1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170
|
/* Shared library add-on to iptables to add AH support. */
#include <stdio.h>
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include <getopt.h>
#include <errno.h>
#include <xtables.h>
#include <linux/netfilter_ipv4/ipt_ah.h>
static void ah_help(void)
{
printf(
"ah match options:\n"
"[!] --ahspi spi[:spi]\n"
" match spi (range)\n");
}
static const struct option ah_opts[] = {
{ "ahspi", 1, NULL, '1' },
{ .name = NULL }
};
static u_int32_t
parse_ah_spi(const char *spistr)
{
unsigned long int spi;
char* ep;
spi = strtoul(spistr,&ep,0) ;
if ( spistr == ep ) {
xtables_error(PARAMETER_PROBLEM,
"AH no valid digits in spi `%s'", spistr);
}
if ( spi == ULONG_MAX && errno == ERANGE ) {
xtables_error(PARAMETER_PROBLEM,
"spi `%s' specified too big: would overflow", spistr);
}
if ( *spistr != '\0' && *ep != '\0' ) {
xtables_error(PARAMETER_PROBLEM,
"AH error parsing spi `%s'", spistr);
}
return spi;
}
static void
parse_ah_spis(const char *spistring, u_int32_t *spis)
{
char *buffer;
char *cp;
buffer = strdup(spistring);
if ((cp = strchr(buffer, ':')) == NULL)
spis[0] = spis[1] = parse_ah_spi(buffer);
else {
*cp = '\0';
cp++;
spis[0] = buffer[0] ? parse_ah_spi(buffer) : 0;
spis[1] = cp[0] ? parse_ah_spi(cp) : 0xFFFFFFFF;
}
free(buffer);
}
static void ah_init(struct xt_entry_match *m)
{
struct ipt_ah *ahinfo = (struct ipt_ah *)m->data;
ahinfo->spis[1] = 0xFFFFFFFF;
}
#define AH_SPI 0x01
static int ah_parse(int c, char **argv, int invert, unsigned int *flags,
const void *entry, struct xt_entry_match **match)
{
struct ipt_ah *ahinfo = (struct ipt_ah *)(*match)->data;
switch (c) {
case '1':
if (*flags & AH_SPI)
xtables_error(PARAMETER_PROBLEM,
"Only one `--ahspi' allowed");
xtables_check_inverse(optarg, &invert, &optind, 0, argv);
parse_ah_spis(optarg, ahinfo->spis);
if (invert)
ahinfo->invflags |= IPT_AH_INV_SPI;
*flags |= AH_SPI;
break;
default:
return 0;
}
return 1;
}
static void
print_spis(const char *name, u_int32_t min, u_int32_t max,
int invert)
{
const char *inv = invert ? "!" : "";
if (min != 0 || max != 0xFFFFFFFF || invert) {
printf("%s", name);
if (min == max) {
printf(":%s", inv);
printf("%u", min);
} else {
printf("s:%s", inv);
printf("%u",min);
printf(":");
printf("%u",max);
}
printf(" ");
}
}
static void ah_print(const void *ip, const struct xt_entry_match *match,
int numeric)
{
const struct ipt_ah *ah = (struct ipt_ah *)match->data;
printf("ah ");
print_spis("spi", ah->spis[0], ah->spis[1],
ah->invflags & IPT_AH_INV_SPI);
if (ah->invflags & ~IPT_AH_INV_MASK)
printf("Unknown invflags: 0x%X ",
ah->invflags & ~IPT_AH_INV_MASK);
}
static void ah_save(const void *ip, const struct xt_entry_match *match)
{
const struct ipt_ah *ahinfo = (struct ipt_ah *)match->data;
if (!(ahinfo->spis[0] == 0
&& ahinfo->spis[1] == 0xFFFFFFFF)) {
printf("%s--ahspi ",
(ahinfo->invflags & IPT_AH_INV_SPI) ? "! " : "");
if (ahinfo->spis[0]
!= ahinfo->spis[1])
printf("%u:%u ",
ahinfo->spis[0],
ahinfo->spis[1]);
else
printf("%u ",
ahinfo->spis[0]);
}
}
static struct xtables_match ah_mt_reg = {
.name = "ah",
.version = XTABLES_VERSION,
.family = NFPROTO_IPV4,
.size = XT_ALIGN(sizeof(struct ipt_ah)),
.userspacesize = XT_ALIGN(sizeof(struct ipt_ah)),
.help = ah_help,
.init = ah_init,
.parse = ah_parse,
.print = ah_print,
.save = ah_save,
.extra_opts = ah_opts,
};
void
_init(void)
{
xtables_register_match(&ah_mt_reg);
}
|