linux/include/crypto/internal/skcipher.h

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/*
* Symmetric key ciphers.
*
* Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#ifndef _CRYPTO_INTERNAL_SKCIPHER_H
#define _CRYPTO_INTERNAL_SKCIPHER_H
#include <crypto/algapi.h>
[CRYPTO] skcipher: Add givcrypt operations and givcipher type Different block cipher modes have different requirements for intialisation vectors. For example, CBC can use a simple randomly generated IV while modes such as CTR must use an IV generation mechanisms that give a stronger guarantee on the lack of collisions. Furthermore, disk encryption modes have their own IV generation algorithms. Up until now IV generation has been left to the users of the symmetric key cipher API. This is inconvenient as the number of block cipher modes increase because the user needs to be aware of which mode is supposed to be paired with which IV generation algorithm. Therefore it makes sense to integrate the IV generation into the crypto API. This patch takes the first step in that direction by creating two new ablkcipher operations, givencrypt and givdecrypt that generates an IV before performing the actual encryption or decryption. The operations are currently not exposed to the user. That will be done once the underlying functionality has actually been implemented. It also creates the underlying givcipher type. Algorithms that directly generate IVs would use it instead of ablkcipher. All other algorithms (including all existing ones) would generate a givcipher algorithm upon registration. This givcipher algorithm will be constructed from the geniv string that's stored in every algorithm. That string will locate a template which is instantiated by the blkcipher/ablkcipher algorithm in question to give a givcipher algorithm. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-12-17 13:51:27 +00:00
#include <crypto/skcipher.h>
#include <linux/list.h>
#include <linux/types.h>
struct aead_request;
struct rtattr;
struct skcipher_instance {
void (*free)(struct skcipher_instance *inst);
union {
struct {
char head[offsetof(struct skcipher_alg, base)];
struct crypto_instance base;
} s;
struct skcipher_alg alg;
};
};
struct crypto_skcipher_spawn {
struct crypto_spawn base;
};
struct skcipher_walk {
union {
struct {
struct page *page;
unsigned long offset;
} phys;
struct {
u8 *page;
void *addr;
} virt;
} src, dst;
struct scatter_walk in;
unsigned int nbytes;
struct scatter_walk out;
unsigned int total;
struct list_head buffers;
u8 *page;
u8 *buffer;
u8 *oiv;
void *iv;
unsigned int ivsize;
int flags;
unsigned int blocksize;
unsigned int stride;
unsigned int alignmask;
};
static inline struct crypto_instance *skcipher_crypto_instance(
struct skcipher_instance *inst)
{
return &inst->s.base;
}
static inline struct skcipher_instance *skcipher_alg_instance(
struct crypto_skcipher *skcipher)
{
return container_of(crypto_skcipher_alg(skcipher),
struct skcipher_instance, alg);
}
static inline void *skcipher_instance_ctx(struct skcipher_instance *inst)
{
return crypto_instance_ctx(skcipher_crypto_instance(inst));
}
static inline void skcipher_request_complete(struct skcipher_request *req, int err)
{
req->base.complete(&req->base, err);
}
static inline void crypto_set_skcipher_spawn(
struct crypto_skcipher_spawn *spawn, struct crypto_instance *inst)
{
crypto_set_spawn(&spawn->base, inst);
}
int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name,
u32 type, u32 mask);
static inline void crypto_drop_skcipher(struct crypto_skcipher_spawn *spawn)
{
crypto_drop_spawn(&spawn->base);
}
static inline struct skcipher_alg *crypto_skcipher_spawn_alg(
struct crypto_skcipher_spawn *spawn)
{
return container_of(spawn->base.alg, struct skcipher_alg, base);
}
static inline struct skcipher_alg *crypto_spawn_skcipher_alg(
struct crypto_skcipher_spawn *spawn)
{
return crypto_skcipher_spawn_alg(spawn);
}
static inline struct crypto_skcipher *crypto_spawn_skcipher(
struct crypto_skcipher_spawn *spawn)
{
return crypto_spawn_tfm2(&spawn->base);
}
static inline void crypto_skcipher_set_reqsize(
struct crypto_skcipher *skcipher, unsigned int reqsize)
{
skcipher->reqsize = reqsize;
}
int crypto_register_skcipher(struct skcipher_alg *alg);
void crypto_unregister_skcipher(struct skcipher_alg *alg);
int crypto_register_skciphers(struct skcipher_alg *algs, int count);
void crypto_unregister_skciphers(struct skcipher_alg *algs, int count);
int skcipher_register_instance(struct crypto_template *tmpl,
struct skcipher_instance *inst);
int skcipher_walk_done(struct skcipher_walk *walk, int err);
int skcipher_walk_virt(struct skcipher_walk *walk,
struct skcipher_request *req,
bool atomic);
void skcipher_walk_atomise(struct skcipher_walk *walk);
int skcipher_walk_async(struct skcipher_walk *walk,
struct skcipher_request *req);
int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req,
bool atomic);
int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
struct aead_request *req, bool atomic);
int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
struct aead_request *req, bool atomic);
void skcipher_walk_complete(struct skcipher_walk *walk, int err);
static inline void ablkcipher_request_complete(struct ablkcipher_request *req,
int err)
{
req->base.complete(&req->base, err);
}
static inline u32 ablkcipher_request_flags(struct ablkcipher_request *req)
{
return req->base.flags;
}
static inline void *crypto_skcipher_ctx(struct crypto_skcipher *tfm)
{
return crypto_tfm_ctx(&tfm->base);
}
static inline void *skcipher_request_ctx(struct skcipher_request *req)
{
return req->__ctx;
}
static inline u32 skcipher_request_flags(struct skcipher_request *req)
{
return req->base.flags;
}
static inline unsigned int crypto_skcipher_alg_min_keysize(
struct skcipher_alg *alg)
{
if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
CRYPTO_ALG_TYPE_BLKCIPHER)
return alg->base.cra_blkcipher.min_keysize;
if (alg->base.cra_ablkcipher.encrypt)
return alg->base.cra_ablkcipher.min_keysize;
return alg->min_keysize;
}
static inline unsigned int crypto_skcipher_alg_max_keysize(
struct skcipher_alg *alg)
{
if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
CRYPTO_ALG_TYPE_BLKCIPHER)
return alg->base.cra_blkcipher.max_keysize;
if (alg->base.cra_ablkcipher.encrypt)
return alg->base.cra_ablkcipher.max_keysize;
return alg->max_keysize;
}
/* Helpers for simple block cipher modes of operation */
struct skcipher_ctx_simple {
struct crypto_cipher *cipher; /* underlying block cipher */
};
static inline struct crypto_cipher *
skcipher_cipher_simple(struct crypto_skcipher *tfm)
{
struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
return ctx->cipher;
}
struct skcipher_instance *
skcipher_alloc_instance_simple(struct crypto_template *tmpl, struct rtattr **tb,
struct crypto_alg **cipher_alg_ret);
#endif /* _CRYPTO_INTERNAL_SKCIPHER_H */