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1 | /* FTP extension for connection tracking. */ | |
2 | ||
3 | /* (C) 1999-2001 Paul `Rusty' Russell | |
4 | * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> | |
5 | * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | #include <linux/moduleparam.h> | |
14 | #include <linux/netfilter.h> | |
15 | #include <linux/ip.h> | |
16 | #include <linux/ipv6.h> | |
17 | #include <linux/ctype.h> | |
18 | #include <linux/inet.h> | |
19 | #include <net/checksum.h> | |
20 | #include <net/tcp.h> | |
21 | ||
22 | #include <net/netfilter/nf_conntrack.h> | |
23 | #include <net/netfilter/nf_conntrack_expect.h> | |
24 | #include <net/netfilter/nf_conntrack_ecache.h> | |
25 | #include <net/netfilter/nf_conntrack_helper.h> | |
26 | #include <linux/netfilter/nf_conntrack_ftp.h> | |
27 | ||
28 | MODULE_LICENSE("GPL"); | |
29 | MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>"); | |
30 | MODULE_DESCRIPTION("ftp connection tracking helper"); | |
31 | MODULE_ALIAS("ip_conntrack_ftp"); | |
32 | ||
33 | /* This is slow, but it's simple. --RR */ | |
34 | static char *ftp_buffer; | |
35 | ||
36 | static DEFINE_SPINLOCK(nf_ftp_lock); | |
37 | ||
38 | #define MAX_PORTS 8 | |
39 | static u_int16_t ports[MAX_PORTS]; | |
40 | static unsigned int ports_c; | |
41 | module_param_array(ports, ushort, &ports_c, 0400); | |
42 | ||
43 | static int loose; | |
44 | module_param(loose, bool, 0600); | |
45 | ||
46 | unsigned int (*nf_nat_ftp_hook)(struct sk_buff *skb, | |
47 | enum ip_conntrack_info ctinfo, | |
48 | enum nf_ct_ftp_type type, | |
49 | unsigned int matchoff, | |
50 | unsigned int matchlen, | |
51 | struct nf_conntrack_expect *exp); | |
52 | EXPORT_SYMBOL_GPL(nf_nat_ftp_hook); | |
53 | ||
54 | static int try_rfc959(const char *, size_t, struct nf_conntrack_man *, char); | |
55 | static int try_eprt(const char *, size_t, struct nf_conntrack_man *, char); | |
56 | static int try_epsv_response(const char *, size_t, struct nf_conntrack_man *, | |
57 | char); | |
58 | ||
59 | static struct ftp_search { | |
60 | const char *pattern; | |
61 | size_t plen; | |
62 | char skip; | |
63 | char term; | |
64 | enum nf_ct_ftp_type ftptype; | |
65 | int (*getnum)(const char *, size_t, struct nf_conntrack_man *, char); | |
66 | } search[IP_CT_DIR_MAX][2] = { | |
67 | [IP_CT_DIR_ORIGINAL] = { | |
68 | { | |
69 | .pattern = "PORT", | |
70 | .plen = sizeof("PORT") - 1, | |
71 | .skip = ' ', | |
72 | .term = '\r', | |
73 | .ftptype = NF_CT_FTP_PORT, | |
74 | .getnum = try_rfc959, | |
75 | }, | |
76 | { | |
77 | .pattern = "EPRT", | |
78 | .plen = sizeof("EPRT") - 1, | |
79 | .skip = ' ', | |
80 | .term = '\r', | |
81 | .ftptype = NF_CT_FTP_EPRT, | |
82 | .getnum = try_eprt, | |
83 | }, | |
84 | }, | |
85 | [IP_CT_DIR_REPLY] = { | |
86 | { | |
87 | .pattern = "227 ", | |
88 | .plen = sizeof("227 ") - 1, | |
89 | .skip = '(', | |
90 | .term = ')', | |
91 | .ftptype = NF_CT_FTP_PASV, | |
92 | .getnum = try_rfc959, | |
93 | }, | |
94 | { | |
95 | .pattern = "229 ", | |
96 | .plen = sizeof("229 ") - 1, | |
97 | .skip = '(', | |
98 | .term = ')', | |
99 | .ftptype = NF_CT_FTP_EPSV, | |
100 | .getnum = try_epsv_response, | |
101 | }, | |
102 | }, | |
103 | }; | |
104 | ||
105 | static int | |
106 | get_ipv6_addr(const char *src, size_t dlen, struct in6_addr *dst, u_int8_t term) | |
107 | { | |
108 | const char *end; | |
109 | int ret = in6_pton(src, min_t(size_t, dlen, 0xffff), (u8 *)dst, term, &end); | |
110 | if (ret > 0) | |
111 | return (int)(end - src); | |
112 | return 0; | |
113 | } | |
114 | ||
115 | static int try_number(const char *data, size_t dlen, u_int32_t array[], | |
116 | int array_size, char sep, char term) | |
117 | { | |
118 | u_int32_t i, len; | |
119 | ||
120 | memset(array, 0, sizeof(array[0])*array_size); | |
121 | ||
122 | /* Keep data pointing at next char. */ | |
123 | for (i = 0, len = 0; len < dlen && i < array_size; len++, data++) { | |
124 | if (*data >= '0' && *data <= '9') { | |
125 | array[i] = array[i]*10 + *data - '0'; | |
126 | } | |
127 | else if (*data == sep) | |
128 | i++; | |
129 | else { | |
130 | /* Unexpected character; true if it's the | |
131 | terminator and we're finished. */ | |
132 | if (*data == term && i == array_size - 1) | |
133 | return len; | |
134 | ||
135 | pr_debug("Char %u (got %u nums) `%u' unexpected\n", | |
136 | len, i, *data); | |
137 | return 0; | |
138 | } | |
139 | } | |
140 | pr_debug("Failed to fill %u numbers separated by %c\n", | |
141 | array_size, sep); | |
142 | return 0; | |
143 | } | |
144 | ||
145 | /* Returns 0, or length of numbers: 192,168,1,1,5,6 */ | |
146 | static int try_rfc959(const char *data, size_t dlen, | |
147 | struct nf_conntrack_man *cmd, char term) | |
148 | { | |
149 | int length; | |
150 | u_int32_t array[6]; | |
151 | ||
152 | length = try_number(data, dlen, array, 6, ',', term); | |
153 | if (length == 0) | |
154 | return 0; | |
155 | ||
156 | cmd->u3.ip = htonl((array[0] << 24) | (array[1] << 16) | | |
157 | (array[2] << 8) | array[3]); | |
158 | cmd->u.tcp.port = htons((array[4] << 8) | array[5]); | |
159 | return length; | |
160 | } | |
161 | ||
162 | /* Grab port: number up to delimiter */ | |
163 | static int get_port(const char *data, int start, size_t dlen, char delim, | |
164 | __be16 *port) | |
165 | { | |
166 | u_int16_t tmp_port = 0; | |
167 | int i; | |
168 | ||
169 | for (i = start; i < dlen; i++) { | |
170 | /* Finished? */ | |
171 | if (data[i] == delim) { | |
172 | if (tmp_port == 0) | |
173 | break; | |
174 | *port = htons(tmp_port); | |
175 | pr_debug("get_port: return %d\n", tmp_port); | |
176 | return i + 1; | |
177 | } | |
178 | else if (data[i] >= '0' && data[i] <= '9') | |
179 | tmp_port = tmp_port*10 + data[i] - '0'; | |
180 | else { /* Some other crap */ | |
181 | pr_debug("get_port: invalid char.\n"); | |
182 | break; | |
183 | } | |
184 | } | |
185 | return 0; | |
186 | } | |
187 | ||
188 | /* Returns 0, or length of numbers: |1|132.235.1.2|6275| or |2|3ffe::1|6275| */ | |
189 | static int try_eprt(const char *data, size_t dlen, struct nf_conntrack_man *cmd, | |
190 | char term) | |
191 | { | |
192 | char delim; | |
193 | int length; | |
194 | ||
195 | /* First character is delimiter, then "1" for IPv4 or "2" for IPv6, | |
196 | then delimiter again. */ | |
197 | if (dlen <= 3) { | |
198 | pr_debug("EPRT: too short\n"); | |
199 | return 0; | |
200 | } | |
201 | delim = data[0]; | |
202 | if (isdigit(delim) || delim < 33 || delim > 126 || data[2] != delim) { | |
203 | pr_debug("try_eprt: invalid delimitter.\n"); | |
204 | return 0; | |
205 | } | |
206 | ||
207 | if ((cmd->l3num == PF_INET && data[1] != '1') || | |
208 | (cmd->l3num == PF_INET6 && data[1] != '2')) { | |
209 | pr_debug("EPRT: invalid protocol number.\n"); | |
210 | return 0; | |
211 | } | |
212 | ||
213 | pr_debug("EPRT: Got %c%c%c\n", delim, data[1], delim); | |
214 | ||
215 | if (data[1] == '1') { | |
216 | u_int32_t array[4]; | |
217 | ||
218 | /* Now we have IP address. */ | |
219 | length = try_number(data + 3, dlen - 3, array, 4, '.', delim); | |
220 | if (length != 0) | |
221 | cmd->u3.ip = htonl((array[0] << 24) | (array[1] << 16) | |
222 | | (array[2] << 8) | array[3]); | |
223 | } else { | |
224 | /* Now we have IPv6 address. */ | |
225 | length = get_ipv6_addr(data + 3, dlen - 3, | |
226 | (struct in6_addr *)cmd->u3.ip6, delim); | |
227 | } | |
228 | ||
229 | if (length == 0) | |
230 | return 0; | |
231 | pr_debug("EPRT: Got IP address!\n"); | |
232 | /* Start offset includes initial "|1|", and trailing delimiter */ | |
233 | return get_port(data, 3 + length + 1, dlen, delim, &cmd->u.tcp.port); | |
234 | } | |
235 | ||
236 | /* Returns 0, or length of numbers: |||6446| */ | |
237 | static int try_epsv_response(const char *data, size_t dlen, | |
238 | struct nf_conntrack_man *cmd, char term) | |
239 | { | |
240 | char delim; | |
241 | ||
242 | /* Three delimiters. */ | |
243 | if (dlen <= 3) return 0; | |
244 | delim = data[0]; | |
245 | if (isdigit(delim) || delim < 33 || delim > 126 | |
246 | || data[1] != delim || data[2] != delim) | |
247 | return 0; | |
248 | ||
249 | return get_port(data, 3, dlen, delim, &cmd->u.tcp.port); | |
250 | } | |
251 | ||
252 | /* Return 1 for match, 0 for accept, -1 for partial. */ | |
253 | static int find_pattern(const char *data, size_t dlen, | |
254 | const char *pattern, size_t plen, | |
255 | char skip, char term, | |
256 | unsigned int *numoff, | |
257 | unsigned int *numlen, | |
258 | struct nf_conntrack_man *cmd, | |
259 | int (*getnum)(const char *, size_t, | |
260 | struct nf_conntrack_man *, char)) | |
261 | { | |
262 | size_t i; | |
263 | ||
264 | pr_debug("find_pattern `%s': dlen = %Zu\n", pattern, dlen); | |
265 | if (dlen == 0) | |
266 | return 0; | |
267 | ||
268 | if (dlen <= plen) { | |
269 | /* Short packet: try for partial? */ | |
270 | if (strnicmp(data, pattern, dlen) == 0) | |
271 | return -1; | |
272 | else return 0; | |
273 | } | |
274 | ||
275 | if (strnicmp(data, pattern, plen) != 0) { | |
276 | #if 0 | |
277 | size_t i; | |
278 | ||
279 | pr_debug("ftp: string mismatch\n"); | |
280 | for (i = 0; i < plen; i++) { | |
281 | pr_debug("ftp:char %u `%c'(%u) vs `%c'(%u)\n", | |
282 | i, data[i], data[i], | |
283 | pattern[i], pattern[i]); | |
284 | } | |
285 | #endif | |
286 | return 0; | |
287 | } | |
288 | ||
289 | pr_debug("Pattern matches!\n"); | |
290 | /* Now we've found the constant string, try to skip | |
291 | to the 'skip' character */ | |
292 | for (i = plen; data[i] != skip; i++) | |
293 | if (i == dlen - 1) return -1; | |
294 | ||
295 | /* Skip over the last character */ | |
296 | i++; | |
297 | ||
298 | pr_debug("Skipped up to `%c'!\n", skip); | |
299 | ||
300 | *numoff = i; | |
301 | *numlen = getnum(data + i, dlen - i, cmd, term); | |
302 | if (!*numlen) | |
303 | return -1; | |
304 | ||
305 | pr_debug("Match succeeded!\n"); | |
306 | return 1; | |
307 | } | |
308 | ||
309 | /* Look up to see if we're just after a \n. */ | |
310 | static int find_nl_seq(u32 seq, const struct nf_ct_ftp_master *info, int dir) | |
311 | { | |
312 | unsigned int i; | |
313 | ||
314 | for (i = 0; i < info->seq_aft_nl_num[dir]; i++) | |
315 | if (info->seq_aft_nl[dir][i] == seq) | |
316 | return 1; | |
317 | return 0; | |
318 | } | |
319 | ||
320 | /* We don't update if it's older than what we have. */ | |
321 | static void update_nl_seq(u32 nl_seq, struct nf_ct_ftp_master *info, int dir, | |
322 | struct sk_buff *skb) | |
323 | { | |
324 | unsigned int i, oldest = NUM_SEQ_TO_REMEMBER; | |
325 | ||
326 | /* Look for oldest: if we find exact match, we're done. */ | |
327 | for (i = 0; i < info->seq_aft_nl_num[dir]; i++) { | |
328 | if (info->seq_aft_nl[dir][i] == nl_seq) | |
329 | return; | |
330 | ||
331 | if (oldest == info->seq_aft_nl_num[dir] || | |
332 | before(info->seq_aft_nl[dir][i], | |
333 | info->seq_aft_nl[dir][oldest])) | |
334 | oldest = i; | |
335 | } | |
336 | ||
337 | if (info->seq_aft_nl_num[dir] < NUM_SEQ_TO_REMEMBER) { | |
338 | info->seq_aft_nl[dir][info->seq_aft_nl_num[dir]++] = nl_seq; | |
339 | nf_conntrack_event_cache(IPCT_HELPINFO_VOLATILE, skb); | |
340 | } else if (oldest != NUM_SEQ_TO_REMEMBER && | |
341 | after(nl_seq, info->seq_aft_nl[dir][oldest])) { | |
342 | info->seq_aft_nl[dir][oldest] = nl_seq; | |
343 | nf_conntrack_event_cache(IPCT_HELPINFO_VOLATILE, skb); | |
344 | } | |
345 | } | |
346 | ||
347 | static int help(struct sk_buff *skb, | |
348 | unsigned int protoff, | |
349 | struct nf_conn *ct, | |
350 | enum ip_conntrack_info ctinfo) | |
351 | { | |
352 | unsigned int dataoff, datalen; | |
353 | const struct tcphdr *th; | |
354 | struct tcphdr _tcph; | |
355 | const char *fb_ptr; | |
356 | int ret; | |
357 | u32 seq; | |
358 | int dir = CTINFO2DIR(ctinfo); | |
359 | unsigned int matchlen, matchoff; | |
360 | struct nf_ct_ftp_master *ct_ftp_info = &nfct_help(ct)->help.ct_ftp_info; | |
361 | struct nf_conntrack_expect *exp; | |
362 | union nf_inet_addr *daddr; | |
363 | struct nf_conntrack_man cmd = {}; | |
364 | unsigned int i; | |
365 | int found = 0, ends_in_nl; | |
366 | typeof(nf_nat_ftp_hook) nf_nat_ftp; | |
367 | ||
368 | /* Until there's been traffic both ways, don't look in packets. */ | |
369 | if (ctinfo != IP_CT_ESTABLISHED | |
370 | && ctinfo != IP_CT_ESTABLISHED+IP_CT_IS_REPLY) { | |
371 | pr_debug("ftp: Conntrackinfo = %u\n", ctinfo); | |
372 | return NF_ACCEPT; | |
373 | } | |
374 | ||
375 | th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph); | |
376 | if (th == NULL) | |
377 | return NF_ACCEPT; | |
378 | ||
379 | dataoff = protoff + th->doff * 4; | |
380 | /* No data? */ | |
381 | if (dataoff >= skb->len) { | |
382 | pr_debug("ftp: dataoff(%u) >= skblen(%u)\n", dataoff, | |
383 | skb->len); | |
384 | return NF_ACCEPT; | |
385 | } | |
386 | datalen = skb->len - dataoff; | |
387 | ||
388 | spin_lock_bh(&nf_ftp_lock); | |
389 | fb_ptr = skb_header_pointer(skb, dataoff, datalen, ftp_buffer); | |
390 | BUG_ON(fb_ptr == NULL); | |
391 | ||
392 | ends_in_nl = (fb_ptr[datalen - 1] == '\n'); | |
393 | seq = ntohl(th->seq) + datalen; | |
394 | ||
395 | /* Look up to see if we're just after a \n. */ | |
396 | if (!find_nl_seq(ntohl(th->seq), ct_ftp_info, dir)) { | |
397 | /* Now if this ends in \n, update ftp info. */ | |
398 | pr_debug("nf_conntrack_ftp: wrong seq pos %s(%u) or %s(%u)\n", | |
399 | ct_ftp_info->seq_aft_nl_num[dir] > 0 ? "" : "(UNSET)", | |
400 | ct_ftp_info->seq_aft_nl[dir][0], | |
401 | ct_ftp_info->seq_aft_nl_num[dir] > 1 ? "" : "(UNSET)", | |
402 | ct_ftp_info->seq_aft_nl[dir][1]); | |
403 | ret = NF_ACCEPT; | |
404 | goto out_update_nl; | |
405 | } | |
406 | ||
407 | /* Initialize IP/IPv6 addr to expected address (it's not mentioned | |
408 | in EPSV responses) */ | |
409 | cmd.l3num = ct->tuplehash[dir].tuple.src.l3num; | |
410 | memcpy(cmd.u3.all, &ct->tuplehash[dir].tuple.src.u3.all, | |
411 | sizeof(cmd.u3.all)); | |
412 | ||
413 | for (i = 0; i < ARRAY_SIZE(search[dir]); i++) { | |
414 | found = find_pattern(fb_ptr, datalen, | |
415 | search[dir][i].pattern, | |
416 | search[dir][i].plen, | |
417 | search[dir][i].skip, | |
418 | search[dir][i].term, | |
419 | &matchoff, &matchlen, | |
420 | &cmd, | |
421 | search[dir][i].getnum); | |
422 | if (found) break; | |
423 | } | |
424 | if (found == -1) { | |
425 | /* We don't usually drop packets. After all, this is | |
426 | connection tracking, not packet filtering. | |
427 | However, it is necessary for accurate tracking in | |
428 | this case. */ | |
429 | if (net_ratelimit()) | |
430 | printk("conntrack_ftp: partial %s %u+%u\n", | |
431 | search[dir][i].pattern, | |
432 | ntohl(th->seq), datalen); | |
433 | ret = NF_DROP; | |
434 | goto out; | |
435 | } else if (found == 0) { /* No match */ | |
436 | ret = NF_ACCEPT; | |
437 | goto out_update_nl; | |
438 | } | |
439 | ||
440 | pr_debug("conntrack_ftp: match `%.*s' (%u bytes at %u)\n", | |
441 | matchlen, fb_ptr + matchoff, | |
442 | matchlen, ntohl(th->seq) + matchoff); | |
443 | ||
444 | exp = nf_ct_expect_alloc(ct); | |
445 | if (exp == NULL) { | |
446 | ret = NF_DROP; | |
447 | goto out; | |
448 | } | |
449 | ||
450 | /* We refer to the reverse direction ("!dir") tuples here, | |
451 | * because we're expecting something in the other direction. | |
452 | * Doesn't matter unless NAT is happening. */ | |
453 | daddr = &ct->tuplehash[!dir].tuple.dst.u3; | |
454 | ||
455 | /* Update the ftp info */ | |
456 | if ((cmd.l3num == ct->tuplehash[dir].tuple.src.l3num) && | |
457 | memcmp(&cmd.u3.all, &ct->tuplehash[dir].tuple.src.u3.all, | |
458 | sizeof(cmd.u3.all))) { | |
459 | /* Enrico Scholz's passive FTP to partially RNAT'd ftp | |
460 | server: it really wants us to connect to a | |
461 | different IP address. Simply don't record it for | |
462 | NAT. */ | |
463 | if (cmd.l3num == PF_INET) { | |
464 | pr_debug("conntrack_ftp: NOT RECORDING: " NIPQUAD_FMT | |
465 | " != " NIPQUAD_FMT "\n", | |
466 | NIPQUAD(cmd.u3.ip), | |
467 | NIPQUAD(ct->tuplehash[dir].tuple.src.u3.ip)); | |
468 | } else { | |
469 | pr_debug("conntrack_ftp: NOT RECORDING: " NIP6_FMT | |
470 | " != " NIP6_FMT "\n", | |
471 | NIP6(*((struct in6_addr *)cmd.u3.ip6)), | |
472 | NIP6(*((struct in6_addr *) | |
473 | ct->tuplehash[dir].tuple.src.u3.ip6))); | |
474 | } | |
475 | ||
476 | /* Thanks to Cristiano Lincoln Mattos | |
477 | <lincoln@cesar.org.br> for reporting this potential | |
478 | problem (DMZ machines opening holes to internal | |
479 | networks, or the packet filter itself). */ | |
480 | if (!loose) { | |
481 | ret = NF_ACCEPT; | |
482 | goto out_put_expect; | |
483 | } | |
484 | daddr = &cmd.u3; | |
485 | } | |
486 | ||
487 | nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, cmd.l3num, | |
488 | &ct->tuplehash[!dir].tuple.src.u3, daddr, | |
489 | IPPROTO_TCP, NULL, &cmd.u.tcp.port); | |
490 | ||
491 | /* Now, NAT might want to mangle the packet, and register the | |
492 | * (possibly changed) expectation itself. */ | |
493 | nf_nat_ftp = rcu_dereference(nf_nat_ftp_hook); | |
494 | if (nf_nat_ftp && ct->status & IPS_NAT_MASK) | |
495 | ret = nf_nat_ftp(skb, ctinfo, search[dir][i].ftptype, | |
496 | matchoff, matchlen, exp); | |
497 | else { | |
498 | /* Can't expect this? Best to drop packet now. */ | |
499 | if (nf_ct_expect_related(exp) != 0) | |
500 | ret = NF_DROP; | |
501 | else | |
502 | ret = NF_ACCEPT; | |
503 | } | |
504 | ||
505 | out_put_expect: | |
506 | nf_ct_expect_put(exp); | |
507 | ||
508 | out_update_nl: | |
509 | /* Now if this ends in \n, update ftp info. Seq may have been | |
510 | * adjusted by NAT code. */ | |
511 | if (ends_in_nl) | |
512 | update_nl_seq(seq, ct_ftp_info, dir, skb); | |
513 | out: | |
514 | spin_unlock_bh(&nf_ftp_lock); | |
515 | return ret; | |
516 | } | |
517 | ||
518 | static struct nf_conntrack_helper ftp[MAX_PORTS][2] __read_mostly; | |
519 | static char ftp_names[MAX_PORTS][2][sizeof("ftp-65535")] __read_mostly; | |
520 | ||
521 | static const struct nf_conntrack_expect_policy ftp_exp_policy = { | |
522 | .max_expected = 1, | |
523 | .timeout = 5 * 60, | |
524 | }; | |
525 | ||
526 | /* don't make this __exit, since it's called from __init ! */ | |
527 | static void nf_conntrack_ftp_fini(void) | |
528 | { | |
529 | int i, j; | |
530 | for (i = 0; i < ports_c; i++) { | |
531 | for (j = 0; j < 2; j++) { | |
532 | if (ftp[i][j].me == NULL) | |
533 | continue; | |
534 | ||
535 | pr_debug("nf_ct_ftp: unregistering helper for pf: %d " | |
536 | "port: %d\n", | |
537 | ftp[i][j].tuple.src.l3num, ports[i]); | |
538 | nf_conntrack_helper_unregister(&ftp[i][j]); | |
539 | } | |
540 | } | |
541 | ||
542 | kfree(ftp_buffer); | |
543 | } | |
544 | ||
545 | static int __init nf_conntrack_ftp_init(void) | |
546 | { | |
547 | int i, j = -1, ret = 0; | |
548 | char *tmpname; | |
549 | ||
550 | ftp_buffer = kmalloc(65536, GFP_KERNEL); | |
551 | if (!ftp_buffer) | |
552 | return -ENOMEM; | |
553 | ||
554 | if (ports_c == 0) | |
555 | ports[ports_c++] = FTP_PORT; | |
556 | ||
557 | /* FIXME should be configurable whether IPv4 and IPv6 FTP connections | |
558 | are tracked or not - YK */ | |
559 | for (i = 0; i < ports_c; i++) { | |
560 | ftp[i][0].tuple.src.l3num = PF_INET; | |
561 | ftp[i][1].tuple.src.l3num = PF_INET6; | |
562 | for (j = 0; j < 2; j++) { | |
563 | ftp[i][j].tuple.src.u.tcp.port = htons(ports[i]); | |
564 | ftp[i][j].tuple.dst.protonum = IPPROTO_TCP; | |
565 | ftp[i][j].expect_policy = &ftp_exp_policy; | |
566 | ftp[i][j].me = THIS_MODULE; | |
567 | ftp[i][j].help = help; | |
568 | tmpname = &ftp_names[i][j][0]; | |
569 | if (ports[i] == FTP_PORT) | |
570 | sprintf(tmpname, "ftp"); | |
571 | else | |
572 | sprintf(tmpname, "ftp-%d", ports[i]); | |
573 | ftp[i][j].name = tmpname; | |
574 | ||
575 | pr_debug("nf_ct_ftp: registering helper for pf: %d " | |
576 | "port: %d\n", | |
577 | ftp[i][j].tuple.src.l3num, ports[i]); | |
578 | ret = nf_conntrack_helper_register(&ftp[i][j]); | |
579 | if (ret) { | |
580 | printk("nf_ct_ftp: failed to register helper " | |
581 | " for pf: %d port: %d\n", | |
582 | ftp[i][j].tuple.src.l3num, ports[i]); | |
583 | nf_conntrack_ftp_fini(); | |
584 | return ret; | |
585 | } | |
586 | } | |
587 | } | |
588 | ||
589 | return 0; | |
590 | } | |
591 | ||
592 | module_init(nf_conntrack_ftp_init); | |
593 | module_exit(nf_conntrack_ftp_fini); |