#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"
/**
lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
rc = ecryptfs_privileged_open(&inode_info->lower_file,
lower_dentry, lower_mnt, cred);
- if (rc || IS_ERR(inode_info->lower_file)) {
+ if (rc) {
printk(KERN_ERR "Error opening lower persistent file "
"for lower_dentry [0x%p] and lower_mnt [0x%p]; "
"rc = [%d]\n", lower_dentry, lower_mnt, rc);
- rc = PTR_ERR(inode_info->lower_file);
inode_info->lower_file = NULL;
}
}
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;
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, NULL);
+ 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,
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_mount_auth_tok_only,
+ ecryptfs_opt_check_dev_ruid,
ecryptfs_opt_err };
static const match_table_t tokens = {
{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_parse_options
* @sb: The ecryptfs super block
* @options: The options pased 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
*
* 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 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 *cipher_key_bytes_src;
char *fn_cipher_key_bytes_src;
+ *check_ruid = 0;
+
if (!options) {
rc = -EINVAL;
goto out;
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:
printk(KERN_WARNING
}
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, 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)
-{
- struct path path;
- int rc;
+ s->s_flags = flags;
+ rc = bdi_setup_and_register(&sbi->bdi, "ecryptfs", BDI_CAP_MAP_COPY);
+ if (rc)
+ goto out1;
+
+ 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;
}
- 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)
+ 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_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 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 && 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",
+ path.dentry->d_inode->i_uid, 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);
+ 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) {
+ iput(inode);
+ 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);
+ ecryptfs_set_dentry_lower(s->s_root, path.dentry);
+ ecryptfs_set_dentry_lower_mnt(s->s_root, path.mnt);
+
+ 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);
}
/**
* @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
};
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();
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