xref: /netbsd-src/sys/netatalk/ddp_input.c (revision 4c3eb207d36f67d31994830c0a694161fc1ca39b)
1 /*	$NetBSD: ddp_input.c,v 1.33 2022/09/03 02:48:00 thorpej 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 1.33 2022/09/03 02:48:00 thorpej 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 *
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
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
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
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 		for (aa = at_ifaddr.tqh_first; aa; aa = aa->aa_list.tqe_next) {
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 			for (aa = at_ifaddr.tqh_first; aa;
203 			    aa = aa->aa_list.tqe_next) {
204 				if (phase == 1 && (aa->aa_flags & AFA_PHASE2))
205 					continue;
206 
207 				if (phase == 2 &&
208 				    (aa->aa_flags & AFA_PHASE2) == 0)
209 					continue;
210 
211 				if (aa->aa_ifp == ifp &&
212 				    (AA_SAT(aa)->sat_addr.s_node ==
213 				     to.sat_addr.s_node ||
214 				     to.sat_addr.s_node == ATADDR_BCAST ||
215 				     (ifp->if_flags & IFF_LOOPBACK)))
216 					break;
217 			}
218 		} else {
219 			for (aa = at_ifaddr.tqh_first; aa;
220 			    aa = aa->aa_list.tqe_next) {
221 				if (to.sat_addr.s_net == aa->aa_firstnet &&
222 				    to.sat_addr.s_node == 0)
223 					break;
224 
225 				if ((ntohs(to.sat_addr.s_net) <
226 				     ntohs(aa->aa_firstnet) ||
227 				     ntohs(to.sat_addr.s_net) >
228 				     ntohs(aa->aa_lastnet)) &&
229 				    (ntohs(to.sat_addr.s_net) < 0xff00 ||
230 				     ntohs(to.sat_addr.s_net) > 0xfffe))
231 					continue;
232 
233 				if (to.sat_addr.s_node !=
234 				    AA_SAT(aa)->sat_addr.s_node &&
235 				    to.sat_addr.s_node != ATADDR_BCAST)
236 					continue;
237 
238 				break;
239 			}
240 		}
241 	}
242 
243 	/*
244          * Adjust the length, removing any padding that may have been added
245          * at a link layer.  We do this before we attempt to forward a packet,
246          * possibly on a different media.
247          */
248 	mlen = m->m_pkthdr.len;
249 	if (mlen < dlen) {
250 		DDP_STATINC(DDP_STAT_TOOSMALL);
251 		m_freem(m);
252 		return;
253 	}
254 	if (mlen > dlen) {
255 		m_adj(m, dlen - mlen);
256 	}
257 	/*
258          * XXX Should we deliver broadcasts locally, also, or rely on the
259          * link layer to give us a copy?  For the moment, the latter.
260          */
261 	if (aa == NULL || (to.sat_addr.s_node == ATADDR_BCAST &&
262 		aa->aa_ifp != ifp && (ifp->if_flags & IFF_LOOPBACK) == 0)) {
263 		if (ddp_forward == 0) {
264 			m_freem(m);
265 			return;
266 		}
267 		sockaddr_at_init(&u.dsta, &to.sat_addr, 0);
268 		rt = rtcache_lookup(&forwro, &u.dst);
269 #if 0		/* XXX The if-condition is always false.  What was this
270 		 * actually trying to test?
271 		 */
272 		if (to.sat_addr.s_net !=
273 		    satocsat(rtcache_getdst(&forwro))->sat_addr.s_net &&
274 		    ddpe.deh_hops == DDP_MAXHOPS) {
275 			m_freem(m);
276 			return;
277 		}
278 #endif
279 		if (ddp_firewall && (rt == NULL || rt->rt_ifp != ifp)) {
280 			rtcache_unref(rt, &forwro);
281 			m_freem(m);
282 			return;
283 		}
284 		rtcache_unref(rt, &forwro);
285 		ddpe.deh_hops++;
286 		ddpe.deh_bytes = htonl(ddpe.deh_bytes);
287 		memcpy((void *) deh, (void *) & ddpe, sizeof(u_short));/*XXX*/
288 		if (ddp_route(m, &forwro)) {
289 			DDP_STATINC(DDP_STAT_CANTFORWARD);
290 		} else {
291 			DDP_STATINC(DDP_STAT_FORWARD);
292 		}
293 		return;
294 	}
295 	from.sat_len = sizeof(struct sockaddr_at);
296 	from.sat_family = AF_APPLETALK;
297 
298 	if (elh) {
299 		m_adj(m, sizeof(struct ddpshdr));
300 	} else {
301 		if (ddp_cksum && cksum && cksum != at_cksum(m, sizeof(int))) {
302 			DDP_STATINC(DDP_STAT_BADSUM);
303 			m_freem(m);
304 			return;
305 		}
306 		m_adj(m, sizeof(struct ddpehdr));
307 	}
308 
309 	if ((ddp = ddp_search(&from, &to, aa)) == NULL) {
310 		m_freem(m);
311 		return;
312 	}
313 	if (sbappendaddr(&ddp->ddp_socket->so_rcv, (struct sockaddr *) & from,
314 			 m, (struct mbuf *) 0) == 0) {
315 		DDP_STATINC(DDP_STAT_NOSOCKSPACE);
316 		soroverflow(ddp->ddp_socket);
317 		m_freem(m);
318 		return;
319 	}
320 #if IFA_STATS
321 	if (aa)
322 		aa->aa_ifa.ifa_data.ifad_inbytes += dlen;
323 #endif
324 	sorwakeup(ddp->ddp_socket);
325 }
326 
327 #if 0
328 
329 #define BPXLEN	48
330 #define BPALEN	16
331 #include <ctype.h>
332 
333 static void
334 bprint(char *data, int len)
335 {
336 	char            xout[BPXLEN], aout[BPALEN];
337 	int             i = 0;
338 
339 	memset(xout, 0, BPXLEN);
340 	memset(aout, 0, BPALEN);
341 
342 	for (;;) {
343 		if (len < 1) {
344 			if (i != 0) {
345 				printf("%s\t%s\n", xout, aout);
346 			}
347 			printf("%s\n", "(end)");
348 			break;
349 		}
350 		xout[(i * 3)] = hexdigits[(*data & 0xf0) >> 4];
351 		xout[(i * 3) + 1] = hexdigits[*data & 0x0f];
352 
353 		if ((u_char) * data < 0x7f && (u_char) * data > 0x20) {
354 			aout[i] = *data;
355 		} else {
356 			aout[i] = '.';
357 		}
358 
359 		xout[(i * 3) + 2] = ' ';
360 
361 		i++;
362 		len--;
363 		data++;
364 
365 		if (i > BPALEN - 2) {
366 			printf("%s\t%s\n", xout, aout);
367 			memset(xout, 0, BPXLEN);
368 			memset(aout, 0, BPALEN);
369 			i = 0;
370 			continue;
371 		}
372 	}
373 }
374 
375 static void
376 m_printm(struct mbuf *m)
377 {
378 	for (; m; m = m->m_next)
379 		bprint(mtod(m, char *), m->m_len);
380 }
381 #endif
382