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 
14 /*
15  * Maximum values for blocksize and alignmask, used to allocate
16  * static buffers that are big enough for any combination of
17  * algs and architectures. Ciphers have a lower maximum size.
18  */
19 #define MAX_ALGAPI_BLOCKSIZE		160
20 #define MAX_ALGAPI_ALIGNMASK		63
21 #define MAX_CIPHER_BLOCKSIZE		16
22 #define MAX_CIPHER_ALIGNMASK		15
23 
24 struct crypto_aead;
25 struct crypto_instance;
26 struct module;
27 struct rtattr;
28 struct seq_file;
29 struct sk_buff;
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 struct crypto_attr_alg {
100 	char name[CRYPTO_MAX_ALG_NAME];
101 };
102 
103 struct crypto_attr_type {
104 	u32 type;
105 	u32 mask;
106 };
107 
108 void crypto_mod_put(struct crypto_alg *alg);
109 
110 int crypto_register_template(struct crypto_template *tmpl);
111 int crypto_register_templates(struct crypto_template *tmpls, int count);
112 void crypto_unregister_template(struct crypto_template *tmpl);
113 void crypto_unregister_templates(struct crypto_template *tmpls, int count);
114 struct crypto_template *crypto_lookup_template(const char *name);
115 
116 int crypto_register_instance(struct crypto_template *tmpl,
117 			     struct crypto_instance *inst);
118 void crypto_unregister_instance(struct crypto_instance *inst);
119 
120 int crypto_grab_spawn(struct crypto_spawn *spawn, struct crypto_instance *inst,
121 		      const char *name, u32 type, u32 mask);
122 void crypto_drop_spawn(struct crypto_spawn *spawn);
123 struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type,
124 				    u32 mask);
125 void *crypto_spawn_tfm2(struct crypto_spawn *spawn);
126 
127 struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb);
128 int crypto_check_attr_type(struct rtattr **tb, u32 type, u32 *mask_ret);
129 const char *crypto_attr_alg_name(struct rtattr *rta);
130 int crypto_inst_setname(struct crypto_instance *inst, const char *name,
131 			struct crypto_alg *alg);
132 
133 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
134 int crypto_enqueue_request(struct crypto_queue *queue,
135 			   struct crypto_async_request *request);
136 void crypto_enqueue_request_head(struct crypto_queue *queue,
137 				 struct crypto_async_request *request);
138 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
crypto_queue_len(struct crypto_queue * queue)139 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
140 {
141 	return queue->qlen;
142 }
143 
144 void crypto_inc(u8 *a, unsigned int size);
145 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int size);
146 
crypto_xor(u8 * dst,const u8 * src,unsigned int size)147 static inline void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
148 {
149 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
150 	    __builtin_constant_p(size) &&
151 	    (size % sizeof(unsigned long)) == 0) {
152 		unsigned long *d = (unsigned long *)dst;
153 		unsigned long *s = (unsigned long *)src;
154 
155 		while (size > 0) {
156 			*d++ ^= *s++;
157 			size -= sizeof(unsigned long);
158 		}
159 	} else {
160 		__crypto_xor(dst, dst, src, size);
161 	}
162 }
163 
crypto_xor_cpy(u8 * dst,const u8 * src1,const u8 * src2,unsigned int size)164 static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2,
165 				  unsigned int size)
166 {
167 	if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
168 	    __builtin_constant_p(size) &&
169 	    (size % sizeof(unsigned long)) == 0) {
170 		unsigned long *d = (unsigned long *)dst;
171 		unsigned long *s1 = (unsigned long *)src1;
172 		unsigned long *s2 = (unsigned long *)src2;
173 
174 		while (size > 0) {
175 			*d++ = *s1++ ^ *s2++;
176 			size -= sizeof(unsigned long);
177 		}
178 	} else {
179 		__crypto_xor(dst, src1, src2, size);
180 	}
181 }
182 
crypto_tfm_ctx_aligned(struct crypto_tfm * tfm)183 static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm)
184 {
185 	return PTR_ALIGN(crypto_tfm_ctx(tfm),
186 			 crypto_tfm_alg_alignmask(tfm) + 1);
187 }
188 
crypto_tfm_alg_instance(struct crypto_tfm * tfm)189 static inline struct crypto_instance *crypto_tfm_alg_instance(
190 	struct crypto_tfm *tfm)
191 {
192 	return container_of(tfm->__crt_alg, struct crypto_instance, alg);
193 }
194 
crypto_instance_ctx(struct crypto_instance * inst)195 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
196 {
197 	return inst->__ctx;
198 }
199 
crypto_get_backlog(struct crypto_queue * queue)200 static inline struct crypto_async_request *crypto_get_backlog(
201 	struct crypto_queue *queue)
202 {
203 	return queue->backlog == &queue->list ? NULL :
204 	       container_of(queue->backlog, struct crypto_async_request, list);
205 }
206 
crypto_requires_off(struct crypto_attr_type * algt,u32 off)207 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
208 {
209 	return (algt->type ^ off) & algt->mask & off;
210 }
211 
212 /*
213  * When an algorithm uses another algorithm (e.g., if it's an instance of a
214  * template), these are the flags that should always be set on the "outer"
215  * algorithm if any "inner" algorithm has them set.
216  */
217 #define CRYPTO_ALG_INHERITED_FLAGS	\
218 	(CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |	\
219 	 CRYPTO_ALG_ALLOCATES_MEMORY)
220 
221 /*
222  * Given the type and mask that specify the flags restrictions on a template
223  * instance being created, return the mask that should be passed to
224  * crypto_grab_*() (along with type=0) to honor any request the user made to
225  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
226  */
crypto_algt_inherited_mask(struct crypto_attr_type * algt)227 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
228 {
229 	return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
230 }
231 
232 noinline unsigned long __crypto_memneq(const void *a, const void *b, size_t size);
233 
234 /**
235  * crypto_memneq - Compare two areas of memory without leaking
236  *		   timing information.
237  *
238  * @a: One area of memory
239  * @b: Another area of memory
240  * @size: The size of the area.
241  *
242  * Returns 0 when data is equal, 1 otherwise.
243  */
crypto_memneq(const void * a,const void * b,size_t size)244 static inline int crypto_memneq(const void *a, const void *b, size_t size)
245 {
246 	return __crypto_memneq(a, b, size) != 0UL ? 1 : 0;
247 }
248 
249 int crypto_register_notifier(struct notifier_block *nb);
250 int crypto_unregister_notifier(struct notifier_block *nb);
251 
252 /* Crypto notification events. */
253 enum {
254 	CRYPTO_MSG_ALG_REQUEST,
255 	CRYPTO_MSG_ALG_REGISTER,
256 	CRYPTO_MSG_ALG_LOADED,
257 };
258 
259 #endif	/* _CRYPTO_ALGAPI_H */
260