1 /* 2 * Copyright (C) International Business Machines Corp., 2002-2004 3 * Copyright (C) Andreas Gruenbacher, 2001 4 * Copyright (C) Linus Torvalds, 1991, 1992 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 14 * the GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 */ 20 21 #include <linux/sched.h> 22 #include <linux/fs.h> 23 #include <linux/quotaops.h> 24 #include "jfs_incore.h" 25 #include "jfs_xattr.h" 26 #include "jfs_acl.h" 27 28 static struct posix_acl *jfs_get_acl(struct inode *inode, int type) 29 { 30 struct posix_acl *acl; 31 char *ea_name; 32 struct jfs_inode_info *ji = JFS_IP(inode); 33 struct posix_acl **p_acl; 34 int size; 35 char *value = NULL; 36 37 switch(type) { 38 case ACL_TYPE_ACCESS: 39 ea_name = XATTR_NAME_ACL_ACCESS; 40 p_acl = &ji->i_acl; 41 break; 42 case ACL_TYPE_DEFAULT: 43 ea_name = XATTR_NAME_ACL_DEFAULT; 44 p_acl = &ji->i_default_acl; 45 break; 46 default: 47 return ERR_PTR(-EINVAL); 48 } 49 50 if (*p_acl != JFS_ACL_NOT_CACHED) 51 return posix_acl_dup(*p_acl); 52 53 size = __jfs_getxattr(inode, ea_name, NULL, 0); 54 55 if (size > 0) { 56 value = kmalloc(size, GFP_KERNEL); 57 if (!value) 58 return ERR_PTR(-ENOMEM); 59 size = __jfs_getxattr(inode, ea_name, value, size); 60 } 61 62 if (size < 0) { 63 if (size == -ENODATA) { 64 *p_acl = NULL; 65 acl = NULL; 66 } else 67 acl = ERR_PTR(size); 68 } else { 69 acl = posix_acl_from_xattr(value, size); 70 if (!IS_ERR(acl)) 71 *p_acl = posix_acl_dup(acl); 72 } 73 if (value) 74 kfree(value); 75 return acl; 76 } 77 78 static int jfs_set_acl(struct inode *inode, int type, struct posix_acl *acl) 79 { 80 char *ea_name; 81 struct jfs_inode_info *ji = JFS_IP(inode); 82 struct posix_acl **p_acl; 83 int rc; 84 int size = 0; 85 char *value = NULL; 86 87 if (S_ISLNK(inode->i_mode)) 88 return -EOPNOTSUPP; 89 90 switch(type) { 91 case ACL_TYPE_ACCESS: 92 ea_name = XATTR_NAME_ACL_ACCESS; 93 p_acl = &ji->i_acl; 94 break; 95 case ACL_TYPE_DEFAULT: 96 ea_name = XATTR_NAME_ACL_DEFAULT; 97 p_acl = &ji->i_default_acl; 98 if (!S_ISDIR(inode->i_mode)) 99 return acl ? -EACCES : 0; 100 break; 101 default: 102 return -EINVAL; 103 } 104 if (acl) { 105 size = xattr_acl_size(acl->a_count); 106 value = kmalloc(size, GFP_KERNEL); 107 if (!value) 108 return -ENOMEM; 109 rc = posix_acl_to_xattr(acl, value, size); 110 if (rc < 0) 111 goto out; 112 } 113 rc = __jfs_setxattr(inode, ea_name, value, size, 0); 114 out: 115 if (value) 116 kfree(value); 117 118 if (!rc) { 119 if (*p_acl && (*p_acl != JFS_ACL_NOT_CACHED)) 120 posix_acl_release(*p_acl); 121 *p_acl = posix_acl_dup(acl); 122 } 123 return rc; 124 } 125 126 static int jfs_check_acl(struct inode *inode, int mask) 127 { 128 struct jfs_inode_info *ji = JFS_IP(inode); 129 130 if (ji->i_acl == JFS_ACL_NOT_CACHED) { 131 struct posix_acl *acl = jfs_get_acl(inode, ACL_TYPE_ACCESS); 132 if (IS_ERR(acl)) 133 return PTR_ERR(acl); 134 posix_acl_release(acl); 135 } 136 137 if (ji->i_acl) 138 return posix_acl_permission(inode, ji->i_acl, mask); 139 return -EAGAIN; 140 } 141 142 int jfs_permission(struct inode *inode, int mask, struct nameidata *nd) 143 { 144 return generic_permission(inode, mask, jfs_check_acl); 145 } 146 147 int jfs_init_acl(struct inode *inode, struct inode *dir) 148 { 149 struct posix_acl *acl = NULL; 150 struct posix_acl *clone; 151 mode_t mode; 152 int rc = 0; 153 154 if (S_ISLNK(inode->i_mode)) 155 return 0; 156 157 acl = jfs_get_acl(dir, ACL_TYPE_DEFAULT); 158 if (IS_ERR(acl)) 159 return PTR_ERR(acl); 160 161 if (acl) { 162 if (S_ISDIR(inode->i_mode)) { 163 rc = jfs_set_acl(inode, ACL_TYPE_DEFAULT, acl); 164 if (rc) 165 goto cleanup; 166 } 167 clone = posix_acl_clone(acl, GFP_KERNEL); 168 if (!clone) { 169 rc = -ENOMEM; 170 goto cleanup; 171 } 172 mode = inode->i_mode; 173 rc = posix_acl_create_masq(clone, &mode); 174 if (rc >= 0) { 175 inode->i_mode = mode; 176 if (rc > 0) 177 rc = jfs_set_acl(inode, ACL_TYPE_ACCESS, clone); 178 } 179 posix_acl_release(clone); 180 cleanup: 181 posix_acl_release(acl); 182 } else 183 inode->i_mode &= ~current->fs->umask; 184 185 return rc; 186 } 187 188 static int jfs_acl_chmod(struct inode *inode) 189 { 190 struct posix_acl *acl, *clone; 191 int rc; 192 193 if (S_ISLNK(inode->i_mode)) 194 return -EOPNOTSUPP; 195 196 acl = jfs_get_acl(inode, ACL_TYPE_ACCESS); 197 if (IS_ERR(acl) || !acl) 198 return PTR_ERR(acl); 199 200 clone = posix_acl_clone(acl, GFP_KERNEL); 201 posix_acl_release(acl); 202 if (!clone) 203 return -ENOMEM; 204 205 rc = posix_acl_chmod_masq(clone, inode->i_mode); 206 if (!rc) 207 rc = jfs_set_acl(inode, ACL_TYPE_ACCESS, clone); 208 209 posix_acl_release(clone); 210 return rc; 211 } 212 213 int jfs_setattr(struct dentry *dentry, struct iattr *iattr) 214 { 215 struct inode *inode = dentry->d_inode; 216 int rc; 217 218 rc = inode_change_ok(inode, iattr); 219 if (rc) 220 return rc; 221 222 if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) || 223 (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) { 224 if (DQUOT_TRANSFER(inode, iattr)) 225 return -EDQUOT; 226 } 227 228 rc = inode_setattr(inode, iattr); 229 230 if (!rc && (iattr->ia_valid & ATTR_MODE)) 231 rc = jfs_acl_chmod(inode); 232 233 return rc; 234 } 235