xref: /linux/net/ipv4/ipconfig.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /*
2  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
3  *  user-supplied information to configure own IP address and routes.
4  *
5  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
6  *
7  *  Derived from network configuration code in fs/nfs/nfsroot.c,
8  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
9  *
10  *  BOOTP rewritten to construct and analyse packets itself instead
11  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
12  *					     -- MJ, December 1998
13  *
14  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
15  *  initialization scheme.
16  *	- Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
17  *
18  *  DHCP support added.  To users this looks like a whole separate
19  *  protocol, but we know it's just a bag on the side of BOOTP.
20  *		-- Chip Salzenberg <chip@valinux.com>, May 2000
21  *
22  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
23  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
24  *
25  *  Merged changes from 2.2.19 into 2.4.3
26  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
27  *
28  *  Multiple Nameservers in /proc/net/pnp
29  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
30  */
31 
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/kernel.h>
35 #include <linux/jiffies.h>
36 #include <linux/random.h>
37 #include <linux/init.h>
38 #include <linux/utsname.h>
39 #include <linux/in.h>
40 #include <linux/if.h>
41 #include <linux/inet.h>
42 #include <linux/inetdevice.h>
43 #include <linux/netdevice.h>
44 #include <linux/if_arp.h>
45 #include <linux/skbuff.h>
46 #include <linux/ip.h>
47 #include <linux/socket.h>
48 #include <linux/route.h>
49 #include <linux/udp.h>
50 #include <linux/proc_fs.h>
51 #include <linux/seq_file.h>
52 #include <linux/major.h>
53 #include <linux/root_dev.h>
54 #include <linux/delay.h>
55 #include <linux/nfs_fs.h>
56 #include <linux/slab.h>
57 #include <linux/export.h>
58 #include <net/net_namespace.h>
59 #include <net/arp.h>
60 #include <net/ip.h>
61 #include <net/ipconfig.h>
62 #include <net/route.h>
63 
64 #include <asm/uaccess.h>
65 #include <net/checksum.h>
66 #include <asm/processor.h>
67 
68 /* Define this to allow debugging output */
69 #undef IPCONFIG_DEBUG
70 
71 #ifdef IPCONFIG_DEBUG
72 #define DBG(x) printk x
73 #else
74 #define DBG(x) do { } while(0)
75 #endif
76 
77 #if defined(CONFIG_IP_PNP_DHCP)
78 #define IPCONFIG_DHCP
79 #endif
80 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
81 #define IPCONFIG_BOOTP
82 #endif
83 #if defined(CONFIG_IP_PNP_RARP)
84 #define IPCONFIG_RARP
85 #endif
86 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
87 #define IPCONFIG_DYNAMIC
88 #endif
89 
90 /* Define the friendly delay before and after opening net devices */
91 #define CONF_POST_OPEN		10	/* After opening: 10 msecs */
92 #define CONF_CARRIER_TIMEOUT	120000	/* Wait for carrier timeout */
93 
94 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
95 #define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
96 #define CONF_SEND_RETRIES 	6	/* Send six requests per open */
97 #define CONF_INTER_TIMEOUT	(HZ/2)	/* Inter-device timeout: 1/2 second */
98 #define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
99 #define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
100 #define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
101 #define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
102 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
103 					   - '3' from resolv.h */
104 
105 #define NONE cpu_to_be32(INADDR_NONE)
106 #define ANY cpu_to_be32(INADDR_ANY)
107 
108 /*
109  * Public IP configuration
110  */
111 
112 /* This is used by platforms which might be able to set the ipconfig
113  * variables using firmware environment vars.  If this is set, it will
114  * ignore such firmware variables.
115  */
116 int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
117 
118 static int ic_enable __initdata = 0;		/* IP config enabled? */
119 
120 /* Protocol choice */
121 int ic_proto_enabled __initdata = 0
122 #ifdef IPCONFIG_BOOTP
123 			| IC_BOOTP
124 #endif
125 #ifdef CONFIG_IP_PNP_DHCP
126 			| IC_USE_DHCP
127 #endif
128 #ifdef IPCONFIG_RARP
129 			| IC_RARP
130 #endif
131 			;
132 
133 static int ic_host_name_set __initdata = 0;	/* Host name set by us? */
134 
135 __be32 ic_myaddr = NONE;		/* My IP address */
136 static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
137 __be32 ic_gateway = NONE;	/* Gateway IP address */
138 
139 __be32 ic_addrservaddr = NONE;	/* IP Address of the IP addresses'server */
140 
141 __be32 ic_servaddr = NONE;	/* Boot server IP address */
142 
143 __be32 root_server_addr = NONE;	/* Address of NFS server */
144 u8 root_server_path[256] = { 0, };	/* Path to mount as root */
145 
146 __be32 ic_dev_xid;		/* Device under configuration */
147 
148 /* vendor class identifier */
149 static char vendor_class_identifier[253] __initdata;
150 
151 /* Persistent data: */
152 
153 static int ic_proto_used;			/* Protocol used, if any */
154 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
155 static u8 ic_domain[64];		/* DNS (not NIS) domain name */
156 
157 /*
158  * Private state.
159  */
160 
161 /* Name of user-selected boot device */
162 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
163 
164 /* Protocols supported by available interfaces */
165 static int ic_proto_have_if __initdata = 0;
166 
167 /* MTU for boot device */
168 static int ic_dev_mtu __initdata = 0;
169 
170 #ifdef IPCONFIG_DYNAMIC
171 static DEFINE_SPINLOCK(ic_recv_lock);
172 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
173 #endif
174 #ifdef IPCONFIG_DHCP
175 static int ic_dhcp_msgtype __initdata = 0;	/* DHCP msg type received */
176 #endif
177 
178 
179 /*
180  *	Network devices
181  */
182 
183 struct ic_device {
184 	struct ic_device *next;
185 	struct net_device *dev;
186 	unsigned short flags;
187 	short able;
188 	__be32 xid;
189 };
190 
191 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
192 static struct net_device *ic_dev __initdata = NULL;	/* Selected device */
193 
194 static bool __init ic_is_init_dev(struct net_device *dev)
195 {
196 	if (dev->flags & IFF_LOOPBACK)
197 		return false;
198 	return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
199 	    (!(dev->flags & IFF_LOOPBACK) &&
200 	     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
201 	     strncmp(dev->name, "dummy", 5));
202 }
203 
204 static int __init ic_open_devs(void)
205 {
206 	struct ic_device *d, **last;
207 	struct net_device *dev;
208 	unsigned short oflags;
209 	unsigned long start, next_msg;
210 
211 	last = &ic_first_dev;
212 	rtnl_lock();
213 
214 	/* bring loopback device up first */
215 	for_each_netdev(&init_net, dev) {
216 		if (!(dev->flags & IFF_LOOPBACK))
217 			continue;
218 		if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
219 			pr_err("IP-Config: Failed to open %s\n", dev->name);
220 	}
221 
222 	for_each_netdev(&init_net, dev) {
223 		if (ic_is_init_dev(dev)) {
224 			int able = 0;
225 			if (dev->mtu >= 364)
226 				able |= IC_BOOTP;
227 			else
228 				pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small",
229 					dev->name, dev->mtu);
230 			if (!(dev->flags & IFF_NOARP))
231 				able |= IC_RARP;
232 			able &= ic_proto_enabled;
233 			if (ic_proto_enabled && !able)
234 				continue;
235 			oflags = dev->flags;
236 			if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
237 				pr_err("IP-Config: Failed to open %s\n",
238 				       dev->name);
239 				continue;
240 			}
241 			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
242 				rtnl_unlock();
243 				return -ENOMEM;
244 			}
245 			d->dev = dev;
246 			*last = d;
247 			last = &d->next;
248 			d->flags = oflags;
249 			d->able = able;
250 			if (able & IC_BOOTP)
251 				get_random_bytes(&d->xid, sizeof(__be32));
252 			else
253 				d->xid = 0;
254 			ic_proto_have_if |= able;
255 			DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
256 				dev->name, able, d->xid));
257 		}
258 	}
259 
260 	/* no point in waiting if we could not bring up at least one device */
261 	if (!ic_first_dev)
262 		goto have_carrier;
263 
264 	/* wait for a carrier on at least one device */
265 	start = jiffies;
266 	next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
267 	while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
268 		int wait, elapsed;
269 
270 		for_each_netdev(&init_net, dev)
271 			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
272 				goto have_carrier;
273 
274 		msleep(1);
275 
276 		if time_before(jiffies, next_msg)
277 			continue;
278 
279 		elapsed = jiffies_to_msecs(jiffies - start);
280 		wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
281 		pr_info("Waiting up to %d more seconds for network.\n", wait);
282 		next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
283 	}
284 have_carrier:
285 	rtnl_unlock();
286 
287 	*last = NULL;
288 
289 	if (!ic_first_dev) {
290 		if (user_dev_name[0])
291 			pr_err("IP-Config: Device `%s' not found\n",
292 			       user_dev_name);
293 		else
294 			pr_err("IP-Config: No network devices available\n");
295 		return -ENODEV;
296 	}
297 	return 0;
298 }
299 
300 static void __init ic_close_devs(void)
301 {
302 	struct ic_device *d, *next;
303 	struct net_device *dev;
304 
305 	rtnl_lock();
306 	next = ic_first_dev;
307 	while ((d = next)) {
308 		next = d->next;
309 		dev = d->dev;
310 		if (dev != ic_dev) {
311 			DBG(("IP-Config: Downing %s\n", dev->name));
312 			dev_change_flags(dev, d->flags);
313 		}
314 		kfree(d);
315 	}
316 	rtnl_unlock();
317 }
318 
319 /*
320  *	Interface to various network functions.
321  */
322 
323 static inline void
324 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
325 {
326 	sin->sin_family = AF_INET;
327 	sin->sin_addr.s_addr = addr;
328 	sin->sin_port = port;
329 }
330 
331 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
332 {
333 	int res;
334 
335 	mm_segment_t oldfs = get_fs();
336 	set_fs(get_ds());
337 	res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
338 	set_fs(oldfs);
339 	return res;
340 }
341 
342 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
343 {
344 	int res;
345 
346 	mm_segment_t oldfs = get_fs();
347 	set_fs(get_ds());
348 	res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
349 	set_fs(oldfs);
350 	return res;
351 }
352 
353 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
354 {
355 	int res;
356 
357 	mm_segment_t oldfs = get_fs();
358 	set_fs(get_ds());
359 	res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
360 	set_fs(oldfs);
361 	return res;
362 }
363 
364 /*
365  *	Set up interface addresses and routes.
366  */
367 
368 static int __init ic_setup_if(void)
369 {
370 	struct ifreq ir;
371 	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
372 	int err;
373 
374 	memset(&ir, 0, sizeof(ir));
375 	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
376 	set_sockaddr(sin, ic_myaddr, 0);
377 	if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
378 		pr_err("IP-Config: Unable to set interface address (%d)\n",
379 		       err);
380 		return -1;
381 	}
382 	set_sockaddr(sin, ic_netmask, 0);
383 	if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
384 		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
385 		       err);
386 		return -1;
387 	}
388 	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
389 	if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
390 		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
391 		       err);
392 		return -1;
393 	}
394 	/* Handle the case where we need non-standard MTU on the boot link (a network
395 	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
396 	 * out, we'll try to muddle along.
397 	 */
398 	if (ic_dev_mtu != 0) {
399 		strcpy(ir.ifr_name, ic_dev->name);
400 		ir.ifr_mtu = ic_dev_mtu;
401 		if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
402 			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
403 			       ic_dev_mtu, err);
404 	}
405 	return 0;
406 }
407 
408 static int __init ic_setup_routes(void)
409 {
410 	/* No need to setup device routes, only the default route... */
411 
412 	if (ic_gateway != NONE) {
413 		struct rtentry rm;
414 		int err;
415 
416 		memset(&rm, 0, sizeof(rm));
417 		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
418 			pr_err("IP-Config: Gateway not on directly connected network\n");
419 			return -1;
420 		}
421 		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
422 		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
423 		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
424 		rm.rt_flags = RTF_UP | RTF_GATEWAY;
425 		if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
426 			pr_err("IP-Config: Cannot add default route (%d)\n",
427 			       err);
428 			return -1;
429 		}
430 	}
431 
432 	return 0;
433 }
434 
435 /*
436  *	Fill in default values for all missing parameters.
437  */
438 
439 static int __init ic_defaults(void)
440 {
441 	/*
442 	 *	At this point we have no userspace running so need not
443 	 *	claim locks on system_utsname
444 	 */
445 
446 	if (!ic_host_name_set)
447 		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
448 
449 	if (root_server_addr == NONE)
450 		root_server_addr = ic_servaddr;
451 
452 	if (ic_netmask == NONE) {
453 		if (IN_CLASSA(ntohl(ic_myaddr)))
454 			ic_netmask = htonl(IN_CLASSA_NET);
455 		else if (IN_CLASSB(ntohl(ic_myaddr)))
456 			ic_netmask = htonl(IN_CLASSB_NET);
457 		else if (IN_CLASSC(ntohl(ic_myaddr)))
458 			ic_netmask = htonl(IN_CLASSC_NET);
459 		else {
460 			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
461 			       &ic_myaddr);
462 			return -1;
463 		}
464 		printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
465 	}
466 
467 	return 0;
468 }
469 
470 /*
471  *	RARP support.
472  */
473 
474 #ifdef IPCONFIG_RARP
475 
476 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
477 
478 static struct packet_type rarp_packet_type __initdata = {
479 	.type =	cpu_to_be16(ETH_P_RARP),
480 	.func =	ic_rarp_recv,
481 };
482 
483 static inline void __init ic_rarp_init(void)
484 {
485 	dev_add_pack(&rarp_packet_type);
486 }
487 
488 static inline void __init ic_rarp_cleanup(void)
489 {
490 	dev_remove_pack(&rarp_packet_type);
491 }
492 
493 /*
494  *  Process received RARP packet.
495  */
496 static int __init
497 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
498 {
499 	struct arphdr *rarp;
500 	unsigned char *rarp_ptr;
501 	__be32 sip, tip;
502 	unsigned char *sha, *tha;		/* s for "source", t for "target" */
503 	struct ic_device *d;
504 
505 	if (!net_eq(dev_net(dev), &init_net))
506 		goto drop;
507 
508 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
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 	sha = rarp_ptr;
554 	rarp_ptr += dev->addr_len;
555 	memcpy(&sip, rarp_ptr, 4);
556 	rarp_ptr += 4;
557 	tha = rarp_ptr;
558 	rarp_ptr += dev->addr_len;
559 	memcpy(&tip, rarp_ptr, 4);
560 
561 	/* Discard packets which are not meant for us. */
562 	if (memcmp(tha, dev->dev_addr, dev->addr_len))
563 		goto drop_unlock;
564 
565 	/* Discard packets which are not from specified server. */
566 	if (ic_servaddr != NONE && ic_servaddr != sip)
567 		goto drop_unlock;
568 
569 	/* We have a winner! */
570 	ic_dev = dev;
571 	if (ic_myaddr == NONE)
572 		ic_myaddr = tip;
573 	ic_servaddr = sip;
574 	ic_addrservaddr = sip;
575 	ic_got_reply = IC_RARP;
576 
577 drop_unlock:
578 	/* Show's over.  Nothing to see here.  */
579 	spin_unlock(&ic_recv_lock);
580 
581 drop:
582 	/* Throw the packet out. */
583 	kfree_skb(skb);
584 	return 0;
585 }
586 
587 
588 /*
589  *  Send RARP request packet over a single interface.
590  */
591 static void __init ic_rarp_send_if(struct ic_device *d)
592 {
593 	struct net_device *dev = d->dev;
594 	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
595 		 dev->dev_addr, dev->dev_addr);
596 }
597 #endif
598 
599 /*
600  *  Predefine Nameservers
601  */
602 static inline void __init ic_nameservers_predef(void)
603 {
604 	int i;
605 
606 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
607 		ic_nameservers[i] = NONE;
608 }
609 
610 /*
611  *	DHCP/BOOTP support.
612  */
613 
614 #ifdef IPCONFIG_BOOTP
615 
616 struct bootp_pkt {		/* BOOTP packet format */
617 	struct iphdr iph;	/* IP header */
618 	struct udphdr udph;	/* UDP header */
619 	u8 op;			/* 1=request, 2=reply */
620 	u8 htype;		/* HW address type */
621 	u8 hlen;		/* HW address length */
622 	u8 hops;		/* Used only by gateways */
623 	__be32 xid;		/* Transaction ID */
624 	__be16 secs;		/* Seconds since we started */
625 	__be16 flags;		/* Just what it says */
626 	__be32 client_ip;		/* Client's IP address if known */
627 	__be32 your_ip;		/* Assigned IP address */
628 	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
629 	__be32 relay_ip;		/* IP address of BOOTP relay */
630 	u8 hw_addr[16];		/* Client's HW address */
631 	u8 serv_name[64];	/* Server host name */
632 	u8 boot_file[128];	/* Name of boot file */
633 	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
634 };
635 
636 /* packet ops */
637 #define BOOTP_REQUEST	1
638 #define BOOTP_REPLY	2
639 
640 /* DHCP message types */
641 #define DHCPDISCOVER	1
642 #define DHCPOFFER	2
643 #define DHCPREQUEST	3
644 #define DHCPDECLINE	4
645 #define DHCPACK		5
646 #define DHCPNAK		6
647 #define DHCPRELEASE	7
648 #define DHCPINFORM	8
649 
650 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
651 
652 static struct packet_type bootp_packet_type __initdata = {
653 	.type =	cpu_to_be16(ETH_P_IP),
654 	.func =	ic_bootp_recv,
655 };
656 
657 
658 /*
659  *  Initialize DHCP/BOOTP extension fields in the request.
660  */
661 
662 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
663 
664 #ifdef IPCONFIG_DHCP
665 
666 static void __init
667 ic_dhcp_init_options(u8 *options)
668 {
669 	u8 mt = ((ic_servaddr == NONE)
670 		 ? DHCPDISCOVER : DHCPREQUEST);
671 	u8 *e = options;
672 	int len;
673 
674 #ifdef IPCONFIG_DEBUG
675 	printk("DHCP: Sending message type %d\n", mt);
676 #endif
677 
678 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
679 	e += 4;
680 
681 	*e++ = 53;		/* DHCP message type */
682 	*e++ = 1;
683 	*e++ = mt;
684 
685 	if (mt == DHCPREQUEST) {
686 		*e++ = 54;	/* Server ID (IP address) */
687 		*e++ = 4;
688 		memcpy(e, &ic_servaddr, 4);
689 		e += 4;
690 
691 		*e++ = 50;	/* Requested IP address */
692 		*e++ = 4;
693 		memcpy(e, &ic_myaddr, 4);
694 		e += 4;
695 	}
696 
697 	/* always? */
698 	{
699 		static const u8 ic_req_params[] = {
700 			1,	/* Subnet mask */
701 			3,	/* Default gateway */
702 			6,	/* DNS server */
703 			12,	/* Host name */
704 			15,	/* Domain name */
705 			17,	/* Boot path */
706 			26,	/* MTU */
707 			40,	/* NIS domain name */
708 		};
709 
710 		*e++ = 55;	/* Parameter request list */
711 		*e++ = sizeof(ic_req_params);
712 		memcpy(e, ic_req_params, sizeof(ic_req_params));
713 		e += sizeof(ic_req_params);
714 
715 		if (ic_host_name_set) {
716 			*e++ = 12;	/* host-name */
717 			len = strlen(utsname()->nodename);
718 			*e++ = len;
719 			memcpy(e, utsname()->nodename, len);
720 			e += len;
721 		}
722 		if (*vendor_class_identifier) {
723 			pr_info("DHCP: sending class identifier \"%s\"\n",
724 				vendor_class_identifier);
725 			*e++ = 60;	/* Class-identifier */
726 			len = strlen(vendor_class_identifier);
727 			*e++ = len;
728 			memcpy(e, vendor_class_identifier, len);
729 			e += len;
730 		}
731 	}
732 
733 	*e++ = 255;	/* End of the list */
734 }
735 
736 #endif /* IPCONFIG_DHCP */
737 
738 static void __init ic_bootp_init_ext(u8 *e)
739 {
740 	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
741 	e += 4;
742 	*e++ = 1;		/* Subnet mask request */
743 	*e++ = 4;
744 	e += 4;
745 	*e++ = 3;		/* Default gateway request */
746 	*e++ = 4;
747 	e += 4;
748 	*e++ = 5;		/* Name server request */
749 	*e++ = 8;
750 	e += 8;
751 	*e++ = 12;		/* Host name request */
752 	*e++ = 32;
753 	e += 32;
754 	*e++ = 40;		/* NIS Domain name request */
755 	*e++ = 32;
756 	e += 32;
757 	*e++ = 17;		/* Boot path */
758 	*e++ = 40;
759 	e += 40;
760 
761 	*e++ = 57;		/* set extension buffer size for reply */
762 	*e++ = 2;
763 	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
764 	*e++ = 150;
765 
766 	*e++ = 255;		/* End of the list */
767 }
768 
769 
770 /*
771  *  Initialize the DHCP/BOOTP mechanism.
772  */
773 static inline void __init ic_bootp_init(void)
774 {
775 	ic_nameservers_predef();
776 
777 	dev_add_pack(&bootp_packet_type);
778 }
779 
780 
781 /*
782  *  DHCP/BOOTP cleanup.
783  */
784 static inline void __init ic_bootp_cleanup(void)
785 {
786 	dev_remove_pack(&bootp_packet_type);
787 }
788 
789 
790 /*
791  *  Send DHCP/BOOTP request to single interface.
792  */
793 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
794 {
795 	struct net_device *dev = d->dev;
796 	struct sk_buff *skb;
797 	struct bootp_pkt *b;
798 	struct iphdr *h;
799 	int hlen = LL_RESERVED_SPACE(dev);
800 	int tlen = dev->needed_tailroom;
801 
802 	/* Allocate packet */
803 	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
804 			GFP_KERNEL);
805 	if (!skb)
806 		return;
807 	skb_reserve(skb, hlen);
808 	b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
809 	memset(b, 0, sizeof(struct bootp_pkt));
810 
811 	/* Construct IP header */
812 	skb_reset_network_header(skb);
813 	h = ip_hdr(skb);
814 	h->version = 4;
815 	h->ihl = 5;
816 	h->tot_len = htons(sizeof(struct bootp_pkt));
817 	h->frag_off = htons(IP_DF);
818 	h->ttl = 64;
819 	h->protocol = IPPROTO_UDP;
820 	h->daddr = htonl(INADDR_BROADCAST);
821 	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
822 
823 	/* Construct UDP header */
824 	b->udph.source = htons(68);
825 	b->udph.dest = htons(67);
826 	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
827 	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
828 
829 	/* Construct DHCP/BOOTP header */
830 	b->op = BOOTP_REQUEST;
831 	if (dev->type < 256) /* check for false types */
832 		b->htype = dev->type;
833 	else if (dev->type == ARPHRD_FDDI)
834 		b->htype = ARPHRD_ETHER;
835 	else {
836 		printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
837 		b->htype = dev->type; /* can cause undefined behavior */
838 	}
839 
840 	/* server_ip and your_ip address are both already zero per RFC2131 */
841 	b->hlen = dev->addr_len;
842 	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
843 	b->secs = htons(jiffies_diff / HZ);
844 	b->xid = d->xid;
845 
846 	/* add DHCP options or BOOTP extensions */
847 #ifdef IPCONFIG_DHCP
848 	if (ic_proto_enabled & IC_USE_DHCP)
849 		ic_dhcp_init_options(b->exten);
850 	else
851 #endif
852 		ic_bootp_init_ext(b->exten);
853 
854 	/* Chain packet down the line... */
855 	skb->dev = dev;
856 	skb->protocol = htons(ETH_P_IP);
857 	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
858 			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
859 		kfree_skb(skb);
860 		printk("E");
861 		return;
862 	}
863 
864 	if (dev_queue_xmit(skb) < 0)
865 		printk("E");
866 }
867 
868 
869 /*
870  *  Copy BOOTP-supplied string if not already set.
871  */
872 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
873 {
874 	if (!len)
875 		return 0;
876 	if (len > max-1)
877 		len = max-1;
878 	memcpy(dest, src, len);
879 	dest[len] = '\0';
880 	return 1;
881 }
882 
883 
884 /*
885  *  Process BOOTP extensions.
886  */
887 static void __init ic_do_bootp_ext(u8 *ext)
888 {
889 	u8 servers;
890 	int i;
891 	__be16 mtu;
892 
893 #ifdef IPCONFIG_DEBUG
894 	u8 *c;
895 
896 	printk("DHCP/BOOTP: Got extension %d:",*ext);
897 	for (c=ext+2; c<ext+2+ext[1]; c++)
898 		printk(" %02x", *c);
899 	printk("\n");
900 #endif
901 
902 	switch (*ext++) {
903 	case 1:		/* Subnet mask */
904 		if (ic_netmask == NONE)
905 			memcpy(&ic_netmask, ext+1, 4);
906 		break;
907 	case 3:		/* Default gateway */
908 		if (ic_gateway == NONE)
909 			memcpy(&ic_gateway, ext+1, 4);
910 		break;
911 	case 6:		/* DNS server */
912 		servers= *ext/4;
913 		if (servers > CONF_NAMESERVERS_MAX)
914 			servers = CONF_NAMESERVERS_MAX;
915 		for (i = 0; i < servers; i++) {
916 			if (ic_nameservers[i] == NONE)
917 				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
918 		}
919 		break;
920 	case 12:	/* Host name */
921 		ic_bootp_string(utsname()->nodename, ext+1, *ext,
922 				__NEW_UTS_LEN);
923 		ic_host_name_set = 1;
924 		break;
925 	case 15:	/* Domain name (DNS) */
926 		ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
927 		break;
928 	case 17:	/* Root path */
929 		if (!root_server_path[0])
930 			ic_bootp_string(root_server_path, ext+1, *ext,
931 					sizeof(root_server_path));
932 		break;
933 	case 26:	/* Interface MTU */
934 		memcpy(&mtu, ext+1, sizeof(mtu));
935 		ic_dev_mtu = ntohs(mtu);
936 		break;
937 	case 40:	/* NIS Domain name (_not_ DNS) */
938 		ic_bootp_string(utsname()->domainname, ext+1, *ext,
939 				__NEW_UTS_LEN);
940 		break;
941 	}
942 }
943 
944 
945 /*
946  *  Receive BOOTP reply.
947  */
948 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
949 {
950 	struct bootp_pkt *b;
951 	struct iphdr *h;
952 	struct ic_device *d;
953 	int len, ext_len;
954 
955 	if (!net_eq(dev_net(dev), &init_net))
956 		goto drop;
957 
958 	/* Perform verifications before taking the lock.  */
959 	if (skb->pkt_type == PACKET_OTHERHOST)
960 		goto drop;
961 
962 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
963 		return NET_RX_DROP;
964 
965 	if (!pskb_may_pull(skb,
966 			   sizeof(struct iphdr) +
967 			   sizeof(struct udphdr)))
968 		goto drop;
969 
970 	b = (struct bootp_pkt *)skb_network_header(skb);
971 	h = &b->iph;
972 
973 	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
974 		goto drop;
975 
976 	/* Fragments are not supported */
977 	if (ip_is_fragment(h)) {
978 		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
979 		goto drop;
980 	}
981 
982 	if (skb->len < ntohs(h->tot_len))
983 		goto drop;
984 
985 	if (ip_fast_csum((char *) h, h->ihl))
986 		goto drop;
987 
988 	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
989 		goto drop;
990 
991 	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
992 		goto drop;
993 
994 	len = ntohs(b->udph.len) - sizeof(struct udphdr);
995 	ext_len = len - (sizeof(*b) -
996 			 sizeof(struct iphdr) -
997 			 sizeof(struct udphdr) -
998 			 sizeof(b->exten));
999 	if (ext_len < 0)
1000 		goto drop;
1001 
1002 	/* Ok the front looks good, make sure we can get at the rest.  */
1003 	if (!pskb_may_pull(skb, skb->len))
1004 		goto drop;
1005 
1006 	b = (struct bootp_pkt *)skb_network_header(skb);
1007 	h = &b->iph;
1008 
1009 	/* One reply at a time, please. */
1010 	spin_lock(&ic_recv_lock);
1011 
1012 	/* If we already have a reply, just drop the packet */
1013 	if (ic_got_reply)
1014 		goto drop_unlock;
1015 
1016 	/* Find the ic_device that the packet arrived on */
1017 	d = ic_first_dev;
1018 	while (d && d->dev != dev)
1019 		d = d->next;
1020 	if (!d)
1021 		goto drop_unlock;  /* should never happen */
1022 
1023 	/* Is it a reply to our BOOTP request? */
1024 	if (b->op != BOOTP_REPLY ||
1025 	    b->xid != d->xid) {
1026 		net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1027 				    b->op, b->xid);
1028 		goto drop_unlock;
1029 	}
1030 
1031 	/* Is it a reply for the device we are configuring? */
1032 	if (b->xid != ic_dev_xid) {
1033 		net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1034 		goto drop_unlock;
1035 	}
1036 
1037 	/* Parse extensions */
1038 	if (ext_len >= 4 &&
1039 	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1040 		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1041 		u8 *ext;
1042 
1043 #ifdef IPCONFIG_DHCP
1044 		if (ic_proto_enabled & IC_USE_DHCP) {
1045 			__be32 server_id = NONE;
1046 			int mt = 0;
1047 
1048 			ext = &b->exten[4];
1049 			while (ext < end && *ext != 0xff) {
1050 				u8 *opt = ext++;
1051 				if (*opt == 0)	/* Padding */
1052 					continue;
1053 				ext += *ext + 1;
1054 				if (ext >= end)
1055 					break;
1056 				switch (*opt) {
1057 				case 53:	/* Message type */
1058 					if (opt[1])
1059 						mt = opt[2];
1060 					break;
1061 				case 54:	/* Server ID (IP address) */
1062 					if (opt[1] >= 4)
1063 						memcpy(&server_id, opt + 2, 4);
1064 					break;
1065 				}
1066 			}
1067 
1068 #ifdef IPCONFIG_DEBUG
1069 			printk("DHCP: Got message type %d\n", mt);
1070 #endif
1071 
1072 			switch (mt) {
1073 			case DHCPOFFER:
1074 				/* While in the process of accepting one offer,
1075 				 * ignore all others.
1076 				 */
1077 				if (ic_myaddr != NONE)
1078 					goto drop_unlock;
1079 
1080 				/* Let's accept that offer. */
1081 				ic_myaddr = b->your_ip;
1082 				ic_servaddr = server_id;
1083 #ifdef IPCONFIG_DEBUG
1084 				printk("DHCP: Offered address %pI4 by server %pI4\n",
1085 				       &ic_myaddr, &b->iph.saddr);
1086 #endif
1087 				/* The DHCP indicated server address takes
1088 				 * precedence over the bootp header one if
1089 				 * they are different.
1090 				 */
1091 				if ((server_id != NONE) &&
1092 				    (b->server_ip != server_id))
1093 					b->server_ip = ic_servaddr;
1094 				break;
1095 
1096 			case DHCPACK:
1097 				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1098 					goto drop_unlock;
1099 
1100 				/* Yeah! */
1101 				break;
1102 
1103 			default:
1104 				/* Urque.  Forget it*/
1105 				ic_myaddr = NONE;
1106 				ic_servaddr = NONE;
1107 				goto drop_unlock;
1108 			}
1109 
1110 			ic_dhcp_msgtype = mt;
1111 
1112 		}
1113 #endif /* IPCONFIG_DHCP */
1114 
1115 		ext = &b->exten[4];
1116 		while (ext < end && *ext != 0xff) {
1117 			u8 *opt = ext++;
1118 			if (*opt == 0)	/* Padding */
1119 				continue;
1120 			ext += *ext + 1;
1121 			if (ext < end)
1122 				ic_do_bootp_ext(opt);
1123 		}
1124 	}
1125 
1126 	/* We have a winner! */
1127 	ic_dev = dev;
1128 	ic_myaddr = b->your_ip;
1129 	ic_servaddr = b->server_ip;
1130 	ic_addrservaddr = b->iph.saddr;
1131 	if (ic_gateway == NONE && b->relay_ip)
1132 		ic_gateway = b->relay_ip;
1133 	if (ic_nameservers[0] == NONE)
1134 		ic_nameservers[0] = ic_servaddr;
1135 	ic_got_reply = IC_BOOTP;
1136 
1137 drop_unlock:
1138 	/* Show's over.  Nothing to see here.  */
1139 	spin_unlock(&ic_recv_lock);
1140 
1141 drop:
1142 	/* Throw the packet out. */
1143 	kfree_skb(skb);
1144 
1145 	return 0;
1146 }
1147 
1148 
1149 #endif
1150 
1151 
1152 /*
1153  *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1154  */
1155 
1156 #ifdef IPCONFIG_DYNAMIC
1157 
1158 static int __init ic_dynamic(void)
1159 {
1160 	int retries;
1161 	struct ic_device *d;
1162 	unsigned long start_jiffies, timeout, jiff;
1163 	int do_bootp = ic_proto_have_if & IC_BOOTP;
1164 	int do_rarp = ic_proto_have_if & IC_RARP;
1165 
1166 	/*
1167 	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1168 	 * This routine gets only called when some pieces of information
1169 	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1170 	 */
1171 	if (!ic_proto_enabled) {
1172 		pr_err("IP-Config: Incomplete network configuration information\n");
1173 		return -1;
1174 	}
1175 
1176 #ifdef IPCONFIG_BOOTP
1177 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1178 		pr_err("DHCP/BOOTP: No suitable device found\n");
1179 #endif
1180 #ifdef IPCONFIG_RARP
1181 	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1182 		pr_err("RARP: No suitable device found\n");
1183 #endif
1184 
1185 	if (!ic_proto_have_if)
1186 		/* Error message already printed */
1187 		return -1;
1188 
1189 	/*
1190 	 * Setup protocols
1191 	 */
1192 #ifdef IPCONFIG_BOOTP
1193 	if (do_bootp)
1194 		ic_bootp_init();
1195 #endif
1196 #ifdef IPCONFIG_RARP
1197 	if (do_rarp)
1198 		ic_rarp_init();
1199 #endif
1200 
1201 	/*
1202 	 * Send requests and wait, until we get an answer. This loop
1203 	 * seems to be a terrible waste of CPU time, but actually there is
1204 	 * only one process running at all, so we don't need to use any
1205 	 * scheduler functions.
1206 	 * [Actually we could now, but the nothing else running note still
1207 	 *  applies.. - AC]
1208 	 */
1209 	pr_notice("Sending %s%s%s requests .",
1210 		  do_bootp
1211 		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1212 		  (do_bootp && do_rarp) ? " and " : "",
1213 		  do_rarp ? "RARP" : "");
1214 
1215 	start_jiffies = jiffies;
1216 	d = ic_first_dev;
1217 	retries = CONF_SEND_RETRIES;
1218 	get_random_bytes(&timeout, sizeof(timeout));
1219 	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1220 	for (;;) {
1221 		/* Track the device we are configuring */
1222 		ic_dev_xid = d->xid;
1223 
1224 #ifdef IPCONFIG_BOOTP
1225 		if (do_bootp && (d->able & IC_BOOTP))
1226 			ic_bootp_send_if(d, jiffies - start_jiffies);
1227 #endif
1228 #ifdef IPCONFIG_RARP
1229 		if (do_rarp && (d->able & IC_RARP))
1230 			ic_rarp_send_if(d);
1231 #endif
1232 
1233 		jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1234 		while (time_before(jiffies, jiff) && !ic_got_reply)
1235 			schedule_timeout_uninterruptible(1);
1236 #ifdef IPCONFIG_DHCP
1237 		/* DHCP isn't done until we get a DHCPACK. */
1238 		if ((ic_got_reply & IC_BOOTP) &&
1239 		    (ic_proto_enabled & IC_USE_DHCP) &&
1240 		    ic_dhcp_msgtype != DHCPACK) {
1241 			ic_got_reply = 0;
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 	printk("IP-Config: Got %s answer from %pI4, ",
1284 		((ic_got_reply & IC_RARP) ? "RARP"
1285 		 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1286 	       &ic_addrservaddr);
1287 	pr_cont("my address is %pI4\n", &ic_myaddr);
1288 
1289 	return 0;
1290 }
1291 
1292 #endif /* IPCONFIG_DYNAMIC */
1293 
1294 #ifdef CONFIG_PROC_FS
1295 
1296 static int pnp_seq_show(struct seq_file *seq, void *v)
1297 {
1298 	int i;
1299 
1300 	if (ic_proto_used & IC_PROTO)
1301 		seq_printf(seq, "#PROTO: %s\n",
1302 			   (ic_proto_used & IC_RARP) ? "RARP"
1303 			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1304 	else
1305 		seq_puts(seq, "#MANUAL\n");
1306 
1307 	if (ic_domain[0])
1308 		seq_printf(seq,
1309 			   "domain %s\n", ic_domain);
1310 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1311 		if (ic_nameservers[i] != NONE)
1312 			seq_printf(seq, "nameserver %pI4\n",
1313 				   &ic_nameservers[i]);
1314 	}
1315 	if (ic_servaddr != NONE)
1316 		seq_printf(seq, "bootserver %pI4\n",
1317 			   &ic_servaddr);
1318 	return 0;
1319 }
1320 
1321 static int pnp_seq_open(struct inode *indoe, struct file *file)
1322 {
1323 	return single_open(file, pnp_seq_show, NULL);
1324 }
1325 
1326 static const struct file_operations pnp_seq_fops = {
1327 	.owner		= THIS_MODULE,
1328 	.open		= pnp_seq_open,
1329 	.read		= seq_read,
1330 	.llseek		= seq_lseek,
1331 	.release	= single_release,
1332 };
1333 #endif /* CONFIG_PROC_FS */
1334 
1335 /*
1336  *  Extract IP address from the parameter string if needed. Note that we
1337  *  need to have root_server_addr set _before_ IPConfig gets called as it
1338  *  can override it.
1339  */
1340 __be32 __init root_nfs_parse_addr(char *name)
1341 {
1342 	__be32 addr;
1343 	int octets = 0;
1344 	char *cp, *cq;
1345 
1346 	cp = cq = name;
1347 	while (octets < 4) {
1348 		while (*cp >= '0' && *cp <= '9')
1349 			cp++;
1350 		if (cp == cq || cp - cq > 3)
1351 			break;
1352 		if (*cp == '.' || octets == 3)
1353 			octets++;
1354 		if (octets < 4)
1355 			cp++;
1356 		cq = cp;
1357 	}
1358 	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1359 		if (*cp == ':')
1360 			*cp++ = '\0';
1361 		addr = in_aton(name);
1362 		memmove(name, cp, strlen(cp) + 1);
1363 	} else
1364 		addr = NONE;
1365 
1366 	return addr;
1367 }
1368 
1369 #define DEVICE_WAIT_MAX		12 /* 12 seconds */
1370 
1371 static int __init wait_for_devices(void)
1372 {
1373 	int i;
1374 
1375 	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1376 		struct net_device *dev;
1377 		int found = 0;
1378 
1379 		rtnl_lock();
1380 		for_each_netdev(&init_net, dev) {
1381 			if (ic_is_init_dev(dev)) {
1382 				found = 1;
1383 				break;
1384 			}
1385 		}
1386 		rtnl_unlock();
1387 		if (found)
1388 			return 0;
1389 		ssleep(1);
1390 	}
1391 	return -ENODEV;
1392 }
1393 
1394 /*
1395  *	IP Autoconfig dispatcher.
1396  */
1397 
1398 static int __init ip_auto_config(void)
1399 {
1400 	__be32 addr;
1401 #ifdef IPCONFIG_DYNAMIC
1402 	int retries = CONF_OPEN_RETRIES;
1403 #endif
1404 	int err;
1405 	unsigned int i;
1406 
1407 #ifdef CONFIG_PROC_FS
1408 	proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1409 #endif /* CONFIG_PROC_FS */
1410 
1411 	if (!ic_enable)
1412 		return 0;
1413 
1414 	DBG(("IP-Config: Entered.\n"));
1415 #ifdef IPCONFIG_DYNAMIC
1416  try_try_again:
1417 #endif
1418 	/* Wait for devices to appear */
1419 	err = wait_for_devices();
1420 	if (err)
1421 		return err;
1422 
1423 	/* Setup all network devices */
1424 	err = ic_open_devs();
1425 	if (err)
1426 		return err;
1427 
1428 	/* Give drivers a chance to settle */
1429 	msleep(CONF_POST_OPEN);
1430 
1431 	/*
1432 	 * If the config information is insufficient (e.g., our IP address or
1433 	 * IP address of the boot server is missing or we have multiple network
1434 	 * interfaces and no default was set), use BOOTP or RARP to get the
1435 	 * missing values.
1436 	 */
1437 	if (ic_myaddr == NONE ||
1438 #ifdef CONFIG_ROOT_NFS
1439 	    (root_server_addr == NONE &&
1440 	     ic_servaddr == NONE &&
1441 	     ROOT_DEV == Root_NFS) ||
1442 #endif
1443 	    ic_first_dev->next) {
1444 #ifdef IPCONFIG_DYNAMIC
1445 		if (ic_dynamic() < 0) {
1446 			ic_close_devs();
1447 
1448 			/*
1449 			 * I don't know why, but sometimes the
1450 			 * eepro100 driver (at least) gets upset and
1451 			 * doesn't work the first time it's opened.
1452 			 * But then if you close it and reopen it, it
1453 			 * works just fine.  So we need to try that at
1454 			 * least once before giving up.
1455 			 *
1456 			 * Also, if the root will be NFS-mounted, we
1457 			 * have nowhere to go if DHCP fails.  So we
1458 			 * just have to keep trying forever.
1459 			 *
1460 			 * 				-- Chip
1461 			 */
1462 #ifdef CONFIG_ROOT_NFS
1463 			if (ROOT_DEV ==  Root_NFS) {
1464 				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1465 				goto try_try_again;
1466 			}
1467 #endif
1468 
1469 			if (--retries) {
1470 				pr_err("IP-Config: Reopening network devices...\n");
1471 				goto try_try_again;
1472 			}
1473 
1474 			/* Oh, well.  At least we tried. */
1475 			pr_err("IP-Config: Auto-configuration of network failed\n");
1476 			return -1;
1477 		}
1478 #else /* !DYNAMIC */
1479 		pr_err("IP-Config: Incomplete network configuration information\n");
1480 		ic_close_devs();
1481 		return -1;
1482 #endif /* IPCONFIG_DYNAMIC */
1483 	} else {
1484 		/* Device selected manually or only one device -> use it */
1485 		ic_dev = ic_first_dev->dev;
1486 	}
1487 
1488 	addr = root_nfs_parse_addr(root_server_path);
1489 	if (root_server_addr == NONE)
1490 		root_server_addr = addr;
1491 
1492 	/*
1493 	 * Use defaults wherever applicable.
1494 	 */
1495 	if (ic_defaults() < 0)
1496 		return -1;
1497 
1498 	/*
1499 	 * Close all network devices except the device we've
1500 	 * autoconfigured and set up routes.
1501 	 */
1502 	ic_close_devs();
1503 	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1504 		return -1;
1505 
1506 	/*
1507 	 * Record which protocol was actually used.
1508 	 */
1509 #ifdef IPCONFIG_DYNAMIC
1510 	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1511 #endif
1512 
1513 #ifndef IPCONFIG_SILENT
1514 	/*
1515 	 * Clue in the operator.
1516 	 */
1517 	pr_info("IP-Config: Complete:\n");
1518 
1519 	pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1520 		ic_dev->name, ic_dev->addr_len, ic_dev->dev_addr,
1521 		&ic_myaddr, &ic_netmask, &ic_gateway);
1522 	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1523 		utsname()->nodename, ic_domain, utsname()->domainname);
1524 	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1525 		&ic_servaddr, &root_server_addr, root_server_path);
1526 	if (ic_dev_mtu)
1527 		pr_cont(", mtu=%d", ic_dev_mtu);
1528 	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1529 		if (ic_nameservers[i] != NONE) {
1530 			pr_info("     nameserver%u=%pI4",
1531 				i, &ic_nameservers[i]);
1532 			break;
1533 		}
1534 	for (i++; i < CONF_NAMESERVERS_MAX; i++)
1535 		if (ic_nameservers[i] != NONE)
1536 			pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1537 	pr_cont("\n");
1538 #endif /* !SILENT */
1539 
1540 	return 0;
1541 }
1542 
1543 late_initcall(ip_auto_config);
1544 
1545 
1546 /*
1547  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1548  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1549  */
1550 static int __init ic_proto_name(char *name)
1551 {
1552 	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1553 		return 1;
1554 	}
1555 	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1556 		return 0;
1557 	}
1558 #ifdef CONFIG_IP_PNP_DHCP
1559 	else if (!strcmp(name, "dhcp")) {
1560 		ic_proto_enabled &= ~IC_RARP;
1561 		return 1;
1562 	}
1563 #endif
1564 #ifdef CONFIG_IP_PNP_BOOTP
1565 	else if (!strcmp(name, "bootp")) {
1566 		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1567 		return 1;
1568 	}
1569 #endif
1570 #ifdef CONFIG_IP_PNP_RARP
1571 	else if (!strcmp(name, "rarp")) {
1572 		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1573 		return 1;
1574 	}
1575 #endif
1576 #ifdef IPCONFIG_DYNAMIC
1577 	else if (!strcmp(name, "both")) {
1578 		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1579 		return 1;
1580 	}
1581 #endif
1582 	return 0;
1583 }
1584 
1585 static int __init ip_auto_config_setup(char *addrs)
1586 {
1587 	char *cp, *ip, *dp;
1588 	int num = 0;
1589 
1590 	ic_set_manually = 1;
1591 	ic_enable = 1;
1592 
1593 	/*
1594 	 * If any dhcp, bootp etc options are set, leave autoconfig on
1595 	 * and skip the below static IP processing.
1596 	 */
1597 	if (ic_proto_name(addrs))
1598 		return 1;
1599 
1600 	/* If no static IP is given, turn off autoconfig and bail.  */
1601 	if (*addrs == 0 ||
1602 	    strcmp(addrs, "off") == 0 ||
1603 	    strcmp(addrs, "none") == 0) {
1604 		ic_enable = 0;
1605 		return 1;
1606 	}
1607 
1608 	ic_nameservers_predef();
1609 
1610 	/* Parse string for static IP assignment.  */
1611 	ip = addrs;
1612 	while (ip && *ip) {
1613 		if ((cp = strchr(ip, ':')))
1614 			*cp++ = '\0';
1615 		if (strlen(ip) > 0) {
1616 			DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1617 			switch (num) {
1618 			case 0:
1619 				if ((ic_myaddr = in_aton(ip)) == ANY)
1620 					ic_myaddr = NONE;
1621 				break;
1622 			case 1:
1623 				if ((ic_servaddr = in_aton(ip)) == ANY)
1624 					ic_servaddr = NONE;
1625 				break;
1626 			case 2:
1627 				if ((ic_gateway = in_aton(ip)) == ANY)
1628 					ic_gateway = NONE;
1629 				break;
1630 			case 3:
1631 				if ((ic_netmask = in_aton(ip)) == ANY)
1632 					ic_netmask = NONE;
1633 				break;
1634 			case 4:
1635 				if ((dp = strchr(ip, '.'))) {
1636 					*dp++ = '\0';
1637 					strlcpy(utsname()->domainname, dp,
1638 						sizeof(utsname()->domainname));
1639 				}
1640 				strlcpy(utsname()->nodename, ip,
1641 					sizeof(utsname()->nodename));
1642 				ic_host_name_set = 1;
1643 				break;
1644 			case 5:
1645 				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1646 				break;
1647 			case 6:
1648 				if (ic_proto_name(ip) == 0 &&
1649 				    ic_myaddr == NONE) {
1650 					ic_enable = 0;
1651 				}
1652 				break;
1653 			case 7:
1654 				if (CONF_NAMESERVERS_MAX >= 1) {
1655 					ic_nameservers[0] = in_aton(ip);
1656 					if (ic_nameservers[0] == ANY)
1657 						ic_nameservers[0] = NONE;
1658 				}
1659 				break;
1660 			case 8:
1661 				if (CONF_NAMESERVERS_MAX >= 2) {
1662 					ic_nameservers[1] = in_aton(ip);
1663 					if (ic_nameservers[1] == ANY)
1664 						ic_nameservers[1] = NONE;
1665 				}
1666 				break;
1667 			}
1668 		}
1669 		ip = cp;
1670 		num++;
1671 	}
1672 
1673 	return 1;
1674 }
1675 __setup("ip=", ip_auto_config_setup);
1676 
1677 static int __init nfsaddrs_config_setup(char *addrs)
1678 {
1679 	return ip_auto_config_setup(addrs);
1680 }
1681 __setup("nfsaddrs=", nfsaddrs_config_setup);
1682 
1683 static int __init vendor_class_identifier_setup(char *addrs)
1684 {
1685 	if (strlcpy(vendor_class_identifier, addrs,
1686 		    sizeof(vendor_class_identifier))
1687 	    >= sizeof(vendor_class_identifier))
1688 		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1689 			vendor_class_identifier);
1690 	return 1;
1691 }
1692 __setup("dhcpclass=", vendor_class_identifier_setup);
1693