1 /* $OpenBSD: print-dvmrp.c,v 1.6 2009/10/27 23:59:55 deraadt Exp $ */ 2 3 /* 4 * Copyright (c) 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/param.h> 25 #include <sys/time.h> 26 #include <sys/socket.h> 27 28 #include <netinet/in.h> 29 #include <netinet/in_systm.h> 30 #include <netinet/ip.h> 31 #include <netinet/ip_var.h> 32 #include <netinet/udp.h> 33 #include <netinet/udp_var.h> 34 #include <netinet/tcp.h> 35 36 #include <stdio.h> 37 #include <string.h> 38 #include <stdlib.h> 39 #include <unistd.h> 40 41 #include "interface.h" 42 #include "addrtoname.h" 43 44 /* 45 * DVMRP message types and flag values shamelessly stolen from 46 * mrouted/dvmrp.h. 47 */ 48 #define DVMRP_PROBE 1 /* for finding neighbors */ 49 #define DVMRP_REPORT 2 /* for reporting some or all routes */ 50 #define DVMRP_ASK_NEIGHBORS 3 /* sent by mapper, asking for a list */ 51 /* 52 * of this router's neighbors 53 */ 54 #define DVMRP_NEIGHBORS 4 /* response to such a request */ 55 #define DVMRP_ASK_NEIGHBORS2 5 /* as above, want new format reply */ 56 #define DVMRP_NEIGHBORS2 6 57 #define DVMRP_PRUNE 7 /* prune message */ 58 #define DVMRP_GRAFT 8 /* graft message */ 59 #define DVMRP_GRAFT_ACK 9 /* graft acknowledgement */ 60 61 /* 62 * 'flags' byte values in DVMRP_NEIGHBORS2 reply. 63 */ 64 #define DVMRP_NF_TUNNEL 0x01 /* neighbors reached via tunnel */ 65 #define DVMRP_NF_SRCRT 0x02 /* tunnel uses IP source routing */ 66 #define DVMRP_NF_DOWN 0x10 /* kernel state of interface */ 67 #define DVMRP_NF_DISABLED 0x20 /* administratively disabled */ 68 #define DVMRP_NF_QUERIER 0x40 /* I am the subnet's querier */ 69 70 static void print_probe(const u_char *, const u_char *, u_int); 71 static void print_report(const u_char *, const u_char *, u_int); 72 static void print_neighbors(const u_char *, const u_char *, u_int); 73 static void print_neighbors2(const u_char *, const u_char *, u_int); 74 static void print_prune(const u_char *, const u_char *, u_int); 75 static void print_graft(const u_char *, const u_char *, u_int); 76 static void print_graft_ack(const u_char *, const u_char *, u_int); 77 78 static u_int32_t target_level; 79 80 void 81 dvmrp_print(register const u_char *bp, register u_int len) 82 { 83 register const u_char *ep; 84 register u_char type; 85 86 ep = (const u_char *)snapend; 87 if (bp >= ep) 88 return; 89 90 type = bp[1]; 91 bp += 8; 92 /* 93 * Skip IGMP header 94 */ 95 96 len -= 8; 97 98 switch (type) { 99 100 case DVMRP_PROBE: 101 printf(" Probe"); 102 if (vflag) 103 print_probe(bp, ep, len); 104 break; 105 106 case DVMRP_REPORT: 107 printf(" Report"); 108 if (vflag) 109 print_report(bp, ep, len); 110 break; 111 112 case DVMRP_ASK_NEIGHBORS: 113 printf(" Ask-neighbors(old)"); 114 break; 115 116 case DVMRP_NEIGHBORS: 117 printf(" Neighbors(old)"); 118 print_neighbors(bp, ep, len); 119 break; 120 121 case DVMRP_ASK_NEIGHBORS2: 122 printf(" Ask-neighbors2"); 123 break; 124 125 case DVMRP_NEIGHBORS2: 126 printf(" Neighbors2"); 127 /* 128 * extract version and capabilities from IGMP group 129 * address field 130 */ 131 bp -= 4; 132 target_level = (bp[0] << 24) | (bp[1] << 16) | 133 (bp[2] << 8) | bp[3]; 134 bp += 4; 135 print_neighbors2(bp, ep, len); 136 break; 137 138 case DVMRP_PRUNE: 139 printf(" Prune"); 140 print_prune(bp, ep, len); 141 break; 142 143 case DVMRP_GRAFT: 144 printf(" Graft"); 145 print_graft(bp, ep, len); 146 break; 147 148 case DVMRP_GRAFT_ACK: 149 printf(" Graft-ACK"); 150 print_graft_ack(bp, ep, len); 151 break; 152 153 default: 154 printf(" [type %d]", type); 155 break; 156 } 157 } 158 159 static void 160 print_report(register const u_char *bp, register const u_char *ep, 161 register u_int len) 162 { 163 register u_int32_t mask, origin; 164 register int metric, i, width, done; 165 166 while (len > 0) { 167 if (len < 3) { 168 printf(" [|]"); 169 return; 170 } 171 mask = (u_int32_t)0xff << 24 | bp[0] << 16 | bp[1] << 8 | bp[2]; 172 width = 1; 173 if (bp[0]) 174 width = 2; 175 if (bp[1]) 176 width = 3; 177 if (bp[2]) 178 width = 4; 179 180 printf("\n\tMask %s", intoa(htonl(mask))); 181 bp += 3; 182 len -= 3; 183 do { 184 if (bp + width + 1 > ep) { 185 printf(" [|]"); 186 return; 187 } 188 if (len < width + 1) { 189 printf("\n\t [Truncated Report]"); 190 return; 191 } 192 origin = 0; 193 for (i = 0; i < width; ++i) 194 origin = origin << 8 | *bp++; 195 for ( ; i < 4; ++i) 196 origin <<= 8; 197 198 metric = *bp++; 199 done = metric & 0x80; 200 metric &= 0x7f; 201 printf("\n\t %s metric %d", intoa(htonl(origin)), 202 metric); 203 len -= width + 1; 204 } while (!done); 205 } 206 } 207 208 #define GET_ADDR(to) (memcpy((char *)to, (char *)bp, 4), bp += 4) 209 210 static void 211 print_probe(register const u_char *bp, register const u_char *ep, 212 register u_int len) 213 { 214 register u_int32_t genid; 215 u_char neighbor[4]; 216 217 if ((len < 4) || ((bp + 4) > ep)) { 218 /* { (ctags) */ 219 printf(" [|}"); 220 return; 221 } 222 genid = (bp[0] << 24) | (bp[1] << 16) | (bp[2] << 8) | bp[3]; 223 bp += 4; 224 len -= 4; 225 printf("\n\tgenid %u", genid); 226 227 while ((len > 0) && (bp < ep)) { 228 if ((len < 4) || ((bp + 4) > ep)) { 229 printf(" [|]"); 230 return; 231 } 232 GET_ADDR(neighbor); 233 len -= 4; 234 printf("\n\tneighbor %s", ipaddr_string(neighbor)); 235 } 236 } 237 238 static void 239 print_neighbors(register const u_char *bp, register const u_char *ep, 240 register u_int len) 241 { 242 u_char laddr[4], neighbor[4]; 243 register u_char metric; 244 register u_char thresh; 245 register int ncount; 246 247 while (len > 0 && bp < ep) { 248 if (len < 7 || (bp + 7) >= ep) { 249 printf(" [|]"); 250 return; 251 } 252 GET_ADDR(laddr); 253 metric = *bp++; 254 thresh = *bp++; 255 ncount = *bp++; 256 len -= 7; 257 while (--ncount >= 0 && (len >= 4) && (bp + 4) < ep) { 258 GET_ADDR(neighbor); 259 printf(" [%s ->", ipaddr_string(laddr)); 260 printf(" %s, (%d/%d)]", 261 ipaddr_string(neighbor), metric, thresh); 262 len -= 4; 263 } 264 } 265 } 266 267 static void 268 print_neighbors2(register const u_char *bp, register const u_char *ep, 269 register u_int len) 270 { 271 u_char laddr[4], neighbor[4]; 272 register u_char metric, thresh, flags; 273 register int ncount; 274 275 printf(" (v %d.%d):", 276 (int)target_level & 0xff, 277 (int)(target_level >> 8) & 0xff); 278 279 while (len > 0 && bp < ep) { 280 if (len < 8 || (bp + 8) >= ep) { 281 printf(" [|]"); 282 return; 283 } 284 GET_ADDR(laddr); 285 metric = *bp++; 286 thresh = *bp++; 287 flags = *bp++; 288 ncount = *bp++; 289 len -= 8; 290 while (--ncount >= 0 && (len >= 4) && (bp + 4) <= ep) { 291 GET_ADDR(neighbor); 292 printf(" [%s -> ", ipaddr_string(laddr)); 293 printf("%s (%d/%d", ipaddr_string(neighbor), 294 metric, thresh); 295 if (flags & DVMRP_NF_TUNNEL) 296 printf("/tunnel"); 297 if (flags & DVMRP_NF_SRCRT) 298 printf("/srcrt"); 299 if (flags & DVMRP_NF_QUERIER) 300 printf("/querier"); 301 if (flags & DVMRP_NF_DISABLED) 302 printf("/disabled"); 303 if (flags & DVMRP_NF_DOWN) 304 printf("/down"); 305 printf(")]"); 306 len -= 4; 307 } 308 if (ncount != -1) { 309 printf(" [|]"); 310 return; 311 } 312 } 313 } 314 315 static void 316 print_prune(register const u_char *bp, register const u_char *ep, 317 register u_int len) 318 { 319 union a { 320 u_char b[4]; 321 u_int32_t i; 322 } prune_timer; 323 324 if (len < 12 || (bp + 12) > ep) { 325 printf(" [|]"); 326 return; 327 } 328 printf(" src %s grp %s", ipaddr_string(bp), ipaddr_string(bp + 4)); 329 bp += 8; 330 GET_ADDR(prune_timer.b); 331 printf(" timer %d", (int)ntohl(prune_timer.i)); 332 } 333 334 static void 335 print_graft(register const u_char *bp, register const u_char *ep, 336 register u_int len) 337 { 338 339 if (len < 8 || (bp + 8) > ep) { 340 printf(" [|]"); 341 return; 342 } 343 printf(" src %s grp %s", ipaddr_string(bp), ipaddr_string(bp + 4)); 344 } 345 346 static void 347 print_graft_ack(register const u_char *bp, register const u_char *ep, 348 register u_int len) 349 { 350 351 if (len < 8 || (bp + 8) > ep) { 352 printf(" [|]"); 353 return; 354 } 355 printf(" src %s grp %s", ipaddr_string(bp), ipaddr_string(bp + 4)); 356 } 357