include/crypto/algapi.h

   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 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, u32 *mask_ret);
 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 void crypto_enqueue_request_head(struct crypto_queue *queue,
 129                                  struct crypto_async_request *request);
 130 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
 131 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
 132 {
 133         return queue->qlen;
 134 }
 135
 136 void crypto_inc(u8 *a, unsigned int size);
 137 void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int size);
 138
 139 static inline void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
 140 {
 141         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
 142             __builtin_constant_p(size) &&
 143             (size % sizeof(unsigned long)) == 0) {
 144                 unsigned long *d = (unsigned long *)dst;
 145                 unsigned long *s = (unsigned long *)src;
 146
 147                 while (size > 0) {
 148                         *d++ ^= *s++;
 149                         size -= sizeof(unsigned long);
 150                 }
 151         } else {
 152                 __crypto_xor(dst, dst, src, size);
 153         }
 154 }
 155
 156 static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2,
 157                                   unsigned int size)
 158 {
 159         if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
 160             __builtin_constant_p(size) &&
 161             (size % sizeof(unsigned long)) == 0) {
 162                 unsigned long *d = (unsigned long *)dst;
 163                 unsigned long *s1 = (unsigned long *)src1;
 164                 unsigned long *s2 = (unsigned long *)src2;
 165
 166                 while (size > 0) {
 167                         *d++ = *s1++ ^ *s2++;
 168                         size -= sizeof(unsigned long);
 169                 }
 170         } else {
 171                 __crypto_xor(dst, src1, src2, size);
 172         }
 173 }
 174
 175 static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm)
 176 {
 177         return PTR_ALIGN(crypto_tfm_ctx(tfm),
 178                          crypto_tfm_alg_alignmask(tfm) + 1);
 179 }
 180
 181 static inline struct crypto_instance *crypto_tfm_alg_instance(
 182         struct crypto_tfm *tfm)
 183 {
 184         return container_of(tfm->__crt_alg, struct crypto_instance, alg);
 185 }
 186
 187 static inline void *crypto_instance_ctx(struct crypto_instance *inst)
 188 {
 189         return inst->__ctx;
 190 }
 191
 192 struct crypto_cipher_spawn {
 193         struct crypto_spawn base;
 194 };
 195
 196 static inline int crypto_grab_cipher(struct crypto_cipher_spawn *spawn,
 197                                      struct crypto_instance *inst,
 198                                      const char *name, u32 type, u32 mask)
 199 {
 200         type &= ~CRYPTO_ALG_TYPE_MASK;
 201         type |= CRYPTO_ALG_TYPE_CIPHER;
 202         mask |= CRYPTO_ALG_TYPE_MASK;
 203         return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
 204 }
 205
 206 static inline void crypto_drop_cipher(struct crypto_cipher_spawn *spawn)
 207 {
 208         crypto_drop_spawn(&spawn->base);
 209 }
 210
 211 static inline struct crypto_alg *crypto_spawn_cipher_alg(
 212         struct crypto_cipher_spawn *spawn)
 213 {
 214         return spawn->base.alg;
 215 }
 216
 217 static inline struct crypto_cipher *crypto_spawn_cipher(
 218         struct crypto_cipher_spawn *spawn)
 219 {
 220         u32 type = CRYPTO_ALG_TYPE_CIPHER;
 221         u32 mask = CRYPTO_ALG_TYPE_MASK;
 222
 223         return __crypto_cipher_cast(crypto_spawn_tfm(&spawn->base, type, mask));
 224 }
 225
 226 static inline struct cipher_alg *crypto_cipher_alg(struct crypto_cipher *tfm)
 227 {
 228         return &crypto_cipher_tfm(tfm)->__crt_alg->cra_cipher;
 229 }
 230
 231 static inline struct crypto_async_request *crypto_get_backlog(
 232         struct crypto_queue *queue)
 233 {
 234         return queue->backlog == &queue->list ? NULL :
 235                container_of(queue->backlog, struct crypto_async_request, list);
 236 }
 237
 238 static inline u32 crypto_requires_off(struct crypto_attr_type *algt, u32 off)
 239 {
 240         return (algt->type ^ off) & algt->mask & off;
 241 }
 242
 243 /*
 244  * When an algorithm uses another algorithm (e.g., if it's an instance of a
 245  * template), these are the flags that should always be set on the "outer"
 246  * algorithm if any "inner" algorithm has them set.
 247  */
 248 #define CRYPTO_ALG_INHERITED_FLAGS      \
 249         (CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK |  \
 250          CRYPTO_ALG_ALLOCATES_MEMORY)
 251
 252 /*
 253  * Given the type and mask that specify the flags restrictions on a template
 254  * instance being created, return the mask that should be passed to
 255  * crypto_grab_*() (along with type=0) to honor any request the user made to
 256  * have any of the CRYPTO_ALG_INHERITED_FLAGS clear.
 257  */
 258 static inline u32 crypto_algt_inherited_mask(struct crypto_attr_type *algt)
 259 {
 260         return crypto_requires_off(algt, CRYPTO_ALG_INHERITED_FLAGS);
 261 }
 262
 263 noinline unsigned long __crypto_memneq(const void *a, const void *b, size_t size);
 264
 265 /**
 266  * crypto_memneq - Compare two areas of memory without leaking
 267  *                 timing information.
 268  *
 269  * @a: One area of memory
 270  * @b: Another area of memory
 271  * @size: The size of the area.
 272  *
 273  * Returns 0 when data is equal, 1 otherwise.
 274  */
 275 static inline int crypto_memneq(const void *a, const void *b, size_t size)
 276 {
 277         return __crypto_memneq(a, b, size) != 0UL ? 1 : 0;
 278 }
 279
 280 int crypto_register_notifier(struct notifier_block *nb);
 281 int crypto_unregister_notifier(struct notifier_block *nb);
 282
 283 /* Crypto notification events. */
 284 enum {
 285         CRYPTO_MSG_ALG_REQUEST,
 286         CRYPTO_MSG_ALG_REGISTER,
 287         CRYPTO_MSG_ALG_LOADED,
 288 };
 289
 290 #endif  /* _CRYPTO_ALGAPI_H */