xref: /freebsd/usr.sbin/ppp/link.c (revision 6ae1554a5d9b318f8ad53ccc39fa5a961403da73) 
1 /*-
2  * Copyright (c) 1998 Brian Somers <brian@Awfulhak.org>
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, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  *
28  */
29 
30 #include <sys/types.h>
31 #include <netinet/in_systm.h>
32 #include <sys/socket.h>
33 #include <sys/un.h>
34 #include <netinet/in.h>
35 #include <netinet/ip.h>
36 
37 #include <stdarg.h>
38 #include <stdio.h>
39 #include <string.h>
40 #include <termios.h>
41 
42 #include "defs.h"
43 #include "layer.h"
44 #include "mbuf.h"
45 #include "log.h"
46 #include "timer.h"
47 #include "lqr.h"
48 #include "hdlc.h"
49 #include "throughput.h"
50 #include "proto.h"
51 #include "fsm.h"
52 #include "descriptor.h"
53 #include "lcp.h"
54 #include "ccp.h"
55 #include "link.h"
56 #include "prompt.h"
57 #include "async.h"
58 #include "physical.h"
59 #include "mp.h"
60 #include "iplist.h"
61 #include "slcompress.h"
62 #include "ncpaddr.h"
63 #include "ip.h"
64 #include "ipcp.h"
65 #include "ipv6cp.h"
66 #include "auth.h"
67 #include "pap.h"
68 #include "chap.h"
69 #include "cbcp.h"
70 #include "command.h"
71 
72 static void Despatch(struct bundle *, struct link *, struct mbuf *, u_short);
73 
74 static inline void
75 link_AddInOctets(struct link *l, int n)
76 {
77   if (l->stats.gather) {
78     throughput_addin(&l->stats.total, n);
79     if (l->stats.parent)
80       throughput_addin(l->stats.parent, n);
81   }
82 }
83 
84 static inline void
85 link_AddOutOctets(struct link *l, int n)
86 {
87   if (l->stats.gather) {
88     throughput_addout(&l->stats.total, n);
89     if (l->stats.parent)
90       throughput_addout(l->stats.parent, n);
91   }
92 }
93 
94 void
95 link_SequenceQueue(struct link *l)
96 {
97   struct mqueue *queue, *highest;
98 
99   log_Printf(LogDEBUG, "link_SequenceQueue\n");
100 
101   highest = LINK_HIGHQ(l);
102   for (queue = l->Queue; queue < highest; queue++)
103     while (queue->len)
104       m_enqueue(highest, m_dequeue(queue));
105 }
106 
107 void
108 link_DeleteQueue(struct link *l)
109 {
110   struct mqueue *queue, *highest;
111 
112   highest = LINK_HIGHQ(l);
113   for (queue = l->Queue; queue <= highest; queue++)
114     while (queue->top)
115       m_freem(m_dequeue(queue));
116 }
117 
118 size_t
119 link_QueueLen(struct link *l)
120 {
121   unsigned i;
122   size_t len;
123 
124   for (i = 0, len = 0; i < LINK_QUEUES(l); i++)
125     len += l->Queue[i].len;
126 
127   return len;
128 }
129 
130 size_t
131 link_QueueBytes(struct link *l)
132 {
133   unsigned i;
134   size_t len, bytes;
135   struct mbuf *m;
136 
137   bytes = 0;
138   for (i = 0, len = 0; i < LINK_QUEUES(l); i++) {
139     len = l->Queue[i].len;
140     m = l->Queue[i].top;
141     while (len--) {
142       bytes += m_length(m);
143       m = m->m_nextpkt;
144     }
145   }
146 
147   return bytes;
148 }
149 
150 void
151 link_PendingLowPriorityData(struct link *l, size_t *pkts, size_t *octets)
152 {
153   struct mqueue *queue, *highest;
154   struct mbuf *m;
155   size_t len;
156 
157   /*
158    * This is all rfc1989 stuff... because our LQR packet is going to bypass
159    * everything that's not in the highest priority queue, we must be able to
160    * subtract that data from our outgoing packet/octet counts.  However,
161    * we've already async-encoded our data at this point, but the async
162    * encodings MUSTn't be a part of the LQR-reported payload :(  So, we have
163    * the async layer record how much it's padded the packet in the mbuf's
164    * priv field, and when we calculate our outgoing LQR values we subtract
165    * this value for each packet from the octet count sent.
166    */
167 
168   highest = LINK_HIGHQ(l);
169   *pkts = *octets = 0;
170   for (queue = l->Queue; queue < highest; queue++) {
171     len = queue->len;
172     *pkts += len;
173     for (m = queue->top; len--; m = m->m_nextpkt)
174       *octets += m_length(m) - m->priv;
175   }
176 }
177 
178 struct mbuf *
179 link_Dequeue(struct link *l)
180 {
181   int pri;
182   struct mbuf *bp;
183 
184   for (bp = NULL, pri = LINK_QUEUES(l) - 1; pri >= 0; pri--)
185     if (l->Queue[pri].len) {
186       bp = m_dequeue(l->Queue + pri);
187       log_Printf(LogDEBUG, "link_Dequeue: Dequeued from queue %d,"
188                 " containing %lu more packets\n", pri,
189                 (u_long)l->Queue[pri].len);
190       break;
191     }
192 
193   return bp;
194 }
195 
196 static struct protostatheader {
197   u_short number;
198   const char *name;
199 } ProtocolStat[NPROTOSTAT] = {
200   { PROTO_IP, "IP" },
201   { PROTO_VJUNCOMP, "VJ_UNCOMP" },
202   { PROTO_VJCOMP, "VJ_COMP" },
203   { PROTO_COMPD, "COMPD" },
204   { PROTO_ICOMPD, "ICOMPD" },
205   { PROTO_LCP, "LCP" },
206   { PROTO_IPCP, "IPCP" },
207   { PROTO_CCP, "CCP" },
208   { PROTO_PAP, "PAP" },
209   { PROTO_LQR, "LQR" },
210   { PROTO_CHAP, "CHAP" },
211   { PROTO_MP, "MULTILINK" },
212   { 0, "Others" }
213 };
214 
215 void
216 link_ProtocolRecord(struct link *l, u_short proto, int type)
217 {
218   int i;
219 
220   for (i = 0; i < NPROTOSTAT; i++)
221     if (ProtocolStat[i].number == proto)
222       break;
223 
224   if (type == PROTO_IN)
225     l->proto_in[i]++;
226   else
227     l->proto_out[i]++;
228 }
229 
230 void
231 link_ReportProtocolStatus(struct link *l, struct prompt *prompt)
232 {
233   int i;
234 
235   prompt_Printf(prompt, "    Protocol     in        out      "
236                 "Protocol      in       out\n");
237   for (i = 0; i < NPROTOSTAT; i++) {
238     prompt_Printf(prompt, "   %-9s: %8lu, %8lu",
239 	    ProtocolStat[i].name, l->proto_in[i], l->proto_out[i]);
240     if ((i % 2) == 0)
241       prompt_Printf(prompt, "\n");
242   }
243   if (!(i % 2))
244     prompt_Printf(prompt, "\n");
245 }
246 
247 void
248 link_PushPacket(struct link *l, struct mbuf *bp, struct bundle *b, int pri,
249                 u_short proto)
250 {
251   int layer;
252 
253   /*
254    * When we ``push'' a packet into the link, it gets processed by the
255    * ``push'' function in each layer starting at the top.
256    * We never expect the result of a ``push'' to be more than one
257    * packet (as we do with ``pull''s).
258    */
259 
260   if(pri < 0 || (unsigned)pri >= LINK_QUEUES(l))
261     pri = 0;
262 
263   bp->priv = 0;		/* Adjusted by the async layer ! */
264   for (layer = l->nlayers; layer && bp; layer--)
265     if (l->layer[layer - 1]->push != NULL)
266       bp = (*l->layer[layer - 1]->push)(b, l, bp, pri, &proto);
267 
268   if (bp) {
269     link_AddOutOctets(l, m_length(bp));
270     log_Printf(LogDEBUG, "link_PushPacket: Transmit proto 0x%04x\n", proto);
271     m_enqueue(l->Queue + pri, m_pullup(bp));
272   }
273 }
274 
275 void
276 link_PullPacket(struct link *l, char *buf, size_t len, struct bundle *b)
277 {
278   struct mbuf *bp, *lbp[LAYER_MAX], *next;
279   u_short lproto[LAYER_MAX], proto;
280   int layer;
281 
282   /*
283    * When we ``pull'' a packet from the link, it gets processed by the
284    * ``pull'' function in each layer starting at the bottom.
285    * Each ``pull'' may produce multiple packets, chained together using
286    * bp->m_nextpkt.
287    * Each packet that results from each pull has to be pulled through
288    * all of the higher layers before the next resulting packet is pulled
289    * through anything; this ensures that packets that depend on the
290    * fsm state resulting from the receipt of the previous packet aren't
291    * surprised.
292    */
293 
294   link_AddInOctets(l, len);
295 
296   memset(lbp, '\0', sizeof lbp);
297   lbp[0] = m_get(len, MB_UNKNOWN);
298   memcpy(MBUF_CTOP(lbp[0]), buf, len);
299   lproto[0] = 0;
300   layer = 0;
301 
302   while (layer || lbp[layer]) {
303     if (lbp[layer] == NULL) {
304       layer--;
305       continue;
306     }
307     bp = lbp[layer];
308     lbp[layer] = bp->m_nextpkt;
309     bp->m_nextpkt = NULL;
310     proto = lproto[layer];
311 
312     if (l->layer[layer]->pull != NULL)
313       bp = (*l->layer[layer]->pull)(b, l, bp, &proto);
314 
315     if (layer == l->nlayers - 1) {
316       /* We've just done the top layer, despatch the packet(s) */
317       while (bp) {
318         next = bp->m_nextpkt;
319         bp->m_nextpkt = NULL;
320         log_Printf(LogDEBUG, "link_PullPacket: Despatch proto 0x%04x\n", proto);
321         Despatch(b, l, bp, proto);
322         bp = next;
323       }
324     } else {
325       lbp[++layer] = bp;
326       lproto[layer] = proto;
327     }
328   }
329 }
330 
331 int
332 link_Stack(struct link *l, struct layer *layer)
333 {
334   if (l->nlayers == sizeof l->layer / sizeof l->layer[0]) {
335     log_Printf(LogERROR, "%s: Oops, cannot stack a %s layer...\n",
336                l->name, layer->name);
337     return 0;
338   }
339   l->layer[l->nlayers++] = layer;
340   return 1;
341 }
342 
343 void
344 link_EmptyStack(struct link *l)
345 {
346   l->nlayers = 0;
347 }
348 
349 static const struct {
350   u_short proto;
351   struct mbuf *(*fn)(struct bundle *, struct link *, struct mbuf *);
352 } despatcher[] = {
353   { PROTO_IP, ipv4_Input },
354 #ifndef NOINET6
355   { PROTO_IPV6, ipv6_Input },
356 #endif
357   { PROTO_MP, mp_Input },
358   { PROTO_LCP, lcp_Input },
359   { PROTO_IPCP, ipcp_Input },
360 #ifndef NOINET6
361   { PROTO_IPV6CP, ipv6cp_Input },
362 #endif
363   { PROTO_PAP, pap_Input },
364   { PROTO_CHAP, chap_Input },
365   { PROTO_CCP, ccp_Input },
366   { PROTO_LQR, lqr_Input },
367   { PROTO_CBCP, cbcp_Input }
368 };
369 
370 #define DSIZE (sizeof despatcher / sizeof despatcher[0])
371 
372 static void
373 Despatch(struct bundle *bundle, struct link *l, struct mbuf *bp, u_short proto)
374 {
375   unsigned f;
376 
377   for (f = 0; f < DSIZE; f++)
378     if (despatcher[f].proto == proto) {
379       bp = (*despatcher[f].fn)(bundle, l, bp);
380       break;
381     }
382 
383   if (bp) {
384     struct physical *p = link2physical(l);
385 
386     log_Printf(LogPHASE, "%s protocol 0x%04x (%s)\n",
387                f == DSIZE ? "Unknown" : "Unexpected", proto,
388                hdlc_Protocol2Nam(proto));
389     bp = m_pullup(proto_Prepend(bp, proto, 0, 0));
390     lcp_SendProtoRej(&l->lcp, MBUF_CTOP(bp), bp->m_len);
391     if (p) {
392       p->hdlc.lqm.ifInDiscards++;
393       p->hdlc.stats.unknownproto++;
394     }
395     m_freem(bp);
396   }
397 }
398 
399 int
400 link_ShowLayers(struct cmdargs const *arg)
401 {
402   struct link *l = command_ChooseLink(arg);
403   int layer;
404 
405   for (layer = l->nlayers; layer; layer--)
406     prompt_Printf(arg->prompt, "%s%s", layer == l->nlayers ? "" : ", ",
407                   l->layer[layer - 1]->name);
408   if (l->nlayers)
409     prompt_Printf(arg->prompt, "\n");
410 
411   return 0;
412 }
413