1 #include <linux/reiserfs_fs.h> 2 #include <linux/errno.h> 3 #include <linux/fs.h> 4 #include <linux/pagemap.h> 5 #include <linux/xattr.h> 6 #include <linux/reiserfs_xattr.h> 7 #include <linux/security.h> 8 #include <asm/uaccess.h> 9 10 static int 11 security_get(struct dentry *dentry, const char *name, void *buffer, size_t size, 12 int handler_flags) 13 { 14 if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX)) 15 return -EINVAL; 16 17 if (IS_PRIVATE(dentry->d_inode)) 18 return -EPERM; 19 20 return reiserfs_xattr_get(dentry->d_inode, name, buffer, size); 21 } 22 23 static int 24 security_set(struct dentry *dentry, const char *name, const void *buffer, 25 size_t size, int flags, int handler_flags) 26 { 27 if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX)) 28 return -EINVAL; 29 30 if (IS_PRIVATE(dentry->d_inode)) 31 return -EPERM; 32 33 return reiserfs_xattr_set(dentry->d_inode, name, buffer, size, flags); 34 } 35 36 static size_t security_list(struct dentry *dentry, char *list, size_t list_len, 37 const char *name, size_t namelen, int handler_flags) 38 { 39 const size_t len = namelen + 1; 40 41 if (IS_PRIVATE(dentry->d_inode)) 42 return 0; 43 44 if (list && len <= list_len) { 45 memcpy(list, name, namelen); 46 list[namelen] = '\0'; 47 } 48 49 return len; 50 } 51 52 /* Initializes the security context for a new inode and returns the number 53 * of blocks needed for the transaction. If successful, reiserfs_security 54 * must be released using reiserfs_security_free when the caller is done. */ 55 int reiserfs_security_init(struct inode *dir, struct inode *inode, 56 struct reiserfs_security_handle *sec) 57 { 58 int blocks = 0; 59 int error; 60 61 sec->name = NULL; 62 63 /* Don't add selinux attributes on xattrs - they'll never get used */ 64 if (IS_PRIVATE(dir)) 65 return 0; 66 67 error = security_inode_init_security(inode, dir, &sec->name, 68 &sec->value, &sec->length); 69 if (error) { 70 if (error == -EOPNOTSUPP) 71 error = 0; 72 73 sec->name = NULL; 74 sec->value = NULL; 75 sec->length = 0; 76 return error; 77 } 78 79 if (sec->length) { 80 blocks = reiserfs_xattr_jcreate_nblocks(inode) + 81 reiserfs_xattr_nblocks(inode, sec->length); 82 /* We don't want to count the directories twice if we have 83 * a default ACL. */ 84 REISERFS_I(inode)->i_flags |= i_has_xattr_dir; 85 } 86 return blocks; 87 } 88 89 int reiserfs_security_write(struct reiserfs_transaction_handle *th, 90 struct inode *inode, 91 struct reiserfs_security_handle *sec) 92 { 93 int error; 94 if (strlen(sec->name) < sizeof(XATTR_SECURITY_PREFIX)) 95 return -EINVAL; 96 97 error = reiserfs_xattr_set_handle(th, inode, sec->name, sec->value, 98 sec->length, XATTR_CREATE); 99 if (error == -ENODATA || error == -EOPNOTSUPP) 100 error = 0; 101 102 return error; 103 } 104 105 void reiserfs_security_free(struct reiserfs_security_handle *sec) 106 { 107 kfree(sec->name); 108 kfree(sec->value); 109 sec->name = NULL; 110 sec->value = NULL; 111 } 112 113 struct xattr_handler reiserfs_xattr_security_handler = { 114 .prefix = XATTR_SECURITY_PREFIX, 115 .get = security_get, 116 .set = security_set, 117 .list = security_list, 118 }; 119