userapps/opensource/ebtables/extensions/ebt_pkttype.c

   1 /*
   2  *  ebtables ebt_pkttype
   3  *
   4  *  Authors:
   5  *   Bart De Schuymer <bdschuym@pandora.be>
   6  *
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <getopt.h>
  13 #include <netdb.h>
  14 #include "../include/ebtables_u.h"
  15 #include <linux/if_packet.h>
  16 #include <linux/netfilter_bridge/ebt_pkttype.h>
  17
  18 char *classes[] =
  19 {
  20         "host",
  21         "broadcast",
  22         "multicast",
  23         "otherhost",
  24         "outgoing",
  25         "loopback",
  26         "fastroute",
  27         "\0"
  28 };
  29
  30 static struct option opts[] =
  31 {
  32         { "pkttype-type"        , required_argument, 0, '1' },
  33         { 0 }
  34 };
  35
  36 static void print_help()
  37 {
  38         printf(
  39 "pkttype options:\n"
  40 "--pkttype-type    [!] type: class the packet belongs to\n"
  41 "Possible values: broadcast, multicast, host, otherhost any byte value.\n");
  42 }
  43
  44 static void init(struct ebt_entry_match *match)
  45 {
  46         struct ebt_pkttype_info *pt = (struct ebt_pkttype_info *)match->data;
  47
  48         pt->invert = 0;
  49 }
  50
  51 static int parse(int c, char **argv, int argc, const struct ebt_u_entry *entry,
  52    unsigned int *flags, struct ebt_entry_match **match)
  53 {
  54         struct ebt_pkttype_info *ptinfo = (struct ebt_pkttype_info *)(*match)->data;
  55         char *end;
  56         long int i;
  57
  58         switch (c) {
  59         case '1':
  60                 check_option(flags, 1);
  61                 if (check_inverse(optarg))
  62                         ptinfo->invert = 1;
  63                 if (optind > argc)
  64                         print_error("Missing pkttype class specification");
  65
  66                 i = strtol(argv[optind - 1], &end, 16);
  67                 if (*end != '\0') {
  68                         int j = 0;
  69                         i = -1;
  70                         while (classes[j][0])
  71                                 if (!strcasecmp(argv[optind - 1], classes[j++])) {
  72                                         i = j - 1;
  73                                         break;
  74                                 }
  75                 }
  76                 if (i < 0 || i > 255)
  77                         print_error("Problem with specified pkttype class");
  78                 ptinfo->pkt_type = (uint8_t)i;
  79
  80                 break;
  81         default:
  82                 return 0;
  83         }
  84         return 1;
  85 }
  86
  87 static void final_check(const struct ebt_u_entry *entry,
  88    const struct ebt_entry_match *match, const char *name,
  89    unsigned int hookmask, unsigned int time)
  90 {
  91 }
  92
  93 static void print(const struct ebt_u_entry *entry,
  94    const struct ebt_entry_match *match)
  95 {
  96         struct ebt_pkttype_info *pt = (struct ebt_pkttype_info *)match->data;
  97         int i = 0;
  98
  99         printf("--pkttype-type %s", pt->invert ? "! " : "");
 100         while (classes[i++][0]);
 101         if (pt->pkt_type < i - 1)
 102                 printf("%s ", classes[pt->pkt_type]);
 103         else
 104                 printf("%d ", pt->pkt_type);
 105 }
 106
 107 static int compare(const struct ebt_entry_match *m1,
 108    const struct ebt_entry_match *m2)
 109 {
 110         struct ebt_pkttype_info *pt1 = (struct ebt_pkttype_info *)m1->data;
 111         struct ebt_pkttype_info *pt2 = (struct ebt_pkttype_info *)m2->data;
 112
 113         if (pt1->invert != pt2->invert ||
 114             pt1->pkt_type != pt2->pkt_type)
 115                 return 0;
 116         return 1;
 117 }
 118
 119 static struct ebt_u_match pkttype_match =
 120 {
 121         .name           = EBT_PKTTYPE_MATCH,
 122         .size           = sizeof(struct ebt_pkttype_info),
 123         .help           = print_help,
 124         .init           = init,
 125         .parse          = parse,
 126         .final_check    = final_check,
 127         .print          = print,
 128         .compare        = compare,
 129         .extra_ops      = opts,
 130 };
 131
 132 static void _init(void) __attribute((constructor));
 133 static void _init(void)
 134 {
 135         register_match(&pkttype_match);
 136 }