diff options
Diffstat (limited to 'fs/ecryptfs/main.c')
| -rw-r--r-- | fs/ecryptfs/main.c | 910 |
1 files changed, 457 insertions, 453 deletions
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index a98497264fe..1b119d3bf92 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -30,13 +30,13 @@ #include <linux/namei.h> #include <linux/skbuff.h> #include <linux/crypto.h> -#include <linux/netlink.h> #include <linux/mount.h> -#include <linux/dcache.h> #include <linux/pagemap.h> #include <linux/key.h> #include <linux/parser.h> #include <linux/fs_stack.h> +#include <linux/slab.h> +#include <linux/magic.h> #include "ecryptfs_kernel.h" /** @@ -50,8 +50,7 @@ MODULE_PARM_DESC(ecryptfs_verbosity, "0, which is Quiet)"); /** - * Module parameter that defines the number of netlink message buffer - * elements + * Module parameter that defines the number of message buffer elements */ unsigned int ecryptfs_message_buf_len = ECRYPTFS_DEFAULT_MSG_CTX_ELEMS; @@ -61,9 +60,9 @@ MODULE_PARM_DESC(ecryptfs_message_buf_len, /** * Module parameter that defines the maximum guaranteed amount of time to wait - * for a response through netlink. The actual sleep time will be, more than + * for a response from ecryptfsd. The actual sleep time will be, more than * likely, a small amount greater than this specified value, but only less if - * the netlink message successfully arrives. + * the message successfully arrives. */ signed long ecryptfs_message_wait_timeout = ECRYPTFS_MAX_MSG_CTX_TTL / HZ; @@ -84,8 +83,6 @@ module_param(ecryptfs_number_of_users, uint, 0); MODULE_PARM_DESC(ecryptfs_number_of_users, "An estimate of the number of " "concurrent users of eCryptfs"); -unsigned int ecryptfs_transport = ECRYPTFS_DEFAULT_TRANSPORT; - void __ecryptfs_printk(const char *fmt, ...) { va_list args; @@ -99,122 +96,149 @@ void __ecryptfs_printk(const char *fmt, ...) } /** - * ecryptfs_interpose - * @lower_dentry: Existing dentry in the lower filesystem - * @dentry: ecryptfs' dentry - * @sb: ecryptfs's super_block - * @flag: If set to true, then d_add is called, else d_instantiate is called + * ecryptfs_init_lower_file + * @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with + * the lower dentry and the lower mount set + * + * eCryptfs only ever keeps a single open file for every lower + * inode. All I/O operations to the lower inode occur through that + * file. When the first eCryptfs dentry that interposes with the first + * lower dentry for that inode is created, this function creates the + * lower file struct and associates it with the eCryptfs + * inode. When all eCryptfs files associated with the inode are released, the + * file is closed. + * + * The lower file will be opened with read/write permissions, if + * possible. Otherwise, it is opened read-only. * - * Interposes upper and lower dentries. + * This function does nothing if a lower file is already + * associated with the eCryptfs inode. * * Returns zero on success; non-zero otherwise */ -int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry, - struct super_block *sb, int flag) +static int ecryptfs_init_lower_file(struct dentry *dentry, + struct file **lower_file) { - struct inode *lower_inode; - struct inode *inode; - int rc = 0; + const struct cred *cred = current_cred(); + struct path *path = ecryptfs_dentry_to_lower_path(dentry); + int rc; - lower_inode = lower_dentry->d_inode; - if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb)) { - rc = -EXDEV; - goto out; - } - if (!igrab(lower_inode)) { - rc = -ESTALE; - goto out; + rc = ecryptfs_privileged_open(lower_file, path->dentry, path->mnt, + cred); + if (rc) { + printk(KERN_ERR "Error opening lower file " + "for lower_dentry [0x%p] and lower_mnt [0x%p]; " + "rc = [%d]\n", path->dentry, path->mnt, rc); + (*lower_file) = NULL; } - inode = iget5_locked(sb, (unsigned long)lower_inode, - ecryptfs_inode_test, ecryptfs_inode_set, - lower_inode); - if (!inode) { - rc = -EACCES; - iput(lower_inode); - goto out; + return rc; +} + +int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode) +{ + struct ecryptfs_inode_info *inode_info; + int count, rc = 0; + + inode_info = ecryptfs_inode_to_private(inode); + mutex_lock(&inode_info->lower_file_mutex); + count = atomic_inc_return(&inode_info->lower_file_count); + if (WARN_ON_ONCE(count < 1)) + rc = -EINVAL; + else if (count == 1) { + rc = ecryptfs_init_lower_file(dentry, + &inode_info->lower_file); + if (rc) + atomic_set(&inode_info->lower_file_count, 0); } - if (inode->i_state & I_NEW) - unlock_new_inode(inode); - else - iput(lower_inode); - if (S_ISLNK(lower_inode->i_mode)) - inode->i_op = &ecryptfs_symlink_iops; - else if (S_ISDIR(lower_inode->i_mode)) - inode->i_op = &ecryptfs_dir_iops; - if (S_ISDIR(lower_inode->i_mode)) - inode->i_fop = &ecryptfs_dir_fops; - if (special_file(lower_inode->i_mode)) - init_special_inode(inode, lower_inode->i_mode, - lower_inode->i_rdev); - dentry->d_op = &ecryptfs_dops; - if (flag) - d_add(dentry, inode); - else - d_instantiate(dentry, inode); - fsstack_copy_attr_all(inode, lower_inode, NULL); - /* This size will be overwritten for real files w/ headers and - * other metadata */ - fsstack_copy_inode_size(inode, lower_inode); -out: + mutex_unlock(&inode_info->lower_file_mutex); return rc; } -enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig, ecryptfs_opt_debug, - ecryptfs_opt_ecryptfs_debug, ecryptfs_opt_cipher, - ecryptfs_opt_ecryptfs_cipher, ecryptfs_opt_ecryptfs_key_bytes, +void ecryptfs_put_lower_file(struct inode *inode) +{ + struct ecryptfs_inode_info *inode_info; + + inode_info = ecryptfs_inode_to_private(inode); + if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count, + &inode_info->lower_file_mutex)) { + filemap_write_and_wait(inode->i_mapping); + fput(inode_info->lower_file); + inode_info->lower_file = NULL; + mutex_unlock(&inode_info->lower_file_mutex); + } +} + +enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig, + ecryptfs_opt_cipher, ecryptfs_opt_ecryptfs_cipher, + ecryptfs_opt_ecryptfs_key_bytes, ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata, - ecryptfs_opt_encrypted_view, ecryptfs_opt_err }; + ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig, + ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes, + ecryptfs_opt_unlink_sigs, ecryptfs_opt_mount_auth_tok_only, + ecryptfs_opt_check_dev_ruid, + ecryptfs_opt_err }; -static match_table_t tokens = { +static const match_table_t tokens = { {ecryptfs_opt_sig, "sig=%s"}, {ecryptfs_opt_ecryptfs_sig, "ecryptfs_sig=%s"}, - {ecryptfs_opt_debug, "debug=%u"}, - {ecryptfs_opt_ecryptfs_debug, "ecryptfs_debug=%u"}, {ecryptfs_opt_cipher, "cipher=%s"}, {ecryptfs_opt_ecryptfs_cipher, "ecryptfs_cipher=%s"}, {ecryptfs_opt_ecryptfs_key_bytes, "ecryptfs_key_bytes=%u"}, {ecryptfs_opt_passthrough, "ecryptfs_passthrough"}, {ecryptfs_opt_xattr_metadata, "ecryptfs_xattr_metadata"}, {ecryptfs_opt_encrypted_view, "ecryptfs_encrypted_view"}, + {ecryptfs_opt_fnek_sig, "ecryptfs_fnek_sig=%s"}, + {ecryptfs_opt_fn_cipher, "ecryptfs_fn_cipher=%s"}, + {ecryptfs_opt_fn_cipher_key_bytes, "ecryptfs_fn_key_bytes=%u"}, + {ecryptfs_opt_unlink_sigs, "ecryptfs_unlink_sigs"}, + {ecryptfs_opt_mount_auth_tok_only, "ecryptfs_mount_auth_tok_only"}, + {ecryptfs_opt_check_dev_ruid, "ecryptfs_check_dev_ruid"}, {ecryptfs_opt_err, NULL} }; -/** - * ecryptfs_verify_version - * @version: The version number to confirm - * - * Returns zero on good version; non-zero otherwise - */ -static int ecryptfs_verify_version(u16 version) +static int ecryptfs_init_global_auth_toks( + struct ecryptfs_mount_crypt_stat *mount_crypt_stat) { + struct ecryptfs_global_auth_tok *global_auth_tok; + struct ecryptfs_auth_tok *auth_tok; int rc = 0; - unsigned char major; - unsigned char minor; - - major = ((version >> 8) & 0xFF); - minor = (version & 0xFF); - if (major != ECRYPTFS_VERSION_MAJOR) { - ecryptfs_printk(KERN_ERR, "Major version number mismatch. " - "Expected [%d]; got [%d]\n", - ECRYPTFS_VERSION_MAJOR, major); - rc = -EINVAL; - goto out; - } - if (minor != ECRYPTFS_VERSION_MINOR) { - ecryptfs_printk(KERN_ERR, "Minor version number mismatch. " - "Expected [%d]; got [%d]\n", - ECRYPTFS_VERSION_MINOR, minor); - rc = -EINVAL; - goto out; + + list_for_each_entry(global_auth_tok, + &mount_crypt_stat->global_auth_tok_list, + mount_crypt_stat_list) { + rc = ecryptfs_keyring_auth_tok_for_sig( + &global_auth_tok->global_auth_tok_key, &auth_tok, + global_auth_tok->sig); + if (rc) { + printk(KERN_ERR "Could not find valid key in user " + "session keyring for sig specified in mount " + "option: [%s]\n", global_auth_tok->sig); + global_auth_tok->flags |= ECRYPTFS_AUTH_TOK_INVALID; + goto out; + } else { + global_auth_tok->flags &= ~ECRYPTFS_AUTH_TOK_INVALID; + up_write(&(global_auth_tok->global_auth_tok_key)->sem); + } } out: return rc; } +static void ecryptfs_init_mount_crypt_stat( + struct ecryptfs_mount_crypt_stat *mount_crypt_stat) +{ + memset((void *)mount_crypt_stat, 0, + sizeof(struct ecryptfs_mount_crypt_stat)); + INIT_LIST_HEAD(&mount_crypt_stat->global_auth_tok_list); + mutex_init(&mount_crypt_stat->global_auth_tok_list_mutex); + mount_crypt_stat->flags |= ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED; +} + /** * ecryptfs_parse_options * @sb: The ecryptfs super block - * @options: The options pased to the kernel + * @options: The options passed to the kernel + * @check_ruid: set to 1 if device uid should be checked against the ruid * * Parse mount options: * debug=N - ecryptfs_verbosity level for debug output @@ -230,32 +254,40 @@ out: * * Returns zero on success; non-zero on error */ -static int ecryptfs_parse_options(struct super_block *sb, char *options) +static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options, + uid_t *check_ruid) { char *p; int rc = 0; int sig_set = 0; int cipher_name_set = 0; + int fn_cipher_name_set = 0; int cipher_key_bytes; int cipher_key_bytes_set = 0; - struct key *auth_tok_key = NULL; - struct ecryptfs_auth_tok *auth_tok = NULL; + int fn_cipher_key_bytes; + int fn_cipher_key_bytes_set = 0; struct ecryptfs_mount_crypt_stat *mount_crypt_stat = - &ecryptfs_superblock_to_private(sb)->mount_crypt_stat; + &sbi->mount_crypt_stat; substring_t args[MAX_OPT_ARGS]; int token; char *sig_src; - char *sig_dst; - char *debug_src; char *cipher_name_dst; char *cipher_name_src; + char *fn_cipher_name_dst; + char *fn_cipher_name_src; + char *fnek_dst; + char *fnek_src; char *cipher_key_bytes_src; - int cipher_name_len; + char *fn_cipher_key_bytes_src; + u8 cipher_code; + + *check_ruid = 0; if (!options) { rc = -EINVAL; goto out; } + ecryptfs_init_mount_crypt_stat(mount_crypt_stat); while ((p = strsep(&options, ",")) != NULL) { if (!*p) continue; @@ -264,26 +296,15 @@ static int ecryptfs_parse_options(struct super_block *sb, char *options) case ecryptfs_opt_sig: case ecryptfs_opt_ecryptfs_sig: sig_src = args[0].from; - sig_dst = - mount_crypt_stat->global_auth_tok_sig; - memcpy(sig_dst, sig_src, ECRYPTFS_SIG_SIZE_HEX); - sig_dst[ECRYPTFS_SIG_SIZE_HEX] = '\0'; - ecryptfs_printk(KERN_DEBUG, - "The mount_crypt_stat " - "global_auth_tok_sig set to: " - "[%s]\n", sig_dst); + rc = ecryptfs_add_global_auth_tok(mount_crypt_stat, + sig_src, 0); + if (rc) { + printk(KERN_ERR "Error attempting to register " + "global sig; rc = [%d]\n", rc); + goto out; + } sig_set = 1; break; - case ecryptfs_opt_debug: - case ecryptfs_opt_ecryptfs_debug: - debug_src = args[0].from; - ecryptfs_verbosity = - (int)simple_strtol(debug_src, &debug_src, - 0); - ecryptfs_printk(KERN_DEBUG, - "Verbosity set to [%d]" "\n", - ecryptfs_verbosity); - break; case ecryptfs_opt_cipher: case ecryptfs_opt_ecryptfs_cipher: cipher_name_src = args[0].from; @@ -292,10 +313,7 @@ static int ecryptfs_parse_options(struct super_block *sb, char *options) global_default_cipher_name; strncpy(cipher_name_dst, cipher_name_src, ECRYPTFS_MAX_CIPHER_NAME_SIZE); - ecryptfs_printk(KERN_DEBUG, - "The mount_crypt_stat " - "global_default_cipher_name set to: " - "[%s]\n", cipher_name_dst); + cipher_name_dst[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0'; cipher_name_set = 1; break; case ecryptfs_opt_ecryptfs_key_bytes: @@ -305,11 +323,6 @@ static int ecryptfs_parse_options(struct super_block *sb, char *options) &cipher_key_bytes_src, 0); mount_crypt_stat->global_default_cipher_key_size = cipher_key_bytes; - ecryptfs_printk(KERN_DEBUG, - "The mount_crypt_stat " - "global_default_cipher_key_size " - "set to: [%d]\n", mount_crypt_stat-> - global_default_cipher_key_size); cipher_key_bytes_set = 1; break; case ecryptfs_opt_passthrough: @@ -326,231 +339,268 @@ static int ecryptfs_parse_options(struct super_block *sb, char *options) mount_crypt_stat->flags |= ECRYPTFS_ENCRYPTED_VIEW_ENABLED; break; + case ecryptfs_opt_fnek_sig: + fnek_src = args[0].from; + fnek_dst = + mount_crypt_stat->global_default_fnek_sig; + strncpy(fnek_dst, fnek_src, ECRYPTFS_SIG_SIZE_HEX); + mount_crypt_stat->global_default_fnek_sig[ + ECRYPTFS_SIG_SIZE_HEX] = '\0'; + rc = ecryptfs_add_global_auth_tok( + mount_crypt_stat, + mount_crypt_stat->global_default_fnek_sig, + ECRYPTFS_AUTH_TOK_FNEK); + if (rc) { + printk(KERN_ERR "Error attempting to register " + "global fnek sig [%s]; rc = [%d]\n", + mount_crypt_stat->global_default_fnek_sig, + rc); + goto out; + } + mount_crypt_stat->flags |= + (ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES + | ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK); + break; + case ecryptfs_opt_fn_cipher: + fn_cipher_name_src = args[0].from; + fn_cipher_name_dst = + mount_crypt_stat->global_default_fn_cipher_name; + strncpy(fn_cipher_name_dst, fn_cipher_name_src, + ECRYPTFS_MAX_CIPHER_NAME_SIZE); + mount_crypt_stat->global_default_fn_cipher_name[ + ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0'; + fn_cipher_name_set = 1; + break; + case ecryptfs_opt_fn_cipher_key_bytes: + fn_cipher_key_bytes_src = args[0].from; + fn_cipher_key_bytes = + (int)simple_strtol(fn_cipher_key_bytes_src, + &fn_cipher_key_bytes_src, 0); + mount_crypt_stat->global_default_fn_cipher_key_bytes = + fn_cipher_key_bytes; + fn_cipher_key_bytes_set = 1; + break; + case ecryptfs_opt_unlink_sigs: + mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS; + break; + case ecryptfs_opt_mount_auth_tok_only: + mount_crypt_stat->flags |= + ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY; + break; + case ecryptfs_opt_check_dev_ruid: + *check_ruid = 1; + break; case ecryptfs_opt_err: default: - ecryptfs_printk(KERN_WARNING, - "eCryptfs: unrecognized option '%s'\n", - p); + printk(KERN_WARNING + "%s: eCryptfs: unrecognized option [%s]\n", + __func__, p); } } - /* Do not support lack of mount-wide signature in 0.1 - * release */ if (!sig_set) { rc = -EINVAL; - ecryptfs_printk(KERN_ERR, "You must supply a valid " - "passphrase auth tok signature as a mount " + ecryptfs_printk(KERN_ERR, "You must supply at least one valid " + "auth tok signature as a mount " "parameter; see the eCryptfs README\n"); goto out; } if (!cipher_name_set) { - cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER); - if (unlikely(cipher_name_len - >= ECRYPTFS_MAX_CIPHER_NAME_SIZE)) { - rc = -EINVAL; - BUG(); - goto out; - } - memcpy(mount_crypt_stat->global_default_cipher_name, - ECRYPTFS_DEFAULT_CIPHER, cipher_name_len); - mount_crypt_stat->global_default_cipher_name[cipher_name_len] - = '\0'; + int cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER); + + BUG_ON(cipher_name_len >= ECRYPTFS_MAX_CIPHER_NAME_SIZE); + strcpy(mount_crypt_stat->global_default_cipher_name, + ECRYPTFS_DEFAULT_CIPHER); } - if (!cipher_key_bytes_set) { + if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) + && !fn_cipher_name_set) + strcpy(mount_crypt_stat->global_default_fn_cipher_name, + mount_crypt_stat->global_default_cipher_name); + if (!cipher_key_bytes_set) mount_crypt_stat->global_default_cipher_key_size = 0; - } - rc = ecryptfs_process_cipher( - &mount_crypt_stat->global_key_tfm, + if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) + && !fn_cipher_key_bytes_set) + mount_crypt_stat->global_default_fn_cipher_key_bytes = + mount_crypt_stat->global_default_cipher_key_size; + + cipher_code = ecryptfs_code_for_cipher_string( mount_crypt_stat->global_default_cipher_name, - &mount_crypt_stat->global_default_cipher_key_size); - if (rc) { - printk(KERN_ERR "Error attempting to initialize cipher [%s] " - "with key size [%Zd] bytes; rc = [%d]\n", - mount_crypt_stat->global_default_cipher_name, - mount_crypt_stat->global_default_cipher_key_size, rc); - mount_crypt_stat->global_key_tfm = NULL; - mount_crypt_stat->global_auth_tok_key = NULL; - rc = -EINVAL; - goto out; - } - mutex_init(&mount_crypt_stat->global_key_tfm_mutex); - ecryptfs_printk(KERN_DEBUG, "Requesting the key with description: " - "[%s]\n", mount_crypt_stat->global_auth_tok_sig); - /* The reference to this key is held until umount is done The - * call to key_put is done in ecryptfs_put_super() */ - auth_tok_key = request_key(&key_type_user, - mount_crypt_stat->global_auth_tok_sig, - NULL); - if (!auth_tok_key || IS_ERR(auth_tok_key)) { - ecryptfs_printk(KERN_ERR, "Could not find key with " - "description: [%s]\n", - mount_crypt_stat->global_auth_tok_sig); - process_request_key_err(PTR_ERR(auth_tok_key)); + mount_crypt_stat->global_default_cipher_key_size); + if (!cipher_code) { + ecryptfs_printk(KERN_ERR, + "eCryptfs doesn't support cipher: %s", + mount_crypt_stat->global_default_cipher_name); rc = -EINVAL; goto out; } - auth_tok = ecryptfs_get_key_payload_data(auth_tok_key); - if (ecryptfs_verify_version(auth_tok->version)) { - ecryptfs_printk(KERN_ERR, "Data structure version mismatch. " - "Userspace tools must match eCryptfs kernel " - "module with major version [%d] and minor " - "version [%d]\n", ECRYPTFS_VERSION_MAJOR, - ECRYPTFS_VERSION_MINOR); - rc = -EINVAL; - goto out; + + mutex_lock(&key_tfm_list_mutex); + if (!ecryptfs_tfm_exists(mount_crypt_stat->global_default_cipher_name, + NULL)) { + rc = ecryptfs_add_new_key_tfm( + NULL, mount_crypt_stat->global_default_cipher_name, + mount_crypt_stat->global_default_cipher_key_size); + if (rc) { + printk(KERN_ERR "Error attempting to initialize " + "cipher with name = [%s] and key size = [%td]; " + "rc = [%d]\n", + mount_crypt_stat->global_default_cipher_name, + mount_crypt_stat->global_default_cipher_key_size, + rc); + rc = -EINVAL; + mutex_unlock(&key_tfm_list_mutex); + goto out; + } } - if (auth_tok->token_type != ECRYPTFS_PASSWORD - && auth_tok->token_type != ECRYPTFS_PRIVATE_KEY) { - ecryptfs_printk(KERN_ERR, "Invalid auth_tok structure " - "returned from key query\n"); - rc = -EINVAL; - goto out; + if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) + && !ecryptfs_tfm_exists( + mount_crypt_stat->global_default_fn_cipher_name, NULL)) { + rc = ecryptfs_add_new_key_tfm( + NULL, mount_crypt_stat->global_default_fn_cipher_name, + mount_crypt_stat->global_default_fn_cipher_key_bytes); + if (rc) { + printk(KERN_ERR "Error attempting to initialize " + "cipher with name = [%s] and key size = [%td]; " + "rc = [%d]\n", + mount_crypt_stat->global_default_fn_cipher_name, + mount_crypt_stat->global_default_fn_cipher_key_bytes, + rc); + rc = -EINVAL; + mutex_unlock(&key_tfm_list_mutex); + goto out; + } } - mount_crypt_stat->global_auth_tok_key = auth_tok_key; - mount_crypt_stat->global_auth_tok = auth_tok; + mutex_unlock(&key_tfm_list_mutex); + rc = ecryptfs_init_global_auth_toks(mount_crypt_stat); + if (rc) + printk(KERN_WARNING "One or more global auth toks could not " + "properly register; rc = [%d]\n", rc); out: return rc; } struct kmem_cache *ecryptfs_sb_info_cache; +static struct file_system_type ecryptfs_fs_type; /** - * ecryptfs_fill_super - * @sb: The ecryptfs super block - * @raw_data: The options passed to mount - * @silent: Not used but required by function prototype - * - * Sets up what we can of the sb, rest is done in ecryptfs_read_super - * - * Returns zero on success; non-zero otherwise + * ecryptfs_get_sb + * @fs_type + * @flags + * @dev_name: The path to mount over + * @raw_data: The options passed into the kernel */ -static int -ecryptfs_fill_super(struct super_block *sb, void *raw_data, int silent) +static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags, + const char *dev_name, void *raw_data) { - int rc = 0; + struct super_block *s; + struct ecryptfs_sb_info *sbi; + struct ecryptfs_dentry_info *root_info; + const char *err = "Getting sb failed"; + struct inode *inode; + struct path path; + uid_t check_ruid; + int rc; - /* Released in ecryptfs_put_super() */ - ecryptfs_set_superblock_private(sb, - kmem_cache_zalloc(ecryptfs_sb_info_cache, - GFP_KERNEL)); - if (!ecryptfs_superblock_to_private(sb)) { - ecryptfs_printk(KERN_WARNING, "Out of memory\n"); + sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL); + if (!sbi) { rc = -ENOMEM; goto out; } - sb->s_op = &ecryptfs_sops; - /* Released through deactivate_super(sb) from get_sb_nodev */ - sb->s_root = d_alloc(NULL, &(const struct qstr) { - .hash = 0,.name = "/",.len = 1}); - if (!sb->s_root) { - ecryptfs_printk(KERN_ERR, "d_alloc failed\n"); - rc = -ENOMEM; + + rc = ecryptfs_parse_options(sbi, raw_data, &check_ruid); + if (rc) { + err = "Error parsing options"; goto out; } - sb->s_root->d_op = &ecryptfs_dops; - sb->s_root->d_sb = sb; - sb->s_root->d_parent = sb->s_root; - /* Released in d_release when dput(sb->s_root) is called */ - /* through deactivate_super(sb) from get_sb_nodev() */ - ecryptfs_set_dentry_private(sb->s_root, - kmem_cache_zalloc(ecryptfs_dentry_info_cache, - GFP_KERNEL)); - if (!ecryptfs_dentry_to_private(sb->s_root)) { - ecryptfs_printk(KERN_ERR, - "dentry_info_cache alloc failed\n"); - rc = -ENOMEM; + + s = sget(fs_type, NULL, set_anon_super, flags, NULL); + if (IS_ERR(s)) { + rc = PTR_ERR(s); goto out; } - rc = 0; -out: - /* Should be able to rely on deactivate_super called from - * get_sb_nodev */ - return rc; -} -/** - * ecryptfs_read_super - * @sb: The ecryptfs super block - * @dev_name: The path to mount over - * - * Read the super block of the lower filesystem, and use - * ecryptfs_interpose to create our initial inode and super block - * struct. - */ -static int ecryptfs_read_super(struct super_block *sb, const char *dev_name) -{ - int rc; - struct nameidata nd; - struct dentry *lower_root; - struct vfsmount *lower_mnt; + rc = bdi_setup_and_register(&sbi->bdi, "ecryptfs", BDI_CAP_MAP_COPY); + if (rc) + goto out1; - memset(&nd, 0, sizeof(struct nameidata)); - rc = path_lookup(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &nd); + ecryptfs_set_superblock_private(s, sbi); + s->s_bdi = &sbi->bdi; + + /* ->kill_sb() will take care of sbi after that point */ + sbi = NULL; + s->s_op = &ecryptfs_sops; + s->s_d_op = &ecryptfs_dops; + + err = "Reading sb failed"; + rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path); if (rc) { - ecryptfs_printk(KERN_WARNING, "path_lookup() failed\n"); - goto out; + ecryptfs_printk(KERN_WARNING, "kern_path() failed\n"); + goto out1; } - lower_root = nd.dentry; - lower_mnt = nd.mnt; - ecryptfs_set_superblock_lower(sb, lower_root->d_sb); - sb->s_maxbytes = lower_root->d_sb->s_maxbytes; - ecryptfs_set_dentry_lower(sb->s_root, lower_root); - ecryptfs_set_dentry_lower_mnt(sb->s_root, lower_mnt); - if ((rc = ecryptfs_interpose(lower_root, sb->s_root, sb, 0))) + if (path.dentry->d_sb->s_type == &ecryptfs_fs_type) { + rc = -EINVAL; + printk(KERN_ERR "Mount on filesystem of type " + "eCryptfs explicitly disallowed due to " + "known incompatibilities\n"); goto out_free; - rc = 0; - goto out; -out_free: - path_release(&nd); -out: - return rc; -} - -/** - * ecryptfs_get_sb - * @fs_type - * @flags - * @dev_name: The path to mount over - * @raw_data: The options passed into the kernel - * - * The whole ecryptfs_get_sb process is broken into 4 functions: - * ecryptfs_parse_options(): handle options passed to ecryptfs, if any - * ecryptfs_fill_super(): used by get_sb_nodev, fills out the super_block - * with as much information as it can before needing - * the lower filesystem. - * ecryptfs_read_super(): this accesses the lower filesystem and uses - * ecryptfs_interpolate to perform most of the linking - * ecryptfs_interpolate(): links the lower filesystem into ecryptfs - */ -static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, - const char *dev_name, void *raw_data, - struct vfsmount *mnt) -{ - int rc; - struct super_block *sb; - - rc = get_sb_nodev(fs_type, flags, raw_data, ecryptfs_fill_super, mnt); - if (rc < 0) { - printk(KERN_ERR "Getting sb failed; rc = [%d]\n", rc); - goto out; } - sb = mnt->mnt_sb; - rc = ecryptfs_parse_options(sb, raw_data); - if (rc) { - printk(KERN_ERR "Error parsing options; rc = [%d]\n", rc); - goto out_abort; + + if (check_ruid && !uid_eq(path.dentry->d_inode->i_uid, current_uid())) { + rc = -EPERM; + printk(KERN_ERR "Mount of device (uid: %d) not owned by " + "requested user (uid: %d)\n", + i_uid_read(path.dentry->d_inode), + from_kuid(&init_user_ns, current_uid())); + goto out_free; } - rc = ecryptfs_read_super(sb, dev_name); - if (rc) { - printk(KERN_ERR "Reading sb failed; rc = [%d]\n", rc); - goto out_abort; + + ecryptfs_set_superblock_lower(s, path.dentry->d_sb); + + /** + * Set the POSIX ACL flag based on whether they're enabled in the lower + * mount. Force a read-only eCryptfs mount if the lower mount is ro. + * Allow a ro eCryptfs mount even when the lower mount is rw. + */ + s->s_flags = flags & ~MS_POSIXACL; + s->s_flags |= path.dentry->d_sb->s_flags & (MS_RDONLY | MS_POSIXACL); + + s->s_maxbytes = path.dentry->d_sb->s_maxbytes; + s->s_blocksize = path.dentry->d_sb->s_blocksize; + s->s_magic = ECRYPTFS_SUPER_MAGIC; + + inode = ecryptfs_get_inode(path.dentry->d_inode, s); + rc = PTR_ERR(inode); + if (IS_ERR(inode)) + goto out_free; + + s->s_root = d_make_root(inode); + if (!s->s_root) { + rc = -ENOMEM; + goto out_free; } - goto out; -out_abort: - dput(sb->s_root); - up_write(&sb->s_umount); - deactivate_super(sb); + + rc = -ENOMEM; + root_info = kmem_cache_zalloc(ecryptfs_dentry_info_cache, GFP_KERNEL); + if (!root_info) + goto out_free; + + /* ->kill_sb() will take care of root_info */ + ecryptfs_set_dentry_private(s->s_root, root_info); + root_info->lower_path = path; + + s->s_flags |= MS_ACTIVE; + return dget(s->s_root); + +out_free: + path_put(&path); +out1: + deactivate_locked_super(s); out: - return rc; + if (sbi) { + ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat); + kmem_cache_free(ecryptfs_sb_info_cache, sbi); + } + printk(KERN_ERR "%s; rc = [%d]\n", err, rc); + return ERR_PTR(rc); } /** @@ -558,20 +608,26 @@ out: * @sb: The ecryptfs super block * * Used to bring the superblock down and free the private data. - * Private data is free'd in ecryptfs_put_super() */ static void ecryptfs_kill_block_super(struct super_block *sb) { - generic_shutdown_super(sb); + struct ecryptfs_sb_info *sb_info = ecryptfs_superblock_to_private(sb); + kill_anon_super(sb); + if (!sb_info) + return; + ecryptfs_destroy_mount_crypt_stat(&sb_info->mount_crypt_stat); + bdi_destroy(&sb_info->bdi); + kmem_cache_free(ecryptfs_sb_info_cache, sb_info); } static struct file_system_type ecryptfs_fs_type = { .owner = THIS_MODULE, .name = "ecryptfs", - .get_sb = ecryptfs_get_sb, + .mount = ecryptfs_mount, .kill_sb = ecryptfs_kill_block_super, .fs_flags = 0 }; +MODULE_ALIAS_FS("ecryptfs"); /** * inode_info_init_once @@ -579,7 +635,7 @@ static struct file_system_type ecryptfs_fs_type = { * Initializes the ecryptfs_inode_info_cache when it is created */ static void -inode_info_init_once(void *vptr, struct kmem_cache *cachep, unsigned long flags) +inode_info_init_once(void *vptr) { struct ecryptfs_inode_info *ei = (struct ecryptfs_inode_info *)vptr; @@ -590,7 +646,7 @@ static struct ecryptfs_cache_info { struct kmem_cache **cache; const char *name; size_t size; - void (*ctor)(void*, struct kmem_cache *, unsigned long); + void (*ctor)(void *obj); } ecryptfs_cache_infos[] = { { .cache = &ecryptfs_auth_tok_list_item_cache, @@ -619,34 +675,34 @@ static struct ecryptfs_cache_info { .size = sizeof(struct ecryptfs_sb_info), }, { - .cache = &ecryptfs_header_cache_0, - .name = "ecryptfs_headers_0", + .cache = &ecryptfs_header_cache, + .name = "ecryptfs_headers", .size = PAGE_CACHE_SIZE, }, { - .cache = &ecryptfs_header_cache_1, - .name = "ecryptfs_headers_1", + .cache = &ecryptfs_xattr_cache, + .name = "ecryptfs_xattr_cache", .size = PAGE_CACHE_SIZE, }, { - .cache = &ecryptfs_header_cache_2, - .name = "ecryptfs_headers_2", - .size = PAGE_CACHE_SIZE, + .cache = &ecryptfs_key_record_cache, + .name = "ecryptfs_key_record_cache", + .size = sizeof(struct ecryptfs_key_record), }, { - .cache = &ecryptfs_xattr_cache, - .name = "ecryptfs_xattr_cache", - .size = PAGE_CACHE_SIZE, + .cache = &ecryptfs_key_sig_cache, + .name = "ecryptfs_key_sig_cache", + .size = sizeof(struct ecryptfs_key_sig), }, { - .cache = &ecryptfs_lower_page_cache, - .name = "ecryptfs_lower_page_cache", - .size = PAGE_CACHE_SIZE, + .cache = &ecryptfs_global_auth_tok_cache, + .name = "ecryptfs_global_auth_tok_cache", + .size = sizeof(struct ecryptfs_global_auth_tok), }, { - .cache = &ecryptfs_key_record_cache, - .name = "ecryptfs_key_record_cache", - .size = sizeof(struct ecryptfs_key_record), + .cache = &ecryptfs_key_tfm_cache, + .name = "ecryptfs_key_tfm_cache", + .size = sizeof(struct ecryptfs_key_tfm), }, }; @@ -654,6 +710,12 @@ static void ecryptfs_free_kmem_caches(void) { int i; + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) { struct ecryptfs_cache_info *info; @@ -689,125 +751,40 @@ static int ecryptfs_init_kmem_caches(void) return 0; } -struct ecryptfs_obj { - char *name; - struct list_head slot_list; - struct kobject kobj; -}; - -struct ecryptfs_attribute { - struct attribute attr; - ssize_t(*show) (struct ecryptfs_obj *, char *); - ssize_t(*store) (struct ecryptfs_obj *, const char *, size_t); -}; +static struct kobject *ecryptfs_kobj; -static ssize_t -ecryptfs_attr_store(struct kobject *kobj, - struct attribute *attr, const char *buf, size_t len) +static ssize_t version_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buff) { - struct ecryptfs_obj *obj = container_of(kobj, struct ecryptfs_obj, - kobj); - struct ecryptfs_attribute *attribute = - container_of(attr, struct ecryptfs_attribute, attr); - - return (attribute->store ? attribute->store(obj, buf, len) : 0); -} - -static ssize_t -ecryptfs_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) -{ - struct ecryptfs_obj *obj = container_of(kobj, struct ecryptfs_obj, - kobj); - struct ecryptfs_attribute *attribute = - container_of(attr, struct ecryptfs_attribute, attr); - - return (attribute->show ? attribute->show(obj, buf) : 0); + return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK); } -static struct sysfs_ops ecryptfs_sysfs_ops = { - .show = ecryptfs_attr_show, - .store = ecryptfs_attr_store -}; +static struct kobj_attribute version_attr = __ATTR_RO(version); -static struct kobj_type ecryptfs_ktype = { - .sysfs_ops = &ecryptfs_sysfs_ops +static struct attribute *attributes[] = { + &version_attr.attr, + NULL, }; -static decl_subsys(ecryptfs, &ecryptfs_ktype, NULL); - -static ssize_t version_show(struct ecryptfs_obj *obj, char *buff) -{ - return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK); -} - -static struct ecryptfs_attribute sysfs_attr_version = __ATTR_RO(version); - -static struct ecryptfs_version_str_map_elem { - u32 flag; - char *str; -} ecryptfs_version_str_map[] = { - {ECRYPTFS_VERSIONING_PASSPHRASE, "passphrase"}, - {ECRYPTFS_VERSIONING_PUBKEY, "pubkey"}, - {ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH, "plaintext passthrough"}, - {ECRYPTFS_VERSIONING_POLICY, "policy"}, - {ECRYPTFS_VERSIONING_XATTR, "metadata in extended attribute"} +static struct attribute_group attr_group = { + .attrs = attributes, }; -static ssize_t version_str_show(struct ecryptfs_obj *obj, char *buff) -{ - int i; - int remaining = PAGE_SIZE; - int total_written = 0; - - buff[0] = '\0'; - for (i = 0; i < ARRAY_SIZE(ecryptfs_version_str_map); i++) { - int entry_size; - - if (!(ECRYPTFS_VERSIONING_MASK - & ecryptfs_version_str_map[i].flag)) - continue; - entry_size = strlen(ecryptfs_version_str_map[i].str); - if ((entry_size + 2) > remaining) - goto out; - memcpy(buff, ecryptfs_version_str_map[i].str, entry_size); - buff[entry_size++] = '\n'; - buff[entry_size] = '\0'; - buff += entry_size; - total_written += entry_size; - remaining -= entry_size; - } -out: - return total_written; -} - -static struct ecryptfs_attribute sysfs_attr_version_str = __ATTR_RO(version_str); - static int do_sysfs_registration(void) { int rc; - if ((rc = subsystem_register(&ecryptfs_subsys))) { - printk(KERN_ERR - "Unable to register ecryptfs sysfs subsystem\n"); - goto out; - } - rc = sysfs_create_file(&ecryptfs_subsys.kobj, - &sysfs_attr_version.attr); - if (rc) { - printk(KERN_ERR - "Unable to create ecryptfs version attribute\n"); - subsystem_unregister(&ecryptfs_subsys); + ecryptfs_kobj = kobject_create_and_add("ecryptfs", fs_kobj); + if (!ecryptfs_kobj) { + printk(KERN_ERR "Unable to create ecryptfs kset\n"); + rc = -ENOMEM; goto out; } - rc = sysfs_create_file(&ecryptfs_subsys.kobj, - &sysfs_attr_version_str.attr); + rc = sysfs_create_group(ecryptfs_kobj, &attr_group); if (rc) { printk(KERN_ERR - "Unable to create ecryptfs version_str attribute\n"); - sysfs_remove_file(&ecryptfs_subsys.kobj, - &sysfs_attr_version.attr); - subsystem_unregister(&ecryptfs_subsys); - goto out; + "Unable to create ecryptfs version attributes\n"); + kobject_put(ecryptfs_kobj); } out: return rc; @@ -815,11 +792,8 @@ out: static void do_sysfs_unregistration(void) { - sysfs_remove_file(&ecryptfs_subsys.kobj, - &sysfs_attr_version.attr); - sysfs_remove_file(&ecryptfs_subsys.kobj, - &sysfs_attr_version_str.attr); - subsystem_unregister(&ecryptfs_subsys); + sysfs_remove_group(ecryptfs_kobj, &attr_group); + kobject_put(ecryptfs_kobj); } static int __init ecryptfs_init(void) @@ -831,9 +805,10 @@ static int __init ecryptfs_init(void) ecryptfs_printk(KERN_ERR, "The eCryptfs extent size is " "larger than the host's page size, and so " "eCryptfs cannot run on this system. The " - "default eCryptfs extent size is [%d] bytes; " - "the page size is [%d] bytes.\n", - ECRYPTFS_DEFAULT_EXTENT_SIZE, PAGE_CACHE_SIZE); + "default eCryptfs extent size is [%u] bytes; " + "the page size is [%lu] bytes.\n", + ECRYPTFS_DEFAULT_EXTENT_SIZE, + (unsigned long)PAGE_CACHE_SIZE); goto out; } rc = ecryptfs_init_kmem_caches(); @@ -842,36 +817,65 @@ static int __init ecryptfs_init(void) "Failed to allocate one or more kmem_cache objects\n"); goto out; } - rc = register_filesystem(&ecryptfs_fs_type); - if (rc) { - printk(KERN_ERR "Failed to register filesystem\n"); - ecryptfs_free_kmem_caches(); - goto out; - } - kobj_set_kset_s(&ecryptfs_subsys, fs_subsys); rc = do_sysfs_registration(); if (rc) { printk(KERN_ERR "sysfs registration failed\n"); - unregister_filesystem(&ecryptfs_fs_type); - ecryptfs_free_kmem_caches(); - goto out; + goto out_free_kmem_caches; + } + rc = ecryptfs_init_kthread(); + if (rc) { + printk(KERN_ERR "%s: kthread initialization failed; " + "rc = [%d]\n", __func__, rc); + goto out_do_sysfs_unregistration; + } + rc = ecryptfs_init_messaging(); + if (rc) { + printk(KERN_ERR "Failure occurred while attempting to " + "initialize the communications channel to " + "ecryptfsd\n"); + goto out_destroy_kthread; } - rc = ecryptfs_init_messaging(ecryptfs_transport); + rc = ecryptfs_init_crypto(); if (rc) { - ecryptfs_printk(KERN_ERR, "Failure occured while attempting to " - "initialize the eCryptfs netlink socket\n"); - do_sysfs_unregistration(); - unregister_filesystem(&ecryptfs_fs_type); - ecryptfs_free_kmem_caches(); + printk(KERN_ERR "Failure whilst attempting to init crypto; " + "rc = [%d]\n", rc); + goto out_release_messaging; + } + rc = register_filesystem(&ecryptfs_fs_type); + if (rc) { + printk(KERN_ERR "Failed to register filesystem\n"); + goto out_destroy_crypto; } + if (ecryptfs_verbosity > 0) + printk(KERN_CRIT "eCryptfs verbosity set to %d. Secret values " + "will be written to the syslog!\n", ecryptfs_verbosity); + + goto out; +out_destroy_crypto: + ecryptfs_destroy_crypto(); +out_release_messaging: + ecryptfs_release_messaging(); +out_destroy_kthread: + ecryptfs_destroy_kthread(); +out_do_sysfs_unregistration: + do_sysfs_unregistration(); +out_free_kmem_caches: + ecryptfs_free_kmem_caches(); out: return rc; } static void __exit ecryptfs_exit(void) { + int rc; + + rc = ecryptfs_destroy_crypto(); + if (rc) + printk(KERN_ERR "Failure whilst attempting to destroy crypto; " + "rc = [%d]\n", rc); + ecryptfs_release_messaging(); + ecryptfs_destroy_kthread(); do_sysfs_unregistration(); - ecryptfs_release_messaging(ecryptfs_transport); unregister_filesystem(&ecryptfs_fs_type); ecryptfs_free_kmem_caches(); } |
