| File: | src/usr.sbin/tcpdump/print-isoclns.c |
| Warning: | line 191, column 2 Value stored to 'li' is never read |
Press '?' to see keyboard shortcuts
Keyboard shortcuts:
| 1 | /* $OpenBSD: print-isoclns.c,v 1.15 2021/12/01 18:28:46 deraadt Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 1992, 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 | * Original code by Matt Thomas, Digital Equipment Corporation |
| 24 | */ |
| 25 | |
| 26 | #include <sys/types.h> |
| 27 | #include <sys/time.h> |
| 28 | #include <sys/socket.h> |
| 29 | |
| 30 | #include <net/if.h> |
| 31 | |
| 32 | #include <netinet/in.h> |
| 33 | #include <netinet/if_ether.h> |
| 34 | |
| 35 | #include <stdio.h> |
| 36 | |
| 37 | #include "interface.h" |
| 38 | #include "addrtoname.h" |
| 39 | #include "ethertype.h" |
| 40 | |
| 41 | #define CLNS129 129 |
| 42 | #define ESIS130 130 |
| 43 | #define ISIS131 131 |
| 44 | #define NULLNS0 0 |
| 45 | |
| 46 | static int osi_cksum(const u_char *, u_int, const u_char *, u_char *, u_char *); |
| 47 | static void esis_print(const u_char *, u_int); |
| 48 | |
| 49 | void |
| 50 | isoclns_print(const u_char *p, u_int length, u_int caplen, |
| 51 | const u_char *esrc, const u_char *edst) |
| 52 | { |
| 53 | if (caplen < 1) { |
| 54 | printf("[|iso-clns] "); |
| 55 | if (!eflag) |
| 56 | printf("%s > %s", |
| 57 | etheraddr_string(esrc), |
| 58 | etheraddr_string(edst)); |
| 59 | return; |
| 60 | } |
| 61 | |
| 62 | switch (*p) { |
| 63 | |
| 64 | case CLNS129: |
| 65 | /* esis_print(&p, &length); */ |
| 66 | printf("iso-clns"); |
| 67 | if (!eflag) |
| 68 | printf(" %s > %s", |
| 69 | etheraddr_string(esrc), |
| 70 | etheraddr_string(edst)); |
| 71 | break; |
| 72 | |
| 73 | case ESIS130: |
| 74 | printf("iso-esis"); |
| 75 | if (!eflag) |
| 76 | printf(" %s > %s", |
| 77 | etheraddr_string(esrc), |
| 78 | etheraddr_string(edst)); |
| 79 | esis_print(p, length); |
| 80 | return; |
| 81 | |
| 82 | case ISIS131: |
| 83 | printf("iso-isis"); |
| 84 | if (!eflag) |
| 85 | printf(" %s > %s", |
| 86 | etheraddr_string(esrc), |
| 87 | etheraddr_string(edst)); |
| 88 | /* isis_print(&p, &length); */ |
| 89 | printf(" len=%d ", length); |
| 90 | if (caplen > 1) |
| 91 | default_print_unaligned(p, caplen); |
| 92 | break; |
| 93 | |
| 94 | case NULLNS0: |
| 95 | printf("iso-nullns"); |
| 96 | if (!eflag) |
| 97 | printf(" %s > %s", |
| 98 | etheraddr_string(esrc), |
| 99 | etheraddr_string(edst)); |
| 100 | break; |
| 101 | |
| 102 | default: |
| 103 | printf("iso-clns %02x", p[0]); |
| 104 | if (!eflag) |
| 105 | printf(" %s > %s", |
| 106 | etheraddr_string(esrc), |
| 107 | etheraddr_string(edst)); |
| 108 | printf(" len=%d ", length); |
| 109 | if (caplen > 1) |
| 110 | default_print_unaligned(p, caplen); |
| 111 | break; |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | #define ESIS_REDIRECT6 6 |
| 116 | #define ESIS_ESH2 2 |
| 117 | #define ESIS_ISH4 4 |
| 118 | |
| 119 | struct esis_hdr { |
| 120 | u_char version; |
| 121 | u_char reserved; |
| 122 | u_char type; |
| 123 | u_char tmo[2]; |
| 124 | u_char cksum[2]; |
| 125 | }; |
| 126 | |
| 127 | static void |
| 128 | esis_print(const u_char *p, u_int length) |
| 129 | { |
| 130 | const u_char *ep; |
| 131 | int li = p[1]; |
| 132 | const struct esis_hdr *eh = (const struct esis_hdr *) &p[2]; |
| 133 | u_char cksum[2]; |
| 134 | u_char off[2]; |
| 135 | |
| 136 | if (length == 2) { |
| 137 | if (qflag) |
| 138 | printf(" bad pkt!"); |
| 139 | else |
| 140 | printf(" no header at all!"); |
| 141 | return; |
| 142 | } |
| 143 | ep = p + li; |
| 144 | if (li > length) { |
| 145 | if (qflag) |
| 146 | printf(" bad pkt!"); |
| 147 | else |
| 148 | printf(" LI(%d) > PDU size (%d)!", li, length); |
| 149 | return; |
| 150 | } |
| 151 | if (li < sizeof(struct esis_hdr) + 2) { |
| 152 | if (qflag) |
| 153 | printf(" bad pkt!"); |
| 154 | else { |
| 155 | printf(" too short for esis header %d:", li); |
| 156 | while (--length != 0) |
| 157 | printf("%02X", *p++); |
| 158 | } |
| 159 | return; |
| 160 | } |
| 161 | switch (eh->type & 0x1f) { |
| 162 | |
| 163 | case ESIS_REDIRECT6: |
| 164 | printf(" redirect"); |
| 165 | break; |
| 166 | |
| 167 | case ESIS_ESH2: |
| 168 | printf(" esh"); |
| 169 | break; |
| 170 | |
| 171 | case ESIS_ISH4: |
| 172 | printf(" ish"); |
| 173 | break; |
| 174 | |
| 175 | default: |
| 176 | printf(" type %d", eh->type & 0x1f); |
| 177 | break; |
| 178 | } |
| 179 | off[0] = eh->cksum[0]; |
| 180 | off[1] = eh->cksum[1]; |
| 181 | if (vflag && osi_cksum(p, li, eh->cksum, cksum, off)) { |
| 182 | printf(" bad cksum (got %02x%02x want %02x%02x)", |
| 183 | eh->cksum[1], eh->cksum[0], cksum[1], cksum[0]); |
| 184 | return; |
| 185 | } |
| 186 | if (eh->version != 1) { |
| 187 | printf(" unsupported version %d", eh->version); |
| 188 | return; |
| 189 | } |
| 190 | p += sizeof(*eh) + 2; |
| 191 | li -= sizeof(*eh) + 2; /* protoid * li */ |
Value stored to 'li' is never read | |
| 192 | |
| 193 | switch (eh->type & 0x1f) { |
| 194 | case ESIS_REDIRECT6: { |
| 195 | const u_char *dst, *snpa, *is; |
| 196 | |
| 197 | dst = p; p += *p + 1; |
| 198 | if (p > snapend) |
| 199 | return; |
| 200 | printf(" %s", isonsap_string(dst)); |
| 201 | snpa = p; p += *p + 1; |
| 202 | is = p; p += *p + 1; |
| 203 | if (p > snapend) |
| 204 | return; |
| 205 | if (p > ep) { |
| 206 | printf(" [bad li]"); |
| 207 | return; |
| 208 | } |
| 209 | if (is[0] == 0) |
| 210 | printf(" > %s", etheraddr_string(&snpa[1])); |
| 211 | else |
| 212 | printf(" > %s", isonsap_string(is)); |
| 213 | li = ep - p; |
| 214 | break; |
| 215 | } |
| 216 | case ESIS_ESH2: { |
| 217 | const u_char *nsap; |
| 218 | int i, nnsaps; |
| 219 | |
| 220 | nnsaps = *p++; |
| 221 | |
| 222 | /* print NSAPs */ |
| 223 | for (i = 0; i < nnsaps; i++) { |
| 224 | nsap = p; |
| 225 | p += *p + 1; |
| 226 | if (p > ep) { |
| 227 | printf(" [bad li]"); |
| 228 | return; |
| 229 | } |
| 230 | if (p > snapend) |
| 231 | return; |
| 232 | printf(" nsap %s", isonsap_string(nsap)); |
| 233 | } |
| 234 | li = ep - p; |
| 235 | break; |
| 236 | } |
| 237 | case ESIS_ISH4: { |
| 238 | const u_char *is; |
| 239 | |
| 240 | is = p; p += *p + 1; |
| 241 | if (p > ep) { |
| 242 | printf(" [bad li]"); |
| 243 | return; |
| 244 | } |
| 245 | if (p > snapend) |
| 246 | return; |
| 247 | printf(" net %s", isonsap_string(is)); |
| 248 | li = ep - p; |
| 249 | break; |
| 250 | } |
| 251 | |
| 252 | default: |
| 253 | printf(" len=%d", length); |
| 254 | if (length && p < snapend) { |
| 255 | length = snapend - p; |
| 256 | default_print(p, length); |
| 257 | } |
| 258 | return; |
| 259 | } |
| 260 | if (vflag) |
| 261 | while (p < ep && li) { |
| 262 | int op, opli; |
| 263 | const u_char *q; |
| 264 | |
| 265 | if (snapend - p < 2) |
| 266 | return; |
| 267 | if (li < 2) { |
| 268 | printf(" bad opts/li"); |
| 269 | return; |
| 270 | } |
| 271 | op = *p++; |
| 272 | opli = *p++; |
| 273 | li -= 2; |
| 274 | if (opli > li) { |
| 275 | printf(" opt (%d) too long", op); |
| 276 | return; |
| 277 | } |
| 278 | li -= opli; |
| 279 | q = p; |
| 280 | p += opli; |
| 281 | if (snapend < p) |
| 282 | return; |
| 283 | if (op == 198 && opli == 2) { |
| 284 | printf(" tmo=%d", q[0] * 256 + q[1]); |
| 285 | continue; |
| 286 | } |
| 287 | printf (" %d:<", op); |
| 288 | while (--opli >= 0) |
| 289 | printf("%02x", *q++); |
| 290 | printf (">"); |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | static int |
| 295 | osi_cksum(const u_char *p, u_int len, |
| 296 | const u_char *toff, u_char *cksum, u_char *off) |
| 297 | { |
| 298 | const u_char *ep; |
| 299 | int c0, c1; |
| 300 | int n; |
| 301 | |
| 302 | if ((cksum[0] = off[0]) == 0 && (cksum[1] = off[1]) == 0) |
| 303 | return 0; |
| 304 | |
| 305 | n = toff - p + 1; |
| 306 | c0 = c1 = 0; |
| 307 | ep = p + len; |
| 308 | for (; p < toff; p++) { |
| 309 | c0 = (c0 + *p); |
| 310 | c1 += c0; |
| 311 | } |
| 312 | |
| 313 | /* skip cksum bytes */ |
| 314 | p += 2; |
| 315 | c1 += c0; c1 += c0; |
| 316 | |
| 317 | for (; p < ep; p++) { |
| 318 | c0 = (c0 + *p); |
| 319 | c1 += c0; |
| 320 | } |
| 321 | |
| 322 | c1 = (((c0 * (len - n)) - c1) % 255); |
| 323 | cksum[0] = (u_char) ((c1 < 0) ? c1 + 255 : c1); |
| 324 | c1 = (-(int) (c1 + c0)) % 255; |
| 325 | cksum[1] = (u_char) (c1 < 0 ? c1 + 255 : c1); |
| 326 | |
| 327 | return (off[0] != cksum[0] || off[1] != cksum[1]); |
| 328 | } |