/* * Copyright (c) 2017 Facebook * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. */#define KBUILD_MODNAME "foo"#include "vmlinux.h"#include <linux/version.h>#include <bpf/bpf_helpers.h>#include <bpf/bpf_tracing.h>#include <bpf/bpf_core_read.h> #define MAX_NR_PORTS 65536 #define EINVAL 22#define ENOENT 2 /* map #0 */struct inner_a {	__uint(type, BPF_MAP_TYPE_ARRAY);	__type(key, u32);	__type(value, int);	__uint(max_entries, MAX_NR_PORTS);} port_a SEC(".maps"); /* map #1 */struct inner_h {	__uint(type, BPF_MAP_TYPE_HASH);	__type(key, u32);	__type(value, int);	__uint(max_entries, 1);} port_h SEC(".maps"); /* map #2 */struct {	__uint(type, BPF_MAP_TYPE_HASH);	__type(key, u32);	__type(value, int);	__uint(max_entries, 1);} reg_result_h SEC(".maps"); /* map #3 */struct {	__uint(type, BPF_MAP_TYPE_HASH);	__type(key, u32);	__type(value, int);	__uint(max_entries, 1);} inline_result_h SEC(".maps"); /* map #4 */ /* Test case #0 */struct {	__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);	__uint(max_entries, MAX_NR_PORTS);	__uint(key_size, sizeof(u32));	__array(values, struct inner_a); /* use inner_a as inner map */} a_of_port_a SEC(".maps"); /* map #5 */ /* Test case #1 */struct {	__uint(type, BPF_MAP_TYPE_HASH_OF_MAPS);	__uint(max_entries, 1);	__uint(key_size, sizeof(u32));	__array(values, struct inner_a); /* use inner_a as inner map */} h_of_port_a SEC(".maps"); /* map #6 */ /* Test case #2 */struct {	__uint(type, BPF_MAP_TYPE_HASH_OF_MAPS);	__uint(max_entries, 1);	__uint(key_size, sizeof(u32));	__array(values, struct inner_h); /* use inner_h as inner map */} h_of_port_h SEC(".maps"); static __always_inline int do_reg_lookup(void *inner_map, u32 port){	int *result; 	result = bpf_map_lookup_elem(inner_map, &port);	return result ? *result : -ENOENT;} static __always_inline int do_inline_array_lookup(void *inner_map, u32 port){	int *result; 	if (inner_map != &port_a)		return -EINVAL; 	result = bpf_map_lookup_elem(&port_a, &port);	return result ? *result : -ENOENT;} static __always_inline int do_inline_hash_lookup(void *inner_map, u32 port){	int *result; 	if (inner_map != &port_h)		return -EINVAL; 	result = bpf_map_lookup_elem(&port_h, &port);	return result ? *result : -ENOENT;} SEC("ksyscall/connect")int BPF_KSYSCALL(trace_sys_connect, unsigned int fd, struct sockaddr_in6 *in6, int addrlen){	u16 test_case, port, dst6[8];	int ret, inline_ret, ret_key = 0;	u32 port_key;	void *outer_map, *inner_map;	bool inline_hash = false; 	if (addrlen != sizeof(*in6))		return 0; 	ret = bpf_probe_read_user(dst6, sizeof(dst6), &in6->sin6_addr);	if (ret) {		inline_ret = ret;		goto done;	} 	if (dst6[0] != 0xdead || dst6[1] != 0xbeef)		return 0; 	test_case = dst6[7]; 	ret = bpf_probe_read_user(&port, sizeof(port), &in6->sin6_port);	if (ret) {		inline_ret = ret;		goto done;	} 	port_key = port; 	ret = -ENOENT;	if (test_case == 0) {		outer_map = &a_of_port_a;	} else if (test_case == 1) {		outer_map = &h_of_port_a;	} else if (test_case == 2) {		outer_map = &h_of_port_h;	} else {		ret = __LINE__;		inline_ret = ret;		goto done;	} 	inner_map = bpf_map_lookup_elem(outer_map, &port_key);	if (!inner_map) {		ret = __LINE__;		inline_ret = ret;		goto done;	} 	ret = do_reg_lookup(inner_map, port_key); 	if (test_case == 0 || test_case == 1)		inline_ret = do_inline_array_lookup(inner_map, port_key);	else		inline_ret = do_inline_hash_lookup(inner_map, port_key); done:	bpf_map_update_elem(&reg_result_h, &ret_key, &ret, BPF_ANY);	bpf_map_update_elem(&inline_result_h, &ret_key, &inline_ret, BPF_ANY); 	return 0;} char _license[] SEC("license") = "GPL";u32 _version SEC("version") = LINUX_VERSION_CODE;