Commit | Line | Data |
---|---|---|
0270e817 | 1 | /* ip_icmp.c 6.11 85/05/27 */ |
81a36a8d | 2 | |
20666ad3 JB |
3 | #include "param.h" |
4 | #include "systm.h" | |
5 | #include "mbuf.h" | |
6 | #include "protosw.h" | |
7 | #include "socket.h" | |
8 | #include "time.h" | |
9 | #include "kernel.h" | |
6e7edb25 BJ |
10 | |
11 | #include "../net/route.h" | |
c175a1bd | 12 | #include "../net/if.h" |
f4d55810 | 13 | |
20666ad3 JB |
14 | #include "in.h" |
15 | #include "in_systm.h" | |
c175a1bd | 16 | #include "in_var.h" |
20666ad3 JB |
17 | #include "ip.h" |
18 | #include "ip_icmp.h" | |
19 | #include "icmp_var.h" | |
81a36a8d | 20 | |
a60889ab | 21 | #ifdef ICMPPRINTFS |
81a36a8d BJ |
22 | /* |
23 | * ICMP routines: error generation, receive packet processing, and | |
24 | * routines to turnaround packets back to the originator, and | |
25 | * host table maintenance routines. | |
26 | */ | |
67387c9c | 27 | int icmpprintfs = 0; |
a60889ab | 28 | #endif |
81a36a8d BJ |
29 | |
30 | /* | |
72e4f44e SL |
31 | * Generate an error packet of type error |
32 | * in response to bad packet ip. | |
81a36a8d BJ |
33 | */ |
34 | icmp_error(oip, type, code) | |
35 | struct ip *oip; | |
755d8841 | 36 | int type, code; |
81a36a8d | 37 | { |
72e4f44e SL |
38 | register unsigned oiplen = oip->ip_hl << 2; |
39 | register struct icmp *icp; | |
81a36a8d BJ |
40 | struct mbuf *m; |
41 | struct ip *nip; | |
42 | ||
a60889ab | 43 | #ifdef ICMPPRINTFS |
39674d5f SL |
44 | if (icmpprintfs) |
45 | printf("icmp_error(%x, %d, %d)\n", oip, type, code); | |
a60889ab | 46 | #endif |
7b66c1fd | 47 | icmpstat.icps_error++; |
81a36a8d BJ |
48 | /* |
49 | * Make sure that the old IP packet had 8 bytes of data to return; | |
50 | * if not, don't bother. Also don't EVER error if the old | |
51 | * packet protocol was ICMP. | |
52 | */ | |
7b66c1fd SL |
53 | if (oip->ip_len < 8) { |
54 | icmpstat.icps_oldshort++; | |
81a36a8d | 55 | goto free; |
7b66c1fd SL |
56 | } |
57 | if (oip->ip_p == IPPROTO_ICMP) { | |
58 | icmpstat.icps_oldicmp++; | |
59 | goto free; | |
60 | } | |
81a36a8d BJ |
61 | |
62 | /* | |
72e4f44e | 63 | * First, formulate icmp message |
81a36a8d | 64 | */ |
cce93e4b | 65 | m = m_get(M_DONTWAIT, MT_HEADER); |
7b66c1fd | 66 | if (m == NULL) |
81a36a8d | 67 | goto free; |
72e4f44e SL |
68 | m->m_len = oiplen + 8 + ICMP_MINLEN; |
69 | m->m_off = MMAXOFF - m->m_len; | |
70 | icp = mtod(m, struct icmp *); | |
755d8841 | 71 | if ((u_int)type > ICMP_IREQREPLY) |
7b66c1fd SL |
72 | panic("icmp_error"); |
73 | icmpstat.icps_outhist[type]++; | |
81a36a8d | 74 | icp->icmp_type = type; |
72e4f44e | 75 | icp->icmp_void = 0; |
81a36a8d | 76 | if (type == ICMP_PARAMPROB) { |
81a36a8d | 77 | icp->icmp_pptr = code; |
72e4f44e SL |
78 | code = 0; |
79 | } | |
80 | icp->icmp_code = code; | |
d52566dd | 81 | bcopy((caddr_t)oip, (caddr_t)&icp->icmp_ip, oiplen + 8); |
39674d5f SL |
82 | nip = &icp->icmp_ip; |
83 | nip->ip_len += oiplen; | |
39674d5f | 84 | nip->ip_len = htons((u_short)nip->ip_len); |
81a36a8d BJ |
85 | |
86 | /* | |
72e4f44e SL |
87 | * Now, copy old ip header in front of icmp |
88 | * message. This allows us to reuse any source | |
89 | * routing info present. | |
81a36a8d | 90 | */ |
72e4f44e SL |
91 | m->m_off -= oiplen; |
92 | nip = mtod(m, struct ip *); | |
93 | bcopy((caddr_t)oip, (caddr_t)nip, oiplen); | |
94 | nip->ip_len = m->m_len + oiplen; | |
95 | nip->ip_p = IPPROTO_ICMP; | |
96 | /* icmp_send adds ip header to m_off and m_len, so we deduct here */ | |
97 | m->m_off += oiplen; | |
d52566dd | 98 | icmp_reflect(nip); |
81a36a8d | 99 | |
def04636 | 100 | free: |
81a36a8d BJ |
101 | m_freem(dtom(oip)); |
102 | } | |
103 | ||
72e4f44e SL |
104 | static struct sockproto icmproto = { AF_INET, IPPROTO_ICMP }; |
105 | static struct sockaddr_in icmpsrc = { AF_INET }; | |
106 | static struct sockaddr_in icmpdst = { AF_INET }; | |
107 | ||
81a36a8d | 108 | /* |
d52566dd | 109 | * Process a received ICMP message. |
81a36a8d BJ |
110 | */ |
111 | icmp_input(m) | |
112 | struct mbuf *m; | |
113 | { | |
81a36a8d | 114 | register struct icmp *icp; |
d52566dd | 115 | register struct ip *ip = mtod(m, struct ip *); |
af8f6a21 | 116 | int icmplen = ip->ip_len, hlen = ip->ip_hl << 2; |
8046f415 MK |
117 | register int i; |
118 | int (*ctlfunc)(), code; | |
b454c3ea | 119 | extern u_char ip_protox[]; |
c175a1bd | 120 | extern struct in_addr in_makeaddr(); |
81a36a8d BJ |
121 | |
122 | /* | |
123 | * Locate icmp structure in mbuf, and check | |
124 | * that not corrupted and of at least minimum length. | |
125 | */ | |
a60889ab | 126 | #ifdef ICMPPRINTFS |
39674d5f SL |
127 | if (icmpprintfs) |
128 | printf("icmp_input from %x, len %d\n", ip->ip_src, icmplen); | |
a60889ab | 129 | #endif |
4d75f980 | 130 | if (icmplen < ICMP_MINLEN) { |
7b66c1fd | 131 | icmpstat.icps_tooshort++; |
72e4f44e | 132 | goto free; |
7b66c1fd | 133 | } |
8046f415 MK |
134 | /* THIS LENGTH CHECK STILL MISSES ANY IP OPTIONS IN ICMP_IP */ |
135 | i = MIN(icmplen, ICMP_ADVLENMIN + hlen); | |
136 | if ((m->m_off > MMAXOFF || m->m_len < i) && | |
137 | (m = m_pullup(m, i)) == 0) { | |
167351c2 MK |
138 | icmpstat.icps_tooshort++; |
139 | return; | |
140 | } | |
8046f415 | 141 | ip = mtod(m, struct ip *); |
81a36a8d BJ |
142 | m->m_len -= hlen; |
143 | m->m_off += hlen; | |
72e4f44e | 144 | icp = mtod(m, struct icmp *); |
8046f415 | 145 | if (in_cksum(m, icmplen)) { |
7b66c1fd | 146 | icmpstat.icps_checksum++; |
d52566dd | 147 | goto free; |
72e4f44e | 148 | } |
81a36a8d | 149 | |
a60889ab | 150 | #ifdef ICMPPRINTFS |
81a36a8d BJ |
151 | /* |
152 | * Message type specific processing. | |
153 | */ | |
39674d5f SL |
154 | if (icmpprintfs) |
155 | printf("icmp_input, type %d code %d\n", icp->icmp_type, | |
a60889ab KM |
156 | icp->icmp_code); |
157 | #endif | |
7b66c1fd SL |
158 | if (icp->icmp_type > ICMP_IREQREPLY) |
159 | goto free; | |
160 | icmpstat.icps_inhist[icp->icmp_type]++; | |
a60889ab | 161 | code = icp->icmp_code; |
7b66c1fd | 162 | switch (icp->icmp_type) { |
81a36a8d BJ |
163 | |
164 | case ICMP_UNREACH: | |
a60889ab KM |
165 | if (code > 5) |
166 | goto badcode; | |
167 | code += PRC_UNREACH_NET; | |
168 | goto deliver; | |
169 | ||
81a36a8d | 170 | case ICMP_TIMXCEED: |
a60889ab KM |
171 | if (code > 1) |
172 | goto badcode; | |
173 | code += PRC_TIMXCEED_INTRANS; | |
174 | goto deliver; | |
175 | ||
81a36a8d | 176 | case ICMP_PARAMPROB: |
a60889ab KM |
177 | if (code) |
178 | goto badcode; | |
179 | code = PRC_PARAMPROB; | |
180 | goto deliver; | |
181 | ||
72e4f44e | 182 | case ICMP_SOURCEQUENCH: |
a60889ab KM |
183 | if (code) |
184 | goto badcode; | |
185 | code = PRC_QUENCH; | |
186 | deliver: | |
81a36a8d | 187 | /* |
a60889ab | 188 | * Problem with datagram; advise higher level routines. |
81a36a8d | 189 | */ |
a1edc12b | 190 | icp->icmp_ip.ip_len = ntohs((u_short)icp->icmp_ip.ip_len); |
7b66c1fd SL |
191 | if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp)) { |
192 | icmpstat.icps_badlen++; | |
d52566dd | 193 | goto free; |
7b66c1fd | 194 | } |
a60889ab | 195 | #ifdef ICMPPRINTFS |
39674d5f SL |
196 | if (icmpprintfs) |
197 | printf("deliver to protocol %d\n", icp->icmp_ip.ip_p); | |
a60889ab | 198 | #endif |
59965020 | 199 | if (ctlfunc = inetsw[ip_protox[icp->icmp_ip.ip_p]].pr_ctlinput) |
a60889ab KM |
200 | (*ctlfunc)(code, (caddr_t)icp); |
201 | goto free; | |
202 | ||
203 | badcode: | |
204 | icmpstat.icps_badcode++; | |
81a36a8d BJ |
205 | goto free; |
206 | ||
207 | case ICMP_ECHO: | |
208 | icp->icmp_type = ICMP_ECHOREPLY; | |
209 | goto reflect; | |
210 | ||
211 | case ICMP_TSTAMP: | |
7b66c1fd SL |
212 | if (icmplen < ICMP_TSLEN) { |
213 | icmpstat.icps_badlen++; | |
d52566dd | 214 | goto free; |
7b66c1fd | 215 | } |
81a36a8d | 216 | icp->icmp_type = ICMP_TSTAMPREPLY; |
2b4b57cd | 217 | icp->icmp_rtime = iptime(); |
81a36a8d BJ |
218 | icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */ |
219 | goto reflect; | |
220 | ||
221 | case ICMP_IREQ: | |
c175a1bd MK |
222 | #define satosin(sa) ((struct sockaddr_in *)(sa)) |
223 | if (in_netof(ip->ip_src) == 0) | |
224 | ip->ip_src = in_makeaddr( | |
225 | in_netof(satosin(&in_ifaddr->ia_addr)->sin_addr), | |
226 | in_lnaof(ip->ip_src)); | |
227 | icp->icmp_type = ICMP_IREQREPLY; | |
81a36a8d BJ |
228 | goto reflect; |
229 | ||
a469458a | 230 | case ICMP_REDIRECT: |
7b66c1fd SL |
231 | if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp)) { |
232 | icmpstat.icps_badlen++; | |
d52566dd | 233 | goto free; |
7b66c1fd | 234 | } |
a469458a SL |
235 | /* |
236 | * Short circuit routing redirects to force | |
237 | * immediate change in the kernel's routing | |
238 | * tables. The message is also handed to anyone | |
239 | * listening on a raw socket (e.g. the routing | |
fbc81152 | 240 | * daemon for use in updating its tables). |
a469458a | 241 | */ |
167351c2 | 242 | icmpdst.sin_addr = icp->icmp_gwaddr; |
fbc81152 MK |
243 | if (code == ICMP_REDIRECT_NET || code == ICMP_REDIRECT_TOSNET) { |
244 | icmpsrc.sin_addr = | |
c175a1bd | 245 | in_makeaddr(in_netof(icp->icmp_ip.ip_dst), INADDR_ANY); |
fbc81152 MK |
246 | rtredirect((struct sockaddr *)&icmpsrc, |
247 | (struct sockaddr *)&icmpdst, RTF_GATEWAY); | |
0270e817 | 248 | pfctlinput(PRC_REDIRECT_NET, (caddr_t)icp); |
fbc81152 MK |
249 | } else { |
250 | icmpsrc.sin_addr = icp->icmp_ip.ip_dst; | |
251 | rtredirect((struct sockaddr *)&icmpsrc, | |
252 | (struct sockaddr *)&icmpdst, RTF_GATEWAY | RTF_HOST); | |
0270e817 | 253 | pfctlinput(PRC_REDIRECT_HOST, (caddr_t)icp); |
fbc81152 | 254 | } |
167351c2 MK |
255 | /* FALL THROUGH */ |
256 | ||
257 | case ICMP_ECHOREPLY: | |
258 | case ICMP_TSTAMPREPLY: | |
259 | case ICMP_IREQREPLY: | |
72e4f44e SL |
260 | icmpsrc.sin_addr = ip->ip_src; |
261 | icmpdst.sin_addr = ip->ip_dst; | |
262 | raw_input(dtom(icp), &icmproto, (struct sockaddr *)&icmpsrc, | |
263 | (struct sockaddr *)&icmpdst); | |
fd15a680 | 264 | return; |
81a36a8d BJ |
265 | |
266 | default: | |
267 | goto free; | |
268 | } | |
269 | reflect: | |
b012ee63 | 270 | ip->ip_len += hlen; /* since ip_input deducts this */ |
7b66c1fd | 271 | icmpstat.icps_reflect++; |
06730e5a | 272 | icmpstat.icps_outhist[icp->icmp_type]++; |
81a36a8d | 273 | icmp_reflect(ip); |
af8f6a21 | 274 | return; |
81a36a8d BJ |
275 | free: |
276 | m_freem(dtom(ip)); | |
277 | } | |
278 | ||
279 | /* | |
280 | * Reflect the ip packet back to the source | |
72e4f44e | 281 | * TODO: rearrange ip source routing options. |
81a36a8d BJ |
282 | */ |
283 | icmp_reflect(ip) | |
284 | struct ip *ip; | |
285 | { | |
c175a1bd MK |
286 | register struct in_addr t; |
287 | register struct in_ifaddr *ia; | |
81a36a8d | 288 | |
72e4f44e | 289 | t = ip->ip_dst; |
c175a1bd MK |
290 | if (t.s_addr == INADDR_ANY) |
291 | t = IA_SIN(in_ifaddr)->sin_addr; | |
292 | else for (ia = in_ifaddr; ia; ia = ia->ia_next) | |
293 | if (t.s_addr == satosin(&ia->ia_broadaddr)->sin_addr.s_addr && | |
294 | (ia->ia_ifp->if_flags & IFF_BROADCAST)) { | |
295 | t = IA_SIN(ia)->sin_addr; | |
296 | break; | |
297 | } | |
72e4f44e SL |
298 | ip->ip_dst = ip->ip_src; |
299 | ip->ip_src = t; | |
81a36a8d BJ |
300 | icmp_send(ip); |
301 | } | |
302 | ||
303 | /* | |
72e4f44e SL |
304 | * Send an icmp packet back to the ip level, |
305 | * after supplying a checksum. | |
81a36a8d | 306 | */ |
cdad2eb1 | 307 | icmp_send(ip) |
81a36a8d | 308 | struct ip *ip; |
81a36a8d | 309 | { |
af8f6a21 | 310 | register int hlen; |
72e4f44e | 311 | register struct icmp *icp; |
af8f6a21 | 312 | register struct mbuf *m; |
d52566dd | 313 | |
af8f6a21 SL |
314 | m = dtom(ip); |
315 | hlen = ip->ip_hl << 2; | |
72e4f44e SL |
316 | icp = mtod(m, struct icmp *); |
317 | icp->icmp_cksum = 0; | |
318 | icp->icmp_cksum = in_cksum(m, ip->ip_len - hlen); | |
319 | m->m_off -= hlen; | |
320 | m->m_len += hlen; | |
a60889ab | 321 | #ifdef ICMPPRINTFS |
39674d5f SL |
322 | if (icmpprintfs) |
323 | printf("icmp_send dst %x src %x\n", ip->ip_dst, ip->ip_src); | |
a60889ab | 324 | #endif |
a1edc12b | 325 | (void) ip_output(m, (struct mbuf *)0, (struct route *)0, 0); |
d52566dd BJ |
326 | } |
327 | ||
cdad2eb1 | 328 | n_time |
2b4b57cd | 329 | iptime() |
d52566dd | 330 | { |
cdad2eb1 | 331 | int s = spl6(); |
2752c877 | 332 | u_long t; |
d52566dd | 333 | |
b2ac7f3b | 334 | t = (time.tv_sec % (24*60*60)) * 1000 + time.tv_usec / 1000; |
cdad2eb1 BJ |
335 | splx(s); |
336 | return (htonl(t)); | |
d52566dd | 337 | } |