For kmalloc(), MALLOC() and contigmalloc(), use M_ZERO instead of
[dragonfly.git] / sys / netgraph / rfc1490 / ng_rfc1490.c
1
2 /*
3  * ng_rfc1490.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: Julian Elischer <julian@freebsd.org>
38  *
39  * $FreeBSD: src/sys/netgraph/ng_rfc1490.c,v 1.6.2.4 2002/07/02 22:17:18 archie Exp $
40  * $DragonFly: src/sys/netgraph/rfc1490/ng_rfc1490.c,v 1.6 2008/01/05 14:02:40 swildner Exp $
41  * $Whistle: ng_rfc1490.c,v 1.22 1999/11/01 09:24:52 julian Exp $
42  */
43
44 /*
45  * This node does RFC 1490 multiplexing.
46  *
47  * NOTE: RFC 1490 is updated by RFC 2427.
48  */
49
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/errno.h>
53 #include <sys/kernel.h>
54 #include <sys/malloc.h>
55 #include <sys/mbuf.h>
56 #include <sys/errno.h>
57 #include <sys/socket.h>
58
59 #include <net/if.h>
60 #include <netinet/in.h>
61 #include <netinet/if_ether.h>
62
63 #include <netgraph/ng_message.h>
64 #include <netgraph/netgraph.h>
65 #include "ng_rfc1490.h"
66
67 /*
68  * DEFINITIONS
69  */
70
71 /* Q.922 stuff -- see RFC 1490 */
72 #define HDLC_UI         0x03
73
74 #define NLPID_IP        0xCC
75 #define NLPID_PPP       0xCF
76 #define NLPID_SNAP      0x80
77 #define NLPID_Q933      0x08
78 #define NLPID_CLNP      0x81
79 #define NLPID_ESIS      0x82
80 #define NLPID_ISIS      0x83
81
82 /* Node private data */
83 struct ng_rfc1490_private {
84         hook_p  downlink;
85         hook_p  ppp;
86         hook_p  inet;
87 };
88 typedef struct ng_rfc1490_private *priv_p;
89
90 /* Netgraph node methods */
91 static ng_constructor_t ng_rfc1490_constructor;
92 static ng_rcvmsg_t      ng_rfc1490_rcvmsg;
93 static ng_shutdown_t    ng_rfc1490_rmnode;
94 static ng_newhook_t     ng_rfc1490_newhook;
95 static ng_rcvdata_t     ng_rfc1490_rcvdata;
96 static ng_disconnect_t  ng_rfc1490_disconnect;
97
98 /* Node type descriptor */
99 static struct ng_type typestruct = {
100         NG_VERSION,
101         NG_RFC1490_NODE_TYPE,
102         NULL,
103         ng_rfc1490_constructor,
104         ng_rfc1490_rcvmsg,
105         ng_rfc1490_rmnode,
106         ng_rfc1490_newhook,
107         NULL,
108         NULL,
109         ng_rfc1490_rcvdata,
110         ng_rfc1490_rcvdata,
111         ng_rfc1490_disconnect,
112         NULL
113 };
114 NETGRAPH_INIT(rfc1490, &typestruct);
115
116 /************************************************************************
117                         NETGRAPH NODE STUFF
118  ************************************************************************/
119
120 /*
121  * Node constructor
122  */
123 static int
124 ng_rfc1490_constructor(node_p *nodep)
125 {
126         priv_p priv;
127         int error;
128
129         /* Allocate private structure */
130         MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
131         if (priv == NULL)
132                 return (ENOMEM);
133
134         /* Call generic node constructor */
135         if ((error = ng_make_node_common(&typestruct, nodep))) {
136                 FREE(priv, M_NETGRAPH);
137                 return (error);
138         }
139         (*nodep)->private = priv;
140
141         /* Done */
142         return (0);
143 }
144
145 /*
146  * Give our ok for a hook to be added
147  */
148 static int
149 ng_rfc1490_newhook(node_p node, hook_p hook, const char *name)
150 {
151         const priv_p priv = node->private;
152
153         if (!strcmp(name, NG_RFC1490_HOOK_DOWNSTREAM)) {
154                 if (priv->downlink)
155                         return (EISCONN);
156                 priv->downlink = hook;
157         } else if (!strcmp(name, NG_RFC1490_HOOK_PPP)) {
158                 if (priv->ppp)
159                         return (EISCONN);
160                 priv->ppp = hook;
161         } else if (!strcmp(name, NG_RFC1490_HOOK_INET)) {
162                 if (priv->inet)
163                         return (EISCONN);
164                 priv->inet = hook;
165         } else
166                 return (EINVAL);
167         return (0);
168 }
169
170 /*
171  * Receive a control message. We don't support any special ones.
172  */
173 static int
174 ng_rfc1490_rcvmsg(node_p node, struct ng_mesg *msg,
175                   const char *raddr, struct ng_mesg **rp)
176 {
177         FREE(msg, M_NETGRAPH);
178         return (EINVAL);
179 }
180
181 /*
182  * Receive data on a hook and encapsulate according to RFC 1490.
183  * Only those nodes marked (*) are supported by this routine so far.
184  *
185  *                            Q.922 control
186  *                                 |
187  *                                 |
188  *            --------------------------------------------
189  *            | 0x03                                     |
190  *           UI                                       I Frame
191  *            |                                          |
192  *      ---------------------------------         --------------
193  *      | 0x08  | 0x81  |0xCC   |0xCF   | 0x00    |..01....    |..10....
194  *      |       |       |       |       | 0x80    |            |
195  *     Q.933   CLNP    IP(*)   PPP(*)  SNAP     ISO 8208    ISO 8208
196  *      |                    (rfc1973)  |       Modulo 8    Modulo 128
197  *      |                               |
198  *      --------------------           OUI
199  *      |                  |            |
200  *     L2 ID              L3 ID      -------------------------
201  *      |               User         |00-80-C2               |00-00-00
202  *      |               specified    |                       |
203  *      |               0x70        PID                     Ethertype
204  *      |                            |                       |
205  *      -------------------        --------------...        ----------
206  *      |0x51 |0x4E |     |0x4C    |0x1   |0xB  |           |0x806   |
207  *      |     |     |     |        |      |     |           |        |
208  *     7776  Q.922 Others 802.2   802.3  802.6 Others       ARP(*)  Others
209  *
210  *
211  */
212
213 #define MAX_ENCAPS_HDR  8
214 #define ERROUT(x)       do { error = (x); goto done; } while (0)
215 #define OUICMP(P,A,B,C) ((P)[0]==(A) && (P)[1]==(B) && (P)[2]==(C))
216
217 static int
218 ng_rfc1490_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
219 {
220         const node_p node = hook->node;
221         const priv_p priv = node->private;
222         int error = 0;
223
224         if (hook == priv->downlink) {
225                 const u_char *start;
226                 const u_char *ptr;
227
228                 if (!m || (m->m_len < MAX_ENCAPS_HDR
229                     && !(m = m_pullup(m, MAX_ENCAPS_HDR))))
230                         ERROUT(ENOBUFS);
231                 ptr = start = mtod(m, const u_char *);
232
233                 /* Must be UI frame */
234                 if (*ptr++ != HDLC_UI)
235                         ERROUT(0);
236
237                 /* Eat optional zero pad byte */
238                 if (*ptr == 0x00)
239                         ptr++;
240
241                 /* Multiplex on NLPID */
242                 switch (*ptr++) {
243                 case NLPID_SNAP:
244                         if (OUICMP(ptr, 0, 0, 0)) {     /* It's an ethertype */
245                                 u_int16_t etype;
246
247                                 ptr += 3;
248                                 etype = ntohs(*((const u_int16_t *)ptr));
249                                 ptr += 2;
250                                 m_adj(m, ptr - start);
251                                 switch (etype) {
252                                 case ETHERTYPE_IP:
253                                         NG_SEND_DATA(error,
254                                             priv->inet, m, meta);
255                                         break;
256                                 case ETHERTYPE_ARP:
257                                 case ETHERTYPE_REVARP:
258                                 default:
259                                         ERROUT(0);
260                                 }
261                         } else if (OUICMP(ptr, 0x00, 0x80, 0xc2))       /* 802.1 bridging */
262                                 ERROUT(0);
263                         else    /* Other weird stuff... */
264                                 ERROUT(0);
265                         break;
266                 case NLPID_IP:
267                         m_adj(m, ptr - start);
268                         NG_SEND_DATA(error, priv->inet, m, meta);
269                         break;
270                 case NLPID_PPP:
271                         m_adj(m, ptr - start);
272                         NG_SEND_DATA(error, priv->ppp, m, meta);
273                         break;
274                 case NLPID_Q933:
275                 case NLPID_CLNP:
276                 case NLPID_ESIS:
277                 case NLPID_ISIS:
278                         ERROUT(0);
279                 default:        /* Try PPP (see RFC 1973) */
280                         ptr--;  /* NLPID becomes PPP proto */
281                         if ((*ptr & 0x01) == 0x01)
282                                 ERROUT(0);
283                         m_adj(m, ptr - start);
284                         NG_SEND_DATA(error, priv->ppp, m, meta);
285                         break;
286                 }
287         } else if (hook == priv->ppp) {
288                 M_PREPEND(m, 2, MB_DONTWAIT);   /* Prepend PPP NLPID */
289                 if (!m)
290                         ERROUT(ENOBUFS);
291                 mtod(m, u_char *)[0] = HDLC_UI;
292                 mtod(m, u_char *)[1] = NLPID_PPP;
293                 NG_SEND_DATA(error, priv->downlink, m, meta);
294         } else if (hook == priv->inet) {
295                 M_PREPEND(m, 2, MB_DONTWAIT);   /* Prepend IP NLPID */
296                 if (!m)
297                         ERROUT(ENOBUFS);
298                 mtod(m, u_char *)[0] = HDLC_UI;
299                 mtod(m, u_char *)[1] = NLPID_IP;
300                 NG_SEND_DATA(error, priv->downlink, m, meta);
301         } else
302                 panic(__func__);
303
304 done:
305         NG_FREE_DATA(m, meta);
306         return (error);
307 }
308
309 /*
310  * Nuke node
311  */
312 static int
313 ng_rfc1490_rmnode(node_p node)
314 {
315         const priv_p priv = node->private;
316
317         /* Take down netgraph node */
318         node->flags |= NG_INVALID;
319         ng_cutlinks(node);
320         ng_unname(node);
321         bzero(priv, sizeof(*priv));
322         node->private = NULL;
323         FREE(priv, M_NETGRAPH);
324         ng_unref(node);         /* let the node escape */
325         return (0);
326 }
327
328 /*
329  * Hook disconnection
330  */
331 static int
332 ng_rfc1490_disconnect(hook_p hook)
333 {
334         const priv_p priv = hook->node->private;
335
336         if (hook->node->numhooks == 0)
337                 ng_rmnode(hook->node);
338         else if (hook == priv->downlink)
339                 priv->downlink = NULL;
340         else if (hook == priv->inet)
341                 priv->inet = NULL;
342         else if (hook == priv->ppp)
343                 priv->ppp = NULL;
344         else
345                 panic(__func__);
346         return (0);
347 }
348