For kmalloc(), MALLOC() and contigmalloc(), use M_ZERO instead of
[dragonfly.git] / sys / netgraph / vjc / ng_vjc.c
1
2 /*
3  * ng_vjc.c
4  *
5  * Copyright (c) 1996-1999 Whistle Communications, Inc.
6  * All rights reserved.
7  * 
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  * 
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  *
37  * Author: Archie Cobbs <archie@freebsd.org>
38  *
39  * $FreeBSD: src/sys/netgraph/ng_vjc.c,v 1.9.2.5 2002/07/02 23:44:03 archie Exp $
40  * $DragonFly: src/sys/netgraph/vjc/ng_vjc.c,v 1.8 2008/01/05 14:02:40 swildner Exp $
41  * $Whistle: ng_vjc.c,v 1.17 1999/11/01 09:24:52 julian Exp $
42  */
43
44 /*
45  * This node performs Van Jacobson IP header (de)compression.
46  * You must have included net/slcompress.c in your kernel compilation.
47  */
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/errno.h>
52 #include <sys/kernel.h>
53 #include <sys/mbuf.h>
54 #include <sys/malloc.h>
55 #include <sys/errno.h>
56
57 #include <netgraph/ng_message.h>
58 #include <netgraph/netgraph.h>
59 #include <netgraph/ng_parse.h>
60 #include "ng_vjc.h"
61
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/ip.h>
65 #include <netinet/tcp.h>
66
67 #include <net/slcompress.h>
68
69 /* Check agreement with slcompress.c */
70 #if MAX_STATES != NG_VJC_MAX_CHANNELS
71 #error NG_VJC_MAX_CHANNELS must be the same as MAX_STATES
72 #endif
73
74 /* Maximum length of a compressed TCP VJ header */
75 #define MAX_VJHEADER            19
76
77 /* Node private data */
78 struct ng_vjc_private {
79         struct  ngm_vjc_config conf;
80         struct  slcompress slc;
81         hook_p  ip;
82         hook_p  vjcomp;
83         hook_p  vjuncomp;
84         hook_p  vjip;
85 };
86 typedef struct ng_vjc_private *priv_p;
87
88 #define ERROUT(x)       do { error = (x); goto done; } while (0)
89
90 /* Netgraph node methods */
91 static ng_constructor_t ng_vjc_constructor;
92 static ng_rcvmsg_t      ng_vjc_rcvmsg;
93 static ng_shutdown_t    ng_vjc_rmnode;
94 static ng_newhook_t     ng_vjc_newhook;
95 static ng_rcvdata_t     ng_vjc_rcvdata;
96 static ng_disconnect_t  ng_vjc_disconnect;
97
98 /* Helper stuff */
99 static struct mbuf *ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP);
100
101 /* Parse type for struct ngm_vjc_config */
102 static const struct ng_parse_struct_field ng_vjc_config_type_fields[]
103         = NG_VJC_CONFIG_TYPE_INFO;
104 static const struct ng_parse_type ng_vjc_config_type = {
105         &ng_parse_struct_type,
106         &ng_vjc_config_type_fields
107 };
108
109 /* Parse type for the 'last_cs' and 'cs_next' fields in struct slcompress,
110    which are pointers converted to integer indices, so parse them that way. */
111 #if _MACHINE_ARCH == i386
112 #define NG_VJC_TSTATE_PTR_TYPE  &ng_parse_uint32_type
113 #else
114 #error Unsupported _MACHINE_ARCH
115 #endif
116
117 /* Parse type for the 'cs_hdr' field in a struct cstate. Ideally we would
118    like to use a 'struct ip' type instead of a simple array of bytes. */
119 static const struct ng_parse_fixedarray_info ng_vjc_cs_hdr_type_info = {
120         &ng_parse_hint8_type,
121         MAX_HDR
122 };
123 static const struct ng_parse_type ng_vjc_cs_hdr_type = {
124         &ng_parse_fixedarray_type,
125         &ng_vjc_cs_hdr_type_info
126 };
127
128 /* Parse type for a struct cstate */
129 static const struct ng_parse_struct_field ng_vjc_cstate_type_fields[] = {
130         { "cs_next",            NG_VJC_TSTATE_PTR_TYPE          },
131         { "cs_hlen",            &ng_parse_uint16_type           },
132         { "cs_id",              &ng_parse_uint8_type            },
133         { "cs_filler",          &ng_parse_uint8_type            },
134         { "cs_hdr",             &ng_vjc_cs_hdr_type             },
135         { NULL }
136 };
137 static const struct ng_parse_type ng_vjc_cstate_type = {
138         &ng_parse_struct_type,
139         &ng_vjc_cstate_type_fields
140 };
141
142 /* Parse type for an array of MAX_STATES struct cstate's, ie, tstate & rstate */
143 static const struct ng_parse_fixedarray_info ng_vjc_cstatearray_type_info = {
144         &ng_vjc_cstate_type,
145         MAX_STATES
146 };
147 static const struct ng_parse_type ng_vjc_cstatearray_type = {
148         &ng_parse_fixedarray_type,
149         &ng_vjc_cstatearray_type_info
150 };
151
152 /* Parse type for struct slcompress. Keep this in sync with the
153    definition of struct slcompress defined in <net/slcompress.h> */
154 static const struct ng_parse_struct_field ng_vjc_slcompress_type_fields[] = {
155         { "last_cs",            NG_VJC_TSTATE_PTR_TYPE          },
156         { "last_recv",          &ng_parse_uint8_type            },
157         { "last_xmit",          &ng_parse_uint8_type            },
158         { "flags",              &ng_parse_hint16_type           },
159 #ifndef SL_NO_STATS
160         { "sls_packets",        &ng_parse_uint32_type           },
161         { "sls_compressed",     &ng_parse_uint32_type           },
162         { "sls_searches",       &ng_parse_uint32_type           },
163         { "sls_misses",         &ng_parse_uint32_type           },
164         { "sls_uncompressedin", &ng_parse_uint32_type           },
165         { "sls_compressedin",   &ng_parse_uint32_type           },
166         { "sls_errorin",        &ng_parse_uint32_type           },
167         { "sls_tossed",         &ng_parse_uint32_type           },
168 #endif
169         { "tstate",             &ng_vjc_cstatearray_type        },
170         { "rstate",             &ng_vjc_cstatearray_type        },
171         { NULL }
172 };
173 static const struct ng_parse_type ng_vjc_slcompress_type = {
174         &ng_parse_struct_type,
175         &ng_vjc_slcompress_type_fields
176 };
177
178 /* List of commands and how to convert arguments to/from ASCII */
179 static const struct ng_cmdlist ng_vjc_cmds[] = {
180         {
181           NGM_VJC_COOKIE,
182           NGM_VJC_SET_CONFIG,
183           "setconfig",
184           &ng_vjc_config_type,
185           NULL
186         },
187         {
188           NGM_VJC_COOKIE,
189           NGM_VJC_GET_CONFIG,
190           "getconfig",
191           NULL,
192           &ng_vjc_config_type,
193         },
194         {
195           NGM_VJC_COOKIE,
196           NGM_VJC_GET_STATE,
197           "getstate",
198           NULL,
199           &ng_vjc_slcompress_type,
200         },
201         {
202           NGM_VJC_COOKIE,
203           NGM_VJC_CLR_STATS,
204           "clrstats",
205           NULL,
206           NULL,
207         },
208         {
209           NGM_VJC_COOKIE,
210           NGM_VJC_RECV_ERROR,
211           "recverror",
212           NULL,
213           NULL,
214         },
215         { 0 }
216 };
217
218 /* Node type descriptor */
219 static struct ng_type ng_vjc_typestruct = {
220         NG_VERSION,
221         NG_VJC_NODE_TYPE,
222         NULL,
223         ng_vjc_constructor,
224         ng_vjc_rcvmsg,
225         ng_vjc_rmnode,
226         ng_vjc_newhook,
227         NULL,
228         NULL,
229         ng_vjc_rcvdata,
230         ng_vjc_rcvdata,
231         ng_vjc_disconnect,
232         ng_vjc_cmds
233 };
234 NETGRAPH_INIT(vjc, &ng_vjc_typestruct);
235
236 /************************************************************************
237                         NETGRAPH NODE METHODS
238  ************************************************************************/
239
240 /*
241  * Create a new node
242  */
243 static int
244 ng_vjc_constructor(node_p *nodep)
245 {
246         priv_p priv;
247         int error;
248
249         /* Allocate private structure */
250         MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
251         if (priv == NULL)
252                 return (ENOMEM);
253
254         /* Call generic node constructor */
255         if ((error = ng_make_node_common(&ng_vjc_typestruct, nodep))) {
256                 FREE(priv, M_NETGRAPH);
257                 return (error);
258         }
259         (*nodep)->private = priv;
260
261         /* Done */
262         return (0);
263 }
264
265 /*
266  * Add a new hook
267  */
268 static int
269 ng_vjc_newhook(node_p node, hook_p hook, const char *name)
270 {
271         const priv_p priv = (priv_p) node->private;
272         hook_p *hookp;
273
274         /* Get hook */
275         if (strcmp(name, NG_VJC_HOOK_IP) == 0)
276                 hookp = &priv->ip;
277         else if (strcmp(name, NG_VJC_HOOK_VJCOMP) == 0)
278                 hookp = &priv->vjcomp;
279         else if (strcmp(name, NG_VJC_HOOK_VJUNCOMP) == 0)
280                 hookp = &priv->vjuncomp;
281         else if (strcmp(name, NG_VJC_HOOK_VJIP) == 0)
282                 hookp = &priv->vjip;
283         else
284                 return (EINVAL);
285
286         /* See if already connected */
287         if (*hookp)
288                 return (EISCONN);
289
290         /* OK */
291         *hookp = hook;
292         return (0);
293 }
294
295 /*
296  * Receive a control message
297  */
298 static int
299 ng_vjc_rcvmsg(node_p node, struct ng_mesg *msg,
300               const char *raddr, struct ng_mesg **rptr)
301 {
302         const priv_p priv = (priv_p) node->private;
303         struct ng_mesg *resp = NULL;
304         int error = 0;
305
306         /* Check type cookie */
307         switch (msg->header.typecookie) {
308         case NGM_VJC_COOKIE:
309                 switch (msg->header.cmd) {
310                 case NGM_VJC_SET_CONFIG:
311                     {
312                         struct ngm_vjc_config *const c =
313                                 (struct ngm_vjc_config *) msg->data;
314
315                         if (msg->header.arglen != sizeof(*c))
316                                 ERROUT(EINVAL);
317                         if ((priv->conf.enableComp || priv->conf.enableDecomp)
318                             && (c->enableComp || c->enableDecomp))
319                                 ERROUT(EALREADY);
320                         if (c->enableComp) {
321                                 if (c->maxChannel > NG_VJC_MAX_CHANNELS - 1
322                                     || c->maxChannel < NG_VJC_MIN_CHANNELS - 1)
323                                         ERROUT(EINVAL);
324                         } else
325                                 c->maxChannel = NG_VJC_MAX_CHANNELS - 1;
326                         if (c->enableComp != 0 || c->enableDecomp != 0) {
327                                 bzero(&priv->slc, sizeof(priv->slc));
328                                 sl_compress_init(&priv->slc, c->maxChannel);
329                         }
330                         priv->conf = *c;
331                         break;
332                     }
333                 case NGM_VJC_GET_CONFIG:
334                     {
335                         struct ngm_vjc_config *conf;
336
337                         NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT);
338                         if (resp == NULL)
339                                 ERROUT(ENOMEM);
340                         conf = (struct ngm_vjc_config *)resp->data;
341                         *conf = priv->conf;
342                         break;
343                     }
344                 case NGM_VJC_GET_STATE:
345                     {
346                         const struct slcompress *const sl0 = &priv->slc;
347                         struct slcompress *sl;
348                         u_int16_t index;
349                         int i;
350
351                         /* Get response structure */
352                         NG_MKRESPONSE(resp, msg, sizeof(*sl), M_NOWAIT);
353                         if (resp == NULL)
354                                 ERROUT(ENOMEM);
355                         sl = (struct slcompress *)resp->data;
356                         *sl = *sl0;
357
358                         /* Replace pointers with integer indicies */
359                         if (sl->last_cs != NULL) {
360                                 index = sl0->last_cs - sl0->tstate;
361                                 bzero(&sl->last_cs, sizeof(sl->last_cs));
362                                 *((u_int16_t *)&sl->last_cs) = index;
363                         }
364                         for (i = 0; i < MAX_STATES; i++) {
365                                 struct cstate *const cs = &sl->tstate[i];
366
367                                 index = sl0->tstate[i].cs_next - sl0->tstate;
368                                 bzero(&cs->cs_next, sizeof(cs->cs_next));
369                                 *((u_int16_t *)&cs->cs_next) = index;
370                         }
371                         break;
372                     }
373                 case NGM_VJC_CLR_STATS:
374                         priv->slc.sls_packets = 0;
375                         priv->slc.sls_compressed = 0;
376                         priv->slc.sls_searches = 0;
377                         priv->slc.sls_misses = 0;
378                         priv->slc.sls_uncompressedin = 0;
379                         priv->slc.sls_compressedin = 0;
380                         priv->slc.sls_errorin = 0;
381                         priv->slc.sls_tossed = 0;
382                         break;
383                 case NGM_VJC_RECV_ERROR:
384                         sl_uncompress_tcp(NULL, 0, TYPE_ERROR, &priv->slc);
385                         break;
386                 default:
387                         error = EINVAL;
388                         break;
389                 }
390                 break;
391         default:
392                 error = EINVAL;
393                 break;
394         }
395         if (rptr)
396                 *rptr = resp;
397         else if (resp)
398                 FREE(resp, M_NETGRAPH);
399
400 done:
401         FREE(msg, M_NETGRAPH);
402         return (error);
403 }
404
405 /*
406  * Receive data
407  */
408 static int
409 ng_vjc_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
410 {
411         const node_p node = hook->node;
412         const priv_p priv = (priv_p) node->private;
413         int error = 0;
414
415         if (hook == priv->ip) {                 /* outgoing packet */
416                 u_int type = TYPE_IP;
417
418                 /* Compress packet if enabled and proto is TCP */
419                 if (priv->conf.enableComp) {
420                         struct ip *ip;
421
422                         if ((m = ng_vjc_pulluphdrs(m, 0)) == NULL) {
423                                 NG_FREE_META(meta);
424                                 return (ENOBUFS);
425                         }
426                         ip = mtod(m, struct ip *);
427                         if (ip->ip_p == IPPROTO_TCP) {
428                                 const int origLen = m->m_len;
429
430                                 type = sl_compress_tcp(m, ip,
431                                     &priv->slc, priv->conf.compressCID);
432                                 m->m_pkthdr.len += m->m_len - origLen;
433                         }
434                 }
435
436                 /* Dispatch to the appropriate outgoing hook */
437                 switch (type) {
438                 case TYPE_IP:
439                         hook = priv->vjip;
440                         break;
441                 case TYPE_UNCOMPRESSED_TCP:
442                         hook = priv->vjuncomp;
443                         break;
444                 case TYPE_COMPRESSED_TCP:
445                         hook = priv->vjcomp;
446                         break;
447                 default:
448                         panic("%s: type=%d", __func__, type);
449                 }
450         } else if (hook == priv->vjcomp) {      /* incoming compressed packet */
451                 int vjlen, need2pullup;
452                 struct mbuf *hm;
453                 u_char *hdr;
454                 u_int hlen;
455
456                 /* Are we decompressing? */
457                 if (!priv->conf.enableDecomp) {
458                         NG_FREE_DATA(m, meta);
459                         return (ENXIO);
460                 }
461
462                 /* Pull up the necessary amount from the mbuf */
463                 need2pullup = MAX_VJHEADER;
464                 if (need2pullup > m->m_pkthdr.len)
465                         need2pullup = m->m_pkthdr.len;
466                 if (m->m_len < need2pullup
467                     && (m = m_pullup(m, need2pullup)) == NULL) {
468                         priv->slc.sls_errorin++;
469                         NG_FREE_META(meta);
470                         return (ENOBUFS);
471                 }
472
473                 /* Uncompress packet to reconstruct TCP/IP header */
474                 vjlen = sl_uncompress_tcp_core(mtod(m, u_char *),
475                     m->m_len, m->m_pkthdr.len, TYPE_COMPRESSED_TCP,
476                     &priv->slc, &hdr, &hlen);
477                 if (vjlen <= 0) {
478                         NG_FREE_DATA(m, meta);
479                         return (EINVAL);
480                 }
481                 m_adj(m, vjlen);
482
483                 /* Copy the reconstructed TCP/IP headers into a new mbuf */
484                 MGETHDR(hm, MB_DONTWAIT, MT_DATA);
485                 if (hm == NULL) {
486                         priv->slc.sls_errorin++;
487                         NG_FREE_DATA(m, meta);
488                         return (ENOBUFS);
489                 }
490                 hm->m_len = 0;
491                 hm->m_pkthdr.rcvif = NULL;
492                 if (hlen > MHLEN) {             /* unlikely, but can happen */
493                         MCLGET(hm, MB_DONTWAIT);
494                         if ((hm->m_flags & M_EXT) == 0) {
495                                 m_freem(hm);
496                                 priv->slc.sls_errorin++;
497                                 NG_FREE_DATA(m, meta);
498                                 return (ENOBUFS);
499                         }
500                 }
501                 bcopy(hdr, mtod(hm, u_char *), hlen);
502                 hm->m_len = hlen;
503
504                 /* Glue TCP/IP headers and rest of packet together */
505                 hm->m_next = m;
506                 hm->m_pkthdr.len = hlen + m->m_pkthdr.len;
507                 m = hm;
508                 hook = priv->ip;
509         } else if (hook == priv->vjuncomp) {    /* incoming uncompressed pkt */
510                 u_char *hdr;
511                 u_int hlen;
512
513                 /* Are we decompressing? */
514                 if (!priv->conf.enableDecomp) {
515                         NG_FREE_DATA(m, meta);
516                         return (ENXIO);
517                 }
518
519                 /* Pull up IP+TCP headers */
520                 if ((m = ng_vjc_pulluphdrs(m, 1)) == NULL) {
521                         NG_FREE_META(meta);
522                         return (ENOBUFS);
523                 }
524
525                 /* Run packet through uncompressor */
526                 if (sl_uncompress_tcp_core(mtod(m, u_char *),
527                     m->m_len, m->m_pkthdr.len, TYPE_UNCOMPRESSED_TCP,
528                     &priv->slc, &hdr, &hlen) < 0) {
529                         NG_FREE_DATA(m, meta);
530                         return (EINVAL);
531                 }
532                 hook = priv->ip;
533         } else if (hook == priv->vjip)  /* incoming regular packet (bypass) */
534                 hook = priv->ip;
535         else
536                 panic("%s: unknown hook", __func__);
537
538         /* Send result back out */
539         NG_SEND_DATA(error, hook, m, meta);
540         return (error);
541 }
542
543 /*
544  * Shutdown node
545  */
546 static int
547 ng_vjc_rmnode(node_p node)
548 {
549         const priv_p priv = (priv_p) node->private;
550
551         node->flags |= NG_INVALID;
552         ng_cutlinks(node);
553         ng_unname(node);
554         bzero(priv, sizeof(*priv));
555         FREE(priv, M_NETGRAPH);
556         node->private = NULL;
557         ng_unref(node);
558         return (0);
559 }
560
561 /*
562  * Hook disconnection
563  */
564 static int
565 ng_vjc_disconnect(hook_p hook)
566 {
567         const node_p node = hook->node;
568         const priv_p priv = node->private;
569
570         /* Zero out hook pointer */
571         if (hook == priv->ip)
572                 priv->ip = NULL;
573         else if (hook == priv->vjcomp)
574                 priv->vjcomp = NULL;
575         else if (hook == priv->vjuncomp)
576                 priv->vjuncomp = NULL;
577         else if (hook == priv->vjip)
578                 priv->vjip = NULL;
579         else
580                 panic("%s: unknown hook", __func__);
581
582         /* Go away if no hooks left */
583         if (node->numhooks == 0)
584                 ng_rmnode(node);
585         return (0);
586 }
587
588 /************************************************************************
589                         HELPER STUFF
590  ************************************************************************/
591
592 /*
593  * Pull up the full IP and TCP headers of a packet. If packet is not
594  * a TCP packet, just pull up the IP header.
595  */
596 static struct mbuf *
597 ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP)
598 {
599         struct ip *ip;
600         struct tcphdr *tcp;
601         int ihlen, thlen;
602
603         if (m->m_len < sizeof(*ip) && (m = m_pullup(m, sizeof(*ip))) == NULL)
604                 return (NULL);
605         ip = mtod(m, struct ip *);
606         if (!knownTCP && ip->ip_p != IPPROTO_TCP)
607                 return (m);
608         ihlen = ip->ip_hl << 2;
609         if (m->m_len < ihlen + sizeof(*tcp)) {
610                 if ((m = m_pullup(m, ihlen + sizeof(*tcp))) == NULL)
611                         return (NULL);
612                 ip = mtod(m, struct ip *);
613         }
614         tcp = (struct tcphdr *)((u_char *)ip + ihlen);
615         thlen = tcp->th_off << 2;
616         if (m->m_len < ihlen + thlen)
617                 m = m_pullup(m, ihlen + thlen);
618         return (m);
619 }
620