1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * (C) 2001 Clemson University and The University of Chicago
  4 *
  5 * See COPYING in top-level directory.
  6 */
  7
  8#include "protocol.h"
  9#include "orangefs-kernel.h"
 10#include "orangefs-bufmap.h"
 11#include <linux/posix_acl_xattr.h>
 12
 13struct posix_acl *orangefs_get_acl(struct inode *inode, int type, bool rcu)
 14{
 15	struct posix_acl *acl;
 16	int ret;
 17	char *key = NULL, *value = NULL;
 18
 19	if (rcu)
 20		return ERR_PTR(-ECHILD);
 21
 22	switch (type) {
 23	case ACL_TYPE_ACCESS:
 24		key = XATTR_NAME_POSIX_ACL_ACCESS;
 25		break;
 26	case ACL_TYPE_DEFAULT:
 27		key = XATTR_NAME_POSIX_ACL_DEFAULT;
 28		break;
 29	default:
 30		gossip_err("orangefs_get_acl: bogus value of type %d\n", type);
 31		return ERR_PTR(-EINVAL);
 32	}
 33	/*
 34	 * Rather than incurring a network call just to determine the exact
 35	 * length of the attribute, I just allocate a max length to save on
 36	 * the network call. Conceivably, we could pass NULL to
 37	 * orangefs_inode_getxattr() to probe the length of the value, but
 38	 * I don't do that for now.
 39	 */
 40	value = kmalloc(ORANGEFS_MAX_XATTR_VALUELEN, GFP_KERNEL);
 41	if (!value)
 42		return ERR_PTR(-ENOMEM);
 43
 44	gossip_debug(GOSSIP_ACL_DEBUG,
 45		     "inode %pU, key %s, type %d\n",
 46		     get_khandle_from_ino(inode),
 47		     key,
 48		     type);
 49	ret = orangefs_inode_getxattr(inode, key, value,
 50				      ORANGEFS_MAX_XATTR_VALUELEN);
 51	/* if the key exists, convert it to an in-memory rep */
 52	if (ret > 0) {
 53		acl = posix_acl_from_xattr(&init_user_ns, value, ret);
 54	} else if (ret == -ENODATA || ret == -ENOSYS) {
 55		acl = NULL;
 56	} else {
 57		gossip_err("inode %pU retrieving acl's failed with error %d\n",
 58			   get_khandle_from_ino(inode),
 59			   ret);
 60		acl = ERR_PTR(ret);
 61	}
 62	/* kfree(NULL) is safe, so don't worry if value ever got used */
 63	kfree(value);
 64	return acl;
 65}
 66
 67int __orangefs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 68{
 69	int error = 0;
 70	void *value = NULL;
 71	size_t size = 0;
 72	const char *name = NULL;
 73
 74	switch (type) {
 75	case ACL_TYPE_ACCESS:
 76		name = XATTR_NAME_POSIX_ACL_ACCESS;
 77		break;
 78	case ACL_TYPE_DEFAULT:
 79		name = XATTR_NAME_POSIX_ACL_DEFAULT;
 80		break;
 81	default:
 82		gossip_err("%s: invalid type %d!\n", __func__, type);
 83		return -EINVAL;
 84	}
 85
 86	gossip_debug(GOSSIP_ACL_DEBUG,
 87		     "%s: inode %pU, key %s type %d\n",
 88		     __func__, get_khandle_from_ino(inode),
 89		     name,
 90		     type);
 91
 92	if (acl) {
 93		size = posix_acl_xattr_size(acl->a_count);
 94		value = kmalloc(size, GFP_KERNEL);
 95		if (!value)
 96			return -ENOMEM;
 97
 98		error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
 99		if (error < 0)
100			goto out;
101	}
102
103	gossip_debug(GOSSIP_ACL_DEBUG,
104		     "%s: name %s, value %p, size %zd, acl %p\n",
105		     __func__, name, value, size, acl);
106	/*
107	 * Go ahead and set the extended attribute now. NOTE: Suppose acl
108	 * was NULL, then value will be NULL and size will be 0 and that
109	 * will xlate to a removexattr. However, we don't want removexattr
110	 * complain if attributes does not exist.
111	 */
112	error = orangefs_inode_setxattr(inode, name, value, size, 0);
113
114out:
115	kfree(value);
116	if (!error)
117		set_cached_acl(inode, type, acl);
118	return error;
119}
120
121int orangefs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
122		     struct posix_acl *acl, int type)
123{
124	int error;
125	struct iattr iattr;
126	int rc;
127	struct inode *inode = d_inode(dentry);
128
129	memset(&iattr, 0, sizeof iattr);
130
131	if (type == ACL_TYPE_ACCESS && acl) {
132		/*
133		 * posix_acl_update_mode checks to see if the permissions
134		 * described by the ACL can be encoded into the
135		 * object's mode. If so, it sets "acl" to NULL
136		 * and "mode" to the new desired value. It is up to
137		 * us to propagate the new mode back to the server...
138		 */
139		error = posix_acl_update_mode(&nop_mnt_idmap, inode,
140					      &iattr.ia_mode, &acl);
141		if (error) {
142			gossip_err("%s: posix_acl_update_mode err: %d\n",
143				   __func__,
144				   error);
145			return error;
146		}
147
148		if (inode->i_mode != iattr.ia_mode)
149			iattr.ia_valid = ATTR_MODE;
150
151	}
152
153	rc = __orangefs_set_acl(inode, acl, type);
154
155	if (!rc && (iattr.ia_valid == ATTR_MODE))
156		rc = __orangefs_setattr_mode(dentry, &iattr);
157
158	return rc;
159}