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         OSX support and EOF support by Pete Baker (peteb4ker@gmail.com), 2011
   8
   9         This program is free software; you can redistribute it and/or
  10         modify it under the terms of the GNU General Public License
  11         as published by the Free Software Foundation; either version 2
  12         of the License, or (at your option) any later version.
  13
  14         This program is distributed in the hope that it will be useful,
  15         but WITHOUT ANY WARRANTY; without even the implied warranty of
  16         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17         GNU General Public License for more details.
  18
  19         You should have received a copy of the GNU General Public License
  20         along with this program; if not, write to the Free Software Foundation
  21         Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  22         http://www.gnu.org/copyleft/gpl.html
  23
  24         07/09/1999 - Started writing.
  25         21Nov1999  - Cook: added command line support and extra error checking
  26         27Nov1999  - Cook: added select, timer & changed output look
  27         24Jun2011 - Baker: Added OSX support. Added EOF character support
  28 */
  29
  30 #define VERSION "0.0.4"
  31
  32 #include <stdio.h>
  33 #include <string.h>
  34 #include <fcntl.h>
  35 #include <termios.h>
  36 #include <unistd.h>
  37 #include <stdlib.h>
  38 #include <time.h>
  39 #include <sys/time.h>
  40 #include <errno.h>
  41
  42 #include "disp_basic.h"
  43 #include "tcp.h"
  44
  45 char * speed_str[] = { "300", "1200", "2400", "4800", "9600", "19200", "38400",
  46                 "57600", "115200", "230400", NULL };
  47 speed_t speed_num[] = { B300, B1200, B2400, B4800, B9600, B19200, B38400,
  48                 B57600, B115200, B230400, B0 };
  49
  50 int openport(const char *device, speed_t baud, int setup)
  51 {
  52         int filedes;
  53         struct termios serparams;
  54
  55         if ((filedes=open(device, O_RDWR | O_NONBLOCK))==-1) {
  56                 /* Can't open device */
  57                 fprintf(stderr,"%s: ",device);
  58                 perror(device);
  59                 exit(1);
  60         }
  61
  62         if (setup) {
  63                 bzero(&serparams, sizeof(serparams));
  64
  65                 cfsetspeed(&serparams, baud);
  66                 serparams.c_cflag |= CLOCAL | CS8 | CREAD;
  67
  68                 if (tcflush(filedes, TCIFLUSH)) {
  69                         fprintf(stderr,"%s: ",device);
  70                         perror("tcflush");
  71                         exit(1);
  72                 }
  73                 if (tcsetattr(filedes, TCSANOW, &serparams)) {
  74                         fprintf(stderr,"%s: ",device);
  75                         perror("tcsetattr");
  76                         exit(1);
  77                 }
  78         }
  79
  80         return filedes;
  81 }
  82
  83 int closeport(int filedes)
  84 {
  85         /* Should remove any locks at this point */
  86         return close(filedes);
  87 }
  88
  89 /*
  90    this returns the string for the character passed to it
  91    It could be expanded in the future to maybe to string recognitions?
  92 */
  93 char *chardecide(unsigned char c, int alpha, char *format) {
  94         static char result[256];
  95
  96         /* everyone should take up 5 characters */
  97         if (alpha) {
  98            if ((c < 32) | (c > 126)) {
  99                 switch (c) {
 100                         case 10:
 101                                 sprintf(result,"<LF>");
 102                                 break;
 103                         case 13:
 104                                 sprintf(result,"<CR>");
 105                                 break;
 106                         case 27:
 107                                 sprintf(result,"<ESC>");
 108                                 break;
 109                         default:
 110                                 snprintf(result,256,"<%02hX>",c);
 111                                 break;
 112                 }
 113            } else {
 114                 snprintf(result,256,"%c",c);
 115            }
 116         } else {
 117            snprintf(result,256,format,c);
 118         }
 119         return result;
 120 }
 121
 122 void outputchar(unsigned char c, int port, int alpha,
 123                 long usec_threshold, long usec_waited, char *name1, char *name2, char *format)
 124 {
 125         char *todisplay;
 126
 127         todisplay=chardecide(c,alpha,format);
 128         disp_outputstr(port, todisplay, usec_threshold, usec_waited, name1, name2);
 129 }
 130
 131 void mainloop(int port1, int port2, int silent, int alpha, int quit_on_eof, long usec_threshold, char *name1, char *name2, char *format)
 132 {
 133         unsigned char c1, c2;
 134         int rc;
 135         fd_set rfds;
 136         fd_set efds;
 137         int biggestfd=0;
 138         int fdret;
 139         struct timeval before;
 140         struct timeval after;
 141         long timediff;
 142         int quit=0;
 143
 144         /* need the largest fd for the select call */
 145         biggestfd=port1 > port2 ? port1 : port2;
 146         biggestfd++;
 147
 148         while (!quit) {
 149                 /* reset the select set */
 150                 FD_ZERO(&rfds);
 151                 FD_ZERO(&efds);
 152                 FD_SET(port1,&rfds);
 153                 FD_SET(port1,&efds);
 154                 FD_SET(port2,&rfds);
 155                 FD_SET(port2,&efds);
 156
 157                 if (gettimeofday(&before,NULL)) {
 158                         perror("gettimeofday");
 159                         exit(1);
 160                 }
 161                 if ((fdret=select(biggestfd, &rfds, NULL, &efds, NULL))<0) {
 162                         perror("select");
 163                         exit(1);
 164                 }
 165                 if (gettimeofday(&after,NULL)) {
 166                         perror("gettimeofday");
 167                         exit(1);
 168                 }
 169
 170                 /* get seconds difference */
 171                 timediff=after.tv_sec-before.tv_sec;
 172                 /* convert to micro seconds */
 173                 timediff*=USEC;
 174                 /* add difference in usecs */
 175                 timediff+=after.tv_usec-before.tv_usec;
 176
 177                 if (FD_ISSET(port1, &rfds)) {
 178                         for (rc=read(port1, &c1, 1);
 179                              rc>0; rc=read(port1, &c1, 1) ) {
 180                                 outputchar(c1,1,alpha,usec_threshold,timediff,name1,name2,format);
 181                                 timediff=0;
 182                                 if (!silent) write(port2,&c1,1);
 183                         }
 184                         if (rc==0 && quit_on_eof==1) {
 185                                 /* EOF? */
 186                                 quit=1;
 187                         }
 188                         if (rc<0 && errno!=EAGAIN) {
 189                                 perror("read(port1)");
 190                                 exit(1);
 191                         }
 192                 }
 193
 194                 if (FD_ISSET(port2, &rfds)) {
 195                         for (rc=read(port2, &c2, 1);
 196                              rc>0; rc=read(port2, &c2, 1) ) {
 197                                 outputchar(c2,2,alpha,usec_threshold,timediff,name1,name2,format);
 198                                 timediff=0;
 199                                 if (!silent) write(port1,&c2,1);
 200                         }
 201                         if (rc==0 && quit_on_eof==1) {
 202                                 /* EOF? */
 203                                 quit=1;
 204                         }
 205                         if (rc<0 && errno!=EAGAIN) {
 206                                 perror("read(port2)");
 207                                 exit(1);
 208                         }
 209                 }
 210
 211                 /* check for exceptions (sockets closed, broken, etc) */
 212                 if (FD_ISSET(port1, &efds)) {
 213                         /* I can't remember right now what to actually
 214                            check for on a fd exception, so we'll just quit */
 215                         fprintf(stderr,"\nException on port1\n");
 216                         quit=1;
 217                 }
 218                 if (FD_ISSET(port2, &efds)) {
 219                         /* I can't remember right now what to actually
 220                            check for on a fd exception, so we'll just quit */
 221                         fprintf(stderr,"\nException on port2\n");
 222                         quit=1;
 223                 }
 224         }
 225
 226         closeport(port2);
 227         closeport(port1);
 228 }
 229
 230 void usage()
 231 {
 232         fprintf(stderr,"sersniff v%s\n"
 233
 234 "Usage:\n"
 235 "sersniff [-h] [-i DEV | -l PORT] [-o DEV | -c HOST:PORT] [-b BAUD] [-w USEC]\n"
 236 "-h             This help\n"
 237 "-x             Show hex characters instead of alpha\n"
 238 "-f PRINTF_OPTS printf style options for printing hex characters\n"
 239 "               when '-x' switch is given (default \"<%%02hX>\")\n"
 240 "-i DEVICE      Port 1 device (defaults to /dev/ttyS0). Use host:port for\n"
 241 "                TCP.\n"
 242 "-1 PORT1_NAME  Port 1 name to be printed (defaults to 'Port1')\n"
 243 "-o DEVICE      Port 2 device (defaults to /dev/ttyS1). Use :port for TCP.\n"
 244 "-2 PORT2_NAME  Port 2 name to be printed (defaults to 'Port2')\n"
 245 "-b BAUD                Baud rate (Defaults to 19200)\n"
 246 "-n             No port configuration (do not set BAUD or change settings)\n"
 247 "-w USECS       How many microsecs to wait before reporting a delay\n"
 248 "                       (default is %d)\n"
 249 "-s             Silent - don't pass data from port1 <=> port2,\n"
 250 "                       just display what we see from them.\n"
 251 "-z             Don't quit when an EOF character is received.\n"
 252 ,VERSION,USEC);
 253         exit(1);
 254 }
 255
 256 int main(int argc, char *argv[])
 257 {
 258         int optret, speed;
 259         int port1, port2;
 260         char *dev1=NULL;
 261         char *dev2=NULL;
 262         char *name1=NULL;
 263         char *name2=NULL;
 264         int listenport=0;
 265         int connectport;
 266         char *connecthost=NULL, *tmpchr=NULL;
 267         int show_alpha=1;
 268         speed_t baud=B0;
 269         int silent=0;
 270         long usec_threshold=USEC;
 271         int setup_port=1;
 272         int quit_on_eof=1;
 273         char *format=NULL;
 274
 275         while ((optret=getopt(argc,argv,"hxsnzi:l:o:c:b:w:1:2:f:"))!=EOF) {
 276                 switch (optret) {
 277                 case '?': case 'h': case ':':
 278                         usage();
 279                 case 's':
 280                         silent=1;
 281                         break;
 282                 case 'w':
 283                         usec_threshold=atoi(optarg);
 284                         break;
 285                 case 'i':
 286                         if ((tmpchr=strchr(optarg, ':'))!=NULL &&
 287                             (strchr(optarg, '/')==NULL)) {
 288                                 *tmpchr='\0';
 289                                 listenport=atoi(++tmpchr);
 290                         } else {
 291                                 dev1=strdup(optarg);
 292                         }
 293                         break;
 294                 case 'o':
 295                         if ((tmpchr=strchr(optarg, ':'))!=NULL &&
 296                             (strchr(optarg, '/')==NULL)) {
 297                                 *tmpchr='\0';
 298                                 connectport=atoi(++tmpchr);
 299                                 connecthost=strdup(optarg);
 300                         } else {
 301                                 dev2=strdup(optarg);
 302                         }
 303                         break;
 304                 case 'x':
 305                         show_alpha=0;
 306                         break;
 307                 case 'b':
 308                         for (speed=0;
 309                              speed_str[speed];
 310                              speed++) {
 311                                 if (strstr(optarg,speed_str[speed])==optarg) {
 312                                         baud=speed_num[speed];
 313                                         break;
 314                                 }
 315                         }
 316                         if (baud==B0) {
 317                                 fprintf(stderr,"Unsupported Baud: '%s'\n",
 318                                         optarg);
 319                                 exit(1);
 320                         }
 321                         break;
 322                 case 'n':
 323                         setup_port=0;
 324                         break;
 325                 case '1':
 326                         name1=strdup(optarg);
 327                         break;
 328                 case '2':
 329                         name2=strdup(optarg);
 330                         break;
 331                 case 'f':
 332                         format=strdup(optarg);
 333                         break;
 334                 case 'z':
 335                         quit_on_eof=0;
 336                         break;
 337                 }
 338         }
 339
 340         /* Default settings */
 341         if (!dev1 && !listenport) dev1=strdup("/dev/ttyS0");
 342         if (!name1 && !listenport) name1=strdup("Port1");
 343         if (!dev2 && !connecthost) dev2=strdup("/dev/ttyS1");
 344         if (!name2 && !connecthost) name2=strdup("Port2");
 345         if (baud==B0) baud=B19200;
 346         if (!format) format=strdup("0x%02hX");
 347
 348         disp_init();
 349         if (dev1) {
 350                 port1=openport(dev1, baud, setup_port);
 351         } else {
 352                 disp_outputstatus("Waiting for connection to TCP port.");
 353                 port1=listensock(listenport);
 354         }
 355
 356         if (dev2) {
 357                 port2=openport(dev2, baud, setup_port);
 358         } else {
 359                 disp_outputstatus("Connecting to TCP port.");
 360                 port2=opensock(connecthost, connectport);
 361         }
 362
 363         if (port1 < 0 || port2 < 0) {
 364                 fprintf(stderr,"Argh.  An open failed!\n");
 365                 exit(1);
 366         }
 367
 368         mainloop(port1, port2, silent, show_alpha, quit_on_eof, usec_threshold, name1, name2, format);
 369
 370         /* Clean up */
 371         if (dev1) free(dev1);
 372         if (dev2) free(dev2);
 373         if (connecthost) free(connecthost);
 374         disp_close();
 375
 376         return 0;
 377 }