# Copyright 2017 syzkaller project authors. All rights reserved.
# Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.

# AF_NETLINK/NETLINK_GENERIC support.

# TODO: describe APIs of specific genetlink families.

include <linux/net.h>
include <uapi/linux/netlink.h>
include <uapi/linux/genetlink.h>

resource sock_nl_generic[sock_netlink]

socket$nl_generic(domain const[AF_NETLINK], type const[SOCK_RAW], proto const[NETLINK_GENERIC]) sock_nl_generic (automatic_helper)

# This is NETLINK_GENERIC created in init_net namespace. Use with extreme care.
# It's very dangerous to use as it allows the fuzzer to bring down network connectivity
# and destroy the machine in other ways. But it's required for ieee802154 testing and
# some other netlink protocols that can be used only in init_net (.netnsok = false).
# It is specifically not derived from fd/sock, so that fuzzer does not try to use it other ways.
# However, it's still easy to abuse it since fd number is low and can easily be used
# as the result of race or something. If this proves to be problematic, we can either
# create a pseudo syscall that creates socket, moves it to a high fd and then changes namespace,
# and/or create a pseudo syscall that both creates the socket and send netlink message,
# or improve kernel to properly support namespaces for ieee802154.
resource sock_nl_generic_init[int32]: -1

syz_init_net_socket$nl_generic(domain const[AF_NETLINK], type const[SOCK_RAW], proto const[NETLINK_GENERIC]) sock_nl_generic_init

sendmsg$nl_generic(fd sock_nl_generic, msg ptr[in, msghdr_nl_generic], f flags[send_flags])

type msghdr_nl_generic msghdr_netlink[netlink_msg_t[netlink_random_msg_type, genlmsghdr, nl_generic_attr]]

genlmsghdr {
	cmd		int8[0:32]
	version		const[0, int8]
	reserved	const[0, int16]
} [align[4]]

type genlmsghdr_t[CMD] {
	cmd		const[CMD, int8]
	version		const[0, int8]
	reserved	const[0, int16]
} [align[4]]