xref: /openbmc/linux/net/ipv4/ipconfig.c (revision 293d5b43)
1 /*
2  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
3  *  user-supplied information to configure own IP address and routes.
4  *
5  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
6  *
7  *  Derived from network configuration code in fs/nfs/nfsroot.c,
8  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
9  *
10  *  BOOTP rewritten to construct and analyse packets itself instead
11  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
12  *					     -- MJ, December 1998
13  *
14  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
15  *  initialization scheme.
16  *	- Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
17  *
18  *  DHCP support added.  To users this looks like a whole separate
19  *  protocol, but we know it's just a bag on the side of BOOTP.
20  *		-- Chip Salzenberg <chip@valinux.com>, May 2000
21  *
22  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
23  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
24  *
25  *  Merged changes from 2.2.19 into 2.4.3
26  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
27  *
28  *  Multiple Nameservers in /proc/net/pnp
29  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
30  */
31 
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/kernel.h>
35 #include <linux/jiffies.h>
36 #include <linux/random.h>
37 #include <linux/init.h>
38 #include <linux/utsname.h>
39 #include <linux/in.h>
40 #include <linux/if.h>
41 #include <linux/inet.h>
42 #include <linux/inetdevice.h>
43 #include <linux/netdevice.h>
44 #include <linux/if_arp.h>
45 #include <linux/skbuff.h>
46 #include <linux/ip.h>
47 #include <linux/socket.h>
48 #include <linux/route.h>
49 #include <linux/udp.h>
50 #include <linux/proc_fs.h>
51 #include <linux/seq_file.h>
52 #include <linux/major.h>
53 #include <linux/root_dev.h>
54 #include <linux/delay.h>
55 #include <linux/nfs_fs.h>
56 #include <linux/slab.h>
57 #include <linux/export.h>
58 #include <net/net_namespace.h>
59 #include <net/arp.h>
60 #include <net/ip.h>
61 #include <net/ipconfig.h>
62 #include <net/route.h>
63 
64 #include <asm/uaccess.h>
65 #include <net/checksum.h>
66 #include <asm/processor.h>
67 
68 #if defined(CONFIG_IP_PNP_DHCP)
69 #define IPCONFIG_DHCP
70 #endif
71 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
72 #define IPCONFIG_BOOTP
73 #endif
74 #if defined(CONFIG_IP_PNP_RARP)
75 #define IPCONFIG_RARP
76 #endif
77 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
78 #define IPCONFIG_DYNAMIC
79 #endif
80 
81 /* Define the friendly delay before and after opening net devices */
82 #define CONF_POST_OPEN		10	/* After opening: 10 msecs */
83 #define CONF_CARRIER_TIMEOUT	120000	/* Wait for carrier timeout */
84 
85 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
86 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
87 #define CONF_SEND_RETRIES 	6	/* Send six requests per open */
88 #define CONF_INTER_TIMEOUT	(HZ)	/* Inter-device timeout: 1 second */
89 #define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
90 #define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
91 #define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
92 #define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
93 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
94 					   - '3' from resolv.h */
95 
96 #define NONE cpu_to_be32(INADDR_NONE)
97 #define ANY cpu_to_be32(INADDR_ANY)
98 
99 /*
100  * Public IP configuration
101  */
102 
103 /* This is used by platforms which might be able to set the ipconfig
104  * variables using firmware environment vars.  If this is set, it will
105  * ignore such firmware variables.
106  */
107 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
108 
109 static int ic_enable __initdata;		/* IP config enabled? */
110 
111 /* Protocol choice */
112 int ic_proto_enabled __initdata = 0
113 #ifdef IPCONFIG_BOOTP
114 			| IC_BOOTP
115 #endif
116 #ifdef CONFIG_IP_PNP_DHCP
117 			| IC_USE_DHCP
118 #endif
119 #ifdef IPCONFIG_RARP
120 			| IC_RARP
121 #endif
122 			;
123 
124 static int ic_host_name_set __initdata;	/* Host name set by us? */
125 
126 __be32 ic_myaddr = NONE;		/* My IP address */
127 static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
128 __be32 ic_gateway = NONE;	/* Gateway IP address */
129 
130 #ifdef IPCONFIG_DYNAMIC
131 static __be32 ic_addrservaddr = NONE;	/* IP Address of the IP addresses'server */
132 #endif
133 
134 __be32 ic_servaddr = NONE;	/* Boot server IP address */
135 
136 __be32 root_server_addr = NONE;	/* Address of NFS server */
137 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
138 
139 /* vendor class identifier */
140 static char vendor_class_identifier[253] __initdata;
141 
142 #if defined(CONFIG_IP_PNP_DHCP)
143 static char dhcp_client_identifier[253] __initdata;
144 #endif
145 
146 /* Persistent data: */
147 
148 #ifdef IPCONFIG_DYNAMIC
149 static int ic_proto_used;			/* Protocol used, if any */
150 #else
151 #define ic_proto_used 0
152 #endif
153 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
154 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
155 
156 /*
157  * Private state.
158  */
159 
160 /* Name of user-selected boot device */
161 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
162 
163 /* Protocols supported by available interfaces */
164 static int ic_proto_have_if __initdata;
165 
166 /* MTU for boot device */
167 static int ic_dev_mtu __initdata;
168 
169 #ifdef IPCONFIG_DYNAMIC
170 static DEFINE_SPINLOCK(ic_recv_lock);
171 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
172 #endif
173 #ifdef IPCONFIG_DHCP
174 static int ic_dhcp_msgtype __initdata;	/* DHCP msg type received */
175 #endif
176 
177 
178 /*
179  *	Network devices
180  */
181 
182 struct ic_device {
183 	struct ic_device *next;
184 	struct net_device *dev;
185 	unsigned short flags;
186 	short able;
187 	__be32 xid;
188 };
189 
190 static struct ic_device *ic_first_dev __initdata;	/* List of open device */
191 static struct net_device *ic_dev __initdata;		/* Selected device */
192 
193 static bool __init ic_is_init_dev(struct net_device *dev)
194 {
195 	if (dev->flags & IFF_LOOPBACK)
196 		return false;
197 	return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
198 	    (!(dev->flags & IFF_LOOPBACK) &&
199 	     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
200 	     strncmp(dev->name, "dummy", 5));
201 }
202 
203 static int __init ic_open_devs(void)
204 {
205 	struct ic_device *d, **last;
206 	struct net_device *dev;
207 	unsigned short oflags;
208 	unsigned long start, next_msg;
209 
210 	last = &ic_first_dev;
211 	rtnl_lock();
212 
213 	/* bring loopback and DSA master network devices up first */
214 	for_each_netdev(&init_net, dev) {
215 		if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
216 			continue;
217 		if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
218 			pr_err("IP-Config: Failed to open %s\n", dev->name);
219 	}
220 
221 	for_each_netdev(&init_net, dev) {
222 		if (ic_is_init_dev(dev)) {
223 			int able = 0;
224 			if (dev->mtu >= 364)
225 				able |= IC_BOOTP;
226 			else
227 				pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
228 					dev->name, dev->mtu);
229 			if (!(dev->flags & IFF_NOARP))
230 				able |= IC_RARP;
231 			able &= ic_proto_enabled;
232 			if (ic_proto_enabled && !able)
233 				continue;
234 			oflags = dev->flags;
235 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
236 				pr_err("IP-Config: Failed to open %s\n",
237 				       dev->name);
238 				continue;
239 			}
240 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
241 				rtnl_unlock();
242 				return -ENOMEM;
243 			}
244 			d->dev = dev;
245 			*last = d;
246 			last = &d->next;
247 			d->flags = oflags;
248 			d->able = able;
249 			if (able & IC_BOOTP)
250 				get_random_bytes(&d->xid, sizeof(__be32));
251 			else
252 				d->xid = 0;
253 			ic_proto_have_if |= able;
254 			pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
255 				 dev->name, able, d->xid);
256 		}
257 	}
258 
259 	/* no point in waiting if we could not bring up at least one device */
260 	if (!ic_first_dev)
261 		goto have_carrier;
262 
263 	/* wait for a carrier on at least one device */
264 	start = jiffies;
265 	next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
266 	while (time_before(jiffies, start +
267 			   msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
268 		int wait, elapsed;
269 
270 		for_each_netdev(&init_net, dev)
271 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
272 				goto have_carrier;
273 
274 		msleep(1);
275 
276 		if (time_before(jiffies, next_msg))
277 			continue;
278 
279 		elapsed = jiffies_to_msecs(jiffies - start);
280 		wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
281 		pr_info("Waiting up to %d more seconds for network.\n", wait);
282 		next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
283 	}
284 have_carrier:
285 	rtnl_unlock();
286 
287 	*last = NULL;
288 
289 	if (!ic_first_dev) {
290 		if (user_dev_name[0])
291 			pr_err("IP-Config: Device `%s' not found\n",
292 			       user_dev_name);
293 		else
294 			pr_err("IP-Config: No network devices available\n");
295 		return -ENODEV;
296 	}
297 	return 0;
298 }
299 
300 static void __init ic_close_devs(void)
301 {
302 	struct ic_device *d, *next;
303 	struct net_device *dev;
304 
305 	rtnl_lock();
306 	next = ic_first_dev;
307 	while ((d = next)) {
308 		next = d->next;
309 		dev = d->dev;
310 		if (dev != ic_dev && !netdev_uses_dsa(dev)) {
311 			pr_debug("IP-Config: Downing %s\n", dev->name);
312 			dev_change_flags(dev, d->flags);
313 		}
314 		kfree(d);
315 	}
316 	rtnl_unlock();
317 }
318 
319 /*
320  *	Interface to various network functions.
321  */
322 
323 static inline void
324 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
325 {
326 	sin->sin_family = AF_INET;
327 	sin->sin_addr.s_addr = addr;
328 	sin->sin_port = port;
329 }
330 
331 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
332 {
333 	int res;
334 
335 	mm_segment_t oldfs = get_fs();
336 	set_fs(get_ds());
337 	res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
338 	set_fs(oldfs);
339 	return res;
340 }
341 
342 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
343 {
344 	int res;
345 
346 	mm_segment_t oldfs = get_fs();
347 	set_fs(get_ds());
348 	res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
349 	set_fs(oldfs);
350 	return res;
351 }
352 
353 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
354 {
355 	int res;
356 
357 	mm_segment_t oldfs = get_fs();
358 	set_fs(get_ds());
359 	res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
360 	set_fs(oldfs);
361 	return res;
362 }
363 
364 /*
365  *	Set up interface addresses and routes.
366  */
367 
368 static int __init ic_setup_if(void)
369 {
370 	struct ifreq ir;
371 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
372 	int err;
373 
374 	memset(&ir, 0, sizeof(ir));
375 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
376 	set_sockaddr(sin, ic_myaddr, 0);
377 	if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
378 		pr_err("IP-Config: Unable to set interface address (%d)\n",
379 		       err);
380 		return -1;
381 	}
382 	set_sockaddr(sin, ic_netmask, 0);
383 	if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
384 		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
385 		       err);
386 		return -1;
387 	}
388 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
389 	if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
390 		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
391 		       err);
392 		return -1;
393 	}
394 	/* Handle the case where we need non-standard MTU on the boot link (a network
395 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
396 	 * out, we'll try to muddle along.
397 	 */
398 	if (ic_dev_mtu != 0) {
399 		strcpy(ir.ifr_name, ic_dev->name);
400 		ir.ifr_mtu = ic_dev_mtu;
401 		if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
402 			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
403 			       ic_dev_mtu, err);
404 	}
405 	return 0;
406 }
407 
408 static int __init ic_setup_routes(void)
409 {
410 	/* No need to setup device routes, only the default route... */
411 
412 	if (ic_gateway != NONE) {
413 		struct rtentry rm;
414 		int err;
415 
416 		memset(&rm, 0, sizeof(rm));
417 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
418 			pr_err("IP-Config: Gateway not on directly connected network\n");
419 			return -1;
420 		}
421 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
422 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
423 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
424 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
425 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
426 			pr_err("IP-Config: Cannot add default route (%d)\n",
427 			       err);
428 			return -1;
429 		}
430 	}
431 
432 	return 0;
433 }
434 
435 /*
436  *	Fill in default values for all missing parameters.
437  */
438 
439 static int __init ic_defaults(void)
440 {
441 	/*
442 	 *	At this point we have no userspace running so need not
443 	 *	claim locks on system_utsname
444 	 */
445 
446 	if (!ic_host_name_set)
447 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
448 
449 	if (root_server_addr == NONE)
450 		root_server_addr = ic_servaddr;
451 
452 	if (ic_netmask == NONE) {
453 		if (IN_CLASSA(ntohl(ic_myaddr)))
454 			ic_netmask = htonl(IN_CLASSA_NET);
455 		else if (IN_CLASSB(ntohl(ic_myaddr)))
456 			ic_netmask = htonl(IN_CLASSB_NET);
457 		else if (IN_CLASSC(ntohl(ic_myaddr)))
458 			ic_netmask = htonl(IN_CLASSC_NET);
459 		else {
460 			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
461 			       &ic_myaddr);
462 			return -1;
463 		}
464 		pr_notice("IP-Config: Guessing netmask %pI4\n",
465 			  &ic_netmask);
466 	}
467 
468 	return 0;
469 }
470 
471 /*
472  *	RARP support.
473  */
474 
475 #ifdef IPCONFIG_RARP
476 
477 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
478 
479 static struct packet_type rarp_packet_type __initdata = {
480 	.type =	cpu_to_be16(ETH_P_RARP),
481 	.func =	ic_rarp_recv,
482 };
483 
484 static inline void __init ic_rarp_init(void)
485 {
486 	dev_add_pack(&rarp_packet_type);
487 }
488 
489 static inline void __init ic_rarp_cleanup(void)
490 {
491 	dev_remove_pack(&rarp_packet_type);
492 }
493 
494 /*
495  *  Process received RARP packet.
496  */
497 static int __init
498 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
499 {
500 	struct arphdr *rarp;
501 	unsigned char *rarp_ptr;
502 	__be32 sip, tip;
503 	unsigned char *tha;		/* t for "target" */
504 	struct ic_device *d;
505 
506 	if (!net_eq(dev_net(dev), &init_net))
507 		goto drop;
508 
509 	skb = skb_share_check(skb, GFP_ATOMIC);
510 	if (!skb)
511 		return NET_RX_DROP;
512 
513 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
514 		goto drop;
515 
516 	/* Basic sanity checks can be done without the lock.  */
517 	rarp = (struct arphdr *)skb_transport_header(skb);
518 
519 	/* If this test doesn't pass, it's not IP, or we should
520 	 * ignore it anyway.
521 	 */
522 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
523 		goto drop;
524 
525 	/* If it's not a RARP reply, delete it. */
526 	if (rarp->ar_op != htons(ARPOP_RREPLY))
527 		goto drop;
528 
529 	/* If it's not Ethernet, delete it. */
530 	if (rarp->ar_pro != htons(ETH_P_IP))
531 		goto drop;
532 
533 	if (!pskb_may_pull(skb, arp_hdr_len(dev)))
534 		goto drop;
535 
536 	/* OK, it is all there and looks valid, process... */
537 	rarp = (struct arphdr *)skb_transport_header(skb);
538 	rarp_ptr = (unsigned char *) (rarp + 1);
539 
540 	/* One reply at a time, please. */
541 	spin_lock(&ic_recv_lock);
542 
543 	/* If we already have a reply, just drop the packet */
544 	if (ic_got_reply)
545 		goto drop_unlock;
546 
547 	/* Find the ic_device that the packet arrived on */
548 	d = ic_first_dev;
549 	while (d && d->dev != dev)
550 		d = d->next;
551 	if (!d)
552 		goto drop_unlock;	/* should never happen */
553 
554 	/* Extract variable-width fields */
555 	rarp_ptr += dev->addr_len;
556 	memcpy(&sip, rarp_ptr, 4);
557 	rarp_ptr += 4;
558 	tha = rarp_ptr;
559 	rarp_ptr += dev->addr_len;
560 	memcpy(&tip, rarp_ptr, 4);
561 
562 	/* Discard packets which are not meant for us. */
563 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
564 		goto drop_unlock;
565 
566 	/* Discard packets which are not from specified server. */
567 	if (ic_servaddr != NONE && ic_servaddr != sip)
568 		goto drop_unlock;
569 
570 	/* We have a winner! */
571 	ic_dev = dev;
572 	if (ic_myaddr == NONE)
573 		ic_myaddr = tip;
574 	ic_servaddr = sip;
575 	ic_addrservaddr = sip;
576 	ic_got_reply = IC_RARP;
577 
578 drop_unlock:
579 	/* Show's over.  Nothing to see here.  */
580 	spin_unlock(&ic_recv_lock);
581 
582 drop:
583 	/* Throw the packet out. */
584 	kfree_skb(skb);
585 	return 0;
586 }
587 
588 
589 /*
590  *  Send RARP request packet over a single interface.
591  */
592 static void __init ic_rarp_send_if(struct ic_device *d)
593 {
594 	struct net_device *dev = d->dev;
595 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
596 		 dev->dev_addr, dev->dev_addr);
597 }
598 #endif
599 
600 /*
601  *  Predefine Nameservers
602  */
603 static inline void __init ic_nameservers_predef(void)
604 {
605 	int i;
606 
607 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
608 		ic_nameservers[i] = NONE;
609 }
610 
611 /*
612  *	DHCP/BOOTP support.
613  */
614 
615 #ifdef IPCONFIG_BOOTP
616 
617 struct bootp_pkt {		/* BOOTP packet format */
618 	struct iphdr iph;	/* IP header */
619 	struct udphdr udph;	/* UDP header */
620 	u8 op;			/* 1=request, 2=reply */
621 	u8 htype;		/* HW address type */
622 	u8 hlen;		/* HW address length */
623 	u8 hops;		/* Used only by gateways */
624 	__be32 xid;		/* Transaction ID */
625 	__be16 secs;		/* Seconds since we started */
626 	__be16 flags;		/* Just what it says */
627 	__be32 client_ip;		/* Client's IP address if known */
628 	__be32 your_ip;		/* Assigned IP address */
629 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
630 	__be32 relay_ip;		/* IP address of BOOTP relay */
631 	u8 hw_addr[16];		/* Client's HW address */
632 	u8 serv_name[64];	/* Server host name */
633 	u8 boot_file[128];	/* Name of boot file */
634 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
635 };
636 
637 /* packet ops */
638 #define BOOTP_REQUEST	1
639 #define BOOTP_REPLY	2
640 
641 /* DHCP message types */
642 #define DHCPDISCOVER	1
643 #define DHCPOFFER	2
644 #define DHCPREQUEST	3
645 #define DHCPDECLINE	4
646 #define DHCPACK		5
647 #define DHCPNAK		6
648 #define DHCPRELEASE	7
649 #define DHCPINFORM	8
650 
651 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
652 
653 static struct packet_type bootp_packet_type __initdata = {
654 	.type =	cpu_to_be16(ETH_P_IP),
655 	.func =	ic_bootp_recv,
656 };
657 
658 static __be32 ic_dev_xid;		/* Device under configuration */
659 
660 /*
661  *  Initialize DHCP/BOOTP extension fields in the request.
662  */
663 
664 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
665 
666 #ifdef IPCONFIG_DHCP
667 
668 static void __init
669 ic_dhcp_init_options(u8 *options)
670 {
671 	u8 mt = ((ic_servaddr == NONE)
672 		 ? DHCPDISCOVER : DHCPREQUEST);
673 	u8 *e = options;
674 	int len;
675 
676 	pr_debug("DHCP: Sending message type %d\n", mt);
677 
678 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
679 	e += 4;
680 
681 	*e++ = 53;		/* DHCP message type */
682 	*e++ = 1;
683 	*e++ = mt;
684 
685 	if (mt == DHCPREQUEST) {
686 		*e++ = 54;	/* Server ID (IP address) */
687 		*e++ = 4;
688 		memcpy(e, &ic_servaddr, 4);
689 		e += 4;
690 
691 		*e++ = 50;	/* Requested IP address */
692 		*e++ = 4;
693 		memcpy(e, &ic_myaddr, 4);
694 		e += 4;
695 	}
696 
697 	/* always? */
698 	{
699 		static const u8 ic_req_params[] = {
700 			1,	/* Subnet mask */
701 			3,	/* Default gateway */
702 			6,	/* DNS server */
703 			12,	/* Host name */
704 			15,	/* Domain name */
705 			17,	/* Boot path */
706 			26,	/* MTU */
707 			40,	/* NIS domain name */
708 		};
709 
710 		*e++ = 55;	/* Parameter request list */
711 		*e++ = sizeof(ic_req_params);
712 		memcpy(e, ic_req_params, sizeof(ic_req_params));
713 		e += sizeof(ic_req_params);
714 
715 		if (ic_host_name_set) {
716 			*e++ = 12;	/* host-name */
717 			len = strlen(utsname()->nodename);
718 			*e++ = len;
719 			memcpy(e, utsname()->nodename, len);
720 			e += len;
721 		}
722 		if (*vendor_class_identifier) {
723 			pr_info("DHCP: sending class identifier \"%s\"\n",
724 				vendor_class_identifier);
725 			*e++ = 60;	/* Class-identifier */
726 			len = strlen(vendor_class_identifier);
727 			*e++ = len;
728 			memcpy(e, vendor_class_identifier, len);
729 			e += len;
730 		}
731 		len = strlen(dhcp_client_identifier + 1);
732 		/* the minimum length of identifier is 2, include 1 byte type,
733 		 * and can not be larger than the length of options
734 		 */
735 		if (len >= 1 && len < 312 - (e - options) - 1) {
736 			*e++ = 61;
737 			*e++ = len + 1;
738 			memcpy(e, dhcp_client_identifier, len + 1);
739 			e += len + 1;
740 		}
741 	}
742 
743 	*e++ = 255;	/* End of the list */
744 }
745 
746 #endif /* IPCONFIG_DHCP */
747 
748 static void __init ic_bootp_init_ext(u8 *e)
749 {
750 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
751 	e += 4;
752 	*e++ = 1;		/* Subnet mask request */
753 	*e++ = 4;
754 	e += 4;
755 	*e++ = 3;		/* Default gateway request */
756 	*e++ = 4;
757 	e += 4;
758 	*e++ = 5;		/* Name server request */
759 	*e++ = 8;
760 	e += 8;
761 	*e++ = 12;		/* Host name request */
762 	*e++ = 32;
763 	e += 32;
764 	*e++ = 40;		/* NIS Domain name request */
765 	*e++ = 32;
766 	e += 32;
767 	*e++ = 17;		/* Boot path */
768 	*e++ = 40;
769 	e += 40;
770 
771 	*e++ = 57;		/* set extension buffer size for reply */
772 	*e++ = 2;
773 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
774 	*e++ = 150;
775 
776 	*e++ = 255;		/* End of the list */
777 }
778 
779 
780 /*
781  *  Initialize the DHCP/BOOTP mechanism.
782  */
783 static inline void __init ic_bootp_init(void)
784 {
785 	ic_nameservers_predef();
786 
787 	dev_add_pack(&bootp_packet_type);
788 }
789 
790 
791 /*
792  *  DHCP/BOOTP cleanup.
793  */
794 static inline void __init ic_bootp_cleanup(void)
795 {
796 	dev_remove_pack(&bootp_packet_type);
797 }
798 
799 
800 /*
801  *  Send DHCP/BOOTP request to single interface.
802  */
803 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
804 {
805 	struct net_device *dev = d->dev;
806 	struct sk_buff *skb;
807 	struct bootp_pkt *b;
808 	struct iphdr *h;
809 	int hlen = LL_RESERVED_SPACE(dev);
810 	int tlen = dev->needed_tailroom;
811 
812 	/* Allocate packet */
813 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
814 			GFP_KERNEL);
815 	if (!skb)
816 		return;
817 	skb_reserve(skb, hlen);
818 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
819 	memset(b, 0, sizeof(struct bootp_pkt));
820 
821 	/* Construct IP header */
822 	skb_reset_network_header(skb);
823 	h = ip_hdr(skb);
824 	h->version = 4;
825 	h->ihl = 5;
826 	h->tot_len = htons(sizeof(struct bootp_pkt));
827 	h->frag_off = htons(IP_DF);
828 	h->ttl = 64;
829 	h->protocol = IPPROTO_UDP;
830 	h->daddr = htonl(INADDR_BROADCAST);
831 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
832 
833 	/* Construct UDP header */
834 	b->udph.source = htons(68);
835 	b->udph.dest = htons(67);
836 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
837 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
838 
839 	/* Construct DHCP/BOOTP header */
840 	b->op = BOOTP_REQUEST;
841 	if (dev->type < 256) /* check for false types */
842 		b->htype = dev->type;
843 	else if (dev->type == ARPHRD_FDDI)
844 		b->htype = ARPHRD_ETHER;
845 	else {
846 		pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
847 			dev->name);
848 		b->htype = dev->type; /* can cause undefined behavior */
849 	}
850 
851 	/* server_ip and your_ip address are both already zero per RFC2131 */
852 	b->hlen = dev->addr_len;
853 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
854 	b->secs = htons(jiffies_diff / HZ);
855 	b->xid = d->xid;
856 
857 	/* add DHCP options or BOOTP extensions */
858 #ifdef IPCONFIG_DHCP
859 	if (ic_proto_enabled & IC_USE_DHCP)
860 		ic_dhcp_init_options(b->exten);
861 	else
862 #endif
863 		ic_bootp_init_ext(b->exten);
864 
865 	/* Chain packet down the line... */
866 	skb->dev = dev;
867 	skb->protocol = htons(ETH_P_IP);
868 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
869 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
870 		kfree_skb(skb);
871 		printk("E");
872 		return;
873 	}
874 
875 	if (dev_queue_xmit(skb) < 0)
876 		printk("E");
877 }
878 
879 
880 /*
881  *  Copy BOOTP-supplied string if not already set.
882  */
883 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
884 {
885 	if (!len)
886 		return 0;
887 	if (len > max-1)
888 		len = max-1;
889 	memcpy(dest, src, len);
890 	dest[len] = '\0';
891 	return 1;
892 }
893 
894 
895 /*
896  *  Process BOOTP extensions.
897  */
898 static void __init ic_do_bootp_ext(u8 *ext)
899 {
900 	u8 servers;
901 	int i;
902 	__be16 mtu;
903 
904 	u8 *c;
905 
906 	pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
907 	for (c=ext+2; c<ext+2+ext[1]; c++)
908 		pr_debug(" %02x", *c);
909 	pr_debug("\n");
910 
911 	switch (*ext++) {
912 	case 1:		/* Subnet mask */
913 		if (ic_netmask == NONE)
914 			memcpy(&ic_netmask, ext+1, 4);
915 		break;
916 	case 3:		/* Default gateway */
917 		if (ic_gateway == NONE)
918 			memcpy(&ic_gateway, ext+1, 4);
919 		break;
920 	case 6:		/* DNS server */
921 		servers= *ext/4;
922 		if (servers > CONF_NAMESERVERS_MAX)
923 			servers = CONF_NAMESERVERS_MAX;
924 		for (i = 0; i < servers; i++) {
925 			if (ic_nameservers[i] == NONE)
926 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
927 		}
928 		break;
929 	case 12:	/* Host name */
930 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
931 				__NEW_UTS_LEN);
932 		ic_host_name_set = 1;
933 		break;
934 	case 15:	/* Domain name (DNS) */
935 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
936 		break;
937 	case 17:	/* Root path */
938 		if (!root_server_path[0])
939 			ic_bootp_string(root_server_path, ext+1, *ext,
940 					sizeof(root_server_path));
941 		break;
942 	case 26:	/* Interface MTU */
943 		memcpy(&mtu, ext+1, sizeof(mtu));
944 		ic_dev_mtu = ntohs(mtu);
945 		break;
946 	case 40:	/* NIS Domain name (_not_ DNS) */
947 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
948 				__NEW_UTS_LEN);
949 		break;
950 	}
951 }
952 
953 
954 /*
955  *  Receive BOOTP reply.
956  */
957 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
958 {
959 	struct bootp_pkt *b;
960 	struct iphdr *h;
961 	struct ic_device *d;
962 	int len, ext_len;
963 
964 	if (!net_eq(dev_net(dev), &init_net))
965 		goto drop;
966 
967 	/* Perform verifications before taking the lock.  */
968 	if (skb->pkt_type == PACKET_OTHERHOST)
969 		goto drop;
970 
971 	skb = skb_share_check(skb, GFP_ATOMIC);
972 	if (!skb)
973 		return NET_RX_DROP;
974 
975 	if (!pskb_may_pull(skb,
976 			   sizeof(struct iphdr) +
977 			   sizeof(struct udphdr)))
978 		goto drop;
979 
980 	b = (struct bootp_pkt *)skb_network_header(skb);
981 	h = &b->iph;
982 
983 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
984 		goto drop;
985 
986 	/* Fragments are not supported */
987 	if (ip_is_fragment(h)) {
988 		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
989 		goto drop;
990 	}
991 
992 	if (skb->len < ntohs(h->tot_len))
993 		goto drop;
994 
995 	if (ip_fast_csum((char *) h, h->ihl))
996 		goto drop;
997 
998 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
999 		goto drop;
1000 
1001 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1002 		goto drop;
1003 
1004 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
1005 	ext_len = len - (sizeof(*b) -
1006 			 sizeof(struct iphdr) -
1007 			 sizeof(struct udphdr) -
1008 			 sizeof(b->exten));
1009 	if (ext_len < 0)
1010 		goto drop;
1011 
1012 	/* Ok the front looks good, make sure we can get at the rest.  */
1013 	if (!pskb_may_pull(skb, skb->len))
1014 		goto drop;
1015 
1016 	b = (struct bootp_pkt *)skb_network_header(skb);
1017 	h = &b->iph;
1018 
1019 	/* One reply at a time, please. */
1020 	spin_lock(&ic_recv_lock);
1021 
1022 	/* If we already have a reply, just drop the packet */
1023 	if (ic_got_reply)
1024 		goto drop_unlock;
1025 
1026 	/* Find the ic_device that the packet arrived on */
1027 	d = ic_first_dev;
1028 	while (d && d->dev != dev)
1029 		d = d->next;
1030 	if (!d)
1031 		goto drop_unlock;  /* should never happen */
1032 
1033 	/* Is it a reply to our BOOTP request? */
1034 	if (b->op != BOOTP_REPLY ||
1035 	    b->xid != d->xid) {
1036 		net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1037 				    b->op, b->xid);
1038 		goto drop_unlock;
1039 	}
1040 
1041 	/* Is it a reply for the device we are configuring? */
1042 	if (b->xid != ic_dev_xid) {
1043 		net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1044 		goto drop_unlock;
1045 	}
1046 
1047 	/* Parse extensions */
1048 	if (ext_len >= 4 &&
1049 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1050 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1051 		u8 *ext;
1052 
1053 #ifdef IPCONFIG_DHCP
1054 		if (ic_proto_enabled & IC_USE_DHCP) {
1055 			__be32 server_id = NONE;
1056 			int mt = 0;
1057 
1058 			ext = &b->exten[4];
1059 			while (ext < end && *ext != 0xff) {
1060 				u8 *opt = ext++;
1061 				if (*opt == 0)	/* Padding */
1062 					continue;
1063 				ext += *ext + 1;
1064 				if (ext >= end)
1065 					break;
1066 				switch (*opt) {
1067 				case 53:	/* Message type */
1068 					if (opt[1])
1069 						mt = opt[2];
1070 					break;
1071 				case 54:	/* Server ID (IP address) */
1072 					if (opt[1] >= 4)
1073 						memcpy(&server_id, opt + 2, 4);
1074 					break;
1075 				}
1076 			}
1077 
1078 			pr_debug("DHCP: Got message type %d\n", mt);
1079 
1080 			switch (mt) {
1081 			case DHCPOFFER:
1082 				/* While in the process of accepting one offer,
1083 				 * ignore all others.
1084 				 */
1085 				if (ic_myaddr != NONE)
1086 					goto drop_unlock;
1087 
1088 				/* Let's accept that offer. */
1089 				ic_myaddr = b->your_ip;
1090 				ic_servaddr = server_id;
1091 				pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1092 					 &ic_myaddr, &b->iph.saddr);
1093 				/* The DHCP indicated server address takes
1094 				 * precedence over the bootp header one if
1095 				 * they are different.
1096 				 */
1097 				if ((server_id != NONE) &&
1098 				    (b->server_ip != server_id))
1099 					b->server_ip = ic_servaddr;
1100 				break;
1101 
1102 			case DHCPACK:
1103 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1104 					goto drop_unlock;
1105 
1106 				/* Yeah! */
1107 				break;
1108 
1109 			default:
1110 				/* Urque.  Forget it*/
1111 				ic_myaddr = NONE;
1112 				ic_servaddr = NONE;
1113 				goto drop_unlock;
1114 			}
1115 
1116 			ic_dhcp_msgtype = mt;
1117 
1118 		}
1119 #endif /* IPCONFIG_DHCP */
1120 
1121 		ext = &b->exten[4];
1122 		while (ext < end && *ext != 0xff) {
1123 			u8 *opt = ext++;
1124 			if (*opt == 0)	/* Padding */
1125 				continue;
1126 			ext += *ext + 1;
1127 			if (ext < end)
1128 				ic_do_bootp_ext(opt);
1129 		}
1130 	}
1131 
1132 	/* We have a winner! */
1133 	ic_dev = dev;
1134 	ic_myaddr = b->your_ip;
1135 	ic_servaddr = b->server_ip;
1136 	ic_addrservaddr = b->iph.saddr;
1137 	if (ic_gateway == NONE && b->relay_ip)
1138 		ic_gateway = b->relay_ip;
1139 	if (ic_nameservers[0] == NONE)
1140 		ic_nameservers[0] = ic_servaddr;
1141 	ic_got_reply = IC_BOOTP;
1142 
1143 drop_unlock:
1144 	/* Show's over.  Nothing to see here.  */
1145 	spin_unlock(&ic_recv_lock);
1146 
1147 drop:
1148 	/* Throw the packet out. */
1149 	kfree_skb(skb);
1150 
1151 	return 0;
1152 }
1153 
1154 
1155 #endif
1156 
1157 
1158 /*
1159  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1160  */
1161 
1162 #ifdef IPCONFIG_DYNAMIC
1163 
1164 static int __init ic_dynamic(void)
1165 {
1166 	int retries;
1167 	struct ic_device *d;
1168 	unsigned long start_jiffies, timeout, jiff;
1169 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1170 	int do_rarp = ic_proto_have_if & IC_RARP;
1171 
1172 	/*
1173 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1174 	 * This routine gets only called when some pieces of information
1175 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1176 	 */
1177 	if (!ic_proto_enabled) {
1178 		pr_err("IP-Config: Incomplete network configuration information\n");
1179 		return -1;
1180 	}
1181 
1182 #ifdef IPCONFIG_BOOTP
1183 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1184 		pr_err("DHCP/BOOTP: No suitable device found\n");
1185 #endif
1186 #ifdef IPCONFIG_RARP
1187 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1188 		pr_err("RARP: No suitable device found\n");
1189 #endif
1190 
1191 	if (!ic_proto_have_if)
1192 		/* Error message already printed */
1193 		return -1;
1194 
1195 	/*
1196 	 * Setup protocols
1197 	 */
1198 #ifdef IPCONFIG_BOOTP
1199 	if (do_bootp)
1200 		ic_bootp_init();
1201 #endif
1202 #ifdef IPCONFIG_RARP
1203 	if (do_rarp)
1204 		ic_rarp_init();
1205 #endif
1206 
1207 	/*
1208 	 * Send requests and wait, until we get an answer. This loop
1209 	 * seems to be a terrible waste of CPU time, but actually there is
1210 	 * only one process running at all, so we don't need to use any
1211 	 * scheduler functions.
1212 	 * [Actually we could now, but the nothing else running note still
1213 	 *  applies.. - AC]
1214 	 */
1215 	pr_notice("Sending %s%s%s requests .",
1216 		  do_bootp
1217 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1218 		  (do_bootp && do_rarp) ? " and " : "",
1219 		  do_rarp ? "RARP" : "");
1220 
1221 	start_jiffies = jiffies;
1222 	d = ic_first_dev;
1223 	retries = CONF_SEND_RETRIES;
1224 	get_random_bytes(&timeout, sizeof(timeout));
1225 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1226 	for (;;) {
1227 #ifdef IPCONFIG_BOOTP
1228 		/* Track the device we are configuring */
1229 		ic_dev_xid = d->xid;
1230 
1231 		if (do_bootp && (d->able & IC_BOOTP))
1232 			ic_bootp_send_if(d, jiffies - start_jiffies);
1233 #endif
1234 #ifdef IPCONFIG_RARP
1235 		if (do_rarp && (d->able & IC_RARP))
1236 			ic_rarp_send_if(d);
1237 #endif
1238 
1239 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1240 		while (time_before(jiffies, jiff) && !ic_got_reply)
1241 			schedule_timeout_uninterruptible(1);
1242 #ifdef IPCONFIG_DHCP
1243 		/* DHCP isn't done until we get a DHCPACK. */
1244 		if ((ic_got_reply & IC_BOOTP) &&
1245 		    (ic_proto_enabled & IC_USE_DHCP) &&
1246 		    ic_dhcp_msgtype != DHCPACK) {
1247 			ic_got_reply = 0;
1248 			pr_cont(",");
1249 			continue;
1250 		}
1251 #endif /* IPCONFIG_DHCP */
1252 
1253 		if (ic_got_reply) {
1254 			pr_cont(" OK\n");
1255 			break;
1256 		}
1257 
1258 		if ((d = d->next))
1259 			continue;
1260 
1261 		if (! --retries) {
1262 			pr_cont(" timed out!\n");
1263 			break;
1264 		}
1265 
1266 		d = ic_first_dev;
1267 
1268 		timeout = timeout CONF_TIMEOUT_MULT;
1269 		if (timeout > CONF_TIMEOUT_MAX)
1270 			timeout = CONF_TIMEOUT_MAX;
1271 
1272 		pr_cont(".");
1273 	}
1274 
1275 #ifdef IPCONFIG_BOOTP
1276 	if (do_bootp)
1277 		ic_bootp_cleanup();
1278 #endif
1279 #ifdef IPCONFIG_RARP
1280 	if (do_rarp)
1281 		ic_rarp_cleanup();
1282 #endif
1283 
1284 	if (!ic_got_reply) {
1285 		ic_myaddr = NONE;
1286 		return -1;
1287 	}
1288 
1289 	pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1290 		((ic_got_reply & IC_RARP) ? "RARP"
1291 		: (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1292 		&ic_addrservaddr, &ic_myaddr);
1293 
1294 	return 0;
1295 }
1296 
1297 #endif /* IPCONFIG_DYNAMIC */
1298 
1299 #ifdef CONFIG_PROC_FS
1300 
1301 static int pnp_seq_show(struct seq_file *seq, void *v)
1302 {
1303 	int i;
1304 
1305 	if (ic_proto_used & IC_PROTO)
1306 		seq_printf(seq, "#PROTO: %s\n",
1307 			   (ic_proto_used & IC_RARP) ? "RARP"
1308 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1309 	else
1310 		seq_puts(seq, "#MANUAL\n");
1311 
1312 	if (ic_domain[0])
1313 		seq_printf(seq,
1314 			   "domain %s\n", ic_domain);
1315 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1316 		if (ic_nameservers[i] != NONE)
1317 			seq_printf(seq, "nameserver %pI4\n",
1318 				   &ic_nameservers[i]);
1319 	}
1320 	if (ic_servaddr != NONE)
1321 		seq_printf(seq, "bootserver %pI4\n",
1322 			   &ic_servaddr);
1323 	return 0;
1324 }
1325 
1326 static int pnp_seq_open(struct inode *indoe, struct file *file)
1327 {
1328 	return single_open(file, pnp_seq_show, NULL);
1329 }
1330 
1331 static const struct file_operations pnp_seq_fops = {
1332 	.owner		= THIS_MODULE,
1333 	.open		= pnp_seq_open,
1334 	.read		= seq_read,
1335 	.llseek		= seq_lseek,
1336 	.release	= single_release,
1337 };
1338 #endif /* CONFIG_PROC_FS */
1339 
1340 /*
1341  *  Extract IP address from the parameter string if needed. Note that we
1342  *  need to have root_server_addr set _before_ IPConfig gets called as it
1343  *  can override it.
1344  */
1345 __be32 __init root_nfs_parse_addr(char *name)
1346 {
1347 	__be32 addr;
1348 	int octets = 0;
1349 	char *cp, *cq;
1350 
1351 	cp = cq = name;
1352 	while (octets < 4) {
1353 		while (*cp >= '0' && *cp <= '9')
1354 			cp++;
1355 		if (cp == cq || cp - cq > 3)
1356 			break;
1357 		if (*cp == '.' || octets == 3)
1358 			octets++;
1359 		if (octets < 4)
1360 			cp++;
1361 		cq = cp;
1362 	}
1363 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1364 		if (*cp == ':')
1365 			*cp++ = '\0';
1366 		addr = in_aton(name);
1367 		memmove(name, cp, strlen(cp) + 1);
1368 	} else
1369 		addr = NONE;
1370 
1371 	return addr;
1372 }
1373 
1374 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1375 
1376 static int __init wait_for_devices(void)
1377 {
1378 	int i;
1379 
1380 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1381 		struct net_device *dev;
1382 		int found = 0;
1383 
1384 		rtnl_lock();
1385 		for_each_netdev(&init_net, dev) {
1386 			if (ic_is_init_dev(dev)) {
1387 				found = 1;
1388 				break;
1389 			}
1390 		}
1391 		rtnl_unlock();
1392 		if (found)
1393 			return 0;
1394 		ssleep(1);
1395 	}
1396 	return -ENODEV;
1397 }
1398 
1399 /*
1400  *	IP Autoconfig dispatcher.
1401  */
1402 
1403 static int __init ip_auto_config(void)
1404 {
1405 	__be32 addr;
1406 #ifdef IPCONFIG_DYNAMIC
1407 	int retries = CONF_OPEN_RETRIES;
1408 #endif
1409 	int err;
1410 	unsigned int i;
1411 
1412 #ifdef CONFIG_PROC_FS
1413 	proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1414 #endif /* CONFIG_PROC_FS */
1415 
1416 	if (!ic_enable)
1417 		return 0;
1418 
1419 	pr_debug("IP-Config: Entered.\n");
1420 #ifdef IPCONFIG_DYNAMIC
1421  try_try_again:
1422 #endif
1423 	/* Wait for devices to appear */
1424 	err = wait_for_devices();
1425 	if (err)
1426 		return err;
1427 
1428 	/* Setup all network devices */
1429 	err = ic_open_devs();
1430 	if (err)
1431 		return err;
1432 
1433 	/* Give drivers a chance to settle */
1434 	msleep(CONF_POST_OPEN);
1435 
1436 	/*
1437 	 * If the config information is insufficient (e.g., our IP address or
1438 	 * IP address of the boot server is missing or we have multiple network
1439 	 * interfaces and no default was set), use BOOTP or RARP to get the
1440 	 * missing values.
1441 	 */
1442 	if (ic_myaddr == NONE ||
1443 #ifdef CONFIG_ROOT_NFS
1444 	    (root_server_addr == NONE &&
1445 	     ic_servaddr == NONE &&
1446 	     ROOT_DEV == Root_NFS) ||
1447 #endif
1448 	    ic_first_dev->next) {
1449 #ifdef IPCONFIG_DYNAMIC
1450 		if (ic_dynamic() < 0) {
1451 			ic_close_devs();
1452 
1453 			/*
1454 			 * I don't know why, but sometimes the
1455 			 * eepro100 driver (at least) gets upset and
1456 			 * doesn't work the first time it's opened.
1457 			 * But then if you close it and reopen it, it
1458 			 * works just fine.  So we need to try that at
1459 			 * least once before giving up.
1460 			 *
1461 			 * Also, if the root will be NFS-mounted, we
1462 			 * have nowhere to go if DHCP fails.  So we
1463 			 * just have to keep trying forever.
1464 			 *
1465 			 * 				-- Chip
1466 			 */
1467 #ifdef CONFIG_ROOT_NFS
1468 			if (ROOT_DEV ==  Root_NFS) {
1469 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1470 				goto try_try_again;
1471 			}
1472 #endif
1473 
1474 			if (--retries) {
1475 				pr_err("IP-Config: Reopening network devices...\n");
1476 				goto try_try_again;
1477 			}
1478 
1479 			/* Oh, well.  At least we tried. */
1480 			pr_err("IP-Config: Auto-configuration of network failed\n");
1481 			return -1;
1482 		}
1483 #else /* !DYNAMIC */
1484 		pr_err("IP-Config: Incomplete network configuration information\n");
1485 		ic_close_devs();
1486 		return -1;
1487 #endif /* IPCONFIG_DYNAMIC */
1488 	} else {
1489 		/* Device selected manually or only one device -> use it */
1490 		ic_dev = ic_first_dev->dev;
1491 	}
1492 
1493 	addr = root_nfs_parse_addr(root_server_path);
1494 	if (root_server_addr == NONE)
1495 		root_server_addr = addr;
1496 
1497 	/*
1498 	 * Use defaults wherever applicable.
1499 	 */
1500 	if (ic_defaults() < 0)
1501 		return -1;
1502 
1503 	/*
1504 	 * Close all network devices except the device we've
1505 	 * autoconfigured and set up routes.
1506 	 */
1507 	ic_close_devs();
1508 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1509 		return -1;
1510 
1511 	/*
1512 	 * Record which protocol was actually used.
1513 	 */
1514 #ifdef IPCONFIG_DYNAMIC
1515 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1516 #endif
1517 
1518 #ifndef IPCONFIG_SILENT
1519 	/*
1520 	 * Clue in the operator.
1521 	 */
1522 	pr_info("IP-Config: Complete:\n");
1523 
1524 	pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1525 		ic_dev->name, ic_dev->addr_len, ic_dev->dev_addr,
1526 		&ic_myaddr, &ic_netmask, &ic_gateway);
1527 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1528 		utsname()->nodename, ic_domain, utsname()->domainname);
1529 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1530 		&ic_servaddr, &root_server_addr, root_server_path);
1531 	if (ic_dev_mtu)
1532 		pr_cont(", mtu=%d", ic_dev_mtu);
1533 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1534 		if (ic_nameservers[i] != NONE) {
1535 			pr_cont("     nameserver%u=%pI4",
1536 				i, &ic_nameservers[i]);
1537 			break;
1538 		}
1539 	for (i++; i < CONF_NAMESERVERS_MAX; i++)
1540 		if (ic_nameservers[i] != NONE)
1541 			pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1542 	pr_cont("\n");
1543 #endif /* !SILENT */
1544 
1545 	return 0;
1546 }
1547 
1548 late_initcall(ip_auto_config);
1549 
1550 
1551 /*
1552  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1553  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1554  */
1555 static int __init ic_proto_name(char *name)
1556 {
1557 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1558 		return 1;
1559 	}
1560 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1561 		return 0;
1562 	}
1563 #ifdef CONFIG_IP_PNP_DHCP
1564 	else if (!strncmp(name, "dhcp", 4)) {
1565 		char *client_id;
1566 
1567 		ic_proto_enabled &= ~IC_RARP;
1568 		client_id = strstr(name, "dhcp,");
1569 		if (client_id) {
1570 			char *v;
1571 
1572 			client_id = client_id + 5;
1573 			v = strchr(client_id, ',');
1574 			if (!v)
1575 				return 1;
1576 			*v = 0;
1577 			if (kstrtou8(client_id, 0, dhcp_client_identifier))
1578 				pr_debug("DHCP: Invalid client identifier type\n");
1579 			strncpy(dhcp_client_identifier + 1, v + 1, 251);
1580 			*v = ',';
1581 		}
1582 		return 1;
1583 	}
1584 #endif
1585 #ifdef CONFIG_IP_PNP_BOOTP
1586 	else if (!strcmp(name, "bootp")) {
1587 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1588 		return 1;
1589 	}
1590 #endif
1591 #ifdef CONFIG_IP_PNP_RARP
1592 	else if (!strcmp(name, "rarp")) {
1593 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1594 		return 1;
1595 	}
1596 #endif
1597 #ifdef IPCONFIG_DYNAMIC
1598 	else if (!strcmp(name, "both")) {
1599 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1600 		return 1;
1601 	}
1602 #endif
1603 	return 0;
1604 }
1605 
1606 static int __init ip_auto_config_setup(char *addrs)
1607 {
1608 	char *cp, *ip, *dp;
1609 	int num = 0;
1610 
1611 	ic_set_manually = 1;
1612 	ic_enable = 1;
1613 
1614 	/*
1615 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1616 	 * and skip the below static IP processing.
1617 	 */
1618 	if (ic_proto_name(addrs))
1619 		return 1;
1620 
1621 	/* If no static IP is given, turn off autoconfig and bail.  */
1622 	if (*addrs == 0 ||
1623 	    strcmp(addrs, "off") == 0 ||
1624 	    strcmp(addrs, "none") == 0) {
1625 		ic_enable = 0;
1626 		return 1;
1627 	}
1628 
1629 	ic_nameservers_predef();
1630 
1631 	/* Parse string for static IP assignment.  */
1632 	ip = addrs;
1633 	while (ip && *ip) {
1634 		if ((cp = strchr(ip, ':')))
1635 			*cp++ = '\0';
1636 		if (strlen(ip) > 0) {
1637 			pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1638 			switch (num) {
1639 			case 0:
1640 				if ((ic_myaddr = in_aton(ip)) == ANY)
1641 					ic_myaddr = NONE;
1642 				break;
1643 			case 1:
1644 				if ((ic_servaddr = in_aton(ip)) == ANY)
1645 					ic_servaddr = NONE;
1646 				break;
1647 			case 2:
1648 				if ((ic_gateway = in_aton(ip)) == ANY)
1649 					ic_gateway = NONE;
1650 				break;
1651 			case 3:
1652 				if ((ic_netmask = in_aton(ip)) == ANY)
1653 					ic_netmask = NONE;
1654 				break;
1655 			case 4:
1656 				if ((dp = strchr(ip, '.'))) {
1657 					*dp++ = '\0';
1658 					strlcpy(utsname()->domainname, dp,
1659 						sizeof(utsname()->domainname));
1660 				}
1661 				strlcpy(utsname()->nodename, ip,
1662 					sizeof(utsname()->nodename));
1663 				ic_host_name_set = 1;
1664 				break;
1665 			case 5:
1666 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1667 				break;
1668 			case 6:
1669 				if (ic_proto_name(ip) == 0 &&
1670 				    ic_myaddr == NONE) {
1671 					ic_enable = 0;
1672 				}
1673 				break;
1674 			case 7:
1675 				if (CONF_NAMESERVERS_MAX >= 1) {
1676 					ic_nameservers[0] = in_aton(ip);
1677 					if (ic_nameservers[0] == ANY)
1678 						ic_nameservers[0] = NONE;
1679 				}
1680 				break;
1681 			case 8:
1682 				if (CONF_NAMESERVERS_MAX >= 2) {
1683 					ic_nameservers[1] = in_aton(ip);
1684 					if (ic_nameservers[1] == ANY)
1685 						ic_nameservers[1] = NONE;
1686 				}
1687 				break;
1688 			}
1689 		}
1690 		ip = cp;
1691 		num++;
1692 	}
1693 
1694 	return 1;
1695 }
1696 __setup("ip=", ip_auto_config_setup);
1697 
1698 static int __init nfsaddrs_config_setup(char *addrs)
1699 {
1700 	return ip_auto_config_setup(addrs);
1701 }
1702 __setup("nfsaddrs=", nfsaddrs_config_setup);
1703 
1704 static int __init vendor_class_identifier_setup(char *addrs)
1705 {
1706 	if (strlcpy(vendor_class_identifier, addrs,
1707 		    sizeof(vendor_class_identifier))
1708 	    >= sizeof(vendor_class_identifier))
1709 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1710 			vendor_class_identifier);
1711 	return 1;
1712 }
1713 __setup("dhcpclass=", vendor_class_identifier_setup);
1714