~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/ecryptfs/super.c

Version: ~ [ linux-5.4-rc7 ] ~ [ linux-5.3.11 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.84 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.154 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.201 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.201 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.77 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /**
  2  * eCryptfs: Linux filesystem encryption layer
  3  *
  4  * Copyright (C) 1997-2003 Erez Zadok
  5  * Copyright (C) 2001-2003 Stony Brook University
  6  * Copyright (C) 2004-2006 International Business Machines Corp.
  7  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
  8  *              Michael C. Thompson <mcthomps@us.ibm.com>
  9  *
 10  * This program is free software; you can redistribute it and/or
 11  * modify it under the terms of the GNU General Public License as
 12  * published by the Free Software Foundation; either version 2 of the
 13  * License, or (at your option) any later version.
 14  *
 15  * This program is distributed in the hope that it will be useful, but
 16  * WITHOUT ANY WARRANTY; without even the implied warranty of
 17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 18  * General Public License for more details.
 19  *
 20  * You should have received a copy of the GNU General Public License
 21  * along with this program; if not, write to the Free Software
 22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 23  * 02111-1307, USA.
 24  */
 25 
 26 #include <linux/fs.h>
 27 #include <linux/mount.h>
 28 #include <linux/key.h>
 29 #include <linux/slab.h>
 30 #include <linux/seq_file.h>
 31 #include <linux/file.h>
 32 #include <linux/statfs.h>
 33 #include <linux/magic.h>
 34 #include "ecryptfs_kernel.h"
 35 
 36 struct kmem_cache *ecryptfs_inode_info_cache;
 37 
 38 /**
 39  * ecryptfs_alloc_inode - allocate an ecryptfs inode
 40  * @sb: Pointer to the ecryptfs super block
 41  *
 42  * Called to bring an inode into existence.
 43  *
 44  * Only handle allocation, setting up structures should be done in
 45  * ecryptfs_read_inode. This is because the kernel, between now and
 46  * then, will 0 out the private data pointer.
 47  *
 48  * Returns a pointer to a newly allocated inode, NULL otherwise
 49  */
 50 static struct inode *ecryptfs_alloc_inode(struct super_block *sb)
 51 {
 52         struct ecryptfs_inode_info *inode_info;
 53         struct inode *inode = NULL;
 54 
 55         inode_info = kmem_cache_alloc(ecryptfs_inode_info_cache, GFP_KERNEL);
 56         if (unlikely(!inode_info))
 57                 goto out;
 58         ecryptfs_init_crypt_stat(&inode_info->crypt_stat);
 59         mutex_init(&inode_info->lower_file_mutex);
 60         atomic_set(&inode_info->lower_file_count, 0);
 61         inode_info->lower_file = NULL;
 62         inode = &inode_info->vfs_inode;
 63 out:
 64         return inode;
 65 }
 66 
 67 static void ecryptfs_i_callback(struct rcu_head *head)
 68 {
 69         struct inode *inode = container_of(head, struct inode, i_rcu);
 70         struct ecryptfs_inode_info *inode_info;
 71         inode_info = ecryptfs_inode_to_private(inode);
 72 
 73         kmem_cache_free(ecryptfs_inode_info_cache, inode_info);
 74 }
 75 
 76 /**
 77  * ecryptfs_destroy_inode
 78  * @inode: The ecryptfs inode
 79  *
 80  * This is used during the final destruction of the inode.  All
 81  * allocation of memory related to the inode, including allocated
 82  * memory in the crypt_stat struct, will be released here.
 83  * There should be no chance that this deallocation will be missed.
 84  */
 85 static void ecryptfs_destroy_inode(struct inode *inode)
 86 {
 87         struct ecryptfs_inode_info *inode_info;
 88 
 89         inode_info = ecryptfs_inode_to_private(inode);
 90         BUG_ON(inode_info->lower_file);
 91         ecryptfs_destroy_crypt_stat(&inode_info->crypt_stat);
 92         call_rcu(&inode->i_rcu, ecryptfs_i_callback);
 93 }
 94 
 95 /**
 96  * ecryptfs_statfs
 97  * @sb: The ecryptfs super block
 98  * @buf: The struct kstatfs to fill in with stats
 99  *
100  * Get the filesystem statistics. Currently, we let this pass right through
101  * to the lower filesystem and take no action ourselves.
102  */
103 static int ecryptfs_statfs(struct dentry *dentry, struct kstatfs *buf)
104 {
105         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
106         int rc;
107 
108         if (!lower_dentry->d_sb->s_op->statfs)
109                 return -ENOSYS;
110 
111         rc = lower_dentry->d_sb->s_op->statfs(lower_dentry, buf);
112         if (rc)
113                 return rc;
114 
115         buf->f_type = ECRYPTFS_SUPER_MAGIC;
116         rc = ecryptfs_set_f_namelen(&buf->f_namelen, buf->f_namelen,
117                &ecryptfs_superblock_to_private(dentry->d_sb)->mount_crypt_stat);
118 
119         return rc;
120 }
121 
122 /**
123  * ecryptfs_evict_inode
124  * @inode - The ecryptfs inode
125  *
126  * Called by iput() when the inode reference count reached zero
127  * and the inode is not hashed anywhere.  Used to clear anything
128  * that needs to be, before the inode is completely destroyed and put
129  * on the inode free list. We use this to drop out reference to the
130  * lower inode.
131  */
132 static void ecryptfs_evict_inode(struct inode *inode)
133 {
134         truncate_inode_pages_final(&inode->i_data);
135         clear_inode(inode);
136         iput(ecryptfs_inode_to_lower(inode));
137 }
138 
139 /**
140  * ecryptfs_show_options
141  *
142  * Prints the mount options for a given superblock.
143  * Returns zero; does not fail.
144  */
145 static int ecryptfs_show_options(struct seq_file *m, struct dentry *root)
146 {
147         struct super_block *sb = root->d_sb;
148         struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
149                 &ecryptfs_superblock_to_private(sb)->mount_crypt_stat;
150         struct ecryptfs_global_auth_tok *walker;
151 
152         mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
153         list_for_each_entry(walker,
154                             &mount_crypt_stat->global_auth_tok_list,
155                             mount_crypt_stat_list) {
156                 if (walker->flags & ECRYPTFS_AUTH_TOK_FNEK)
157                         seq_printf(m, ",ecryptfs_fnek_sig=%s", walker->sig);
158                 else
159                         seq_printf(m, ",ecryptfs_sig=%s", walker->sig);
160         }
161         mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
162 
163         seq_printf(m, ",ecryptfs_cipher=%s",
164                 mount_crypt_stat->global_default_cipher_name);
165 
166         if (mount_crypt_stat->global_default_cipher_key_size)
167                 seq_printf(m, ",ecryptfs_key_bytes=%zd",
168                            mount_crypt_stat->global_default_cipher_key_size);
169         if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)
170                 seq_printf(m, ",ecryptfs_passthrough");
171         if (mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED)
172                 seq_printf(m, ",ecryptfs_xattr_metadata");
173         if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
174                 seq_printf(m, ",ecryptfs_encrypted_view");
175         if (mount_crypt_stat->flags & ECRYPTFS_UNLINK_SIGS)
176                 seq_printf(m, ",ecryptfs_unlink_sigs");
177         if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY)
178                 seq_printf(m, ",ecryptfs_mount_auth_tok_only");
179 
180         return 0;
181 }
182 
183 const struct super_operations ecryptfs_sops = {
184         .alloc_inode = ecryptfs_alloc_inode,
185         .destroy_inode = ecryptfs_destroy_inode,
186         .statfs = ecryptfs_statfs,
187         .remount_fs = NULL,
188         .evict_inode = ecryptfs_evict_inode,
189         .show_options = ecryptfs_show_options
190 };
191 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp