xref: /netbsd-src/sys/netatalk/ddp_input.c (revision f9fd253c05a1a6b48d8dba8c788882fddd899b60)
1 /*	$NetBSD: ddp_input.c,v 1.34 2023/03/30 11:21:08 riastradh Exp $	 */
2 
3 /*
4  * Copyright (c) 1990,1994 Regents of The University of Michigan.
5  * All Rights Reserved.
6  *
7  * Permission to use, copy, modify, and distribute this software and
8  * its documentation for any purpose and without fee is hereby granted,
9  * provided that the above copyright notice appears in all copies and
10  * that both that copyright notice and this permission notice appear
11  * in supporting documentation, and that the name of The University
12  * of Michigan not be used in advertising or publicity pertaining to
13  * distribution of the software without specific, written prior
14  * permission. This software is supplied as is without expressed or
15  * implied warranties of any kind.
16  *
17  * This product includes software developed by the University of
18  * California, Berkeley and its contributors.
19  *
20  *	Research Systems Unix Group
21  *	The University of Michigan
22  *	c/o Wesley Craig
23  *	535 W. William Street
24  *	Ann Arbor, Michigan
25  *	+1-313-764-2278
26  *	netatalk@umich.edu
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: ddp_input.c,v 1.34 2023/03/30 11:21:08 riastradh Exp $");
31 #include "opt_atalk.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/mbuf.h>
37 #include <sys/socket.h>
38 #include <sys/socketvar.h>
39 #include <sys/syslog.h>
40 #include <net/if.h>
41 #include <net/route.h>
42 #include <net/if_ether.h>
43 #include <netinet/in.h>
44 
45 #include <netatalk/at.h>
46 #include <netatalk/at_var.h>
47 #include <netatalk/ddp.h>
48 #include <netatalk/ddp_var.h>
49 #include <netatalk/ddp_private.h>
50 #include <netatalk/at_extern.h>
51 
52 int             ddp_forward = 1;
53 int             ddp_firewall = 0;
54 extern int      ddp_cksum;
55 void            ddp_input(struct mbuf *, struct ifnet *, struct elaphdr *, int);
56 
57 static struct at_ifaddr *
at_ifaddr_for_ifp(struct ifnet * const ifp,int phase_flag)58 at_ifaddr_for_ifp(struct ifnet * const ifp, int phase_flag)
59 {
60 	struct at_ifaddr *aa;
61 
62 	TAILQ_FOREACH(aa, &at_ifaddr, aa_list) {
63 		if (aa->aa_ifp == ifp &&
64 		    (aa->aa_flags & AFA_PHASE2) == phase_flag) {
65 			return aa;
66 		}
67 	}
68 	return NULL;
69 }
70 
71 void
atintr2(void * arg __unused)72 atintr2(void *arg __unused)
73 {
74 	struct mbuf *m;
75 
76 	mutex_enter(softnet_lock);
77 	while ((m = pktq_dequeue(at_pktq2)) != NULL) {
78 		struct ifnet *ifp;
79 
80 		m_claimm(m, &atalk_rx_mowner);
81 		ifp = m_get_rcvif_NOMPSAFE(m);
82 		if (at_ifaddr_for_ifp(ifp, AFA_PHASE2) == NULL) {
83 			/* ifp not an appletalk interface */
84 			m_freem(m);
85 			continue;
86 		}
87 		ddp_input(m, ifp, NULL, 2);
88 	}
89 	mutex_exit(softnet_lock);
90 }
91 
92 void
atintr1(void * arg __unused)93 atintr1(void *arg __unused)
94 {
95 	struct mbuf *m;
96 
97 	mutex_enter(softnet_lock);
98 	while ((m = pktq_dequeue(at_pktq1)) != NULL) {
99 		struct ifnet *ifp;
100 		struct elaphdr *elhp, elh;
101 
102 		m_claimm(m, &atalk_rx_mowner);
103 		ifp = m_get_rcvif_NOMPSAFE(m);
104 		if (at_ifaddr_for_ifp(ifp, 0) == NULL) {
105 			/* ifp not an appletalk interface */
106 			m_freem(m);
107 			continue;
108 		}
109 		if (m->m_len < SZ_ELAPHDR &&
110 		    ((m = m_pullup(m, SZ_ELAPHDR)) == 0)) {
111 			DDP_STATINC(DDP_STAT_TOOSHORT);
112 			continue;
113 		}
114 		elhp = mtod(m, struct elaphdr *);
115 		m_adj(m, SZ_ELAPHDR);
116 
117 		if (elhp->el_type == ELAP_DDPEXTEND) {
118 			ddp_input(m, ifp, NULL, 1);
119 		} else {
120 			memcpy((void *) & elh, (void *) elhp, SZ_ELAPHDR);
121 			ddp_input(m, ifp, &elh, 1);
122 		}
123 	}
124 	mutex_exit(softnet_lock);
125 }
126 
127 struct route    forwro;
128 
129 void
ddp_input(struct mbuf * m,struct ifnet * ifp,struct elaphdr * elh,int phase)130 ddp_input(struct mbuf *m, struct ifnet *ifp, struct elaphdr *elh, int phase)
131 {
132 	struct rtentry *rt;
133 	struct sockaddr_at from, to;
134 	struct ddpshdr *dsh, ddps;
135 	struct at_ifaddr *aa;
136 	struct ddpehdr *deh = NULL, ddpe;
137 	struct ddpcb   *ddp;
138 	int             dlen, mlen;
139 	u_short         cksum = 0;
140 	union {
141 		struct sockaddr		dst;
142 		struct sockaddr_at	dsta;
143 	} u;
144 
145 	memset((void *) & from, 0, sizeof(struct sockaddr_at));
146 	if (elh) {
147 		DDP_STATINC(DDP_STAT_SHORT);
148 
149 		if (m->m_len < sizeof(struct ddpshdr) &&
150 		    ((m = m_pullup(m, sizeof(struct ddpshdr))) == 0)) {
151 			DDP_STATINC(DDP_STAT_TOOSHORT);
152 			return;
153 		}
154 		dsh = mtod(m, struct ddpshdr *);
155 		memcpy((void *) & ddps, (void *) dsh, sizeof(struct ddpshdr));
156 		ddps.dsh_bytes = ntohl(ddps.dsh_bytes);
157 		dlen = ddps.dsh_len;
158 
159 		to.sat_addr.s_net = ATADDR_ANYNET;
160 		to.sat_addr.s_node = elh->el_dnode;
161 		to.sat_port = ddps.dsh_dport;
162 		from.sat_addr.s_net = ATADDR_ANYNET;
163 		from.sat_addr.s_node = elh->el_snode;
164 		from.sat_port = ddps.dsh_sport;
165 
166 		TAILQ_FOREACH(aa, &at_ifaddr, aa_list) {
167 			if (aa->aa_ifp == ifp &&
168 			    (aa->aa_flags & AFA_PHASE2) == 0 &&
169 			    (AA_SAT(aa)->sat_addr.s_node ==
170 			     to.sat_addr.s_node ||
171 			     to.sat_addr.s_node == ATADDR_BCAST))
172 				break;
173 		}
174 		if (aa == NULL) {
175 			m_freem(m);
176 			return;
177 		}
178 	} else {
179 		DDP_STATINC(DDP_STAT_LONG);
180 
181 		if (m->m_len < sizeof(struct ddpehdr) &&
182 		    ((m = m_pullup(m, sizeof(struct ddpehdr))) == 0)) {
183 			DDP_STATINC(DDP_STAT_TOOSHORT);
184 			return;
185 		}
186 		deh = mtod(m, struct ddpehdr *);
187 		memcpy((void *) & ddpe, (void *) deh, sizeof(struct ddpehdr));
188 		ddpe.deh_bytes = ntohl(ddpe.deh_bytes);
189 		dlen = ddpe.deh_len;
190 
191 		if ((cksum = ddpe.deh_sum) == 0) {
192 			DDP_STATINC(DDP_STAT_NOSUM);
193 		}
194 		from.sat_addr.s_net = ddpe.deh_snet;
195 		from.sat_addr.s_node = ddpe.deh_snode;
196 		from.sat_port = ddpe.deh_sport;
197 		to.sat_addr.s_net = ddpe.deh_dnet;
198 		to.sat_addr.s_node = ddpe.deh_dnode;
199 		to.sat_port = ddpe.deh_dport;
200 
201 		if (to.sat_addr.s_net == ATADDR_ANYNET) {
202 			TAILQ_FOREACH(aa, &at_ifaddr, aa_list) {
203 				if (phase == 1 && (aa->aa_flags & AFA_PHASE2))
204 					continue;
205 
206 				if (phase == 2 &&
207 				    (aa->aa_flags & AFA_PHASE2) == 0)
208 					continue;
209 
210 				if (aa->aa_ifp == ifp &&
211 				    (AA_SAT(aa)->sat_addr.s_node ==
212 				     to.sat_addr.s_node ||
213 				     to.sat_addr.s_node == ATADDR_BCAST ||
214 				     (ifp->if_flags & IFF_LOOPBACK)))
215 					break;
216 			}
217 		} else {
218 			TAILQ_FOREACH(aa, &at_ifaddr, aa_list) {
219 				if (to.sat_addr.s_net == aa->aa_firstnet &&
220 				    to.sat_addr.s_node == 0)
221 					break;
222 
223 				if ((ntohs(to.sat_addr.s_net) <
224 				     ntohs(aa->aa_firstnet) ||
225 				     ntohs(to.sat_addr.s_net) >
226 				     ntohs(aa->aa_lastnet)) &&
227 				    (ntohs(to.sat_addr.s_net) < 0xff00 ||
228 				     ntohs(to.sat_addr.s_net) > 0xfffe))
229 					continue;
230 
231 				if (to.sat_addr.s_node !=
232 				    AA_SAT(aa)->sat_addr.s_node &&
233 				    to.sat_addr.s_node != ATADDR_BCAST)
234 					continue;
235 
236 				break;
237 			}
238 		}
239 	}
240 
241 	/*
242          * Adjust the length, removing any padding that may have been added
243          * at a link layer.  We do this before we attempt to forward a packet,
244          * possibly on a different media.
245          */
246 	mlen = m->m_pkthdr.len;
247 	if (mlen < dlen) {
248 		DDP_STATINC(DDP_STAT_TOOSMALL);
249 		m_freem(m);
250 		return;
251 	}
252 	if (mlen > dlen) {
253 		m_adj(m, dlen - mlen);
254 	}
255 	/*
256          * XXX Should we deliver broadcasts locally, also, or rely on the
257          * link layer to give us a copy?  For the moment, the latter.
258          */
259 	if (aa == NULL || (to.sat_addr.s_node == ATADDR_BCAST &&
260 		aa->aa_ifp != ifp && (ifp->if_flags & IFF_LOOPBACK) == 0)) {
261 		if (ddp_forward == 0) {
262 			m_freem(m);
263 			return;
264 		}
265 		sockaddr_at_init(&u.dsta, &to.sat_addr, 0);
266 		rt = rtcache_lookup(&forwro, &u.dst);
267 #if 0		/* XXX The if-condition is always false.  What was this
268 		 * actually trying to test?
269 		 */
270 		if (to.sat_addr.s_net !=
271 		    satocsat(rtcache_getdst(&forwro))->sat_addr.s_net &&
272 		    ddpe.deh_hops == DDP_MAXHOPS) {
273 			m_freem(m);
274 			return;
275 		}
276 #endif
277 		if (ddp_firewall && (rt == NULL || rt->rt_ifp != ifp)) {
278 			rtcache_unref(rt, &forwro);
279 			m_freem(m);
280 			return;
281 		}
282 		rtcache_unref(rt, &forwro);
283 		ddpe.deh_hops++;
284 		ddpe.deh_bytes = htonl(ddpe.deh_bytes);
285 		memcpy((void *) deh, (void *) & ddpe, sizeof(u_short));/*XXX*/
286 		if (ddp_route(m, &forwro)) {
287 			DDP_STATINC(DDP_STAT_CANTFORWARD);
288 		} else {
289 			DDP_STATINC(DDP_STAT_FORWARD);
290 		}
291 		return;
292 	}
293 	from.sat_len = sizeof(struct sockaddr_at);
294 	from.sat_family = AF_APPLETALK;
295 
296 	if (elh) {
297 		m_adj(m, sizeof(struct ddpshdr));
298 	} else {
299 		if (ddp_cksum && cksum && cksum != at_cksum(m, sizeof(int))) {
300 			DDP_STATINC(DDP_STAT_BADSUM);
301 			m_freem(m);
302 			return;
303 		}
304 		m_adj(m, sizeof(struct ddpehdr));
305 	}
306 
307 	if ((ddp = ddp_search(&from, &to, aa)) == NULL) {
308 		m_freem(m);
309 		return;
310 	}
311 	if (sbappendaddr(&ddp->ddp_socket->so_rcv, (struct sockaddr *) & from,
312 			 m, (struct mbuf *) 0) == 0) {
313 		DDP_STATINC(DDP_STAT_NOSOCKSPACE);
314 		soroverflow(ddp->ddp_socket);
315 		m_freem(m);
316 		return;
317 	}
318 #if IFA_STATS
319 	if (aa)
320 		aa->aa_ifa.ifa_data.ifad_inbytes += dlen;
321 #endif
322 	sorwakeup(ddp->ddp_socket);
323 }
324 
325 #if 0
326 
327 #define BPXLEN	48
328 #define BPALEN	16
329 #include <ctype.h>
330 
331 static void
332 bprint(char *data, int len)
333 {
334 	char            xout[BPXLEN], aout[BPALEN];
335 	int             i = 0;
336 
337 	memset(xout, 0, BPXLEN);
338 	memset(aout, 0, BPALEN);
339 
340 	for (;;) {
341 		if (len < 1) {
342 			if (i != 0) {
343 				printf("%s\t%s\n", xout, aout);
344 			}
345 			printf("%s\n", "(end)");
346 			break;
347 		}
348 		xout[(i * 3)] = hexdigits[(*data & 0xf0) >> 4];
349 		xout[(i * 3) + 1] = hexdigits[*data & 0x0f];
350 
351 		if ((u_char) * data < 0x7f && (u_char) * data > 0x20) {
352 			aout[i] = *data;
353 		} else {
354 			aout[i] = '.';
355 		}
356 
357 		xout[(i * 3) + 2] = ' ';
358 
359 		i++;
360 		len--;
361 		data++;
362 
363 		if (i > BPALEN - 2) {
364 			printf("%s\t%s\n", xout, aout);
365 			memset(xout, 0, BPXLEN);
366 			memset(aout, 0, BPALEN);
367 			i = 0;
368 			continue;
369 		}
370 	}
371 }
372 
373 static void
374 m_printm(struct mbuf *m)
375 {
376 	for (; m; m = m->m_next)
377 		bprint(mtod(m, char *), m->m_len);
378 }
379 #endif
380