xref: /linux/net/ipv4/ipconfig.c (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
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/config.h>
35 #include <linux/types.h>
36 #include <linux/string.h>
37 #include <linux/kernel.h>
38 #include <linux/jiffies.h>
39 #include <linux/random.h>
40 #include <linux/init.h>
41 #include <linux/utsname.h>
42 #include <linux/in.h>
43 #include <linux/if.h>
44 #include <linux/inet.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/arp.h>
59 #include <net/ip.h>
60 #include <net/ipconfig.h>
61 
62 #include <asm/uaccess.h>
63 #include <net/checksum.h>
64 #include <asm/processor.h>
65 
66 /* Define this to allow debugging output */
67 #undef IPCONFIG_DEBUG
68 
69 #ifdef IPCONFIG_DEBUG
70 #define DBG(x) printk x
71 #else
72 #define DBG(x) do { } while(0)
73 #endif
74 
75 #if defined(CONFIG_IP_PNP_DHCP)
76 #define IPCONFIG_DHCP
77 #endif
78 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
79 #define IPCONFIG_BOOTP
80 #endif
81 #if defined(CONFIG_IP_PNP_RARP)
82 #define IPCONFIG_RARP
83 #endif
84 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
85 #define IPCONFIG_DYNAMIC
86 #endif
87 
88 /* Define the friendly delay before and after opening net devices */
89 #define CONF_PRE_OPEN		500	/* Before opening: 1/2 second */
90 #define CONF_POST_OPEN		1	/* After opening: 1 second */
91 
92 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
93 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
94 #define CONF_SEND_RETRIES 	6	/* Send six requests per open */
95 #define CONF_INTER_TIMEOUT	(HZ/2)	/* Inter-device timeout: 1/2 second */
96 #define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
97 #define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
98 #define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
99 #define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
100 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
101                                            - '3' from resolv.h */
102 
103 
104 /*
105  * Public IP configuration
106  */
107 
108 /* This is used by platforms which might be able to set the ipconfig
109  * variables using firmware environment vars.  If this is set, it will
110  * ignore such firmware variables.
111  */
112 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
113 
114 static int ic_enable __initdata = 0;		/* IP config enabled? */
115 
116 /* Protocol choice */
117 int ic_proto_enabled __initdata = 0
118 #ifdef IPCONFIG_BOOTP
119 			| IC_BOOTP
120 #endif
121 #ifdef CONFIG_IP_PNP_DHCP
122 			| IC_USE_DHCP
123 #endif
124 #ifdef IPCONFIG_RARP
125 			| IC_RARP
126 #endif
127 			;
128 
129 static int ic_host_name_set __initdata = 0;	/* Host name set by us? */
130 
131 u32 ic_myaddr = INADDR_NONE;		/* My IP address */
132 static u32 ic_netmask = INADDR_NONE;	/* Netmask for local subnet */
133 u32 ic_gateway = INADDR_NONE;	/* Gateway IP address */
134 
135 u32 ic_servaddr = INADDR_NONE;	/* Boot server IP address */
136 
137 u32 root_server_addr = INADDR_NONE;	/* Address of NFS server */
138 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
139 
140 /* Persistent data: */
141 
142 static int ic_proto_used;			/* Protocol used, if any */
143 static u32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
144 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
145 
146 /*
147  * Private state.
148  */
149 
150 /* Name of user-selected boot device */
151 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
152 
153 /* Protocols supported by available interfaces */
154 static int ic_proto_have_if __initdata = 0;
155 
156 #ifdef IPCONFIG_DYNAMIC
157 static DEFINE_SPINLOCK(ic_recv_lock);
158 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
159 #endif
160 #ifdef IPCONFIG_DHCP
161 static int ic_dhcp_msgtype __initdata = 0;	/* DHCP msg type received */
162 #endif
163 
164 
165 /*
166  *	Network devices
167  */
168 
169 struct ic_device {
170 	struct ic_device *next;
171 	struct net_device *dev;
172 	unsigned short flags;
173 	short able;
174 	u32 xid;
175 };
176 
177 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
178 static struct net_device *ic_dev __initdata = NULL;	/* Selected device */
179 
180 static int __init ic_open_devs(void)
181 {
182 	struct ic_device *d, **last;
183 	struct net_device *dev;
184 	unsigned short oflags;
185 
186 	last = &ic_first_dev;
187 	rtnl_shlock();
188 
189 	/* bring loopback device up first */
190 	if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0)
191 		printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name);
192 
193 	for (dev = dev_base; dev; dev = dev->next) {
194 		if (dev == &loopback_dev)
195 			continue;
196 		if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
197 		    (!(dev->flags & IFF_LOOPBACK) &&
198 		     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
199 		     strncmp(dev->name, "dummy", 5))) {
200 			int able = 0;
201 			if (dev->mtu >= 364)
202 				able |= IC_BOOTP;
203 			else
204 				printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
205 			if (!(dev->flags & IFF_NOARP))
206 				able |= IC_RARP;
207 			able &= ic_proto_enabled;
208 			if (ic_proto_enabled && !able)
209 				continue;
210 			oflags = dev->flags;
211 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
212 				printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
213 				continue;
214 			}
215 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
216 				rtnl_shunlock();
217 				return -1;
218 			}
219 			d->dev = dev;
220 			*last = d;
221 			last = &d->next;
222 			d->flags = oflags;
223 			d->able = able;
224 			if (able & IC_BOOTP)
225 				get_random_bytes(&d->xid, sizeof(u32));
226 			else
227 				d->xid = 0;
228 			ic_proto_have_if |= able;
229 			DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
230 				dev->name, able, d->xid));
231 		}
232 	}
233 	rtnl_shunlock();
234 
235 	*last = NULL;
236 
237 	if (!ic_first_dev) {
238 		if (user_dev_name[0])
239 			printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
240 		else
241 			printk(KERN_ERR "IP-Config: No network devices available.\n");
242 		return -1;
243 	}
244 	return 0;
245 }
246 
247 static void __init ic_close_devs(void)
248 {
249 	struct ic_device *d, *next;
250 	struct net_device *dev;
251 
252 	rtnl_shlock();
253 	next = ic_first_dev;
254 	while ((d = next)) {
255 		next = d->next;
256 		dev = d->dev;
257 		if (dev != ic_dev) {
258 			DBG(("IP-Config: Downing %s\n", dev->name));
259 			dev_change_flags(dev, d->flags);
260 		}
261 		kfree(d);
262 	}
263 	rtnl_shunlock();
264 }
265 
266 /*
267  *	Interface to various network functions.
268  */
269 
270 static inline void
271 set_sockaddr(struct sockaddr_in *sin, u32 addr, u16 port)
272 {
273 	sin->sin_family = AF_INET;
274 	sin->sin_addr.s_addr = addr;
275 	sin->sin_port = port;
276 }
277 
278 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
279 {
280 	int res;
281 
282 	mm_segment_t oldfs = get_fs();
283 	set_fs(get_ds());
284 	res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
285 	set_fs(oldfs);
286 	return res;
287 }
288 
289 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
290 {
291 	int res;
292 
293 	mm_segment_t oldfs = get_fs();
294 	set_fs(get_ds());
295 	res = ip_rt_ioctl(cmd, (void __user *) arg);
296 	set_fs(oldfs);
297 	return res;
298 }
299 
300 /*
301  *	Set up interface addresses and routes.
302  */
303 
304 static int __init ic_setup_if(void)
305 {
306 	struct ifreq ir;
307 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
308 	int err;
309 
310 	memset(&ir, 0, sizeof(ir));
311 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
312 	set_sockaddr(sin, ic_myaddr, 0);
313 	if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
314 		printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
315 		return -1;
316 	}
317 	set_sockaddr(sin, ic_netmask, 0);
318 	if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
319 		printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
320 		return -1;
321 	}
322 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
323 	if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
324 		printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
325 		return -1;
326 	}
327 	return 0;
328 }
329 
330 static int __init ic_setup_routes(void)
331 {
332 	/* No need to setup device routes, only the default route... */
333 
334 	if (ic_gateway != INADDR_NONE) {
335 		struct rtentry rm;
336 		int err;
337 
338 		memset(&rm, 0, sizeof(rm));
339 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
340 			printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
341 			return -1;
342 		}
343 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
344 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
345 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
346 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
347 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
348 			printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
349 			return -1;
350 		}
351 	}
352 
353 	return 0;
354 }
355 
356 /*
357  *	Fill in default values for all missing parameters.
358  */
359 
360 static int __init ic_defaults(void)
361 {
362 	/*
363 	 *	At this point we have no userspace running so need not
364 	 *	claim locks on system_utsname
365 	 */
366 
367 	if (!ic_host_name_set)
368 		sprintf(system_utsname.nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
369 
370 	if (root_server_addr == INADDR_NONE)
371 		root_server_addr = ic_servaddr;
372 
373 	if (ic_netmask == INADDR_NONE) {
374 		if (IN_CLASSA(ntohl(ic_myaddr)))
375 			ic_netmask = htonl(IN_CLASSA_NET);
376 		else if (IN_CLASSB(ntohl(ic_myaddr)))
377 			ic_netmask = htonl(IN_CLASSB_NET);
378 		else if (IN_CLASSC(ntohl(ic_myaddr)))
379 			ic_netmask = htonl(IN_CLASSC_NET);
380 		else {
381 			printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
382 				NIPQUAD(ic_myaddr));
383 			return -1;
384 		}
385 		printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
386 	}
387 
388 	return 0;
389 }
390 
391 /*
392  *	RARP support.
393  */
394 
395 #ifdef IPCONFIG_RARP
396 
397 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
398 
399 static struct packet_type rarp_packet_type __initdata = {
400 	.type =	__constant_htons(ETH_P_RARP),
401 	.func =	ic_rarp_recv,
402 };
403 
404 static inline void ic_rarp_init(void)
405 {
406 	dev_add_pack(&rarp_packet_type);
407 }
408 
409 static inline void ic_rarp_cleanup(void)
410 {
411 	dev_remove_pack(&rarp_packet_type);
412 }
413 
414 /*
415  *  Process received RARP packet.
416  */
417 static int __init
418 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
419 {
420 	struct arphdr *rarp;
421 	unsigned char *rarp_ptr;
422 	unsigned long sip, tip;
423 	unsigned char *sha, *tha;		/* s for "source", t for "target" */
424 	struct ic_device *d;
425 
426 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
427 		return NET_RX_DROP;
428 
429 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
430 		goto drop;
431 
432 	/* Basic sanity checks can be done without the lock.  */
433 	rarp = (struct arphdr *)skb->h.raw;
434 
435 	/* If this test doesn't pass, it's not IP, or we should
436 	 * ignore it anyway.
437 	 */
438 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
439 		goto drop;
440 
441 	/* If it's not a RARP reply, delete it. */
442 	if (rarp->ar_op != htons(ARPOP_RREPLY))
443 		goto drop;
444 
445 	/* If it's not Ethernet, delete it. */
446 	if (rarp->ar_pro != htons(ETH_P_IP))
447 		goto drop;
448 
449 	if (!pskb_may_pull(skb,
450 			   sizeof(struct arphdr) +
451 			   (2 * dev->addr_len) +
452 			   (2 * 4)))
453 		goto drop;
454 
455 	/* OK, it is all there and looks valid, process... */
456 	rarp = (struct arphdr *)skb->h.raw;
457 	rarp_ptr = (unsigned char *) (rarp + 1);
458 
459 	/* One reply at a time, please. */
460 	spin_lock(&ic_recv_lock);
461 
462 	/* If we already have a reply, just drop the packet */
463 	if (ic_got_reply)
464 		goto drop_unlock;
465 
466 	/* Find the ic_device that the packet arrived on */
467 	d = ic_first_dev;
468 	while (d && d->dev != dev)
469 		d = d->next;
470 	if (!d)
471 		goto drop_unlock;	/* should never happen */
472 
473 	/* Extract variable-width fields */
474 	sha = rarp_ptr;
475 	rarp_ptr += dev->addr_len;
476 	memcpy(&sip, rarp_ptr, 4);
477 	rarp_ptr += 4;
478 	tha = rarp_ptr;
479 	rarp_ptr += dev->addr_len;
480 	memcpy(&tip, rarp_ptr, 4);
481 
482 	/* Discard packets which are not meant for us. */
483 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
484 		goto drop_unlock;
485 
486 	/* Discard packets which are not from specified server. */
487 	if (ic_servaddr != INADDR_NONE && ic_servaddr != sip)
488 		goto drop_unlock;
489 
490 	/* We have a winner! */
491 	ic_dev = dev;
492 	if (ic_myaddr == INADDR_NONE)
493 		ic_myaddr = tip;
494 	ic_servaddr = sip;
495 	ic_got_reply = IC_RARP;
496 
497 drop_unlock:
498 	/* Show's over.  Nothing to see here.  */
499 	spin_unlock(&ic_recv_lock);
500 
501 drop:
502 	/* Throw the packet out. */
503 	kfree_skb(skb);
504 	return 0;
505 }
506 
507 
508 /*
509  *  Send RARP request packet over a single interface.
510  */
511 static void __init ic_rarp_send_if(struct ic_device *d)
512 {
513 	struct net_device *dev = d->dev;
514 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
515 		 dev->dev_addr, dev->dev_addr);
516 }
517 #endif
518 
519 /*
520  *	DHCP/BOOTP support.
521  */
522 
523 #ifdef IPCONFIG_BOOTP
524 
525 struct bootp_pkt {		/* BOOTP packet format */
526 	struct iphdr iph;	/* IP header */
527 	struct udphdr udph;	/* UDP header */
528 	u8 op;			/* 1=request, 2=reply */
529 	u8 htype;		/* HW address type */
530 	u8 hlen;		/* HW address length */
531 	u8 hops;		/* Used only by gateways */
532 	u32 xid;		/* Transaction ID */
533 	u16 secs;		/* Seconds since we started */
534 	u16 flags;		/* Just what it says */
535 	u32 client_ip;		/* Client's IP address if known */
536 	u32 your_ip;		/* Assigned IP address */
537 	u32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
538 	u32 relay_ip;		/* IP address of BOOTP relay */
539 	u8 hw_addr[16];		/* Client's HW address */
540 	u8 serv_name[64];	/* Server host name */
541 	u8 boot_file[128];	/* Name of boot file */
542 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
543 };
544 
545 /* packet ops */
546 #define BOOTP_REQUEST	1
547 #define BOOTP_REPLY	2
548 
549 /* DHCP message types */
550 #define DHCPDISCOVER	1
551 #define DHCPOFFER	2
552 #define DHCPREQUEST	3
553 #define DHCPDECLINE	4
554 #define DHCPACK		5
555 #define DHCPNAK		6
556 #define DHCPRELEASE	7
557 #define DHCPINFORM	8
558 
559 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
560 
561 static struct packet_type bootp_packet_type __initdata = {
562 	.type =	__constant_htons(ETH_P_IP),
563 	.func =	ic_bootp_recv,
564 };
565 
566 
567 /*
568  *  Initialize DHCP/BOOTP extension fields in the request.
569  */
570 
571 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
572 
573 #ifdef IPCONFIG_DHCP
574 
575 static void __init
576 ic_dhcp_init_options(u8 *options)
577 {
578 	u8 mt = ((ic_servaddr == INADDR_NONE)
579 		 ? DHCPDISCOVER : DHCPREQUEST);
580 	u8 *e = options;
581 
582 #ifdef IPCONFIG_DEBUG
583 	printk("DHCP: Sending message type %d\n", mt);
584 #endif
585 
586 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
587 	e += 4;
588 
589 	*e++ = 53;		/* DHCP message type */
590 	*e++ = 1;
591 	*e++ = mt;
592 
593 	if (mt == DHCPREQUEST) {
594 		*e++ = 54;	/* Server ID (IP address) */
595 		*e++ = 4;
596 		memcpy(e, &ic_servaddr, 4);
597 		e += 4;
598 
599 		*e++ = 50;	/* Requested IP address */
600 		*e++ = 4;
601 		memcpy(e, &ic_myaddr, 4);
602 		e += 4;
603 	}
604 
605 	/* always? */
606 	{
607 		static const u8 ic_req_params[] = {
608 			1,	/* Subnet mask */
609 			3,	/* Default gateway */
610 			6,	/* DNS server */
611 			12,	/* Host name */
612 			15,	/* Domain name */
613 			17,	/* Boot path */
614 			40,	/* NIS domain name */
615 		};
616 
617 		*e++ = 55;	/* Parameter request list */
618 		*e++ = sizeof(ic_req_params);
619 		memcpy(e, ic_req_params, sizeof(ic_req_params));
620 		e += sizeof(ic_req_params);
621 	}
622 
623 	*e++ = 255;	/* End of the list */
624 }
625 
626 #endif /* IPCONFIG_DHCP */
627 
628 static void __init ic_bootp_init_ext(u8 *e)
629 {
630 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
631 	e += 4;
632 	*e++ = 1;		/* Subnet mask request */
633 	*e++ = 4;
634 	e += 4;
635 	*e++ = 3;		/* Default gateway request */
636 	*e++ = 4;
637 	e += 4;
638 	*e++ = 5;		/* Name server request */
639 	*e++ = 8;
640 	e += 8;
641 	*e++ = 12;		/* Host name request */
642 	*e++ = 32;
643 	e += 32;
644 	*e++ = 40;		/* NIS Domain name request */
645 	*e++ = 32;
646 	e += 32;
647 	*e++ = 17;		/* Boot path */
648 	*e++ = 40;
649 	e += 40;
650 
651 	*e++ = 57;		/* set extension buffer size for reply */
652 	*e++ = 2;
653 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
654 	*e++ = 150;
655 
656 	*e++ = 255;		/* End of the list */
657 }
658 
659 
660 /*
661  *  Initialize the DHCP/BOOTP mechanism.
662  */
663 static inline void ic_bootp_init(void)
664 {
665 	int i;
666 
667 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
668 		ic_nameservers[i] = INADDR_NONE;
669 
670 	dev_add_pack(&bootp_packet_type);
671 }
672 
673 
674 /*
675  *  DHCP/BOOTP cleanup.
676  */
677 static inline void ic_bootp_cleanup(void)
678 {
679 	dev_remove_pack(&bootp_packet_type);
680 }
681 
682 
683 /*
684  *  Send DHCP/BOOTP request to single interface.
685  */
686 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
687 {
688 	struct net_device *dev = d->dev;
689 	struct sk_buff *skb;
690 	struct bootp_pkt *b;
691 	int hh_len = LL_RESERVED_SPACE(dev);
692 	struct iphdr *h;
693 
694 	/* Allocate packet */
695 	skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
696 	if (!skb)
697 		return;
698 	skb_reserve(skb, hh_len);
699 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
700 	memset(b, 0, sizeof(struct bootp_pkt));
701 
702 	/* Construct IP header */
703 	skb->nh.iph = h = &b->iph;
704 	h->version = 4;
705 	h->ihl = 5;
706 	h->tot_len = htons(sizeof(struct bootp_pkt));
707 	h->frag_off = htons(IP_DF);
708 	h->ttl = 64;
709 	h->protocol = IPPROTO_UDP;
710 	h->daddr = INADDR_BROADCAST;
711 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
712 
713 	/* Construct UDP header */
714 	b->udph.source = htons(68);
715 	b->udph.dest = htons(67);
716 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
717 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
718 
719 	/* Construct DHCP/BOOTP header */
720 	b->op = BOOTP_REQUEST;
721 	if (dev->type < 256) /* check for false types */
722 		b->htype = dev->type;
723 	else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
724 		b->htype = ARPHRD_IEEE802;
725 	else if (dev->type == ARPHRD_FDDI)
726 		b->htype = ARPHRD_ETHER;
727 	else {
728 		printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
729 		b->htype = dev->type; /* can cause undefined behavior */
730 	}
731 	b->hlen = dev->addr_len;
732 	b->your_ip = INADDR_NONE;
733 	b->server_ip = INADDR_NONE;
734 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
735 	b->secs = htons(jiffies_diff / HZ);
736 	b->xid = d->xid;
737 
738 	/* add DHCP options or BOOTP extensions */
739 #ifdef IPCONFIG_DHCP
740 	if (ic_proto_enabled & IC_USE_DHCP)
741 		ic_dhcp_init_options(b->exten);
742 	else
743 #endif
744 		ic_bootp_init_ext(b->exten);
745 
746 	/* Chain packet down the line... */
747 	skb->dev = dev;
748 	skb->protocol = htons(ETH_P_IP);
749 	if ((dev->hard_header &&
750 	     dev->hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) ||
751 	    dev_queue_xmit(skb) < 0)
752 		printk("E");
753 }
754 
755 
756 /*
757  *  Copy BOOTP-supplied string if not already set.
758  */
759 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
760 {
761 	if (!len)
762 		return 0;
763 	if (len > max-1)
764 		len = max-1;
765 	memcpy(dest, src, len);
766 	dest[len] = '\0';
767 	return 1;
768 }
769 
770 
771 /*
772  *  Process BOOTP extensions.
773  */
774 static void __init ic_do_bootp_ext(u8 *ext)
775 {
776        u8 servers;
777        int i;
778 
779 #ifdef IPCONFIG_DEBUG
780 	u8 *c;
781 
782 	printk("DHCP/BOOTP: Got extension %d:",*ext);
783 	for(c=ext+2; c<ext+2+ext[1]; c++)
784 		printk(" %02x", *c);
785 	printk("\n");
786 #endif
787 
788 	switch (*ext++) {
789 		case 1:		/* Subnet mask */
790 			if (ic_netmask == INADDR_NONE)
791 				memcpy(&ic_netmask, ext+1, 4);
792 			break;
793 		case 3:		/* Default gateway */
794 			if (ic_gateway == INADDR_NONE)
795 				memcpy(&ic_gateway, ext+1, 4);
796 			break;
797 		case 6:		/* DNS server */
798 			servers= *ext/4;
799 			if (servers > CONF_NAMESERVERS_MAX)
800 				servers = CONF_NAMESERVERS_MAX;
801 			for (i = 0; i < servers; i++) {
802 				if (ic_nameservers[i] == INADDR_NONE)
803 					memcpy(&ic_nameservers[i], ext+1+4*i, 4);
804 			}
805 			break;
806 		case 12:	/* Host name */
807 			ic_bootp_string(system_utsname.nodename, ext+1, *ext, __NEW_UTS_LEN);
808 			ic_host_name_set = 1;
809 			break;
810 		case 15:	/* Domain name (DNS) */
811 			ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
812 			break;
813 		case 17:	/* Root path */
814 			if (!root_server_path[0])
815 				ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
816 			break;
817 		case 40:	/* NIS Domain name (_not_ DNS) */
818 			ic_bootp_string(system_utsname.domainname, ext+1, *ext, __NEW_UTS_LEN);
819 			break;
820 	}
821 }
822 
823 
824 /*
825  *  Receive BOOTP reply.
826  */
827 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
828 {
829 	struct bootp_pkt *b;
830 	struct iphdr *h;
831 	struct ic_device *d;
832 	int len, ext_len;
833 
834 	/* Perform verifications before taking the lock.  */
835 	if (skb->pkt_type == PACKET_OTHERHOST)
836 		goto drop;
837 
838 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
839 		return NET_RX_DROP;
840 
841 	if (!pskb_may_pull(skb,
842 			   sizeof(struct iphdr) +
843 			   sizeof(struct udphdr)))
844 		goto drop;
845 
846 	b = (struct bootp_pkt *) skb->nh.iph;
847 	h = &b->iph;
848 
849 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
850 		goto drop;
851 
852 	/* Fragments are not supported */
853 	if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
854 		if (net_ratelimit())
855 			printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
856 			       "reply.\n");
857 		goto drop;
858 	}
859 
860 	if (skb->len < ntohs(h->tot_len))
861 		goto drop;
862 
863 	if (ip_fast_csum((char *) h, h->ihl))
864 		goto drop;
865 
866 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
867 		goto drop;
868 
869 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
870 		goto drop;
871 
872 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
873 	ext_len = len - (sizeof(*b) -
874 			 sizeof(struct iphdr) -
875 			 sizeof(struct udphdr) -
876 			 sizeof(b->exten));
877 	if (ext_len < 0)
878 		goto drop;
879 
880 	/* Ok the front looks good, make sure we can get at the rest.  */
881 	if (!pskb_may_pull(skb, skb->len))
882 		goto drop;
883 
884 	b = (struct bootp_pkt *) skb->nh.iph;
885 	h = &b->iph;
886 
887 	/* One reply at a time, please. */
888 	spin_lock(&ic_recv_lock);
889 
890 	/* If we already have a reply, just drop the packet */
891 	if (ic_got_reply)
892 		goto drop_unlock;
893 
894 	/* Find the ic_device that the packet arrived on */
895 	d = ic_first_dev;
896 	while (d && d->dev != dev)
897 		d = d->next;
898 	if (!d)
899 		goto drop_unlock;  /* should never happen */
900 
901 	/* Is it a reply to our BOOTP request? */
902 	if (b->op != BOOTP_REPLY ||
903 	    b->xid != d->xid) {
904 		if (net_ratelimit())
905 			printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
906 			       "op[%x] xid[%x]\n",
907 			       b->op, b->xid);
908 		goto drop_unlock;
909 	}
910 
911 	/* Parse extensions */
912 	if (ext_len >= 4 &&
913 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
914                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
915 		u8 *ext;
916 
917 #ifdef IPCONFIG_DHCP
918 		if (ic_proto_enabled & IC_USE_DHCP) {
919 			u32 server_id = INADDR_NONE;
920 			int mt = 0;
921 
922 			ext = &b->exten[4];
923 			while (ext < end && *ext != 0xff) {
924 				u8 *opt = ext++;
925 				if (*opt == 0)	/* Padding */
926 					continue;
927 				ext += *ext + 1;
928 				if (ext >= end)
929 					break;
930 				switch (*opt) {
931 				case 53:	/* Message type */
932 					if (opt[1])
933 						mt = opt[2];
934 					break;
935 				case 54:	/* Server ID (IP address) */
936 					if (opt[1] >= 4)
937 						memcpy(&server_id, opt + 2, 4);
938 					break;
939 				};
940 			}
941 
942 #ifdef IPCONFIG_DEBUG
943 			printk("DHCP: Got message type %d\n", mt);
944 #endif
945 
946 			switch (mt) {
947 			case DHCPOFFER:
948 				/* While in the process of accepting one offer,
949 				 * ignore all others.
950 				 */
951 				if (ic_myaddr != INADDR_NONE)
952 					goto drop_unlock;
953 
954 				/* Let's accept that offer. */
955 				ic_myaddr = b->your_ip;
956 				ic_servaddr = server_id;
957 #ifdef IPCONFIG_DEBUG
958 				printk("DHCP: Offered address %u.%u.%u.%u",
959 				       NIPQUAD(ic_myaddr));
960 				printk(" by server %u.%u.%u.%u\n",
961 				       NIPQUAD(ic_servaddr));
962 #endif
963 				/* The DHCP indicated server address takes
964 				 * precedence over the bootp header one if
965 				 * they are different.
966 				 */
967 				if ((server_id != INADDR_NONE) &&
968 				    (b->server_ip != server_id))
969 					b->server_ip = ic_servaddr;
970 				break;
971 
972 			case DHCPACK:
973 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
974 					goto drop_unlock;
975 
976 				/* Yeah! */
977 				break;
978 
979 			default:
980 				/* Urque.  Forget it*/
981 				ic_myaddr = INADDR_NONE;
982 				ic_servaddr = INADDR_NONE;
983 				goto drop_unlock;
984 			};
985 
986 			ic_dhcp_msgtype = mt;
987 
988 		}
989 #endif /* IPCONFIG_DHCP */
990 
991 		ext = &b->exten[4];
992 		while (ext < end && *ext != 0xff) {
993 			u8 *opt = ext++;
994 			if (*opt == 0)	/* Padding */
995 				continue;
996 			ext += *ext + 1;
997 			if (ext < end)
998 				ic_do_bootp_ext(opt);
999 		}
1000 	}
1001 
1002 	/* We have a winner! */
1003 	ic_dev = dev;
1004 	ic_myaddr = b->your_ip;
1005 	ic_servaddr = b->server_ip;
1006 	if (ic_gateway == INADDR_NONE && b->relay_ip)
1007 		ic_gateway = b->relay_ip;
1008 	if (ic_nameservers[0] == INADDR_NONE)
1009 		ic_nameservers[0] = ic_servaddr;
1010 	ic_got_reply = IC_BOOTP;
1011 
1012 drop_unlock:
1013 	/* Show's over.  Nothing to see here.  */
1014 	spin_unlock(&ic_recv_lock);
1015 
1016 drop:
1017 	/* Throw the packet out. */
1018 	kfree_skb(skb);
1019 
1020 	return 0;
1021 }
1022 
1023 
1024 #endif
1025 
1026 
1027 /*
1028  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1029  */
1030 
1031 #ifdef IPCONFIG_DYNAMIC
1032 
1033 static int __init ic_dynamic(void)
1034 {
1035 	int retries;
1036 	struct ic_device *d;
1037 	unsigned long start_jiffies, timeout, jiff;
1038 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1039 	int do_rarp = ic_proto_have_if & IC_RARP;
1040 
1041 	/*
1042 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1043 	 * This routine gets only called when some pieces of information
1044 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1045 	 */
1046 	if (!ic_proto_enabled) {
1047 		printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1048 		return -1;
1049 	}
1050 
1051 #ifdef IPCONFIG_BOOTP
1052 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1053 		printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1054 #endif
1055 #ifdef IPCONFIG_RARP
1056 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1057 		printk(KERN_ERR "RARP: No suitable device found.\n");
1058 #endif
1059 
1060 	if (!ic_proto_have_if)
1061 		/* Error message already printed */
1062 		return -1;
1063 
1064 	/*
1065 	 * Setup protocols
1066 	 */
1067 #ifdef IPCONFIG_BOOTP
1068 	if (do_bootp)
1069 		ic_bootp_init();
1070 #endif
1071 #ifdef IPCONFIG_RARP
1072 	if (do_rarp)
1073 		ic_rarp_init();
1074 #endif
1075 
1076 	/*
1077 	 * Send requests and wait, until we get an answer. This loop
1078 	 * seems to be a terrible waste of CPU time, but actually there is
1079 	 * only one process running at all, so we don't need to use any
1080 	 * scheduler functions.
1081 	 * [Actually we could now, but the nothing else running note still
1082 	 *  applies.. - AC]
1083 	 */
1084 	printk(KERN_NOTICE "Sending %s%s%s requests .",
1085 	       do_bootp
1086 		? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1087 	       (do_bootp && do_rarp) ? " and " : "",
1088 	       do_rarp ? "RARP" : "");
1089 
1090 	start_jiffies = jiffies;
1091 	d = ic_first_dev;
1092 	retries = CONF_SEND_RETRIES;
1093 	get_random_bytes(&timeout, sizeof(timeout));
1094 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1095 	for(;;) {
1096 #ifdef IPCONFIG_BOOTP
1097 		if (do_bootp && (d->able & IC_BOOTP))
1098 			ic_bootp_send_if(d, jiffies - start_jiffies);
1099 #endif
1100 #ifdef IPCONFIG_RARP
1101 		if (do_rarp && (d->able & IC_RARP))
1102 			ic_rarp_send_if(d);
1103 #endif
1104 
1105 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1106 		while (time_before(jiffies, jiff) && !ic_got_reply) {
1107 			set_current_state(TASK_UNINTERRUPTIBLE);
1108 			schedule_timeout(1);
1109 		}
1110 #ifdef IPCONFIG_DHCP
1111 		/* DHCP isn't done until we get a DHCPACK. */
1112 		if ((ic_got_reply & IC_BOOTP)
1113 		    && (ic_proto_enabled & IC_USE_DHCP)
1114 		    && ic_dhcp_msgtype != DHCPACK)
1115 		{
1116 			ic_got_reply = 0;
1117 			printk(",");
1118 			continue;
1119 		}
1120 #endif /* IPCONFIG_DHCP */
1121 
1122 		if (ic_got_reply) {
1123 			printk(" OK\n");
1124 			break;
1125 		}
1126 
1127 		if ((d = d->next))
1128 			continue;
1129 
1130 		if (! --retries) {
1131 			printk(" timed out!\n");
1132 			break;
1133 		}
1134 
1135 		d = ic_first_dev;
1136 
1137 		timeout = timeout CONF_TIMEOUT_MULT;
1138 		if (timeout > CONF_TIMEOUT_MAX)
1139 			timeout = CONF_TIMEOUT_MAX;
1140 
1141 		printk(".");
1142 	}
1143 
1144 #ifdef IPCONFIG_BOOTP
1145 	if (do_bootp)
1146 		ic_bootp_cleanup();
1147 #endif
1148 #ifdef IPCONFIG_RARP
1149 	if (do_rarp)
1150 		ic_rarp_cleanup();
1151 #endif
1152 
1153 	if (!ic_got_reply) {
1154 		ic_myaddr = INADDR_NONE;
1155 		return -1;
1156 	}
1157 
1158 	printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1159 		((ic_got_reply & IC_RARP) ? "RARP"
1160 		 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1161 		NIPQUAD(ic_servaddr));
1162 	printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1163 
1164 	return 0;
1165 }
1166 
1167 #endif /* IPCONFIG_DYNAMIC */
1168 
1169 #ifdef CONFIG_PROC_FS
1170 
1171 static int pnp_seq_show(struct seq_file *seq, void *v)
1172 {
1173 	int i;
1174 
1175 	if (ic_proto_used & IC_PROTO)
1176 		seq_printf(seq, "#PROTO: %s\n",
1177 			   (ic_proto_used & IC_RARP) ? "RARP"
1178 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1179 	else
1180 		seq_puts(seq, "#MANUAL\n");
1181 
1182 	if (ic_domain[0])
1183 		seq_printf(seq,
1184 			   "domain %s\n", ic_domain);
1185 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1186 		if (ic_nameservers[i] != INADDR_NONE)
1187 			seq_printf(seq,
1188 				   "nameserver %u.%u.%u.%u\n",
1189 				   NIPQUAD(ic_nameservers[i]));
1190 	}
1191 	if (ic_servaddr != INADDR_NONE)
1192 		seq_printf(seq,
1193 			   "bootserver %u.%u.%u.%u\n",
1194 			   NIPQUAD(ic_servaddr));
1195 	return 0;
1196 }
1197 
1198 static int pnp_seq_open(struct inode *indoe, struct file *file)
1199 {
1200 	return single_open(file, pnp_seq_show, NULL);
1201 }
1202 
1203 static struct file_operations pnp_seq_fops = {
1204 	.owner		= THIS_MODULE,
1205 	.open		= pnp_seq_open,
1206 	.read		= seq_read,
1207 	.llseek		= seq_lseek,
1208 	.release	= single_release,
1209 };
1210 #endif /* CONFIG_PROC_FS */
1211 
1212 /*
1213  *  Extract IP address from the parameter string if needed. Note that we
1214  *  need to have root_server_addr set _before_ IPConfig gets called as it
1215  *  can override it.
1216  */
1217 u32 __init root_nfs_parse_addr(char *name)
1218 {
1219 	u32 addr;
1220 	int octets = 0;
1221 	char *cp, *cq;
1222 
1223 	cp = cq = name;
1224 	while (octets < 4) {
1225 		while (*cp >= '0' && *cp <= '9')
1226 			cp++;
1227 		if (cp == cq || cp - cq > 3)
1228 			break;
1229 		if (*cp == '.' || octets == 3)
1230 			octets++;
1231 		if (octets < 4)
1232 			cp++;
1233 		cq = cp;
1234 	}
1235 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1236 		if (*cp == ':')
1237 			*cp++ = '\0';
1238 		addr = in_aton(name);
1239 		memmove(name, cp, strlen(cp) + 1);
1240 	} else
1241 		addr = INADDR_NONE;
1242 
1243 	return addr;
1244 }
1245 
1246 /*
1247  *	IP Autoconfig dispatcher.
1248  */
1249 
1250 static int __init ip_auto_config(void)
1251 {
1252 	u32 addr;
1253 
1254 #ifdef CONFIG_PROC_FS
1255 	proc_net_fops_create("pnp", S_IRUGO, &pnp_seq_fops);
1256 #endif /* CONFIG_PROC_FS */
1257 
1258 	if (!ic_enable)
1259 		return 0;
1260 
1261 	DBG(("IP-Config: Entered.\n"));
1262 #ifdef IPCONFIG_DYNAMIC
1263  try_try_again:
1264 #endif
1265 	/* Give hardware a chance to settle */
1266 	msleep(CONF_PRE_OPEN);
1267 
1268 	/* Setup all network devices */
1269 	if (ic_open_devs() < 0)
1270 		return -1;
1271 
1272 	/* Give drivers a chance to settle */
1273 	ssleep(CONF_POST_OPEN);
1274 
1275 	/*
1276 	 * If the config information is insufficient (e.g., our IP address or
1277 	 * IP address of the boot server is missing or we have multiple network
1278 	 * interfaces and no default was set), use BOOTP or RARP to get the
1279 	 * missing values.
1280 	 */
1281 	if (ic_myaddr == INADDR_NONE ||
1282 #ifdef CONFIG_ROOT_NFS
1283 	    (MAJOR(ROOT_DEV) == UNNAMED_MAJOR
1284 	     && root_server_addr == INADDR_NONE
1285 	     && ic_servaddr == INADDR_NONE) ||
1286 #endif
1287 	    ic_first_dev->next) {
1288 #ifdef IPCONFIG_DYNAMIC
1289 
1290 		int retries = CONF_OPEN_RETRIES;
1291 
1292 		if (ic_dynamic() < 0) {
1293 			ic_close_devs();
1294 
1295 			/*
1296 			 * I don't know why, but sometimes the
1297 			 * eepro100 driver (at least) gets upset and
1298 			 * doesn't work the first time it's opened.
1299 			 * But then if you close it and reopen it, it
1300 			 * works just fine.  So we need to try that at
1301 			 * least once before giving up.
1302 			 *
1303 			 * Also, if the root will be NFS-mounted, we
1304 			 * have nowhere to go if DHCP fails.  So we
1305 			 * just have to keep trying forever.
1306 			 *
1307 			 * 				-- Chip
1308 			 */
1309 #ifdef CONFIG_ROOT_NFS
1310 			if (ROOT_DEV ==  Root_NFS) {
1311 				printk(KERN_ERR
1312 					"IP-Config: Retrying forever (NFS root)...\n");
1313 				goto try_try_again;
1314 			}
1315 #endif
1316 
1317 			if (--retries) {
1318 				printk(KERN_ERR
1319 				       "IP-Config: Reopening network devices...\n");
1320 				goto try_try_again;
1321 			}
1322 
1323 			/* Oh, well.  At least we tried. */
1324 			printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1325 			return -1;
1326 		}
1327 #else /* !DYNAMIC */
1328 		printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1329 		ic_close_devs();
1330 		return -1;
1331 #endif /* IPCONFIG_DYNAMIC */
1332 	} else {
1333 		/* Device selected manually or only one device -> use it */
1334 		ic_dev = ic_first_dev->dev;
1335 	}
1336 
1337 	addr = root_nfs_parse_addr(root_server_path);
1338 	if (root_server_addr == INADDR_NONE)
1339 		root_server_addr = addr;
1340 
1341 	/*
1342 	 * Use defaults whereever applicable.
1343 	 */
1344 	if (ic_defaults() < 0)
1345 		return -1;
1346 
1347 	/*
1348 	 * Close all network devices except the device we've
1349 	 * autoconfigured and set up routes.
1350 	 */
1351 	ic_close_devs();
1352 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1353 		return -1;
1354 
1355 	/*
1356 	 * Record which protocol was actually used.
1357 	 */
1358 #ifdef IPCONFIG_DYNAMIC
1359 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1360 #endif
1361 
1362 #ifndef IPCONFIG_SILENT
1363 	/*
1364 	 * Clue in the operator.
1365 	 */
1366 	printk("IP-Config: Complete:");
1367 	printk("\n      device=%s", ic_dev->name);
1368 	printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1369 	printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1370 	printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1371 	printk(",\n     host=%s, domain=%s, nis-domain=%s",
1372 	       system_utsname.nodename, ic_domain, system_utsname.domainname);
1373 	printk(",\n     bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1374 	printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1375 	printk(", rootpath=%s", root_server_path);
1376 	printk("\n");
1377 #endif /* !SILENT */
1378 
1379 	return 0;
1380 }
1381 
1382 late_initcall(ip_auto_config);
1383 
1384 
1385 /*
1386  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1387  *  command line parameter. It consists of option fields separated by colons in
1388  *  the following order:
1389  *
1390  *  <client-ip>:<server-ip>:<gw-ip>:<netmask>:<host name>:<device>:<PROTO>
1391  *
1392  *  Any of the fields can be empty which means to use a default value:
1393  *	<client-ip>	- address given by BOOTP or RARP
1394  *	<server-ip>	- address of host returning BOOTP or RARP packet
1395  *	<gw-ip>		- none, or the address returned by BOOTP
1396  *	<netmask>	- automatically determined from <client-ip>, or the
1397  *			  one returned by BOOTP
1398  *	<host name>	- <client-ip> in ASCII notation, or the name returned
1399  *			  by BOOTP
1400  *	<device>	- use all available devices
1401  *	<PROTO>:
1402  *	   off|none	    - don't do autoconfig at all (DEFAULT)
1403  *	   on|any           - use any configured protocol
1404  *	   dhcp|bootp|rarp  - use only the specified protocol
1405  *	   both             - use both BOOTP and RARP (not DHCP)
1406  */
1407 static int __init ic_proto_name(char *name)
1408 {
1409 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1410 		return 1;
1411 	}
1412 #ifdef CONFIG_IP_PNP_DHCP
1413 	else if (!strcmp(name, "dhcp")) {
1414 		ic_proto_enabled &= ~IC_RARP;
1415 		return 1;
1416 	}
1417 #endif
1418 #ifdef CONFIG_IP_PNP_BOOTP
1419 	else if (!strcmp(name, "bootp")) {
1420 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1421 		return 1;
1422 	}
1423 #endif
1424 #ifdef CONFIG_IP_PNP_RARP
1425 	else if (!strcmp(name, "rarp")) {
1426 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1427 		return 1;
1428 	}
1429 #endif
1430 #ifdef IPCONFIG_DYNAMIC
1431 	else if (!strcmp(name, "both")) {
1432 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1433 		return 1;
1434 	}
1435 #endif
1436 	return 0;
1437 }
1438 
1439 static int __init ip_auto_config_setup(char *addrs)
1440 {
1441 	char *cp, *ip, *dp;
1442 	int num = 0;
1443 
1444 	ic_set_manually = 1;
1445 
1446 	ic_enable = (*addrs &&
1447 		(strcmp(addrs, "off") != 0) &&
1448 		(strcmp(addrs, "none") != 0));
1449 	if (!ic_enable)
1450 		return 1;
1451 
1452 	if (ic_proto_name(addrs))
1453 		return 1;
1454 
1455 	/* Parse the whole string */
1456 	ip = addrs;
1457 	while (ip && *ip) {
1458 		if ((cp = strchr(ip, ':')))
1459 			*cp++ = '\0';
1460 		if (strlen(ip) > 0) {
1461 			DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1462 			switch (num) {
1463 			case 0:
1464 				if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1465 					ic_myaddr = INADDR_NONE;
1466 				break;
1467 			case 1:
1468 				if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1469 					ic_servaddr = INADDR_NONE;
1470 				break;
1471 			case 2:
1472 				if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1473 					ic_gateway = INADDR_NONE;
1474 				break;
1475 			case 3:
1476 				if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1477 					ic_netmask = INADDR_NONE;
1478 				break;
1479 			case 4:
1480 				if ((dp = strchr(ip, '.'))) {
1481 					*dp++ = '\0';
1482 					strlcpy(system_utsname.domainname, dp,
1483 						sizeof(system_utsname.domainname));
1484 				}
1485 				strlcpy(system_utsname.nodename, ip,
1486 					sizeof(system_utsname.nodename));
1487 				ic_host_name_set = 1;
1488 				break;
1489 			case 5:
1490 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1491 				break;
1492 			case 6:
1493 				ic_proto_name(ip);
1494 				break;
1495 			}
1496 		}
1497 		ip = cp;
1498 		num++;
1499 	}
1500 
1501 	return 1;
1502 }
1503 
1504 static int __init nfsaddrs_config_setup(char *addrs)
1505 {
1506 	return ip_auto_config_setup(addrs);
1507 }
1508 
1509 __setup("ip=", ip_auto_config_setup);
1510 __setup("nfsaddrs=", nfsaddrs_config_setup);
1511