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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/crypto.h>
33#include <linux/statfs.h>
34#include <linux/magic.h>
35#include "ecryptfs_kernel.h"
36
37struct kmem_cache *ecryptfs_inode_info_cache;
38
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50
51static struct inode *ecryptfs_alloc_inode(struct super_block *sb)
52{
53 struct ecryptfs_inode_info *inode_info;
54 struct inode *inode = NULL;
55
56 inode_info = kmem_cache_alloc(ecryptfs_inode_info_cache, GFP_KERNEL);
57 if (unlikely(!inode_info))
58 goto out;
59 ecryptfs_init_crypt_stat(&inode_info->crypt_stat);
60 mutex_init(&inode_info->lower_file_mutex);
61 atomic_set(&inode_info->lower_file_count, 0);
62 inode_info->lower_file = NULL;
63 inode = &inode_info->vfs_inode;
64out:
65 return inode;
66}
67
68static void ecryptfs_i_callback(struct rcu_head *head)
69{
70 struct inode *inode = container_of(head, struct inode, i_rcu);
71 struct ecryptfs_inode_info *inode_info;
72 inode_info = ecryptfs_inode_to_private(inode);
73
74 kmem_cache_free(ecryptfs_inode_info_cache, inode_info);
75}
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85
86static void ecryptfs_destroy_inode(struct inode *inode)
87{
88 struct ecryptfs_inode_info *inode_info;
89
90 inode_info = ecryptfs_inode_to_private(inode);
91 BUG_ON(inode_info->lower_file);
92 ecryptfs_destroy_crypt_stat(&inode_info->crypt_stat);
93 call_rcu(&inode->i_rcu, ecryptfs_i_callback);
94}
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103
104static int ecryptfs_statfs(struct dentry *dentry, struct kstatfs *buf)
105{
106 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
107 int rc;
108
109 if (!lower_dentry->d_sb->s_op->statfs)
110 return -ENOSYS;
111
112 rc = lower_dentry->d_sb->s_op->statfs(lower_dentry, buf);
113 if (rc)
114 return rc;
115
116 buf->f_type = ECRYPTFS_SUPER_MAGIC;
117 rc = ecryptfs_set_f_namelen(&buf->f_namelen, buf->f_namelen,
118 &ecryptfs_superblock_to_private(dentry->d_sb)->mount_crypt_stat);
119
120 return rc;
121}
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132
133static void ecryptfs_evict_inode(struct inode *inode)
134{
135 truncate_inode_pages_final(&inode->i_data);
136 clear_inode(inode);
137 iput(ecryptfs_inode_to_lower(inode));
138}
139
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144
145
146static int ecryptfs_show_options(struct seq_file *m, struct dentry *root)
147{
148 struct super_block *sb = root->d_sb;
149 struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
150 &ecryptfs_superblock_to_private(sb)->mount_crypt_stat;
151 struct ecryptfs_global_auth_tok *walker;
152
153 mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
154 list_for_each_entry(walker,
155 &mount_crypt_stat->global_auth_tok_list,
156 mount_crypt_stat_list) {
157 if (walker->flags & ECRYPTFS_AUTH_TOK_FNEK)
158 seq_printf(m, ",ecryptfs_fnek_sig=%s", walker->sig);
159 else
160 seq_printf(m, ",ecryptfs_sig=%s", walker->sig);
161 }
162 mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
163
164 seq_printf(m, ",ecryptfs_cipher=%s",
165 mount_crypt_stat->global_default_cipher_name);
166
167 if (mount_crypt_stat->global_default_cipher_key_size)
168 seq_printf(m, ",ecryptfs_key_bytes=%zd",
169 mount_crypt_stat->global_default_cipher_key_size);
170 if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)
171 seq_printf(m, ",ecryptfs_passthrough");
172 if (mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED)
173 seq_printf(m, ",ecryptfs_xattr_metadata");
174 if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
175 seq_printf(m, ",ecryptfs_encrypted_view");
176 if (mount_crypt_stat->flags & ECRYPTFS_UNLINK_SIGS)
177 seq_printf(m, ",ecryptfs_unlink_sigs");
178 if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY)
179 seq_printf(m, ",ecryptfs_mount_auth_tok_only");
180
181 return 0;
182}
183
184const struct super_operations ecryptfs_sops = {
185 .alloc_inode = ecryptfs_alloc_inode,
186 .destroy_inode = ecryptfs_destroy_inode,
187 .statfs = ecryptfs_statfs,
188 .remount_fs = NULL,
189 .evict_inode = ecryptfs_evict_inode,
190 .show_options = ecryptfs_show_options
191};
192