xref: /openbmc/linux/net/ipv4/ipconfig.c (revision 2596e07a)
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 #if defined(CONFIG_IP_PNP_DHCP)
69 #define IPCONFIG_DHCP
70 #endif
71 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
72 #define IPCONFIG_BOOTP
73 #endif
74 #if defined(CONFIG_IP_PNP_RARP)
75 #define IPCONFIG_RARP
76 #endif
77 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
78 #define IPCONFIG_DYNAMIC
79 #endif
80 
81 /* Define the friendly delay before and after opening net devices */
82 #define CONF_POST_OPEN		10	/* After opening: 10 msecs */
83 #define CONF_CARRIER_TIMEOUT	120000	/* Wait for carrier timeout */
84 
85 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
86 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
87 #define CONF_SEND_RETRIES 	6	/* Send six requests per open */
88 #define CONF_INTER_TIMEOUT	(HZ)	/* Inter-device timeout: 1 second */
89 #define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
90 #define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
91 #define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
92 #define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
93 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
94 					   - '3' from resolv.h */
95 
96 #define NONE cpu_to_be32(INADDR_NONE)
97 #define ANY cpu_to_be32(INADDR_ANY)
98 
99 /*
100  * Public IP configuration
101  */
102 
103 /* This is used by platforms which might be able to set the ipconfig
104  * variables using firmware environment vars.  If this is set, it will
105  * ignore such firmware variables.
106  */
107 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
108 
109 static int ic_enable __initdata;		/* IP config enabled? */
110 
111 /* Protocol choice */
112 int ic_proto_enabled __initdata = 0
113 #ifdef IPCONFIG_BOOTP
114 			| IC_BOOTP
115 #endif
116 #ifdef CONFIG_IP_PNP_DHCP
117 			| IC_USE_DHCP
118 #endif
119 #ifdef IPCONFIG_RARP
120 			| IC_RARP
121 #endif
122 			;
123 
124 static int ic_host_name_set __initdata;	/* Host name set by us? */
125 
126 __be32 ic_myaddr = NONE;		/* My IP address */
127 static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
128 __be32 ic_gateway = NONE;	/* Gateway IP address */
129 
130 __be32 ic_addrservaddr = NONE;	/* IP Address of the IP addresses'server */
131 
132 __be32 ic_servaddr = NONE;	/* Boot server IP address */
133 
134 __be32 root_server_addr = NONE;	/* Address of NFS server */
135 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
136 
137 /* vendor class identifier */
138 static char vendor_class_identifier[253] __initdata;
139 
140 #if defined(CONFIG_IP_PNP_DHCP)
141 static char dhcp_client_identifier[253] __initdata;
142 #endif
143 
144 /* Persistent data: */
145 
146 #ifdef IPCONFIG_DYNAMIC
147 static int ic_proto_used;			/* Protocol used, if any */
148 #else
149 #define ic_proto_used 0
150 #endif
151 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
152 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
153 
154 /*
155  * Private state.
156  */
157 
158 /* Name of user-selected boot device */
159 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
160 
161 /* Protocols supported by available interfaces */
162 static int ic_proto_have_if __initdata;
163 
164 /* MTU for boot device */
165 static int ic_dev_mtu __initdata;
166 
167 #ifdef IPCONFIG_DYNAMIC
168 static DEFINE_SPINLOCK(ic_recv_lock);
169 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
170 #endif
171 #ifdef IPCONFIG_DHCP
172 static int ic_dhcp_msgtype __initdata;	/* DHCP msg type received */
173 #endif
174 
175 
176 /*
177  *	Network devices
178  */
179 
180 struct ic_device {
181 	struct ic_device *next;
182 	struct net_device *dev;
183 	unsigned short flags;
184 	short able;
185 	__be32 xid;
186 };
187 
188 static struct ic_device *ic_first_dev __initdata;	/* List of open device */
189 static struct net_device *ic_dev __initdata;		/* Selected device */
190 
191 static bool __init ic_is_init_dev(struct net_device *dev)
192 {
193 	if (dev->flags & IFF_LOOPBACK)
194 		return false;
195 	return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
196 	    (!(dev->flags & IFF_LOOPBACK) &&
197 	     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
198 	     strncmp(dev->name, "dummy", 5));
199 }
200 
201 static int __init ic_open_devs(void)
202 {
203 	struct ic_device *d, **last;
204 	struct net_device *dev;
205 	unsigned short oflags;
206 	unsigned long start, next_msg;
207 
208 	last = &ic_first_dev;
209 	rtnl_lock();
210 
211 	/* bring loopback and DSA master network devices up first */
212 	for_each_netdev(&init_net, dev) {
213 		if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
214 			continue;
215 		if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
216 			pr_err("IP-Config: Failed to open %s\n", dev->name);
217 	}
218 
219 	for_each_netdev(&init_net, dev) {
220 		if (ic_is_init_dev(dev)) {
221 			int able = 0;
222 			if (dev->mtu >= 364)
223 				able |= IC_BOOTP;
224 			else
225 				pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
226 					dev->name, dev->mtu);
227 			if (!(dev->flags & IFF_NOARP))
228 				able |= IC_RARP;
229 			able &= ic_proto_enabled;
230 			if (ic_proto_enabled && !able)
231 				continue;
232 			oflags = dev->flags;
233 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
234 				pr_err("IP-Config: Failed to open %s\n",
235 				       dev->name);
236 				continue;
237 			}
238 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
239 				rtnl_unlock();
240 				return -ENOMEM;
241 			}
242 			d->dev = dev;
243 			*last = d;
244 			last = &d->next;
245 			d->flags = oflags;
246 			d->able = able;
247 			if (able & IC_BOOTP)
248 				get_random_bytes(&d->xid, sizeof(__be32));
249 			else
250 				d->xid = 0;
251 			ic_proto_have_if |= able;
252 			pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
253 				 dev->name, able, d->xid);
254 		}
255 	}
256 
257 	/* no point in waiting if we could not bring up at least one device */
258 	if (!ic_first_dev)
259 		goto have_carrier;
260 
261 	/* wait for a carrier on at least one device */
262 	start = jiffies;
263 	next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
264 	while (time_before(jiffies, start +
265 			   msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
266 		int wait, elapsed;
267 
268 		for_each_netdev(&init_net, dev)
269 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
270 				goto have_carrier;
271 
272 		msleep(1);
273 
274 		if (time_before(jiffies, next_msg))
275 			continue;
276 
277 		elapsed = jiffies_to_msecs(jiffies - start);
278 		wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
279 		pr_info("Waiting up to %d more seconds for network.\n", wait);
280 		next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
281 	}
282 have_carrier:
283 	rtnl_unlock();
284 
285 	*last = NULL;
286 
287 	if (!ic_first_dev) {
288 		if (user_dev_name[0])
289 			pr_err("IP-Config: Device `%s' not found\n",
290 			       user_dev_name);
291 		else
292 			pr_err("IP-Config: No network devices available\n");
293 		return -ENODEV;
294 	}
295 	return 0;
296 }
297 
298 static void __init ic_close_devs(void)
299 {
300 	struct ic_device *d, *next;
301 	struct net_device *dev;
302 
303 	rtnl_lock();
304 	next = ic_first_dev;
305 	while ((d = next)) {
306 		next = d->next;
307 		dev = d->dev;
308 		if (dev != ic_dev && !netdev_uses_dsa(dev)) {
309 			pr_debug("IP-Config: Downing %s\n", dev->name);
310 			dev_change_flags(dev, d->flags);
311 		}
312 		kfree(d);
313 	}
314 	rtnl_unlock();
315 }
316 
317 /*
318  *	Interface to various network functions.
319  */
320 
321 static inline void
322 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
323 {
324 	sin->sin_family = AF_INET;
325 	sin->sin_addr.s_addr = addr;
326 	sin->sin_port = port;
327 }
328 
329 static int __init ic_devinet_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 = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
336 	set_fs(oldfs);
337 	return res;
338 }
339 
340 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
341 {
342 	int res;
343 
344 	mm_segment_t oldfs = get_fs();
345 	set_fs(get_ds());
346 	res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
347 	set_fs(oldfs);
348 	return res;
349 }
350 
351 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
352 {
353 	int res;
354 
355 	mm_segment_t oldfs = get_fs();
356 	set_fs(get_ds());
357 	res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
358 	set_fs(oldfs);
359 	return res;
360 }
361 
362 /*
363  *	Set up interface addresses and routes.
364  */
365 
366 static int __init ic_setup_if(void)
367 {
368 	struct ifreq ir;
369 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
370 	int err;
371 
372 	memset(&ir, 0, sizeof(ir));
373 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
374 	set_sockaddr(sin, ic_myaddr, 0);
375 	if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
376 		pr_err("IP-Config: Unable to set interface address (%d)\n",
377 		       err);
378 		return -1;
379 	}
380 	set_sockaddr(sin, ic_netmask, 0);
381 	if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
382 		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
383 		       err);
384 		return -1;
385 	}
386 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
387 	if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
388 		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
389 		       err);
390 		return -1;
391 	}
392 	/* Handle the case where we need non-standard MTU on the boot link (a network
393 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
394 	 * out, we'll try to muddle along.
395 	 */
396 	if (ic_dev_mtu != 0) {
397 		strcpy(ir.ifr_name, ic_dev->name);
398 		ir.ifr_mtu = ic_dev_mtu;
399 		if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
400 			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
401 			       ic_dev_mtu, err);
402 	}
403 	return 0;
404 }
405 
406 static int __init ic_setup_routes(void)
407 {
408 	/* No need to setup device routes, only the default route... */
409 
410 	if (ic_gateway != NONE) {
411 		struct rtentry rm;
412 		int err;
413 
414 		memset(&rm, 0, sizeof(rm));
415 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
416 			pr_err("IP-Config: Gateway not on directly connected network\n");
417 			return -1;
418 		}
419 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
420 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
421 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
422 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
423 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
424 			pr_err("IP-Config: Cannot add default route (%d)\n",
425 			       err);
426 			return -1;
427 		}
428 	}
429 
430 	return 0;
431 }
432 
433 /*
434  *	Fill in default values for all missing parameters.
435  */
436 
437 static int __init ic_defaults(void)
438 {
439 	/*
440 	 *	At this point we have no userspace running so need not
441 	 *	claim locks on system_utsname
442 	 */
443 
444 	if (!ic_host_name_set)
445 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
446 
447 	if (root_server_addr == NONE)
448 		root_server_addr = ic_servaddr;
449 
450 	if (ic_netmask == NONE) {
451 		if (IN_CLASSA(ntohl(ic_myaddr)))
452 			ic_netmask = htonl(IN_CLASSA_NET);
453 		else if (IN_CLASSB(ntohl(ic_myaddr)))
454 			ic_netmask = htonl(IN_CLASSB_NET);
455 		else if (IN_CLASSC(ntohl(ic_myaddr)))
456 			ic_netmask = htonl(IN_CLASSC_NET);
457 		else {
458 			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
459 			       &ic_myaddr);
460 			return -1;
461 		}
462 		pr_notice("IP-Config: Guessing netmask %pI4\n",
463 			  &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 	pr_debug("DHCP: Sending message type %d\n", mt);
675 
676 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
677 	e += 4;
678 
679 	*e++ = 53;		/* DHCP message type */
680 	*e++ = 1;
681 	*e++ = mt;
682 
683 	if (mt == DHCPREQUEST) {
684 		*e++ = 54;	/* Server ID (IP address) */
685 		*e++ = 4;
686 		memcpy(e, &ic_servaddr, 4);
687 		e += 4;
688 
689 		*e++ = 50;	/* Requested IP address */
690 		*e++ = 4;
691 		memcpy(e, &ic_myaddr, 4);
692 		e += 4;
693 	}
694 
695 	/* always? */
696 	{
697 		static const u8 ic_req_params[] = {
698 			1,	/* Subnet mask */
699 			3,	/* Default gateway */
700 			6,	/* DNS server */
701 			12,	/* Host name */
702 			15,	/* Domain name */
703 			17,	/* Boot path */
704 			26,	/* MTU */
705 			40,	/* NIS domain name */
706 		};
707 
708 		*e++ = 55;	/* Parameter request list */
709 		*e++ = sizeof(ic_req_params);
710 		memcpy(e, ic_req_params, sizeof(ic_req_params));
711 		e += sizeof(ic_req_params);
712 
713 		if (ic_host_name_set) {
714 			*e++ = 12;	/* host-name */
715 			len = strlen(utsname()->nodename);
716 			*e++ = len;
717 			memcpy(e, utsname()->nodename, len);
718 			e += len;
719 		}
720 		if (*vendor_class_identifier) {
721 			pr_info("DHCP: sending class identifier \"%s\"\n",
722 				vendor_class_identifier);
723 			*e++ = 60;	/* Class-identifier */
724 			len = strlen(vendor_class_identifier);
725 			*e++ = len;
726 			memcpy(e, vendor_class_identifier, len);
727 			e += len;
728 		}
729 		len = strlen(dhcp_client_identifier + 1);
730 		/* the minimum length of identifier is 2, include 1 byte type,
731 		 * and can not be larger than the length of options
732 		 */
733 		if (len >= 1 && len < 312 - (e - options) - 1) {
734 			*e++ = 61;
735 			*e++ = len + 1;
736 			memcpy(e, dhcp_client_identifier, len + 1);
737 			e += len + 1;
738 		}
739 	}
740 
741 	*e++ = 255;	/* End of the list */
742 }
743 
744 #endif /* IPCONFIG_DHCP */
745 
746 static void __init ic_bootp_init_ext(u8 *e)
747 {
748 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
749 	e += 4;
750 	*e++ = 1;		/* Subnet mask request */
751 	*e++ = 4;
752 	e += 4;
753 	*e++ = 3;		/* Default gateway request */
754 	*e++ = 4;
755 	e += 4;
756 	*e++ = 5;		/* Name server request */
757 	*e++ = 8;
758 	e += 8;
759 	*e++ = 12;		/* Host name request */
760 	*e++ = 32;
761 	e += 32;
762 	*e++ = 40;		/* NIS Domain name request */
763 	*e++ = 32;
764 	e += 32;
765 	*e++ = 17;		/* Boot path */
766 	*e++ = 40;
767 	e += 40;
768 
769 	*e++ = 57;		/* set extension buffer size for reply */
770 	*e++ = 2;
771 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
772 	*e++ = 150;
773 
774 	*e++ = 255;		/* End of the list */
775 }
776 
777 
778 /*
779  *  Initialize the DHCP/BOOTP mechanism.
780  */
781 static inline void __init ic_bootp_init(void)
782 {
783 	ic_nameservers_predef();
784 
785 	dev_add_pack(&bootp_packet_type);
786 }
787 
788 
789 /*
790  *  DHCP/BOOTP cleanup.
791  */
792 static inline void __init ic_bootp_cleanup(void)
793 {
794 	dev_remove_pack(&bootp_packet_type);
795 }
796 
797 
798 /*
799  *  Send DHCP/BOOTP request to single interface.
800  */
801 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
802 {
803 	struct net_device *dev = d->dev;
804 	struct sk_buff *skb;
805 	struct bootp_pkt *b;
806 	struct iphdr *h;
807 	int hlen = LL_RESERVED_SPACE(dev);
808 	int tlen = dev->needed_tailroom;
809 
810 	/* Allocate packet */
811 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
812 			GFP_KERNEL);
813 	if (!skb)
814 		return;
815 	skb_reserve(skb, hlen);
816 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
817 	memset(b, 0, sizeof(struct bootp_pkt));
818 
819 	/* Construct IP header */
820 	skb_reset_network_header(skb);
821 	h = ip_hdr(skb);
822 	h->version = 4;
823 	h->ihl = 5;
824 	h->tot_len = htons(sizeof(struct bootp_pkt));
825 	h->frag_off = htons(IP_DF);
826 	h->ttl = 64;
827 	h->protocol = IPPROTO_UDP;
828 	h->daddr = htonl(INADDR_BROADCAST);
829 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
830 
831 	/* Construct UDP header */
832 	b->udph.source = htons(68);
833 	b->udph.dest = htons(67);
834 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
835 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
836 
837 	/* Construct DHCP/BOOTP header */
838 	b->op = BOOTP_REQUEST;
839 	if (dev->type < 256) /* check for false types */
840 		b->htype = dev->type;
841 	else if (dev->type == ARPHRD_FDDI)
842 		b->htype = ARPHRD_ETHER;
843 	else {
844 		pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
845 			dev->name);
846 		b->htype = dev->type; /* can cause undefined behavior */
847 	}
848 
849 	/* server_ip and your_ip address are both already zero per RFC2131 */
850 	b->hlen = dev->addr_len;
851 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
852 	b->secs = htons(jiffies_diff / HZ);
853 	b->xid = d->xid;
854 
855 	/* add DHCP options or BOOTP extensions */
856 #ifdef IPCONFIG_DHCP
857 	if (ic_proto_enabled & IC_USE_DHCP)
858 		ic_dhcp_init_options(b->exten);
859 	else
860 #endif
861 		ic_bootp_init_ext(b->exten);
862 
863 	/* Chain packet down the line... */
864 	skb->dev = dev;
865 	skb->protocol = htons(ETH_P_IP);
866 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
867 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
868 		kfree_skb(skb);
869 		printk("E");
870 		return;
871 	}
872 
873 	if (dev_queue_xmit(skb) < 0)
874 		printk("E");
875 }
876 
877 
878 /*
879  *  Copy BOOTP-supplied string if not already set.
880  */
881 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
882 {
883 	if (!len)
884 		return 0;
885 	if (len > max-1)
886 		len = max-1;
887 	memcpy(dest, src, len);
888 	dest[len] = '\0';
889 	return 1;
890 }
891 
892 
893 /*
894  *  Process BOOTP extensions.
895  */
896 static void __init ic_do_bootp_ext(u8 *ext)
897 {
898 	u8 servers;
899 	int i;
900 	__be16 mtu;
901 
902 	u8 *c;
903 
904 	pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
905 	for (c=ext+2; c<ext+2+ext[1]; c++)
906 		pr_debug(" %02x", *c);
907 	pr_debug("\n");
908 
909 	switch (*ext++) {
910 	case 1:		/* Subnet mask */
911 		if (ic_netmask == NONE)
912 			memcpy(&ic_netmask, ext+1, 4);
913 		break;
914 	case 3:		/* Default gateway */
915 		if (ic_gateway == NONE)
916 			memcpy(&ic_gateway, ext+1, 4);
917 		break;
918 	case 6:		/* DNS server */
919 		servers= *ext/4;
920 		if (servers > CONF_NAMESERVERS_MAX)
921 			servers = CONF_NAMESERVERS_MAX;
922 		for (i = 0; i < servers; i++) {
923 			if (ic_nameservers[i] == NONE)
924 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
925 		}
926 		break;
927 	case 12:	/* Host name */
928 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
929 				__NEW_UTS_LEN);
930 		ic_host_name_set = 1;
931 		break;
932 	case 15:	/* Domain name (DNS) */
933 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
934 		break;
935 	case 17:	/* Root path */
936 		if (!root_server_path[0])
937 			ic_bootp_string(root_server_path, ext+1, *ext,
938 					sizeof(root_server_path));
939 		break;
940 	case 26:	/* Interface MTU */
941 		memcpy(&mtu, ext+1, sizeof(mtu));
942 		ic_dev_mtu = ntohs(mtu);
943 		break;
944 	case 40:	/* NIS Domain name (_not_ DNS) */
945 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
946 				__NEW_UTS_LEN);
947 		break;
948 	}
949 }
950 
951 
952 /*
953  *  Receive BOOTP reply.
954  */
955 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
956 {
957 	struct bootp_pkt *b;
958 	struct iphdr *h;
959 	struct ic_device *d;
960 	int len, ext_len;
961 
962 	if (!net_eq(dev_net(dev), &init_net))
963 		goto drop;
964 
965 	/* Perform verifications before taking the lock.  */
966 	if (skb->pkt_type == PACKET_OTHERHOST)
967 		goto drop;
968 
969 	skb = skb_share_check(skb, GFP_ATOMIC);
970 	if (!skb)
971 		return NET_RX_DROP;
972 
973 	if (!pskb_may_pull(skb,
974 			   sizeof(struct iphdr) +
975 			   sizeof(struct udphdr)))
976 		goto drop;
977 
978 	b = (struct bootp_pkt *)skb_network_header(skb);
979 	h = &b->iph;
980 
981 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
982 		goto drop;
983 
984 	/* Fragments are not supported */
985 	if (ip_is_fragment(h)) {
986 		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
987 		goto drop;
988 	}
989 
990 	if (skb->len < ntohs(h->tot_len))
991 		goto drop;
992 
993 	if (ip_fast_csum((char *) h, h->ihl))
994 		goto drop;
995 
996 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
997 		goto drop;
998 
999 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1000 		goto drop;
1001 
1002 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
1003 	ext_len = len - (sizeof(*b) -
1004 			 sizeof(struct iphdr) -
1005 			 sizeof(struct udphdr) -
1006 			 sizeof(b->exten));
1007 	if (ext_len < 0)
1008 		goto drop;
1009 
1010 	/* Ok the front looks good, make sure we can get at the rest.  */
1011 	if (!pskb_may_pull(skb, skb->len))
1012 		goto drop;
1013 
1014 	b = (struct bootp_pkt *)skb_network_header(skb);
1015 	h = &b->iph;
1016 
1017 	/* One reply at a time, please. */
1018 	spin_lock(&ic_recv_lock);
1019 
1020 	/* If we already have a reply, just drop the packet */
1021 	if (ic_got_reply)
1022 		goto drop_unlock;
1023 
1024 	/* Find the ic_device that the packet arrived on */
1025 	d = ic_first_dev;
1026 	while (d && d->dev != dev)
1027 		d = d->next;
1028 	if (!d)
1029 		goto drop_unlock;  /* should never happen */
1030 
1031 	/* Is it a reply to our BOOTP request? */
1032 	if (b->op != BOOTP_REPLY ||
1033 	    b->xid != d->xid) {
1034 		net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1035 				    b->op, b->xid);
1036 		goto drop_unlock;
1037 	}
1038 
1039 	/* Is it a reply for the device we are configuring? */
1040 	if (b->xid != ic_dev_xid) {
1041 		net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1042 		goto drop_unlock;
1043 	}
1044 
1045 	/* Parse extensions */
1046 	if (ext_len >= 4 &&
1047 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1048 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1049 		u8 *ext;
1050 
1051 #ifdef IPCONFIG_DHCP
1052 		if (ic_proto_enabled & IC_USE_DHCP) {
1053 			__be32 server_id = NONE;
1054 			int mt = 0;
1055 
1056 			ext = &b->exten[4];
1057 			while (ext < end && *ext != 0xff) {
1058 				u8 *opt = ext++;
1059 				if (*opt == 0)	/* Padding */
1060 					continue;
1061 				ext += *ext + 1;
1062 				if (ext >= end)
1063 					break;
1064 				switch (*opt) {
1065 				case 53:	/* Message type */
1066 					if (opt[1])
1067 						mt = opt[2];
1068 					break;
1069 				case 54:	/* Server ID (IP address) */
1070 					if (opt[1] >= 4)
1071 						memcpy(&server_id, opt + 2, 4);
1072 					break;
1073 				}
1074 			}
1075 
1076 			pr_debug("DHCP: Got message type %d\n", mt);
1077 
1078 			switch (mt) {
1079 			case DHCPOFFER:
1080 				/* While in the process of accepting one offer,
1081 				 * ignore all others.
1082 				 */
1083 				if (ic_myaddr != NONE)
1084 					goto drop_unlock;
1085 
1086 				/* Let's accept that offer. */
1087 				ic_myaddr = b->your_ip;
1088 				ic_servaddr = server_id;
1089 				pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1090 					 &ic_myaddr, &b->iph.saddr);
1091 				/* The DHCP indicated server address takes
1092 				 * precedence over the bootp header one if
1093 				 * they are different.
1094 				 */
1095 				if ((server_id != NONE) &&
1096 				    (b->server_ip != server_id))
1097 					b->server_ip = ic_servaddr;
1098 				break;
1099 
1100 			case DHCPACK:
1101 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1102 					goto drop_unlock;
1103 
1104 				/* Yeah! */
1105 				break;
1106 
1107 			default:
1108 				/* Urque.  Forget it*/
1109 				ic_myaddr = NONE;
1110 				ic_servaddr = NONE;
1111 				goto drop_unlock;
1112 			}
1113 
1114 			ic_dhcp_msgtype = mt;
1115 
1116 		}
1117 #endif /* IPCONFIG_DHCP */
1118 
1119 		ext = &b->exten[4];
1120 		while (ext < end && *ext != 0xff) {
1121 			u8 *opt = ext++;
1122 			if (*opt == 0)	/* Padding */
1123 				continue;
1124 			ext += *ext + 1;
1125 			if (ext < end)
1126 				ic_do_bootp_ext(opt);
1127 		}
1128 	}
1129 
1130 	/* We have a winner! */
1131 	ic_dev = dev;
1132 	ic_myaddr = b->your_ip;
1133 	ic_servaddr = b->server_ip;
1134 	ic_addrservaddr = b->iph.saddr;
1135 	if (ic_gateway == NONE && b->relay_ip)
1136 		ic_gateway = b->relay_ip;
1137 	if (ic_nameservers[0] == NONE)
1138 		ic_nameservers[0] = ic_servaddr;
1139 	ic_got_reply = IC_BOOTP;
1140 
1141 drop_unlock:
1142 	/* Show's over.  Nothing to see here.  */
1143 	spin_unlock(&ic_recv_lock);
1144 
1145 drop:
1146 	/* Throw the packet out. */
1147 	kfree_skb(skb);
1148 
1149 	return 0;
1150 }
1151 
1152 
1153 #endif
1154 
1155 
1156 /*
1157  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1158  */
1159 
1160 #ifdef IPCONFIG_DYNAMIC
1161 
1162 static int __init ic_dynamic(void)
1163 {
1164 	int retries;
1165 	struct ic_device *d;
1166 	unsigned long start_jiffies, timeout, jiff;
1167 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1168 	int do_rarp = ic_proto_have_if & IC_RARP;
1169 
1170 	/*
1171 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1172 	 * This routine gets only called when some pieces of information
1173 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1174 	 */
1175 	if (!ic_proto_enabled) {
1176 		pr_err("IP-Config: Incomplete network configuration information\n");
1177 		return -1;
1178 	}
1179 
1180 #ifdef IPCONFIG_BOOTP
1181 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1182 		pr_err("DHCP/BOOTP: No suitable device found\n");
1183 #endif
1184 #ifdef IPCONFIG_RARP
1185 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1186 		pr_err("RARP: No suitable device found\n");
1187 #endif
1188 
1189 	if (!ic_proto_have_if)
1190 		/* Error message already printed */
1191 		return -1;
1192 
1193 	/*
1194 	 * Setup protocols
1195 	 */
1196 #ifdef IPCONFIG_BOOTP
1197 	if (do_bootp)
1198 		ic_bootp_init();
1199 #endif
1200 #ifdef IPCONFIG_RARP
1201 	if (do_rarp)
1202 		ic_rarp_init();
1203 #endif
1204 
1205 	/*
1206 	 * Send requests and wait, until we get an answer. This loop
1207 	 * seems to be a terrible waste of CPU time, but actually there is
1208 	 * only one process running at all, so we don't need to use any
1209 	 * scheduler functions.
1210 	 * [Actually we could now, but the nothing else running note still
1211 	 *  applies.. - AC]
1212 	 */
1213 	pr_notice("Sending %s%s%s requests .",
1214 		  do_bootp
1215 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1216 		  (do_bootp && do_rarp) ? " and " : "",
1217 		  do_rarp ? "RARP" : "");
1218 
1219 	start_jiffies = jiffies;
1220 	d = ic_first_dev;
1221 	retries = CONF_SEND_RETRIES;
1222 	get_random_bytes(&timeout, sizeof(timeout));
1223 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1224 	for (;;) {
1225 #ifdef IPCONFIG_BOOTP
1226 		/* Track the device we are configuring */
1227 		ic_dev_xid = d->xid;
1228 
1229 		if (do_bootp && (d->able & IC_BOOTP))
1230 			ic_bootp_send_if(d, jiffies - start_jiffies);
1231 #endif
1232 #ifdef IPCONFIG_RARP
1233 		if (do_rarp && (d->able & IC_RARP))
1234 			ic_rarp_send_if(d);
1235 #endif
1236 
1237 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1238 		while (time_before(jiffies, jiff) && !ic_got_reply)
1239 			schedule_timeout_uninterruptible(1);
1240 #ifdef IPCONFIG_DHCP
1241 		/* DHCP isn't done until we get a DHCPACK. */
1242 		if ((ic_got_reply & IC_BOOTP) &&
1243 		    (ic_proto_enabled & IC_USE_DHCP) &&
1244 		    ic_dhcp_msgtype != DHCPACK) {
1245 			ic_got_reply = 0;
1246 			pr_cont(",");
1247 			continue;
1248 		}
1249 #endif /* IPCONFIG_DHCP */
1250 
1251 		if (ic_got_reply) {
1252 			pr_cont(" OK\n");
1253 			break;
1254 		}
1255 
1256 		if ((d = d->next))
1257 			continue;
1258 
1259 		if (! --retries) {
1260 			pr_cont(" timed out!\n");
1261 			break;
1262 		}
1263 
1264 		d = ic_first_dev;
1265 
1266 		timeout = timeout CONF_TIMEOUT_MULT;
1267 		if (timeout > CONF_TIMEOUT_MAX)
1268 			timeout = CONF_TIMEOUT_MAX;
1269 
1270 		pr_cont(".");
1271 	}
1272 
1273 #ifdef IPCONFIG_BOOTP
1274 	if (do_bootp)
1275 		ic_bootp_cleanup();
1276 #endif
1277 #ifdef IPCONFIG_RARP
1278 	if (do_rarp)
1279 		ic_rarp_cleanup();
1280 #endif
1281 
1282 	if (!ic_got_reply) {
1283 		ic_myaddr = NONE;
1284 		return -1;
1285 	}
1286 
1287 	pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1288 		((ic_got_reply & IC_RARP) ? "RARP"
1289 		: (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1290 		&ic_addrservaddr, &ic_myaddr);
1291 
1292 	return 0;
1293 }
1294 
1295 #endif /* IPCONFIG_DYNAMIC */
1296 
1297 #ifdef CONFIG_PROC_FS
1298 
1299 static int pnp_seq_show(struct seq_file *seq, void *v)
1300 {
1301 	int i;
1302 
1303 	if (ic_proto_used & IC_PROTO)
1304 		seq_printf(seq, "#PROTO: %s\n",
1305 			   (ic_proto_used & IC_RARP) ? "RARP"
1306 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1307 	else
1308 		seq_puts(seq, "#MANUAL\n");
1309 
1310 	if (ic_domain[0])
1311 		seq_printf(seq,
1312 			   "domain %s\n", ic_domain);
1313 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1314 		if (ic_nameservers[i] != NONE)
1315 			seq_printf(seq, "nameserver %pI4\n",
1316 				   &ic_nameservers[i]);
1317 	}
1318 	if (ic_servaddr != NONE)
1319 		seq_printf(seq, "bootserver %pI4\n",
1320 			   &ic_servaddr);
1321 	return 0;
1322 }
1323 
1324 static int pnp_seq_open(struct inode *indoe, struct file *file)
1325 {
1326 	return single_open(file, pnp_seq_show, NULL);
1327 }
1328 
1329 static const struct file_operations pnp_seq_fops = {
1330 	.owner		= THIS_MODULE,
1331 	.open		= pnp_seq_open,
1332 	.read		= seq_read,
1333 	.llseek		= seq_lseek,
1334 	.release	= single_release,
1335 };
1336 #endif /* CONFIG_PROC_FS */
1337 
1338 /*
1339  *  Extract IP address from the parameter string if needed. Note that we
1340  *  need to have root_server_addr set _before_ IPConfig gets called as it
1341  *  can override it.
1342  */
1343 __be32 __init root_nfs_parse_addr(char *name)
1344 {
1345 	__be32 addr;
1346 	int octets = 0;
1347 	char *cp, *cq;
1348 
1349 	cp = cq = name;
1350 	while (octets < 4) {
1351 		while (*cp >= '0' && *cp <= '9')
1352 			cp++;
1353 		if (cp == cq || cp - cq > 3)
1354 			break;
1355 		if (*cp == '.' || octets == 3)
1356 			octets++;
1357 		if (octets < 4)
1358 			cp++;
1359 		cq = cp;
1360 	}
1361 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1362 		if (*cp == ':')
1363 			*cp++ = '\0';
1364 		addr = in_aton(name);
1365 		memmove(name, cp, strlen(cp) + 1);
1366 	} else
1367 		addr = NONE;
1368 
1369 	return addr;
1370 }
1371 
1372 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1373 
1374 static int __init wait_for_devices(void)
1375 {
1376 	int i;
1377 
1378 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1379 		struct net_device *dev;
1380 		int found = 0;
1381 
1382 		rtnl_lock();
1383 		for_each_netdev(&init_net, dev) {
1384 			if (ic_is_init_dev(dev)) {
1385 				found = 1;
1386 				break;
1387 			}
1388 		}
1389 		rtnl_unlock();
1390 		if (found)
1391 			return 0;
1392 		ssleep(1);
1393 	}
1394 	return -ENODEV;
1395 }
1396 
1397 /*
1398  *	IP Autoconfig dispatcher.
1399  */
1400 
1401 static int __init ip_auto_config(void)
1402 {
1403 	__be32 addr;
1404 #ifdef IPCONFIG_DYNAMIC
1405 	int retries = CONF_OPEN_RETRIES;
1406 #endif
1407 	int err;
1408 	unsigned int i;
1409 
1410 #ifdef CONFIG_PROC_FS
1411 	proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1412 #endif /* CONFIG_PROC_FS */
1413 
1414 	if (!ic_enable)
1415 		return 0;
1416 
1417 	pr_debug("IP-Config: Entered.\n");
1418 #ifdef IPCONFIG_DYNAMIC
1419  try_try_again:
1420 #endif
1421 	/* Wait for devices to appear */
1422 	err = wait_for_devices();
1423 	if (err)
1424 		return err;
1425 
1426 	/* Setup all network devices */
1427 	err = ic_open_devs();
1428 	if (err)
1429 		return err;
1430 
1431 	/* Give drivers a chance to settle */
1432 	msleep(CONF_POST_OPEN);
1433 
1434 	/*
1435 	 * If the config information is insufficient (e.g., our IP address or
1436 	 * IP address of the boot server is missing or we have multiple network
1437 	 * interfaces and no default was set), use BOOTP or RARP to get the
1438 	 * missing values.
1439 	 */
1440 	if (ic_myaddr == NONE ||
1441 #ifdef CONFIG_ROOT_NFS
1442 	    (root_server_addr == NONE &&
1443 	     ic_servaddr == NONE &&
1444 	     ROOT_DEV == Root_NFS) ||
1445 #endif
1446 	    ic_first_dev->next) {
1447 #ifdef IPCONFIG_DYNAMIC
1448 		if (ic_dynamic() < 0) {
1449 			ic_close_devs();
1450 
1451 			/*
1452 			 * I don't know why, but sometimes the
1453 			 * eepro100 driver (at least) gets upset and
1454 			 * doesn't work the first time it's opened.
1455 			 * But then if you close it and reopen it, it
1456 			 * works just fine.  So we need to try that at
1457 			 * least once before giving up.
1458 			 *
1459 			 * Also, if the root will be NFS-mounted, we
1460 			 * have nowhere to go if DHCP fails.  So we
1461 			 * just have to keep trying forever.
1462 			 *
1463 			 * 				-- Chip
1464 			 */
1465 #ifdef CONFIG_ROOT_NFS
1466 			if (ROOT_DEV ==  Root_NFS) {
1467 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1468 				goto try_try_again;
1469 			}
1470 #endif
1471 
1472 			if (--retries) {
1473 				pr_err("IP-Config: Reopening network devices...\n");
1474 				goto try_try_again;
1475 			}
1476 
1477 			/* Oh, well.  At least we tried. */
1478 			pr_err("IP-Config: Auto-configuration of network failed\n");
1479 			return -1;
1480 		}
1481 #else /* !DYNAMIC */
1482 		pr_err("IP-Config: Incomplete network configuration information\n");
1483 		ic_close_devs();
1484 		return -1;
1485 #endif /* IPCONFIG_DYNAMIC */
1486 	} else {
1487 		/* Device selected manually or only one device -> use it */
1488 		ic_dev = ic_first_dev->dev;
1489 	}
1490 
1491 	addr = root_nfs_parse_addr(root_server_path);
1492 	if (root_server_addr == NONE)
1493 		root_server_addr = addr;
1494 
1495 	/*
1496 	 * Use defaults wherever applicable.
1497 	 */
1498 	if (ic_defaults() < 0)
1499 		return -1;
1500 
1501 	/*
1502 	 * Close all network devices except the device we've
1503 	 * autoconfigured and set up routes.
1504 	 */
1505 	ic_close_devs();
1506 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1507 		return -1;
1508 
1509 	/*
1510 	 * Record which protocol was actually used.
1511 	 */
1512 #ifdef IPCONFIG_DYNAMIC
1513 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1514 #endif
1515 
1516 #ifndef IPCONFIG_SILENT
1517 	/*
1518 	 * Clue in the operator.
1519 	 */
1520 	pr_info("IP-Config: Complete:\n");
1521 
1522 	pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1523 		ic_dev->name, ic_dev->addr_len, ic_dev->dev_addr,
1524 		&ic_myaddr, &ic_netmask, &ic_gateway);
1525 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1526 		utsname()->nodename, ic_domain, utsname()->domainname);
1527 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1528 		&ic_servaddr, &root_server_addr, root_server_path);
1529 	if (ic_dev_mtu)
1530 		pr_cont(", mtu=%d", ic_dev_mtu);
1531 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1532 		if (ic_nameservers[i] != NONE) {
1533 			pr_cont("     nameserver%u=%pI4",
1534 				i, &ic_nameservers[i]);
1535 			break;
1536 		}
1537 	for (i++; i < CONF_NAMESERVERS_MAX; i++)
1538 		if (ic_nameservers[i] != NONE)
1539 			pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1540 	pr_cont("\n");
1541 #endif /* !SILENT */
1542 
1543 	return 0;
1544 }
1545 
1546 late_initcall(ip_auto_config);
1547 
1548 
1549 /*
1550  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1551  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1552  */
1553 static int __init ic_proto_name(char *name)
1554 {
1555 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1556 		return 1;
1557 	}
1558 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1559 		return 0;
1560 	}
1561 #ifdef CONFIG_IP_PNP_DHCP
1562 	else if (!strncmp(name, "dhcp", 4)) {
1563 		char *client_id;
1564 
1565 		ic_proto_enabled &= ~IC_RARP;
1566 		client_id = strstr(name, "dhcp,");
1567 		if (client_id) {
1568 			char *v;
1569 
1570 			client_id = client_id + 5;
1571 			v = strchr(client_id, ',');
1572 			if (!v)
1573 				return 1;
1574 			*v = 0;
1575 			if (kstrtou8(client_id, 0, dhcp_client_identifier))
1576 				pr_debug("DHCP: Invalid client identifier type\n");
1577 			strncpy(dhcp_client_identifier + 1, v + 1, 251);
1578 			*v = ',';
1579 		}
1580 		return 1;
1581 	}
1582 #endif
1583 #ifdef CONFIG_IP_PNP_BOOTP
1584 	else if (!strcmp(name, "bootp")) {
1585 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1586 		return 1;
1587 	}
1588 #endif
1589 #ifdef CONFIG_IP_PNP_RARP
1590 	else if (!strcmp(name, "rarp")) {
1591 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1592 		return 1;
1593 	}
1594 #endif
1595 #ifdef IPCONFIG_DYNAMIC
1596 	else if (!strcmp(name, "both")) {
1597 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1598 		return 1;
1599 	}
1600 #endif
1601 	return 0;
1602 }
1603 
1604 static int __init ip_auto_config_setup(char *addrs)
1605 {
1606 	char *cp, *ip, *dp;
1607 	int num = 0;
1608 
1609 	ic_set_manually = 1;
1610 	ic_enable = 1;
1611 
1612 	/*
1613 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1614 	 * and skip the below static IP processing.
1615 	 */
1616 	if (ic_proto_name(addrs))
1617 		return 1;
1618 
1619 	/* If no static IP is given, turn off autoconfig and bail.  */
1620 	if (*addrs == 0 ||
1621 	    strcmp(addrs, "off") == 0 ||
1622 	    strcmp(addrs, "none") == 0) {
1623 		ic_enable = 0;
1624 		return 1;
1625 	}
1626 
1627 	ic_nameservers_predef();
1628 
1629 	/* Parse string for static IP assignment.  */
1630 	ip = addrs;
1631 	while (ip && *ip) {
1632 		if ((cp = strchr(ip, ':')))
1633 			*cp++ = '\0';
1634 		if (strlen(ip) > 0) {
1635 			pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1636 			switch (num) {
1637 			case 0:
1638 				if ((ic_myaddr = in_aton(ip)) == ANY)
1639 					ic_myaddr = NONE;
1640 				break;
1641 			case 1:
1642 				if ((ic_servaddr = in_aton(ip)) == ANY)
1643 					ic_servaddr = NONE;
1644 				break;
1645 			case 2:
1646 				if ((ic_gateway = in_aton(ip)) == ANY)
1647 					ic_gateway = NONE;
1648 				break;
1649 			case 3:
1650 				if ((ic_netmask = in_aton(ip)) == ANY)
1651 					ic_netmask = NONE;
1652 				break;
1653 			case 4:
1654 				if ((dp = strchr(ip, '.'))) {
1655 					*dp++ = '\0';
1656 					strlcpy(utsname()->domainname, dp,
1657 						sizeof(utsname()->domainname));
1658 				}
1659 				strlcpy(utsname()->nodename, ip,
1660 					sizeof(utsname()->nodename));
1661 				ic_host_name_set = 1;
1662 				break;
1663 			case 5:
1664 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1665 				break;
1666 			case 6:
1667 				if (ic_proto_name(ip) == 0 &&
1668 				    ic_myaddr == NONE) {
1669 					ic_enable = 0;
1670 				}
1671 				break;
1672 			case 7:
1673 				if (CONF_NAMESERVERS_MAX >= 1) {
1674 					ic_nameservers[0] = in_aton(ip);
1675 					if (ic_nameservers[0] == ANY)
1676 						ic_nameservers[0] = NONE;
1677 				}
1678 				break;
1679 			case 8:
1680 				if (CONF_NAMESERVERS_MAX >= 2) {
1681 					ic_nameservers[1] = in_aton(ip);
1682 					if (ic_nameservers[1] == ANY)
1683 						ic_nameservers[1] = NONE;
1684 				}
1685 				break;
1686 			}
1687 		}
1688 		ip = cp;
1689 		num++;
1690 	}
1691 
1692 	return 1;
1693 }
1694 __setup("ip=", ip_auto_config_setup);
1695 
1696 static int __init nfsaddrs_config_setup(char *addrs)
1697 {
1698 	return ip_auto_config_setup(addrs);
1699 }
1700 __setup("nfsaddrs=", nfsaddrs_config_setup);
1701 
1702 static int __init vendor_class_identifier_setup(char *addrs)
1703 {
1704 	if (strlcpy(vendor_class_identifier, addrs,
1705 		    sizeof(vendor_class_identifier))
1706 	    >= sizeof(vendor_class_identifier))
1707 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1708 			vendor_class_identifier);
1709 	return 1;
1710 }
1711 __setup("dhcpclass=", vendor_class_identifier_setup);
1712