extprog.c

/* $Id: extprog.c,v 1.11 2003/03/25 00:21:46 d3august Exp $
*/
/*  xtraceroute - graphically show traceroute information.
 *  Copyright (C) 1996-1998  Björn Augustsson 
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */


#include "xt.h"
#include <ctype.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>

traceroute_state_t traceroute_state;

extern GtkWidget *clist;    // from main.c

/**
 * get_from_extDNS collects data from the external program into a per-site
 * buffer. When the pipe runs out of data, it closes it.
 *
 * It is used as a callback.
 *
 * The fd argument is the same thing as site->extpipe[0].
 */

gint 
get_from_extDNS(site* site, int fd, GdkInputCondition cond)
{
  int count;
  char c;

  if(!(cond & GDK_INPUT_READ))
    {
      DPRINTF("Huh? Not read?\n");
      return FALSE;
    }
  
  count = read(fd, &c, 1);   //FIXME future performance opt, read more than a byte at a time.
  
  /* This can happen, it's a nonblocking pipe */
  if (count == -1)
    { 
      if(errno != EAGAIN)
	perror("read in get_from_extdns"); 

      if(site->extpipe_data[strlen(site->extpipe_data)-1] == '\n' )
	{
          /* Trigger the test to abort if we're resolving localhost. 
             Add that to here? */
          site->extpipe_active = FALSE;
	  return FALSE;
	}
      else
	return TRUE; 
    }
 
  if(count == 0)
    {
      DPRINTF("wow");
      return TRUE;
    }
 
  if(c == 0)
    {
      DPRINTF("wow2");
      return TRUE;
     }
 
  site->extpipe_data[site->extpipe_data_counter++] = c;
  
  if(c == '\n')
    {
      int i = 0;
      site->extpipe_data[site->extpipe_data_counter] = '\0';
      
      /* Parse the data. If the first word is "Nothing", abort now. */

      if(!strncmp(site->extpipe_data, "Nothing", strlen("Nothing")))
	goto escape;
      else if(!strncmp(site->extpipe_data, "Strange host version", 
		       strlen("Strange host version")))
        {
	  printf("Strange version of the \"host\" program found!\n"
		 "I can't use this, see the man page for details.\n");
	  exit(EXIT_FAILURE);
        }

      /*  Otherwise skip it. */
      while(!is_whitespace(site->extpipe_data[i]))
	i++;
      /* Now skip all whitespace after that. */
      while(is_whitespace(site->extpipe_data[i]))
	i++;
      
      if(!strncmp(&site->extpipe_data[i], "LOC", 3))
	{
	  float tmplat, tmplon;
	  i += 3;
	  
	  /* Actually do something with the data. */
	  
	  tmplat = locStrToNum(&site->extpipe_data[i], LATITUDE);
	  if(tmplat < -900)
	    {
	      /* It was an illegal LOC string! */
	      goto escape;
	    }
	  site->lat = tmplat;

	  while(toupper(site->extpipe_data[i]) != 'N' && 
		toupper(site->extpipe_data[i]) != 'S')
	    {
	      i++;
	    }
	  i++;
	  
	  tmplon = locStrToNum(&site->extpipe_data[i], LONGITUDE);
	  if(tmplon < -900)
	    {
	      /* It was an illegal LOC string! */
	      goto escape;
	    }
	  site->lon = tmplon;

	  site->accuracy = ACC_RFC_1876;
	  DPRINTF("Whee! LOC data for: %s\n", site->name);
	  strcpy(site->info, "No further info.");
	  
escape:
	  gdk_input_remove(site->extpipe_tag); 
	  close(fd);
	  site->extpipe[0]           = -1;
	  site->extpipe_tag          = 0;
	  site->extpipe_data_counter = 0;
	  site->extpipe_active       = FALSE;
	  
	  if( !(cond & SYNCH_RESOLV) )
	    {
	      arrangeUnknownSites();
	      makeearth();
	    }
	  return FALSE;
	}
      else if(i==1)
	{
	  /* Not supposed to happen. It's probably a bug if it does. */
	  DPRINTF("Hmmm. An empty line...\n");
          DPRINTF("\tData:\"%s\"\n", site->extpipe_data);
	}
      else   /* Strange data */
	{
	  printf("Didn't get expected in the string from host helper!\n");
	  printf("This is what I got: \"%s\"\n", site->extpipe_data);
	}
      site->extpipe_data_counter = 0;
    }
  return TRUE;
} 


/**
 * callExternalDNS() calls an external program (at this point "host") and
 * sets up a per-site pipe to its' output.
 */

void callExternalDNS(site* site)
{
    if(pipe(site->extpipe) == -1)
    {
      perror("pipe"); 
      exit(EXIT_FAILURE);
    }

  if(fcntl(site->extpipe[0], F_SETFL, O_NONBLOCK) != 0)
    {
      perror("O_NONBLOCKifying pipe");
      exit(EXIT_FAILURE);
    }

  /* Make a distinction here host/localhost here? */

  spinner_ref("host");

  site->extpipe_pid = fork();

  switch (site->extpipe_pid)
    {
    case -1:
      /* Fork failed! */
      perror("fork");
      exit(EXIT_FAILURE);
      break;
    case 0:      
      /* We're going to be the exernal program! */
      
      close(site->extpipe[0]);    /* close read end of pipe               */
      //      close(STDERR_FILENO);       /* close stderr. I'm not interested.    */
      dup2(site->extpipe[1], STDOUT_FILENO); /* make 1 same as write-to end of pipe  */
      dup2(site->extpipe[1], STDERR_FILENO); /* make 2 same as write-to end of pipe  */
      close(site->extpipe[1]);    /* close excess fildes                  */

      execlp(DATADIR "/xtraceroute-resolve-location.sh", 
             "xtraceroute-resolve-location.sh", site->name, NULL); 
      perror("exec");       /* still around?  exec failed           */
      _exit(EXIT_FAILURE);  /* no flush                             */ 
      break;
    default:
      /* We're the parent */
      site->extpipe_active = TRUE;
      site->extpipe_tag = gdk_input_add(site->extpipe[0], GDK_INPUT_READ,
					(GdkInputFunction)get_from_extDNS, site);
    }
}


/*********************************************************************/


/**
 * Only called from get_from_traceroute() when it gets a whole line.
 */

static void 
parse_row_from_traceroute(char *input)
{
    int i;
    int no = 1; /* no SEGV if sscanf fails */
    int last;
    char *clistrow[3];
    char ipbuf[INET6_ADDRSTRLEN];

    /* This is a SGI compatibility thing; On SGI "traceroute" prints
       the first line "traceroute to test.com (0.0.0.0), 40 hops max,
       40 byte packets" to stdout instad of stderr (which most other
       machines does). FWIW, I actually think SGI's behavior is saner
       (stderr is for errors!), but... */
    /* On the other hand, SGI-traceroute prints errors as well to
       stdout... Oh well... */
  
    if (!strncasecmp("traceroute",input, 10)) {
	DPRINTF("Got traceroute header!\n");

	if(isin("unknown host", input))
	{
	    char tmp[200];
	    DPRINTF("unknown host!\n");
	    gdk_input_remove(traceroute_state.tag);
	    close(traceroute_state.fd[0]);
	    traceroute_state.fd[0] = -1;
	    strcpy(tmp, _("xtraceroute: unknown host "));
	    strcat(tmp, user_settings->current_target);
	    tell_user(tmp);
	    traceroute_state.scanning = 0;
	}
	return;

    } else if (strlen(input)< 10) {
	/* All we got was a couple of spaces, from a "XXX * * *"-row, that's
	   had the stars stripped off */

	sscanf(input, "%d", &no);
	no--;
	strcpy(sites[no].name, "No response");
	//strcpy(sites[no].ip  , "No response");
	memset(&sites[no].ip, 0, sizeof(sites[no].ip));
	strcpy(sites[no].info, "There were no response from this machine.");
	sites[no].lat = sites[no-1].lat; // FIXME:
	sites[no].lon = sites[no-1].lon; //potential trouble here if no == 0.
	sites[no].time = 0;
	sites[no].accuracy = ACC_NONE;
	sites[no].draw = 1;

    } else {
	 /* All is well, do the normal stuff. */
	i = sscanf(input,"%d",&no);
      
	/* Skip past the first number. */
	while(!isspace(input[i]))
	    i++;
	no--;
	sscanf(input+i, "%s (%[0-9a-fA-F.:]) %d", sites[no].name, ipbuf, &sites[no].time);
      
	resolve_by_id(no, ipbuf);
	makeearth();       /* FIXME maybe this should'nt be here. */
    }

    clistrow[0] = (char *)malloc(10);
    //clistrow[1] = (char *)malloc(IP_STR_LEN);
    clistrow[2] = (char *)malloc(IP_STR_LEN);
  
    sprintf(clistrow[0], "%d", no);
    clistrow[1] = strdup(sites[no].name);
    addr2str(&sites[no].ip, clistrow[2], IP_STR_LEN);
  
    /* Add an entry to the list */
    last = gtk_clist_append(GTK_CLIST(clist), clistrow);
  
    /* Free the clistrow here */
    free(clistrow[0]);
    free(clistrow[1]);
    free(clistrow[2]);
    /* The above SHOULD be done! But there's an error here somewhere.
       Doing that causes malloc in glibc-linux to dump sometimes.
       Investigating... This just has to be a glibc bug... Efence
       finds nothing... (This comment kept in case it shows up
       again.) */
  
    /* Scroll the clist so the new entry is visible */
    gtk_clist_moveto(GTK_CLIST(clist), last, 1, 1.0, 0.5);
  
    if(no >= MAX_SITES-1)
    {
	/*
	  printf("Too many hops! Change the MAX_SITES value in xt.h,\n");
	  printf("recompile, and mail August and tell him about it!\n");
	*/
	close(traceroute_state.fd[0]);
	traceroute_state.fd[0]    = -1;
	traceroute_state.scanning = 0;
	gdk_input_remove(traceroute_state.tag);
	spinner_unref("traceroute");
	makeearth();
    }
    return;
}

/**
 * get_from_traceroute collects data from the external traceroute 
 * program into a buffer. When it has a whole line, it calls
 * parse_row_from_traceroute().
 *
 * When the pipe runs out of data, it gets closed.
 *
 * It is used as a callback.
 */

gint 
get_from_traceroute(char* nope, int fd, GdkInputCondition cond)
{
    //    DPRINTF(".");

    if(traceroute_state.scanning == 0)
    {
	/* FIX for API brokenness. This callback should unregister if
	   it returns false, as all other callbacks (in gtk at least)
	   do. */
	gdk_input_remove(traceroute_state.tag);

	return FALSE;
    }
    if(cond & GDK_INPUT_READ)
    {
	int count;
	char c;

	count = read(fd, &c, 1);   //FIXME future performance opt, read more than a byte at a time.
      
	if(c == -1)  printf("Hmmm.. -1 from read.\n");

	if(c == 0)  printf("Hmmm.. This shouldn't happen.\n");

	if(count == 0)          /* Other end of pipe closed. */
	{
	    close(traceroute_state.fd[0]); // Hmmm... what if this is stdin?
	    traceroute_state.fd[0] = -1;
	    traceroute_state.scanning = 0;
	    makeearth();
	    spinner_unref("traceroute");
	    gdk_input_remove(traceroute_state.tag); /* Fix for bad API. See above. */
	    return FALSE;
	}

	if(c == '*')
	    return TRUE;
      
	traceroute_state.row_so_far[traceroute_state.buffer_counter++] = c;
      
	if(c == '\n')
	{
	    traceroute_state.row_so_far[traceroute_state.buffer_counter] = '\0';
	    parse_row_from_traceroute(traceroute_state.row_so_far);
	    traceroute_state.buffer_counter = 0;
	}
    }
    return TRUE;
} 


/** 
 * Calls traceroute if the argument is 0, else reads debug input from stdin. 
 */
void 
calltrace(void)
{
    /* I don't know if there are several versions of traceroute out
     * there, but hopefully they can be configured to deliver what I
     * want with this.  Otherwise, this function must be hacked some
     * more.  */
  
    char tracepgm[]   = TRACEPGM;
  
    DPRINTF("calltrace\n");

    if(!strncmp(user_settings->current_target, "-", strlen("-"))) {
	traceroute_state.fd[0] = STDIN_FILENO;
	traceroute_state.scanning = 1;
	spinner_ref("traceroute");
	traceroute_state.tag = gdk_input_add(traceroute_state.fd[0], GDK_INPUT_READ,
					     (GdkInputFunction)get_from_traceroute, NULL);
	return;
    }
  
    if (pipe(traceroute_state.fd) == -1) {
	perror("traceroute pipe");
	exit(EXIT_FAILURE);
    }
  
    traceroute_state.pid = fork();
  
    switch (traceroute_state.pid)
    {
    case -1:
	/* Fork failed! */
	perror("fork");
	exit(EXIT_FAILURE);
	break;
    case 0:      
	/* We're going to be the exernal program! */
      
	close(traceroute_state.fd[0]);    /* close read end of pipe */
	dup2(traceroute_state.fd[1], STDOUT_FILENO); /* make 1 same as write-to end of pipe */
	dup2(traceroute_state.fd[1], STDERR_FILENO); /* make 2 same as write-to end of pipe */
	close(traceroute_state.fd[1]);    /* close excess fildes */

	/* FIXME I'd _like_ to use the MAX_SITES define instead of
	   "40" here, but that doesn't work since it's in a string.
	   Suggestions? */
	execlp(tracepgm, "traceroute",
	       "-q", "2",  /* Two queries (default is 3.) */
	       "-w", "20", /* Time before timing out (default is 5) */
	       "-m", "40", /* Max hops, default is 30, we need more. */
	       user_settings->current_target, NULL);
	perror("exec");       /* still around?  exec failed */
	_exit(EXIT_FAILURE);  /* no flush */
	break;
    default:
	/* We're the parent */
	traceroute_state.scanning = 1;
	spinner_ref("traceroute");
	traceroute_state.tag = gdk_input_add(traceroute_state.fd[0], GDK_INPUT_READ,
					     (GdkInputFunction)get_from_traceroute, NULL);
    }
}