xref: /linux/net/ipv4/ipconfig.c (revision 6fa79bcaecdbb0eb417afbc7fb0a8fa204308b62)
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 __be32 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 			pr_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 				pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small",
227 					dev->name, dev->mtu);
228 			if (!(dev->flags & IFF_NOARP))
229 				able |= IC_RARP;
230 			able &= ic_proto_enabled;
231 			if (ic_proto_enabled && !able)
232 				continue;
233 			oflags = dev->flags;
234 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
235 				pr_err("IP-Config: Failed to open %s\n",
236 				       dev->name);
237 				continue;
238 			}
239 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
240 				rtnl_unlock();
241 				return -ENOMEM;
242 			}
243 			d->dev = dev;
244 			*last = d;
245 			last = &d->next;
246 			d->flags = oflags;
247 			d->able = able;
248 			if (able & IC_BOOTP)
249 				get_random_bytes(&d->xid, sizeof(__be32));
250 			else
251 				d->xid = 0;
252 			ic_proto_have_if |= able;
253 			DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
254 				dev->name, able, d->xid));
255 		}
256 	}
257 
258 	/* no point in waiting if we could not bring up at least one device */
259 	if (!ic_first_dev)
260 		goto have_carrier;
261 
262 	/* wait for a carrier on at least one device */
263 	start = jiffies;
264 	while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
265 		for_each_netdev(&init_net, dev)
266 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
267 				goto have_carrier;
268 
269 		msleep(1);
270 	}
271 have_carrier:
272 	rtnl_unlock();
273 
274 	*last = NULL;
275 
276 	if (!ic_first_dev) {
277 		if (user_dev_name[0])
278 			pr_err("IP-Config: Device `%s' not found\n",
279 			       user_dev_name);
280 		else
281 			pr_err("IP-Config: No network devices available\n");
282 		return -ENODEV;
283 	}
284 	return 0;
285 }
286 
287 static void __init ic_close_devs(void)
288 {
289 	struct ic_device *d, *next;
290 	struct net_device *dev;
291 
292 	rtnl_lock();
293 	next = ic_first_dev;
294 	while ((d = next)) {
295 		next = d->next;
296 		dev = d->dev;
297 		if (dev != ic_dev) {
298 			DBG(("IP-Config: Downing %s\n", dev->name));
299 			dev_change_flags(dev, d->flags);
300 		}
301 		kfree(d);
302 	}
303 	rtnl_unlock();
304 }
305 
306 /*
307  *	Interface to various network functions.
308  */
309 
310 static inline void
311 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
312 {
313 	sin->sin_family = AF_INET;
314 	sin->sin_addr.s_addr = addr;
315 	sin->sin_port = port;
316 }
317 
318 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
319 {
320 	int res;
321 
322 	mm_segment_t oldfs = get_fs();
323 	set_fs(get_ds());
324 	res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
325 	set_fs(oldfs);
326 	return res;
327 }
328 
329 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
330 {
331 	int res;
332 
333 	mm_segment_t oldfs = get_fs();
334 	set_fs(get_ds());
335 	res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
336 	set_fs(oldfs);
337 	return res;
338 }
339 
340 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
341 {
342 	int res;
343 
344 	mm_segment_t oldfs = get_fs();
345 	set_fs(get_ds());
346 	res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
347 	set_fs(oldfs);
348 	return res;
349 }
350 
351 /*
352  *	Set up interface addresses and routes.
353  */
354 
355 static int __init ic_setup_if(void)
356 {
357 	struct ifreq ir;
358 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
359 	int err;
360 
361 	memset(&ir, 0, sizeof(ir));
362 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
363 	set_sockaddr(sin, ic_myaddr, 0);
364 	if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
365 		pr_err("IP-Config: Unable to set interface address (%d)\n",
366 		       err);
367 		return -1;
368 	}
369 	set_sockaddr(sin, ic_netmask, 0);
370 	if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
371 		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
372 		       err);
373 		return -1;
374 	}
375 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
376 	if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
377 		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
378 		       err);
379 		return -1;
380 	}
381 	/* Handle the case where we need non-standard MTU on the boot link (a network
382 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
383 	 * out, we'll try to muddle along.
384 	 */
385 	if (ic_dev_mtu != 0) {
386 		strcpy(ir.ifr_name, ic_dev->name);
387 		ir.ifr_mtu = ic_dev_mtu;
388 		if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
389 			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
390 			       ic_dev_mtu, err);
391 	}
392 	return 0;
393 }
394 
395 static int __init ic_setup_routes(void)
396 {
397 	/* No need to setup device routes, only the default route... */
398 
399 	if (ic_gateway != NONE) {
400 		struct rtentry rm;
401 		int err;
402 
403 		memset(&rm, 0, sizeof(rm));
404 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
405 			pr_err("IP-Config: Gateway not on directly connected network\n");
406 			return -1;
407 		}
408 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
409 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
410 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
411 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
412 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
413 			pr_err("IP-Config: Cannot add default route (%d)\n",
414 			       err);
415 			return -1;
416 		}
417 	}
418 
419 	return 0;
420 }
421 
422 /*
423  *	Fill in default values for all missing parameters.
424  */
425 
426 static int __init ic_defaults(void)
427 {
428 	/*
429 	 *	At this point we have no userspace running so need not
430 	 *	claim locks on system_utsname
431 	 */
432 
433 	if (!ic_host_name_set)
434 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
435 
436 	if (root_server_addr == NONE)
437 		root_server_addr = ic_servaddr;
438 
439 	if (ic_netmask == NONE) {
440 		if (IN_CLASSA(ntohl(ic_myaddr)))
441 			ic_netmask = htonl(IN_CLASSA_NET);
442 		else if (IN_CLASSB(ntohl(ic_myaddr)))
443 			ic_netmask = htonl(IN_CLASSB_NET);
444 		else if (IN_CLASSC(ntohl(ic_myaddr)))
445 			ic_netmask = htonl(IN_CLASSC_NET);
446 		else {
447 			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
448 			       &ic_myaddr);
449 			return -1;
450 		}
451 		printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
452 	}
453 
454 	return 0;
455 }
456 
457 /*
458  *	RARP support.
459  */
460 
461 #ifdef IPCONFIG_RARP
462 
463 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
464 
465 static struct packet_type rarp_packet_type __initdata = {
466 	.type =	cpu_to_be16(ETH_P_RARP),
467 	.func =	ic_rarp_recv,
468 };
469 
470 static inline void __init ic_rarp_init(void)
471 {
472 	dev_add_pack(&rarp_packet_type);
473 }
474 
475 static inline void __init ic_rarp_cleanup(void)
476 {
477 	dev_remove_pack(&rarp_packet_type);
478 }
479 
480 /*
481  *  Process received RARP packet.
482  */
483 static int __init
484 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
485 {
486 	struct arphdr *rarp;
487 	unsigned char *rarp_ptr;
488 	__be32 sip, tip;
489 	unsigned char *sha, *tha;		/* s for "source", t for "target" */
490 	struct ic_device *d;
491 
492 	if (!net_eq(dev_net(dev), &init_net))
493 		goto drop;
494 
495 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
496 		return NET_RX_DROP;
497 
498 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
499 		goto drop;
500 
501 	/* Basic sanity checks can be done without the lock.  */
502 	rarp = (struct arphdr *)skb_transport_header(skb);
503 
504 	/* If this test doesn't pass, it's not IP, or we should
505 	 * ignore it anyway.
506 	 */
507 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
508 		goto drop;
509 
510 	/* If it's not a RARP reply, delete it. */
511 	if (rarp->ar_op != htons(ARPOP_RREPLY))
512 		goto drop;
513 
514 	/* If it's not Ethernet, delete it. */
515 	if (rarp->ar_pro != htons(ETH_P_IP))
516 		goto drop;
517 
518 	if (!pskb_may_pull(skb, arp_hdr_len(dev)))
519 		goto drop;
520 
521 	/* OK, it is all there and looks valid, process... */
522 	rarp = (struct arphdr *)skb_transport_header(skb);
523 	rarp_ptr = (unsigned char *) (rarp + 1);
524 
525 	/* One reply at a time, please. */
526 	spin_lock(&ic_recv_lock);
527 
528 	/* If we already have a reply, just drop the packet */
529 	if (ic_got_reply)
530 		goto drop_unlock;
531 
532 	/* Find the ic_device that the packet arrived on */
533 	d = ic_first_dev;
534 	while (d && d->dev != dev)
535 		d = d->next;
536 	if (!d)
537 		goto drop_unlock;	/* should never happen */
538 
539 	/* Extract variable-width fields */
540 	sha = rarp_ptr;
541 	rarp_ptr += dev->addr_len;
542 	memcpy(&sip, rarp_ptr, 4);
543 	rarp_ptr += 4;
544 	tha = rarp_ptr;
545 	rarp_ptr += dev->addr_len;
546 	memcpy(&tip, rarp_ptr, 4);
547 
548 	/* Discard packets which are not meant for us. */
549 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
550 		goto drop_unlock;
551 
552 	/* Discard packets which are not from specified server. */
553 	if (ic_servaddr != NONE && ic_servaddr != sip)
554 		goto drop_unlock;
555 
556 	/* We have a winner! */
557 	ic_dev = dev;
558 	if (ic_myaddr == NONE)
559 		ic_myaddr = tip;
560 	ic_servaddr = sip;
561 	ic_got_reply = IC_RARP;
562 
563 drop_unlock:
564 	/* Show's over.  Nothing to see here.  */
565 	spin_unlock(&ic_recv_lock);
566 
567 drop:
568 	/* Throw the packet out. */
569 	kfree_skb(skb);
570 	return 0;
571 }
572 
573 
574 /*
575  *  Send RARP request packet over a single interface.
576  */
577 static void __init ic_rarp_send_if(struct ic_device *d)
578 {
579 	struct net_device *dev = d->dev;
580 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
581 		 dev->dev_addr, dev->dev_addr);
582 }
583 #endif
584 
585 /*
586  *  Predefine Nameservers
587  */
588 static inline void __init ic_nameservers_predef(void)
589 {
590 	int i;
591 
592 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
593 		ic_nameservers[i] = NONE;
594 }
595 
596 /*
597  *	DHCP/BOOTP support.
598  */
599 
600 #ifdef IPCONFIG_BOOTP
601 
602 struct bootp_pkt {		/* BOOTP packet format */
603 	struct iphdr iph;	/* IP header */
604 	struct udphdr udph;	/* UDP header */
605 	u8 op;			/* 1=request, 2=reply */
606 	u8 htype;		/* HW address type */
607 	u8 hlen;		/* HW address length */
608 	u8 hops;		/* Used only by gateways */
609 	__be32 xid;		/* Transaction ID */
610 	__be16 secs;		/* Seconds since we started */
611 	__be16 flags;		/* Just what it says */
612 	__be32 client_ip;		/* Client's IP address if known */
613 	__be32 your_ip;		/* Assigned IP address */
614 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
615 	__be32 relay_ip;		/* IP address of BOOTP relay */
616 	u8 hw_addr[16];		/* Client's HW address */
617 	u8 serv_name[64];	/* Server host name */
618 	u8 boot_file[128];	/* Name of boot file */
619 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
620 };
621 
622 /* packet ops */
623 #define BOOTP_REQUEST	1
624 #define BOOTP_REPLY	2
625 
626 /* DHCP message types */
627 #define DHCPDISCOVER	1
628 #define DHCPOFFER	2
629 #define DHCPREQUEST	3
630 #define DHCPDECLINE	4
631 #define DHCPACK		5
632 #define DHCPNAK		6
633 #define DHCPRELEASE	7
634 #define DHCPINFORM	8
635 
636 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
637 
638 static struct packet_type bootp_packet_type __initdata = {
639 	.type =	cpu_to_be16(ETH_P_IP),
640 	.func =	ic_bootp_recv,
641 };
642 
643 
644 /*
645  *  Initialize DHCP/BOOTP extension fields in the request.
646  */
647 
648 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
649 
650 #ifdef IPCONFIG_DHCP
651 
652 static void __init
653 ic_dhcp_init_options(u8 *options)
654 {
655 	u8 mt = ((ic_servaddr == NONE)
656 		 ? DHCPDISCOVER : DHCPREQUEST);
657 	u8 *e = options;
658 	int len;
659 
660 #ifdef IPCONFIG_DEBUG
661 	printk("DHCP: Sending message type %d\n", mt);
662 #endif
663 
664 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
665 	e += 4;
666 
667 	*e++ = 53;		/* DHCP message type */
668 	*e++ = 1;
669 	*e++ = mt;
670 
671 	if (mt == DHCPREQUEST) {
672 		*e++ = 54;	/* Server ID (IP address) */
673 		*e++ = 4;
674 		memcpy(e, &ic_servaddr, 4);
675 		e += 4;
676 
677 		*e++ = 50;	/* Requested IP address */
678 		*e++ = 4;
679 		memcpy(e, &ic_myaddr, 4);
680 		e += 4;
681 	}
682 
683 	/* always? */
684 	{
685 		static const u8 ic_req_params[] = {
686 			1,	/* Subnet mask */
687 			3,	/* Default gateway */
688 			6,	/* DNS server */
689 			12,	/* Host name */
690 			15,	/* Domain name */
691 			17,	/* Boot path */
692 			26,	/* MTU */
693 			40,	/* NIS domain name */
694 		};
695 
696 		*e++ = 55;	/* Parameter request list */
697 		*e++ = sizeof(ic_req_params);
698 		memcpy(e, ic_req_params, sizeof(ic_req_params));
699 		e += sizeof(ic_req_params);
700 
701 		if (ic_host_name_set) {
702 			*e++ = 12;	/* host-name */
703 			len = strlen(utsname()->nodename);
704 			*e++ = len;
705 			memcpy(e, utsname()->nodename, len);
706 			e += len;
707 		}
708 		if (*vendor_class_identifier) {
709 			pr_info("DHCP: sending class identifier \"%s\"\n",
710 				vendor_class_identifier);
711 			*e++ = 60;	/* Class-identifier */
712 			len = strlen(vendor_class_identifier);
713 			*e++ = len;
714 			memcpy(e, vendor_class_identifier, len);
715 			e += len;
716 		}
717 	}
718 
719 	*e++ = 255;	/* End of the list */
720 }
721 
722 #endif /* IPCONFIG_DHCP */
723 
724 static void __init ic_bootp_init_ext(u8 *e)
725 {
726 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
727 	e += 4;
728 	*e++ = 1;		/* Subnet mask request */
729 	*e++ = 4;
730 	e += 4;
731 	*e++ = 3;		/* Default gateway request */
732 	*e++ = 4;
733 	e += 4;
734 	*e++ = 5;		/* Name server request */
735 	*e++ = 8;
736 	e += 8;
737 	*e++ = 12;		/* Host name request */
738 	*e++ = 32;
739 	e += 32;
740 	*e++ = 40;		/* NIS Domain name request */
741 	*e++ = 32;
742 	e += 32;
743 	*e++ = 17;		/* Boot path */
744 	*e++ = 40;
745 	e += 40;
746 
747 	*e++ = 57;		/* set extension buffer size for reply */
748 	*e++ = 2;
749 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
750 	*e++ = 150;
751 
752 	*e++ = 255;		/* End of the list */
753 }
754 
755 
756 /*
757  *  Initialize the DHCP/BOOTP mechanism.
758  */
759 static inline void __init ic_bootp_init(void)
760 {
761 	ic_nameservers_predef();
762 
763 	dev_add_pack(&bootp_packet_type);
764 }
765 
766 
767 /*
768  *  DHCP/BOOTP cleanup.
769  */
770 static inline void __init ic_bootp_cleanup(void)
771 {
772 	dev_remove_pack(&bootp_packet_type);
773 }
774 
775 
776 /*
777  *  Send DHCP/BOOTP request to single interface.
778  */
779 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
780 {
781 	struct net_device *dev = d->dev;
782 	struct sk_buff *skb;
783 	struct bootp_pkt *b;
784 	struct iphdr *h;
785 	int hlen = LL_RESERVED_SPACE(dev);
786 	int tlen = dev->needed_tailroom;
787 
788 	/* Allocate packet */
789 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
790 			GFP_KERNEL);
791 	if (!skb)
792 		return;
793 	skb_reserve(skb, hlen);
794 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
795 	memset(b, 0, sizeof(struct bootp_pkt));
796 
797 	/* Construct IP header */
798 	skb_reset_network_header(skb);
799 	h = ip_hdr(skb);
800 	h->version = 4;
801 	h->ihl = 5;
802 	h->tot_len = htons(sizeof(struct bootp_pkt));
803 	h->frag_off = htons(IP_DF);
804 	h->ttl = 64;
805 	h->protocol = IPPROTO_UDP;
806 	h->daddr = htonl(INADDR_BROADCAST);
807 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
808 
809 	/* Construct UDP header */
810 	b->udph.source = htons(68);
811 	b->udph.dest = htons(67);
812 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
813 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
814 
815 	/* Construct DHCP/BOOTP header */
816 	b->op = BOOTP_REQUEST;
817 	if (dev->type < 256) /* check for false types */
818 		b->htype = dev->type;
819 	else if (dev->type == ARPHRD_FDDI)
820 		b->htype = ARPHRD_ETHER;
821 	else {
822 		printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
823 		b->htype = dev->type; /* can cause undefined behavior */
824 	}
825 
826 	/* server_ip and your_ip address are both already zero per RFC2131 */
827 	b->hlen = dev->addr_len;
828 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
829 	b->secs = htons(jiffies_diff / HZ);
830 	b->xid = d->xid;
831 
832 	/* add DHCP options or BOOTP extensions */
833 #ifdef IPCONFIG_DHCP
834 	if (ic_proto_enabled & IC_USE_DHCP)
835 		ic_dhcp_init_options(b->exten);
836 	else
837 #endif
838 		ic_bootp_init_ext(b->exten);
839 
840 	/* Chain packet down the line... */
841 	skb->dev = dev;
842 	skb->protocol = htons(ETH_P_IP);
843 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
844 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
845 		kfree_skb(skb);
846 		printk("E");
847 		return;
848 	}
849 
850 	if (dev_queue_xmit(skb) < 0)
851 		printk("E");
852 }
853 
854 
855 /*
856  *  Copy BOOTP-supplied string if not already set.
857  */
858 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
859 {
860 	if (!len)
861 		return 0;
862 	if (len > max-1)
863 		len = max-1;
864 	memcpy(dest, src, len);
865 	dest[len] = '\0';
866 	return 1;
867 }
868 
869 
870 /*
871  *  Process BOOTP extensions.
872  */
873 static void __init ic_do_bootp_ext(u8 *ext)
874 {
875 	u8 servers;
876 	int i;
877 	__be16 mtu;
878 
879 #ifdef IPCONFIG_DEBUG
880 	u8 *c;
881 
882 	printk("DHCP/BOOTP: Got extension %d:",*ext);
883 	for (c=ext+2; c<ext+2+ext[1]; c++)
884 		printk(" %02x", *c);
885 	printk("\n");
886 #endif
887 
888 	switch (*ext++) {
889 	case 1:		/* Subnet mask */
890 		if (ic_netmask == NONE)
891 			memcpy(&ic_netmask, ext+1, 4);
892 		break;
893 	case 3:		/* Default gateway */
894 		if (ic_gateway == NONE)
895 			memcpy(&ic_gateway, ext+1, 4);
896 		break;
897 	case 6:		/* DNS server */
898 		servers= *ext/4;
899 		if (servers > CONF_NAMESERVERS_MAX)
900 			servers = CONF_NAMESERVERS_MAX;
901 		for (i = 0; i < servers; i++) {
902 			if (ic_nameservers[i] == NONE)
903 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
904 		}
905 		break;
906 	case 12:	/* Host name */
907 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
908 				__NEW_UTS_LEN);
909 		ic_host_name_set = 1;
910 		break;
911 	case 15:	/* Domain name (DNS) */
912 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
913 		break;
914 	case 17:	/* Root path */
915 		if (!root_server_path[0])
916 			ic_bootp_string(root_server_path, ext+1, *ext,
917 					sizeof(root_server_path));
918 		break;
919 	case 26:	/* Interface MTU */
920 		memcpy(&mtu, ext+1, sizeof(mtu));
921 		ic_dev_mtu = ntohs(mtu);
922 		break;
923 	case 40:	/* NIS Domain name (_not_ DNS) */
924 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
925 				__NEW_UTS_LEN);
926 		break;
927 	}
928 }
929 
930 
931 /*
932  *  Receive BOOTP reply.
933  */
934 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
935 {
936 	struct bootp_pkt *b;
937 	struct iphdr *h;
938 	struct ic_device *d;
939 	int len, ext_len;
940 
941 	if (!net_eq(dev_net(dev), &init_net))
942 		goto drop;
943 
944 	/* Perform verifications before taking the lock.  */
945 	if (skb->pkt_type == PACKET_OTHERHOST)
946 		goto drop;
947 
948 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
949 		return NET_RX_DROP;
950 
951 	if (!pskb_may_pull(skb,
952 			   sizeof(struct iphdr) +
953 			   sizeof(struct udphdr)))
954 		goto drop;
955 
956 	b = (struct bootp_pkt *)skb_network_header(skb);
957 	h = &b->iph;
958 
959 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
960 		goto drop;
961 
962 	/* Fragments are not supported */
963 	if (ip_is_fragment(h)) {
964 		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
965 		goto drop;
966 	}
967 
968 	if (skb->len < ntohs(h->tot_len))
969 		goto drop;
970 
971 	if (ip_fast_csum((char *) h, h->ihl))
972 		goto drop;
973 
974 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
975 		goto drop;
976 
977 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
978 		goto drop;
979 
980 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
981 	ext_len = len - (sizeof(*b) -
982 			 sizeof(struct iphdr) -
983 			 sizeof(struct udphdr) -
984 			 sizeof(b->exten));
985 	if (ext_len < 0)
986 		goto drop;
987 
988 	/* Ok the front looks good, make sure we can get at the rest.  */
989 	if (!pskb_may_pull(skb, skb->len))
990 		goto drop;
991 
992 	b = (struct bootp_pkt *)skb_network_header(skb);
993 	h = &b->iph;
994 
995 	/* One reply at a time, please. */
996 	spin_lock(&ic_recv_lock);
997 
998 	/* If we already have a reply, just drop the packet */
999 	if (ic_got_reply)
1000 		goto drop_unlock;
1001 
1002 	/* Find the ic_device that the packet arrived on */
1003 	d = ic_first_dev;
1004 	while (d && d->dev != dev)
1005 		d = d->next;
1006 	if (!d)
1007 		goto drop_unlock;  /* should never happen */
1008 
1009 	/* Is it a reply to our BOOTP request? */
1010 	if (b->op != BOOTP_REPLY ||
1011 	    b->xid != d->xid) {
1012 		net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1013 				    b->op, b->xid);
1014 		goto drop_unlock;
1015 	}
1016 
1017 	/* Is it a reply for the device we are configuring? */
1018 	if (b->xid != ic_dev_xid) {
1019 		net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1020 		goto drop_unlock;
1021 	}
1022 
1023 	/* Parse extensions */
1024 	if (ext_len >= 4 &&
1025 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1026 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1027 		u8 *ext;
1028 
1029 #ifdef IPCONFIG_DHCP
1030 		if (ic_proto_enabled & IC_USE_DHCP) {
1031 			__be32 server_id = NONE;
1032 			int mt = 0;
1033 
1034 			ext = &b->exten[4];
1035 			while (ext < end && *ext != 0xff) {
1036 				u8 *opt = ext++;
1037 				if (*opt == 0)	/* Padding */
1038 					continue;
1039 				ext += *ext + 1;
1040 				if (ext >= end)
1041 					break;
1042 				switch (*opt) {
1043 				case 53:	/* Message type */
1044 					if (opt[1])
1045 						mt = opt[2];
1046 					break;
1047 				case 54:	/* Server ID (IP address) */
1048 					if (opt[1] >= 4)
1049 						memcpy(&server_id, opt + 2, 4);
1050 					break;
1051 				}
1052 			}
1053 
1054 #ifdef IPCONFIG_DEBUG
1055 			printk("DHCP: Got message type %d\n", mt);
1056 #endif
1057 
1058 			switch (mt) {
1059 			case DHCPOFFER:
1060 				/* While in the process of accepting one offer,
1061 				 * ignore all others.
1062 				 */
1063 				if (ic_myaddr != NONE)
1064 					goto drop_unlock;
1065 
1066 				/* Let's accept that offer. */
1067 				ic_myaddr = b->your_ip;
1068 				ic_servaddr = server_id;
1069 #ifdef IPCONFIG_DEBUG
1070 				printk("DHCP: Offered address %pI4 by server %pI4\n",
1071 				       &ic_myaddr, &ic_servaddr);
1072 #endif
1073 				/* The DHCP indicated server address takes
1074 				 * precedence over the bootp header one if
1075 				 * they are different.
1076 				 */
1077 				if ((server_id != NONE) &&
1078 				    (b->server_ip != server_id))
1079 					b->server_ip = ic_servaddr;
1080 				break;
1081 
1082 			case DHCPACK:
1083 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1084 					goto drop_unlock;
1085 
1086 				/* Yeah! */
1087 				break;
1088 
1089 			default:
1090 				/* Urque.  Forget it*/
1091 				ic_myaddr = NONE;
1092 				ic_servaddr = NONE;
1093 				goto drop_unlock;
1094 			}
1095 
1096 			ic_dhcp_msgtype = mt;
1097 
1098 		}
1099 #endif /* IPCONFIG_DHCP */
1100 
1101 		ext = &b->exten[4];
1102 		while (ext < end && *ext != 0xff) {
1103 			u8 *opt = ext++;
1104 			if (*opt == 0)	/* Padding */
1105 				continue;
1106 			ext += *ext + 1;
1107 			if (ext < end)
1108 				ic_do_bootp_ext(opt);
1109 		}
1110 	}
1111 
1112 	/* We have a winner! */
1113 	ic_dev = dev;
1114 	ic_myaddr = b->your_ip;
1115 	ic_servaddr = b->server_ip;
1116 	if (ic_gateway == NONE && b->relay_ip)
1117 		ic_gateway = b->relay_ip;
1118 	if (ic_nameservers[0] == NONE)
1119 		ic_nameservers[0] = ic_servaddr;
1120 	ic_got_reply = IC_BOOTP;
1121 
1122 drop_unlock:
1123 	/* Show's over.  Nothing to see here.  */
1124 	spin_unlock(&ic_recv_lock);
1125 
1126 drop:
1127 	/* Throw the packet out. */
1128 	kfree_skb(skb);
1129 
1130 	return 0;
1131 }
1132 
1133 
1134 #endif
1135 
1136 
1137 /*
1138  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1139  */
1140 
1141 #ifdef IPCONFIG_DYNAMIC
1142 
1143 static int __init ic_dynamic(void)
1144 {
1145 	int retries;
1146 	struct ic_device *d;
1147 	unsigned long start_jiffies, timeout, jiff;
1148 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1149 	int do_rarp = ic_proto_have_if & IC_RARP;
1150 
1151 	/*
1152 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1153 	 * This routine gets only called when some pieces of information
1154 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1155 	 */
1156 	if (!ic_proto_enabled) {
1157 		pr_err("IP-Config: Incomplete network configuration information\n");
1158 		return -1;
1159 	}
1160 
1161 #ifdef IPCONFIG_BOOTP
1162 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1163 		pr_err("DHCP/BOOTP: No suitable device found\n");
1164 #endif
1165 #ifdef IPCONFIG_RARP
1166 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1167 		pr_err("RARP: No suitable device found\n");
1168 #endif
1169 
1170 	if (!ic_proto_have_if)
1171 		/* Error message already printed */
1172 		return -1;
1173 
1174 	/*
1175 	 * Setup protocols
1176 	 */
1177 #ifdef IPCONFIG_BOOTP
1178 	if (do_bootp)
1179 		ic_bootp_init();
1180 #endif
1181 #ifdef IPCONFIG_RARP
1182 	if (do_rarp)
1183 		ic_rarp_init();
1184 #endif
1185 
1186 	/*
1187 	 * Send requests and wait, until we get an answer. This loop
1188 	 * seems to be a terrible waste of CPU time, but actually there is
1189 	 * only one process running at all, so we don't need to use any
1190 	 * scheduler functions.
1191 	 * [Actually we could now, but the nothing else running note still
1192 	 *  applies.. - AC]
1193 	 */
1194 	pr_notice("Sending %s%s%s requests .",
1195 		  do_bootp
1196 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1197 		  (do_bootp && do_rarp) ? " and " : "",
1198 		  do_rarp ? "RARP" : "");
1199 
1200 	start_jiffies = jiffies;
1201 	d = ic_first_dev;
1202 	retries = CONF_SEND_RETRIES;
1203 	get_random_bytes(&timeout, sizeof(timeout));
1204 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1205 	for (;;) {
1206 		/* Track the device we are configuring */
1207 		ic_dev_xid = d->xid;
1208 
1209 #ifdef IPCONFIG_BOOTP
1210 		if (do_bootp && (d->able & IC_BOOTP))
1211 			ic_bootp_send_if(d, jiffies - start_jiffies);
1212 #endif
1213 #ifdef IPCONFIG_RARP
1214 		if (do_rarp && (d->able & IC_RARP))
1215 			ic_rarp_send_if(d);
1216 #endif
1217 
1218 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1219 		while (time_before(jiffies, jiff) && !ic_got_reply)
1220 			schedule_timeout_uninterruptible(1);
1221 #ifdef IPCONFIG_DHCP
1222 		/* DHCP isn't done until we get a DHCPACK. */
1223 		if ((ic_got_reply & IC_BOOTP) &&
1224 		    (ic_proto_enabled & IC_USE_DHCP) &&
1225 		    ic_dhcp_msgtype != DHCPACK) {
1226 			ic_got_reply = 0;
1227 			pr_cont(",");
1228 			continue;
1229 		}
1230 #endif /* IPCONFIG_DHCP */
1231 
1232 		if (ic_got_reply) {
1233 			pr_cont(" OK\n");
1234 			break;
1235 		}
1236 
1237 		if ((d = d->next))
1238 			continue;
1239 
1240 		if (! --retries) {
1241 			pr_cont(" timed out!\n");
1242 			break;
1243 		}
1244 
1245 		d = ic_first_dev;
1246 
1247 		timeout = timeout CONF_TIMEOUT_MULT;
1248 		if (timeout > CONF_TIMEOUT_MAX)
1249 			timeout = CONF_TIMEOUT_MAX;
1250 
1251 		pr_cont(".");
1252 	}
1253 
1254 #ifdef IPCONFIG_BOOTP
1255 	if (do_bootp)
1256 		ic_bootp_cleanup();
1257 #endif
1258 #ifdef IPCONFIG_RARP
1259 	if (do_rarp)
1260 		ic_rarp_cleanup();
1261 #endif
1262 
1263 	if (!ic_got_reply) {
1264 		ic_myaddr = NONE;
1265 		return -1;
1266 	}
1267 
1268 	printk("IP-Config: Got %s answer from %pI4, ",
1269 		((ic_got_reply & IC_RARP) ? "RARP"
1270 		 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1271 	       &ic_servaddr);
1272 	pr_cont("my address is %pI4\n", &ic_myaddr);
1273 
1274 	return 0;
1275 }
1276 
1277 #endif /* IPCONFIG_DYNAMIC */
1278 
1279 #ifdef CONFIG_PROC_FS
1280 
1281 static int pnp_seq_show(struct seq_file *seq, void *v)
1282 {
1283 	int i;
1284 
1285 	if (ic_proto_used & IC_PROTO)
1286 		seq_printf(seq, "#PROTO: %s\n",
1287 			   (ic_proto_used & IC_RARP) ? "RARP"
1288 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1289 	else
1290 		seq_puts(seq, "#MANUAL\n");
1291 
1292 	if (ic_domain[0])
1293 		seq_printf(seq,
1294 			   "domain %s\n", ic_domain);
1295 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1296 		if (ic_nameservers[i] != NONE)
1297 			seq_printf(seq, "nameserver %pI4\n",
1298 				   &ic_nameservers[i]);
1299 	}
1300 	if (ic_servaddr != NONE)
1301 		seq_printf(seq, "bootserver %pI4\n",
1302 			   &ic_servaddr);
1303 	return 0;
1304 }
1305 
1306 static int pnp_seq_open(struct inode *indoe, struct file *file)
1307 {
1308 	return single_open(file, pnp_seq_show, NULL);
1309 }
1310 
1311 static const struct file_operations pnp_seq_fops = {
1312 	.owner		= THIS_MODULE,
1313 	.open		= pnp_seq_open,
1314 	.read		= seq_read,
1315 	.llseek		= seq_lseek,
1316 	.release	= single_release,
1317 };
1318 #endif /* CONFIG_PROC_FS */
1319 
1320 /*
1321  *  Extract IP address from the parameter string if needed. Note that we
1322  *  need to have root_server_addr set _before_ IPConfig gets called as it
1323  *  can override it.
1324  */
1325 __be32 __init root_nfs_parse_addr(char *name)
1326 {
1327 	__be32 addr;
1328 	int octets = 0;
1329 	char *cp, *cq;
1330 
1331 	cp = cq = name;
1332 	while (octets < 4) {
1333 		while (*cp >= '0' && *cp <= '9')
1334 			cp++;
1335 		if (cp == cq || cp - cq > 3)
1336 			break;
1337 		if (*cp == '.' || octets == 3)
1338 			octets++;
1339 		if (octets < 4)
1340 			cp++;
1341 		cq = cp;
1342 	}
1343 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1344 		if (*cp == ':')
1345 			*cp++ = '\0';
1346 		addr = in_aton(name);
1347 		memmove(name, cp, strlen(cp) + 1);
1348 	} else
1349 		addr = NONE;
1350 
1351 	return addr;
1352 }
1353 
1354 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1355 
1356 static int __init wait_for_devices(void)
1357 {
1358 	int i;
1359 
1360 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1361 		struct net_device *dev;
1362 		int found = 0;
1363 
1364 		rtnl_lock();
1365 		for_each_netdev(&init_net, dev) {
1366 			if (ic_is_init_dev(dev)) {
1367 				found = 1;
1368 				break;
1369 			}
1370 		}
1371 		rtnl_unlock();
1372 		if (found)
1373 			return 0;
1374 		ssleep(1);
1375 	}
1376 	return -ENODEV;
1377 }
1378 
1379 /*
1380  *	IP Autoconfig dispatcher.
1381  */
1382 
1383 static int __init ip_auto_config(void)
1384 {
1385 	__be32 addr;
1386 #ifdef IPCONFIG_DYNAMIC
1387 	int retries = CONF_OPEN_RETRIES;
1388 #endif
1389 	int err;
1390 	unsigned int i;
1391 
1392 #ifdef CONFIG_PROC_FS
1393 	proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1394 #endif /* CONFIG_PROC_FS */
1395 
1396 	if (!ic_enable)
1397 		return 0;
1398 
1399 	DBG(("IP-Config: Entered.\n"));
1400 #ifdef IPCONFIG_DYNAMIC
1401  try_try_again:
1402 #endif
1403 	/* Wait for devices to appear */
1404 	err = wait_for_devices();
1405 	if (err)
1406 		return err;
1407 
1408 	/* Setup all network devices */
1409 	err = ic_open_devs();
1410 	if (err)
1411 		return err;
1412 
1413 	/* Give drivers a chance to settle */
1414 	msleep(CONF_POST_OPEN);
1415 
1416 	/*
1417 	 * If the config information is insufficient (e.g., our IP address or
1418 	 * IP address of the boot server is missing or we have multiple network
1419 	 * interfaces and no default was set), use BOOTP or RARP to get the
1420 	 * missing values.
1421 	 */
1422 	if (ic_myaddr == NONE ||
1423 #ifdef CONFIG_ROOT_NFS
1424 	    (root_server_addr == NONE &&
1425 	     ic_servaddr == NONE &&
1426 	     ROOT_DEV == Root_NFS) ||
1427 #endif
1428 	    ic_first_dev->next) {
1429 #ifdef IPCONFIG_DYNAMIC
1430 		if (ic_dynamic() < 0) {
1431 			ic_close_devs();
1432 
1433 			/*
1434 			 * I don't know why, but sometimes the
1435 			 * eepro100 driver (at least) gets upset and
1436 			 * doesn't work the first time it's opened.
1437 			 * But then if you close it and reopen it, it
1438 			 * works just fine.  So we need to try that at
1439 			 * least once before giving up.
1440 			 *
1441 			 * Also, if the root will be NFS-mounted, we
1442 			 * have nowhere to go if DHCP fails.  So we
1443 			 * just have to keep trying forever.
1444 			 *
1445 			 * 				-- Chip
1446 			 */
1447 #ifdef CONFIG_ROOT_NFS
1448 			if (ROOT_DEV ==  Root_NFS) {
1449 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1450 				goto try_try_again;
1451 			}
1452 #endif
1453 
1454 			if (--retries) {
1455 				pr_err("IP-Config: Reopening network devices...\n");
1456 				goto try_try_again;
1457 			}
1458 
1459 			/* Oh, well.  At least we tried. */
1460 			pr_err("IP-Config: Auto-configuration of network failed\n");
1461 			return -1;
1462 		}
1463 #else /* !DYNAMIC */
1464 		pr_err("IP-Config: Incomplete network configuration information\n");
1465 		ic_close_devs();
1466 		return -1;
1467 #endif /* IPCONFIG_DYNAMIC */
1468 	} else {
1469 		/* Device selected manually or only one device -> use it */
1470 		ic_dev = ic_first_dev->dev;
1471 	}
1472 
1473 	addr = root_nfs_parse_addr(root_server_path);
1474 	if (root_server_addr == NONE)
1475 		root_server_addr = addr;
1476 
1477 	/*
1478 	 * Use defaults wherever applicable.
1479 	 */
1480 	if (ic_defaults() < 0)
1481 		return -1;
1482 
1483 	/*
1484 	 * Close all network devices except the device we've
1485 	 * autoconfigured and set up routes.
1486 	 */
1487 	ic_close_devs();
1488 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1489 		return -1;
1490 
1491 	/*
1492 	 * Record which protocol was actually used.
1493 	 */
1494 #ifdef IPCONFIG_DYNAMIC
1495 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1496 #endif
1497 
1498 #ifndef IPCONFIG_SILENT
1499 	/*
1500 	 * Clue in the operator.
1501 	 */
1502 	pr_info("IP-Config: Complete:\n");
1503 	pr_info("     device=%s, addr=%pI4, mask=%pI4, gw=%pI4\n",
1504 		ic_dev->name, &ic_myaddr, &ic_netmask, &ic_gateway);
1505 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1506 		utsname()->nodename, ic_domain, utsname()->domainname);
1507 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1508 		&ic_servaddr, &root_server_addr, root_server_path);
1509 	if (ic_dev_mtu)
1510 		pr_cont(", mtu=%d", ic_dev_mtu);
1511 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1512 		if (ic_nameservers[i] != NONE) {
1513 			pr_info("     nameserver%u=%pI4",
1514 				i, &ic_nameservers[i]);
1515 			break;
1516 		}
1517 	for (i++; i < CONF_NAMESERVERS_MAX; i++)
1518 		if (ic_nameservers[i] != NONE)
1519 			pr_cont(", nameserver%u=%pI4\n", i, &ic_nameservers[i]);
1520 #endif /* !SILENT */
1521 
1522 	return 0;
1523 }
1524 
1525 late_initcall(ip_auto_config);
1526 
1527 
1528 /*
1529  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1530  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1531  */
1532 static int __init ic_proto_name(char *name)
1533 {
1534 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1535 		return 1;
1536 	}
1537 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1538 		return 0;
1539 	}
1540 #ifdef CONFIG_IP_PNP_DHCP
1541 	else if (!strcmp(name, "dhcp")) {
1542 		ic_proto_enabled &= ~IC_RARP;
1543 		return 1;
1544 	}
1545 #endif
1546 #ifdef CONFIG_IP_PNP_BOOTP
1547 	else if (!strcmp(name, "bootp")) {
1548 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1549 		return 1;
1550 	}
1551 #endif
1552 #ifdef CONFIG_IP_PNP_RARP
1553 	else if (!strcmp(name, "rarp")) {
1554 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1555 		return 1;
1556 	}
1557 #endif
1558 #ifdef IPCONFIG_DYNAMIC
1559 	else if (!strcmp(name, "both")) {
1560 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1561 		return 1;
1562 	}
1563 #endif
1564 	return 0;
1565 }
1566 
1567 static int __init ip_auto_config_setup(char *addrs)
1568 {
1569 	char *cp, *ip, *dp;
1570 	int num = 0;
1571 
1572 	ic_set_manually = 1;
1573 	ic_enable = 1;
1574 
1575 	/*
1576 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1577 	 * and skip the below static IP processing.
1578 	 */
1579 	if (ic_proto_name(addrs))
1580 		return 1;
1581 
1582 	/* If no static IP is given, turn off autoconfig and bail.  */
1583 	if (*addrs == 0 ||
1584 	    strcmp(addrs, "off") == 0 ||
1585 	    strcmp(addrs, "none") == 0) {
1586 		ic_enable = 0;
1587 		return 1;
1588 	}
1589 
1590 	ic_nameservers_predef();
1591 
1592 	/* Parse string for static IP assignment.  */
1593 	ip = addrs;
1594 	while (ip && *ip) {
1595 		if ((cp = strchr(ip, ':')))
1596 			*cp++ = '\0';
1597 		if (strlen(ip) > 0) {
1598 			DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1599 			switch (num) {
1600 			case 0:
1601 				if ((ic_myaddr = in_aton(ip)) == ANY)
1602 					ic_myaddr = NONE;
1603 				break;
1604 			case 1:
1605 				if ((ic_servaddr = in_aton(ip)) == ANY)
1606 					ic_servaddr = NONE;
1607 				break;
1608 			case 2:
1609 				if ((ic_gateway = in_aton(ip)) == ANY)
1610 					ic_gateway = NONE;
1611 				break;
1612 			case 3:
1613 				if ((ic_netmask = in_aton(ip)) == ANY)
1614 					ic_netmask = NONE;
1615 				break;
1616 			case 4:
1617 				if ((dp = strchr(ip, '.'))) {
1618 					*dp++ = '\0';
1619 					strlcpy(utsname()->domainname, dp,
1620 						sizeof(utsname()->domainname));
1621 				}
1622 				strlcpy(utsname()->nodename, ip,
1623 					sizeof(utsname()->nodename));
1624 				ic_host_name_set = 1;
1625 				break;
1626 			case 5:
1627 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1628 				break;
1629 			case 6:
1630 				if (ic_proto_name(ip) == 0 &&
1631 				    ic_myaddr == NONE) {
1632 					ic_enable = 0;
1633 				}
1634 				break;
1635 			case 7:
1636 				if (CONF_NAMESERVERS_MAX >= 1) {
1637 					ic_nameservers[0] = in_aton(ip);
1638 					if (ic_nameservers[0] == ANY)
1639 						ic_nameservers[0] = NONE;
1640 				}
1641 				break;
1642 			case 8:
1643 				if (CONF_NAMESERVERS_MAX >= 2) {
1644 					ic_nameservers[1] = in_aton(ip);
1645 					if (ic_nameservers[1] == ANY)
1646 						ic_nameservers[1] = NONE;
1647 				}
1648 				break;
1649 			}
1650 		}
1651 		ip = cp;
1652 		num++;
1653 	}
1654 
1655 	return 1;
1656 }
1657 __setup("ip=", ip_auto_config_setup);
1658 
1659 static int __init nfsaddrs_config_setup(char *addrs)
1660 {
1661 	return ip_auto_config_setup(addrs);
1662 }
1663 __setup("nfsaddrs=", nfsaddrs_config_setup);
1664 
1665 static int __init vendor_class_identifier_setup(char *addrs)
1666 {
1667 	if (strlcpy(vendor_class_identifier, addrs,
1668 		    sizeof(vendor_class_identifier))
1669 	    >= sizeof(vendor_class_identifier))
1670 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1671 			vendor_class_identifier);
1672 	return 1;
1673 }
1674 __setup("dhcpclass=", vendor_class_identifier_setup);
1675