ecnprobe/support.c

   1 /*
   2  Copyright (c) 2000
   3  International Computer Science Institute
   4  All rights reserved.
   5
   6  This file may contain software code originally developed for the
   7  Sting project. The Sting software carries the following copyright:
   8
   9  Copyright (c) 1998, 1999
  10  Stefan Savage and the University of Washington.
  11  All rights reserved.
  12
  13  Redistribution and use in source and binary forms, with or without
  14  modification, are permitted provided that the following conditions
  15  are met:
  16  1. Redistributions of source code must retain the above copyright
  17     notice, this list of conditions and the following disclaimer.
  18  2. Redistributions in binary form must reproduce the above copyright
  19     notice, this list of conditions and the following disclaimer in the
  20     documentation and/or other materials provided with the distribution.
  21  3. All advertising materials mentioning features or use of this software
  22     must display the following acknowledgment:
  23       This product includes software developed by ACIRI, the AT&T
  24       Center for Internet Research at ICSI (the International Computer
  25       Science Institute). This product may also include software developed
  26       by Stefan Savage at the University of Washington.
  27  4. The names of ACIRI, ICSI, Stefan Savage and University of Washington
  28     may not be used to endorse or promote products derived from this software
  29     without specific prior written permission.
  30
  31  THIS SOFTWARE IS PROVIDED BY ICSI AND CONTRIBUTORS ``AS IS'' AND
  32  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  33  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  34  ARE DISCLAIMED.  IN NO EVENT SHALL ICSI OR CONTRIBUTORS BE LIABLE
  35  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  39  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  40  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  41  SUCH DAMAGE.
  42 */
  43 #include <sys/types.h>
  44 #include <sys/param.h>
  45 #include <sys/time.h>
  46 #include <string.h>
  47 #include <stdio.h>
  48 #include <unistd.h>
  49 #include "base.h"
  50 #include "inet.h"
  51 #include "session.h"
  52 #include "capture.h"
  53 #include "support.h"
  54
  55 extern struct TcpSession session;
  56
  57 void SendReset()
  58 {
  59   struct IPPacket *p;
  60   int i;
  61
  62   if (session.dont_send_reset)
  63           return;
  64
  65   if ((p = (struct IPPacket *)calloc(1, sizeof(struct IPPacket))) == NULL) {
  66     perror("ERROR: Could not allocate RST packet:") ;
  67     Quit(ERR_MEM_ALLOC) ;
  68   }
  69
  70   if ((p->ip = (struct IpHeader *)calloc(1, sizeof(struct IpHeader))) == NULL) {
  71     perror("ERROR: Could not allocate IP Header for RST packet:") ;
  72     Quit(ERR_MEM_ALLOC) ;
  73   }
  74
  75   if ((p->tcp = (struct TcpHeader *)calloc(1, sizeof(struct TcpHeader))) == NULL) {
  76     perror("ERROR: Could not allocate TCP Header for RST packet:") ;
  77     Quit(ERR_MEM_ALLOC) ;
  78   }
  79
  80   for (i = 0; i < MAXRESETRETRANSMITS; i++) {
  81     SendSessionPacket(p,
  82                       //sizeof(struct IPPacket),
  83                       sizeof(struct IpHeader) + sizeof(struct TcpHeader),
  84                       TCPFLAGS_RST,
  85                       0,
  86                       0,
  87                       0);
  88   }
  89
  90 /*  free(p->ip);
  91   free(p->tcp);
  92   free(p);
  93 */
  94
  95 }
  96
  97 #if 0
  98 /* make a clean exit on interrupts */
  99 void  SigHandle (int signo)
 100 {
 101   Cleanup () ;
 102   fflush(stdout);
 103   fflush(stderr);
 104   exit(-1);
 105 }
 106
 107
 108 void Cleanup()
 109 {
 110
 111   char ipfw_rule[100];
 112   int r;
 113
 114   /* If a firewall rule has been installed then remove it */
 115   if (session.initFirewall > 0) {
 116
 117 #ifdef linux
 118 #define IP_FW_DEL       (IP_FW_DELETE)
 119 #endif /* linux */
 120
 121     sprintf(ipfw_rule, "ipfw del 00%d", session.firewall_rule_number);
 122     r = system(ipfw_rule);
 123
 124   }
 125
 126   if (session.initSession > 0) {
 127
 128     SendReset();
 129     shutdown(session.socket,2);
 130
 131   }
 132
 133   if (session.initCapture > 0) {
 134     CaptureEnd();
 135   }
 136
 137 }
 138
 139 void Quit(int how)
 140 {
 141
 142   Cleanup();
 143   fflush(stdout);
 144   fflush(stderr);
 145   exit(how);
 146
 147 }
 148 #endif /* 0 */
 149
 150 double GetTime()
 151 {
 152   struct timeval tv;
 153   struct timezone tz;
 154   double postEpochSecs;
 155
 156   if (gettimeofday(&tv, &tz) < 0) {
 157     perror("GetTime");
 158     exit(-1);
 159   }
 160
 161   postEpochSecs = (double)tv.tv_sec + ((double)tv.tv_usec/(double)1000000.0);
 162   return postEpochSecs;
 163 }
 164
 165 double GetTimeMicroSeconds()
 166 {
 167   struct timeval tv;
 168   struct timezone tz;
 169   double postEpochMicroSecs;
 170
 171   if (gettimeofday(&tv, &tz) < 0) {
 172     perror("GetTimeMicroSeconds");
 173     exit(-1);
 174   }
 175
 176   postEpochMicroSecs = (double)tv.tv_sec * 1000000 + (double)tv.tv_usec;
 177   return postEpochMicroSecs;
 178
 179 }
 180
 181 void PrintTimeStamp(struct timeval *ts)
 182 {
 183   (void)printf("%02d:%02d:%02d.%06u ",
 184                (unsigned int)ts->tv_sec / 3600,
 185                ((unsigned int)ts->tv_sec % 3600) / 60,
 186                (unsigned int)ts->tv_sec % 60, (unsigned int)ts->tv_usec);
 187 }
 188
 189 void processBadPacket (struct IPPacket *p)
 190 {
 191
 192   if (session.debug == SESSION_DEBUG_HIGH) {
 193     printf("In ProcessBadPacket...\n");
 194   }
 195   /*
 196    * reset? the other guy does not like us?
 197    */
 198   if (INSESSION(p,session.dst,session.dport,session.src,session.sport) && (p->tcp->tcp_flags & TCPFLAGS_RST)) {
 199     printf("ERROR: EARLY_RST.\nRETURN CODE: %d\n", EARLY_RST);
 200     Quit(EARLY_RST);
 201   }
 202   /*
 203    * some other packet between us that is none of the above
 204    */
 205   if (INSESSION(p, session.src, session.sport, session.dst, session.dport) ||
 206       INSESSION(p, session.dst, session.dport, session.src, session.sport)) {
 207
 208     printf("ERROR: Unexpected packet\nRETURN CODE: %d\n", UNEXPECTED_PKT);
 209     printf("Expecting:\n");
 210     printf("\tsrc = %s:%d (seq=%u, ack=%u)\n",
 211            InetAddress(session.src), session.sport,
 212            session.snd_nxt-session.iss,
 213            session.rcv_nxt-session.irs);
 214     printf("\tdst = %s:%d (seq=%u, ack=%u)\n",
 215            InetAddress(session.dst),session.dport,
 216            session.rcv_nxt-session.irs, session.snd_una-session.iss);
 217     printf("Received:\n\t");
 218     PrintTcpPacket(p);
 219     printf ("session.snd_nxt=%d, session.rcv_nxt=%d, session.snd_una=%d\n",
 220             session.snd_nxt-session.iss, session.rcv_nxt-session.irs, session.snd_una-session.iss);
 221     Quit(UNEXPECTED_PKT);
 222   }
 223   /*
 224    * none of the above,
 225    * so we must be seeing packets
 226    * from some other flow!
 227    */
 228   else {
 229     printf("ERRROR: Received packet from different flow\nRETURN CODE: %d\n", DIFF_FLOW);
 230     PrintTcpPacket(p);
 231     Quit(DIFF_FLOW) ;
 232   }
 233
 234   if (session.debug == SESSION_DEBUG_HIGH) {
 235     printf("Out ProcessBadPacket...\n");
 236   }
 237 }
 238
 239 void busy_wait (double wait)
 240 {
 241   double now = GetTime();
 242   double x = now ;
 243   while ((x - now) < wait) {
 244     x = GetTime();
 245   }
 246 }