| /* Shared library add-on to iptables to add IP range matching support. */ |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <netdb.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <getopt.h> |
| |
| #include <netinet/in.h> |
| #include <xtables.h> |
| #include <linux/netfilter.h> |
| #include <linux/netfilter/xt_iprange.h> |
| |
| struct ipt_iprange { |
| /* Inclusive: network order. */ |
| __be32 min_ip, max_ip; |
| }; |
| |
| struct ipt_iprange_info { |
| struct ipt_iprange src; |
| struct ipt_iprange dst; |
| |
| /* Flags from above */ |
| uint8_t flags; |
| }; |
| |
| enum { |
| F_SRCIP = 1 << 0, |
| F_DSTIP = 1 << 1, |
| }; |
| |
| static void iprange_mt_help(void) |
| { |
| printf( |
| "iprange match options:\n" |
| "[!] --src-range ip[-ip] Match source IP in the specified range\n" |
| "[!] --dst-range ip[-ip] Match destination IP in the specified range\n"); |
| } |
| |
| static const struct option iprange_mt_opts[] = { |
| {.name = "src-range", .has_arg = true, .val = '1'}, |
| {.name = "dst-range", .has_arg = true, .val = '2'}, |
| XT_GETOPT_TABLEEND, |
| }; |
| |
| static void |
| iprange_parse_spec(const char *from, const char *to, union nf_inet_addr *range, |
| uint8_t family, const char *optname) |
| { |
| const char *spec[2] = {from, to}; |
| struct in6_addr *ia6; |
| struct in_addr *ia4; |
| unsigned int i; |
| |
| memset(range, 0, sizeof(union nf_inet_addr) * 2); |
| |
| if (family == NFPROTO_IPV6) { |
| for (i = 0; i < ARRAY_SIZE(spec); ++i) { |
| ia6 = xtables_numeric_to_ip6addr(spec[i]); |
| if (ia6 == NULL) |
| xtables_param_act(XTF_BAD_VALUE, "iprange", |
| optname, spec[i]); |
| range[i].in6 = *ia6; |
| } |
| } else { |
| for (i = 0; i < ARRAY_SIZE(spec); ++i) { |
| ia4 = xtables_numeric_to_ipaddr(spec[i]); |
| if (ia4 == NULL) |
| xtables_param_act(XTF_BAD_VALUE, "iprange", |
| optname, spec[i]); |
| range[i].in = *ia4; |
| } |
| } |
| } |
| |
| static void iprange_parse_range(char *arg, union nf_inet_addr *range, |
| uint8_t family, const char *optname) |
| { |
| char *dash; |
| |
| dash = strchr(arg, '-'); |
| if (dash == NULL) { |
| iprange_parse_spec(arg, arg, range, family, optname); |
| return; |
| } |
| |
| *dash = '\0'; |
| iprange_parse_spec(arg, dash + 1, range, family, optname); |
| if (memcmp(&range[0], &range[1], sizeof(*range)) > 0) |
| fprintf(stderr, "xt_iprange: range %s-%s is reversed and " |
| "will never match\n", arg, dash + 1); |
| } |
| |
| static int iprange_parse(int c, char **argv, int invert, unsigned int *flags, |
| const void *entry, struct xt_entry_match **match) |
| { |
| struct ipt_iprange_info *info = (struct ipt_iprange_info *)(*match)->data; |
| union nf_inet_addr range[2]; |
| |
| switch (c) { |
| case '1': |
| if (*flags & IPRANGE_SRC) |
| xtables_error(PARAMETER_PROBLEM, |
| "iprange match: Only use --src-range ONCE!"); |
| *flags |= IPRANGE_SRC; |
| |
| info->flags |= IPRANGE_SRC; |
| xtables_check_inverse(optarg, &invert, &optind, 0, argv); |
| if (invert) |
| info->flags |= IPRANGE_SRC_INV; |
| iprange_parse_range(optarg, range, NFPROTO_IPV4, "--src-range"); |
| info->src.min_ip = range[0].ip; |
| info->src.max_ip = range[1].ip; |
| break; |
| |
| case '2': |
| if (*flags & IPRANGE_DST) |
| xtables_error(PARAMETER_PROBLEM, |
| "iprange match: Only use --dst-range ONCE!"); |
| *flags |= IPRANGE_DST; |
| |
| info->flags |= IPRANGE_DST; |
| xtables_check_inverse(optarg, &invert, &optind, 0, argv); |
| if (invert) |
| info->flags |= IPRANGE_DST_INV; |
| |
| iprange_parse_range(optarg, range, NFPROTO_IPV4, "--dst-range"); |
| info->dst.min_ip = range[0].ip; |
| info->dst.max_ip = range[1].ip; |
| break; |
| } |
| return 1; |
| } |
| |
| static int |
| iprange_mt4_parse(int c, char **argv, int invert, unsigned int *flags, |
| const void *entry, struct xt_entry_match **match) |
| { |
| struct xt_iprange_mtinfo *info = (void *)(*match)->data; |
| |
| switch (c) { |
| case '1': /* --src-range */ |
| iprange_parse_range(optarg, &info->src_min, NFPROTO_IPV4, |
| "--src-range"); |
| info->flags |= IPRANGE_SRC; |
| if (invert) |
| info->flags |= IPRANGE_SRC_INV; |
| *flags |= F_SRCIP; |
| return true; |
| |
| case '2': /* --dst-range */ |
| iprange_parse_range(optarg, &info->dst_min, NFPROTO_IPV4, |
| "--dst-range"); |
| info->flags |= IPRANGE_DST; |
| if (invert) |
| info->flags |= IPRANGE_DST_INV; |
| *flags |= F_DSTIP; |
| return true; |
| } |
| return false; |
| } |
| |
| static int |
| iprange_mt6_parse(int c, char **argv, int invert, unsigned int *flags, |
| const void *entry, struct xt_entry_match **match) |
| { |
| struct xt_iprange_mtinfo *info = (void *)(*match)->data; |
| |
| switch (c) { |
| case '1': /* --src-range */ |
| iprange_parse_range(optarg, &info->src_min, NFPROTO_IPV6, |
| "--src-range"); |
| info->flags |= IPRANGE_SRC; |
| if (invert) |
| info->flags |= IPRANGE_SRC_INV; |
| *flags |= F_SRCIP; |
| return true; |
| |
| case '2': /* --dst-range */ |
| iprange_parse_range(optarg, &info->dst_min, NFPROTO_IPV6, |
| "--dst-range"); |
| info->flags |= IPRANGE_DST; |
| if (invert) |
| info->flags |= IPRANGE_DST_INV; |
| *flags |= F_DSTIP; |
| return true; |
| } |
| return false; |
| } |
| |
| static void iprange_mt_check(unsigned int flags) |
| { |
| if (flags == 0) |
| xtables_error(PARAMETER_PROBLEM, |
| "iprange match: You must specify `--src-range' or `--dst-range'"); |
| } |
| |
| static void |
| print_iprange(const struct ipt_iprange *range) |
| { |
| const unsigned char *byte_min, *byte_max; |
| |
| byte_min = (const unsigned char *)&range->min_ip; |
| byte_max = (const unsigned char *)&range->max_ip; |
| printf(" %u.%u.%u.%u-%u.%u.%u.%u", |
| byte_min[0], byte_min[1], byte_min[2], byte_min[3], |
| byte_max[0], byte_max[1], byte_max[2], byte_max[3]); |
| } |
| |
| static void iprange_print(const void *ip, const struct xt_entry_match *match, |
| int numeric) |
| { |
| const struct ipt_iprange_info *info = (const void *)match->data; |
| |
| if (info->flags & IPRANGE_SRC) { |
| printf(" source IP range"); |
| if (info->flags & IPRANGE_SRC_INV) |
| printf(" !"); |
| print_iprange(&info->src); |
| } |
| if (info->flags & IPRANGE_DST) { |
| printf(" destination IP range"); |
| if (info->flags & IPRANGE_DST_INV) |
| printf(" !"); |
| print_iprange(&info->dst); |
| } |
| } |
| |
| static void |
| iprange_mt4_print(const void *ip, const struct xt_entry_match *match, |
| int numeric) |
| { |
| const struct xt_iprange_mtinfo *info = (const void *)match->data; |
| |
| if (info->flags & IPRANGE_SRC) { |
| printf(" source IP range"); |
| if (info->flags & IPRANGE_SRC_INV) |
| printf(" !"); |
| /* |
| * ipaddr_to_numeric() uses a static buffer, so cannot |
| * combine the printf() calls. |
| */ |
| printf(" %s", xtables_ipaddr_to_numeric(&info->src_min.in)); |
| printf("-%s", xtables_ipaddr_to_numeric(&info->src_max.in)); |
| } |
| if (info->flags & IPRANGE_DST) { |
| printf(" destination IP range"); |
| if (info->flags & IPRANGE_DST_INV) |
| printf(" !"); |
| printf(" %s", xtables_ipaddr_to_numeric(&info->dst_min.in)); |
| printf("-%s", xtables_ipaddr_to_numeric(&info->dst_max.in)); |
| } |
| } |
| |
| static void |
| iprange_mt6_print(const void *ip, const struct xt_entry_match *match, |
| int numeric) |
| { |
| const struct xt_iprange_mtinfo *info = (const void *)match->data; |
| |
| if (info->flags & IPRANGE_SRC) { |
| printf(" source IP range"); |
| if (info->flags & IPRANGE_SRC_INV) |
| printf(" !"); |
| /* |
| * ipaddr_to_numeric() uses a static buffer, so cannot |
| * combine the printf() calls. |
| */ |
| printf(" %s", xtables_ip6addr_to_numeric(&info->src_min.in6)); |
| printf("-%s", xtables_ip6addr_to_numeric(&info->src_max.in6)); |
| } |
| if (info->flags & IPRANGE_DST) { |
| printf(" destination IP range"); |
| if (info->flags & IPRANGE_DST_INV) |
| printf(" !"); |
| printf(" %s", xtables_ip6addr_to_numeric(&info->dst_min.in6)); |
| printf("-%s", xtables_ip6addr_to_numeric(&info->dst_max.in6)); |
| } |
| } |
| |
| static void iprange_save(const void *ip, const struct xt_entry_match *match) |
| { |
| const struct ipt_iprange_info *info = (const void *)match->data; |
| |
| if (info->flags & IPRANGE_SRC) { |
| if (info->flags & IPRANGE_SRC_INV) |
| printf(" !"); |
| printf(" --src-range"); |
| print_iprange(&info->src); |
| } |
| if (info->flags & IPRANGE_DST) { |
| if (info->flags & IPRANGE_DST_INV) |
| printf(" !"); |
| printf(" --dst-range"); |
| print_iprange(&info->dst); |
| } |
| } |
| |
| static void iprange_mt4_save(const void *ip, const struct xt_entry_match *match) |
| { |
| const struct xt_iprange_mtinfo *info = (const void *)match->data; |
| |
| if (info->flags & IPRANGE_SRC) { |
| if (info->flags & IPRANGE_SRC_INV) |
| printf(" !"); |
| printf(" --src-range %s", xtables_ipaddr_to_numeric(&info->src_min.in)); |
| printf("-%s", xtables_ipaddr_to_numeric(&info->src_max.in)); |
| } |
| if (info->flags & IPRANGE_DST) { |
| if (info->flags & IPRANGE_DST_INV) |
| printf(" !"); |
| printf(" --dst-range %s", xtables_ipaddr_to_numeric(&info->dst_min.in)); |
| printf("-%s", xtables_ipaddr_to_numeric(&info->dst_max.in)); |
| } |
| } |
| |
| static void iprange_mt6_save(const void *ip, const struct xt_entry_match *match) |
| { |
| const struct xt_iprange_mtinfo *info = (const void *)match->data; |
| |
| if (info->flags & IPRANGE_SRC) { |
| if (info->flags & IPRANGE_SRC_INV) |
| printf(" !"); |
| printf(" --src-range %s", xtables_ip6addr_to_numeric(&info->src_min.in6)); |
| printf("-%s", xtables_ip6addr_to_numeric(&info->src_max.in6)); |
| } |
| if (info->flags & IPRANGE_DST) { |
| if (info->flags & IPRANGE_DST_INV) |
| printf(" !"); |
| printf(" --dst-range %s", xtables_ip6addr_to_numeric(&info->dst_min.in6)); |
| printf("-%s", xtables_ip6addr_to_numeric(&info->dst_max.in6)); |
| } |
| } |
| |
| static struct xtables_match iprange_mt_reg[] = { |
| { |
| .version = XTABLES_VERSION, |
| .name = "iprange", |
| .revision = 0, |
| .family = NFPROTO_IPV4, |
| .size = XT_ALIGN(sizeof(struct ipt_iprange_info)), |
| .userspacesize = XT_ALIGN(sizeof(struct ipt_iprange_info)), |
| .help = iprange_mt_help, |
| .parse = iprange_parse, |
| .final_check = iprange_mt_check, |
| .print = iprange_print, |
| .save = iprange_save, |
| .extra_opts = iprange_mt_opts, |
| }, |
| { |
| .version = XTABLES_VERSION, |
| .name = "iprange", |
| .revision = 1, |
| .family = NFPROTO_IPV4, |
| .size = XT_ALIGN(sizeof(struct xt_iprange_mtinfo)), |
| .userspacesize = XT_ALIGN(sizeof(struct xt_iprange_mtinfo)), |
| .help = iprange_mt_help, |
| .parse = iprange_mt4_parse, |
| .final_check = iprange_mt_check, |
| .print = iprange_mt4_print, |
| .save = iprange_mt4_save, |
| .extra_opts = iprange_mt_opts, |
| }, |
| { |
| .version = XTABLES_VERSION, |
| .name = "iprange", |
| .revision = 1, |
| .family = NFPROTO_IPV6, |
| .size = XT_ALIGN(sizeof(struct xt_iprange_mtinfo)), |
| .userspacesize = XT_ALIGN(sizeof(struct xt_iprange_mtinfo)), |
| .help = iprange_mt_help, |
| .parse = iprange_mt6_parse, |
| .final_check = iprange_mt_check, |
| .print = iprange_mt6_print, |
| .save = iprange_mt6_save, |
| .extra_opts = iprange_mt_opts, |
| }, |
| }; |
| |
| void _init(void) |
| { |
| xtables_register_matches(iprange_mt_reg, ARRAY_SIZE(iprange_mt_reg)); |
| } |
