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Diffstat (limited to 'kernel/fs/ext4/crypto.c')
-rw-r--r--kernel/fs/ext4/crypto.c261
1 files changed, 87 insertions, 174 deletions
diff --git a/kernel/fs/ext4/crypto.c b/kernel/fs/ext4/crypto.c
index 8ff15273a..1a0835073 100644
--- a/kernel/fs/ext4/crypto.c
+++ b/kernel/fs/ext4/crypto.c
@@ -55,6 +55,9 @@ static mempool_t *ext4_bounce_page_pool;
static LIST_HEAD(ext4_free_crypto_ctxs);
static DEFINE_SPINLOCK(ext4_crypto_ctx_lock);
+static struct kmem_cache *ext4_crypto_ctx_cachep;
+struct kmem_cache *ext4_crypt_info_cachep;
+
/**
* ext4_release_crypto_ctx() - Releases an encryption context
* @ctx: The encryption context to release.
@@ -68,18 +71,12 @@ void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx)
{
unsigned long flags;
- if (ctx->bounce_page) {
- if (ctx->flags & EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL)
- __free_page(ctx->bounce_page);
- else
- mempool_free(ctx->bounce_page, ext4_bounce_page_pool);
- ctx->bounce_page = NULL;
- }
- ctx->control_page = NULL;
+ if (ctx->flags & EXT4_WRITE_PATH_FL && ctx->w.bounce_page)
+ mempool_free(ctx->w.bounce_page, ext4_bounce_page_pool);
+ ctx->w.bounce_page = NULL;
+ ctx->w.control_page = NULL;
if (ctx->flags & EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL) {
- if (ctx->tfm)
- crypto_free_tfm(ctx->tfm);
- kfree(ctx);
+ kmem_cache_free(ext4_crypto_ctx_cachep, ctx);
} else {
spin_lock_irqsave(&ext4_crypto_ctx_lock, flags);
list_add(&ctx->free_list, &ext4_free_crypto_ctxs);
@@ -88,23 +85,6 @@ void ext4_release_crypto_ctx(struct ext4_crypto_ctx *ctx)
}
/**
- * ext4_alloc_and_init_crypto_ctx() - Allocates and inits an encryption context
- * @mask: The allocation mask.
- *
- * Return: An allocated and initialized encryption context on success. An error
- * value or NULL otherwise.
- */
-static struct ext4_crypto_ctx *ext4_alloc_and_init_crypto_ctx(gfp_t mask)
-{
- struct ext4_crypto_ctx *ctx = kzalloc(sizeof(struct ext4_crypto_ctx),
- mask);
-
- if (!ctx)
- return ERR_PTR(-ENOMEM);
- return ctx;
-}
-
-/**
* ext4_get_crypto_ctx() - Gets an encryption context
* @inode: The inode for which we are doing the crypto
*
@@ -118,10 +98,10 @@ struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode)
struct ext4_crypto_ctx *ctx = NULL;
int res = 0;
unsigned long flags;
- struct ext4_encryption_key *key = &EXT4_I(inode)->i_encryption_key;
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
- if (!ext4_read_workqueue)
- ext4_init_crypto();
+ if (ci == NULL)
+ return ERR_PTR(-ENOKEY);
/*
* We first try getting the ctx from a free list because in
@@ -140,50 +120,16 @@ struct ext4_crypto_ctx *ext4_get_crypto_ctx(struct inode *inode)
list_del(&ctx->free_list);
spin_unlock_irqrestore(&ext4_crypto_ctx_lock, flags);
if (!ctx) {
- ctx = ext4_alloc_and_init_crypto_ctx(GFP_NOFS);
- if (IS_ERR(ctx)) {
- res = PTR_ERR(ctx);
+ ctx = kmem_cache_zalloc(ext4_crypto_ctx_cachep, GFP_NOFS);
+ if (!ctx) {
+ res = -ENOMEM;
goto out;
}
ctx->flags |= EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL;
} else {
ctx->flags &= ~EXT4_CTX_REQUIRES_FREE_ENCRYPT_FL;
}
-
- /* Allocate a new Crypto API context if we don't already have
- * one or if it isn't the right mode. */
- BUG_ON(key->mode == EXT4_ENCRYPTION_MODE_INVALID);
- if (ctx->tfm && (ctx->mode != key->mode)) {
- crypto_free_tfm(ctx->tfm);
- ctx->tfm = NULL;
- ctx->mode = EXT4_ENCRYPTION_MODE_INVALID;
- }
- if (!ctx->tfm) {
- switch (key->mode) {
- case EXT4_ENCRYPTION_MODE_AES_256_XTS:
- ctx->tfm = crypto_ablkcipher_tfm(
- crypto_alloc_ablkcipher("xts(aes)", 0, 0));
- break;
- case EXT4_ENCRYPTION_MODE_AES_256_GCM:
- /* TODO(mhalcrow): AEAD w/ gcm(aes);
- * crypto_aead_setauthsize() */
- ctx->tfm = ERR_PTR(-ENOTSUPP);
- break;
- default:
- BUG();
- }
- if (IS_ERR_OR_NULL(ctx->tfm)) {
- res = PTR_ERR(ctx->tfm);
- ctx->tfm = NULL;
- goto out;
- }
- ctx->mode = key->mode;
- }
- BUG_ON(key->size != ext4_encryption_key_size(key->mode));
-
- /* There shouldn't be a bounce page attached to the crypto
- * context at this point. */
- BUG_ON(ctx->bounce_page);
+ ctx->flags &= ~EXT4_WRITE_PATH_FL;
out:
if (res) {
@@ -204,20 +150,8 @@ void ext4_exit_crypto(void)
{
struct ext4_crypto_ctx *pos, *n;
- list_for_each_entry_safe(pos, n, &ext4_free_crypto_ctxs, free_list) {
- if (pos->bounce_page) {
- if (pos->flags &
- EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL) {
- __free_page(pos->bounce_page);
- } else {
- mempool_free(pos->bounce_page,
- ext4_bounce_page_pool);
- }
- }
- if (pos->tfm)
- crypto_free_tfm(pos->tfm);
- kfree(pos);
- }
+ list_for_each_entry_safe(pos, n, &ext4_free_crypto_ctxs, free_list)
+ kmem_cache_free(ext4_crypto_ctx_cachep, pos);
INIT_LIST_HEAD(&ext4_free_crypto_ctxs);
if (ext4_bounce_page_pool)
mempool_destroy(ext4_bounce_page_pool);
@@ -225,6 +159,12 @@ void ext4_exit_crypto(void)
if (ext4_read_workqueue)
destroy_workqueue(ext4_read_workqueue);
ext4_read_workqueue = NULL;
+ if (ext4_crypto_ctx_cachep)
+ kmem_cache_destroy(ext4_crypto_ctx_cachep);
+ ext4_crypto_ctx_cachep = NULL;
+ if (ext4_crypt_info_cachep)
+ kmem_cache_destroy(ext4_crypt_info_cachep);
+ ext4_crypt_info_cachep = NULL;
}
/**
@@ -237,23 +177,31 @@ void ext4_exit_crypto(void)
*/
int ext4_init_crypto(void)
{
- int i, res;
+ int i, res = -ENOMEM;
mutex_lock(&crypto_init);
if (ext4_read_workqueue)
goto already_initialized;
ext4_read_workqueue = alloc_workqueue("ext4_crypto", WQ_HIGHPRI, 0);
- if (!ext4_read_workqueue) {
- res = -ENOMEM;
+ if (!ext4_read_workqueue)
+ goto fail;
+
+ ext4_crypto_ctx_cachep = KMEM_CACHE(ext4_crypto_ctx,
+ SLAB_RECLAIM_ACCOUNT);
+ if (!ext4_crypto_ctx_cachep)
+ goto fail;
+
+ ext4_crypt_info_cachep = KMEM_CACHE(ext4_crypt_info,
+ SLAB_RECLAIM_ACCOUNT);
+ if (!ext4_crypt_info_cachep)
goto fail;
- }
for (i = 0; i < num_prealloc_crypto_ctxs; i++) {
struct ext4_crypto_ctx *ctx;
- ctx = ext4_alloc_and_init_crypto_ctx(GFP_KERNEL);
- if (IS_ERR(ctx)) {
- res = PTR_ERR(ctx);
+ ctx = kmem_cache_zalloc(ext4_crypto_ctx_cachep, GFP_NOFS);
+ if (!ctx) {
+ res = -ENOMEM;
goto fail;
}
list_add(&ctx->free_list, &ext4_free_crypto_ctxs);
@@ -305,8 +253,7 @@ typedef enum {
EXT4_ENCRYPT,
} ext4_direction_t;
-static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,
- struct inode *inode,
+static int ext4_page_crypto(struct inode *inode,
ext4_direction_t rw,
pgoff_t index,
struct page *src_page,
@@ -317,32 +264,11 @@ static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,
struct ablkcipher_request *req = NULL;
DECLARE_EXT4_COMPLETION_RESULT(ecr);
struct scatterlist dst, src;
- struct ext4_inode_info *ei = EXT4_I(inode);
- struct crypto_ablkcipher *atfm = __crypto_ablkcipher_cast(ctx->tfm);
+ struct ext4_crypt_info *ci = EXT4_I(inode)->i_crypt_info;
+ struct crypto_ablkcipher *tfm = ci->ci_ctfm;
int res = 0;
- BUG_ON(!ctx->tfm);
- BUG_ON(ctx->mode != ei->i_encryption_key.mode);
-
- if (ctx->mode != EXT4_ENCRYPTION_MODE_AES_256_XTS) {
- printk_ratelimited(KERN_ERR
- "%s: unsupported crypto algorithm: %d\n",
- __func__, ctx->mode);
- return -ENOTSUPP;
- }
-
- crypto_ablkcipher_clear_flags(atfm, ~0);
- crypto_tfm_set_flags(ctx->tfm, CRYPTO_TFM_REQ_WEAK_KEY);
-
- res = crypto_ablkcipher_setkey(atfm, ei->i_encryption_key.raw,
- ei->i_encryption_key.size);
- if (res) {
- printk_ratelimited(KERN_ERR
- "%s: crypto_ablkcipher_setkey() failed\n",
- __func__);
- return res;
- }
- req = ablkcipher_request_alloc(atfm, GFP_NOFS);
+ req = ablkcipher_request_alloc(tfm, GFP_NOFS);
if (!req) {
printk_ratelimited(KERN_ERR
"%s: crypto_request_alloc() failed\n",
@@ -369,7 +295,6 @@ static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,
else
res = crypto_ablkcipher_encrypt(req);
if (res == -EINPROGRESS || res == -EBUSY) {
- BUG_ON(req->base.data != &ecr);
wait_for_completion(&ecr.completion);
res = ecr.res;
}
@@ -384,6 +309,15 @@ static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,
return 0;
}
+static struct page *alloc_bounce_page(struct ext4_crypto_ctx *ctx)
+{
+ ctx->w.bounce_page = mempool_alloc(ext4_bounce_page_pool, GFP_NOWAIT);
+ if (ctx->w.bounce_page == NULL)
+ return ERR_PTR(-ENOMEM);
+ ctx->flags |= EXT4_WRITE_PATH_FL;
+ return ctx->w.bounce_page;
+}
+
/**
* ext4_encrypt() - Encrypts a page
* @inode: The inode for which the encryption should take place
@@ -413,27 +347,17 @@ struct page *ext4_encrypt(struct inode *inode,
return (struct page *) ctx;
/* The encryption operation will require a bounce page. */
- ciphertext_page = alloc_page(GFP_NOFS);
- if (!ciphertext_page) {
- /* This is a potential bottleneck, but at least we'll have
- * forward progress. */
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS);
- if (WARN_ON_ONCE(!ciphertext_page)) {
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS | __GFP_WAIT);
- }
- ctx->flags &= ~EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
- } else {
- ctx->flags |= EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
- }
- ctx->bounce_page = ciphertext_page;
- ctx->control_page = plaintext_page;
- err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, plaintext_page->index,
+ ciphertext_page = alloc_bounce_page(ctx);
+ if (IS_ERR(ciphertext_page))
+ goto errout;
+ ctx->w.control_page = plaintext_page;
+ err = ext4_page_crypto(inode, EXT4_ENCRYPT, plaintext_page->index,
plaintext_page, ciphertext_page);
if (err) {
+ ciphertext_page = ERR_PTR(err);
+ errout:
ext4_release_crypto_ctx(ctx);
- return ERR_PTR(err);
+ return ciphertext_page;
}
SetPagePrivate(ciphertext_page);
set_page_private(ciphertext_page, (unsigned long)ctx);
@@ -452,40 +376,29 @@ struct page *ext4_encrypt(struct inode *inode,
*
* Return: Zero on success, non-zero otherwise.
*/
-int ext4_decrypt(struct ext4_crypto_ctx *ctx, struct page *page)
+int ext4_decrypt(struct page *page)
{
BUG_ON(!PageLocked(page));
- return ext4_page_crypto(ctx, page->mapping->host,
+ return ext4_page_crypto(page->mapping->host,
EXT4_DECRYPT, page->index, page, page);
}
-/*
- * Convenience function which takes care of allocating and
- * deallocating the encryption context
- */
-int ext4_decrypt_one(struct inode *inode, struct page *page)
-{
- int ret;
-
- struct ext4_crypto_ctx *ctx = ext4_get_crypto_ctx(inode);
-
- if (!ctx)
- return -ENOMEM;
- ret = ext4_decrypt(ctx, page);
- ext4_release_crypto_ctx(ctx);
- return ret;
-}
-
int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)
{
struct ext4_crypto_ctx *ctx;
struct page *ciphertext_page = NULL;
struct bio *bio;
- ext4_lblk_t lblk = ex->ee_block;
+ ext4_lblk_t lblk = le32_to_cpu(ex->ee_block);
ext4_fsblk_t pblk = ext4_ext_pblock(ex);
unsigned int len = ext4_ext_get_actual_len(ex);
- int err = 0;
+ int ret, err = 0;
+
+#if 0
+ ext4_msg(inode->i_sb, KERN_CRIT,
+ "ext4_encrypted_zeroout ino %lu lblk %u len %u",
+ (unsigned long) inode->i_ino, lblk, len);
+#endif
BUG_ON(inode->i_sb->s_blocksize != PAGE_CACHE_SIZE);
@@ -493,24 +406,14 @@ int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)
if (IS_ERR(ctx))
return PTR_ERR(ctx);
- ciphertext_page = alloc_page(GFP_NOFS);
- if (!ciphertext_page) {
- /* This is a potential bottleneck, but at least we'll have
- * forward progress. */
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS);
- if (WARN_ON_ONCE(!ciphertext_page)) {
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS | __GFP_WAIT);
- }
- ctx->flags &= ~EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
- } else {
- ctx->flags |= EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
+ ciphertext_page = alloc_bounce_page(ctx);
+ if (IS_ERR(ciphertext_page)) {
+ err = PTR_ERR(ciphertext_page);
+ goto errout;
}
- ctx->bounce_page = ciphertext_page;
while (len--) {
- err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, lblk,
+ err = ext4_page_crypto(inode, EXT4_ENCRYPT, lblk,
ZERO_PAGE(0), ciphertext_page);
if (err)
goto errout;
@@ -521,16 +424,26 @@ int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)
goto errout;
}
bio->bi_bdev = inode->i_sb->s_bdev;
- bio->bi_iter.bi_sector = pblk;
- err = bio_add_page(bio, ciphertext_page,
+ bio->bi_iter.bi_sector =
+ pblk << (inode->i_sb->s_blocksize_bits - 9);
+ ret = bio_add_page(bio, ciphertext_page,
inode->i_sb->s_blocksize, 0);
- if (err) {
+ if (ret != inode->i_sb->s_blocksize) {
+ /* should never happen! */
+ ext4_msg(inode->i_sb, KERN_ERR,
+ "bio_add_page failed: %d", ret);
+ WARN_ON(1);
bio_put(bio);
+ err = -EIO;
goto errout;
}
err = submit_bio_wait(WRITE, bio);
+ if ((err == 0) && bio->bi_error)
+ err = -EIO;
+ bio_put(bio);
if (err)
goto errout;
+ lblk++; pblk++;
}
err = 0;
errout: