1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Generic HDLC support routines for Linux |
4 | * Point-to-point protocol support |
5 | * |
6 | * Copyright (C) 1999 - 2008 Krzysztof Halasa <khc@pm.waw.pl> |
7 | */ |
8 | |
9 | #include <linux/errno.h> |
10 | #include <linux/hdlc.h> |
11 | #include <linux/if_arp.h> |
12 | #include <linux/inetdevice.h> |
13 | #include <linux/init.h> |
14 | #include <linux/kernel.h> |
15 | #include <linux/module.h> |
16 | #include <linux/pkt_sched.h> |
17 | #include <linux/poll.h> |
18 | #include <linux/skbuff.h> |
19 | #include <linux/slab.h> |
20 | #include <linux/spinlock.h> |
21 | |
22 | #define DEBUG_CP 0 /* also bytes# to dump */ |
23 | #define DEBUG_STATE 0 |
24 | #define 0 |
25 | |
26 | #define HDLC_ADDR_ALLSTATIONS 0xFF |
27 | #define HDLC_CTRL_UI 0x03 |
28 | |
29 | #define PID_LCP 0xC021 |
30 | #define PID_IP 0x0021 |
31 | #define PID_IPCP 0x8021 |
32 | #define PID_IPV6 0x0057 |
33 | #define PID_IPV6CP 0x8057 |
34 | |
35 | enum {IDX_LCP = 0, IDX_IPCP, IDX_IPV6CP, IDX_COUNT}; |
36 | enum {CP_CONF_REQ = 1, CP_CONF_ACK, CP_CONF_NAK, CP_CONF_REJ, CP_TERM_REQ, |
37 | CP_TERM_ACK, CP_CODE_REJ, LCP_PROTO_REJ, LCP_ECHO_REQ, LCP_ECHO_REPLY, |
38 | LCP_DISC_REQ, CP_CODES}; |
39 | #if DEBUG_CP |
40 | static const char *const code_names[CP_CODES] = { |
41 | "0" , "ConfReq" , "ConfAck" , "ConfNak" , "ConfRej" , "TermReq" , |
42 | "TermAck" , "CodeRej" , "ProtoRej" , "EchoReq" , "EchoReply" , "Discard" |
43 | }; |
44 | |
45 | static char debug_buffer[64 + 3 * DEBUG_CP]; |
46 | #endif |
47 | |
48 | enum {LCP_OPTION_MRU = 1, LCP_OPTION_ACCM, LCP_OPTION_MAGIC = 5}; |
49 | |
50 | struct { |
51 | u8 ; |
52 | u8 ; |
53 | __be16 ; |
54 | }; |
55 | |
56 | struct { |
57 | u8 ; |
58 | u8 ; |
59 | __be16 ; |
60 | }; |
61 | |
62 | struct proto { |
63 | struct net_device *dev; |
64 | struct timer_list timer; |
65 | unsigned long timeout; |
66 | u16 pid; /* protocol ID */ |
67 | u8 state; |
68 | u8 cr_id; /* ID of last Configuration-Request */ |
69 | u8 restart_counter; |
70 | }; |
71 | |
72 | struct ppp { |
73 | struct proto protos[IDX_COUNT]; |
74 | spinlock_t lock; |
75 | unsigned long last_pong; |
76 | unsigned int req_timeout, cr_retries, term_retries; |
77 | unsigned int keepalive_interval, keepalive_timeout; |
78 | u8 seq; /* local sequence number for requests */ |
79 | u8 echo_id; /* ID of last Echo-Request (LCP) */ |
80 | }; |
81 | |
82 | enum {CLOSED = 0, STOPPED, STOPPING, REQ_SENT, ACK_RECV, ACK_SENT, OPENED, |
83 | STATES, STATE_MASK = 0xF}; |
84 | enum {START = 0, STOP, TO_GOOD, TO_BAD, RCR_GOOD, RCR_BAD, RCA, RCN, RTR, RTA, |
85 | RUC, RXJ_GOOD, RXJ_BAD, EVENTS}; |
86 | enum {INV = 0x10, IRC = 0x20, ZRC = 0x40, SCR = 0x80, SCA = 0x100, |
87 | SCN = 0x200, STR = 0x400, STA = 0x800, SCJ = 0x1000}; |
88 | |
89 | #if DEBUG_STATE |
90 | static const char *const state_names[STATES] = { |
91 | "Closed" , "Stopped" , "Stopping" , "ReqSent" , "AckRecv" , "AckSent" , |
92 | "Opened" |
93 | }; |
94 | |
95 | static const char *const event_names[EVENTS] = { |
96 | "Start" , "Stop" , "TO+" , "TO-" , "RCR+" , "RCR-" , "RCA" , "RCN" , |
97 | "RTR" , "RTA" , "RUC" , "RXJ+" , "RXJ-" |
98 | }; |
99 | #endif |
100 | |
101 | static struct sk_buff_head tx_queue; /* used when holding the spin lock */ |
102 | |
103 | static int ppp_ioctl(struct net_device *dev, struct if_settings *ifs); |
104 | |
105 | static inline struct ppp *get_ppp(struct net_device *dev) |
106 | { |
107 | return (struct ppp *)dev_to_hdlc(dev)->state; |
108 | } |
109 | |
110 | static inline struct proto *get_proto(struct net_device *dev, u16 pid) |
111 | { |
112 | struct ppp *ppp = get_ppp(dev); |
113 | |
114 | switch (pid) { |
115 | case PID_LCP: |
116 | return &ppp->protos[IDX_LCP]; |
117 | case PID_IPCP: |
118 | return &ppp->protos[IDX_IPCP]; |
119 | case PID_IPV6CP: |
120 | return &ppp->protos[IDX_IPV6CP]; |
121 | default: |
122 | return NULL; |
123 | } |
124 | } |
125 | |
126 | static inline const char *proto_name(u16 pid) |
127 | { |
128 | switch (pid) { |
129 | case PID_LCP: |
130 | return "LCP" ; |
131 | case PID_IPCP: |
132 | return "IPCP" ; |
133 | case PID_IPV6CP: |
134 | return "IPV6CP" ; |
135 | default: |
136 | return NULL; |
137 | } |
138 | } |
139 | |
140 | static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev) |
141 | { |
142 | struct hdlc_header *data = (struct hdlc_header *)skb->data; |
143 | |
144 | if (skb->len < sizeof(struct hdlc_header)) |
145 | return htons(ETH_P_HDLC); |
146 | if (data->address != HDLC_ADDR_ALLSTATIONS || |
147 | data->control != HDLC_CTRL_UI) |
148 | return htons(ETH_P_HDLC); |
149 | |
150 | switch (data->protocol) { |
151 | case cpu_to_be16(PID_IP): |
152 | skb_pull(skb, len: sizeof(struct hdlc_header)); |
153 | return htons(ETH_P_IP); |
154 | |
155 | case cpu_to_be16(PID_IPV6): |
156 | skb_pull(skb, len: sizeof(struct hdlc_header)); |
157 | return htons(ETH_P_IPV6); |
158 | |
159 | default: |
160 | return htons(ETH_P_HDLC); |
161 | } |
162 | } |
163 | |
164 | static int (struct sk_buff *skb, struct net_device *dev, |
165 | u16 type, const void *daddr, const void *saddr, |
166 | unsigned int len) |
167 | { |
168 | struct hdlc_header *data; |
169 | #if DEBUG_HARD_HEADER |
170 | printk(KERN_DEBUG "%s: ppp_hard_header() called\n" , dev->name); |
171 | #endif |
172 | |
173 | skb_push(skb, len: sizeof(struct hdlc_header)); |
174 | data = (struct hdlc_header *)skb->data; |
175 | |
176 | data->address = HDLC_ADDR_ALLSTATIONS; |
177 | data->control = HDLC_CTRL_UI; |
178 | switch (type) { |
179 | case ETH_P_IP: |
180 | data->protocol = htons(PID_IP); |
181 | break; |
182 | case ETH_P_IPV6: |
183 | data->protocol = htons(PID_IPV6); |
184 | break; |
185 | case PID_LCP: |
186 | case PID_IPCP: |
187 | case PID_IPV6CP: |
188 | data->protocol = htons(type); |
189 | break; |
190 | default: /* unknown protocol */ |
191 | data->protocol = 0; |
192 | } |
193 | return sizeof(struct hdlc_header); |
194 | } |
195 | |
196 | static void ppp_tx_flush(void) |
197 | { |
198 | struct sk_buff *skb; |
199 | |
200 | while ((skb = skb_dequeue(list: &tx_queue)) != NULL) |
201 | dev_queue_xmit(skb); |
202 | } |
203 | |
204 | static void ppp_tx_cp(struct net_device *dev, u16 pid, u8 code, |
205 | u8 id, unsigned int len, const void *data) |
206 | { |
207 | struct sk_buff *skb; |
208 | struct cp_header *cp; |
209 | unsigned int magic_len = 0; |
210 | static u32 magic; |
211 | |
212 | #if DEBUG_CP |
213 | int i; |
214 | char *ptr; |
215 | #endif |
216 | |
217 | if (pid == PID_LCP && (code == LCP_ECHO_REQ || code == LCP_ECHO_REPLY)) |
218 | magic_len = sizeof(magic); |
219 | |
220 | skb = dev_alloc_skb(length: sizeof(struct hdlc_header) + |
221 | sizeof(struct cp_header) + magic_len + len); |
222 | if (!skb) |
223 | return; |
224 | |
225 | skb_reserve(skb, len: sizeof(struct hdlc_header)); |
226 | |
227 | cp = skb_put(skb, len: sizeof(struct cp_header)); |
228 | cp->code = code; |
229 | cp->id = id; |
230 | cp->len = htons(sizeof(struct cp_header) + magic_len + len); |
231 | |
232 | if (magic_len) |
233 | skb_put_data(skb, data: &magic, len: magic_len); |
234 | if (len) |
235 | skb_put_data(skb, data, len); |
236 | |
237 | #if DEBUG_CP |
238 | BUG_ON(code >= CP_CODES); |
239 | ptr = debug_buffer; |
240 | *ptr = '\x0'; |
241 | for (i = 0; i < min_t(unsigned int, magic_len + len, DEBUG_CP); i++) { |
242 | sprintf(ptr, " %02X" , skb->data[sizeof(struct cp_header) + i]); |
243 | ptr += strlen(ptr); |
244 | } |
245 | printk(KERN_DEBUG "%s: TX %s [%s id 0x%X]%s\n" , dev->name, |
246 | proto_name(pid), code_names[code], id, debug_buffer); |
247 | #endif |
248 | |
249 | ppp_hard_header(skb, dev, type: pid, NULL, NULL, len: 0); |
250 | |
251 | skb->priority = TC_PRIO_CONTROL; |
252 | skb->dev = dev; |
253 | skb->protocol = htons(ETH_P_HDLC); |
254 | skb_reset_network_header(skb); |
255 | skb_queue_tail(list: &tx_queue, newsk: skb); |
256 | } |
257 | |
258 | /* State transition table (compare STD-51) |
259 | Events Actions |
260 | TO+ = Timeout with counter > 0 irc = Initialize-Restart-Count |
261 | TO- = Timeout with counter expired zrc = Zero-Restart-Count |
262 | |
263 | RCR+ = Receive-Configure-Request (Good) scr = Send-Configure-Request |
264 | RCR- = Receive-Configure-Request (Bad) |
265 | RCA = Receive-Configure-Ack sca = Send-Configure-Ack |
266 | RCN = Receive-Configure-Nak/Rej scn = Send-Configure-Nak/Rej |
267 | |
268 | RTR = Receive-Terminate-Request str = Send-Terminate-Request |
269 | RTA = Receive-Terminate-Ack sta = Send-Terminate-Ack |
270 | |
271 | RUC = Receive-Unknown-Code scj = Send-Code-Reject |
272 | RXJ+ = Receive-Code-Reject (permitted) |
273 | or Receive-Protocol-Reject |
274 | RXJ- = Receive-Code-Reject (catastrophic) |
275 | or Receive-Protocol-Reject |
276 | */ |
277 | static int cp_table[EVENTS][STATES] = { |
278 | /* CLOSED STOPPED STOPPING REQ_SENT ACK_RECV ACK_SENT OPENED |
279 | 0 1 2 3 4 5 6 */ |
280 | {IRC|SCR|3, INV , INV , INV , INV , INV , INV }, /* START */ |
281 | { INV , 0 , 0 , 0 , 0 , 0 , 0 }, /* STOP */ |
282 | { INV , INV ,STR|2, SCR|3 ,SCR|3, SCR|5 , INV }, /* TO+ */ |
283 | { INV , INV , 1 , 1 , 1 , 1 , INV }, /* TO- */ |
284 | { STA|0 ,IRC|SCR|SCA|5, 2 , SCA|5 ,SCA|6, SCA|5 ,SCR|SCA|5}, /* RCR+ */ |
285 | { STA|0 ,IRC|SCR|SCN|3, 2 , SCN|3 ,SCN|4, SCN|3 ,SCR|SCN|3}, /* RCR- */ |
286 | { STA|0 , STA|1 , 2 , IRC|4 ,SCR|3, 6 , SCR|3 }, /* RCA */ |
287 | { STA|0 , STA|1 , 2 ,IRC|SCR|3,SCR|3,IRC|SCR|5, SCR|3 }, /* RCN */ |
288 | { STA|0 , STA|1 ,STA|2, STA|3 ,STA|3, STA|3 ,ZRC|STA|2}, /* RTR */ |
289 | { 0 , 1 , 1 , 3 , 3 , 5 , SCR|3 }, /* RTA */ |
290 | { SCJ|0 , SCJ|1 ,SCJ|2, SCJ|3 ,SCJ|4, SCJ|5 , SCJ|6 }, /* RUC */ |
291 | { 0 , 1 , 2 , 3 , 3 , 5 , 6 }, /* RXJ+ */ |
292 | { 0 , 1 , 1 , 1 , 1 , 1 ,IRC|STR|2}, /* RXJ- */ |
293 | }; |
294 | |
295 | /* SCA: RCR+ must supply id, len and data |
296 | SCN: RCR- must supply code, id, len and data |
297 | STA: RTR must supply id |
298 | SCJ: RUC must supply CP packet len and data */ |
299 | static void ppp_cp_event(struct net_device *dev, u16 pid, u16 event, u8 code, |
300 | u8 id, unsigned int len, const void *data) |
301 | { |
302 | int old_state, action; |
303 | struct ppp *ppp = get_ppp(dev); |
304 | struct proto *proto = get_proto(dev, pid); |
305 | |
306 | old_state = proto->state; |
307 | BUG_ON(old_state >= STATES); |
308 | BUG_ON(event >= EVENTS); |
309 | |
310 | #if DEBUG_STATE |
311 | printk(KERN_DEBUG "%s: %s ppp_cp_event(%s) %s ...\n" , dev->name, |
312 | proto_name(pid), event_names[event], state_names[proto->state]); |
313 | #endif |
314 | |
315 | action = cp_table[event][old_state]; |
316 | |
317 | proto->state = action & STATE_MASK; |
318 | if (action & (SCR | STR)) /* set Configure-Req/Terminate-Req timer */ |
319 | mod_timer(timer: &proto->timer, expires: proto->timeout = |
320 | jiffies + ppp->req_timeout * HZ); |
321 | if (action & ZRC) |
322 | proto->restart_counter = 0; |
323 | if (action & IRC) |
324 | proto->restart_counter = (proto->state == STOPPING) ? |
325 | ppp->term_retries : ppp->cr_retries; |
326 | |
327 | if (action & SCR) /* send Configure-Request */ |
328 | ppp_tx_cp(dev, pid, code: CP_CONF_REQ, id: proto->cr_id = ++ppp->seq, |
329 | len: 0, NULL); |
330 | if (action & SCA) /* send Configure-Ack */ |
331 | ppp_tx_cp(dev, pid, code: CP_CONF_ACK, id, len, data); |
332 | if (action & SCN) /* send Configure-Nak/Reject */ |
333 | ppp_tx_cp(dev, pid, code, id, len, data); |
334 | if (action & STR) /* send Terminate-Request */ |
335 | ppp_tx_cp(dev, pid, code: CP_TERM_REQ, id: ++ppp->seq, len: 0, NULL); |
336 | if (action & STA) /* send Terminate-Ack */ |
337 | ppp_tx_cp(dev, pid, code: CP_TERM_ACK, id, len: 0, NULL); |
338 | if (action & SCJ) /* send Code-Reject */ |
339 | ppp_tx_cp(dev, pid, code: CP_CODE_REJ, id: ++ppp->seq, len, data); |
340 | |
341 | if (old_state != OPENED && proto->state == OPENED) { |
342 | netdev_info(dev, format: "%s up\n" , proto_name(pid)); |
343 | if (pid == PID_LCP) { |
344 | netif_dormant_off(dev); |
345 | ppp_cp_event(dev, PID_IPCP, event: START, code: 0, id: 0, len: 0, NULL); |
346 | ppp_cp_event(dev, PID_IPV6CP, event: START, code: 0, id: 0, len: 0, NULL); |
347 | ppp->last_pong = jiffies; |
348 | mod_timer(timer: &proto->timer, expires: proto->timeout = |
349 | jiffies + ppp->keepalive_interval * HZ); |
350 | } |
351 | } |
352 | if (old_state == OPENED && proto->state != OPENED) { |
353 | netdev_info(dev, format: "%s down\n" , proto_name(pid)); |
354 | if (pid == PID_LCP) { |
355 | netif_dormant_on(dev); |
356 | ppp_cp_event(dev, PID_IPCP, event: STOP, code: 0, id: 0, len: 0, NULL); |
357 | ppp_cp_event(dev, PID_IPV6CP, event: STOP, code: 0, id: 0, len: 0, NULL); |
358 | } |
359 | } |
360 | if (old_state != CLOSED && proto->state == CLOSED) |
361 | del_timer(timer: &proto->timer); |
362 | |
363 | #if DEBUG_STATE |
364 | printk(KERN_DEBUG "%s: %s ppp_cp_event(%s) ... %s\n" , dev->name, |
365 | proto_name(pid), event_names[event], state_names[proto->state]); |
366 | #endif |
367 | } |
368 | |
369 | static void ppp_cp_parse_cr(struct net_device *dev, u16 pid, u8 id, |
370 | unsigned int req_len, const u8 *data) |
371 | { |
372 | static u8 const valid_accm[6] = { LCP_OPTION_ACCM, 6, 0, 0, 0, 0 }; |
373 | const u8 *opt; |
374 | u8 *out; |
375 | unsigned int len = req_len, nak_len = 0, rej_len = 0; |
376 | |
377 | out = kmalloc(size: len, GFP_ATOMIC); |
378 | if (!out) { |
379 | dev->stats.rx_dropped++; |
380 | return; /* out of memory, ignore CR packet */ |
381 | } |
382 | |
383 | for (opt = data; len; len -= opt[1], opt += opt[1]) { |
384 | if (len < 2 || opt[1] < 2 || len < opt[1]) |
385 | goto err_out; |
386 | |
387 | if (pid == PID_LCP) |
388 | switch (opt[0]) { |
389 | case LCP_OPTION_MRU: |
390 | continue; /* MRU always OK and > 1500 bytes? */ |
391 | |
392 | case LCP_OPTION_ACCM: /* async control character map */ |
393 | if (opt[1] < sizeof(valid_accm)) |
394 | goto err_out; |
395 | if (!memcmp(p: opt, q: valid_accm, |
396 | size: sizeof(valid_accm))) |
397 | continue; |
398 | if (!rej_len) { /* NAK it */ |
399 | memcpy(out + nak_len, valid_accm, |
400 | sizeof(valid_accm)); |
401 | nak_len += sizeof(valid_accm); |
402 | continue; |
403 | } |
404 | break; |
405 | case LCP_OPTION_MAGIC: |
406 | if (len < 6) |
407 | goto err_out; |
408 | if (opt[1] != 6 || (!opt[2] && !opt[3] && |
409 | !opt[4] && !opt[5])) |
410 | break; /* reject invalid magic number */ |
411 | continue; |
412 | } |
413 | /* reject this option */ |
414 | memcpy(out + rej_len, opt, opt[1]); |
415 | rej_len += opt[1]; |
416 | } |
417 | |
418 | if (rej_len) |
419 | ppp_cp_event(dev, pid, event: RCR_BAD, code: CP_CONF_REJ, id, len: rej_len, data: out); |
420 | else if (nak_len) |
421 | ppp_cp_event(dev, pid, event: RCR_BAD, code: CP_CONF_NAK, id, len: nak_len, data: out); |
422 | else |
423 | ppp_cp_event(dev, pid, event: RCR_GOOD, code: CP_CONF_ACK, id, len: req_len, data); |
424 | |
425 | kfree(objp: out); |
426 | return; |
427 | |
428 | err_out: |
429 | dev->stats.rx_errors++; |
430 | kfree(objp: out); |
431 | } |
432 | |
433 | static int ppp_rx(struct sk_buff *skb) |
434 | { |
435 | struct hdlc_header *hdr = (struct hdlc_header *)skb->data; |
436 | struct net_device *dev = skb->dev; |
437 | struct ppp *ppp = get_ppp(dev); |
438 | struct proto *proto; |
439 | struct cp_header *cp; |
440 | unsigned long flags; |
441 | unsigned int len; |
442 | u16 pid; |
443 | #if DEBUG_CP |
444 | int i; |
445 | char *ptr; |
446 | #endif |
447 | |
448 | spin_lock_irqsave(&ppp->lock, flags); |
449 | /* Check HDLC header */ |
450 | if (skb->len < sizeof(struct hdlc_header)) |
451 | goto rx_error; |
452 | cp = skb_pull(skb, len: sizeof(struct hdlc_header)); |
453 | if (hdr->address != HDLC_ADDR_ALLSTATIONS || |
454 | hdr->control != HDLC_CTRL_UI) |
455 | goto rx_error; |
456 | |
457 | pid = ntohs(hdr->protocol); |
458 | proto = get_proto(dev, pid); |
459 | if (!proto) { |
460 | if (ppp->protos[IDX_LCP].state == OPENED) |
461 | ppp_tx_cp(dev, PID_LCP, code: LCP_PROTO_REJ, |
462 | id: ++ppp->seq, len: skb->len + 2, data: &hdr->protocol); |
463 | goto rx_error; |
464 | } |
465 | |
466 | len = ntohs(cp->len); |
467 | if (len < sizeof(struct cp_header) /* no complete CP header? */ || |
468 | skb->len < len /* truncated packet? */) |
469 | goto rx_error; |
470 | skb_pull(skb, len: sizeof(struct cp_header)); |
471 | len -= sizeof(struct cp_header); |
472 | |
473 | /* HDLC and CP headers stripped from skb */ |
474 | #if DEBUG_CP |
475 | if (cp->code < CP_CODES) |
476 | sprintf(debug_buffer, "[%s id 0x%X]" , code_names[cp->code], |
477 | cp->id); |
478 | else |
479 | sprintf(debug_buffer, "[code %u id 0x%X]" , cp->code, cp->id); |
480 | ptr = debug_buffer + strlen(debug_buffer); |
481 | for (i = 0; i < min_t(unsigned int, len, DEBUG_CP); i++) { |
482 | sprintf(ptr, " %02X" , skb->data[i]); |
483 | ptr += strlen(ptr); |
484 | } |
485 | printk(KERN_DEBUG "%s: RX %s %s\n" , dev->name, proto_name(pid), |
486 | debug_buffer); |
487 | #endif |
488 | |
489 | /* LCP only */ |
490 | if (pid == PID_LCP) |
491 | switch (cp->code) { |
492 | case LCP_PROTO_REJ: |
493 | pid = ntohs(*(__be16 *)skb->data); |
494 | if (pid == PID_LCP || pid == PID_IPCP || |
495 | pid == PID_IPV6CP) |
496 | ppp_cp_event(dev, pid, event: RXJ_BAD, code: 0, id: 0, |
497 | len: 0, NULL); |
498 | goto out; |
499 | |
500 | case LCP_ECHO_REQ: /* send Echo-Reply */ |
501 | if (len >= 4 && proto->state == OPENED) |
502 | ppp_tx_cp(dev, PID_LCP, code: LCP_ECHO_REPLY, |
503 | id: cp->id, len: len - 4, data: skb->data + 4); |
504 | goto out; |
505 | |
506 | case LCP_ECHO_REPLY: |
507 | if (cp->id == ppp->echo_id) |
508 | ppp->last_pong = jiffies; |
509 | goto out; |
510 | |
511 | case LCP_DISC_REQ: /* discard */ |
512 | goto out; |
513 | } |
514 | |
515 | /* LCP, IPCP and IPV6CP */ |
516 | switch (cp->code) { |
517 | case CP_CONF_REQ: |
518 | ppp_cp_parse_cr(dev, pid, id: cp->id, req_len: len, data: skb->data); |
519 | break; |
520 | |
521 | case CP_CONF_ACK: |
522 | if (cp->id == proto->cr_id) |
523 | ppp_cp_event(dev, pid, event: RCA, code: 0, id: 0, len: 0, NULL); |
524 | break; |
525 | |
526 | case CP_CONF_REJ: |
527 | case CP_CONF_NAK: |
528 | if (cp->id == proto->cr_id) |
529 | ppp_cp_event(dev, pid, event: RCN, code: 0, id: 0, len: 0, NULL); |
530 | break; |
531 | |
532 | case CP_TERM_REQ: |
533 | ppp_cp_event(dev, pid, event: RTR, code: 0, id: cp->id, len: 0, NULL); |
534 | break; |
535 | |
536 | case CP_TERM_ACK: |
537 | ppp_cp_event(dev, pid, event: RTA, code: 0, id: 0, len: 0, NULL); |
538 | break; |
539 | |
540 | case CP_CODE_REJ: |
541 | ppp_cp_event(dev, pid, event: RXJ_BAD, code: 0, id: 0, len: 0, NULL); |
542 | break; |
543 | |
544 | default: |
545 | len += sizeof(struct cp_header); |
546 | if (len > dev->mtu) |
547 | len = dev->mtu; |
548 | ppp_cp_event(dev, pid, event: RUC, code: 0, id: 0, len, data: cp); |
549 | break; |
550 | } |
551 | goto out; |
552 | |
553 | rx_error: |
554 | dev->stats.rx_errors++; |
555 | out: |
556 | spin_unlock_irqrestore(lock: &ppp->lock, flags); |
557 | dev_kfree_skb_any(skb); |
558 | ppp_tx_flush(); |
559 | return NET_RX_DROP; |
560 | } |
561 | |
562 | static void ppp_timer(struct timer_list *t) |
563 | { |
564 | struct proto *proto = from_timer(proto, t, timer); |
565 | struct ppp *ppp = get_ppp(dev: proto->dev); |
566 | unsigned long flags; |
567 | |
568 | spin_lock_irqsave(&ppp->lock, flags); |
569 | /* mod_timer could be called after we entered this function but |
570 | * before we got the lock. |
571 | */ |
572 | if (timer_pending(timer: &proto->timer)) { |
573 | spin_unlock_irqrestore(lock: &ppp->lock, flags); |
574 | return; |
575 | } |
576 | switch (proto->state) { |
577 | case STOPPING: |
578 | case REQ_SENT: |
579 | case ACK_RECV: |
580 | case ACK_SENT: |
581 | if (proto->restart_counter) { |
582 | ppp_cp_event(dev: proto->dev, pid: proto->pid, event: TO_GOOD, code: 0, id: 0, |
583 | len: 0, NULL); |
584 | proto->restart_counter--; |
585 | } else if (netif_carrier_ok(dev: proto->dev)) |
586 | ppp_cp_event(dev: proto->dev, pid: proto->pid, event: TO_GOOD, code: 0, id: 0, |
587 | len: 0, NULL); |
588 | else |
589 | ppp_cp_event(dev: proto->dev, pid: proto->pid, event: TO_BAD, code: 0, id: 0, |
590 | len: 0, NULL); |
591 | break; |
592 | |
593 | case OPENED: |
594 | if (proto->pid != PID_LCP) |
595 | break; |
596 | if (time_after(jiffies, ppp->last_pong + |
597 | ppp->keepalive_timeout * HZ)) { |
598 | netdev_info(dev: proto->dev, format: "Link down\n" ); |
599 | ppp_cp_event(dev: proto->dev, PID_LCP, event: STOP, code: 0, id: 0, len: 0, NULL); |
600 | ppp_cp_event(dev: proto->dev, PID_LCP, event: START, code: 0, id: 0, len: 0, NULL); |
601 | } else { /* send keep-alive packet */ |
602 | ppp->echo_id = ++ppp->seq; |
603 | ppp_tx_cp(dev: proto->dev, PID_LCP, code: LCP_ECHO_REQ, |
604 | id: ppp->echo_id, len: 0, NULL); |
605 | proto->timer.expires = jiffies + |
606 | ppp->keepalive_interval * HZ; |
607 | add_timer(timer: &proto->timer); |
608 | } |
609 | break; |
610 | } |
611 | spin_unlock_irqrestore(lock: &ppp->lock, flags); |
612 | ppp_tx_flush(); |
613 | } |
614 | |
615 | static void ppp_start(struct net_device *dev) |
616 | { |
617 | struct ppp *ppp = get_ppp(dev); |
618 | int i; |
619 | |
620 | for (i = 0; i < IDX_COUNT; i++) { |
621 | struct proto *proto = &ppp->protos[i]; |
622 | |
623 | proto->dev = dev; |
624 | timer_setup(&proto->timer, ppp_timer, 0); |
625 | proto->state = CLOSED; |
626 | } |
627 | ppp->protos[IDX_LCP].pid = PID_LCP; |
628 | ppp->protos[IDX_IPCP].pid = PID_IPCP; |
629 | ppp->protos[IDX_IPV6CP].pid = PID_IPV6CP; |
630 | |
631 | ppp_cp_event(dev, PID_LCP, event: START, code: 0, id: 0, len: 0, NULL); |
632 | } |
633 | |
634 | static void ppp_stop(struct net_device *dev) |
635 | { |
636 | ppp_cp_event(dev, PID_LCP, event: STOP, code: 0, id: 0, len: 0, NULL); |
637 | } |
638 | |
639 | static void ppp_close(struct net_device *dev) |
640 | { |
641 | ppp_tx_flush(); |
642 | } |
643 | |
644 | static struct hdlc_proto proto = { |
645 | .start = ppp_start, |
646 | .stop = ppp_stop, |
647 | .close = ppp_close, |
648 | .type_trans = ppp_type_trans, |
649 | .ioctl = ppp_ioctl, |
650 | .netif_rx = ppp_rx, |
651 | .module = THIS_MODULE, |
652 | }; |
653 | |
654 | static const struct header_ops = { |
655 | .create = ppp_hard_header, |
656 | }; |
657 | |
658 | static int ppp_ioctl(struct net_device *dev, struct if_settings *ifs) |
659 | { |
660 | hdlc_device *hdlc = dev_to_hdlc(dev); |
661 | struct ppp *ppp; |
662 | int result; |
663 | |
664 | switch (ifs->type) { |
665 | case IF_GET_PROTO: |
666 | if (dev_to_hdlc(dev)->proto != &proto) |
667 | return -EINVAL; |
668 | ifs->type = IF_PROTO_PPP; |
669 | return 0; /* return protocol only, no settable parameters */ |
670 | |
671 | case IF_PROTO_PPP: |
672 | if (!capable(CAP_NET_ADMIN)) |
673 | return -EPERM; |
674 | |
675 | if (dev->flags & IFF_UP) |
676 | return -EBUSY; |
677 | |
678 | /* no settable parameters */ |
679 | |
680 | result = hdlc->attach(dev, ENCODING_NRZ, |
681 | PARITY_CRC16_PR1_CCITT); |
682 | if (result) |
683 | return result; |
684 | |
685 | result = attach_hdlc_protocol(dev, proto: &proto, size: sizeof(struct ppp)); |
686 | if (result) |
687 | return result; |
688 | |
689 | ppp = get_ppp(dev); |
690 | spin_lock_init(&ppp->lock); |
691 | ppp->req_timeout = 2; |
692 | ppp->cr_retries = 10; |
693 | ppp->term_retries = 2; |
694 | ppp->keepalive_interval = 10; |
695 | ppp->keepalive_timeout = 60; |
696 | |
697 | dev->hard_header_len = sizeof(struct hdlc_header); |
698 | dev->header_ops = &ppp_header_ops; |
699 | dev->type = ARPHRD_PPP; |
700 | call_netdevice_notifiers(val: NETDEV_POST_TYPE_CHANGE, dev); |
701 | netif_dormant_on(dev); |
702 | return 0; |
703 | } |
704 | |
705 | return -EINVAL; |
706 | } |
707 | |
708 | static int __init hdlc_ppp_init(void) |
709 | { |
710 | skb_queue_head_init(list: &tx_queue); |
711 | register_hdlc_protocol(proto: &proto); |
712 | return 0; |
713 | } |
714 | |
715 | static void __exit hdlc_ppp_exit(void) |
716 | { |
717 | unregister_hdlc_protocol(proto: &proto); |
718 | } |
719 | |
720 | module_init(hdlc_ppp_init); |
721 | module_exit(hdlc_ppp_exit); |
722 | |
723 | MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>" ); |
724 | MODULE_DESCRIPTION("PPP protocol support for generic HDLC" ); |
725 | MODULE_LICENSE("GPL v2" ); |
726 | |