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/security.h> 105a0e3ad6STejun Heo #include <linux/slab.h> 113dcf5451SChristoph Hellwig #include "ext4_jbd2.h" 123dcf5451SChristoph Hellwig #include "ext4.h" 13ac27a0ecSDave Kleikamp #include "xattr.h" 14ac27a0ecSDave Kleikamp 15ac27a0ecSDave Kleikamp static size_t 16431547b3SChristoph Hellwig ext4_xattr_security_list(struct dentry *dentry, char *list, size_t list_size, 17431547b3SChristoph Hellwig const char *name, size_t name_len, int type) 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 32431547b3SChristoph Hellwig ext4_xattr_security_get(struct dentry *dentry, const char *name, 33431547b3SChristoph Hellwig void *buffer, size_t size, int type) 34ac27a0ecSDave Kleikamp { 35ac27a0ecSDave Kleikamp if (strcmp(name, "") == 0) 36ac27a0ecSDave Kleikamp return -EINVAL; 37431547b3SChristoph Hellwig return ext4_xattr_get(dentry->d_inode, EXT4_XATTR_INDEX_SECURITY, 38431547b3SChristoph Hellwig name, buffer, size); 39ac27a0ecSDave Kleikamp } 40ac27a0ecSDave Kleikamp 41ac27a0ecSDave Kleikamp static int 42431547b3SChristoph Hellwig ext4_xattr_security_set(struct dentry *dentry, const char *name, 43431547b3SChristoph Hellwig const void *value, size_t size, int flags, int type) 44ac27a0ecSDave Kleikamp { 45ac27a0ecSDave Kleikamp if (strcmp(name, "") == 0) 46ac27a0ecSDave Kleikamp return -EINVAL; 47431547b3SChristoph Hellwig return ext4_xattr_set(dentry->d_inode, EXT4_XATTR_INDEX_SECURITY, 48431547b3SChristoph Hellwig name, value, size, flags); 49ac27a0ecSDave Kleikamp } 50ac27a0ecSDave Kleikamp 51ac27a0ecSDave Kleikamp int 522a7dba39SEric Paris ext4_init_security(handle_t *handle, struct inode *inode, struct inode *dir, 532a7dba39SEric Paris const struct qstr *qstr) 54ac27a0ecSDave Kleikamp { 55ac27a0ecSDave Kleikamp int err; 56ac27a0ecSDave Kleikamp size_t len; 57ac27a0ecSDave Kleikamp void *value; 58ac27a0ecSDave Kleikamp char *name; 59ac27a0ecSDave Kleikamp 602a7dba39SEric Paris err = security_inode_init_security(inode, dir, qstr, &name, &value, &len); 61ac27a0ecSDave Kleikamp if (err) { 62ac27a0ecSDave Kleikamp if (err == -EOPNOTSUPP) 63ac27a0ecSDave Kleikamp return 0; 64ac27a0ecSDave Kleikamp return err; 65ac27a0ecSDave Kleikamp } 66617ba13bSMingming Cao err = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_SECURITY, 67ac27a0ecSDave Kleikamp name, value, len, 0); 68ac27a0ecSDave Kleikamp kfree(name); 69ac27a0ecSDave Kleikamp kfree(value); 70ac27a0ecSDave Kleikamp return err; 71ac27a0ecSDave Kleikamp } 72ac27a0ecSDave Kleikamp 7311e27528SStephen Hemminger const struct xattr_handler ext4_xattr_security_handler = { 74ac27a0ecSDave Kleikamp .prefix = XATTR_SECURITY_PREFIX, 75617ba13bSMingming Cao .list = ext4_xattr_security_list, 76617ba13bSMingming Cao .get = ext4_xattr_security_get, 77617ba13bSMingming Cao .set = ext4_xattr_security_set, 78ac27a0ecSDave Kleikamp }; 79