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1da177e4 LT |
1 | /* |
2 | * ip_vs_app.c: Application module support for IPVS | |
3 | * | |
1da177e4 LT |
4 | * Authors: Wensong Zhang <wensong@linuxvirtualserver.org> |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | * | |
11 | * Most code here is taken from ip_masq_app.c in kernel 2.2. The difference | |
12 | * is that ip_vs_app module handles the reverse direction (incoming requests | |
13 | * and outgoing responses). | |
14 | * | |
15 | * IP_MASQ_APP application masquerading module | |
16 | * | |
17 | * Author: Juan Jose Ciarlante, <jjciarla@raiz.uncu.edu.ar> | |
18 | * | |
19 | */ | |
20 | ||
9aada7ac HE |
21 | #define KMSG_COMPONENT "IPVS" |
22 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt | |
23 | ||
1da177e4 LT |
24 | #include <linux/module.h> |
25 | #include <linux/kernel.h> | |
26 | #include <linux/skbuff.h> | |
27 | #include <linux/in.h> | |
28 | #include <linux/ip.h> | |
af1e1cf0 | 29 | #include <linux/netfilter.h> |
5a0e3ad6 | 30 | #include <linux/slab.h> |
457c4cbc | 31 | #include <net/net_namespace.h> |
1da177e4 | 32 | #include <net/protocol.h> |
c752f073 | 33 | #include <net/tcp.h> |
1da177e4 LT |
34 | #include <asm/system.h> |
35 | #include <linux/stat.h> | |
36 | #include <linux/proc_fs.h> | |
37 | #include <linux/seq_file.h> | |
57b47a53 | 38 | #include <linux/mutex.h> |
1da177e4 LT |
39 | |
40 | #include <net/ip_vs.h> | |
41 | ||
42 | EXPORT_SYMBOL(register_ip_vs_app); | |
43 | EXPORT_SYMBOL(unregister_ip_vs_app); | |
44 | EXPORT_SYMBOL(register_ip_vs_app_inc); | |
45 | ||
46 | /* ipvs application list head */ | |
47 | static LIST_HEAD(ip_vs_app_list); | |
57b47a53 | 48 | static DEFINE_MUTEX(__ip_vs_app_mutex); |
1da177e4 LT |
49 | |
50 | ||
51 | /* | |
52 | * Get an ip_vs_app object | |
53 | */ | |
54 | static inline int ip_vs_app_get(struct ip_vs_app *app) | |
55 | { | |
85b60680 | 56 | return try_module_get(app->module); |
1da177e4 LT |
57 | } |
58 | ||
59 | ||
60 | static inline void ip_vs_app_put(struct ip_vs_app *app) | |
61 | { | |
85b60680 | 62 | module_put(app->module); |
1da177e4 LT |
63 | } |
64 | ||
65 | ||
66 | /* | |
67 | * Allocate/initialize app incarnation and register it in proto apps. | |
68 | */ | |
69 | static int | |
70 | ip_vs_app_inc_new(struct ip_vs_app *app, __u16 proto, __u16 port) | |
71 | { | |
72 | struct ip_vs_protocol *pp; | |
73 | struct ip_vs_app *inc; | |
74 | int ret; | |
75 | ||
76 | if (!(pp = ip_vs_proto_get(proto))) | |
77 | return -EPROTONOSUPPORT; | |
78 | ||
79 | if (!pp->unregister_app) | |
80 | return -EOPNOTSUPP; | |
81 | ||
8b2ed4bb | 82 | inc = kmemdup(app, sizeof(*inc), GFP_KERNEL); |
1da177e4 LT |
83 | if (!inc) |
84 | return -ENOMEM; | |
1da177e4 LT |
85 | INIT_LIST_HEAD(&inc->p_list); |
86 | INIT_LIST_HEAD(&inc->incs_list); | |
87 | inc->app = app; | |
88 | inc->port = htons(port); | |
89 | atomic_set(&inc->usecnt, 0); | |
90 | ||
91 | if (app->timeouts) { | |
92 | inc->timeout_table = | |
93 | ip_vs_create_timeout_table(app->timeouts, | |
94 | app->timeouts_size); | |
95 | if (!inc->timeout_table) { | |
96 | ret = -ENOMEM; | |
97 | goto out; | |
98 | } | |
99 | } | |
100 | ||
101 | ret = pp->register_app(inc); | |
102 | if (ret) | |
103 | goto out; | |
104 | ||
105 | list_add(&inc->a_list, &app->incs_list); | |
106 | IP_VS_DBG(9, "%s application %s:%u registered\n", | |
107 | pp->name, inc->name, inc->port); | |
108 | ||
109 | return 0; | |
110 | ||
111 | out: | |
a51482bd | 112 | kfree(inc->timeout_table); |
1da177e4 LT |
113 | kfree(inc); |
114 | return ret; | |
115 | } | |
116 | ||
117 | ||
118 | /* | |
119 | * Release app incarnation | |
120 | */ | |
121 | static void | |
122 | ip_vs_app_inc_release(struct ip_vs_app *inc) | |
123 | { | |
124 | struct ip_vs_protocol *pp; | |
125 | ||
126 | if (!(pp = ip_vs_proto_get(inc->protocol))) | |
127 | return; | |
128 | ||
129 | if (pp->unregister_app) | |
130 | pp->unregister_app(inc); | |
131 | ||
132 | IP_VS_DBG(9, "%s App %s:%u unregistered\n", | |
133 | pp->name, inc->name, inc->port); | |
134 | ||
135 | list_del(&inc->a_list); | |
136 | ||
a51482bd | 137 | kfree(inc->timeout_table); |
1da177e4 LT |
138 | kfree(inc); |
139 | } | |
140 | ||
141 | ||
142 | /* | |
143 | * Get reference to app inc (only called from softirq) | |
144 | * | |
145 | */ | |
146 | int ip_vs_app_inc_get(struct ip_vs_app *inc) | |
147 | { | |
148 | int result; | |
149 | ||
150 | atomic_inc(&inc->usecnt); | |
151 | if (unlikely((result = ip_vs_app_get(inc->app)) != 1)) | |
152 | atomic_dec(&inc->usecnt); | |
153 | return result; | |
154 | } | |
155 | ||
156 | ||
157 | /* | |
158 | * Put the app inc (only called from timer or net softirq) | |
159 | */ | |
160 | void ip_vs_app_inc_put(struct ip_vs_app *inc) | |
161 | { | |
162 | ip_vs_app_put(inc->app); | |
163 | atomic_dec(&inc->usecnt); | |
164 | } | |
165 | ||
166 | ||
167 | /* | |
168 | * Register an application incarnation in protocol applications | |
169 | */ | |
170 | int | |
171 | register_ip_vs_app_inc(struct ip_vs_app *app, __u16 proto, __u16 port) | |
172 | { | |
173 | int result; | |
174 | ||
57b47a53 | 175 | mutex_lock(&__ip_vs_app_mutex); |
1da177e4 LT |
176 | |
177 | result = ip_vs_app_inc_new(app, proto, port); | |
178 | ||
57b47a53 | 179 | mutex_unlock(&__ip_vs_app_mutex); |
1da177e4 LT |
180 | |
181 | return result; | |
182 | } | |
183 | ||
184 | ||
185 | /* | |
186 | * ip_vs_app registration routine | |
187 | */ | |
188 | int register_ip_vs_app(struct ip_vs_app *app) | |
189 | { | |
190 | /* increase the module use count */ | |
191 | ip_vs_use_count_inc(); | |
192 | ||
57b47a53 | 193 | mutex_lock(&__ip_vs_app_mutex); |
1da177e4 LT |
194 | |
195 | list_add(&app->a_list, &ip_vs_app_list); | |
196 | ||
57b47a53 | 197 | mutex_unlock(&__ip_vs_app_mutex); |
1da177e4 LT |
198 | |
199 | return 0; | |
200 | } | |
201 | ||
202 | ||
203 | /* | |
204 | * ip_vs_app unregistration routine | |
205 | * We are sure there are no app incarnations attached to services | |
206 | */ | |
207 | void unregister_ip_vs_app(struct ip_vs_app *app) | |
208 | { | |
209 | struct ip_vs_app *inc, *nxt; | |
210 | ||
57b47a53 | 211 | mutex_lock(&__ip_vs_app_mutex); |
1da177e4 LT |
212 | |
213 | list_for_each_entry_safe(inc, nxt, &app->incs_list, a_list) { | |
214 | ip_vs_app_inc_release(inc); | |
215 | } | |
216 | ||
217 | list_del(&app->a_list); | |
218 | ||
57b47a53 | 219 | mutex_unlock(&__ip_vs_app_mutex); |
1da177e4 LT |
220 | |
221 | /* decrease the module use count */ | |
222 | ip_vs_use_count_dec(); | |
223 | } | |
224 | ||
225 | ||
1da177e4 LT |
226 | /* |
227 | * Bind ip_vs_conn to its ip_vs_app (called by cp constructor) | |
228 | */ | |
229 | int ip_vs_bind_app(struct ip_vs_conn *cp, struct ip_vs_protocol *pp) | |
230 | { | |
231 | return pp->app_conn_bind(cp); | |
232 | } | |
233 | ||
234 | ||
235 | /* | |
236 | * Unbind cp from application incarnation (called by cp destructor) | |
237 | */ | |
238 | void ip_vs_unbind_app(struct ip_vs_conn *cp) | |
239 | { | |
240 | struct ip_vs_app *inc = cp->app; | |
241 | ||
242 | if (!inc) | |
243 | return; | |
244 | ||
245 | if (inc->unbind_conn) | |
246 | inc->unbind_conn(inc, cp); | |
247 | if (inc->done_conn) | |
248 | inc->done_conn(inc, cp); | |
249 | ip_vs_app_inc_put(inc); | |
250 | cp->app = NULL; | |
251 | } | |
252 | ||
253 | ||
254 | /* | |
255 | * Fixes th->seq based on ip_vs_seq info. | |
256 | */ | |
257 | static inline void vs_fix_seq(const struct ip_vs_seq *vseq, struct tcphdr *th) | |
258 | { | |
259 | __u32 seq = ntohl(th->seq); | |
260 | ||
261 | /* | |
262 | * Adjust seq with delta-offset for all packets after | |
263 | * the most recent resized pkt seq and with previous_delta offset | |
264 | * for all packets before most recent resized pkt seq. | |
265 | */ | |
266 | if (vseq->delta || vseq->previous_delta) { | |
267 | if(after(seq, vseq->init_seq)) { | |
268 | th->seq = htonl(seq + vseq->delta); | |
1e3e238e HE |
269 | IP_VS_DBG(9, "%s(): added delta (%d) to seq\n", |
270 | __func__, vseq->delta); | |
1da177e4 LT |
271 | } else { |
272 | th->seq = htonl(seq + vseq->previous_delta); | |
1e3e238e HE |
273 | IP_VS_DBG(9, "%s(): added previous_delta (%d) to seq\n", |
274 | __func__, vseq->previous_delta); | |
1da177e4 LT |
275 | } |
276 | } | |
277 | } | |
278 | ||
279 | ||
280 | /* | |
281 | * Fixes th->ack_seq based on ip_vs_seq info. | |
282 | */ | |
283 | static inline void | |
284 | vs_fix_ack_seq(const struct ip_vs_seq *vseq, struct tcphdr *th) | |
285 | { | |
286 | __u32 ack_seq = ntohl(th->ack_seq); | |
287 | ||
288 | /* | |
289 | * Adjust ack_seq with delta-offset for | |
290 | * the packets AFTER most recent resized pkt has caused a shift | |
291 | * for packets before most recent resized pkt, use previous_delta | |
292 | */ | |
293 | if (vseq->delta || vseq->previous_delta) { | |
294 | /* since ack_seq is the number of octet that is expected | |
295 | to receive next, so compare it with init_seq+delta */ | |
296 | if(after(ack_seq, vseq->init_seq+vseq->delta)) { | |
297 | th->ack_seq = htonl(ack_seq - vseq->delta); | |
1e3e238e HE |
298 | IP_VS_DBG(9, "%s(): subtracted delta " |
299 | "(%d) from ack_seq\n", __func__, vseq->delta); | |
1da177e4 LT |
300 | |
301 | } else { | |
302 | th->ack_seq = htonl(ack_seq - vseq->previous_delta); | |
1e3e238e | 303 | IP_VS_DBG(9, "%s(): subtracted " |
1da177e4 | 304 | "previous_delta (%d) from ack_seq\n", |
1e3e238e | 305 | __func__, vseq->previous_delta); |
1da177e4 LT |
306 | } |
307 | } | |
308 | } | |
309 | ||
310 | ||
311 | /* | |
312 | * Updates ip_vs_seq if pkt has been resized | |
313 | * Assumes already checked proto==IPPROTO_TCP and diff!=0. | |
314 | */ | |
315 | static inline void vs_seq_update(struct ip_vs_conn *cp, struct ip_vs_seq *vseq, | |
316 | unsigned flag, __u32 seq, int diff) | |
317 | { | |
318 | /* spinlock is to keep updating cp->flags atomic */ | |
319 | spin_lock(&cp->lock); | |
320 | if (!(cp->flags & flag) || after(seq, vseq->init_seq)) { | |
321 | vseq->previous_delta = vseq->delta; | |
322 | vseq->delta += diff; | |
323 | vseq->init_seq = seq; | |
324 | cp->flags |= flag; | |
325 | } | |
326 | spin_unlock(&cp->lock); | |
327 | } | |
328 | ||
3db05fea | 329 | static inline int app_tcp_pkt_out(struct ip_vs_conn *cp, struct sk_buff *skb, |
1da177e4 LT |
330 | struct ip_vs_app *app) |
331 | { | |
332 | int diff; | |
3db05fea | 333 | const unsigned int tcp_offset = ip_hdrlen(skb); |
1da177e4 LT |
334 | struct tcphdr *th; |
335 | __u32 seq; | |
336 | ||
3db05fea | 337 | if (!skb_make_writable(skb, tcp_offset + sizeof(*th))) |
1da177e4 LT |
338 | return 0; |
339 | ||
3db05fea | 340 | th = (struct tcphdr *)(skb_network_header(skb) + tcp_offset); |
1da177e4 LT |
341 | |
342 | /* | |
343 | * Remember seq number in case this pkt gets resized | |
344 | */ | |
345 | seq = ntohl(th->seq); | |
346 | ||
347 | /* | |
348 | * Fix seq stuff if flagged as so. | |
349 | */ | |
350 | if (cp->flags & IP_VS_CONN_F_OUT_SEQ) | |
351 | vs_fix_seq(&cp->out_seq, th); | |
352 | if (cp->flags & IP_VS_CONN_F_IN_SEQ) | |
353 | vs_fix_ack_seq(&cp->in_seq, th); | |
354 | ||
355 | /* | |
356 | * Call private output hook function | |
357 | */ | |
358 | if (app->pkt_out == NULL) | |
359 | return 1; | |
360 | ||
3db05fea | 361 | if (!app->pkt_out(app, cp, skb, &diff)) |
1da177e4 LT |
362 | return 0; |
363 | ||
364 | /* | |
365 | * Update ip_vs seq stuff if len has changed. | |
366 | */ | |
367 | if (diff != 0) | |
368 | vs_seq_update(cp, &cp->out_seq, | |
369 | IP_VS_CONN_F_OUT_SEQ, seq, diff); | |
370 | ||
371 | return 1; | |
372 | } | |
373 | ||
374 | /* | |
375 | * Output pkt hook. Will call bound ip_vs_app specific function | |
376 | * called by ipvs packet handler, assumes previously checked cp!=NULL | |
377 | * returns false if it can't handle packet (oom) | |
378 | */ | |
3db05fea | 379 | int ip_vs_app_pkt_out(struct ip_vs_conn *cp, struct sk_buff *skb) |
1da177e4 LT |
380 | { |
381 | struct ip_vs_app *app; | |
382 | ||
383 | /* | |
384 | * check if application module is bound to | |
385 | * this ip_vs_conn. | |
386 | */ | |
387 | if ((app = cp->app) == NULL) | |
388 | return 1; | |
389 | ||
390 | /* TCP is complicated */ | |
391 | if (cp->protocol == IPPROTO_TCP) | |
3db05fea | 392 | return app_tcp_pkt_out(cp, skb, app); |
1da177e4 LT |
393 | |
394 | /* | |
395 | * Call private output hook function | |
396 | */ | |
397 | if (app->pkt_out == NULL) | |
398 | return 1; | |
399 | ||
3db05fea | 400 | return app->pkt_out(app, cp, skb, NULL); |
1da177e4 LT |
401 | } |
402 | ||
403 | ||
3db05fea | 404 | static inline int app_tcp_pkt_in(struct ip_vs_conn *cp, struct sk_buff *skb, |
1da177e4 LT |
405 | struct ip_vs_app *app) |
406 | { | |
407 | int diff; | |
3db05fea | 408 | const unsigned int tcp_offset = ip_hdrlen(skb); |
1da177e4 LT |
409 | struct tcphdr *th; |
410 | __u32 seq; | |
411 | ||
3db05fea | 412 | if (!skb_make_writable(skb, tcp_offset + sizeof(*th))) |
1da177e4 LT |
413 | return 0; |
414 | ||
3db05fea | 415 | th = (struct tcphdr *)(skb_network_header(skb) + tcp_offset); |
1da177e4 LT |
416 | |
417 | /* | |
418 | * Remember seq number in case this pkt gets resized | |
419 | */ | |
420 | seq = ntohl(th->seq); | |
421 | ||
422 | /* | |
423 | * Fix seq stuff if flagged as so. | |
424 | */ | |
425 | if (cp->flags & IP_VS_CONN_F_IN_SEQ) | |
426 | vs_fix_seq(&cp->in_seq, th); | |
427 | if (cp->flags & IP_VS_CONN_F_OUT_SEQ) | |
428 | vs_fix_ack_seq(&cp->out_seq, th); | |
429 | ||
430 | /* | |
431 | * Call private input hook function | |
432 | */ | |
433 | if (app->pkt_in == NULL) | |
434 | return 1; | |
435 | ||
3db05fea | 436 | if (!app->pkt_in(app, cp, skb, &diff)) |
1da177e4 LT |
437 | return 0; |
438 | ||
439 | /* | |
440 | * Update ip_vs seq stuff if len has changed. | |
441 | */ | |
442 | if (diff != 0) | |
443 | vs_seq_update(cp, &cp->in_seq, | |
444 | IP_VS_CONN_F_IN_SEQ, seq, diff); | |
445 | ||
446 | return 1; | |
447 | } | |
448 | ||
449 | /* | |
450 | * Input pkt hook. Will call bound ip_vs_app specific function | |
451 | * called by ipvs packet handler, assumes previously checked cp!=NULL. | |
452 | * returns false if can't handle packet (oom). | |
453 | */ | |
3db05fea | 454 | int ip_vs_app_pkt_in(struct ip_vs_conn *cp, struct sk_buff *skb) |
1da177e4 LT |
455 | { |
456 | struct ip_vs_app *app; | |
457 | ||
458 | /* | |
459 | * check if application module is bound to | |
460 | * this ip_vs_conn. | |
461 | */ | |
462 | if ((app = cp->app) == NULL) | |
463 | return 1; | |
464 | ||
465 | /* TCP is complicated */ | |
466 | if (cp->protocol == IPPROTO_TCP) | |
3db05fea | 467 | return app_tcp_pkt_in(cp, skb, app); |
1da177e4 LT |
468 | |
469 | /* | |
470 | * Call private input hook function | |
471 | */ | |
472 | if (app->pkt_in == NULL) | |
473 | return 1; | |
474 | ||
3db05fea | 475 | return app->pkt_in(app, cp, skb, NULL); |
1da177e4 LT |
476 | } |
477 | ||
478 | ||
479 | #ifdef CONFIG_PROC_FS | |
480 | /* | |
481 | * /proc/net/ip_vs_app entry function | |
482 | */ | |
483 | ||
484 | static struct ip_vs_app *ip_vs_app_idx(loff_t pos) | |
485 | { | |
486 | struct ip_vs_app *app, *inc; | |
487 | ||
488 | list_for_each_entry(app, &ip_vs_app_list, a_list) { | |
489 | list_for_each_entry(inc, &app->incs_list, a_list) { | |
490 | if (pos-- == 0) | |
491 | return inc; | |
492 | } | |
493 | } | |
494 | return NULL; | |
495 | ||
496 | } | |
497 | ||
498 | static void *ip_vs_app_seq_start(struct seq_file *seq, loff_t *pos) | |
499 | { | |
57b47a53 | 500 | mutex_lock(&__ip_vs_app_mutex); |
1da177e4 LT |
501 | |
502 | return *pos ? ip_vs_app_idx(*pos - 1) : SEQ_START_TOKEN; | |
503 | } | |
504 | ||
505 | static void *ip_vs_app_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
506 | { | |
507 | struct ip_vs_app *inc, *app; | |
508 | struct list_head *e; | |
509 | ||
510 | ++*pos; | |
511 | if (v == SEQ_START_TOKEN) | |
512 | return ip_vs_app_idx(0); | |
513 | ||
514 | inc = v; | |
515 | app = inc->app; | |
516 | ||
517 | if ((e = inc->a_list.next) != &app->incs_list) | |
518 | return list_entry(e, struct ip_vs_app, a_list); | |
519 | ||
520 | /* go on to next application */ | |
521 | for (e = app->a_list.next; e != &ip_vs_app_list; e = e->next) { | |
522 | app = list_entry(e, struct ip_vs_app, a_list); | |
523 | list_for_each_entry(inc, &app->incs_list, a_list) { | |
524 | return inc; | |
525 | } | |
526 | } | |
527 | return NULL; | |
528 | } | |
529 | ||
530 | static void ip_vs_app_seq_stop(struct seq_file *seq, void *v) | |
531 | { | |
57b47a53 | 532 | mutex_unlock(&__ip_vs_app_mutex); |
1da177e4 LT |
533 | } |
534 | ||
535 | static int ip_vs_app_seq_show(struct seq_file *seq, void *v) | |
536 | { | |
537 | if (v == SEQ_START_TOKEN) | |
538 | seq_puts(seq, "prot port usecnt name\n"); | |
539 | else { | |
540 | const struct ip_vs_app *inc = v; | |
541 | ||
542 | seq_printf(seq, "%-3s %-7u %-6d %-17s\n", | |
543 | ip_vs_proto_name(inc->protocol), | |
544 | ntohs(inc->port), | |
545 | atomic_read(&inc->usecnt), | |
546 | inc->name); | |
547 | } | |
548 | return 0; | |
549 | } | |
550 | ||
56b3d975 | 551 | static const struct seq_operations ip_vs_app_seq_ops = { |
1da177e4 LT |
552 | .start = ip_vs_app_seq_start, |
553 | .next = ip_vs_app_seq_next, | |
554 | .stop = ip_vs_app_seq_stop, | |
555 | .show = ip_vs_app_seq_show, | |
556 | }; | |
557 | ||
558 | static int ip_vs_app_open(struct inode *inode, struct file *file) | |
559 | { | |
560 | return seq_open(file, &ip_vs_app_seq_ops); | |
561 | } | |
562 | ||
9a32144e | 563 | static const struct file_operations ip_vs_app_fops = { |
1da177e4 LT |
564 | .owner = THIS_MODULE, |
565 | .open = ip_vs_app_open, | |
566 | .read = seq_read, | |
567 | .llseek = seq_lseek, | |
568 | .release = seq_release, | |
569 | }; | |
570 | #endif | |
571 | ||
572 | ||
573 | /* | |
574 | * Replace a segment of data with a new segment | |
575 | */ | |
dd0fc66f | 576 | int ip_vs_skb_replace(struct sk_buff *skb, gfp_t pri, |
1da177e4 LT |
577 | char *o_buf, int o_len, char *n_buf, int n_len) |
578 | { | |
1da177e4 LT |
579 | int diff; |
580 | int o_offset; | |
581 | int o_left; | |
582 | ||
583 | EnterFunction(9); | |
584 | ||
585 | diff = n_len - o_len; | |
586 | o_offset = o_buf - (char *)skb->data; | |
587 | /* The length of left data after o_buf+o_len in the skb data */ | |
588 | o_left = skb->len - (o_offset + o_len); | |
589 | ||
590 | if (diff <= 0) { | |
591 | memmove(o_buf + n_len, o_buf + o_len, o_left); | |
592 | memcpy(o_buf, n_buf, n_len); | |
593 | skb_trim(skb, skb->len + diff); | |
594 | } else if (diff <= skb_tailroom(skb)) { | |
595 | skb_put(skb, diff); | |
596 | memmove(o_buf + n_len, o_buf + o_len, o_left); | |
597 | memcpy(o_buf, n_buf, n_len); | |
598 | } else { | |
599 | if (pskb_expand_head(skb, skb_headroom(skb), diff, pri)) | |
600 | return -ENOMEM; | |
601 | skb_put(skb, diff); | |
602 | memmove(skb->data + o_offset + n_len, | |
603 | skb->data + o_offset + o_len, o_left); | |
27d7ff46 | 604 | skb_copy_to_linear_data_offset(skb, o_offset, n_buf, n_len); |
1da177e4 LT |
605 | } |
606 | ||
607 | /* must update the iph total length here */ | |
eddc9ec5 | 608 | ip_hdr(skb)->tot_len = htons(skb->len); |
1da177e4 LT |
609 | |
610 | LeaveFunction(9); | |
611 | return 0; | |
612 | } | |
613 | ||
614 | ||
048cf48b | 615 | int __init ip_vs_app_init(void) |
1da177e4 LT |
616 | { |
617 | /* we will replace it with proc_net_ipvs_create() soon */ | |
457c4cbc | 618 | proc_net_fops_create(&init_net, "ip_vs_app", 0, &ip_vs_app_fops); |
1da177e4 LT |
619 | return 0; |
620 | } | |
621 | ||
622 | ||
623 | void ip_vs_app_cleanup(void) | |
624 | { | |
457c4cbc | 625 | proc_net_remove(&init_net, "ip_vs_app"); |
1da177e4 | 626 | } |