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 <linux/posix_acl_xattr.h> 25 #include "jfs_incore.h" 26 #include "jfs_xattr.h" 27 #include "jfs_acl.h" 28 29 static struct posix_acl *jfs_get_acl(struct inode *inode, int type) 30 { 31 struct posix_acl *acl; 32 char *ea_name; 33 struct jfs_inode_info *ji = JFS_IP(inode); 34 struct posix_acl **p_acl; 35 int size; 36 char *value = NULL; 37 38 switch(type) { 39 case ACL_TYPE_ACCESS: 40 ea_name = POSIX_ACL_XATTR_ACCESS; 41 p_acl = &ji->i_acl; 42 break; 43 case ACL_TYPE_DEFAULT: 44 ea_name = POSIX_ACL_XATTR_DEFAULT; 45 p_acl = &ji->i_default_acl; 46 break; 47 default: 48 return ERR_PTR(-EINVAL); 49 } 50 51 if (*p_acl != JFS_ACL_NOT_CACHED) 52 return posix_acl_dup(*p_acl); 53 54 size = __jfs_getxattr(inode, ea_name, NULL, 0); 55 56 if (size > 0) { 57 value = kmalloc(size, GFP_KERNEL); 58 if (!value) 59 return ERR_PTR(-ENOMEM); 60 size = __jfs_getxattr(inode, ea_name, value, size); 61 } 62 63 if (size < 0) { 64 if (size == -ENODATA) { 65 *p_acl = NULL; 66 acl = NULL; 67 } else 68 acl = ERR_PTR(size); 69 } else { 70 acl = posix_acl_from_xattr(value, size); 71 if (!IS_ERR(acl)) 72 *p_acl = posix_acl_dup(acl); 73 } 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 = POSIX_ACL_XATTR_ACCESS; 93 p_acl = &ji->i_acl; 94 break; 95 case ACL_TYPE_DEFAULT: 96 ea_name = POSIX_ACL_XATTR_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 = posix_acl_xattr_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 kfree(value); 116 117 if (!rc) { 118 if (*p_acl && (*p_acl != JFS_ACL_NOT_CACHED)) 119 posix_acl_release(*p_acl); 120 *p_acl = posix_acl_dup(acl); 121 } 122 return rc; 123 } 124 125 static int jfs_check_acl(struct inode *inode, int mask) 126 { 127 struct jfs_inode_info *ji = JFS_IP(inode); 128 129 if (ji->i_acl == JFS_ACL_NOT_CACHED) { 130 struct posix_acl *acl = jfs_get_acl(inode, ACL_TYPE_ACCESS); 131 if (IS_ERR(acl)) 132 return PTR_ERR(acl); 133 posix_acl_release(acl); 134 } 135 136 if (ji->i_acl) 137 return posix_acl_permission(inode, ji->i_acl, mask); 138 return -EAGAIN; 139 } 140 141 int jfs_permission(struct inode *inode, int mask, struct nameidata *nd) 142 { 143 return generic_permission(inode, mask, jfs_check_acl); 144 } 145 146 int jfs_init_acl(struct inode *inode, struct inode *dir) 147 { 148 struct posix_acl *acl = NULL; 149 struct posix_acl *clone; 150 mode_t mode; 151 int rc = 0; 152 153 if (S_ISLNK(inode->i_mode)) 154 return 0; 155 156 acl = jfs_get_acl(dir, ACL_TYPE_DEFAULT); 157 if (IS_ERR(acl)) 158 return PTR_ERR(acl); 159 160 if (acl) { 161 if (S_ISDIR(inode->i_mode)) { 162 rc = jfs_set_acl(inode, ACL_TYPE_DEFAULT, acl); 163 if (rc) 164 goto cleanup; 165 } 166 clone = posix_acl_clone(acl, GFP_KERNEL); 167 if (!clone) { 168 rc = -ENOMEM; 169 goto cleanup; 170 } 171 mode = inode->i_mode; 172 rc = posix_acl_create_masq(clone, &mode); 173 if (rc >= 0) { 174 inode->i_mode = mode; 175 if (rc > 0) 176 rc = jfs_set_acl(inode, ACL_TYPE_ACCESS, clone); 177 } 178 posix_acl_release(clone); 179 cleanup: 180 posix_acl_release(acl); 181 } else 182 inode->i_mode &= ~current->fs->umask; 183 184 return rc; 185 } 186 187 static int jfs_acl_chmod(struct inode *inode) 188 { 189 struct posix_acl *acl, *clone; 190 int rc; 191 192 if (S_ISLNK(inode->i_mode)) 193 return -EOPNOTSUPP; 194 195 acl = jfs_get_acl(inode, ACL_TYPE_ACCESS); 196 if (IS_ERR(acl) || !acl) 197 return PTR_ERR(acl); 198 199 clone = posix_acl_clone(acl, GFP_KERNEL); 200 posix_acl_release(acl); 201 if (!clone) 202 return -ENOMEM; 203 204 rc = posix_acl_chmod_masq(clone, inode->i_mode); 205 if (!rc) 206 rc = jfs_set_acl(inode, ACL_TYPE_ACCESS, clone); 207 208 posix_acl_release(clone); 209 return rc; 210 } 211 212 int jfs_setattr(struct dentry *dentry, struct iattr *iattr) 213 { 214 struct inode *inode = dentry->d_inode; 215 int rc; 216 217 rc = inode_change_ok(inode, iattr); 218 if (rc) 219 return rc; 220 221 if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) || 222 (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) { 223 if (DQUOT_TRANSFER(inode, iattr)) 224 return -EDQUOT; 225 } 226 227 rc = inode_setattr(inode, iattr); 228 229 if (!rc && (iattr->ia_valid & ATTR_MODE)) 230 rc = jfs_acl_chmod(inode); 231 232 return rc; 233 } 234