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