1/*
  2 * (C) 2001 Clemson University and The University of Chicago
  3 *
  4 * See COPYING in top-level directory.
  5 */
  6
  7#include "protocol.h"
  8#include "orangefs-kernel.h"
  9#include "orangefs-bufmap.h"
 10#include <linux/posix_acl_xattr.h>
 11#include <linux/fs_struct.h>
 12
 13struct posix_acl *orangefs_get_acl(struct inode *inode, int type)
 14{
 15	struct posix_acl *acl;
 16	int ret;
 17	char *key = NULL, *value = NULL;
 18
 19	switch (type) {
 20	case ACL_TYPE_ACCESS:
 21		key = ORANGEFS_XATTR_NAME_ACL_ACCESS;
 22		break;
 23	case ACL_TYPE_DEFAULT:
 24		key = ORANGEFS_XATTR_NAME_ACL_DEFAULT;
 25		break;
 26	default:
 27		gossip_err("orangefs_get_acl: bogus value of type %d\n", type);
 28		return ERR_PTR(-EINVAL);
 29	}
 30	/*
 31	 * Rather than incurring a network call just to determine the exact
 32	 * length of the attribute, I just allocate a max length to save on
 33	 * the network call. Conceivably, we could pass NULL to
 34	 * orangefs_inode_getxattr() to probe the length of the value, but
 35	 * I don't do that for now.
 36	 */
 37	value = kmalloc(ORANGEFS_MAX_XATTR_VALUELEN, GFP_KERNEL);
 38	if (value == NULL)
 39		return ERR_PTR(-ENOMEM);
 40
 41	gossip_debug(GOSSIP_ACL_DEBUG,
 42		     "inode %pU, key %s, type %d\n",
 43		     get_khandle_from_ino(inode),
 44		     key,
 45		     type);
 46	ret = orangefs_inode_getxattr(inode,
 47				   "",
 48				   key,
 49				   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	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
 70	int error = 0;
 71	void *value = NULL;
 72	size_t size = 0;
 73	const char *name = NULL;
 74
 75	switch (type) {
 76	case ACL_TYPE_ACCESS:
 77		name = ORANGEFS_XATTR_NAME_ACL_ACCESS;
 78		if (acl) {
 79			umode_t mode = inode->i_mode;
 80			/*
 81			 * can we represent this with the traditional file
 82			 * mode permission bits?
 83			 */
 84			error = posix_acl_equiv_mode(acl, &mode);
 85			if (error < 0) {
 86				gossip_err("%s: posix_acl_equiv_mode err: %d\n",
 87					   __func__,
 88					   error);
 89				return error;
 90			}
 91
 92			if (inode->i_mode != mode)
 93				SetModeFlag(orangefs_inode);
 94			inode->i_mode = mode;
 95			mark_inode_dirty_sync(inode);
 96			if (error == 0)
 97				acl = NULL;
 98		}
 99		break;
100	case ACL_TYPE_DEFAULT:
101		name = ORANGEFS_XATTR_NAME_ACL_DEFAULT;
102		break;
103	default:
104		gossip_err("%s: invalid type %d!\n", __func__, type);
105		return -EINVAL;
106	}
107
108	gossip_debug(GOSSIP_ACL_DEBUG,
109		     "%s: inode %pU, key %s type %d\n",
110		     __func__, get_khandle_from_ino(inode),
111		     name,
112		     type);
113
114	if (acl) {
115		size = posix_acl_xattr_size(acl->a_count);
116		value = kmalloc(size, GFP_KERNEL);
117		if (!value)
118			return -ENOMEM;
119
120		error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
121		if (error < 0)
122			goto out;
123	}
124
125	gossip_debug(GOSSIP_ACL_DEBUG,
126		     "%s: name %s, value %p, size %zd, acl %p\n",
127		     __func__, name, value, size, acl);
128	/*
129	 * Go ahead and set the extended attribute now. NOTE: Suppose acl
130	 * was NULL, then value will be NULL and size will be 0 and that
131	 * will xlate to a removexattr. However, we don't want removexattr
132	 * complain if attributes does not exist.
133	 */
134	error = orangefs_inode_setxattr(inode, "", name, value, size, 0);
135
136out:
137	kfree(value);
138	if (!error)
139		set_cached_acl(inode, type, acl);
140	return error;
141}
142
143int orangefs_init_acl(struct inode *inode, struct inode *dir)
144{
145	struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
146	struct posix_acl *default_acl, *acl;
147	umode_t mode = inode->i_mode;
148	int error = 0;
149
150	ClearModeFlag(orangefs_inode);
151
152	error = posix_acl_create(dir, &mode, &default_acl, &acl);
153	if (error)
154		return error;
155
156	if (default_acl) {
157		error = orangefs_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
158		posix_acl_release(default_acl);
159	}
160
161	if (acl) {
162		if (!error)
163			error = orangefs_set_acl(inode, acl, ACL_TYPE_ACCESS);
164		posix_acl_release(acl);
165	}
166
167	/* If mode of the inode was changed, then do a forcible ->setattr */
168	if (mode != inode->i_mode) {
169		SetModeFlag(orangefs_inode);
170		inode->i_mode = mode;
171		orangefs_flush_inode(inode);
172	}
173
174	return error;
175}