xref: /openbmc/linux/net/ipv4/ipconfig.c (revision cfbb9be8)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
4  *  user-supplied information to configure own IP address and routes.
5  *
6  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
7  *
8  *  Derived from network configuration code in fs/nfs/nfsroot.c,
9  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
10  *
11  *  BOOTP rewritten to construct and analyse packets itself instead
12  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
13  *					     -- MJ, December 1998
14  *
15  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
16  *  initialization scheme.
17  *	- Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
18  *
19  *  DHCP support added.  To users this looks like a whole separate
20  *  protocol, but we know it's just a bag on the side of BOOTP.
21  *		-- Chip Salzenberg <chip@valinux.com>, May 2000
22  *
23  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
24  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
25  *
26  *  Merged changes from 2.2.19 into 2.4.3
27  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
28  *
29  *  Multiple Nameservers in /proc/net/pnp
30  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
31  */
32 
33 #include <linux/types.h>
34 #include <linux/string.h>
35 #include <linux/kernel.h>
36 #include <linux/jiffies.h>
37 #include <linux/random.h>
38 #include <linux/init.h>
39 #include <linux/utsname.h>
40 #include <linux/in.h>
41 #include <linux/if.h>
42 #include <linux/inet.h>
43 #include <linux/inetdevice.h>
44 #include <linux/netdevice.h>
45 #include <linux/if_arp.h>
46 #include <linux/skbuff.h>
47 #include <linux/ip.h>
48 #include <linux/socket.h>
49 #include <linux/route.h>
50 #include <linux/udp.h>
51 #include <linux/proc_fs.h>
52 #include <linux/seq_file.h>
53 #include <linux/major.h>
54 #include <linux/root_dev.h>
55 #include <linux/delay.h>
56 #include <linux/nfs_fs.h>
57 #include <linux/slab.h>
58 #include <linux/export.h>
59 #include <net/net_namespace.h>
60 #include <net/arp.h>
61 #include <net/dsa.h>
62 #include <net/ip.h>
63 #include <net/ipconfig.h>
64 #include <net/route.h>
65 
66 #include <linux/uaccess.h>
67 #include <net/checksum.h>
68 #include <asm/processor.h>
69 
70 #if defined(CONFIG_IP_PNP_DHCP)
71 #define IPCONFIG_DHCP
72 #endif
73 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
74 #define IPCONFIG_BOOTP
75 #endif
76 #if defined(CONFIG_IP_PNP_RARP)
77 #define IPCONFIG_RARP
78 #endif
79 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
80 #define IPCONFIG_DYNAMIC
81 #endif
82 
83 /* Define the friendly delay before and after opening net devices */
84 #define CONF_POST_OPEN		10	/* After opening: 10 msecs */
85 #define CONF_CARRIER_TIMEOUT	120000	/* Wait for carrier timeout */
86 
87 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
88 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
89 #define CONF_SEND_RETRIES 	6	/* Send six requests per open */
90 #define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
91 #define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
92 #define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
93 #define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
94 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
95 					   - '3' from resolv.h */
96 
97 #define NONE cpu_to_be32(INADDR_NONE)
98 #define ANY cpu_to_be32(INADDR_ANY)
99 
100 /*
101  * Public IP configuration
102  */
103 
104 /* This is used by platforms which might be able to set the ipconfig
105  * variables using firmware environment vars.  If this is set, it will
106  * ignore such firmware variables.
107  */
108 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
109 
110 static int ic_enable __initdata;		/* IP config enabled? */
111 
112 /* Protocol choice */
113 int ic_proto_enabled __initdata = 0
114 #ifdef IPCONFIG_BOOTP
115 			| IC_BOOTP
116 #endif
117 #ifdef CONFIG_IP_PNP_DHCP
118 			| IC_USE_DHCP
119 #endif
120 #ifdef IPCONFIG_RARP
121 			| IC_RARP
122 #endif
123 			;
124 
125 static int ic_host_name_set __initdata;	/* Host name set by us? */
126 
127 __be32 ic_myaddr = NONE;		/* My IP address */
128 static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
129 __be32 ic_gateway = NONE;	/* Gateway IP address */
130 
131 #ifdef IPCONFIG_DYNAMIC
132 static __be32 ic_addrservaddr = NONE;	/* IP Address of the IP addresses'server */
133 #endif
134 
135 __be32 ic_servaddr = NONE;	/* Boot server IP address */
136 
137 __be32 root_server_addr = NONE;	/* Address of NFS server */
138 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
139 
140 /* vendor class identifier */
141 static char vendor_class_identifier[253] __initdata;
142 
143 #if defined(CONFIG_IP_PNP_DHCP)
144 static char dhcp_client_identifier[253] __initdata;
145 #endif
146 
147 /* Persistent data: */
148 
149 #ifdef IPCONFIG_DYNAMIC
150 static int ic_proto_used;			/* Protocol used, if any */
151 #else
152 #define ic_proto_used 0
153 #endif
154 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
155 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
156 
157 /*
158  * Private state.
159  */
160 
161 /* Name of user-selected boot device */
162 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
163 
164 /* Protocols supported by available interfaces */
165 static int ic_proto_have_if __initdata;
166 
167 /* MTU for boot device */
168 static int ic_dev_mtu __initdata;
169 
170 #ifdef IPCONFIG_DYNAMIC
171 static DEFINE_SPINLOCK(ic_recv_lock);
172 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
173 #endif
174 #ifdef IPCONFIG_DHCP
175 static int ic_dhcp_msgtype __initdata;	/* DHCP msg type received */
176 #endif
177 
178 
179 /*
180  *	Network devices
181  */
182 
183 struct ic_device {
184 	struct ic_device *next;
185 	struct net_device *dev;
186 	unsigned short flags;
187 	short able;
188 	__be32 xid;
189 };
190 
191 static struct ic_device *ic_first_dev __initdata;	/* List of open device */
192 static struct ic_device *ic_dev __initdata;		/* Selected device */
193 
194 static bool __init ic_is_init_dev(struct net_device *dev)
195 {
196 	if (dev->flags & IFF_LOOPBACK)
197 		return false;
198 	return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
199 	    (!(dev->flags & IFF_LOOPBACK) &&
200 	     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
201 	     strncmp(dev->name, "dummy", 5));
202 }
203 
204 static int __init ic_open_devs(void)
205 {
206 	struct ic_device *d, **last;
207 	struct net_device *dev;
208 	unsigned short oflags;
209 	unsigned long start, next_msg;
210 
211 	last = &ic_first_dev;
212 	rtnl_lock();
213 
214 	/* bring loopback and DSA master network devices up first */
215 	for_each_netdev(&init_net, dev) {
216 		if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
217 			continue;
218 		if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
219 			pr_err("IP-Config: Failed to open %s\n", dev->name);
220 	}
221 
222 	for_each_netdev(&init_net, dev) {
223 		if (ic_is_init_dev(dev)) {
224 			int able = 0;
225 			if (dev->mtu >= 364)
226 				able |= IC_BOOTP;
227 			else
228 				pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
229 					dev->name, dev->mtu);
230 			if (!(dev->flags & IFF_NOARP))
231 				able |= IC_RARP;
232 			able &= ic_proto_enabled;
233 			if (ic_proto_enabled && !able)
234 				continue;
235 			oflags = dev->flags;
236 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
237 				pr_err("IP-Config: Failed to open %s\n",
238 				       dev->name);
239 				continue;
240 			}
241 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
242 				rtnl_unlock();
243 				return -ENOMEM;
244 			}
245 			d->dev = dev;
246 			*last = d;
247 			last = &d->next;
248 			d->flags = oflags;
249 			d->able = able;
250 			if (able & IC_BOOTP)
251 				get_random_bytes(&d->xid, sizeof(__be32));
252 			else
253 				d->xid = 0;
254 			ic_proto_have_if |= able;
255 			pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
256 				 dev->name, able, d->xid);
257 		}
258 	}
259 
260 	/* no point in waiting if we could not bring up at least one device */
261 	if (!ic_first_dev)
262 		goto have_carrier;
263 
264 	/* wait for a carrier on at least one device */
265 	start = jiffies;
266 	next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
267 	while (time_before(jiffies, start +
268 			   msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
269 		int wait, elapsed;
270 
271 		for_each_netdev(&init_net, dev)
272 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
273 				goto have_carrier;
274 
275 		msleep(1);
276 
277 		if (time_before(jiffies, next_msg))
278 			continue;
279 
280 		elapsed = jiffies_to_msecs(jiffies - start);
281 		wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
282 		pr_info("Waiting up to %d more seconds for network.\n", wait);
283 		next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
284 	}
285 have_carrier:
286 	rtnl_unlock();
287 
288 	*last = NULL;
289 
290 	if (!ic_first_dev) {
291 		if (user_dev_name[0])
292 			pr_err("IP-Config: Device `%s' not found\n",
293 			       user_dev_name);
294 		else
295 			pr_err("IP-Config: No network devices available\n");
296 		return -ENODEV;
297 	}
298 	return 0;
299 }
300 
301 static void __init ic_close_devs(void)
302 {
303 	struct ic_device *d, *next;
304 	struct net_device *dev;
305 
306 	rtnl_lock();
307 	next = ic_first_dev;
308 	while ((d = next)) {
309 		next = d->next;
310 		dev = d->dev;
311 		if (d != ic_dev && !netdev_uses_dsa(dev)) {
312 			pr_debug("IP-Config: Downing %s\n", dev->name);
313 			dev_change_flags(dev, d->flags);
314 		}
315 		kfree(d);
316 	}
317 	rtnl_unlock();
318 }
319 
320 /*
321  *	Interface to various network functions.
322  */
323 
324 static inline void
325 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
326 {
327 	sin->sin_family = AF_INET;
328 	sin->sin_addr.s_addr = addr;
329 	sin->sin_port = port;
330 }
331 
332 /*
333  *	Set up interface addresses and routes.
334  */
335 
336 static int __init ic_setup_if(void)
337 {
338 	struct ifreq ir;
339 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
340 	int err;
341 
342 	memset(&ir, 0, sizeof(ir));
343 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
344 	set_sockaddr(sin, ic_myaddr, 0);
345 	if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) {
346 		pr_err("IP-Config: Unable to set interface address (%d)\n",
347 		       err);
348 		return -1;
349 	}
350 	set_sockaddr(sin, ic_netmask, 0);
351 	if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) {
352 		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
353 		       err);
354 		return -1;
355 	}
356 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
357 	if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) {
358 		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
359 		       err);
360 		return -1;
361 	}
362 	/* Handle the case where we need non-standard MTU on the boot link (a network
363 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
364 	 * out, we'll try to muddle along.
365 	 */
366 	if (ic_dev_mtu != 0) {
367 		rtnl_lock();
368 		if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0)
369 			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
370 			       ic_dev_mtu, err);
371 		rtnl_unlock();
372 	}
373 	return 0;
374 }
375 
376 static int __init ic_setup_routes(void)
377 {
378 	/* No need to setup device routes, only the default route... */
379 
380 	if (ic_gateway != NONE) {
381 		struct rtentry rm;
382 		int err;
383 
384 		memset(&rm, 0, sizeof(rm));
385 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
386 			pr_err("IP-Config: Gateway not on directly connected network\n");
387 			return -1;
388 		}
389 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
390 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
391 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
392 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
393 		if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) {
394 			pr_err("IP-Config: Cannot add default route (%d)\n",
395 			       err);
396 			return -1;
397 		}
398 	}
399 
400 	return 0;
401 }
402 
403 /*
404  *	Fill in default values for all missing parameters.
405  */
406 
407 static int __init ic_defaults(void)
408 {
409 	/*
410 	 *	At this point we have no userspace running so need not
411 	 *	claim locks on system_utsname
412 	 */
413 
414 	if (!ic_host_name_set)
415 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
416 
417 	if (root_server_addr == NONE)
418 		root_server_addr = ic_servaddr;
419 
420 	if (ic_netmask == NONE) {
421 		if (IN_CLASSA(ntohl(ic_myaddr)))
422 			ic_netmask = htonl(IN_CLASSA_NET);
423 		else if (IN_CLASSB(ntohl(ic_myaddr)))
424 			ic_netmask = htonl(IN_CLASSB_NET);
425 		else if (IN_CLASSC(ntohl(ic_myaddr)))
426 			ic_netmask = htonl(IN_CLASSC_NET);
427 		else {
428 			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
429 			       &ic_myaddr);
430 			return -1;
431 		}
432 		pr_notice("IP-Config: Guessing netmask %pI4\n",
433 			  &ic_netmask);
434 	}
435 
436 	return 0;
437 }
438 
439 /*
440  *	RARP support.
441  */
442 
443 #ifdef IPCONFIG_RARP
444 
445 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
446 
447 static struct packet_type rarp_packet_type __initdata = {
448 	.type =	cpu_to_be16(ETH_P_RARP),
449 	.func =	ic_rarp_recv,
450 };
451 
452 static inline void __init ic_rarp_init(void)
453 {
454 	dev_add_pack(&rarp_packet_type);
455 }
456 
457 static inline void __init ic_rarp_cleanup(void)
458 {
459 	dev_remove_pack(&rarp_packet_type);
460 }
461 
462 /*
463  *  Process received RARP packet.
464  */
465 static int __init
466 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
467 {
468 	struct arphdr *rarp;
469 	unsigned char *rarp_ptr;
470 	__be32 sip, tip;
471 	unsigned char *tha;		/* t for "target" */
472 	struct ic_device *d;
473 
474 	if (!net_eq(dev_net(dev), &init_net))
475 		goto drop;
476 
477 	skb = skb_share_check(skb, GFP_ATOMIC);
478 	if (!skb)
479 		return NET_RX_DROP;
480 
481 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
482 		goto drop;
483 
484 	/* Basic sanity checks can be done without the lock.  */
485 	rarp = (struct arphdr *)skb_transport_header(skb);
486 
487 	/* If this test doesn't pass, it's not IP, or we should
488 	 * ignore it anyway.
489 	 */
490 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
491 		goto drop;
492 
493 	/* If it's not a RARP reply, delete it. */
494 	if (rarp->ar_op != htons(ARPOP_RREPLY))
495 		goto drop;
496 
497 	/* If it's not Ethernet, delete it. */
498 	if (rarp->ar_pro != htons(ETH_P_IP))
499 		goto drop;
500 
501 	if (!pskb_may_pull(skb, arp_hdr_len(dev)))
502 		goto drop;
503 
504 	/* OK, it is all there and looks valid, process... */
505 	rarp = (struct arphdr *)skb_transport_header(skb);
506 	rarp_ptr = (unsigned char *) (rarp + 1);
507 
508 	/* One reply at a time, please. */
509 	spin_lock(&ic_recv_lock);
510 
511 	/* If we already have a reply, just drop the packet */
512 	if (ic_got_reply)
513 		goto drop_unlock;
514 
515 	/* Find the ic_device that the packet arrived on */
516 	d = ic_first_dev;
517 	while (d && d->dev != dev)
518 		d = d->next;
519 	if (!d)
520 		goto drop_unlock;	/* should never happen */
521 
522 	/* Extract variable-width fields */
523 	rarp_ptr += dev->addr_len;
524 	memcpy(&sip, rarp_ptr, 4);
525 	rarp_ptr += 4;
526 	tha = rarp_ptr;
527 	rarp_ptr += dev->addr_len;
528 	memcpy(&tip, rarp_ptr, 4);
529 
530 	/* Discard packets which are not meant for us. */
531 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
532 		goto drop_unlock;
533 
534 	/* Discard packets which are not from specified server. */
535 	if (ic_servaddr != NONE && ic_servaddr != sip)
536 		goto drop_unlock;
537 
538 	/* We have a winner! */
539 	ic_dev = d;
540 	if (ic_myaddr == NONE)
541 		ic_myaddr = tip;
542 	ic_servaddr = sip;
543 	ic_addrservaddr = sip;
544 	ic_got_reply = IC_RARP;
545 
546 drop_unlock:
547 	/* Show's over.  Nothing to see here.  */
548 	spin_unlock(&ic_recv_lock);
549 
550 drop:
551 	/* Throw the packet out. */
552 	kfree_skb(skb);
553 	return 0;
554 }
555 
556 
557 /*
558  *  Send RARP request packet over a single interface.
559  */
560 static void __init ic_rarp_send_if(struct ic_device *d)
561 {
562 	struct net_device *dev = d->dev;
563 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
564 		 dev->dev_addr, dev->dev_addr);
565 }
566 #endif
567 
568 /*
569  *  Predefine Nameservers
570  */
571 static inline void __init ic_nameservers_predef(void)
572 {
573 	int i;
574 
575 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
576 		ic_nameservers[i] = NONE;
577 }
578 
579 /*
580  *	DHCP/BOOTP support.
581  */
582 
583 #ifdef IPCONFIG_BOOTP
584 
585 struct bootp_pkt {		/* BOOTP packet format */
586 	struct iphdr iph;	/* IP header */
587 	struct udphdr udph;	/* UDP header */
588 	u8 op;			/* 1=request, 2=reply */
589 	u8 htype;		/* HW address type */
590 	u8 hlen;		/* HW address length */
591 	u8 hops;		/* Used only by gateways */
592 	__be32 xid;		/* Transaction ID */
593 	__be16 secs;		/* Seconds since we started */
594 	__be16 flags;		/* Just what it says */
595 	__be32 client_ip;		/* Client's IP address if known */
596 	__be32 your_ip;		/* Assigned IP address */
597 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
598 	__be32 relay_ip;		/* IP address of BOOTP relay */
599 	u8 hw_addr[16];		/* Client's HW address */
600 	u8 serv_name[64];	/* Server host name */
601 	u8 boot_file[128];	/* Name of boot file */
602 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
603 };
604 
605 /* packet ops */
606 #define BOOTP_REQUEST	1
607 #define BOOTP_REPLY	2
608 
609 /* DHCP message types */
610 #define DHCPDISCOVER	1
611 #define DHCPOFFER	2
612 #define DHCPREQUEST	3
613 #define DHCPDECLINE	4
614 #define DHCPACK		5
615 #define DHCPNAK		6
616 #define DHCPRELEASE	7
617 #define DHCPINFORM	8
618 
619 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
620 
621 static struct packet_type bootp_packet_type __initdata = {
622 	.type =	cpu_to_be16(ETH_P_IP),
623 	.func =	ic_bootp_recv,
624 };
625 
626 /*
627  *  Initialize DHCP/BOOTP extension fields in the request.
628  */
629 
630 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
631 
632 #ifdef IPCONFIG_DHCP
633 
634 static void __init
635 ic_dhcp_init_options(u8 *options, struct ic_device *d)
636 {
637 	u8 mt = ((ic_servaddr == NONE)
638 		 ? DHCPDISCOVER : DHCPREQUEST);
639 	u8 *e = options;
640 	int len;
641 
642 	pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
643 
644 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
645 	e += 4;
646 
647 	*e++ = 53;		/* DHCP message type */
648 	*e++ = 1;
649 	*e++ = mt;
650 
651 	if (mt == DHCPREQUEST) {
652 		*e++ = 54;	/* Server ID (IP address) */
653 		*e++ = 4;
654 		memcpy(e, &ic_servaddr, 4);
655 		e += 4;
656 
657 		*e++ = 50;	/* Requested IP address */
658 		*e++ = 4;
659 		memcpy(e, &ic_myaddr, 4);
660 		e += 4;
661 	}
662 
663 	/* always? */
664 	{
665 		static const u8 ic_req_params[] = {
666 			1,	/* Subnet mask */
667 			3,	/* Default gateway */
668 			6,	/* DNS server */
669 			12,	/* Host name */
670 			15,	/* Domain name */
671 			17,	/* Boot path */
672 			26,	/* MTU */
673 			40,	/* NIS domain name */
674 		};
675 
676 		*e++ = 55;	/* Parameter request list */
677 		*e++ = sizeof(ic_req_params);
678 		memcpy(e, ic_req_params, sizeof(ic_req_params));
679 		e += sizeof(ic_req_params);
680 
681 		if (ic_host_name_set) {
682 			*e++ = 12;	/* host-name */
683 			len = strlen(utsname()->nodename);
684 			*e++ = len;
685 			memcpy(e, utsname()->nodename, len);
686 			e += len;
687 		}
688 		if (*vendor_class_identifier) {
689 			pr_info("DHCP: sending class identifier \"%s\"\n",
690 				vendor_class_identifier);
691 			*e++ = 60;	/* Class-identifier */
692 			len = strlen(vendor_class_identifier);
693 			*e++ = len;
694 			memcpy(e, vendor_class_identifier, len);
695 			e += len;
696 		}
697 		len = strlen(dhcp_client_identifier + 1);
698 		/* the minimum length of identifier is 2, include 1 byte type,
699 		 * and can not be larger than the length of options
700 		 */
701 		if (len >= 1 && len < 312 - (e - options) - 1) {
702 			*e++ = 61;
703 			*e++ = len + 1;
704 			memcpy(e, dhcp_client_identifier, len + 1);
705 			e += len + 1;
706 		}
707 	}
708 
709 	*e++ = 255;	/* End of the list */
710 }
711 
712 #endif /* IPCONFIG_DHCP */
713 
714 static void __init ic_bootp_init_ext(u8 *e)
715 {
716 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
717 	e += 4;
718 	*e++ = 1;		/* Subnet mask request */
719 	*e++ = 4;
720 	e += 4;
721 	*e++ = 3;		/* Default gateway request */
722 	*e++ = 4;
723 	e += 4;
724 	*e++ = 5;		/* Name server request */
725 	*e++ = 8;
726 	e += 8;
727 	*e++ = 12;		/* Host name request */
728 	*e++ = 32;
729 	e += 32;
730 	*e++ = 40;		/* NIS Domain name request */
731 	*e++ = 32;
732 	e += 32;
733 	*e++ = 17;		/* Boot path */
734 	*e++ = 40;
735 	e += 40;
736 
737 	*e++ = 57;		/* set extension buffer size for reply */
738 	*e++ = 2;
739 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
740 	*e++ = 150;
741 
742 	*e++ = 255;		/* End of the list */
743 }
744 
745 
746 /*
747  *  Initialize the DHCP/BOOTP mechanism.
748  */
749 static inline void __init ic_bootp_init(void)
750 {
751 	ic_nameservers_predef();
752 
753 	dev_add_pack(&bootp_packet_type);
754 }
755 
756 
757 /*
758  *  DHCP/BOOTP cleanup.
759  */
760 static inline void __init ic_bootp_cleanup(void)
761 {
762 	dev_remove_pack(&bootp_packet_type);
763 }
764 
765 
766 /*
767  *  Send DHCP/BOOTP request to single interface.
768  */
769 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
770 {
771 	struct net_device *dev = d->dev;
772 	struct sk_buff *skb;
773 	struct bootp_pkt *b;
774 	struct iphdr *h;
775 	int hlen = LL_RESERVED_SPACE(dev);
776 	int tlen = dev->needed_tailroom;
777 
778 	/* Allocate packet */
779 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
780 			GFP_KERNEL);
781 	if (!skb)
782 		return;
783 	skb_reserve(skb, hlen);
784 	b = skb_put_zero(skb, sizeof(struct bootp_pkt));
785 
786 	/* Construct IP header */
787 	skb_reset_network_header(skb);
788 	h = ip_hdr(skb);
789 	h->version = 4;
790 	h->ihl = 5;
791 	h->tot_len = htons(sizeof(struct bootp_pkt));
792 	h->frag_off = htons(IP_DF);
793 	h->ttl = 64;
794 	h->protocol = IPPROTO_UDP;
795 	h->daddr = htonl(INADDR_BROADCAST);
796 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
797 
798 	/* Construct UDP header */
799 	b->udph.source = htons(68);
800 	b->udph.dest = htons(67);
801 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
802 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
803 
804 	/* Construct DHCP/BOOTP header */
805 	b->op = BOOTP_REQUEST;
806 	if (dev->type < 256) /* check for false types */
807 		b->htype = dev->type;
808 	else if (dev->type == ARPHRD_FDDI)
809 		b->htype = ARPHRD_ETHER;
810 	else {
811 		pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
812 			dev->name);
813 		b->htype = dev->type; /* can cause undefined behavior */
814 	}
815 
816 	/* server_ip and your_ip address are both already zero per RFC2131 */
817 	b->hlen = dev->addr_len;
818 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
819 	b->secs = htons(jiffies_diff / HZ);
820 	b->xid = d->xid;
821 
822 	/* add DHCP options or BOOTP extensions */
823 #ifdef IPCONFIG_DHCP
824 	if (ic_proto_enabled & IC_USE_DHCP)
825 		ic_dhcp_init_options(b->exten, d);
826 	else
827 #endif
828 		ic_bootp_init_ext(b->exten);
829 
830 	/* Chain packet down the line... */
831 	skb->dev = dev;
832 	skb->protocol = htons(ETH_P_IP);
833 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
834 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
835 		kfree_skb(skb);
836 		printk("E");
837 		return;
838 	}
839 
840 	if (dev_queue_xmit(skb) < 0)
841 		printk("E");
842 }
843 
844 
845 /*
846  *  Copy BOOTP-supplied string if not already set.
847  */
848 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
849 {
850 	if (!len)
851 		return 0;
852 	if (len > max-1)
853 		len = max-1;
854 	memcpy(dest, src, len);
855 	dest[len] = '\0';
856 	return 1;
857 }
858 
859 
860 /*
861  *  Process BOOTP extensions.
862  */
863 static void __init ic_do_bootp_ext(u8 *ext)
864 {
865 	u8 servers;
866 	int i;
867 	__be16 mtu;
868 
869 	u8 *c;
870 
871 	pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
872 	for (c=ext+2; c<ext+2+ext[1]; c++)
873 		pr_debug(" %02x", *c);
874 	pr_debug("\n");
875 
876 	switch (*ext++) {
877 	case 1:		/* Subnet mask */
878 		if (ic_netmask == NONE)
879 			memcpy(&ic_netmask, ext+1, 4);
880 		break;
881 	case 3:		/* Default gateway */
882 		if (ic_gateway == NONE)
883 			memcpy(&ic_gateway, ext+1, 4);
884 		break;
885 	case 6:		/* DNS server */
886 		servers= *ext/4;
887 		if (servers > CONF_NAMESERVERS_MAX)
888 			servers = CONF_NAMESERVERS_MAX;
889 		for (i = 0; i < servers; i++) {
890 			if (ic_nameservers[i] == NONE)
891 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
892 		}
893 		break;
894 	case 12:	/* Host name */
895 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
896 				__NEW_UTS_LEN);
897 		ic_host_name_set = 1;
898 		break;
899 	case 15:	/* Domain name (DNS) */
900 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
901 		break;
902 	case 17:	/* Root path */
903 		if (!root_server_path[0])
904 			ic_bootp_string(root_server_path, ext+1, *ext,
905 					sizeof(root_server_path));
906 		break;
907 	case 26:	/* Interface MTU */
908 		memcpy(&mtu, ext+1, sizeof(mtu));
909 		ic_dev_mtu = ntohs(mtu);
910 		break;
911 	case 40:	/* NIS Domain name (_not_ DNS) */
912 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
913 				__NEW_UTS_LEN);
914 		break;
915 	}
916 }
917 
918 
919 /*
920  *  Receive BOOTP reply.
921  */
922 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
923 {
924 	struct bootp_pkt *b;
925 	struct iphdr *h;
926 	struct ic_device *d;
927 	int len, ext_len;
928 
929 	if (!net_eq(dev_net(dev), &init_net))
930 		goto drop;
931 
932 	/* Perform verifications before taking the lock.  */
933 	if (skb->pkt_type == PACKET_OTHERHOST)
934 		goto drop;
935 
936 	skb = skb_share_check(skb, GFP_ATOMIC);
937 	if (!skb)
938 		return NET_RX_DROP;
939 
940 	if (!pskb_may_pull(skb,
941 			   sizeof(struct iphdr) +
942 			   sizeof(struct udphdr)))
943 		goto drop;
944 
945 	b = (struct bootp_pkt *)skb_network_header(skb);
946 	h = &b->iph;
947 
948 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
949 		goto drop;
950 
951 	/* Fragments are not supported */
952 	if (ip_is_fragment(h)) {
953 		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
954 		goto drop;
955 	}
956 
957 	if (skb->len < ntohs(h->tot_len))
958 		goto drop;
959 
960 	if (ip_fast_csum((char *) h, h->ihl))
961 		goto drop;
962 
963 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
964 		goto drop;
965 
966 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
967 		goto drop;
968 
969 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
970 	ext_len = len - (sizeof(*b) -
971 			 sizeof(struct iphdr) -
972 			 sizeof(struct udphdr) -
973 			 sizeof(b->exten));
974 	if (ext_len < 0)
975 		goto drop;
976 
977 	/* Ok the front looks good, make sure we can get at the rest.  */
978 	if (!pskb_may_pull(skb, skb->len))
979 		goto drop;
980 
981 	b = (struct bootp_pkt *)skb_network_header(skb);
982 	h = &b->iph;
983 
984 	/* One reply at a time, please. */
985 	spin_lock(&ic_recv_lock);
986 
987 	/* If we already have a reply, just drop the packet */
988 	if (ic_got_reply)
989 		goto drop_unlock;
990 
991 	/* Find the ic_device that the packet arrived on */
992 	d = ic_first_dev;
993 	while (d && d->dev != dev)
994 		d = d->next;
995 	if (!d)
996 		goto drop_unlock;  /* should never happen */
997 
998 	/* Is it a reply to our BOOTP request? */
999 	if (b->op != BOOTP_REPLY ||
1000 	    b->xid != d->xid) {
1001 		net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1002 				    d->dev->name, b->op, b->xid);
1003 		goto drop_unlock;
1004 	}
1005 
1006 	/* Parse extensions */
1007 	if (ext_len >= 4 &&
1008 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1009 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1010 		u8 *ext;
1011 
1012 #ifdef IPCONFIG_DHCP
1013 		if (ic_proto_enabled & IC_USE_DHCP) {
1014 			__be32 server_id = NONE;
1015 			int mt = 0;
1016 
1017 			ext = &b->exten[4];
1018 			while (ext < end && *ext != 0xff) {
1019 				u8 *opt = ext++;
1020 				if (*opt == 0)	/* Padding */
1021 					continue;
1022 				ext += *ext + 1;
1023 				if (ext >= end)
1024 					break;
1025 				switch (*opt) {
1026 				case 53:	/* Message type */
1027 					if (opt[1])
1028 						mt = opt[2];
1029 					break;
1030 				case 54:	/* Server ID (IP address) */
1031 					if (opt[1] >= 4)
1032 						memcpy(&server_id, opt + 2, 4);
1033 					break;
1034 				}
1035 			}
1036 
1037 			pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
1038 
1039 			switch (mt) {
1040 			case DHCPOFFER:
1041 				/* While in the process of accepting one offer,
1042 				 * ignore all others.
1043 				 */
1044 				if (ic_myaddr != NONE)
1045 					goto drop_unlock;
1046 
1047 				/* Let's accept that offer. */
1048 				ic_myaddr = b->your_ip;
1049 				ic_servaddr = server_id;
1050 				pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1051 					 &ic_myaddr, &b->iph.saddr);
1052 				/* The DHCP indicated server address takes
1053 				 * precedence over the bootp header one if
1054 				 * they are different.
1055 				 */
1056 				if ((server_id != NONE) &&
1057 				    (b->server_ip != server_id))
1058 					b->server_ip = ic_servaddr;
1059 				break;
1060 
1061 			case DHCPACK:
1062 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1063 					goto drop_unlock;
1064 
1065 				/* Yeah! */
1066 				break;
1067 
1068 			default:
1069 				/* Urque.  Forget it*/
1070 				ic_myaddr = NONE;
1071 				ic_servaddr = NONE;
1072 				goto drop_unlock;
1073 			}
1074 
1075 			ic_dhcp_msgtype = mt;
1076 
1077 		}
1078 #endif /* IPCONFIG_DHCP */
1079 
1080 		ext = &b->exten[4];
1081 		while (ext < end && *ext != 0xff) {
1082 			u8 *opt = ext++;
1083 			if (*opt == 0)	/* Padding */
1084 				continue;
1085 			ext += *ext + 1;
1086 			if (ext < end)
1087 				ic_do_bootp_ext(opt);
1088 		}
1089 	}
1090 
1091 	/* We have a winner! */
1092 	ic_dev = d;
1093 	ic_myaddr = b->your_ip;
1094 	ic_servaddr = b->server_ip;
1095 	ic_addrservaddr = b->iph.saddr;
1096 	if (ic_gateway == NONE && b->relay_ip)
1097 		ic_gateway = b->relay_ip;
1098 	if (ic_nameservers[0] == NONE)
1099 		ic_nameservers[0] = ic_servaddr;
1100 	ic_got_reply = IC_BOOTP;
1101 
1102 drop_unlock:
1103 	/* Show's over.  Nothing to see here.  */
1104 	spin_unlock(&ic_recv_lock);
1105 
1106 drop:
1107 	/* Throw the packet out. */
1108 	kfree_skb(skb);
1109 
1110 	return 0;
1111 }
1112 
1113 
1114 #endif
1115 
1116 
1117 /*
1118  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1119  */
1120 
1121 #ifdef IPCONFIG_DYNAMIC
1122 
1123 static int __init ic_dynamic(void)
1124 {
1125 	int retries;
1126 	struct ic_device *d;
1127 	unsigned long start_jiffies, timeout, jiff;
1128 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1129 	int do_rarp = ic_proto_have_if & IC_RARP;
1130 
1131 	/*
1132 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1133 	 * This routine gets only called when some pieces of information
1134 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1135 	 */
1136 	if (!ic_proto_enabled) {
1137 		pr_err("IP-Config: Incomplete network configuration information\n");
1138 		return -1;
1139 	}
1140 
1141 #ifdef IPCONFIG_BOOTP
1142 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1143 		pr_err("DHCP/BOOTP: No suitable device found\n");
1144 #endif
1145 #ifdef IPCONFIG_RARP
1146 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1147 		pr_err("RARP: No suitable device found\n");
1148 #endif
1149 
1150 	if (!ic_proto_have_if)
1151 		/* Error message already printed */
1152 		return -1;
1153 
1154 	/*
1155 	 * Setup protocols
1156 	 */
1157 #ifdef IPCONFIG_BOOTP
1158 	if (do_bootp)
1159 		ic_bootp_init();
1160 #endif
1161 #ifdef IPCONFIG_RARP
1162 	if (do_rarp)
1163 		ic_rarp_init();
1164 #endif
1165 
1166 	/*
1167 	 * Send requests and wait, until we get an answer. This loop
1168 	 * seems to be a terrible waste of CPU time, but actually there is
1169 	 * only one process running at all, so we don't need to use any
1170 	 * scheduler functions.
1171 	 * [Actually we could now, but the nothing else running note still
1172 	 *  applies.. - AC]
1173 	 */
1174 	pr_notice("Sending %s%s%s requests .",
1175 		  do_bootp
1176 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1177 		  (do_bootp && do_rarp) ? " and " : "",
1178 		  do_rarp ? "RARP" : "");
1179 
1180 	start_jiffies = jiffies;
1181 	d = ic_first_dev;
1182 	retries = CONF_SEND_RETRIES;
1183 	get_random_bytes(&timeout, sizeof(timeout));
1184 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1185 	for (;;) {
1186 #ifdef IPCONFIG_BOOTP
1187 		if (do_bootp && (d->able & IC_BOOTP))
1188 			ic_bootp_send_if(d, jiffies - start_jiffies);
1189 #endif
1190 #ifdef IPCONFIG_RARP
1191 		if (do_rarp && (d->able & IC_RARP))
1192 			ic_rarp_send_if(d);
1193 #endif
1194 
1195 		if (!d->next) {
1196 			jiff = jiffies + timeout;
1197 			while (time_before(jiffies, jiff) && !ic_got_reply)
1198 				schedule_timeout_uninterruptible(1);
1199 		}
1200 #ifdef IPCONFIG_DHCP
1201 		/* DHCP isn't done until we get a DHCPACK. */
1202 		if ((ic_got_reply & IC_BOOTP) &&
1203 		    (ic_proto_enabled & IC_USE_DHCP) &&
1204 		    ic_dhcp_msgtype != DHCPACK) {
1205 			ic_got_reply = 0;
1206 			/* continue on device that got the reply */
1207 			d = ic_dev;
1208 			pr_cont(",");
1209 			continue;
1210 		}
1211 #endif /* IPCONFIG_DHCP */
1212 
1213 		if (ic_got_reply) {
1214 			pr_cont(" OK\n");
1215 			break;
1216 		}
1217 
1218 		if ((d = d->next))
1219 			continue;
1220 
1221 		if (! --retries) {
1222 			pr_cont(" timed out!\n");
1223 			break;
1224 		}
1225 
1226 		d = ic_first_dev;
1227 
1228 		timeout = timeout CONF_TIMEOUT_MULT;
1229 		if (timeout > CONF_TIMEOUT_MAX)
1230 			timeout = CONF_TIMEOUT_MAX;
1231 
1232 		pr_cont(".");
1233 	}
1234 
1235 #ifdef IPCONFIG_BOOTP
1236 	if (do_bootp)
1237 		ic_bootp_cleanup();
1238 #endif
1239 #ifdef IPCONFIG_RARP
1240 	if (do_rarp)
1241 		ic_rarp_cleanup();
1242 #endif
1243 
1244 	if (!ic_got_reply) {
1245 		ic_myaddr = NONE;
1246 		return -1;
1247 	}
1248 
1249 	pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1250 		((ic_got_reply & IC_RARP) ? "RARP"
1251 		: (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1252 		&ic_addrservaddr, &ic_myaddr);
1253 
1254 	return 0;
1255 }
1256 
1257 #endif /* IPCONFIG_DYNAMIC */
1258 
1259 #ifdef CONFIG_PROC_FS
1260 
1261 static int pnp_seq_show(struct seq_file *seq, void *v)
1262 {
1263 	int i;
1264 
1265 	if (ic_proto_used & IC_PROTO)
1266 		seq_printf(seq, "#PROTO: %s\n",
1267 			   (ic_proto_used & IC_RARP) ? "RARP"
1268 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1269 	else
1270 		seq_puts(seq, "#MANUAL\n");
1271 
1272 	if (ic_domain[0])
1273 		seq_printf(seq,
1274 			   "domain %s\n", ic_domain);
1275 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1276 		if (ic_nameservers[i] != NONE)
1277 			seq_printf(seq, "nameserver %pI4\n",
1278 				   &ic_nameservers[i]);
1279 	}
1280 	if (ic_servaddr != NONE)
1281 		seq_printf(seq, "bootserver %pI4\n",
1282 			   &ic_servaddr);
1283 	return 0;
1284 }
1285 
1286 static int pnp_seq_open(struct inode *indoe, struct file *file)
1287 {
1288 	return single_open(file, pnp_seq_show, NULL);
1289 }
1290 
1291 static const struct file_operations pnp_seq_fops = {
1292 	.open		= pnp_seq_open,
1293 	.read		= seq_read,
1294 	.llseek		= seq_lseek,
1295 	.release	= single_release,
1296 };
1297 #endif /* CONFIG_PROC_FS */
1298 
1299 /*
1300  *  Extract IP address from the parameter string if needed. Note that we
1301  *  need to have root_server_addr set _before_ IPConfig gets called as it
1302  *  can override it.
1303  */
1304 __be32 __init root_nfs_parse_addr(char *name)
1305 {
1306 	__be32 addr;
1307 	int octets = 0;
1308 	char *cp, *cq;
1309 
1310 	cp = cq = name;
1311 	while (octets < 4) {
1312 		while (*cp >= '0' && *cp <= '9')
1313 			cp++;
1314 		if (cp == cq || cp - cq > 3)
1315 			break;
1316 		if (*cp == '.' || octets == 3)
1317 			octets++;
1318 		if (octets < 4)
1319 			cp++;
1320 		cq = cp;
1321 	}
1322 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1323 		if (*cp == ':')
1324 			*cp++ = '\0';
1325 		addr = in_aton(name);
1326 		memmove(name, cp, strlen(cp) + 1);
1327 	} else
1328 		addr = NONE;
1329 
1330 	return addr;
1331 }
1332 
1333 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1334 
1335 static int __init wait_for_devices(void)
1336 {
1337 	int i;
1338 
1339 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1340 		struct net_device *dev;
1341 		int found = 0;
1342 
1343 		rtnl_lock();
1344 		for_each_netdev(&init_net, dev) {
1345 			if (ic_is_init_dev(dev)) {
1346 				found = 1;
1347 				break;
1348 			}
1349 		}
1350 		rtnl_unlock();
1351 		if (found)
1352 			return 0;
1353 		ssleep(1);
1354 	}
1355 	return -ENODEV;
1356 }
1357 
1358 /*
1359  *	IP Autoconfig dispatcher.
1360  */
1361 
1362 static int __init ip_auto_config(void)
1363 {
1364 	__be32 addr;
1365 #ifdef IPCONFIG_DYNAMIC
1366 	int retries = CONF_OPEN_RETRIES;
1367 #endif
1368 	int err;
1369 	unsigned int i;
1370 
1371 #ifdef CONFIG_PROC_FS
1372 	proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1373 #endif /* CONFIG_PROC_FS */
1374 
1375 	if (!ic_enable)
1376 		return 0;
1377 
1378 	pr_debug("IP-Config: Entered.\n");
1379 #ifdef IPCONFIG_DYNAMIC
1380  try_try_again:
1381 #endif
1382 	/* Wait for devices to appear */
1383 	err = wait_for_devices();
1384 	if (err)
1385 		return err;
1386 
1387 	/* Setup all network devices */
1388 	err = ic_open_devs();
1389 	if (err)
1390 		return err;
1391 
1392 	/* Give drivers a chance to settle */
1393 	msleep(CONF_POST_OPEN);
1394 
1395 	/*
1396 	 * If the config information is insufficient (e.g., our IP address or
1397 	 * IP address of the boot server is missing or we have multiple network
1398 	 * interfaces and no default was set), use BOOTP or RARP to get the
1399 	 * missing values.
1400 	 */
1401 	if (ic_myaddr == NONE ||
1402 #ifdef CONFIG_ROOT_NFS
1403 	    (root_server_addr == NONE &&
1404 	     ic_servaddr == NONE &&
1405 	     ROOT_DEV == Root_NFS) ||
1406 #endif
1407 	    ic_first_dev->next) {
1408 #ifdef IPCONFIG_DYNAMIC
1409 		if (ic_dynamic() < 0) {
1410 			ic_close_devs();
1411 
1412 			/*
1413 			 * I don't know why, but sometimes the
1414 			 * eepro100 driver (at least) gets upset and
1415 			 * doesn't work the first time it's opened.
1416 			 * But then if you close it and reopen it, it
1417 			 * works just fine.  So we need to try that at
1418 			 * least once before giving up.
1419 			 *
1420 			 * Also, if the root will be NFS-mounted, we
1421 			 * have nowhere to go if DHCP fails.  So we
1422 			 * just have to keep trying forever.
1423 			 *
1424 			 * 				-- Chip
1425 			 */
1426 #ifdef CONFIG_ROOT_NFS
1427 			if (ROOT_DEV ==  Root_NFS) {
1428 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1429 				goto try_try_again;
1430 			}
1431 #endif
1432 
1433 			if (--retries) {
1434 				pr_err("IP-Config: Reopening network devices...\n");
1435 				goto try_try_again;
1436 			}
1437 
1438 			/* Oh, well.  At least we tried. */
1439 			pr_err("IP-Config: Auto-configuration of network failed\n");
1440 			return -1;
1441 		}
1442 #else /* !DYNAMIC */
1443 		pr_err("IP-Config: Incomplete network configuration information\n");
1444 		ic_close_devs();
1445 		return -1;
1446 #endif /* IPCONFIG_DYNAMIC */
1447 	} else {
1448 		/* Device selected manually or only one device -> use it */
1449 		ic_dev = ic_first_dev;
1450 	}
1451 
1452 	addr = root_nfs_parse_addr(root_server_path);
1453 	if (root_server_addr == NONE)
1454 		root_server_addr = addr;
1455 
1456 	/*
1457 	 * Use defaults wherever applicable.
1458 	 */
1459 	if (ic_defaults() < 0)
1460 		return -1;
1461 
1462 	/*
1463 	 * Record which protocol was actually used.
1464 	 */
1465 #ifdef IPCONFIG_DYNAMIC
1466 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1467 #endif
1468 
1469 #ifndef IPCONFIG_SILENT
1470 	/*
1471 	 * Clue in the operator.
1472 	 */
1473 	pr_info("IP-Config: Complete:\n");
1474 
1475 	pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1476 		ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1477 		&ic_myaddr, &ic_netmask, &ic_gateway);
1478 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1479 		utsname()->nodename, ic_domain, utsname()->domainname);
1480 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1481 		&ic_servaddr, &root_server_addr, root_server_path);
1482 	if (ic_dev_mtu)
1483 		pr_cont(", mtu=%d", ic_dev_mtu);
1484 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1485 		if (ic_nameservers[i] != NONE) {
1486 			pr_cont("     nameserver%u=%pI4",
1487 				i, &ic_nameservers[i]);
1488 			break;
1489 		}
1490 	for (i++; i < CONF_NAMESERVERS_MAX; i++)
1491 		if (ic_nameservers[i] != NONE)
1492 			pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1493 	pr_cont("\n");
1494 #endif /* !SILENT */
1495 
1496 	/*
1497 	 * Close all network devices except the device we've
1498 	 * autoconfigured and set up routes.
1499 	 */
1500 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1501 		err = -1;
1502 	else
1503 		err = 0;
1504 
1505 	ic_close_devs();
1506 
1507 	return err;
1508 }
1509 
1510 late_initcall(ip_auto_config);
1511 
1512 
1513 /*
1514  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1515  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1516  */
1517 static int __init ic_proto_name(char *name)
1518 {
1519 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1520 		return 1;
1521 	}
1522 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1523 		return 0;
1524 	}
1525 #ifdef CONFIG_IP_PNP_DHCP
1526 	else if (!strncmp(name, "dhcp", 4)) {
1527 		char *client_id;
1528 
1529 		ic_proto_enabled &= ~IC_RARP;
1530 		client_id = strstr(name, "dhcp,");
1531 		if (client_id) {
1532 			char *v;
1533 
1534 			client_id = client_id + 5;
1535 			v = strchr(client_id, ',');
1536 			if (!v)
1537 				return 1;
1538 			*v = 0;
1539 			if (kstrtou8(client_id, 0, dhcp_client_identifier))
1540 				pr_debug("DHCP: Invalid client identifier type\n");
1541 			strncpy(dhcp_client_identifier + 1, v + 1, 251);
1542 			*v = ',';
1543 		}
1544 		return 1;
1545 	}
1546 #endif
1547 #ifdef CONFIG_IP_PNP_BOOTP
1548 	else if (!strcmp(name, "bootp")) {
1549 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1550 		return 1;
1551 	}
1552 #endif
1553 #ifdef CONFIG_IP_PNP_RARP
1554 	else if (!strcmp(name, "rarp")) {
1555 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1556 		return 1;
1557 	}
1558 #endif
1559 #ifdef IPCONFIG_DYNAMIC
1560 	else if (!strcmp(name, "both")) {
1561 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1562 		return 1;
1563 	}
1564 #endif
1565 	return 0;
1566 }
1567 
1568 static int __init ip_auto_config_setup(char *addrs)
1569 {
1570 	char *cp, *ip, *dp;
1571 	int num = 0;
1572 
1573 	ic_set_manually = 1;
1574 	ic_enable = 1;
1575 
1576 	/*
1577 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1578 	 * and skip the below static IP processing.
1579 	 */
1580 	if (ic_proto_name(addrs))
1581 		return 1;
1582 
1583 	/* If no static IP is given, turn off autoconfig and bail.  */
1584 	if (*addrs == 0 ||
1585 	    strcmp(addrs, "off") == 0 ||
1586 	    strcmp(addrs, "none") == 0) {
1587 		ic_enable = 0;
1588 		return 1;
1589 	}
1590 
1591 	ic_nameservers_predef();
1592 
1593 	/* Parse string for static IP assignment.  */
1594 	ip = addrs;
1595 	while (ip && *ip) {
1596 		if ((cp = strchr(ip, ':')))
1597 			*cp++ = '\0';
1598 		if (strlen(ip) > 0) {
1599 			pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1600 			switch (num) {
1601 			case 0:
1602 				if ((ic_myaddr = in_aton(ip)) == ANY)
1603 					ic_myaddr = NONE;
1604 				break;
1605 			case 1:
1606 				if ((ic_servaddr = in_aton(ip)) == ANY)
1607 					ic_servaddr = NONE;
1608 				break;
1609 			case 2:
1610 				if ((ic_gateway = in_aton(ip)) == ANY)
1611 					ic_gateway = NONE;
1612 				break;
1613 			case 3:
1614 				if ((ic_netmask = in_aton(ip)) == ANY)
1615 					ic_netmask = NONE;
1616 				break;
1617 			case 4:
1618 				if ((dp = strchr(ip, '.'))) {
1619 					*dp++ = '\0';
1620 					strlcpy(utsname()->domainname, dp,
1621 						sizeof(utsname()->domainname));
1622 				}
1623 				strlcpy(utsname()->nodename, ip,
1624 					sizeof(utsname()->nodename));
1625 				ic_host_name_set = 1;
1626 				break;
1627 			case 5:
1628 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1629 				break;
1630 			case 6:
1631 				if (ic_proto_name(ip) == 0 &&
1632 				    ic_myaddr == NONE) {
1633 					ic_enable = 0;
1634 				}
1635 				break;
1636 			case 7:
1637 				if (CONF_NAMESERVERS_MAX >= 1) {
1638 					ic_nameservers[0] = in_aton(ip);
1639 					if (ic_nameservers[0] == ANY)
1640 						ic_nameservers[0] = NONE;
1641 				}
1642 				break;
1643 			case 8:
1644 				if (CONF_NAMESERVERS_MAX >= 2) {
1645 					ic_nameservers[1] = in_aton(ip);
1646 					if (ic_nameservers[1] == ANY)
1647 						ic_nameservers[1] = NONE;
1648 				}
1649 				break;
1650 			}
1651 		}
1652 		ip = cp;
1653 		num++;
1654 	}
1655 
1656 	return 1;
1657 }
1658 __setup("ip=", ip_auto_config_setup);
1659 
1660 static int __init nfsaddrs_config_setup(char *addrs)
1661 {
1662 	return ip_auto_config_setup(addrs);
1663 }
1664 __setup("nfsaddrs=", nfsaddrs_config_setup);
1665 
1666 static int __init vendor_class_identifier_setup(char *addrs)
1667 {
1668 	if (strlcpy(vendor_class_identifier, addrs,
1669 		    sizeof(vendor_class_identifier))
1670 	    >= sizeof(vendor_class_identifier))
1671 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1672 			vendor_class_identifier);
1673 	return 1;
1674 }
1675 __setup("dhcpclass=", vendor_class_identifier_setup);
1676