Florian Westphal | 84c04e3 | 2018-04-10 10:55:30 +0200 | [diff] [blame] | 1 | /* ebt_nat |
| 2 | * |
| 3 | * Authors: |
| 4 | * Bart De Schuymer <bdschuym@pandora.be> |
| 5 | * |
| 6 | * June, 2002 |
| 7 | */ |
| 8 | |
| 9 | #include <stdio.h> |
| 10 | #include <stdlib.h> |
| 11 | #include <string.h> |
| 12 | #include <getopt.h> |
| 13 | #include <netinet/ether.h> |
| 14 | #include <xtables.h> |
| 15 | #include <linux/netfilter_bridge/ebt_nat.h> |
| 16 | #include "iptables/nft.h" |
| 17 | #include "iptables/nft-bridge.h" |
| 18 | |
| 19 | #define NAT_D '1' |
| 20 | #define NAT_D_TARGET '2' |
| 21 | static const struct option brdnat_opts[] = |
| 22 | { |
| 23 | { "to-destination", required_argument, 0, NAT_D }, |
| 24 | { "to-dst" , required_argument, 0, NAT_D }, |
| 25 | { "dnat-target" , required_argument, 0, NAT_D_TARGET }, |
| 26 | { 0 } |
| 27 | }; |
| 28 | |
| 29 | static void brdnat_print_help(void) |
| 30 | { |
| 31 | printf( |
| 32 | "dnat options:\n" |
| 33 | " --to-dst address : MAC address to map destination to\n" |
| 34 | " --dnat-target target : ACCEPT, DROP, RETURN or CONTINUE\n"); |
| 35 | } |
| 36 | |
| 37 | static void brdnat_init(struct xt_entry_target *target) |
| 38 | { |
| 39 | struct ebt_nat_info *natinfo = (struct ebt_nat_info *)target->data; |
| 40 | |
| 41 | natinfo->target = EBT_ACCEPT; |
| 42 | } |
| 43 | |
| 44 | #define OPT_DNAT 0x01 |
| 45 | #define OPT_DNAT_TARGET 0x02 |
| 46 | static int brdnat_parse(int c, char **argv, int invert, unsigned int *flags, |
| 47 | const void *entry, struct xt_entry_target **target) |
| 48 | { |
| 49 | struct ebt_nat_info *natinfo = (struct ebt_nat_info *)(*target)->data; |
| 50 | struct ether_addr *addr; |
| 51 | |
| 52 | switch (c) { |
| 53 | case NAT_D: |
| 54 | EBT_CHECK_OPTION(flags, OPT_DNAT); |
| 55 | if (!(addr = ether_aton(optarg))) |
| 56 | xtables_error(PARAMETER_PROBLEM, "Problem with specified --to-destination mac"); |
| 57 | memcpy(natinfo->mac, addr, ETH_ALEN); |
| 58 | break; |
| 59 | case NAT_D_TARGET: |
| 60 | EBT_CHECK_OPTION(flags, OPT_DNAT_TARGET); |
| 61 | if (ebt_fill_target(optarg, (unsigned int *)&natinfo->target)) |
| 62 | xtables_error(PARAMETER_PROBLEM, "Illegal --dnat-target target"); |
| 63 | break; |
| 64 | default: |
| 65 | return 0; |
| 66 | } |
| 67 | return 1; |
| 68 | } |
| 69 | |
| 70 | static void brdnat_final_check(unsigned int flags) |
| 71 | { |
| 72 | if (!flags) |
| 73 | xtables_error(PARAMETER_PROBLEM, |
| 74 | "You must specify proper arguments"); |
| 75 | } |
| 76 | |
Florian Westphal | 84c04e3 | 2018-04-10 10:55:30 +0200 | [diff] [blame] | 77 | static void brdnat_print(const void *ip, const struct xt_entry_target *target, int numeric) |
| 78 | { |
| 79 | struct ebt_nat_info *natinfo = (struct ebt_nat_info *)target->data; |
| 80 | |
| 81 | printf("--to-dst "); |
Florian Westphal | 7bd9feb | 2018-11-03 23:43:49 +0100 | [diff] [blame] | 82 | xtables_print_mac(natinfo->mac); |
Florian Westphal | 84c04e3 | 2018-04-10 10:55:30 +0200 | [diff] [blame] | 83 | printf(" --dnat-target %s", ebt_target_name(natinfo->target)); |
| 84 | } |
| 85 | |
| 86 | static const char* brdnat_verdict(int verdict) |
| 87 | { |
| 88 | switch (verdict) { |
| 89 | case EBT_ACCEPT: return "accept"; |
| 90 | case EBT_DROP: return "drop"; |
| 91 | case EBT_CONTINUE: return "continue"; |
| 92 | case EBT_RETURN: return "return"; |
| 93 | } |
| 94 | |
| 95 | return ""; |
| 96 | } |
| 97 | |
| 98 | static int brdnat_xlate(struct xt_xlate *xl, |
| 99 | const struct xt_xlate_tg_params *params) |
| 100 | { |
| 101 | const struct ebt_nat_info *natinfo = (const void*)params->target->data; |
| 102 | |
| 103 | xt_xlate_add(xl, "ether daddr set %s %s ", |
| 104 | ether_ntoa((struct ether_addr *)natinfo->mac), |
| 105 | brdnat_verdict(natinfo->target)); |
| 106 | |
| 107 | return 1; |
| 108 | } |
| 109 | |
| 110 | static struct xtables_target brdnat_target = |
| 111 | { |
| 112 | .name = "dnat", |
| 113 | .version = XTABLES_VERSION, |
| 114 | .family = NFPROTO_BRIDGE, |
| 115 | .size = XT_ALIGN(sizeof(struct ebt_nat_info)), |
| 116 | .userspacesize = XT_ALIGN(sizeof(struct ebt_nat_info)), |
| 117 | .help = brdnat_print_help, |
| 118 | .init = brdnat_init, |
| 119 | .parse = brdnat_parse, |
| 120 | .final_check = brdnat_final_check, |
| 121 | .print = brdnat_print, |
| 122 | .xlate = brdnat_xlate, |
| 123 | .extra_opts = brdnat_opts, |
| 124 | }; |
| 125 | |
| 126 | void _init(void) |
| 127 | { |
| 128 | xtables_register_target(&brdnat_target); |
| 129 | } |