Harald Welte | 18f1aff | 2001-03-25 19:03:23 +0000 | [diff] [blame] | 1 | /* Shared library add-on to iptables to add simple non load-balancing SNAT support. */ |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 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_tables.h> |
Patrick McHardy | 40d5475 | 2007-04-18 07:00:36 +0000 | [diff] [blame] | 9 | #include <linux/netfilter/nf_nat.h> |
Martin Josefsson | 1eb0081 | 2004-05-26 15:58:07 +0000 | [diff] [blame] | 10 | /* For 64bit kernel / 32bit userspace */ |
| 11 | #include "../include/linux/netfilter_ipv4/ipt_SAME.h" |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 12 | |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 13 | /* Function which prints out usage message. */ |
| 14 | static void |
| 15 | help(void) |
| 16 | { |
| 17 | printf( |
| 18 | "SAME v%s options:\n" |
Harald Welte | 18f1aff | 2001-03-25 19:03:23 +0000 | [diff] [blame] | 19 | " --to <ipaddr>-<ipaddr>\n" |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 20 | " Addresses to map source to.\n" |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 21 | " May be specified more than\n" |
| 22 | " once for multiple ranges.\n" |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 23 | " --nodst\n" |
| 24 | " Don't use destination-ip in\n" |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 25 | " source selection\n" |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 26 | " --random\n" |
| 27 | " Randomize source port\n" |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 28 | , |
Harald Welte | 80fe35d | 2002-05-29 13:08:15 +0000 | [diff] [blame] | 29 | IPTABLES_VERSION); |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 30 | } |
| 31 | |
| 32 | static struct option opts[] = { |
Harald Welte | 18f1aff | 2001-03-25 19:03:23 +0000 | [diff] [blame] | 33 | { "to", 1, 0, '1' }, |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 34 | { "nodst", 0, 0, '2'}, |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 35 | { "random", 0, 0, '3' }, |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 36 | { 0 } |
| 37 | }; |
| 38 | |
| 39 | /* Initialize the target. */ |
| 40 | static void |
| 41 | init(struct ipt_entry_target *t, unsigned int *nfcache) |
| 42 | { |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 43 | struct ipt_same_info *mr = (struct ipt_same_info *)t->data; |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 44 | |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 45 | /* Set default to 0 */ |
| 46 | mr->rangesize = 0; |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 47 | mr->info = 0; |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 48 | mr->ipnum = 0; |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 49 | |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 50 | } |
| 51 | |
| 52 | /* Parses range of IPs */ |
| 53 | static void |
| 54 | parse_to(char *arg, struct ip_nat_range *range) |
| 55 | { |
| 56 | char *dash; |
| 57 | struct in_addr *ip; |
| 58 | |
| 59 | range->flags |= IP_NAT_RANGE_MAP_IPS; |
| 60 | dash = strchr(arg, '-'); |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 61 | |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 62 | if (dash) |
| 63 | *dash = '\0'; |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 64 | |
| 65 | ip = dotted_to_addr(arg); |
| 66 | if (!ip) |
| 67 | exit_error(PARAMETER_PROBLEM, "Bad IP address `%s'\n", |
| 68 | arg); |
| 69 | range->min_ip = ip->s_addr; |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 70 | |
| 71 | if (dash) { |
| 72 | ip = dotted_to_addr(dash+1); |
| 73 | if (!ip) |
| 74 | exit_error(PARAMETER_PROBLEM, "Bad IP address `%s'\n", |
| 75 | dash+1); |
| 76 | } |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 77 | range->max_ip = ip->s_addr; |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 78 | if (dash) |
| 79 | if (range->min_ip > range->max_ip) |
| 80 | exit_error(PARAMETER_PROBLEM, "Bad IP range `%s-%s'\n", |
| 81 | arg, dash+1); |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 82 | } |
| 83 | |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 84 | #define IPT_SAME_OPT_TO 0x01 |
| 85 | #define IPT_SAME_OPT_NODST 0x02 |
Patrick McHardy | e656e26 | 2007-04-18 12:56:05 +0000 | [diff] [blame] | 86 | #define IPT_SAME_OPT_RANDOM 0x04 |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 87 | |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 88 | /* Function which parses command options; returns true if it |
| 89 | ate an option */ |
| 90 | static int |
| 91 | parse(int c, char **argv, int invert, unsigned int *flags, |
| 92 | const struct ipt_entry *entry, |
| 93 | struct ipt_entry_target **target) |
| 94 | { |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 95 | struct ipt_same_info *mr |
| 96 | = (struct ipt_same_info *)(*target)->data; |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 97 | int count; |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 98 | |
| 99 | switch (c) { |
| 100 | case '1': |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 101 | if (mr->rangesize == IPT_SAME_MAX_RANGE) |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 102 | exit_error(PARAMETER_PROBLEM, |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 103 | "Too many ranges specified, maximum " |
| 104 | "is %i ranges.\n", |
| 105 | IPT_SAME_MAX_RANGE); |
Harald Welte | b77f1da | 2002-03-14 11:35:58 +0000 | [diff] [blame] | 106 | if (check_inverse(optarg, &invert, NULL, 0)) |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 107 | exit_error(PARAMETER_PROBLEM, |
Harald Welte | 18f1aff | 2001-03-25 19:03:23 +0000 | [diff] [blame] | 108 | "Unexpected `!' after --to"); |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 109 | |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 110 | parse_to(optarg, &mr->range[mr->rangesize]); |
Patrick McHardy | e656e26 | 2007-04-18 12:56:05 +0000 | [diff] [blame] | 111 | /* WTF do we need this for? */ |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 112 | if (*flags & IPT_SAME_OPT_RANDOM) |
| 113 | mr->range[mr->rangesize].flags |
| 114 | |= IP_NAT_RANGE_PROTO_RANDOM; |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 115 | mr->rangesize++; |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 116 | *flags |= IPT_SAME_OPT_TO; |
| 117 | break; |
| 118 | |
| 119 | case '2': |
| 120 | if (*flags & IPT_SAME_OPT_NODST) |
| 121 | exit_error(PARAMETER_PROBLEM, |
| 122 | "Can't specify --nodst twice"); |
| 123 | |
| 124 | mr->info |= IPT_SAME_NODST; |
| 125 | *flags |= IPT_SAME_OPT_NODST; |
| 126 | break; |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 127 | |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 128 | case '3': |
| 129 | *flags |= IPT_SAME_OPT_RANDOM; |
| 130 | for (count=0; count < mr->rangesize; count++) |
| 131 | mr->range[count].flags |= IP_NAT_RANGE_PROTO_RANDOM; |
| 132 | break; |
Patrick McHardy | e656e26 | 2007-04-18 12:56:05 +0000 | [diff] [blame] | 133 | |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 134 | default: |
| 135 | return 0; |
| 136 | } |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 137 | |
| 138 | return 1; |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 139 | } |
| 140 | |
Harald Welte | 18f1aff | 2001-03-25 19:03:23 +0000 | [diff] [blame] | 141 | /* Final check; need --to. */ |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 142 | static void final_check(unsigned int flags) |
| 143 | { |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 144 | if (!(flags & IPT_SAME_OPT_TO)) |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 145 | exit_error(PARAMETER_PROBLEM, |
Harald Welte | 18f1aff | 2001-03-25 19:03:23 +0000 | [diff] [blame] | 146 | "SAME needs --to"); |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 147 | } |
| 148 | |
| 149 | /* Prints out the targinfo. */ |
| 150 | static void |
| 151 | print(const struct ipt_ip *ip, |
| 152 | const struct ipt_entry_target *target, |
| 153 | int numeric) |
| 154 | { |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 155 | int count; |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 156 | struct ipt_same_info *mr |
| 157 | = (struct ipt_same_info *)target->data; |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 158 | int random = 0; |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 159 | |
| 160 | printf("same:"); |
| 161 | |
| 162 | for (count = 0; count < mr->rangesize; count++) { |
| 163 | struct ip_nat_range *r = &mr->range[count]; |
| 164 | struct in_addr a; |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 165 | |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 166 | a.s_addr = r->min_ip; |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 167 | |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 168 | printf("%s", addr_to_dotted(&a)); |
| 169 | a.s_addr = r->max_ip; |
| 170 | |
| 171 | if (r->min_ip == r->max_ip) |
| 172 | printf(" "); |
| 173 | else |
| 174 | printf("-%s ", addr_to_dotted(&a)); |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 175 | if (r->flags & IP_NAT_RANGE_PROTO_RANDOM) |
| 176 | random = 1; |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 177 | } |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 178 | |
| 179 | if (mr->info & IPT_SAME_NODST) |
| 180 | printf("nodst "); |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 181 | |
Eric Leblond | ae4b0b3 | 2007-02-24 15:11:33 +0000 | [diff] [blame] | 182 | if (random) |
| 183 | printf("random "); |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 184 | } |
| 185 | |
| 186 | /* Saves the union ipt_targinfo in parsable form to stdout. */ |
| 187 | static void |
| 188 | save(const struct ipt_ip *ip, const struct ipt_entry_target *target) |
| 189 | { |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 190 | int count; |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 191 | struct ipt_same_info *mr |
| 192 | = (struct ipt_same_info *)target->data; |
Patrick McHardy | 9c67def | 2007-04-18 14:00:11 +0000 | [diff] [blame] | 193 | int random = 0; |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 194 | |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 195 | for (count = 0; count < mr->rangesize; count++) { |
| 196 | struct ip_nat_range *r = &mr->range[count]; |
| 197 | struct in_addr a; |
| 198 | |
| 199 | a.s_addr = r->min_ip; |
| 200 | printf("--to %s", addr_to_dotted(&a)); |
| 201 | a.s_addr = r->max_ip; |
| 202 | |
| 203 | if (r->min_ip == r->max_ip) |
| 204 | printf(" "); |
| 205 | else |
| 206 | printf("-%s ", addr_to_dotted(&a)); |
Patrick McHardy | 9c67def | 2007-04-18 14:00:11 +0000 | [diff] [blame] | 207 | if (r->flags & IP_NAT_RANGE_PROTO_RANDOM) |
| 208 | random = 1; |
Harald Welte | 05e0b01 | 2001-08-26 08:18:25 +0000 | [diff] [blame] | 209 | } |
Harald Welte | cf655eb | 2001-07-28 18:47:11 +0000 | [diff] [blame] | 210 | |
| 211 | if (mr->info & IPT_SAME_NODST) |
| 212 | printf("--nodst "); |
Patrick McHardy | 9c67def | 2007-04-18 14:00:11 +0000 | [diff] [blame] | 213 | |
| 214 | if (random) |
| 215 | printf("--random "); |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 216 | } |
| 217 | |
Pablo Neira | 8caee8b | 2004-12-28 13:11:59 +0000 | [diff] [blame] | 218 | static struct iptables_target same = { |
| 219 | .next = NULL, |
| 220 | .name = "SAME", |
| 221 | .version = IPTABLES_VERSION, |
| 222 | .size = IPT_ALIGN(sizeof(struct ipt_same_info)), |
| 223 | .userspacesize = IPT_ALIGN(sizeof(struct ipt_same_info)), |
| 224 | .help = &help, |
| 225 | .init = &init, |
| 226 | .parse = &parse, |
| 227 | .final_check = &final_check, |
| 228 | .print = &print, |
| 229 | .save = &save, |
| 230 | .extra_opts = opts |
Martin Josefsson | f419f75 | 2001-02-19 21:55:27 +0000 | [diff] [blame] | 231 | }; |
| 232 | |
| 233 | void _init(void) |
| 234 | { |
| 235 | register_target(&same); |
| 236 | } |