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-rw-r--r--fs/fuse/xattr.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c
new file mode 100644
index 000000000..0d3e7177f
--- /dev/null
+++ b/fs/fuse/xattr.c
@@ -0,0 +1,266 @@
+/*
+ * FUSE: Filesystem in Userspace
+ * Copyright (C) 2001-2016 Miklos Szeredi <miklos@szeredi.hu>
+ *
+ * This program can be distributed under the terms of the GNU GPL.
+ * See the file COPYING.
+ */
+
+#include "fuse_i.h"
+
+#include <linux/xattr.h>
+#include <linux/posix_acl_xattr.h>
+
+int fuse_setxattr(struct inode *inode, const char *name, const void *value,
+ size_t size, int flags, unsigned int extra_flags)
+{
+ struct fuse_mount *fm = get_fuse_mount(inode);
+ FUSE_ARGS(args);
+ struct fuse_setxattr_in inarg;
+ int err;
+
+ if (fm->fc->no_setxattr)
+ return -EOPNOTSUPP;
+
+ memset(&inarg, 0, sizeof(inarg));
+ inarg.size = size;
+ inarg.flags = flags;
+ inarg.setxattr_flags = extra_flags;
+
+ args.opcode = FUSE_SETXATTR;
+ args.nodeid = get_node_id(inode);
+ args.in_numargs = 3;
+ args.in_args[0].size = fm->fc->setxattr_ext ?
+ sizeof(inarg) : FUSE_COMPAT_SETXATTR_IN_SIZE;
+ args.in_args[0].value = &inarg;
+ args.in_args[1].size = strlen(name) + 1;
+ args.in_args[1].value = name;
+ args.in_args[2].size = size;
+ args.in_args[2].value = value;
+ err = fuse_simple_request(fm, &args);
+ if (err == -ENOSYS) {
+ fm->fc->no_setxattr = 1;
+ err = -EOPNOTSUPP;
+ }
+ if (!err)
+ fuse_update_ctime(inode);
+
+ return err;
+}
+
+ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
+ size_t size)
+{
+ struct fuse_mount *fm = get_fuse_mount(inode);
+ FUSE_ARGS(args);
+ struct fuse_getxattr_in inarg;
+ struct fuse_getxattr_out outarg;
+ ssize_t ret;
+
+ if (fm->fc->no_getxattr)
+ return -EOPNOTSUPP;
+
+ memset(&inarg, 0, sizeof(inarg));
+ inarg.size = size;
+ args.opcode = FUSE_GETXATTR;
+ args.nodeid = get_node_id(inode);
+ args.in_numargs = 2;
+ args.in_args[0].size = sizeof(inarg);
+ args.in_args[0].value = &inarg;
+ args.in_args[1].size = strlen(name) + 1;
+ args.in_args[1].value = name;
+ /* This is really two different operations rolled into one */
+ args.out_numargs = 1;
+ if (size) {
+ args.out_argvar = true;
+ args.out_args[0].size = size;
+ args.out_args[0].value = value;
+ } else {
+ args.out_args[0].size = sizeof(outarg);
+ args.out_args[0].value = &outarg;
+ }
+ ret = fuse_simple_request(fm, &args);
+ if (!ret && !size)
+ ret = min_t(ssize_t, outarg.size, XATTR_SIZE_MAX);
+ if (ret == -ENOSYS) {
+ fm->fc->no_getxattr = 1;
+ ret = -EOPNOTSUPP;
+ }
+ return ret;
+}
+
+static int fuse_verify_xattr_list(char *list, size_t size)
+{
+ size_t origsize = size;
+
+ while (size) {
+ size_t thislen = strnlen(list, size);
+
+ if (!thislen || thislen == size)
+ return -EIO;
+
+ size -= thislen + 1;
+ list += thislen + 1;
+ }
+
+ return origsize;
+}
+
+ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size)
+{
+ struct inode *inode = d_inode(entry);
+ struct fuse_mount *fm = get_fuse_mount(inode);
+ FUSE_ARGS(args);
+ struct fuse_getxattr_in inarg;
+ struct fuse_getxattr_out outarg;
+ ssize_t ret;
+
+ if (fuse_is_bad(inode))
+ return -EIO;
+
+ if (!fuse_allow_current_process(fm->fc))
+ return -EACCES;
+
+ if (fm->fc->no_listxattr)
+ return -EOPNOTSUPP;
+
+ memset(&inarg, 0, sizeof(inarg));
+ inarg.size = size;
+ args.opcode = FUSE_LISTXATTR;
+ args.nodeid = get_node_id(inode);
+ args.in_numargs = 1;
+ args.in_args[0].size = sizeof(inarg);
+ args.in_args[0].value = &inarg;
+ /* This is really two different operations rolled into one */
+ args.out_numargs = 1;
+ if (size) {
+ args.out_argvar = true;
+ args.out_args[0].size = size;
+ args.out_args[0].value = list;
+ } else {
+ args.out_args[0].size = sizeof(outarg);
+ args.out_args[0].value = &outarg;
+ }
+ ret = fuse_simple_request(fm, &args);
+ if (!ret && !size)
+ ret = min_t(ssize_t, outarg.size, XATTR_LIST_MAX);
+ if (ret > 0 && size)
+ ret = fuse_verify_xattr_list(list, ret);
+ if (ret == -ENOSYS) {
+ fm->fc->no_listxattr = 1;
+ ret = -EOPNOTSUPP;
+ }
+ return ret;
+}
+
+int fuse_removexattr(struct inode *inode, const char *name)
+{
+ struct fuse_mount *fm = get_fuse_mount(inode);
+ FUSE_ARGS(args);
+ int err;
+
+ if (fm->fc->no_removexattr)
+ return -EOPNOTSUPP;
+
+ args.opcode = FUSE_REMOVEXATTR;
+ args.nodeid = get_node_id(inode);
+ args.in_numargs = 1;
+ args.in_args[0].size = strlen(name) + 1;
+ args.in_args[0].value = name;
+ err = fuse_simple_request(fm, &args);
+ if (err == -ENOSYS) {
+ fm->fc->no_removexattr = 1;
+ err = -EOPNOTSUPP;
+ }
+ if (!err)
+ fuse_update_ctime(inode);
+
+ return err;
+}
+
+static int fuse_xattr_get(const struct xattr_handler *handler,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, void *value, size_t size)
+{
+ if (fuse_is_bad(inode))
+ return -EIO;
+
+ return fuse_getxattr(inode, name, value, size);
+}
+
+static int fuse_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, const void *value, size_t size,
+ int flags)
+{
+ if (fuse_is_bad(inode))
+ return -EIO;
+
+ if (!value)
+ return fuse_removexattr(inode, name);
+
+ return fuse_setxattr(inode, name, value, size, flags, 0);
+}
+
+static bool no_xattr_list(struct dentry *dentry)
+{
+ return false;
+}
+
+static int no_xattr_get(const struct xattr_handler *handler,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, void *value, size_t size)
+{
+ return -EOPNOTSUPP;
+}
+
+static int no_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *mnt_userns,
+ struct dentry *dentry, struct inode *nodee,
+ const char *name, const void *value,
+ size_t size, int flags)
+{
+ return -EOPNOTSUPP;
+}
+
+static const struct xattr_handler fuse_xattr_handler = {
+ .prefix = "",
+ .get = fuse_xattr_get,
+ .set = fuse_xattr_set,
+};
+
+const struct xattr_handler *fuse_xattr_handlers[] = {
+ &fuse_xattr_handler,
+ NULL
+};
+
+const struct xattr_handler *fuse_acl_xattr_handlers[] = {
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
+ &fuse_xattr_handler,
+ NULL
+};
+
+static const struct xattr_handler fuse_no_acl_access_xattr_handler = {
+ .name = XATTR_NAME_POSIX_ACL_ACCESS,
+ .flags = ACL_TYPE_ACCESS,
+ .list = no_xattr_list,
+ .get = no_xattr_get,
+ .set = no_xattr_set,
+};
+
+static const struct xattr_handler fuse_no_acl_default_xattr_handler = {
+ .name = XATTR_NAME_POSIX_ACL_DEFAULT,
+ .flags = ACL_TYPE_ACCESS,
+ .list = no_xattr_list,
+ .get = no_xattr_get,
+ .set = no_xattr_set,
+};
+
+const struct xattr_handler *fuse_no_acl_xattr_handlers[] = {
+ &fuse_no_acl_access_xattr_handler,
+ &fuse_no_acl_default_xattr_handler,
+ &fuse_xattr_handler,
+ NULL
+};