1 /*-
2 * Copyright (c) 2006 Alexander Motin <mav@alkar.net>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice unmodified, this list of conditions, and the following
10 * disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * $FreeBSD: src/sys/netgraph/ng_deflate.c,v 1.3 2007/01/15 05:55:56 glebius Exp $
28 */
29
30 /*
31 * Deflate PPP compression netgraph node type.
32 */
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/mbuf.h>
38 #include <sys/malloc.h>
39 #include <sys/errno.h>
40 #include <sys/syslog.h>
41
42 #include <net/zlib.h>
43
44 #include <netgraph7/ng_message.h>
45 #include <netgraph7/netgraph.h>
46 #include <netgraph7/ng_parse.h>
47 #include "ng_deflate.h"
48
49 #include "opt_netgraph.h"
50
51 MALLOC_DEFINE(M_NETGRAPH_DEFLATE, "netgraph_deflate", "netgraph deflate node ");
52
53 /* DEFLATE header length */
54 #define DEFLATE_HDRLEN 2
55
56 #define PROT_COMPD 0x00fd
57
58 #define DEFLATE_BUF_SIZE 4096
59
60 /* Node private data */
61 struct ng_deflate_private {
62 struct ng_deflate_config cfg; /* configuration */
63 u_char inbuf[DEFLATE_BUF_SIZE]; /* input buffer */
64 u_char outbuf[DEFLATE_BUF_SIZE]; /* output buffer */
65 z_stream cx; /* compression context */
66 struct ng_deflate_stats stats; /* statistics */
67 ng_ID_t ctrlnode; /* path to controlling node */
68 uint16_t seqnum; /* sequence number */
69 u_char compress; /* compress/decompress flag */
70 };
71 typedef struct ng_deflate_private *priv_p;
72
73 /* Netgraph node methods */
74 static ng_constructor_t ng_deflate_constructor;
75 static ng_rcvmsg_t ng_deflate_rcvmsg;
76 static ng_shutdown_t ng_deflate_shutdown;
77 static ng_newhook_t ng_deflate_newhook;
78 static ng_rcvdata_t ng_deflate_rcvdata;
79 static ng_disconnect_t ng_deflate_disconnect;
80
81 /* Helper functions */
82 static void *z_alloc(void *, u_int items, u_int size);
83 static void z_free(void *, void *ptr);
84 static int ng_deflate_compress(node_p node,
85 struct mbuf *m, struct mbuf **resultp);
86 static int ng_deflate_decompress(node_p node,
87 struct mbuf *m, struct mbuf **resultp);
88 static void ng_deflate_reset_req(node_p node);
89
90 /* Parse type for struct ng_deflate_config. */
91 static const struct ng_parse_struct_field ng_deflate_config_type_fields[]
92 = NG_DEFLATE_CONFIG_INFO;
93 static const struct ng_parse_type ng_deflate_config_type = {
94 &ng_parse_struct_type,
95 ng_deflate_config_type_fields
96 };
97
98 /* Parse type for struct ng_deflate_stat. */
99 static const struct ng_parse_struct_field ng_deflate_stats_type_fields[]
100 = NG_DEFLATE_STATS_INFO;
101 static const struct ng_parse_type ng_deflate_stat_type = {
102 &ng_parse_struct_type,
103 ng_deflate_stats_type_fields
104 };
105
106 /* List of commands and how to convert arguments to/from ASCII. */
107 static const struct ng_cmdlist ng_deflate_cmds[] = {
108 {
109 NGM_DEFLATE_COOKIE,
110 NGM_DEFLATE_CONFIG,
111 "config",
112 &ng_deflate_config_type,
113 NULL
114 },
115 {
116 NGM_DEFLATE_COOKIE,
117 NGM_DEFLATE_RESETREQ,
118 "resetreq",
119 NULL,
120 NULL
121 },
122 {
123 NGM_DEFLATE_COOKIE,
124 NGM_DEFLATE_GET_STATS,
125 "getstats",
126 NULL,
127 &ng_deflate_stat_type
128 },
129 {
130 NGM_DEFLATE_COOKIE,
131 NGM_DEFLATE_CLR_STATS,
132 "clrstats",
133 NULL,
134 NULL
135 },
136 {
137 NGM_DEFLATE_COOKIE,
138 NGM_DEFLATE_GETCLR_STATS,
139 "getclrstats",
140 NULL,
141 &ng_deflate_stat_type
142 },
143 { 0 }
144 };
145
146 /* Node type descriptor */
147 static struct ng_type ng_deflate_typestruct = {
148 .version = NG_ABI_VERSION,
149 .name = NG_DEFLATE_NODE_TYPE,
150 .constructor = ng_deflate_constructor,
151 .rcvmsg = ng_deflate_rcvmsg,
152 .shutdown = ng_deflate_shutdown,
153 .newhook = ng_deflate_newhook,
154 .rcvdata = ng_deflate_rcvdata,
155 .disconnect = ng_deflate_disconnect,
156 .cmdlist = ng_deflate_cmds,
157 };
158 NETGRAPH_INIT(deflate, &ng_deflate_typestruct);
159
160 /* Depend on separate zlib module. */
161 MODULE_DEPEND(ng_deflate, zlib, 1, 1, 1);
162
163 #define ERROUT(x) do { error = (x); goto done; } while (0)
164
165 /************************************************************************
166 NETGRAPH NODE STUFF
167 ************************************************************************/
168
169 /*
170 * Node type constructor
171 */
172 static int
ng_deflate_constructor(node_p node)173 ng_deflate_constructor(node_p node)
174 {
175 priv_p priv;
176
177 /* Allocate private structure. */
178 priv = kmalloc(sizeof(*priv), M_NETGRAPH_DEFLATE, M_WAITOK | M_ZERO);
179
180 NG_NODE_SET_PRIVATE(node, priv);
181
182 /* This node is not thread safe. */
183 NG_NODE_FORCE_WRITER(node);
184
185 /* Done */
186 return (0);
187 }
188
189 /*
190 * Give our OK for a hook to be added.
191 */
192 static int
ng_deflate_newhook(node_p node,hook_p hook,const char * name)193 ng_deflate_newhook(node_p node, hook_p hook, const char *name)
194 {
195 const priv_p priv = NG_NODE_PRIVATE(node);
196
197 if (NG_NODE_NUMHOOKS(node) > 0)
198 return (EINVAL);
199
200 if (strcmp(name, NG_DEFLATE_HOOK_COMP) == 0)
201 priv->compress = 1;
202 else if (strcmp(name, NG_DEFLATE_HOOK_DECOMP) == 0)
203 priv->compress = 0;
204 else
205 return (EINVAL);
206
207 return (0);
208 }
209
210 /*
211 * Receive a control message
212 */
213 static int
ng_deflate_rcvmsg(node_p node,item_p item,hook_p lasthook)214 ng_deflate_rcvmsg(node_p node, item_p item, hook_p lasthook)
215 {
216 const priv_p priv = NG_NODE_PRIVATE(node);
217 struct ng_mesg *resp = NULL;
218 int error = 0;
219 struct ng_mesg *msg;
220
221 NGI_GET_MSG(item, msg);
222
223 if (msg->header.typecookie != NGM_DEFLATE_COOKIE)
224 ERROUT(EINVAL);
225
226 switch (msg->header.cmd) {
227 case NGM_DEFLATE_CONFIG:
228 {
229 struct ng_deflate_config *const cfg
230 = (struct ng_deflate_config *)msg->data;
231
232 /* Check configuration. */
233 if (msg->header.arglen != sizeof(*cfg))
234 ERROUT(EINVAL);
235 if (cfg->enable) {
236 if (cfg->windowBits < 8 || cfg->windowBits > 15)
237 ERROUT(EINVAL);
238 } else
239 cfg->windowBits = 0;
240
241 /* Clear previous state. */
242 if (priv->cfg.enable) {
243 if (priv->compress)
244 deflateEnd(&priv->cx);
245 else
246 inflateEnd(&priv->cx);
247 priv->cfg.enable = 0;
248 }
249
250 /* Configuration is OK, reset to it. */
251 priv->cfg = *cfg;
252
253 if (priv->cfg.enable) {
254 priv->cx.next_in = NULL;
255 priv->cx.zalloc = z_alloc;
256 priv->cx.zfree = z_free;
257 int res;
258 if (priv->compress) {
259 if ((res = deflateInit2(&priv->cx,
260 Z_DEFAULT_COMPRESSION, Z_DEFLATED,
261 -cfg->windowBits, 8,
262 Z_DEFAULT_STRATEGY)) != Z_OK) {
263 log(LOG_NOTICE,
264 "deflateInit2: error %d, %s\n",
265 res, priv->cx.msg);
266 priv->cfg.enable = 0;
267 ERROUT(ENOMEM);
268 }
269 } else {
270 if ((res = inflateInit2(&priv->cx,
271 -cfg->windowBits)) != Z_OK) {
272 log(LOG_NOTICE,
273 "inflateInit2: error %d, %s\n",
274 res, priv->cx.msg);
275 priv->cfg.enable = 0;
276 ERROUT(ENOMEM);
277 }
278 }
279 }
280
281 /* Initialize other state. */
282 priv->seqnum = 0;
283
284 /* Save return address so we can send reset-req's */
285 priv->ctrlnode = NGI_RETADDR(item);
286 break;
287 }
288
289 case NGM_DEFLATE_RESETREQ:
290 ng_deflate_reset_req(node);
291 break;
292
293 case NGM_DEFLATE_GET_STATS:
294 case NGM_DEFLATE_CLR_STATS:
295 case NGM_DEFLATE_GETCLR_STATS:
296 /* Create response if requested. */
297 if (msg->header.cmd != NGM_DEFLATE_CLR_STATS) {
298 NG_MKRESPONSE(resp, msg,
299 sizeof(struct ng_deflate_stats), M_WAITOK | M_NULLOK);
300 if (resp == NULL)
301 ERROUT(ENOMEM);
302 bcopy(&priv->stats, resp->data,
303 sizeof(struct ng_deflate_stats));
304 }
305
306 /* Clear stats if requested. */
307 if (msg->header.cmd != NGM_DEFLATE_GET_STATS)
308 bzero(&priv->stats,
309 sizeof(struct ng_deflate_stats));
310 break;
311
312 default:
313 error = EINVAL;
314 break;
315 }
316 done:
317 NG_RESPOND_MSG(error, node, item, resp);
318 NG_FREE_MSG(msg);
319 return (error);
320 }
321
322 /*
323 * Receive incoming data on our hook.
324 */
325 static int
ng_deflate_rcvdata(hook_p hook,item_p item)326 ng_deflate_rcvdata(hook_p hook, item_p item)
327 {
328 const node_p node = NG_HOOK_NODE(hook);
329 const priv_p priv = NG_NODE_PRIVATE(node);
330 struct mbuf *m, *out;
331 int error;
332
333 if (!priv->cfg.enable) {
334 NG_FREE_ITEM(item);
335 return (ENXIO);
336 }
337
338 NGI_GET_M(item, m);
339 /* Compress */
340 if (priv->compress) {
341 if ((error = ng_deflate_compress(node, m, &out)) != 0) {
342 NG_FREE_ITEM(item);
343 log(LOG_NOTICE, "%s: error: %d\n", __func__, error);
344 return (error);
345 }
346
347 } else { /* Decompress */
348 if ((error = ng_deflate_decompress(node, m, &out)) != 0) {
349 NG_FREE_ITEM(item);
350 log(LOG_NOTICE, "%s: error: %d\n", __func__, error);
351 if (priv->ctrlnode != 0) {
352 struct ng_mesg *msg;
353
354 /* Need to send a reset-request. */
355 NG_MKMESSAGE(msg, NGM_DEFLATE_COOKIE,
356 NGM_DEFLATE_RESETREQ, 0, M_WAITOK | M_NULLOK);
357 if (msg == NULL)
358 return (error);
359 NG_SEND_MSG_ID(error, node, msg,
360 priv->ctrlnode, 0);
361 }
362 return (error);
363 }
364 }
365
366 NG_FWD_NEW_DATA(error, item, hook, out);
367 return (error);
368 }
369
370 /*
371 * Destroy node.
372 */
373 static int
ng_deflate_shutdown(node_p node)374 ng_deflate_shutdown(node_p node)
375 {
376 const priv_p priv = NG_NODE_PRIVATE(node);
377
378 /* Take down netgraph node. */
379 if (priv->cfg.enable) {
380 if (priv->compress)
381 deflateEnd(&priv->cx);
382 else
383 inflateEnd(&priv->cx);
384 }
385
386 kfree(priv, M_NETGRAPH_DEFLATE);
387 NG_NODE_SET_PRIVATE(node, NULL);
388 NG_NODE_UNREF(node); /* let the node escape */
389 return (0);
390 }
391
392 /*
393 * Hook disconnection
394 */
395 static int
ng_deflate_disconnect(hook_p hook)396 ng_deflate_disconnect(hook_p hook)
397 {
398 const node_p node = NG_HOOK_NODE(hook);
399 const priv_p priv = NG_NODE_PRIVATE(node);
400
401 if (priv->cfg.enable) {
402 if (priv->compress)
403 deflateEnd(&priv->cx);
404 else
405 inflateEnd(&priv->cx);
406 priv->cfg.enable = 0;
407 }
408
409 /* Go away if no longer connected. */
410 if ((NG_NODE_NUMHOOKS(node) == 0) && NG_NODE_IS_VALID(node))
411 ng_rmnode_self(node);
412 return (0);
413 }
414
415 /************************************************************************
416 HELPER STUFF
417 ************************************************************************/
418
419 /*
420 * Space allocation and freeing routines for use by zlib routines.
421 */
422
423 static void *
z_alloc(void * notused,u_int items,u_int size)424 z_alloc(void *notused, u_int items, u_int size)
425 {
426
427 return (kmalloc(items * size, M_NETGRAPH_DEFLATE, M_WAITOK | M_NULLOK));
428 }
429
430 static void
z_free(void * notused,void * ptr)431 z_free(void *notused, void *ptr)
432 {
433
434 kfree(ptr, M_NETGRAPH_DEFLATE);
435 }
436
437 /*
438 * Compress/encrypt a packet and put the result in a new mbuf at *resultp.
439 * The original mbuf is not free'd.
440 */
441 static int
ng_deflate_compress(node_p node,struct mbuf * m,struct mbuf ** resultp)442 ng_deflate_compress(node_p node, struct mbuf *m, struct mbuf **resultp)
443 {
444 const priv_p priv = NG_NODE_PRIVATE(node);
445 int outlen, inlen;
446 int rtn;
447
448 /* Initialize. */
449 *resultp = NULL;
450
451 inlen = m->m_pkthdr.len;
452
453 priv->stats.FramesPlain++;
454 priv->stats.InOctets+=inlen;
455
456 if (inlen > DEFLATE_BUF_SIZE) {
457 priv->stats.Errors++;
458 NG_FREE_M(m);
459 return (ENOMEM);
460 }
461
462 /* Work with contiguous regions of memory. */
463 m_copydata(m, 0, inlen, priv->inbuf);
464 outlen = DEFLATE_BUF_SIZE;
465
466 /* Compress "inbuf" into "outbuf". */
467 /* Prepare to compress. */
468 if (priv->inbuf[0] != 0) {
469 priv->cx.next_in = priv->inbuf;
470 priv->cx.avail_in = inlen;
471 } else {
472 priv->cx.next_in = priv->inbuf + 1; /* compress protocol */
473 priv->cx.avail_in = inlen - 1;
474 }
475 priv->cx.next_out = priv->outbuf + 2 + DEFLATE_HDRLEN;
476 priv->cx.avail_out = outlen - 2 - DEFLATE_HDRLEN;
477
478 /* Compress. */
479 rtn = deflate(&priv->cx, Z_PACKET_FLUSH);
480
481 /* Check return value. */
482 if (rtn != Z_OK) {
483 priv->stats.Errors++;
484 log(LOG_NOTICE, "ng_deflate: compression error: %d (%s)\n",
485 rtn, priv->cx.msg);
486 NG_FREE_M(m);
487 return (EINVAL);
488 }
489
490 /* Calculate resulting size. */
491 outlen -= priv->cx.avail_out;
492
493 /* If we can't compress this packet, send it as-is. */
494 if (outlen > inlen) {
495 /* Return original packet uncompressed. */
496 *resultp = m;
497 priv->stats.FramesUncomp++;
498 priv->stats.OutOctets+=inlen;
499 } else {
500 NG_FREE_M(m);
501
502 /* Install header. */
503 ((u_int16_t *)priv->outbuf)[0] = htons(PROT_COMPD);
504 ((u_int16_t *)priv->outbuf)[1] = htons(priv->seqnum);
505
506 /* Return packet in an mbuf. */
507 *resultp = m_devget(priv->outbuf, outlen, 0, NULL);
508 if (*resultp == NULL) {
509 priv->stats.Errors++;
510 return (ENOMEM);
511 }
512 priv->stats.FramesComp++;
513 priv->stats.OutOctets+=outlen;
514 }
515
516 /* Update sequence number. */
517 priv->seqnum++;
518
519 return (0);
520 }
521
522 /*
523 * Decompress/decrypt packet and put the result in a new mbuf at *resultp.
524 * The original mbuf is not free'd.
525 */
526 static int
ng_deflate_decompress(node_p node,struct mbuf * m,struct mbuf ** resultp)527 ng_deflate_decompress(node_p node, struct mbuf *m, struct mbuf **resultp)
528 {
529 const priv_p priv = NG_NODE_PRIVATE(node);
530 int outlen, inlen;
531 int rtn;
532 uint16_t proto;
533 int offset;
534 uint16_t rseqnum;
535
536 /* Initialize. */
537 *resultp = NULL;
538
539 inlen = m->m_pkthdr.len;
540
541 if (inlen > DEFLATE_BUF_SIZE) {
542 priv->stats.Errors++;
543 NG_FREE_M(m);
544 priv->seqnum = 0;
545 return (ENOMEM);
546 }
547
548 /* Work with contiguous regions of memory. */
549 m_copydata(m, 0, inlen, priv->inbuf);
550
551 /* Separate proto. */
552 if ((priv->inbuf[0] & 0x01) != 0) {
553 proto = priv->inbuf[0];
554 offset = 1;
555 } else {
556 proto = ntohs(((uint16_t *)priv->inbuf)[0]);
557 offset = 2;
558 }
559
560 priv->stats.InOctets += inlen;
561
562 /* Packet is compressed, so decompress. */
563 if (proto == PROT_COMPD) {
564 priv->stats.FramesComp++;
565
566 /* Check sequence number. */
567 rseqnum = ntohs(((uint16_t *)(priv->inbuf + offset))[0]);
568 offset += 2;
569 if (rseqnum != priv->seqnum) {
570 priv->stats.Errors++;
571 log(LOG_NOTICE, "ng_deflate: wrong sequence: %u "
572 "instead of %u\n", rseqnum, priv->seqnum);
573 NG_FREE_M(m);
574 priv->seqnum = 0;
575 return (EPIPE);
576 }
577
578 outlen = DEFLATE_BUF_SIZE;
579
580 /* Decompress "inbuf" into "outbuf". */
581 /* Prepare to decompress. */
582 priv->cx.next_in = priv->inbuf + offset;
583 priv->cx.avail_in = inlen - offset;
584 /* Reserve space for protocol decompression. */
585 priv->cx.next_out = priv->outbuf + 1;
586 priv->cx.avail_out = outlen - 1;
587
588 /* Decompress. */
589 rtn = inflate(&priv->cx, Z_PACKET_FLUSH);
590
591 /* Check return value. */
592 if (rtn != Z_OK && rtn != Z_STREAM_END) {
593 priv->stats.Errors++;
594 NG_FREE_M(m);
595 priv->seqnum = 0;
596 log(LOG_NOTICE, "%s: decompression error: %d (%s)\n",
597 __func__, rtn, priv->cx.msg);
598
599 switch (rtn) {
600 case Z_MEM_ERROR:
601 return (ENOMEM);
602 case Z_DATA_ERROR:
603 return (EIO);
604 default:
605 return (EINVAL);
606 }
607 }
608
609 /* Calculate resulting size. */
610 outlen -= priv->cx.avail_out;
611
612 NG_FREE_M(m);
613
614 /* Decompress protocol. */
615 if ((priv->outbuf[1] & 0x01) != 0) {
616 priv->outbuf[0] = 0;
617 /* Return packet in an mbuf. */
618 *resultp = m_devget(priv->outbuf, outlen, 0, NULL);
619 } else {
620 outlen--;
621 /* Return packet in an mbuf. */
622 *resultp = m_devget(priv->outbuf + 1, outlen, 0, NULL);
623 }
624 if (*resultp == NULL) {
625 priv->stats.Errors++;
626 priv->seqnum = 0;
627 return (ENOMEM);
628 }
629 priv->stats.FramesPlain++;
630 priv->stats.OutOctets+=outlen;
631
632 } else { /* Packet is not compressed, just update dictionary. */
633 priv->stats.FramesUncomp++;
634 if (priv->inbuf[0] == 0) {
635 priv->cx.next_in = priv->inbuf + 1; /* compress protocol */
636 priv->cx.avail_in = inlen - 1;
637 } else {
638 priv->cx.next_in = priv->inbuf;
639 priv->cx.avail_in = inlen;
640 }
641
642 rtn = inflateIncomp(&priv->cx);
643
644 /* Check return value */
645 if (rtn != Z_OK) {
646 priv->stats.Errors++;
647 log(LOG_NOTICE, "%s: inflateIncomp error: %d (%s)\n",
648 __func__, rtn, priv->cx.msg);
649 NG_FREE_M(m);
650 priv->seqnum = 0;
651 return (EINVAL);
652 }
653
654 *resultp = m;
655 priv->stats.FramesPlain++;
656 priv->stats.OutOctets += inlen;
657 }
658
659 /* Update sequence number. */
660 priv->seqnum++;
661
662 return (0);
663 }
664
665 /*
666 * The peer has sent us a CCP ResetRequest, so reset our transmit state.
667 */
668 static void
ng_deflate_reset_req(node_p node)669 ng_deflate_reset_req(node_p node)
670 {
671 const priv_p priv = NG_NODE_PRIVATE(node);
672
673 priv->seqnum = 0;
674 if (priv->cfg.enable) {
675 if (priv->compress)
676 deflateReset(&priv->cx);
677 else
678 inflateReset(&priv->cx);
679 }
680 }
681
682