81 
82 	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);
83 
84 	char name[CRYPTO_MAX_ALG_NAME];
85 };
86 
87 struct crypto_spawn {
88 	struct list_head list;
89 	struct crypto_alg *alg;
90 	union {
91 		/* Back pointer to instance after registration.*/
92 		struct crypto_instance *inst;
93 		/* Spawn list pointer prior to registration. */
94 		struct crypto_spawn *next;
95 	};
96 	const struct crypto_type *frontend;
97 	u32 mask;
98 	bool dead;
99 	bool registered;
100 };
101 
102 struct crypto_queue {
103 	struct list_head list;
104 	struct list_head *backlog;
105 
106 	unsigned int qlen;
107 	unsigned int max_qlen;
108 };
109 
110 struct scatter_walk {
111 	/* Must be the first member, see struct skcipher_walk. */
112 	union {
113 		void *const addr;
114 
115 		/* Private API field, do not touch. */
116 		union crypto_no_such_thing *__addr;
117 	};
118 	struct scatterlist *sg;
119 	unsigned int offset;
120 };
121 
122 struct crypto_attr_alg {
123 	char name[CRYPTO_MAX_ALG_NAME];
124 };
125 
126 struct crypto_attr_type {
127 	u32 type;
128 	u32 mask;
129 };
130 
131 /*
132  * Algorithm registration interface.
133  */
134 int crypto_register_alg(struct crypto_alg *alg);
135 void crypto_unregister_alg(struct crypto_alg *alg);
136 int crypto_register_algs(struct crypto_alg *algs, int count);
137 void crypto_unregister_algs(struct crypto_alg *algs, int count);
138 
139 void crypto_mod_put(struct crypto_alg *alg);
140 
141 int crypto_register_template(struct crypto_template *tmpl);
142 int crypto_register_templates(struct crypto_template *tmpls, int count);
143 void crypto_unregister_template(struct crypto_template *tmpl);
144 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
145 struct crypto_template *crypto_lookup_template(const char *name);
146 
147 int crypto_register_instance(struct crypto_template *tmpl,
148 			     struct crypto_instance *inst);
149 void crypto_unregister_instance(struct crypto_instance *inst);
150 
151 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
152 		      const char *name, u32 type, u32 mask);
153 void crypto_drop_spawn(struct crypto_spawn *spawn);
154 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
155 				    u32 mask);
156 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
157 
158 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
159 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
160 const char *crypto_attr_alg_name(struct rtattr *rta);
161 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
162 			struct crypto_alg *alg);
163 
164 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
165 int crypto_enqueue_request(struct crypto_queue *queue,
166 			   struct crypto_async_request *request);
167 void crypto_enqueue_request_head(struct crypto_queue *queue,
168 				 struct crypto_async_request *request);
169 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
170 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
171 {
172 	return queue->qlen;
173 }
174 
175 void crypto_inc(u8 *a, unsigned int size);
176 
177 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
178 {
179 	return tfm->__crt_ctx;
180 }
181 
182 static inline void *crypto_tfm_ctx_align(struct crypto_tfm *tfm,
183 					 unsigned int align)
184 {
185 	if (align <= crypto_tfm_ctx_alignment())
186 		align = 1;
187 
188 	return PTR_ALIGN(crypto_tfm_ctx(tfm), align);
189 }
190 
191 static inline unsigned int crypto_dma_align(void)
192 {
193 	return CRYPTO_DMA_ALIGN;
194 }
195 
196 static inline unsigned int crypto_dma_padding(void)
197 {
198 	return (crypto_dma_align() - 1) & ~(crypto_tfm_ctx_alignment() - 1);
199 }
200 
201 static inline void *crypto_tfm_ctx_dma(struct crypto_tfm *tfm)
202 {
203 	return crypto_tfm_ctx_align(tfm, crypto_dma_align());
204 }
205 
206 static inline struct crypto_instance *crypto_tfm_alg_instance(
207 	struct crypto_tfm *tfm)
208 {
209 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
210 }
211 
212 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
213 {
214 	return inst->__ctx;
215 }
216 
217 static inline struct crypto_async_request *crypto_get_backlog(
218 	struct crypto_queue *queue)
219 {
220 	return queue->backlog == &queue->list ? NULL :
221 	       container_of(queue->backlog, struct crypto_async_request, list);
222 }
223 
224 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
225 {
226 	return (algt->type ^ off) & algt->mask & off;
227 }
228 
229 /*
230  * When an algorithm uses another algorithm (e.g., if it's an instance of a
231  * template), these are the flags that should always be set on the "outer"
232  * algorithm if any "inner" algorithm has them set.
233  */
234 #define CRYPTO_ALG_INHERITED_FLAGS	\
235 	(CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |	\
236 	 CRYPTO_ALG_ALLOCATES_MEMORY)
237 
238 /*
239  * Given the type and mask that specify the flags restrictions on a template
240  * instance being created, return the mask that should be passed to
241  * crypto_grab_*() (along with type=0) to honor any request the user made to
242  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
243  */
244 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
245 {
246 	return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
247 }
248 
249 int crypto_register_notifier(struct notifier_block *nb);
250 int crypto_unregister_notifier(struct notifier_block *nb);
251 
252 /* Crypto notification events. */
253 enum {
254 	CRYPTO_MSG_ALG_REQUEST,
255 	CRYPTO_MSG_ALG_REGISTER,
256 	CRYPTO_MSG_ALG_LOADED,
257 };
258 
259 static inline void crypto_request_complete(struct crypto_async_request *req,
260 					   int err)
261 {
262 	req->complete(req->data, err);
263 }
264 
265 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
266 {
267 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
268 }
269 
270 static inline bool crypto_request_chained(struct crypto_async_request *req)
271 {
272 	return !list_empty(&req->list);
273 }
274 
275 static inline bool crypto_tfm_req_chain(struct crypto_tfm *tfm)
276 {
277 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_REQ_CHAIN;
278 }
279 
280 #endif	/* _CRYPTO_ALGAPI_H */
281