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/slab.h> 23 #include <linux/fs.h> 24 #include <linux/posix_acl_xattr.h> 25 #include "jfs_incore.h" 26 #include "jfs_txnmgr.h" 27 #include "jfs_xattr.h" 28 #include "jfs_acl.h" 29 30 static struct posix_acl *jfs_get_acl(struct inode *inode, int type) 31 { 32 struct posix_acl *acl; 33 char *ea_name; 34 int size; 35 char *value = NULL; 36 37 acl = get_cached_acl(inode, type); 38 if (acl != ACL_NOT_CACHED) 39 return acl; 40 41 switch(type) { 42 case ACL_TYPE_ACCESS: 43 ea_name = POSIX_ACL_XATTR_ACCESS; 44 break; 45 case ACL_TYPE_DEFAULT: 46 ea_name = POSIX_ACL_XATTR_DEFAULT; 47 break; 48 default: 49 return ERR_PTR(-EINVAL); 50 } 51 52 size = __jfs_getxattr(inode, ea_name, NULL, 0); 53 54 if (size > 0) { 55 value = kmalloc(size, GFP_KERNEL); 56 if (!value) 57 return ERR_PTR(-ENOMEM); 58 size = __jfs_getxattr(inode, ea_name, value, size); 59 } 60 61 if (size < 0) { 62 if (size == -ENODATA) 63 acl = NULL; 64 else 65 acl = ERR_PTR(size); 66 } else { 67 acl = posix_acl_from_xattr(value, size); 68 } 69 kfree(value); 70 if (!IS_ERR(acl)) 71 set_cached_acl(inode, type, acl); 72 return acl; 73 } 74 75 static int jfs_set_acl(tid_t tid, struct inode *inode, int type, 76 struct posix_acl *acl) 77 { 78 char *ea_name; 79 int rc; 80 int size = 0; 81 char *value = NULL; 82 83 if (S_ISLNK(inode->i_mode)) 84 return -EOPNOTSUPP; 85 86 switch(type) { 87 case ACL_TYPE_ACCESS: 88 ea_name = POSIX_ACL_XATTR_ACCESS; 89 break; 90 case ACL_TYPE_DEFAULT: 91 ea_name = POSIX_ACL_XATTR_DEFAULT; 92 if (!S_ISDIR(inode->i_mode)) 93 return acl ? -EACCES : 0; 94 break; 95 default: 96 return -EINVAL; 97 } 98 if (acl) { 99 size = posix_acl_xattr_size(acl->a_count); 100 value = kmalloc(size, GFP_KERNEL); 101 if (!value) 102 return -ENOMEM; 103 rc = posix_acl_to_xattr(acl, value, size); 104 if (rc < 0) 105 goto out; 106 } 107 rc = __jfs_setxattr(tid, inode, ea_name, value, size, 0); 108 out: 109 kfree(value); 110 111 if (!rc) 112 set_cached_acl(inode, type, acl); 113 114 return rc; 115 } 116 117 int jfs_check_acl(struct inode *inode, int mask, unsigned int flags) 118 { 119 struct posix_acl *acl; 120 121 if (flags & IPERM_FLAG_RCU) 122 return -ECHILD; 123 124 acl = jfs_get_acl(inode, ACL_TYPE_ACCESS); 125 if (IS_ERR(acl)) 126 return PTR_ERR(acl); 127 if (acl) { 128 int error = posix_acl_permission(inode, acl, mask); 129 posix_acl_release(acl); 130 return error; 131 } 132 133 return -EAGAIN; 134 } 135 136 int jfs_init_acl(tid_t tid, struct inode *inode, struct inode *dir) 137 { 138 struct posix_acl *acl = NULL; 139 struct posix_acl *clone; 140 mode_t mode; 141 int rc = 0; 142 143 if (S_ISLNK(inode->i_mode)) 144 return 0; 145 146 acl = jfs_get_acl(dir, ACL_TYPE_DEFAULT); 147 if (IS_ERR(acl)) 148 return PTR_ERR(acl); 149 150 if (acl) { 151 if (S_ISDIR(inode->i_mode)) { 152 rc = jfs_set_acl(tid, inode, ACL_TYPE_DEFAULT, acl); 153 if (rc) 154 goto cleanup; 155 } 156 clone = posix_acl_clone(acl, GFP_KERNEL); 157 if (!clone) { 158 rc = -ENOMEM; 159 goto cleanup; 160 } 161 mode = inode->i_mode; 162 rc = posix_acl_create_masq(clone, &mode); 163 if (rc >= 0) { 164 inode->i_mode = mode; 165 if (rc > 0) 166 rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, 167 clone); 168 } 169 posix_acl_release(clone); 170 cleanup: 171 posix_acl_release(acl); 172 } else 173 inode->i_mode &= ~current_umask(); 174 175 JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) | 176 inode->i_mode; 177 178 return rc; 179 } 180 181 int jfs_acl_chmod(struct inode *inode) 182 { 183 struct posix_acl *acl, *clone; 184 int rc; 185 186 if (S_ISLNK(inode->i_mode)) 187 return -EOPNOTSUPP; 188 189 acl = jfs_get_acl(inode, ACL_TYPE_ACCESS); 190 if (IS_ERR(acl) || !acl) 191 return PTR_ERR(acl); 192 193 clone = posix_acl_clone(acl, GFP_KERNEL); 194 posix_acl_release(acl); 195 if (!clone) 196 return -ENOMEM; 197 198 rc = posix_acl_chmod_masq(clone, inode->i_mode); 199 if (!rc) { 200 tid_t tid = txBegin(inode->i_sb, 0); 201 mutex_lock(&JFS_IP(inode)->commit_mutex); 202 rc = jfs_set_acl(tid, inode, ACL_TYPE_ACCESS, clone); 203 if (!rc) 204 rc = txCommit(tid, 1, &inode, 0); 205 txEnd(tid); 206 mutex_unlock(&JFS_IP(inode)->commit_mutex); 207 } 208 209 posix_acl_release(clone); 210 return rc; 211 } 212