1*85ff872dSAneesh Kumar K.V /* 2*85ff872dSAneesh Kumar K.V * Copyright IBM Corporation, 2010 3*85ff872dSAneesh Kumar K.V * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> 4*85ff872dSAneesh Kumar K.V * 5*85ff872dSAneesh Kumar K.V * This program is free software; you can redistribute it and/or modify it 6*85ff872dSAneesh Kumar K.V * under the terms of version 2.1 of the GNU Lesser General Public License 7*85ff872dSAneesh Kumar K.V * as published by the Free Software Foundation. 8*85ff872dSAneesh Kumar K.V * 9*85ff872dSAneesh Kumar K.V * This program is distributed in the hope that it would be useful, but 10*85ff872dSAneesh Kumar K.V * WITHOUT ANY WARRANTY; without even the implied warranty of 11*85ff872dSAneesh Kumar K.V * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 12*85ff872dSAneesh Kumar K.V * 13*85ff872dSAneesh Kumar K.V */ 14*85ff872dSAneesh Kumar K.V 15*85ff872dSAneesh Kumar K.V #include <linux/module.h> 16*85ff872dSAneesh Kumar K.V #include <linux/fs.h> 17*85ff872dSAneesh Kumar K.V #include <net/9p/9p.h> 18*85ff872dSAneesh Kumar K.V #include <net/9p/client.h> 19*85ff872dSAneesh Kumar K.V #include <linux/slab.h> 20*85ff872dSAneesh Kumar K.V #include <linux/posix_acl_xattr.h> 21*85ff872dSAneesh Kumar K.V #include "xattr.h" 22*85ff872dSAneesh Kumar K.V #include "acl.h" 23*85ff872dSAneesh Kumar K.V 24*85ff872dSAneesh Kumar K.V static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name) 25*85ff872dSAneesh Kumar K.V { 26*85ff872dSAneesh Kumar K.V ssize_t size; 27*85ff872dSAneesh Kumar K.V void *value = NULL; 28*85ff872dSAneesh Kumar K.V struct posix_acl *acl = NULL;; 29*85ff872dSAneesh Kumar K.V 30*85ff872dSAneesh Kumar K.V size = v9fs_fid_xattr_get(fid, name, NULL, 0); 31*85ff872dSAneesh Kumar K.V if (size > 0) { 32*85ff872dSAneesh Kumar K.V value = kzalloc(size, GFP_NOFS); 33*85ff872dSAneesh Kumar K.V if (!value) 34*85ff872dSAneesh Kumar K.V return ERR_PTR(-ENOMEM); 35*85ff872dSAneesh Kumar K.V size = v9fs_fid_xattr_get(fid, name, value, size); 36*85ff872dSAneesh Kumar K.V if (size > 0) { 37*85ff872dSAneesh Kumar K.V acl = posix_acl_from_xattr(value, size); 38*85ff872dSAneesh Kumar K.V if (IS_ERR(acl)) 39*85ff872dSAneesh Kumar K.V goto err_out; 40*85ff872dSAneesh Kumar K.V } 41*85ff872dSAneesh Kumar K.V } else if (size == -ENODATA || size == 0 || 42*85ff872dSAneesh Kumar K.V size == -ENOSYS || size == -EOPNOTSUPP) { 43*85ff872dSAneesh Kumar K.V acl = NULL; 44*85ff872dSAneesh Kumar K.V } else 45*85ff872dSAneesh Kumar K.V acl = ERR_PTR(-EIO); 46*85ff872dSAneesh Kumar K.V 47*85ff872dSAneesh Kumar K.V err_out: 48*85ff872dSAneesh Kumar K.V kfree(value); 49*85ff872dSAneesh Kumar K.V return acl; 50*85ff872dSAneesh Kumar K.V } 51*85ff872dSAneesh Kumar K.V 52*85ff872dSAneesh Kumar K.V int v9fs_get_acl(struct inode *inode, struct p9_fid *fid) 53*85ff872dSAneesh Kumar K.V { 54*85ff872dSAneesh Kumar K.V int retval = 0; 55*85ff872dSAneesh Kumar K.V struct posix_acl *pacl, *dacl; 56*85ff872dSAneesh Kumar K.V 57*85ff872dSAneesh Kumar K.V /* get the default/access acl values and cache them */ 58*85ff872dSAneesh Kumar K.V dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT); 59*85ff872dSAneesh Kumar K.V pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS); 60*85ff872dSAneesh Kumar K.V 61*85ff872dSAneesh Kumar K.V if (!IS_ERR(dacl) && !IS_ERR(pacl)) { 62*85ff872dSAneesh Kumar K.V set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl); 63*85ff872dSAneesh Kumar K.V set_cached_acl(inode, ACL_TYPE_ACCESS, pacl); 64*85ff872dSAneesh Kumar K.V posix_acl_release(dacl); 65*85ff872dSAneesh Kumar K.V posix_acl_release(pacl); 66*85ff872dSAneesh Kumar K.V } else 67*85ff872dSAneesh Kumar K.V retval = -EIO; 68*85ff872dSAneesh Kumar K.V 69*85ff872dSAneesh Kumar K.V return retval; 70*85ff872dSAneesh Kumar K.V } 71*85ff872dSAneesh Kumar K.V 72*85ff872dSAneesh Kumar K.V static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type) 73*85ff872dSAneesh Kumar K.V { 74*85ff872dSAneesh Kumar K.V struct posix_acl *acl; 75*85ff872dSAneesh Kumar K.V /* 76*85ff872dSAneesh Kumar K.V * 9p Always cache the acl value when 77*85ff872dSAneesh Kumar K.V * instantiating the inode (v9fs_inode_from_fid) 78*85ff872dSAneesh Kumar K.V */ 79*85ff872dSAneesh Kumar K.V acl = get_cached_acl(inode, type); 80*85ff872dSAneesh Kumar K.V BUG_ON(acl == ACL_NOT_CACHED); 81*85ff872dSAneesh Kumar K.V return acl; 82*85ff872dSAneesh Kumar K.V } 83*85ff872dSAneesh Kumar K.V 84*85ff872dSAneesh Kumar K.V int v9fs_check_acl(struct inode *inode, int mask) 85*85ff872dSAneesh Kumar K.V { 86*85ff872dSAneesh Kumar K.V struct posix_acl *acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS); 87*85ff872dSAneesh Kumar K.V 88*85ff872dSAneesh Kumar K.V if (IS_ERR(acl)) 89*85ff872dSAneesh Kumar K.V return PTR_ERR(acl); 90*85ff872dSAneesh Kumar K.V if (acl) { 91*85ff872dSAneesh Kumar K.V int error = posix_acl_permission(inode, acl, mask); 92*85ff872dSAneesh Kumar K.V posix_acl_release(acl); 93*85ff872dSAneesh Kumar K.V return error; 94*85ff872dSAneesh Kumar K.V } 95*85ff872dSAneesh Kumar K.V return -EAGAIN; 96*85ff872dSAneesh Kumar K.V } 97