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   1 /* route.c              Route file reader
   2  *
   3  * $Id: route.c,v 1.3 1995/03/19 17:21:06 bdale Exp $
   4  *
   5  * Copyright 1991, Michael Westerhof, Sun Microsystems, Inc.
   6  * This software may be freely used, distributed, or modified, providing
   7  * this header is not removed.
   8  *
   9  */
  10
  11 #include <stdio.h>
  12 #include <sys/types.h>
  13 #include <sys/socket.h>
  14 #include <netdb.h>
  15 #include <memory.h>
  16 #include <fcntl.h>
  17 #include <string.h>
  18 #include <ctype.h>
  19 #include <netinet/in.h>
  20 #include <arpa/inet.h>
  21 #include <syslog.h>
  22 #include <stdlib.h>
  23
  24 #include "ipip.h"
  25
  26 static void rerr();             /* General error printer */
  27 static void init_route();
  28 static void r_route();
  29 static void print_routes();
  30 static void sort_routes();
  31
  32 static int rlineno;
  33 static int rerrflag;
  34 int rts_top;
  35 struct ipip_route rts[MAX_ROUTES];
  36
  37 /*
  38  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  39  * open and read the route file
  40  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  41  */
  42 int
  43 read_routes(f)
  44 char *f;
  45 {
  46         FILE *cf;
  47         char buf[256], *p;
  48
  49         init_route();
  50
  51 /* Open the route file */
  52         if((cf = fopen(f,"r"))==NULL){
  53                 (void)fprintf(stderr,"%sRoute file %s not found or could not be opened\n",progname,f);
  54                 return -1;
  55         }
  56
  57         while(fgets(buf, 255, cf)!=NULL){
  58                 rlineno++;
  59                 if((p = strtok(buf, " \t\n\r"))==NULL)continue;
  60                 if(*p=='#' || *p==';')continue;
  61
  62                 if(strcmp(p,"route")==0)r_route();
  63 /*              else if(strcmp(p,"whatever")==0)r_dowhatever(); */
  64                 else rerr("Unrecognized command: %s",p);
  65         }
  66
  67         if(rts_top==0)rerr("No routes defined","");
  68
  69         if(debugd)print_routes();
  70
  71         sort_routes();
  72
  73         if(debugd)print_routes();
  74
  75         return rerrflag;
  76 }
  77 /*
  78  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  79  * Initialize defaults and null route entries
  80  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  81  */
  82 static void
  83 init_route()
  84 {
  85         int i;
  86
  87         for(i=0;i<MAX_ROUTES;i++){
  88                 rts[i].ipaddr = 0;
  89                 rts[i].mask = 0xffffffff;
  90                 rts[i].destif = NULL;
  91                 rts[i].destaddr = 0;
  92                 rts[i].destport = 0;
  93                 rts[i].hits = 0;
  94         }
  95         rts_top = 0;
  96
  97         rlineno = 0;
  98         rerrflag = 0;
  99 }
 100
 101 /*
 102  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 103  * Print out the route table (DEBUG)
 104  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 105  */
 106 static void
 107 print_routes()
 108 {
 109         int i, port, type;
 110         unsigned char *p, *q;
 111         char *id;
 112         unsigned int m;
 113
 114         if(rerrflag==0)(void)syslog(LOG_DEBUG,"%d routes:", rts_top);
 115         else (void)syslog(LOG_DEBUG,"%d routes (there are errors):", rts_top);
 116         for(i=0;i<rts_top;i++){
 117                 p = (unsigned char *)&rts[i].ipaddr;
 118                 q = (unsigned char *)&rts[i].destaddr;
 119                 if(rts[i].destif != NULL){
 120                         id = rts[i].destif->id;
 121                         type = rts[i].destif->type;
 122                 } else {
 123                         id = "unknown";
 124                         type = IF_TYPE_NONE;
 125                 }
 126                 port = ntohs(rts[i].destport);
 127                 m = ntohl(rts[i].mask);
 128
 129                 if((type == IF_TYPE_SLIP)||
 130                    (type == IF_TYPE_TUN)){
 131                         (void)syslog(LOG_DEBUG,"ip %d.%d.%d.%d mask 0x%08x interface %s\n",
 132                                 p[0],p[1],p[2],p[3],m,id);
 133                 } else if(type == IF_TYPE_IPIP){
 134                         (void)syslog(LOG_DEBUG,"ip %d.%d.%d.%d mask 0x%08x interface %s ip %d.%d.%d.%d\n",
 135                                 p[0],p[1],p[2],p[3],m,id,
 136                                 q[0],q[1],q[2],q[3]);
 137                 } else {
 138                         (void)syslog(LOG_DEBUG,"ip %d.%d.%d.%d mask 0x%08x interface %s ip %d.%d.%d.%d port %d\n",
 139                                 p[0],p[1],p[2],p[3],m,id,
 140                                 q[0],q[1],q[2],q[3],port);
 141                 }
 142         }
 143 }
 144
 145 /*
 146  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 147  * Print a general route file error
 148  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 149  */
 150 static void
 151 rerr(s,a)
 152 char *s;
 153 char *a;
 154 {
 155         (void)syslog(LOG_ERR,"Route file error at line %d:\n",rlineno);
 156         (void)syslog(LOG_ERR,s,a);
 157         rerrflag--;
 158 }
 159
 160 /*
 161  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 162  * Handle the "route" command
 163  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 164  */
 165 static void
 166 r_route()
 167 {
 168         int i, syntax;
 169         char *q;
 170         struct hostent *he;
 171
 172         if(rts_top>=MAX_ROUTES){
 173                 rerr("Too many routes defined","");
 174                 return;
 175         }
 176
 177         syntax = 0;
 178
 179         if((q = strtok((char *)NULL, " \t\n\r"))){
 180                 if((he = gethostbyname(q))){
 181                         (void)memcpy((char *)&rts[rts_top].ipaddr,
 182                                         he->h_addr_list[0], 4);
 183                 } else {
 184                         if((rts[rts_top].ipaddr = inet_addr(q)) == 0xffffffff)
 185                                 rerr("Bad IP address: %s",q);
 186                 }
 187         } else syntax++;
 188
 189         if((q = strtok((char *)NULL, " \t\n\r"))){
 190                 rts[rts_top].mask = htonl(strtoul(q, NULL, 0));
 191         } else syntax++;
 192
 193         if((q = strtok((char *)NULL, " \t\n\r"))){
 194                 for(i=0;i<ifs_top;i++){
 195                         if(strcmp(q,ifs[i].id)==0)rts[rts_top].destif = &ifs[i];
 196                 }
 197                 if(rts[rts_top].destif == NULL)
 198                         rerr("Interface %s not defined",q);
 199         } else syntax++;
 200
 201         if((q = strtok((char *)NULL, " \t\n\r"))){
 202                 if((he = gethostbyname(q))){
 203                         (void)memcpy((char *)&rts[rts_top].destaddr,
 204                                         he->h_addr_list[0], 4);
 205                 } else {
 206                         if((rts[rts_top].destaddr = inet_addr(q)) == (unsigned long)-1)
 207                                 rerr("Bad destination IP address: %s",q);
 208                 }
 209         }
 210
 211         if((q = strtok((char *)NULL, " \t\n\r"))){
 212                 rts[rts_top].destport = htons((unsigned short)atoi(q));
 213         }
 214
 215         if(syntax)rerr("Syntax error (route <ipaddr> <mask> <iface> [<destipaddr> [<destport>]]","");
 216
 217         rts_top++;
 218 }
 219
 220 static void
 221 sort_routes()
 222 {
 223         struct ipip_route *tmptable ;
 224         static unsigned long mask_entries[] = { \
 225         0xffffffff, 0xfffffffe, 0xfffffffc, 0xfffffff8,  \
 226         0xfffffff0, 0xffffffe0, 0xffffffc0, 0xffffff80,  \
 227         0xffffff00, 0xfffffe00, 0xfffffc00, 0xfffff800,  \
 228         0xfffff000, 0xffffe000, 0xffffc000, 0xffff8000,  \
 229         0xffff0000, 0xfffe0000, 0xfffc0000, 0xfff80000,  \
 230         0xfff00000, 0xffe00000, 0xffc00000, 0xff800000,  \
 231         0xff000000, 0xfe000000, 0xfc000000, 0xf8000000,  \
 232         0xf0000000, 0xe0000000, 0xc0000000, 0x80000000,  \
 233         0x00000000 } ;
 234         int i, j, newrows ;
 235
 236         tmptable = malloc ( (rts_top+1) * sizeof(struct ipip_route) ) ;
 237
 238         if (tmptable == NULL) {
 239                 rerr("Unable to allocate memory to resort table","");
 240                 return ;
 241         }
 242
 243         /* Search the original table 32 times for each of the 32 possible */
 244         /* masks.  Copy the most specific routes to the tmptable first    */
 245         newrows = 0;
 246         for ( i = 0 ; i <= 32 ; i++ )
 247                 for ( j = 0 ; j < rts_top ; j++ )
 248                         if (rts[j].mask == htonl(mask_entries[i]))
 249                                 tmptable[newrows++] = rts[j];
 250
 251         /* Copy the tmptable back to original */
 252         for ( i = 0 ; i < rts_top ; i++ )
 253                 rts[i] = tmptable[i] ;
 254         free (tmptable);
 255 }