xref: /openbmc/linux/net/ipv4/ipconfig.c (revision 08157984)
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  *	DHCP/BOOTP support.
587  */
588 
589 #ifdef IPCONFIG_BOOTP
590 
591 struct bootp_pkt {		/* BOOTP packet format */
592 	struct iphdr iph;	/* IP header */
593 	struct udphdr udph;	/* UDP header */
594 	u8 op;			/* 1=request, 2=reply */
595 	u8 htype;		/* HW address type */
596 	u8 hlen;		/* HW address length */
597 	u8 hops;		/* Used only by gateways */
598 	__be32 xid;		/* Transaction ID */
599 	__be16 secs;		/* Seconds since we started */
600 	__be16 flags;		/* Just what it says */
601 	__be32 client_ip;		/* Client's IP address if known */
602 	__be32 your_ip;		/* Assigned IP address */
603 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
604 	__be32 relay_ip;		/* IP address of BOOTP relay */
605 	u8 hw_addr[16];		/* Client's HW address */
606 	u8 serv_name[64];	/* Server host name */
607 	u8 boot_file[128];	/* Name of boot file */
608 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
609 };
610 
611 /* packet ops */
612 #define BOOTP_REQUEST	1
613 #define BOOTP_REPLY	2
614 
615 /* DHCP message types */
616 #define DHCPDISCOVER	1
617 #define DHCPOFFER	2
618 #define DHCPREQUEST	3
619 #define DHCPDECLINE	4
620 #define DHCPACK		5
621 #define DHCPNAK		6
622 #define DHCPRELEASE	7
623 #define DHCPINFORM	8
624 
625 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
626 
627 static struct packet_type bootp_packet_type __initdata = {
628 	.type =	cpu_to_be16(ETH_P_IP),
629 	.func =	ic_bootp_recv,
630 };
631 
632 
633 /*
634  *  Initialize DHCP/BOOTP extension fields in the request.
635  */
636 
637 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
638 
639 #ifdef IPCONFIG_DHCP
640 
641 static void __init
642 ic_dhcp_init_options(u8 *options)
643 {
644 	u8 mt = ((ic_servaddr == NONE)
645 		 ? DHCPDISCOVER : DHCPREQUEST);
646 	u8 *e = options;
647 	int len;
648 
649 #ifdef IPCONFIG_DEBUG
650 	printk("DHCP: Sending message type %d\n", mt);
651 #endif
652 
653 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
654 	e += 4;
655 
656 	*e++ = 53;		/* DHCP message type */
657 	*e++ = 1;
658 	*e++ = mt;
659 
660 	if (mt == DHCPREQUEST) {
661 		*e++ = 54;	/* Server ID (IP address) */
662 		*e++ = 4;
663 		memcpy(e, &ic_servaddr, 4);
664 		e += 4;
665 
666 		*e++ = 50;	/* Requested IP address */
667 		*e++ = 4;
668 		memcpy(e, &ic_myaddr, 4);
669 		e += 4;
670 	}
671 
672 	/* always? */
673 	{
674 		static const u8 ic_req_params[] = {
675 			1,	/* Subnet mask */
676 			3,	/* Default gateway */
677 			6,	/* DNS server */
678 			12,	/* Host name */
679 			15,	/* Domain name */
680 			17,	/* Boot path */
681 			26,	/* MTU */
682 			40,	/* NIS domain name */
683 		};
684 
685 		*e++ = 55;	/* Parameter request list */
686 		*e++ = sizeof(ic_req_params);
687 		memcpy(e, ic_req_params, sizeof(ic_req_params));
688 		e += sizeof(ic_req_params);
689 
690 		if (ic_host_name_set) {
691 			*e++ = 12;	/* host-name */
692 			len = strlen(utsname()->nodename);
693 			*e++ = len;
694 			memcpy(e, utsname()->nodename, len);
695 			e += len;
696 		}
697 		if (*vendor_class_identifier) {
698 			pr_info("DHCP: sending class identifier \"%s\"\n",
699 				vendor_class_identifier);
700 			*e++ = 60;	/* Class-identifier */
701 			len = strlen(vendor_class_identifier);
702 			*e++ = len;
703 			memcpy(e, vendor_class_identifier, len);
704 			e += len;
705 		}
706 	}
707 
708 	*e++ = 255;	/* End of the list */
709 }
710 
711 #endif /* IPCONFIG_DHCP */
712 
713 static void __init ic_bootp_init_ext(u8 *e)
714 {
715 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
716 	e += 4;
717 	*e++ = 1;		/* Subnet mask request */
718 	*e++ = 4;
719 	e += 4;
720 	*e++ = 3;		/* Default gateway request */
721 	*e++ = 4;
722 	e += 4;
723 	*e++ = 5;		/* Name server request */
724 	*e++ = 8;
725 	e += 8;
726 	*e++ = 12;		/* Host name request */
727 	*e++ = 32;
728 	e += 32;
729 	*e++ = 40;		/* NIS Domain name request */
730 	*e++ = 32;
731 	e += 32;
732 	*e++ = 17;		/* Boot path */
733 	*e++ = 40;
734 	e += 40;
735 
736 	*e++ = 57;		/* set extension buffer size for reply */
737 	*e++ = 2;
738 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
739 	*e++ = 150;
740 
741 	*e++ = 255;		/* End of the list */
742 }
743 
744 
745 /*
746  *  Initialize the DHCP/BOOTP mechanism.
747  */
748 static inline void __init ic_bootp_init(void)
749 {
750 	int i;
751 
752 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
753 		ic_nameservers[i] = NONE;
754 
755 	dev_add_pack(&bootp_packet_type);
756 }
757 
758 
759 /*
760  *  DHCP/BOOTP cleanup.
761  */
762 static inline void __init ic_bootp_cleanup(void)
763 {
764 	dev_remove_pack(&bootp_packet_type);
765 }
766 
767 
768 /*
769  *  Send DHCP/BOOTP request to single interface.
770  */
771 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
772 {
773 	struct net_device *dev = d->dev;
774 	struct sk_buff *skb;
775 	struct bootp_pkt *b;
776 	struct iphdr *h;
777 	int hlen = LL_RESERVED_SPACE(dev);
778 	int tlen = dev->needed_tailroom;
779 
780 	/* Allocate packet */
781 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
782 			GFP_KERNEL);
783 	if (!skb)
784 		return;
785 	skb_reserve(skb, hlen);
786 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
787 	memset(b, 0, sizeof(struct bootp_pkt));
788 
789 	/* Construct IP header */
790 	skb_reset_network_header(skb);
791 	h = ip_hdr(skb);
792 	h->version = 4;
793 	h->ihl = 5;
794 	h->tot_len = htons(sizeof(struct bootp_pkt));
795 	h->frag_off = htons(IP_DF);
796 	h->ttl = 64;
797 	h->protocol = IPPROTO_UDP;
798 	h->daddr = htonl(INADDR_BROADCAST);
799 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
800 
801 	/* Construct UDP header */
802 	b->udph.source = htons(68);
803 	b->udph.dest = htons(67);
804 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
805 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
806 
807 	/* Construct DHCP/BOOTP header */
808 	b->op = BOOTP_REQUEST;
809 	if (dev->type < 256) /* check for false types */
810 		b->htype = dev->type;
811 	else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
812 		b->htype = ARPHRD_IEEE802;
813 	else if (dev->type == ARPHRD_FDDI)
814 		b->htype = ARPHRD_ETHER;
815 	else {
816 		printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
817 		b->htype = dev->type; /* can cause undefined behavior */
818 	}
819 
820 	/* server_ip and your_ip address are both already zero per RFC2131 */
821 	b->hlen = dev->addr_len;
822 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
823 	b->secs = htons(jiffies_diff / HZ);
824 	b->xid = d->xid;
825 
826 	/* add DHCP options or BOOTP extensions */
827 #ifdef IPCONFIG_DHCP
828 	if (ic_proto_enabled & IC_USE_DHCP)
829 		ic_dhcp_init_options(b->exten);
830 	else
831 #endif
832 		ic_bootp_init_ext(b->exten);
833 
834 	/* Chain packet down the line... */
835 	skb->dev = dev;
836 	skb->protocol = htons(ETH_P_IP);
837 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
838 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
839 		kfree_skb(skb);
840 		printk("E");
841 		return;
842 	}
843 
844 	if (dev_queue_xmit(skb) < 0)
845 		printk("E");
846 }
847 
848 
849 /*
850  *  Copy BOOTP-supplied string if not already set.
851  */
852 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
853 {
854 	if (!len)
855 		return 0;
856 	if (len > max-1)
857 		len = max-1;
858 	memcpy(dest, src, len);
859 	dest[len] = '\0';
860 	return 1;
861 }
862 
863 
864 /*
865  *  Process BOOTP extensions.
866  */
867 static void __init ic_do_bootp_ext(u8 *ext)
868 {
869 	u8 servers;
870 	int i;
871 	__be16 mtu;
872 
873 #ifdef IPCONFIG_DEBUG
874 	u8 *c;
875 
876 	printk("DHCP/BOOTP: Got extension %d:",*ext);
877 	for (c=ext+2; c<ext+2+ext[1]; c++)
878 		printk(" %02x", *c);
879 	printk("\n");
880 #endif
881 
882 	switch (*ext++) {
883 	case 1:		/* Subnet mask */
884 		if (ic_netmask == NONE)
885 			memcpy(&ic_netmask, ext+1, 4);
886 		break;
887 	case 3:		/* Default gateway */
888 		if (ic_gateway == NONE)
889 			memcpy(&ic_gateway, ext+1, 4);
890 		break;
891 	case 6:		/* DNS server */
892 		servers= *ext/4;
893 		if (servers > CONF_NAMESERVERS_MAX)
894 			servers = CONF_NAMESERVERS_MAX;
895 		for (i = 0; i < servers; i++) {
896 			if (ic_nameservers[i] == NONE)
897 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
898 		}
899 		break;
900 	case 12:	/* Host name */
901 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
902 				__NEW_UTS_LEN);
903 		ic_host_name_set = 1;
904 		break;
905 	case 15:	/* Domain name (DNS) */
906 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
907 		break;
908 	case 17:	/* Root path */
909 		if (!root_server_path[0])
910 			ic_bootp_string(root_server_path, ext+1, *ext,
911 					sizeof(root_server_path));
912 		break;
913 	case 26:	/* Interface MTU */
914 		memcpy(&mtu, ext+1, sizeof(mtu));
915 		ic_dev_mtu = ntohs(mtu);
916 		break;
917 	case 40:	/* NIS Domain name (_not_ DNS) */
918 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
919 				__NEW_UTS_LEN);
920 		break;
921 	}
922 }
923 
924 
925 /*
926  *  Receive BOOTP reply.
927  */
928 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
929 {
930 	struct bootp_pkt *b;
931 	struct iphdr *h;
932 	struct ic_device *d;
933 	int len, ext_len;
934 
935 	if (!net_eq(dev_net(dev), &init_net))
936 		goto drop;
937 
938 	/* Perform verifications before taking the lock.  */
939 	if (skb->pkt_type == PACKET_OTHERHOST)
940 		goto drop;
941 
942 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
943 		return NET_RX_DROP;
944 
945 	if (!pskb_may_pull(skb,
946 			   sizeof(struct iphdr) +
947 			   sizeof(struct udphdr)))
948 		goto drop;
949 
950 	b = (struct bootp_pkt *)skb_network_header(skb);
951 	h = &b->iph;
952 
953 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
954 		goto drop;
955 
956 	/* Fragments are not supported */
957 	if (ip_is_fragment(h)) {
958 		if (net_ratelimit())
959 			pr_err("DHCP/BOOTP: Ignoring fragmented reply\n");
960 		goto drop;
961 	}
962 
963 	if (skb->len < ntohs(h->tot_len))
964 		goto drop;
965 
966 	if (ip_fast_csum((char *) h, h->ihl))
967 		goto drop;
968 
969 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
970 		goto drop;
971 
972 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
973 		goto drop;
974 
975 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
976 	ext_len = len - (sizeof(*b) -
977 			 sizeof(struct iphdr) -
978 			 sizeof(struct udphdr) -
979 			 sizeof(b->exten));
980 	if (ext_len < 0)
981 		goto drop;
982 
983 	/* Ok the front looks good, make sure we can get at the rest.  */
984 	if (!pskb_may_pull(skb, skb->len))
985 		goto drop;
986 
987 	b = (struct bootp_pkt *)skb_network_header(skb);
988 	h = &b->iph;
989 
990 	/* One reply at a time, please. */
991 	spin_lock(&ic_recv_lock);
992 
993 	/* If we already have a reply, just drop the packet */
994 	if (ic_got_reply)
995 		goto drop_unlock;
996 
997 	/* Find the ic_device that the packet arrived on */
998 	d = ic_first_dev;
999 	while (d && d->dev != dev)
1000 		d = d->next;
1001 	if (!d)
1002 		goto drop_unlock;  /* should never happen */
1003 
1004 	/* Is it a reply to our BOOTP request? */
1005 	if (b->op != BOOTP_REPLY ||
1006 	    b->xid != d->xid) {
1007 		if (net_ratelimit())
1008 			pr_err("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1009 			       b->op, b->xid);
1010 		goto drop_unlock;
1011 	}
1012 
1013 	/* Is it a reply for the device we are configuring? */
1014 	if (b->xid != ic_dev_xid) {
1015 		if (net_ratelimit())
1016 			pr_err("DHCP/BOOTP: Ignoring delayed packet\n");
1017 		goto drop_unlock;
1018 	}
1019 
1020 	/* Parse extensions */
1021 	if (ext_len >= 4 &&
1022 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1023 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1024 		u8 *ext;
1025 
1026 #ifdef IPCONFIG_DHCP
1027 		if (ic_proto_enabled & IC_USE_DHCP) {
1028 			__be32 server_id = NONE;
1029 			int mt = 0;
1030 
1031 			ext = &b->exten[4];
1032 			while (ext < end && *ext != 0xff) {
1033 				u8 *opt = ext++;
1034 				if (*opt == 0)	/* Padding */
1035 					continue;
1036 				ext += *ext + 1;
1037 				if (ext >= end)
1038 					break;
1039 				switch (*opt) {
1040 				case 53:	/* Message type */
1041 					if (opt[1])
1042 						mt = opt[2];
1043 					break;
1044 				case 54:	/* Server ID (IP address) */
1045 					if (opt[1] >= 4)
1046 						memcpy(&server_id, opt + 2, 4);
1047 					break;
1048 				}
1049 			}
1050 
1051 #ifdef IPCONFIG_DEBUG
1052 			printk("DHCP: Got message type %d\n", mt);
1053 #endif
1054 
1055 			switch (mt) {
1056 			case DHCPOFFER:
1057 				/* While in the process of accepting one offer,
1058 				 * ignore all others.
1059 				 */
1060 				if (ic_myaddr != NONE)
1061 					goto drop_unlock;
1062 
1063 				/* Let's accept that offer. */
1064 				ic_myaddr = b->your_ip;
1065 				ic_servaddr = server_id;
1066 #ifdef IPCONFIG_DEBUG
1067 				printk("DHCP: Offered address %pI4 by server %pI4\n",
1068 				       &ic_myaddr, &ic_servaddr);
1069 #endif
1070 				/* The DHCP indicated server address takes
1071 				 * precedence over the bootp header one if
1072 				 * they are different.
1073 				 */
1074 				if ((server_id != NONE) &&
1075 				    (b->server_ip != server_id))
1076 					b->server_ip = ic_servaddr;
1077 				break;
1078 
1079 			case DHCPACK:
1080 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1081 					goto drop_unlock;
1082 
1083 				/* Yeah! */
1084 				break;
1085 
1086 			default:
1087 				/* Urque.  Forget it*/
1088 				ic_myaddr = NONE;
1089 				ic_servaddr = NONE;
1090 				goto drop_unlock;
1091 			}
1092 
1093 			ic_dhcp_msgtype = mt;
1094 
1095 		}
1096 #endif /* IPCONFIG_DHCP */
1097 
1098 		ext = &b->exten[4];
1099 		while (ext < end && *ext != 0xff) {
1100 			u8 *opt = ext++;
1101 			if (*opt == 0)	/* Padding */
1102 				continue;
1103 			ext += *ext + 1;
1104 			if (ext < end)
1105 				ic_do_bootp_ext(opt);
1106 		}
1107 	}
1108 
1109 	/* We have a winner! */
1110 	ic_dev = dev;
1111 	ic_myaddr = b->your_ip;
1112 	ic_servaddr = b->server_ip;
1113 	if (ic_gateway == NONE && b->relay_ip)
1114 		ic_gateway = b->relay_ip;
1115 	if (ic_nameservers[0] == NONE)
1116 		ic_nameservers[0] = ic_servaddr;
1117 	ic_got_reply = IC_BOOTP;
1118 
1119 drop_unlock:
1120 	/* Show's over.  Nothing to see here.  */
1121 	spin_unlock(&ic_recv_lock);
1122 
1123 drop:
1124 	/* Throw the packet out. */
1125 	kfree_skb(skb);
1126 
1127 	return 0;
1128 }
1129 
1130 
1131 #endif
1132 
1133 
1134 /*
1135  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1136  */
1137 
1138 #ifdef IPCONFIG_DYNAMIC
1139 
1140 static int __init ic_dynamic(void)
1141 {
1142 	int retries;
1143 	struct ic_device *d;
1144 	unsigned long start_jiffies, timeout, jiff;
1145 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1146 	int do_rarp = ic_proto_have_if & IC_RARP;
1147 
1148 	/*
1149 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1150 	 * This routine gets only called when some pieces of information
1151 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1152 	 */
1153 	if (!ic_proto_enabled) {
1154 		pr_err("IP-Config: Incomplete network configuration information\n");
1155 		return -1;
1156 	}
1157 
1158 #ifdef IPCONFIG_BOOTP
1159 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1160 		pr_err("DHCP/BOOTP: No suitable device found\n");
1161 #endif
1162 #ifdef IPCONFIG_RARP
1163 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1164 		pr_err("RARP: No suitable device found\n");
1165 #endif
1166 
1167 	if (!ic_proto_have_if)
1168 		/* Error message already printed */
1169 		return -1;
1170 
1171 	/*
1172 	 * Setup protocols
1173 	 */
1174 #ifdef IPCONFIG_BOOTP
1175 	if (do_bootp)
1176 		ic_bootp_init();
1177 #endif
1178 #ifdef IPCONFIG_RARP
1179 	if (do_rarp)
1180 		ic_rarp_init();
1181 #endif
1182 
1183 	/*
1184 	 * Send requests and wait, until we get an answer. This loop
1185 	 * seems to be a terrible waste of CPU time, but actually there is
1186 	 * only one process running at all, so we don't need to use any
1187 	 * scheduler functions.
1188 	 * [Actually we could now, but the nothing else running note still
1189 	 *  applies.. - AC]
1190 	 */
1191 	pr_notice("Sending %s%s%s requests .",
1192 		  do_bootp
1193 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1194 		  (do_bootp && do_rarp) ? " and " : "",
1195 		  do_rarp ? "RARP" : "");
1196 
1197 	start_jiffies = jiffies;
1198 	d = ic_first_dev;
1199 	retries = CONF_SEND_RETRIES;
1200 	get_random_bytes(&timeout, sizeof(timeout));
1201 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1202 	for (;;) {
1203 		/* Track the device we are configuring */
1204 		ic_dev_xid = d->xid;
1205 
1206 #ifdef IPCONFIG_BOOTP
1207 		if (do_bootp && (d->able & IC_BOOTP))
1208 			ic_bootp_send_if(d, jiffies - start_jiffies);
1209 #endif
1210 #ifdef IPCONFIG_RARP
1211 		if (do_rarp && (d->able & IC_RARP))
1212 			ic_rarp_send_if(d);
1213 #endif
1214 
1215 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1216 		while (time_before(jiffies, jiff) && !ic_got_reply)
1217 			schedule_timeout_uninterruptible(1);
1218 #ifdef IPCONFIG_DHCP
1219 		/* DHCP isn't done until we get a DHCPACK. */
1220 		if ((ic_got_reply & IC_BOOTP) &&
1221 		    (ic_proto_enabled & IC_USE_DHCP) &&
1222 		    ic_dhcp_msgtype != DHCPACK) {
1223 			ic_got_reply = 0;
1224 			pr_cont(",");
1225 			continue;
1226 		}
1227 #endif /* IPCONFIG_DHCP */
1228 
1229 		if (ic_got_reply) {
1230 			pr_cont(" OK\n");
1231 			break;
1232 		}
1233 
1234 		if ((d = d->next))
1235 			continue;
1236 
1237 		if (! --retries) {
1238 			pr_cont(" timed out!\n");
1239 			break;
1240 		}
1241 
1242 		d = ic_first_dev;
1243 
1244 		timeout = timeout CONF_TIMEOUT_MULT;
1245 		if (timeout > CONF_TIMEOUT_MAX)
1246 			timeout = CONF_TIMEOUT_MAX;
1247 
1248 		pr_cont(".");
1249 	}
1250 
1251 #ifdef IPCONFIG_BOOTP
1252 	if (do_bootp)
1253 		ic_bootp_cleanup();
1254 #endif
1255 #ifdef IPCONFIG_RARP
1256 	if (do_rarp)
1257 		ic_rarp_cleanup();
1258 #endif
1259 
1260 	if (!ic_got_reply) {
1261 		ic_myaddr = NONE;
1262 		return -1;
1263 	}
1264 
1265 	printk("IP-Config: Got %s answer from %pI4, ",
1266 		((ic_got_reply & IC_RARP) ? "RARP"
1267 		 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1268 	       &ic_servaddr);
1269 	pr_cont("my address is %pI4\n", &ic_myaddr);
1270 
1271 	return 0;
1272 }
1273 
1274 #endif /* IPCONFIG_DYNAMIC */
1275 
1276 #ifdef CONFIG_PROC_FS
1277 
1278 static int pnp_seq_show(struct seq_file *seq, void *v)
1279 {
1280 	int i;
1281 
1282 	if (ic_proto_used & IC_PROTO)
1283 		seq_printf(seq, "#PROTO: %s\n",
1284 			   (ic_proto_used & IC_RARP) ? "RARP"
1285 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1286 	else
1287 		seq_puts(seq, "#MANUAL\n");
1288 
1289 	if (ic_domain[0])
1290 		seq_printf(seq,
1291 			   "domain %s\n", ic_domain);
1292 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1293 		if (ic_nameservers[i] != NONE)
1294 			seq_printf(seq, "nameserver %pI4\n",
1295 				   &ic_nameservers[i]);
1296 	}
1297 	if (ic_servaddr != NONE)
1298 		seq_printf(seq, "bootserver %pI4\n",
1299 			   &ic_servaddr);
1300 	return 0;
1301 }
1302 
1303 static int pnp_seq_open(struct inode *indoe, struct file *file)
1304 {
1305 	return single_open(file, pnp_seq_show, NULL);
1306 }
1307 
1308 static const struct file_operations pnp_seq_fops = {
1309 	.owner		= THIS_MODULE,
1310 	.open		= pnp_seq_open,
1311 	.read		= seq_read,
1312 	.llseek		= seq_lseek,
1313 	.release	= single_release,
1314 };
1315 #endif /* CONFIG_PROC_FS */
1316 
1317 /*
1318  *  Extract IP address from the parameter string if needed. Note that we
1319  *  need to have root_server_addr set _before_ IPConfig gets called as it
1320  *  can override it.
1321  */
1322 __be32 __init root_nfs_parse_addr(char *name)
1323 {
1324 	__be32 addr;
1325 	int octets = 0;
1326 	char *cp, *cq;
1327 
1328 	cp = cq = name;
1329 	while (octets < 4) {
1330 		while (*cp >= '0' && *cp <= '9')
1331 			cp++;
1332 		if (cp == cq || cp - cq > 3)
1333 			break;
1334 		if (*cp == '.' || octets == 3)
1335 			octets++;
1336 		if (octets < 4)
1337 			cp++;
1338 		cq = cp;
1339 	}
1340 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1341 		if (*cp == ':')
1342 			*cp++ = '\0';
1343 		addr = in_aton(name);
1344 		memmove(name, cp, strlen(cp) + 1);
1345 	} else
1346 		addr = NONE;
1347 
1348 	return addr;
1349 }
1350 
1351 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1352 
1353 static int __init wait_for_devices(void)
1354 {
1355 	int i;
1356 
1357 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1358 		struct net_device *dev;
1359 		int found = 0;
1360 
1361 		rtnl_lock();
1362 		for_each_netdev(&init_net, dev) {
1363 			if (ic_is_init_dev(dev)) {
1364 				found = 1;
1365 				break;
1366 			}
1367 		}
1368 		rtnl_unlock();
1369 		if (found)
1370 			return 0;
1371 		ssleep(1);
1372 	}
1373 	return -ENODEV;
1374 }
1375 
1376 /*
1377  *	IP Autoconfig dispatcher.
1378  */
1379 
1380 static int __init ip_auto_config(void)
1381 {
1382 	__be32 addr;
1383 #ifdef IPCONFIG_DYNAMIC
1384 	int retries = CONF_OPEN_RETRIES;
1385 #endif
1386 	int err;
1387 
1388 #ifdef CONFIG_PROC_FS
1389 	proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1390 #endif /* CONFIG_PROC_FS */
1391 
1392 	if (!ic_enable)
1393 		return 0;
1394 
1395 	DBG(("IP-Config: Entered.\n"));
1396 #ifdef IPCONFIG_DYNAMIC
1397  try_try_again:
1398 #endif
1399 	/* Wait for devices to appear */
1400 	err = wait_for_devices();
1401 	if (err)
1402 		return err;
1403 
1404 	/* Setup all network devices */
1405 	err = ic_open_devs();
1406 	if (err)
1407 		return err;
1408 
1409 	/* Give drivers a chance to settle */
1410 	msleep(CONF_POST_OPEN);
1411 
1412 	/*
1413 	 * If the config information is insufficient (e.g., our IP address or
1414 	 * IP address of the boot server is missing or we have multiple network
1415 	 * interfaces and no default was set), use BOOTP or RARP to get the
1416 	 * missing values.
1417 	 */
1418 	if (ic_myaddr == NONE ||
1419 #ifdef CONFIG_ROOT_NFS
1420 	    (root_server_addr == NONE &&
1421 	     ic_servaddr == NONE &&
1422 	     ROOT_DEV == Root_NFS) ||
1423 #endif
1424 	    ic_first_dev->next) {
1425 #ifdef IPCONFIG_DYNAMIC
1426 		if (ic_dynamic() < 0) {
1427 			ic_close_devs();
1428 
1429 			/*
1430 			 * I don't know why, but sometimes the
1431 			 * eepro100 driver (at least) gets upset and
1432 			 * doesn't work the first time it's opened.
1433 			 * But then if you close it and reopen it, it
1434 			 * works just fine.  So we need to try that at
1435 			 * least once before giving up.
1436 			 *
1437 			 * Also, if the root will be NFS-mounted, we
1438 			 * have nowhere to go if DHCP fails.  So we
1439 			 * just have to keep trying forever.
1440 			 *
1441 			 * 				-- Chip
1442 			 */
1443 #ifdef CONFIG_ROOT_NFS
1444 			if (ROOT_DEV ==  Root_NFS) {
1445 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1446 				goto try_try_again;
1447 			}
1448 #endif
1449 
1450 			if (--retries) {
1451 				pr_err("IP-Config: Reopening network devices...\n");
1452 				goto try_try_again;
1453 			}
1454 
1455 			/* Oh, well.  At least we tried. */
1456 			pr_err("IP-Config: Auto-configuration of network failed\n");
1457 			return -1;
1458 		}
1459 #else /* !DYNAMIC */
1460 		pr_err("IP-Config: Incomplete network configuration information\n");
1461 		ic_close_devs();
1462 		return -1;
1463 #endif /* IPCONFIG_DYNAMIC */
1464 	} else {
1465 		/* Device selected manually or only one device -> use it */
1466 		ic_dev = ic_first_dev->dev;
1467 	}
1468 
1469 	addr = root_nfs_parse_addr(root_server_path);
1470 	if (root_server_addr == NONE)
1471 		root_server_addr = addr;
1472 
1473 	/*
1474 	 * Use defaults wherever applicable.
1475 	 */
1476 	if (ic_defaults() < 0)
1477 		return -1;
1478 
1479 	/*
1480 	 * Close all network devices except the device we've
1481 	 * autoconfigured and set up routes.
1482 	 */
1483 	ic_close_devs();
1484 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1485 		return -1;
1486 
1487 	/*
1488 	 * Record which protocol was actually used.
1489 	 */
1490 #ifdef IPCONFIG_DYNAMIC
1491 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1492 #endif
1493 
1494 #ifndef IPCONFIG_SILENT
1495 	/*
1496 	 * Clue in the operator.
1497 	 */
1498 	pr_info("IP-Config: Complete:\n");
1499 	pr_info("     device=%s, addr=%pI4, mask=%pI4, gw=%pI4\n",
1500 		ic_dev->name, &ic_myaddr, &ic_netmask, &ic_gateway);
1501 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1502 		utsname()->nodename, ic_domain, utsname()->domainname);
1503 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1504 		&ic_servaddr, &root_server_addr, root_server_path);
1505 	if (ic_dev_mtu)
1506 		pr_cont(", mtu=%d", ic_dev_mtu);
1507 	pr_cont("\n");
1508 #endif /* !SILENT */
1509 
1510 	return 0;
1511 }
1512 
1513 late_initcall(ip_auto_config);
1514 
1515 
1516 /*
1517  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1518  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1519  */
1520 static int __init ic_proto_name(char *name)
1521 {
1522 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1523 		return 1;
1524 	}
1525 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1526 		return 0;
1527 	}
1528 #ifdef CONFIG_IP_PNP_DHCP
1529 	else if (!strcmp(name, "dhcp")) {
1530 		ic_proto_enabled &= ~IC_RARP;
1531 		return 1;
1532 	}
1533 #endif
1534 #ifdef CONFIG_IP_PNP_BOOTP
1535 	else if (!strcmp(name, "bootp")) {
1536 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1537 		return 1;
1538 	}
1539 #endif
1540 #ifdef CONFIG_IP_PNP_RARP
1541 	else if (!strcmp(name, "rarp")) {
1542 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1543 		return 1;
1544 	}
1545 #endif
1546 #ifdef IPCONFIG_DYNAMIC
1547 	else if (!strcmp(name, "both")) {
1548 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1549 		return 1;
1550 	}
1551 #endif
1552 	return 0;
1553 }
1554 
1555 static int __init ip_auto_config_setup(char *addrs)
1556 {
1557 	char *cp, *ip, *dp;
1558 	int num = 0;
1559 
1560 	ic_set_manually = 1;
1561 	ic_enable = 1;
1562 
1563 	/*
1564 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1565 	 * and skip the below static IP processing.
1566 	 */
1567 	if (ic_proto_name(addrs))
1568 		return 1;
1569 
1570 	/* If no static IP is given, turn off autoconfig and bail.  */
1571 	if (*addrs == 0 ||
1572 	    strcmp(addrs, "off") == 0 ||
1573 	    strcmp(addrs, "none") == 0) {
1574 		ic_enable = 0;
1575 		return 1;
1576 	}
1577 
1578 	/* Parse string for static IP assignment.  */
1579 	ip = addrs;
1580 	while (ip && *ip) {
1581 		if ((cp = strchr(ip, ':')))
1582 			*cp++ = '\0';
1583 		if (strlen(ip) > 0) {
1584 			DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1585 			switch (num) {
1586 			case 0:
1587 				if ((ic_myaddr = in_aton(ip)) == ANY)
1588 					ic_myaddr = NONE;
1589 				break;
1590 			case 1:
1591 				if ((ic_servaddr = in_aton(ip)) == ANY)
1592 					ic_servaddr = NONE;
1593 				break;
1594 			case 2:
1595 				if ((ic_gateway = in_aton(ip)) == ANY)
1596 					ic_gateway = NONE;
1597 				break;
1598 			case 3:
1599 				if ((ic_netmask = in_aton(ip)) == ANY)
1600 					ic_netmask = NONE;
1601 				break;
1602 			case 4:
1603 				if ((dp = strchr(ip, '.'))) {
1604 					*dp++ = '\0';
1605 					strlcpy(utsname()->domainname, dp,
1606 						sizeof(utsname()->domainname));
1607 				}
1608 				strlcpy(utsname()->nodename, ip,
1609 					sizeof(utsname()->nodename));
1610 				ic_host_name_set = 1;
1611 				break;
1612 			case 5:
1613 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1614 				break;
1615 			case 6:
1616 				if (ic_proto_name(ip) == 0 &&
1617 				    ic_myaddr == NONE) {
1618 					ic_enable = 0;
1619 				}
1620 				break;
1621 			}
1622 		}
1623 		ip = cp;
1624 		num++;
1625 	}
1626 
1627 	return 1;
1628 }
1629 
1630 static int __init nfsaddrs_config_setup(char *addrs)
1631 {
1632 	return ip_auto_config_setup(addrs);
1633 }
1634 
1635 static int __init vendor_class_identifier_setup(char *addrs)
1636 {
1637 	if (strlcpy(vendor_class_identifier, addrs,
1638 		    sizeof(vendor_class_identifier))
1639 	    >= sizeof(vendor_class_identifier))
1640 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1641 			vendor_class_identifier);
1642 	return 1;
1643 }
1644 
1645 __setup("ip=", ip_auto_config_setup);
1646 __setup("nfsaddrs=", nfsaddrs_config_setup);
1647 __setup("dhcpclass=", vendor_class_identifier_setup);
1648