Chris Vitale <cvs_at_bluetail.com>

diff --git a/extensions/ebt_802_3.c b/extensions/ebt_802_3.c
new file mode 100644 (file)
index 0000000..953a115
--- /dev/null
+++ b/extensions/ebt_802_3.c
@@ -0,0 +1,145 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include "../include/ebtables_u.h"
+#include "../include/ethernetdb.h"
+#include <linux/netfilter_bridge/ebt_802_3.h>
+
+#define _802_3_SAP '1'
+#define _802_3_TYPE '2'
+
+static struct option opts[] =
+{
+       { "802_3-sap"   , required_argument, 0, _802_3_SAP },
+       { "802_3-type"  , required_argument, 0, _802_3_TYPE },
+       { 0 }
+};
+
+static void print_help()
+{
+       printf(
+"802_3 options:\n"
+"--802_3-sap [!] protocol       : 802.3 DSAP/SSAP- 1 byte value (hex)\n"
+"  DSAP and SSAP are always the same.  One SAP applies to both fields\n"
+"--802_3-type [!] protocol      : 802.3 SNAP Type- 2 byte value (hex)\n"
+"  Type implies SAP value 0xaa\n");
+}
+
+static void init(struct ebt_entry_match *match)
+{
+       struct ebt_802_3_info *info = (struct ebt_802_3_info *)match->data;
+
+       info->invflags = 0;
+       info->bitmask = 0;
+}
+
+static int parse(int c, char **argv, int argc, const struct ebt_u_entry *entry,
+   unsigned int *flags, struct ebt_entry_match **match)
+{
+       struct ebt_802_3_info *info = (struct ebt_802_3_info *) (*match)->data;
+       unsigned int i;
+       char *end;
+
+       switch (c) {
+               case _802_3_SAP:
+                       check_option(flags, _802_3_SAP);
+                       if (check_inverse(optarg))
+                               info->invflags |= EBT_802_3_SAP;
+
+                       if (optind > argc)
+                               print_error("Missing 802.3-sap argument");
+                       i = strtoul(argv[optind - 1], &end, 16);
+                       if (i > 255 || *end != '\0') 
+                               print_error("Problem with specified "
+                                           "sap hex value, %x",i);
+                       info->sap = i; /* one byte, so no byte order worries */
+                       info->bitmask |= EBT_802_3_SAP;
+                       break;
+               case _802_3_TYPE:
+                       check_option(flags, _802_3_TYPE);
+                       if (check_inverse(optarg))
+                               info->invflags |= EBT_802_3_TYPE;
+                       if (optind > argc)
+                               print_error("Missing 802.3-type argument");
+                       i = strtoul(argv[optind - 1], &end, 16);
+                       if (i > 65535 || *end != '\0') {
+                               print_error("Problem with the specified "
+                                           "type hex value, %x",i);
+                       }
+                       info->type = htons(i);
+                       info->bitmask |= EBT_802_3_TYPE;
+                       break;
+               default:
+                       return 0;
+       }
+       return 1;
+}
+
+static void final_check(const struct ebt_u_entry *entry,
+   const struct ebt_entry_match *match, const char *name,
+   unsigned int hookmask, unsigned int time)
+{
+       if (!(entry->bitmask & EBT_802_3))
+               print_error("For 802.3 DSAP/SSAP filtering the protocol "
+                           "must be LENGTH");
+}
+
+static void print(const struct ebt_u_entry *entry,
+   const struct ebt_entry_match *match)
+{
+       struct ebt_802_3_info *info = (struct ebt_802_3_info *)match->data;
+
+       if (info->bitmask & EBT_802_3_SAP) {
+               printf("--802_3-sap ");
+               if (info->invflags & EBT_802_3_SAP)
+                       printf("! ");
+               printf("0x%.2x ", info->sap);
+       }
+       if (info->bitmask & EBT_802_3_TYPE) {
+               printf("--802_3-type ");
+               if (info->invflags & EBT_802_3_TYPE)
+                       printf("! ");
+               printf("0x%.4x ", ntohs(info->type));
+       }
+}
+
+static int compare(const struct ebt_entry_match *m1,
+   const struct ebt_entry_match *m2)
+{
+       struct ebt_802_3_info *info1 = (struct ebt_802_3_info *)m1->data;
+       struct ebt_802_3_info *info2 = (struct ebt_802_3_info *)m2->data;
+
+       if (info1->bitmask != info2->bitmask)
+               return 0;
+       if (info1->invflags != info2->invflags)
+               return 0;
+       if (info1->bitmask & EBT_802_3_SAP) {
+               if (info1->sap != info2->sap) 
+                       return 0;
+       }
+       if (info1->bitmask & EBT_802_3_TYPE) {
+               if (info1->type != info2->type)
+                       return 0;
+       }
+       return 1;
+}
+
+static struct ebt_u_match _802_3_match = 
+{
+       EBT_802_3_MATCH,
+       sizeof(struct ebt_802_3_info),
+       print_help,
+       init,
+       parse,
+       final_check,
+       print,
+       compare,
+       opts
+};
+
+static void _init(void) __attribute__ ((constructor));
+static void _init(void)
+{
+               register_match(&_802_3_match);
+}