1/*
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright 2021 Lutz Donnerhacke
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above
13 *    copyright notice, this list of conditions and the following
14 *    disclaimer in the documentation and/or other materials provided
15 *    with the distribution.
16 * 3. Neither the name of the copyright holder nor the names of its
17 *    contributors may be used to endorse or promote products derived
18 *    from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
21 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
22 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS
25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
26 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
27 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
29 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
30 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
31 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34#include <sys/types.h>
35
36#include <arpa/inet.h>
37#include <netinet/ip.h>
38#include <netinet/udp.h>
39
40#ifndef _UTIL_H
41#define _UTIL_H
42
43/* common ip ranges */
44extern struct in_addr masq, pub, prv1, prv2, prv3, cgn, ext, ANY_ADDR;
45
46int		randcmp(const void *a, const void *b);
47void		hexdump(void *p, size_t len);
48struct ip *	ip_packet(u_char protocol, size_t len);
49struct udphdr * set_udp(struct ip *p, u_short sport, u_short dport);
50
51static inline int
52addr_eq(struct in_addr a, struct in_addr b)
53{
54	return a.s_addr == b.s_addr;
55}
56
57#define a2h(a)	ntohl(a.s_addr)
58
59static inline int
60rand_range(int min, int max)
61{
62	return min + rand()%(max - min);
63}
64
65#define NAT_CHECK(pip, src, dst, msq)	do {	\
66	int res;				\
67	int len = ntohs(pip->ip_len);		\
68	pip->ip_src = src;			\
69	pip->ip_dst = dst;			\
70	res = LibAliasOut(la, pip, len);	\
71	ATF_CHECK_MSG(res == PKT_ALIAS_OK,	\
72	    ">%d< not met PKT_ALIAS_OK", res);	\
73	ATF_CHECK(addr_eq(msq, pip->ip_src));	\
74	ATF_CHECK(addr_eq(dst, pip->ip_dst));	\
75} while(0)
76
77#define NAT_FAIL(pip, src, dst)	do {		\
78	int res;				\
79	int len = ntohs(pip->ip_len);		\
80	pip->ip_src = src;			\
81	pip->ip_dst = dst;			\
82	res = LibAliasOut(la, pip, len);	\
83	ATF_CHECK_MSG(res != PKT_ALIAS_OK,	\
84	    ">%d< not met !PKT_ALIAS_OK", res);	\
85	ATF_CHECK(addr_eq(src, pip->ip_src));	\
86	ATF_CHECK(addr_eq(dst, pip->ip_dst));	\
87} while(0)
88
89#define UNNAT_CHECK(pip, src, dst, rel)	do {	\
90	int res;				\
91	int len = ntohs(pip->ip_len);		\
92	pip->ip_src = src;			\
93	pip->ip_dst = dst;			\
94	res = LibAliasIn(la, pip, len);		\
95	ATF_CHECK_MSG(res == PKT_ALIAS_OK,	\
96	    ">%d< not met PKT_ALIAS_OK", res);	\
97	ATF_CHECK(addr_eq(src, pip->ip_src));	\
98	ATF_CHECK(addr_eq(rel, pip->ip_dst));	\
99} while(0)
100
101#define UNNAT_FAIL(pip, src, dst)	do {	\
102	int res;				\
103	int len = ntohs(pip->ip_len);		\
104	pip->ip_src = src;			\
105	pip->ip_dst = dst;			\
106	res = LibAliasIn(la, pip, len);		\
107	ATF_CHECK_MSG(res != PKT_ALIAS_OK,	\
108	    ">%d< not met !PKT_ALIAS_OK", res);	\
109	ATF_CHECK(addr_eq(src, pip->ip_src));	\
110	ATF_CHECK(addr_eq(dst, pip->ip_dst));	\
111} while(0)
112
113#define UDP_NAT_CHECK(p, u, si, sp, di, dp, mi)	do {	\
114	u = set_udp(p, (sp), (dp));			\
115	NAT_CHECK(p, (si), (di), (mi));			\
116	ATF_CHECK(u->uh_dport == htons(dp));		\
117} while(0)
118
119#define UDP_NAT_FAIL(p, u, si, sp, di, dp)	do {	\
120	u = set_udp(p, (sp), (dp));			\
121	NAT_FAIL(p, (si), (di));			\
122} while(0)
123
124#define UDP_UNNAT_CHECK(p, u, si, sp, mi, mp, di, dp)	\
125do {							\
126	u = set_udp(p, (sp), (mp));			\
127	UNNAT_CHECK(p, (si), (mi), (di));		\
128	ATF_CHECK(u->uh_sport == htons(sp));		\
129	ATF_CHECK(u->uh_dport == htons(dp));		\
130} while(0)
131
132#define UDP_UNNAT_FAIL(p, u, si, sp, mi, mp)	do {	\
133	u = set_udp(p, (sp), (mp));			\
134	UNNAT_FAIL(p, (si), (mi));			\
135} while(0)
136
137#endif /* _UTIL_H */
138