xref: /openbmc/linux/net/ipv4/ipconfig.c (revision 5ff32883)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
4  *  user-supplied information to configure own IP address and routes.
5  *
6  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
7  *
8  *  Derived from network configuration code in fs/nfs/nfsroot.c,
9  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
10  *
11  *  BOOTP rewritten to construct and analyse packets itself instead
12  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
13  *					     -- MJ, December 1998
14  *
15  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
16  *  initialization scheme.
17  *	- Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
18  *
19  *  DHCP support added.  To users this looks like a whole separate
20  *  protocol, but we know it's just a bag on the side of BOOTP.
21  *		-- Chip Salzenberg <chip@valinux.com>, May 2000
22  *
23  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
24  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
25  *
26  *  Merged changes from 2.2.19 into 2.4.3
27  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
28  *
29  *  Multiple Nameservers in /proc/net/pnp
30  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
31  *
32  *  NTP servers in /proc/net/ipconfig/ntp_servers
33  *              --  Chris Novakovic <chris@chrisn.me.uk>, April 2018
34  */
35 
36 #include <linux/types.h>
37 #include <linux/string.h>
38 #include <linux/kernel.h>
39 #include <linux/jiffies.h>
40 #include <linux/random.h>
41 #include <linux/init.h>
42 #include <linux/utsname.h>
43 #include <linux/in.h>
44 #include <linux/if.h>
45 #include <linux/inet.h>
46 #include <linux/inetdevice.h>
47 #include <linux/netdevice.h>
48 #include <linux/if_arp.h>
49 #include <linux/skbuff.h>
50 #include <linux/ip.h>
51 #include <linux/socket.h>
52 #include <linux/route.h>
53 #include <linux/udp.h>
54 #include <linux/proc_fs.h>
55 #include <linux/seq_file.h>
56 #include <linux/major.h>
57 #include <linux/root_dev.h>
58 #include <linux/delay.h>
59 #include <linux/nfs_fs.h>
60 #include <linux/slab.h>
61 #include <linux/export.h>
62 #include <net/net_namespace.h>
63 #include <net/arp.h>
64 #include <net/dsa.h>
65 #include <net/ip.h>
66 #include <net/ipconfig.h>
67 #include <net/route.h>
68 
69 #include <linux/uaccess.h>
70 #include <net/checksum.h>
71 #include <asm/processor.h>
72 
73 #if defined(CONFIG_IP_PNP_DHCP)
74 #define IPCONFIG_DHCP
75 #endif
76 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
77 #define IPCONFIG_BOOTP
78 #endif
79 #if defined(CONFIG_IP_PNP_RARP)
80 #define IPCONFIG_RARP
81 #endif
82 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
83 #define IPCONFIG_DYNAMIC
84 #endif
85 
86 /* Define the friendly delay before and after opening net devices */
87 #define CONF_POST_OPEN		10	/* After opening: 10 msecs */
88 #define CONF_CARRIER_TIMEOUT	120000	/* Wait for carrier timeout */
89 
90 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
91 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
92 #define CONF_SEND_RETRIES 	6	/* Send six requests per open */
93 #define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
94 #define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
95 #define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
96 #define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
97 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
98 					   - '3' from resolv.h */
99 #define CONF_NTP_SERVERS_MAX   3	/* Maximum number of NTP servers */
100 
101 #define NONE cpu_to_be32(INADDR_NONE)
102 #define ANY cpu_to_be32(INADDR_ANY)
103 
104 /*
105  * Public IP configuration
106  */
107 
108 /* This is used by platforms which might be able to set the ipconfig
109  * variables using firmware environment vars.  If this is set, it will
110  * ignore such firmware variables.
111  */
112 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
113 
114 static int ic_enable __initdata;		/* IP config enabled? */
115 
116 /* Protocol choice */
117 int ic_proto_enabled __initdata = 0
118 #ifdef IPCONFIG_BOOTP
119 			| IC_BOOTP
120 #endif
121 #ifdef CONFIG_IP_PNP_DHCP
122 			| IC_USE_DHCP
123 #endif
124 #ifdef IPCONFIG_RARP
125 			| IC_RARP
126 #endif
127 			;
128 
129 static int ic_host_name_set __initdata;	/* Host name set by us? */
130 
131 __be32 ic_myaddr = NONE;		/* My IP address */
132 static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
133 __be32 ic_gateway = NONE;	/* Gateway IP address */
134 
135 #ifdef IPCONFIG_DYNAMIC
136 static __be32 ic_addrservaddr = NONE;	/* IP Address of the IP addresses'server */
137 #endif
138 
139 __be32 ic_servaddr = NONE;	/* Boot server IP address */
140 
141 __be32 root_server_addr = NONE;	/* Address of NFS server */
142 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
143 
144 /* vendor class identifier */
145 static char vendor_class_identifier[253] __initdata;
146 
147 #if defined(CONFIG_IP_PNP_DHCP)
148 static char dhcp_client_identifier[253] __initdata;
149 #endif
150 
151 /* Persistent data: */
152 
153 #ifdef IPCONFIG_DYNAMIC
154 static int ic_proto_used;			/* Protocol used, if any */
155 #else
156 #define ic_proto_used 0
157 #endif
158 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
159 static __be32 ic_ntp_servers[CONF_NTP_SERVERS_MAX]; /* NTP server IP addresses */
160 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
161 
162 /*
163  * Private state.
164  */
165 
166 /* Name of user-selected boot device */
167 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
168 
169 /* Protocols supported by available interfaces */
170 static int ic_proto_have_if __initdata;
171 
172 /* MTU for boot device */
173 static int ic_dev_mtu __initdata;
174 
175 #ifdef IPCONFIG_DYNAMIC
176 static DEFINE_SPINLOCK(ic_recv_lock);
177 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
178 #endif
179 #ifdef IPCONFIG_DHCP
180 static int ic_dhcp_msgtype __initdata;	/* DHCP msg type received */
181 #endif
182 
183 
184 /*
185  *	Network devices
186  */
187 
188 struct ic_device {
189 	struct ic_device *next;
190 	struct net_device *dev;
191 	unsigned short flags;
192 	short able;
193 	__be32 xid;
194 };
195 
196 static struct ic_device *ic_first_dev __initdata;	/* List of open device */
197 static struct ic_device *ic_dev __initdata;		/* Selected device */
198 
199 static bool __init ic_is_init_dev(struct net_device *dev)
200 {
201 	if (dev->flags & IFF_LOOPBACK)
202 		return false;
203 	return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
204 	    (!(dev->flags & IFF_LOOPBACK) &&
205 	     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
206 	     strncmp(dev->name, "dummy", 5));
207 }
208 
209 static int __init ic_open_devs(void)
210 {
211 	struct ic_device *d, **last;
212 	struct net_device *dev;
213 	unsigned short oflags;
214 	unsigned long start, next_msg;
215 
216 	last = &ic_first_dev;
217 	rtnl_lock();
218 
219 	/* bring loopback and DSA master network devices up first */
220 	for_each_netdev(&init_net, dev) {
221 		if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
222 			continue;
223 		if (dev_change_flags(dev, dev->flags | IFF_UP, NULL) < 0)
224 			pr_err("IP-Config: Failed to open %s\n", dev->name);
225 	}
226 
227 	for_each_netdev(&init_net, dev) {
228 		if (ic_is_init_dev(dev)) {
229 			int able = 0;
230 			if (dev->mtu >= 364)
231 				able |= IC_BOOTP;
232 			else
233 				pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
234 					dev->name, dev->mtu);
235 			if (!(dev->flags & IFF_NOARP))
236 				able |= IC_RARP;
237 			able &= ic_proto_enabled;
238 			if (ic_proto_enabled && !able)
239 				continue;
240 			oflags = dev->flags;
241 			if (dev_change_flags(dev, oflags | IFF_UP, NULL) < 0) {
242 				pr_err("IP-Config: Failed to open %s\n",
243 				       dev->name);
244 				continue;
245 			}
246 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
247 				rtnl_unlock();
248 				return -ENOMEM;
249 			}
250 			d->dev = dev;
251 			*last = d;
252 			last = &d->next;
253 			d->flags = oflags;
254 			d->able = able;
255 			if (able & IC_BOOTP)
256 				get_random_bytes(&d->xid, sizeof(__be32));
257 			else
258 				d->xid = 0;
259 			ic_proto_have_if |= able;
260 			pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
261 				 dev->name, able, d->xid);
262 		}
263 	}
264 
265 	/* no point in waiting if we could not bring up at least one device */
266 	if (!ic_first_dev)
267 		goto have_carrier;
268 
269 	/* wait for a carrier on at least one device */
270 	start = jiffies;
271 	next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
272 	while (time_before(jiffies, start +
273 			   msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
274 		int wait, elapsed;
275 
276 		for_each_netdev(&init_net, dev)
277 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
278 				goto have_carrier;
279 
280 		msleep(1);
281 
282 		if (time_before(jiffies, next_msg))
283 			continue;
284 
285 		elapsed = jiffies_to_msecs(jiffies - start);
286 		wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
287 		pr_info("Waiting up to %d more seconds for network.\n", wait);
288 		next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
289 	}
290 have_carrier:
291 	rtnl_unlock();
292 
293 	*last = NULL;
294 
295 	if (!ic_first_dev) {
296 		if (user_dev_name[0])
297 			pr_err("IP-Config: Device `%s' not found\n",
298 			       user_dev_name);
299 		else
300 			pr_err("IP-Config: No network devices available\n");
301 		return -ENODEV;
302 	}
303 	return 0;
304 }
305 
306 static void __init ic_close_devs(void)
307 {
308 	struct ic_device *d, *next;
309 	struct net_device *dev;
310 
311 	rtnl_lock();
312 	next = ic_first_dev;
313 	while ((d = next)) {
314 		next = d->next;
315 		dev = d->dev;
316 		if (d != ic_dev && !netdev_uses_dsa(dev)) {
317 			pr_debug("IP-Config: Downing %s\n", dev->name);
318 			dev_change_flags(dev, d->flags, NULL);
319 		}
320 		kfree(d);
321 	}
322 	rtnl_unlock();
323 }
324 
325 /*
326  *	Interface to various network functions.
327  */
328 
329 static inline void
330 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
331 {
332 	sin->sin_family = AF_INET;
333 	sin->sin_addr.s_addr = addr;
334 	sin->sin_port = port;
335 }
336 
337 /*
338  *	Set up interface addresses and routes.
339  */
340 
341 static int __init ic_setup_if(void)
342 {
343 	struct ifreq ir;
344 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
345 	int err;
346 
347 	memset(&ir, 0, sizeof(ir));
348 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
349 	set_sockaddr(sin, ic_myaddr, 0);
350 	if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) {
351 		pr_err("IP-Config: Unable to set interface address (%d)\n",
352 		       err);
353 		return -1;
354 	}
355 	set_sockaddr(sin, ic_netmask, 0);
356 	if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) {
357 		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
358 		       err);
359 		return -1;
360 	}
361 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
362 	if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) {
363 		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
364 		       err);
365 		return -1;
366 	}
367 	/* Handle the case where we need non-standard MTU on the boot link (a network
368 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
369 	 * out, we'll try to muddle along.
370 	 */
371 	if (ic_dev_mtu != 0) {
372 		rtnl_lock();
373 		if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0)
374 			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
375 			       ic_dev_mtu, err);
376 		rtnl_unlock();
377 	}
378 	return 0;
379 }
380 
381 static int __init ic_setup_routes(void)
382 {
383 	/* No need to setup device routes, only the default route... */
384 
385 	if (ic_gateway != NONE) {
386 		struct rtentry rm;
387 		int err;
388 
389 		memset(&rm, 0, sizeof(rm));
390 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
391 			pr_err("IP-Config: Gateway not on directly connected network\n");
392 			return -1;
393 		}
394 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
395 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
396 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
397 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
398 		if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) {
399 			pr_err("IP-Config: Cannot add default route (%d)\n",
400 			       err);
401 			return -1;
402 		}
403 	}
404 
405 	return 0;
406 }
407 
408 /*
409  *	Fill in default values for all missing parameters.
410  */
411 
412 static int __init ic_defaults(void)
413 {
414 	/*
415 	 *	At this point we have no userspace running so need not
416 	 *	claim locks on system_utsname
417 	 */
418 
419 	if (!ic_host_name_set)
420 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
421 
422 	if (root_server_addr == NONE)
423 		root_server_addr = ic_servaddr;
424 
425 	if (ic_netmask == NONE) {
426 		if (IN_CLASSA(ntohl(ic_myaddr)))
427 			ic_netmask = htonl(IN_CLASSA_NET);
428 		else if (IN_CLASSB(ntohl(ic_myaddr)))
429 			ic_netmask = htonl(IN_CLASSB_NET);
430 		else if (IN_CLASSC(ntohl(ic_myaddr)))
431 			ic_netmask = htonl(IN_CLASSC_NET);
432 		else if (IN_CLASSE(ntohl(ic_myaddr)))
433 			ic_netmask = htonl(IN_CLASSE_NET);
434 		else {
435 			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
436 			       &ic_myaddr);
437 			return -1;
438 		}
439 		pr_notice("IP-Config: Guessing netmask %pI4\n",
440 			  &ic_netmask);
441 	}
442 
443 	return 0;
444 }
445 
446 /*
447  *	RARP support.
448  */
449 
450 #ifdef IPCONFIG_RARP
451 
452 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
453 
454 static struct packet_type rarp_packet_type __initdata = {
455 	.type =	cpu_to_be16(ETH_P_RARP),
456 	.func =	ic_rarp_recv,
457 };
458 
459 static inline void __init ic_rarp_init(void)
460 {
461 	dev_add_pack(&rarp_packet_type);
462 }
463 
464 static inline void __init ic_rarp_cleanup(void)
465 {
466 	dev_remove_pack(&rarp_packet_type);
467 }
468 
469 /*
470  *  Process received RARP packet.
471  */
472 static int __init
473 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
474 {
475 	struct arphdr *rarp;
476 	unsigned char *rarp_ptr;
477 	__be32 sip, tip;
478 	unsigned char *tha;		/* t for "target" */
479 	struct ic_device *d;
480 
481 	if (!net_eq(dev_net(dev), &init_net))
482 		goto drop;
483 
484 	skb = skb_share_check(skb, GFP_ATOMIC);
485 	if (!skb)
486 		return NET_RX_DROP;
487 
488 	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
489 		goto drop;
490 
491 	/* Basic sanity checks can be done without the lock.  */
492 	rarp = (struct arphdr *)skb_transport_header(skb);
493 
494 	/* If this test doesn't pass, it's not IP, or we should
495 	 * ignore it anyway.
496 	 */
497 	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
498 		goto drop;
499 
500 	/* If it's not a RARP reply, delete it. */
501 	if (rarp->ar_op != htons(ARPOP_RREPLY))
502 		goto drop;
503 
504 	/* If it's not Ethernet, delete it. */
505 	if (rarp->ar_pro != htons(ETH_P_IP))
506 		goto drop;
507 
508 	if (!pskb_may_pull(skb, arp_hdr_len(dev)))
509 		goto drop;
510 
511 	/* OK, it is all there and looks valid, process... */
512 	rarp = (struct arphdr *)skb_transport_header(skb);
513 	rarp_ptr = (unsigned char *) (rarp + 1);
514 
515 	/* One reply at a time, please. */
516 	spin_lock(&ic_recv_lock);
517 
518 	/* If we already have a reply, just drop the packet */
519 	if (ic_got_reply)
520 		goto drop_unlock;
521 
522 	/* Find the ic_device that the packet arrived on */
523 	d = ic_first_dev;
524 	while (d && d->dev != dev)
525 		d = d->next;
526 	if (!d)
527 		goto drop_unlock;	/* should never happen */
528 
529 	/* Extract variable-width fields */
530 	rarp_ptr += dev->addr_len;
531 	memcpy(&sip, rarp_ptr, 4);
532 	rarp_ptr += 4;
533 	tha = rarp_ptr;
534 	rarp_ptr += dev->addr_len;
535 	memcpy(&tip, rarp_ptr, 4);
536 
537 	/* Discard packets which are not meant for us. */
538 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
539 		goto drop_unlock;
540 
541 	/* Discard packets which are not from specified server. */
542 	if (ic_servaddr != NONE && ic_servaddr != sip)
543 		goto drop_unlock;
544 
545 	/* We have a winner! */
546 	ic_dev = d;
547 	if (ic_myaddr == NONE)
548 		ic_myaddr = tip;
549 	ic_servaddr = sip;
550 	ic_addrservaddr = sip;
551 	ic_got_reply = IC_RARP;
552 
553 drop_unlock:
554 	/* Show's over.  Nothing to see here.  */
555 	spin_unlock(&ic_recv_lock);
556 
557 drop:
558 	/* Throw the packet out. */
559 	kfree_skb(skb);
560 	return 0;
561 }
562 
563 
564 /*
565  *  Send RARP request packet over a single interface.
566  */
567 static void __init ic_rarp_send_if(struct ic_device *d)
568 {
569 	struct net_device *dev = d->dev;
570 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
571 		 dev->dev_addr, dev->dev_addr);
572 }
573 #endif
574 
575 /*
576  *  Predefine Nameservers
577  */
578 static inline void __init ic_nameservers_predef(void)
579 {
580 	int i;
581 
582 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
583 		ic_nameservers[i] = NONE;
584 }
585 
586 /* Predefine NTP servers */
587 static inline void __init ic_ntp_servers_predef(void)
588 {
589 	int i;
590 
591 	for (i = 0; i < CONF_NTP_SERVERS_MAX; i++)
592 		ic_ntp_servers[i] = NONE;
593 }
594 
595 /*
596  *	DHCP/BOOTP support.
597  */
598 
599 #ifdef IPCONFIG_BOOTP
600 
601 struct bootp_pkt {		/* BOOTP packet format */
602 	struct iphdr iph;	/* IP header */
603 	struct udphdr udph;	/* UDP header */
604 	u8 op;			/* 1=request, 2=reply */
605 	u8 htype;		/* HW address type */
606 	u8 hlen;		/* HW address length */
607 	u8 hops;		/* Used only by gateways */
608 	__be32 xid;		/* Transaction ID */
609 	__be16 secs;		/* Seconds since we started */
610 	__be16 flags;		/* Just what it says */
611 	__be32 client_ip;		/* Client's IP address if known */
612 	__be32 your_ip;		/* Assigned IP address */
613 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
614 	__be32 relay_ip;		/* IP address of BOOTP relay */
615 	u8 hw_addr[16];		/* Client's HW address */
616 	u8 serv_name[64];	/* Server host name */
617 	u8 boot_file[128];	/* Name of boot file */
618 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
619 };
620 
621 /* packet ops */
622 #define BOOTP_REQUEST	1
623 #define BOOTP_REPLY	2
624 
625 /* DHCP message types */
626 #define DHCPDISCOVER	1
627 #define DHCPOFFER	2
628 #define DHCPREQUEST	3
629 #define DHCPDECLINE	4
630 #define DHCPACK		5
631 #define DHCPNAK		6
632 #define DHCPRELEASE	7
633 #define DHCPINFORM	8
634 
635 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
636 
637 static struct packet_type bootp_packet_type __initdata = {
638 	.type =	cpu_to_be16(ETH_P_IP),
639 	.func =	ic_bootp_recv,
640 };
641 
642 /*
643  *  Initialize DHCP/BOOTP extension fields in the request.
644  */
645 
646 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
647 
648 #ifdef IPCONFIG_DHCP
649 
650 static void __init
651 ic_dhcp_init_options(u8 *options, struct ic_device *d)
652 {
653 	u8 mt = ((ic_servaddr == NONE)
654 		 ? DHCPDISCOVER : DHCPREQUEST);
655 	u8 *e = options;
656 	int len;
657 
658 	pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
659 
660 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
661 	e += 4;
662 
663 	*e++ = 53;		/* DHCP message type */
664 	*e++ = 1;
665 	*e++ = mt;
666 
667 	if (mt == DHCPREQUEST) {
668 		*e++ = 54;	/* Server ID (IP address) */
669 		*e++ = 4;
670 		memcpy(e, &ic_servaddr, 4);
671 		e += 4;
672 
673 		*e++ = 50;	/* Requested IP address */
674 		*e++ = 4;
675 		memcpy(e, &ic_myaddr, 4);
676 		e += 4;
677 	}
678 
679 	/* always? */
680 	{
681 		static const u8 ic_req_params[] = {
682 			1,	/* Subnet mask */
683 			3,	/* Default gateway */
684 			6,	/* DNS server */
685 			12,	/* Host name */
686 			15,	/* Domain name */
687 			17,	/* Boot path */
688 			26,	/* MTU */
689 			40,	/* NIS domain name */
690 			42,	/* NTP servers */
691 		};
692 
693 		*e++ = 55;	/* Parameter request list */
694 		*e++ = sizeof(ic_req_params);
695 		memcpy(e, ic_req_params, sizeof(ic_req_params));
696 		e += sizeof(ic_req_params);
697 
698 		if (ic_host_name_set) {
699 			*e++ = 12;	/* host-name */
700 			len = strlen(utsname()->nodename);
701 			*e++ = len;
702 			memcpy(e, utsname()->nodename, len);
703 			e += len;
704 		}
705 		if (*vendor_class_identifier) {
706 			pr_info("DHCP: sending class identifier \"%s\"\n",
707 				vendor_class_identifier);
708 			*e++ = 60;	/* Class-identifier */
709 			len = strlen(vendor_class_identifier);
710 			*e++ = len;
711 			memcpy(e, vendor_class_identifier, len);
712 			e += len;
713 		}
714 		len = strlen(dhcp_client_identifier + 1);
715 		/* the minimum length of identifier is 2, include 1 byte type,
716 		 * and can not be larger than the length of options
717 		 */
718 		if (len >= 1 && len < 312 - (e - options) - 1) {
719 			*e++ = 61;
720 			*e++ = len + 1;
721 			memcpy(e, dhcp_client_identifier, len + 1);
722 			e += len + 1;
723 		}
724 	}
725 
726 	*e++ = 255;	/* End of the list */
727 }
728 
729 #endif /* IPCONFIG_DHCP */
730 
731 static void __init ic_bootp_init_ext(u8 *e)
732 {
733 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
734 	e += 4;
735 	*e++ = 1;		/* Subnet mask request */
736 	*e++ = 4;
737 	e += 4;
738 	*e++ = 3;		/* Default gateway request */
739 	*e++ = 4;
740 	e += 4;
741 #if CONF_NAMESERVERS_MAX > 0
742 	*e++ = 6;		/* (DNS) name server request */
743 	*e++ = 4 * CONF_NAMESERVERS_MAX;
744 	e += 4 * CONF_NAMESERVERS_MAX;
745 #endif
746 	*e++ = 12;		/* Host name request */
747 	*e++ = 32;
748 	e += 32;
749 	*e++ = 40;		/* NIS Domain name request */
750 	*e++ = 32;
751 	e += 32;
752 	*e++ = 17;		/* Boot path */
753 	*e++ = 40;
754 	e += 40;
755 
756 	*e++ = 57;		/* set extension buffer size for reply */
757 	*e++ = 2;
758 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
759 	*e++ = 150;
760 
761 	*e++ = 255;		/* End of the list */
762 }
763 
764 
765 /*
766  *  Initialize the DHCP/BOOTP mechanism.
767  */
768 static inline void __init ic_bootp_init(void)
769 {
770 	/* Re-initialise all name servers and NTP servers to NONE, in case any
771 	 * were set via the "ip=" or "nfsaddrs=" kernel command line parameters:
772 	 * any IP addresses specified there will already have been decoded but
773 	 * are no longer needed
774 	 */
775 	ic_nameservers_predef();
776 	ic_ntp_servers_predef();
777 
778 	dev_add_pack(&bootp_packet_type);
779 }
780 
781 
782 /*
783  *  DHCP/BOOTP cleanup.
784  */
785 static inline void __init ic_bootp_cleanup(void)
786 {
787 	dev_remove_pack(&bootp_packet_type);
788 }
789 
790 
791 /*
792  *  Send DHCP/BOOTP request to single interface.
793  */
794 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
795 {
796 	struct net_device *dev = d->dev;
797 	struct sk_buff *skb;
798 	struct bootp_pkt *b;
799 	struct iphdr *h;
800 	int hlen = LL_RESERVED_SPACE(dev);
801 	int tlen = dev->needed_tailroom;
802 
803 	/* Allocate packet */
804 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
805 			GFP_KERNEL);
806 	if (!skb)
807 		return;
808 	skb_reserve(skb, hlen);
809 	b = skb_put_zero(skb, 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 		pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
837 			dev->name);
838 		b->htype = dev->type; /* can cause undefined behavior */
839 	}
840 
841 	/* server_ip and your_ip address are both already zero per RFC2131 */
842 	b->hlen = dev->addr_len;
843 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
844 	b->secs = htons(jiffies_diff / HZ);
845 	b->xid = d->xid;
846 
847 	/* add DHCP options or BOOTP extensions */
848 #ifdef IPCONFIG_DHCP
849 	if (ic_proto_enabled & IC_USE_DHCP)
850 		ic_dhcp_init_options(b->exten, d);
851 	else
852 #endif
853 		ic_bootp_init_ext(b->exten);
854 
855 	/* Chain packet down the line... */
856 	skb->dev = dev;
857 	skb->protocol = htons(ETH_P_IP);
858 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
859 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
860 		kfree_skb(skb);
861 		printk("E");
862 		return;
863 	}
864 
865 	if (dev_queue_xmit(skb) < 0)
866 		printk("E");
867 }
868 
869 
870 /*
871  *  Copy BOOTP-supplied string if not already set.
872  */
873 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
874 {
875 	if (!len)
876 		return 0;
877 	if (len > max-1)
878 		len = max-1;
879 	memcpy(dest, src, len);
880 	dest[len] = '\0';
881 	return 1;
882 }
883 
884 
885 /*
886  *  Process BOOTP extensions.
887  */
888 static void __init ic_do_bootp_ext(u8 *ext)
889 {
890 	u8 servers;
891 	int i;
892 	__be16 mtu;
893 
894 	u8 *c;
895 
896 	pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
897 	for (c=ext+2; c<ext+2+ext[1]; c++)
898 		pr_debug(" %02x", *c);
899 	pr_debug("\n");
900 
901 	switch (*ext++) {
902 	case 1:		/* Subnet mask */
903 		if (ic_netmask == NONE)
904 			memcpy(&ic_netmask, ext+1, 4);
905 		break;
906 	case 3:		/* Default gateway */
907 		if (ic_gateway == NONE)
908 			memcpy(&ic_gateway, ext+1, 4);
909 		break;
910 	case 6:		/* DNS server */
911 		servers= *ext/4;
912 		if (servers > CONF_NAMESERVERS_MAX)
913 			servers = CONF_NAMESERVERS_MAX;
914 		for (i = 0; i < servers; i++) {
915 			if (ic_nameservers[i] == NONE)
916 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
917 		}
918 		break;
919 	case 12:	/* Host name */
920 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
921 				__NEW_UTS_LEN);
922 		ic_host_name_set = 1;
923 		break;
924 	case 15:	/* Domain name (DNS) */
925 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
926 		break;
927 	case 17:	/* Root path */
928 		if (!root_server_path[0])
929 			ic_bootp_string(root_server_path, ext+1, *ext,
930 					sizeof(root_server_path));
931 		break;
932 	case 26:	/* Interface MTU */
933 		memcpy(&mtu, ext+1, sizeof(mtu));
934 		ic_dev_mtu = ntohs(mtu);
935 		break;
936 	case 40:	/* NIS Domain name (_not_ DNS) */
937 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
938 				__NEW_UTS_LEN);
939 		break;
940 	case 42:	/* NTP servers */
941 		servers = *ext / 4;
942 		if (servers > CONF_NTP_SERVERS_MAX)
943 			servers = CONF_NTP_SERVERS_MAX;
944 		for (i = 0; i < servers; i++) {
945 			if (ic_ntp_servers[i] == NONE)
946 				memcpy(&ic_ntp_servers[i], ext+1+4*i, 4);
947 		}
948 		break;
949 	}
950 }
951 
952 
953 /*
954  *  Receive BOOTP reply.
955  */
956 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
957 {
958 	struct bootp_pkt *b;
959 	struct iphdr *h;
960 	struct ic_device *d;
961 	int len, ext_len;
962 
963 	if (!net_eq(dev_net(dev), &init_net))
964 		goto drop;
965 
966 	/* Perform verifications before taking the lock.  */
967 	if (skb->pkt_type == PACKET_OTHERHOST)
968 		goto drop;
969 
970 	skb = skb_share_check(skb, GFP_ATOMIC);
971 	if (!skb)
972 		return NET_RX_DROP;
973 
974 	if (!pskb_may_pull(skb,
975 			   sizeof(struct iphdr) +
976 			   sizeof(struct udphdr)))
977 		goto drop;
978 
979 	b = (struct bootp_pkt *)skb_network_header(skb);
980 	h = &b->iph;
981 
982 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
983 		goto drop;
984 
985 	/* Fragments are not supported */
986 	if (ip_is_fragment(h)) {
987 		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
988 		goto drop;
989 	}
990 
991 	if (skb->len < ntohs(h->tot_len))
992 		goto drop;
993 
994 	if (ip_fast_csum((char *) h, h->ihl))
995 		goto drop;
996 
997 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
998 		goto drop;
999 
1000 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1001 		goto drop;
1002 
1003 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
1004 	ext_len = len - (sizeof(*b) -
1005 			 sizeof(struct iphdr) -
1006 			 sizeof(struct udphdr) -
1007 			 sizeof(b->exten));
1008 	if (ext_len < 0)
1009 		goto drop;
1010 
1011 	/* Ok the front looks good, make sure we can get at the rest.  */
1012 	if (!pskb_may_pull(skb, skb->len))
1013 		goto drop;
1014 
1015 	b = (struct bootp_pkt *)skb_network_header(skb);
1016 	h = &b->iph;
1017 
1018 	/* One reply at a time, please. */
1019 	spin_lock(&ic_recv_lock);
1020 
1021 	/* If we already have a reply, just drop the packet */
1022 	if (ic_got_reply)
1023 		goto drop_unlock;
1024 
1025 	/* Find the ic_device that the packet arrived on */
1026 	d = ic_first_dev;
1027 	while (d && d->dev != dev)
1028 		d = d->next;
1029 	if (!d)
1030 		goto drop_unlock;  /* should never happen */
1031 
1032 	/* Is it a reply to our BOOTP request? */
1033 	if (b->op != BOOTP_REPLY ||
1034 	    b->xid != d->xid) {
1035 		net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1036 				    d->dev->name, b->op, b->xid);
1037 		goto drop_unlock;
1038 	}
1039 
1040 	/* Parse extensions */
1041 	if (ext_len >= 4 &&
1042 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1043 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1044 		u8 *ext;
1045 
1046 #ifdef IPCONFIG_DHCP
1047 		if (ic_proto_enabled & IC_USE_DHCP) {
1048 			__be32 server_id = NONE;
1049 			int mt = 0;
1050 
1051 			ext = &b->exten[4];
1052 			while (ext < end && *ext != 0xff) {
1053 				u8 *opt = ext++;
1054 				if (*opt == 0)	/* Padding */
1055 					continue;
1056 				ext += *ext + 1;
1057 				if (ext >= end)
1058 					break;
1059 				switch (*opt) {
1060 				case 53:	/* Message type */
1061 					if (opt[1])
1062 						mt = opt[2];
1063 					break;
1064 				case 54:	/* Server ID (IP address) */
1065 					if (opt[1] >= 4)
1066 						memcpy(&server_id, opt + 2, 4);
1067 					break;
1068 				}
1069 			}
1070 
1071 			pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
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 				pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1085 					 &ic_myaddr, &b->iph.saddr);
1086 				/* The DHCP indicated server address takes
1087 				 * precedence over the bootp header one if
1088 				 * they are different.
1089 				 */
1090 				if ((server_id != NONE) &&
1091 				    (b->server_ip != server_id))
1092 					b->server_ip = ic_servaddr;
1093 				break;
1094 
1095 			case DHCPACK:
1096 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1097 					goto drop_unlock;
1098 
1099 				/* Yeah! */
1100 				break;
1101 
1102 			default:
1103 				/* Urque.  Forget it*/
1104 				ic_myaddr = NONE;
1105 				ic_servaddr = NONE;
1106 				goto drop_unlock;
1107 			}
1108 
1109 			ic_dhcp_msgtype = mt;
1110 
1111 		}
1112 #endif /* IPCONFIG_DHCP */
1113 
1114 		ext = &b->exten[4];
1115 		while (ext < end && *ext != 0xff) {
1116 			u8 *opt = ext++;
1117 			if (*opt == 0)	/* Padding */
1118 				continue;
1119 			ext += *ext + 1;
1120 			if (ext < end)
1121 				ic_do_bootp_ext(opt);
1122 		}
1123 	}
1124 
1125 	/* We have a winner! */
1126 	ic_dev = d;
1127 	ic_myaddr = b->your_ip;
1128 	ic_servaddr = b->server_ip;
1129 	ic_addrservaddr = b->iph.saddr;
1130 	if (ic_gateway == NONE && b->relay_ip)
1131 		ic_gateway = b->relay_ip;
1132 	if (ic_nameservers[0] == NONE)
1133 		ic_nameservers[0] = ic_servaddr;
1134 	ic_got_reply = IC_BOOTP;
1135 
1136 drop_unlock:
1137 	/* Show's over.  Nothing to see here.  */
1138 	spin_unlock(&ic_recv_lock);
1139 
1140 drop:
1141 	/* Throw the packet out. */
1142 	kfree_skb(skb);
1143 
1144 	return 0;
1145 }
1146 
1147 
1148 #endif
1149 
1150 
1151 /*
1152  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1153  */
1154 
1155 #ifdef IPCONFIG_DYNAMIC
1156 
1157 static int __init ic_dynamic(void)
1158 {
1159 	int retries;
1160 	struct ic_device *d;
1161 	unsigned long start_jiffies, timeout, jiff;
1162 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1163 	int do_rarp = ic_proto_have_if & IC_RARP;
1164 
1165 	/*
1166 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1167 	 * This routine gets only called when some pieces of information
1168 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1169 	 */
1170 	if (!ic_proto_enabled) {
1171 		pr_err("IP-Config: Incomplete network configuration information\n");
1172 		return -1;
1173 	}
1174 
1175 #ifdef IPCONFIG_BOOTP
1176 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1177 		pr_err("DHCP/BOOTP: No suitable device found\n");
1178 #endif
1179 #ifdef IPCONFIG_RARP
1180 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1181 		pr_err("RARP: No suitable device found\n");
1182 #endif
1183 
1184 	if (!ic_proto_have_if)
1185 		/* Error message already printed */
1186 		return -1;
1187 
1188 	/*
1189 	 * Setup protocols
1190 	 */
1191 #ifdef IPCONFIG_BOOTP
1192 	if (do_bootp)
1193 		ic_bootp_init();
1194 #endif
1195 #ifdef IPCONFIG_RARP
1196 	if (do_rarp)
1197 		ic_rarp_init();
1198 #endif
1199 
1200 	/*
1201 	 * Send requests and wait, until we get an answer. This loop
1202 	 * seems to be a terrible waste of CPU time, but actually there is
1203 	 * only one process running at all, so we don't need to use any
1204 	 * scheduler functions.
1205 	 * [Actually we could now, but the nothing else running note still
1206 	 *  applies.. - AC]
1207 	 */
1208 	pr_notice("Sending %s%s%s requests .",
1209 		  do_bootp
1210 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1211 		  (do_bootp && do_rarp) ? " and " : "",
1212 		  do_rarp ? "RARP" : "");
1213 
1214 	start_jiffies = jiffies;
1215 	d = ic_first_dev;
1216 	retries = CONF_SEND_RETRIES;
1217 	get_random_bytes(&timeout, sizeof(timeout));
1218 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1219 	for (;;) {
1220 #ifdef IPCONFIG_BOOTP
1221 		if (do_bootp && (d->able & IC_BOOTP))
1222 			ic_bootp_send_if(d, jiffies - start_jiffies);
1223 #endif
1224 #ifdef IPCONFIG_RARP
1225 		if (do_rarp && (d->able & IC_RARP))
1226 			ic_rarp_send_if(d);
1227 #endif
1228 
1229 		if (!d->next) {
1230 			jiff = jiffies + timeout;
1231 			while (time_before(jiffies, jiff) && !ic_got_reply)
1232 				schedule_timeout_uninterruptible(1);
1233 		}
1234 #ifdef IPCONFIG_DHCP
1235 		/* DHCP isn't done until we get a DHCPACK. */
1236 		if ((ic_got_reply & IC_BOOTP) &&
1237 		    (ic_proto_enabled & IC_USE_DHCP) &&
1238 		    ic_dhcp_msgtype != DHCPACK) {
1239 			ic_got_reply = 0;
1240 			/* continue on device that got the reply */
1241 			d = ic_dev;
1242 			pr_cont(",");
1243 			continue;
1244 		}
1245 #endif /* IPCONFIG_DHCP */
1246 
1247 		if (ic_got_reply) {
1248 			pr_cont(" OK\n");
1249 			break;
1250 		}
1251 
1252 		if ((d = d->next))
1253 			continue;
1254 
1255 		if (! --retries) {
1256 			pr_cont(" timed out!\n");
1257 			break;
1258 		}
1259 
1260 		d = ic_first_dev;
1261 
1262 		timeout = timeout CONF_TIMEOUT_MULT;
1263 		if (timeout > CONF_TIMEOUT_MAX)
1264 			timeout = CONF_TIMEOUT_MAX;
1265 
1266 		pr_cont(".");
1267 	}
1268 
1269 #ifdef IPCONFIG_BOOTP
1270 	if (do_bootp)
1271 		ic_bootp_cleanup();
1272 #endif
1273 #ifdef IPCONFIG_RARP
1274 	if (do_rarp)
1275 		ic_rarp_cleanup();
1276 #endif
1277 
1278 	if (!ic_got_reply) {
1279 		ic_myaddr = NONE;
1280 		return -1;
1281 	}
1282 
1283 	pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1284 		((ic_got_reply & IC_RARP) ? "RARP"
1285 		: (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1286 		&ic_addrservaddr, &ic_myaddr);
1287 
1288 	return 0;
1289 }
1290 
1291 #endif /* IPCONFIG_DYNAMIC */
1292 
1293 #ifdef CONFIG_PROC_FS
1294 /* proc_dir_entry for /proc/net/ipconfig */
1295 static struct proc_dir_entry *ipconfig_dir;
1296 
1297 /* Name servers: */
1298 static int pnp_seq_show(struct seq_file *seq, void *v)
1299 {
1300 	int i;
1301 
1302 	if (ic_proto_used & IC_PROTO)
1303 		seq_printf(seq, "#PROTO: %s\n",
1304 			   (ic_proto_used & IC_RARP) ? "RARP"
1305 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1306 	else
1307 		seq_puts(seq, "#MANUAL\n");
1308 
1309 	if (ic_domain[0])
1310 		seq_printf(seq,
1311 			   "domain %s\n", ic_domain);
1312 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1313 		if (ic_nameservers[i] != NONE)
1314 			seq_printf(seq, "nameserver %pI4\n",
1315 				   &ic_nameservers[i]);
1316 	}
1317 	if (ic_servaddr != NONE)
1318 		seq_printf(seq, "bootserver %pI4\n",
1319 			   &ic_servaddr);
1320 	return 0;
1321 }
1322 
1323 /* Create the /proc/net/ipconfig directory */
1324 static int __init ipconfig_proc_net_init(void)
1325 {
1326 	ipconfig_dir = proc_net_mkdir(&init_net, "ipconfig", init_net.proc_net);
1327 	if (!ipconfig_dir)
1328 		return -ENOMEM;
1329 
1330 	return 0;
1331 }
1332 
1333 /* Create a new file under /proc/net/ipconfig */
1334 static int ipconfig_proc_net_create(const char *name,
1335 				    const struct file_operations *fops)
1336 {
1337 	char *pname;
1338 	struct proc_dir_entry *p;
1339 
1340 	if (!ipconfig_dir)
1341 		return -ENOMEM;
1342 
1343 	pname = kasprintf(GFP_KERNEL, "%s%s", "ipconfig/", name);
1344 	if (!pname)
1345 		return -ENOMEM;
1346 
1347 	p = proc_create(pname, 0444, init_net.proc_net, fops);
1348 	kfree(pname);
1349 	if (!p)
1350 		return -ENOMEM;
1351 
1352 	return 0;
1353 }
1354 
1355 /* Write NTP server IP addresses to /proc/net/ipconfig/ntp_servers */
1356 static int ntp_servers_seq_show(struct seq_file *seq, void *v)
1357 {
1358 	int i;
1359 
1360 	for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1361 		if (ic_ntp_servers[i] != NONE)
1362 			seq_printf(seq, "%pI4\n", &ic_ntp_servers[i]);
1363 	}
1364 	return 0;
1365 }
1366 DEFINE_SHOW_ATTRIBUTE(ntp_servers_seq);
1367 #endif /* CONFIG_PROC_FS */
1368 
1369 /*
1370  *  Extract IP address from the parameter string if needed. Note that we
1371  *  need to have root_server_addr set _before_ IPConfig gets called as it
1372  *  can override it.
1373  */
1374 __be32 __init root_nfs_parse_addr(char *name)
1375 {
1376 	__be32 addr;
1377 	int octets = 0;
1378 	char *cp, *cq;
1379 
1380 	cp = cq = name;
1381 	while (octets < 4) {
1382 		while (*cp >= '0' && *cp <= '9')
1383 			cp++;
1384 		if (cp == cq || cp - cq > 3)
1385 			break;
1386 		if (*cp == '.' || octets == 3)
1387 			octets++;
1388 		if (octets < 4)
1389 			cp++;
1390 		cq = cp;
1391 	}
1392 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1393 		if (*cp == ':')
1394 			*cp++ = '\0';
1395 		addr = in_aton(name);
1396 		memmove(name, cp, strlen(cp) + 1);
1397 	} else
1398 		addr = NONE;
1399 
1400 	return addr;
1401 }
1402 
1403 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1404 
1405 static int __init wait_for_devices(void)
1406 {
1407 	int i;
1408 
1409 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1410 		struct net_device *dev;
1411 		int found = 0;
1412 
1413 		rtnl_lock();
1414 		for_each_netdev(&init_net, dev) {
1415 			if (ic_is_init_dev(dev)) {
1416 				found = 1;
1417 				break;
1418 			}
1419 		}
1420 		rtnl_unlock();
1421 		if (found)
1422 			return 0;
1423 		ssleep(1);
1424 	}
1425 	return -ENODEV;
1426 }
1427 
1428 /*
1429  *	IP Autoconfig dispatcher.
1430  */
1431 
1432 static int __init ip_auto_config(void)
1433 {
1434 	__be32 addr;
1435 #ifdef IPCONFIG_DYNAMIC
1436 	int retries = CONF_OPEN_RETRIES;
1437 #endif
1438 	int err;
1439 	unsigned int i;
1440 
1441 	/* Initialise all name servers and NTP servers to NONE (but only if the
1442 	 * "ip=" or "nfsaddrs=" kernel command line parameters weren't decoded,
1443 	 * otherwise we'll overwrite the IP addresses specified there)
1444 	 */
1445 	if (ic_set_manually == 0) {
1446 		ic_nameservers_predef();
1447 		ic_ntp_servers_predef();
1448 	}
1449 
1450 #ifdef CONFIG_PROC_FS
1451 	proc_create_single("pnp", 0444, init_net.proc_net, pnp_seq_show);
1452 
1453 	if (ipconfig_proc_net_init() == 0)
1454 		ipconfig_proc_net_create("ntp_servers", &ntp_servers_seq_fops);
1455 #endif /* CONFIG_PROC_FS */
1456 
1457 	if (!ic_enable)
1458 		return 0;
1459 
1460 	pr_debug("IP-Config: Entered.\n");
1461 #ifdef IPCONFIG_DYNAMIC
1462  try_try_again:
1463 #endif
1464 	/* Wait for devices to appear */
1465 	err = wait_for_devices();
1466 	if (err)
1467 		return err;
1468 
1469 	/* Setup all network devices */
1470 	err = ic_open_devs();
1471 	if (err)
1472 		return err;
1473 
1474 	/* Give drivers a chance to settle */
1475 	msleep(CONF_POST_OPEN);
1476 
1477 	/*
1478 	 * If the config information is insufficient (e.g., our IP address or
1479 	 * IP address of the boot server is missing or we have multiple network
1480 	 * interfaces and no default was set), use BOOTP or RARP to get the
1481 	 * missing values.
1482 	 */
1483 	if (ic_myaddr == NONE ||
1484 #ifdef CONFIG_ROOT_NFS
1485 	    (root_server_addr == NONE &&
1486 	     ic_servaddr == NONE &&
1487 	     ROOT_DEV == Root_NFS) ||
1488 #endif
1489 	    ic_first_dev->next) {
1490 #ifdef IPCONFIG_DYNAMIC
1491 		if (ic_dynamic() < 0) {
1492 			ic_close_devs();
1493 
1494 			/*
1495 			 * I don't know why, but sometimes the
1496 			 * eepro100 driver (at least) gets upset and
1497 			 * doesn't work the first time it's opened.
1498 			 * But then if you close it and reopen it, it
1499 			 * works just fine.  So we need to try that at
1500 			 * least once before giving up.
1501 			 *
1502 			 * Also, if the root will be NFS-mounted, we
1503 			 * have nowhere to go if DHCP fails.  So we
1504 			 * just have to keep trying forever.
1505 			 *
1506 			 * 				-- Chip
1507 			 */
1508 #ifdef CONFIG_ROOT_NFS
1509 			if (ROOT_DEV ==  Root_NFS) {
1510 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1511 				goto try_try_again;
1512 			}
1513 #endif
1514 
1515 			if (--retries) {
1516 				pr_err("IP-Config: Reopening network devices...\n");
1517 				goto try_try_again;
1518 			}
1519 
1520 			/* Oh, well.  At least we tried. */
1521 			pr_err("IP-Config: Auto-configuration of network failed\n");
1522 			return -1;
1523 		}
1524 #else /* !DYNAMIC */
1525 		pr_err("IP-Config: Incomplete network configuration information\n");
1526 		ic_close_devs();
1527 		return -1;
1528 #endif /* IPCONFIG_DYNAMIC */
1529 	} else {
1530 		/* Device selected manually or only one device -> use it */
1531 		ic_dev = ic_first_dev;
1532 	}
1533 
1534 	addr = root_nfs_parse_addr(root_server_path);
1535 	if (root_server_addr == NONE)
1536 		root_server_addr = addr;
1537 
1538 	/*
1539 	 * Use defaults wherever applicable.
1540 	 */
1541 	if (ic_defaults() < 0)
1542 		return -1;
1543 
1544 	/*
1545 	 * Record which protocol was actually used.
1546 	 */
1547 #ifdef IPCONFIG_DYNAMIC
1548 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1549 #endif
1550 
1551 #ifndef IPCONFIG_SILENT
1552 	/*
1553 	 * Clue in the operator.
1554 	 */
1555 	pr_info("IP-Config: Complete:\n");
1556 
1557 	pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1558 		ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1559 		&ic_myaddr, &ic_netmask, &ic_gateway);
1560 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1561 		utsname()->nodename, ic_domain, utsname()->domainname);
1562 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1563 		&ic_servaddr, &root_server_addr, root_server_path);
1564 	if (ic_dev_mtu)
1565 		pr_cont(", mtu=%d", ic_dev_mtu);
1566 	/* Name servers (if any): */
1567 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1568 		if (ic_nameservers[i] != NONE) {
1569 			if (i == 0)
1570 				pr_info("     nameserver%u=%pI4",
1571 					i, &ic_nameservers[i]);
1572 			else
1573 				pr_cont(", nameserver%u=%pI4",
1574 					i, &ic_nameservers[i]);
1575 		}
1576 		if (i + 1 == CONF_NAMESERVERS_MAX)
1577 			pr_cont("\n");
1578 	}
1579 	/* NTP servers (if any): */
1580 	for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1581 		if (ic_ntp_servers[i] != NONE) {
1582 			if (i == 0)
1583 				pr_info("     ntpserver%u=%pI4",
1584 					i, &ic_ntp_servers[i]);
1585 			else
1586 				pr_cont(", ntpserver%u=%pI4",
1587 					i, &ic_ntp_servers[i]);
1588 		}
1589 		if (i + 1 == CONF_NTP_SERVERS_MAX)
1590 			pr_cont("\n");
1591 	}
1592 #endif /* !SILENT */
1593 
1594 	/*
1595 	 * Close all network devices except the device we've
1596 	 * autoconfigured and set up routes.
1597 	 */
1598 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1599 		err = -1;
1600 	else
1601 		err = 0;
1602 
1603 	ic_close_devs();
1604 
1605 	return err;
1606 }
1607 
1608 late_initcall(ip_auto_config);
1609 
1610 
1611 /*
1612  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1613  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1614  */
1615 static int __init ic_proto_name(char *name)
1616 {
1617 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1618 		return 1;
1619 	}
1620 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1621 		return 0;
1622 	}
1623 #ifdef CONFIG_IP_PNP_DHCP
1624 	else if (!strncmp(name, "dhcp", 4)) {
1625 		char *client_id;
1626 
1627 		ic_proto_enabled &= ~IC_RARP;
1628 		client_id = strstr(name, "dhcp,");
1629 		if (client_id) {
1630 			char *v;
1631 
1632 			client_id = client_id + 5;
1633 			v = strchr(client_id, ',');
1634 			if (!v)
1635 				return 1;
1636 			*v = 0;
1637 			if (kstrtou8(client_id, 0, dhcp_client_identifier))
1638 				pr_debug("DHCP: Invalid client identifier type\n");
1639 			strncpy(dhcp_client_identifier + 1, v + 1, 251);
1640 			*v = ',';
1641 		}
1642 		return 1;
1643 	}
1644 #endif
1645 #ifdef CONFIG_IP_PNP_BOOTP
1646 	else if (!strcmp(name, "bootp")) {
1647 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1648 		return 1;
1649 	}
1650 #endif
1651 #ifdef CONFIG_IP_PNP_RARP
1652 	else if (!strcmp(name, "rarp")) {
1653 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1654 		return 1;
1655 	}
1656 #endif
1657 #ifdef IPCONFIG_DYNAMIC
1658 	else if (!strcmp(name, "both")) {
1659 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1660 		return 1;
1661 	}
1662 #endif
1663 	return 0;
1664 }
1665 
1666 static int __init ip_auto_config_setup(char *addrs)
1667 {
1668 	char *cp, *ip, *dp;
1669 	int num = 0;
1670 
1671 	ic_set_manually = 1;
1672 	ic_enable = 1;
1673 
1674 	/*
1675 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1676 	 * and skip the below static IP processing.
1677 	 */
1678 	if (ic_proto_name(addrs))
1679 		return 1;
1680 
1681 	/* If no static IP is given, turn off autoconfig and bail.  */
1682 	if (*addrs == 0 ||
1683 	    strcmp(addrs, "off") == 0 ||
1684 	    strcmp(addrs, "none") == 0) {
1685 		ic_enable = 0;
1686 		return 1;
1687 	}
1688 
1689 	/* Initialise all name servers and NTP servers to NONE */
1690 	ic_nameservers_predef();
1691 	ic_ntp_servers_predef();
1692 
1693 	/* Parse string for static IP assignment.  */
1694 	ip = addrs;
1695 	while (ip && *ip) {
1696 		if ((cp = strchr(ip, ':')))
1697 			*cp++ = '\0';
1698 		if (strlen(ip) > 0) {
1699 			pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1700 			switch (num) {
1701 			case 0:
1702 				if ((ic_myaddr = in_aton(ip)) == ANY)
1703 					ic_myaddr = NONE;
1704 				break;
1705 			case 1:
1706 				if ((ic_servaddr = in_aton(ip)) == ANY)
1707 					ic_servaddr = NONE;
1708 				break;
1709 			case 2:
1710 				if ((ic_gateway = in_aton(ip)) == ANY)
1711 					ic_gateway = NONE;
1712 				break;
1713 			case 3:
1714 				if ((ic_netmask = in_aton(ip)) == ANY)
1715 					ic_netmask = NONE;
1716 				break;
1717 			case 4:
1718 				if ((dp = strchr(ip, '.'))) {
1719 					*dp++ = '\0';
1720 					strlcpy(utsname()->domainname, dp,
1721 						sizeof(utsname()->domainname));
1722 				}
1723 				strlcpy(utsname()->nodename, ip,
1724 					sizeof(utsname()->nodename));
1725 				ic_host_name_set = 1;
1726 				break;
1727 			case 5:
1728 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1729 				break;
1730 			case 6:
1731 				if (ic_proto_name(ip) == 0 &&
1732 				    ic_myaddr == NONE) {
1733 					ic_enable = 0;
1734 				}
1735 				break;
1736 			case 7:
1737 				if (CONF_NAMESERVERS_MAX >= 1) {
1738 					ic_nameservers[0] = in_aton(ip);
1739 					if (ic_nameservers[0] == ANY)
1740 						ic_nameservers[0] = NONE;
1741 				}
1742 				break;
1743 			case 8:
1744 				if (CONF_NAMESERVERS_MAX >= 2) {
1745 					ic_nameservers[1] = in_aton(ip);
1746 					if (ic_nameservers[1] == ANY)
1747 						ic_nameservers[1] = NONE;
1748 				}
1749 				break;
1750 			case 9:
1751 				if (CONF_NTP_SERVERS_MAX >= 1) {
1752 					ic_ntp_servers[0] = in_aton(ip);
1753 					if (ic_ntp_servers[0] == ANY)
1754 						ic_ntp_servers[0] = NONE;
1755 				}
1756 				break;
1757 			}
1758 		}
1759 		ip = cp;
1760 		num++;
1761 	}
1762 
1763 	return 1;
1764 }
1765 __setup("ip=", ip_auto_config_setup);
1766 
1767 static int __init nfsaddrs_config_setup(char *addrs)
1768 {
1769 	return ip_auto_config_setup(addrs);
1770 }
1771 __setup("nfsaddrs=", nfsaddrs_config_setup);
1772 
1773 static int __init vendor_class_identifier_setup(char *addrs)
1774 {
1775 	if (strlcpy(vendor_class_identifier, addrs,
1776 		    sizeof(vendor_class_identifier))
1777 	    >= sizeof(vendor_class_identifier))
1778 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1779 			vendor_class_identifier);
1780 	return 1;
1781 }
1782 __setup("dhcpclass=", vendor_class_identifier_setup);
1783