xref: /linux/include/crypto/algapi.h (revision db873be6f0549597f92c72986b1939643a7f9a75)
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 	struct work_struct free_work;
72 
73 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
74 };
75 
76 struct crypto_template {
77 	struct list_head list;
78 	struct hlist_head instances;
79 	struct module *module;
80 
81 	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);
82 
83 	char name[CRYPTO_MAX_ALG_NAME];
84 };
85 
86 struct crypto_spawn {
87 	struct list_head list;
88 	struct crypto_alg *alg;
89 	union {
90 		/* Back pointer to instance after registration.*/
91 		struct crypto_instance *inst;
92 		/* Spawn list pointer prior to registration. */
93 		struct crypto_spawn *next;
94 	};
95 	const struct crypto_type *frontend;
96 	u32 mask;
97 	bool dead;
98 	bool registered;
99 };
100 
101 struct crypto_queue {
102 	struct list_head list;
103 	struct list_head *backlog;
104 
105 	unsigned int qlen;
106 	unsigned int max_qlen;
107 };
108 
109 struct scatter_walk {
110 	/* Must be the first member, see struct skcipher_walk. */
111 	union {
112 		void *const addr;
113 
114 		/* Private API field, do not touch. */
115 		union crypto_no_such_thing *__addr;
116 	};
117 	struct scatterlist *sg;
118 	unsigned int offset;
119 };
120 
121 struct crypto_attr_alg {
122 	char name[CRYPTO_MAX_ALG_NAME];
123 };
124 
125 struct crypto_attr_type {
126 	u32 type;
127 	u32 mask;
128 };
129 
130 /*
131  * Algorithm registration interface.
132  */
133 int crypto_register_alg(struct crypto_alg *alg);
134 void crypto_unregister_alg(struct crypto_alg *alg);
135 int crypto_register_algs(struct crypto_alg *algs, int count);
136 void crypto_unregister_algs(struct crypto_alg *algs, int count);
137 
138 void crypto_mod_put(struct crypto_alg *alg);
139 
140 int crypto_register_template(struct crypto_template *tmpl);
141 int crypto_register_templates(struct crypto_template *tmpls, int count);
142 void crypto_unregister_template(struct crypto_template *tmpl);
143 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
144 struct crypto_template *crypto_lookup_template(const char *name);
145 
146 int crypto_register_instance(struct crypto_template *tmpl,
147 			     struct crypto_instance *inst);
148 void crypto_unregister_instance(struct crypto_instance *inst);
149 
150 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
151 		      const char *name, u32 type, u32 mask);
152 void crypto_drop_spawn(struct crypto_spawn *spawn);
153 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
154 				    u32 mask);
155 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
156 
157 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
158 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
159 const char *crypto_attr_alg_name(struct rtattr *rta);
160 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
161 			struct crypto_alg *alg);
162 
163 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
164 int crypto_enqueue_request(struct crypto_queue *queue,
165 			   struct crypto_async_request *request);
166 void crypto_enqueue_request_head(struct crypto_queue *queue,
167 				 struct crypto_async_request *request);
168 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
169 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
170 {
171 	return queue->qlen;
172 }
173 
174 void crypto_inc(u8 *a, unsigned int size);
175 
176 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
177 {
178 	return tfm->__crt_ctx;
179 }
180 
181 static inline void *crypto_tfm_ctx_align(struct crypto_tfm *tfm,
182 					 unsigned int align)
183 {
184 	if (align <= crypto_tfm_ctx_alignment())
185 		align = 1;
186 
187 	return PTR_ALIGN(crypto_tfm_ctx(tfm), align);
188 }
189 
190 static inline unsigned int crypto_dma_align(void)
191 {
192 	return CRYPTO_DMA_ALIGN;
193 }
194 
195 static inline unsigned int crypto_dma_padding(void)
196 {
197 	return (crypto_dma_align() - 1) & ~(crypto_tfm_ctx_alignment() - 1);
198 }
199 
200 static inline void *crypto_tfm_ctx_dma(struct crypto_tfm *tfm)
201 {
202 	return crypto_tfm_ctx_align(tfm, crypto_dma_align());
203 }
204 
205 static inline struct crypto_instance *crypto_tfm_alg_instance(
206 	struct crypto_tfm *tfm)
207 {
208 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
209 }
210 
211 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
212 {
213 	return inst->__ctx;
214 }
215 
216 static inline struct crypto_async_request *crypto_get_backlog(
217 	struct crypto_queue *queue)
218 {
219 	return queue->backlog == &queue->list ? NULL :
220 	       container_of(queue->backlog, struct crypto_async_request, list);
221 }
222 
223 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
224 {
225 	return (algt->type ^ off) & algt->mask & off;
226 }
227 
228 /*
229  * When an algorithm uses another algorithm (e.g., if it's an instance of a
230  * template), these are the flags that should always be set on the "outer"
231  * algorithm if any "inner" algorithm has them set.
232  */
233 #define CRYPTO_ALG_INHERITED_FLAGS	\
234 	(CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |	\
235 	 CRYPTO_ALG_ALLOCATES_MEMORY)
236 
237 /*
238  * Given the type and mask that specify the flags restrictions on a template
239  * instance being created, return the mask that should be passed to
240  * crypto_grab_*() (along with type=0) to honor any request the user made to
241  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
242  */
243 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
244 {
245 	return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
246 }
247 
248 int crypto_register_notifier(struct notifier_block *nb);
249 int crypto_unregister_notifier(struct notifier_block *nb);
250 
251 /* Crypto notification events. */
252 enum {
253 	CRYPTO_MSG_ALG_REQUEST,
254 	CRYPTO_MSG_ALG_REGISTER,
255 	CRYPTO_MSG_ALG_LOADED,
256 };
257 
258 static inline void crypto_request_complete(struct crypto_async_request *req,
259 					   int err)
260 {
261 	req->complete(req->data, err);
262 }
263 
264 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
265 {
266 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
267 }
268 
269 static inline bool crypto_request_chained(struct crypto_async_request *req)
270 {
271 	return !list_empty(&req->list);
272 }
273 
274 static inline bool crypto_tfm_req_chain(struct crypto_tfm *tfm)
275 {
276 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_REQ_CHAIN;
277 }
278 
279 #endif	/* _CRYPTO_ALGAPI_H */
280