src/icmp/Icmp.h

   1 /*
   2  * $Id: ICMP.h,v 1.1 2007/12/14 23:11:45 amosjeffries Exp $
   3  *
   4  * DEBUG: section 37    ICMP Routines
   5  * AUTHOR: Duane Wessels, Amos Jeffries
   6  *
   7  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   8  * ----------------------------------------------------------
   9  *
  10  *  Squid is the result of efforts by numerous individuals from
  11  *  the Internet community; see the CONTRIBUTORS file for full
  12  *  details.   Many organizations have provided support for Squid's
  13  *  development; see the SPONSORS file for full details.  Squid is
  14  *  Copyrighted (C) 2001 by the Regents of the University of
  15  *  California; see the COPYRIGHT file for full details.  Squid
  16  *  incorporates software developed and/or copyrighted by other
  17  *  sources; see the CREDITS file for full details.
  18  *
  19  *  This program is free software; you can redistribute it and/or modify
  20  *  it under the terms of the GNU General Public License as published by
  21  *  the Free Software Foundation; either version 2 of the License, or
  22  *  (at your option) any later version.
  23  *
  24  *  This program is distributed in the hope that it will be useful,
  25  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  *  GNU General Public License for more details.
  28  *
  29  *  You should have received a copy of the GNU General Public License
  30  *  along with this program; if not, write to the Free Software
  31  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  32  *
  33  */
  34 #ifndef _INCLUDE_ICMP_H
  35 #define _INCLUDE_ICMP_H
  36
  37 #include "config.h"
  38 #include "IpAddress.h"
  39
  40 #define PINGER_PAYLOAD_SZ       8192
  41
  42 #define MAX_PAYLOAD 256 // WAS: SQUIDHOSTNAMELEN
  43 #define MAX_PKT4_SZ (MAX_PAYLOAD + sizeof(struct timeval) + sizeof (char) + sizeof(struct icmphdr) + 1)
  44 #if USE_IPV6
  45 #define MAX_PKT6_SZ (MAX_PAYLOAD + sizeof(struct timeval) + sizeof (char) + sizeof(struct icmp6_hdr) + 1)
  46 #endif
  47
  48 #if USE_ICMP
  49
  50 /* This is a line-data format struct. DO NOT alter. */
  51 struct pingerEchoData {
  52     IpAddress to;
  53     unsigned char opcode;
  54     int psize;
  55     char payload[PINGER_PAYLOAD_SZ];
  56 };
  57
  58 /* This is a line-data format struct. DO NOT alter. */
  59 struct pingerReplyData {
  60     IpAddress from;
  61     unsigned char opcode;
  62     int rtt;
  63     int hops;
  64     int psize;
  65     char payload[PINGER_PAYLOAD_SZ];
  66 };
  67
  68 struct icmpEchoData {
  69     struct timeval tv;
  70     unsigned char opcode;
  71     char payload[MAX_PAYLOAD];
  72 };
  73
  74 SQUIDCEXTERN int icmp_pkts_sent;
  75
  76 #endif /* USE_ICMP */
  77
  78
  79 /**
  80  * Implements the squid interface to access ICMP operations
  81  *
  82  \par
  83  * Child implementations define specific parts of these operations
  84  * using these methods as a naming and parameter template.
  85  *
  86  * IcmpSquid - implements the squid side of squid-pinger interface
  87  * IcmpPinger - implements the pinger side of the squid-pinger interface
  88  * Icmpv4 - implements pinger helper for Icmpv4
  89  * Icmpv6 - implements pinger helper for Icmpv6
  90  */
  91 class Icmp
  92 {
  93 public:
  94     Icmp();
  95     virtual ~Icmp() {};
  96
  97     /// Start pinger helper and initiate control channel
  98     virtual int Open() =0;
  99
 100     /// Shutdown pinger helper and control channel
 101     virtual void Close();
 102
 103 #if USE_ICMP
 104
 105     /**
 106      * Construct and Send an ECHO request
 107      *
 108      \param to        Destination address being 'pinged'
 109      \param opcode    Specific code for ECHO request, see RFC ????.
 110      \param payload   A payload MAY be sent in the ICMP message.
 111      *                Content longer than MAX_PAYLOAD will be truncated.
 112      \param len       Length of the payload in bytes if any is to be sent or 0.
 113      */
 114     virtual void SendEcho(IpAddress &to, int opcode, const char *payload=NULL, int len=0) =0;
 115
 116     /// Handle ICMP responses.
 117     virtual void Recv(void) =0;
 118
 119 protected:
 120     /* shared internal methods */
 121
 122     /// Calculate a packet checksum
 123     int CheckSum(unsigned short *ptr, int size);
 124
 125     /**
 126      * Translate TTL to a hop distance
 127      *
 128      \param ttl negative     : n > 33
 129      \param ttl n(0...32)    : 32 >= n >= 1
 130      \param ttl n(33...62)   : 32 >= n >= 1
 131      \param ttl n(63...64)   : 2 >= n >= 1
 132      \param ttl n(65...128)  : 64 >= n >= 1
 133      \param ttl n(129...192) : 64 >= n >= 1
 134      \param ttl n(193...)    : n < 255
 135      *
 136      \bug BUG? ttl<0 can produce high hop values
 137      \bug BUG? ttl>255 can produce zero or negative hop values
 138      */
 139     int ipHops(int ttl);
 140
 141     /// Log the packet.
 142     void Log(const IpAddress &addr, const u_int8_t type, const char* pkt_str, const int rtt, const int hops);
 143
 144     /* no use wasting memory */
 145     int icmp_sock;
 146     int icmp_ident;
 147 #endif /* USE_ICMP */
 148 };
 149
 150 #endif