diff options
Diffstat (limited to 'fs/fuse/xattr.c')
| -rw-r--r-- | fs/fuse/xattr.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c new file mode 100644 index 000000000000..3caac46b08b0 --- /dev/null +++ b/fs/fuse/xattr.c @@ -0,0 +1,211 @@ +/* + * 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) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + FUSE_ARGS(args); + struct fuse_setxattr_in inarg; + int err; + + if (fc->no_setxattr) + return -EOPNOTSUPP; + + memset(&inarg, 0, sizeof(inarg)); + inarg.size = size; + inarg.flags = flags; + args.in.h.opcode = FUSE_SETXATTR; + args.in.h.nodeid = get_node_id(inode); + args.in.numargs = 3; + 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; + args.in.args[2].size = size; + args.in.args[2].value = value; + err = fuse_simple_request(fc, &args); + if (err == -ENOSYS) { + fc->no_setxattr = 1; + err = -EOPNOTSUPP; + } + if (!err) { + fuse_invalidate_attr(inode); + fuse_update_ctime(inode); + } + return err; +} + +ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value, + size_t size) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + FUSE_ARGS(args); + struct fuse_getxattr_in inarg; + struct fuse_getxattr_out outarg; + ssize_t ret; + + if (fc->no_getxattr) + return -EOPNOTSUPP; + + memset(&inarg, 0, sizeof(inarg)); + inarg.size = size; + args.in.h.opcode = FUSE_GETXATTR; + args.in.h.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 = 1; + 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(fc, &args); + if (!ret && !size) + ret = min_t(ssize_t, outarg.size, XATTR_SIZE_MAX); + if (ret == -ENOSYS) { + 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_conn *fc = get_fuse_conn(inode); + FUSE_ARGS(args); + struct fuse_getxattr_in inarg; + struct fuse_getxattr_out outarg; + ssize_t ret; + + if (!fuse_allow_current_process(fc)) + return -EACCES; + + if (fc->no_listxattr) + return -EOPNOTSUPP; + + memset(&inarg, 0, sizeof(inarg)); + inarg.size = size; + args.in.h.opcode = FUSE_LISTXATTR; + args.in.h.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 = 1; + 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(fc, &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) { + fc->no_listxattr = 1; + ret = -EOPNOTSUPP; + } + return ret; +} + +int fuse_removexattr(struct inode *inode, const char *name) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + FUSE_ARGS(args); + int err; + + if (fc->no_removexattr) + return -EOPNOTSUPP; + + args.in.h.opcode = FUSE_REMOVEXATTR; + args.in.h.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(fc, &args); + if (err == -ENOSYS) { + fc->no_removexattr = 1; + err = -EOPNOTSUPP; + } + if (!err) { + fuse_invalidate_attr(inode); + 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) +{ + return fuse_getxattr(inode, name, value, size); +} + +static int fuse_xattr_set(const struct xattr_handler *handler, + struct dentry *dentry, struct inode *inode, + const char *name, const void *value, size_t size, + int flags) +{ + if (!value) + return fuse_removexattr(inode, name); + + return fuse_setxattr(inode, name, value, size, flags); +} + +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 +}; |