xref: /kernel/linux/linux-5.10/net/ipv4/ipconfig.c (revision 8c2ecf20)
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
89/* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
90#define CONF_OPEN_RETRIES 	2	/* (Re)open devices twice */
91#define CONF_SEND_RETRIES 	6	/* Send six requests per open */
92#define CONF_BASE_TIMEOUT	(HZ*2)	/* Initial timeout: 2 seconds */
93#define CONF_TIMEOUT_RANDOM	(HZ)	/* Maximum amount of randomization */
94#define CONF_TIMEOUT_MULT	*7/4	/* Rate of timeout growth */
95#define CONF_TIMEOUT_MAX	(HZ*30)	/* Maximum allowed timeout */
96#define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
97					   - '3' from resolv.h */
98#define CONF_NTP_SERVERS_MAX   3	/* Maximum number of NTP servers */
99
100#define NONE cpu_to_be32(INADDR_NONE)
101#define ANY cpu_to_be32(INADDR_ANY)
102
103/* Wait for carrier timeout default in seconds */
104static unsigned int carrier_timeout = 120;
105
106/*
107 * Public IP configuration
108 */
109
110/* This is used by platforms which might be able to set the ipconfig
111 * variables using firmware environment vars.  If this is set, it will
112 * ignore such firmware variables.
113 */
114int ic_set_manually __initdata = 0;		/* IPconfig parameters set manually */
115
116static int ic_enable __initdata;		/* IP config enabled? */
117
118/* Protocol choice */
119int ic_proto_enabled __initdata = 0
120#ifdef IPCONFIG_BOOTP
121			| IC_BOOTP
122#endif
123#ifdef CONFIG_IP_PNP_DHCP
124			| IC_USE_DHCP
125#endif
126#ifdef IPCONFIG_RARP
127			| IC_RARP
128#endif
129			;
130
131static int ic_host_name_set __initdata;	/* Host name set by us? */
132
133__be32 ic_myaddr = NONE;		/* My IP address */
134static __be32 ic_netmask = NONE;	/* Netmask for local subnet */
135__be32 ic_gateway = NONE;	/* Gateway IP address */
136
137#ifdef IPCONFIG_DYNAMIC
138static __be32 ic_addrservaddr = NONE;	/* IP Address of the IP addresses'server */
139#endif
140
141__be32 ic_servaddr = NONE;	/* Boot server IP address */
142
143__be32 root_server_addr = NONE;	/* Address of NFS server */
144u8 root_server_path[256] = { 0, };	/* Path to mount as root */
145
146/* vendor class identifier */
147static char vendor_class_identifier[253] __initdata;
148
149#if defined(CONFIG_IP_PNP_DHCP)
150static char dhcp_client_identifier[253] __initdata;
151#endif
152
153/* Persistent data: */
154
155#ifdef IPCONFIG_DYNAMIC
156static int ic_proto_used;			/* Protocol used, if any */
157#else
158#define ic_proto_used 0
159#endif
160static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
161static __be32 ic_ntp_servers[CONF_NTP_SERVERS_MAX]; /* NTP server IP addresses */
162static u8 ic_domain[64];		/* DNS (not NIS) domain name */
163
164/*
165 * Private state.
166 */
167
168/* Name of user-selected boot device */
169static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
170
171/* Protocols supported by available interfaces */
172static int ic_proto_have_if __initdata;
173
174/* MTU for boot device */
175static int ic_dev_mtu __initdata;
176
177#ifdef IPCONFIG_DYNAMIC
178static DEFINE_SPINLOCK(ic_recv_lock);
179static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
180#endif
181#ifdef IPCONFIG_DHCP
182static int ic_dhcp_msgtype __initdata;	/* DHCP msg type received */
183#endif
184
185
186/*
187 *	Network devices
188 */
189
190struct ic_device {
191	struct ic_device *next;
192	struct net_device *dev;
193	unsigned short flags;
194	short able;
195	__be32 xid;
196};
197
198static struct ic_device *ic_first_dev __initdata;	/* List of open device */
199static struct ic_device *ic_dev __initdata;		/* Selected device */
200
201static bool __init ic_is_init_dev(struct net_device *dev)
202{
203	if (dev->flags & IFF_LOOPBACK)
204		return false;
205	return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
206	    (!(dev->flags & IFF_LOOPBACK) &&
207	     (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
208	     strncmp(dev->name, "dummy", 5));
209}
210
211static int __init ic_open_devs(void)
212{
213	struct ic_device *d, **last;
214	struct net_device *dev;
215	unsigned short oflags;
216	unsigned long start, next_msg;
217
218	last = &ic_first_dev;
219	rtnl_lock();
220
221	/* bring loopback and DSA master network devices up first */
222	for_each_netdev(&init_net, dev) {
223		if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
224			continue;
225		if (dev_change_flags(dev, dev->flags | IFF_UP, NULL) < 0)
226			pr_err("IP-Config: Failed to open %s\n", dev->name);
227	}
228
229	for_each_netdev(&init_net, dev) {
230		if (ic_is_init_dev(dev)) {
231			int able = 0;
232			if (dev->mtu >= 364)
233				able |= IC_BOOTP;
234			else
235				pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
236					dev->name, dev->mtu);
237			if (!(dev->flags & IFF_NOARP))
238				able |= IC_RARP;
239			able &= ic_proto_enabled;
240			if (ic_proto_enabled && !able)
241				continue;
242			oflags = dev->flags;
243			if (dev_change_flags(dev, oflags | IFF_UP, NULL) < 0) {
244				pr_err("IP-Config: Failed to open %s\n",
245				       dev->name);
246				continue;
247			}
248			if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
249				rtnl_unlock();
250				return -ENOMEM;
251			}
252			d->dev = dev;
253			*last = d;
254			last = &d->next;
255			d->flags = oflags;
256			d->able = able;
257			if (able & IC_BOOTP)
258				get_random_bytes(&d->xid, sizeof(__be32));
259			else
260				d->xid = 0;
261			ic_proto_have_if |= able;
262			pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
263				 dev->name, able, d->xid);
264		}
265	}
266
267	/* no point in waiting if we could not bring up at least one device */
268	if (!ic_first_dev)
269		goto have_carrier;
270
271	/* wait for a carrier on at least one device */
272	start = jiffies;
273	next_msg = start + msecs_to_jiffies(20000);
274	while (time_before(jiffies, start +
275			   msecs_to_jiffies(carrier_timeout * 1000))) {
276		int wait, elapsed;
277
278		for_each_netdev(&init_net, dev)
279			if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
280				goto have_carrier;
281
282		msleep(1);
283
284		if (time_before(jiffies, next_msg))
285			continue;
286
287		elapsed = jiffies_to_msecs(jiffies - start);
288		wait = (carrier_timeout * 1000 - elapsed + 500) / 1000;
289		pr_info("Waiting up to %d more seconds for network.\n", wait);
290		next_msg = jiffies + msecs_to_jiffies(20000);
291	}
292have_carrier:
293	rtnl_unlock();
294
295	*last = NULL;
296
297	if (!ic_first_dev) {
298		if (user_dev_name[0])
299			pr_err("IP-Config: Device `%s' not found\n",
300			       user_dev_name);
301		else
302			pr_err("IP-Config: No network devices available\n");
303		return -ENODEV;
304	}
305	return 0;
306}
307
308static void __init ic_close_devs(void)
309{
310	struct ic_device *d, *next;
311	struct net_device *dev;
312
313	rtnl_lock();
314	next = ic_first_dev;
315	while ((d = next)) {
316		next = d->next;
317		dev = d->dev;
318		if (d != ic_dev && !netdev_uses_dsa(dev)) {
319			pr_debug("IP-Config: Downing %s\n", dev->name);
320			dev_change_flags(dev, d->flags, NULL);
321		}
322		kfree(d);
323	}
324	rtnl_unlock();
325}
326
327/*
328 *	Interface to various network functions.
329 */
330
331static inline void
332set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
333{
334	sin->sin_family = AF_INET;
335	sin->sin_addr.s_addr = addr;
336	sin->sin_port = port;
337}
338
339/*
340 *	Set up interface addresses and routes.
341 */
342
343static int __init ic_setup_if(void)
344{
345	struct ifreq ir;
346	struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
347	int err;
348
349	memset(&ir, 0, sizeof(ir));
350	strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
351	set_sockaddr(sin, ic_myaddr, 0);
352	if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) {
353		pr_err("IP-Config: Unable to set interface address (%d)\n",
354		       err);
355		return -1;
356	}
357	set_sockaddr(sin, ic_netmask, 0);
358	if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) {
359		pr_err("IP-Config: Unable to set interface netmask (%d)\n",
360		       err);
361		return -1;
362	}
363	set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
364	if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) {
365		pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
366		       err);
367		return -1;
368	}
369	/* Handle the case where we need non-standard MTU on the boot link (a network
370	 * using jumbo frames, for instance).  If we can't set the mtu, don't error
371	 * out, we'll try to muddle along.
372	 */
373	if (ic_dev_mtu != 0) {
374		rtnl_lock();
375		if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0)
376			pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
377			       ic_dev_mtu, err);
378		rtnl_unlock();
379	}
380	return 0;
381}
382
383static int __init ic_setup_routes(void)
384{
385	/* No need to setup device routes, only the default route... */
386
387	if (ic_gateway != NONE) {
388		struct rtentry rm;
389		int err;
390
391		memset(&rm, 0, sizeof(rm));
392		if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
393			pr_err("IP-Config: Gateway not on directly connected network\n");
394			return -1;
395		}
396		set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
397		set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
398		set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
399		rm.rt_flags = RTF_UP | RTF_GATEWAY;
400		if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) {
401			pr_err("IP-Config: Cannot add default route (%d)\n",
402			       err);
403			return -1;
404		}
405	}
406
407	return 0;
408}
409
410/*
411 *	Fill in default values for all missing parameters.
412 */
413
414static int __init ic_defaults(void)
415{
416	/*
417	 *	At this point we have no userspace running so need not
418	 *	claim locks on system_utsname
419	 */
420
421	if (!ic_host_name_set)
422		sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
423
424	if (root_server_addr == NONE)
425		root_server_addr = ic_servaddr;
426
427	if (ic_netmask == NONE) {
428		if (IN_CLASSA(ntohl(ic_myaddr)))
429			ic_netmask = htonl(IN_CLASSA_NET);
430		else if (IN_CLASSB(ntohl(ic_myaddr)))
431			ic_netmask = htonl(IN_CLASSB_NET);
432		else if (IN_CLASSC(ntohl(ic_myaddr)))
433			ic_netmask = htonl(IN_CLASSC_NET);
434		else if (IN_CLASSE(ntohl(ic_myaddr)))
435			ic_netmask = htonl(IN_CLASSE_NET);
436		else {
437			pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
438			       &ic_myaddr);
439			return -1;
440		}
441		pr_notice("IP-Config: Guessing netmask %pI4\n",
442			  &ic_netmask);
443	}
444
445	return 0;
446}
447
448/*
449 *	RARP support.
450 */
451
452#ifdef IPCONFIG_RARP
453
454static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
455
456static struct packet_type rarp_packet_type __initdata = {
457	.type =	cpu_to_be16(ETH_P_RARP),
458	.func =	ic_rarp_recv,
459};
460
461static inline void __init ic_rarp_init(void)
462{
463	dev_add_pack(&rarp_packet_type);
464}
465
466static inline void __init ic_rarp_cleanup(void)
467{
468	dev_remove_pack(&rarp_packet_type);
469}
470
471/*
472 *  Process received RARP packet.
473 */
474static int __init
475ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
476{
477	struct arphdr *rarp;
478	unsigned char *rarp_ptr;
479	__be32 sip, tip;
480	unsigned char *tha;		/* t for "target" */
481	struct ic_device *d;
482
483	if (!net_eq(dev_net(dev), &init_net))
484		goto drop;
485
486	skb = skb_share_check(skb, GFP_ATOMIC);
487	if (!skb)
488		return NET_RX_DROP;
489
490	if (!pskb_may_pull(skb, sizeof(struct arphdr)))
491		goto drop;
492
493	/* Basic sanity checks can be done without the lock.  */
494	rarp = (struct arphdr *)skb_transport_header(skb);
495
496	/* If this test doesn't pass, it's not IP, or we should
497	 * ignore it anyway.
498	 */
499	if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
500		goto drop;
501
502	/* If it's not a RARP reply, delete it. */
503	if (rarp->ar_op != htons(ARPOP_RREPLY))
504		goto drop;
505
506	/* If it's not Ethernet, delete it. */
507	if (rarp->ar_pro != htons(ETH_P_IP))
508		goto drop;
509
510	if (!pskb_may_pull(skb, arp_hdr_len(dev)))
511		goto drop;
512
513	/* OK, it is all there and looks valid, process... */
514	rarp = (struct arphdr *)skb_transport_header(skb);
515	rarp_ptr = (unsigned char *) (rarp + 1);
516
517	/* One reply at a time, please. */
518	spin_lock(&ic_recv_lock);
519
520	/* If we already have a reply, just drop the packet */
521	if (ic_got_reply)
522		goto drop_unlock;
523
524	/* Find the ic_device that the packet arrived on */
525	d = ic_first_dev;
526	while (d && d->dev != dev)
527		d = d->next;
528	if (!d)
529		goto drop_unlock;	/* should never happen */
530
531	/* Extract variable-width fields */
532	rarp_ptr += dev->addr_len;
533	memcpy(&sip, rarp_ptr, 4);
534	rarp_ptr += 4;
535	tha = rarp_ptr;
536	rarp_ptr += dev->addr_len;
537	memcpy(&tip, rarp_ptr, 4);
538
539	/* Discard packets which are not meant for us. */
540	if (memcmp(tha, dev->dev_addr, dev->addr_len))
541		goto drop_unlock;
542
543	/* Discard packets which are not from specified server. */
544	if (ic_servaddr != NONE && ic_servaddr != sip)
545		goto drop_unlock;
546
547	/* We have a winner! */
548	ic_dev = d;
549	if (ic_myaddr == NONE)
550		ic_myaddr = tip;
551	ic_servaddr = sip;
552	ic_addrservaddr = sip;
553	ic_got_reply = IC_RARP;
554
555drop_unlock:
556	/* Show's over.  Nothing to see here.  */
557	spin_unlock(&ic_recv_lock);
558
559drop:
560	/* Throw the packet out. */
561	kfree_skb(skb);
562	return 0;
563}
564
565
566/*
567 *  Send RARP request packet over a single interface.
568 */
569static void __init ic_rarp_send_if(struct ic_device *d)
570{
571	struct net_device *dev = d->dev;
572	arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
573		 dev->dev_addr, dev->dev_addr);
574}
575#endif
576
577/*
578 *  Predefine Nameservers
579 */
580static inline void __init ic_nameservers_predef(void)
581{
582	int i;
583
584	for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
585		ic_nameservers[i] = NONE;
586}
587
588/* Predefine NTP servers */
589static inline void __init ic_ntp_servers_predef(void)
590{
591	int i;
592
593	for (i = 0; i < CONF_NTP_SERVERS_MAX; i++)
594		ic_ntp_servers[i] = NONE;
595}
596
597/*
598 *	DHCP/BOOTP support.
599 */
600
601#ifdef IPCONFIG_BOOTP
602
603struct bootp_pkt {		/* BOOTP packet format */
604	struct iphdr iph;	/* IP header */
605	struct udphdr udph;	/* UDP header */
606	u8 op;			/* 1=request, 2=reply */
607	u8 htype;		/* HW address type */
608	u8 hlen;		/* HW address length */
609	u8 hops;		/* Used only by gateways */
610	__be32 xid;		/* Transaction ID */
611	__be16 secs;		/* Seconds since we started */
612	__be16 flags;		/* Just what it says */
613	__be32 client_ip;		/* Client's IP address if known */
614	__be32 your_ip;		/* Assigned IP address */
615	__be32 server_ip;		/* (Next, e.g. NFS) Server's IP address */
616	__be32 relay_ip;		/* IP address of BOOTP relay */
617	u8 hw_addr[16];		/* Client's HW address */
618	u8 serv_name[64];	/* Server host name */
619	u8 boot_file[128];	/* Name of boot file */
620	u8 exten[312];		/* DHCP options / BOOTP vendor extensions */
621};
622
623/* packet ops */
624#define BOOTP_REQUEST	1
625#define BOOTP_REPLY	2
626
627/* DHCP message types */
628#define DHCPDISCOVER	1
629#define DHCPOFFER	2
630#define DHCPREQUEST	3
631#define DHCPDECLINE	4
632#define DHCPACK		5
633#define DHCPNAK		6
634#define DHCPRELEASE	7
635#define DHCPINFORM	8
636
637static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
638
639static struct packet_type bootp_packet_type __initdata = {
640	.type =	cpu_to_be16(ETH_P_IP),
641	.func =	ic_bootp_recv,
642};
643
644/*
645 *  Initialize DHCP/BOOTP extension fields in the request.
646 */
647
648static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
649
650#ifdef IPCONFIG_DHCP
651
652static void __init
653ic_dhcp_init_options(u8 *options, struct ic_device *d)
654{
655	u8 mt = ((ic_servaddr == NONE)
656		 ? DHCPDISCOVER : DHCPREQUEST);
657	u8 *e = options;
658	int len;
659
660	pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
661
662	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
663	e += 4;
664
665	*e++ = 53;		/* DHCP message type */
666	*e++ = 1;
667	*e++ = mt;
668
669	if (mt == DHCPREQUEST) {
670		*e++ = 54;	/* Server ID (IP address) */
671		*e++ = 4;
672		memcpy(e, &ic_servaddr, 4);
673		e += 4;
674
675		*e++ = 50;	/* Requested IP address */
676		*e++ = 4;
677		memcpy(e, &ic_myaddr, 4);
678		e += 4;
679	}
680
681	/* always? */
682	{
683		static const u8 ic_req_params[] = {
684			1,	/* Subnet mask */
685			3,	/* Default gateway */
686			6,	/* DNS server */
687			12,	/* Host name */
688			15,	/* Domain name */
689			17,	/* Boot path */
690			26,	/* MTU */
691			40,	/* NIS domain name */
692			42,	/* NTP servers */
693		};
694
695		*e++ = 55;	/* Parameter request list */
696		*e++ = sizeof(ic_req_params);
697		memcpy(e, ic_req_params, sizeof(ic_req_params));
698		e += sizeof(ic_req_params);
699
700		if (ic_host_name_set) {
701			*e++ = 12;	/* host-name */
702			len = strlen(utsname()->nodename);
703			*e++ = len;
704			memcpy(e, utsname()->nodename, len);
705			e += len;
706		}
707		if (*vendor_class_identifier) {
708			pr_info("DHCP: sending class identifier \"%s\"\n",
709				vendor_class_identifier);
710			*e++ = 60;	/* Class-identifier */
711			len = strlen(vendor_class_identifier);
712			*e++ = len;
713			memcpy(e, vendor_class_identifier, len);
714			e += len;
715		}
716		len = strlen(dhcp_client_identifier + 1);
717		/* the minimum length of identifier is 2, include 1 byte type,
718		 * and can not be larger than the length of options
719		 */
720		if (len >= 1 && len < 312 - (e - options) - 1) {
721			*e++ = 61;
722			*e++ = len + 1;
723			memcpy(e, dhcp_client_identifier, len + 1);
724			e += len + 1;
725		}
726	}
727
728	*e++ = 255;	/* End of the list */
729}
730
731#endif /* IPCONFIG_DHCP */
732
733static void __init ic_bootp_init_ext(u8 *e)
734{
735	memcpy(e, ic_bootp_cookie, 4);	/* RFC1048 Magic Cookie */
736	e += 4;
737	*e++ = 1;		/* Subnet mask request */
738	*e++ = 4;
739	e += 4;
740	*e++ = 3;		/* Default gateway request */
741	*e++ = 4;
742	e += 4;
743#if CONF_NAMESERVERS_MAX > 0
744	*e++ = 6;		/* (DNS) name server request */
745	*e++ = 4 * CONF_NAMESERVERS_MAX;
746	e += 4 * CONF_NAMESERVERS_MAX;
747#endif
748	*e++ = 12;		/* Host name request */
749	*e++ = 32;
750	e += 32;
751	*e++ = 40;		/* NIS Domain name request */
752	*e++ = 32;
753	e += 32;
754	*e++ = 17;		/* Boot path */
755	*e++ = 40;
756	e += 40;
757
758	*e++ = 57;		/* set extension buffer size for reply */
759	*e++ = 2;
760	*e++ = 1;		/* 128+236+8+20+14, see dhcpd sources */
761	*e++ = 150;
762
763	*e++ = 255;		/* End of the list */
764}
765
766
767/*
768 *  Initialize the DHCP/BOOTP mechanism.
769 */
770static inline void __init ic_bootp_init(void)
771{
772	/* Re-initialise all name servers and NTP servers to NONE, in case any
773	 * were set via the "ip=" or "nfsaddrs=" kernel command line parameters:
774	 * any IP addresses specified there will already have been decoded but
775	 * are no longer needed
776	 */
777	ic_nameservers_predef();
778	ic_ntp_servers_predef();
779
780	dev_add_pack(&bootp_packet_type);
781}
782
783
784/*
785 *  DHCP/BOOTP cleanup.
786 */
787static inline void __init ic_bootp_cleanup(void)
788{
789	dev_remove_pack(&bootp_packet_type);
790}
791
792
793/*
794 *  Send DHCP/BOOTP request to single interface.
795 */
796static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
797{
798	struct net_device *dev = d->dev;
799	struct sk_buff *skb;
800	struct bootp_pkt *b;
801	struct iphdr *h;
802	int hlen = LL_RESERVED_SPACE(dev);
803	int tlen = dev->needed_tailroom;
804
805	/* Allocate packet */
806	skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
807			GFP_KERNEL);
808	if (!skb)
809		return;
810	skb_reserve(skb, hlen);
811	b = skb_put_zero(skb, sizeof(struct bootp_pkt));
812
813	/* Construct IP header */
814	skb_reset_network_header(skb);
815	h = ip_hdr(skb);
816	h->version = 4;
817	h->ihl = 5;
818	h->tot_len = htons(sizeof(struct bootp_pkt));
819	h->frag_off = htons(IP_DF);
820	h->ttl = 64;
821	h->protocol = IPPROTO_UDP;
822	h->daddr = htonl(INADDR_BROADCAST);
823	h->check = ip_fast_csum((unsigned char *) h, h->ihl);
824
825	/* Construct UDP header */
826	b->udph.source = htons(68);
827	b->udph.dest = htons(67);
828	b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
829	/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
830
831	/* Construct DHCP/BOOTP header */
832	b->op = BOOTP_REQUEST;
833	if (dev->type < 256) /* check for false types */
834		b->htype = dev->type;
835	else if (dev->type == ARPHRD_FDDI)
836		b->htype = ARPHRD_ETHER;
837	else {
838		pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
839			dev->name);
840		b->htype = dev->type; /* can cause undefined behavior */
841	}
842
843	/* server_ip and your_ip address are both already zero per RFC2131 */
844	b->hlen = dev->addr_len;
845	memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
846	b->secs = htons(jiffies_diff / HZ);
847	b->xid = d->xid;
848
849	/* add DHCP options or BOOTP extensions */
850#ifdef IPCONFIG_DHCP
851	if (ic_proto_enabled & IC_USE_DHCP)
852		ic_dhcp_init_options(b->exten, d);
853	else
854#endif
855		ic_bootp_init_ext(b->exten);
856
857	/* Chain packet down the line... */
858	skb->dev = dev;
859	skb->protocol = htons(ETH_P_IP);
860	if (dev_hard_header(skb, dev, ntohs(skb->protocol),
861			    dev->broadcast, dev->dev_addr, skb->len) < 0) {
862		kfree_skb(skb);
863		printk("E");
864		return;
865	}
866
867	if (dev_queue_xmit(skb) < 0)
868		printk("E");
869}
870
871
872/*
873 *  Copy BOOTP-supplied string
874 */
875static int __init ic_bootp_string(char *dest, char *src, int len, int max)
876{
877	if (!len)
878		return 0;
879	if (len > max-1)
880		len = max-1;
881	memcpy(dest, src, len);
882	dest[len] = '\0';
883	return 1;
884}
885
886
887/*
888 *  Process BOOTP extensions.
889 */
890static void __init ic_do_bootp_ext(u8 *ext)
891{
892	u8 servers;
893	int i;
894	__be16 mtu;
895
896	u8 *c;
897
898	pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
899	for (c=ext+2; c<ext+2+ext[1]; c++)
900		pr_debug(" %02x", *c);
901	pr_debug("\n");
902
903	switch (*ext++) {
904	case 1:		/* Subnet mask */
905		if (ic_netmask == NONE)
906			memcpy(&ic_netmask, ext+1, 4);
907		break;
908	case 3:		/* Default gateway */
909		if (ic_gateway == NONE)
910			memcpy(&ic_gateway, ext+1, 4);
911		break;
912	case 6:		/* DNS server */
913		servers= *ext/4;
914		if (servers > CONF_NAMESERVERS_MAX)
915			servers = CONF_NAMESERVERS_MAX;
916		for (i = 0; i < servers; i++) {
917			if (ic_nameservers[i] == NONE)
918				memcpy(&ic_nameservers[i], ext+1+4*i, 4);
919		}
920		break;
921	case 12:	/* Host name */
922		if (!ic_host_name_set) {
923			ic_bootp_string(utsname()->nodename, ext+1, *ext,
924					__NEW_UTS_LEN);
925			ic_host_name_set = 1;
926		}
927		break;
928	case 15:	/* Domain name (DNS) */
929		if (!ic_domain[0])
930			ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
931		break;
932	case 17:	/* Root path */
933		if (!root_server_path[0])
934			ic_bootp_string(root_server_path, ext+1, *ext,
935					sizeof(root_server_path));
936		break;
937	case 26:	/* Interface MTU */
938		memcpy(&mtu, ext+1, sizeof(mtu));
939		ic_dev_mtu = ntohs(mtu);
940		break;
941	case 40:	/* NIS Domain name (_not_ DNS) */
942		ic_bootp_string(utsname()->domainname, ext+1, *ext,
943				__NEW_UTS_LEN);
944		break;
945	case 42:	/* NTP servers */
946		servers = *ext / 4;
947		if (servers > CONF_NTP_SERVERS_MAX)
948			servers = CONF_NTP_SERVERS_MAX;
949		for (i = 0; i < servers; i++) {
950			if (ic_ntp_servers[i] == NONE)
951				memcpy(&ic_ntp_servers[i], ext+1+4*i, 4);
952		}
953		break;
954	}
955}
956
957
958/*
959 *  Receive BOOTP reply.
960 */
961static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
962{
963	struct bootp_pkt *b;
964	struct iphdr *h;
965	struct ic_device *d;
966	int len, ext_len;
967
968	if (!net_eq(dev_net(dev), &init_net))
969		goto drop;
970
971	/* Perform verifications before taking the lock.  */
972	if (skb->pkt_type == PACKET_OTHERHOST)
973		goto drop;
974
975	skb = skb_share_check(skb, GFP_ATOMIC);
976	if (!skb)
977		return NET_RX_DROP;
978
979	if (!pskb_may_pull(skb,
980			   sizeof(struct iphdr) +
981			   sizeof(struct udphdr)))
982		goto drop;
983
984	b = (struct bootp_pkt *)skb_network_header(skb);
985	h = &b->iph;
986
987	if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
988		goto drop;
989
990	/* Fragments are not supported */
991	if (ip_is_fragment(h)) {
992		net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
993		goto drop;
994	}
995
996	if (skb->len < ntohs(h->tot_len))
997		goto drop;
998
999	if (ip_fast_csum((char *) h, h->ihl))
1000		goto drop;
1001
1002	if (b->udph.source != htons(67) || b->udph.dest != htons(68))
1003		goto drop;
1004
1005	if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1006		goto drop;
1007
1008	len = ntohs(b->udph.len) - sizeof(struct udphdr);
1009	ext_len = len - (sizeof(*b) -
1010			 sizeof(struct iphdr) -
1011			 sizeof(struct udphdr) -
1012			 sizeof(b->exten));
1013	if (ext_len < 0)
1014		goto drop;
1015
1016	/* Ok the front looks good, make sure we can get at the rest.  */
1017	if (!pskb_may_pull(skb, skb->len))
1018		goto drop;
1019
1020	b = (struct bootp_pkt *)skb_network_header(skb);
1021	h = &b->iph;
1022
1023	/* One reply at a time, please. */
1024	spin_lock(&ic_recv_lock);
1025
1026	/* If we already have a reply, just drop the packet */
1027	if (ic_got_reply)
1028		goto drop_unlock;
1029
1030	/* Find the ic_device that the packet arrived on */
1031	d = ic_first_dev;
1032	while (d && d->dev != dev)
1033		d = d->next;
1034	if (!d)
1035		goto drop_unlock;  /* should never happen */
1036
1037	/* Is it a reply to our BOOTP request? */
1038	if (b->op != BOOTP_REPLY ||
1039	    b->xid != d->xid) {
1040		net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1041				    d->dev->name, b->op, b->xid);
1042		goto drop_unlock;
1043	}
1044
1045	/* Parse extensions */
1046	if (ext_len >= 4 &&
1047	    !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1048		u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1049		u8 *ext;
1050
1051#ifdef IPCONFIG_DHCP
1052		if (ic_proto_enabled & IC_USE_DHCP) {
1053			__be32 server_id = NONE;
1054			int mt = 0;
1055
1056			ext = &b->exten[4];
1057			while (ext < end && *ext != 0xff) {
1058				u8 *opt = ext++;
1059				if (*opt == 0)	/* Padding */
1060					continue;
1061				ext += *ext + 1;
1062				if (ext >= end)
1063					break;
1064				switch (*opt) {
1065				case 53:	/* Message type */
1066					if (opt[1])
1067						mt = opt[2];
1068					break;
1069				case 54:	/* Server ID (IP address) */
1070					if (opt[1] >= 4)
1071						memcpy(&server_id, opt + 2, 4);
1072					break;
1073				}
1074			}
1075
1076			pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
1077
1078			switch (mt) {
1079			case DHCPOFFER:
1080				/* While in the process of accepting one offer,
1081				 * ignore all others.
1082				 */
1083				if (ic_myaddr != NONE)
1084					goto drop_unlock;
1085
1086				/* Let's accept that offer. */
1087				ic_myaddr = b->your_ip;
1088				ic_servaddr = server_id;
1089				pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1090					 &ic_myaddr, &b->iph.saddr);
1091				/* The DHCP indicated server address takes
1092				 * precedence over the bootp header one if
1093				 * they are different.
1094				 */
1095				if ((server_id != NONE) &&
1096				    (b->server_ip != server_id))
1097					b->server_ip = ic_servaddr;
1098				break;
1099
1100			case DHCPACK:
1101				if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1102					goto drop_unlock;
1103
1104				/* Yeah! */
1105				break;
1106
1107			default:
1108				/* Urque.  Forget it*/
1109				ic_myaddr = NONE;
1110				ic_servaddr = NONE;
1111				goto drop_unlock;
1112			}
1113
1114			ic_dhcp_msgtype = mt;
1115
1116		}
1117#endif /* IPCONFIG_DHCP */
1118
1119		ext = &b->exten[4];
1120		while (ext < end && *ext != 0xff) {
1121			u8 *opt = ext++;
1122			if (*opt == 0)	/* Padding */
1123				continue;
1124			ext += *ext + 1;
1125			if (ext < end)
1126				ic_do_bootp_ext(opt);
1127		}
1128	}
1129
1130	/* We have a winner! */
1131	ic_dev = d;
1132	ic_myaddr = b->your_ip;
1133	ic_servaddr = b->server_ip;
1134	ic_addrservaddr = b->iph.saddr;
1135	if (ic_gateway == NONE && b->relay_ip)
1136		ic_gateway = b->relay_ip;
1137	if (ic_nameservers[0] == NONE)
1138		ic_nameservers[0] = ic_servaddr;
1139	ic_got_reply = IC_BOOTP;
1140
1141drop_unlock:
1142	/* Show's over.  Nothing to see here.  */
1143	spin_unlock(&ic_recv_lock);
1144
1145drop:
1146	/* Throw the packet out. */
1147	kfree_skb(skb);
1148
1149	return 0;
1150}
1151
1152
1153#endif
1154
1155
1156/*
1157 *	Dynamic IP configuration -- DHCP, BOOTP, RARP.
1158 */
1159
1160#ifdef IPCONFIG_DYNAMIC
1161
1162static int __init ic_dynamic(void)
1163{
1164	int retries;
1165	struct ic_device *d;
1166	unsigned long start_jiffies, timeout, jiff;
1167	int do_bootp = ic_proto_have_if & IC_BOOTP;
1168	int do_rarp = ic_proto_have_if & IC_RARP;
1169
1170	/*
1171	 * If none of DHCP/BOOTP/RARP was selected, return with an error.
1172	 * This routine gets only called when some pieces of information
1173	 * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1174	 */
1175	if (!ic_proto_enabled) {
1176		pr_err("IP-Config: Incomplete network configuration information\n");
1177		return -1;
1178	}
1179
1180#ifdef IPCONFIG_BOOTP
1181	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1182		pr_err("DHCP/BOOTP: No suitable device found\n");
1183#endif
1184#ifdef IPCONFIG_RARP
1185	if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1186		pr_err("RARP: No suitable device found\n");
1187#endif
1188
1189	if (!ic_proto_have_if)
1190		/* Error message already printed */
1191		return -1;
1192
1193	/*
1194	 * Setup protocols
1195	 */
1196#ifdef IPCONFIG_BOOTP
1197	if (do_bootp)
1198		ic_bootp_init();
1199#endif
1200#ifdef IPCONFIG_RARP
1201	if (do_rarp)
1202		ic_rarp_init();
1203#endif
1204
1205	/*
1206	 * Send requests and wait, until we get an answer. This loop
1207	 * seems to be a terrible waste of CPU time, but actually there is
1208	 * only one process running at all, so we don't need to use any
1209	 * scheduler functions.
1210	 * [Actually we could now, but the nothing else running note still
1211	 *  applies.. - AC]
1212	 */
1213	pr_notice("Sending %s%s%s requests .",
1214		  do_bootp
1215		  ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1216		  (do_bootp && do_rarp) ? " and " : "",
1217		  do_rarp ? "RARP" : "");
1218
1219	start_jiffies = jiffies;
1220	d = ic_first_dev;
1221	retries = CONF_SEND_RETRIES;
1222	get_random_bytes(&timeout, sizeof(timeout));
1223	timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1224	for (;;) {
1225#ifdef IPCONFIG_BOOTP
1226		if (do_bootp && (d->able & IC_BOOTP))
1227			ic_bootp_send_if(d, jiffies - start_jiffies);
1228#endif
1229#ifdef IPCONFIG_RARP
1230		if (do_rarp && (d->able & IC_RARP))
1231			ic_rarp_send_if(d);
1232#endif
1233
1234		if (!d->next) {
1235			jiff = jiffies + timeout;
1236			while (time_before(jiffies, jiff) && !ic_got_reply)
1237				schedule_timeout_uninterruptible(1);
1238		}
1239#ifdef IPCONFIG_DHCP
1240		/* DHCP isn't done until we get a DHCPACK. */
1241		if ((ic_got_reply & IC_BOOTP) &&
1242		    (ic_proto_enabled & IC_USE_DHCP) &&
1243		    ic_dhcp_msgtype != DHCPACK) {
1244			ic_got_reply = 0;
1245			/* continue on device that got the reply */
1246			d = ic_dev;
1247			pr_cont(",");
1248			continue;
1249		}
1250#endif /* IPCONFIG_DHCP */
1251
1252		if (ic_got_reply) {
1253			pr_cont(" OK\n");
1254			break;
1255		}
1256
1257		if ((d = d->next))
1258			continue;
1259
1260		if (! --retries) {
1261			pr_cont(" timed out!\n");
1262			break;
1263		}
1264
1265		d = ic_first_dev;
1266
1267		timeout = timeout CONF_TIMEOUT_MULT;
1268		if (timeout > CONF_TIMEOUT_MAX)
1269			timeout = CONF_TIMEOUT_MAX;
1270
1271		pr_cont(".");
1272	}
1273
1274#ifdef IPCONFIG_BOOTP
1275	if (do_bootp)
1276		ic_bootp_cleanup();
1277#endif
1278#ifdef IPCONFIG_RARP
1279	if (do_rarp)
1280		ic_rarp_cleanup();
1281#endif
1282
1283	if (!ic_got_reply) {
1284		ic_myaddr = NONE;
1285		return -1;
1286	}
1287
1288	pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1289		((ic_got_reply & IC_RARP) ? "RARP"
1290		: (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1291		&ic_addrservaddr, &ic_myaddr);
1292
1293	return 0;
1294}
1295
1296#endif /* IPCONFIG_DYNAMIC */
1297
1298#ifdef CONFIG_PROC_FS
1299/* proc_dir_entry for /proc/net/ipconfig */
1300static struct proc_dir_entry *ipconfig_dir;
1301
1302/* Name servers: */
1303static int pnp_seq_show(struct seq_file *seq, void *v)
1304{
1305	int i;
1306
1307	if (ic_proto_used & IC_PROTO)
1308		seq_printf(seq, "#PROTO: %s\n",
1309			   (ic_proto_used & IC_RARP) ? "RARP"
1310			   : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1311	else
1312		seq_puts(seq, "#MANUAL\n");
1313
1314	if (ic_domain[0])
1315		seq_printf(seq,
1316			   "domain %s\n", ic_domain);
1317	for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1318		if (ic_nameservers[i] != NONE)
1319			seq_printf(seq, "nameserver %pI4\n",
1320				   &ic_nameservers[i]);
1321	}
1322	if (ic_servaddr != NONE)
1323		seq_printf(seq, "bootserver %pI4\n",
1324			   &ic_servaddr);
1325	return 0;
1326}
1327
1328/* Create the /proc/net/ipconfig directory */
1329static int __init ipconfig_proc_net_init(void)
1330{
1331	ipconfig_dir = proc_net_mkdir(&init_net, "ipconfig", init_net.proc_net);
1332	if (!ipconfig_dir)
1333		return -ENOMEM;
1334
1335	return 0;
1336}
1337
1338/* Create a new file under /proc/net/ipconfig */
1339static int ipconfig_proc_net_create(const char *name,
1340				    const struct proc_ops *proc_ops)
1341{
1342	char *pname;
1343	struct proc_dir_entry *p;
1344
1345	if (!ipconfig_dir)
1346		return -ENOMEM;
1347
1348	pname = kasprintf(GFP_KERNEL, "%s%s", "ipconfig/", name);
1349	if (!pname)
1350		return -ENOMEM;
1351
1352	p = proc_create(pname, 0444, init_net.proc_net, proc_ops);
1353	kfree(pname);
1354	if (!p)
1355		return -ENOMEM;
1356
1357	return 0;
1358}
1359
1360/* Write NTP server IP addresses to /proc/net/ipconfig/ntp_servers */
1361static int ntp_servers_show(struct seq_file *seq, void *v)
1362{
1363	int i;
1364
1365	for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1366		if (ic_ntp_servers[i] != NONE)
1367			seq_printf(seq, "%pI4\n", &ic_ntp_servers[i]);
1368	}
1369	return 0;
1370}
1371DEFINE_PROC_SHOW_ATTRIBUTE(ntp_servers);
1372#endif /* CONFIG_PROC_FS */
1373
1374/*
1375 *  Extract IP address from the parameter string if needed. Note that we
1376 *  need to have root_server_addr set _before_ IPConfig gets called as it
1377 *  can override it.
1378 */
1379__be32 __init root_nfs_parse_addr(char *name)
1380{
1381	__be32 addr;
1382	int octets = 0;
1383	char *cp, *cq;
1384
1385	cp = cq = name;
1386	while (octets < 4) {
1387		while (*cp >= '0' && *cp <= '9')
1388			cp++;
1389		if (cp == cq || cp - cq > 3)
1390			break;
1391		if (*cp == '.' || octets == 3)
1392			octets++;
1393		if (octets < 4)
1394			cp++;
1395		cq = cp;
1396	}
1397	if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1398		if (*cp == ':')
1399			*cp++ = '\0';
1400		addr = in_aton(name);
1401		memmove(name, cp, strlen(cp) + 1);
1402	} else
1403		addr = NONE;
1404
1405	return addr;
1406}
1407
1408#define DEVICE_WAIT_MAX		12 /* 12 seconds */
1409
1410static int __init wait_for_devices(void)
1411{
1412	int i;
1413
1414	for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1415		struct net_device *dev;
1416		int found = 0;
1417
1418		/* make sure deferred device probes are finished */
1419		wait_for_device_probe();
1420
1421		rtnl_lock();
1422		for_each_netdev(&init_net, dev) {
1423			if (ic_is_init_dev(dev)) {
1424				found = 1;
1425				break;
1426			}
1427		}
1428		rtnl_unlock();
1429		if (found)
1430			return 0;
1431		ssleep(1);
1432	}
1433	return -ENODEV;
1434}
1435
1436/*
1437 *	IP Autoconfig dispatcher.
1438 */
1439
1440static int __init ip_auto_config(void)
1441{
1442	__be32 addr;
1443#ifdef IPCONFIG_DYNAMIC
1444	int retries = CONF_OPEN_RETRIES;
1445#endif
1446	int err;
1447	unsigned int i, count;
1448
1449	/* Initialise all name servers and NTP servers to NONE (but only if the
1450	 * "ip=" or "nfsaddrs=" kernel command line parameters weren't decoded,
1451	 * otherwise we'll overwrite the IP addresses specified there)
1452	 */
1453	if (ic_set_manually == 0) {
1454		ic_nameservers_predef();
1455		ic_ntp_servers_predef();
1456	}
1457
1458#ifdef CONFIG_PROC_FS
1459	proc_create_single("pnp", 0444, init_net.proc_net, pnp_seq_show);
1460
1461	if (ipconfig_proc_net_init() == 0)
1462		ipconfig_proc_net_create("ntp_servers", &ntp_servers_proc_ops);
1463#endif /* CONFIG_PROC_FS */
1464
1465	if (!ic_enable)
1466		return 0;
1467
1468	pr_debug("IP-Config: Entered.\n");
1469#ifdef IPCONFIG_DYNAMIC
1470 try_try_again:
1471#endif
1472	/* Wait for devices to appear */
1473	err = wait_for_devices();
1474	if (err)
1475		return err;
1476
1477	/* Setup all network devices */
1478	err = ic_open_devs();
1479	if (err)
1480		return err;
1481
1482	/* Give drivers a chance to settle */
1483	msleep(CONF_POST_OPEN);
1484
1485	/*
1486	 * If the config information is insufficient (e.g., our IP address or
1487	 * IP address of the boot server is missing or we have multiple network
1488	 * interfaces and no default was set), use BOOTP or RARP to get the
1489	 * missing values.
1490	 */
1491	if (ic_myaddr == NONE ||
1492#if defined(CONFIG_ROOT_NFS) || defined(CONFIG_CIFS_ROOT)
1493	    (root_server_addr == NONE &&
1494	     ic_servaddr == NONE &&
1495	     (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) ||
1496#endif
1497	    ic_first_dev->next) {
1498#ifdef IPCONFIG_DYNAMIC
1499		if (ic_dynamic() < 0) {
1500			ic_close_devs();
1501
1502			/*
1503			 * I don't know why, but sometimes the
1504			 * eepro100 driver (at least) gets upset and
1505			 * doesn't work the first time it's opened.
1506			 * But then if you close it and reopen it, it
1507			 * works just fine.  So we need to try that at
1508			 * least once before giving up.
1509			 *
1510			 * Also, if the root will be NFS-mounted, we
1511			 * have nowhere to go if DHCP fails.  So we
1512			 * just have to keep trying forever.
1513			 *
1514			 * 				-- Chip
1515			 */
1516#ifdef CONFIG_ROOT_NFS
1517			if (ROOT_DEV ==  Root_NFS) {
1518				pr_err("IP-Config: Retrying forever (NFS root)...\n");
1519				goto try_try_again;
1520			}
1521#endif
1522#ifdef CONFIG_CIFS_ROOT
1523			if (ROOT_DEV == Root_CIFS) {
1524				pr_err("IP-Config: Retrying forever (CIFS root)...\n");
1525				goto try_try_again;
1526			}
1527#endif
1528
1529			if (--retries) {
1530				pr_err("IP-Config: Reopening network devices...\n");
1531				goto try_try_again;
1532			}
1533
1534			/* Oh, well.  At least we tried. */
1535			pr_err("IP-Config: Auto-configuration of network failed\n");
1536			return -1;
1537		}
1538#else /* !DYNAMIC */
1539		pr_err("IP-Config: Incomplete network configuration information\n");
1540		ic_close_devs();
1541		return -1;
1542#endif /* IPCONFIG_DYNAMIC */
1543	} else {
1544		/* Device selected manually or only one device -> use it */
1545		ic_dev = ic_first_dev;
1546	}
1547
1548	addr = root_nfs_parse_addr(root_server_path);
1549	if (root_server_addr == NONE)
1550		root_server_addr = addr;
1551
1552	/*
1553	 * Use defaults wherever applicable.
1554	 */
1555	if (ic_defaults() < 0)
1556		return -1;
1557
1558	/*
1559	 * Record which protocol was actually used.
1560	 */
1561#ifdef IPCONFIG_DYNAMIC
1562	ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1563#endif
1564
1565#ifndef IPCONFIG_SILENT
1566	/*
1567	 * Clue in the operator.
1568	 */
1569	pr_info("IP-Config: Complete:\n");
1570
1571	pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1572		ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1573		&ic_myaddr, &ic_netmask, &ic_gateway);
1574	pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1575		utsname()->nodename, ic_domain, utsname()->domainname);
1576	pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1577		&ic_servaddr, &root_server_addr, root_server_path);
1578	if (ic_dev_mtu)
1579		pr_cont(", mtu=%d", ic_dev_mtu);
1580	/* Name servers (if any): */
1581	for (i = 0, count = 0; i < CONF_NAMESERVERS_MAX; i++) {
1582		if (ic_nameservers[i] != NONE) {
1583			if (i == 0)
1584				pr_info("     nameserver%u=%pI4",
1585					i, &ic_nameservers[i]);
1586			else
1587				pr_cont(", nameserver%u=%pI4",
1588					i, &ic_nameservers[i]);
1589
1590			count++;
1591		}
1592		if ((i + 1 == CONF_NAMESERVERS_MAX) && count > 0)
1593			pr_cont("\n");
1594	}
1595	/* NTP servers (if any): */
1596	for (i = 0, count = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1597		if (ic_ntp_servers[i] != NONE) {
1598			if (i == 0)
1599				pr_info("     ntpserver%u=%pI4",
1600					i, &ic_ntp_servers[i]);
1601			else
1602				pr_cont(", ntpserver%u=%pI4",
1603					i, &ic_ntp_servers[i]);
1604
1605			count++;
1606		}
1607		if ((i + 1 == CONF_NTP_SERVERS_MAX) && count > 0)
1608			pr_cont("\n");
1609	}
1610#endif /* !SILENT */
1611
1612	/*
1613	 * Close all network devices except the device we've
1614	 * autoconfigured and set up routes.
1615	 */
1616	if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1617		err = -1;
1618	else
1619		err = 0;
1620
1621	ic_close_devs();
1622
1623	return err;
1624}
1625
1626late_initcall(ip_auto_config);
1627
1628
1629/*
1630 *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1631 *  command line parameter.  See Documentation/admin-guide/nfs/nfsroot.rst.
1632 */
1633static int __init ic_proto_name(char *name)
1634{
1635	if (!strcmp(name, "on") || !strcmp(name, "any")) {
1636		return 1;
1637	}
1638	if (!strcmp(name, "off") || !strcmp(name, "none")) {
1639		return 0;
1640	}
1641#ifdef CONFIG_IP_PNP_DHCP
1642	else if (!strncmp(name, "dhcp", 4)) {
1643		char *client_id;
1644
1645		ic_proto_enabled &= ~IC_RARP;
1646		client_id = strstr(name, "dhcp,");
1647		if (client_id) {
1648			char *v;
1649
1650			client_id = client_id + 5;
1651			v = strchr(client_id, ',');
1652			if (!v)
1653				return 1;
1654			*v = 0;
1655			if (kstrtou8(client_id, 0, dhcp_client_identifier))
1656				pr_debug("DHCP: Invalid client identifier type\n");
1657			strncpy(dhcp_client_identifier + 1, v + 1, 251);
1658			*v = ',';
1659		}
1660		return 1;
1661	}
1662#endif
1663#ifdef CONFIG_IP_PNP_BOOTP
1664	else if (!strcmp(name, "bootp")) {
1665		ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1666		return 1;
1667	}
1668#endif
1669#ifdef CONFIG_IP_PNP_RARP
1670	else if (!strcmp(name, "rarp")) {
1671		ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1672		return 1;
1673	}
1674#endif
1675#ifdef IPCONFIG_DYNAMIC
1676	else if (!strcmp(name, "both")) {
1677		ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1678		return 1;
1679	}
1680#endif
1681	return 0;
1682}
1683
1684static int __init ip_auto_config_setup(char *addrs)
1685{
1686	char *cp, *ip, *dp;
1687	int num = 0;
1688
1689	ic_set_manually = 1;
1690	ic_enable = 1;
1691
1692	/*
1693	 * If any dhcp, bootp etc options are set, leave autoconfig on
1694	 * and skip the below static IP processing.
1695	 */
1696	if (ic_proto_name(addrs))
1697		return 1;
1698
1699	/* If no static IP is given, turn off autoconfig and bail.  */
1700	if (*addrs == 0 ||
1701	    strcmp(addrs, "off") == 0 ||
1702	    strcmp(addrs, "none") == 0) {
1703		ic_enable = 0;
1704		return 1;
1705	}
1706
1707	/* Initialise all name servers and NTP servers to NONE */
1708	ic_nameservers_predef();
1709	ic_ntp_servers_predef();
1710
1711	/* Parse string for static IP assignment.  */
1712	ip = addrs;
1713	while (ip && *ip) {
1714		if ((cp = strchr(ip, ':')))
1715			*cp++ = '\0';
1716		if (strlen(ip) > 0) {
1717			pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1718			switch (num) {
1719			case 0:
1720				if ((ic_myaddr = in_aton(ip)) == ANY)
1721					ic_myaddr = NONE;
1722				break;
1723			case 1:
1724				if ((ic_servaddr = in_aton(ip)) == ANY)
1725					ic_servaddr = NONE;
1726				break;
1727			case 2:
1728				if ((ic_gateway = in_aton(ip)) == ANY)
1729					ic_gateway = NONE;
1730				break;
1731			case 3:
1732				if ((ic_netmask = in_aton(ip)) == ANY)
1733					ic_netmask = NONE;
1734				break;
1735			case 4:
1736				if ((dp = strchr(ip, '.'))) {
1737					*dp++ = '\0';
1738					strlcpy(utsname()->domainname, dp,
1739						sizeof(utsname()->domainname));
1740				}
1741				strlcpy(utsname()->nodename, ip,
1742					sizeof(utsname()->nodename));
1743				ic_host_name_set = 1;
1744				break;
1745			case 5:
1746				strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1747				break;
1748			case 6:
1749				if (ic_proto_name(ip) == 0 &&
1750				    ic_myaddr == NONE) {
1751					ic_enable = 0;
1752				}
1753				break;
1754			case 7:
1755				if (CONF_NAMESERVERS_MAX >= 1) {
1756					ic_nameservers[0] = in_aton(ip);
1757					if (ic_nameservers[0] == ANY)
1758						ic_nameservers[0] = NONE;
1759				}
1760				break;
1761			case 8:
1762				if (CONF_NAMESERVERS_MAX >= 2) {
1763					ic_nameservers[1] = in_aton(ip);
1764					if (ic_nameservers[1] == ANY)
1765						ic_nameservers[1] = NONE;
1766				}
1767				break;
1768			case 9:
1769				if (CONF_NTP_SERVERS_MAX >= 1) {
1770					ic_ntp_servers[0] = in_aton(ip);
1771					if (ic_ntp_servers[0] == ANY)
1772						ic_ntp_servers[0] = NONE;
1773				}
1774				break;
1775			}
1776		}
1777		ip = cp;
1778		num++;
1779	}
1780
1781	return 1;
1782}
1783__setup("ip=", ip_auto_config_setup);
1784
1785static int __init nfsaddrs_config_setup(char *addrs)
1786{
1787	return ip_auto_config_setup(addrs);
1788}
1789__setup("nfsaddrs=", nfsaddrs_config_setup);
1790
1791static int __init vendor_class_identifier_setup(char *addrs)
1792{
1793	if (strlcpy(vendor_class_identifier, addrs,
1794		    sizeof(vendor_class_identifier))
1795	    >= sizeof(vendor_class_identifier))
1796		pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1797			vendor_class_identifier);
1798	return 1;
1799}
1800__setup("dhcpclass=", vendor_class_identifier_setup);
1801
1802static int __init set_carrier_timeout(char *str)
1803{
1804	ssize_t ret;
1805
1806	if (!str)
1807		return 0;
1808
1809	ret = kstrtouint(str, 0, &carrier_timeout);
1810	if (ret)
1811		return 0;
1812
1813	return 1;
1814}
1815__setup("carrier_timeout=", set_carrier_timeout);
1816