1 /* $OpenBSD: print-icmp.c,v 1.26 2020/01/24 22:46:36 procter Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that: (1) source code distributions 9 * retain the above copyright notice and this paragraph in its entirety, (2) 10 * distributions including binary code include the above copyright notice and 11 * this paragraph in its entirety in the documentation or other materials 12 * provided with the distribution, and (3) all advertising materials mentioning 13 * features or use of this software display the following acknowledgement: 14 * ``This product includes software developed by the University of California, 15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 16 * the University nor the names of its contributors may be used to endorse 17 * or promote products derived from this software without specific prior 18 * written permission. 19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 22 */ 23 24 #include <sys/time.h> 25 #include <sys/socket.h> 26 27 struct mbuf; 28 struct rtentry; 29 #include <net/if.h> 30 31 #include <netinet/in.h> 32 #include <netinet/if_ether.h> 33 #include <netinet/ip.h> 34 #include <netinet/ip_icmp.h> 35 #include <netinet/ip_var.h> 36 #include <netinet/udp.h> 37 #include <netinet/udp_var.h> 38 #include <netinet/tcp.h> 39 40 #include <stdio.h> 41 #include <string.h> 42 #include <limits.h> 43 44 #include "interface.h" 45 #include "addrtoname.h" 46 #include "extract.h" /* must come after interface.h */ 47 48 /* rfc1700 */ 49 #ifndef ICMP_UNREACH_NET_UNKNOWN 50 #define ICMP_UNREACH_NET_UNKNOWN 6 /* destination net unknown */ 51 #endif 52 #ifndef ICMP_UNREACH_HOST_UNKNOWN 53 #define ICMP_UNREACH_HOST_UNKNOWN 7 /* destination host unknown */ 54 #endif 55 #ifndef ICMP_UNREACH_ISOLATED 56 #define ICMP_UNREACH_ISOLATED 8 /* source host isolated */ 57 #endif 58 #ifndef ICMP_UNREACH_NET_PROHIB 59 #define ICMP_UNREACH_NET_PROHIB 9 /* admin prohibited net */ 60 #endif 61 #ifndef ICMP_UNREACH_HOST_PROHIB 62 #define ICMP_UNREACH_HOST_PROHIB 10 /* admin prohibited host */ 63 #endif 64 #ifndef ICMP_UNREACH_TOSNET 65 #define ICMP_UNREACH_TOSNET 11 /* tos prohibited net */ 66 #endif 67 #ifndef ICMP_UNREACH_TOSHOST 68 #define ICMP_UNREACH_TOSHOST 12 /* tos prohibited host */ 69 #endif 70 71 /* rfc1716 */ 72 #ifndef ICMP_UNREACH_FILTER_PROHIB 73 #define ICMP_UNREACH_FILTER_PROHIB 13 /* admin prohibited filter */ 74 #endif 75 #ifndef ICMP_UNREACH_HOST_PRECEDENCE 76 #define ICMP_UNREACH_HOST_PRECEDENCE 14 /* host precedence violation */ 77 #endif 78 #ifndef ICMP_UNREACH_PRECEDENCE_CUTOFF 79 #define ICMP_UNREACH_PRECEDENCE_CUTOFF 15 /* precedence cutoff */ 80 #endif 81 82 /* rfc1256 */ 83 #ifndef ICMP_ROUTERADVERT 84 #define ICMP_ROUTERADVERT 9 /* router advertisement */ 85 #endif 86 #ifndef ICMP_ROUTERSOLICIT 87 #define ICMP_ROUTERSOLICIT 10 /* router solicitation */ 88 #endif 89 90 #define ICMP_INFOTYPE(type) \ 91 ((type) == ICMP_ECHOREPLY || (type) == ICMP_ECHO || \ 92 (type) == ICMP_ROUTERADVERT || (type) == ICMP_ROUTERSOLICIT || \ 93 (type) == ICMP_TSTAMP || (type) == ICMP_TSTAMPREPLY || \ 94 (type) == ICMP_IREQ || (type) == ICMP_IREQREPLY || \ 95 (type) == ICMP_MASKREQ || (type) == ICMP_MASKREPLY) 96 97 /* Most of the icmp types */ 98 static struct tok icmp2str[] = { 99 { ICMP_ECHOREPLY, "echo reply" }, 100 { ICMP_SOURCEQUENCH, "source quench" }, 101 { ICMP_ECHO, "echo request" }, 102 { ICMP_ROUTERSOLICIT, "router solicitation" }, 103 { ICMP_TSTAMP, "time stamp request" }, 104 { ICMP_TSTAMPREPLY, "time stamp reply" }, 105 { ICMP_IREQ, "information request" }, 106 { ICMP_IREQREPLY, "information reply" }, 107 { ICMP_MASKREQ, "address mask request" }, 108 { 0, NULL } 109 }; 110 111 /* Formats for most of the ICMP_UNREACH codes */ 112 static struct tok unreach2str[] = { 113 { ICMP_UNREACH_NET, "net %s unreachable" }, 114 { ICMP_UNREACH_HOST, "host %s unreachable" }, 115 { ICMP_UNREACH_SRCFAIL, 116 "%s unreachable - source route failed" }, 117 { ICMP_UNREACH_NET_UNKNOWN, "net %s unreachable - unknown" }, 118 { ICMP_UNREACH_HOST_UNKNOWN, "host %s unreachable - unknown" }, 119 { ICMP_UNREACH_ISOLATED, 120 "%s unreachable - source host isolated" }, 121 { ICMP_UNREACH_NET_PROHIB, 122 "net %s unreachable - admin prohibited" }, 123 { ICMP_UNREACH_HOST_PROHIB, 124 "host %s unreachable - admin prohibited" }, 125 { ICMP_UNREACH_TOSNET, 126 "net %s unreachable - tos prohibited" }, 127 { ICMP_UNREACH_TOSHOST, 128 "host %s unreachable - tos prohibited" }, 129 { ICMP_UNREACH_FILTER_PROHIB, 130 "host %s unreachable - admin prohibited filter" }, 131 { ICMP_UNREACH_HOST_PRECEDENCE, 132 "host %s unreachable - host precedence violation" }, 133 { ICMP_UNREACH_PRECEDENCE_CUTOFF, 134 "host %s unreachable - precedence cutoff" }, 135 { 0, NULL } 136 }; 137 138 /* Formats for the ICMP_REDIRECT codes */ 139 static struct tok type2str[] = { 140 { ICMP_REDIRECT_NET, "redirect %s to net %s" }, 141 { ICMP_REDIRECT_HOST, "redirect %s to host %s" }, 142 { ICMP_REDIRECT_TOSNET, "redirect-tos %s to net %s" }, 143 { ICMP_REDIRECT_TOSHOST, "redirect-tos %s to net %s" }, 144 { 0, NULL } 145 }; 146 147 /* rfc1191 */ 148 struct mtu_discovery { 149 short unused; 150 short nexthopmtu; 151 }; 152 153 /* rfc1256 */ 154 struct ih_rdiscovery { 155 u_char ird_addrnum; 156 u_char ird_addrsiz; 157 u_short ird_lifetime; 158 }; 159 160 struct id_rdiscovery { 161 u_int32_t ird_addr; 162 u_int32_t ird_pref; 163 }; 164 165 void 166 icmp_print(const u_char *bp, u_int length, const u_char *bp2) 167 { 168 const struct icmp *dp; 169 const struct ip *ip; 170 const char *str, *fmt; 171 const struct ip *oip; 172 const struct udphdr *ouh; 173 u_int hlen, dport, mtu; 174 char buf[HOST_NAME_MAX+1+256]; 175 char buf2[HOST_NAME_MAX+1+256]; 176 177 dp = (struct icmp *)bp; 178 ip = (struct ip *)bp2; 179 str = buf; 180 181 printf("%s > %s: ", 182 ipaddr_string(&ip->ip_src), 183 ipaddr_string(&ip->ip_dst)); 184 185 TCHECK(dp->icmp_code); 186 if (qflag) 187 (void) snprintf(buf, sizeof buf, "%u %u", dp->icmp_type, 188 dp->icmp_code); 189 else switch (dp->icmp_type) { 190 191 case ICMP_ECHOREPLY: 192 case ICMP_ECHO: 193 if (vflag) { 194 TCHECK(dp->icmp_seq); 195 (void)snprintf(buf, sizeof buf, 196 "echo %s (id:%04x seq:%u)", 197 (dp->icmp_type == ICMP_ECHO)? 198 "request": "reply", 199 ntohs(dp->icmp_id), 200 ntohs(dp->icmp_seq)); 201 } else 202 str = tok2str(icmp2str, "type-#%u", dp->icmp_type); 203 break; 204 205 case ICMP_UNREACH: 206 TCHECK(dp->icmp_ip.ip_dst); 207 switch (dp->icmp_code) { 208 209 case ICMP_UNREACH_PROTOCOL: 210 TCHECK(dp->icmp_ip.ip_p); 211 (void)snprintf(buf, sizeof buf, 212 "%s protocol %u unreachable", 213 ipaddr_string(&dp->icmp_ip.ip_dst), 214 dp->icmp_ip.ip_p); 215 break; 216 217 case ICMP_UNREACH_PORT: 218 TCHECK(dp->icmp_ip.ip_p); 219 oip = &dp->icmp_ip; 220 hlen = oip->ip_hl * 4; 221 ouh = (struct udphdr *)(((u_char *)oip) + hlen); 222 TCHECK(ouh->uh_dport); 223 dport = ntohs(ouh->uh_dport); 224 switch (oip->ip_p) { 225 226 case IPPROTO_TCP: 227 (void)snprintf(buf, sizeof buf, 228 "%s tcp port %s unreachable", 229 ipaddr_string(&oip->ip_dst), 230 tcpport_string(dport)); 231 break; 232 233 case IPPROTO_UDP: 234 (void)snprintf(buf, sizeof buf, 235 "%s udp port %s unreachable", 236 ipaddr_string(&oip->ip_dst), 237 udpport_string(dport)); 238 break; 239 240 default: 241 (void)snprintf(buf, sizeof buf, 242 "%s protocol %u port %u unreachable", 243 ipaddr_string(&oip->ip_dst), 244 oip->ip_p, dport); 245 break; 246 } 247 break; 248 249 case ICMP_UNREACH_NEEDFRAG: 250 { 251 const struct mtu_discovery *mp; 252 253 mp = (struct mtu_discovery *)&dp->icmp_void; 254 mtu = EXTRACT_16BITS(&mp->nexthopmtu); 255 if (mtu) 256 (void)snprintf(buf, sizeof buf, 257 "%s unreachable - need to frag (mtu %u)", 258 ipaddr_string(&dp->icmp_ip.ip_dst), mtu); 259 else 260 (void)snprintf(buf, sizeof buf, 261 "%s unreachable - need to frag", 262 ipaddr_string(&dp->icmp_ip.ip_dst)); 263 } 264 break; 265 266 default: 267 fmt = tok2str(unreach2str, "#%u %%s unreachable", 268 dp->icmp_code); 269 (void)snprintf(buf, sizeof buf, fmt, 270 ipaddr_string(&dp->icmp_ip.ip_dst)); 271 break; 272 } 273 break; 274 275 case ICMP_REDIRECT: 276 TCHECK(dp->icmp_ip.ip_dst); 277 fmt = tok2str(type2str, "redirect-#%u %%s to net %%s", 278 dp->icmp_code); 279 (void)snprintf(buf, sizeof buf, fmt, 280 ipaddr_string(&dp->icmp_ip.ip_dst), 281 ipaddr_string(&dp->icmp_gwaddr)); 282 break; 283 284 case ICMP_ROUTERADVERT: 285 { 286 const struct ih_rdiscovery *ihp; 287 const struct id_rdiscovery *idp; 288 u_int lifetime, num, size; 289 290 (void)strlcpy(buf, "router advertisement", sizeof(buf)); 291 292 ihp = (struct ih_rdiscovery *)&dp->icmp_void; 293 TCHECK(*ihp); 294 (void)strlcat(buf, " lifetime ", sizeof(buf)); 295 lifetime = EXTRACT_16BITS(&ihp->ird_lifetime); 296 if (lifetime < 60) 297 (void)snprintf(buf2, sizeof(buf2), "%u", lifetime); 298 else if (lifetime < 60 * 60) 299 (void)snprintf(buf2, sizeof(buf2), "%u:%02u", 300 lifetime / 60, lifetime % 60); 301 else 302 (void)snprintf(buf2, sizeof(buf2), "%u:%02u:%02u", 303 lifetime / 3600, (lifetime % 3600) / 60, 304 lifetime % 60); 305 strlcat(buf, buf2, sizeof(buf)); 306 307 num = ihp->ird_addrnum; 308 (void)snprintf(buf2, sizeof(buf2), " %u:", num); 309 strlcat(buf, buf2, sizeof(buf)); 310 311 size = ihp->ird_addrsiz; 312 if (size != 2) { 313 (void)snprintf(buf2, sizeof(buf2), " [size %u]", size); 314 strlcat(buf, buf2, sizeof(buf)); 315 break; 316 } 317 idp = (struct id_rdiscovery *)&dp->icmp_data; 318 while (num-- > 0) { 319 TCHECK(*idp); 320 (void)snprintf(buf2, sizeof(buf2), " {%s %u}", 321 ipaddr_string(&idp->ird_addr), 322 EXTRACT_32BITS(&idp->ird_pref)); 323 strlcat(buf, buf2, sizeof(buf)); 324 } 325 } 326 break; 327 328 case ICMP_TIMXCEED: 329 TCHECK(dp->icmp_ip.ip_dst); 330 switch (dp->icmp_code) { 331 332 case ICMP_TIMXCEED_INTRANS: 333 str = "time exceeded in-transit"; 334 break; 335 336 case ICMP_TIMXCEED_REASS: 337 str = "ip reassembly time exceeded"; 338 break; 339 340 default: 341 (void)snprintf(buf, sizeof buf, 342 "time exceeded-#%u", dp->icmp_code); 343 break; 344 } 345 break; 346 347 case ICMP_PARAMPROB: 348 switch (dp->icmp_code) { 349 case ICMP_PARAMPROB_OPTABSENT: 350 str = "requested option absent"; 351 break; 352 case ICMP_PARAMPROB_LENGTH: 353 snprintf(buf, sizeof buf, "bad length %u", dp->icmp_pptr); 354 break; 355 default: 356 TCHECK(dp->icmp_pptr); 357 (void)snprintf(buf, sizeof buf, 358 "parameter problem - octet %u", 359 dp->icmp_pptr); 360 break; 361 } 362 break; 363 364 case ICMP_MASKREPLY: 365 TCHECK(dp->icmp_mask); 366 (void)snprintf(buf, sizeof buf, "address mask is 0x%08x", 367 (u_int32_t)ntohl(dp->icmp_mask)); 368 break; 369 370 default: 371 str = tok2str(icmp2str, "type-#%u", dp->icmp_type); 372 break; 373 } 374 printf("icmp: %s", str); 375 if (vflag) { 376 if (TTEST2(dp->icmp_type, length)) { 377 u_int16_t sum, icmp_sum; 378 sum = in_cksum((const u_short *)dp, length, 0); 379 if (sum != 0) { 380 icmp_sum = EXTRACT_16BITS(&dp->icmp_cksum); 381 printf(" [bad icmp cksum %x! -> %x]", icmp_sum, 382 in_cksum_shouldbe(icmp_sum, sum)); 383 } 384 else 385 printf(" [icmp cksum ok]"); 386 } 387 } 388 if (vflag > 1 && !ICMP_INFOTYPE(dp->icmp_type) && 389 TTEST(dp->icmp_ip)) { 390 printf(" for "); 391 oip = &dp->icmp_ip; 392 ip_print((u_char *)oip, ntohs(oip->ip_len)); 393 } 394 return; 395 trunc: 396 printf("[|icmp]"); 397 } 398