1 /* Shared library add-on to iptables to add ESP support. */
9 #include <linux/netfilter_ipv4/ipt_esp.h>
11 /* Function which prints out usage message. */
17 " --espspi [!] spi[:spi]\n"
18 " match spi (range)\n",
22 static struct option opts[] = {
23 { "espspi", 1, 0, '1' },
28 parse_esp_spi(const char *spistr)
30 unsigned long int spi;
33 spi = strtoul(spistr,&ep,0) ;
36 exit_error(PARAMETER_PROBLEM,
37 "ESP no valid digits in spi `%s'", spistr);
39 if ( spi == ULONG_MAX && errno == ERANGE ) {
40 exit_error(PARAMETER_PROBLEM,
41 "spi `%s' specified too big: would overflow", spistr);
43 if ( *spistr != '\0' && *ep != '\0' ) {
44 exit_error(PARAMETER_PROBLEM,
45 "ESP error parsing spi `%s'", spistr);
47 return (u_int32_t) spi;
51 parse_esp_spis(const char *spistring, u_int32_t *spis)
56 buffer = strdup(spistring);
57 if ((cp = strchr(buffer, ':')) == NULL)
58 spis[0] = spis[1] = parse_esp_spi(buffer);
63 spis[0] = buffer[0] ? parse_esp_spi(buffer) : 0;
64 spis[1] = cp[0] ? parse_esp_spi(cp) : 0xFFFFFFFF;
65 if (spis[0] > spis[1])
66 exit_error(PARAMETER_PROBLEM,
67 "Invalid ESP spi range: %s", spistring);
72 /* Initialize the match. */
74 init(struct ipt_entry_match *m, unsigned int *nfcache)
76 struct ipt_esp *espinfo = (struct ipt_esp *)m->data;
78 espinfo->spis[1] = 0xFFFFFFFF;
83 /* Function which parses command options; returns true if it
86 parse(int c, char **argv, int invert, unsigned int *flags,
87 const struct ipt_entry *entry,
88 unsigned int *nfcache,
89 struct ipt_entry_match **match)
91 struct ipt_esp *espinfo = (struct ipt_esp *)(*match)->data;
96 exit_error(PARAMETER_PROBLEM,
97 "Only one `--espspi' allowed");
98 check_inverse(optarg, &invert, &optind, 0);
99 parse_esp_spis(argv[optind-1], espinfo->spis);
101 espinfo->invflags |= IPT_ESP_INV_SPI;
111 /* Final check; we don't care. */
113 final_check(unsigned int flags)
118 print_spis(const char *name, u_int32_t min, u_int32_t max,
121 const char *inv = invert ? "!" : "";
123 if (min != 0 || max != 0xFFFFFFFF || invert) {
138 /* Prints out the union ipt_matchinfo. */
140 print(const struct ipt_ip *ip,
141 const struct ipt_entry_match *match, int numeric)
143 const struct ipt_esp *esp = (struct ipt_esp *)match->data;
146 print_spis("spi", esp->spis[0], esp->spis[1],
147 esp->invflags & IPT_ESP_INV_SPI);
148 if (esp->invflags & ~IPT_ESP_INV_MASK)
149 printf("Unknown invflags: 0x%X ",
150 esp->invflags & ~IPT_ESP_INV_MASK);
153 /* Saves the union ipt_matchinfo in parsable form to stdout. */
154 static void save(const struct ipt_ip *ip, const struct ipt_entry_match *match)
156 const struct ipt_esp *espinfo = (struct ipt_esp *)match->data;
158 if (!(espinfo->spis[0] == 0
159 && espinfo->spis[1] == 0xFFFFFFFF)) {
160 printf("--espspi %s",
161 (espinfo->invflags & IPT_ESP_INV_SPI) ? "! " : "");
174 static struct iptables_match esp = {
177 .version = IPTABLES_VERSION,
178 .size = IPT_ALIGN(sizeof(struct ipt_esp)),
179 .userspacesize = IPT_ALIGN(sizeof(struct ipt_esp)),
183 .final_check = &final_check,
192 register_match(&esp);