xref: /linux/net/ipv4/ipconfig.c (revision eecb20720f1b29019725515051e41bc7c079f91f)
1 /*
2  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
3  *  user-supplied information to configure own IP address and routes.
4  *
5  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
6  *
7  *  Derived from network configuration code in fs/nfs/nfsroot.c,
8  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
9  *
10  *  BOOTP rewritten to construct and analyse packets itself instead
11  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
12  *					     -- MJ, December 1998
13  *
14  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
15  *  initialization scheme.
16  *	- Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
17  *
18  *  DHCP support added.  To users this looks like a whole separate
19  *  protocol, but we know it's just a bag on the side of BOOTP.
20  *		-- Chip Salzenberg <chip@valinux.com>, May 2000
21  *
22  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
23  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
24  *
25  *  Merged changes from 2.2.19 into 2.4.3
26  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
27  *
28  *  Multiple Nameservers in /proc/net/pnp
29  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
30  */
31 
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/kernel.h>
35 #include <linux/jiffies.h>
36 #include <linux/random.h>
37 #include <linux/init.h>
38 #include <linux/utsname.h>
39 #include <linux/in.h>
40 #include <linux/if.h>
41 #include <linux/inet.h>
42 #include <linux/inetdevice.h>
43 #include <linux/netdevice.h>
44 #include <linux/if_arp.h>
45 #include <linux/skbuff.h>
46 #include <linux/ip.h>
47 #include <linux/socket.h>
48 #include <linux/route.h>
49 #include <linux/udp.h>
50 #include <linux/proc_fs.h>
51 #include <linux/seq_file.h>
52 #include <linux/major.h>
53 #include <linux/root_dev.h>
54 #include <linux/delay.h>
55 #include <linux/nfs_fs.h>
56 #include <linux/slab.h>
57 #include <linux/export.h>
58 #include <net/net_namespace.h>
59 #include <net/arp.h>
60 #include <net/ip.h>
61 #include <net/ipconfig.h>
62 #include <net/route.h>
63 
64 #include <asm/uaccess.h>
65 #include <net/checksum.h>
66 #include <asm/processor.h>
67 
68 /* 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_POST_OPEN		10	/* After opening: 10 msecs */
92 #define CONF_CARRIER_TIMEOUT	120000	/* Wait for carrier timeout */
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 cpu_to_be32(INADDR_NONE)
106 #define ANY cpu_to_be32(INADDR_ANY)
107 
108 /*
109  * Public IP configuration
110  */
111 
112 /* This is used by platforms which might be able to set the ipconfig
113  * variables using firmware environment vars.  If this is set, it will
114  * ignore such firmware variables.
115  */
116 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
117 
118 static int ic_enable __initdata = 0;		/* IP config enabled? */
119 
120 /* Protocol choice */
121 int ic_proto_enabled __initdata = 0
122 #ifdef IPCONFIG_BOOTP
123 			| IC_BOOTP
124 #endif
125 #ifdef CONFIG_IP_PNP_DHCP
126 			| IC_USE_DHCP
127 #endif
128 #ifdef IPCONFIG_RARP
129 			| IC_RARP
130 #endif
131 			;
132 
133 static int ic_host_name_set __initdata = 0;	/* Host name set by us? */
134 
135 __be32 ic_myaddr = NONE;		/* My IP address */
136 static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
137 __be32 ic_gateway = NONE;	/* Gateway IP address */
138 
139 __be32 ic_servaddr = NONE;	/* Boot server IP address */
140 
141 __be32 root_server_addr = NONE;	/* Address of NFS server */
142 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
143 
144 u32 ic_dev_xid;		/* Device under configuration */
145 
146 /* vendor class identifier */
147 static char vendor_class_identifier[253] __initdata;
148 
149 /* Persistent data: */
150 
151 static int ic_proto_used;			/* Protocol used, if any */
152 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
153 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
154 
155 /*
156  * Private state.
157  */
158 
159 /* Name of user-selected boot device */
160 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
161 
162 /* Protocols supported by available interfaces */
163 static int ic_proto_have_if __initdata = 0;
164 
165 /* MTU for boot device */
166 static int ic_dev_mtu __initdata = 0;
167 
168 #ifdef IPCONFIG_DYNAMIC
169 static DEFINE_SPINLOCK(ic_recv_lock);
170 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
171 #endif
172 #ifdef IPCONFIG_DHCP
173 static int ic_dhcp_msgtype __initdata = 0;	/* DHCP msg type received */
174 #endif
175 
176 
177 /*
178  *	Network devices
179  */
180 
181 struct ic_device {
182 	struct ic_device *next;
183 	struct net_device *dev;
184 	unsigned short flags;
185 	short able;
186 	__be32 xid;
187 };
188 
189 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
190 static struct net_device *ic_dev __initdata = NULL;	/* Selected device */
191 
192 static bool __init ic_is_init_dev(struct net_device *dev)
193 {
194 	if (dev->flags & IFF_LOOPBACK)
195 		return false;
196 	return 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 }
201 
202 static int __init ic_open_devs(void)
203 {
204 	struct ic_device *d, **last;
205 	struct net_device *dev;
206 	unsigned short oflags;
207 	unsigned long start;
208 
209 	last = &ic_first_dev;
210 	rtnl_lock();
211 
212 	/* bring loopback device up first */
213 	for_each_netdev(&init_net, dev) {
214 		if (!(dev->flags & IFF_LOOPBACK))
215 			continue;
216 		if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
217 			printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
218 	}
219 
220 	for_each_netdev(&init_net, dev) {
221 		if (ic_is_init_dev(dev)) {
222 			int able = 0;
223 			if (dev->mtu >= 364)
224 				able |= IC_BOOTP;
225 			else
226 				printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
227 			if (!(dev->flags & IFF_NOARP))
228 				able |= IC_RARP;
229 			able &= ic_proto_enabled;
230 			if (ic_proto_enabled && !able)
231 				continue;
232 			oflags = dev->flags;
233 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
234 				printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
235 				continue;
236 			}
237 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
238 				rtnl_unlock();
239 				return -ENOMEM;
240 			}
241 			d->dev = dev;
242 			*last = d;
243 			last = &d->next;
244 			d->flags = oflags;
245 			d->able = able;
246 			if (able & IC_BOOTP)
247 				get_random_bytes(&d->xid, sizeof(__be32));
248 			else
249 				d->xid = 0;
250 			ic_proto_have_if |= able;
251 			DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
252 				dev->name, able, d->xid));
253 		}
254 	}
255 
256 	/* no point in waiting if we could not bring up at least one device */
257 	if (!ic_first_dev)
258 		goto have_carrier;
259 
260 	/* wait for a carrier on at least one device */
261 	start = jiffies;
262 	while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
263 		for_each_netdev(&init_net, dev)
264 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
265 				goto have_carrier;
266 
267 		msleep(1);
268 	}
269 have_carrier:
270 	rtnl_unlock();
271 
272 	*last = NULL;
273 
274 	if (!ic_first_dev) {
275 		if (user_dev_name[0])
276 			printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
277 		else
278 			printk(KERN_ERR "IP-Config: No network devices available.\n");
279 		return -ENODEV;
280 	}
281 	return 0;
282 }
283 
284 static void __init ic_close_devs(void)
285 {
286 	struct ic_device *d, *next;
287 	struct net_device *dev;
288 
289 	rtnl_lock();
290 	next = ic_first_dev;
291 	while ((d = next)) {
292 		next = d->next;
293 		dev = d->dev;
294 		if (dev != ic_dev) {
295 			DBG(("IP-Config: Downing %s\n", dev->name));
296 			dev_change_flags(dev, d->flags);
297 		}
298 		kfree(d);
299 	}
300 	rtnl_unlock();
301 }
302 
303 /*
304  *	Interface to various network functions.
305  */
306 
307 static inline void
308 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
309 {
310 	sin->sin_family = AF_INET;
311 	sin->sin_addr.s_addr = addr;
312 	sin->sin_port = port;
313 }
314 
315 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
316 {
317 	int res;
318 
319 	mm_segment_t oldfs = get_fs();
320 	set_fs(get_ds());
321 	res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
322 	set_fs(oldfs);
323 	return res;
324 }
325 
326 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
327 {
328 	int res;
329 
330 	mm_segment_t oldfs = get_fs();
331 	set_fs(get_ds());
332 	res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
333 	set_fs(oldfs);
334 	return res;
335 }
336 
337 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
338 {
339 	int res;
340 
341 	mm_segment_t oldfs = get_fs();
342 	set_fs(get_ds());
343 	res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
344 	set_fs(oldfs);
345 	return res;
346 }
347 
348 /*
349  *	Set up interface addresses and routes.
350  */
351 
352 static int __init ic_setup_if(void)
353 {
354 	struct ifreq ir;
355 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
356 	int err;
357 
358 	memset(&ir, 0, sizeof(ir));
359 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
360 	set_sockaddr(sin, ic_myaddr, 0);
361 	if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
362 		printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
363 		return -1;
364 	}
365 	set_sockaddr(sin, ic_netmask, 0);
366 	if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
367 		printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
368 		return -1;
369 	}
370 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
371 	if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
372 		printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
373 		return -1;
374 	}
375 	/* Handle the case where we need non-standard MTU on the boot link (a network
376 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
377 	 * out, we'll try to muddle along.
378 	 */
379 	if (ic_dev_mtu != 0) {
380 		strcpy(ir.ifr_name, ic_dev->name);
381 		ir.ifr_mtu = ic_dev_mtu;
382 		if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
383 			printk(KERN_ERR "IP-Config: Unable to set interface mtu to %d (%d).\n",
384 			                 ic_dev_mtu, err);
385 	}
386 	return 0;
387 }
388 
389 static int __init ic_setup_routes(void)
390 {
391 	/* No need to setup device routes, only the default route... */
392 
393 	if (ic_gateway != NONE) {
394 		struct rtentry rm;
395 		int err;
396 
397 		memset(&rm, 0, sizeof(rm));
398 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
399 			printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
400 			return -1;
401 		}
402 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
403 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
404 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
405 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
406 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
407 			printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
408 			return -1;
409 		}
410 	}
411 
412 	return 0;
413 }
414 
415 /*
416  *	Fill in default values for all missing parameters.
417  */
418 
419 static int __init ic_defaults(void)
420 {
421 	/*
422 	 *	At this point we have no userspace running so need not
423 	 *	claim locks on system_utsname
424 	 */
425 
426 	if (!ic_host_name_set)
427 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
428 
429 	if (root_server_addr == NONE)
430 		root_server_addr = ic_servaddr;
431 
432 	if (ic_netmask == NONE) {
433 		if (IN_CLASSA(ntohl(ic_myaddr)))
434 			ic_netmask = htonl(IN_CLASSA_NET);
435 		else if (IN_CLASSB(ntohl(ic_myaddr)))
436 			ic_netmask = htonl(IN_CLASSB_NET);
437 		else if (IN_CLASSC(ntohl(ic_myaddr)))
438 			ic_netmask = htonl(IN_CLASSC_NET);
439 		else {
440 			printk(KERN_ERR "IP-Config: Unable to guess netmask for address %pI4\n",
441 				&ic_myaddr);
442 			return -1;
443 		}
444 		printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
445 	}
446 
447 	return 0;
448 }
449 
450 /*
451  *	RARP support.
452  */
453 
454 #ifdef IPCONFIG_RARP
455 
456 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
457 
458 static struct packet_type rarp_packet_type __initdata = {
459 	.type =	cpu_to_be16(ETH_P_RARP),
460 	.func =	ic_rarp_recv,
461 };
462 
463 static inline void __init ic_rarp_init(void)
464 {
465 	dev_add_pack(&rarp_packet_type);
466 }
467 
468 static inline void __init ic_rarp_cleanup(void)
469 {
470 	dev_remove_pack(&rarp_packet_type);
471 }
472 
473 /*
474  *  Process received RARP packet.
475  */
476 static int __init
477 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
478 {
479 	struct arphdr *rarp;
480 	unsigned char *rarp_ptr;
481 	__be32 sip, tip;
482 	unsigned char *sha, *tha;		/* s for "source", t for "target" */
483 	struct ic_device *d;
484 
485 	if (!net_eq(dev_net(dev), &init_net))
486 		goto drop;
487 
488 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
489 		return NET_RX_DROP;
490 
491 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
492 		goto drop;
493 
494 	/* Basic sanity checks can be done without the lock.  */
495 	rarp = (struct arphdr *)skb_transport_header(skb);
496 
497 	/* If this test doesn't pass, it's not IP, or we should
498 	 * ignore it anyway.
499 	 */
500 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
501 		goto drop;
502 
503 	/* If it's not a RARP reply, delete it. */
504 	if (rarp->ar_op != htons(ARPOP_RREPLY))
505 		goto drop;
506 
507 	/* If it's not Ethernet, delete it. */
508 	if (rarp->ar_pro != htons(ETH_P_IP))
509 		goto drop;
510 
511 	if (!pskb_may_pull(skb, arp_hdr_len(dev)))
512 		goto drop;
513 
514 	/* OK, it is all there and looks valid, process... */
515 	rarp = (struct arphdr *)skb_transport_header(skb);
516 	rarp_ptr = (unsigned char *) (rarp + 1);
517 
518 	/* One reply at a time, please. */
519 	spin_lock(&ic_recv_lock);
520 
521 	/* If we already have a reply, just drop the packet */
522 	if (ic_got_reply)
523 		goto drop_unlock;
524 
525 	/* Find the ic_device that the packet arrived on */
526 	d = ic_first_dev;
527 	while (d && d->dev != dev)
528 		d = d->next;
529 	if (!d)
530 		goto drop_unlock;	/* should never happen */
531 
532 	/* Extract variable-width fields */
533 	sha = rarp_ptr;
534 	rarp_ptr += dev->addr_len;
535 	memcpy(&sip, rarp_ptr, 4);
536 	rarp_ptr += 4;
537 	tha = rarp_ptr;
538 	rarp_ptr += dev->addr_len;
539 	memcpy(&tip, rarp_ptr, 4);
540 
541 	/* Discard packets which are not meant for us. */
542 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
543 		goto drop_unlock;
544 
545 	/* Discard packets which are not from specified server. */
546 	if (ic_servaddr != NONE && ic_servaddr != sip)
547 		goto drop_unlock;
548 
549 	/* We have a winner! */
550 	ic_dev = dev;
551 	if (ic_myaddr == NONE)
552 		ic_myaddr = tip;
553 	ic_servaddr = sip;
554 	ic_got_reply = IC_RARP;
555 
556 drop_unlock:
557 	/* Show's over.  Nothing to see here.  */
558 	spin_unlock(&ic_recv_lock);
559 
560 drop:
561 	/* Throw the packet out. */
562 	kfree_skb(skb);
563 	return 0;
564 }
565 
566 
567 /*
568  *  Send RARP request packet over a single interface.
569  */
570 static void __init ic_rarp_send_if(struct ic_device *d)
571 {
572 	struct net_device *dev = d->dev;
573 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
574 		 dev->dev_addr, dev->dev_addr);
575 }
576 #endif
577 
578 /*
579  *	DHCP/BOOTP support.
580  */
581 
582 #ifdef IPCONFIG_BOOTP
583 
584 struct bootp_pkt {		/* BOOTP packet format */
585 	struct iphdr iph;	/* IP header */
586 	struct udphdr udph;	/* UDP header */
587 	u8 op;			/* 1=request, 2=reply */
588 	u8 htype;		/* HW address type */
589 	u8 hlen;		/* HW address length */
590 	u8 hops;		/* Used only by gateways */
591 	__be32 xid;		/* Transaction ID */
592 	__be16 secs;		/* Seconds since we started */
593 	__be16 flags;		/* Just what it says */
594 	__be32 client_ip;		/* Client's IP address if known */
595 	__be32 your_ip;		/* Assigned IP address */
596 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
597 	__be32 relay_ip;		/* IP address of BOOTP relay */
598 	u8 hw_addr[16];		/* Client's HW address */
599 	u8 serv_name[64];	/* Server host name */
600 	u8 boot_file[128];	/* Name of boot file */
601 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
602 };
603 
604 /* packet ops */
605 #define BOOTP_REQUEST	1
606 #define BOOTP_REPLY	2
607 
608 /* DHCP message types */
609 #define DHCPDISCOVER	1
610 #define DHCPOFFER	2
611 #define DHCPREQUEST	3
612 #define DHCPDECLINE	4
613 #define DHCPACK		5
614 #define DHCPNAK		6
615 #define DHCPRELEASE	7
616 #define DHCPINFORM	8
617 
618 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
619 
620 static struct packet_type bootp_packet_type __initdata = {
621 	.type =	cpu_to_be16(ETH_P_IP),
622 	.func =	ic_bootp_recv,
623 };
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)
636 {
637 	u8 mt = ((ic_servaddr == NONE)
638 		 ? DHCPDISCOVER : DHCPREQUEST);
639 	u8 *e = options;
640 	int len;
641 
642 #ifdef IPCONFIG_DEBUG
643 	printk("DHCP: Sending message type %d\n", mt);
644 #endif
645 
646 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
647 	e += 4;
648 
649 	*e++ = 53;		/* DHCP message type */
650 	*e++ = 1;
651 	*e++ = mt;
652 
653 	if (mt == DHCPREQUEST) {
654 		*e++ = 54;	/* Server ID (IP address) */
655 		*e++ = 4;
656 		memcpy(e, &ic_servaddr, 4);
657 		e += 4;
658 
659 		*e++ = 50;	/* Requested IP address */
660 		*e++ = 4;
661 		memcpy(e, &ic_myaddr, 4);
662 		e += 4;
663 	}
664 
665 	/* always? */
666 	{
667 		static const u8 ic_req_params[] = {
668 			1,	/* Subnet mask */
669 			3,	/* Default gateway */
670 			6,	/* DNS server */
671 			12,	/* Host name */
672 			15,	/* Domain name */
673 			17,	/* Boot path */
674 			26,	/* MTU */
675 			40,	/* NIS domain name */
676 		};
677 
678 		*e++ = 55;	/* Parameter request list */
679 		*e++ = sizeof(ic_req_params);
680 		memcpy(e, ic_req_params, sizeof(ic_req_params));
681 		e += sizeof(ic_req_params);
682 
683 		if (ic_host_name_set) {
684 			*e++ = 12;	/* host-name */
685 			len = strlen(utsname()->nodename);
686 			*e++ = len;
687 			memcpy(e, utsname()->nodename, len);
688 			e += len;
689 		}
690 		if (*vendor_class_identifier) {
691 			printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
692 			       vendor_class_identifier);
693 			*e++ = 60;	/* Class-identifier */
694 			len = strlen(vendor_class_identifier);
695 			*e++ = len;
696 			memcpy(e, vendor_class_identifier, len);
697 			e += len;
698 		}
699 	}
700 
701 	*e++ = 255;	/* End of the list */
702 }
703 
704 #endif /* IPCONFIG_DHCP */
705 
706 static void __init ic_bootp_init_ext(u8 *e)
707 {
708 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
709 	e += 4;
710 	*e++ = 1;		/* Subnet mask request */
711 	*e++ = 4;
712 	e += 4;
713 	*e++ = 3;		/* Default gateway request */
714 	*e++ = 4;
715 	e += 4;
716 	*e++ = 5;		/* Name server request */
717 	*e++ = 8;
718 	e += 8;
719 	*e++ = 12;		/* Host name request */
720 	*e++ = 32;
721 	e += 32;
722 	*e++ = 40;		/* NIS Domain name request */
723 	*e++ = 32;
724 	e += 32;
725 	*e++ = 17;		/* Boot path */
726 	*e++ = 40;
727 	e += 40;
728 
729 	*e++ = 57;		/* set extension buffer size for reply */
730 	*e++ = 2;
731 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
732 	*e++ = 150;
733 
734 	*e++ = 255;		/* End of the list */
735 }
736 
737 
738 /*
739  *  Initialize the DHCP/BOOTP mechanism.
740  */
741 static inline void __init ic_bootp_init(void)
742 {
743 	int i;
744 
745 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
746 		ic_nameservers[i] = NONE;
747 
748 	dev_add_pack(&bootp_packet_type);
749 }
750 
751 
752 /*
753  *  DHCP/BOOTP cleanup.
754  */
755 static inline void __init ic_bootp_cleanup(void)
756 {
757 	dev_remove_pack(&bootp_packet_type);
758 }
759 
760 
761 /*
762  *  Send DHCP/BOOTP request to single interface.
763  */
764 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
765 {
766 	struct net_device *dev = d->dev;
767 	struct sk_buff *skb;
768 	struct bootp_pkt *b;
769 	struct iphdr *h;
770 
771 	/* Allocate packet */
772 	skb = alloc_skb(sizeof(struct bootp_pkt) + LL_ALLOCATED_SPACE(dev) + 15,
773 			GFP_KERNEL);
774 	if (!skb)
775 		return;
776 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
777 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
778 	memset(b, 0, sizeof(struct bootp_pkt));
779 
780 	/* Construct IP header */
781 	skb_reset_network_header(skb);
782 	h = ip_hdr(skb);
783 	h->version = 4;
784 	h->ihl = 5;
785 	h->tot_len = htons(sizeof(struct bootp_pkt));
786 	h->frag_off = htons(IP_DF);
787 	h->ttl = 64;
788 	h->protocol = IPPROTO_UDP;
789 	h->daddr = htonl(INADDR_BROADCAST);
790 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
791 
792 	/* Construct UDP header */
793 	b->udph.source = htons(68);
794 	b->udph.dest = htons(67);
795 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
796 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
797 
798 	/* Construct DHCP/BOOTP header */
799 	b->op = BOOTP_REQUEST;
800 	if (dev->type < 256) /* check for false types */
801 		b->htype = dev->type;
802 	else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
803 		b->htype = ARPHRD_IEEE802;
804 	else if (dev->type == ARPHRD_FDDI)
805 		b->htype = ARPHRD_ETHER;
806 	else {
807 		printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
808 		b->htype = dev->type; /* can cause undefined behavior */
809 	}
810 
811 	/* server_ip and your_ip address are both already zero per RFC2131 */
812 	b->hlen = dev->addr_len;
813 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
814 	b->secs = htons(jiffies_diff / HZ);
815 	b->xid = d->xid;
816 
817 	/* add DHCP options or BOOTP extensions */
818 #ifdef IPCONFIG_DHCP
819 	if (ic_proto_enabled & IC_USE_DHCP)
820 		ic_dhcp_init_options(b->exten);
821 	else
822 #endif
823 		ic_bootp_init_ext(b->exten);
824 
825 	/* Chain packet down the line... */
826 	skb->dev = dev;
827 	skb->protocol = htons(ETH_P_IP);
828 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
829 			    dev->broadcast, dev->dev_addr, skb->len) < 0 ||
830 	    dev_queue_xmit(skb) < 0)
831 		printk("E");
832 }
833 
834 
835 /*
836  *  Copy BOOTP-supplied string if not already set.
837  */
838 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
839 {
840 	if (!len)
841 		return 0;
842 	if (len > max-1)
843 		len = max-1;
844 	memcpy(dest, src, len);
845 	dest[len] = '\0';
846 	return 1;
847 }
848 
849 
850 /*
851  *  Process BOOTP extensions.
852  */
853 static void __init ic_do_bootp_ext(u8 *ext)
854 {
855        u8 servers;
856        int i;
857 	u16 mtu;
858 
859 #ifdef IPCONFIG_DEBUG
860 	u8 *c;
861 
862 	printk("DHCP/BOOTP: Got extension %d:",*ext);
863 	for (c=ext+2; c<ext+2+ext[1]; c++)
864 		printk(" %02x", *c);
865 	printk("\n");
866 #endif
867 
868 	switch (*ext++) {
869 	case 1:		/* Subnet mask */
870 		if (ic_netmask == NONE)
871 			memcpy(&ic_netmask, ext+1, 4);
872 		break;
873 	case 3:		/* Default gateway */
874 		if (ic_gateway == NONE)
875 			memcpy(&ic_gateway, ext+1, 4);
876 		break;
877 	case 6:		/* DNS server */
878 		servers= *ext/4;
879 		if (servers > CONF_NAMESERVERS_MAX)
880 			servers = CONF_NAMESERVERS_MAX;
881 		for (i = 0; i < servers; i++) {
882 			if (ic_nameservers[i] == NONE)
883 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
884 		}
885 		break;
886 	case 12:	/* Host name */
887 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
888 				__NEW_UTS_LEN);
889 		ic_host_name_set = 1;
890 		break;
891 	case 15:	/* Domain name (DNS) */
892 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
893 		break;
894 	case 17:	/* Root path */
895 		if (!root_server_path[0])
896 			ic_bootp_string(root_server_path, ext+1, *ext,
897 					sizeof(root_server_path));
898 		break;
899 	case 26:	/* Interface MTU */
900 		memcpy(&mtu, ext+1, sizeof(mtu));
901 		ic_dev_mtu = ntohs(mtu);
902 		break;
903 	case 40:	/* NIS Domain name (_not_ DNS) */
904 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
905 				__NEW_UTS_LEN);
906 		break;
907 	}
908 }
909 
910 
911 /*
912  *  Receive BOOTP reply.
913  */
914 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
915 {
916 	struct bootp_pkt *b;
917 	struct iphdr *h;
918 	struct ic_device *d;
919 	int len, ext_len;
920 
921 	if (!net_eq(dev_net(dev), &init_net))
922 		goto drop;
923 
924 	/* Perform verifications before taking the lock.  */
925 	if (skb->pkt_type == PACKET_OTHERHOST)
926 		goto drop;
927 
928 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
929 		return NET_RX_DROP;
930 
931 	if (!pskb_may_pull(skb,
932 			   sizeof(struct iphdr) +
933 			   sizeof(struct udphdr)))
934 		goto drop;
935 
936 	b = (struct bootp_pkt *)skb_network_header(skb);
937 	h = &b->iph;
938 
939 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
940 		goto drop;
941 
942 	/* Fragments are not supported */
943 	if (ip_is_fragment(h)) {
944 		if (net_ratelimit())
945 			printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
946 			       "reply.\n");
947 		goto drop;
948 	}
949 
950 	if (skb->len < ntohs(h->tot_len))
951 		goto drop;
952 
953 	if (ip_fast_csum((char *) h, h->ihl))
954 		goto drop;
955 
956 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
957 		goto drop;
958 
959 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
960 		goto drop;
961 
962 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
963 	ext_len = len - (sizeof(*b) -
964 			 sizeof(struct iphdr) -
965 			 sizeof(struct udphdr) -
966 			 sizeof(b->exten));
967 	if (ext_len < 0)
968 		goto drop;
969 
970 	/* Ok the front looks good, make sure we can get at the rest.  */
971 	if (!pskb_may_pull(skb, skb->len))
972 		goto drop;
973 
974 	b = (struct bootp_pkt *)skb_network_header(skb);
975 	h = &b->iph;
976 
977 	/* One reply at a time, please. */
978 	spin_lock(&ic_recv_lock);
979 
980 	/* If we already have a reply, just drop the packet */
981 	if (ic_got_reply)
982 		goto drop_unlock;
983 
984 	/* Find the ic_device that the packet arrived on */
985 	d = ic_first_dev;
986 	while (d && d->dev != dev)
987 		d = d->next;
988 	if (!d)
989 		goto drop_unlock;  /* should never happen */
990 
991 	/* Is it a reply to our BOOTP request? */
992 	if (b->op != BOOTP_REPLY ||
993 	    b->xid != d->xid) {
994 		if (net_ratelimit())
995 			printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
996 			       "op[%x] xid[%x]\n",
997 			       b->op, b->xid);
998 		goto drop_unlock;
999 	}
1000 
1001 	/* Is it a reply for the device we are configuring? */
1002 	if (b->xid != ic_dev_xid) {
1003 		if (net_ratelimit())
1004 			printk(KERN_ERR "DHCP/BOOTP: Ignoring delayed packet\n");
1005 		goto drop_unlock;
1006 	}
1007 
1008 	/* Parse extensions */
1009 	if (ext_len >= 4 &&
1010 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1011 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1012 		u8 *ext;
1013 
1014 #ifdef IPCONFIG_DHCP
1015 		if (ic_proto_enabled & IC_USE_DHCP) {
1016 			__be32 server_id = NONE;
1017 			int mt = 0;
1018 
1019 			ext = &b->exten[4];
1020 			while (ext < end && *ext != 0xff) {
1021 				u8 *opt = ext++;
1022 				if (*opt == 0)	/* Padding */
1023 					continue;
1024 				ext += *ext + 1;
1025 				if (ext >= end)
1026 					break;
1027 				switch (*opt) {
1028 				case 53:	/* Message type */
1029 					if (opt[1])
1030 						mt = opt[2];
1031 					break;
1032 				case 54:	/* Server ID (IP address) */
1033 					if (opt[1] >= 4)
1034 						memcpy(&server_id, opt + 2, 4);
1035 					break;
1036 				}
1037 			}
1038 
1039 #ifdef IPCONFIG_DEBUG
1040 			printk("DHCP: Got message type %d\n", mt);
1041 #endif
1042 
1043 			switch (mt) {
1044 			case DHCPOFFER:
1045 				/* While in the process of accepting one offer,
1046 				 * ignore all others.
1047 				 */
1048 				if (ic_myaddr != NONE)
1049 					goto drop_unlock;
1050 
1051 				/* Let's accept that offer. */
1052 				ic_myaddr = b->your_ip;
1053 				ic_servaddr = server_id;
1054 #ifdef IPCONFIG_DEBUG
1055 				printk("DHCP: Offered address %pI4 by server %pI4\n",
1056 				       &ic_myaddr, &ic_servaddr);
1057 #endif
1058 				/* The DHCP indicated server address takes
1059 				 * precedence over the bootp header one if
1060 				 * they are different.
1061 				 */
1062 				if ((server_id != NONE) &&
1063 				    (b->server_ip != server_id))
1064 					b->server_ip = ic_servaddr;
1065 				break;
1066 
1067 			case DHCPACK:
1068 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1069 					goto drop_unlock;
1070 
1071 				/* Yeah! */
1072 				break;
1073 
1074 			default:
1075 				/* Urque.  Forget it*/
1076 				ic_myaddr = NONE;
1077 				ic_servaddr = NONE;
1078 				goto drop_unlock;
1079 			}
1080 
1081 			ic_dhcp_msgtype = mt;
1082 
1083 		}
1084 #endif /* IPCONFIG_DHCP */
1085 
1086 		ext = &b->exten[4];
1087 		while (ext < end && *ext != 0xff) {
1088 			u8 *opt = ext++;
1089 			if (*opt == 0)	/* Padding */
1090 				continue;
1091 			ext += *ext + 1;
1092 			if (ext < end)
1093 				ic_do_bootp_ext(opt);
1094 		}
1095 	}
1096 
1097 	/* We have a winner! */
1098 	ic_dev = dev;
1099 	ic_myaddr = b->your_ip;
1100 	ic_servaddr = b->server_ip;
1101 	if (ic_gateway == NONE && b->relay_ip)
1102 		ic_gateway = b->relay_ip;
1103 	if (ic_nameservers[0] == NONE)
1104 		ic_nameservers[0] = ic_servaddr;
1105 	ic_got_reply = IC_BOOTP;
1106 
1107 drop_unlock:
1108 	/* Show's over.  Nothing to see here.  */
1109 	spin_unlock(&ic_recv_lock);
1110 
1111 drop:
1112 	/* Throw the packet out. */
1113 	kfree_skb(skb);
1114 
1115 	return 0;
1116 }
1117 
1118 
1119 #endif
1120 
1121 
1122 /*
1123  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1124  */
1125 
1126 #ifdef IPCONFIG_DYNAMIC
1127 
1128 static int __init ic_dynamic(void)
1129 {
1130 	int retries;
1131 	struct ic_device *d;
1132 	unsigned long start_jiffies, timeout, jiff;
1133 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1134 	int do_rarp = ic_proto_have_if & IC_RARP;
1135 
1136 	/*
1137 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1138 	 * This routine gets only called when some pieces of information
1139 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1140 	 */
1141 	if (!ic_proto_enabled) {
1142 		printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1143 		return -1;
1144 	}
1145 
1146 #ifdef IPCONFIG_BOOTP
1147 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1148 		printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1149 #endif
1150 #ifdef IPCONFIG_RARP
1151 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1152 		printk(KERN_ERR "RARP: No suitable device found.\n");
1153 #endif
1154 
1155 	if (!ic_proto_have_if)
1156 		/* Error message already printed */
1157 		return -1;
1158 
1159 	/*
1160 	 * Setup protocols
1161 	 */
1162 #ifdef IPCONFIG_BOOTP
1163 	if (do_bootp)
1164 		ic_bootp_init();
1165 #endif
1166 #ifdef IPCONFIG_RARP
1167 	if (do_rarp)
1168 		ic_rarp_init();
1169 #endif
1170 
1171 	/*
1172 	 * Send requests and wait, until we get an answer. This loop
1173 	 * seems to be a terrible waste of CPU time, but actually there is
1174 	 * only one process running at all, so we don't need to use any
1175 	 * scheduler functions.
1176 	 * [Actually we could now, but the nothing else running note still
1177 	 *  applies.. - AC]
1178 	 */
1179 	printk(KERN_NOTICE "Sending %s%s%s requests .",
1180 	       do_bootp
1181 		? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1182 	       (do_bootp && do_rarp) ? " and " : "",
1183 	       do_rarp ? "RARP" : "");
1184 
1185 	start_jiffies = jiffies;
1186 	d = ic_first_dev;
1187 	retries = CONF_SEND_RETRIES;
1188 	get_random_bytes(&timeout, sizeof(timeout));
1189 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1190 	for (;;) {
1191 		/* Track the device we are configuring */
1192 		ic_dev_xid = d->xid;
1193 
1194 #ifdef IPCONFIG_BOOTP
1195 		if (do_bootp && (d->able & IC_BOOTP))
1196 			ic_bootp_send_if(d, jiffies - start_jiffies);
1197 #endif
1198 #ifdef IPCONFIG_RARP
1199 		if (do_rarp && (d->able & IC_RARP))
1200 			ic_rarp_send_if(d);
1201 #endif
1202 
1203 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1204 		while (time_before(jiffies, jiff) && !ic_got_reply)
1205 			schedule_timeout_uninterruptible(1);
1206 #ifdef IPCONFIG_DHCP
1207 		/* DHCP isn't done until we get a DHCPACK. */
1208 		if ((ic_got_reply & IC_BOOTP) &&
1209 		    (ic_proto_enabled & IC_USE_DHCP) &&
1210 		    ic_dhcp_msgtype != DHCPACK) {
1211 			ic_got_reply = 0;
1212 			printk(KERN_CONT ",");
1213 			continue;
1214 		}
1215 #endif /* IPCONFIG_DHCP */
1216 
1217 		if (ic_got_reply) {
1218 			printk(KERN_CONT " OK\n");
1219 			break;
1220 		}
1221 
1222 		if ((d = d->next))
1223 			continue;
1224 
1225 		if (! --retries) {
1226 			printk(KERN_CONT " timed out!\n");
1227 			break;
1228 		}
1229 
1230 		d = ic_first_dev;
1231 
1232 		timeout = timeout CONF_TIMEOUT_MULT;
1233 		if (timeout > CONF_TIMEOUT_MAX)
1234 			timeout = CONF_TIMEOUT_MAX;
1235 
1236 		printk(KERN_CONT ".");
1237 	}
1238 
1239 #ifdef IPCONFIG_BOOTP
1240 	if (do_bootp)
1241 		ic_bootp_cleanup();
1242 #endif
1243 #ifdef IPCONFIG_RARP
1244 	if (do_rarp)
1245 		ic_rarp_cleanup();
1246 #endif
1247 
1248 	if (!ic_got_reply) {
1249 		ic_myaddr = NONE;
1250 		return -1;
1251 	}
1252 
1253 	printk("IP-Config: Got %s answer from %pI4, ",
1254 		((ic_got_reply & IC_RARP) ? "RARP"
1255 		 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1256 		&ic_servaddr);
1257 	printk(KERN_CONT "my address is %pI4\n", &ic_myaddr);
1258 
1259 	return 0;
1260 }
1261 
1262 #endif /* IPCONFIG_DYNAMIC */
1263 
1264 #ifdef CONFIG_PROC_FS
1265 
1266 static int pnp_seq_show(struct seq_file *seq, void *v)
1267 {
1268 	int i;
1269 
1270 	if (ic_proto_used & IC_PROTO)
1271 		seq_printf(seq, "#PROTO: %s\n",
1272 			   (ic_proto_used & IC_RARP) ? "RARP"
1273 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1274 	else
1275 		seq_puts(seq, "#MANUAL\n");
1276 
1277 	if (ic_domain[0])
1278 		seq_printf(seq,
1279 			   "domain %s\n", ic_domain);
1280 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1281 		if (ic_nameservers[i] != NONE)
1282 			seq_printf(seq, "nameserver %pI4\n",
1283 				   &ic_nameservers[i]);
1284 	}
1285 	if (ic_servaddr != NONE)
1286 		seq_printf(seq, "bootserver %pI4\n",
1287 			   &ic_servaddr);
1288 	return 0;
1289 }
1290 
1291 static int pnp_seq_open(struct inode *indoe, struct file *file)
1292 {
1293 	return single_open(file, pnp_seq_show, NULL);
1294 }
1295 
1296 static const struct file_operations pnp_seq_fops = {
1297 	.owner		= THIS_MODULE,
1298 	.open		= pnp_seq_open,
1299 	.read		= seq_read,
1300 	.llseek		= seq_lseek,
1301 	.release	= single_release,
1302 };
1303 #endif /* CONFIG_PROC_FS */
1304 
1305 /*
1306  *  Extract IP address from the parameter string if needed. Note that we
1307  *  need to have root_server_addr set _before_ IPConfig gets called as it
1308  *  can override it.
1309  */
1310 __be32 __init root_nfs_parse_addr(char *name)
1311 {
1312 	__be32 addr;
1313 	int octets = 0;
1314 	char *cp, *cq;
1315 
1316 	cp = cq = name;
1317 	while (octets < 4) {
1318 		while (*cp >= '0' && *cp <= '9')
1319 			cp++;
1320 		if (cp == cq || cp - cq > 3)
1321 			break;
1322 		if (*cp == '.' || octets == 3)
1323 			octets++;
1324 		if (octets < 4)
1325 			cp++;
1326 		cq = cp;
1327 	}
1328 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1329 		if (*cp == ':')
1330 			*cp++ = '\0';
1331 		addr = in_aton(name);
1332 		memmove(name, cp, strlen(cp) + 1);
1333 	} else
1334 		addr = NONE;
1335 
1336 	return addr;
1337 }
1338 
1339 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1340 
1341 static int __init wait_for_devices(void)
1342 {
1343 	int i;
1344 
1345 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1346 		struct net_device *dev;
1347 		int found = 0;
1348 
1349 		rtnl_lock();
1350 		for_each_netdev(&init_net, dev) {
1351 			if (ic_is_init_dev(dev)) {
1352 				found = 1;
1353 				break;
1354 			}
1355 		}
1356 		rtnl_unlock();
1357 		if (found)
1358 			return 0;
1359 		ssleep(1);
1360 	}
1361 	return -ENODEV;
1362 }
1363 
1364 /*
1365  *	IP Autoconfig dispatcher.
1366  */
1367 
1368 static int __init ip_auto_config(void)
1369 {
1370 	__be32 addr;
1371 #ifdef IPCONFIG_DYNAMIC
1372 	int retries = CONF_OPEN_RETRIES;
1373 #endif
1374 	int err;
1375 
1376 #ifdef CONFIG_PROC_FS
1377 	proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1378 #endif /* CONFIG_PROC_FS */
1379 
1380 	if (!ic_enable)
1381 		return 0;
1382 
1383 	DBG(("IP-Config: Entered.\n"));
1384 #ifdef IPCONFIG_DYNAMIC
1385  try_try_again:
1386 #endif
1387 	/* Wait for devices to appear */
1388 	err = wait_for_devices();
1389 	if (err)
1390 		return err;
1391 
1392 	/* Setup all network devices */
1393 	err = ic_open_devs();
1394 	if (err)
1395 		return err;
1396 
1397 	/* Give drivers a chance to settle */
1398 	msleep(CONF_POST_OPEN);
1399 
1400 	/*
1401 	 * If the config information is insufficient (e.g., our IP address or
1402 	 * IP address of the boot server is missing or we have multiple network
1403 	 * interfaces and no default was set), use BOOTP or RARP to get the
1404 	 * missing values.
1405 	 */
1406 	if (ic_myaddr == NONE ||
1407 #ifdef CONFIG_ROOT_NFS
1408 	    (root_server_addr == NONE &&
1409 	     ic_servaddr == NONE &&
1410 	     ROOT_DEV == Root_NFS) ||
1411 #endif
1412 	    ic_first_dev->next) {
1413 #ifdef IPCONFIG_DYNAMIC
1414 		if (ic_dynamic() < 0) {
1415 			ic_close_devs();
1416 
1417 			/*
1418 			 * I don't know why, but sometimes the
1419 			 * eepro100 driver (at least) gets upset and
1420 			 * doesn't work the first time it's opened.
1421 			 * But then if you close it and reopen it, it
1422 			 * works just fine.  So we need to try that at
1423 			 * least once before giving up.
1424 			 *
1425 			 * Also, if the root will be NFS-mounted, we
1426 			 * have nowhere to go if DHCP fails.  So we
1427 			 * just have to keep trying forever.
1428 			 *
1429 			 * 				-- Chip
1430 			 */
1431 #ifdef CONFIG_ROOT_NFS
1432 			if (ROOT_DEV ==  Root_NFS) {
1433 				printk(KERN_ERR
1434 					"IP-Config: Retrying forever (NFS root)...\n");
1435 				goto try_try_again;
1436 			}
1437 #endif
1438 
1439 			if (--retries) {
1440 				printk(KERN_ERR
1441 				       "IP-Config: Reopening network devices...\n");
1442 				goto try_try_again;
1443 			}
1444 
1445 			/* Oh, well.  At least we tried. */
1446 			printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1447 			return -1;
1448 		}
1449 #else /* !DYNAMIC */
1450 		printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1451 		ic_close_devs();
1452 		return -1;
1453 #endif /* IPCONFIG_DYNAMIC */
1454 	} else {
1455 		/* Device selected manually or only one device -> use it */
1456 		ic_dev = ic_first_dev->dev;
1457 	}
1458 
1459 	addr = root_nfs_parse_addr(root_server_path);
1460 	if (root_server_addr == NONE)
1461 		root_server_addr = addr;
1462 
1463 	/*
1464 	 * Use defaults wherever applicable.
1465 	 */
1466 	if (ic_defaults() < 0)
1467 		return -1;
1468 
1469 	/*
1470 	 * Close all network devices except the device we've
1471 	 * autoconfigured and set up routes.
1472 	 */
1473 	ic_close_devs();
1474 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1475 		return -1;
1476 
1477 	/*
1478 	 * Record which protocol was actually used.
1479 	 */
1480 #ifdef IPCONFIG_DYNAMIC
1481 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1482 #endif
1483 
1484 #ifndef IPCONFIG_SILENT
1485 	/*
1486 	 * Clue in the operator.
1487 	 */
1488 	printk("IP-Config: Complete:\n");
1489 	printk("     device=%s", ic_dev->name);
1490 	printk(KERN_CONT ", addr=%pI4", &ic_myaddr);
1491 	printk(KERN_CONT ", mask=%pI4", &ic_netmask);
1492 	printk(KERN_CONT ", gw=%pI4", &ic_gateway);
1493 	printk(KERN_CONT ",\n     host=%s, domain=%s, nis-domain=%s",
1494 	       utsname()->nodename, ic_domain, utsname()->domainname);
1495 	printk(KERN_CONT ",\n     bootserver=%pI4", &ic_servaddr);
1496 	printk(KERN_CONT ", rootserver=%pI4", &root_server_addr);
1497 	printk(KERN_CONT ", rootpath=%s", root_server_path);
1498 	if (ic_dev_mtu)
1499 		printk(KERN_CONT ", mtu=%d", ic_dev_mtu);
1500 	printk(KERN_CONT "\n");
1501 #endif /* !SILENT */
1502 
1503 	return 0;
1504 }
1505 
1506 late_initcall(ip_auto_config);
1507 
1508 
1509 /*
1510  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1511  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1512  */
1513 static int __init ic_proto_name(char *name)
1514 {
1515 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1516 		return 1;
1517 	}
1518 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1519 		return 0;
1520 	}
1521 #ifdef CONFIG_IP_PNP_DHCP
1522 	else if (!strcmp(name, "dhcp")) {
1523 		ic_proto_enabled &= ~IC_RARP;
1524 		return 1;
1525 	}
1526 #endif
1527 #ifdef CONFIG_IP_PNP_BOOTP
1528 	else if (!strcmp(name, "bootp")) {
1529 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1530 		return 1;
1531 	}
1532 #endif
1533 #ifdef CONFIG_IP_PNP_RARP
1534 	else if (!strcmp(name, "rarp")) {
1535 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1536 		return 1;
1537 	}
1538 #endif
1539 #ifdef IPCONFIG_DYNAMIC
1540 	else if (!strcmp(name, "both")) {
1541 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1542 		return 1;
1543 	}
1544 #endif
1545 	return 0;
1546 }
1547 
1548 static int __init ip_auto_config_setup(char *addrs)
1549 {
1550 	char *cp, *ip, *dp;
1551 	int num = 0;
1552 
1553 	ic_set_manually = 1;
1554 	ic_enable = 1;
1555 
1556 	/*
1557 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1558 	 * and skip the below static IP processing.
1559 	 */
1560 	if (ic_proto_name(addrs))
1561 		return 1;
1562 
1563 	/* If no static IP is given, turn off autoconfig and bail.  */
1564 	if (*addrs == 0 ||
1565 	    strcmp(addrs, "off") == 0 ||
1566 	    strcmp(addrs, "none") == 0) {
1567 		ic_enable = 0;
1568 		return 1;
1569 	}
1570 
1571 	/* Parse string for static IP assignment.  */
1572 	ip = addrs;
1573 	while (ip && *ip) {
1574 		if ((cp = strchr(ip, ':')))
1575 			*cp++ = '\0';
1576 		if (strlen(ip) > 0) {
1577 			DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1578 			switch (num) {
1579 			case 0:
1580 				if ((ic_myaddr = in_aton(ip)) == ANY)
1581 					ic_myaddr = NONE;
1582 				break;
1583 			case 1:
1584 				if ((ic_servaddr = in_aton(ip)) == ANY)
1585 					ic_servaddr = NONE;
1586 				break;
1587 			case 2:
1588 				if ((ic_gateway = in_aton(ip)) == ANY)
1589 					ic_gateway = NONE;
1590 				break;
1591 			case 3:
1592 				if ((ic_netmask = in_aton(ip)) == ANY)
1593 					ic_netmask = NONE;
1594 				break;
1595 			case 4:
1596 				if ((dp = strchr(ip, '.'))) {
1597 					*dp++ = '\0';
1598 					strlcpy(utsname()->domainname, dp,
1599 						sizeof(utsname()->domainname));
1600 				}
1601 				strlcpy(utsname()->nodename, ip,
1602 					sizeof(utsname()->nodename));
1603 				ic_host_name_set = 1;
1604 				break;
1605 			case 5:
1606 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1607 				break;
1608 			case 6:
1609 				if (ic_proto_name(ip) == 0 &&
1610 				    ic_myaddr == NONE) {
1611 					ic_enable = 0;
1612 				}
1613 				break;
1614 			}
1615 		}
1616 		ip = cp;
1617 		num++;
1618 	}
1619 
1620 	return 1;
1621 }
1622 
1623 static int __init nfsaddrs_config_setup(char *addrs)
1624 {
1625 	return ip_auto_config_setup(addrs);
1626 }
1627 
1628 static int __init vendor_class_identifier_setup(char *addrs)
1629 {
1630 	if (strlcpy(vendor_class_identifier, addrs,
1631 		    sizeof(vendor_class_identifier))
1632 	    >= sizeof(vendor_class_identifier))
1633 		printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1634 		       vendor_class_identifier);
1635 	return 1;
1636 }
1637 
1638 __setup("ip=", ip_auto_config_setup);
1639 __setup("nfsaddrs=", nfsaddrs_config_setup);
1640 __setup("dhcpclass=", vendor_class_identifier_setup);
1641