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