sersniff.c

   1 /*
   2         sersniff.c - A program to tunnel between 2 serial ports and
   3         sniff the data that passes between them. Designed to aid
   4         working out the protocol between a Nokia 9000i and NServer.
   5         Written by Jonathan McDowell for Project Purple, 1999
   6         Extra stuff by Cornelius Cook (cook@cpoint.net), 1999
   7
   8         This program is free software; you can redistribute it and/or
   9         modify it under the terms of the GNU General Public License
  10         as published by the Free Software Foundation; either version 2
  11         of the License, or (at your option) any later version.
  12
  13         This program is distributed in the hope that it will be useful,
  14         but WITHOUT ANY WARRANTY; without even the implied warranty of
  15         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16         GNU General Public License for more details.
  17
  18         You should have received a copy of the GNU General Public License
  19         along with this program; if not, write to the Free Software Foundation
  20         Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21         http://www.gnu.org/copyleft/gpl.html
  22
  23         07/09/1999 - Started writing.
  24         21Nov1999  - Cook: added command line support and extra error checking
  25         27Nov1999  - Cook: added select, timer & changed output look
  26 */
  27
  28 #define VERSION "0.0.4"
  29
  30 #include <stdio.h>
  31 #include <string.h>
  32 #include <fcntl.h>
  33 #include <termios.h>
  34 #include <unistd.h>
  35 #include <stdlib.h>
  36 #include <time.h>
  37 #include <sys/time.h>
  38 #include <errno.h>
  39
  40 #include "disp_basic.h"
  41 #include "tcp.h"
  42
  43 char * speed_str[] = { "300", "1200", "2400", "4800", "9600", "19200", "38400",
  44                 "57600", "115200", "230400", NULL };
  45 speed_t speed_num[] = { B300, B1200, B2400, B4800, B9600, B19200, B38400,
  46                 B57600, B115200, B230400, B0 };
  47
  48 int openport(const char *device, speed_t baud, int setup)
  49 {
  50         int filedes;
  51         struct termios serparams;
  52
  53         if ((filedes=open(device, O_RDWR | O_NONBLOCK))==-1) {
  54                 /* Can't open device */
  55                 fprintf(stderr,"%s: ",device);
  56                 perror(device);
  57                 exit(1);
  58         }
  59
  60         if (setup) {
  61                 bzero(&serparams, sizeof(serparams));
  62
  63                 serparams.c_cflag=baud | CLOCAL | CS8 | CREAD;
  64
  65                 if (tcflush(filedes, TCIFLUSH)) {
  66                         fprintf(stderr,"%s: ",device);
  67                         perror("tcflush");
  68                         exit(1);
  69                 }
  70                 if (tcsetattr(filedes, TCSANOW, &serparams)) {
  71                         fprintf(stderr,"%s: ",device);
  72                         perror("tcsetattr");
  73                         exit(1);
  74                 }
  75         }
  76
  77         return filedes;
  78 }
  79
  80 int closeport(int filedes)
  81 {
  82         /* Should remove any locks at this point */
  83         return close(filedes);
  84 }
  85
  86 /*
  87    this returns the string for the character passed to it
  88    It could be expanded in the future to maybe to string recognitions?
  89 */
  90 char *chardecide(unsigned char c, int alpha, char *format) {
  91         static char result[256];
  92
  93         /* everyone should take up 5 characters */
  94         if (alpha) {
  95            if ((c < 32) | (c > 126)) {
  96                 switch (c) {
  97                         case 10:
  98                                 sprintf(result,"<LF>");
  99                                 break;
 100                         case 13:
 101                                 sprintf(result,"<CR>");
 102                                 break;
 103                         case 27:
 104                                 sprintf(result,"<ESC>");
 105                                 break;
 106                         default:
 107                                 snprintf(result,256,"<%02hX>",c);
 108                                 break;
 109                 }
 110            } else {
 111                 snprintf(result,256,"%c",c);
 112            }
 113         } else {
 114            snprintf(result,256,format,c);
 115         }
 116         return result;
 117 }
 118
 119 void outputchar(unsigned char c, int port, int alpha,
 120                 long usec_threshold, long usec_waited, char *name1, char *name2, char *format)
 121 {
 122         char *todisplay;
 123
 124         todisplay=chardecide(c,alpha,format);
 125         disp_outputstr(port, todisplay, usec_threshold, usec_waited, name1, name2);
 126 }
 127
 128 void mainloop(int port1, int port2, int silent, int alpha, long usec_threshold, char *name1, char *name2, char *format)
 129 {
 130         unsigned char c1, c2;
 131         int last;
 132         int rc;
 133         fd_set rfds;
 134         fd_set efds;
 135         int biggestfd=0;
 136         int fdret;
 137         struct timeval before;
 138         struct timeval after;
 139         long timediff;
 140         int quit=0;
 141
 142         /* need the largest fd for the select call */
 143         biggestfd=port1 > port2 ? port1 : port2;
 144         biggestfd++;
 145         last=0;
 146
 147         while (!quit) {
 148                 /* reset the select set */
 149                 FD_ZERO(&rfds);
 150                 FD_ZERO(&efds);
 151                 FD_SET(port1,&rfds);
 152                 FD_SET(port1,&efds);
 153                 FD_SET(port2,&rfds);
 154                 FD_SET(port2,&efds);
 155
 156                 if (gettimeofday(&before,NULL)) {
 157                         perror("gettimeofday");
 158                         exit(1);
 159                 }
 160                 if ((fdret=select(biggestfd, &rfds, NULL, &efds, NULL))<0) {
 161                         perror("select");
 162                         exit(1);
 163                 }
 164                 if (gettimeofday(&after,NULL)) {
 165                         perror("gettimeofday");
 166                         exit(1);
 167                 }
 168
 169                 /* get seconds difference */
 170                 timediff=after.tv_sec-before.tv_sec;
 171                 /* convert to micro seconds */
 172                 timediff*=USEC;
 173                 /* add difference in usecs */
 174                 timediff+=after.tv_usec-before.tv_usec;
 175
 176                 if (FD_ISSET(port1, &rfds)) {
 177                         for (rc=read(port1, &c1, 1);
 178                              rc>0; rc=read(port1, &c1, 1) ) {
 179                                 outputchar(c1,1,alpha,usec_threshold,timediff,name1,name2,format);
 180                                 timediff=0;
 181                                 if (!silent) write(port2,&c1,1);
 182                         }
 183                         if (rc==0) {
 184                                 /* EOF? */
 185                                 quit=1;
 186                         }
 187                         if (rc<0 && errno!=EAGAIN) {
 188                                 perror("read(port1)");
 189                                 exit(1);
 190                         }
 191                 }
 192
 193                 if (FD_ISSET(port2, &rfds)) {
 194                         for (rc=read(port2, &c2, 1);
 195                              rc>0; rc=read(port2, &c2, 1) ) {
 196                                 outputchar(c2,2,alpha,usec_threshold,timediff,name1,name2,format);
 197                                 timediff=0;
 198                                 if (!silent) write(port1,&c2,1);
 199                         }
 200                         if (rc==0) {
 201                                 /* EOF? */
 202                                 quit=1;
 203                         }
 204                         if (rc<0 && errno!=EAGAIN) {
 205                                 perror("read(port2)");
 206                                 exit(1);
 207                         }
 208                 }
 209
 210                 /* check for exceptions (sockets closed, broken, etc) */
 211                 if (FD_ISSET(port1, &efds)) {
 212                         /* I can't remember right now what to actually
 213                            check for on a fd exception, so we'll just quit */
 214                         fprintf(stderr,"\nException on port1\n");
 215                         quit=1;
 216                 }
 217                 if (FD_ISSET(port2, &efds)) {
 218                         /* I can't remember right now what to actually
 219                            check for on a fd exception, so we'll just quit */
 220                         fprintf(stderr,"\nException on port2\n");
 221                         quit=1;
 222                 }
 223         }
 224
 225         closeport(port2);
 226         closeport(port1);
 227 }
 228
 229 void usage()
 230 {
 231         fprintf(stderr,"sersniff v%s\n"
 232
 233 "Usage:\n"
 234 "sersniff [-h] [-i DEV | -l PORT] [-o DEV | -c HOST:PORT] [-b BAUD] [-w USEC]\n"
 235 "-h             This help\n"
 236 "-x             Show hex characters instead of alpha\n"
 237 "-f PRINTF_OPTS printf style options for printing hex characters\n"
 238 "               when '-x' switch is given (default \"<%%02hX>\")\n"
 239 "-i DEVICE      Port 1 device (defaults to /dev/ttyS0). Use host:port for\n"
 240 "                TCP.\n"
 241 "-1 PORT1_NAME  Port 1 name to be printed (defaults to 'Port1')\n"
 242 "-o DEVICE      Port 2 device (defaults to /dev/ttyS1). Use :port for TCP.\n"
 243 "-2 PORT2_NAME  Port 2 name to be printed (defaults to 'Port2')\n"
 244 "-b BAUD                Baud rate (Defaults to 19200)\n"
 245 "-n             No port configuration (do not set BAUD or change settings)\n"
 246 "-w USECS       How many microsecs to wait before reporting a delay\n"
 247 "                       (default is %d)\n"
 248 "-s             Silent - don't pass data from port1 <=> port2,\n"
 249 "                       just display what we see from them.\n"
 250 ,VERSION,USEC);
 251         exit(1);
 252 }
 253
 254 int main(int argc, char *argv[])
 255 {
 256         int optret, speed;
 257         int port1, port2;
 258         char *dev1=NULL;
 259         char *dev2=NULL;
 260         char *name1=NULL;
 261         char *name2=NULL;
 262         int listenport=0;
 263         int connectport;
 264         char *connecthost=NULL, *tmpchr=NULL;
 265         int show_alpha=1;
 266         speed_t baud=B0;
 267         int silent=0;
 268         long usec_threshold=USEC;
 269         int setup_port=1;
 270         char *format=NULL;
 271
 272         while ((optret=getopt(argc,argv,"hxsni:l:o:c:b:w:1:2:f:"))!=EOF) {
 273                 switch (optret) {
 274                 case '?': case 'h': case ':':
 275                         usage();
 276                 case 's':
 277                         silent=1;
 278                         break;
 279                 case 'w':
 280                         usec_threshold=atoi(optarg);
 281                         break;
 282                 case 'i':
 283                         if ((tmpchr=strchr(optarg, ':'))!=NULL &&
 284                             (strchr(optarg, '/')==NULL)) {
 285                                 *tmpchr='\0';
 286                                 listenport=atoi(++tmpchr);
 287                         } else {
 288                                 dev1=strdup(optarg);
 289                         }
 290                         break;
 291                 case 'o':
 292                         if ((tmpchr=strchr(optarg, ':'))!=NULL &&
 293                             (strchr(optarg, '/')==NULL)) {
 294                                 *tmpchr='\0';
 295                                 connectport=atoi(++tmpchr);
 296                                 connecthost=strdup(optarg);
 297                         } else {
 298                                 dev2=strdup(optarg);
 299                         }
 300                         break;
 301                 case 'x':
 302                         show_alpha=0;
 303                         break;
 304                 case 'b':
 305                         for (speed=0;
 306                              speed_str[speed];
 307                              speed++) {
 308                                 if (strstr(optarg,speed_str[speed])==optarg) {
 309                                         baud=speed_num[speed];
 310                                         break;
 311                                 }
 312                         }
 313                         if (baud==B0) {
 314                                 fprintf(stderr,"Unsupported Baud: '%s'\n",
 315                                         optarg);
 316                                 exit(1);
 317                         }
 318                         break;
 319                 case 'n':
 320                         setup_port=0;
 321                         break;
 322                 case '1':
 323                         name1=strdup(optarg);
 324                         break;
 325                 case '2':
 326                         name2=strdup(optarg);
 327                         break;
 328                 case 'f':
 329                         format=strdup(optarg);
 330                         break;
 331                 }
 332         }
 333
 334         /* Default settings */
 335         if (!dev1 && !listenport) dev1=strdup("/dev/ttyS0");
 336         if (!name1 && !listenport) name1=strdup("Port1");
 337         if (!dev2 && !connecthost) dev2=strdup("/dev/ttyS1");
 338         if (!name2 && !connecthost) name2=strdup("Port2");
 339         if (baud==B0) baud=B19200;
 340         if (!format) format=strdup("0x%02hX");
 341
 342         disp_init();
 343         if (dev1) {
 344                 port1=openport(dev1, baud, setup_port);
 345         } else {
 346                 disp_outputstatus("Waiting for connection to TCP port.");
 347                 port1=listensock(listenport);
 348         }
 349
 350         if (dev2) {
 351                 port2=openport(dev2, baud, setup_port);
 352         } else {
 353                 disp_outputstatus("Connecting to TCP port.");
 354                 port2=opensock(connecthost, connectport);
 355         }
 356
 357         if (port1 < 0 || port2 < 0) {
 358                 fprintf(stderr,"Argh.  An open failed!\n");
 359                 exit(1);
 360         }
 361
 362         mainloop(port1, port2, silent, show_alpha, usec_threshold, name1, name2, format);
 363
 364         /* Clean up */
 365         if (dev1) free(dev1);
 366         if (dev2) free(dev2);
 367         if (connecthost) free(connecthost);
 368         disp_close();
 369
 370         return 0;
 371 }