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 DEBUG_HARD_HEADER 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 static char debug_buffer[64 + 3 * DEBUG_CP]; 45 #endif 46 47 enum {LCP_OPTION_MRU = 1, LCP_OPTION_ACCM, LCP_OPTION_MAGIC = 5}; 48 49 struct hdlc_header { 50 u8 address; 51 u8 control; 52 __be16 protocol; 53 }; 54 55 struct cp_header { 56 u8 code; 57 u8 id; 58 __be16 len; 59 }; 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 static const char *const event_names[EVENTS] = { 95 "Start", "Stop", "TO+", "TO-", "RCR+", "RCR-", "RCA", "RCN", 96 "RTR", "RTA", "RUC", "RXJ+", "RXJ-" 97 }; 98 #endif 99 100 static struct sk_buff_head tx_queue; /* used when holding the spin lock */ 101 102 static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr); 103 104 static inline struct ppp* get_ppp(struct net_device *dev) 105 { 106 return (struct ppp *)dev_to_hdlc(dev)->state; 107 } 108 109 static inline struct proto* get_proto(struct net_device *dev, u16 pid) 110 { 111 struct ppp *ppp = get_ppp(dev); 112 113 switch (pid) { 114 case PID_LCP: 115 return &ppp->protos[IDX_LCP]; 116 case PID_IPCP: 117 return &ppp->protos[IDX_IPCP]; 118 case PID_IPV6CP: 119 return &ppp->protos[IDX_IPV6CP]; 120 default: 121 return NULL; 122 } 123 } 124 125 static inline const char* proto_name(u16 pid) 126 { 127 switch (pid) { 128 case PID_LCP: 129 return "LCP"; 130 case PID_IPCP: 131 return "IPCP"; 132 case PID_IPV6CP: 133 return "IPV6CP"; 134 default: 135 return NULL; 136 } 137 } 138 139 static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev) 140 { 141 struct hdlc_header *data = (struct hdlc_header*)skb->data; 142 143 if (skb->len < sizeof(struct hdlc_header)) 144 return htons(ETH_P_HDLC); 145 if (data->address != HDLC_ADDR_ALLSTATIONS || 146 data->control != HDLC_CTRL_UI) 147 return htons(ETH_P_HDLC); 148 149 switch (data->protocol) { 150 case cpu_to_be16(PID_IP): 151 skb_pull(skb, sizeof(struct hdlc_header)); 152 return htons(ETH_P_IP); 153 154 case cpu_to_be16(PID_IPV6): 155 skb_pull(skb, sizeof(struct hdlc_header)); 156 return htons(ETH_P_IPV6); 157 158 default: 159 return htons(ETH_P_HDLC); 160 } 161 } 162 163 164 static int ppp_hard_header(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, 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 } 195 196 197 static void ppp_tx_flush(void) 198 { 199 struct sk_buff *skb; 200 while ((skb = skb_dequeue(&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(sizeof(struct hdlc_header) + 221 sizeof(struct cp_header) + magic_len + len); 222 if (!skb) { 223 netdev_warn(dev, "out of memory in ppp_tx_cp()\n"); 224 return; 225 } 226 skb_reserve(skb, sizeof(struct hdlc_header)); 227 228 cp = skb_put(skb, sizeof(struct cp_header)); 229 cp->code = code; 230 cp->id = id; 231 cp->len = htons(sizeof(struct cp_header) + magic_len + len); 232 233 if (magic_len) 234 skb_put_data(skb, &magic, magic_len); 235 if (len) 236 skb_put_data(skb, data, len); 237 238 #if DEBUG_CP 239 BUG_ON(code >= CP_CODES); 240 ptr = debug_buffer; 241 *ptr = '\x0'; 242 for (i = 0; i < min_t(unsigned int, magic_len + len, DEBUG_CP); i++) { 243 sprintf(ptr, " %02X", skb->data[sizeof(struct cp_header) + i]); 244 ptr += strlen(ptr); 245 } 246 printk(KERN_DEBUG "%s: TX %s [%s id 0x%X]%s\n", dev->name, 247 proto_name(pid), code_names[code], id, debug_buffer); 248 #endif 249 250 ppp_hard_header(skb, dev, pid, NULL, NULL, 0); 251 252 skb->priority = TC_PRIO_CONTROL; 253 skb->dev = dev; 254 skb->protocol = htons(ETH_P_HDLC); 255 skb_reset_network_header(skb); 256 skb_queue_tail(&tx_queue, skb); 257 } 258 259 260 /* State transition table (compare STD-51) 261 Events Actions 262 TO+ = Timeout with counter > 0 irc = Initialize-Restart-Count 263 TO- = Timeout with counter expired zrc = Zero-Restart-Count 264 265 RCR+ = Receive-Configure-Request (Good) scr = Send-Configure-Request 266 RCR- = Receive-Configure-Request (Bad) 267 RCA = Receive-Configure-Ack sca = Send-Configure-Ack 268 RCN = Receive-Configure-Nak/Rej scn = Send-Configure-Nak/Rej 269 270 RTR = Receive-Terminate-Request str = Send-Terminate-Request 271 RTA = Receive-Terminate-Ack sta = Send-Terminate-Ack 272 273 RUC = Receive-Unknown-Code scj = Send-Code-Reject 274 RXJ+ = Receive-Code-Reject (permitted) 275 or Receive-Protocol-Reject 276 RXJ- = Receive-Code-Reject (catastrophic) 277 or Receive-Protocol-Reject 278 */ 279 static int cp_table[EVENTS][STATES] = { 280 /* CLOSED STOPPED STOPPING REQ_SENT ACK_RECV ACK_SENT OPENED 281 0 1 2 3 4 5 6 */ 282 {IRC|SCR|3, INV , INV , INV , INV , INV , INV }, /* START */ 283 { INV , 0 , 0 , 0 , 0 , 0 , 0 }, /* STOP */ 284 { INV , INV ,STR|2, SCR|3 ,SCR|3, SCR|5 , INV }, /* TO+ */ 285 { INV , INV , 1 , 1 , 1 , 1 , INV }, /* TO- */ 286 { STA|0 ,IRC|SCR|SCA|5, 2 , SCA|5 ,SCA|6, SCA|5 ,SCR|SCA|5}, /* RCR+ */ 287 { STA|0 ,IRC|SCR|SCN|3, 2 , SCN|3 ,SCN|4, SCN|3 ,SCR|SCN|3}, /* RCR- */ 288 { STA|0 , STA|1 , 2 , IRC|4 ,SCR|3, 6 , SCR|3 }, /* RCA */ 289 { STA|0 , STA|1 , 2 ,IRC|SCR|3,SCR|3,IRC|SCR|5, SCR|3 }, /* RCN */ 290 { STA|0 , STA|1 ,STA|2, STA|3 ,STA|3, STA|3 ,ZRC|STA|2}, /* RTR */ 291 { 0 , 1 , 1 , 3 , 3 , 5 , SCR|3 }, /* RTA */ 292 { SCJ|0 , SCJ|1 ,SCJ|2, SCJ|3 ,SCJ|4, SCJ|5 , SCJ|6 }, /* RUC */ 293 { 0 , 1 , 2 , 3 , 3 , 5 , 6 }, /* RXJ+ */ 294 { 0 , 1 , 1 , 1 , 1 , 1 ,IRC|STR|2}, /* RXJ- */ 295 }; 296 297 298 /* SCA: RCR+ must supply id, len and data 299 SCN: RCR- must supply code, id, len and data 300 STA: RTR must supply id 301 SCJ: RUC must supply CP packet len and data */ 302 static void ppp_cp_event(struct net_device *dev, u16 pid, u16 event, u8 code, 303 u8 id, unsigned int len, const void *data) 304 { 305 int old_state, action; 306 struct ppp *ppp = get_ppp(dev); 307 struct proto *proto = get_proto(dev, pid); 308 309 old_state = proto->state; 310 BUG_ON(old_state >= STATES); 311 BUG_ON(event >= EVENTS); 312 313 #if DEBUG_STATE 314 printk(KERN_DEBUG "%s: %s ppp_cp_event(%s) %s ...\n", dev->name, 315 proto_name(pid), event_names[event], state_names[proto->state]); 316 #endif 317 318 action = cp_table[event][old_state]; 319 320 proto->state = action & STATE_MASK; 321 if (action & (SCR | STR)) /* set Configure-Req/Terminate-Req timer */ 322 mod_timer(&proto->timer, proto->timeout = 323 jiffies + ppp->req_timeout * HZ); 324 if (action & ZRC) 325 proto->restart_counter = 0; 326 if (action & IRC) 327 proto->restart_counter = (proto->state == STOPPING) ? 328 ppp->term_retries : ppp->cr_retries; 329 330 if (action & SCR) /* send Configure-Request */ 331 ppp_tx_cp(dev, pid, CP_CONF_REQ, proto->cr_id = ++ppp->seq, 332 0, NULL); 333 if (action & SCA) /* send Configure-Ack */ 334 ppp_tx_cp(dev, pid, CP_CONF_ACK, id, len, data); 335 if (action & SCN) /* send Configure-Nak/Reject */ 336 ppp_tx_cp(dev, pid, code, id, len, data); 337 if (action & STR) /* send Terminate-Request */ 338 ppp_tx_cp(dev, pid, CP_TERM_REQ, ++ppp->seq, 0, NULL); 339 if (action & STA) /* send Terminate-Ack */ 340 ppp_tx_cp(dev, pid, CP_TERM_ACK, id, 0, NULL); 341 if (action & SCJ) /* send Code-Reject */ 342 ppp_tx_cp(dev, pid, CP_CODE_REJ, ++ppp->seq, len, data); 343 344 if (old_state != OPENED && proto->state == OPENED) { 345 netdev_info(dev, "%s up\n", proto_name(pid)); 346 if (pid == PID_LCP) { 347 netif_dormant_off(dev); 348 ppp_cp_event(dev, PID_IPCP, START, 0, 0, 0, NULL); 349 ppp_cp_event(dev, PID_IPV6CP, START, 0, 0, 0, NULL); 350 ppp->last_pong = jiffies; 351 mod_timer(&proto->timer, proto->timeout = 352 jiffies + ppp->keepalive_interval * HZ); 353 } 354 } 355 if (old_state == OPENED && proto->state != OPENED) { 356 netdev_info(dev, "%s down\n", proto_name(pid)); 357 if (pid == PID_LCP) { 358 netif_dormant_on(dev); 359 ppp_cp_event(dev, PID_IPCP, STOP, 0, 0, 0, NULL); 360 ppp_cp_event(dev, PID_IPV6CP, STOP, 0, 0, 0, NULL); 361 } 362 } 363 if (old_state != CLOSED && proto->state == CLOSED) 364 del_timer(&proto->timer); 365 366 #if DEBUG_STATE 367 printk(KERN_DEBUG "%s: %s ppp_cp_event(%s) ... %s\n", dev->name, 368 proto_name(pid), event_names[event], state_names[proto->state]); 369 #endif 370 } 371 372 373 static void ppp_cp_parse_cr(struct net_device *dev, u16 pid, u8 id, 374 unsigned int req_len, const u8 *data) 375 { 376 static u8 const valid_accm[6] = { LCP_OPTION_ACCM, 6, 0, 0, 0, 0 }; 377 const u8 *opt; 378 u8 *out; 379 unsigned int len = req_len, nak_len = 0, rej_len = 0; 380 381 if (!(out = kmalloc(len, GFP_ATOMIC))) { 382 dev->stats.rx_dropped++; 383 return; /* out of memory, ignore CR packet */ 384 } 385 386 for (opt = data; len; len -= opt[1], opt += opt[1]) { 387 if (len < 2 || opt[1] < 2 || len < opt[1]) 388 goto err_out; 389 390 if (pid == PID_LCP) 391 switch (opt[0]) { 392 case LCP_OPTION_MRU: 393 continue; /* MRU always OK and > 1500 bytes? */ 394 395 case LCP_OPTION_ACCM: /* async control character map */ 396 if (opt[1] < sizeof(valid_accm)) 397 goto err_out; 398 if (!memcmp(opt, valid_accm, 399 sizeof(valid_accm))) 400 continue; 401 if (!rej_len) { /* NAK it */ 402 memcpy(out + nak_len, valid_accm, 403 sizeof(valid_accm)); 404 nak_len += sizeof(valid_accm); 405 continue; 406 } 407 break; 408 case LCP_OPTION_MAGIC: 409 if (len < 6) 410 goto err_out; 411 if (opt[1] != 6 || (!opt[2] && !opt[3] && 412 !opt[4] && !opt[5])) 413 break; /* reject invalid magic number */ 414 continue; 415 } 416 /* reject this option */ 417 memcpy(out + rej_len, opt, opt[1]); 418 rej_len += opt[1]; 419 } 420 421 if (rej_len) 422 ppp_cp_event(dev, pid, RCR_BAD, CP_CONF_REJ, id, rej_len, out); 423 else if (nak_len) 424 ppp_cp_event(dev, pid, RCR_BAD, CP_CONF_NAK, id, nak_len, out); 425 else 426 ppp_cp_event(dev, pid, RCR_GOOD, CP_CONF_ACK, id, req_len, data); 427 428 kfree(out); 429 return; 430 431 err_out: 432 dev->stats.rx_errors++; 433 kfree(out); 434 } 435 436 static int ppp_rx(struct sk_buff *skb) 437 { 438 struct hdlc_header *hdr = (struct hdlc_header*)skb->data; 439 struct net_device *dev = skb->dev; 440 struct ppp *ppp = get_ppp(dev); 441 struct proto *proto; 442 struct cp_header *cp; 443 unsigned long flags; 444 unsigned int len; 445 u16 pid; 446 #if DEBUG_CP 447 int i; 448 char *ptr; 449 #endif 450 451 spin_lock_irqsave(&ppp->lock, flags); 452 /* Check HDLC header */ 453 if (skb->len < sizeof(struct hdlc_header)) 454 goto rx_error; 455 cp = skb_pull(skb, sizeof(struct hdlc_header)); 456 if (hdr->address != HDLC_ADDR_ALLSTATIONS || 457 hdr->control != HDLC_CTRL_UI) 458 goto rx_error; 459 460 pid = ntohs(hdr->protocol); 461 proto = get_proto(dev, pid); 462 if (!proto) { 463 if (ppp->protos[IDX_LCP].state == OPENED) 464 ppp_tx_cp(dev, PID_LCP, LCP_PROTO_REJ, 465 ++ppp->seq, skb->len + 2, &hdr->protocol); 466 goto rx_error; 467 } 468 469 len = ntohs(cp->len); 470 if (len < sizeof(struct cp_header) /* no complete CP header? */ || 471 skb->len < len /* truncated packet? */) 472 goto rx_error; 473 skb_pull(skb, sizeof(struct cp_header)); 474 len -= sizeof(struct cp_header); 475 476 /* HDLC and CP headers stripped from skb */ 477 #if DEBUG_CP 478 if (cp->code < CP_CODES) 479 sprintf(debug_buffer, "[%s id 0x%X]", code_names[cp->code], 480 cp->id); 481 else 482 sprintf(debug_buffer, "[code %u id 0x%X]", cp->code, cp->id); 483 ptr = debug_buffer + strlen(debug_buffer); 484 for (i = 0; i < min_t(unsigned int, len, DEBUG_CP); i++) { 485 sprintf(ptr, " %02X", skb->data[i]); 486 ptr += strlen(ptr); 487 } 488 printk(KERN_DEBUG "%s: RX %s %s\n", dev->name, proto_name(pid), 489 debug_buffer); 490 #endif 491 492 /* LCP only */ 493 if (pid == PID_LCP) 494 switch (cp->code) { 495 case LCP_PROTO_REJ: 496 pid = ntohs(*(__be16*)skb->data); 497 if (pid == PID_LCP || pid == PID_IPCP || 498 pid == PID_IPV6CP) 499 ppp_cp_event(dev, pid, RXJ_BAD, 0, 0, 500 0, NULL); 501 goto out; 502 503 case LCP_ECHO_REQ: /* send Echo-Reply */ 504 if (len >= 4 && proto->state == OPENED) 505 ppp_tx_cp(dev, PID_LCP, LCP_ECHO_REPLY, 506 cp->id, len - 4, skb->data + 4); 507 goto out; 508 509 case LCP_ECHO_REPLY: 510 if (cp->id == ppp->echo_id) 511 ppp->last_pong = jiffies; 512 goto out; 513 514 case LCP_DISC_REQ: /* discard */ 515 goto out; 516 } 517 518 /* LCP, IPCP and IPV6CP */ 519 switch (cp->code) { 520 case CP_CONF_REQ: 521 ppp_cp_parse_cr(dev, pid, cp->id, len, skb->data); 522 break; 523 524 case CP_CONF_ACK: 525 if (cp->id == proto->cr_id) 526 ppp_cp_event(dev, pid, RCA, 0, 0, 0, NULL); 527 break; 528 529 case CP_CONF_REJ: 530 case CP_CONF_NAK: 531 if (cp->id == proto->cr_id) 532 ppp_cp_event(dev, pid, RCN, 0, 0, 0, NULL); 533 break; 534 535 case CP_TERM_REQ: 536 ppp_cp_event(dev, pid, RTR, 0, cp->id, 0, NULL); 537 break; 538 539 case CP_TERM_ACK: 540 ppp_cp_event(dev, pid, RTA, 0, 0, 0, NULL); 541 break; 542 543 case CP_CODE_REJ: 544 ppp_cp_event(dev, pid, RXJ_BAD, 0, 0, 0, NULL); 545 break; 546 547 default: 548 len += sizeof(struct cp_header); 549 if (len > dev->mtu) 550 len = dev->mtu; 551 ppp_cp_event(dev, pid, RUC, 0, 0, len, cp); 552 break; 553 } 554 goto out; 555 556 rx_error: 557 dev->stats.rx_errors++; 558 out: 559 spin_unlock_irqrestore(&ppp->lock, flags); 560 dev_kfree_skb_any(skb); 561 ppp_tx_flush(); 562 return NET_RX_DROP; 563 } 564 565 static void ppp_timer(struct timer_list *t) 566 { 567 struct proto *proto = from_timer(proto, t, timer); 568 struct ppp *ppp = get_ppp(proto->dev); 569 unsigned long flags; 570 571 spin_lock_irqsave(&ppp->lock, flags); 572 /* mod_timer could be called after we entered this function but 573 * before we got the lock. 574 */ 575 if (timer_pending(&proto->timer)) { 576 spin_unlock_irqrestore(&ppp->lock, flags); 577 return; 578 } 579 switch (proto->state) { 580 case STOPPING: 581 case REQ_SENT: 582 case ACK_RECV: 583 case ACK_SENT: 584 if (proto->restart_counter) { 585 ppp_cp_event(proto->dev, proto->pid, TO_GOOD, 0, 0, 586 0, NULL); 587 proto->restart_counter--; 588 } else if (netif_carrier_ok(proto->dev)) 589 ppp_cp_event(proto->dev, proto->pid, TO_GOOD, 0, 0, 590 0, NULL); 591 else 592 ppp_cp_event(proto->dev, proto->pid, TO_BAD, 0, 0, 593 0, NULL); 594 break; 595 596 case OPENED: 597 if (proto->pid != PID_LCP) 598 break; 599 if (time_after(jiffies, ppp->last_pong + 600 ppp->keepalive_timeout * HZ)) { 601 netdev_info(proto->dev, "Link down\n"); 602 ppp_cp_event(proto->dev, PID_LCP, STOP, 0, 0, 0, NULL); 603 ppp_cp_event(proto->dev, PID_LCP, START, 0, 0, 0, NULL); 604 } else { /* send keep-alive packet */ 605 ppp->echo_id = ++ppp->seq; 606 ppp_tx_cp(proto->dev, PID_LCP, LCP_ECHO_REQ, 607 ppp->echo_id, 0, NULL); 608 proto->timer.expires = jiffies + 609 ppp->keepalive_interval * HZ; 610 add_timer(&proto->timer); 611 } 612 break; 613 } 614 spin_unlock_irqrestore(&ppp->lock, flags); 615 ppp_tx_flush(); 616 } 617 618 619 static void ppp_start(struct net_device *dev) 620 { 621 struct ppp *ppp = get_ppp(dev); 622 int i; 623 624 for (i = 0; i < IDX_COUNT; i++) { 625 struct proto *proto = &ppp->protos[i]; 626 proto->dev = dev; 627 timer_setup(&proto->timer, ppp_timer, 0); 628 proto->state = CLOSED; 629 } 630 ppp->protos[IDX_LCP].pid = PID_LCP; 631 ppp->protos[IDX_IPCP].pid = PID_IPCP; 632 ppp->protos[IDX_IPV6CP].pid = PID_IPV6CP; 633 634 ppp_cp_event(dev, PID_LCP, START, 0, 0, 0, NULL); 635 } 636 637 static void ppp_stop(struct net_device *dev) 638 { 639 ppp_cp_event(dev, PID_LCP, STOP, 0, 0, 0, NULL); 640 } 641 642 static void ppp_close(struct net_device *dev) 643 { 644 ppp_tx_flush(); 645 } 646 647 static struct hdlc_proto proto = { 648 .start = ppp_start, 649 .stop = ppp_stop, 650 .close = ppp_close, 651 .type_trans = ppp_type_trans, 652 .ioctl = ppp_ioctl, 653 .netif_rx = ppp_rx, 654 .module = THIS_MODULE, 655 }; 656 657 static const struct header_ops ppp_header_ops = { 658 .create = ppp_hard_header, 659 }; 660 661 static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr) 662 { 663 hdlc_device *hdlc = dev_to_hdlc(dev); 664 struct ppp *ppp; 665 int result; 666 667 switch (ifr->ifr_settings.type) { 668 case IF_GET_PROTO: 669 if (dev_to_hdlc(dev)->proto != &proto) 670 return -EINVAL; 671 ifr->ifr_settings.type = IF_PROTO_PPP; 672 return 0; /* return protocol only, no settable parameters */ 673 674 case IF_PROTO_PPP: 675 if (!capable(CAP_NET_ADMIN)) 676 return -EPERM; 677 678 if (dev->flags & IFF_UP) 679 return -EBUSY; 680 681 /* no settable parameters */ 682 683 result = hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT); 684 if (result) 685 return result; 686 687 result = attach_hdlc_protocol(dev, &proto, sizeof(struct ppp)); 688 if (result) 689 return result; 690 691 ppp = get_ppp(dev); 692 spin_lock_init(&ppp->lock); 693 ppp->req_timeout = 2; 694 ppp->cr_retries = 10; 695 ppp->term_retries = 2; 696 ppp->keepalive_interval = 10; 697 ppp->keepalive_timeout = 60; 698 699 dev->hard_header_len = sizeof(struct hdlc_header); 700 dev->header_ops = &ppp_header_ops; 701 dev->type = ARPHRD_PPP; 702 call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev); 703 netif_dormant_on(dev); 704 return 0; 705 } 706 707 return -EINVAL; 708 } 709 710 711 static int __init mod_init(void) 712 { 713 skb_queue_head_init(&tx_queue); 714 register_hdlc_protocol(&proto); 715 return 0; 716 } 717 718 static void __exit mod_exit(void) 719 { 720 unregister_hdlc_protocol(&proto); 721 } 722 723 724 module_init(mod_init); 725 module_exit(mod_exit); 726 727 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>"); 728 MODULE_DESCRIPTION("PPP protocol support for generic HDLC"); 729 MODULE_LICENSE("GPL v2"); 730