eCryptfs: remove header_extent_size

There is no point to keeping a separate header_extent_size and an extent_size.
 The total size of the header can always be represented as some multiple of
the regular data extent size.

[randy.dunlap@oracle.com: ecryptfs: fix printk format warning]
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michael Halcrow 2007-10-16 01:28:05 -07:00 committed by Linus Torvalds
parent e9f6a99cb8
commit 45eaab7967
4 changed files with 52 additions and 36 deletions

View file

@ -366,8 +366,8 @@ ecryptfs_extent_to_lwr_pg_idx_and_offset(unsigned long *lower_page_idx,
int extents_per_page; int extents_per_page;
bytes_occupied_by_headers_at_front = bytes_occupied_by_headers_at_front =
( crypt_stat->header_extent_size (crypt_stat->extent_size
* crypt_stat->num_header_extents_at_front ); * crypt_stat->num_header_extents_at_front);
extents_occupied_by_headers_at_front = extents_occupied_by_headers_at_front =
( bytes_occupied_by_headers_at_front ( bytes_occupied_by_headers_at_front
/ crypt_stat->extent_size ); / crypt_stat->extent_size );
@ -376,8 +376,8 @@ ecryptfs_extent_to_lwr_pg_idx_and_offset(unsigned long *lower_page_idx,
(*lower_page_idx) = lower_extent_num / extents_per_page; (*lower_page_idx) = lower_extent_num / extents_per_page;
extent_offset = lower_extent_num % extents_per_page; extent_offset = lower_extent_num % extents_per_page;
(*byte_offset) = extent_offset * crypt_stat->extent_size; (*byte_offset) = extent_offset * crypt_stat->extent_size;
ecryptfs_printk(KERN_DEBUG, " * crypt_stat->header_extent_size = " ecryptfs_printk(KERN_DEBUG, " * crypt_stat->extent_size = "
"[%d]\n", crypt_stat->header_extent_size); "[%d]\n", crypt_stat->extent_size);
ecryptfs_printk(KERN_DEBUG, " * crypt_stat->" ecryptfs_printk(KERN_DEBUG, " * crypt_stat->"
"num_header_extents_at_front = [%d]\n", "num_header_extents_at_front = [%d]\n",
crypt_stat->num_header_extents_at_front); crypt_stat->num_header_extents_at_front);
@ -899,15 +899,17 @@ void ecryptfs_set_default_sizes(struct ecryptfs_crypt_stat *crypt_stat)
crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE; crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
set_extent_mask_and_shift(crypt_stat); set_extent_mask_and_shift(crypt_stat);
crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES; crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES;
if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
crypt_stat->header_extent_size =
ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
} else
crypt_stat->header_extent_size = PAGE_CACHE_SIZE;
if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
crypt_stat->num_header_extents_at_front = 0; crypt_stat->num_header_extents_at_front = 0;
else else {
crypt_stat->num_header_extents_at_front = 1; if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)
crypt_stat->num_header_extents_at_front =
(ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE
/ crypt_stat->extent_size);
else
crypt_stat->num_header_extents_at_front =
(PAGE_CACHE_SIZE / crypt_stat->extent_size);
}
} }
/** /**
@ -1319,7 +1321,7 @@ ecryptfs_write_header_metadata(char *virt,
u32 header_extent_size; u32 header_extent_size;
u16 num_header_extents_at_front; u16 num_header_extents_at_front;
header_extent_size = (u32)crypt_stat->header_extent_size; header_extent_size = (u32)crypt_stat->extent_size;
num_header_extents_at_front = num_header_extents_at_front =
(u16)crypt_stat->num_header_extents_at_front; (u16)crypt_stat->num_header_extents_at_front;
header_extent_size = cpu_to_be32(header_extent_size); header_extent_size = cpu_to_be32(header_extent_size);
@ -1415,7 +1417,7 @@ ecryptfs_write_metadata_to_contents(struct ecryptfs_crypt_stat *crypt_stat,
set_fs(oldfs); set_fs(oldfs);
goto out; goto out;
} }
header_pages = ((crypt_stat->header_extent_size header_pages = ((crypt_stat->extent_size
* crypt_stat->num_header_extents_at_front) * crypt_stat->num_header_extents_at_front)
/ PAGE_CACHE_SIZE); / PAGE_CACHE_SIZE);
memset(page_virt, 0, PAGE_CACHE_SIZE); memset(page_virt, 0, PAGE_CACHE_SIZE);
@ -1532,17 +1534,16 @@ static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat,
virt += 4; virt += 4;
memcpy(&num_header_extents_at_front, virt, 2); memcpy(&num_header_extents_at_front, virt, 2);
num_header_extents_at_front = be16_to_cpu(num_header_extents_at_front); num_header_extents_at_front = be16_to_cpu(num_header_extents_at_front);
crypt_stat->header_extent_size = (int)header_extent_size;
crypt_stat->num_header_extents_at_front = crypt_stat->num_header_extents_at_front =
(int)num_header_extents_at_front; (int)num_header_extents_at_front;
(*bytes_read) = 6; (*bytes_read) = (sizeof(u32) + sizeof(u16));
if ((validate_header_size == ECRYPTFS_VALIDATE_HEADER_SIZE) if ((validate_header_size == ECRYPTFS_VALIDATE_HEADER_SIZE)
&& ((crypt_stat->header_extent_size && ((crypt_stat->extent_size
* crypt_stat->num_header_extents_at_front) * crypt_stat->num_header_extents_at_front)
< ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) { < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) {
rc = -EINVAL; rc = -EINVAL;
ecryptfs_printk(KERN_WARNING, "Invalid header extent size: " printk(KERN_WARNING "Invalid number of header extents: [%zd]\n",
"[%d]\n", crypt_stat->header_extent_size); crypt_stat->num_header_extents_at_front);
} }
return rc; return rc;
} }
@ -1557,8 +1558,7 @@ static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat,
*/ */
static void set_default_header_data(struct ecryptfs_crypt_stat *crypt_stat) static void set_default_header_data(struct ecryptfs_crypt_stat *crypt_stat)
{ {
crypt_stat->header_extent_size = 4096; crypt_stat->num_header_extents_at_front = 2;
crypt_stat->num_header_extents_at_front = 1;
} }
/** /**

View file

@ -38,7 +38,7 @@
/* Version verification for shared data structures w/ userspace */ /* Version verification for shared data structures w/ userspace */
#define ECRYPTFS_VERSION_MAJOR 0x00 #define ECRYPTFS_VERSION_MAJOR 0x00
#define ECRYPTFS_VERSION_MINOR 0x04 #define ECRYPTFS_VERSION_MINOR 0x04
#define ECRYPTFS_SUPPORTED_FILE_VERSION 0x02 #define ECRYPTFS_SUPPORTED_FILE_VERSION 0x03
/* These flags indicate which features are supported by the kernel /* These flags indicate which features are supported by the kernel
* module; userspace tools such as the mount helper read * module; userspace tools such as the mount helper read
* ECRYPTFS_VERSIONING_MASK from a sysfs handle in order to determine * ECRYPTFS_VERSIONING_MASK from a sysfs handle in order to determine
@ -67,8 +67,7 @@
#define ECRYPTFS_MAX_KEY_BYTES 64 #define ECRYPTFS_MAX_KEY_BYTES 64
#define ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 512 #define ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 512
#define ECRYPTFS_DEFAULT_IV_BYTES 16 #define ECRYPTFS_DEFAULT_IV_BYTES 16
#define ECRYPTFS_FILE_VERSION 0x02 #define ECRYPTFS_FILE_VERSION 0x03
#define ECRYPTFS_DEFAULT_HEADER_EXTENT_SIZE 8192
#define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096 #define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096
#define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192 #define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192
#define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32 #define ECRYPTFS_DEFAULT_MSG_CTX_ELEMS 32
@ -201,7 +200,7 @@ ecryptfs_get_key_payload_data(struct key *key)
#define ECRYPTFS_SALT_BYTES 2 #define ECRYPTFS_SALT_BYTES 2
#define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5 #define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
#define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8 /* 4*2 */ #define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8 /* 4*2 */
#define ECRYPTFS_FILE_SIZE_BYTES 8 #define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
#define ECRYPTFS_DEFAULT_CIPHER "aes" #define ECRYPTFS_DEFAULT_CIPHER "aes"
#define ECRYPTFS_DEFAULT_KEY_BYTES 16 #define ECRYPTFS_DEFAULT_KEY_BYTES 16
#define ECRYPTFS_DEFAULT_HASH "md5" #define ECRYPTFS_DEFAULT_HASH "md5"
@ -238,7 +237,6 @@ struct ecryptfs_crypt_stat {
u32 flags; u32 flags;
unsigned int file_version; unsigned int file_version;
size_t iv_bytes; size_t iv_bytes;
size_t header_extent_size;
size_t num_header_extents_at_front; size_t num_header_extents_at_front;
size_t extent_size; /* Data extent size; default is 4096 */ size_t extent_size; /* Data extent size; default is 4096 */
size_t key_size; size_t key_size;
@ -273,6 +271,17 @@ struct ecryptfs_dentry_info {
}; };
/** /**
* ecryptfs_global_auth_tok - A key used to encrypt all new files under the mountpoint
* @flags: Status flags
* @mount_crypt_stat_list: These auth_toks hang off the mount-wide
* cryptographic context. Every time a new
* inode comes into existence, eCryptfs copies
* the auth_toks on that list to the set of
* auth_toks on the inode's crypt_stat
* @global_auth_tok_key: The key from the user's keyring for the sig
* @global_auth_tok: The key contents
* @sig: The key identifier
*
* ecryptfs_global_auth_tok structs refer to authentication token keys * ecryptfs_global_auth_tok structs refer to authentication token keys
* in the user keyring that apply to newly created files. A list of * in the user keyring that apply to newly created files. A list of
* these objects hangs off of the mount_crypt_stat struct for any * these objects hangs off of the mount_crypt_stat struct for any
@ -283,15 +292,21 @@ struct ecryptfs_dentry_info {
struct ecryptfs_global_auth_tok { struct ecryptfs_global_auth_tok {
#define ECRYPTFS_AUTH_TOK_INVALID 0x00000001 #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001
u32 flags; u32 flags;
struct list_head mount_crypt_stat_list; /* Default auth_tok list for struct list_head mount_crypt_stat_list;
* the mount_crypt_stat */ struct key *global_auth_tok_key;
struct key *global_auth_tok_key; /* The key from the user's keyring for struct ecryptfs_auth_tok *global_auth_tok;
* the sig */ unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1];
struct ecryptfs_auth_tok *global_auth_tok; /* The key contents */
unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1]; /* The key identifier */
}; };
/** /**
* ecryptfs_key_tfm - Persistent key tfm
* @key_tfm: crypto API handle to the key
* @key_size: Key size in bytes
* @key_tfm_mutex: Mutex to ensure only one operation in eCryptfs is
* using the persistent TFM at any point in time
* @key_tfm_list: Handle to hang this off the module-wide TFM list
* @cipher_name: String name for the cipher for this TFM
*
* Typically, eCryptfs will use the same ciphers repeatedly throughout * Typically, eCryptfs will use the same ciphers repeatedly throughout
* the course of its operations. In order to avoid unnecessarily * the course of its operations. In order to avoid unnecessarily
* destroying and initializing the same cipher repeatedly, eCryptfs * destroying and initializing the same cipher repeatedly, eCryptfs
@ -301,7 +316,7 @@ struct ecryptfs_key_tfm {
struct crypto_blkcipher *key_tfm; struct crypto_blkcipher *key_tfm;
size_t key_size; size_t key_size;
struct mutex key_tfm_mutex; struct mutex key_tfm_mutex;
struct list_head key_tfm_list; /* The module's tfm list */ struct list_head key_tfm_list;
unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1]; unsigned char cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1];
}; };

View file

@ -392,7 +392,8 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
dentry->d_sb)->mount_crypt_stat; dentry->d_sb)->mount_crypt_stat;
if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) {
if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
file_size = (crypt_stat->header_extent_size file_size = ((crypt_stat->extent_size
* crypt_stat->num_header_extents_at_front)
+ i_size_read(lower_dentry->d_inode)); + i_size_read(lower_dentry->d_inode));
else else
file_size = i_size_read(lower_dentry->d_inode); file_size = i_size_read(lower_dentry->d_inode);
@ -722,8 +723,8 @@ upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
{ {
loff_t lower_size; loff_t lower_size;
lower_size = ( crypt_stat->header_extent_size lower_size = (crypt_stat->extent_size
* crypt_stat->num_header_extents_at_front ); * crypt_stat->num_header_extents_at_front);
if (upper_size != 0) { if (upper_size != 0) {
loff_t num_extents; loff_t num_extents;

View file

@ -301,7 +301,7 @@ static int ecryptfs_readpage(struct file *file, struct page *page)
} else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) { } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) {
if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) { if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
int num_pages_in_header_region = int num_pages_in_header_region =
(crypt_stat->header_extent_size (crypt_stat->extent_size
/ PAGE_CACHE_SIZE); / PAGE_CACHE_SIZE);
if (page->index < num_pages_in_header_region) { if (page->index < num_pages_in_header_region) {