ip_icmp.c@ 15472

最後變更在這個檔案從15472是 15471,由 vboxsync 提交於 16 年前
NAT: don't try to send an ICMP package if ICMP is not available
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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	* @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94
34	* ip_icmp.c,v 1.7 1995/05/30 08:09:42 rgrimes Exp
35	*/
36
37	#include "slirp.h"
38	#include "ip_icmp.h"
39	#ifdef RT_OS_WINDOWS
40	#include <Icmpapi.h>
41	#include <Iphlpapi.h>
42	#endif
43
44
45	/* The message sent when emulating PING */
46	/* Be nice and tell them it's just a psuedo-ping packet */
47	static const char icmp_ping_msg[] = "This is a psuedo-PING packet used by Slirp to emulate ICMP ECHO-REQUEST packets.\n";
48
49	/* list of actions for icmp_error() on RX of an icmp message */
50	static const int icmp_flush[19] =
51	{
52	/* ECHO REPLY (0) */ 0,
53	1,
54	1,
55	/* DEST UNREACH (3) */ 1,
56	/* SOURCE QUENCH (4)*/ 1,
57	/* REDIRECT (5) */ 1,
58	1,
59	1,
60	/* ECHO (8) */ 0,
61	/* ROUTERADVERT (9) */ 1,
62	/* ROUTERSOLICIT (10) */ 1,
63	/* TIME EXCEEDED (11) */ 1,
64	/* PARAMETER PROBLEM (12) */ 1,
65	/* TIMESTAMP (13) */ 0,
66	/* TIMESTAMP REPLY (14) */ 0,
67	/* INFO (15) */ 0,
68	/* INFO REPLY (16) */ 0,
69	/* ADDR MASK (17) */ 0,
70	/* ADDR MASK REPLY (18) */ 0
71	};
72
73	#ifdef VBOX_WITH_SLIRP_ICMP
74	int
75	icmp_init(PNATState pData)
76	{
77	pData->icmp_socket.so_type = IPPROTO_ICMP;
78	pData->icmp_socket.so_state = SS_ISFCONNECTED;
79	#ifndef RT_OS_WINDOWS
80	# ifndef RT_OS_DARWIN
81	pData->icmp_socket.s = socket(PF_INET, SOCK_RAW, IPPROTO_ICMP);
82	# else /* !RT_OS_DARWIN */
83	pData->icmp_socket.s = socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP);
84	# endif /* RT_OS_DARWIN */
85	if (pData->icmp_socket.s == -1)
86	{
87	int rc = RTErrConvertFromErrno(errno);
88	LogRel(("NAT: ICMP/ping not available (could open ICMP socket, error %Rrc)\n", rc));
89	return 1;
90	}
91	#else /* RT_OS_WINDOWS */
92	pData->hmIcmpLibrary = LoadLibrary("Iphlpapi.dll");
93	if (pData->hmIcmpLibrary != NULL)
94	{
95	pData->pfIcmpParseReplies = (long (WINAPI )(void , long))
96	GetProcAddress(pData->hmIcmpLibrary, "IcmpParseReplies");
97	pData->pfIcmpCloseHandle = (BOOL (WINAPI *)(HANDLE))
98	GetProcAddress(pData->hmIcmpLibrary, "IcmpCloseHandle");
99	}
100	if (pData->pfIcmpParseReplies == NULL)
101	{
102	FreeLibrary(pData->hmIcmpLibrary);
103	pData->hmIcmpLibrary = LoadLibrary("Icmp.dll");
104	if (pData->hmIcmpLibrary == NULL)
105	{
106	LogRel(("NAT: Icmp.dll could not be loaded\n"));
107	return 1;
108	}
109	pData->pfIcmpParseReplies = (long (WINAPI )(void , long))
110	GetProcAddress(pData->hmIcmpLibrary, "IcmpParseReplies");
111	pData->pfIcmpCloseHandle = (BOOL (WINAPI *)(HANDLE))
112	GetProcAddress(pData->hmIcmpLibrary, "IcmpCloseHandle");
113	}
114	if (pData->pfIcmpParseReplies == NULL)
115	{
116	LogRel(("NAT: Can't find IcmpParseReplies symbol\n"));
117	FreeLibrary(pData->hmIcmpLibrary);
118	return 1;
119	}
120	if (pData->pfIcmpCloseHandle == NULL)
121	{
122	LogRel(("NAT: Can't find IcmpCloseHandle symbol\n"));
123	FreeLibrary(pData->hmIcmpLibrary);
124	return 1;
125	}
126	pData->icmp_socket.sh = IcmpCreateFile();
127	pData->phEvents[VBOX_ICMP_EVENT_INDEX] = CreateEvent(NULL, FALSE, FALSE, NULL);
128	pData->szIcmpBuffer = sizeof(ICMP_ECHO_REPLY) * 10;
129	pData->pvIcmpBuffer = malloc(pData->szIcmpBuffer);
130	#endif /* RT_OS_WINDOWS */
131	LIST_INIT(&pData->icmp_msg_head);
132	return 0;
133	}
134
135	/*
136	* ip here is ip header + 64bytes readed from ICMP packet
137	*/
138	struct icmp_msg *
139	icmp_find_original_mbuf(PNATState pData, struct ip *ip)
140	{
141	struct mbuf *m0;
142	struct ip *ip0;
143	struct icmp icp, icp0;
144	struct icmp_msg *icm = NULL;
145	int found = 0;
146	struct udphdr *udp;
147	struct tcphdr *tcp;
148	struct socket *head_socket = NULL;
149	struct socket *last_socket = NULL;
150	struct socket *so = NULL;
151	struct in_addr laddr, faddr;
152	u_short lport, fport;
153
154	laddr.s_addr = ~0;
155	faddr.s_addr = ~0;
156
157	lport = ~0;
158	fport = ~0;
159
160
161	LogRel(("%s: processing (proto:%d)\n", __FUNCTION__, ip->ip_p));
162	switch (ip->ip_p)
163	{
164	case IPPROTO_ICMP:
165	icp = (struct icmp )((char )ip + (ip->ip_hl << 2));
166	LIST_FOREACH(icm, &pData->icmp_msg_head, im_list)
167	{
168	m0 = icm->im_m;
169	ip0 = mtod(m0, struct ip *);
170	AssertRelease(ip0->ip_p == IPPROTO_ICMP);
171	icp0 = (struct icmp )((char )ip0 + (ip0->ip_hl << 2));
172	if ( ( (icp->icmp_type != ICMP_ECHO && ip->ip_src.s_addr == ip0->ip_dst.s_addr)
173	\|\| (icp->icmp_type == ICMP_ECHO && ip->ip_dst.s_addr == ip0->ip_dst.s_addr))
174	&& icp->icmp_id == icp0->icmp_id
175	&& icp->icmp_seq == icp0->icmp_seq)
176	{
177	found = 1;
178	break;
179	}
180	LogRel(("Have found nothing\n"));
181	}
182	break;
183
184	/*
185	* for TCP and UDP logic little bit reverted, we try to find the HOST socket
186	* from which the IP package has been sent.
187	*/
188	case IPPROTO_UDP:
189	head_socket = &udb;
190	udp = (struct udphdr )((char )ip + (ip->ip_hl << 2));
191	faddr.s_addr = ip->ip_dst.s_addr;
192	fport = udp->uh_dport;
193	laddr.s_addr = ip->ip_src.s_addr;
194	lport = udp->uh_sport;
195	last_socket = udp_last_so;
196	/* fall through */
197
198	case IPPROTO_TCP:
199	if (head_socket == NULL)
200	{
201	tcp = (struct tcphdr )((char )ip + (ip->ip_hl << 2));
202	head_socket = &tcb; /* head_socket could be initialized with udb*/
203	faddr.s_addr = ip->ip_dst.s_addr;
204	fport = tcp->th_dport;
205	laddr.s_addr = ip->ip_src.s_addr;
206	lport = tcp->th_sport;
207	last_socket = tcp_last_so;
208	}
209	/* check last socket first */
210	if ( last_socket->so_faddr.s_addr == faddr.s_addr
211	&& last_socket->so_fport == fport
212	&& last_socket->so_hlport == lport)
213	{
214	found = 1;
215	so = last_socket;
216	goto sofound;
217	}
218	for (so = head_socket->so_prev; so != head_socket; so = so->so_prev)
219	{
220	/* Should be reaplaced by hash here */
221	LogRel(("trying:%R[natsock] against %R[IP4]:%d lport=%d hlport=%d\n", so, &faddr, fport, lport, so->so_hlport));
222	if ( so->so_faddr.s_addr == faddr.s_addr
223	&& so->so_fport == fport
224	&& so->so_hlport == lport)
225	{
226	found = 1;
227	break;
228	}
229	}
230	break;
231
232	default:
233	LogRel(("%s:ICMP: unsupported protocol(%d)\n", __FUNCTION__, ip->ip_p));
234	}
235	sofound:
236	if (found == 1 && icm == NULL)
237	{
238	icm = malloc(sizeof(struct icmp_msg));
239	icm->im_m = so->so_m;
240	icm->im_so = so;
241	found = 1;
242	LogRel(("hit:%R[natsock]\n", so));
243	/*XXX: this storage not very long,
244	* better add flag if it should removed from lis
245	*/
246	LIST_INSERT_HEAD(&pData->icmp_msg_head, icm, im_list);
247	return (icm);
248	}
249	if (found == 1)
250	return icm;
251
252	return NULL;
253	}
254
255	static int
256	icmp_attach(PNATState pData, struct mbuf *m)
257	{
258	struct icmp_msg *icm;
259	struct ip *ip;
260	ip = mtod(m, struct ip *);
261	Assert(ip->ip_p == IPPROTO_ICMP);
262	icm = malloc(sizeof(struct icmp_msg));
263	icm->im_m = m;
264	LIST_INSERT_HEAD(&pData->icmp_msg_head, icm, im_list);
265	return 0;
266	}
267	#endif /* VBOX_WITH_SLIRP_ICMP */
268
269	/*
270	* Process a received ICMP message.
271	*/
272	void
273	icmp_input(PNATState pData, struct mbuf *m, int hlen)
274	{
275	register struct icmp *icp;
276	register struct ip ip = mtod(m, struct ip );
277	int icmplen = ip->ip_len;
278	int status;
279	uint32_t dst;
280	int ttl;
281
282	/* int code; */
283
284	DEBUG_CALL("icmp_input");
285	DEBUG_ARG("m = %lx", (long )m);
286	DEBUG_ARG("m_len = %d", m->m_len);
287
288	icmpstat.icps_received++;
289
290	/*
291	* Locate icmp structure in mbuf, and check
292	* that its not corrupted and of at least minimum length.
293	*/
294	if (icmplen < ICMP_MINLEN)
295	{
296	/* min 8 bytes payload */
297	icmpstat.icps_tooshort++;
298	freeit:
299	m_freem(pData, m);
300	goto end_error;
301	}
302
303	m->m_len -= hlen;
304	m->m_data += hlen;
305	icp = mtod(m, struct icmp *);
306	if (cksum(m, icmplen))
307	{
308	icmpstat.icps_checksum++;
309	goto freeit;
310	}
311	m->m_len += hlen;
312	m->m_data -= hlen;
313
314	/* icmpstat.icps_inhist[icp->icmp_type]++; */
315	/* code = icp->icmp_code; */
316
317	DEBUG_ARG("icmp_type = %d", icp->icmp_type);
318	switch (icp->icmp_type)
319	{
320	case ICMP_ECHO:
321	#ifndef VBOX_WITH_SLIRP_ICMP
322	icp->icmp_type = ICMP_ECHOREPLY;
323	#endif /* !VBOX_WITH_SLIRP_ICMP */
324
325	ip->ip_len += hlen; /* since ip_input subtracts this */
326	dst = ip->ip_dst.s_addr;
327	if (dst == alias_addr.s_addr)
328	{
329	#ifdef VBOX_WITH_SLIRP_ICMP
330	icp->icmp_type = ICMP_ECHOREPLY;
331	ip->ip_dst.s_addr = ip->ip_src.s_addr;
332	ip->ip_src.s_addr = dst;
333	#endif /* VBOX_WITH_SLIRP_ICMP */
334	icmp_reflect(pData, m);
335	}
336	else
337	{
338	struct socket *so;
339	struct sockaddr_in addr;
340	#ifndef VBOX_WITH_SLIRP_ICMP
341	if ((so = socreate()) == NULL)
342	goto freeit;
343	if (udp_attach(pData, so) == -1)
344	{
345	DEBUG_MISC((dfd,"icmp_input udp_attach errno = %d-%s\n",
346	errno,strerror(errno)));
347	sofree(pData, so);
348	m_free(pData, m);
349	goto end_error;
350	}
351	so->so_m = m;
352	so->so_faddr = ip->ip_dst;
353	so->so_fport = htons(7);
354	so->so_laddr = ip->ip_src;
355	so->so_lport = htons(9);
356	so->so_iptos = ip->ip_tos;
357	so->so_type = IPPROTO_ICMP;
358	so->so_state = SS_ISFCONNECTED;
359
360	addr.sin_family = AF_INET;
361	if ((so->so_faddr.s_addr & htonl(pData->netmask)) == special_addr.s_addr)
362	{
363	/* It's an alias */
364	switch (ntohl(so->so_faddr.s_addr) & ~pData->netmask)
365	{
366	case CTL_DNS:
367	addr.sin_addr = dns_addr;
368	break;
369	case CTL_ALIAS:
370	default:
371	addr.sin_addr = loopback_addr;
372	break;
373	}
374	}
375	else
376	addr.sin_addr = so->so_faddr;
377	addr.sin_port = so->so_fport;
378	if (sendto(so->s, icmp_ping_msg, strlen(icmp_ping_msg), 0,
379	(struct sockaddr *)&addr, sizeof(addr)) == -1)
380	{
381	DEBUG_MISC((dfd,"icmp_input udp sendto tx errno = %d-%s\n",
382	errno,strerror(errno)));
383	icmp_error(pData, m, ICMP_UNREACH,ICMP_UNREACH_NET, 0,strerror(errno));
384	udp_detach(pData, so);
385	}
386	#else /* VBOX_WITH_SLIRP_ICMP */
387	# ifdef RT_OS_WINDOWS
388	IP_OPTION_INFORMATION ipopt;
389	int error;
390	# endif
391	addr.sin_family = AF_INET;
392	if ((ip->ip_dst.s_addr & htonl(pData->netmask)) == special_addr.s_addr)
393	{
394	/* It's an alias */
395	switch (ntohl(ip->ip_dst.s_addr) & ~pData->netmask)
396	{
397	case CTL_DNS:
398	addr.sin_addr = dns_addr;
399	break;
400	case CTL_ALIAS:
401	default:
402	addr.sin_addr = loopback_addr;
403	break;
404	}
405	}
406	else
407	addr.sin_addr.s_addr = ip->ip_dst.s_addr;
408	# ifndef RT_OS_WINDOWS
409	if (pData->icmp_socket.s != -1)
410	{
411	icmp_attach(pData, m);
412	ttl = ip->ip_ttl;
413	LogRel(("NAT/ICMP: try to set TTL(%d)\n", ttl));
414	status = setsockopt(pData->icmp_socket.s, IPPROTO_IP, IP_TTL,
415	(void *)&ttl, sizeof(ttl));
416	if (status < 0)
417	LogRel(("NAT: Error (%s) occurred while setting TTL attribute of IP packet\n",
418	strerror(errno)));
419	if (sendto(pData->icmp_socket.s, icp, icmplen, 0,
420	(struct sockaddr *)&addr, sizeof(addr)) == -1)
421	{
422	DEBUG_MISC((dfd,"icmp_input udp sendto tx errno = %d-%s\n",
423	errno, strerror(errno)));
424	icmp_error(pData, m, ICMP_UNREACH,ICMP_UNREACH_NET, 0, strerror(errno));
425	m_free(pData, m);
426	}
427	}
428	# else /* RT_OS_WINDOWS */
429	icmp_attach(pData, m);
430	pData->icmp_socket.so_laddr.s_addr = ip->ip_src.s_addr; /* XXX: hack*/
431	pData->icmp_socket.so_icmp_id = icp->icmp_id;
432	pData->icmp_socket.so_icmp_seq = icp->icmp_seq;
433	memset(&ipopt, 0, sizeof(IP_OPTION_INFORMATION));
434	ipopt.Ttl = ip->ip_ttl;
435	status = IcmpSendEcho2(pData->icmp_socket.sh, pData->phEvents[VBOX_ICMP_EVENT_INDEX],
436	NULL, NULL, addr.sin_addr.s_addr, icp->icmp_data,
437	icmplen - offsetof(struct icmp, icmp_data) , &ipopt,
438	pData->pvIcmpBuffer, pData->szIcmpBuffer, 1);
439	if (status == 0 && (error = GetLastError()) != ERROR_IO_PENDING)
440	{
441	error = GetLastError();
442	LogRel(("NAT: Error (%d) occurred while sending ICMP (", error));
443	switch (error)
444	{
445	case ERROR_INVALID_PARAMETER:
446	LogRel(("icmp_socket:%lx is invalid)\n", pData->icmp_socket.s));
447	break;
448	case ERROR_NOT_SUPPORTED:
449	LogRel(("operation is unsupported)\n"));
450	break;
451	case ERROR_NOT_ENOUGH_MEMORY:
452	LogRel(("OOM!!!)\n"));
453	break;
454	case IP_BUF_TOO_SMALL:
455	LogRel(("Buffer too small)\n"));
456	break;
457	default:
458	LogRel(("Other error!!!)\n"));
459	break;
460	}
461	}
462	# endif /* RT_OS_WINDOWS */
463	#endif /* VBOX_WITH_SLIRP_ICMP */
464	} /* if ip->ip_dst.s_addr == alias_addr.s_addr */
465	break;
466	case ICMP_UNREACH:
467	/* XXX? report error? close socket? */
468	case ICMP_TIMXCEED:
469	case ICMP_PARAMPROB:
470	case ICMP_SOURCEQUENCH:
471	case ICMP_TSTAMP:
472	case ICMP_MASKREQ:
473	case ICMP_REDIRECT:
474	icmpstat.icps_notsupp++;
475	m_freem(pData, m);
476	break;
477
478	default:
479	icmpstat.icps_badtype++;
480	m_freem(pData, m);
481	} /* switch */
482
483	end_error:
484	/* m is m_free()'d xor put in a socket xor or given to ip_send */
485	;
486	}
487
488
489	/*
490	* Send an ICMP message in response to a situation
491	*
492	* RFC 1122: 3.2.2 MUST send at least the IP header and 8 bytes of header. MAY send more (we do).
493	* MUST NOT change this header information.
494	* MUST NOT reply to a multicast/broadcast IP address.
495	* MUST NOT reply to a multicast/broadcast MAC address.
496	* MUST reply to only the first fragment.
497	*/
498	/*
499	* Send ICMP_UNREACH back to the source regarding msrc.
500	* mbuf *msrc is used as a template, but is NOT m_free()'d.
501	* It is reported as the bad ip packet. The header should
502	* be fully correct and in host byte order.
503	* ICMP fragmentation is illegal. All machines must accept 576 bytes in one
504	* packet. The maximum payload is 576-20(ip hdr)-8(icmp hdr)=548
505	*/
506
507	#define ICMP_MAXDATALEN (IP_MSS-28)
508	void icmp_error(PNATState pData, struct mbuf msrc, u_char type, u_char code, int minsize, const char message)
509	{
510	unsigned hlen, shlen, s_ip_len;
511	register struct ip *ip;
512	register struct icmp *icp;
513	register struct mbuf *m;
514
515	DEBUG_CALL("icmp_error");
516	DEBUG_ARG("msrc = %lx", (long )msrc);
517	DEBUG_ARG("msrc_len = %d", msrc->m_len);
518
519	if (type!=ICMP_UNREACH && type!=ICMP_TIMXCEED)
520	goto end_error;
521
522	/* check msrc */
523	if (!msrc)
524	goto end_error;
525
526	ip = mtod(msrc, struct ip *);
527	#if DEBUG
528	{
529	char bufa[20], bufb[20];
530	strcpy(bufa, inet_ntoa(ip->ip_src));
531	strcpy(bufb, inet_ntoa(ip->ip_dst));
532	DEBUG_MISC((dfd, " %.16s to %.16s\n", bufa, bufb));
533	}
534	#endif
535	if (ip->ip_off & IP_OFFMASK)
536	goto end_error; /* Only reply to fragment 0 */
537
538	shlen = ip->ip_hl << 2;
539	s_ip_len = ip->ip_len;
540	if (ip->ip_p == IPPROTO_ICMP)
541	{
542	icp = (struct icmp )((char )ip + shlen);
543	/*
544	* Assume any unknown ICMP type is an error. This isn't
545	* specified by the RFC, but think about it..
546	*/
547	if (icp->icmp_type>18 \|\| icmp_flush[icp->icmp_type])
548	goto end_error;
549	}
550
551	/* make a copy */
552	if (!(m = m_get(pData)))
553	goto end_error; /* get mbuf */
554	{
555	int new_m_size;
556	new_m_size = sizeof(struct ip) + ICMP_MINLEN + msrc->m_len + ICMP_MAXDATALEN;
557	if (new_m_size>m->m_size)
558	m_inc(m, new_m_size);
559	}
560	memcpy(m->m_data, msrc->m_data, msrc->m_len);
561	m->m_len = msrc->m_len; /* copy msrc to m */
562
563	/* make the header of the reply packet */
564	ip = mtod(m, struct ip *);
565	hlen = sizeof(struct ip ); /* no options in reply */
566
567	/* fill in icmp */
568	m->m_data += hlen;
569	m->m_len -= hlen;
570
571	icp = mtod(m, struct icmp *);
572
573	if (minsize)
574	s_ip_len = shlen+ICMP_MINLEN; /* return header+8b only */
575	else if (s_ip_len > ICMP_MAXDATALEN) /* maximum size */
576	s_ip_len = ICMP_MAXDATALEN;
577
578	m->m_len = ICMP_MINLEN + s_ip_len; /* 8 bytes ICMP header */
579
580	/* min. size = 8+sizeof(struct ip)+8 */
581
582	icp->icmp_type = type;
583	icp->icmp_code = code;
584	icp->icmp_id = 0;
585	icp->icmp_seq = 0;
586
587	memcpy(&icp->icmp_ip, msrc->m_data, s_ip_len); /* report the ip packet */
588	HTONS(icp->icmp_ip.ip_len);
589	HTONS(icp->icmp_ip.ip_id);
590	HTONS(icp->icmp_ip.ip_off);
591
592	#if DEBUG
593	if (message)
594	{
595	/* DEBUG : append message to ICMP packet */
596	int message_len;
597	char *cpnt;
598	message_len = strlen(message);
599	if (message_len > ICMP_MAXDATALEN)
600	message_len = ICMP_MAXDATALEN;
601	cpnt = (char *)m->m_data+m->m_len;
602	memcpy(cpnt, message, message_len);
603	m->m_len += message_len;
604	}
605	#endif
606
607	icp->icmp_cksum = 0;
608	icp->icmp_cksum = cksum(m, m->m_len);
609
610	m->m_data -= hlen;
611	m->m_len += hlen;
612
613	/* fill in ip */
614	ip->ip_hl = hlen >> 2;
615	ip->ip_len = m->m_len;
616
617	ip->ip_tos = ((ip->ip_tos & 0x1E) \| 0xC0); /* high priority for errors */
618
619	ip->ip_ttl = MAXTTL;
620	ip->ip_p = IPPROTO_ICMP;
621	ip->ip_dst = ip->ip_src; /* ip adresses */
622	ip->ip_src = alias_addr;
623
624	(void ) ip_output(pData, (struct socket *)NULL, m);
625
626	icmpstat.icps_reflect++;
627
628	end_error:
629	;
630	}
631	#undef ICMP_MAXDATALEN
632
633	/*
634	* Reflect the ip packet back to the source
635	*/
636	void
637	icmp_reflect(PNATState pData, struct mbuf *m)
638	{
639	register struct ip ip = mtod(m, struct ip );
640	int hlen = ip->ip_hl << 2;
641	int optlen = hlen - sizeof(struct ip );
642	register struct icmp *icp;
643
644	/*
645	* Send an icmp packet back to the ip level,
646	* after supplying a checksum.
647	*/
648	m->m_data += hlen;
649	m->m_len -= hlen;
650	icp = mtod(m, struct icmp *);
651
652	icp->icmp_cksum = 0;
653	icp->icmp_cksum = cksum(m, ip->ip_len - hlen);
654
655	m->m_data -= hlen;
656	m->m_len += hlen;
657
658	#ifndef VBOX_WITH_SLIRP_ICMP
659	/* fill in ip */
660	if (optlen > 0)
661	{
662	/*
663	* Strip out original options by copying rest of first
664	* mbuf's data back, and adjust the IP length.
665	*/
666	memmove((caddr_t)(ip + 1), (caddr_t)ip + hlen,
667	(unsigned )(m->m_len - hlen));
668	hlen -= optlen;
669	ip->ip_hl = hlen >> 2;
670	ip->ip_len -= optlen;
671	m->m_len -= optlen;
672	}
673	ip->ip_ttl = MAXTTL;
674	{
675	/* swap */
676	struct in_addr icmp_dst;
677	icmp_dst = ip->ip_dst;
678	ip->ip_dst = ip->ip_src;
679	ip->ip_src = icmp_dst;
680	}
681	#endif /* !VBOX_WITH_SLIRP_ICMP */
682
683	(void ) ip_output(pData, (struct socket *)NULL, m);
684
685	icmpstat.icps_reflect++;
686	}

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source: vbox/trunk/src/VBox/Devices/Network/slirp/ip_icmp.c@ 15472

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