1 /* 2 * linux/fs/ext2/xattr_security.c 3 * Handler for storing security labels as extended attributes. 4 */ 5 6 #include <linux/module.h> 7 #include <linux/slab.h> 8 #include <linux/string.h> 9 #include <linux/fs.h> 10 #include <linux/ext2_fs.h> 11 #include <linux/security.h> 12 #include "xattr.h" 13 14 static size_t 15 ext2_xattr_security_list(struct dentry *dentry, char *list, size_t list_size, 16 const char *name, size_t name_len, int type) 17 { 18 const int prefix_len = XATTR_SECURITY_PREFIX_LEN; 19 const size_t total_len = prefix_len + name_len + 1; 20 21 if (list && total_len <= list_size) { 22 memcpy(list, XATTR_SECURITY_PREFIX, prefix_len); 23 memcpy(list+prefix_len, name, name_len); 24 list[prefix_len + name_len] = '\0'; 25 } 26 return total_len; 27 } 28 29 static int 30 ext2_xattr_security_get(struct dentry *dentry, const char *name, 31 void *buffer, size_t size, int type) 32 { 33 if (strcmp(name, "") == 0) 34 return -EINVAL; 35 return ext2_xattr_get(dentry->d_inode, EXT2_XATTR_INDEX_SECURITY, name, 36 buffer, size); 37 } 38 39 static int 40 ext2_xattr_security_set(struct dentry *dentry, const char *name, 41 const void *value, size_t size, int flags, int type) 42 { 43 if (strcmp(name, "") == 0) 44 return -EINVAL; 45 return ext2_xattr_set(dentry->d_inode, EXT2_XATTR_INDEX_SECURITY, name, 46 value, size, flags); 47 } 48 49 int ext2_initxattrs(struct inode *inode, const struct xattr *xattr_array, 50 void *fs_info) 51 { 52 const struct xattr *xattr; 53 int err = 0; 54 55 for (xattr = xattr_array; xattr->name != NULL; xattr++) { 56 err = ext2_xattr_set(inode, EXT2_XATTR_INDEX_SECURITY, 57 xattr->name, xattr->value, 58 xattr->value_len, 0); 59 if (err < 0) 60 break; 61 } 62 return err; 63 } 64 65 int 66 ext2_init_security(struct inode *inode, struct inode *dir, 67 const struct qstr *qstr) 68 { 69 return security_inode_init_security(inode, dir, qstr, 70 &ext2_initxattrs, NULL); 71 } 72 73 const struct xattr_handler ext2_xattr_security_handler = { 74 .prefix = XATTR_SECURITY_PREFIX, 75 .list = ext2_xattr_security_list, 76 .get = ext2_xattr_security_get, 77 .set = ext2_xattr_security_set, 78 }; 79