xref: /openbmc/linux/net/ipv4/ipconfig.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  *  $Id: ipconfig.c,v 1.46 2002/02/01 22:01:04 davem Exp $
3  *
4  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
5  *  user-supplied information to configure own IP address and routes.
6  *
7  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
8  *
9  *  Derived from network configuration code in fs/nfs/nfsroot.c,
10  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
11  *
12  *  BOOTP rewritten to construct and analyse packets itself instead
13  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
14  *					     -- MJ, December 1998
15  *
16  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
17  *  initialization scheme.
18  *	- Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
19  *
20  *  DHCP support added.  To users this looks like a whole separate
21  *  protocol, but we know it's just a bag on the side of BOOTP.
22  *		-- Chip Salzenberg <chip@valinux.com>, May 2000
23  *
24  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
25  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
26  *
27  *  Merged changes from 2.2.19 into 2.4.3
28  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
29  *
30  *  Multiple Nameservers in /proc/net/pnp
31  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
32  */
33 
34 #include <linux/types.h>
35 #include <linux/string.h>
36 #include <linux/kernel.h>
37 #include <linux/jiffies.h>
38 #include <linux/random.h>
39 #include <linux/init.h>
40 #include <linux/utsname.h>
41 #include <linux/in.h>
42 #include <linux/if.h>
43 #include <linux/inet.h>
44 #include <linux/inetdevice.h>
45 #include <linux/netdevice.h>
46 #include <linux/if_arp.h>
47 #include <linux/skbuff.h>
48 #include <linux/ip.h>
49 #include <linux/socket.h>
50 #include <linux/route.h>
51 #include <linux/udp.h>
52 #include <linux/proc_fs.h>
53 #include <linux/seq_file.h>
54 #include <linux/major.h>
55 #include <linux/root_dev.h>
56 #include <linux/delay.h>
57 #include <linux/nfs_fs.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 /* Define this to allow debugging output */
69 #undef IPCONFIG_DEBUG
70 
71 #ifdef IPCONFIG_DEBUG
72 #define DBG(x) printk x
73 #else
74 #define DBG(x) do { } while(0)
75 #endif
76 
77 #if defined(CONFIG_IP_PNP_DHCP)
78 #define IPCONFIG_DHCP
79 #endif
80 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
81 #define IPCONFIG_BOOTP
82 #endif
83 #if defined(CONFIG_IP_PNP_RARP)
84 #define IPCONFIG_RARP
85 #endif
86 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
87 #define IPCONFIG_DYNAMIC
88 #endif
89 
90 /* Define the friendly delay before and after opening net devices */
91 #define CONF_PRE_OPEN		500	/* Before opening: 1/2 second */
92 #define CONF_POST_OPEN		1	/* After opening: 1 second */
93 
94 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
95 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
96 #define CONF_SEND_RETRIES 	6	/* Send six requests per open */
97 #define CONF_INTER_TIMEOUT	(HZ/2)	/* Inter-device timeout: 1/2 second */
98 #define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
99 #define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
100 #define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
101 #define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
102 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
103 					   - '3' from resolv.h */
104 
105 #define NONE __constant_htonl(INADDR_NONE)
106 
107 /*
108  * Public IP configuration
109  */
110 
111 /* This is used by platforms which might be able to set the ipconfig
112  * variables using firmware environment vars.  If this is set, it will
113  * ignore such firmware variables.
114  */
115 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
116 
117 static int ic_enable __initdata = 0;		/* IP config enabled? */
118 
119 /* Protocol choice */
120 int ic_proto_enabled __initdata = 0
121 #ifdef IPCONFIG_BOOTP
122 			| IC_BOOTP
123 #endif
124 #ifdef CONFIG_IP_PNP_DHCP
125 			| IC_USE_DHCP
126 #endif
127 #ifdef IPCONFIG_RARP
128 			| IC_RARP
129 #endif
130 			;
131 
132 static int ic_host_name_set __initdata = 0;	/* Host name set by us? */
133 
134 __be32 ic_myaddr = NONE;		/* My IP address */
135 static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
136 __be32 ic_gateway = NONE;	/* Gateway IP address */
137 
138 __be32 ic_servaddr = NONE;	/* Boot server IP address */
139 
140 __be32 root_server_addr = NONE;	/* Address of NFS server */
141 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
142 
143 /* Persistent data: */
144 
145 static int ic_proto_used;			/* Protocol used, if any */
146 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
147 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
148 
149 /*
150  * Private state.
151  */
152 
153 /* Name of user-selected boot device */
154 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
155 
156 /* Protocols supported by available interfaces */
157 static int ic_proto_have_if __initdata = 0;
158 
159 #ifdef IPCONFIG_DYNAMIC
160 static DEFINE_SPINLOCK(ic_recv_lock);
161 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
162 #endif
163 #ifdef IPCONFIG_DHCP
164 static int ic_dhcp_msgtype __initdata = 0;	/* DHCP msg type received */
165 #endif
166 
167 
168 /*
169  *	Network devices
170  */
171 
172 struct ic_device {
173 	struct ic_device *next;
174 	struct net_device *dev;
175 	unsigned short flags;
176 	short able;
177 	__be32 xid;
178 };
179 
180 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
181 static struct net_device *ic_dev __initdata = NULL;	/* Selected device */
182 
183 static int __init ic_open_devs(void)
184 {
185 	struct ic_device *d, **last;
186 	struct net_device *dev;
187 	unsigned short oflags;
188 
189 	last = &ic_first_dev;
190 	rtnl_lock();
191 
192 	/* bring loopback device up first */
193 	for_each_netdev(&init_net, dev) {
194 		if (!(dev->flags & IFF_LOOPBACK))
195 			continue;
196 		if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
197 			printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
198 	}
199 
200 	for_each_netdev(&init_net, dev) {
201 		if (dev->flags & IFF_LOOPBACK)
202 			continue;
203 		if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
204 		    (!(dev->flags & IFF_LOOPBACK) &&
205 		     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
206 		     strncmp(dev->name, "dummy", 5))) {
207 			int able = 0;
208 			if (dev->mtu >= 364)
209 				able |= IC_BOOTP;
210 			else
211 				printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
212 			if (!(dev->flags & IFF_NOARP))
213 				able |= IC_RARP;
214 			able &= ic_proto_enabled;
215 			if (ic_proto_enabled && !able)
216 				continue;
217 			oflags = dev->flags;
218 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
219 				printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
220 				continue;
221 			}
222 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
223 				rtnl_unlock();
224 				return -1;
225 			}
226 			d->dev = dev;
227 			*last = d;
228 			last = &d->next;
229 			d->flags = oflags;
230 			d->able = able;
231 			if (able & IC_BOOTP)
232 				get_random_bytes(&d->xid, sizeof(__be32));
233 			else
234 				d->xid = 0;
235 			ic_proto_have_if |= able;
236 			DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
237 				dev->name, able, d->xid));
238 		}
239 	}
240 	rtnl_unlock();
241 
242 	*last = NULL;
243 
244 	if (!ic_first_dev) {
245 		if (user_dev_name[0])
246 			printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
247 		else
248 			printk(KERN_ERR "IP-Config: No network devices available.\n");
249 		return -1;
250 	}
251 	return 0;
252 }
253 
254 static void __init ic_close_devs(void)
255 {
256 	struct ic_device *d, *next;
257 	struct net_device *dev;
258 
259 	rtnl_lock();
260 	next = ic_first_dev;
261 	while ((d = next)) {
262 		next = d->next;
263 		dev = d->dev;
264 		if (dev != ic_dev) {
265 			DBG(("IP-Config: Downing %s\n", dev->name));
266 			dev_change_flags(dev, d->flags);
267 		}
268 		kfree(d);
269 	}
270 	rtnl_unlock();
271 }
272 
273 /*
274  *	Interface to various network functions.
275  */
276 
277 static inline void
278 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
279 {
280 	sin->sin_family = AF_INET;
281 	sin->sin_addr.s_addr = addr;
282 	sin->sin_port = port;
283 }
284 
285 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
286 {
287 	int res;
288 
289 	mm_segment_t oldfs = get_fs();
290 	set_fs(get_ds());
291 	res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
292 	set_fs(oldfs);
293 	return res;
294 }
295 
296 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
297 {
298 	int res;
299 
300 	mm_segment_t oldfs = get_fs();
301 	set_fs(get_ds());
302 	res = ip_rt_ioctl(cmd, (void __user *) arg);
303 	set_fs(oldfs);
304 	return res;
305 }
306 
307 /*
308  *	Set up interface addresses and routes.
309  */
310 
311 static int __init ic_setup_if(void)
312 {
313 	struct ifreq ir;
314 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
315 	int err;
316 
317 	memset(&ir, 0, sizeof(ir));
318 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
319 	set_sockaddr(sin, ic_myaddr, 0);
320 	if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
321 		printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
322 		return -1;
323 	}
324 	set_sockaddr(sin, ic_netmask, 0);
325 	if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
326 		printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
327 		return -1;
328 	}
329 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
330 	if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
331 		printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
332 		return -1;
333 	}
334 	return 0;
335 }
336 
337 static int __init ic_setup_routes(void)
338 {
339 	/* No need to setup device routes, only the default route... */
340 
341 	if (ic_gateway != NONE) {
342 		struct rtentry rm;
343 		int err;
344 
345 		memset(&rm, 0, sizeof(rm));
346 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
347 			printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
348 			return -1;
349 		}
350 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
351 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
352 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
353 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
354 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
355 			printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
356 			return -1;
357 		}
358 	}
359 
360 	return 0;
361 }
362 
363 /*
364  *	Fill in default values for all missing parameters.
365  */
366 
367 static int __init ic_defaults(void)
368 {
369 	/*
370 	 *	At this point we have no userspace running so need not
371 	 *	claim locks on system_utsname
372 	 */
373 
374 	if (!ic_host_name_set)
375 		sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
376 
377 	if (root_server_addr == NONE)
378 		root_server_addr = ic_servaddr;
379 
380 	if (ic_netmask == NONE) {
381 		if (IN_CLASSA(ntohl(ic_myaddr)))
382 			ic_netmask = htonl(IN_CLASSA_NET);
383 		else if (IN_CLASSB(ntohl(ic_myaddr)))
384 			ic_netmask = htonl(IN_CLASSB_NET);
385 		else if (IN_CLASSC(ntohl(ic_myaddr)))
386 			ic_netmask = htonl(IN_CLASSC_NET);
387 		else {
388 			printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
389 				NIPQUAD(ic_myaddr));
390 			return -1;
391 		}
392 		printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
393 	}
394 
395 	return 0;
396 }
397 
398 /*
399  *	RARP support.
400  */
401 
402 #ifdef IPCONFIG_RARP
403 
404 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
405 
406 static struct packet_type rarp_packet_type __initdata = {
407 	.type =	__constant_htons(ETH_P_RARP),
408 	.func =	ic_rarp_recv,
409 };
410 
411 static inline void ic_rarp_init(void)
412 {
413 	dev_add_pack(&rarp_packet_type);
414 }
415 
416 static inline void ic_rarp_cleanup(void)
417 {
418 	dev_remove_pack(&rarp_packet_type);
419 }
420 
421 /*
422  *  Process received RARP packet.
423  */
424 static int __init
425 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
426 {
427 	struct arphdr *rarp;
428 	unsigned char *rarp_ptr;
429 	__be32 sip, tip;
430 	unsigned char *sha, *tha;		/* s for "source", t for "target" */
431 	struct ic_device *d;
432 
433 	if (dev->nd_net != &init_net)
434 		goto drop;
435 
436 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
437 		return NET_RX_DROP;
438 
439 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
440 		goto drop;
441 
442 	/* Basic sanity checks can be done without the lock.  */
443 	rarp = (struct arphdr *)skb_transport_header(skb);
444 
445 	/* If this test doesn't pass, it's not IP, or we should
446 	 * ignore it anyway.
447 	 */
448 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
449 		goto drop;
450 
451 	/* If it's not a RARP reply, delete it. */
452 	if (rarp->ar_op != htons(ARPOP_RREPLY))
453 		goto drop;
454 
455 	/* If it's not Ethernet, delete it. */
456 	if (rarp->ar_pro != htons(ETH_P_IP))
457 		goto drop;
458 
459 	if (!pskb_may_pull(skb,
460 			   sizeof(struct arphdr) +
461 			   (2 * dev->addr_len) +
462 			   (2 * 4)))
463 		goto drop;
464 
465 	/* OK, it is all there and looks valid, process... */
466 	rarp = (struct arphdr *)skb_transport_header(skb);
467 	rarp_ptr = (unsigned char *) (rarp + 1);
468 
469 	/* One reply at a time, please. */
470 	spin_lock(&ic_recv_lock);
471 
472 	/* If we already have a reply, just drop the packet */
473 	if (ic_got_reply)
474 		goto drop_unlock;
475 
476 	/* Find the ic_device that the packet arrived on */
477 	d = ic_first_dev;
478 	while (d && d->dev != dev)
479 		d = d->next;
480 	if (!d)
481 		goto drop_unlock;	/* should never happen */
482 
483 	/* Extract variable-width fields */
484 	sha = rarp_ptr;
485 	rarp_ptr += dev->addr_len;
486 	memcpy(&sip, rarp_ptr, 4);
487 	rarp_ptr += 4;
488 	tha = rarp_ptr;
489 	rarp_ptr += dev->addr_len;
490 	memcpy(&tip, rarp_ptr, 4);
491 
492 	/* Discard packets which are not meant for us. */
493 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
494 		goto drop_unlock;
495 
496 	/* Discard packets which are not from specified server. */
497 	if (ic_servaddr != NONE && ic_servaddr != sip)
498 		goto drop_unlock;
499 
500 	/* We have a winner! */
501 	ic_dev = dev;
502 	if (ic_myaddr == NONE)
503 		ic_myaddr = tip;
504 	ic_servaddr = sip;
505 	ic_got_reply = IC_RARP;
506 
507 drop_unlock:
508 	/* Show's over.  Nothing to see here.  */
509 	spin_unlock(&ic_recv_lock);
510 
511 drop:
512 	/* Throw the packet out. */
513 	kfree_skb(skb);
514 	return 0;
515 }
516 
517 
518 /*
519  *  Send RARP request packet over a single interface.
520  */
521 static void __init ic_rarp_send_if(struct ic_device *d)
522 {
523 	struct net_device *dev = d->dev;
524 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
525 		 dev->dev_addr, dev->dev_addr);
526 }
527 #endif
528 
529 /*
530  *	DHCP/BOOTP support.
531  */
532 
533 #ifdef IPCONFIG_BOOTP
534 
535 struct bootp_pkt {		/* BOOTP packet format */
536 	struct iphdr iph;	/* IP header */
537 	struct udphdr udph;	/* UDP header */
538 	u8 op;			/* 1=request, 2=reply */
539 	u8 htype;		/* HW address type */
540 	u8 hlen;		/* HW address length */
541 	u8 hops;		/* Used only by gateways */
542 	__be32 xid;		/* Transaction ID */
543 	__be16 secs;		/* Seconds since we started */
544 	__be16 flags;		/* Just what it says */
545 	__be32 client_ip;		/* Client's IP address if known */
546 	__be32 your_ip;		/* Assigned IP address */
547 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
548 	__be32 relay_ip;		/* IP address of BOOTP relay */
549 	u8 hw_addr[16];		/* Client's HW address */
550 	u8 serv_name[64];	/* Server host name */
551 	u8 boot_file[128];	/* Name of boot file */
552 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
553 };
554 
555 /* packet ops */
556 #define BOOTP_REQUEST	1
557 #define BOOTP_REPLY	2
558 
559 /* DHCP message types */
560 #define DHCPDISCOVER	1
561 #define DHCPOFFER	2
562 #define DHCPREQUEST	3
563 #define DHCPDECLINE	4
564 #define DHCPACK		5
565 #define DHCPNAK		6
566 #define DHCPRELEASE	7
567 #define DHCPINFORM	8
568 
569 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
570 
571 static struct packet_type bootp_packet_type __initdata = {
572 	.type =	__constant_htons(ETH_P_IP),
573 	.func =	ic_bootp_recv,
574 };
575 
576 
577 /*
578  *  Initialize DHCP/BOOTP extension fields in the request.
579  */
580 
581 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
582 
583 #ifdef IPCONFIG_DHCP
584 
585 static void __init
586 ic_dhcp_init_options(u8 *options)
587 {
588 	u8 mt = ((ic_servaddr == NONE)
589 		 ? DHCPDISCOVER : DHCPREQUEST);
590 	u8 *e = options;
591 
592 #ifdef IPCONFIG_DEBUG
593 	printk("DHCP: Sending message type %d\n", mt);
594 #endif
595 
596 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
597 	e += 4;
598 
599 	*e++ = 53;		/* DHCP message type */
600 	*e++ = 1;
601 	*e++ = mt;
602 
603 	if (mt == DHCPREQUEST) {
604 		*e++ = 54;	/* Server ID (IP address) */
605 		*e++ = 4;
606 		memcpy(e, &ic_servaddr, 4);
607 		e += 4;
608 
609 		*e++ = 50;	/* Requested IP address */
610 		*e++ = 4;
611 		memcpy(e, &ic_myaddr, 4);
612 		e += 4;
613 	}
614 
615 	/* always? */
616 	{
617 		static const u8 ic_req_params[] = {
618 			1,	/* Subnet mask */
619 			3,	/* Default gateway */
620 			6,	/* DNS server */
621 			12,	/* Host name */
622 			15,	/* Domain name */
623 			17,	/* Boot path */
624 			40,	/* NIS domain name */
625 		};
626 
627 		*e++ = 55;	/* Parameter request list */
628 		*e++ = sizeof(ic_req_params);
629 		memcpy(e, ic_req_params, sizeof(ic_req_params));
630 		e += sizeof(ic_req_params);
631 	}
632 
633 	*e++ = 255;	/* End of the list */
634 }
635 
636 #endif /* IPCONFIG_DHCP */
637 
638 static void __init ic_bootp_init_ext(u8 *e)
639 {
640 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
641 	e += 4;
642 	*e++ = 1;		/* Subnet mask request */
643 	*e++ = 4;
644 	e += 4;
645 	*e++ = 3;		/* Default gateway request */
646 	*e++ = 4;
647 	e += 4;
648 	*e++ = 5;		/* Name server request */
649 	*e++ = 8;
650 	e += 8;
651 	*e++ = 12;		/* Host name request */
652 	*e++ = 32;
653 	e += 32;
654 	*e++ = 40;		/* NIS Domain name request */
655 	*e++ = 32;
656 	e += 32;
657 	*e++ = 17;		/* Boot path */
658 	*e++ = 40;
659 	e += 40;
660 
661 	*e++ = 57;		/* set extension buffer size for reply */
662 	*e++ = 2;
663 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
664 	*e++ = 150;
665 
666 	*e++ = 255;		/* End of the list */
667 }
668 
669 
670 /*
671  *  Initialize the DHCP/BOOTP mechanism.
672  */
673 static inline void ic_bootp_init(void)
674 {
675 	int i;
676 
677 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
678 		ic_nameservers[i] = NONE;
679 
680 	dev_add_pack(&bootp_packet_type);
681 }
682 
683 
684 /*
685  *  DHCP/BOOTP cleanup.
686  */
687 static inline void ic_bootp_cleanup(void)
688 {
689 	dev_remove_pack(&bootp_packet_type);
690 }
691 
692 
693 /*
694  *  Send DHCP/BOOTP request to single interface.
695  */
696 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
697 {
698 	struct net_device *dev = d->dev;
699 	struct sk_buff *skb;
700 	struct bootp_pkt *b;
701 	int hh_len = LL_RESERVED_SPACE(dev);
702 	struct iphdr *h;
703 
704 	/* Allocate packet */
705 	skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
706 	if (!skb)
707 		return;
708 	skb_reserve(skb, hh_len);
709 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
710 	memset(b, 0, sizeof(struct bootp_pkt));
711 
712 	/* Construct IP header */
713 	skb_reset_network_header(skb);
714 	h = ip_hdr(skb);
715 	h->version = 4;
716 	h->ihl = 5;
717 	h->tot_len = htons(sizeof(struct bootp_pkt));
718 	h->frag_off = htons(IP_DF);
719 	h->ttl = 64;
720 	h->protocol = IPPROTO_UDP;
721 	h->daddr = htonl(INADDR_BROADCAST);
722 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
723 
724 	/* Construct UDP header */
725 	b->udph.source = htons(68);
726 	b->udph.dest = htons(67);
727 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
728 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
729 
730 	/* Construct DHCP/BOOTP header */
731 	b->op = BOOTP_REQUEST;
732 	if (dev->type < 256) /* check for false types */
733 		b->htype = dev->type;
734 	else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
735 		b->htype = ARPHRD_IEEE802;
736 	else if (dev->type == ARPHRD_FDDI)
737 		b->htype = ARPHRD_ETHER;
738 	else {
739 		printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
740 		b->htype = dev->type; /* can cause undefined behavior */
741 	}
742 	b->hlen = dev->addr_len;
743 	b->your_ip = NONE;
744 	b->server_ip = NONE;
745 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
746 	b->secs = htons(jiffies_diff / HZ);
747 	b->xid = d->xid;
748 
749 	/* add DHCP options or BOOTP extensions */
750 #ifdef IPCONFIG_DHCP
751 	if (ic_proto_enabled & IC_USE_DHCP)
752 		ic_dhcp_init_options(b->exten);
753 	else
754 #endif
755 		ic_bootp_init_ext(b->exten);
756 
757 	/* Chain packet down the line... */
758 	skb->dev = dev;
759 	skb->protocol = htons(ETH_P_IP);
760 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
761 			    dev->broadcast, dev->dev_addr, skb->len) < 0 ||
762 	    dev_queue_xmit(skb) < 0)
763 		printk("E");
764 }
765 
766 
767 /*
768  *  Copy BOOTP-supplied string if not already set.
769  */
770 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
771 {
772 	if (!len)
773 		return 0;
774 	if (len > max-1)
775 		len = max-1;
776 	memcpy(dest, src, len);
777 	dest[len] = '\0';
778 	return 1;
779 }
780 
781 
782 /*
783  *  Process BOOTP extensions.
784  */
785 static void __init ic_do_bootp_ext(u8 *ext)
786 {
787        u8 servers;
788        int i;
789 
790 #ifdef IPCONFIG_DEBUG
791 	u8 *c;
792 
793 	printk("DHCP/BOOTP: Got extension %d:",*ext);
794 	for (c=ext+2; c<ext+2+ext[1]; c++)
795 		printk(" %02x", *c);
796 	printk("\n");
797 #endif
798 
799 	switch (*ext++) {
800 		case 1:		/* Subnet mask */
801 			if (ic_netmask == NONE)
802 				memcpy(&ic_netmask, ext+1, 4);
803 			break;
804 		case 3:		/* Default gateway */
805 			if (ic_gateway == NONE)
806 				memcpy(&ic_gateway, ext+1, 4);
807 			break;
808 		case 6:		/* DNS server */
809 			servers= *ext/4;
810 			if (servers > CONF_NAMESERVERS_MAX)
811 				servers = CONF_NAMESERVERS_MAX;
812 			for (i = 0; i < servers; i++) {
813 				if (ic_nameservers[i] == NONE)
814 					memcpy(&ic_nameservers[i], ext+1+4*i, 4);
815 			}
816 			break;
817 		case 12:	/* Host name */
818 			ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
819 			ic_host_name_set = 1;
820 			break;
821 		case 15:	/* Domain name (DNS) */
822 			ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
823 			break;
824 		case 17:	/* Root path */
825 			if (!root_server_path[0])
826 				ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
827 			break;
828 		case 40:	/* NIS Domain name (_not_ DNS) */
829 			ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
830 			break;
831 	}
832 }
833 
834 
835 /*
836  *  Receive BOOTP reply.
837  */
838 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
839 {
840 	struct bootp_pkt *b;
841 	struct iphdr *h;
842 	struct ic_device *d;
843 	int len, ext_len;
844 
845 	if (dev->nd_net != &init_net)
846 		goto drop;
847 
848 	/* Perform verifications before taking the lock.  */
849 	if (skb->pkt_type == PACKET_OTHERHOST)
850 		goto drop;
851 
852 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
853 		return NET_RX_DROP;
854 
855 	if (!pskb_may_pull(skb,
856 			   sizeof(struct iphdr) +
857 			   sizeof(struct udphdr)))
858 		goto drop;
859 
860 	b = (struct bootp_pkt *)skb_network_header(skb);
861 	h = &b->iph;
862 
863 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
864 		goto drop;
865 
866 	/* Fragments are not supported */
867 	if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
868 		if (net_ratelimit())
869 			printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
870 			       "reply.\n");
871 		goto drop;
872 	}
873 
874 	if (skb->len < ntohs(h->tot_len))
875 		goto drop;
876 
877 	if (ip_fast_csum((char *) h, h->ihl))
878 		goto drop;
879 
880 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
881 		goto drop;
882 
883 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
884 		goto drop;
885 
886 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
887 	ext_len = len - (sizeof(*b) -
888 			 sizeof(struct iphdr) -
889 			 sizeof(struct udphdr) -
890 			 sizeof(b->exten));
891 	if (ext_len < 0)
892 		goto drop;
893 
894 	/* Ok the front looks good, make sure we can get at the rest.  */
895 	if (!pskb_may_pull(skb, skb->len))
896 		goto drop;
897 
898 	b = (struct bootp_pkt *)skb_network_header(skb);
899 	h = &b->iph;
900 
901 	/* One reply at a time, please. */
902 	spin_lock(&ic_recv_lock);
903 
904 	/* If we already have a reply, just drop the packet */
905 	if (ic_got_reply)
906 		goto drop_unlock;
907 
908 	/* Find the ic_device that the packet arrived on */
909 	d = ic_first_dev;
910 	while (d && d->dev != dev)
911 		d = d->next;
912 	if (!d)
913 		goto drop_unlock;  /* should never happen */
914 
915 	/* Is it a reply to our BOOTP request? */
916 	if (b->op != BOOTP_REPLY ||
917 	    b->xid != d->xid) {
918 		if (net_ratelimit())
919 			printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
920 			       "op[%x] xid[%x]\n",
921 			       b->op, b->xid);
922 		goto drop_unlock;
923 	}
924 
925 	/* Parse extensions */
926 	if (ext_len >= 4 &&
927 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
928 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
929 		u8 *ext;
930 
931 #ifdef IPCONFIG_DHCP
932 		if (ic_proto_enabled & IC_USE_DHCP) {
933 			__be32 server_id = NONE;
934 			int mt = 0;
935 
936 			ext = &b->exten[4];
937 			while (ext < end && *ext != 0xff) {
938 				u8 *opt = ext++;
939 				if (*opt == 0)	/* Padding */
940 					continue;
941 				ext += *ext + 1;
942 				if (ext >= end)
943 					break;
944 				switch (*opt) {
945 				case 53:	/* Message type */
946 					if (opt[1])
947 						mt = opt[2];
948 					break;
949 				case 54:	/* Server ID (IP address) */
950 					if (opt[1] >= 4)
951 						memcpy(&server_id, opt + 2, 4);
952 					break;
953 				}
954 			}
955 
956 #ifdef IPCONFIG_DEBUG
957 			printk("DHCP: Got message type %d\n", mt);
958 #endif
959 
960 			switch (mt) {
961 			case DHCPOFFER:
962 				/* While in the process of accepting one offer,
963 				 * ignore all others.
964 				 */
965 				if (ic_myaddr != NONE)
966 					goto drop_unlock;
967 
968 				/* Let's accept that offer. */
969 				ic_myaddr = b->your_ip;
970 				ic_servaddr = server_id;
971 #ifdef IPCONFIG_DEBUG
972 				printk("DHCP: Offered address %u.%u.%u.%u",
973 				       NIPQUAD(ic_myaddr));
974 				printk(" by server %u.%u.%u.%u\n",
975 				       NIPQUAD(ic_servaddr));
976 #endif
977 				/* The DHCP indicated server address takes
978 				 * precedence over the bootp header one if
979 				 * they are different.
980 				 */
981 				if ((server_id != NONE) &&
982 				    (b->server_ip != server_id))
983 					b->server_ip = ic_servaddr;
984 				break;
985 
986 			case DHCPACK:
987 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
988 					goto drop_unlock;
989 
990 				/* Yeah! */
991 				break;
992 
993 			default:
994 				/* Urque.  Forget it*/
995 				ic_myaddr = NONE;
996 				ic_servaddr = NONE;
997 				goto drop_unlock;
998 			}
999 
1000 			ic_dhcp_msgtype = mt;
1001 
1002 		}
1003 #endif /* IPCONFIG_DHCP */
1004 
1005 		ext = &b->exten[4];
1006 		while (ext < end && *ext != 0xff) {
1007 			u8 *opt = ext++;
1008 			if (*opt == 0)	/* Padding */
1009 				continue;
1010 			ext += *ext + 1;
1011 			if (ext < end)
1012 				ic_do_bootp_ext(opt);
1013 		}
1014 	}
1015 
1016 	/* We have a winner! */
1017 	ic_dev = dev;
1018 	ic_myaddr = b->your_ip;
1019 	ic_servaddr = b->server_ip;
1020 	if (ic_gateway == NONE && b->relay_ip)
1021 		ic_gateway = b->relay_ip;
1022 	if (ic_nameservers[0] == NONE)
1023 		ic_nameservers[0] = ic_servaddr;
1024 	ic_got_reply = IC_BOOTP;
1025 
1026 drop_unlock:
1027 	/* Show's over.  Nothing to see here.  */
1028 	spin_unlock(&ic_recv_lock);
1029 
1030 drop:
1031 	/* Throw the packet out. */
1032 	kfree_skb(skb);
1033 
1034 	return 0;
1035 }
1036 
1037 
1038 #endif
1039 
1040 
1041 /*
1042  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1043  */
1044 
1045 #ifdef IPCONFIG_DYNAMIC
1046 
1047 static int __init ic_dynamic(void)
1048 {
1049 	int retries;
1050 	struct ic_device *d;
1051 	unsigned long start_jiffies, timeout, jiff;
1052 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1053 	int do_rarp = ic_proto_have_if & IC_RARP;
1054 
1055 	/*
1056 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1057 	 * This routine gets only called when some pieces of information
1058 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1059 	 */
1060 	if (!ic_proto_enabled) {
1061 		printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1062 		return -1;
1063 	}
1064 
1065 #ifdef IPCONFIG_BOOTP
1066 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1067 		printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1068 #endif
1069 #ifdef IPCONFIG_RARP
1070 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1071 		printk(KERN_ERR "RARP: No suitable device found.\n");
1072 #endif
1073 
1074 	if (!ic_proto_have_if)
1075 		/* Error message already printed */
1076 		return -1;
1077 
1078 	/*
1079 	 * Setup protocols
1080 	 */
1081 #ifdef IPCONFIG_BOOTP
1082 	if (do_bootp)
1083 		ic_bootp_init();
1084 #endif
1085 #ifdef IPCONFIG_RARP
1086 	if (do_rarp)
1087 		ic_rarp_init();
1088 #endif
1089 
1090 	/*
1091 	 * Send requests and wait, until we get an answer. This loop
1092 	 * seems to be a terrible waste of CPU time, but actually there is
1093 	 * only one process running at all, so we don't need to use any
1094 	 * scheduler functions.
1095 	 * [Actually we could now, but the nothing else running note still
1096 	 *  applies.. - AC]
1097 	 */
1098 	printk(KERN_NOTICE "Sending %s%s%s requests .",
1099 	       do_bootp
1100 		? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1101 	       (do_bootp && do_rarp) ? " and " : "",
1102 	       do_rarp ? "RARP" : "");
1103 
1104 	start_jiffies = jiffies;
1105 	d = ic_first_dev;
1106 	retries = CONF_SEND_RETRIES;
1107 	get_random_bytes(&timeout, sizeof(timeout));
1108 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1109 	for (;;) {
1110 #ifdef IPCONFIG_BOOTP
1111 		if (do_bootp && (d->able & IC_BOOTP))
1112 			ic_bootp_send_if(d, jiffies - start_jiffies);
1113 #endif
1114 #ifdef IPCONFIG_RARP
1115 		if (do_rarp && (d->able & IC_RARP))
1116 			ic_rarp_send_if(d);
1117 #endif
1118 
1119 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1120 		while (time_before(jiffies, jiff) && !ic_got_reply)
1121 			schedule_timeout_uninterruptible(1);
1122 #ifdef IPCONFIG_DHCP
1123 		/* DHCP isn't done until we get a DHCPACK. */
1124 		if ((ic_got_reply & IC_BOOTP)
1125 		    && (ic_proto_enabled & IC_USE_DHCP)
1126 		    && ic_dhcp_msgtype != DHCPACK)
1127 		{
1128 			ic_got_reply = 0;
1129 			printk(",");
1130 			continue;
1131 		}
1132 #endif /* IPCONFIG_DHCP */
1133 
1134 		if (ic_got_reply) {
1135 			printk(" OK\n");
1136 			break;
1137 		}
1138 
1139 		if ((d = d->next))
1140 			continue;
1141 
1142 		if (! --retries) {
1143 			printk(" timed out!\n");
1144 			break;
1145 		}
1146 
1147 		d = ic_first_dev;
1148 
1149 		timeout = timeout CONF_TIMEOUT_MULT;
1150 		if (timeout > CONF_TIMEOUT_MAX)
1151 			timeout = CONF_TIMEOUT_MAX;
1152 
1153 		printk(".");
1154 	}
1155 
1156 #ifdef IPCONFIG_BOOTP
1157 	if (do_bootp)
1158 		ic_bootp_cleanup();
1159 #endif
1160 #ifdef IPCONFIG_RARP
1161 	if (do_rarp)
1162 		ic_rarp_cleanup();
1163 #endif
1164 
1165 	if (!ic_got_reply) {
1166 		ic_myaddr = NONE;
1167 		return -1;
1168 	}
1169 
1170 	printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1171 		((ic_got_reply & IC_RARP) ? "RARP"
1172 		 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1173 		NIPQUAD(ic_servaddr));
1174 	printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1175 
1176 	return 0;
1177 }
1178 
1179 #endif /* IPCONFIG_DYNAMIC */
1180 
1181 #ifdef CONFIG_PROC_FS
1182 
1183 static int pnp_seq_show(struct seq_file *seq, void *v)
1184 {
1185 	int i;
1186 
1187 	if (ic_proto_used & IC_PROTO)
1188 		seq_printf(seq, "#PROTO: %s\n",
1189 			   (ic_proto_used & IC_RARP) ? "RARP"
1190 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1191 	else
1192 		seq_puts(seq, "#MANUAL\n");
1193 
1194 	if (ic_domain[0])
1195 		seq_printf(seq,
1196 			   "domain %s\n", ic_domain);
1197 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1198 		if (ic_nameservers[i] != NONE)
1199 			seq_printf(seq,
1200 				   "nameserver %u.%u.%u.%u\n",
1201 				   NIPQUAD(ic_nameservers[i]));
1202 	}
1203 	if (ic_servaddr != NONE)
1204 		seq_printf(seq,
1205 			   "bootserver %u.%u.%u.%u\n",
1206 			   NIPQUAD(ic_servaddr));
1207 	return 0;
1208 }
1209 
1210 static int pnp_seq_open(struct inode *indoe, struct file *file)
1211 {
1212 	return single_open(file, pnp_seq_show, NULL);
1213 }
1214 
1215 static const struct file_operations pnp_seq_fops = {
1216 	.owner		= THIS_MODULE,
1217 	.open		= pnp_seq_open,
1218 	.read		= seq_read,
1219 	.llseek		= seq_lseek,
1220 	.release	= single_release,
1221 };
1222 #endif /* CONFIG_PROC_FS */
1223 
1224 /*
1225  *  Extract IP address from the parameter string if needed. Note that we
1226  *  need to have root_server_addr set _before_ IPConfig gets called as it
1227  *  can override it.
1228  */
1229 __be32 __init root_nfs_parse_addr(char *name)
1230 {
1231 	__be32 addr;
1232 	int octets = 0;
1233 	char *cp, *cq;
1234 
1235 	cp = cq = name;
1236 	while (octets < 4) {
1237 		while (*cp >= '0' && *cp <= '9')
1238 			cp++;
1239 		if (cp == cq || cp - cq > 3)
1240 			break;
1241 		if (*cp == '.' || octets == 3)
1242 			octets++;
1243 		if (octets < 4)
1244 			cp++;
1245 		cq = cp;
1246 	}
1247 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1248 		if (*cp == ':')
1249 			*cp++ = '\0';
1250 		addr = in_aton(name);
1251 		memmove(name, cp, strlen(cp) + 1);
1252 	} else
1253 		addr = NONE;
1254 
1255 	return addr;
1256 }
1257 
1258 /*
1259  *	IP Autoconfig dispatcher.
1260  */
1261 
1262 static int __init ip_auto_config(void)
1263 {
1264 	__be32 addr;
1265 
1266 #ifdef CONFIG_PROC_FS
1267 	proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1268 #endif /* CONFIG_PROC_FS */
1269 
1270 	if (!ic_enable)
1271 		return 0;
1272 
1273 	DBG(("IP-Config: Entered.\n"));
1274 #ifdef IPCONFIG_DYNAMIC
1275  try_try_again:
1276 #endif
1277 	/* Give hardware a chance to settle */
1278 	msleep(CONF_PRE_OPEN);
1279 
1280 	/* Setup all network devices */
1281 	if (ic_open_devs() < 0)
1282 		return -1;
1283 
1284 	/* Give drivers a chance to settle */
1285 	ssleep(CONF_POST_OPEN);
1286 
1287 	/*
1288 	 * If the config information is insufficient (e.g., our IP address or
1289 	 * IP address of the boot server is missing or we have multiple network
1290 	 * interfaces and no default was set), use BOOTP or RARP to get the
1291 	 * missing values.
1292 	 */
1293 	if (ic_myaddr == NONE ||
1294 #ifdef CONFIG_ROOT_NFS
1295 	    (root_server_addr == NONE
1296 	     && ic_servaddr == NONE
1297 	     && ROOT_DEV == Root_NFS) ||
1298 #endif
1299 	    ic_first_dev->next) {
1300 #ifdef IPCONFIG_DYNAMIC
1301 
1302 		int retries = CONF_OPEN_RETRIES;
1303 
1304 		if (ic_dynamic() < 0) {
1305 			ic_close_devs();
1306 
1307 			/*
1308 			 * I don't know why, but sometimes the
1309 			 * eepro100 driver (at least) gets upset and
1310 			 * doesn't work the first time it's opened.
1311 			 * But then if you close it and reopen it, it
1312 			 * works just fine.  So we need to try that at
1313 			 * least once before giving up.
1314 			 *
1315 			 * Also, if the root will be NFS-mounted, we
1316 			 * have nowhere to go if DHCP fails.  So we
1317 			 * just have to keep trying forever.
1318 			 *
1319 			 * 				-- Chip
1320 			 */
1321 #ifdef CONFIG_ROOT_NFS
1322 			if (ROOT_DEV ==  Root_NFS) {
1323 				printk(KERN_ERR
1324 					"IP-Config: Retrying forever (NFS root)...\n");
1325 				goto try_try_again;
1326 			}
1327 #endif
1328 
1329 			if (--retries) {
1330 				printk(KERN_ERR
1331 				       "IP-Config: Reopening network devices...\n");
1332 				goto try_try_again;
1333 			}
1334 
1335 			/* Oh, well.  At least we tried. */
1336 			printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1337 			return -1;
1338 		}
1339 #else /* !DYNAMIC */
1340 		printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1341 		ic_close_devs();
1342 		return -1;
1343 #endif /* IPCONFIG_DYNAMIC */
1344 	} else {
1345 		/* Device selected manually or only one device -> use it */
1346 		ic_dev = ic_first_dev->dev;
1347 	}
1348 
1349 	addr = root_nfs_parse_addr(root_server_path);
1350 	if (root_server_addr == NONE)
1351 		root_server_addr = addr;
1352 
1353 	/*
1354 	 * Use defaults whereever applicable.
1355 	 */
1356 	if (ic_defaults() < 0)
1357 		return -1;
1358 
1359 	/*
1360 	 * Close all network devices except the device we've
1361 	 * autoconfigured and set up routes.
1362 	 */
1363 	ic_close_devs();
1364 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1365 		return -1;
1366 
1367 	/*
1368 	 * Record which protocol was actually used.
1369 	 */
1370 #ifdef IPCONFIG_DYNAMIC
1371 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1372 #endif
1373 
1374 #ifndef IPCONFIG_SILENT
1375 	/*
1376 	 * Clue in the operator.
1377 	 */
1378 	printk("IP-Config: Complete:");
1379 	printk("\n      device=%s", ic_dev->name);
1380 	printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1381 	printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1382 	printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1383 	printk(",\n     host=%s, domain=%s, nis-domain=%s",
1384 	       utsname()->nodename, ic_domain, utsname()->domainname);
1385 	printk(",\n     bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1386 	printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1387 	printk(", rootpath=%s", root_server_path);
1388 	printk("\n");
1389 #endif /* !SILENT */
1390 
1391 	return 0;
1392 }
1393 
1394 late_initcall(ip_auto_config);
1395 
1396 
1397 /*
1398  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1399  *  command line parameter. It consists of option fields separated by colons in
1400  *  the following order:
1401  *
1402  *  <client-ip>:<server-ip>:<gw-ip>:<netmask>:<host name>:<device>:<PROTO>
1403  *
1404  *  Any of the fields can be empty which means to use a default value:
1405  *	<client-ip>	- address given by BOOTP or RARP
1406  *	<server-ip>	- address of host returning BOOTP or RARP packet
1407  *	<gw-ip>		- none, or the address returned by BOOTP
1408  *	<netmask>	- automatically determined from <client-ip>, or the
1409  *			  one returned by BOOTP
1410  *	<host name>	- <client-ip> in ASCII notation, or the name returned
1411  *			  by BOOTP
1412  *	<device>	- use all available devices
1413  *	<PROTO>:
1414  *	   off|none	    - don't do autoconfig at all (DEFAULT)
1415  *	   on|any           - use any configured protocol
1416  *	   dhcp|bootp|rarp  - use only the specified protocol
1417  *	   both             - use both BOOTP and RARP (not DHCP)
1418  */
1419 static int __init ic_proto_name(char *name)
1420 {
1421 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1422 		return 1;
1423 	}
1424 #ifdef CONFIG_IP_PNP_DHCP
1425 	else if (!strcmp(name, "dhcp")) {
1426 		ic_proto_enabled &= ~IC_RARP;
1427 		return 1;
1428 	}
1429 #endif
1430 #ifdef CONFIG_IP_PNP_BOOTP
1431 	else if (!strcmp(name, "bootp")) {
1432 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1433 		return 1;
1434 	}
1435 #endif
1436 #ifdef CONFIG_IP_PNP_RARP
1437 	else if (!strcmp(name, "rarp")) {
1438 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1439 		return 1;
1440 	}
1441 #endif
1442 #ifdef IPCONFIG_DYNAMIC
1443 	else if (!strcmp(name, "both")) {
1444 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1445 		return 1;
1446 	}
1447 #endif
1448 	return 0;
1449 }
1450 
1451 static int __init ip_auto_config_setup(char *addrs)
1452 {
1453 	char *cp, *ip, *dp;
1454 	int num = 0;
1455 
1456 	ic_set_manually = 1;
1457 
1458 	ic_enable = (*addrs &&
1459 		(strcmp(addrs, "off") != 0) &&
1460 		(strcmp(addrs, "none") != 0));
1461 	if (!ic_enable)
1462 		return 1;
1463 
1464 	if (ic_proto_name(addrs))
1465 		return 1;
1466 
1467 	/* Parse the whole string */
1468 	ip = addrs;
1469 	while (ip && *ip) {
1470 		if ((cp = strchr(ip, ':')))
1471 			*cp++ = '\0';
1472 		if (strlen(ip) > 0) {
1473 			DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1474 			switch (num) {
1475 			case 0:
1476 				if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1477 					ic_myaddr = NONE;
1478 				break;
1479 			case 1:
1480 				if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1481 					ic_servaddr = NONE;
1482 				break;
1483 			case 2:
1484 				if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1485 					ic_gateway = NONE;
1486 				break;
1487 			case 3:
1488 				if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1489 					ic_netmask = NONE;
1490 				break;
1491 			case 4:
1492 				if ((dp = strchr(ip, '.'))) {
1493 					*dp++ = '\0';
1494 					strlcpy(utsname()->domainname, dp,
1495 						sizeof(utsname()->domainname));
1496 				}
1497 				strlcpy(utsname()->nodename, ip,
1498 					sizeof(utsname()->nodename));
1499 				ic_host_name_set = 1;
1500 				break;
1501 			case 5:
1502 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1503 				break;
1504 			case 6:
1505 				ic_proto_name(ip);
1506 				break;
1507 			}
1508 		}
1509 		ip = cp;
1510 		num++;
1511 	}
1512 
1513 	return 1;
1514 }
1515 
1516 static int __init nfsaddrs_config_setup(char *addrs)
1517 {
1518 	return ip_auto_config_setup(addrs);
1519 }
1520 
1521 __setup("ip=", ip_auto_config_setup);
1522 __setup("nfsaddrs=", nfsaddrs_config_setup);
1523