1ac27a0ecSDave Kleikamp /* 2617ba13bSMingming Cao * linux/fs/ext4/xattr_security.c 3ac27a0ecSDave Kleikamp * Handler for storing security labels as extended attributes. 4ac27a0ecSDave Kleikamp */ 5ac27a0ecSDave Kleikamp 6ac27a0ecSDave Kleikamp #include <linux/module.h> 7ac27a0ecSDave Kleikamp #include <linux/string.h> 8ac27a0ecSDave Kleikamp #include <linux/fs.h> 9ac27a0ecSDave Kleikamp #include <linux/smp_lock.h> 10617ba13bSMingming Cao #include <linux/ext4_jbd.h> 11617ba13bSMingming Cao #include <linux/ext4_fs.h> 12ac27a0ecSDave Kleikamp #include <linux/security.h> 13ac27a0ecSDave Kleikamp #include "xattr.h" 14ac27a0ecSDave Kleikamp 15ac27a0ecSDave Kleikamp static size_t 16617ba13bSMingming Cao ext4_xattr_security_list(struct inode *inode, char *list, size_t list_size, 17ac27a0ecSDave Kleikamp const char *name, size_t name_len) 18ac27a0ecSDave Kleikamp { 19ac27a0ecSDave Kleikamp const size_t prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1; 20ac27a0ecSDave Kleikamp const size_t total_len = prefix_len + name_len + 1; 21ac27a0ecSDave Kleikamp 22ac27a0ecSDave Kleikamp 23ac27a0ecSDave Kleikamp if (list && total_len <= list_size) { 24ac27a0ecSDave Kleikamp memcpy(list, XATTR_SECURITY_PREFIX, prefix_len); 25ac27a0ecSDave Kleikamp memcpy(list+prefix_len, name, name_len); 26ac27a0ecSDave Kleikamp list[prefix_len + name_len] = '\0'; 27ac27a0ecSDave Kleikamp } 28ac27a0ecSDave Kleikamp return total_len; 29ac27a0ecSDave Kleikamp } 30ac27a0ecSDave Kleikamp 31ac27a0ecSDave Kleikamp static int 32617ba13bSMingming Cao ext4_xattr_security_get(struct inode *inode, const char *name, 33ac27a0ecSDave Kleikamp void *buffer, size_t size) 34ac27a0ecSDave Kleikamp { 35ac27a0ecSDave Kleikamp if (strcmp(name, "") == 0) 36ac27a0ecSDave Kleikamp return -EINVAL; 37617ba13bSMingming Cao return ext4_xattr_get(inode, EXT4_XATTR_INDEX_SECURITY, name, 38ac27a0ecSDave Kleikamp buffer, size); 39ac27a0ecSDave Kleikamp } 40ac27a0ecSDave Kleikamp 41ac27a0ecSDave Kleikamp static int 42617ba13bSMingming Cao ext4_xattr_security_set(struct inode *inode, const char *name, 43ac27a0ecSDave Kleikamp const void *value, size_t size, int flags) 44ac27a0ecSDave Kleikamp { 45ac27a0ecSDave Kleikamp if (strcmp(name, "") == 0) 46ac27a0ecSDave Kleikamp return -EINVAL; 47617ba13bSMingming Cao return ext4_xattr_set(inode, EXT4_XATTR_INDEX_SECURITY, name, 48ac27a0ecSDave Kleikamp value, size, flags); 49ac27a0ecSDave Kleikamp } 50ac27a0ecSDave Kleikamp 51ac27a0ecSDave Kleikamp int 52617ba13bSMingming Cao ext4_init_security(handle_t *handle, struct inode *inode, struct inode *dir) 53ac27a0ecSDave Kleikamp { 54ac27a0ecSDave Kleikamp int err; 55ac27a0ecSDave Kleikamp size_t len; 56ac27a0ecSDave Kleikamp void *value; 57ac27a0ecSDave Kleikamp char *name; 58ac27a0ecSDave Kleikamp 59ac27a0ecSDave Kleikamp err = security_inode_init_security(inode, dir, &name, &value, &len); 60ac27a0ecSDave Kleikamp if (err) { 61ac27a0ecSDave Kleikamp if (err == -EOPNOTSUPP) 62ac27a0ecSDave Kleikamp return 0; 63ac27a0ecSDave Kleikamp return err; 64ac27a0ecSDave Kleikamp } 65617ba13bSMingming Cao err = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_SECURITY, 66ac27a0ecSDave Kleikamp name, value, len, 0); 67ac27a0ecSDave Kleikamp kfree(name); 68ac27a0ecSDave Kleikamp kfree(value); 69ac27a0ecSDave Kleikamp return err; 70ac27a0ecSDave Kleikamp } 71ac27a0ecSDave Kleikamp 72617ba13bSMingming Cao struct xattr_handler ext4_xattr_security_handler = { 73ac27a0ecSDave Kleikamp .prefix = XATTR_SECURITY_PREFIX, 74617ba13bSMingming Cao .list = ext4_xattr_security_list, 75617ba13bSMingming Cao .get = ext4_xattr_security_get, 76617ba13bSMingming Cao .set = ext4_xattr_security_set, 77ac27a0ecSDave Kleikamp }; 78