diff options
Diffstat (limited to 'extensions/libipt_childlevel.c')
-rw-r--r-- | extensions/libipt_childlevel.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/extensions/libipt_childlevel.c b/extensions/libipt_childlevel.c new file mode 100644 index 0000000..bc9f0ad --- /dev/null +++ b/extensions/libipt_childlevel.c @@ -0,0 +1,122 @@ +/* + Shared library add-on to iptables to add layer 7 matching support. + + http://l7-filter.sf.net + + By Matthew Strait <quadong@users.sf.net>, Dec 2003. + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License + as published by the Free Software Foundation; either version + 2 of the License, or (at your option) any later version. + http://www.gnu.org/licenses/gpl.txt +*/ + +#define _GNU_SOURCE +#include <stdio.h> +#include <netdb.h> +#include <string.h> +#include <stdlib.h> +#include <getopt.h> +#include <ctype.h> +#include <dirent.h> + +#include <iptables.h> +#include <linux/netfilter_ipv4/ipt_childlevel.h> + +/* Function which prints out usage message. */ +static void help(void) +{ + printf( + "CHILDLEVEL match v%s options:\n" + "--level <n> : Match childlevel n (0 == master)\n", + IPTABLES_VERSION); + fputc('\n', stdout); +} + +static struct option opts[] = { + { .name = "level", .has_arg = 1, .flag = 0, .val = '1' }, + { .name = 0 } +}; + +/* Initialize the match. */ +static void init(struct ipt_entry_match *m, unsigned int *nfcache) +{ + *nfcache |= NFC_UNKNOWN; +} + +/* Function which parses command options; returns true if it ate an option */ +static int parse(int c, char **argv, int invert, unsigned int *flags, + const struct ipt_entry *entry, unsigned int *nfcache, + struct ipt_entry_match **match) +{ + struct ipt_childlevel_info *childlevelinfo = + (struct ipt_childlevel_info *)(*match)->data; + + switch (c) { + case '1': + check_inverse(optarg, &invert, &optind, 0); + childlevelinfo->childlevel = atoi(argv[optind-1]); + if (invert) + childlevelinfo->invert = 1; + *flags = 1; + break; + default: + return 0; + } + + return 1; +} + +/* Final check; must have specified --level. */ +static void final_check(unsigned int flags) +{ + if (!flags) + exit_error(PARAMETER_PROBLEM, + "CHILDLEVEL match: You must specify `--level'"); +} + +static void print_protocol(int n, int invert, int numeric) +{ + fputs("childlevel ", stdout); + if (invert) fputc('!', stdout); + printf("%d ", n); +} + +/* Prints out the matchinfo. */ +static void print(const struct ipt_ip *ip, + const struct ipt_entry_match *match, + int numeric) +{ + printf("CHILDLEVEL "); + + print_protocol(((struct ipt_childlevel_info *)match->data)->childlevel, + ((struct ipt_childlevel_info *)match->data)->invert, numeric); +} +/* Saves the union ipt_matchinfo in parsable form to stdout. */ +static void save(const struct ipt_ip *ip, const struct ipt_entry_match *match) +{ + const struct ipt_childlevel_info *info = + (const struct ipt_childlevel_info*) match->data; + + printf("--childlevel %s%d ", (info->invert) ? "! ": "", info->childlevel); +} + +static struct iptables_match childlevel = { + .name = "childlevel", + .version = IPTABLES_VERSION, + .size = IPT_ALIGN(sizeof(struct ipt_childlevel_info)), + .userspacesize = IPT_ALIGN(sizeof(struct ipt_childlevel_info)), + .help = &help, + .init = &init, + .parse = &parse, + .final_check = &final_check, + .print = &print, + .save = &save, + .extra_opts = opts +}; + +void _init(void) +{ + register_match(&childlevel); +} |