xref: /linux/net/ipv4/ipconfig.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
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)	/* Inter-device timeout: 1 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;		/* 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;	/* 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_addrservaddr = NONE;	/* IP Address of the IP addresses'server */
140 
141 __be32 ic_servaddr = NONE;	/* Boot server IP address */
142 
143 __be32 root_server_addr = NONE;	/* Address of NFS server */
144 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
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;
164 
165 /* MTU for boot device */
166 static int ic_dev_mtu __initdata;
167 
168 #ifdef IPCONFIG_DYNAMIC
169 static DEFINE_SPINLOCK(ic_recv_lock);
170 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
171 #endif
172 #ifdef IPCONFIG_DHCP
173 static int ic_dhcp_msgtype __initdata;	/* 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;	/* List of open device */
190 static struct net_device *ic_dev __initdata;		/* 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, next_msg;
208 
209 	last = &ic_first_dev;
210 	rtnl_lock();
211 
212 	/* bring loopback and DSA master network devices up first */
213 	for_each_netdev(&init_net, dev) {
214 		if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
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 	next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
265 	while (time_before(jiffies, start +
266 			   msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
267 		int wait, elapsed;
268 
269 		for_each_netdev(&init_net, dev)
270 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
271 				goto have_carrier;
272 
273 		msleep(1);
274 
275 		if (time_before(jiffies, next_msg))
276 			continue;
277 
278 		elapsed = jiffies_to_msecs(jiffies - start);
279 		wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
280 		pr_info("Waiting up to %d more seconds for network.\n", wait);
281 		next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
282 	}
283 have_carrier:
284 	rtnl_unlock();
285 
286 	*last = NULL;
287 
288 	if (!ic_first_dev) {
289 		if (user_dev_name[0])
290 			pr_err("IP-Config: Device `%s' not found\n",
291 			       user_dev_name);
292 		else
293 			pr_err("IP-Config: No network devices available\n");
294 		return -ENODEV;
295 	}
296 	return 0;
297 }
298 
299 static void __init ic_close_devs(void)
300 {
301 	struct ic_device *d, *next;
302 	struct net_device *dev;
303 
304 	rtnl_lock();
305 	next = ic_first_dev;
306 	while ((d = next)) {
307 		next = d->next;
308 		dev = d->dev;
309 		if (dev != ic_dev && !netdev_uses_dsa(dev)) {
310 			DBG(("IP-Config: Downing %s\n", dev->name));
311 			dev_change_flags(dev, d->flags);
312 		}
313 		kfree(d);
314 	}
315 	rtnl_unlock();
316 }
317 
318 /*
319  *	Interface to various network functions.
320  */
321 
322 static inline void
323 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
324 {
325 	sin->sin_family = AF_INET;
326 	sin->sin_addr.s_addr = addr;
327 	sin->sin_port = port;
328 }
329 
330 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
331 {
332 	int res;
333 
334 	mm_segment_t oldfs = get_fs();
335 	set_fs(get_ds());
336 	res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
337 	set_fs(oldfs);
338 	return res;
339 }
340 
341 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
342 {
343 	int res;
344 
345 	mm_segment_t oldfs = get_fs();
346 	set_fs(get_ds());
347 	res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
348 	set_fs(oldfs);
349 	return res;
350 }
351 
352 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
353 {
354 	int res;
355 
356 	mm_segment_t oldfs = get_fs();
357 	set_fs(get_ds());
358 	res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
359 	set_fs(oldfs);
360 	return res;
361 }
362 
363 /*
364  *	Set up interface addresses and routes.
365  */
366 
367 static int __init ic_setup_if(void)
368 {
369 	struct ifreq ir;
370 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
371 	int err;
372 
373 	memset(&ir, 0, sizeof(ir));
374 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
375 	set_sockaddr(sin, ic_myaddr, 0);
376 	if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
377 		pr_err("IP-Config: Unable to set interface address (%d)\n",
378 		       err);
379 		return -1;
380 	}
381 	set_sockaddr(sin, ic_netmask, 0);
382 	if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
383 		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
384 		       err);
385 		return -1;
386 	}
387 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
388 	if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
389 		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
390 		       err);
391 		return -1;
392 	}
393 	/* Handle the case where we need non-standard MTU on the boot link (a network
394 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
395 	 * out, we'll try to muddle along.
396 	 */
397 	if (ic_dev_mtu != 0) {
398 		strcpy(ir.ifr_name, ic_dev->name);
399 		ir.ifr_mtu = ic_dev_mtu;
400 		if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
401 			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
402 			       ic_dev_mtu, err);
403 	}
404 	return 0;
405 }
406 
407 static int __init ic_setup_routes(void)
408 {
409 	/* No need to setup device routes, only the default route... */
410 
411 	if (ic_gateway != NONE) {
412 		struct rtentry rm;
413 		int err;
414 
415 		memset(&rm, 0, sizeof(rm));
416 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
417 			pr_err("IP-Config: Gateway not on directly connected network\n");
418 			return -1;
419 		}
420 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
421 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
422 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
423 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
424 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
425 			pr_err("IP-Config: Cannot add default route (%d)\n",
426 			       err);
427 			return -1;
428 		}
429 	}
430 
431 	return 0;
432 }
433 
434 /*
435  *	Fill in default values for all missing parameters.
436  */
437 
438 static int __init ic_defaults(void)
439 {
440 	/*
441 	 *	At this point we have no userspace running so need not
442 	 *	claim locks on system_utsname
443 	 */
444 
445 	if (!ic_host_name_set)
446 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
447 
448 	if (root_server_addr == NONE)
449 		root_server_addr = ic_servaddr;
450 
451 	if (ic_netmask == NONE) {
452 		if (IN_CLASSA(ntohl(ic_myaddr)))
453 			ic_netmask = htonl(IN_CLASSA_NET);
454 		else if (IN_CLASSB(ntohl(ic_myaddr)))
455 			ic_netmask = htonl(IN_CLASSB_NET);
456 		else if (IN_CLASSC(ntohl(ic_myaddr)))
457 			ic_netmask = htonl(IN_CLASSC_NET);
458 		else {
459 			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
460 			       &ic_myaddr);
461 			return -1;
462 		}
463 		printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
464 	}
465 
466 	return 0;
467 }
468 
469 /*
470  *	RARP support.
471  */
472 
473 #ifdef IPCONFIG_RARP
474 
475 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
476 
477 static struct packet_type rarp_packet_type __initdata = {
478 	.type =	cpu_to_be16(ETH_P_RARP),
479 	.func =	ic_rarp_recv,
480 };
481 
482 static inline void __init ic_rarp_init(void)
483 {
484 	dev_add_pack(&rarp_packet_type);
485 }
486 
487 static inline void __init ic_rarp_cleanup(void)
488 {
489 	dev_remove_pack(&rarp_packet_type);
490 }
491 
492 /*
493  *  Process received RARP packet.
494  */
495 static int __init
496 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
497 {
498 	struct arphdr *rarp;
499 	unsigned char *rarp_ptr;
500 	__be32 sip, tip;
501 	unsigned char *tha;		/* t for "target" */
502 	struct ic_device *d;
503 
504 	if (!net_eq(dev_net(dev), &init_net))
505 		goto drop;
506 
507 	skb = skb_share_check(skb, GFP_ATOMIC);
508 	if (!skb)
509 		return NET_RX_DROP;
510 
511 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
512 		goto drop;
513 
514 	/* Basic sanity checks can be done without the lock.  */
515 	rarp = (struct arphdr *)skb_transport_header(skb);
516 
517 	/* If this test doesn't pass, it's not IP, or we should
518 	 * ignore it anyway.
519 	 */
520 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
521 		goto drop;
522 
523 	/* If it's not a RARP reply, delete it. */
524 	if (rarp->ar_op != htons(ARPOP_RREPLY))
525 		goto drop;
526 
527 	/* If it's not Ethernet, delete it. */
528 	if (rarp->ar_pro != htons(ETH_P_IP))
529 		goto drop;
530 
531 	if (!pskb_may_pull(skb, arp_hdr_len(dev)))
532 		goto drop;
533 
534 	/* OK, it is all there and looks valid, process... */
535 	rarp = (struct arphdr *)skb_transport_header(skb);
536 	rarp_ptr = (unsigned char *) (rarp + 1);
537 
538 	/* One reply at a time, please. */
539 	spin_lock(&ic_recv_lock);
540 
541 	/* If we already have a reply, just drop the packet */
542 	if (ic_got_reply)
543 		goto drop_unlock;
544 
545 	/* Find the ic_device that the packet arrived on */
546 	d = ic_first_dev;
547 	while (d && d->dev != dev)
548 		d = d->next;
549 	if (!d)
550 		goto drop_unlock;	/* should never happen */
551 
552 	/* Extract variable-width fields */
553 	rarp_ptr += dev->addr_len;
554 	memcpy(&sip, rarp_ptr, 4);
555 	rarp_ptr += 4;
556 	tha = rarp_ptr;
557 	rarp_ptr += dev->addr_len;
558 	memcpy(&tip, rarp_ptr, 4);
559 
560 	/* Discard packets which are not meant for us. */
561 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
562 		goto drop_unlock;
563 
564 	/* Discard packets which are not from specified server. */
565 	if (ic_servaddr != NONE && ic_servaddr != sip)
566 		goto drop_unlock;
567 
568 	/* We have a winner! */
569 	ic_dev = dev;
570 	if (ic_myaddr == NONE)
571 		ic_myaddr = tip;
572 	ic_servaddr = sip;
573 	ic_addrservaddr = sip;
574 	ic_got_reply = IC_RARP;
575 
576 drop_unlock:
577 	/* Show's over.  Nothing to see here.  */
578 	spin_unlock(&ic_recv_lock);
579 
580 drop:
581 	/* Throw the packet out. */
582 	kfree_skb(skb);
583 	return 0;
584 }
585 
586 
587 /*
588  *  Send RARP request packet over a single interface.
589  */
590 static void __init ic_rarp_send_if(struct ic_device *d)
591 {
592 	struct net_device *dev = d->dev;
593 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
594 		 dev->dev_addr, dev->dev_addr);
595 }
596 #endif
597 
598 /*
599  *  Predefine Nameservers
600  */
601 static inline void __init ic_nameservers_predef(void)
602 {
603 	int i;
604 
605 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
606 		ic_nameservers[i] = NONE;
607 }
608 
609 /*
610  *	DHCP/BOOTP support.
611  */
612 
613 #ifdef IPCONFIG_BOOTP
614 
615 struct bootp_pkt {		/* BOOTP packet format */
616 	struct iphdr iph;	/* IP header */
617 	struct udphdr udph;	/* UDP header */
618 	u8 op;			/* 1=request, 2=reply */
619 	u8 htype;		/* HW address type */
620 	u8 hlen;		/* HW address length */
621 	u8 hops;		/* Used only by gateways */
622 	__be32 xid;		/* Transaction ID */
623 	__be16 secs;		/* Seconds since we started */
624 	__be16 flags;		/* Just what it says */
625 	__be32 client_ip;		/* Client's IP address if known */
626 	__be32 your_ip;		/* Assigned IP address */
627 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
628 	__be32 relay_ip;		/* IP address of BOOTP relay */
629 	u8 hw_addr[16];		/* Client's HW address */
630 	u8 serv_name[64];	/* Server host name */
631 	u8 boot_file[128];	/* Name of boot file */
632 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
633 };
634 
635 /* packet ops */
636 #define BOOTP_REQUEST	1
637 #define BOOTP_REPLY	2
638 
639 /* DHCP message types */
640 #define DHCPDISCOVER	1
641 #define DHCPOFFER	2
642 #define DHCPREQUEST	3
643 #define DHCPDECLINE	4
644 #define DHCPACK		5
645 #define DHCPNAK		6
646 #define DHCPRELEASE	7
647 #define DHCPINFORM	8
648 
649 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
650 
651 static struct packet_type bootp_packet_type __initdata = {
652 	.type =	cpu_to_be16(ETH_P_IP),
653 	.func =	ic_bootp_recv,
654 };
655 
656 static __be32 ic_dev_xid;		/* Device under configuration */
657 
658 /*
659  *  Initialize DHCP/BOOTP extension fields in the request.
660  */
661 
662 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
663 
664 #ifdef IPCONFIG_DHCP
665 
666 static void __init
667 ic_dhcp_init_options(u8 *options)
668 {
669 	u8 mt = ((ic_servaddr == NONE)
670 		 ? DHCPDISCOVER : DHCPREQUEST);
671 	u8 *e = options;
672 	int len;
673 
674 #ifdef IPCONFIG_DEBUG
675 	printk("DHCP: Sending message type %d\n", mt);
676 #endif
677 
678 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
679 	e += 4;
680 
681 	*e++ = 53;		/* DHCP message type */
682 	*e++ = 1;
683 	*e++ = mt;
684 
685 	if (mt == DHCPREQUEST) {
686 		*e++ = 54;	/* Server ID (IP address) */
687 		*e++ = 4;
688 		memcpy(e, &ic_servaddr, 4);
689 		e += 4;
690 
691 		*e++ = 50;	/* Requested IP address */
692 		*e++ = 4;
693 		memcpy(e, &ic_myaddr, 4);
694 		e += 4;
695 	}
696 
697 	/* always? */
698 	{
699 		static const u8 ic_req_params[] = {
700 			1,	/* Subnet mask */
701 			3,	/* Default gateway */
702 			6,	/* DNS server */
703 			12,	/* Host name */
704 			15,	/* Domain name */
705 			17,	/* Boot path */
706 			26,	/* MTU */
707 			40,	/* NIS domain name */
708 		};
709 
710 		*e++ = 55;	/* Parameter request list */
711 		*e++ = sizeof(ic_req_params);
712 		memcpy(e, ic_req_params, sizeof(ic_req_params));
713 		e += sizeof(ic_req_params);
714 
715 		if (ic_host_name_set) {
716 			*e++ = 12;	/* host-name */
717 			len = strlen(utsname()->nodename);
718 			*e++ = len;
719 			memcpy(e, utsname()->nodename, len);
720 			e += len;
721 		}
722 		if (*vendor_class_identifier) {
723 			pr_info("DHCP: sending class identifier \"%s\"\n",
724 				vendor_class_identifier);
725 			*e++ = 60;	/* Class-identifier */
726 			len = strlen(vendor_class_identifier);
727 			*e++ = len;
728 			memcpy(e, vendor_class_identifier, len);
729 			e += len;
730 		}
731 	}
732 
733 	*e++ = 255;	/* End of the list */
734 }
735 
736 #endif /* IPCONFIG_DHCP */
737 
738 static void __init ic_bootp_init_ext(u8 *e)
739 {
740 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
741 	e += 4;
742 	*e++ = 1;		/* Subnet mask request */
743 	*e++ = 4;
744 	e += 4;
745 	*e++ = 3;		/* Default gateway request */
746 	*e++ = 4;
747 	e += 4;
748 	*e++ = 5;		/* Name server request */
749 	*e++ = 8;
750 	e += 8;
751 	*e++ = 12;		/* Host name request */
752 	*e++ = 32;
753 	e += 32;
754 	*e++ = 40;		/* NIS Domain name request */
755 	*e++ = 32;
756 	e += 32;
757 	*e++ = 17;		/* Boot path */
758 	*e++ = 40;
759 	e += 40;
760 
761 	*e++ = 57;		/* set extension buffer size for reply */
762 	*e++ = 2;
763 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
764 	*e++ = 150;
765 
766 	*e++ = 255;		/* End of the list */
767 }
768 
769 
770 /*
771  *  Initialize the DHCP/BOOTP mechanism.
772  */
773 static inline void __init ic_bootp_init(void)
774 {
775 	ic_nameservers_predef();
776 
777 	dev_add_pack(&bootp_packet_type);
778 }
779 
780 
781 /*
782  *  DHCP/BOOTP cleanup.
783  */
784 static inline void __init ic_bootp_cleanup(void)
785 {
786 	dev_remove_pack(&bootp_packet_type);
787 }
788 
789 
790 /*
791  *  Send DHCP/BOOTP request to single interface.
792  */
793 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
794 {
795 	struct net_device *dev = d->dev;
796 	struct sk_buff *skb;
797 	struct bootp_pkt *b;
798 	struct iphdr *h;
799 	int hlen = LL_RESERVED_SPACE(dev);
800 	int tlen = dev->needed_tailroom;
801 
802 	/* Allocate packet */
803 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
804 			GFP_KERNEL);
805 	if (!skb)
806 		return;
807 	skb_reserve(skb, hlen);
808 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
809 	memset(b, 0, sizeof(struct bootp_pkt));
810 
811 	/* Construct IP header */
812 	skb_reset_network_header(skb);
813 	h = ip_hdr(skb);
814 	h->version = 4;
815 	h->ihl = 5;
816 	h->tot_len = htons(sizeof(struct bootp_pkt));
817 	h->frag_off = htons(IP_DF);
818 	h->ttl = 64;
819 	h->protocol = IPPROTO_UDP;
820 	h->daddr = htonl(INADDR_BROADCAST);
821 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
822 
823 	/* Construct UDP header */
824 	b->udph.source = htons(68);
825 	b->udph.dest = htons(67);
826 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
827 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
828 
829 	/* Construct DHCP/BOOTP header */
830 	b->op = BOOTP_REQUEST;
831 	if (dev->type < 256) /* check for false types */
832 		b->htype = dev->type;
833 	else if (dev->type == ARPHRD_FDDI)
834 		b->htype = ARPHRD_ETHER;
835 	else {
836 		printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
837 		b->htype = dev->type; /* can cause undefined behavior */
838 	}
839 
840 	/* server_ip and your_ip address are both already zero per RFC2131 */
841 	b->hlen = dev->addr_len;
842 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
843 	b->secs = htons(jiffies_diff / HZ);
844 	b->xid = d->xid;
845 
846 	/* add DHCP options or BOOTP extensions */
847 #ifdef IPCONFIG_DHCP
848 	if (ic_proto_enabled & IC_USE_DHCP)
849 		ic_dhcp_init_options(b->exten);
850 	else
851 #endif
852 		ic_bootp_init_ext(b->exten);
853 
854 	/* Chain packet down the line... */
855 	skb->dev = dev;
856 	skb->protocol = htons(ETH_P_IP);
857 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
858 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
859 		kfree_skb(skb);
860 		printk("E");
861 		return;
862 	}
863 
864 	if (dev_queue_xmit(skb) < 0)
865 		printk("E");
866 }
867 
868 
869 /*
870  *  Copy BOOTP-supplied string if not already set.
871  */
872 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
873 {
874 	if (!len)
875 		return 0;
876 	if (len > max-1)
877 		len = max-1;
878 	memcpy(dest, src, len);
879 	dest[len] = '\0';
880 	return 1;
881 }
882 
883 
884 /*
885  *  Process BOOTP extensions.
886  */
887 static void __init ic_do_bootp_ext(u8 *ext)
888 {
889 	u8 servers;
890 	int i;
891 	__be16 mtu;
892 
893 #ifdef IPCONFIG_DEBUG
894 	u8 *c;
895 
896 	printk("DHCP/BOOTP: Got extension %d:",*ext);
897 	for (c=ext+2; c<ext+2+ext[1]; c++)
898 		printk(" %02x", *c);
899 	printk("\n");
900 #endif
901 
902 	switch (*ext++) {
903 	case 1:		/* Subnet mask */
904 		if (ic_netmask == NONE)
905 			memcpy(&ic_netmask, ext+1, 4);
906 		break;
907 	case 3:		/* Default gateway */
908 		if (ic_gateway == NONE)
909 			memcpy(&ic_gateway, ext+1, 4);
910 		break;
911 	case 6:		/* DNS server */
912 		servers= *ext/4;
913 		if (servers > CONF_NAMESERVERS_MAX)
914 			servers = CONF_NAMESERVERS_MAX;
915 		for (i = 0; i < servers; i++) {
916 			if (ic_nameservers[i] == NONE)
917 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
918 		}
919 		break;
920 	case 12:	/* Host name */
921 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
922 				__NEW_UTS_LEN);
923 		ic_host_name_set = 1;
924 		break;
925 	case 15:	/* Domain name (DNS) */
926 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
927 		break;
928 	case 17:	/* Root path */
929 		if (!root_server_path[0])
930 			ic_bootp_string(root_server_path, ext+1, *ext,
931 					sizeof(root_server_path));
932 		break;
933 	case 26:	/* Interface MTU */
934 		memcpy(&mtu, ext+1, sizeof(mtu));
935 		ic_dev_mtu = ntohs(mtu);
936 		break;
937 	case 40:	/* NIS Domain name (_not_ DNS) */
938 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
939 				__NEW_UTS_LEN);
940 		break;
941 	}
942 }
943 
944 
945 /*
946  *  Receive BOOTP reply.
947  */
948 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
949 {
950 	struct bootp_pkt *b;
951 	struct iphdr *h;
952 	struct ic_device *d;
953 	int len, ext_len;
954 
955 	if (!net_eq(dev_net(dev), &init_net))
956 		goto drop;
957 
958 	/* Perform verifications before taking the lock.  */
959 	if (skb->pkt_type == PACKET_OTHERHOST)
960 		goto drop;
961 
962 	skb = skb_share_check(skb, GFP_ATOMIC);
963 	if (!skb)
964 		return NET_RX_DROP;
965 
966 	if (!pskb_may_pull(skb,
967 			   sizeof(struct iphdr) +
968 			   sizeof(struct udphdr)))
969 		goto drop;
970 
971 	b = (struct bootp_pkt *)skb_network_header(skb);
972 	h = &b->iph;
973 
974 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
975 		goto drop;
976 
977 	/* Fragments are not supported */
978 	if (ip_is_fragment(h)) {
979 		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
980 		goto drop;
981 	}
982 
983 	if (skb->len < ntohs(h->tot_len))
984 		goto drop;
985 
986 	if (ip_fast_csum((char *) h, h->ihl))
987 		goto drop;
988 
989 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
990 		goto drop;
991 
992 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
993 		goto drop;
994 
995 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
996 	ext_len = len - (sizeof(*b) -
997 			 sizeof(struct iphdr) -
998 			 sizeof(struct udphdr) -
999 			 sizeof(b->exten));
1000 	if (ext_len < 0)
1001 		goto drop;
1002 
1003 	/* Ok the front looks good, make sure we can get at the rest.  */
1004 	if (!pskb_may_pull(skb, skb->len))
1005 		goto drop;
1006 
1007 	b = (struct bootp_pkt *)skb_network_header(skb);
1008 	h = &b->iph;
1009 
1010 	/* One reply at a time, please. */
1011 	spin_lock(&ic_recv_lock);
1012 
1013 	/* If we already have a reply, just drop the packet */
1014 	if (ic_got_reply)
1015 		goto drop_unlock;
1016 
1017 	/* Find the ic_device that the packet arrived on */
1018 	d = ic_first_dev;
1019 	while (d && d->dev != dev)
1020 		d = d->next;
1021 	if (!d)
1022 		goto drop_unlock;  /* should never happen */
1023 
1024 	/* Is it a reply to our BOOTP request? */
1025 	if (b->op != BOOTP_REPLY ||
1026 	    b->xid != d->xid) {
1027 		net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1028 				    b->op, b->xid);
1029 		goto drop_unlock;
1030 	}
1031 
1032 	/* Is it a reply for the device we are configuring? */
1033 	if (b->xid != ic_dev_xid) {
1034 		net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1035 		goto drop_unlock;
1036 	}
1037 
1038 	/* Parse extensions */
1039 	if (ext_len >= 4 &&
1040 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1041 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1042 		u8 *ext;
1043 
1044 #ifdef IPCONFIG_DHCP
1045 		if (ic_proto_enabled & IC_USE_DHCP) {
1046 			__be32 server_id = NONE;
1047 			int mt = 0;
1048 
1049 			ext = &b->exten[4];
1050 			while (ext < end && *ext != 0xff) {
1051 				u8 *opt = ext++;
1052 				if (*opt == 0)	/* Padding */
1053 					continue;
1054 				ext += *ext + 1;
1055 				if (ext >= end)
1056 					break;
1057 				switch (*opt) {
1058 				case 53:	/* Message type */
1059 					if (opt[1])
1060 						mt = opt[2];
1061 					break;
1062 				case 54:	/* Server ID (IP address) */
1063 					if (opt[1] >= 4)
1064 						memcpy(&server_id, opt + 2, 4);
1065 					break;
1066 				}
1067 			}
1068 
1069 #ifdef IPCONFIG_DEBUG
1070 			printk("DHCP: Got message type %d\n", mt);
1071 #endif
1072 
1073 			switch (mt) {
1074 			case DHCPOFFER:
1075 				/* While in the process of accepting one offer,
1076 				 * ignore all others.
1077 				 */
1078 				if (ic_myaddr != NONE)
1079 					goto drop_unlock;
1080 
1081 				/* Let's accept that offer. */
1082 				ic_myaddr = b->your_ip;
1083 				ic_servaddr = server_id;
1084 #ifdef IPCONFIG_DEBUG
1085 				printk("DHCP: Offered address %pI4 by server %pI4\n",
1086 				       &ic_myaddr, &b->iph.saddr);
1087 #endif
1088 				/* The DHCP indicated server address takes
1089 				 * precedence over the bootp header one if
1090 				 * they are different.
1091 				 */
1092 				if ((server_id != NONE) &&
1093 				    (b->server_ip != server_id))
1094 					b->server_ip = ic_servaddr;
1095 				break;
1096 
1097 			case DHCPACK:
1098 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1099 					goto drop_unlock;
1100 
1101 				/* Yeah! */
1102 				break;
1103 
1104 			default:
1105 				/* Urque.  Forget it*/
1106 				ic_myaddr = NONE;
1107 				ic_servaddr = NONE;
1108 				goto drop_unlock;
1109 			}
1110 
1111 			ic_dhcp_msgtype = mt;
1112 
1113 		}
1114 #endif /* IPCONFIG_DHCP */
1115 
1116 		ext = &b->exten[4];
1117 		while (ext < end && *ext != 0xff) {
1118 			u8 *opt = ext++;
1119 			if (*opt == 0)	/* Padding */
1120 				continue;
1121 			ext += *ext + 1;
1122 			if (ext < end)
1123 				ic_do_bootp_ext(opt);
1124 		}
1125 	}
1126 
1127 	/* We have a winner! */
1128 	ic_dev = dev;
1129 	ic_myaddr = b->your_ip;
1130 	ic_servaddr = b->server_ip;
1131 	ic_addrservaddr = b->iph.saddr;
1132 	if (ic_gateway == NONE && b->relay_ip)
1133 		ic_gateway = b->relay_ip;
1134 	if (ic_nameservers[0] == NONE)
1135 		ic_nameservers[0] = ic_servaddr;
1136 	ic_got_reply = IC_BOOTP;
1137 
1138 drop_unlock:
1139 	/* Show's over.  Nothing to see here.  */
1140 	spin_unlock(&ic_recv_lock);
1141 
1142 drop:
1143 	/* Throw the packet out. */
1144 	kfree_skb(skb);
1145 
1146 	return 0;
1147 }
1148 
1149 
1150 #endif
1151 
1152 
1153 /*
1154  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1155  */
1156 
1157 #ifdef IPCONFIG_DYNAMIC
1158 
1159 static int __init ic_dynamic(void)
1160 {
1161 	int retries;
1162 	struct ic_device *d;
1163 	unsigned long start_jiffies, timeout, jiff;
1164 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1165 	int do_rarp = ic_proto_have_if & IC_RARP;
1166 
1167 	/*
1168 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1169 	 * This routine gets only called when some pieces of information
1170 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1171 	 */
1172 	if (!ic_proto_enabled) {
1173 		pr_err("IP-Config: Incomplete network configuration information\n");
1174 		return -1;
1175 	}
1176 
1177 #ifdef IPCONFIG_BOOTP
1178 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1179 		pr_err("DHCP/BOOTP: No suitable device found\n");
1180 #endif
1181 #ifdef IPCONFIG_RARP
1182 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1183 		pr_err("RARP: No suitable device found\n");
1184 #endif
1185 
1186 	if (!ic_proto_have_if)
1187 		/* Error message already printed */
1188 		return -1;
1189 
1190 	/*
1191 	 * Setup protocols
1192 	 */
1193 #ifdef IPCONFIG_BOOTP
1194 	if (do_bootp)
1195 		ic_bootp_init();
1196 #endif
1197 #ifdef IPCONFIG_RARP
1198 	if (do_rarp)
1199 		ic_rarp_init();
1200 #endif
1201 
1202 	/*
1203 	 * Send requests and wait, until we get an answer. This loop
1204 	 * seems to be a terrible waste of CPU time, but actually there is
1205 	 * only one process running at all, so we don't need to use any
1206 	 * scheduler functions.
1207 	 * [Actually we could now, but the nothing else running note still
1208 	 *  applies.. - AC]
1209 	 */
1210 	pr_notice("Sending %s%s%s requests .",
1211 		  do_bootp
1212 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1213 		  (do_bootp && do_rarp) ? " and " : "",
1214 		  do_rarp ? "RARP" : "");
1215 
1216 	start_jiffies = jiffies;
1217 	d = ic_first_dev;
1218 	retries = CONF_SEND_RETRIES;
1219 	get_random_bytes(&timeout, sizeof(timeout));
1220 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1221 	for (;;) {
1222 #ifdef IPCONFIG_BOOTP
1223 		/* Track the device we are configuring */
1224 		ic_dev_xid = d->xid;
1225 
1226 		if (do_bootp && (d->able & IC_BOOTP))
1227 			ic_bootp_send_if(d, jiffies - start_jiffies);
1228 #endif
1229 #ifdef IPCONFIG_RARP
1230 		if (do_rarp && (d->able & IC_RARP))
1231 			ic_rarp_send_if(d);
1232 #endif
1233 
1234 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1235 		while (time_before(jiffies, jiff) && !ic_got_reply)
1236 			schedule_timeout_uninterruptible(1);
1237 #ifdef IPCONFIG_DHCP
1238 		/* DHCP isn't done until we get a DHCPACK. */
1239 		if ((ic_got_reply & IC_BOOTP) &&
1240 		    (ic_proto_enabled & IC_USE_DHCP) &&
1241 		    ic_dhcp_msgtype != DHCPACK) {
1242 			ic_got_reply = 0;
1243 			pr_cont(",");
1244 			continue;
1245 		}
1246 #endif /* IPCONFIG_DHCP */
1247 
1248 		if (ic_got_reply) {
1249 			pr_cont(" OK\n");
1250 			break;
1251 		}
1252 
1253 		if ((d = d->next))
1254 			continue;
1255 
1256 		if (! --retries) {
1257 			pr_cont(" timed out!\n");
1258 			break;
1259 		}
1260 
1261 		d = ic_first_dev;
1262 
1263 		timeout = timeout CONF_TIMEOUT_MULT;
1264 		if (timeout > CONF_TIMEOUT_MAX)
1265 			timeout = CONF_TIMEOUT_MAX;
1266 
1267 		pr_cont(".");
1268 	}
1269 
1270 #ifdef IPCONFIG_BOOTP
1271 	if (do_bootp)
1272 		ic_bootp_cleanup();
1273 #endif
1274 #ifdef IPCONFIG_RARP
1275 	if (do_rarp)
1276 		ic_rarp_cleanup();
1277 #endif
1278 
1279 	if (!ic_got_reply) {
1280 		ic_myaddr = NONE;
1281 		return -1;
1282 	}
1283 
1284 	printk("IP-Config: Got %s answer from %pI4, ",
1285 		((ic_got_reply & IC_RARP) ? "RARP"
1286 		 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1287 	       &ic_addrservaddr);
1288 	pr_cont("my address is %pI4\n", &ic_myaddr);
1289 
1290 	return 0;
1291 }
1292 
1293 #endif /* IPCONFIG_DYNAMIC */
1294 
1295 #ifdef CONFIG_PROC_FS
1296 
1297 static int pnp_seq_show(struct seq_file *seq, void *v)
1298 {
1299 	int i;
1300 
1301 	if (ic_proto_used & IC_PROTO)
1302 		seq_printf(seq, "#PROTO: %s\n",
1303 			   (ic_proto_used & IC_RARP) ? "RARP"
1304 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1305 	else
1306 		seq_puts(seq, "#MANUAL\n");
1307 
1308 	if (ic_domain[0])
1309 		seq_printf(seq,
1310 			   "domain %s\n", ic_domain);
1311 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1312 		if (ic_nameservers[i] != NONE)
1313 			seq_printf(seq, "nameserver %pI4\n",
1314 				   &ic_nameservers[i]);
1315 	}
1316 	if (ic_servaddr != NONE)
1317 		seq_printf(seq, "bootserver %pI4\n",
1318 			   &ic_servaddr);
1319 	return 0;
1320 }
1321 
1322 static int pnp_seq_open(struct inode *indoe, struct file *file)
1323 {
1324 	return single_open(file, pnp_seq_show, NULL);
1325 }
1326 
1327 static const struct file_operations pnp_seq_fops = {
1328 	.owner		= THIS_MODULE,
1329 	.open		= pnp_seq_open,
1330 	.read		= seq_read,
1331 	.llseek		= seq_lseek,
1332 	.release	= single_release,
1333 };
1334 #endif /* CONFIG_PROC_FS */
1335 
1336 /*
1337  *  Extract IP address from the parameter string if needed. Note that we
1338  *  need to have root_server_addr set _before_ IPConfig gets called as it
1339  *  can override it.
1340  */
1341 __be32 __init root_nfs_parse_addr(char *name)
1342 {
1343 	__be32 addr;
1344 	int octets = 0;
1345 	char *cp, *cq;
1346 
1347 	cp = cq = name;
1348 	while (octets < 4) {
1349 		while (*cp >= '0' && *cp <= '9')
1350 			cp++;
1351 		if (cp == cq || cp - cq > 3)
1352 			break;
1353 		if (*cp == '.' || octets == 3)
1354 			octets++;
1355 		if (octets < 4)
1356 			cp++;
1357 		cq = cp;
1358 	}
1359 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1360 		if (*cp == ':')
1361 			*cp++ = '\0';
1362 		addr = in_aton(name);
1363 		memmove(name, cp, strlen(cp) + 1);
1364 	} else
1365 		addr = NONE;
1366 
1367 	return addr;
1368 }
1369 
1370 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1371 
1372 static int __init wait_for_devices(void)
1373 {
1374 	int i;
1375 
1376 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1377 		struct net_device *dev;
1378 		int found = 0;
1379 
1380 		rtnl_lock();
1381 		for_each_netdev(&init_net, dev) {
1382 			if (ic_is_init_dev(dev)) {
1383 				found = 1;
1384 				break;
1385 			}
1386 		}
1387 		rtnl_unlock();
1388 		if (found)
1389 			return 0;
1390 		ssleep(1);
1391 	}
1392 	return -ENODEV;
1393 }
1394 
1395 /*
1396  *	IP Autoconfig dispatcher.
1397  */
1398 
1399 static int __init ip_auto_config(void)
1400 {
1401 	__be32 addr;
1402 #ifdef IPCONFIG_DYNAMIC
1403 	int retries = CONF_OPEN_RETRIES;
1404 #endif
1405 	int err;
1406 	unsigned int i;
1407 
1408 #ifdef CONFIG_PROC_FS
1409 	proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1410 #endif /* CONFIG_PROC_FS */
1411 
1412 	if (!ic_enable)
1413 		return 0;
1414 
1415 	DBG(("IP-Config: Entered.\n"));
1416 #ifdef IPCONFIG_DYNAMIC
1417  try_try_again:
1418 #endif
1419 	/* Wait for devices to appear */
1420 	err = wait_for_devices();
1421 	if (err)
1422 		return err;
1423 
1424 	/* Setup all network devices */
1425 	err = ic_open_devs();
1426 	if (err)
1427 		return err;
1428 
1429 	/* Give drivers a chance to settle */
1430 	msleep(CONF_POST_OPEN);
1431 
1432 	/*
1433 	 * If the config information is insufficient (e.g., our IP address or
1434 	 * IP address of the boot server is missing or we have multiple network
1435 	 * interfaces and no default was set), use BOOTP or RARP to get the
1436 	 * missing values.
1437 	 */
1438 	if (ic_myaddr == NONE ||
1439 #ifdef CONFIG_ROOT_NFS
1440 	    (root_server_addr == NONE &&
1441 	     ic_servaddr == NONE &&
1442 	     ROOT_DEV == Root_NFS) ||
1443 #endif
1444 	    ic_first_dev->next) {
1445 #ifdef IPCONFIG_DYNAMIC
1446 		if (ic_dynamic() < 0) {
1447 			ic_close_devs();
1448 
1449 			/*
1450 			 * I don't know why, but sometimes the
1451 			 * eepro100 driver (at least) gets upset and
1452 			 * doesn't work the first time it's opened.
1453 			 * But then if you close it and reopen it, it
1454 			 * works just fine.  So we need to try that at
1455 			 * least once before giving up.
1456 			 *
1457 			 * Also, if the root will be NFS-mounted, we
1458 			 * have nowhere to go if DHCP fails.  So we
1459 			 * just have to keep trying forever.
1460 			 *
1461 			 * 				-- Chip
1462 			 */
1463 #ifdef CONFIG_ROOT_NFS
1464 			if (ROOT_DEV ==  Root_NFS) {
1465 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1466 				goto try_try_again;
1467 			}
1468 #endif
1469 
1470 			if (--retries) {
1471 				pr_err("IP-Config: Reopening network devices...\n");
1472 				goto try_try_again;
1473 			}
1474 
1475 			/* Oh, well.  At least we tried. */
1476 			pr_err("IP-Config: Auto-configuration of network failed\n");
1477 			return -1;
1478 		}
1479 #else /* !DYNAMIC */
1480 		pr_err("IP-Config: Incomplete network configuration information\n");
1481 		ic_close_devs();
1482 		return -1;
1483 #endif /* IPCONFIG_DYNAMIC */
1484 	} else {
1485 		/* Device selected manually or only one device -> use it */
1486 		ic_dev = ic_first_dev->dev;
1487 	}
1488 
1489 	addr = root_nfs_parse_addr(root_server_path);
1490 	if (root_server_addr == NONE)
1491 		root_server_addr = addr;
1492 
1493 	/*
1494 	 * Use defaults wherever applicable.
1495 	 */
1496 	if (ic_defaults() < 0)
1497 		return -1;
1498 
1499 	/*
1500 	 * Close all network devices except the device we've
1501 	 * autoconfigured and set up routes.
1502 	 */
1503 	ic_close_devs();
1504 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1505 		return -1;
1506 
1507 	/*
1508 	 * Record which protocol was actually used.
1509 	 */
1510 #ifdef IPCONFIG_DYNAMIC
1511 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1512 #endif
1513 
1514 #ifndef IPCONFIG_SILENT
1515 	/*
1516 	 * Clue in the operator.
1517 	 */
1518 	pr_info("IP-Config: Complete:\n");
1519 
1520 	pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1521 		ic_dev->name, ic_dev->addr_len, ic_dev->dev_addr,
1522 		&ic_myaddr, &ic_netmask, &ic_gateway);
1523 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1524 		utsname()->nodename, ic_domain, utsname()->domainname);
1525 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1526 		&ic_servaddr, &root_server_addr, root_server_path);
1527 	if (ic_dev_mtu)
1528 		pr_cont(", mtu=%d", ic_dev_mtu);
1529 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1530 		if (ic_nameservers[i] != NONE) {
1531 			pr_info("     nameserver%u=%pI4",
1532 				i, &ic_nameservers[i]);
1533 			break;
1534 		}
1535 	for (i++; i < CONF_NAMESERVERS_MAX; i++)
1536 		if (ic_nameservers[i] != NONE)
1537 			pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1538 	pr_cont("\n");
1539 #endif /* !SILENT */
1540 
1541 	return 0;
1542 }
1543 
1544 late_initcall(ip_auto_config);
1545 
1546 
1547 /*
1548  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1549  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1550  */
1551 static int __init ic_proto_name(char *name)
1552 {
1553 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1554 		return 1;
1555 	}
1556 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1557 		return 0;
1558 	}
1559 #ifdef CONFIG_IP_PNP_DHCP
1560 	else if (!strcmp(name, "dhcp")) {
1561 		ic_proto_enabled &= ~IC_RARP;
1562 		return 1;
1563 	}
1564 #endif
1565 #ifdef CONFIG_IP_PNP_BOOTP
1566 	else if (!strcmp(name, "bootp")) {
1567 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1568 		return 1;
1569 	}
1570 #endif
1571 #ifdef CONFIG_IP_PNP_RARP
1572 	else if (!strcmp(name, "rarp")) {
1573 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1574 		return 1;
1575 	}
1576 #endif
1577 #ifdef IPCONFIG_DYNAMIC
1578 	else if (!strcmp(name, "both")) {
1579 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1580 		return 1;
1581 	}
1582 #endif
1583 	return 0;
1584 }
1585 
1586 static int __init ip_auto_config_setup(char *addrs)
1587 {
1588 	char *cp, *ip, *dp;
1589 	int num = 0;
1590 
1591 	ic_set_manually = 1;
1592 	ic_enable = 1;
1593 
1594 	/*
1595 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1596 	 * and skip the below static IP processing.
1597 	 */
1598 	if (ic_proto_name(addrs))
1599 		return 1;
1600 
1601 	/* If no static IP is given, turn off autoconfig and bail.  */
1602 	if (*addrs == 0 ||
1603 	    strcmp(addrs, "off") == 0 ||
1604 	    strcmp(addrs, "none") == 0) {
1605 		ic_enable = 0;
1606 		return 1;
1607 	}
1608 
1609 	ic_nameservers_predef();
1610 
1611 	/* Parse string for static IP assignment.  */
1612 	ip = addrs;
1613 	while (ip && *ip) {
1614 		if ((cp = strchr(ip, ':')))
1615 			*cp++ = '\0';
1616 		if (strlen(ip) > 0) {
1617 			DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1618 			switch (num) {
1619 			case 0:
1620 				if ((ic_myaddr = in_aton(ip)) == ANY)
1621 					ic_myaddr = NONE;
1622 				break;
1623 			case 1:
1624 				if ((ic_servaddr = in_aton(ip)) == ANY)
1625 					ic_servaddr = NONE;
1626 				break;
1627 			case 2:
1628 				if ((ic_gateway = in_aton(ip)) == ANY)
1629 					ic_gateway = NONE;
1630 				break;
1631 			case 3:
1632 				if ((ic_netmask = in_aton(ip)) == ANY)
1633 					ic_netmask = NONE;
1634 				break;
1635 			case 4:
1636 				if ((dp = strchr(ip, '.'))) {
1637 					*dp++ = '\0';
1638 					strlcpy(utsname()->domainname, dp,
1639 						sizeof(utsname()->domainname));
1640 				}
1641 				strlcpy(utsname()->nodename, ip,
1642 					sizeof(utsname()->nodename));
1643 				ic_host_name_set = 1;
1644 				break;
1645 			case 5:
1646 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1647 				break;
1648 			case 6:
1649 				if (ic_proto_name(ip) == 0 &&
1650 				    ic_myaddr == NONE) {
1651 					ic_enable = 0;
1652 				}
1653 				break;
1654 			case 7:
1655 				if (CONF_NAMESERVERS_MAX >= 1) {
1656 					ic_nameservers[0] = in_aton(ip);
1657 					if (ic_nameservers[0] == ANY)
1658 						ic_nameservers[0] = NONE;
1659 				}
1660 				break;
1661 			case 8:
1662 				if (CONF_NAMESERVERS_MAX >= 2) {
1663 					ic_nameservers[1] = in_aton(ip);
1664 					if (ic_nameservers[1] == ANY)
1665 						ic_nameservers[1] = NONE;
1666 				}
1667 				break;
1668 			}
1669 		}
1670 		ip = cp;
1671 		num++;
1672 	}
1673 
1674 	return 1;
1675 }
1676 __setup("ip=", ip_auto_config_setup);
1677 
1678 static int __init nfsaddrs_config_setup(char *addrs)
1679 {
1680 	return ip_auto_config_setup(addrs);
1681 }
1682 __setup("nfsaddrs=", nfsaddrs_config_setup);
1683 
1684 static int __init vendor_class_identifier_setup(char *addrs)
1685 {
1686 	if (strlcpy(vendor_class_identifier, addrs,
1687 		    sizeof(vendor_class_identifier))
1688 	    >= sizeof(vendor_class_identifier))
1689 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1690 			vendor_class_identifier);
1691 	return 1;
1692 }
1693 __setup("dhcpclass=", vendor_class_identifier_setup);
1694