From 45eaab79678b9e27e08f0cf250eb2df9d6a48df0 Mon Sep 17 00:00:00 2001 From: Michael Halcrow Date: Tue, 16 Oct 2007 01:28:05 -0700 Subject: [PATCH] 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 Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ecryptfs/crypto.c | 40 +++++++++++++++++------------------ fs/ecryptfs/ecryptfs_kernel.h | 39 +++++++++++++++++++++++----------- fs/ecryptfs/inode.c | 7 +++--- fs/ecryptfs/mmap.c | 2 +- 4 files changed, 52 insertions(+), 36 deletions(-) diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 8e9b36df78..9127b80904 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -366,8 +366,8 @@ ecryptfs_extent_to_lwr_pg_idx_and_offset(unsigned long *lower_page_idx, int extents_per_page; bytes_occupied_by_headers_at_front = - ( crypt_stat->header_extent_size - * crypt_stat->num_header_extents_at_front ); + (crypt_stat->extent_size + * crypt_stat->num_header_extents_at_front); extents_occupied_by_headers_at_front = ( bytes_occupied_by_headers_at_front / 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; extent_offset = lower_extent_num % extents_per_page; (*byte_offset) = extent_offset * crypt_stat->extent_size; - ecryptfs_printk(KERN_DEBUG, " * crypt_stat->header_extent_size = " - "[%d]\n", crypt_stat->header_extent_size); + ecryptfs_printk(KERN_DEBUG, " * crypt_stat->extent_size = " + "[%d]\n", crypt_stat->extent_size); ecryptfs_printk(KERN_DEBUG, " * crypt_stat->" "num_header_extents_at_front = [%d]\n", 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; set_extent_mask_and_shift(crypt_stat); 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) crypt_stat->num_header_extents_at_front = 0; - else - crypt_stat->num_header_extents_at_front = 1; + else { + 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; 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 = (u16)crypt_stat->num_header_extents_at_front; 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); goto out; } - header_pages = ((crypt_stat->header_extent_size + header_pages = ((crypt_stat->extent_size * crypt_stat->num_header_extents_at_front) / 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; memcpy(&num_header_extents_at_front, virt, 2); 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 = (int)num_header_extents_at_front; - (*bytes_read) = 6; + (*bytes_read) = (sizeof(u32) + sizeof(u16)); if ((validate_header_size == ECRYPTFS_VALIDATE_HEADER_SIZE) - && ((crypt_stat->header_extent_size + && ((crypt_stat->extent_size * crypt_stat->num_header_extents_at_front) < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) { rc = -EINVAL; - ecryptfs_printk(KERN_WARNING, "Invalid header extent size: " - "[%d]\n", crypt_stat->header_extent_size); + printk(KERN_WARNING "Invalid number of header extents: [%zd]\n", + crypt_stat->num_header_extents_at_front); } 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) { - crypt_stat->header_extent_size = 4096; - crypt_stat->num_header_extents_at_front = 1; + crypt_stat->num_header_extents_at_front = 2; } /** diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index 78761e4bda..a618ab7764 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -38,7 +38,7 @@ /* Version verification for shared data structures w/ userspace */ #define ECRYPTFS_VERSION_MAJOR 0x00 #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 * module; userspace tools such as the mount helper read * ECRYPTFS_VERSIONING_MASK from a sysfs handle in order to determine @@ -67,8 +67,7 @@ #define ECRYPTFS_MAX_KEY_BYTES 64 #define ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 512 #define ECRYPTFS_DEFAULT_IV_BYTES 16 -#define ECRYPTFS_FILE_VERSION 0x02 -#define ECRYPTFS_DEFAULT_HEADER_EXTENT_SIZE 8192 +#define ECRYPTFS_FILE_VERSION 0x03 #define ECRYPTFS_DEFAULT_EXTENT_SIZE 4096 #define ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE 8192 #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 MAGIC_ECRYPTFS_MARKER 0x3c81b7f5 #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_KEY_BYTES 16 #define ECRYPTFS_DEFAULT_HASH "md5" @@ -238,7 +237,6 @@ struct ecryptfs_crypt_stat { u32 flags; unsigned int file_version; size_t iv_bytes; - size_t header_extent_size; size_t num_header_extents_at_front; size_t extent_size; /* Data extent size; default is 4096 */ 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 * 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 @@ -283,15 +292,21 @@ struct ecryptfs_dentry_info { struct ecryptfs_global_auth_tok { #define ECRYPTFS_AUTH_TOK_INVALID 0x00000001 u32 flags; - struct list_head mount_crypt_stat_list; /* Default auth_tok list for - * the mount_crypt_stat */ - struct key *global_auth_tok_key; /* The key from the user's keyring for - * the sig */ - struct ecryptfs_auth_tok *global_auth_tok; /* The key contents */ - unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1]; /* The key identifier */ + struct list_head mount_crypt_stat_list; + struct key *global_auth_tok_key; + struct ecryptfs_auth_tok *global_auth_tok; + unsigned char sig[ECRYPTFS_SIG_SIZE_HEX + 1]; }; /** + * 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 * the course of its operations. In order to avoid unnecessarily * destroying and initializing the same cipher repeatedly, eCryptfs @@ -301,7 +316,7 @@ struct ecryptfs_key_tfm { struct crypto_blkcipher *key_tfm; size_t key_size; 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]; }; diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index 131954b3fb..abac91c58b 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -392,7 +392,8 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry, dentry->d_sb)->mount_crypt_stat; if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) { 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)); else 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; - lower_size = ( crypt_stat->header_extent_size - * crypt_stat->num_header_extents_at_front ); + lower_size = (crypt_stat->extent_size + * crypt_stat->num_header_extents_at_front); if (upper_size != 0) { loff_t num_extents; diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index aaea55a61e..89dbbbbcce 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -301,7 +301,7 @@ static int ecryptfs_readpage(struct file *file, struct page *page) } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) { if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) { int num_pages_in_header_region = - (crypt_stat->header_extent_size + (crypt_stat->extent_size / PAGE_CACHE_SIZE); if (page->index < num_pages_in_header_region) { -- 2.39.5