Return to pim_util.c CVS log

Up to [ELWIX - Embedded LightWeight unIX -] / embedaddon / quagga / pimd

quagga 1.0.20160315

    1: /*
    2:   PIM for Quagga
    3:   Copyright (C) 2008  Everton da Silva Marques
    4: 
    5:   This program is free software; you can redistribute it and/or modify
    6:   it under the terms of the GNU General Public License as published by
    7:   the Free Software Foundation; either version 2 of the License, or
    8:   (at your option) any later version.
    9: 
   10:   This program is distributed in the hope that it will be useful, but
   11:   WITHOUT ANY WARRANTY; without even the implied warranty of
   12:   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   13:   General Public License for more details.
   14:   
   15:   You should have received a copy of the GNU General Public License
   16:   along with this program; see the file COPYING; if not, write to the
   17:   Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
   18:   MA 02110-1301 USA
   19:   
   20:   $QuaggaId: $Format:%an, %ai, %h$ $
   21: */
   22: 
   23: #include <zebra.h>
   24: 
   25: #include "log.h"
   26: 
   27: #include "pim_util.h"
   28: 
   29: /*
   30:   RFC 3376: 4.1.7. QQIC (Querier's Query Interval Code)
   31:   
   32:   If QQIC < 128,  QQI = QQIC
   33:   If QQIC >= 128, QQI = (mant | 0x10) << (exp + 3)
   34:   
   35:   0 1 2 3 4 5 6 7
   36:   +-+-+-+-+-+-+-+-+
   37:   |1| exp | mant  |
   38:   +-+-+-+-+-+-+-+-+
   39:   
   40:   Since exp=0..7 then (exp+3)=3..10, then QQI has
   41:   one of the following bit patterns:
   42:   
   43:   exp=0: QQI = 0000.0000.1MMM.M000
   44:   exp=1: QQI = 0000.0001.MMMM.0000
   45:   ...
   46:   exp=6: QQI = 001M.MMM0.0000.0000
   47:   exp=7: QQI = 01MM.MM00.0000.0000
   48:   --------- ---------
   49:   0x4  0x0  0x0  0x0
   50: */
   51: uint8_t igmp_msg_encode16to8(uint16_t value)
   52: {
   53:   uint8_t code;
   54: 
   55:   if (value < 128) {
   56:     code = value;
   57:   }
   58:   else {
   59:     uint16_t mask = 0x4000;
   60:     uint8_t  exp;
   61:     uint16_t mant;
   62:     for (exp = 7; exp > 0; --exp) {
   63:       if (mask & value)
   64: 	break;
   65:       mask >>= 1;
   66:     }
   67:     mant = 0x000F & (value >> (exp + 3));
   68:     code = ((uint8_t) 1 << 7) | ((uint8_t) exp << 4) | (uint8_t) mant;
   69:   }
   70: 
   71:   return code;
   72: }
   73: 
   74: /*
   75:   RFC 3376: 4.1.7. QQIC (Querier's Query Interval Code)
   76:   
   77:   If QQIC < 128,  QQI = QQIC
   78:   If QQIC >= 128, QQI = (mant | 0x10) << (exp + 3)
   79:   
   80:   0 1 2 3 4 5 6 7
   81:   +-+-+-+-+-+-+-+-+
   82:   |1| exp | mant  |
   83:   +-+-+-+-+-+-+-+-+
   84: */
   85: uint16_t igmp_msg_decode8to16(uint8_t code)
   86: {
   87:   uint16_t value;
   88: 
   89:   if (code < 128) {
   90:     value = code;
   91:   }
   92:   else {
   93:     uint16_t mant = (code & 0x0F);
   94:     uint8_t  exp  = (code & 0x70) >> 4;
   95:     value = (mant | 0x10) << (exp + 3);
   96:   }
   97: 
   98:   return value;
   99: }
  100: 
  101: void pim_pkt_dump(const char *label, const uint8_t *buf, int size)
  102: {
  103:   char dump_buf[1000];
  104:   int i = 0;
  105:   int j = 0;
  106: 
  107:   for (; i < size; ++i, j += 2) {
  108:     int left = sizeof(dump_buf) - j;
  109:     if (left < 4) {
  110:       if (left > 1) {
  111: 	strcat(dump_buf + j, "!"); /* mark as truncated */
  112:       }
  113:       break;
  114:     }
  115:     snprintf(dump_buf + j, left, "%02x", buf[i]);
  116:   }
  117: 
  118:   zlog_debug("%s: pkt dump size=%d: %s",
  119: 	     label,
  120: 	     size,
  121: 	     dump_buf);
  122: }