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![Christoph Hellwig](/assets/img/avatar_default.png)
Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
906 lines
25 KiB
C
906 lines
25 KiB
C
/**
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* eCryptfs: Linux filesystem encryption layer
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*
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* Copyright (C) 1997-2003 Erez Zadok
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* Copyright (C) 2001-2003 Stony Brook University
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* Copyright (C) 2004-2007 International Business Machines Corp.
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* Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
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* Michael C. Thompson <mcthomps@us.ibm.com>
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* Tyler Hicks <tyhicks@ou.edu>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of the
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* License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
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* 02111-1307, USA.
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*/
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/module.h>
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#include <linux/namei.h>
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#include <linux/skbuff.h>
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#include <linux/crypto.h>
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#include <linux/mount.h>
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#include <linux/pagemap.h>
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#include <linux/key.h>
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#include <linux/parser.h>
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#include <linux/fs_stack.h>
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#include <linux/slab.h>
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#include <linux/magic.h>
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#include "ecryptfs_kernel.h"
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/**
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* Module parameter that defines the ecryptfs_verbosity level.
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*/
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int ecryptfs_verbosity = 0;
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module_param(ecryptfs_verbosity, int, 0);
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MODULE_PARM_DESC(ecryptfs_verbosity,
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"Initial verbosity level (0 or 1; defaults to "
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"0, which is Quiet)");
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/**
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* Module parameter that defines the number of message buffer elements
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*/
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unsigned int ecryptfs_message_buf_len = ECRYPTFS_DEFAULT_MSG_CTX_ELEMS;
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module_param(ecryptfs_message_buf_len, uint, 0);
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MODULE_PARM_DESC(ecryptfs_message_buf_len,
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"Number of message buffer elements");
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/**
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* Module parameter that defines the maximum guaranteed amount of time to wait
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* for a response from ecryptfsd. The actual sleep time will be, more than
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* likely, a small amount greater than this specified value, but only less if
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* the message successfully arrives.
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*/
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signed long ecryptfs_message_wait_timeout = ECRYPTFS_MAX_MSG_CTX_TTL / HZ;
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module_param(ecryptfs_message_wait_timeout, long, 0);
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MODULE_PARM_DESC(ecryptfs_message_wait_timeout,
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"Maximum number of seconds that an operation will "
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"sleep while waiting for a message response from "
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"userspace");
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/**
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* Module parameter that is an estimate of the maximum number of users
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* that will be concurrently using eCryptfs. Set this to the right
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* value to balance performance and memory use.
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*/
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unsigned int ecryptfs_number_of_users = ECRYPTFS_DEFAULT_NUM_USERS;
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module_param(ecryptfs_number_of_users, uint, 0);
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MODULE_PARM_DESC(ecryptfs_number_of_users, "An estimate of the number of "
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"concurrent users of eCryptfs");
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void __ecryptfs_printk(const char *fmt, ...)
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{
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va_list args;
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va_start(args, fmt);
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if (fmt[1] == '7') { /* KERN_DEBUG */
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if (ecryptfs_verbosity >= 1)
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vprintk(fmt, args);
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} else
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vprintk(fmt, args);
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va_end(args);
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}
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/**
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* ecryptfs_init_lower_file
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* @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with
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* the lower dentry and the lower mount set
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*
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* eCryptfs only ever keeps a single open file for every lower
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* inode. All I/O operations to the lower inode occur through that
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* file. When the first eCryptfs dentry that interposes with the first
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* lower dentry for that inode is created, this function creates the
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* lower file struct and associates it with the eCryptfs
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* inode. When all eCryptfs files associated with the inode are released, the
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* file is closed.
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*
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* The lower file will be opened with read/write permissions, if
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* possible. Otherwise, it is opened read-only.
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*
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* This function does nothing if a lower file is already
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* associated with the eCryptfs inode.
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*
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* Returns zero on success; non-zero otherwise
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*/
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static int ecryptfs_init_lower_file(struct dentry *dentry,
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struct file **lower_file)
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{
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const struct cred *cred = current_cred();
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struct path *path = ecryptfs_dentry_to_lower_path(dentry);
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int rc;
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rc = ecryptfs_privileged_open(lower_file, path->dentry, path->mnt,
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cred);
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if (rc) {
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printk(KERN_ERR "Error opening lower file "
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"for lower_dentry [0x%p] and lower_mnt [0x%p]; "
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"rc = [%d]\n", path->dentry, path->mnt, rc);
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(*lower_file) = NULL;
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}
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return rc;
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}
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int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode)
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{
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struct ecryptfs_inode_info *inode_info;
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int count, rc = 0;
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inode_info = ecryptfs_inode_to_private(inode);
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mutex_lock(&inode_info->lower_file_mutex);
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count = atomic_inc_return(&inode_info->lower_file_count);
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if (WARN_ON_ONCE(count < 1))
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rc = -EINVAL;
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else if (count == 1) {
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rc = ecryptfs_init_lower_file(dentry,
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&inode_info->lower_file);
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if (rc)
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atomic_set(&inode_info->lower_file_count, 0);
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}
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mutex_unlock(&inode_info->lower_file_mutex);
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return rc;
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}
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void ecryptfs_put_lower_file(struct inode *inode)
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{
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struct ecryptfs_inode_info *inode_info;
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inode_info = ecryptfs_inode_to_private(inode);
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if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count,
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&inode_info->lower_file_mutex)) {
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filemap_write_and_wait(inode->i_mapping);
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fput(inode_info->lower_file);
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inode_info->lower_file = NULL;
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mutex_unlock(&inode_info->lower_file_mutex);
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}
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}
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enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig,
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ecryptfs_opt_cipher, ecryptfs_opt_ecryptfs_cipher,
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ecryptfs_opt_ecryptfs_key_bytes,
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ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata,
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ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig,
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ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes,
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ecryptfs_opt_unlink_sigs, ecryptfs_opt_mount_auth_tok_only,
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ecryptfs_opt_check_dev_ruid,
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ecryptfs_opt_err };
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static const match_table_t tokens = {
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{ecryptfs_opt_sig, "sig=%s"},
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{ecryptfs_opt_ecryptfs_sig, "ecryptfs_sig=%s"},
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{ecryptfs_opt_cipher, "cipher=%s"},
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{ecryptfs_opt_ecryptfs_cipher, "ecryptfs_cipher=%s"},
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{ecryptfs_opt_ecryptfs_key_bytes, "ecryptfs_key_bytes=%u"},
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{ecryptfs_opt_passthrough, "ecryptfs_passthrough"},
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{ecryptfs_opt_xattr_metadata, "ecryptfs_xattr_metadata"},
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{ecryptfs_opt_encrypted_view, "ecryptfs_encrypted_view"},
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{ecryptfs_opt_fnek_sig, "ecryptfs_fnek_sig=%s"},
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{ecryptfs_opt_fn_cipher, "ecryptfs_fn_cipher=%s"},
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{ecryptfs_opt_fn_cipher_key_bytes, "ecryptfs_fn_key_bytes=%u"},
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{ecryptfs_opt_unlink_sigs, "ecryptfs_unlink_sigs"},
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{ecryptfs_opt_mount_auth_tok_only, "ecryptfs_mount_auth_tok_only"},
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{ecryptfs_opt_check_dev_ruid, "ecryptfs_check_dev_ruid"},
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{ecryptfs_opt_err, NULL}
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};
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static int ecryptfs_init_global_auth_toks(
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struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
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{
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struct ecryptfs_global_auth_tok *global_auth_tok;
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struct ecryptfs_auth_tok *auth_tok;
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int rc = 0;
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list_for_each_entry(global_auth_tok,
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&mount_crypt_stat->global_auth_tok_list,
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mount_crypt_stat_list) {
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rc = ecryptfs_keyring_auth_tok_for_sig(
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&global_auth_tok->global_auth_tok_key, &auth_tok,
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global_auth_tok->sig);
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if (rc) {
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printk(KERN_ERR "Could not find valid key in user "
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"session keyring for sig specified in mount "
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"option: [%s]\n", global_auth_tok->sig);
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global_auth_tok->flags |= ECRYPTFS_AUTH_TOK_INVALID;
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goto out;
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} else {
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global_auth_tok->flags &= ~ECRYPTFS_AUTH_TOK_INVALID;
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up_write(&(global_auth_tok->global_auth_tok_key)->sem);
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}
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}
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out:
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return rc;
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}
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static void ecryptfs_init_mount_crypt_stat(
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struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
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{
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memset((void *)mount_crypt_stat, 0,
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sizeof(struct ecryptfs_mount_crypt_stat));
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INIT_LIST_HEAD(&mount_crypt_stat->global_auth_tok_list);
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mutex_init(&mount_crypt_stat->global_auth_tok_list_mutex);
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mount_crypt_stat->flags |= ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED;
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}
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/**
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* ecryptfs_parse_options
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* @sb: The ecryptfs super block
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* @options: The options passed to the kernel
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* @check_ruid: set to 1 if device uid should be checked against the ruid
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*
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* Parse mount options:
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* debug=N - ecryptfs_verbosity level for debug output
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* sig=XXX - description(signature) of the key to use
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*
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* Returns the dentry object of the lower-level (lower/interposed)
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* directory; We want to mount our stackable file system on top of
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* that lower directory.
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*
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* The signature of the key to use must be the description of a key
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* already in the keyring. Mounting will fail if the key can not be
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* found.
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*
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* Returns zero on success; non-zero on error
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*/
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static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options,
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uid_t *check_ruid)
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{
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char *p;
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int rc = 0;
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int sig_set = 0;
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int cipher_name_set = 0;
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int fn_cipher_name_set = 0;
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int cipher_key_bytes;
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int cipher_key_bytes_set = 0;
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int fn_cipher_key_bytes;
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int fn_cipher_key_bytes_set = 0;
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struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
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&sbi->mount_crypt_stat;
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substring_t args[MAX_OPT_ARGS];
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int token;
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char *sig_src;
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char *cipher_name_dst;
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char *cipher_name_src;
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char *fn_cipher_name_dst;
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char *fn_cipher_name_src;
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char *fnek_dst;
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char *fnek_src;
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char *cipher_key_bytes_src;
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char *fn_cipher_key_bytes_src;
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u8 cipher_code;
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*check_ruid = 0;
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if (!options) {
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rc = -EINVAL;
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goto out;
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}
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ecryptfs_init_mount_crypt_stat(mount_crypt_stat);
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while ((p = strsep(&options, ",")) != NULL) {
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if (!*p)
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continue;
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token = match_token(p, tokens, args);
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switch (token) {
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case ecryptfs_opt_sig:
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case ecryptfs_opt_ecryptfs_sig:
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sig_src = args[0].from;
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rc = ecryptfs_add_global_auth_tok(mount_crypt_stat,
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sig_src, 0);
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if (rc) {
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printk(KERN_ERR "Error attempting to register "
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"global sig; rc = [%d]\n", rc);
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goto out;
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}
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sig_set = 1;
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break;
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case ecryptfs_opt_cipher:
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case ecryptfs_opt_ecryptfs_cipher:
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cipher_name_src = args[0].from;
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cipher_name_dst =
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mount_crypt_stat->
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global_default_cipher_name;
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strncpy(cipher_name_dst, cipher_name_src,
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ECRYPTFS_MAX_CIPHER_NAME_SIZE);
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cipher_name_dst[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
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cipher_name_set = 1;
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break;
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case ecryptfs_opt_ecryptfs_key_bytes:
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cipher_key_bytes_src = args[0].from;
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cipher_key_bytes =
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(int)simple_strtol(cipher_key_bytes_src,
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&cipher_key_bytes_src, 0);
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mount_crypt_stat->global_default_cipher_key_size =
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cipher_key_bytes;
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cipher_key_bytes_set = 1;
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break;
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case ecryptfs_opt_passthrough:
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mount_crypt_stat->flags |=
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ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED;
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break;
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case ecryptfs_opt_xattr_metadata:
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mount_crypt_stat->flags |=
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ECRYPTFS_XATTR_METADATA_ENABLED;
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break;
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case ecryptfs_opt_encrypted_view:
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mount_crypt_stat->flags |=
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ECRYPTFS_XATTR_METADATA_ENABLED;
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mount_crypt_stat->flags |=
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ECRYPTFS_ENCRYPTED_VIEW_ENABLED;
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break;
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case ecryptfs_opt_fnek_sig:
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fnek_src = args[0].from;
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fnek_dst =
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mount_crypt_stat->global_default_fnek_sig;
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strncpy(fnek_dst, fnek_src, ECRYPTFS_SIG_SIZE_HEX);
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mount_crypt_stat->global_default_fnek_sig[
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ECRYPTFS_SIG_SIZE_HEX] = '\0';
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rc = ecryptfs_add_global_auth_tok(
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mount_crypt_stat,
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mount_crypt_stat->global_default_fnek_sig,
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ECRYPTFS_AUTH_TOK_FNEK);
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if (rc) {
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printk(KERN_ERR "Error attempting to register "
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"global fnek sig [%s]; rc = [%d]\n",
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mount_crypt_stat->global_default_fnek_sig,
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rc);
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goto out;
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}
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mount_crypt_stat->flags |=
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(ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES
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| ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK);
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break;
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case ecryptfs_opt_fn_cipher:
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fn_cipher_name_src = args[0].from;
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fn_cipher_name_dst =
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mount_crypt_stat->global_default_fn_cipher_name;
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strncpy(fn_cipher_name_dst, fn_cipher_name_src,
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ECRYPTFS_MAX_CIPHER_NAME_SIZE);
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mount_crypt_stat->global_default_fn_cipher_name[
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ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
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fn_cipher_name_set = 1;
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break;
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case ecryptfs_opt_fn_cipher_key_bytes:
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fn_cipher_key_bytes_src = args[0].from;
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fn_cipher_key_bytes =
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(int)simple_strtol(fn_cipher_key_bytes_src,
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&fn_cipher_key_bytes_src, 0);
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mount_crypt_stat->global_default_fn_cipher_key_bytes =
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fn_cipher_key_bytes;
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fn_cipher_key_bytes_set = 1;
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break;
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case ecryptfs_opt_unlink_sigs:
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mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS;
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break;
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case ecryptfs_opt_mount_auth_tok_only:
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mount_crypt_stat->flags |=
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ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY;
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break;
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case ecryptfs_opt_check_dev_ruid:
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*check_ruid = 1;
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break;
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case ecryptfs_opt_err:
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default:
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printk(KERN_WARNING
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"%s: eCryptfs: unrecognized option [%s]\n",
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__func__, p);
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}
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}
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if (!sig_set) {
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rc = -EINVAL;
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ecryptfs_printk(KERN_ERR, "You must supply at least one valid "
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"auth tok signature as a mount "
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"parameter; see the eCryptfs README\n");
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goto out;
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}
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if (!cipher_name_set) {
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int cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER);
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BUG_ON(cipher_name_len >= ECRYPTFS_MAX_CIPHER_NAME_SIZE);
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strcpy(mount_crypt_stat->global_default_cipher_name,
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ECRYPTFS_DEFAULT_CIPHER);
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}
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if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
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&& !fn_cipher_name_set)
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strcpy(mount_crypt_stat->global_default_fn_cipher_name,
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mount_crypt_stat->global_default_cipher_name);
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if (!cipher_key_bytes_set)
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mount_crypt_stat->global_default_cipher_key_size = 0;
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if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
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&& !fn_cipher_key_bytes_set)
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mount_crypt_stat->global_default_fn_cipher_key_bytes =
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mount_crypt_stat->global_default_cipher_key_size;
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cipher_code = ecryptfs_code_for_cipher_string(
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mount_crypt_stat->global_default_cipher_name,
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mount_crypt_stat->global_default_cipher_key_size);
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if (!cipher_code) {
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ecryptfs_printk(KERN_ERR,
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"eCryptfs doesn't support cipher: %s",
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mount_crypt_stat->global_default_cipher_name);
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rc = -EINVAL;
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goto out;
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}
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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 ((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;
|
|
}
|
|
}
|
|
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_get_sb
|
|
* @fs_type
|
|
* @flags
|
|
* @dev_name: The path to mount over
|
|
* @raw_data: The options passed into the kernel
|
|
*/
|
|
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_mount_crypt_stat *mount_crypt_stat;
|
|
struct ecryptfs_dentry_info *root_info;
|
|
const char *err = "Getting sb failed";
|
|
struct inode *inode;
|
|
struct path path;
|
|
uid_t check_ruid;
|
|
int rc;
|
|
|
|
sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL);
|
|
if (!sbi) {
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
rc = ecryptfs_parse_options(sbi, raw_data, &check_ruid);
|
|
if (rc) {
|
|
err = "Error parsing options";
|
|
goto out;
|
|
}
|
|
mount_crypt_stat = &sbi->mount_crypt_stat;
|
|
|
|
s = sget(fs_type, NULL, set_anon_super, flags, NULL);
|
|
if (IS_ERR(s)) {
|
|
rc = PTR_ERR(s);
|
|
goto out;
|
|
}
|
|
|
|
rc = bdi_setup_and_register(&sbi->bdi, "ecryptfs");
|
|
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, "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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
ecryptfs_set_superblock_lower(s, path.dentry->d_sb);
|
|
|
|
/**
|
|
* Set the POSIX ACL flag based on whether they're enabled in the lower
|
|
* mount.
|
|
*/
|
|
s->s_flags = flags & ~MS_POSIXACL;
|
|
s->s_flags |= path.dentry->d_sb->s_flags & MS_POSIXACL;
|
|
|
|
/**
|
|
* Force a read-only eCryptfs mount when:
|
|
* 1) The lower mount is ro
|
|
* 2) The ecryptfs_encrypted_view mount option is specified
|
|
*/
|
|
if (path.dentry->d_sb->s_flags & MS_RDONLY ||
|
|
mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
|
|
s->s_flags |= MS_RDONLY;
|
|
|
|
s->s_maxbytes = path.dentry->d_sb->s_maxbytes;
|
|
s->s_blocksize = path.dentry->d_sb->s_blocksize;
|
|
s->s_magic = ECRYPTFS_SUPER_MAGIC;
|
|
s->s_stack_depth = path.dentry->d_sb->s_stack_depth + 1;
|
|
|
|
rc = -EINVAL;
|
|
if (s->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
|
|
pr_err("eCryptfs: maximum fs stacking depth exceeded\n");
|
|
goto out_free;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
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:
|
|
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);
|
|
}
|
|
|
|
/**
|
|
* ecryptfs_kill_block_super
|
|
* @sb: The ecryptfs super block
|
|
*
|
|
* Used to bring the superblock down and free the private data.
|
|
*/
|
|
static void ecryptfs_kill_block_super(struct super_block *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",
|
|
.mount = ecryptfs_mount,
|
|
.kill_sb = ecryptfs_kill_block_super,
|
|
.fs_flags = 0
|
|
};
|
|
MODULE_ALIAS_FS("ecryptfs");
|
|
|
|
/**
|
|
* inode_info_init_once
|
|
*
|
|
* Initializes the ecryptfs_inode_info_cache when it is created
|
|
*/
|
|
static void
|
|
inode_info_init_once(void *vptr)
|
|
{
|
|
struct ecryptfs_inode_info *ei = (struct ecryptfs_inode_info *)vptr;
|
|
|
|
inode_init_once(&ei->vfs_inode);
|
|
}
|
|
|
|
static struct ecryptfs_cache_info {
|
|
struct kmem_cache **cache;
|
|
const char *name;
|
|
size_t size;
|
|
void (*ctor)(void *obj);
|
|
} ecryptfs_cache_infos[] = {
|
|
{
|
|
.cache = &ecryptfs_auth_tok_list_item_cache,
|
|
.name = "ecryptfs_auth_tok_list_item",
|
|
.size = sizeof(struct ecryptfs_auth_tok_list_item),
|
|
},
|
|
{
|
|
.cache = &ecryptfs_file_info_cache,
|
|
.name = "ecryptfs_file_cache",
|
|
.size = sizeof(struct ecryptfs_file_info),
|
|
},
|
|
{
|
|
.cache = &ecryptfs_dentry_info_cache,
|
|
.name = "ecryptfs_dentry_info_cache",
|
|
.size = sizeof(struct ecryptfs_dentry_info),
|
|
},
|
|
{
|
|
.cache = &ecryptfs_inode_info_cache,
|
|
.name = "ecryptfs_inode_cache",
|
|
.size = sizeof(struct ecryptfs_inode_info),
|
|
.ctor = inode_info_init_once,
|
|
},
|
|
{
|
|
.cache = &ecryptfs_sb_info_cache,
|
|
.name = "ecryptfs_sb_cache",
|
|
.size = sizeof(struct ecryptfs_sb_info),
|
|
},
|
|
{
|
|
.cache = &ecryptfs_header_cache,
|
|
.name = "ecryptfs_headers",
|
|
.size = PAGE_CACHE_SIZE,
|
|
},
|
|
{
|
|
.cache = &ecryptfs_xattr_cache,
|
|
.name = "ecryptfs_xattr_cache",
|
|
.size = PAGE_CACHE_SIZE,
|
|
},
|
|
{
|
|
.cache = &ecryptfs_key_record_cache,
|
|
.name = "ecryptfs_key_record_cache",
|
|
.size = sizeof(struct ecryptfs_key_record),
|
|
},
|
|
{
|
|
.cache = &ecryptfs_key_sig_cache,
|
|
.name = "ecryptfs_key_sig_cache",
|
|
.size = sizeof(struct ecryptfs_key_sig),
|
|
},
|
|
{
|
|
.cache = &ecryptfs_global_auth_tok_cache,
|
|
.name = "ecryptfs_global_auth_tok_cache",
|
|
.size = sizeof(struct ecryptfs_global_auth_tok),
|
|
},
|
|
{
|
|
.cache = &ecryptfs_key_tfm_cache,
|
|
.name = "ecryptfs_key_tfm_cache",
|
|
.size = sizeof(struct ecryptfs_key_tfm),
|
|
},
|
|
};
|
|
|
|
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;
|
|
|
|
info = &ecryptfs_cache_infos[i];
|
|
if (*(info->cache))
|
|
kmem_cache_destroy(*(info->cache));
|
|
}
|
|
}
|
|
|
|
/**
|
|
* ecryptfs_init_kmem_caches
|
|
*
|
|
* Returns zero on success; non-zero otherwise
|
|
*/
|
|
static int ecryptfs_init_kmem_caches(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) {
|
|
struct ecryptfs_cache_info *info;
|
|
|
|
info = &ecryptfs_cache_infos[i];
|
|
*(info->cache) = kmem_cache_create(info->name, info->size,
|
|
0, SLAB_HWCACHE_ALIGN, info->ctor);
|
|
if (!*(info->cache)) {
|
|
ecryptfs_free_kmem_caches();
|
|
ecryptfs_printk(KERN_WARNING, "%s: "
|
|
"kmem_cache_create failed\n",
|
|
info->name);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct kobject *ecryptfs_kobj;
|
|
|
|
static ssize_t version_show(struct kobject *kobj,
|
|
struct kobj_attribute *attr, char *buff)
|
|
{
|
|
return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK);
|
|
}
|
|
|
|
static struct kobj_attribute version_attr = __ATTR_RO(version);
|
|
|
|
static struct attribute *attributes[] = {
|
|
&version_attr.attr,
|
|
NULL,
|
|
};
|
|
|
|
static struct attribute_group attr_group = {
|
|
.attrs = attributes,
|
|
};
|
|
|
|
static int do_sysfs_registration(void)
|
|
{
|
|
int rc;
|
|
|
|
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_group(ecryptfs_kobj, &attr_group);
|
|
if (rc) {
|
|
printk(KERN_ERR
|
|
"Unable to create ecryptfs version attributes\n");
|
|
kobject_put(ecryptfs_kobj);
|
|
}
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static void do_sysfs_unregistration(void)
|
|
{
|
|
sysfs_remove_group(ecryptfs_kobj, &attr_group);
|
|
kobject_put(ecryptfs_kobj);
|
|
}
|
|
|
|
static int __init ecryptfs_init(void)
|
|
{
|
|
int rc;
|
|
|
|
if (ECRYPTFS_DEFAULT_EXTENT_SIZE > PAGE_CACHE_SIZE) {
|
|
rc = -EINVAL;
|
|
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 [%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();
|
|
if (rc) {
|
|
printk(KERN_ERR
|
|
"Failed to allocate one or more kmem_cache objects\n");
|
|
goto out;
|
|
}
|
|
rc = do_sysfs_registration();
|
|
if (rc) {
|
|
printk(KERN_ERR "sysfs registration failed\n");
|
|
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_crypto();
|
|
if (rc) {
|
|
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();
|
|
unregister_filesystem(&ecryptfs_fs_type);
|
|
ecryptfs_free_kmem_caches();
|
|
}
|
|
|
|
MODULE_AUTHOR("Michael A. Halcrow <mhalcrow@us.ibm.com>");
|
|
MODULE_DESCRIPTION("eCryptfs");
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_init(ecryptfs_init)
|
|
module_exit(ecryptfs_exit)
|