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-rw-r--r--fs/crypto/Kconfig1
-rw-r--r--fs/crypto/Makefile1
-rw-r--r--fs/crypto/bio.c145
-rw-r--r--fs/crypto/crypto.c167
-rw-r--r--fs/crypto/fname.c6
-rw-r--r--fs/crypto/fscrypt_private.h24
-rw-r--r--fs/crypto/keyinfo.c99
-rw-r--r--fs/crypto/policy.c102
8 files changed, 243 insertions, 302 deletions
diff --git a/fs/crypto/Kconfig b/fs/crypto/Kconfig
index f514978f6688..08b46e6e3995 100644
--- a/fs/crypto/Kconfig
+++ b/fs/crypto/Kconfig
@@ -1,6 +1,5 @@
config FS_ENCRYPTION
tristate "FS Encryption (Per-file encryption)"
- depends on BLOCK
select CRYPTO
select CRYPTO_AES
select CRYPTO_CBC
diff --git a/fs/crypto/Makefile b/fs/crypto/Makefile
index f17684c48739..9f6607f17b53 100644
--- a/fs/crypto/Makefile
+++ b/fs/crypto/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_FS_ENCRYPTION) += fscrypto.o
fscrypto-y := crypto.o fname.o policy.o keyinfo.o
+fscrypto-$(CONFIG_BLOCK) += bio.o
diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
new file mode 100644
index 000000000000..a409a84f1bca
--- /dev/null
+++ b/fs/crypto/bio.c
@@ -0,0 +1,145 @@
+/*
+ * This contains encryption functions for per-file encryption.
+ *
+ * Copyright (C) 2015, Google, Inc.
+ * Copyright (C) 2015, Motorola Mobility
+ *
+ * Written by Michael Halcrow, 2014.
+ *
+ * Filename encryption additions
+ * Uday Savagaonkar, 2014
+ * Encryption policy handling additions
+ * Ildar Muslukhov, 2014
+ * Add fscrypt_pullback_bio_page()
+ * Jaegeuk Kim, 2015.
+ *
+ * This has not yet undergone a rigorous security audit.
+ *
+ * The usage of AES-XTS should conform to recommendations in NIST
+ * Special Publication 800-38E and IEEE P1619/D16.
+ */
+
+#include <linux/pagemap.h>
+#include <linux/module.h>
+#include <linux/bio.h>
+#include <linux/namei.h>
+#include "fscrypt_private.h"
+
+/*
+ * Call fscrypt_decrypt_page on every single page, reusing the encryption
+ * context.
+ */
+static void completion_pages(struct work_struct *work)
+{
+ struct fscrypt_ctx *ctx =
+ container_of(work, struct fscrypt_ctx, r.work);
+ struct bio *bio = ctx->r.bio;
+ struct bio_vec *bv;
+ int i;
+
+ bio_for_each_segment_all(bv, bio, i) {
+ struct page *page = bv->bv_page;
+ int ret = fscrypt_decrypt_page(page->mapping->host, page,
+ PAGE_SIZE, 0, page->index);
+
+ if (ret) {
+ WARN_ON_ONCE(1);
+ SetPageError(page);
+ } else {
+ SetPageUptodate(page);
+ }
+ unlock_page(page);
+ }
+ fscrypt_release_ctx(ctx);
+ bio_put(bio);
+}
+
+void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *ctx, struct bio *bio)
+{
+ INIT_WORK(&ctx->r.work, completion_pages);
+ ctx->r.bio = bio;
+ queue_work(fscrypt_read_workqueue, &ctx->r.work);
+}
+EXPORT_SYMBOL(fscrypt_decrypt_bio_pages);
+
+void fscrypt_pullback_bio_page(struct page **page, bool restore)
+{
+ struct fscrypt_ctx *ctx;
+ struct page *bounce_page;
+
+ /* The bounce data pages are unmapped. */
+ if ((*page)->mapping)
+ return;
+
+ /* The bounce data page is unmapped. */
+ bounce_page = *page;
+ ctx = (struct fscrypt_ctx *)page_private(bounce_page);
+
+ /* restore control page */
+ *page = ctx->w.control_page;
+
+ if (restore)
+ fscrypt_restore_control_page(bounce_page);
+}
+EXPORT_SYMBOL(fscrypt_pullback_bio_page);
+
+int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
+ sector_t pblk, unsigned int len)
+{
+ struct fscrypt_ctx *ctx;
+ struct page *ciphertext_page = NULL;
+ struct bio *bio;
+ int ret, err = 0;
+
+ BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
+
+ ctx = fscrypt_get_ctx(inode, GFP_NOFS);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+
+ ciphertext_page = fscrypt_alloc_bounce_page(ctx, GFP_NOWAIT);
+ if (IS_ERR(ciphertext_page)) {
+ err = PTR_ERR(ciphertext_page);
+ goto errout;
+ }
+
+ while (len--) {
+ err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk,
+ ZERO_PAGE(0), ciphertext_page,
+ PAGE_SIZE, 0, GFP_NOFS);
+ if (err)
+ goto errout;
+
+ bio = bio_alloc(GFP_NOWAIT, 1);
+ if (!bio) {
+ err = -ENOMEM;
+ goto errout;
+ }
+ bio->bi_bdev = inode->i_sb->s_bdev;
+ bio->bi_iter.bi_sector =
+ pblk << (inode->i_sb->s_blocksize_bits - 9);
+ bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
+ ret = bio_add_page(bio, ciphertext_page,
+ inode->i_sb->s_blocksize, 0);
+ if (ret != inode->i_sb->s_blocksize) {
+ /* should never happen! */
+ WARN_ON(1);
+ bio_put(bio);
+ err = -EIO;
+ goto errout;
+ }
+ err = submit_bio_wait(bio);
+ if ((err == 0) && bio->bi_error)
+ err = -EIO;
+ bio_put(bio);
+ if (err)
+ goto errout;
+ lblk++;
+ pblk++;
+ }
+ err = 0;
+errout:
+ fscrypt_release_ctx(ctx);
+ return err;
+}
+EXPORT_SYMBOL(fscrypt_zeroout_range);
diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index ac8e4f6a3773..6d6eca394d4d 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -24,7 +24,6 @@
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/ratelimit.h>
-#include <linux/bio.h>
#include <linux/dcache.h>
#include <linux/namei.h>
#include "fscrypt_private.h"
@@ -44,7 +43,7 @@ static mempool_t *fscrypt_bounce_page_pool = NULL;
static LIST_HEAD(fscrypt_free_ctxs);
static DEFINE_SPINLOCK(fscrypt_ctx_lock);
-static struct workqueue_struct *fscrypt_read_workqueue;
+struct workqueue_struct *fscrypt_read_workqueue;
static DEFINE_MUTEX(fscrypt_init_mutex);
static struct kmem_cache *fscrypt_ctx_cachep;
@@ -141,16 +140,10 @@ static void page_crypt_complete(struct crypto_async_request *req, int res)
complete(&ecr->completion);
}
-typedef enum {
- FS_DECRYPT = 0,
- FS_ENCRYPT,
-} fscrypt_direction_t;
-
-static int do_page_crypto(const struct inode *inode,
- fscrypt_direction_t rw, u64 lblk_num,
- struct page *src_page, struct page *dest_page,
- unsigned int len, unsigned int offs,
- gfp_t gfp_flags)
+int fscrypt_do_page_crypto(const struct inode *inode, fscrypt_direction_t rw,
+ u64 lblk_num, struct page *src_page,
+ struct page *dest_page, unsigned int len,
+ unsigned int offs, gfp_t gfp_flags)
{
struct {
__le64 index;
@@ -205,7 +198,8 @@ static int do_page_crypto(const struct inode *inode,
return 0;
}
-static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx, gfp_t gfp_flags)
+struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
+ gfp_t gfp_flags)
{
ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool, gfp_flags);
if (ctx->w.bounce_page == NULL)
@@ -260,9 +254,9 @@ struct page *fscrypt_encrypt_page(const struct inode *inode,
if (inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES) {
/* with inplace-encryption we just encrypt the page */
- err = do_page_crypto(inode, FS_ENCRYPT, lblk_num,
- page, ciphertext_page,
- len, offs, gfp_flags);
+ err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num, page,
+ ciphertext_page, len, offs,
+ gfp_flags);
if (err)
return ERR_PTR(err);
@@ -276,14 +270,14 @@ struct page *fscrypt_encrypt_page(const struct inode *inode,
return (struct page *)ctx;
/* The encryption operation will require a bounce page. */
- ciphertext_page = alloc_bounce_page(ctx, gfp_flags);
+ ciphertext_page = fscrypt_alloc_bounce_page(ctx, gfp_flags);
if (IS_ERR(ciphertext_page))
goto errout;
ctx->w.control_page = page;
- err = do_page_crypto(inode, FS_ENCRYPT, lblk_num,
- page, ciphertext_page,
- len, offs, gfp_flags);
+ err = fscrypt_do_page_crypto(inode, FS_ENCRYPT, lblk_num,
+ page, ciphertext_page, len, offs,
+ gfp_flags);
if (err) {
ciphertext_page = ERR_PTR(err);
goto errout;
@@ -320,72 +314,11 @@ int fscrypt_decrypt_page(const struct inode *inode, struct page *page,
if (!(inode->i_sb->s_cop->flags & FS_CFLG_OWN_PAGES))
BUG_ON(!PageLocked(page));
- return do_page_crypto(inode, FS_DECRYPT, lblk_num, page, page, len,
- offs, GFP_NOFS);
+ return fscrypt_do_page_crypto(inode, FS_DECRYPT, lblk_num, page, page,
+ len, offs, GFP_NOFS);
}
EXPORT_SYMBOL(fscrypt_decrypt_page);
-int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
- sector_t pblk, unsigned int len)
-{
- struct fscrypt_ctx *ctx;
- struct page *ciphertext_page = NULL;
- struct bio *bio;
- int ret, err = 0;
-
- BUG_ON(inode->i_sb->s_blocksize != PAGE_SIZE);
-
- ctx = fscrypt_get_ctx(inode, GFP_NOFS);
- if (IS_ERR(ctx))
- return PTR_ERR(ctx);
-
- ciphertext_page = alloc_bounce_page(ctx, GFP_NOWAIT);
- if (IS_ERR(ciphertext_page)) {
- err = PTR_ERR(ciphertext_page);
- goto errout;
- }
-
- while (len--) {
- err = do_page_crypto(inode, FS_ENCRYPT, lblk,
- ZERO_PAGE(0), ciphertext_page,
- PAGE_SIZE, 0, GFP_NOFS);
- if (err)
- goto errout;
-
- bio = bio_alloc(GFP_NOWAIT, 1);
- if (!bio) {
- err = -ENOMEM;
- goto errout;
- }
- bio->bi_bdev = inode->i_sb->s_bdev;
- bio->bi_iter.bi_sector =
- pblk << (inode->i_sb->s_blocksize_bits - 9);
- bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
- ret = bio_add_page(bio, ciphertext_page,
- inode->i_sb->s_blocksize, 0);
- if (ret != inode->i_sb->s_blocksize) {
- /* should never happen! */
- WARN_ON(1);
- bio_put(bio);
- err = -EIO;
- goto errout;
- }
- err = submit_bio_wait(bio);
- if ((err == 0) && bio->bi_error)
- err = -EIO;
- bio_put(bio);
- if (err)
- goto errout;
- lblk++;
- pblk++;
- }
- err = 0;
-errout:
- fscrypt_release_ctx(ctx);
- return err;
-}
-EXPORT_SYMBOL(fscrypt_zeroout_range);
-
/*
* Validate dentries for encrypted directories to make sure we aren't
* potentially caching stale data after a key has been added or
@@ -394,7 +327,6 @@ EXPORT_SYMBOL(fscrypt_zeroout_range);
static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
{
struct dentry *dir;
- struct fscrypt_info *ci;
int dir_has_key, cached_with_key;
if (flags & LOOKUP_RCU)
@@ -406,18 +338,11 @@ static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
return 0;
}
- ci = d_inode(dir)->i_crypt_info;
- if (ci && ci->ci_keyring_key &&
- (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
- (1 << KEY_FLAG_REVOKED) |
- (1 << KEY_FLAG_DEAD))))
- ci = NULL;
-
/* this should eventually be an flag in d_flags */
spin_lock(&dentry->d_lock);
cached_with_key = dentry->d_flags & DCACHE_ENCRYPTED_WITH_KEY;
spin_unlock(&dentry->d_lock);
- dir_has_key = (ci != NULL);
+ dir_has_key = (d_inode(dir)->i_crypt_info != NULL);
dput(dir);
/*
@@ -442,64 +367,6 @@ const struct dentry_operations fscrypt_d_ops = {
};
EXPORT_SYMBOL(fscrypt_d_ops);
-/*
- * Call fscrypt_decrypt_page on every single page, reusing the encryption
- * context.
- */
-static void completion_pages(struct work_struct *work)
-{
- struct fscrypt_ctx *ctx =
- container_of(work, struct fscrypt_ctx, r.work);
- struct bio *bio = ctx->r.bio;
- struct bio_vec *bv;
- int i;
-
- bio_for_each_segment_all(bv, bio, i) {
- struct page *page = bv->bv_page;
- int ret = fscrypt_decrypt_page(page->mapping->host, page,
- PAGE_SIZE, 0, page->index);
-
- if (ret) {
- WARN_ON_ONCE(1);
- SetPageError(page);
- } else {
- SetPageUptodate(page);
- }
- unlock_page(page);
- }
- fscrypt_release_ctx(ctx);
- bio_put(bio);
-}
-
-void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *ctx, struct bio *bio)
-{
- INIT_WORK(&ctx->r.work, completion_pages);
- ctx->r.bio = bio;
- queue_work(fscrypt_read_workqueue, &ctx->r.work);
-}
-EXPORT_SYMBOL(fscrypt_decrypt_bio_pages);
-
-void fscrypt_pullback_bio_page(struct page **page, bool restore)
-{
- struct fscrypt_ctx *ctx;
- struct page *bounce_page;
-
- /* The bounce data pages are unmapped. */
- if ((*page)->mapping)
- return;
-
- /* The bounce data page is unmapped. */
- bounce_page = *page;
- ctx = (struct fscrypt_ctx *)page_private(bounce_page);
-
- /* restore control page */
- *page = ctx->w.control_page;
-
- if (restore)
- fscrypt_restore_control_page(bounce_page);
-}
-EXPORT_SYMBOL(fscrypt_pullback_bio_page);
-
void fscrypt_restore_control_page(struct page *page)
{
struct fscrypt_ctx *ctx;
diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 56ad9d195f18..37b49894c762 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -332,7 +332,7 @@ int fscrypt_fname_usr_to_disk(struct inode *inode,
* in a directory. Consequently, a user space name cannot be mapped to
* a disk-space name
*/
- return -EACCES;
+ return -ENOKEY;
}
EXPORT_SYMBOL(fscrypt_fname_usr_to_disk);
@@ -350,7 +350,7 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
fname->disk_name.len = iname->len;
return 0;
}
- ret = fscrypt_get_crypt_info(dir);
+ ret = fscrypt_get_encryption_info(dir);
if (ret && ret != -EOPNOTSUPP)
return ret;
@@ -367,7 +367,7 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
return 0;
}
if (!lookup)
- return -EACCES;
+ return -ENOKEY;
/*
* We don't have the key and we are doing a lookup; decode the
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index aeab032d7d35..e39696e64494 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -11,7 +11,7 @@
#ifndef _FSCRYPT_PRIVATE_H
#define _FSCRYPT_PRIVATE_H
-#include <linux/fscrypto.h>
+#include <linux/fscrypt_supp.h>
#define FS_FNAME_CRYPTO_DIGEST_SIZE 32
@@ -67,10 +67,14 @@ struct fscrypt_info {
u8 ci_filename_mode;
u8 ci_flags;
struct crypto_skcipher *ci_ctfm;
- struct key *ci_keyring_key;
u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
};
+typedef enum {
+ FS_DECRYPT = 0,
+ FS_ENCRYPT,
+} fscrypt_direction_t;
+
#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
#define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002
@@ -81,13 +85,19 @@ struct fscrypt_completion_result {
#define DECLARE_FS_COMPLETION_RESULT(ecr) \
struct fscrypt_completion_result ecr = { \
- COMPLETION_INITIALIZER((ecr).completion), 0 }
+ COMPLETION_INITIALIZER_ONSTACK((ecr).completion), 0 }
/* crypto.c */
-int fscrypt_initialize(unsigned int cop_flags);
-
-/* keyinfo.c */
-extern int fscrypt_get_crypt_info(struct inode *);
+extern int fscrypt_initialize(unsigned int cop_flags);
+extern struct workqueue_struct *fscrypt_read_workqueue;
+extern int fscrypt_do_page_crypto(const struct inode *inode,
+ fscrypt_direction_t rw, u64 lblk_num,
+ struct page *src_page,
+ struct page *dest_page,
+ unsigned int len, unsigned int offs,
+ gfp_t gfp_flags);
+extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
+ gfp_t gfp_flags);
#endif /* _FSCRYPT_PRIVATE_H */
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
index 95cd4c3b06c3..8cdfddce2b34 100644
--- a/fs/crypto/keyinfo.c
+++ b/fs/crypto/keyinfo.c
@@ -77,28 +77,25 @@ out:
static int validate_user_key(struct fscrypt_info *crypt_info,
struct fscrypt_context *ctx, u8 *raw_key,
- u8 *prefix, int prefix_size)
+ const char *prefix)
{
- u8 *full_key_descriptor;
+ char *description;
struct key *keyring_key;
struct fscrypt_key *master_key;
const struct user_key_payload *ukp;
- int full_key_len = prefix_size + (FS_KEY_DESCRIPTOR_SIZE * 2) + 1;
int res;
- full_key_descriptor = kmalloc(full_key_len, GFP_NOFS);
- if (!full_key_descriptor)
+ description = kasprintf(GFP_NOFS, "%s%*phN", prefix,
+ FS_KEY_DESCRIPTOR_SIZE,
+ ctx->master_key_descriptor);
+ if (!description)
return -ENOMEM;
- memcpy(full_key_descriptor, prefix, prefix_size);
- sprintf(full_key_descriptor + prefix_size,
- "%*phN", FS_KEY_DESCRIPTOR_SIZE,
- ctx->master_key_descriptor);
- full_key_descriptor[full_key_len - 1] = '\0';
- keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
- kfree(full_key_descriptor);
+ keyring_key = request_key(&key_type_logon, description, NULL);
+ kfree(description);
if (IS_ERR(keyring_key))
return PTR_ERR(keyring_key);
+ down_read(&keyring_key->sem);
if (keyring_key->type != &key_type_logon) {
printk_once(KERN_WARNING
@@ -106,11 +103,9 @@ static int validate_user_key(struct fscrypt_info *crypt_info,
res = -ENOKEY;
goto out;
}
- down_read(&keyring_key->sem);
- ukp = user_key_payload(keyring_key);
+ ukp = user_key_payload_locked(keyring_key);
if (ukp->datalen != sizeof(struct fscrypt_key)) {
res = -EINVAL;
- up_read(&keyring_key->sem);
goto out;
}
master_key = (struct fscrypt_key *)ukp->data;
@@ -121,17 +116,11 @@ static int validate_user_key(struct fscrypt_info *crypt_info,
"%s: key size incorrect: %d\n",
__func__, master_key->size);
res = -ENOKEY;
- up_read(&keyring_key->sem);
goto out;
}
res = derive_key_aes(ctx->nonce, master_key->raw, raw_key);
- up_read(&keyring_key->sem);
- if (res)
- goto out;
-
- crypt_info->ci_keyring_key = keyring_key;
- return 0;
out:
+ up_read(&keyring_key->sem);
key_put(keyring_key);
return res;
}
@@ -173,12 +162,11 @@ static void put_crypt_info(struct fscrypt_info *ci)
if (!ci)
return;
- key_put(ci->ci_keyring_key);
crypto_free_skcipher(ci->ci_ctfm);
kmem_cache_free(fscrypt_info_cachep, ci);
}
-int fscrypt_get_crypt_info(struct inode *inode)
+int fscrypt_get_encryption_info(struct inode *inode)
{
struct fscrypt_info *crypt_info;
struct fscrypt_context ctx;
@@ -188,30 +176,27 @@ int fscrypt_get_crypt_info(struct inode *inode)
u8 *raw_key = NULL;
int res;
+ if (inode->i_crypt_info)
+ return 0;
+
res = fscrypt_initialize(inode->i_sb->s_cop->flags);
if (res)
return res;
if (!inode->i_sb->s_cop->get_context)
return -EOPNOTSUPP;
-retry:
- crypt_info = ACCESS_ONCE(inode->i_crypt_info);
- if (crypt_info) {
- if (!crypt_info->ci_keyring_key ||
- key_validate(crypt_info->ci_keyring_key) == 0)
- return 0;
- fscrypt_put_encryption_info(inode, crypt_info);
- goto retry;
- }
res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
if (res < 0) {
- if (!fscrypt_dummy_context_enabled(inode))
+ if (!fscrypt_dummy_context_enabled(inode) ||
+ inode->i_sb->s_cop->is_encrypted(inode))
return res;
+ /* Fake up a context for an unencrypted directory */
+ memset(&ctx, 0, sizeof(ctx));
ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1;
ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS;
ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS;
- ctx.flags = 0;
+ memset(ctx.master_key_descriptor, 0x42, FS_KEY_DESCRIPTOR_SIZE);
} else if (res != sizeof(ctx)) {
return -EINVAL;
}
@@ -230,7 +215,6 @@ retry:
crypt_info->ci_data_mode = ctx.contents_encryption_mode;
crypt_info->ci_filename_mode = ctx.filenames_encryption_mode;
crypt_info->ci_ctfm = NULL;
- crypt_info->ci_keyring_key = NULL;
memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
sizeof(crypt_info->ci_master_key));
@@ -247,21 +231,10 @@ retry:
if (!raw_key)
goto out;
- if (fscrypt_dummy_context_enabled(inode)) {
- memset(raw_key, 0x42, keysize/2);
- memset(raw_key+keysize/2, 0x24, keysize - (keysize/2));
- goto got_key;
- }
-
- res = validate_user_key(crypt_info, &ctx, raw_key,
- FS_KEY_DESC_PREFIX, FS_KEY_DESC_PREFIX_SIZE);
+ res = validate_user_key(crypt_info, &ctx, raw_key, FS_KEY_DESC_PREFIX);
if (res && inode->i_sb->s_cop->key_prefix) {
- u8 *prefix = NULL;
- int prefix_size, res2;
-
- prefix_size = inode->i_sb->s_cop->key_prefix(inode, &prefix);
- res2 = validate_user_key(crypt_info, &ctx, raw_key,
- prefix, prefix_size);
+ int res2 = validate_user_key(crypt_info, &ctx, raw_key,
+ inode->i_sb->s_cop->key_prefix);
if (res2) {
if (res2 == -ENOKEY)
res = -ENOKEY;
@@ -270,7 +243,6 @@ retry:
} else if (res) {
goto out;
}
-got_key:
ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
if (!ctfm || IS_ERR(ctfm)) {
res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
@@ -286,14 +258,8 @@ got_key:
if (res)
goto out;
- kzfree(raw_key);
- raw_key = NULL;
- if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) != NULL) {
- put_crypt_info(crypt_info);
- goto retry;
- }
- return 0;
-
+ if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) == NULL)
+ crypt_info = NULL;
out:
if (res == -ENOKEY)
res = 0;
@@ -301,6 +267,7 @@ out:
kzfree(raw_key);
return res;
}
+EXPORT_SYMBOL(fscrypt_get_encryption_info);
void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
{
@@ -318,17 +285,3 @@ void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
put_crypt_info(ci);
}
EXPORT_SYMBOL(fscrypt_put_encryption_info);
-
-int fscrypt_get_encryption_info(struct inode *inode)
-{
- struct fscrypt_info *ci = inode->i_crypt_info;
-
- if (!ci ||
- (ci->ci_keyring_key &&
- (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
- (1 << KEY_FLAG_REVOKED) |
- (1 << KEY_FLAG_DEAD)))))
- return fscrypt_get_crypt_info(inode);
- return 0;
-}
-EXPORT_SYMBOL(fscrypt_get_encryption_info);
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index d6cd7ea4851d..4908906d54d5 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -13,73 +13,41 @@
#include <linux/mount.h>
#include "fscrypt_private.h"
-static int inode_has_encryption_context(struct inode *inode)
-{
- if (!inode->i_sb->s_cop->get_context)
- return 0;
- return (inode->i_sb->s_cop->get_context(inode, NULL, 0L) > 0);
-}
-
/*
- * check whether the policy is consistent with the encryption context
- * for the inode
+ * check whether an encryption policy is consistent with an encryption context
*/
-static int is_encryption_context_consistent_with_policy(struct inode *inode,
+static bool is_encryption_context_consistent_with_policy(
+ const struct fscrypt_context *ctx,
const struct fscrypt_policy *policy)
{
- struct fscrypt_context ctx;
- int res;
-
- if (!inode->i_sb->s_cop->get_context)
- return 0;
-
- res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
- if (res != sizeof(ctx))
- return 0;
-
- return (memcmp(ctx.master_key_descriptor, policy->master_key_descriptor,
- FS_KEY_DESCRIPTOR_SIZE) == 0 &&
- (ctx.flags == policy->flags) &&
- (ctx.contents_encryption_mode ==
- policy->contents_encryption_mode) &&
- (ctx.filenames_encryption_mode ==
- policy->filenames_encryption_mode));
+ return memcmp(ctx->master_key_descriptor, policy->master_key_descriptor,
+ FS_KEY_DESCRIPTOR_SIZE) == 0 &&
+ (ctx->flags == policy->flags) &&
+ (ctx->contents_encryption_mode ==
+ policy->contents_encryption_mode) &&
+ (ctx->filenames_encryption_mode ==
+ policy->filenames_encryption_mode);
}
static int create_encryption_context_from_policy(struct inode *inode,
const struct fscrypt_policy *policy)
{
struct fscrypt_context ctx;
- int res;
if (!inode->i_sb->s_cop->set_context)
return -EOPNOTSUPP;
- if (inode->i_sb->s_cop->prepare_context) {
- res = inode->i_sb->s_cop->prepare_context(inode);
- if (res)
- return res;
- }
-
ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1;
memcpy(ctx.master_key_descriptor, policy->master_key_descriptor,
FS_KEY_DESCRIPTOR_SIZE);
if (!fscrypt_valid_contents_enc_mode(
- policy->contents_encryption_mode)) {
- printk(KERN_WARNING
- "%s: Invalid contents encryption mode %d\n", __func__,
- policy->contents_encryption_mode);
+ policy->contents_encryption_mode))
return -EINVAL;
- }
if (!fscrypt_valid_filenames_enc_mode(
- policy->filenames_encryption_mode)) {
- printk(KERN_WARNING
- "%s: Invalid filenames encryption mode %d\n", __func__,
- policy->filenames_encryption_mode);
+ policy->filenames_encryption_mode))
return -EINVAL;
- }
if (policy->flags & ~FS_POLICY_FLAGS_VALID)
return -EINVAL;
@@ -98,6 +66,7 @@ int fscrypt_ioctl_set_policy(struct file *filp, const void __user *arg)
struct fscrypt_policy policy;
struct inode *inode = file_inode(filp);
int ret;
+ struct fscrypt_context ctx;
if (copy_from_user(&policy, arg, sizeof(policy)))
return -EFAULT;
@@ -114,9 +83,10 @@ int fscrypt_ioctl_set_policy(struct file *filp, const void __user *arg)
inode_lock(inode);
- if (!inode_has_encryption_context(inode)) {
+ ret = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
+ if (ret == -ENODATA) {
if (!S_ISDIR(inode->i_mode))
- ret = -EINVAL;
+ ret = -ENOTDIR;
else if (!inode->i_sb->s_cop->empty_dir)
ret = -EOPNOTSUPP;
else if (!inode->i_sb->s_cop->empty_dir(inode))
@@ -124,12 +94,14 @@ int fscrypt_ioctl_set_policy(struct file *filp, const void __user *arg)
else
ret = create_encryption_context_from_policy(inode,
&policy);
- } else if (!is_encryption_context_consistent_with_policy(inode,
- &policy)) {
- printk(KERN_WARNING
- "%s: Policy inconsistent with encryption context\n",
- __func__);
- ret = -EINVAL;
+ } else if (ret == sizeof(ctx) &&
+ is_encryption_context_consistent_with_policy(&ctx,
+ &policy)) {
+ /* The file already uses the same encryption policy. */
+ ret = 0;
+ } else if (ret >= 0 || ret == -ERANGE) {
+ /* The file already uses a different encryption policy. */
+ ret = -EEXIST;
}
inode_unlock(inode);
@@ -151,8 +123,10 @@ int fscrypt_ioctl_get_policy(struct file *filp, void __user *arg)
return -ENODATA;
res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
+ if (res < 0 && res != -ERANGE)
+ return res;
if (res != sizeof(ctx))
- return -ENODATA;
+ return -EINVAL;
if (ctx.format != FS_ENCRYPTION_CONTEXT_FORMAT_V1)
return -EINVAL;
@@ -217,9 +191,9 @@ EXPORT_SYMBOL(fscrypt_has_permitted_context);
* @parent: Parent inode from which the context is inherited.
* @child: Child inode that inherits the context from @parent.
* @fs_data: private data given by FS.
- * @preload: preload child i_crypt_info
+ * @preload: preload child i_crypt_info if true
*
- * Return: Zero on success, non-zero otherwise
+ * Return: 0 on success, -errno on failure
*/
int fscrypt_inherit_context(struct inode *parent, struct inode *child,
void *fs_data, bool preload)
@@ -240,19 +214,11 @@ int fscrypt_inherit_context(struct inode *parent, struct inode *child,
return -ENOKEY;
ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1;
- if (fscrypt_dummy_context_enabled(parent)) {
- ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS;
- ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS;
- ctx.flags = 0;
- memset(ctx.master_key_descriptor, 0x42, FS_KEY_DESCRIPTOR_SIZE);
- res = 0;
- } else {
- ctx.contents_encryption_mode = ci->ci_data_mode;
- ctx.filenames_encryption_mode = ci->ci_filename_mode;
- ctx.flags = ci->ci_flags;
- memcpy(ctx.master_key_descriptor, ci->ci_master_key,
- FS_KEY_DESCRIPTOR_SIZE);
- }
+ ctx.contents_encryption_mode = ci->ci_data_mode;
+ ctx.filenames_encryption_mode = ci->ci_filename_mode;
+ ctx.flags = ci->ci_flags;
+ memcpy(ctx.master_key_descriptor, ci->ci_master_key,
+ FS_KEY_DESCRIPTOR_SIZE);
get_random_bytes(ctx.nonce, FS_KEY_DERIVATION_NONCE_SIZE);
res = parent->i_sb->s_cop->set_context(child, &ctx,
sizeof(ctx), fs_data);