1
/* Shared library add-on to iptables for SCTP matching
3
* (C) 2003 by Harald Welte <laforge@gnumonks.org>
5
* This program is distributed under the terms of GNU GPL v2, 1991
7
* libipt_ecn.c borrowed heavily from libipt_dscp.c
17
#include <ip6tables.h>
18
#include <linux/netfilter_ipv6/ip6_tables.h>
21
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
24
#include <linux/netfilter/xt_sctp.h>
26
/* Some ZS!#@:$%*#$! has replaced the ELEMCOUNT macro in ipt_sctp.h with
27
* ARRAY_SIZE without noticing that this file is used from userserspace,
28
* and userspace doesn't have ARRAY_SIZE */
31
#define ELEMCOUNT ARRAY_SIZE
35
#define DEBUGP(format, first...) printf(format, ##first)
38
#define DEBUGP(format, fist...)
42
print_chunk(u_int32_t chunknum, int numeric);
44
/* Initialize the match. */
46
init(struct ip6t_entry_match *m,
47
unsigned int *nfcache)
50
struct xt_sctp_info *einfo = (struct xt_sctp_info *)m->data;
52
memset(einfo, 0, sizeof(struct xt_sctp_info));
54
for (i = 0; i < XT_NUM_SCTP_FLAGS; i++) {
55
einfo->flag_info[i].chunktype = -1;
59
static void help(void)
62
"SCTP match v%s options\n"
63
" --source-port [!] port[:port] match source port(s)\n"
65
" --destination-port [!] port[:port] match destination port(s)\n"
67
" --chunk-types [!] (all|any|none) (chunktype[:flags])+ match if all, any or none of\n"
68
" chunktypes are present\n"
69
"chunktypes - DATA INIT INIT_ACK SACK HEARTBEAT HEARTBEAT_ACK ABORT SHUTDOWN SHUTDOWN_ACK ERROR COOKIE_ECHO COOKIE_ACK ECN_ECNE ECN_CWR SHUTDOWN_COMPLETE ASCONF ASCONF_ACK ALL NONE\n",
73
static struct option opts[] = {
74
{ .name = "source-port", .has_arg = 1, .flag = 0, .val = '1' },
75
{ .name = "sport", .has_arg = 1, .flag = 0, .val = '1' },
76
{ .name = "destination-port", .has_arg = 1, .flag = 0, .val = '2' },
77
{ .name = "dport", .has_arg = 1, .flag = 0, .val = '2' },
78
{ .name = "chunk-types", .has_arg = 1, .flag = 0, .val = '3' },
83
parse_sctp_ports(const char *portstring,
89
buffer = strdup(portstring);
90
DEBUGP("%s\n", portstring);
91
if ((cp = strchr(buffer, ':')) == NULL) {
92
ports[0] = ports[1] = parse_port(buffer, "sctp");
98
ports[0] = buffer[0] ? parse_port(buffer, "sctp") : 0;
99
ports[1] = cp[0] ? parse_port(cp, "sctp") : 0xFFFF;
101
if (ports[0] > ports[1])
102
exit_error(PARAMETER_PROBLEM,
103
"invalid portrange (min > max)");
108
struct sctp_chunk_names {
110
unsigned int chunk_type;
111
const char *valid_flags;
114
/*'ALL' and 'NONE' will be treated specially. */
115
static struct sctp_chunk_names sctp_chunk_names[]
116
= { { .name = "DATA", .chunk_type = 0, .valid_flags = "-----UBE"},
117
{ .name = "INIT", .chunk_type = 1, .valid_flags = "--------"},
118
{ .name = "INIT_ACK", .chunk_type = 2, .valid_flags = "--------"},
119
{ .name = "SACK", .chunk_type = 3, .valid_flags = "--------"},
120
{ .name = "HEARTBEAT", .chunk_type = 4, .valid_flags = "--------"},
121
{ .name = "HEARTBEAT_ACK", .chunk_type = 5, .valid_flags = "--------"},
122
{ .name = "ABORT", .chunk_type = 6, .valid_flags = "-------T"},
123
{ .name = "SHUTDOWN", .chunk_type = 7, .valid_flags = "--------"},
124
{ .name = "SHUTDOWN_ACK", .chunk_type = 8, .valid_flags = "--------"},
125
{ .name = "ERROR", .chunk_type = 9, .valid_flags = "--------"},
126
{ .name = "COOKIE_ECHO", .chunk_type = 10, .valid_flags = "--------"},
127
{ .name = "COOKIE_ACK", .chunk_type = 11, .valid_flags = "--------"},
128
{ .name = "ECN_ECNE", .chunk_type = 12, .valid_flags = "--------"},
129
{ .name = "ECN_CWR", .chunk_type = 13, .valid_flags = "--------"},
130
{ .name = "SHUTDOWN_COMPLETE", .chunk_type = 14, .valid_flags = "-------T"},
131
{ .name = "ASCONF", .chunk_type = 31, .valid_flags = "--------"},
132
{ .name = "ASCONF_ACK", .chunk_type = 30, .valid_flags = "--------"},
136
save_chunk_flag_info(struct xt_sctp_flag_info *flag_info,
144
for (i = 0; i < *flag_count; i++) {
145
if (flag_info[i].chunktype == chunktype) {
146
DEBUGP("Previous match found\n");
147
flag_info[i].chunktype = chunktype;
148
flag_info[i].flag_mask |= (1 << bit);
150
flag_info[i].flag |= (1 << bit);
157
if (*flag_count == XT_NUM_SCTP_FLAGS) {
158
exit_error (PARAMETER_PROBLEM,
159
"Number of chunk types with flags exceeds currently allowed limit."
160
"Increasing this limit involves changing XT_NUM_SCTP_FLAGS and"
161
"recompiling both the kernel space and user space modules\n");
164
flag_info[*flag_count].chunktype = chunktype;
165
flag_info[*flag_count].flag_mask |= (1 << bit);
167
flag_info[*flag_count].flag |= (1 << bit);
173
parse_sctp_chunk(struct xt_sctp_info *einfo,
182
buffer = strdup(chunks);
183
DEBUGP("Buffer: %s\n", buffer);
185
SCTP_CHUNKMAP_RESET(einfo->chunkmap);
187
if (!strcasecmp(buffer, "ALL")) {
188
SCTP_CHUNKMAP_SET_ALL(einfo->chunkmap);
192
if (!strcasecmp(buffer, "NONE")) {
193
SCTP_CHUNKMAP_RESET(einfo->chunkmap);
197
for (ptr = strtok(buffer, ","); ptr; ptr = strtok(NULL, ",")) {
199
DEBUGP("Next Chunk type %s\n", ptr);
201
if ((chunk_flags = strchr(ptr, ':')) != NULL) {
205
for (i = 0; i < ELEMCOUNT(sctp_chunk_names); i++) {
206
if (strcasecmp(sctp_chunk_names[i].name, ptr) == 0) {
207
DEBUGP("Chunk num %d\n", sctp_chunk_names[i].chunk_type);
208
SCTP_CHUNKMAP_SET(einfo->chunkmap,
209
sctp_chunk_names[i].chunk_type);
215
exit_error(PARAMETER_PROBLEM,
216
"Unknown sctp chunk `%s'", ptr);
219
DEBUGP("Chunk flags %s\n", chunk_flags);
220
for (j = 0; j < strlen(chunk_flags); j++) {
224
if ((p = strchr(sctp_chunk_names[i].valid_flags,
225
toupper(chunk_flags[j]))) != NULL) {
226
bit = p - sctp_chunk_names[i].valid_flags;
229
save_chunk_flag_info(einfo->flag_info,
230
&(einfo->flag_count), i, bit,
231
isupper(chunk_flags[j]));
233
exit_error(PARAMETER_PROBLEM,
234
"Invalid flags for chunk type %d\n", i);
244
parse_sctp_chunks(struct xt_sctp_info *einfo,
245
const char *match_type,
248
DEBUGP("Match type: %s Chunks: %s\n", match_type, chunks);
249
if (!strcasecmp(match_type, "ANY")) {
250
einfo->chunk_match_type = SCTP_CHUNK_MATCH_ANY;
251
} else if (!strcasecmp(match_type, "ALL")) {
252
einfo->chunk_match_type = SCTP_CHUNK_MATCH_ALL;
253
} else if (!strcasecmp(match_type, "ONLY")) {
254
einfo->chunk_match_type = SCTP_CHUNK_MATCH_ONLY;
256
exit_error (PARAMETER_PROBLEM,
257
"Match type has to be one of \"ALL\", \"ANY\" or \"ONLY\"");
260
SCTP_CHUNKMAP_RESET(einfo->chunkmap);
261
parse_sctp_chunk(einfo, chunks);
265
parse(int c, char **argv, int invert, unsigned int *flags,
266
const struct ip6t_entry *entry,
267
unsigned int *nfcache,
268
struct ip6t_entry_match **match)
270
struct xt_sctp_info *einfo
271
= (struct xt_sctp_info *)(*match)->data;
275
if (*flags & XT_SCTP_SRC_PORTS)
276
exit_error(PARAMETER_PROBLEM,
277
"Only one `--source-port' allowed");
278
einfo->flags |= XT_SCTP_SRC_PORTS;
279
check_inverse(optarg, &invert, &optind, 0);
280
parse_sctp_ports(argv[optind-1], einfo->spts);
282
einfo->invflags |= XT_SCTP_SRC_PORTS;
283
*flags |= XT_SCTP_SRC_PORTS;
287
if (*flags & XT_SCTP_DEST_PORTS)
288
exit_error(PARAMETER_PROBLEM,
289
"Only one `--destination-port' allowed");
290
einfo->flags |= XT_SCTP_DEST_PORTS;
291
check_inverse(optarg, &invert, &optind, 0);
292
parse_sctp_ports(argv[optind-1], einfo->dpts);
294
einfo->invflags |= XT_SCTP_DEST_PORTS;
295
*flags |= XT_SCTP_DEST_PORTS;
299
if (*flags & XT_SCTP_CHUNK_TYPES)
300
exit_error(PARAMETER_PROBLEM,
301
"Only one `--chunk-types' allowed");
302
check_inverse(optarg, &invert, &optind, 0);
305
|| argv[optind][0] == '-' || argv[optind][0] == '!')
306
exit_error(PARAMETER_PROBLEM,
307
"--chunk-types requires two args");
309
einfo->flags |= XT_SCTP_CHUNK_TYPES;
310
parse_sctp_chunks(einfo, argv[optind-1], argv[optind]);
312
einfo->invflags |= XT_SCTP_CHUNK_TYPES;
314
*flags |= XT_SCTP_CHUNK_TYPES;
324
final_check(unsigned int flags)
329
port_to_service(int port)
331
struct servent *service;
333
if ((service = getservbyport(htons(port), "sctp")))
334
return service->s_name;
340
print_port(u_int16_t port, int numeric)
344
if (numeric || (service = port_to_service(port)) == NULL)
347
printf("%s", service);
351
print_ports(const char *name, u_int16_t min, u_int16_t max,
352
int invert, int numeric)
354
const char *inv = invert ? "!" : "";
356
if (min != 0 || max != 0xFFFF || invert) {
360
print_port(min, numeric);
363
print_port(min, numeric);
365
print_port(max, numeric);
372
print_chunk_flags(u_int32_t chunknum, u_int8_t chunk_flags, u_int8_t chunk_flags_mask)
376
DEBUGP("type: %d\tflags: %x\tflag mask: %x\n", chunknum, chunk_flags,
379
if (chunk_flags_mask) {
383
for (i = 7; i >= 0; i--) {
384
if (chunk_flags_mask & (1 << i)) {
385
if (chunk_flags & (1 << i)) {
386
printf("%c", sctp_chunk_names[chunknum].valid_flags[7-i]);
388
printf("%c", tolower(sctp_chunk_names[chunknum].valid_flags[7-i]));
395
print_chunk(u_int32_t chunknum, int numeric)
398
printf("0x%04X", chunknum);
403
for (i = 0; i < ELEMCOUNT(sctp_chunk_names); i++) {
404
if (sctp_chunk_names[i].chunk_type == chunknum)
405
printf("%s", sctp_chunk_names[chunknum].name);
411
print_chunks(u_int32_t chunk_match_type,
412
const u_int32_t *chunkmap,
413
const struct xt_sctp_flag_info *flag_info,
420
switch (chunk_match_type) {
421
case SCTP_CHUNK_MATCH_ANY: printf("any "); break;
422
case SCTP_CHUNK_MATCH_ALL: printf("all "); break;
423
case SCTP_CHUNK_MATCH_ONLY: printf("only "); break;
424
default: printf("Never reach herer\n"); break;
427
if (SCTP_CHUNKMAP_IS_CLEAR(chunkmap)) {
432
if (SCTP_CHUNKMAP_IS_ALL_SET(chunkmap)) {
438
for (i = 0; i < 256; i++) {
439
if (SCTP_CHUNKMAP_IS_SET(chunkmap, i)) {
443
print_chunk(i, numeric);
444
for (j = 0; j < flag_count; j++) {
445
if (flag_info[j].chunktype == i) {
446
print_chunk_flags(i, flag_info[j].flag,
447
flag_info[j].flag_mask);
459
/* Prints out the matchinfo. */
461
print(const struct ip6t_ip6 *ip,
462
const struct ip6t_entry_match *match,
465
const struct xt_sctp_info *einfo =
466
(const struct xt_sctp_info *)match->data;
470
if (einfo->flags & XT_SCTP_SRC_PORTS) {
471
print_ports("spt", einfo->spts[0], einfo->spts[1],
472
einfo->invflags & XT_SCTP_SRC_PORTS,
476
if (einfo->flags & XT_SCTP_DEST_PORTS) {
477
print_ports("dpt", einfo->dpts[0], einfo->dpts[1],
478
einfo->invflags & XT_SCTP_DEST_PORTS,
482
if (einfo->flags & XT_SCTP_CHUNK_TYPES) {
483
/* FIXME: print_chunks() is used in save() where the printing of '!'
484
s taken care of, so we need to do that here as well */
485
if (einfo->invflags & XT_SCTP_CHUNK_TYPES) {
488
print_chunks(einfo->chunk_match_type, einfo->chunkmap,
489
einfo->flag_info, einfo->flag_count, numeric);
493
/* Saves the union xt_matchinfo in parsable form to stdout. */
495
save(const struct ip6t_ip6 *ip,
496
const struct ip6t_entry_match *match)
498
const struct xt_sctp_info *einfo =
499
(const struct xt_sctp_info *)match->data;
501
if (einfo->flags & XT_SCTP_SRC_PORTS) {
502
if (einfo->invflags & XT_SCTP_SRC_PORTS)
504
if (einfo->spts[0] != einfo->spts[1])
505
printf("--sport %u:%u ",
506
einfo->spts[0], einfo->spts[1]);
508
printf("--sport %u ", einfo->spts[0]);
511
if (einfo->flags & XT_SCTP_DEST_PORTS) {
512
if (einfo->invflags & XT_SCTP_DEST_PORTS)
514
if (einfo->dpts[0] != einfo->dpts[1])
515
printf("--dport %u:%u ",
516
einfo->dpts[0], einfo->dpts[1]);
518
printf("--dport %u ", einfo->dpts[0]);
521
if (einfo->flags & XT_SCTP_CHUNK_TYPES) {
522
if (einfo->invflags & XT_SCTP_CHUNK_TYPES)
524
printf("--chunk-types ");
526
print_chunks(einfo->chunk_match_type, einfo->chunkmap,
527
einfo->flag_info, einfo->flag_count, 0);
532
struct ip6tables_match sctp
534
.version = IPTABLES_VERSION,
535
.size = IP6T_ALIGN(sizeof(struct xt_sctp_info)),
536
.userspacesize = IP6T_ALIGN(sizeof(struct xt_sctp_info)),
540
.final_check = &final_check,
548
register_match6(&sctp);