blob: d248008e7f7bc3f4225a87195e82e87191861336 [file] [log] [blame]
/*
* Symmetric key cipher operations.
*
* Generic encrypt/decrypt wrapper for ciphers, handles operations across
* multiple page boundaries by using temporary blocks. In user context,
* the kernel is given a chance to schedule us once per page.
*
* Copyright (c) 2015 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.
*
*/
#include <crypto/internal/skcipher.h>
#include <linux/bug.h>
#include <linux/cryptouser.h>
#include <linux/module.h>
#include <linux/rtnetlink.h>
#include <linux/seq_file.h>
#include <net/netlink.h>
#include "internal.h"
static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
{
if (alg->cra_type == &crypto_blkcipher_type)
return sizeof(struct crypto_blkcipher *);
if (alg->cra_type == &crypto_ablkcipher_type ||
alg->cra_type == &crypto_givcipher_type)
return sizeof(struct crypto_ablkcipher *);
return crypto_alg_extsize(alg);
}
static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
const u8 *key, unsigned int keylen)
{
struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
struct crypto_blkcipher *blkcipher = *ctx;
int err;
crypto_blkcipher_clear_flags(blkcipher, ~0);
crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
CRYPTO_TFM_REQ_MASK);
err = crypto_blkcipher_setkey(blkcipher, key, keylen);
crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
CRYPTO_TFM_RES_MASK);
return err;
}
static int skcipher_crypt_blkcipher(struct skcipher_request *req,
int (*crypt)(struct blkcipher_desc *,
struct scatterlist *,
struct scatterlist *,
unsigned int))
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
struct blkcipher_desc desc = {
.tfm = *ctx,
.info = req->iv,
.flags = req->base.flags,
};
return crypt(&desc, req->dst, req->src, req->cryptlen);
}
static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
{
struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
return skcipher_crypt_blkcipher(req, alg->encrypt);
}
static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
{
struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
return skcipher_crypt_blkcipher(req, alg->decrypt);
}
static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
{
struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
crypto_free_blkcipher(*ctx);
}
static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
{
struct crypto_alg *calg = tfm->__crt_alg;
struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
struct crypto_blkcipher *blkcipher;
struct crypto_tfm *btfm;
if (!crypto_mod_get(calg))
return -EAGAIN;
btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(btfm)) {
crypto_mod_put(calg);
return PTR_ERR(btfm);
}
blkcipher = __crypto_blkcipher_cast(btfm);
*ctx = blkcipher;
tfm->exit = crypto_exit_skcipher_ops_blkcipher;
skcipher->setkey = skcipher_setkey_blkcipher;
skcipher->encrypt = skcipher_encrypt_blkcipher;
skcipher->decrypt = skcipher_decrypt_blkcipher;
skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
skcipher->keysize = calg->cra_blkcipher.max_keysize;
return 0;
}
static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
const u8 *key, unsigned int keylen)
{
struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
struct crypto_ablkcipher *ablkcipher = *ctx;
int err;
crypto_ablkcipher_clear_flags(ablkcipher, ~0);
crypto_ablkcipher_set_flags(ablkcipher,
crypto_skcipher_get_flags(tfm) &
CRYPTO_TFM_REQ_MASK);
err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
crypto_skcipher_set_flags(tfm,
crypto_ablkcipher_get_flags(ablkcipher) &
CRYPTO_TFM_RES_MASK);
return err;
}
static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
int (*crypt)(struct ablkcipher_request *))
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
struct ablkcipher_request *subreq = skcipher_request_ctx(req);
ablkcipher_request_set_tfm(subreq, *ctx);
ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
req->base.complete, req->base.data);
ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
req->iv);
return crypt(subreq);
}
static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
{
struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
return skcipher_crypt_ablkcipher(req, alg->encrypt);
}
static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
{
struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
return skcipher_crypt_ablkcipher(req, alg->decrypt);
}
static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
{
struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
crypto_free_ablkcipher(*ctx);
}
static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
{
struct crypto_alg *calg = tfm->__crt_alg;
struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
struct crypto_ablkcipher *ablkcipher;
struct crypto_tfm *abtfm;
if (!crypto_mod_get(calg))
return -EAGAIN;
abtfm = __crypto_alloc_tfm(calg, 0, 0);
if (IS_ERR(abtfm)) {
crypto_mod_put(calg);
return PTR_ERR(abtfm);
}
ablkcipher = __crypto_ablkcipher_cast(abtfm);
*ctx = ablkcipher;
tfm->exit = crypto_exit_skcipher_ops_ablkcipher;
skcipher->setkey = skcipher_setkey_ablkcipher;
skcipher->encrypt = skcipher_encrypt_ablkcipher;
skcipher->decrypt = skcipher_decrypt_ablkcipher;
skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
sizeof(struct ablkcipher_request);
skcipher->keysize = calg->cra_ablkcipher.max_keysize;
return 0;
}
static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
alg->exit(skcipher);
}
static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
return crypto_init_skcipher_ops_blkcipher(tfm);
if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type ||
tfm->__crt_alg->cra_type == &crypto_givcipher_type)
return crypto_init_skcipher_ops_ablkcipher(tfm);
skcipher->setkey = alg->setkey;
skcipher->encrypt = alg->encrypt;
skcipher->decrypt = alg->decrypt;
skcipher->ivsize = alg->ivsize;
skcipher->keysize = alg->max_keysize;
if (alg->exit)
skcipher->base.exit = crypto_skcipher_exit_tfm;
if (alg->init)
return alg->init(skcipher);
return 0;
}
static void crypto_skcipher_free_instance(struct crypto_instance *inst)
{
struct skcipher_instance *skcipher =
container_of(inst, struct skcipher_instance, s.base);
skcipher->free(skcipher);
}
static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
__attribute__ ((unused));
static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
{
struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
base);
seq_printf(m, "type : skcipher\n");
seq_printf(m, "async : %s\n",
alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no");
seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
seq_printf(m, "min keysize : %u\n", skcipher->min_keysize);
seq_printf(m, "max keysize : %u\n", skcipher->max_keysize);
seq_printf(m, "ivsize : %u\n", skcipher->ivsize);
seq_printf(m, "chunksize : %u\n", skcipher->chunksize);
}
#ifdef CONFIG_NET
static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
struct crypto_report_blkcipher rblkcipher;
struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
base);
strncpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
strncpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
rblkcipher.blocksize = alg->cra_blocksize;
rblkcipher.min_keysize = skcipher->min_keysize;
rblkcipher.max_keysize = skcipher->max_keysize;
rblkcipher.ivsize = skcipher->ivsize;
if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
sizeof(struct crypto_report_blkcipher), &rblkcipher))
goto nla_put_failure;
return 0;
nla_put_failure:
return -EMSGSIZE;
}
#else
static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
{
return -ENOSYS;
}
#endif
static const struct crypto_type crypto_skcipher_type2 = {
.extsize = crypto_skcipher_extsize,
.init_tfm = crypto_skcipher_init_tfm,
.free = crypto_skcipher_free_instance,
#ifdef CONFIG_PROC_FS
.show = crypto_skcipher_show,
#endif
.report = crypto_skcipher_report,
.maskclear = ~CRYPTO_ALG_TYPE_MASK,
.maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
.type = CRYPTO_ALG_TYPE_SKCIPHER,
.tfmsize = offsetof(struct crypto_skcipher, base),
};
int crypto_grab_skcipher2(struct crypto_skcipher_spawn *spawn,
const char *name, u32 type, u32 mask)
{
spawn->base.frontend = &crypto_skcipher_type2;
return crypto_grab_spawn(&spawn->base, name, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_grab_skcipher2);
struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
u32 type, u32 mask)
{
return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask)
{
return crypto_type_has_alg(alg_name, &crypto_skcipher_type2,
type, mask);
}
EXPORT_SYMBOL_GPL(crypto_has_skcipher2);
static int skcipher_prepare_alg(struct skcipher_alg *alg)
{
struct crypto_alg *base = &alg->base;
if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8)
return -EINVAL;
if (!alg->chunksize)
alg->chunksize = base->cra_blocksize;
base->cra_type = &crypto_skcipher_type2;
base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
return 0;
}
int crypto_register_skcipher(struct skcipher_alg *alg)
{
struct crypto_alg *base = &alg->base;
int err;
err = skcipher_prepare_alg(alg);
if (err)
return err;
return crypto_register_alg(base);
}
EXPORT_SYMBOL_GPL(crypto_register_skcipher);
void crypto_unregister_skcipher(struct skcipher_alg *alg)
{
crypto_unregister_alg(&alg->base);
}
EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
int crypto_register_skciphers(struct skcipher_alg *algs, int count)
{
int i, ret;
for (i = 0; i < count; i++) {
ret = crypto_register_skcipher(&algs[i]);
if (ret)
goto err;
}
return 0;
err:
for (--i; i >= 0; --i)
crypto_unregister_skcipher(&algs[i]);
return ret;
}
EXPORT_SYMBOL_GPL(crypto_register_skciphers);
void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
{
int i;
for (i = count - 1; i >= 0; --i)
crypto_unregister_skcipher(&algs[i]);
}
EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
int skcipher_register_instance(struct crypto_template *tmpl,
struct skcipher_instance *inst)
{
int err;
err = skcipher_prepare_alg(&inst->alg);
if (err)
return err;
return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
}
EXPORT_SYMBOL_GPL(skcipher_register_instance);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Symmetric key cipher type");