xref: /openbmc/linux/include/crypto/algapi.h (revision b2765275)
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/crypto.h>
11 #include <linux/list.h>
12 #include <linux/kernel.h>
13 #include <linux/skbuff.h>
14 
15 /*
16  * Maximum values for blocksize and alignmask, used to allocate
17  * static buffers that are big enough for any combination of
18  * algs and architectures. Ciphers have a lower maximum size.
19  */
20 #define MAX_ALGAPI_BLOCKSIZE		160
21 #define MAX_ALGAPI_ALIGNMASK		63
22 #define MAX_CIPHER_BLOCKSIZE		16
23 #define MAX_CIPHER_ALIGNMASK		15
24 
25 struct crypto_aead;
26 struct crypto_instance;
27 struct module;
28 struct rtattr;
29 struct seq_file;
30 
31 struct crypto_type {
32 	unsigned int (*ctxsize)(struct crypto_alg *alg, u32 type, u32 mask);
33 	unsigned int (*extsize)(struct crypto_alg *alg);
34 	int (*init)(struct crypto_tfm *tfm, u32 type, u32 mask);
35 	int (*init_tfm)(struct crypto_tfm *tfm);
36 	void (*show)(struct seq_file *m, struct crypto_alg *alg);
37 	int (*report)(struct sk_buff *skb, struct crypto_alg *alg);
38 	void (*free)(struct crypto_instance *inst);
39 
40 	unsigned int type;
41 	unsigned int maskclear;
42 	unsigned int maskset;
43 	unsigned int tfmsize;
44 };
45 
46 struct crypto_instance {
47 	struct crypto_alg alg;
48 
49 	struct crypto_template *tmpl;
50 
51 	union {
52 		/* Node in list of instances after registration. */
53 		struct hlist_node list;
54 		/* List of attached spawns before registration. */
55 		struct crypto_spawn *spawns;
56 	};
57 
58 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
59 };
60 
61 struct crypto_template {
62 	struct list_head list;
63 	struct hlist_head instances;
64 	struct module *module;
65 
66 	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);
67 
68 	char name[CRYPTO_MAX_ALG_NAME];
69 };
70 
71 struct crypto_spawn {
72 	struct list_head list;
73 	struct crypto_alg *alg;
74 	union {
75 		/* Back pointer to instance after registration.*/
76 		struct crypto_instance *inst;
77 		/* Spawn list pointer prior to registration. */
78 		struct crypto_spawn *next;
79 	};
80 	const struct crypto_type *frontend;
81 	u32 mask;
82 	bool dead;
83 	bool registered;
84 };
85 
86 struct crypto_queue {
87 	struct list_head list;
88 	struct list_head *backlog;
89 
90 	unsigned int qlen;
91 	unsigned int max_qlen;
92 };
93 
94 struct scatter_walk {
95 	struct scatterlist *sg;
96 	unsigned int offset;
97 };
98 
99 void crypto_mod_put(struct crypto_alg *alg);
100 
101 int crypto_register_template(struct crypto_template *tmpl);
102 int crypto_register_templates(struct crypto_template *tmpls, int count);
103 void crypto_unregister_template(struct crypto_template *tmpl);
104 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
105 struct crypto_template *crypto_lookup_template(const char *name);
106 
107 int crypto_register_instance(struct crypto_template *tmpl,
108 			     struct crypto_instance *inst);
109 void crypto_unregister_instance(struct crypto_instance *inst);
110 
111 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
112 		      const char *name, u32 type, u32 mask);
113 void crypto_drop_spawn(struct crypto_spawn *spawn);
114 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
115 				    u32 mask);
116 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
117 
118 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
119 int crypto_check_attr_type(struct rtattr **tb, u32 type);
120 const char *crypto_attr_alg_name(struct rtattr *rta);
121 int crypto_attr_u32(struct rtattr *rta, u32 *num);
122 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
123 			struct crypto_alg *alg);
124 
125 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
126 int crypto_enqueue_request(struct crypto_queue *queue,
127 			   struct crypto_async_request *request);
128 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
129 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
130 {
131 	return queue->qlen;
132 }
133 
134 void crypto_inc(u8 *a, unsigned int size);
135 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int size);
136 
137 static inline void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
138 {
139 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
140 	    __builtin_constant_p(size) &&
141 	    (size % sizeof(unsigned long)) == 0) {
142 		unsigned long *d = (unsigned long *)dst;
143 		unsigned long *s = (unsigned long *)src;
144 
145 		while (size > 0) {
146 			*d++ ^= *s++;
147 			size -= sizeof(unsigned long);
148 		}
149 	} else {
150 		__crypto_xor(dst, dst, src, size);
151 	}
152 }
153 
154 static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2,
155 				  unsigned int size)
156 {
157 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
158 	    __builtin_constant_p(size) &&
159 	    (size % sizeof(unsigned long)) == 0) {
160 		unsigned long *d = (unsigned long *)dst;
161 		unsigned long *s1 = (unsigned long *)src1;
162 		unsigned long *s2 = (unsigned long *)src2;
163 
164 		while (size > 0) {
165 			*d++ = *s1++ ^ *s2++;
166 			size -= sizeof(unsigned long);
167 		}
168 	} else {
169 		__crypto_xor(dst, src1, src2, size);
170 	}
171 }
172 
173 static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm)
174 {
175 	return PTR_ALIGN(crypto_tfm_ctx(tfm),
176 			 crypto_tfm_alg_alignmask(tfm) + 1);
177 }
178 
179 static inline struct crypto_instance *crypto_tfm_alg_instance(
180 	struct crypto_tfm *tfm)
181 {
182 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
183 }
184 
185 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
186 {
187 	return inst->__ctx;
188 }
189 
190 struct crypto_cipher_spawn {
191 	struct crypto_spawn base;
192 };
193 
194 static inline int crypto_grab_cipher(struct crypto_cipher_spawn *spawn,
195 				     struct crypto_instance *inst,
196 				     const char *name, u32 type, u32 mask)
197 {
198 	type &= ~CRYPTO_ALG_TYPE_MASK;
199 	type |= CRYPTO_ALG_TYPE_CIPHER;
200 	mask |= CRYPTO_ALG_TYPE_MASK;
201 	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
202 }
203 
204 static inline void crypto_drop_cipher(struct crypto_cipher_spawn *spawn)
205 {
206 	crypto_drop_spawn(&spawn->base);
207 }
208 
209 static inline struct crypto_alg *crypto_spawn_cipher_alg(
210 	struct crypto_cipher_spawn *spawn)
211 {
212 	return spawn->base.alg;
213 }
214 
215 static inline struct crypto_cipher *crypto_spawn_cipher(
216 	struct crypto_cipher_spawn *spawn)
217 {
218 	u32 type = CRYPTO_ALG_TYPE_CIPHER;
219 	u32 mask = CRYPTO_ALG_TYPE_MASK;
220 
221 	return __crypto_cipher_cast(crypto_spawn_tfm(&spawn->base, type, mask));
222 }
223 
224 static inline struct cipher_alg *crypto_cipher_alg(struct crypto_cipher *tfm)
225 {
226 	return &crypto_cipher_tfm(tfm)->__crt_alg->cra_cipher;
227 }
228 
229 static inline struct crypto_async_request *crypto_get_backlog(
230 	struct crypto_queue *queue)
231 {
232 	return queue->backlog == &queue->list ? NULL :
233 	       container_of(queue->backlog, struct crypto_async_request, list);
234 }
235 
236 static inline int crypto_requires_off(u32 type, u32 mask, u32 off)
237 {
238 	return (type ^ off) & mask & off;
239 }
240 
241 /*
242  * Returns CRYPTO_ALG_ASYNC if type/mask requires the use of sync algorithms.
243  * Otherwise returns zero.
244  */
245 static inline int crypto_requires_sync(u32 type, u32 mask)
246 {
247 	return crypto_requires_off(type, mask, CRYPTO_ALG_ASYNC);
248 }
249 
250 noinline unsigned long __crypto_memneq(const void *a, const void *b, size_t size);
251 
252 /**
253  * crypto_memneq - Compare two areas of memory without leaking
254  *		   timing information.
255  *
256  * @a: One area of memory
257  * @b: Another area of memory
258  * @size: The size of the area.
259  *
260  * Returns 0 when data is equal, 1 otherwise.
261  */
262 static inline int crypto_memneq(const void *a, const void *b, size_t size)
263 {
264 	return __crypto_memneq(a, b, size) != 0UL ? 1 : 0;
265 }
266 
267 static inline void crypto_yield(u32 flags)
268 {
269 	if (flags & CRYPTO_TFM_REQ_MAY_SLEEP)
270 		cond_resched();
271 }
272 
273 int crypto_register_notifier(struct notifier_block *nb);
274 int crypto_unregister_notifier(struct notifier_block *nb);
275 
276 /* Crypto notification events. */
277 enum {
278 	CRYPTO_MSG_ALG_REQUEST,
279 	CRYPTO_MSG_ALG_REGISTER,
280 	CRYPTO_MSG_ALG_LOADED,
281 };
282 
283 #endif	/* _CRYPTO_ALGAPI_H */
284