xref: /linux/include/crypto/algapi.h (revision 0e9b70c1e3623fa110fb6be553e644524228ef60)
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 <linux/align.h>
11 #include <linux/cache.h>
12 #include <linux/crypto.h>
13 #include <linux/kconfig.h>
14 #include <linux/list.h>
15 #include <linux/types.h>
16 
17 #include <asm/unaligned.h>
18 
19 /*
20  * Maximum values for blocksize and alignmask, used to allocate
21  * static buffers that are big enough for any combination of
22  * algs and architectures. Ciphers have a lower maximum size.
23  */
24 #define MAX_ALGAPI_BLOCKSIZE		160
25 #define MAX_ALGAPI_ALIGNMASK		127
26 #define MAX_CIPHER_BLOCKSIZE		16
27 #define MAX_CIPHER_ALIGNMASK		15
28 
29 #ifdef ARCH_DMA_MINALIGN
30 #define CRYPTO_DMA_ALIGN ARCH_DMA_MINALIGN
31 #else
32 #define CRYPTO_DMA_ALIGN CRYPTO_MINALIGN
33 #endif
34 
35 #define CRYPTO_DMA_PADDING ((CRYPTO_DMA_ALIGN - 1) & ~(CRYPTO_MINALIGN - 1))
36 
37 struct crypto_aead;
38 struct crypto_instance;
39 struct module;
40 struct notifier_block;
41 struct rtattr;
42 struct seq_file;
43 struct sk_buff;
44 
45 struct crypto_type {
46 	unsigned int (*ctxsize)(struct crypto_alg *alg, u32 type, u32 mask);
47 	unsigned int (*extsize)(struct crypto_alg *alg);
48 	int (*init)(struct crypto_tfm *tfm, u32 type, u32 mask);
49 	int (*init_tfm)(struct crypto_tfm *tfm);
50 	void (*show)(struct seq_file *m, struct crypto_alg *alg);
51 	int (*report)(struct sk_buff *skb, struct crypto_alg *alg);
52 	void (*free)(struct crypto_instance *inst);
53 
54 	unsigned int type;
55 	unsigned int maskclear;
56 	unsigned int maskset;
57 	unsigned int tfmsize;
58 };
59 
60 struct crypto_instance {
61 	struct crypto_alg alg;
62 
63 	struct crypto_template *tmpl;
64 
65 	union {
66 		/* Node in list of instances after registration. */
67 		struct hlist_node list;
68 		/* List of attached spawns before registration. */
69 		struct crypto_spawn *spawns;
70 	};
71 
72 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
73 };
74 
75 struct crypto_template {
76 	struct list_head list;
77 	struct hlist_head instances;
78 	struct module *module;
79 
80 	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);
81 
82 	char name[CRYPTO_MAX_ALG_NAME];
83 };
84 
85 struct crypto_spawn {
86 	struct list_head list;
87 	struct crypto_alg *alg;
88 	union {
89 		/* Back pointer to instance after registration.*/
90 		struct crypto_instance *inst;
91 		/* Spawn list pointer prior to registration. */
92 		struct crypto_spawn *next;
93 	};
94 	const struct crypto_type *frontend;
95 	u32 mask;
96 	bool dead;
97 	bool registered;
98 };
99 
100 struct crypto_queue {
101 	struct list_head list;
102 	struct list_head *backlog;
103 
104 	unsigned int qlen;
105 	unsigned int max_qlen;
106 };
107 
108 struct scatter_walk {
109 	struct scatterlist *sg;
110 	unsigned int offset;
111 };
112 
113 struct crypto_attr_alg {
114 	char name[CRYPTO_MAX_ALG_NAME];
115 };
116 
117 struct crypto_attr_type {
118 	u32 type;
119 	u32 mask;
120 };
121 
122 void crypto_mod_put(struct crypto_alg *alg);
123 
124 int crypto_register_template(struct crypto_template *tmpl);
125 int crypto_register_templates(struct crypto_template *tmpls, int count);
126 void crypto_unregister_template(struct crypto_template *tmpl);
127 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
128 struct crypto_template *crypto_lookup_template(const char *name);
129 
130 int crypto_register_instance(struct crypto_template *tmpl,
131 			     struct crypto_instance *inst);
132 void crypto_unregister_instance(struct crypto_instance *inst);
133 
134 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
135 		      const char *name, u32 type, u32 mask);
136 void crypto_drop_spawn(struct crypto_spawn *spawn);
137 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
138 				    u32 mask);
139 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
140 
141 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
142 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
143 const char *crypto_attr_alg_name(struct rtattr *rta);
144 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
145 			struct crypto_alg *alg);
146 
147 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
148 int crypto_enqueue_request(struct crypto_queue *queue,
149 			   struct crypto_async_request *request);
150 void crypto_enqueue_request_head(struct crypto_queue *queue,
151 				 struct crypto_async_request *request);
152 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
153 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
154 {
155 	return queue->qlen;
156 }
157 
158 void crypto_inc(u8 *a, unsigned int size);
159 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int size);
160 
161 static inline void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
162 {
163 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
164 	    __builtin_constant_p(size) &&
165 	    (size % sizeof(unsigned long)) == 0) {
166 		unsigned long *d = (unsigned long *)dst;
167 		unsigned long *s = (unsigned long *)src;
168 		unsigned long l;
169 
170 		while (size > 0) {
171 			l = get_unaligned(d) ^ get_unaligned(s++);
172 			put_unaligned(l, d++);
173 			size -= sizeof(unsigned long);
174 		}
175 	} else {
176 		__crypto_xor(dst, dst, src, size);
177 	}
178 }
179 
180 static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2,
181 				  unsigned int size)
182 {
183 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
184 	    __builtin_constant_p(size) &&
185 	    (size % sizeof(unsigned long)) == 0) {
186 		unsigned long *d = (unsigned long *)dst;
187 		unsigned long *s1 = (unsigned long *)src1;
188 		unsigned long *s2 = (unsigned long *)src2;
189 		unsigned long l;
190 
191 		while (size > 0) {
192 			l = get_unaligned(s1++) ^ get_unaligned(s2++);
193 			put_unaligned(l, d++);
194 			size -= sizeof(unsigned long);
195 		}
196 	} else {
197 		__crypto_xor(dst, src1, src2, size);
198 	}
199 }
200 
201 static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm)
202 {
203 	return tfm->__crt_ctx;
204 }
205 
206 static inline void *crypto_tfm_ctx_align(struct crypto_tfm *tfm,
207 					 unsigned int align)
208 {
209 	if (align <= crypto_tfm_ctx_alignment())
210 		align = 1;
211 
212 	return PTR_ALIGN(crypto_tfm_ctx(tfm), align);
213 }
214 
215 static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm)
216 {
217 	return crypto_tfm_ctx_align(tfm, crypto_tfm_alg_alignmask(tfm) + 1);
218 }
219 
220 static inline unsigned int crypto_dma_align(void)
221 {
222 	return CRYPTO_DMA_ALIGN;
223 }
224 
225 static inline unsigned int crypto_dma_padding(void)
226 {
227 	return (crypto_dma_align() - 1) & ~(crypto_tfm_ctx_alignment() - 1);
228 }
229 
230 static inline void *crypto_tfm_ctx_dma(struct crypto_tfm *tfm)
231 {
232 	return crypto_tfm_ctx_align(tfm, crypto_dma_align());
233 }
234 
235 static inline struct crypto_instance *crypto_tfm_alg_instance(
236 	struct crypto_tfm *tfm)
237 {
238 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
239 }
240 
241 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
242 {
243 	return inst->__ctx;
244 }
245 
246 static inline struct crypto_async_request *crypto_get_backlog(
247 	struct crypto_queue *queue)
248 {
249 	return queue->backlog == &queue->list ? NULL :
250 	       container_of(queue->backlog, struct crypto_async_request, list);
251 }
252 
253 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
254 {
255 	return (algt->type ^ off) & algt->mask & off;
256 }
257 
258 /*
259  * When an algorithm uses another algorithm (e.g., if it's an instance of a
260  * template), these are the flags that should always be set on the "outer"
261  * algorithm if any "inner" algorithm has them set.
262  */
263 #define CRYPTO_ALG_INHERITED_FLAGS	\
264 	(CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |	\
265 	 CRYPTO_ALG_ALLOCATES_MEMORY)
266 
267 /*
268  * Given the type and mask that specify the flags restrictions on a template
269  * instance being created, return the mask that should be passed to
270  * crypto_grab_*() (along with type=0) to honor any request the user made to
271  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
272  */
273 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
274 {
275 	return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
276 }
277 
278 noinline unsigned long __crypto_memneq(const void *a, const void *b, size_t size);
279 
280 /**
281  * crypto_memneq - Compare two areas of memory without leaking
282  *		   timing information.
283  *
284  * @a: One area of memory
285  * @b: Another area of memory
286  * @size: The size of the area.
287  *
288  * Returns 0 when data is equal, 1 otherwise.
289  */
290 static inline int crypto_memneq(const void *a, const void *b, size_t size)
291 {
292 	return __crypto_memneq(a, b, size) != 0UL ? 1 : 0;
293 }
294 
295 int crypto_register_notifier(struct notifier_block *nb);
296 int crypto_unregister_notifier(struct notifier_block *nb);
297 
298 /* Crypto notification events. */
299 enum {
300 	CRYPTO_MSG_ALG_REQUEST,
301 	CRYPTO_MSG_ALG_REGISTER,
302 	CRYPTO_MSG_ALG_LOADED,
303 };
304 
305 static inline void crypto_request_complete(struct crypto_async_request *req,
306 					   int err)
307 {
308 	req->complete(req->data, err);
309 }
310 
311 #endif	/* _CRYPTO_ALGAPI_H */
312