Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[linux-2.6.git] / net / ipv4 / ipconfig.c
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 <net/net_namespace.h>
58 #include <net/arp.h>
59 #include <net/ip.h>
60 #include <net/ipconfig.h>
61 #include <net/route.h>
62
63 #include <asm/uaccess.h>
64 #include <net/checksum.h>
65 #include <asm/processor.h>
66
67 /* Define this to allow debugging output */
68 #undef IPCONFIG_DEBUG
69
70 #ifdef IPCONFIG_DEBUG
71 #define DBG(x) printk x
72 #else
73 #define DBG(x) do { } while(0)
74 #endif
75
76 #if defined(CONFIG_IP_PNP_DHCP)
77 #define IPCONFIG_DHCP
78 #endif
79 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
80 #define IPCONFIG_BOOTP
81 #endif
82 #if defined(CONFIG_IP_PNP_RARP)
83 #define IPCONFIG_RARP
84 #endif
85 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
86 #define IPCONFIG_DYNAMIC
87 #endif
88
89 /* Define the friendly delay before and after opening net devices */
90 #define CONF_PRE_OPEN           500     /* Before opening: 1/2 second */
91 #define CONF_POST_OPEN          1       /* After opening: 1 second */
92
93 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
94 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
95 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
96 #define CONF_INTER_TIMEOUT      (HZ/2)  /* Inter-device timeout: 1/2 second */
97 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
98 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
99 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
100 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
101 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
102                                            - '3' from resolv.h */
103
104 #define NONE cpu_to_be32(INADDR_NONE)
105 #define ANY cpu_to_be32(INADDR_ANY)
106
107 /*
108  * Public IP configuration
109  */
110
111 /* This is used by platforms which might be able to set the ipconfig
112  * variables using firmware environment vars.  If this is set, it will
113  * ignore such firmware variables.
114  */
115 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
116
117 static int ic_enable __initdata = 0;            /* IP config enabled? */
118
119 /* Protocol choice */
120 int ic_proto_enabled __initdata = 0
121 #ifdef IPCONFIG_BOOTP
122                         | IC_BOOTP
123 #endif
124 #ifdef CONFIG_IP_PNP_DHCP
125                         | IC_USE_DHCP
126 #endif
127 #ifdef IPCONFIG_RARP
128                         | IC_RARP
129 #endif
130                         ;
131
132 static int ic_host_name_set __initdata = 0;     /* Host name set by us? */
133
134 __be32 ic_myaddr = NONE;                /* My IP address */
135 static __be32 ic_netmask = NONE;        /* Netmask for local subnet */
136 __be32 ic_gateway = NONE;       /* Gateway IP address */
137
138 __be32 ic_servaddr = NONE;      /* Boot server IP address */
139
140 __be32 root_server_addr = NONE; /* Address of NFS server */
141 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
142
143 u32 ic_dev_xid;         /* Device under configuration */
144
145 /* vendor class identifier */
146 static char vendor_class_identifier[253] __initdata;
147
148 /* Persistent data: */
149
150 static int ic_proto_used;                       /* Protocol used, if any */
151 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
152 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
153
154 /*
155  * Private state.
156  */
157
158 /* Name of user-selected boot device */
159 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
160
161 /* Protocols supported by available interfaces */
162 static int ic_proto_have_if __initdata = 0;
163
164 /* MTU for boot device */
165 static int ic_dev_mtu __initdata = 0;
166
167 #ifdef IPCONFIG_DYNAMIC
168 static DEFINE_SPINLOCK(ic_recv_lock);
169 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
170 #endif
171 #ifdef IPCONFIG_DHCP
172 static int ic_dhcp_msgtype __initdata = 0;      /* DHCP msg type received */
173 #endif
174
175
176 /*
177  *      Network devices
178  */
179
180 struct ic_device {
181         struct ic_device *next;
182         struct net_device *dev;
183         unsigned short flags;
184         short able;
185         __be32 xid;
186 };
187
188 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
189 static struct net_device *ic_dev __initdata = NULL;     /* Selected device */
190
191 static bool __init ic_device_match(struct net_device *dev)
192 {
193         if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
194             (!(dev->flags & IFF_LOOPBACK) &&
195              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
196              strncmp(dev->name, "dummy", 5)))
197                 return true;
198         return false;
199 }
200
201 static int __init ic_open_devs(void)
202 {
203         struct ic_device *d, **last;
204         struct net_device *dev;
205         unsigned short oflags;
206
207         last = &ic_first_dev;
208         rtnl_lock();
209
210         /* bring loopback device up first */
211         for_each_netdev(&init_net, dev) {
212                 if (!(dev->flags & IFF_LOOPBACK))
213                         continue;
214                 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
215                         printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
216         }
217
218         for_each_netdev(&init_net, dev) {
219                 if (dev->flags & IFF_LOOPBACK)
220                         continue;
221                 if (ic_device_match(dev)) {
222                         int able = 0;
223                         if (dev->mtu >= 364)
224                                 able |= IC_BOOTP;
225                         else
226                                 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
227                         if (!(dev->flags & IFF_NOARP))
228                                 able |= IC_RARP;
229                         able &= ic_proto_enabled;
230                         if (ic_proto_enabled && !able)
231                                 continue;
232                         oflags = dev->flags;
233                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
234                                 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
235                                 continue;
236                         }
237                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
238                                 rtnl_unlock();
239                                 return -ENOMEM;
240                         }
241                         d->dev = dev;
242                         *last = d;
243                         last = &d->next;
244                         d->flags = oflags;
245                         d->able = able;
246                         if (able & IC_BOOTP)
247                                 get_random_bytes(&d->xid, sizeof(__be32));
248                         else
249                                 d->xid = 0;
250                         ic_proto_have_if |= able;
251                         DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
252                                 dev->name, able, d->xid));
253                 }
254         }
255         rtnl_unlock();
256
257         *last = NULL;
258
259         if (!ic_first_dev) {
260                 if (user_dev_name[0])
261                         printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
262                 else
263                         printk(KERN_ERR "IP-Config: No network devices available.\n");
264                 return -ENODEV;
265         }
266         return 0;
267 }
268
269 static void __init ic_close_devs(void)
270 {
271         struct ic_device *d, *next;
272         struct net_device *dev;
273
274         rtnl_lock();
275         next = ic_first_dev;
276         while ((d = next)) {
277                 next = d->next;
278                 dev = d->dev;
279                 if (dev != ic_dev) {
280                         DBG(("IP-Config: Downing %s\n", dev->name));
281                         dev_change_flags(dev, d->flags);
282                 }
283                 kfree(d);
284         }
285         rtnl_unlock();
286 }
287
288 /*
289  *      Interface to various network functions.
290  */
291
292 static inline void
293 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
294 {
295         sin->sin_family = AF_INET;
296         sin->sin_addr.s_addr = addr;
297         sin->sin_port = port;
298 }
299
300 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
301 {
302         int res;
303
304         mm_segment_t oldfs = get_fs();
305         set_fs(get_ds());
306         res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
307         set_fs(oldfs);
308         return res;
309 }
310
311 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
312 {
313         int res;
314
315         mm_segment_t oldfs = get_fs();
316         set_fs(get_ds());
317         res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
318         set_fs(oldfs);
319         return res;
320 }
321
322 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
323 {
324         int res;
325
326         mm_segment_t oldfs = get_fs();
327         set_fs(get_ds());
328         res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
329         set_fs(oldfs);
330         return res;
331 }
332
333 /*
334  *      Set up interface addresses and routes.
335  */
336
337 static int __init ic_setup_if(void)
338 {
339         struct ifreq ir;
340         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
341         int err;
342
343         memset(&ir, 0, sizeof(ir));
344         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
345         set_sockaddr(sin, ic_myaddr, 0);
346         if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
347                 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
348                 return -1;
349         }
350         set_sockaddr(sin, ic_netmask, 0);
351         if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
352                 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
353                 return -1;
354         }
355         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
356         if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
357                 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
358                 return -1;
359         }
360         /* Handle the case where we need non-standard MTU on the boot link (a network
361          * using jumbo frames, for instance).  If we can't set the mtu, don't error
362          * out, we'll try to muddle along.
363          */
364         if (ic_dev_mtu != 0) {
365                 strcpy(ir.ifr_name, ic_dev->name);
366                 ir.ifr_mtu = ic_dev_mtu;
367                 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
368                         printk(KERN_ERR "IP-Config: Unable to set interface mtu to %d (%d).\n",
369                                          ic_dev_mtu, err);
370         }
371         return 0;
372 }
373
374 static int __init ic_setup_routes(void)
375 {
376         /* No need to setup device routes, only the default route... */
377
378         if (ic_gateway != NONE) {
379                 struct rtentry rm;
380                 int err;
381
382                 memset(&rm, 0, sizeof(rm));
383                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
384                         printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
385                         return -1;
386                 }
387                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
388                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
389                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
390                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
391                 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
392                         printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
393                         return -1;
394                 }
395         }
396
397         return 0;
398 }
399
400 /*
401  *      Fill in default values for all missing parameters.
402  */
403
404 static int __init ic_defaults(void)
405 {
406         /*
407          *      At this point we have no userspace running so need not
408          *      claim locks on system_utsname
409          */
410
411         if (!ic_host_name_set)
412                 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
413
414         if (root_server_addr == NONE)
415                 root_server_addr = ic_servaddr;
416
417         if (ic_netmask == NONE) {
418                 if (IN_CLASSA(ntohl(ic_myaddr)))
419                         ic_netmask = htonl(IN_CLASSA_NET);
420                 else if (IN_CLASSB(ntohl(ic_myaddr)))
421                         ic_netmask = htonl(IN_CLASSB_NET);
422                 else if (IN_CLASSC(ntohl(ic_myaddr)))
423                         ic_netmask = htonl(IN_CLASSC_NET);
424                 else {
425                         printk(KERN_ERR "IP-Config: Unable to guess netmask for address %pI4\n",
426                                 &ic_myaddr);
427                         return -1;
428                 }
429                 printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
430         }
431
432         return 0;
433 }
434
435 /*
436  *      RARP support.
437  */
438
439 #ifdef IPCONFIG_RARP
440
441 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
442
443 static struct packet_type rarp_packet_type __initdata = {
444         .type = cpu_to_be16(ETH_P_RARP),
445         .func = ic_rarp_recv,
446 };
447
448 static inline void __init ic_rarp_init(void)
449 {
450         dev_add_pack(&rarp_packet_type);
451 }
452
453 static inline void __init ic_rarp_cleanup(void)
454 {
455         dev_remove_pack(&rarp_packet_type);
456 }
457
458 /*
459  *  Process received RARP packet.
460  */
461 static int __init
462 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
463 {
464         struct arphdr *rarp;
465         unsigned char *rarp_ptr;
466         __be32 sip, tip;
467         unsigned char *sha, *tha;               /* s for "source", t for "target" */
468         struct ic_device *d;
469
470         if (!net_eq(dev_net(dev), &init_net))
471                 goto drop;
472
473         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
474                 return NET_RX_DROP;
475
476         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
477                 goto drop;
478
479         /* Basic sanity checks can be done without the lock.  */
480         rarp = (struct arphdr *)skb_transport_header(skb);
481
482         /* If this test doesn't pass, it's not IP, or we should
483          * ignore it anyway.
484          */
485         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
486                 goto drop;
487
488         /* If it's not a RARP reply, delete it. */
489         if (rarp->ar_op != htons(ARPOP_RREPLY))
490                 goto drop;
491
492         /* If it's not Ethernet, delete it. */
493         if (rarp->ar_pro != htons(ETH_P_IP))
494                 goto drop;
495
496         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
497                 goto drop;
498
499         /* OK, it is all there and looks valid, process... */
500         rarp = (struct arphdr *)skb_transport_header(skb);
501         rarp_ptr = (unsigned char *) (rarp + 1);
502
503         /* One reply at a time, please. */
504         spin_lock(&ic_recv_lock);
505
506         /* If we already have a reply, just drop the packet */
507         if (ic_got_reply)
508                 goto drop_unlock;
509
510         /* Find the ic_device that the packet arrived on */
511         d = ic_first_dev;
512         while (d && d->dev != dev)
513                 d = d->next;
514         if (!d)
515                 goto drop_unlock;       /* should never happen */
516
517         /* Extract variable-width fields */
518         sha = rarp_ptr;
519         rarp_ptr += dev->addr_len;
520         memcpy(&sip, rarp_ptr, 4);
521         rarp_ptr += 4;
522         tha = rarp_ptr;
523         rarp_ptr += dev->addr_len;
524         memcpy(&tip, rarp_ptr, 4);
525
526         /* Discard packets which are not meant for us. */
527         if (memcmp(tha, dev->dev_addr, dev->addr_len))
528                 goto drop_unlock;
529
530         /* Discard packets which are not from specified server. */
531         if (ic_servaddr != NONE && ic_servaddr != sip)
532                 goto drop_unlock;
533
534         /* We have a winner! */
535         ic_dev = dev;
536         if (ic_myaddr == NONE)
537                 ic_myaddr = tip;
538         ic_servaddr = sip;
539         ic_got_reply = IC_RARP;
540
541 drop_unlock:
542         /* Show's over.  Nothing to see here.  */
543         spin_unlock(&ic_recv_lock);
544
545 drop:
546         /* Throw the packet out. */
547         kfree_skb(skb);
548         return 0;
549 }
550
551
552 /*
553  *  Send RARP request packet over a single interface.
554  */
555 static void __init ic_rarp_send_if(struct ic_device *d)
556 {
557         struct net_device *dev = d->dev;
558         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
559                  dev->dev_addr, dev->dev_addr);
560 }
561 #endif
562
563 /*
564  *      DHCP/BOOTP support.
565  */
566
567 #ifdef IPCONFIG_BOOTP
568
569 struct bootp_pkt {              /* BOOTP packet format */
570         struct iphdr iph;       /* IP header */
571         struct udphdr udph;     /* UDP header */
572         u8 op;                  /* 1=request, 2=reply */
573         u8 htype;               /* HW address type */
574         u8 hlen;                /* HW address length */
575         u8 hops;                /* Used only by gateways */
576         __be32 xid;             /* Transaction ID */
577         __be16 secs;            /* Seconds since we started */
578         __be16 flags;           /* Just what it says */
579         __be32 client_ip;               /* Client's IP address if known */
580         __be32 your_ip;         /* Assigned IP address */
581         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
582         __be32 relay_ip;                /* IP address of BOOTP relay */
583         u8 hw_addr[16];         /* Client's HW address */
584         u8 serv_name[64];       /* Server host name */
585         u8 boot_file[128];      /* Name of boot file */
586         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
587 };
588
589 /* packet ops */
590 #define BOOTP_REQUEST   1
591 #define BOOTP_REPLY     2
592
593 /* DHCP message types */
594 #define DHCPDISCOVER    1
595 #define DHCPOFFER       2
596 #define DHCPREQUEST     3
597 #define DHCPDECLINE     4
598 #define DHCPACK         5
599 #define DHCPNAK         6
600 #define DHCPRELEASE     7
601 #define DHCPINFORM      8
602
603 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
604
605 static struct packet_type bootp_packet_type __initdata = {
606         .type = cpu_to_be16(ETH_P_IP),
607         .func = ic_bootp_recv,
608 };
609
610
611 /*
612  *  Initialize DHCP/BOOTP extension fields in the request.
613  */
614
615 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
616
617 #ifdef IPCONFIG_DHCP
618
619 static void __init
620 ic_dhcp_init_options(u8 *options)
621 {
622         u8 mt = ((ic_servaddr == NONE)
623                  ? DHCPDISCOVER : DHCPREQUEST);
624         u8 *e = options;
625         int len;
626
627 #ifdef IPCONFIG_DEBUG
628         printk("DHCP: Sending message type %d\n", mt);
629 #endif
630
631         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
632         e += 4;
633
634         *e++ = 53;              /* DHCP message type */
635         *e++ = 1;
636         *e++ = mt;
637
638         if (mt == DHCPREQUEST) {
639                 *e++ = 54;      /* Server ID (IP address) */
640                 *e++ = 4;
641                 memcpy(e, &ic_servaddr, 4);
642                 e += 4;
643
644                 *e++ = 50;      /* Requested IP address */
645                 *e++ = 4;
646                 memcpy(e, &ic_myaddr, 4);
647                 e += 4;
648         }
649
650         /* always? */
651         {
652                 static const u8 ic_req_params[] = {
653                         1,      /* Subnet mask */
654                         3,      /* Default gateway */
655                         6,      /* DNS server */
656                         12,     /* Host name */
657                         15,     /* Domain name */
658                         17,     /* Boot path */
659                         26,     /* MTU */
660                         40,     /* NIS domain name */
661                 };
662
663                 *e++ = 55;      /* Parameter request list */
664                 *e++ = sizeof(ic_req_params);
665                 memcpy(e, ic_req_params, sizeof(ic_req_params));
666                 e += sizeof(ic_req_params);
667
668                 if (*vendor_class_identifier) {
669                         printk(KERN_INFO "DHCP: sending class identifier \"%s\"\n",
670                                vendor_class_identifier);
671                         *e++ = 60;      /* Class-identifier */
672                         len = strlen(vendor_class_identifier);
673                         *e++ = len;
674                         memcpy(e, vendor_class_identifier, len);
675                         e += len;
676                 }
677         }
678
679         *e++ = 255;     /* End of the list */
680 }
681
682 #endif /* IPCONFIG_DHCP */
683
684 static void __init ic_bootp_init_ext(u8 *e)
685 {
686         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
687         e += 4;
688         *e++ = 1;               /* Subnet mask request */
689         *e++ = 4;
690         e += 4;
691         *e++ = 3;               /* Default gateway request */
692         *e++ = 4;
693         e += 4;
694         *e++ = 5;               /* Name server request */
695         *e++ = 8;
696         e += 8;
697         *e++ = 12;              /* Host name request */
698         *e++ = 32;
699         e += 32;
700         *e++ = 40;              /* NIS Domain name request */
701         *e++ = 32;
702         e += 32;
703         *e++ = 17;              /* Boot path */
704         *e++ = 40;
705         e += 40;
706
707         *e++ = 57;              /* set extension buffer size for reply */
708         *e++ = 2;
709         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
710         *e++ = 150;
711
712         *e++ = 255;             /* End of the list */
713 }
714
715
716 /*
717  *  Initialize the DHCP/BOOTP mechanism.
718  */
719 static inline void __init ic_bootp_init(void)
720 {
721         int i;
722
723         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
724                 ic_nameservers[i] = NONE;
725
726         dev_add_pack(&bootp_packet_type);
727 }
728
729
730 /*
731  *  DHCP/BOOTP cleanup.
732  */
733 static inline void __init ic_bootp_cleanup(void)
734 {
735         dev_remove_pack(&bootp_packet_type);
736 }
737
738
739 /*
740  *  Send DHCP/BOOTP request to single interface.
741  */
742 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
743 {
744         struct net_device *dev = d->dev;
745         struct sk_buff *skb;
746         struct bootp_pkt *b;
747         struct iphdr *h;
748
749         /* Allocate packet */
750         skb = alloc_skb(sizeof(struct bootp_pkt) + LL_ALLOCATED_SPACE(dev) + 15,
751                         GFP_KERNEL);
752         if (!skb)
753                 return;
754         skb_reserve(skb, LL_RESERVED_SPACE(dev));
755         b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
756         memset(b, 0, sizeof(struct bootp_pkt));
757
758         /* Construct IP header */
759         skb_reset_network_header(skb);
760         h = ip_hdr(skb);
761         h->version = 4;
762         h->ihl = 5;
763         h->tot_len = htons(sizeof(struct bootp_pkt));
764         h->frag_off = htons(IP_DF);
765         h->ttl = 64;
766         h->protocol = IPPROTO_UDP;
767         h->daddr = htonl(INADDR_BROADCAST);
768         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
769
770         /* Construct UDP header */
771         b->udph.source = htons(68);
772         b->udph.dest = htons(67);
773         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
774         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
775
776         /* Construct DHCP/BOOTP header */
777         b->op = BOOTP_REQUEST;
778         if (dev->type < 256) /* check for false types */
779                 b->htype = dev->type;
780         else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
781                 b->htype = ARPHRD_IEEE802;
782         else if (dev->type == ARPHRD_FDDI)
783                 b->htype = ARPHRD_ETHER;
784         else {
785                 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
786                 b->htype = dev->type; /* can cause undefined behavior */
787         }
788
789         /* server_ip and your_ip address are both already zero per RFC2131 */
790         b->hlen = dev->addr_len;
791         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
792         b->secs = htons(jiffies_diff / HZ);
793         b->xid = d->xid;
794
795         /* add DHCP options or BOOTP extensions */
796 #ifdef IPCONFIG_DHCP
797         if (ic_proto_enabled & IC_USE_DHCP)
798                 ic_dhcp_init_options(b->exten);
799         else
800 #endif
801                 ic_bootp_init_ext(b->exten);
802
803         /* Chain packet down the line... */
804         skb->dev = dev;
805         skb->protocol = htons(ETH_P_IP);
806         if (dev_hard_header(skb, dev, ntohs(skb->protocol),
807                             dev->broadcast, dev->dev_addr, skb->len) < 0 ||
808             dev_queue_xmit(skb) < 0)
809                 printk("E");
810 }
811
812
813 /*
814  *  Copy BOOTP-supplied string if not already set.
815  */
816 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
817 {
818         if (!len)
819                 return 0;
820         if (len > max-1)
821                 len = max-1;
822         memcpy(dest, src, len);
823         dest[len] = '\0';
824         return 1;
825 }
826
827
828 /*
829  *  Process BOOTP extensions.
830  */
831 static void __init ic_do_bootp_ext(u8 *ext)
832 {
833        u8 servers;
834        int i;
835         u16 mtu;
836
837 #ifdef IPCONFIG_DEBUG
838         u8 *c;
839
840         printk("DHCP/BOOTP: Got extension %d:",*ext);
841         for (c=ext+2; c<ext+2+ext[1]; c++)
842                 printk(" %02x", *c);
843         printk("\n");
844 #endif
845
846         switch (*ext++) {
847                 case 1:         /* Subnet mask */
848                         if (ic_netmask == NONE)
849                                 memcpy(&ic_netmask, ext+1, 4);
850                         break;
851                 case 3:         /* Default gateway */
852                         if (ic_gateway == NONE)
853                                 memcpy(&ic_gateway, ext+1, 4);
854                         break;
855                 case 6:         /* DNS server */
856                         servers= *ext/4;
857                         if (servers > CONF_NAMESERVERS_MAX)
858                                 servers = CONF_NAMESERVERS_MAX;
859                         for (i = 0; i < servers; i++) {
860                                 if (ic_nameservers[i] == NONE)
861                                         memcpy(&ic_nameservers[i], ext+1+4*i, 4);
862                         }
863                         break;
864                 case 12:        /* Host name */
865                         ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
866                         ic_host_name_set = 1;
867                         break;
868                 case 15:        /* Domain name (DNS) */
869                         ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
870                         break;
871                 case 17:        /* Root path */
872                         if (!root_server_path[0])
873                                 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
874                         break;
875                 case 26:        /* Interface MTU */
876                         memcpy(&mtu, ext+1, sizeof(mtu));
877                         ic_dev_mtu = ntohs(mtu);
878                         break;
879                 case 40:        /* NIS Domain name (_not_ DNS) */
880                         ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
881                         break;
882         }
883 }
884
885
886 /*
887  *  Receive BOOTP reply.
888  */
889 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
890 {
891         struct bootp_pkt *b;
892         struct iphdr *h;
893         struct ic_device *d;
894         int len, ext_len;
895
896         if (!net_eq(dev_net(dev), &init_net))
897                 goto drop;
898
899         /* Perform verifications before taking the lock.  */
900         if (skb->pkt_type == PACKET_OTHERHOST)
901                 goto drop;
902
903         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
904                 return NET_RX_DROP;
905
906         if (!pskb_may_pull(skb,
907                            sizeof(struct iphdr) +
908                            sizeof(struct udphdr)))
909                 goto drop;
910
911         b = (struct bootp_pkt *)skb_network_header(skb);
912         h = &b->iph;
913
914         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
915                 goto drop;
916
917         /* Fragments are not supported */
918         if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
919                 if (net_ratelimit())
920                         printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
921                                "reply.\n");
922                 goto drop;
923         }
924
925         if (skb->len < ntohs(h->tot_len))
926                 goto drop;
927
928         if (ip_fast_csum((char *) h, h->ihl))
929                 goto drop;
930
931         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
932                 goto drop;
933
934         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
935                 goto drop;
936
937         len = ntohs(b->udph.len) - sizeof(struct udphdr);
938         ext_len = len - (sizeof(*b) -
939                          sizeof(struct iphdr) -
940                          sizeof(struct udphdr) -
941                          sizeof(b->exten));
942         if (ext_len < 0)
943                 goto drop;
944
945         /* Ok the front looks good, make sure we can get at the rest.  */
946         if (!pskb_may_pull(skb, skb->len))
947                 goto drop;
948
949         b = (struct bootp_pkt *)skb_network_header(skb);
950         h = &b->iph;
951
952         /* One reply at a time, please. */
953         spin_lock(&ic_recv_lock);
954
955         /* If we already have a reply, just drop the packet */
956         if (ic_got_reply)
957                 goto drop_unlock;
958
959         /* Find the ic_device that the packet arrived on */
960         d = ic_first_dev;
961         while (d && d->dev != dev)
962                 d = d->next;
963         if (!d)
964                 goto drop_unlock;  /* should never happen */
965
966         /* Is it a reply to our BOOTP request? */
967         if (b->op != BOOTP_REPLY ||
968             b->xid != d->xid) {
969                 if (net_ratelimit())
970                         printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
971                                "op[%x] xid[%x]\n",
972                                b->op, b->xid);
973                 goto drop_unlock;
974         }
975
976         /* Is it a reply for the device we are configuring? */
977         if (b->xid != ic_dev_xid) {
978                 if (net_ratelimit())
979                         printk(KERN_ERR "DHCP/BOOTP: Ignoring delayed packet\n");
980                 goto drop_unlock;
981         }
982
983         /* Parse extensions */
984         if (ext_len >= 4 &&
985             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
986                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
987                 u8 *ext;
988
989 #ifdef IPCONFIG_DHCP
990                 if (ic_proto_enabled & IC_USE_DHCP) {
991                         __be32 server_id = NONE;
992                         int mt = 0;
993
994                         ext = &b->exten[4];
995                         while (ext < end && *ext != 0xff) {
996                                 u8 *opt = ext++;
997                                 if (*opt == 0)  /* Padding */
998                                         continue;
999                                 ext += *ext + 1;
1000                                 if (ext >= end)
1001                                         break;
1002                                 switch (*opt) {
1003                                 case 53:        /* Message type */
1004                                         if (opt[1])
1005                                                 mt = opt[2];
1006                                         break;
1007                                 case 54:        /* Server ID (IP address) */
1008                                         if (opt[1] >= 4)
1009                                                 memcpy(&server_id, opt + 2, 4);
1010                                         break;
1011                                 }
1012                         }
1013
1014 #ifdef IPCONFIG_DEBUG
1015                         printk("DHCP: Got message type %d\n", mt);
1016 #endif
1017
1018                         switch (mt) {
1019                         case DHCPOFFER:
1020                                 /* While in the process of accepting one offer,
1021                                  * ignore all others.
1022                                  */
1023                                 if (ic_myaddr != NONE)
1024                                         goto drop_unlock;
1025
1026                                 /* Let's accept that offer. */
1027                                 ic_myaddr = b->your_ip;
1028                                 ic_servaddr = server_id;
1029 #ifdef IPCONFIG_DEBUG
1030                                 printk("DHCP: Offered address %pI4 by server %pI4\n",
1031                                        &ic_myaddr, &ic_servaddr);
1032 #endif
1033                                 /* The DHCP indicated server address takes
1034                                  * precedence over the bootp header one if
1035                                  * they are different.
1036                                  */
1037                                 if ((server_id != NONE) &&
1038                                     (b->server_ip != server_id))
1039                                         b->server_ip = ic_servaddr;
1040                                 break;
1041
1042                         case DHCPACK:
1043                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1044                                         goto drop_unlock;
1045
1046                                 /* Yeah! */
1047                                 break;
1048
1049                         default:
1050                                 /* Urque.  Forget it*/
1051                                 ic_myaddr = NONE;
1052                                 ic_servaddr = NONE;
1053                                 goto drop_unlock;
1054                         }
1055
1056                         ic_dhcp_msgtype = mt;
1057
1058                 }
1059 #endif /* IPCONFIG_DHCP */
1060
1061                 ext = &b->exten[4];
1062                 while (ext < end && *ext != 0xff) {
1063                         u8 *opt = ext++;
1064                         if (*opt == 0)  /* Padding */
1065                                 continue;
1066                         ext += *ext + 1;
1067                         if (ext < end)
1068                                 ic_do_bootp_ext(opt);
1069                 }
1070         }
1071
1072         /* We have a winner! */
1073         ic_dev = dev;
1074         ic_myaddr = b->your_ip;
1075         ic_servaddr = b->server_ip;
1076         if (ic_gateway == NONE && b->relay_ip)
1077                 ic_gateway = b->relay_ip;
1078         if (ic_nameservers[0] == NONE)
1079                 ic_nameservers[0] = ic_servaddr;
1080         ic_got_reply = IC_BOOTP;
1081
1082 drop_unlock:
1083         /* Show's over.  Nothing to see here.  */
1084         spin_unlock(&ic_recv_lock);
1085
1086 drop:
1087         /* Throw the packet out. */
1088         kfree_skb(skb);
1089
1090         return 0;
1091 }
1092
1093
1094 #endif
1095
1096
1097 /*
1098  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1099  */
1100
1101 #ifdef IPCONFIG_DYNAMIC
1102
1103 static int __init ic_dynamic(void)
1104 {
1105         int retries;
1106         struct ic_device *d;
1107         unsigned long start_jiffies, timeout, jiff;
1108         int do_bootp = ic_proto_have_if & IC_BOOTP;
1109         int do_rarp = ic_proto_have_if & IC_RARP;
1110
1111         /*
1112          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1113          * This routine gets only called when some pieces of information
1114          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1115          */
1116         if (!ic_proto_enabled) {
1117                 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1118                 return -1;
1119         }
1120
1121 #ifdef IPCONFIG_BOOTP
1122         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1123                 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1124 #endif
1125 #ifdef IPCONFIG_RARP
1126         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1127                 printk(KERN_ERR "RARP: No suitable device found.\n");
1128 #endif
1129
1130         if (!ic_proto_have_if)
1131                 /* Error message already printed */
1132                 return -1;
1133
1134         /*
1135          * Setup protocols
1136          */
1137 #ifdef IPCONFIG_BOOTP
1138         if (do_bootp)
1139                 ic_bootp_init();
1140 #endif
1141 #ifdef IPCONFIG_RARP
1142         if (do_rarp)
1143                 ic_rarp_init();
1144 #endif
1145
1146         /*
1147          * Send requests and wait, until we get an answer. This loop
1148          * seems to be a terrible waste of CPU time, but actually there is
1149          * only one process running at all, so we don't need to use any
1150          * scheduler functions.
1151          * [Actually we could now, but the nothing else running note still
1152          *  applies.. - AC]
1153          */
1154         printk(KERN_NOTICE "Sending %s%s%s requests .",
1155                do_bootp
1156                 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1157                (do_bootp && do_rarp) ? " and " : "",
1158                do_rarp ? "RARP" : "");
1159
1160         start_jiffies = jiffies;
1161         d = ic_first_dev;
1162         retries = CONF_SEND_RETRIES;
1163         get_random_bytes(&timeout, sizeof(timeout));
1164         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1165         for (;;) {
1166                 /* Track the device we are configuring */
1167                 ic_dev_xid = d->xid;
1168
1169 #ifdef IPCONFIG_BOOTP
1170                 if (do_bootp && (d->able & IC_BOOTP))
1171                         ic_bootp_send_if(d, jiffies - start_jiffies);
1172 #endif
1173 #ifdef IPCONFIG_RARP
1174                 if (do_rarp && (d->able & IC_RARP))
1175                         ic_rarp_send_if(d);
1176 #endif
1177
1178                 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1179                 while (time_before(jiffies, jiff) && !ic_got_reply)
1180                         schedule_timeout_uninterruptible(1);
1181 #ifdef IPCONFIG_DHCP
1182                 /* DHCP isn't done until we get a DHCPACK. */
1183                 if ((ic_got_reply & IC_BOOTP) &&
1184                     (ic_proto_enabled & IC_USE_DHCP) &&
1185                     ic_dhcp_msgtype != DHCPACK) {
1186                         ic_got_reply = 0;
1187                         printk(",");
1188                         continue;
1189                 }
1190 #endif /* IPCONFIG_DHCP */
1191
1192                 if (ic_got_reply) {
1193                         printk(" OK\n");
1194                         break;
1195                 }
1196
1197                 if ((d = d->next))
1198                         continue;
1199
1200                 if (! --retries) {
1201                         printk(" timed out!\n");
1202                         break;
1203                 }
1204
1205                 d = ic_first_dev;
1206
1207                 timeout = timeout CONF_TIMEOUT_MULT;
1208                 if (timeout > CONF_TIMEOUT_MAX)
1209                         timeout = CONF_TIMEOUT_MAX;
1210
1211                 printk(".");
1212         }
1213
1214 #ifdef IPCONFIG_BOOTP
1215         if (do_bootp)
1216                 ic_bootp_cleanup();
1217 #endif
1218 #ifdef IPCONFIG_RARP
1219         if (do_rarp)
1220                 ic_rarp_cleanup();
1221 #endif
1222
1223         if (!ic_got_reply) {
1224                 ic_myaddr = NONE;
1225                 return -1;
1226         }
1227
1228         printk("IP-Config: Got %s answer from %pI4, ",
1229                 ((ic_got_reply & IC_RARP) ? "RARP"
1230                  : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1231                 &ic_servaddr);
1232         printk("my address is %pI4\n", &ic_myaddr);
1233
1234         return 0;
1235 }
1236
1237 #endif /* IPCONFIG_DYNAMIC */
1238
1239 #ifdef CONFIG_PROC_FS
1240
1241 static int pnp_seq_show(struct seq_file *seq, void *v)
1242 {
1243         int i;
1244
1245         if (ic_proto_used & IC_PROTO)
1246                 seq_printf(seq, "#PROTO: %s\n",
1247                            (ic_proto_used & IC_RARP) ? "RARP"
1248                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1249         else
1250                 seq_puts(seq, "#MANUAL\n");
1251
1252         if (ic_domain[0])
1253                 seq_printf(seq,
1254                            "domain %s\n", ic_domain);
1255         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1256                 if (ic_nameservers[i] != NONE)
1257                         seq_printf(seq, "nameserver %pI4\n",
1258                                    &ic_nameservers[i]);
1259         }
1260         if (ic_servaddr != NONE)
1261                 seq_printf(seq, "bootserver %pI4\n",
1262                            &ic_servaddr);
1263         return 0;
1264 }
1265
1266 static int pnp_seq_open(struct inode *indoe, struct file *file)
1267 {
1268         return single_open(file, pnp_seq_show, NULL);
1269 }
1270
1271 static const struct file_operations pnp_seq_fops = {
1272         .owner          = THIS_MODULE,
1273         .open           = pnp_seq_open,
1274         .read           = seq_read,
1275         .llseek         = seq_lseek,
1276         .release        = single_release,
1277 };
1278 #endif /* CONFIG_PROC_FS */
1279
1280 /*
1281  *  Extract IP address from the parameter string if needed. Note that we
1282  *  need to have root_server_addr set _before_ IPConfig gets called as it
1283  *  can override it.
1284  */
1285 __be32 __init root_nfs_parse_addr(char *name)
1286 {
1287         __be32 addr;
1288         int octets = 0;
1289         char *cp, *cq;
1290
1291         cp = cq = name;
1292         while (octets < 4) {
1293                 while (*cp >= '0' && *cp <= '9')
1294                         cp++;
1295                 if (cp == cq || cp - cq > 3)
1296                         break;
1297                 if (*cp == '.' || octets == 3)
1298                         octets++;
1299                 if (octets < 4)
1300                         cp++;
1301                 cq = cp;
1302         }
1303         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1304                 if (*cp == ':')
1305                         *cp++ = '\0';
1306                 addr = in_aton(name);
1307                 memmove(name, cp, strlen(cp) + 1);
1308         } else
1309                 addr = NONE;
1310
1311         return addr;
1312 }
1313
1314 #define DEVICE_WAIT_MAX         12 /* 12 seconds */
1315
1316 static int __init wait_for_devices(void)
1317 {
1318         int i;
1319
1320         msleep(CONF_PRE_OPEN);
1321         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1322                 struct net_device *dev;
1323                 int found = 0;
1324
1325                 rtnl_lock();
1326                 for_each_netdev(&init_net, dev) {
1327                         if (ic_device_match(dev)) {
1328                                 found = 1;
1329                                 break;
1330                         }
1331                 }
1332                 rtnl_unlock();
1333                 if (found)
1334                         return 0;
1335                 ssleep(1);
1336         }
1337         return -ENODEV;
1338 }
1339
1340 /*
1341  *      IP Autoconfig dispatcher.
1342  */
1343
1344 static int __init ip_auto_config(void)
1345 {
1346         __be32 addr;
1347 #ifdef IPCONFIG_DYNAMIC
1348         int retries = CONF_OPEN_RETRIES;
1349 #endif
1350         int err;
1351
1352 #ifdef CONFIG_PROC_FS
1353         proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1354 #endif /* CONFIG_PROC_FS */
1355
1356         if (!ic_enable)
1357                 return 0;
1358
1359         DBG(("IP-Config: Entered.\n"));
1360 #ifdef IPCONFIG_DYNAMIC
1361  try_try_again:
1362 #endif
1363         /* Wait for devices to appear */
1364         err = wait_for_devices();
1365         if (err)
1366                 return err;
1367
1368         /* Setup all network devices */
1369         err = ic_open_devs();
1370         if (err)
1371                 return err;
1372
1373         /* Give drivers a chance to settle */
1374         ssleep(CONF_POST_OPEN);
1375
1376         /*
1377          * If the config information is insufficient (e.g., our IP address or
1378          * IP address of the boot server is missing or we have multiple network
1379          * interfaces and no default was set), use BOOTP or RARP to get the
1380          * missing values.
1381          */
1382         if (ic_myaddr == NONE ||
1383 #ifdef CONFIG_ROOT_NFS
1384             (root_server_addr == NONE &&
1385              ic_servaddr == NONE &&
1386              ROOT_DEV == Root_NFS) ||
1387 #endif
1388             ic_first_dev->next) {
1389 #ifdef IPCONFIG_DYNAMIC
1390                 if (ic_dynamic() < 0) {
1391                         ic_close_devs();
1392
1393                         /*
1394                          * I don't know why, but sometimes the
1395                          * eepro100 driver (at least) gets upset and
1396                          * doesn't work the first time it's opened.
1397                          * But then if you close it and reopen it, it
1398                          * works just fine.  So we need to try that at
1399                          * least once before giving up.
1400                          *
1401                          * Also, if the root will be NFS-mounted, we
1402                          * have nowhere to go if DHCP fails.  So we
1403                          * just have to keep trying forever.
1404                          *
1405                          *                              -- Chip
1406                          */
1407 #ifdef CONFIG_ROOT_NFS
1408                         if (ROOT_DEV ==  Root_NFS) {
1409                                 printk(KERN_ERR
1410                                         "IP-Config: Retrying forever (NFS root)...\n");
1411                                 goto try_try_again;
1412                         }
1413 #endif
1414
1415                         if (--retries) {
1416                                 printk(KERN_ERR
1417                                        "IP-Config: Reopening network devices...\n");
1418                                 goto try_try_again;
1419                         }
1420
1421                         /* Oh, well.  At least we tried. */
1422                         printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1423                         return -1;
1424                 }
1425 #else /* !DYNAMIC */
1426                 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1427                 ic_close_devs();
1428                 return -1;
1429 #endif /* IPCONFIG_DYNAMIC */
1430         } else {
1431                 /* Device selected manually or only one device -> use it */
1432                 ic_dev = ic_first_dev->dev;
1433         }
1434
1435         addr = root_nfs_parse_addr(root_server_path);
1436         if (root_server_addr == NONE)
1437                 root_server_addr = addr;
1438
1439         /*
1440          * Use defaults whereever applicable.
1441          */
1442         if (ic_defaults() < 0)
1443                 return -1;
1444
1445         /*
1446          * Close all network devices except the device we've
1447          * autoconfigured and set up routes.
1448          */
1449         ic_close_devs();
1450         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1451                 return -1;
1452
1453         /*
1454          * Record which protocol was actually used.
1455          */
1456 #ifdef IPCONFIG_DYNAMIC
1457         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1458 #endif
1459
1460 #ifndef IPCONFIG_SILENT
1461         /*
1462          * Clue in the operator.
1463          */
1464         printk("IP-Config: Complete:");
1465         printk("\n     device=%s", ic_dev->name);
1466         printk(", addr=%pI4", &ic_myaddr);
1467         printk(", mask=%pI4", &ic_netmask);
1468         printk(", gw=%pI4", &ic_gateway);
1469         printk(",\n     host=%s, domain=%s, nis-domain=%s",
1470                utsname()->nodename, ic_domain, utsname()->domainname);
1471         printk(",\n     bootserver=%pI4", &ic_servaddr);
1472         printk(", rootserver=%pI4", &root_server_addr);
1473         printk(", rootpath=%s", root_server_path);
1474         if (ic_dev_mtu)
1475                 printk(", mtu=%d", ic_dev_mtu);
1476         printk("\n");
1477 #endif /* !SILENT */
1478
1479         return 0;
1480 }
1481
1482 late_initcall(ip_auto_config);
1483
1484
1485 /*
1486  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1487  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1488  */
1489 static int __init ic_proto_name(char *name)
1490 {
1491         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1492                 return 1;
1493         }
1494         if (!strcmp(name, "off") || !strcmp(name, "none")) {
1495                 return 0;
1496         }
1497 #ifdef CONFIG_IP_PNP_DHCP
1498         else if (!strcmp(name, "dhcp")) {
1499                 ic_proto_enabled &= ~IC_RARP;
1500                 return 1;
1501         }
1502 #endif
1503 #ifdef CONFIG_IP_PNP_BOOTP
1504         else if (!strcmp(name, "bootp")) {
1505                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1506                 return 1;
1507         }
1508 #endif
1509 #ifdef CONFIG_IP_PNP_RARP
1510         else if (!strcmp(name, "rarp")) {
1511                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1512                 return 1;
1513         }
1514 #endif
1515 #ifdef IPCONFIG_DYNAMIC
1516         else if (!strcmp(name, "both")) {
1517                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1518                 return 1;
1519         }
1520 #endif
1521         return 0;
1522 }
1523
1524 static int __init ip_auto_config_setup(char *addrs)
1525 {
1526         char *cp, *ip, *dp;
1527         int num = 0;
1528
1529         ic_set_manually = 1;
1530         ic_enable = 1;
1531
1532         /*
1533          * If any dhcp, bootp etc options are set, leave autoconfig on
1534          * and skip the below static IP processing.
1535          */
1536         if (ic_proto_name(addrs))
1537                 return 1;
1538
1539         /* If no static IP is given, turn off autoconfig and bail.  */
1540         if (*addrs == 0 ||
1541             strcmp(addrs, "off") == 0 ||
1542             strcmp(addrs, "none") == 0) {
1543                 ic_enable = 0;
1544                 return 1;
1545         }
1546
1547         /* Parse string for static IP assignment.  */
1548         ip = addrs;
1549         while (ip && *ip) {
1550                 if ((cp = strchr(ip, ':')))
1551                         *cp++ = '\0';
1552                 if (strlen(ip) > 0) {
1553                         DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1554                         switch (num) {
1555                         case 0:
1556                                 if ((ic_myaddr = in_aton(ip)) == ANY)
1557                                         ic_myaddr = NONE;
1558                                 break;
1559                         case 1:
1560                                 if ((ic_servaddr = in_aton(ip)) == ANY)
1561                                         ic_servaddr = NONE;
1562                                 break;
1563                         case 2:
1564                                 if ((ic_gateway = in_aton(ip)) == ANY)
1565                                         ic_gateway = NONE;
1566                                 break;
1567                         case 3:
1568                                 if ((ic_netmask = in_aton(ip)) == ANY)
1569                                         ic_netmask = NONE;
1570                                 break;
1571                         case 4:
1572                                 if ((dp = strchr(ip, '.'))) {
1573                                         *dp++ = '\0';
1574                                         strlcpy(utsname()->domainname, dp,
1575                                                 sizeof(utsname()->domainname));
1576                                 }
1577                                 strlcpy(utsname()->nodename, ip,
1578                                         sizeof(utsname()->nodename));
1579                                 ic_host_name_set = 1;
1580                                 break;
1581                         case 5:
1582                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1583                                 break;
1584                         case 6:
1585                                 if (ic_proto_name(ip) == 0 &&
1586                                     ic_myaddr == NONE) {
1587                                         ic_enable = 0;
1588                                 }
1589                                 break;
1590                         }
1591                 }
1592                 ip = cp;
1593                 num++;
1594         }
1595
1596         return 1;
1597 }
1598
1599 static int __init nfsaddrs_config_setup(char *addrs)
1600 {
1601         return ip_auto_config_setup(addrs);
1602 }
1603
1604 static int __init vendor_class_identifier_setup(char *addrs)
1605 {
1606         if (strlcpy(vendor_class_identifier, addrs,
1607                     sizeof(vendor_class_identifier))
1608             >= sizeof(vendor_class_identifier))
1609                 printk(KERN_WARNING "DHCP: vendorclass too long, truncated to \"%s\"",
1610                        vendor_class_identifier);
1611         return 1;
1612 }
1613
1614 __setup("ip=", ip_auto_config_setup);
1615 __setup("nfsaddrs=", nfsaddrs_config_setup);
1616 __setup("dhcpclass=", vendor_class_identifier_setup);