blob: 2a91416530a4f1cebda0268394e694d316e53a7b [file] [log] [blame]
/* 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));
}