xref: /linux/include/crypto/algapi.h (revision da5b2ad1c2f18834cb1ce429e2e5a5cf5cbdf21b)
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/types.h>
15 #include <linux/workqueue.h>
16 
17 /*
18  * Maximum values for blocksize and alignmask, used to allocate
19  * static buffers that are big enough for any combination of
20  * algs and architectures. Ciphers have a lower maximum size.
21  */
22 #define MAX_ALGAPI_BLOCKSIZE		160
23 #define MAX_ALGAPI_ALIGNMASK		127
24 #define MAX_CIPHER_BLOCKSIZE		16
25 #define MAX_CIPHER_ALIGNMASK		15
26 
27 #ifdef ARCH_DMA_MINALIGN
28 #define CRYPTO_DMA_ALIGN ARCH_DMA_MINALIGN
29 #else
30 #define CRYPTO_DMA_ALIGN CRYPTO_MINALIGN
31 #endif
32 
33 #define CRYPTO_DMA_PADDING ((CRYPTO_DMA_ALIGN - 1) & ~(CRYPTO_MINALIGN - 1))
34 
35 /*
36  * Autoloaded crypto modules should only use a prefixed name to avoid allowing
37  * arbitrary modules to be loaded. Loading from userspace may still need the
38  * unprefixed names, so retains those aliases as well.
39  * This uses __MODULE_INFO directly instead of MODULE_ALIAS because pre-4.3
40  * gcc (e.g. avr32 toolchain) uses __LINE__ for uniqueness, and this macro
41  * expands twice on the same line. Instead, use a separate base name for the
42  * alias.
43  */
44 #define MODULE_ALIAS_CRYPTO(name)	\
45 		__MODULE_INFO(alias, alias_userspace, name);	\
46 		__MODULE_INFO(alias, alias_crypto, "crypto-" name)
47 
48 struct crypto_aead;
49 struct crypto_instance;
50 struct module;
51 struct notifier_block;
52 struct rtattr;
53 struct scatterlist;
54 struct seq_file;
55 struct sk_buff;
56 
57 struct crypto_type {
58 	unsigned int (*ctxsize)(struct crypto_alg *alg, u32 type, u32 mask);
59 	unsigned int (*extsize)(struct crypto_alg *alg);
60 	int (*init_tfm)(struct crypto_tfm *tfm);
61 	void (*show)(struct seq_file *m, struct crypto_alg *alg);
62 	int (*report)(struct sk_buff *skb, struct crypto_alg *alg);
63 	void (*free)(struct crypto_instance *inst);
64 
65 	unsigned int type;
66 	unsigned int maskclear;
67 	unsigned int maskset;
68 	unsigned int tfmsize;
69 };
70 
71 struct crypto_instance {
72 	struct crypto_alg alg;
73 
74 	struct crypto_template *tmpl;
75 
76 	union {
77 		/* Node in list of instances after registration. */
78 		struct hlist_node list;
79 		/* List of attached spawns before registration. */
80 		struct crypto_spawn *spawns;
81 	};
82 
83 	struct work_struct free_work;
84 
85 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
86 };
87 
88 struct crypto_template {
89 	struct list_head list;
90 	struct hlist_head instances;
91 	struct module *module;
92 
93 	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);
94 
95 	char name[CRYPTO_MAX_ALG_NAME];
96 };
97 
98 struct crypto_spawn {
99 	struct list_head list;
100 	struct crypto_alg *alg;
101 	union {
102 		/* Back pointer to instance after registration.*/
103 		struct crypto_instance *inst;
104 		/* Spawn list pointer prior to registration. */
105 		struct crypto_spawn *next;
106 	};
107 	const struct crypto_type *frontend;
108 	u32 mask;
109 	bool dead;
110 	bool registered;
111 };
112 
113 struct crypto_queue {
114 	struct list_head list;
115 	struct list_head *backlog;
116 
117 	unsigned int qlen;
118 	unsigned int max_qlen;
119 };
120 
121 struct scatter_walk {
122 	struct scatterlist *sg;
123 	unsigned int offset;
124 };
125 
126 struct crypto_attr_alg {
127 	char name[CRYPTO_MAX_ALG_NAME];
128 };
129 
130 struct crypto_attr_type {
131 	u32 type;
132 	u32 mask;
133 };
134 
135 /*
136  * Algorithm registration interface.
137  */
138 int crypto_register_alg(struct crypto_alg *alg);
139 void crypto_unregister_alg(struct crypto_alg *alg);
140 int crypto_register_algs(struct crypto_alg *algs, int count);
141 void crypto_unregister_algs(struct crypto_alg *algs, int count);
142 
143 void crypto_mod_put(struct crypto_alg *alg);
144 
145 int crypto_register_template(struct crypto_template *tmpl);
146 int crypto_register_templates(struct crypto_template *tmpls, int count);
147 void crypto_unregister_template(struct crypto_template *tmpl);
148 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
149 struct crypto_template *crypto_lookup_template(const char *name);
150 
151 int crypto_register_instance(struct crypto_template *tmpl,
152 			     struct crypto_instance *inst);
153 void crypto_unregister_instance(struct crypto_instance *inst);
154 
155 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
156 		      const char *name, u32 type, u32 mask);
157 void crypto_drop_spawn(struct crypto_spawn *spawn);
158 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
159 				    u32 mask);
160 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
161 
162 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
163 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
164 const char *crypto_attr_alg_name(struct rtattr *rta);
165 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
166 			struct crypto_alg *alg);
167 
168 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
169 int crypto_enqueue_request(struct crypto_queue *queue,
170 			   struct crypto_async_request *request);
171 void crypto_enqueue_request_head(struct crypto_queue *queue,
172 				 struct crypto_async_request *request);
173 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
174 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
175 {
176 	return queue->qlen;
177 }
178 
179 void crypto_inc(u8 *a, unsigned int size);
180 
181 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
182 {
183 	return tfm->__crt_ctx;
184 }
185 
186 static inline void *crypto_tfm_ctx_align(struct crypto_tfm *tfm,
187 					 unsigned int align)
188 {
189 	if (align <= crypto_tfm_ctx_alignment())
190 		align = 1;
191 
192 	return PTR_ALIGN(crypto_tfm_ctx(tfm), align);
193 }
194 
195 static inline unsigned int crypto_dma_align(void)
196 {
197 	return CRYPTO_DMA_ALIGN;
198 }
199 
200 static inline unsigned int crypto_dma_padding(void)
201 {
202 	return (crypto_dma_align() - 1) & ~(crypto_tfm_ctx_alignment() - 1);
203 }
204 
205 static inline void *crypto_tfm_ctx_dma(struct crypto_tfm *tfm)
206 {
207 	return crypto_tfm_ctx_align(tfm, crypto_dma_align());
208 }
209 
210 static inline struct crypto_instance *crypto_tfm_alg_instance(
211 	struct crypto_tfm *tfm)
212 {
213 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
214 }
215 
216 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
217 {
218 	return inst->__ctx;
219 }
220 
221 static inline struct crypto_async_request *crypto_get_backlog(
222 	struct crypto_queue *queue)
223 {
224 	return queue->backlog == &queue->list ? NULL :
225 	       container_of(queue->backlog, struct crypto_async_request, list);
226 }
227 
228 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
229 {
230 	return (algt->type ^ off) & algt->mask & off;
231 }
232 
233 /*
234  * When an algorithm uses another algorithm (e.g., if it's an instance of a
235  * template), these are the flags that should always be set on the "outer"
236  * algorithm if any "inner" algorithm has them set.
237  */
238 #define CRYPTO_ALG_INHERITED_FLAGS	\
239 	(CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |	\
240 	 CRYPTO_ALG_ALLOCATES_MEMORY)
241 
242 /*
243  * Given the type and mask that specify the flags restrictions on a template
244  * instance being created, return the mask that should be passed to
245  * crypto_grab_*() (along with type=0) to honor any request the user made to
246  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
247  */
248 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
249 {
250 	return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
251 }
252 
253 int crypto_register_notifier(struct notifier_block *nb);
254 int crypto_unregister_notifier(struct notifier_block *nb);
255 
256 /* Crypto notification events. */
257 enum {
258 	CRYPTO_MSG_ALG_REQUEST,
259 	CRYPTO_MSG_ALG_REGISTER,
260 	CRYPTO_MSG_ALG_LOADED,
261 };
262 
263 static inline void crypto_request_complete(struct crypto_async_request *req,
264 					   int err)
265 {
266 	req->complete(req->data, err);
267 }
268 
269 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
270 {
271 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
272 }
273 
274 #endif	/* _CRYPTO_ALGAPI_H */
275