xref: /netbsd-src/usr.sbin/npf/npftest/libnpftest/npf_test_subr.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*
2  * NPF initialisation and handler routines.
3  *
4  * Public Domain.
5  */
6 
7 #ifdef _KERNEL
8 #include <sys/types.h>
9 #include <sys/cprng.h>
10 #include <sys/kmem.h>
11 #include <net/if.h>
12 #include <net/if_types.h>
13 #endif
14 
15 #include "npf_impl.h"
16 #include "npf_test.h"
17 
18 /* State of the current stream. */
19 static npf_state_t	cstream_state;
20 static void *		cstream_ptr;
21 static bool		cstream_retval;
22 
23 static long		(*_random_func)(void);
24 static int		(*_pton_func)(int, const char *, void *);
25 static const char *	(*_ntop_func)(int, const void *, char *, socklen_t);
26 
27 static void		npf_state_sample(npf_state_t *, bool);
28 
29 static void		load_npf_config_ifs(nvlist_t *, bool);
30 
31 #ifndef __NetBSD__
32 /*
33  * Standalone NPF: we define the same struct ifnet members
34  * to reduce the npf_ifops_t implementation differences.
35  */
36 struct ifnet {
37 	char		if_xname[32];
38 	void *		if_softc;
39 	TAILQ_ENTRY(ifnet) if_list;
40 };
41 #endif
42 
43 static TAILQ_HEAD(, ifnet) npftest_ifnet_list =
44     TAILQ_HEAD_INITIALIZER(npftest_ifnet_list);
45 
46 static const char *	npftest_ifop_getname(ifnet_t *);
47 static void		npftest_ifop_flush(void *);
48 static void *		npftest_ifop_getmeta(const ifnet_t *);
49 static void		npftest_ifop_setmeta(ifnet_t *, void *);
50 
51 static const npf_ifops_t npftest_ifops = {
52 	.getname	= npftest_ifop_getname,
53 	.lookup		= npf_test_getif,
54 	.flush		= npftest_ifop_flush,
55 	.getmeta	= npftest_ifop_getmeta,
56 	.setmeta	= npftest_ifop_setmeta,
57 };
58 
59 void
60 npf_test_init(int (*pton_func)(int, const char *, void *),
61     const char *(*ntop_func)(int, const void *, char *, socklen_t),
62     long (*rndfunc)(void))
63 {
64 	npf_t *npf;
65 
66 	npf_sysinit(0);
67 	npf = npf_create(0, &npftest_mbufops, &npftest_ifops);
68 	npf_thread_register(npf);
69 	npf_setkernctx(npf);
70 
71 	npf_state_setsampler(npf_state_sample);
72 	_pton_func = pton_func;
73 	_ntop_func = ntop_func;
74 	_random_func = rndfunc;
75 }
76 
77 void
78 npf_test_fini(void)
79 {
80 	npf_t *npf = npf_getkernctx();
81 	npf_destroy(npf);
82 	npf_sysfini();
83 }
84 
85 int
86 npf_test_load(const void *buf, size_t len, bool verbose)
87 {
88 	nvlist_t *npf_dict;
89 	npf_error_t error;
90 
91 	npf_dict = nvlist_unpack(buf, len, 0);
92 	if (!npf_dict) {
93 		printf("%s: could not unpack the nvlist\n", __func__);
94 		return EINVAL;
95 	}
96 	load_npf_config_ifs(npf_dict, verbose);
97 
98 	// Note: npf_dict will be consumed by npf_load().
99 	return npf_load(npf_getkernctx(), npf_dict, &error);
100 }
101 
102 ifnet_t *
103 npf_test_addif(const char *ifname, bool reg, bool verbose)
104 {
105 	npf_t *npf = npf_getkernctx();
106 	ifnet_t *ifp = kmem_zalloc(sizeof(*ifp), KM_SLEEP);
107 
108 	/*
109 	 * This is a "fake" interface with explicitly set index.
110 	 * Note: test modules may not setup pfil(9) hooks and if_attach()
111 	 * may not trigger npf_ifmap_attach(), so we call it manually.
112 	 */
113 	strlcpy(ifp->if_xname, ifname, sizeof(ifp->if_xname));
114 	TAILQ_INSERT_TAIL(&npftest_ifnet_list, ifp, if_list);
115 
116 	npf_ifmap_attach(npf, ifp);
117 	if (reg) {
118 		npf_ifmap_register(npf, ifname);
119 	}
120 
121 	if (verbose) {
122 		printf("+ Interface %s\n", ifname);
123 	}
124 	return ifp;
125 }
126 
127 static void
128 load_npf_config_ifs(nvlist_t *npf_dict, bool verbose)
129 {
130 	const nvlist_t * const *iflist;
131 	const nvlist_t *dbg_dict;
132 	size_t nitems;
133 
134 	dbg_dict = dnvlist_get_nvlist(npf_dict, "debug", NULL);
135 	if (!dbg_dict) {
136 		return;
137 	}
138 	if (!nvlist_exists_nvlist_array(dbg_dict, "interfaces")) {
139 		return;
140 	}
141 	iflist = nvlist_get_nvlist_array(dbg_dict, "interfaces", &nitems);
142 	for (unsigned i = 0; i < nitems; i++) {
143 		const nvlist_t *ifdict = iflist[i];
144 		const char *ifname;
145 
146 		if ((ifname = nvlist_get_string(ifdict, "name")) != NULL) {
147 			(void)npf_test_addif(ifname, true, verbose);
148 		}
149 	}
150 }
151 
152 static const char *
153 npftest_ifop_getname(ifnet_t *ifp)
154 {
155 	return ifp->if_xname;
156 }
157 
158 ifnet_t *
159 npf_test_getif(const char *ifname)
160 {
161 	ifnet_t *ifp;
162 
163 	TAILQ_FOREACH(ifp, &npftest_ifnet_list, if_list) {
164 		if (!strcmp(ifp->if_xname, ifname))
165 			return ifp;
166 	}
167 	return NULL;
168 }
169 
170 static void
171 npftest_ifop_flush(void *arg)
172 {
173 	ifnet_t *ifp;
174 
175 	TAILQ_FOREACH(ifp, &npftest_ifnet_list, if_list)
176 		ifp->if_softc = arg;
177 }
178 
179 static void *
180 npftest_ifop_getmeta(const ifnet_t *ifp)
181 {
182 	return ifp->if_softc;
183 }
184 
185 static void
186 npftest_ifop_setmeta(ifnet_t *ifp, void *arg)
187 {
188 	ifp->if_softc = arg;
189 }
190 
191 /*
192  * State sampler - this routine is called from inside of NPF state engine.
193  */
194 static void
195 npf_state_sample(npf_state_t *nst, bool retval)
196 {
197 	/* Pointer will serve as an ID. */
198 	cstream_ptr = nst;
199 	memcpy(&cstream_state, nst, sizeof(npf_state_t));
200 	cstream_retval = retval;
201 }
202 
203 int
204 npf_test_statetrack(const void *data, size_t len, ifnet_t *ifp,
205     bool forw, int64_t *result)
206 {
207 	npf_t *npf = npf_getkernctx();
208 	struct mbuf *m;
209 	int i = 0, error;
210 
211 	m = mbuf_getwithdata(data, len);
212 	error = npf_packet_handler(npf, &m, ifp, forw ? PFIL_OUT : PFIL_IN);
213 	if (error) {
214 		assert(m == NULL);
215 		return error;
216 	}
217 	assert(m != NULL);
218 	m_freem(m);
219 
220 	const int di = forw ? NPF_FLOW_FORW : NPF_FLOW_BACK;
221 	npf_tcpstate_t *fstate = &cstream_state.nst_tcpst[di];
222 	npf_tcpstate_t *tstate = &cstream_state.nst_tcpst[!di];
223 
224 	result[i++] = (intptr_t)cstream_ptr;
225 	result[i++] = cstream_retval;
226 	result[i++] = cstream_state.nst_state;
227 
228 	result[i++] = fstate->nst_end;
229 	result[i++] = fstate->nst_maxend;
230 	result[i++] = fstate->nst_maxwin;
231 	result[i++] = fstate->nst_wscale;
232 
233 	result[i++] = tstate->nst_end;
234 	result[i++] = tstate->nst_maxend;
235 	result[i++] = tstate->nst_maxwin;
236 	result[i++] = tstate->nst_wscale;
237 
238 	return 0;
239 }
240 
241 int
242 npf_inet_pton(int af, const char *src, void *dst)
243 {
244 	return _pton_func(af, src, dst);
245 }
246 
247 const char *
248 npf_inet_ntop(int af, const void *src, char *dst, socklen_t size)
249 {
250 	return _ntop_func(af, src, dst, size);
251 }
252 
253 #ifdef _KERNEL
254 /*
255  * Need to override cprng_fast32() -- we need deterministic PRNG.
256  */
257 uint32_t
258 cprng_fast32(void)
259 {
260 	return (uint32_t)(_random_func ? _random_func() : random());
261 }
262 #endif
263