The Tcpdump Group git mirrors - tcpdump/blob - print-stp.c

   1 /*
   2  * Copyright (c) 2000 Lennert Buytenhek
   3  *
   4  * This software may be distributed either under the terms of the
   5  * BSD-style license that accompanies tcpdump or the GNU General
   6  * Public License
   7  *
   8  * Format and print IEEE 802.1d spanning tree protocol packets.
   9  * Contributed by Lennert Buytenhek <buytenh@gnu.org>
  10  */
  11
  12 #ifndef lint
  13 static const char rcsid[] =
  14     "@(#) $Header: /tcpdump/master/tcpdump/print-stp.c,v 1.2 2000-06-13 12:19:07 assar Exp $";
  15 #endif
  16
  17 #ifdef HAVE_CONFIG_H
  18 #include "config.h"
  19 #endif
  20
  21 #include <sys/param.h>
  22 #include <sys/time.h>
  23 #include <sys/socket.h>
  24
  25 #include <netinet/in.h>
  26 #include <netinet/in_systm.h>
  27 #include <netinet/ip.h>
  28 #include <netinet/ip_var.h>
  29 #include <netinet/udp.h>
  30 #include <netinet/udp_var.h>
  31 #include <netinet/tcp.h>
  32 #include <netinet/tcpip.h>
  33
  34 #ifdef __STDC__
  35 #include <stdlib.h>
  36 #endif
  37 #include <stdio.h>
  38 #include <string.h>
  39
  40 #include "interface.h"
  41 #include "addrtoname.h"
  42 #include "extract.h"
  43
  44 static void
  45 stp_print_bridge_id(const u_char *p)
  46 {
  47         printf("%.2x%.2x.%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
  48                p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]);
  49 }
  50
  51 static void
  52 stp_print_config_bpdu(const u_char *p, u_int length)
  53 {
  54         printf("config ");
  55         if (p[7] & 1)
  56                 printf("TOP_CHANGE ");
  57         if (p[7] & 0x80)
  58                 printf("TOP_CHANGE_ACK ");
  59
  60         stp_print_bridge_id(p+20);
  61         printf(".%.2x%.2x ", p[28], p[29]);
  62
  63         printf("root ");
  64         stp_print_bridge_id(p+8);
  65
  66         printf(" pathcost %i ", (p[16] << 24) | (p[17] << 16) | (p[18] << 8) | p[19]);
  67
  68         printf("age %i ", p[30]);
  69         printf("max %i ", p[32]);
  70         printf("hello %i ", p[34]);
  71         printf("fdelay %i ", p[36]);
  72 }
  73
  74 static void
  75 stp_print_tcn_bpdu(const u_char *p, u_int length)
  76 {
  77         printf("tcn");
  78 }
  79
  80 /*
  81  * Print 802.1d packets.
  82  */
  83 void
  84 stp_print(const u_char *p, u_int length)
  85 {
  86         if (length < 7)
  87                 goto trunc;
  88
  89         printf("802.1d ");
  90         if (p[2] != 0x03 || p[3] || p[4] || p[5]) {
  91                 printf("unknown version");
  92                 return;
  93         }
  94
  95         switch (p[6])
  96         {
  97         case 0:
  98                 if (length < 10)
  99                         goto trunc;
 100                 stp_print_config_bpdu(p, length);
 101                 break;
 102
 103         case 1:
 104                 stp_print_tcn_bpdu(p, length);
 105                 break;
 106
 107         default:
 108                 printf("unknown type %i\n", p[6]);
 109                 break;
 110         }
 111
 112         return;
 113 trunc:
 114         printf("[|stp %d]", length);
 115 }