| Martin Devera | 766113a | 2003-06-19 12:23:37 +0000 | [diff] [blame^] | 1 | /* Shared library add-on to iptables to add byte tracking support. */ |
| 2 | #include <stdio.h> |
| 3 | #include <netdb.h> |
| 4 | #include <string.h> |
| 5 | #include <stdlib.h> |
| 6 | #include <getopt.h> |
| 7 | #include <iptables.h> |
| 8 | #include <linux/netfilter_ipv4/ip_conntrack.h> |
| 9 | #include <linux/netfilter_ipv4/ipt_connbytes.h> |
| 10 | |
| 11 | /* Function which prints out usage message. */ |
| 12 | static void |
| 13 | help(void) |
| 14 | { |
| 15 | printf( |
| 16 | "connbytes v%s options:\n" |
| 17 | " [!] --connbytes from:[to]\n" |
| 18 | " Transfered byte range to match\n" |
| 19 | "\n", IPTABLES_VERSION); |
| 20 | } |
| 21 | |
| 22 | static struct option opts[] = { |
| 23 | { "connbytes", 1, 0, '1' }, |
| 24 | {0} |
| 25 | }; |
| 26 | |
| 27 | /* Initialize the match. */ |
| 28 | static void |
| 29 | init(struct ipt_entry_match *m, unsigned int *nfcache) |
| 30 | { |
| 31 | /* Can't cache this */ |
| 32 | *nfcache |= NFC_UNKNOWN; |
| 33 | } |
| 34 | |
| 35 | static void |
| 36 | parse_range(const char *arg, struct ipt_connbytes_info *si) |
| 37 | { |
| 38 | char *colon,*p; |
| 39 | |
| 40 | si->from = strtol(arg,&colon,10); |
| 41 | if (*colon != ':') |
| 42 | exit_error(PARAMETER_PROBLEM, "Bad range `%s'", arg); |
| 43 | si->to = strtol(colon+1,&p,10); |
| 44 | if (p == colon+1) { |
| 45 | /* second number omited */ |
| 46 | si->to = 0xffffffff; |
| 47 | } |
| 48 | if (si->from > si->to) |
| 49 | exit_error(PARAMETER_PROBLEM, "%lu should be less than %lu", si->from,si->to); |
| 50 | } |
| 51 | |
| 52 | /* Function which parses command options; returns true if it |
| 53 | ate an option */ |
| 54 | static int |
| 55 | parse(int c, char **argv, int invert, unsigned int *flags, |
| 56 | const struct ipt_entry *entry, |
| 57 | unsigned int *nfcache, |
| 58 | struct ipt_entry_match **match) |
| 59 | { |
| 60 | struct ipt_connbytes_info *sinfo = (struct ipt_connbytes_info *)(*match)->data; |
| 61 | int i; |
| 62 | |
| 63 | switch (c) { |
| 64 | case '1': |
| 65 | if (check_inverse(optarg, &invert, optind, 0)) |
| 66 | optind++; |
| 67 | |
| 68 | parse_range(argv[optind-1], sinfo); |
| 69 | if (invert) { |
| 70 | i = sinfo->from; |
| 71 | sinfo->from = sinfo->to; |
| 72 | sinfo->to = i; |
| 73 | } |
| 74 | *flags = 1; |
| 75 | break; |
| 76 | |
| 77 | default: |
| 78 | return 0; |
| 79 | } |
| 80 | |
| 81 | return 1; |
| 82 | } |
| 83 | |
| 84 | static void final_check(unsigned int flags) |
| 85 | { |
| 86 | if (!flags) |
| 87 | exit_error(PARAMETER_PROBLEM, "You must specify `--connbytes'"); |
| 88 | } |
| 89 | |
| 90 | /* Prints out the matchinfo. */ |
| 91 | static void |
| 92 | print(const struct ipt_ip *ip, |
| 93 | const struct ipt_entry_match *match, |
| 94 | int numeric) |
| 95 | { |
| 96 | struct ipt_connbytes_info *sinfo = (struct ipt_connbytes_info *)match->data; |
| 97 | |
| 98 | if (sinfo->from > sinfo->to) |
| 99 | printf("connbytes ! %lu:%lu",sinfo->to,sinfo->from); |
| 100 | else |
| 101 | printf("connbytes %lu:%lu",sinfo->from,sinfo->to); |
| 102 | } |
| 103 | |
| 104 | /* Saves the matchinfo in parsable form to stdout. */ |
| 105 | static void save(const struct ipt_ip *ip, const struct ipt_entry_match *match) |
| 106 | { |
| 107 | struct ipt_connbytes_info *sinfo = (struct ipt_connbytes_info *)match->data; |
| 108 | |
| 109 | if (sinfo->from > sinfo->to) |
| 110 | printf("! --connbytes %lu:%lu",sinfo->to,sinfo->from); |
| 111 | else |
| 112 | printf("--connbytes %lu:%lu",sinfo->from,sinfo->to); |
| 113 | } |
| 114 | |
| 115 | static |
| 116 | struct iptables_match state |
| 117 | = { NULL, |
| 118 | "connbytes", |
| 119 | IPTABLES_VERSION, |
| 120 | IPT_ALIGN(sizeof(struct ipt_connbytes_info)), |
| 121 | IPT_ALIGN(sizeof(struct ipt_connbytes_info)), |
| 122 | &help, |
| 123 | &init, |
| 124 | &parse, |
| 125 | &final_check, |
| 126 | &print, |
| 127 | &save, |
| 128 | opts |
| 129 | }; |
| 130 | |
| 131 | void _init(void) |
| 132 | { |
| 133 | register_match(&state); |
| 134 | } |