xref: /netbsd-src/usr.sbin/npf/npftest/libnpftest/npf_nat_test.c (revision a4ddc2c8fb9af816efe3b1c375a5530aef0e89e9)
1 /*	$NetBSD: npf_nat_test.c,v 1.2 2012/12/24 19:05:47 rmind Exp $	*/
2 
3 /*
4  * NPF NAT test.
5  *
6  * Public Domain.
7  */
8 
9 #include <sys/types.h>
10 
11 #include "npf_impl.h"
12 #include "npf_test.h"
13 
14 #define	IFNAME_EXT	"npftest0"
15 #define	IFNAME_INT	"npftest1"
16 
17 #define	LOCAL_IP1	"10.1.1.1"
18 #define	LOCAL_IP2	"10.1.1.2"
19 
20 /* Note: RFC 5737 compliant addresses. */
21 #define	PUB_IP1		"192.0.2.1"
22 #define	PUB_IP2		"192.0.2.2"
23 #define	REMOTE_IP1	"192.0.2.3"
24 #define	REMOTE_IP2	"192.0.2.4"
25 
26 #define	RESULT_PASS	0
27 #define	RESULT_BLOCK	ENETUNREACH
28 
29 #define	NPF_BINAT	(NPF_NATIN | NPF_NATOUT)
30 
31 static const struct test_case {
32 	const char *	src;
33 	in_port_t	sport;
34 	const char *	dst;
35 	in_port_t	dport;
36 	int		ttype;
37 	const char *	ifname;
38 	int		di;
39 	int		ret;
40 	const char *	taddr;
41 	in_port_t	tport;
42 } test_cases[] = {
43 
44 	/*
45 	 * Traditional NAPT (outbound NAT):
46 	 *	map $ext_if dynamic $local_net -> $pub_ip1
47 	 */
48 	{
49 		LOCAL_IP1,	15000,		REMOTE_IP1,	7000,
50 		NPF_NATOUT,	IFNAME_EXT,	PFIL_OUT,
51 		RESULT_PASS,	PUB_IP1,	53472
52 	},
53 	{
54 		LOCAL_IP1,	15000,		REMOTE_IP1,	7000,
55 		NPF_NATOUT,	IFNAME_EXT,	PFIL_OUT,
56 		RESULT_PASS,	PUB_IP1,	53472
57 	},
58 	{
59 		LOCAL_IP1,	15000,		REMOTE_IP1,	7000,
60 		NPF_NATOUT,	IFNAME_EXT,	PFIL_IN,
61 		RESULT_BLOCK,	NULL,		0
62 	},
63 	{
64 		REMOTE_IP1,	7000,		LOCAL_IP1,	15000,
65 		NPF_NATOUT,	IFNAME_EXT,	PFIL_IN,
66 		RESULT_BLOCK,	NULL,		0
67 	},
68 	{
69 		REMOTE_IP1,	7000,		PUB_IP1,	53472,
70 		NPF_NATOUT,	IFNAME_INT,	PFIL_IN,
71 		RESULT_BLOCK,	NULL,		0
72 	},
73 	{
74 		REMOTE_IP1,	7000,		PUB_IP1,	53472,
75 		NPF_NATOUT,	IFNAME_EXT,	PFIL_IN,
76 		RESULT_PASS,	LOCAL_IP1,	15000
77 	},
78 
79 	/*
80 	 * NAT redirect (inbound NAT):
81 	 *	map $ext_if dynamic $local_ip1 port 8000 <- $pub_ip1 port 8000
82 	 */
83 	{
84 		REMOTE_IP2,	16000,		PUB_IP1,	8000,
85 		NPF_NATIN,	IFNAME_EXT,	PFIL_IN,
86 		RESULT_PASS,	LOCAL_IP1,	6000
87 	},
88 	{
89 		LOCAL_IP1,	6000,		REMOTE_IP2,	16000,
90 		NPF_NATIN,	IFNAME_EXT,	PFIL_OUT,
91 		RESULT_PASS,	PUB_IP1,	8000
92 	},
93 
94 	/*
95 	 * Bi-directional NAT (inbound + outbound NAT):
96 	 *	map $ext_if dynamic $local_ip2 <-> $pub_ip2
97 	 */
98 	{
99 		REMOTE_IP2,	17000,		PUB_IP2,	9000,
100 		NPF_BINAT,	IFNAME_EXT,	PFIL_IN,
101 		RESULT_PASS,	LOCAL_IP2,	9000
102 	},
103 	{
104 		LOCAL_IP2,	9000,		REMOTE_IP2,	17000,
105 		NPF_BINAT,	IFNAME_EXT,	PFIL_OUT,
106 		RESULT_PASS,	PUB_IP2,	9000
107 	},
108 	{
109 		LOCAL_IP2,	18000,		REMOTE_IP2,	9000,
110 		NPF_BINAT,	IFNAME_EXT,	PFIL_OUT,
111 		RESULT_PASS,	PUB_IP2,	18000
112 	},
113 	{
114 		REMOTE_IP2,	9000,		PUB_IP2,	18000,
115 		NPF_BINAT,	IFNAME_EXT,	PFIL_IN,
116 		RESULT_PASS,	LOCAL_IP2,	18000
117 	},
118 
119 };
120 
121 static bool
122 nmatch_addr(const char *saddr, const struct in_addr *addr2)
123 {
124 	const in_addr_t addr1 = inet_addr(saddr);
125 	return memcmp(&addr1, &addr2->s_addr, sizeof(in_addr_t)) != 0;
126 }
127 
128 static bool
129 checkresult(bool verbose, unsigned i, struct mbuf *m, ifnet_t *ifp, int error)
130 {
131 	const struct test_case *t = &test_cases[i];
132 	npf_cache_t npc = { .npc_info = 0 };
133 	nbuf_t nbuf;
134 
135 	if (verbose) {
136 		printf("packet %d (expected %d ret %d)\n", i+1, t->ret, error);
137 	}
138 	if (error) {
139 		return error == t->ret;
140 	}
141 
142 	nbuf_init(&nbuf, m, ifp);
143 	if (!npf_cache_all(&npc, &nbuf)) {
144 		printf("error: could not fetch the packet data");
145 		return false;
146 	}
147 
148 	const struct ip *ip = npc.npc_ip.v4;
149 	const struct udphdr *uh = npc.npc_l4.udp;
150 
151 	if (verbose) {
152 		printf("\tpost-translation: src %s (%d)",
153 		    inet_ntoa(ip->ip_src), ntohs(uh->uh_sport));
154 		printf(" dst %s (%d)\n",
155 		    inet_ntoa(ip->ip_dst), ntohs(uh->uh_dport));
156 	}
157 
158 	const bool forw = t->di == PFIL_OUT;
159 	const char *saddr = forw ? t->taddr : t->src;
160 	const char *daddr = forw ? t->dst : t->taddr;
161 	in_addr_t sport = forw ? t->tport : t->sport;
162 	in_addr_t dport = forw ? t->dport : t->tport;
163 
164 	bool defect = false;
165 	defect |= nmatch_addr(saddr, &ip->ip_src);
166 	defect |= sport != ntohs(uh->uh_sport);
167 	defect |= nmatch_addr(daddr, &ip->ip_dst);
168 	defect |= dport != ntohs(uh->uh_dport);
169 
170 	return !defect && error == t->ret;
171 }
172 
173 static struct mbuf *
174 fill_packet(const struct test_case *t)
175 {
176 	struct mbuf *m;
177 	struct ip *ip;
178 	struct udphdr *uh;
179 
180 	m = mbuf_construct(IPPROTO_UDP);
181 	uh = mbuf_return_hdrs(m, false, &ip);
182 	ip->ip_src.s_addr = inet_addr(t->src);
183 	ip->ip_dst.s_addr = inet_addr(t->dst);
184 	uh->uh_sport = htons(t->sport);
185 	uh->uh_dport = htons(t->dport);
186 	return m;
187 }
188 
189 bool
190 npf_nat_test(bool verbose)
191 {
192 	for (unsigned i = 0; i < __arraycount(test_cases); i++) {
193 		const struct test_case *t = &test_cases[i];
194 		ifnet_t *ifp = ifunit(t->ifname);
195 		struct mbuf *m = fill_packet(t);
196 		int error;
197 		bool ret;
198 
199 		if (ifp == NULL) {
200 			printf("Interface %s is not configured.\n", t->ifname);
201 			return false;
202 		}
203 		error = npf_packet_handler(NULL, &m, ifp, t->di);
204 		ret = checkresult(verbose, i, m, ifp, error);
205 		if (m) {
206 			m_freem(m);
207 		}
208 		if (!ret) {
209 			return false;
210 		}
211 	}
212 	return true;
213 }
214