diff options
Diffstat (limited to 'extensions')
-rwxr-xr-x | extensions/.connbytes-test | 2 | ||||
-rw-r--r-- | extensions/libipt_connbytes.c | 134 |
2 files changed, 136 insertions, 0 deletions
diff --git a/extensions/.connbytes-test b/extensions/.connbytes-test new file mode 100755 index 0000000..350140f --- /dev/null +++ b/extensions/.connbytes-test @@ -0,0 +1,2 @@ +#! /bin/sh +[ -f $KERNEL_DIR/net/ipv4/netfilter/ipt_connbytes.c ] && echo connbytes diff --git a/extensions/libipt_connbytes.c b/extensions/libipt_connbytes.c new file mode 100644 index 0000000..abc37be --- /dev/null +++ b/extensions/libipt_connbytes.c @@ -0,0 +1,134 @@ +/* Shared library add-on to iptables to add byte tracking support. */ +#include <stdio.h> +#include <netdb.h> +#include <string.h> +#include <stdlib.h> +#include <getopt.h> +#include <iptables.h> +#include <linux/netfilter_ipv4/ip_conntrack.h> +#include <linux/netfilter_ipv4/ipt_connbytes.h> + +/* Function which prints out usage message. */ +static void +help(void) +{ + printf( +"connbytes v%s options:\n" +" [!] --connbytes from:[to]\n" +" Transfered byte range to match\n" +"\n", IPTABLES_VERSION); +} + +static struct option opts[] = { + { "connbytes", 1, 0, '1' }, + {0} +}; + +/* Initialize the match. */ +static void +init(struct ipt_entry_match *m, unsigned int *nfcache) +{ + /* Can't cache this */ + *nfcache |= NFC_UNKNOWN; +} + +static void +parse_range(const char *arg, struct ipt_connbytes_info *si) +{ + char *colon,*p; + + si->from = strtol(arg,&colon,10); + if (*colon != ':') + exit_error(PARAMETER_PROBLEM, "Bad range `%s'", arg); + si->to = strtol(colon+1,&p,10); + if (p == colon+1) { + /* second number omited */ + si->to = 0xffffffff; + } + if (si->from > si->to) + exit_error(PARAMETER_PROBLEM, "%lu should be less than %lu", si->from,si->to); +} + +/* 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_connbytes_info *sinfo = (struct ipt_connbytes_info *)(*match)->data; + int i; + + switch (c) { + case '1': + if (check_inverse(optarg, &invert, optind, 0)) + optind++; + + parse_range(argv[optind-1], sinfo); + if (invert) { + i = sinfo->from; + sinfo->from = sinfo->to; + sinfo->to = i; + } + *flags = 1; + break; + + default: + return 0; + } + + return 1; +} + +static void final_check(unsigned int flags) +{ + if (!flags) + exit_error(PARAMETER_PROBLEM, "You must specify `--connbytes'"); +} + +/* Prints out the matchinfo. */ +static void +print(const struct ipt_ip *ip, + const struct ipt_entry_match *match, + int numeric) +{ + struct ipt_connbytes_info *sinfo = (struct ipt_connbytes_info *)match->data; + + if (sinfo->from > sinfo->to) + printf("connbytes ! %lu:%lu",sinfo->to,sinfo->from); + else + printf("connbytes %lu:%lu",sinfo->from,sinfo->to); +} + +/* Saves the matchinfo in parsable form to stdout. */ +static void save(const struct ipt_ip *ip, const struct ipt_entry_match *match) +{ + struct ipt_connbytes_info *sinfo = (struct ipt_connbytes_info *)match->data; + + if (sinfo->from > sinfo->to) + printf("! --connbytes %lu:%lu",sinfo->to,sinfo->from); + else + printf("--connbytes %lu:%lu",sinfo->from,sinfo->to); +} + +static +struct iptables_match state += { NULL, + "connbytes", + IPTABLES_VERSION, + IPT_ALIGN(sizeof(struct ipt_connbytes_info)), + IPT_ALIGN(sizeof(struct ipt_connbytes_info)), + &help, + &init, + &parse, + &final_check, + &print, + &save, + opts +}; + +void _init(void) +{ + register_match(&state); +} |