Revision 5ccf92037c7c6e6f28175fd245284923f939259f authored by Tyler Hicks on 24 May 2011, 07:16:51 UTC, committed by Tyler Hicks on 29 May 2011, 17:51:17 UTC
The eCryptfs inode get, initialization, and dentry interposition code has two separate paths. One is for when dentry interposition is needed after doing things like a mkdir in the lower filesystem and the other is needed after a lookup. Unlocking new inodes and doing a d_add() needs to happen at different times, depending on which type of dentry interposing is being done. This patch cleans up the inode get and initialization code paths and splits them up so that the locking and d_add() differences mentioned above can be handled appropriately in a later patch. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Tested-by: David <david@unsolicited.net>
1 parent c4f7907
ctr.c
/*
* CTR: Counter mode
*
* (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
*
* 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/algapi.h>
#include <crypto/ctr.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
struct crypto_ctr_ctx {
struct crypto_cipher *child;
};
struct crypto_rfc3686_ctx {
struct crypto_blkcipher *child;
u8 nonce[CTR_RFC3686_NONCE_SIZE];
};
static int crypto_ctr_setkey(struct crypto_tfm *parent, const u8 *key,
unsigned int keylen)
{
struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(parent);
struct crypto_cipher *child = ctx->child;
int err;
crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) &
CRYPTO_TFM_REQ_MASK);
err = crypto_cipher_setkey(child, key, keylen);
crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) &
CRYPTO_TFM_RES_MASK);
return err;
}
static void crypto_ctr_crypt_final(struct blkcipher_walk *walk,
struct crypto_cipher *tfm)
{
unsigned int bsize = crypto_cipher_blocksize(tfm);
unsigned long alignmask = crypto_cipher_alignmask(tfm);
u8 *ctrblk = walk->iv;
u8 tmp[bsize + alignmask];
u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1);
u8 *src = walk->src.virt.addr;
u8 *dst = walk->dst.virt.addr;
unsigned int nbytes = walk->nbytes;
crypto_cipher_encrypt_one(tfm, keystream, ctrblk);
crypto_xor(keystream, src, nbytes);
memcpy(dst, keystream, nbytes);
crypto_inc(ctrblk, bsize);
}
static int crypto_ctr_crypt_segment(struct blkcipher_walk *walk,
struct crypto_cipher *tfm)
{
void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
crypto_cipher_alg(tfm)->cia_encrypt;
unsigned int bsize = crypto_cipher_blocksize(tfm);
u8 *ctrblk = walk->iv;
u8 *src = walk->src.virt.addr;
u8 *dst = walk->dst.virt.addr;
unsigned int nbytes = walk->nbytes;
do {
/* create keystream */
fn(crypto_cipher_tfm(tfm), dst, ctrblk);
crypto_xor(dst, src, bsize);
/* increment counter in counterblock */
crypto_inc(ctrblk, bsize);
src += bsize;
dst += bsize;
} while ((nbytes -= bsize) >= bsize);
return nbytes;
}
static int crypto_ctr_crypt_inplace(struct blkcipher_walk *walk,
struct crypto_cipher *tfm)
{
void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
crypto_cipher_alg(tfm)->cia_encrypt;
unsigned int bsize = crypto_cipher_blocksize(tfm);
unsigned long alignmask = crypto_cipher_alignmask(tfm);
unsigned int nbytes = walk->nbytes;
u8 *ctrblk = walk->iv;
u8 *src = walk->src.virt.addr;
u8 tmp[bsize + alignmask];
u8 *keystream = PTR_ALIGN(tmp + 0, alignmask + 1);
do {
/* create keystream */
fn(crypto_cipher_tfm(tfm), keystream, ctrblk);
crypto_xor(src, keystream, bsize);
/* increment counter in counterblock */
crypto_inc(ctrblk, bsize);
src += bsize;
} while ((nbytes -= bsize) >= bsize);
return nbytes;
}
static int crypto_ctr_crypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct blkcipher_walk walk;
struct crypto_blkcipher *tfm = desc->tfm;
struct crypto_ctr_ctx *ctx = crypto_blkcipher_ctx(tfm);
struct crypto_cipher *child = ctx->child;
unsigned int bsize = crypto_cipher_blocksize(child);
int err;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt_block(desc, &walk, bsize);
while (walk.nbytes >= bsize) {
if (walk.src.virt.addr == walk.dst.virt.addr)
nbytes = crypto_ctr_crypt_inplace(&walk, child);
else
nbytes = crypto_ctr_crypt_segment(&walk, child);
err = blkcipher_walk_done(desc, &walk, nbytes);
}
if (walk.nbytes) {
crypto_ctr_crypt_final(&walk, child);
err = blkcipher_walk_done(desc, &walk, 0);
}
return err;
}
static int crypto_ctr_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_instance *inst = (void *)tfm->__crt_alg;
struct crypto_spawn *spawn = crypto_instance_ctx(inst);
struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(tfm);
struct crypto_cipher *cipher;
cipher = crypto_spawn_cipher(spawn);
if (IS_ERR(cipher))
return PTR_ERR(cipher);
ctx->child = cipher;
return 0;
}
static void crypto_ctr_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_ctr_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_cipher(ctx->child);
}
static struct crypto_instance *crypto_ctr_alloc(struct rtattr **tb)
{
struct crypto_instance *inst;
struct crypto_alg *alg;
int err;
err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER);
if (err)
return ERR_PTR(err);
alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(alg))
return ERR_CAST(alg);
/* Block size must be >= 4 bytes. */
err = -EINVAL;
if (alg->cra_blocksize < 4)
goto out_put_alg;
/* If this is false we'd fail the alignment of crypto_inc. */
if (alg->cra_blocksize % 4)
goto out_put_alg;
inst = crypto_alloc_instance("ctr", alg);
if (IS_ERR(inst))
goto out;
inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
inst->alg.cra_priority = alg->cra_priority;
inst->alg.cra_blocksize = 1;
inst->alg.cra_alignmask = alg->cra_alignmask | (__alignof__(u32) - 1);
inst->alg.cra_type = &crypto_blkcipher_type;
inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize;
inst->alg.cra_blkcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
inst->alg.cra_blkcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
inst->alg.cra_ctxsize = sizeof(struct crypto_ctr_ctx);
inst->alg.cra_init = crypto_ctr_init_tfm;
inst->alg.cra_exit = crypto_ctr_exit_tfm;
inst->alg.cra_blkcipher.setkey = crypto_ctr_setkey;
inst->alg.cra_blkcipher.encrypt = crypto_ctr_crypt;
inst->alg.cra_blkcipher.decrypt = crypto_ctr_crypt;
inst->alg.cra_blkcipher.geniv = "chainiv";
out:
crypto_mod_put(alg);
return inst;
out_put_alg:
inst = ERR_PTR(err);
goto out;
}
static void crypto_ctr_free(struct crypto_instance *inst)
{
crypto_drop_spawn(crypto_instance_ctx(inst));
kfree(inst);
}
static struct crypto_template crypto_ctr_tmpl = {
.name = "ctr",
.alloc = crypto_ctr_alloc,
.free = crypto_ctr_free,
.module = THIS_MODULE,
};
static int crypto_rfc3686_setkey(struct crypto_tfm *parent, const u8 *key,
unsigned int keylen)
{
struct crypto_rfc3686_ctx *ctx = crypto_tfm_ctx(parent);
struct crypto_blkcipher *child = ctx->child;
int err;
/* the nonce is stored in bytes at end of key */
if (keylen < CTR_RFC3686_NONCE_SIZE)
return -EINVAL;
memcpy(ctx->nonce, key + (keylen - CTR_RFC3686_NONCE_SIZE),
CTR_RFC3686_NONCE_SIZE);
keylen -= CTR_RFC3686_NONCE_SIZE;
crypto_blkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK);
crypto_blkcipher_set_flags(child, crypto_tfm_get_flags(parent) &
CRYPTO_TFM_REQ_MASK);
err = crypto_blkcipher_setkey(child, key, keylen);
crypto_tfm_set_flags(parent, crypto_blkcipher_get_flags(child) &
CRYPTO_TFM_RES_MASK);
return err;
}
static int crypto_rfc3686_crypt(struct blkcipher_desc *desc,
struct scatterlist *dst,
struct scatterlist *src, unsigned int nbytes)
{
struct crypto_blkcipher *tfm = desc->tfm;
struct crypto_rfc3686_ctx *ctx = crypto_blkcipher_ctx(tfm);
struct crypto_blkcipher *child = ctx->child;
unsigned long alignmask = crypto_blkcipher_alignmask(tfm);
u8 ivblk[CTR_RFC3686_BLOCK_SIZE + alignmask];
u8 *iv = PTR_ALIGN(ivblk + 0, alignmask + 1);
u8 *info = desc->info;
int err;
/* set up counter block */
memcpy(iv, ctx->nonce, CTR_RFC3686_NONCE_SIZE);
memcpy(iv + CTR_RFC3686_NONCE_SIZE, info, CTR_RFC3686_IV_SIZE);
/* initialize counter portion of counter block */
*(__be32 *)(iv + CTR_RFC3686_NONCE_SIZE + CTR_RFC3686_IV_SIZE) =
cpu_to_be32(1);
desc->tfm = child;
desc->info = iv;
err = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes);
desc->tfm = tfm;
desc->info = info;
return err;
}
static int crypto_rfc3686_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_instance *inst = (void *)tfm->__crt_alg;
struct crypto_spawn *spawn = crypto_instance_ctx(inst);
struct crypto_rfc3686_ctx *ctx = crypto_tfm_ctx(tfm);
struct crypto_blkcipher *cipher;
cipher = crypto_spawn_blkcipher(spawn);
if (IS_ERR(cipher))
return PTR_ERR(cipher);
ctx->child = cipher;
return 0;
}
static void crypto_rfc3686_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_rfc3686_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_blkcipher(ctx->child);
}
static struct crypto_instance *crypto_rfc3686_alloc(struct rtattr **tb)
{
struct crypto_instance *inst;
struct crypto_alg *alg;
int err;
err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER);
if (err)
return ERR_PTR(err);
alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_BLKCIPHER,
CRYPTO_ALG_TYPE_MASK);
err = PTR_ERR(alg);
if (IS_ERR(alg))
return ERR_PTR(err);
/* We only support 16-byte blocks. */
err = -EINVAL;
if (alg->cra_blkcipher.ivsize != CTR_RFC3686_BLOCK_SIZE)
goto out_put_alg;
/* Not a stream cipher? */
if (alg->cra_blocksize != 1)
goto out_put_alg;
inst = crypto_alloc_instance("rfc3686", alg);
if (IS_ERR(inst))
goto out;
inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER;
inst->alg.cra_priority = alg->cra_priority;
inst->alg.cra_blocksize = 1;
inst->alg.cra_alignmask = alg->cra_alignmask;
inst->alg.cra_type = &crypto_blkcipher_type;
inst->alg.cra_blkcipher.ivsize = CTR_RFC3686_IV_SIZE;
inst->alg.cra_blkcipher.min_keysize = alg->cra_blkcipher.min_keysize
+ CTR_RFC3686_NONCE_SIZE;
inst->alg.cra_blkcipher.max_keysize = alg->cra_blkcipher.max_keysize
+ CTR_RFC3686_NONCE_SIZE;
inst->alg.cra_blkcipher.geniv = "seqiv";
inst->alg.cra_ctxsize = sizeof(struct crypto_rfc3686_ctx);
inst->alg.cra_init = crypto_rfc3686_init_tfm;
inst->alg.cra_exit = crypto_rfc3686_exit_tfm;
inst->alg.cra_blkcipher.setkey = crypto_rfc3686_setkey;
inst->alg.cra_blkcipher.encrypt = crypto_rfc3686_crypt;
inst->alg.cra_blkcipher.decrypt = crypto_rfc3686_crypt;
out:
crypto_mod_put(alg);
return inst;
out_put_alg:
inst = ERR_PTR(err);
goto out;
}
static struct crypto_template crypto_rfc3686_tmpl = {
.name = "rfc3686",
.alloc = crypto_rfc3686_alloc,
.free = crypto_ctr_free,
.module = THIS_MODULE,
};
static int __init crypto_ctr_module_init(void)
{
int err;
err = crypto_register_template(&crypto_ctr_tmpl);
if (err)
goto out;
err = crypto_register_template(&crypto_rfc3686_tmpl);
if (err)
goto out_drop_ctr;
out:
return err;
out_drop_ctr:
crypto_unregister_template(&crypto_ctr_tmpl);
goto out;
}
static void __exit crypto_ctr_module_exit(void)
{
crypto_unregister_template(&crypto_rfc3686_tmpl);
crypto_unregister_template(&crypto_ctr_tmpl);
}
module_init(crypto_ctr_module_init);
module_exit(crypto_ctr_module_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("CTR Counter block mode");
MODULE_ALIAS("rfc3686");
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