xref: /freebsd/sys/netinet/raw_ip.c (revision bcd92649c9952c9c9e8845dbd34276a60dd16664) 
1 /*
2  * Copyright (c) 1982, 1986, 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)raw_ip.c	8.7 (Berkeley) 5/15/95
34  *	$Id: raw_ip.c,v 1.37 1996/10/25 17:57:48 fenner Exp $
35  */
36 
37 #include <sys/param.h>
38 #include <sys/queue.h>
39 #include <sys/malloc.h>
40 #include <sys/mbuf.h>
41 #include <sys/socket.h>
42 #include <sys/protosw.h>
43 #include <sys/socketvar.h>
44 #include <sys/errno.h>
45 #include <sys/systm.h>
46 
47 #include <net/if.h>
48 #include <net/route.h>
49 
50 #define _IP_VHL
51 #include <netinet/in.h>
52 #include <netinet/in_systm.h>
53 #include <netinet/ip.h>
54 #include <netinet/in_pcb.h>
55 #include <netinet/in_var.h>
56 #include <netinet/ip_var.h>
57 #include <netinet/ip_mroute.h>
58 
59 #include <netinet/ip_fw.h>
60 
61 #if !defined(COMPAT_IPFW) || COMPAT_IPFW == 1
62 #undef COMPAT_IPFW
63 #define COMPAT_IPFW 1
64 #else
65 #undef COMPAT_IPFW
66 #endif
67 
68 static struct inpcbhead ripcb;
69 static struct inpcbinfo ripcbinfo;
70 
71 /*
72  * Nominal space allocated to a raw ip socket.
73  */
74 #define	RIPSNDQ		8192
75 #define	RIPRCVQ		8192
76 
77 /*
78  * Raw interface to IP protocol.
79  */
80 
81 /*
82  * Initialize raw connection block q.
83  */
84 void
85 rip_init()
86 {
87 	LIST_INIT(&ripcb);
88 	ripcbinfo.listhead = &ripcb;
89 	/*
90 	 * XXX We don't use the hash list for raw IP, but it's easier
91 	 * to allocate a one entry hash list than it is to check all
92 	 * over the place for hashbase == NULL.
93 	 */
94 	ripcbinfo.hashbase = phashinit(1, M_PCB, &ripcbinfo.hashsize);
95 }
96 
97 static struct	sockaddr_in ripsrc = { sizeof(ripsrc), AF_INET };
98 /*
99  * Setup generic address and protocol structures
100  * for raw_input routine, then pass them along with
101  * mbuf chain.
102  */
103 void
104 rip_input(m, iphlen)
105 	struct mbuf *m;
106 	int iphlen;
107 {
108 	register struct ip *ip = mtod(m, struct ip *);
109 	register struct inpcb *inp;
110 	struct inpcb *last = 0;
111 	struct mbuf *opts = 0;
112 
113 	ripsrc.sin_addr = ip->ip_src;
114 	for (inp = ripcb.lh_first; inp != NULL; inp = inp->inp_list.le_next) {
115 		if (inp->inp_ip.ip_p && inp->inp_ip.ip_p != ip->ip_p)
116 			continue;
117 		if (inp->inp_laddr.s_addr &&
118                   inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
119 			continue;
120 		if (inp->inp_faddr.s_addr &&
121                   inp->inp_faddr.s_addr != ip->ip_src.s_addr)
122 			continue;
123 		if (last) {
124 			struct mbuf *n = m_copy(m, 0, (int)M_COPYALL);
125 			if (n) {
126 				if (last->inp_flags & INP_CONTROLOPTS ||
127 				    last->inp_socket->so_options & SO_TIMESTAMP)
128 				    ip_savecontrol(last, &opts, ip, n);
129 				if (sbappendaddr(&last->inp_socket->so_rcv,
130 				    (struct sockaddr *)&ripsrc, n,
131 				    opts) == 0) {
132 					/* should notify about lost packet */
133 					m_freem(n);
134 					if (opts)
135 					    m_freem(opts);
136 				} else
137 					sorwakeup(last->inp_socket);
138 				opts = 0;
139 			}
140 		}
141 		last = inp;
142 	}
143 	if (last) {
144 		if (last->inp_flags & INP_CONTROLOPTS ||
145 		    last->inp_socket->so_options & SO_TIMESTAMP)
146 			ip_savecontrol(last, &opts, ip, m);
147 		if (sbappendaddr(&last->inp_socket->so_rcv,
148 		    (struct sockaddr *)&ripsrc, m, opts) == 0) {
149 			m_freem(m);
150 			if (opts)
151 			    m_freem(opts);
152 		} else
153 			sorwakeup(last->inp_socket);
154 	} else {
155 		m_freem(m);
156               ipstat.ips_noproto++;
157               ipstat.ips_delivered--;
158       }
159 }
160 
161 /*
162  * Generate IP header and pass packet to ip_output.
163  * Tack on options user may have setup with control call.
164  */
165 int
166 rip_output(m, so, dst)
167 	register struct mbuf *m;
168 	struct socket *so;
169 	u_long dst;
170 {
171 	register struct ip *ip;
172 	register struct inpcb *inp = sotoinpcb(so);
173 	int flags = (so->so_options & SO_DONTROUTE) | IP_ALLOWBROADCAST;
174 
175 	/*
176 	 * If the user handed us a complete IP packet, use it.
177 	 * Otherwise, allocate an mbuf for a header and fill it in.
178 	 */
179 	if ((inp->inp_flags & INP_HDRINCL) == 0) {
180 		if (m->m_pkthdr.len + sizeof(struct ip) > IP_MAXPACKET) {
181 			m_freem(m);
182 			return(EMSGSIZE);
183 		}
184 		M_PREPEND(m, sizeof(struct ip), M_WAIT);
185 		ip = mtod(m, struct ip *);
186 		ip->ip_tos = 0;
187 		ip->ip_off = 0;
188 		ip->ip_p = inp->inp_ip.ip_p;
189 		ip->ip_len = m->m_pkthdr.len;
190 		ip->ip_src = inp->inp_laddr;
191 		ip->ip_dst.s_addr = dst;
192 		ip->ip_ttl = MAXTTL;
193 	} else {
194 		if (m->m_pkthdr.len > IP_MAXPACKET) {
195 			m_freem(m);
196 			return(EMSGSIZE);
197 		}
198 		ip = mtod(m, struct ip *);
199 		/* don't allow both user specified and setsockopt options,
200 		   and don't allow packet length sizes that will crash */
201 		if (((IP_VHL_HL(ip->ip_vhl) != (sizeof (*ip) >> 2))
202 		     && inp->inp_options)
203 		    || (ip->ip_len > m->m_pkthdr.len)) {
204 			m_freem(m);
205 			return EINVAL;
206 		}
207 		if (ip->ip_id == 0)
208 			ip->ip_id = htons(ip_id++);
209 		/* XXX prevent ip_output from overwriting header fields */
210 		flags |= IP_RAWOUTPUT;
211 		ipstat.ips_rawout++;
212 	}
213 	return (ip_output(m, inp->inp_options, &inp->inp_route, flags,
214 			  inp->inp_moptions));
215 }
216 
217 /*
218  * Raw IP socket option processing.
219  */
220 int
221 rip_ctloutput(op, so, level, optname, m)
222 	int op;
223 	struct socket *so;
224 	int level, optname;
225 	struct mbuf **m;
226 {
227 	register struct inpcb *inp = sotoinpcb(so);
228 	register int error;
229 
230 	if (level != IPPROTO_IP) {
231 		if (op == PRCO_SETOPT && *m)
232 			(void)m_free(*m);
233 		return (EINVAL);
234 	}
235 
236 	switch (optname) {
237 
238 	case IP_HDRINCL:
239 		error = 0;
240 		if (op == PRCO_SETOPT) {
241 			if (m == 0 || *m == 0 || (*m)->m_len < sizeof (int))
242 				error = EINVAL;
243 			else if (*mtod(*m, int *))
244 				inp->inp_flags |= INP_HDRINCL;
245 			else
246 				inp->inp_flags &= ~INP_HDRINCL;
247 			if (*m)
248 				(void)m_free(*m);
249 		} else {
250 			*m = m_get(M_WAIT, MT_SOOPTS);
251 			(*m)->m_len = sizeof (int);
252 			*mtod(*m, int *) = inp->inp_flags & INP_HDRINCL;
253 		}
254 		return (error);
255 
256 #ifdef COMPAT_IPFW
257 	case IP_FW_GET:
258 		if (ip_fw_ctl_ptr == NULL || op == PRCO_SETOPT) {
259 			if (*m) (void)m_free(*m);
260 			return(EINVAL);
261 		}
262 		return (*ip_fw_ctl_ptr)(optname, m);
263 
264 	case IP_FW_ADD:
265 	case IP_FW_DEL:
266 	case IP_FW_FLUSH:
267 	case IP_FW_ZERO:
268 		if (ip_fw_ctl_ptr == NULL || op != PRCO_SETOPT) {
269 			if (*m) (void)m_free(*m);
270 			return(EINVAL);
271 		}
272 		return (*ip_fw_ctl_ptr)(optname, m);
273 
274 	case IP_NAT:
275 		if (ip_nat_ctl_ptr == NULL) {
276 			if (*m) (void)m_free(*m);
277 			return(EINVAL);
278 		}
279 		return (*ip_nat_ctl_ptr)(op, m);
280 
281 #endif
282 	case IP_RSVP_ON:
283 		return ip_rsvp_init(so);
284 		break;
285 
286 	case IP_RSVP_OFF:
287 		return ip_rsvp_done();
288 		break;
289 
290 	case IP_RSVP_VIF_ON:
291 		return ip_rsvp_vif_init(so, *m);
292 
293 	case IP_RSVP_VIF_OFF:
294 		return ip_rsvp_vif_done(so, *m);
295 
296 	case MRT_INIT:
297 	case MRT_DONE:
298 	case MRT_ADD_VIF:
299 	case MRT_DEL_VIF:
300 	case MRT_ADD_MFC:
301 	case MRT_DEL_MFC:
302 	case MRT_VERSION:
303 	case MRT_ASSERT:
304 		if (op == PRCO_SETOPT) {
305 			error = ip_mrouter_set(optname, so, *m);
306 			if (*m)
307 				(void)m_free(*m);
308 		} else if (op == PRCO_GETOPT) {
309 			error = ip_mrouter_get(optname, so, m);
310 		} else
311 			error = EINVAL;
312 		return (error);
313 	}
314 	return (ip_ctloutput(op, so, level, optname, m));
315 }
316 
317 static u_long	rip_sendspace = RIPSNDQ; /* XXX sysctl ? */
318 static u_long	rip_recvspace = RIPRCVQ; /* XXX sysctl ? */
319 
320 /*ARGSUSED*/
321 int
322 rip_usrreq(so, req, m, nam, control)
323 	register struct socket *so;
324 	int req;
325 	struct mbuf *m, *nam, *control;
326 {
327 	register int error = 0;
328 	register struct inpcb *inp = sotoinpcb(so);
329 
330 	if (req == PRU_CONTROL)
331 		return (in_control(so, (u_long)m, (caddr_t)nam,
332 			(struct ifnet *)control));
333 
334 	switch (req) {
335 
336 	case PRU_ATTACH:
337 		if (inp)
338 			panic("rip_attach");
339 		if ((so->so_state & SS_PRIV) == 0) {
340 			error = EACCES;
341 			break;
342 		}
343 		if ((error = soreserve(so, rip_sendspace, rip_recvspace)) ||
344 		    (error = in_pcballoc(so, &ripcbinfo)))
345 			break;
346 		inp = (struct inpcb *)so->so_pcb;
347 		inp->inp_ip.ip_p = (int)nam;
348 		break;
349 
350 	case PRU_DISCONNECT:
351 		if ((so->so_state & SS_ISCONNECTED) == 0) {
352 			error = ENOTCONN;
353 			break;
354 		}
355 		/* FALLTHROUGH */
356 	case PRU_ABORT:
357 		soisdisconnected(so);
358 		/* FALLTHROUGH */
359 	case PRU_DETACH:
360 		if (inp == 0)
361 			panic("rip_detach");
362 		if (so == ip_mrouter)
363 			ip_mrouter_done();
364 		ip_rsvp_force_done(so);
365 		if (so == ip_rsvpd)
366 			ip_rsvp_done();
367 		in_pcbdetach(inp);
368 		break;
369 
370 	case PRU_BIND:
371 	    {
372 		struct sockaddr_in *addr = mtod(nam, struct sockaddr_in *);
373 
374 		if (nam->m_len != sizeof(*addr)) {
375 			error = EINVAL;
376 			break;
377 		}
378 		if ((ifnet == 0) ||
379 		    ((addr->sin_family != AF_INET) &&
380 		     (addr->sin_family != AF_IMPLINK)) ||
381 		    (addr->sin_addr.s_addr &&
382 		     ifa_ifwithaddr((struct sockaddr *)addr) == 0)) {
383 			error = EADDRNOTAVAIL;
384 			break;
385 		}
386 		inp->inp_laddr = addr->sin_addr;
387 		break;
388 	    }
389 	case PRU_CONNECT:
390 	    {
391 		struct sockaddr_in *addr = mtod(nam, struct sockaddr_in *);
392 
393 		if (nam->m_len != sizeof(*addr)) {
394 			error = EINVAL;
395 			break;
396 		}
397 		if (ifnet == 0) {
398 			error = EADDRNOTAVAIL;
399 			break;
400 		}
401 		if ((addr->sin_family != AF_INET) &&
402 		     (addr->sin_family != AF_IMPLINK)) {
403 			error = EAFNOSUPPORT;
404 			break;
405 		}
406 		inp->inp_faddr = addr->sin_addr;
407 		soisconnected(so);
408 		break;
409 	    }
410 
411 	case PRU_CONNECT2:
412 		error = EOPNOTSUPP;
413 		break;
414 
415 	/*
416 	 * Mark the connection as being incapable of further input.
417 	 */
418 	case PRU_SHUTDOWN:
419 		socantsendmore(so);
420 		break;
421 
422 	/*
423 	 * Ship a packet out.  The appropriate raw output
424 	 * routine handles any massaging necessary.
425 	 */
426 	case PRU_SEND:
427 	    {
428 		register u_long dst;
429 
430 		if (so->so_state & SS_ISCONNECTED) {
431 			if (nam) {
432 				error = EISCONN;
433 				break;
434 			}
435 			dst = inp->inp_faddr.s_addr;
436 		} else {
437 			if (nam == NULL) {
438 				error = ENOTCONN;
439 				break;
440 			}
441 			dst = mtod(nam, struct sockaddr_in *)->sin_addr.s_addr;
442 		}
443 		error = rip_output(m, so, dst);
444 		m = NULL;
445 		break;
446 	    }
447 
448 	case PRU_SENSE:
449 		/*
450 		 * stat: don't bother with a blocksize.
451 		 */
452 		return (0);
453 
454 	/*
455 	 * Not supported.
456 	 */
457 	case PRU_RCVOOB:
458 	case PRU_RCVD:
459 	case PRU_LISTEN:
460 	case PRU_ACCEPT:
461 	case PRU_SENDOOB:
462 		error = EOPNOTSUPP;
463 		break;
464 
465 	case PRU_SOCKADDR:
466 		in_setsockaddr(inp, nam);
467 		break;
468 
469 	case PRU_PEERADDR:
470 		in_setpeeraddr(inp, nam);
471 		break;
472 
473 	default:
474 		panic("rip_usrreq");
475 	}
476 	if (m != NULL)
477 		m_freem(m);
478 	return (error);
479 }
480