Commit | Line | Data |
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373c0574 | 1 | /* ip_icmp.c 6.3 84/01/11 */ |
81a36a8d BJ |
2 | |
3 | #include "../h/param.h" | |
2b4b57cd | 4 | #include "../h/systm.h" |
81a36a8d | 5 | #include "../h/mbuf.h" |
cdad2eb1 | 6 | #include "../h/protosw.h" |
72e4f44e | 7 | #include "../h/socket.h" |
f4d55810 | 8 | #include "../h/time.h" |
6e7edb25 BJ |
9 | #include "../h/kernel.h" |
10 | ||
11 | #include "../net/route.h" | |
f4d55810 | 12 | |
fcfe450e BJ |
13 | #include "../netinet/in.h" |
14 | #include "../netinet/in_systm.h" | |
15 | #include "../netinet/ip.h" | |
16 | #include "../netinet/ip_icmp.h" | |
7b66c1fd | 17 | #include "../netinet/icmp_var.h" |
81a36a8d | 18 | |
a60889ab | 19 | #ifdef ICMPPRINTFS |
81a36a8d BJ |
20 | /* |
21 | * ICMP routines: error generation, receive packet processing, and | |
22 | * routines to turnaround packets back to the originator, and | |
23 | * host table maintenance routines. | |
24 | */ | |
67387c9c | 25 | int icmpprintfs = 0; |
a60889ab | 26 | #endif |
81a36a8d BJ |
27 | |
28 | /* | |
72e4f44e SL |
29 | * Generate an error packet of type error |
30 | * in response to bad packet ip. | |
81a36a8d BJ |
31 | */ |
32 | icmp_error(oip, type, code) | |
33 | struct ip *oip; | |
755d8841 | 34 | int type, code; |
81a36a8d | 35 | { |
72e4f44e SL |
36 | register unsigned oiplen = oip->ip_hl << 2; |
37 | register struct icmp *icp; | |
81a36a8d BJ |
38 | struct mbuf *m; |
39 | struct ip *nip; | |
40 | ||
a60889ab | 41 | #ifdef ICMPPRINTFS |
39674d5f SL |
42 | if (icmpprintfs) |
43 | printf("icmp_error(%x, %d, %d)\n", oip, type, code); | |
a60889ab | 44 | #endif |
7b66c1fd | 45 | icmpstat.icps_error++; |
81a36a8d BJ |
46 | /* |
47 | * Make sure that the old IP packet had 8 bytes of data to return; | |
48 | * if not, don't bother. Also don't EVER error if the old | |
49 | * packet protocol was ICMP. | |
50 | */ | |
7b66c1fd SL |
51 | if (oip->ip_len < 8) { |
52 | icmpstat.icps_oldshort++; | |
81a36a8d | 53 | goto free; |
7b66c1fd SL |
54 | } |
55 | if (oip->ip_p == IPPROTO_ICMP) { | |
56 | icmpstat.icps_oldicmp++; | |
57 | goto free; | |
58 | } | |
81a36a8d BJ |
59 | |
60 | /* | |
72e4f44e | 61 | * First, formulate icmp message |
81a36a8d | 62 | */ |
cce93e4b | 63 | m = m_get(M_DONTWAIT, MT_HEADER); |
7b66c1fd | 64 | if (m == NULL) |
81a36a8d | 65 | goto free; |
72e4f44e SL |
66 | m->m_len = oiplen + 8 + ICMP_MINLEN; |
67 | m->m_off = MMAXOFF - m->m_len; | |
68 | icp = mtod(m, struct icmp *); | |
755d8841 | 69 | if ((u_int)type > ICMP_IREQREPLY) |
7b66c1fd SL |
70 | panic("icmp_error"); |
71 | icmpstat.icps_outhist[type]++; | |
81a36a8d | 72 | icp->icmp_type = type; |
72e4f44e | 73 | icp->icmp_void = 0; |
81a36a8d | 74 | if (type == ICMP_PARAMPROB) { |
81a36a8d | 75 | icp->icmp_pptr = code; |
72e4f44e SL |
76 | code = 0; |
77 | } | |
78 | icp->icmp_code = code; | |
d52566dd | 79 | bcopy((caddr_t)oip, (caddr_t)&icp->icmp_ip, oiplen + 8); |
39674d5f SL |
80 | nip = &icp->icmp_ip; |
81 | nip->ip_len += oiplen; | |
39674d5f | 82 | nip->ip_len = htons((u_short)nip->ip_len); |
81a36a8d BJ |
83 | |
84 | /* | |
72e4f44e SL |
85 | * Now, copy old ip header in front of icmp |
86 | * message. This allows us to reuse any source | |
87 | * routing info present. | |
81a36a8d | 88 | */ |
72e4f44e SL |
89 | m->m_off -= oiplen; |
90 | nip = mtod(m, struct ip *); | |
91 | bcopy((caddr_t)oip, (caddr_t)nip, oiplen); | |
92 | nip->ip_len = m->m_len + oiplen; | |
93 | nip->ip_p = IPPROTO_ICMP; | |
94 | /* icmp_send adds ip header to m_off and m_len, so we deduct here */ | |
95 | m->m_off += oiplen; | |
d52566dd | 96 | icmp_reflect(nip); |
81a36a8d | 97 | |
def04636 | 98 | free: |
81a36a8d BJ |
99 | m_freem(dtom(oip)); |
100 | } | |
101 | ||
72e4f44e SL |
102 | static struct sockproto icmproto = { AF_INET, IPPROTO_ICMP }; |
103 | static struct sockaddr_in icmpsrc = { AF_INET }; | |
104 | static struct sockaddr_in icmpdst = { AF_INET }; | |
105 | ||
81a36a8d | 106 | /* |
d52566dd | 107 | * Process a received ICMP message. |
81a36a8d BJ |
108 | */ |
109 | icmp_input(m) | |
110 | struct mbuf *m; | |
111 | { | |
81a36a8d | 112 | register struct icmp *icp; |
d52566dd | 113 | register struct ip *ip = mtod(m, struct ip *); |
af8f6a21 | 114 | int icmplen = ip->ip_len, hlen = ip->ip_hl << 2; |
7b66c1fd | 115 | int (*ctlfunc)(), code, i; |
b454c3ea | 116 | extern u_char ip_protox[]; |
81a36a8d BJ |
117 | |
118 | /* | |
119 | * Locate icmp structure in mbuf, and check | |
120 | * that not corrupted and of at least minimum length. | |
121 | */ | |
a60889ab | 122 | #ifdef ICMPPRINTFS |
39674d5f SL |
123 | if (icmpprintfs) |
124 | printf("icmp_input from %x, len %d\n", ip->ip_src, icmplen); | |
a60889ab | 125 | #endif |
167351c2 | 126 | if (icmplen < sizeof(struct ip) + ICMP_MINLEN) { |
7b66c1fd | 127 | icmpstat.icps_tooshort++; |
72e4f44e | 128 | goto free; |
7b66c1fd | 129 | } |
167351c2 MK |
130 | if ((m->m_off > MMAXOFF || m->m_len < icmplen) |
131 | && (m = m_pullup(m, icmplen)) == 0) { | |
132 | icmpstat.icps_tooshort++; | |
133 | return; | |
134 | } | |
81a36a8d BJ |
135 | m->m_len -= hlen; |
136 | m->m_off += hlen; | |
72e4f44e | 137 | icp = mtod(m, struct icmp *); |
81a36a8d BJ |
138 | i = icp->icmp_cksum; |
139 | icp->icmp_cksum = 0; | |
72e4f44e | 140 | if (i != in_cksum(m, icmplen)) { |
7b66c1fd | 141 | icmpstat.icps_checksum++; |
d52566dd | 142 | goto free; |
72e4f44e | 143 | } |
81a36a8d | 144 | |
a60889ab | 145 | #ifdef ICMPPRINTFS |
81a36a8d BJ |
146 | /* |
147 | * Message type specific processing. | |
148 | */ | |
39674d5f SL |
149 | if (icmpprintfs) |
150 | printf("icmp_input, type %d code %d\n", icp->icmp_type, | |
a60889ab KM |
151 | icp->icmp_code); |
152 | #endif | |
7b66c1fd SL |
153 | if (icp->icmp_type > ICMP_IREQREPLY) |
154 | goto free; | |
155 | icmpstat.icps_inhist[icp->icmp_type]++; | |
a60889ab | 156 | code = icp->icmp_code; |
7b66c1fd | 157 | switch (icp->icmp_type) { |
81a36a8d BJ |
158 | |
159 | case ICMP_UNREACH: | |
a60889ab KM |
160 | if (code > 5) |
161 | goto badcode; | |
162 | code += PRC_UNREACH_NET; | |
163 | goto deliver; | |
164 | ||
81a36a8d | 165 | case ICMP_TIMXCEED: |
a60889ab KM |
166 | if (code > 1) |
167 | goto badcode; | |
168 | code += PRC_TIMXCEED_INTRANS; | |
169 | goto deliver; | |
170 | ||
81a36a8d | 171 | case ICMP_PARAMPROB: |
a60889ab KM |
172 | if (code) |
173 | goto badcode; | |
174 | code = PRC_PARAMPROB; | |
175 | goto deliver; | |
176 | ||
72e4f44e | 177 | case ICMP_SOURCEQUENCH: |
a60889ab KM |
178 | if (code) |
179 | goto badcode; | |
180 | code = PRC_QUENCH; | |
181 | deliver: | |
81a36a8d | 182 | /* |
a60889ab | 183 | * Problem with datagram; advise higher level routines. |
81a36a8d | 184 | */ |
a1edc12b | 185 | icp->icmp_ip.ip_len = ntohs((u_short)icp->icmp_ip.ip_len); |
7b66c1fd SL |
186 | if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp)) { |
187 | icmpstat.icps_badlen++; | |
d52566dd | 188 | goto free; |
7b66c1fd | 189 | } |
a60889ab | 190 | #ifdef ICMPPRINTFS |
39674d5f SL |
191 | if (icmpprintfs) |
192 | printf("deliver to protocol %d\n", icp->icmp_ip.ip_p); | |
a60889ab | 193 | #endif |
59965020 | 194 | if (ctlfunc = inetsw[ip_protox[icp->icmp_ip.ip_p]].pr_ctlinput) |
a60889ab KM |
195 | (*ctlfunc)(code, (caddr_t)icp); |
196 | goto free; | |
197 | ||
198 | badcode: | |
199 | icmpstat.icps_badcode++; | |
81a36a8d BJ |
200 | goto free; |
201 | ||
202 | case ICMP_ECHO: | |
203 | icp->icmp_type = ICMP_ECHOREPLY; | |
204 | goto reflect; | |
205 | ||
206 | case ICMP_TSTAMP: | |
7b66c1fd SL |
207 | if (icmplen < ICMP_TSLEN) { |
208 | icmpstat.icps_badlen++; | |
d52566dd | 209 | goto free; |
7b66c1fd | 210 | } |
81a36a8d | 211 | icp->icmp_type = ICMP_TSTAMPREPLY; |
2b4b57cd | 212 | icp->icmp_rtime = iptime(); |
81a36a8d BJ |
213 | icp->icmp_ttime = icp->icmp_rtime; /* bogus, do later! */ |
214 | goto reflect; | |
215 | ||
216 | case ICMP_IREQ: | |
a60889ab | 217 | #ifdef notdef |
81a36a8d BJ |
218 | /* fill in source address zero fields! */ |
219 | goto reflect; | |
a60889ab KM |
220 | #else |
221 | goto free; /* not yet implemented: ignore */ | |
222 | #endif | |
81a36a8d | 223 | |
a469458a | 224 | case ICMP_REDIRECT: |
7b66c1fd SL |
225 | if (icmplen < ICMP_ADVLENMIN || icmplen < ICMP_ADVLEN(icp)) { |
226 | icmpstat.icps_badlen++; | |
d52566dd | 227 | goto free; |
7b66c1fd | 228 | } |
a469458a SL |
229 | /* |
230 | * Short circuit routing redirects to force | |
231 | * immediate change in the kernel's routing | |
232 | * tables. The message is also handed to anyone | |
233 | * listening on a raw socket (e.g. the routing | |
234 | * daemon for use in updating it's tables). | |
235 | */ | |
167351c2 MK |
236 | icmpsrc.sin_addr = icp->icmp_ip.ip_dst; |
237 | icmpdst.sin_addr = icp->icmp_gwaddr; | |
238 | rtredirect((struct sockaddr *)&icmpsrc, | |
239 | (struct sockaddr *)&icmpdst, | |
240 | (code == ICMP_REDIRECT_NET || code == ICMP_REDIRECT_TOSNET) ? | |
241 | RTF_GATEWAY : (RTF_GATEWAY | RTF_HOST)); | |
242 | /* FALL THROUGH */ | |
243 | ||
244 | case ICMP_ECHOREPLY: | |
245 | case ICMP_TSTAMPREPLY: | |
246 | case ICMP_IREQREPLY: | |
72e4f44e SL |
247 | icmpsrc.sin_addr = ip->ip_src; |
248 | icmpdst.sin_addr = ip->ip_dst; | |
249 | raw_input(dtom(icp), &icmproto, (struct sockaddr *)&icmpsrc, | |
250 | (struct sockaddr *)&icmpdst); | |
fd15a680 | 251 | return; |
81a36a8d BJ |
252 | |
253 | default: | |
254 | goto free; | |
255 | } | |
256 | reflect: | |
b012ee63 | 257 | ip->ip_len += hlen; /* since ip_input deducts this */ |
7b66c1fd | 258 | icmpstat.icps_reflect++; |
81a36a8d | 259 | icmp_reflect(ip); |
af8f6a21 | 260 | return; |
81a36a8d BJ |
261 | free: |
262 | m_freem(dtom(ip)); | |
263 | } | |
264 | ||
265 | /* | |
266 | * Reflect the ip packet back to the source | |
72e4f44e | 267 | * TODO: rearrange ip source routing options. |
81a36a8d BJ |
268 | */ |
269 | icmp_reflect(ip) | |
270 | struct ip *ip; | |
271 | { | |
2b4b57cd | 272 | struct in_addr t; |
81a36a8d | 273 | |
72e4f44e SL |
274 | t = ip->ip_dst; |
275 | ip->ip_dst = ip->ip_src; | |
276 | ip->ip_src = t; | |
81a36a8d BJ |
277 | icmp_send(ip); |
278 | } | |
279 | ||
280 | /* | |
72e4f44e SL |
281 | * Send an icmp packet back to the ip level, |
282 | * after supplying a checksum. | |
81a36a8d | 283 | */ |
cdad2eb1 | 284 | icmp_send(ip) |
81a36a8d | 285 | struct ip *ip; |
81a36a8d | 286 | { |
af8f6a21 | 287 | register int hlen; |
72e4f44e | 288 | register struct icmp *icp; |
af8f6a21 | 289 | register struct mbuf *m; |
d52566dd | 290 | |
af8f6a21 SL |
291 | m = dtom(ip); |
292 | hlen = ip->ip_hl << 2; | |
72e4f44e SL |
293 | icp = mtod(m, struct icmp *); |
294 | icp->icmp_cksum = 0; | |
295 | icp->icmp_cksum = in_cksum(m, ip->ip_len - hlen); | |
296 | m->m_off -= hlen; | |
297 | m->m_len += hlen; | |
a60889ab | 298 | #ifdef ICMPPRINTFS |
39674d5f SL |
299 | if (icmpprintfs) |
300 | printf("icmp_send dst %x src %x\n", ip->ip_dst, ip->ip_src); | |
a60889ab | 301 | #endif |
a1edc12b | 302 | (void) ip_output(m, (struct mbuf *)0, (struct route *)0, 0); |
d52566dd BJ |
303 | } |
304 | ||
cdad2eb1 | 305 | n_time |
2b4b57cd | 306 | iptime() |
d52566dd | 307 | { |
cdad2eb1 | 308 | int s = spl6(); |
2752c877 | 309 | u_long t; |
d52566dd | 310 | |
b2ac7f3b | 311 | t = (time.tv_sec % (24*60*60)) * 1000 + time.tv_usec / 1000; |
cdad2eb1 BJ |
312 | splx(s); |
313 | return (htonl(t)); | |
d52566dd | 314 | } |