xref: /openbmc/linux/include/crypto/algapi.h (revision 34fa67e7)
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/crypto.h>
12 #include <linux/kconfig.h>
13 #include <linux/list.h>
14 #include <linux/types.h>
15 
16 /*
17  * Maximum values for blocksize and alignmask, used to allocate
18  * static buffers that are big enough for any combination of
19  * algs and architectures. Ciphers have a lower maximum size.
20  */
21 #define MAX_ALGAPI_BLOCKSIZE		160
22 #define MAX_ALGAPI_ALIGNMASK		63
23 #define MAX_CIPHER_BLOCKSIZE		16
24 #define MAX_CIPHER_ALIGNMASK		15
25 
26 struct crypto_aead;
27 struct crypto_instance;
28 struct module;
29 struct notifier_block;
30 struct rtattr;
31 struct seq_file;
32 struct sk_buff;
33 
34 struct crypto_type {
35 	unsigned int (*ctxsize)(struct crypto_alg *alg, u32 type, u32 mask);
36 	unsigned int (*extsize)(struct crypto_alg *alg);
37 	int (*init)(struct crypto_tfm *tfm, u32 type, u32 mask);
38 	int (*init_tfm)(struct crypto_tfm *tfm);
39 	void (*show)(struct seq_file *m, struct crypto_alg *alg);
40 	int (*report)(struct sk_buff *skb, struct crypto_alg *alg);
41 	void (*free)(struct crypto_instance *inst);
42 
43 	unsigned int type;
44 	unsigned int maskclear;
45 	unsigned int maskset;
46 	unsigned int tfmsize;
47 };
48 
49 struct crypto_instance {
50 	struct crypto_alg alg;
51 
52 	struct crypto_template *tmpl;
53 
54 	union {
55 		/* Node in list of instances after registration. */
56 		struct hlist_node list;
57 		/* List of attached spawns before registration. */
58 		struct crypto_spawn *spawns;
59 	};
60 
61 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
62 };
63 
64 struct crypto_template {
65 	struct list_head list;
66 	struct hlist_head instances;
67 	struct module *module;
68 
69 	int (*create)(struct crypto_template *tmpl, struct rtattr **tb);
70 
71 	char name[CRYPTO_MAX_ALG_NAME];
72 };
73 
74 struct crypto_spawn {
75 	struct list_head list;
76 	struct crypto_alg *alg;
77 	union {
78 		/* Back pointer to instance after registration.*/
79 		struct crypto_instance *inst;
80 		/* Spawn list pointer prior to registration. */
81 		struct crypto_spawn *next;
82 	};
83 	const struct crypto_type *frontend;
84 	u32 mask;
85 	bool dead;
86 	bool registered;
87 };
88 
89 struct crypto_queue {
90 	struct list_head list;
91 	struct list_head *backlog;
92 
93 	unsigned int qlen;
94 	unsigned int max_qlen;
95 };
96 
97 struct scatter_walk {
98 	struct scatterlist *sg;
99 	unsigned int offset;
100 };
101 
102 struct crypto_attr_alg {
103 	char name[CRYPTO_MAX_ALG_NAME];
104 };
105 
106 struct crypto_attr_type {
107 	u32 type;
108 	u32 mask;
109 };
110 
111 void crypto_mod_put(struct crypto_alg *alg);
112 
113 int crypto_register_template(struct crypto_template *tmpl);
114 int crypto_register_templates(struct crypto_template *tmpls, int count);
115 void crypto_unregister_template(struct crypto_template *tmpl);
116 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
117 struct crypto_template *crypto_lookup_template(const char *name);
118 
119 int crypto_register_instance(struct crypto_template *tmpl,
120 			     struct crypto_instance *inst);
121 void crypto_unregister_instance(struct crypto_instance *inst);
122 
123 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
124 		      const char *name, u32 type, u32 mask);
125 void crypto_drop_spawn(struct crypto_spawn *spawn);
126 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
127 				    u32 mask);
128 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
129 
130 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
131 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
132 const char *crypto_attr_alg_name(struct rtattr *rta);
133 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
134 			struct crypto_alg *alg);
135 
136 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
137 int crypto_enqueue_request(struct crypto_queue *queue,
138 			   struct crypto_async_request *request);
139 void crypto_enqueue_request_head(struct crypto_queue *queue,
140 				 struct crypto_async_request *request);
141 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
142 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
143 {
144 	return queue->qlen;
145 }
146 
147 void crypto_inc(u8 *a, unsigned int size);
148 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int size);
149 
150 static inline void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
151 {
152 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
153 	    __builtin_constant_p(size) &&
154 	    (size % sizeof(unsigned long)) == 0) {
155 		unsigned long *d = (unsigned long *)dst;
156 		unsigned long *s = (unsigned long *)src;
157 
158 		while (size > 0) {
159 			*d++ ^= *s++;
160 			size -= sizeof(unsigned long);
161 		}
162 	} else {
163 		__crypto_xor(dst, dst, src, size);
164 	}
165 }
166 
167 static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2,
168 				  unsigned int size)
169 {
170 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
171 	    __builtin_constant_p(size) &&
172 	    (size % sizeof(unsigned long)) == 0) {
173 		unsigned long *d = (unsigned long *)dst;
174 		unsigned long *s1 = (unsigned long *)src1;
175 		unsigned long *s2 = (unsigned long *)src2;
176 
177 		while (size > 0) {
178 			*d++ = *s1++ ^ *s2++;
179 			size -= sizeof(unsigned long);
180 		}
181 	} else {
182 		__crypto_xor(dst, src1, src2, size);
183 	}
184 }
185 
186 static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm)
187 {
188 	return PTR_ALIGN(crypto_tfm_ctx(tfm),
189 			 crypto_tfm_alg_alignmask(tfm) + 1);
190 }
191 
192 static inline struct crypto_instance *crypto_tfm_alg_instance(
193 	struct crypto_tfm *tfm)
194 {
195 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
196 }
197 
198 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
199 {
200 	return inst->__ctx;
201 }
202 
203 static inline struct crypto_async_request *crypto_get_backlog(
204 	struct crypto_queue *queue)
205 {
206 	return queue->backlog == &queue->list ? NULL :
207 	       container_of(queue->backlog, struct crypto_async_request, list);
208 }
209 
210 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
211 {
212 	return (algt->type ^ off) & algt->mask & off;
213 }
214 
215 /*
216  * When an algorithm uses another algorithm (e.g., if it's an instance of a
217  * template), these are the flags that should always be set on the "outer"
218  * algorithm if any "inner" algorithm has them set.
219  */
220 #define CRYPTO_ALG_INHERITED_FLAGS	\
221 	(CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |	\
222 	 CRYPTO_ALG_ALLOCATES_MEMORY)
223 
224 /*
225  * Given the type and mask that specify the flags restrictions on a template
226  * instance being created, return the mask that should be passed to
227  * crypto_grab_*() (along with type=0) to honor any request the user made to
228  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
229  */
230 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
231 {
232 	return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
233 }
234 
235 noinline unsigned long __crypto_memneq(const void *a, const void *b, size_t size);
236 
237 /**
238  * crypto_memneq - Compare two areas of memory without leaking
239  *		   timing information.
240  *
241  * @a: One area of memory
242  * @b: Another area of memory
243  * @size: The size of the area.
244  *
245  * Returns 0 when data is equal, 1 otherwise.
246  */
247 static inline int crypto_memneq(const void *a, const void *b, size_t size)
248 {
249 	return __crypto_memneq(a, b, size) != 0UL ? 1 : 0;
250 }
251 
252 int crypto_register_notifier(struct notifier_block *nb);
253 int crypto_unregister_notifier(struct notifier_block *nb);
254 
255 /* Crypto notification events. */
256 enum {
257 	CRYPTO_MSG_ALG_REQUEST,
258 	CRYPTO_MSG_ALG_REGISTER,
259 	CRYPTO_MSG_ALG_LOADED,
260 };
261 
262 #endif	/* _CRYPTO_ALGAPI_H */
263