2cfc86732464fca97976c2b4daf0b4e8549dfcb1
[dragonfly.git] / sys / netgraph7 / ng_vjc.c
1
2 /*
3  * ng_vjc.c
4  */
5
6 /*-
7  * Copyright (c) 1996-1999 Whistle Communications, Inc.
8  * All rights reserved.
9  * 
10  * Subject to the following obligations and disclaimer of warranty, use and
11  * redistribution of this software, in source or object code forms, with or
12  * without modifications are expressly permitted by Whistle Communications;
13  * provided, however, that:
14  * 1. Any and all reproductions of the source or object code must include the
15  *    copyright notice above and the following disclaimer of warranties; and
16  * 2. No rights are granted, in any manner or form, to use Whistle
17  *    Communications, Inc. trademarks, including the mark "WHISTLE
18  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
19  *    such appears in the above copyright notice or in the software.
20  * 
21  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
22  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
23  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
24  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
26  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
27  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
28  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
29  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
30  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
31  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
32  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
33  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
37  * OF SUCH DAMAGE.
38  *
39  * Author: Archie Cobbs <archie@freebsd.org>
40  *
41  * $FreeBSD: src/sys/netgraph/ng_vjc.c,v 1.26 2005/12/04 00:25:03 ru Exp $
42  * $DragonFly: src/sys/netgraph7/ng_vjc.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
43  * $Whistle: ng_vjc.c,v 1.17 1999/11/01 09:24:52 julian Exp $
44  */
45
46 /*
47  * This node performs Van Jacobson IP header (de)compression.
48  * You must have included net/slcompress.c in your kernel compilation.
49  */
50
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/errno.h>
54 #include <sys/kernel.h>
55 #include <sys/mbuf.h>
56 #include <sys/malloc.h>
57 #include <sys/errno.h>
58
59 #include "ng_message.h"
60 #include "netgraph.h"
61 #include "ng_parse.h"
62 #include "ng_vjc.h"
63
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/ip.h>
67 #include <netinet/tcp.h>
68
69 #include <net/slcompress.h>
70
71 /* Check agreement with slcompress.c */
72 #if MAX_STATES != NG_VJC_MAX_CHANNELS
73 #error NG_VJC_MAX_CHANNELS must be the same as MAX_STATES
74 #endif
75
76 /* Maximum length of a compressed TCP VJ header */
77 #define MAX_VJHEADER            19
78
79 /* Node private data */
80 struct ng_vjc_private {
81         struct  ngm_vjc_config conf;
82         struct  slcompress slc;
83         hook_p  ip;
84         hook_p  vjcomp;
85         hook_p  vjuncomp;
86         hook_p  vjip;
87 };
88 typedef struct ng_vjc_private *priv_p;
89
90 #define ERROUT(x)       do { error = (x); goto done; } while (0)
91
92 /* Netgraph node methods */
93 static ng_constructor_t ng_vjc_constructor;
94 static ng_rcvmsg_t      ng_vjc_rcvmsg;
95 static ng_shutdown_t    ng_vjc_shutdown;
96 static ng_newhook_t     ng_vjc_newhook;
97 static ng_rcvdata_t     ng_vjc_rcvdata;
98 static ng_disconnect_t  ng_vjc_disconnect;
99
100 /* Helper stuff */
101 static struct mbuf *ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP);
102
103 /* Parse type for struct ngm_vjc_config */
104 static const struct ng_parse_struct_field ng_vjc_config_type_fields[]
105         = NG_VJC_CONFIG_TYPE_INFO;
106 static const struct ng_parse_type ng_vjc_config_type = {
107         &ng_parse_struct_type,
108         &ng_vjc_config_type_fields
109 };
110
111 /* Parse type for the 'last_cs' and 'cs_next' fields in struct slcompress,
112    which are pointers converted to integer indices, so parse them that way. */
113 #ifndef __LP64__
114 #define NG_VJC_TSTATE_PTR_TYPE  &ng_parse_uint32_type
115 #else
116 #define NG_VJC_TSTATE_PTR_TYPE  &ng_parse_uint64_type
117 #endif
118
119 /* Parse type for the 'cs_hdr' field in a struct cstate. Ideally we would
120    like to use a 'struct ip' type instead of a simple array of bytes. */
121 static const struct ng_parse_fixedarray_info ng_vjc_cs_hdr_type_info = {
122         &ng_parse_hint8_type,
123         MAX_HDR
124 };
125 static const struct ng_parse_type ng_vjc_cs_hdr_type = {
126         &ng_parse_fixedarray_type,
127         &ng_vjc_cs_hdr_type_info
128 };
129
130 /* Parse type for a struct cstate */
131 static const struct ng_parse_struct_field ng_vjc_cstate_type_fields[] = {
132         { "cs_next",            NG_VJC_TSTATE_PTR_TYPE          },
133         { "cs_hlen",            &ng_parse_uint16_type           },
134         { "cs_id",              &ng_parse_uint8_type            },
135         { "cs_filler",          &ng_parse_uint8_type            },
136         { "cs_hdr",             &ng_vjc_cs_hdr_type             },
137         { NULL }
138 };
139 static const struct ng_parse_type ng_vjc_cstate_type = {
140         &ng_parse_struct_type,
141         &ng_vjc_cstate_type_fields
142 };
143
144 /* Parse type for an array of MAX_STATES struct cstate's, ie, tstate & rstate */
145 static const struct ng_parse_fixedarray_info ng_vjc_cstatearray_type_info = {
146         &ng_vjc_cstate_type,
147         MAX_STATES
148 };
149 static const struct ng_parse_type ng_vjc_cstatearray_type = {
150         &ng_parse_fixedarray_type,
151         &ng_vjc_cstatearray_type_info
152 };
153
154 /* Parse type for struct slcompress. Keep this in sync with the
155    definition of struct slcompress defined in <net/slcompress.h> */
156 static const struct ng_parse_struct_field ng_vjc_slcompress_type_fields[] = {
157         { "last_cs",            NG_VJC_TSTATE_PTR_TYPE          },
158         { "last_recv",          &ng_parse_uint8_type            },
159         { "last_xmit",          &ng_parse_uint8_type            },
160         { "flags",              &ng_parse_hint16_type           },
161 #ifndef SL_NO_STATS
162         { "sls_packets",        &ng_parse_uint32_type           },
163         { "sls_compressed",     &ng_parse_uint32_type           },
164         { "sls_searches",       &ng_parse_uint32_type           },
165         { "sls_misses",         &ng_parse_uint32_type           },
166         { "sls_uncompressedin", &ng_parse_uint32_type           },
167         { "sls_compressedin",   &ng_parse_uint32_type           },
168         { "sls_errorin",        &ng_parse_uint32_type           },
169         { "sls_tossed",         &ng_parse_uint32_type           },
170 #endif
171         { "tstate",             &ng_vjc_cstatearray_type        },
172         { "rstate",             &ng_vjc_cstatearray_type        },
173         { NULL }
174 };
175 static const struct ng_parse_type ng_vjc_slcompress_type = {
176         &ng_parse_struct_type,
177         &ng_vjc_slcompress_type_fields
178 };
179
180 /* List of commands and how to convert arguments to/from ASCII */
181 static const struct ng_cmdlist ng_vjc_cmds[] = {
182         {
183           NGM_VJC_COOKIE,
184           NGM_VJC_SET_CONFIG,
185           "setconfig",
186           &ng_vjc_config_type,
187           NULL
188         },
189         {
190           NGM_VJC_COOKIE,
191           NGM_VJC_GET_CONFIG,
192           "getconfig",
193           NULL,
194           &ng_vjc_config_type,
195         },
196         {
197           NGM_VJC_COOKIE,
198           NGM_VJC_GET_STATE,
199           "getstate",
200           NULL,
201           &ng_vjc_slcompress_type,
202         },
203         {
204           NGM_VJC_COOKIE,
205           NGM_VJC_CLR_STATS,
206           "clrstats",
207           NULL,
208           NULL,
209         },
210         {
211           NGM_VJC_COOKIE,
212           NGM_VJC_RECV_ERROR,
213           "recverror",
214           NULL,
215           NULL,
216         },
217         { 0 }
218 };
219
220 /* Node type descriptor */
221 static struct ng_type ng_vjc_typestruct = {
222         .version =      NG_ABI_VERSION,
223         .name =         NG_VJC_NODE_TYPE,
224         .constructor =  ng_vjc_constructor,
225         .rcvmsg =       ng_vjc_rcvmsg,
226         .shutdown =     ng_vjc_shutdown,
227         .newhook =      ng_vjc_newhook,
228         .rcvdata =      ng_vjc_rcvdata,
229         .disconnect =   ng_vjc_disconnect,
230         .cmdlist =      ng_vjc_cmds,
231 };
232 NETGRAPH_INIT(vjc, &ng_vjc_typestruct);
233
234 /************************************************************************
235                         NETGRAPH NODE METHODS
236  ************************************************************************/
237
238 /*
239  * Create a new node
240  */
241 static int
242 ng_vjc_constructor(node_p node)
243 {
244         priv_p priv;
245
246         /* Allocate private structure */
247         MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK | M_NULLOK | M_ZERO);
248         if (priv == NULL)
249                 return (ENOMEM);
250
251         NG_NODE_SET_PRIVATE(node, priv);
252
253         /* Done */
254         return (0);
255 }
256
257 /*
258  * Add a new hook
259  */
260 static int
261 ng_vjc_newhook(node_p node, hook_p hook, const char *name)
262 {
263         const priv_p priv = NG_NODE_PRIVATE(node);
264         hook_p *hookp;
265
266         /* Get hook */
267         if (strcmp(name, NG_VJC_HOOK_IP) == 0)
268                 hookp = &priv->ip;
269         else if (strcmp(name, NG_VJC_HOOK_VJCOMP) == 0)
270                 hookp = &priv->vjcomp;
271         else if (strcmp(name, NG_VJC_HOOK_VJUNCOMP) == 0)
272                 hookp = &priv->vjuncomp;
273         else if (strcmp(name, NG_VJC_HOOK_VJIP) == 0)
274                 hookp = &priv->vjip;
275         else
276                 return (EINVAL);
277
278         /* See if already connected */
279         if (*hookp)
280                 return (EISCONN);
281
282         /* OK */
283         *hookp = hook;
284         return (0);
285 }
286
287 /*
288  * Receive a control message
289  */
290 static int
291 ng_vjc_rcvmsg(node_p node, item_p item, hook_p lasthook)
292 {
293         const priv_p priv = NG_NODE_PRIVATE(node);
294         struct ng_mesg *resp = NULL;
295         int error = 0;
296         struct ng_mesg *msg;
297
298         NGI_GET_MSG(item, msg);
299         /* Check type cookie */
300         switch (msg->header.typecookie) {
301         case NGM_VJC_COOKIE:
302                 switch (msg->header.cmd) {
303                 case NGM_VJC_SET_CONFIG:
304                     {
305                         struct ngm_vjc_config *const c =
306                                 (struct ngm_vjc_config *) msg->data;
307
308                         if (msg->header.arglen != sizeof(*c))
309                                 ERROUT(EINVAL);
310                         if ((priv->conf.enableComp || priv->conf.enableDecomp)
311                             && (c->enableComp || c->enableDecomp))
312                                 ERROUT(EALREADY);
313                         if (c->enableComp) {
314                                 if (c->maxChannel > NG_VJC_MAX_CHANNELS - 1
315                                     || c->maxChannel < NG_VJC_MIN_CHANNELS - 1)
316                                         ERROUT(EINVAL);
317                         } else
318                                 c->maxChannel = NG_VJC_MAX_CHANNELS - 1;
319                         if (c->enableComp != 0 || c->enableDecomp != 0) {
320                                 bzero(&priv->slc, sizeof(priv->slc));
321                                 sl_compress_init(&priv->slc, c->maxChannel);
322                         }
323                         priv->conf = *c;
324                         break;
325                     }
326                 case NGM_VJC_GET_CONFIG:
327                     {
328                         struct ngm_vjc_config *conf;
329
330                         NG_MKRESPONSE(resp, msg, sizeof(*conf), M_WAITOK | M_NULLOK);
331                         if (resp == NULL)
332                                 ERROUT(ENOMEM);
333                         conf = (struct ngm_vjc_config *)resp->data;
334                         *conf = priv->conf;
335                         break;
336                     }
337                 case NGM_VJC_GET_STATE:
338                     {
339                         const struct slcompress *const sl0 = &priv->slc;
340                         struct slcompress *sl;
341                         u_int16_t index;
342                         int i;
343
344                         /* Get response structure */
345                         NG_MKRESPONSE(resp, msg, sizeof(*sl), M_WAITOK | M_NULLOK);
346                         if (resp == NULL)
347                                 ERROUT(ENOMEM);
348                         sl = (struct slcompress *)resp->data;
349                         *sl = *sl0;
350
351                         /* Replace pointers with integer indicies */
352                         if (sl->last_cs != NULL) {
353                                 index = sl0->last_cs - sl0->tstate;
354                                 bzero(&sl->last_cs, sizeof(sl->last_cs));
355                                 *((u_int16_t *)&sl->last_cs) = index;
356                         }
357                         for (i = 0; i < MAX_STATES; i++) {
358                                 struct cstate *const cs = &sl->tstate[i];
359
360                                 index = sl0->tstate[i].cs_next - sl0->tstate;
361                                 bzero(&cs->cs_next, sizeof(cs->cs_next));
362                                 *((u_int16_t *)&cs->cs_next) = index;
363                         }
364                         break;
365                     }
366                 case NGM_VJC_CLR_STATS:
367                         priv->slc.sls_packets = 0;
368                         priv->slc.sls_compressed = 0;
369                         priv->slc.sls_searches = 0;
370                         priv->slc.sls_misses = 0;
371                         priv->slc.sls_uncompressedin = 0;
372                         priv->slc.sls_compressedin = 0;
373                         priv->slc.sls_errorin = 0;
374                         priv->slc.sls_tossed = 0;
375                         break;
376                 case NGM_VJC_RECV_ERROR:
377                         sl_uncompress_tcp(NULL, 0, TYPE_ERROR, &priv->slc);
378                         break;
379                 default:
380                         error = EINVAL;
381                         break;
382                 }
383                 break;
384         default:
385                 error = EINVAL;
386                 break;
387         }
388 done:
389         NG_RESPOND_MSG(error, node, item, resp);
390         NG_FREE_MSG(msg);
391         return (error);
392 }
393
394 /*
395  * Receive data
396  */
397 static int
398 ng_vjc_rcvdata(hook_p hook, item_p item)
399 {
400         const node_p node = NG_HOOK_NODE(hook);
401         const priv_p priv = NG_NODE_PRIVATE(node);
402         int error = 0;
403         struct mbuf *m;
404
405         NGI_GET_M(item, m);
406         if (hook == priv->ip) {                 /* outgoing packet */
407                 u_int type = TYPE_IP;
408
409                 /* Compress packet if enabled and proto is TCP */
410                 if (priv->conf.enableComp) {
411                         struct ip *ip;
412
413                         if ((m = ng_vjc_pulluphdrs(m, 0)) == NULL) {
414                                 NG_FREE_ITEM(item);
415                                 return (ENOBUFS);
416                         }
417                         ip = mtod(m, struct ip *);
418                         if (ip->ip_p == IPPROTO_TCP) {
419                                 const int origLen = m->m_len;
420
421                                 type = sl_compress_tcp(m, ip,
422                                     &priv->slc, priv->conf.compressCID);
423                                 m->m_pkthdr.len += m->m_len - origLen;
424                         }
425                 }
426
427                 /* Dispatch to the appropriate outgoing hook */
428                 switch (type) {
429                 case TYPE_IP:
430                         hook = priv->vjip;
431                         break;
432                 case TYPE_UNCOMPRESSED_TCP:
433                         hook = priv->vjuncomp;
434                         break;
435                 case TYPE_COMPRESSED_TCP:
436                         hook = priv->vjcomp;
437                         break;
438                 default:
439                         panic("%s: type=%d", __func__, type);
440                 }
441         } else if (hook == priv->vjcomp) {      /* incoming compressed packet */
442                 int vjlen, need2pullup;
443                 struct mbuf *hm;
444                 u_char *hdr;
445                 u_int hlen;
446
447                 /* Are we decompressing? */
448                 if (!priv->conf.enableDecomp) {
449                         NG_FREE_M(m);
450                         NG_FREE_ITEM(item);
451                         return (ENXIO);
452                 }
453
454                 /* Pull up the necessary amount from the mbuf */
455                 need2pullup = MAX_VJHEADER;
456                 if (need2pullup > m->m_pkthdr.len)
457                         need2pullup = m->m_pkthdr.len;
458                 if (m->m_len < need2pullup
459                     && (m = m_pullup(m, need2pullup)) == NULL) {
460                         priv->slc.sls_errorin++;
461                         NG_FREE_ITEM(item);
462                         return (ENOBUFS);
463                 }
464
465                 /* Uncompress packet to reconstruct TCP/IP header */
466                 vjlen = sl_uncompress_tcp_core(mtod(m, u_char *),
467                     m->m_len, m->m_pkthdr.len, TYPE_COMPRESSED_TCP,
468                     &priv->slc, &hdr, &hlen);
469                 if (vjlen <= 0) {
470                         NG_FREE_M(m);
471                         NG_FREE_ITEM(item);
472                         return (EINVAL);
473                 }
474                 m_adj(m, vjlen);
475
476                 /* Copy the reconstructed TCP/IP headers into a new mbuf */
477                 MGETHDR(hm, MB_DONTWAIT, MT_DATA);
478                 if (hm == NULL) {
479                         priv->slc.sls_errorin++;
480                         NG_FREE_M(m);
481                         NG_FREE_ITEM(item);
482                         return (ENOBUFS);
483                 }
484                 hm->m_len = 0;
485                 hm->m_pkthdr.rcvif = NULL;
486                 if (hlen > MHLEN) {             /* unlikely, but can happen */
487                         MCLGET(hm, MB_DONTWAIT);
488                         if ((hm->m_flags & M_EXT) == 0) {
489                                 m_freem(hm);
490                                 priv->slc.sls_errorin++;
491                                 NG_FREE_M(m);
492                                 NG_FREE_ITEM(item);
493                                 return (ENOBUFS);
494                         }
495                 }
496                 bcopy(hdr, mtod(hm, u_char *), hlen);
497                 hm->m_len = hlen;
498
499                 /* Glue TCP/IP headers and rest of packet together */
500                 hm->m_next = m;
501                 hm->m_pkthdr.len = hlen + m->m_pkthdr.len;
502                 m = hm;
503                 hook = priv->ip;
504         } else if (hook == priv->vjuncomp) {    /* incoming uncompressed pkt */
505                 u_char *hdr;
506                 u_int hlen;
507
508                 /* Are we decompressing? */
509                 if (!priv->conf.enableDecomp) {
510                         NG_FREE_M(m);
511                         NG_FREE_ITEM(item);
512                         return (ENXIO);
513                 }
514
515                 /* Pull up IP+TCP headers */
516                 if ((m = ng_vjc_pulluphdrs(m, 1)) == NULL) {
517                         NG_FREE_ITEM(item);
518                         return (ENOBUFS);
519                 }
520
521                 /* Run packet through uncompressor */
522                 if (sl_uncompress_tcp_core(mtod(m, u_char *),
523                     m->m_len, m->m_pkthdr.len, TYPE_UNCOMPRESSED_TCP,
524                     &priv->slc, &hdr, &hlen) < 0) {
525                         NG_FREE_M(m);
526                         NG_FREE_ITEM(item);
527                         return (EINVAL);
528                 }
529                 hook = priv->ip;
530         } else if (hook == priv->vjip)  /* incoming regular packet (bypass) */
531                 hook = priv->ip;
532         else
533                 panic("%s: unknown hook", __func__);
534
535         /* Send result back out */
536         NG_FWD_NEW_DATA(error, item, hook, m);
537         return (error);
538 }
539
540 /*
541  * Shutdown node
542  */
543 static int
544 ng_vjc_shutdown(node_p node)
545 {
546         const priv_p priv = NG_NODE_PRIVATE(node);
547
548         bzero(priv, sizeof(*priv));
549         FREE(priv, M_NETGRAPH);
550         NG_NODE_SET_PRIVATE(node, NULL);
551         NG_NODE_UNREF(node);
552         return (0);
553 }
554
555 /*
556  * Hook disconnection
557  */
558 static int
559 ng_vjc_disconnect(hook_p hook)
560 {
561         const node_p node = NG_HOOK_NODE(hook);
562         const priv_p priv = NG_NODE_PRIVATE(node);
563
564         /* Zero out hook pointer */
565         if (hook == priv->ip)
566                 priv->ip = NULL;
567         else if (hook == priv->vjcomp)
568                 priv->vjcomp = NULL;
569         else if (hook == priv->vjuncomp)
570                 priv->vjuncomp = NULL;
571         else if (hook == priv->vjip)
572                 priv->vjip = NULL;
573         else
574                 panic("%s: unknown hook", __func__);
575
576         /* Go away if no hooks left */
577         if ((NG_NODE_NUMHOOKS(node) == 0)
578         && (NG_NODE_IS_VALID(node)))
579                 ng_rmnode_self(node);
580         return (0);
581 }
582
583 /************************************************************************
584                         HELPER STUFF
585  ************************************************************************/
586
587 /*
588  * Pull up the full IP and TCP headers of a packet. If packet is not
589  * a TCP packet, just pull up the IP header.
590  */
591 static struct mbuf *
592 ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP)
593 {
594         struct ip *ip;
595         struct tcphdr *tcp;
596         int ihlen, thlen;
597
598         if (m->m_len < sizeof(*ip) && (m = m_pullup(m, sizeof(*ip))) == NULL)
599                 return (NULL);
600         ip = mtod(m, struct ip *);
601         if (!knownTCP && ip->ip_p != IPPROTO_TCP)
602                 return (m);
603         ihlen = ip->ip_hl << 2;
604         if (m->m_len < ihlen + sizeof(*tcp)) {
605                 if ((m = m_pullup(m, ihlen + sizeof(*tcp))) == NULL)
606                         return (NULL);
607                 ip = mtod(m, struct ip *);
608         }
609         tcp = (struct tcphdr *)((u_char *)ip + ihlen);
610         thlen = tcp->th_off << 2;
611         if (m->m_len < ihlen + thlen)
612                 m = m_pullup(m, ihlen + thlen);
613         return (m);
614 }
615