acl.c 5.5 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
/*
 *   Copyright (C) International Business Machines  Corp., 2002-2004
 *   Copyright (C) Andreas Gruenbacher, 2001
 *   Copyright (C) Linus Torvalds, 1991, 1992
 *
 *   This program is free software;  you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or 
 *   (at your option) any later version.
 * 
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program;  if not, write to the Free Software 
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/quotaops.h>
24
#include <linux/posix_acl_xattr.h>
L
Linus Torvalds 已提交
25
#include "jfs_incore.h"
26
#include "jfs_txnmgr.h"
L
Linus Torvalds 已提交
27 28 29 30 31 32 33 34 35 36 37 38 39 40
#include "jfs_xattr.h"
#include "jfs_acl.h"

static struct posix_acl *jfs_get_acl(struct inode *inode, int type)
{
	struct posix_acl *acl;
	char *ea_name;
	struct jfs_inode_info *ji = JFS_IP(inode);
	struct posix_acl **p_acl;
	int size;
	char *value = NULL;

	switch(type) {
		case ACL_TYPE_ACCESS:
41
			ea_name = POSIX_ACL_XATTR_ACCESS;
L
Linus Torvalds 已提交
42 43 44
			p_acl = &ji->i_acl;
			break;
		case ACL_TYPE_DEFAULT:
45
			ea_name = POSIX_ACL_XATTR_DEFAULT;
L
Linus Torvalds 已提交
46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74
			p_acl = &ji->i_default_acl;
			break;
		default:
			return ERR_PTR(-EINVAL);
	}

	if (*p_acl != JFS_ACL_NOT_CACHED)
		return posix_acl_dup(*p_acl);

	size = __jfs_getxattr(inode, ea_name, NULL, 0);

	if (size > 0) {
		value = kmalloc(size, GFP_KERNEL);
		if (!value)
			return ERR_PTR(-ENOMEM);
		size = __jfs_getxattr(inode, ea_name, value, size);
	}

	if (size < 0) {
		if (size == -ENODATA) {
			*p_acl = NULL;
			acl = NULL;
		} else
			acl = ERR_PTR(size);
	} else {
		acl = posix_acl_from_xattr(value, size);
		if (!IS_ERR(acl))
			*p_acl = posix_acl_dup(acl);
	}
75
	kfree(value);
L
Linus Torvalds 已提交
76 77 78
	return acl;
}

79 80
static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
		       struct posix_acl *acl)
L
Linus Torvalds 已提交
81 82 83 84 85 86 87 88 89 90 91 92 93
{
	char *ea_name;
	struct jfs_inode_info *ji = JFS_IP(inode);
	struct posix_acl **p_acl;
	int rc;
	int size = 0;
	char *value = NULL;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	switch(type) {
		case ACL_TYPE_ACCESS:
94
			ea_name = POSIX_ACL_XATTR_ACCESS;
L
Linus Torvalds 已提交
95 96 97
			p_acl = &ji->i_acl;
			break;
		case ACL_TYPE_DEFAULT:
98
			ea_name = POSIX_ACL_XATTR_DEFAULT;
L
Linus Torvalds 已提交
99 100 101 102 103 104 105 106
			p_acl = &ji->i_default_acl;
			if (!S_ISDIR(inode->i_mode))
				return acl ? -EACCES : 0;
			break;
		default:
			return -EINVAL;
	}
	if (acl) {
107
		size = posix_acl_xattr_size(acl->a_count);
L
Linus Torvalds 已提交
108 109 110 111 112 113 114
		value = kmalloc(size, GFP_KERNEL);
		if (!value)
			return -ENOMEM;
		rc = posix_acl_to_xattr(acl, value, size);
		if (rc < 0)
			goto out;
	}
115
	rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0);
L
Linus Torvalds 已提交
116
out:
117
	kfree(value);
L
Linus Torvalds 已提交
118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147

	if (!rc) {
		if (*p_acl && (*p_acl != JFS_ACL_NOT_CACHED))
			posix_acl_release(*p_acl);
		*p_acl = posix_acl_dup(acl);
	}
	return rc;
}

static int jfs_check_acl(struct inode *inode, int mask)
{
	struct jfs_inode_info *ji = JFS_IP(inode);

	if (ji->i_acl == JFS_ACL_NOT_CACHED) {
		struct posix_acl *acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
		if (IS_ERR(acl))
			return PTR_ERR(acl);
		posix_acl_release(acl);
	}

	if (ji->i_acl)
		return posix_acl_permission(inode, ji->i_acl, mask);
	return -EAGAIN;
}

int jfs_permission(struct inode *inode, int mask, struct nameidata *nd)
{
	return generic_permission(inode, mask, jfs_check_acl);
}

148
int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir)
L
Linus Torvalds 已提交
149 150 151 152 153 154 155 156 157 158 159 160 161 162 163
{
	struct posix_acl *acl = NULL;
	struct posix_acl *clone;
	mode_t mode;
	int rc = 0;

	if (S_ISLNK(inode->i_mode))
		return 0;

	acl = jfs_get_acl(dir, ACL_TYPE_DEFAULT);
	if (IS_ERR(acl))
		return PTR_ERR(acl);

	if (acl) {
		if (S_ISDIR(inode->i_mode)) {
164
			rc = jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, acl);
L
Linus Torvalds 已提交
165 166 167 168 169 170 171 172 173 174 175 176 177
			if (rc)
				goto cleanup;
		}
		clone = posix_acl_clone(acl, GFP_KERNEL);
		if (!clone) {
			rc = -ENOMEM;
			goto cleanup;
		}
		mode = inode->i_mode;
		rc = posix_acl_create_masq(clone, &mode);
		if (rc >= 0) {
			inode->i_mode = mode;
			if (rc > 0)
178 179
				rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS,
						 clone);
L
Linus Torvalds 已提交
180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207
		}
		posix_acl_release(clone);
cleanup:
		posix_acl_release(acl);
	} else
		inode->i_mode &= ~current->fs->umask;

	return rc;
}

static int jfs_acl_chmod(struct inode *inode)
{
	struct posix_acl *acl, *clone;
	int rc;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	acl = jfs_get_acl(inode, ACL_TYPE_ACCESS);
	if (IS_ERR(acl) || !acl)
		return PTR_ERR(acl);

	clone = posix_acl_clone(acl, GFP_KERNEL);
	posix_acl_release(acl);
	if (!clone)
		return -ENOMEM;

	rc = posix_acl_chmod_masq(clone, inode->i_mode);
208 209 210 211 212 213 214 215 216
	if (!rc) {
		tid_t tid = txBegin(inode->i_sb, 0);
		down(&JFS_IP(inode)->commit_sem);
		rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, clone);
		if (!rc)
			rc = txCommit(tid, 1, &inode, 0);
		txEnd(tid);
		up(&JFS_IP(inode)->commit_sem);
	}
L
Linus Torvalds 已提交
217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243

	posix_acl_release(clone);
	return rc;
}

int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
{
	struct inode *inode = dentry->d_inode;
	int rc;

	rc = inode_change_ok(inode, iattr);
	if (rc)
		return rc;

	if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||
	    (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) {
		if (DQUOT_TRANSFER(inode, iattr))
			return -EDQUOT;
	}

	rc = inode_setattr(inode, iattr);

	if (!rc && (iattr->ia_valid & ATTR_MODE))
		rc = jfs_acl_chmod(inode);

	return rc;
}