isisd/isis_misc.c

/*
 * IS-IS Rout(e)ing protocol - isis_misc.h
 *                             Miscellanous routines
 *
 * Copyright (C) 2001,2002   Sampo Saaristo
 *                           Tampere University of Technology      
 *                           Institute of Communications Engineering
 *
 * This program is free software; you can redistribute it and/or modify it 
 * under the terms of the GNU General Public Licenseas 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 <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <ctype.h>
#include <zebra.h>
#include <net/ethernet.h>


#include "stream.h"
#include "vty.h"
#include "hash.h"
#include "if.h"

#include "isisd/dict.h"
#include "isisd/isis_constants.h"
#include "isisd/isis_common.h"
#include "isisd/isis_circuit.h"
#include "isisd/isisd.h"
#include "isisd/isis_misc.h"

#include "isisd/isis_tlv.h"
#include "isisd/isis_lsp.h"
#include "isisd/isis_constants.h"
#include "isisd/isis_adjacency.h"

/*
 * This converts the isonet to its printable format
 */
char * isonet_print (u_char *from, int len) {
  int i = 0;
  char *pos = isonet;

  if(!from)
    return "unknown";

  while (i < len) {
    if (i & 1) {
      sprintf ( pos, "%02x", *(from + i));
      pos += 2;
    } else {
      if (i == 0) { /* if the area addr is just one byte, eg. 47. */
        sprintf ( pos, "%02x", *(from + i));
        pos += 2;
      } else {
        sprintf ( pos, "%02x.", *(from + i));
        pos += 3;
      }
    }
    i++;
  }
  *(pos) = '\0';
  return isonet;
}

/*
 * Returns 0 on error, length of buff on ok
 * extract dot from the dotted str, and insert all the number in a buff 
 */
int
dotformat2buff (u_char *buff, u_char *dotted)
{
  int dotlen, len = 0;
  u_char *pos = dotted;
  u_char number[3];
  int nextdotpos = 2;

  number[2] = '\0';
  dotlen = strlen(dotted);
  if (dotlen > 50) {
    /* this can't be an iso net, its too long */
    return 0;
  }

  while ( (pos - dotted) < dotlen && len < 20 ) {
    if (*pos == '.') {
      /* we expect the . at 2, and than every 5 */
      if ((pos - dotted) != nextdotpos) {
        len = 0;
        break;
      }
      nextdotpos += 5;
      pos++;
      continue;
    }
    /* we must have at least two chars left here */
    if (dotlen - (pos - dotted) < 2) {
      len = 0;
      break;
    }

    if ((isxdigit((int)*pos)) && (isxdigit((int)*(pos+1)))){
      memcpy (number, pos ,2);
      pos+=2;
    } else {
      len = 0;
      break;
    }

    *(buff + len) = (char)strtol(number, NULL, 16);
    len++;
  }
  
  return len;
}
/*
 * conversion of XXXX.XXXX.XXXX to memory
 */
int
sysid2buff (u_char *buff, u_char *dotted)
 {
  int len = 0;
  u_char *pos = dotted;
  u_char number[3];

  number[2] = '\0';
  // surely not a sysid_string if not 14 length
  if (strlen(dotted) != 14) {
    return 0;
  }

  while ( len < ISIS_SYS_ID_LEN ) {
    if (*pos == '.') {
      /* the . is not positioned correctly */
      if (((pos - dotted) !=4) && ((pos - dotted) != 9)) { 
        len = 0;
        break;
      }
      pos++;
      continue;
    }
    if ((isxdigit((int)*pos)) && (isxdigit((int)*(pos+1)))){
      memcpy (number, pos ,2);
      pos+=2;
    } else {
      len = 0;
      break;
    }

    *(buff + len) = (char)strtol(number, NULL, 16);
    len++;
  }

  return len;

}

/*
 * converts the nlpids struct (filled by TLV #129)
 * into a string
 */

char *
nlpid2string (struct nlpids *nlpids) {
  char *pos = nlpidstring;
  int i;

  for (i=0;i<nlpids->count;i++) {
    switch (nlpids->nlpids[i]) {
    case NLPID_IP:
      pos += sprintf (pos, "IPv4");
      break;
    case NLPID_IPV6:
      pos += sprintf (pos, "IPv6");
      break;
    default:
      pos += sprintf (pos, "unknown");
      break;
    }
    if (nlpids->count-i>1)
      pos += sprintf (pos, ", ");
    
  }

  *(pos) = '\0';
  
  return nlpidstring;
}

/*
 *  supports the given af ?
 */
int 
speaks (struct nlpids *nlpids, int family)
{
  int i, speaks = 0;
  
  if (nlpids == (struct nlpids*)NULL)
    return speaks;
  for (i = 0;i < nlpids->count; i++) {
    if (family == AF_INET && nlpids->nlpids[i] == NLPID_IP)
      speaks = 1;
    if (family == AF_INET6 && nlpids->nlpids[i] == NLPID_IPV6)
      speaks = 1;
  }

  return speaks;
}


/*
 * Returns 0 on error, IS-IS Circuit Type on ok
 */
int 
string2circuit_t (u_char *str)
{
  
  if (!str)
    return 0;
  
  if (!strcmp(str,"level-1"))
    return IS_LEVEL_1;

  if (!strcmp(str,"level-2-only") || !strcmp(str,"level-2"))
    return IS_LEVEL_2;
  
  if (!strcmp(str,"level-1-2"))
    return IS_LEVEL_1_AND_2;

  return 0;
}

const char *
circuit_t2string (int circuit_t)
{
  switch (circuit_t) {
  case IS_LEVEL_1:
    return "L1";
  case IS_LEVEL_2:
    return "L2";
  case IS_LEVEL_1_AND_2:
    return "L1L2";
  default:
    return "??";
  }

  return NULL; /* not reached */
}

const char *
syst2string (int type)
{
  switch (type) {
  case ISIS_SYSTYPE_ES:
    return "ES";
  case ISIS_SYSTYPE_IS:
    return "IS";
  case ISIS_SYSTYPE_L1_IS:
    return "1";
  case ISIS_SYSTYPE_L2_IS:
    return "2";
  default:
    return "??";
  }

  return NULL; /* not reached */
}

/*
 * Print functions - we print to static vars
 */
char *
snpa_print (u_char *from)
{
  int i = 0;
  u_char *pos = snpa;

  if(!from)
    return "unknown";
  
  while (i < ETH_ALEN - 1) {
    if (i & 1) {
      sprintf ( pos, "%02x.", *(from + i));
      pos += 3;
    } else {
      sprintf ( pos, "%02x", *(from + i));
      pos += 2;

    }
    i++;
  }

  sprintf (pos, "%02x", *(from + (ISIS_SYS_ID_LEN - 1)));
  pos += 2;
  *(pos) = '\0';

  return snpa;
}

char *
sysid_print (u_char *from)
{
  int i = 0;
  char *pos = sysid;

  if(!from)
    return "unknown";

  while (i < ISIS_SYS_ID_LEN - 1) {
    if (i & 1) {
      sprintf ( pos, "%02x.", *(from + i));
      pos += 3;
    } else {
      sprintf ( pos, "%02x", *(from + i));
      pos += 2;
    
    } 
    i++;
  }

  sprintf (pos, "%02x", *(from + (ISIS_SYS_ID_LEN - 1)));
  pos += 2;
  *(pos) = '\0';
  
  return sysid;
}

char *
rawlspid_print (u_char *from)
{
  char *pos = lspid;
  if(!from)
    return "unknown";
  memcpy(pos, sysid_print(from), 15);
  pos += 14;
  sprintf (pos, ".%02x", LSP_PSEUDO_ID(from));
  pos += 3;
  sprintf (pos, "-%02x", LSP_FRAGMENT(from));
  pos += 3;

  *(pos) = '\0';

  return lspid;
}

char *
time2string (u_int32_t time) {
  char *pos = datestring; 
  u_int32_t rest;

  if (time==0)
    return "-";

  if(time/SECS_PER_YEAR)
    pos += sprintf (pos, "%uY",time/SECS_PER_YEAR);
  rest=time%SECS_PER_YEAR;    
  if(rest/SECS_PER_MONTH)
    pos += sprintf (pos, "%uM",rest/SECS_PER_MONTH);
  rest=rest%SECS_PER_MONTH;  
  if(rest/SECS_PER_WEEK)
    pos += sprintf (pos, "%uw",rest/SECS_PER_WEEK);
  rest=rest%SECS_PER_WEEK;    
  if(rest/SECS_PER_DAY)
    pos += sprintf (pos, "%ud",rest/SECS_PER_DAY);
  rest=rest%SECS_PER_DAY;    
  if(rest/SECS_PER_HOUR)
    pos += sprintf (pos, "%uh",rest/SECS_PER_HOUR);
  rest=rest%SECS_PER_HOUR;    
  if(rest/SECS_PER_MINUTE)
    pos += sprintf (pos, "%um",rest/SECS_PER_MINUTE);
  rest=rest%SECS_PER_MINUTE;    
  if(rest)
    pos += sprintf (pos, "%us",rest);   
 
  *(pos) = 0;

  return datestring;
}

/*
 * routine to decrement a timer by a random
 * number
 *
 * first argument is the timer and the second is
 * the jitter
 */
unsigned long 
isis_jitter (unsigned long timer, unsigned long jitter)
{
  int j,k;

  if (jitter>=100)
    return timer;

  if (timer == 1)
    return timer;
  /* 
   * randomizing just the percent value provides
   * no good random numbers - hence the spread
   * to RANDOM_SPREAD (100000), which is ok as
   * most IS-IS timers are no longer than 16 bit
   */

  j = 1 + (int) ((RANDOM_SPREAD * rand()) / (RAND_MAX + 1.0 )); 

  k = timer - (timer * (100 - jitter))/100;

  timer = timer - (k * j / RANDOM_SPREAD);

  return timer;
}

struct in_addr
newprefix2inaddr (u_char *prefix_start, u_char prefix_masklen) 
{
  memset(&new_prefix, 0, sizeof (new_prefix));
  memcpy(&new_prefix, prefix_start, (prefix_masklen & 0x3F) ? 
	 ((((prefix_masklen & 0x3F)-1)>>3)+1) : 0);
  return new_prefix;
}