This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / fs / generic_acl.c

diff --git a/fs/generic_acl.c b/fs/generic_acl.c
new file mode 100644 (file)
index 0000000..9ccb789
--- /dev/null
+++ b/fs/generic_acl.c
@@ -0,0 +1,197 @@
+/*
+ * fs/generic_acl.c
+ *
+ * (C) 2005 Andreas Gruenbacher <agruen@suse.de>
+ *
+ * This file is released under the GPL.
+ */
+
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/generic_acl.h>
+
+/**
+ * generic_acl_list  -  Generic xattr_handler->list() operation
+ * @ops:       Filesystem specific getacl and setacl callbacks
+ */
+size_t
+generic_acl_list(struct inode *inode, struct generic_acl_operations *ops,
+                int type, char *list, size_t list_size)
+{
+       struct posix_acl *acl;
+       const char *name;
+       size_t size;
+
+       acl = ops->getacl(inode, type);
+       if (!acl)
+               return 0;
+       posix_acl_release(acl);
+
+       switch(type) {
+               case ACL_TYPE_ACCESS:
+                       name = POSIX_ACL_XATTR_ACCESS;
+                       break;
+
+               case ACL_TYPE_DEFAULT:
+                       name = POSIX_ACL_XATTR_DEFAULT;
+                       break;
+
+               default:
+                       return 0;
+       }
+       size = strlen(name) + 1;
+       if (list && size <= list_size)
+               memcpy(list, name, size);
+       return size;
+}
+
+/**
+ * generic_acl_get  -  Generic xattr_handler->get() operation
+ * @ops:       Filesystem specific getacl and setacl callbacks
+ */
+int
+generic_acl_get(struct inode *inode, struct generic_acl_operations *ops,
+               int type, void *buffer, size_t size)
+{
+       struct posix_acl *acl;
+       int error;
+
+       acl = ops->getacl(inode, type);
+       if (!acl)
+               return -ENODATA;
+       error = posix_acl_to_xattr(acl, buffer, size);
+       posix_acl_release(acl);
+
+       return error;
+}
+
+/**
+ * generic_acl_set  -  Generic xattr_handler->set() operation
+ * @ops:       Filesystem specific getacl and setacl callbacks
+ */
+int
+generic_acl_set(struct inode *inode, struct generic_acl_operations *ops,
+               int type, const void *value, size_t size)
+{
+       struct posix_acl *acl = NULL;
+       int error;
+
+       if (S_ISLNK(inode->i_mode))
+               return -EOPNOTSUPP;
+       if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER))
+               return -EPERM;
+       if (value) {
+               acl = posix_acl_from_xattr(value, size);
+               if (IS_ERR(acl))
+                       return PTR_ERR(acl);
+       }
+       if (acl) {
+               mode_t mode;
+
+               error = posix_acl_valid(acl);
+               if (error)
+                       goto failed;
+               switch(type) {
+                       case ACL_TYPE_ACCESS:
+                               mode = inode->i_mode;
+                               error = posix_acl_equiv_mode(acl, &mode);
+                               if (error < 0)
+                                       goto failed;
+                               inode->i_mode = mode;
+                               if (error == 0) {
+                                       posix_acl_release(acl);
+                                       acl = NULL;
+                               }
+                               break;
+
+                       case ACL_TYPE_DEFAULT:
+                               if (!S_ISDIR(inode->i_mode)) {
+                                       error = -EINVAL;
+                                       goto failed;
+                               }
+                               break;
+               }
+       }
+       ops->setacl(inode, type, acl);
+       error = 0;
+failed:
+       posix_acl_release(acl);
+       return error;
+}
+
+/**
+ * generic_acl_init  -  Take care of acl inheritance at @inode create time
+ * @ops:       Filesystem specific getacl and setacl callbacks
+ *
+ * Files created inside a directory with a default ACL inherit the
+ * directory's default ACL.
+ */
+int
+generic_acl_init(struct inode *inode, struct inode *dir,
+                struct generic_acl_operations *ops)
+{
+       struct posix_acl *acl = NULL;
+       mode_t mode = inode->i_mode;
+       int error;
+
+       inode->i_mode = mode & ~current->fs->umask;
+       if (!S_ISLNK(inode->i_mode))
+               acl = ops->getacl(dir, ACL_TYPE_DEFAULT);
+       if (acl) {
+               struct posix_acl *clone;
+
+               if (S_ISDIR(inode->i_mode)) {
+                       clone = posix_acl_clone(acl, GFP_KERNEL);
+                       error = -ENOMEM;
+                       if (!clone)
+                               goto cleanup;
+                       ops->setacl(inode, ACL_TYPE_DEFAULT, clone);
+                       posix_acl_release(clone);
+               }
+               clone = posix_acl_clone(acl, GFP_KERNEL);
+               error = -ENOMEM;
+               if (!clone)
+                       goto cleanup;
+               error = posix_acl_create_masq(clone, &mode);
+               if (error >= 0) {
+                       inode->i_mode = mode;
+                       if (error > 0)
+                               ops->setacl(inode, ACL_TYPE_ACCESS, clone);
+               }
+               posix_acl_release(clone);
+       }
+       error = 0;
+
+cleanup:
+       posix_acl_release(acl);
+       return error;
+}
+
+/**
+ * generic_acl_chmod  -  change the access acl of @inode upon chmod()
+ * @ops:       FIlesystem specific getacl and setacl callbacks
+ *
+ * A chmod also changes the permissions of the owner, group/mask, and
+ * other ACL entries.
+ */
+int
+generic_acl_chmod(struct inode *inode, struct generic_acl_operations *ops)
+{
+       struct posix_acl *acl, *clone;
+       int error = 0;
+
+       if (S_ISLNK(inode->i_mode))
+               return -EOPNOTSUPP;
+       acl = ops->getacl(inode, ACL_TYPE_ACCESS);
+       if (acl) {
+               clone = posix_acl_clone(acl, GFP_KERNEL);
+               posix_acl_release(acl);
+               if (!clone)
+                       return -ENOMEM;
+               error = posix_acl_chmod_masq(clone, inode->i_mode);
+               if (!error)
+                       ops->setacl(inode, ACL_TYPE_ACCESS, clone);
+               posix_acl_release(clone);
+       }
+       return error;
+}