From 8e0e25dfbafc28374bb76cdd748881eaaa353103 Mon Sep 17 00:00:00 2001 From: Bart De Schuymer Date: Mon, 12 May 2003 17:00:26 +0000 Subject: Chris Vitale --- extensions/ebt_802_3.c | 145 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 extensions/ebt_802_3.c (limited to 'extensions') diff --git a/extensions/ebt_802_3.c b/extensions/ebt_802_3.c new file mode 100644 index 0000000..953a115 --- /dev/null +++ b/extensions/ebt_802_3.c @@ -0,0 +1,145 @@ +#include +#include +#include +#include +#include "../include/ebtables_u.h" +#include "../include/ethernetdb.h" +#include + +#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); +} -- cgit v1.2.3