diff options
Diffstat (limited to 'fs/ecryptfs/main.c')
-rw-r--r-- | fs/ecryptfs/main.c | 185 |
1 files changed, 86 insertions, 99 deletions
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index cbd4e18adb20..758323a0f09a 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -36,6 +36,7 @@ #include <linux/parser.h> #include <linux/fs_stack.h> #include <linux/slab.h> +#include <linux/magic.h> #include "ecryptfs_kernel.h" /** @@ -141,25 +142,12 @@ int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry) return rc; } -/** - * ecryptfs_interpose - * @lower_dentry: Existing dentry in the lower filesystem - * @dentry: ecryptfs' dentry - * @sb: ecryptfs's super_block - * @flags: flags to govern behavior of interpose procedure - * - * Interposes upper and lower dentries. - * - * Returns zero on success; non-zero otherwise - */ -int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry, - struct super_block *sb, u32 flags) +static struct inode *ecryptfs_get_inode(struct inode *lower_inode, + struct super_block *sb) { - struct inode *lower_inode; struct inode *inode; int rc = 0; - lower_inode = lower_dentry->d_inode; if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb)) { rc = -EXDEV; goto out; @@ -189,17 +177,38 @@ int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry, if (special_file(lower_inode->i_mode)) init_special_inode(inode, lower_inode->i_mode, lower_inode->i_rdev); - dentry->d_op = &ecryptfs_dops; fsstack_copy_attr_all(inode, lower_inode); /* This size will be overwritten for real files w/ headers and * other metadata */ fsstack_copy_inode_size(inode, lower_inode); + return inode; +out: + return ERR_PTR(rc); +} + +/** + * ecryptfs_interpose + * @lower_dentry: Existing dentry in the lower filesystem + * @dentry: ecryptfs' dentry + * @sb: ecryptfs's super_block + * @flags: flags to govern behavior of interpose procedure + * + * Interposes upper and lower dentries. + * + * Returns zero on success; non-zero otherwise + */ +int ecryptfs_interpose(struct dentry *lower_dentry, struct dentry *dentry, + struct super_block *sb, u32 flags) +{ + struct inode *lower_inode = lower_dentry->d_inode; + struct inode *inode = ecryptfs_get_inode(lower_inode, sb); + if (IS_ERR(inode)) + return PTR_ERR(inode); if (flags & ECRYPTFS_INTERPOSE_FLAG_D_ADD) d_add(dentry, inode); else d_instantiate(dentry, inode); -out: - return rc; + return 0; } enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig, @@ -208,7 +217,8 @@ enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig, ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata, ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig, ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes, - ecryptfs_opt_unlink_sigs, ecryptfs_opt_err }; + ecryptfs_opt_unlink_sigs, ecryptfs_opt_mount_auth_tok_only, + ecryptfs_opt_err }; static const match_table_t tokens = { {ecryptfs_opt_sig, "sig=%s"}, @@ -223,6 +233,7 @@ static const match_table_t tokens = { {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_err, NULL} }; @@ -406,6 +417,10 @@ static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options) 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_err: default: printk(KERN_WARNING @@ -486,68 +501,21 @@ struct kmem_cache *ecryptfs_sb_info_cache; static struct file_system_type ecryptfs_fs_type; /** - * 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) -{ - struct path path; - int rc; - - rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path); - if (rc) { - ecryptfs_printk(KERN_WARNING, "path_lookup() failed\n"); - goto out; - } - 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; - } - ecryptfs_set_superblock_lower(sb, path.dentry->d_sb); - sb->s_maxbytes = path.dentry->d_sb->s_maxbytes; - sb->s_blocksize = path.dentry->d_sb->s_blocksize; - ecryptfs_set_dentry_lower(sb->s_root, path.dentry); - ecryptfs_set_dentry_lower_mnt(sb->s_root, path.mnt); - rc = ecryptfs_interpose(path.dentry, sb->s_root, sb, 0); - if (rc) - goto out_free; - rc = 0; - goto out; -out_free: - path_put(&path); -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 3 functions: - * ecryptfs_parse_options(): handle options passed to ecryptfs, if any - * ecryptfs_read_super(): this accesses the lower filesystem and uses - * ecryptfs_interpose to perform most of the linking - * ecryptfs_interpose(): links the lower filesystem into ecryptfs (inode.c) */ -static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, - const char *dev_name, void *raw_data, - struct vfsmount *mnt) +static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags, + const char *dev_name, void *raw_data) { 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; int rc; sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL); @@ -570,10 +538,8 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, s->s_flags = flags; rc = bdi_setup_and_register(&sbi->bdi, "ecryptfs", BDI_CAP_MAP_COPY); - if (rc) { - deactivate_locked_super(s); - goto out; - } + if (rc) + goto out1; ecryptfs_set_superblock_private(s, sbi); s->s_bdi = &sbi->bdi; @@ -581,42 +547,62 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags, /* ->kill_sb() will take care of sbi after that point */ sbi = NULL; s->s_op = &ecryptfs_sops; + s->s_d_op = &ecryptfs_dops; - rc = -ENOMEM; - s->s_root = d_alloc(NULL, &(const struct qstr) { - .hash = 0,.name = "/",.len = 1}); + err = "Reading sb failed"; + rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path); + if (rc) { + ecryptfs_printk(KERN_WARNING, "kern_path() failed\n"); + goto out1; + } + 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; + } + ecryptfs_set_superblock_lower(s, path.dentry->d_sb); + 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_alloc_root(inode); if (!s->s_root) { - deactivate_locked_super(s); - goto out; + iput(inode); + rc = -ENOMEM; + goto out_free; } - s->s_root->d_op = &ecryptfs_dops; - s->s_root->d_sb = s; - s->s_root->d_parent = s->s_root; + rc = -ENOMEM; root_info = kmem_cache_zalloc(ecryptfs_dentry_info_cache, GFP_KERNEL); - if (!root_info) { - deactivate_locked_super(s); - goto out; - } + if (!root_info) + goto out_free; + /* ->kill_sb() will take care of root_info */ ecryptfs_set_dentry_private(s->s_root, root_info); + ecryptfs_set_dentry_lower(s->s_root, path.dentry); + ecryptfs_set_dentry_lower_mnt(s->s_root, path.mnt); + s->s_flags |= MS_ACTIVE; - rc = ecryptfs_read_super(s, dev_name); - if (rc) { - deactivate_locked_super(s); - err = "Reading sb failed"; - goto out; - } - simple_set_mnt(mnt, s); - return 0; + return dget(s->s_root); +out_free: + path_put(&path); +out1: + deactivate_locked_super(s); out: 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 rc; + return ERR_PTR(rc); } /** @@ -639,7 +625,7 @@ static void ecryptfs_kill_block_super(struct super_block *sb) 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 }; @@ -824,9 +810,10 @@ 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(); |