xref: /csrg-svn/sys/netns/ns_ip.c (revision 25454)
1 /*
2  * Copyright (c) 1985 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)ns_ip.c	6.11 (Berkeley) 11/09/85
7  */
8 
9 /*
10  * Software interface driver for encapsulating ns in ip.
11  */
12 
13 #ifdef NSIP
14 #include "param.h"
15 #include "systm.h"
16 #include "mbuf.h"
17 #include "socket.h"
18 #include "socketvar.h"
19 #include "errno.h"
20 #include "ioctl.h"
21 #include "protosw.h"
22 
23 #include "../net/if.h"
24 #include "../net/netisr.h"
25 #include "../net/route.h"
26 
27 #include "../netinet/in.h"
28 #include "../netinet/in_systm.h"
29 #include "../netinet/in_var.h"
30 #include "../netinet/ip.h"
31 #include "../netinet/ip_var.h"
32 
33 #ifdef vax
34 #include "../vax/mtpr.h"
35 #endif
36 
37 #include "../netns/ns.h"
38 #include "../netns/ns_if.h"
39 #include "../netns/idp.h"
40 
41 #ifdef BBNNET
42 #include "../bbnnet/in_pcb.h"
43 #include "../bbnnet/nopcb.h"
44 #endif
45 
46 struct ifnet_en {
47 	struct ifnet ifen_ifnet;
48 	struct route ifen_route;
49 	struct in_addr ifen_src;
50 	struct in_addr ifen_dst;
51 };
52 
53 int	nsipoutput(), nsipioctl();
54 #define LOMTU	(1024+512);
55 
56 struct ifnet nsipif;
57 union ns_net nsip_net;
58 struct mbuf *nsip_list;		/* list of all hosts and gateways or
59 					broadcast addrs */
60 
61 struct mbuf *
62 nsipattach()
63 {
64 	register struct mbuf *m = m_getclr(M_DONTWAIT, MT_PCB);
65 	register struct ifnet *ifp;
66 
67 	if (m == NULL) return (NULL);
68 	m->m_off = MMINOFF;
69 	m->m_len = sizeof(struct ifnet_en);
70 	m->m_next = nsip_list;
71 	nsip_list = m;
72 	ifp = mtod(m, struct ifnet *);
73 
74 	ifp->if_name = "nsip";
75 	ifp->if_mtu = LOMTU;
76 	ifp->if_ioctl = nsipioctl;
77 	ifp->if_output = nsipoutput;
78 	ifp->if_flags = IFF_POINTOPOINT;
79 	ifp->if_unit = nsipif.if_unit++;
80 	if_attach(ifp);
81 	return (dtom(ifp));
82 }
83 
84 
85 /*
86  * Process an ioctl request.
87  */
88 /* ARGSUSED */
89 nsipioctl(ifp, cmd, data)
90 	register struct ifnet *ifp;
91 	int cmd;
92 	caddr_t data;
93 {
94 	int error = 0;
95 	struct ifreq *ifr;
96 
97 	switch (cmd) {
98 
99 	case SIOCSIFADDR:
100 		ifp->if_flags |= IFF_UP;
101 		/* fall into: */
102 
103 	case SIOCSIFDSTADDR:
104 		/*
105 		 * Everything else is done at a higher level.
106 		 */
107 		break;
108 
109 	case SIOCSIFFLAGS:
110 		ifr = (struct ifreq *)data;
111 		if ((ifr->ifr_flags & IFF_UP) == 0)
112 			error = nsip_free(ifp);
113 
114 
115 	default:
116 		error = EINVAL;
117 	}
118 	return (error);
119 }
120 
121 struct mbuf *nsip_badlen;
122 struct mbuf *nsip_lastin;
123 int nsip_hold_input;
124 
125 idpip_input(m, ifp)
126 	register struct mbuf *m;
127 	struct ifnet *ifp;
128 {
129 	register struct ip *ip;
130 	register struct idp *idp;
131 	register struct ifqueue *ifq = &nsintrq;
132 	int len, s;
133 
134 	if (nsip_hold_input) {
135 		if (nsip_lastin) {
136 			m_freem(nsip_lastin);
137 		}
138 		nsip_lastin = m_copy(m, 0, (int)M_COPYALL);
139 	}
140 	/*
141 	 * Get IP and IDP header together in first mbuf.
142 	 */
143 	nsipif.if_ipackets++;
144 	s = sizeof (struct ip) + sizeof (struct idp);
145 	if ((m->m_off > MMAXOFF || m->m_len < s) &&
146 	    (m = m_pullup(m, s)) == 0) {
147 		nsipif.if_ierrors++;
148 		return;
149 	}
150 	ip = mtod(m, struct ip *);
151 #ifndef	BBNNET
152 	if (ip->ip_hl > (sizeof (struct ip) >> 2)) {
153 		ip_stripoptions(ip, (struct mbuf *)0);
154 		if (m->m_len < s) {
155 			if ((m = m_pullup(m, s)) == 0) {
156 				nsipif.if_ierrors++;
157 				return;
158 			}
159 			ip = mtod(m, struct ip *);
160 		}
161 	}
162 #endif
163 
164 	/*
165 	 * Make mbuf data length reflect IDP length.
166 	 * If not enough data to reflect IDP length, drop.
167 	 */
168 	m->m_off += sizeof (struct ip);
169 	m->m_len -= sizeof (struct ip);
170 	idp = mtod(m, struct idp *);
171 	len = ntohs(idp->idp_len);
172 	if (len & 1) len++;		/* Preserve Garbage Byte */
173 	if (ip->ip_len != len) {
174 		if (len > ip->ip_len) {
175 			nsipif.if_ierrors++;
176 			if (nsip_badlen) m_freem(nsip_badlen);
177 			nsip_badlen = m;
178 			return;
179 		}
180 		/* Any extra will be trimmed off by the NS routines */
181 	}
182 
183 	/*
184 	 * Place interface pointer before the data
185 	 * for the receiving protocol.
186 	 */
187 	if (m->m_off >= MMINOFF + sizeof(struct ifnet *)) {
188 		m->m_off -= sizeof(struct ifnet *);
189 		m->m_len += sizeof(struct ifnet *);
190 	} else {
191 		struct mbuf *n;
192 
193 		n = m_get(M_DONTWAIT, MT_HEADER);
194 		if (n == (struct mbuf *)0)
195 			goto bad;
196 		n->m_off = MMINOFF;
197 		n->m_len = sizeof(struct ifnet *);
198 		n->m_next = m;
199 		m = n;
200 	}
201 	*(mtod(m, struct ifnet **)) = ifp;
202 
203 	/*
204 	 * Deliver to NS
205 	 */
206 	s = splimp();
207 	if (IF_QFULL(ifq)) {
208 		IF_DROP(ifq);
209 bad:
210 		m_freem(m);
211 		splx(s);
212 		return;
213 	}
214 	IF_ENQUEUE(ifq, m);
215 	schednetisr(NETISR_NS);
216 	splx(s);
217 	return;
218 }
219 
220 /* ARGSUSED */
221 nsipoutput(ifn, m0, dst)
222 	struct ifnet_en *ifn;
223 	struct mbuf *m0;
224 	struct sockaddr *dst;
225 {
226 
227 	register struct mbuf *m = dtom(ifn);
228 	register struct ip *ip;
229 	register struct route *ro = &(ifn->ifen_route);
230 	register int len = 0;
231 	register struct idp *idp = mtod(m0, struct idp *);
232 	int error;
233 
234 	if (m->m_len != sizeof(struct ifnet_en)) {
235 		printf("nsipoutput: bad dst ifp %x\n", ifn);
236 		goto bad;
237 	}
238 	ifn->ifen_ifnet.if_opackets++;
239 	nsipif.if_opackets++;
240 
241 
242 	/*
243 	 * Calculate data length and make space
244 	 * for IP header.
245 	 */
246 	len =  ntohs(idp->idp_len);
247 	if (len & 1) len++;		/* Preserve Garbage Byte */
248 	m = m0;
249 	if (m->m_off < MMINOFF + sizeof (struct ip)) {
250 		m = m_get(M_DONTWAIT, MT_HEADER);
251 		if (m == 0) {
252 			m_freem(m0);
253 			return (ENOBUFS);
254 		}
255 		m->m_off = MMAXOFF - sizeof (struct ip);
256 		m->m_len = sizeof (struct ip);
257 		m->m_next = m0;
258 	} else {
259 		m->m_off -= sizeof (struct ip);
260 		m->m_len += sizeof (struct ip);
261 	}
262 	/*
263 	 * Fill in IP header.
264 	 */
265 	ip = mtod(m, struct ip *);
266 	*(long *)ip = 0;
267 	ip->ip_p = IPPROTO_IDP;
268 	ip->ip_src = ifn->ifen_src;
269 	ip->ip_dst = ifn->ifen_dst;
270 #ifdef BBNNET
271 	ip->ip_tos = 0;
272 	NOPCB_IPSEND(m, len, 0, error);
273 #else
274 	ip->ip_len = (u_short)len + sizeof (struct ip);
275 	ip->ip_ttl = MAXTTL;
276 
277 	/*
278 	 * Output final datagram.
279 	 */
280 	error =  (ip_output(m, (struct mbuf *)0, ro, SO_BROADCAST));
281 #endif
282 	if (error) {
283 		ifn->ifen_ifnet.if_oerrors++;
284 		ifn->ifen_ifnet.if_ierrors = error;
285 	}
286 	return (error);
287 bad:
288 	m_freem(m0);
289 	return (ENETUNREACH);
290 }
291 
292 struct ifreq ifr = {"nsip0"};
293 
294 nsip_route(m)
295 	register struct mbuf *m;
296 {
297 	register struct nsip_req *rq = mtod(m, struct nsip_req *);
298 	struct sockaddr_ns *ns_dst = (struct sockaddr_ns *)&rq->rq_ns;
299 	struct sockaddr_in *ip_dst = (struct sockaddr_in *)&rq->rq_ip;
300 	struct route ro;
301 	struct ifnet_en *ifn;
302 	struct sockaddr_in *src;
303 
304 	/*
305 	 * First, make sure we already have an ns address:
306 	 */
307 	if (ns_hosteqnh(ns_thishost, ns_zerohost))
308 		return (EADDRNOTAVAIL);
309 	/*
310 	 * Now, determine if we can get to the destination
311 	 */
312 	bzero((caddr_t)&ro, sizeof (ro));
313 	ro.ro_dst = *(struct sockaddr *)ip_dst;
314 	rtalloc(&ro);
315 	if (ro.ro_rt == 0 || ro.ro_rt->rt_ifp == 0) {
316 		return (ENETUNREACH);
317 	}
318 
319 	/*
320 	 * And see how he's going to get back to us:
321 	 * i.e., what return ip address do we use?
322 	 */
323 	{
324 		register struct in_ifaddr *ia;
325 		struct ifnet *ifp = ro.ro_rt->rt_ifp;
326 
327 		for (ia = in_ifaddr; ia; ia = ia->ia_next)
328 			if (ia->ia_ifp == ifp)
329 				break;
330 		if (ia == 0)
331 			ia = in_ifaddr;
332 		if (ia == 0) {
333 			RTFREE(ro.ro_rt);
334 			return (EADDRNOTAVAIL);
335 		}
336 		src = (struct sockaddr_in *)&ia->ia_addr;
337 	}
338 
339 	/*
340 	 * Is there a free (pseudo-)interface or space?
341 	 */
342 	for (m = nsip_list; m; m = m->m_next) {
343 		struct ifnet *ifp = mtod(m, struct ifnet *);
344 		if ((ifp->if_flags & IFF_UP) == 0)
345 			break;
346 	}
347 	if (m == (struct mbuf *) 0)
348 		m = nsipattach();
349 	if (m == NULL) {
350 		RTFREE(ro.ro_rt);
351 		return (ENOBUFS);
352 	}
353 	ifn = mtod(m, struct ifnet_en *);
354 
355 	ifn->ifen_route = ro;
356 	ifn->ifen_dst =  ip_dst->sin_addr;
357 	ifn->ifen_src = src->sin_addr;
358 
359 	/*
360 	 * now configure this as a point to point link
361 	 */
362 	ifr.ifr_name[4] = '0' + nsipif.if_unit - 1;
363 	ifr.ifr_dstaddr = * (struct sockaddr *) ns_dst;
364 	(void)ns_control((struct socket *)0, (int)SIOCSIFDSTADDR, (caddr_t)&ifr,
365 			(struct ifnet *)ifn);
366 	satons_addr(ifr.ifr_addr).x_host = ns_thishost;
367 	return (ns_control((struct socket *)0, (int)SIOCSIFADDR, (caddr_t)&ifr,
368 			(struct ifnet *)ifn));
369 }
370 
371 nsip_free(ifp)
372 struct ifnet *ifp;
373 {
374 	register struct ifnet_en *ifn = (struct ifnet_en *)ifp;
375 	struct route *ro = & ifn->ifen_route;
376 
377 	if (ro->ro_rt) {
378 		RTFREE(ro->ro_rt);
379 		ro->ro_rt = 0;
380 	}
381 	ifp->if_flags &= ~IFF_UP;
382 	return (0);
383 }
384 
385 nsip_ctlinput(cmd, sa)
386 	int cmd;
387 	struct sockaddr *sa;
388 {
389 	extern u_char inetctlerrmap[];
390 	struct sockaddr_in *sin;
391 	int in_rtchange();
392 
393 	if ((unsigned)cmd >= PRC_NCMDS)
394 		return;
395 	if (sa->sa_family != AF_INET && sa->sa_family != AF_IMPLINK)
396 		return;
397 	sin = (struct sockaddr_in *)sa;
398 	if (sin->sin_addr.s_addr == INADDR_ANY)
399 		return;
400 
401 	switch (cmd) {
402 
403 	case PRC_ROUTEDEAD:
404 	case PRC_REDIRECT_NET:
405 	case PRC_REDIRECT_HOST:
406 	case PRC_REDIRECT_TOSNET:
407 	case PRC_REDIRECT_TOSHOST:
408 		nsip_rtchange(&sin->sin_addr);
409 		break;
410 	}
411 }
412 
413 nsip_rtchange(dst)
414 	register struct in_addr *dst;
415 {
416 	register struct mbuf *m;
417 	register struct ifnet_en *ifn;
418 
419 	for (m = nsip_list; m; m = m->m_next) {
420 		ifn = mtod(m, struct ifnet_en *);
421 		if (ifn->ifen_dst.s_addr == dst->s_addr &&
422 			ifn->ifen_route.ro_rt) {
423 				RTFREE(ifn->ifen_route.ro_rt);
424 				ifn->ifen_route.ro_rt = 0;
425 		}
426 	}
427 }
428 #endif
429