GNU Linux-libre 4.9.288-gnu1
[releases.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 <linux/export.h>
58 #include <net/net_namespace.h>
59 #include <net/arp.h>
60 #include <net/ip.h>
61 #include <net/ipconfig.h>
62 #include <net/route.h>
63
64 #include <asm/uaccess.h>
65 #include <net/checksum.h>
66 #include <asm/processor.h>
67
68 #if defined(CONFIG_IP_PNP_DHCP)
69 #define IPCONFIG_DHCP
70 #endif
71 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
72 #define IPCONFIG_BOOTP
73 #endif
74 #if defined(CONFIG_IP_PNP_RARP)
75 #define IPCONFIG_RARP
76 #endif
77 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
78 #define IPCONFIG_DYNAMIC
79 #endif
80
81 /* Define the friendly delay before and after opening net devices */
82 #define CONF_POST_OPEN          10      /* After opening: 10 msecs */
83 #define CONF_CARRIER_TIMEOUT    120000  /* Wait for carrier timeout */
84
85 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
86 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
87 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
88 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
89 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
90 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
91 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
92 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
93                                            - '3' from resolv.h */
94
95 #define NONE cpu_to_be32(INADDR_NONE)
96 #define ANY cpu_to_be32(INADDR_ANY)
97
98 /*
99  * Public IP configuration
100  */
101
102 /* This is used by platforms which might be able to set the ipconfig
103  * variables using firmware environment vars.  If this is set, it will
104  * ignore such firmware variables.
105  */
106 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
107
108 static int ic_enable __initdata;                /* IP config enabled? */
109
110 /* Protocol choice */
111 int ic_proto_enabled __initdata = 0
112 #ifdef IPCONFIG_BOOTP
113                         | IC_BOOTP
114 #endif
115 #ifdef CONFIG_IP_PNP_DHCP
116                         | IC_USE_DHCP
117 #endif
118 #ifdef IPCONFIG_RARP
119                         | IC_RARP
120 #endif
121                         ;
122
123 static int ic_host_name_set __initdata; /* Host name set by us? */
124
125 __be32 ic_myaddr = NONE;                /* My IP address */
126 static __be32 ic_netmask = NONE;        /* Netmask for local subnet */
127 __be32 ic_gateway = NONE;       /* Gateway IP address */
128
129 #ifdef IPCONFIG_DYNAMIC
130 static __be32 ic_addrservaddr = NONE;   /* IP Address of the IP addresses'server */
131 #endif
132
133 __be32 ic_servaddr = NONE;      /* Boot server IP address */
134
135 __be32 root_server_addr = NONE; /* Address of NFS server */
136 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
137
138 /* vendor class identifier */
139 static char vendor_class_identifier[253] __initdata;
140
141 #if defined(CONFIG_IP_PNP_DHCP)
142 static char dhcp_client_identifier[253] __initdata;
143 #endif
144
145 /* Persistent data: */
146
147 #ifdef IPCONFIG_DYNAMIC
148 static int ic_proto_used;                       /* Protocol used, if any */
149 #else
150 #define ic_proto_used 0
151 #endif
152 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
153 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
154
155 /*
156  * Private state.
157  */
158
159 /* Name of user-selected boot device */
160 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
161
162 /* Protocols supported by available interfaces */
163 static int ic_proto_have_if __initdata;
164
165 /* MTU for boot device */
166 static int ic_dev_mtu __initdata;
167
168 #ifdef IPCONFIG_DYNAMIC
169 static DEFINE_SPINLOCK(ic_recv_lock);
170 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
171 #endif
172 #ifdef IPCONFIG_DHCP
173 static int ic_dhcp_msgtype __initdata;  /* DHCP msg type received */
174 #endif
175
176
177 /*
178  *      Network devices
179  */
180
181 struct ic_device {
182         struct ic_device *next;
183         struct net_device *dev;
184         unsigned short flags;
185         short able;
186         __be32 xid;
187 };
188
189 static struct ic_device *ic_first_dev __initdata;       /* List of open device */
190 static struct ic_device *ic_dev __initdata;             /* Selected device */
191
192 static bool __init ic_is_init_dev(struct net_device *dev)
193 {
194         if (dev->flags & IFF_LOOPBACK)
195                 return false;
196         return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
197             (!(dev->flags & IFF_LOOPBACK) &&
198              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
199              strncmp(dev->name, "dummy", 5));
200 }
201
202 static int __init ic_open_devs(void)
203 {
204         struct ic_device *d, **last;
205         struct net_device *dev;
206         unsigned short oflags;
207         unsigned long start, next_msg;
208
209         last = &ic_first_dev;
210         rtnl_lock();
211
212         /* bring loopback and DSA master network devices up first */
213         for_each_netdev(&init_net, dev) {
214                 if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
215                         continue;
216                 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
217                         pr_err("IP-Config: Failed to open %s\n", dev->name);
218         }
219
220         for_each_netdev(&init_net, dev) {
221                 if (ic_is_init_dev(dev)) {
222                         int able = 0;
223                         if (dev->mtu >= 364)
224                                 able |= IC_BOOTP;
225                         else
226                                 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
227                                         dev->name, dev->mtu);
228                         if (!(dev->flags & IFF_NOARP))
229                                 able |= IC_RARP;
230                         able &= ic_proto_enabled;
231                         if (ic_proto_enabled && !able)
232                                 continue;
233                         oflags = dev->flags;
234                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
235                                 pr_err("IP-Config: Failed to open %s\n",
236                                        dev->name);
237                                 continue;
238                         }
239                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
240                                 rtnl_unlock();
241                                 return -ENOMEM;
242                         }
243                         d->dev = dev;
244                         *last = d;
245                         last = &d->next;
246                         d->flags = oflags;
247                         d->able = able;
248                         if (able & IC_BOOTP)
249                                 get_random_bytes(&d->xid, sizeof(__be32));
250                         else
251                                 d->xid = 0;
252                         ic_proto_have_if |= able;
253                         pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
254                                  dev->name, able, d->xid);
255                 }
256         }
257
258         /* no point in waiting if we could not bring up at least one device */
259         if (!ic_first_dev)
260                 goto have_carrier;
261
262         /* wait for a carrier on at least one device */
263         start = jiffies;
264         next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
265         while (time_before(jiffies, start +
266                            msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
267                 int wait, elapsed;
268
269                 for_each_netdev(&init_net, dev)
270                         if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
271                                 goto have_carrier;
272
273                 msleep(1);
274
275                 if (time_before(jiffies, next_msg))
276                         continue;
277
278                 elapsed = jiffies_to_msecs(jiffies - start);
279                 wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
280                 pr_info("Waiting up to %d more seconds for network.\n", wait);
281                 next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
282         }
283 have_carrier:
284         rtnl_unlock();
285
286         *last = NULL;
287
288         if (!ic_first_dev) {
289                 if (user_dev_name[0])
290                         pr_err("IP-Config: Device `%s' not found\n",
291                                user_dev_name);
292                 else
293                         pr_err("IP-Config: No network devices available\n");
294                 return -ENODEV;
295         }
296         return 0;
297 }
298
299 static void __init ic_close_devs(void)
300 {
301         struct ic_device *d, *next;
302         struct net_device *dev;
303
304         rtnl_lock();
305         next = ic_first_dev;
306         while ((d = next)) {
307                 next = d->next;
308                 dev = d->dev;
309                 if (d != ic_dev && !netdev_uses_dsa(dev)) {
310                         pr_debug("IP-Config: Downing %s\n", dev->name);
311                         dev_change_flags(dev, d->flags);
312                 }
313                 kfree(d);
314         }
315         rtnl_unlock();
316 }
317
318 /*
319  *      Interface to various network functions.
320  */
321
322 static inline void
323 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
324 {
325         sin->sin_family = AF_INET;
326         sin->sin_addr.s_addr = addr;
327         sin->sin_port = port;
328 }
329
330 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
331 {
332         int res;
333
334         mm_segment_t oldfs = get_fs();
335         set_fs(get_ds());
336         res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
337         set_fs(oldfs);
338         return res;
339 }
340
341 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
342 {
343         int res;
344
345         mm_segment_t oldfs = get_fs();
346         set_fs(get_ds());
347         res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
348         set_fs(oldfs);
349         return res;
350 }
351
352 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
353 {
354         int res;
355
356         mm_segment_t oldfs = get_fs();
357         set_fs(get_ds());
358         res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
359         set_fs(oldfs);
360         return res;
361 }
362
363 /*
364  *      Set up interface addresses and routes.
365  */
366
367 static int __init ic_setup_if(void)
368 {
369         struct ifreq ir;
370         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
371         int err;
372
373         memset(&ir, 0, sizeof(ir));
374         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
375         set_sockaddr(sin, ic_myaddr, 0);
376         if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
377                 pr_err("IP-Config: Unable to set interface address (%d)\n",
378                        err);
379                 return -1;
380         }
381         set_sockaddr(sin, ic_netmask, 0);
382         if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
383                 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
384                        err);
385                 return -1;
386         }
387         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
388         if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
389                 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
390                        err);
391                 return -1;
392         }
393         /* Handle the case where we need non-standard MTU on the boot link (a network
394          * using jumbo frames, for instance).  If we can't set the mtu, don't error
395          * out, we'll try to muddle along.
396          */
397         if (ic_dev_mtu != 0) {
398                 strcpy(ir.ifr_name, ic_dev->dev->name);
399                 ir.ifr_mtu = ic_dev_mtu;
400                 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
401                         pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
402                                ic_dev_mtu, err);
403         }
404         return 0;
405 }
406
407 static int __init ic_setup_routes(void)
408 {
409         /* No need to setup device routes, only the default route... */
410
411         if (ic_gateway != NONE) {
412                 struct rtentry rm;
413                 int err;
414
415                 memset(&rm, 0, sizeof(rm));
416                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
417                         pr_err("IP-Config: Gateway not on directly connected network\n");
418                         return -1;
419                 }
420                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
421                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
422                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
423                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
424                 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
425                         pr_err("IP-Config: Cannot add default route (%d)\n",
426                                err);
427                         return -1;
428                 }
429         }
430
431         return 0;
432 }
433
434 /*
435  *      Fill in default values for all missing parameters.
436  */
437
438 static int __init ic_defaults(void)
439 {
440         /*
441          *      At this point we have no userspace running so need not
442          *      claim locks on system_utsname
443          */
444
445         if (!ic_host_name_set)
446                 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
447
448         if (root_server_addr == NONE)
449                 root_server_addr = ic_servaddr;
450
451         if (ic_netmask == NONE) {
452                 if (IN_CLASSA(ntohl(ic_myaddr)))
453                         ic_netmask = htonl(IN_CLASSA_NET);
454                 else if (IN_CLASSB(ntohl(ic_myaddr)))
455                         ic_netmask = htonl(IN_CLASSB_NET);
456                 else if (IN_CLASSC(ntohl(ic_myaddr)))
457                         ic_netmask = htonl(IN_CLASSC_NET);
458                 else {
459                         pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
460                                &ic_myaddr);
461                         return -1;
462                 }
463                 pr_notice("IP-Config: Guessing netmask %pI4\n",
464                           &ic_netmask);
465         }
466
467         return 0;
468 }
469
470 /*
471  *      RARP support.
472  */
473
474 #ifdef IPCONFIG_RARP
475
476 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
477
478 static struct packet_type rarp_packet_type __initdata = {
479         .type = cpu_to_be16(ETH_P_RARP),
480         .func = ic_rarp_recv,
481 };
482
483 static inline void __init ic_rarp_init(void)
484 {
485         dev_add_pack(&rarp_packet_type);
486 }
487
488 static inline void __init ic_rarp_cleanup(void)
489 {
490         dev_remove_pack(&rarp_packet_type);
491 }
492
493 /*
494  *  Process received RARP packet.
495  */
496 static int __init
497 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
498 {
499         struct arphdr *rarp;
500         unsigned char *rarp_ptr;
501         __be32 sip, tip;
502         unsigned char *tha;             /* t for "target" */
503         struct ic_device *d;
504
505         if (!net_eq(dev_net(dev), &init_net))
506                 goto drop;
507
508         skb = skb_share_check(skb, GFP_ATOMIC);
509         if (!skb)
510                 return NET_RX_DROP;
511
512         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
513                 goto drop;
514
515         /* Basic sanity checks can be done without the lock.  */
516         rarp = (struct arphdr *)skb_transport_header(skb);
517
518         /* If this test doesn't pass, it's not IP, or we should
519          * ignore it anyway.
520          */
521         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
522                 goto drop;
523
524         /* If it's not a RARP reply, delete it. */
525         if (rarp->ar_op != htons(ARPOP_RREPLY))
526                 goto drop;
527
528         /* If it's not Ethernet, delete it. */
529         if (rarp->ar_pro != htons(ETH_P_IP))
530                 goto drop;
531
532         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
533                 goto drop;
534
535         /* OK, it is all there and looks valid, process... */
536         rarp = (struct arphdr *)skb_transport_header(skb);
537         rarp_ptr = (unsigned char *) (rarp + 1);
538
539         /* One reply at a time, please. */
540         spin_lock(&ic_recv_lock);
541
542         /* If we already have a reply, just drop the packet */
543         if (ic_got_reply)
544                 goto drop_unlock;
545
546         /* Find the ic_device that the packet arrived on */
547         d = ic_first_dev;
548         while (d && d->dev != dev)
549                 d = d->next;
550         if (!d)
551                 goto drop_unlock;       /* should never happen */
552
553         /* Extract variable-width fields */
554         rarp_ptr += dev->addr_len;
555         memcpy(&sip, rarp_ptr, 4);
556         rarp_ptr += 4;
557         tha = rarp_ptr;
558         rarp_ptr += dev->addr_len;
559         memcpy(&tip, rarp_ptr, 4);
560
561         /* Discard packets which are not meant for us. */
562         if (memcmp(tha, dev->dev_addr, dev->addr_len))
563                 goto drop_unlock;
564
565         /* Discard packets which are not from specified server. */
566         if (ic_servaddr != NONE && ic_servaddr != sip)
567                 goto drop_unlock;
568
569         /* We have a winner! */
570         ic_dev = d;
571         if (ic_myaddr == NONE)
572                 ic_myaddr = tip;
573         ic_servaddr = sip;
574         ic_addrservaddr = sip;
575         ic_got_reply = IC_RARP;
576
577 drop_unlock:
578         /* Show's over.  Nothing to see here.  */
579         spin_unlock(&ic_recv_lock);
580
581 drop:
582         /* Throw the packet out. */
583         kfree_skb(skb);
584         return 0;
585 }
586
587
588 /*
589  *  Send RARP request packet over a single interface.
590  */
591 static void __init ic_rarp_send_if(struct ic_device *d)
592 {
593         struct net_device *dev = d->dev;
594         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
595                  dev->dev_addr, dev->dev_addr);
596 }
597 #endif
598
599 /*
600  *  Predefine Nameservers
601  */
602 static inline void __init ic_nameservers_predef(void)
603 {
604         int i;
605
606         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
607                 ic_nameservers[i] = NONE;
608 }
609
610 /*
611  *      DHCP/BOOTP support.
612  */
613
614 #ifdef IPCONFIG_BOOTP
615
616 struct bootp_pkt {              /* BOOTP packet format */
617         struct iphdr iph;       /* IP header */
618         struct udphdr udph;     /* UDP header */
619         u8 op;                  /* 1=request, 2=reply */
620         u8 htype;               /* HW address type */
621         u8 hlen;                /* HW address length */
622         u8 hops;                /* Used only by gateways */
623         __be32 xid;             /* Transaction ID */
624         __be16 secs;            /* Seconds since we started */
625         __be16 flags;           /* Just what it says */
626         __be32 client_ip;               /* Client's IP address if known */
627         __be32 your_ip;         /* Assigned IP address */
628         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
629         __be32 relay_ip;                /* IP address of BOOTP relay */
630         u8 hw_addr[16];         /* Client's HW address */
631         u8 serv_name[64];       /* Server host name */
632         u8 boot_file[128];      /* Name of boot file */
633         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
634 };
635
636 /* packet ops */
637 #define BOOTP_REQUEST   1
638 #define BOOTP_REPLY     2
639
640 /* DHCP message types */
641 #define DHCPDISCOVER    1
642 #define DHCPOFFER       2
643 #define DHCPREQUEST     3
644 #define DHCPDECLINE     4
645 #define DHCPACK         5
646 #define DHCPNAK         6
647 #define DHCPRELEASE     7
648 #define DHCPINFORM      8
649
650 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
651
652 static struct packet_type bootp_packet_type __initdata = {
653         .type = cpu_to_be16(ETH_P_IP),
654         .func = ic_bootp_recv,
655 };
656
657 /*
658  *  Initialize DHCP/BOOTP extension fields in the request.
659  */
660
661 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
662
663 #ifdef IPCONFIG_DHCP
664
665 static void __init
666 ic_dhcp_init_options(u8 *options, struct ic_device *d)
667 {
668         u8 mt = ((ic_servaddr == NONE)
669                  ? DHCPDISCOVER : DHCPREQUEST);
670         u8 *e = options;
671         int len;
672
673         pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
674
675         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
676         e += 4;
677
678         *e++ = 53;              /* DHCP message type */
679         *e++ = 1;
680         *e++ = mt;
681
682         if (mt == DHCPREQUEST) {
683                 *e++ = 54;      /* Server ID (IP address) */
684                 *e++ = 4;
685                 memcpy(e, &ic_servaddr, 4);
686                 e += 4;
687
688                 *e++ = 50;      /* Requested IP address */
689                 *e++ = 4;
690                 memcpy(e, &ic_myaddr, 4);
691                 e += 4;
692         }
693
694         /* always? */
695         {
696                 static const u8 ic_req_params[] = {
697                         1,      /* Subnet mask */
698                         3,      /* Default gateway */
699                         6,      /* DNS server */
700                         12,     /* Host name */
701                         15,     /* Domain name */
702                         17,     /* Boot path */
703                         26,     /* MTU */
704                         40,     /* NIS domain name */
705                 };
706
707                 *e++ = 55;      /* Parameter request list */
708                 *e++ = sizeof(ic_req_params);
709                 memcpy(e, ic_req_params, sizeof(ic_req_params));
710                 e += sizeof(ic_req_params);
711
712                 if (ic_host_name_set) {
713                         *e++ = 12;      /* host-name */
714                         len = strlen(utsname()->nodename);
715                         *e++ = len;
716                         memcpy(e, utsname()->nodename, len);
717                         e += len;
718                 }
719                 if (*vendor_class_identifier) {
720                         pr_info("DHCP: sending class identifier \"%s\"\n",
721                                 vendor_class_identifier);
722                         *e++ = 60;      /* Class-identifier */
723                         len = strlen(vendor_class_identifier);
724                         *e++ = len;
725                         memcpy(e, vendor_class_identifier, len);
726                         e += len;
727                 }
728                 len = strlen(dhcp_client_identifier + 1);
729                 /* the minimum length of identifier is 2, include 1 byte type,
730                  * and can not be larger than the length of options
731                  */
732                 if (len >= 1 && len < 312 - (e - options) - 1) {
733                         *e++ = 61;
734                         *e++ = len + 1;
735                         memcpy(e, dhcp_client_identifier, len + 1);
736                         e += len + 1;
737                 }
738         }
739
740         *e++ = 255;     /* End of the list */
741 }
742
743 #endif /* IPCONFIG_DHCP */
744
745 static void __init ic_bootp_init_ext(u8 *e)
746 {
747         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
748         e += 4;
749         *e++ = 1;               /* Subnet mask request */
750         *e++ = 4;
751         e += 4;
752         *e++ = 3;               /* Default gateway request */
753         *e++ = 4;
754         e += 4;
755         *e++ = 5;               /* Name server request */
756         *e++ = 8;
757         e += 8;
758         *e++ = 12;              /* Host name request */
759         *e++ = 32;
760         e += 32;
761         *e++ = 40;              /* NIS Domain name request */
762         *e++ = 32;
763         e += 32;
764         *e++ = 17;              /* Boot path */
765         *e++ = 40;
766         e += 40;
767
768         *e++ = 57;              /* set extension buffer size for reply */
769         *e++ = 2;
770         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
771         *e++ = 150;
772
773         *e++ = 255;             /* End of the list */
774 }
775
776
777 /*
778  *  Initialize the DHCP/BOOTP mechanism.
779  */
780 static inline void __init ic_bootp_init(void)
781 {
782         /* Re-initialise all name servers to NONE, in case any were set via the
783          * "ip=" or "nfsaddrs=" kernel command line parameters: any IP addresses
784          * specified there will already have been decoded but are no longer
785          * needed
786          */
787         ic_nameservers_predef();
788
789         dev_add_pack(&bootp_packet_type);
790 }
791
792
793 /*
794  *  DHCP/BOOTP cleanup.
795  */
796 static inline void __init ic_bootp_cleanup(void)
797 {
798         dev_remove_pack(&bootp_packet_type);
799 }
800
801
802 /*
803  *  Send DHCP/BOOTP request to single interface.
804  */
805 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
806 {
807         struct net_device *dev = d->dev;
808         struct sk_buff *skb;
809         struct bootp_pkt *b;
810         struct iphdr *h;
811         int hlen = LL_RESERVED_SPACE(dev);
812         int tlen = dev->needed_tailroom;
813
814         /* Allocate packet */
815         skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
816                         GFP_KERNEL);
817         if (!skb)
818                 return;
819         skb_reserve(skb, hlen);
820         b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
821         memset(b, 0, sizeof(struct bootp_pkt));
822
823         /* Construct IP header */
824         skb_reset_network_header(skb);
825         h = ip_hdr(skb);
826         h->version = 4;
827         h->ihl = 5;
828         h->tot_len = htons(sizeof(struct bootp_pkt));
829         h->frag_off = htons(IP_DF);
830         h->ttl = 64;
831         h->protocol = IPPROTO_UDP;
832         h->daddr = htonl(INADDR_BROADCAST);
833         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
834
835         /* Construct UDP header */
836         b->udph.source = htons(68);
837         b->udph.dest = htons(67);
838         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
839         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
840
841         /* Construct DHCP/BOOTP header */
842         b->op = BOOTP_REQUEST;
843         if (dev->type < 256) /* check for false types */
844                 b->htype = dev->type;
845         else if (dev->type == ARPHRD_FDDI)
846                 b->htype = ARPHRD_ETHER;
847         else {
848                 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
849                         dev->name);
850                 b->htype = dev->type; /* can cause undefined behavior */
851         }
852
853         /* server_ip and your_ip address are both already zero per RFC2131 */
854         b->hlen = dev->addr_len;
855         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
856         b->secs = htons(jiffies_diff / HZ);
857         b->xid = d->xid;
858
859         /* add DHCP options or BOOTP extensions */
860 #ifdef IPCONFIG_DHCP
861         if (ic_proto_enabled & IC_USE_DHCP)
862                 ic_dhcp_init_options(b->exten, d);
863         else
864 #endif
865                 ic_bootp_init_ext(b->exten);
866
867         /* Chain packet down the line... */
868         skb->dev = dev;
869         skb->protocol = htons(ETH_P_IP);
870         if (dev_hard_header(skb, dev, ntohs(skb->protocol),
871                             dev->broadcast, dev->dev_addr, skb->len) < 0) {
872                 kfree_skb(skb);
873                 printk("E");
874                 return;
875         }
876
877         if (dev_queue_xmit(skb) < 0)
878                 printk("E");
879 }
880
881
882 /*
883  *  Copy BOOTP-supplied string
884  */
885 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
886 {
887         if (!len)
888                 return 0;
889         if (len > max-1)
890                 len = max-1;
891         memcpy(dest, src, len);
892         dest[len] = '\0';
893         return 1;
894 }
895
896
897 /*
898  *  Process BOOTP extensions.
899  */
900 static void __init ic_do_bootp_ext(u8 *ext)
901 {
902         u8 servers;
903         int i;
904         __be16 mtu;
905
906         u8 *c;
907
908         pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
909         for (c=ext+2; c<ext+2+ext[1]; c++)
910                 pr_debug(" %02x", *c);
911         pr_debug("\n");
912
913         switch (*ext++) {
914         case 1:         /* Subnet mask */
915                 if (ic_netmask == NONE)
916                         memcpy(&ic_netmask, ext+1, 4);
917                 break;
918         case 3:         /* Default gateway */
919                 if (ic_gateway == NONE)
920                         memcpy(&ic_gateway, ext+1, 4);
921                 break;
922         case 6:         /* DNS server */
923                 servers= *ext/4;
924                 if (servers > CONF_NAMESERVERS_MAX)
925                         servers = CONF_NAMESERVERS_MAX;
926                 for (i = 0; i < servers; i++) {
927                         if (ic_nameservers[i] == NONE)
928                                 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
929                 }
930                 break;
931         case 12:        /* Host name */
932                 if (!ic_host_name_set) {
933                         ic_bootp_string(utsname()->nodename, ext+1, *ext,
934                                         __NEW_UTS_LEN);
935                         ic_host_name_set = 1;
936                 }
937                 break;
938         case 15:        /* Domain name (DNS) */
939                 if (!ic_domain[0])
940                         ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
941                 break;
942         case 17:        /* Root path */
943                 if (!root_server_path[0])
944                         ic_bootp_string(root_server_path, ext+1, *ext,
945                                         sizeof(root_server_path));
946                 break;
947         case 26:        /* Interface MTU */
948                 memcpy(&mtu, ext+1, sizeof(mtu));
949                 ic_dev_mtu = ntohs(mtu);
950                 break;
951         case 40:        /* NIS Domain name (_not_ DNS) */
952                 ic_bootp_string(utsname()->domainname, ext+1, *ext,
953                                 __NEW_UTS_LEN);
954                 break;
955         }
956 }
957
958
959 /*
960  *  Receive BOOTP reply.
961  */
962 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
963 {
964         struct bootp_pkt *b;
965         struct iphdr *h;
966         struct ic_device *d;
967         int len, ext_len;
968
969         if (!net_eq(dev_net(dev), &init_net))
970                 goto drop;
971
972         /* Perform verifications before taking the lock.  */
973         if (skb->pkt_type == PACKET_OTHERHOST)
974                 goto drop;
975
976         skb = skb_share_check(skb, GFP_ATOMIC);
977         if (!skb)
978                 return NET_RX_DROP;
979
980         if (!pskb_may_pull(skb,
981                            sizeof(struct iphdr) +
982                            sizeof(struct udphdr)))
983                 goto drop;
984
985         b = (struct bootp_pkt *)skb_network_header(skb);
986         h = &b->iph;
987
988         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
989                 goto drop;
990
991         /* Fragments are not supported */
992         if (ip_is_fragment(h)) {
993                 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
994                 goto drop;
995         }
996
997         if (skb->len < ntohs(h->tot_len))
998                 goto drop;
999
1000         if (ip_fast_csum((char *) h, h->ihl))
1001                 goto drop;
1002
1003         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
1004                 goto drop;
1005
1006         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1007                 goto drop;
1008
1009         len = ntohs(b->udph.len) - sizeof(struct udphdr);
1010         ext_len = len - (sizeof(*b) -
1011                          sizeof(struct iphdr) -
1012                          sizeof(struct udphdr) -
1013                          sizeof(b->exten));
1014         if (ext_len < 0)
1015                 goto drop;
1016
1017         /* Ok the front looks good, make sure we can get at the rest.  */
1018         if (!pskb_may_pull(skb, skb->len))
1019                 goto drop;
1020
1021         b = (struct bootp_pkt *)skb_network_header(skb);
1022         h = &b->iph;
1023
1024         /* One reply at a time, please. */
1025         spin_lock(&ic_recv_lock);
1026
1027         /* If we already have a reply, just drop the packet */
1028         if (ic_got_reply)
1029                 goto drop_unlock;
1030
1031         /* Find the ic_device that the packet arrived on */
1032         d = ic_first_dev;
1033         while (d && d->dev != dev)
1034                 d = d->next;
1035         if (!d)
1036                 goto drop_unlock;  /* should never happen */
1037
1038         /* Is it a reply to our BOOTP request? */
1039         if (b->op != BOOTP_REPLY ||
1040             b->xid != d->xid) {
1041                 net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1042                                     d->dev->name, b->op, b->xid);
1043                 goto drop_unlock;
1044         }
1045
1046         /* Parse extensions */
1047         if (ext_len >= 4 &&
1048             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1049                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1050                 u8 *ext;
1051
1052 #ifdef IPCONFIG_DHCP
1053                 if (ic_proto_enabled & IC_USE_DHCP) {
1054                         __be32 server_id = NONE;
1055                         int mt = 0;
1056
1057                         ext = &b->exten[4];
1058                         while (ext < end && *ext != 0xff) {
1059                                 u8 *opt = ext++;
1060                                 if (*opt == 0)  /* Padding */
1061                                         continue;
1062                                 ext += *ext + 1;
1063                                 if (ext >= end)
1064                                         break;
1065                                 switch (*opt) {
1066                                 case 53:        /* Message type */
1067                                         if (opt[1])
1068                                                 mt = opt[2];
1069                                         break;
1070                                 case 54:        /* Server ID (IP address) */
1071                                         if (opt[1] >= 4)
1072                                                 memcpy(&server_id, opt + 2, 4);
1073                                         break;
1074                                 }
1075                         }
1076
1077                         pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
1078
1079                         switch (mt) {
1080                         case DHCPOFFER:
1081                                 /* While in the process of accepting one offer,
1082                                  * ignore all others.
1083                                  */
1084                                 if (ic_myaddr != NONE)
1085                                         goto drop_unlock;
1086
1087                                 /* Let's accept that offer. */
1088                                 ic_myaddr = b->your_ip;
1089                                 ic_servaddr = server_id;
1090                                 pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1091                                          &ic_myaddr, &b->iph.saddr);
1092                                 /* The DHCP indicated server address takes
1093                                  * precedence over the bootp header one if
1094                                  * they are different.
1095                                  */
1096                                 if ((server_id != NONE) &&
1097                                     (b->server_ip != server_id))
1098                                         b->server_ip = ic_servaddr;
1099                                 break;
1100
1101                         case DHCPACK:
1102                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1103                                         goto drop_unlock;
1104
1105                                 /* Yeah! */
1106                                 break;
1107
1108                         default:
1109                                 /* Urque.  Forget it*/
1110                                 ic_myaddr = NONE;
1111                                 ic_servaddr = NONE;
1112                                 goto drop_unlock;
1113                         }
1114
1115                         ic_dhcp_msgtype = mt;
1116
1117                 }
1118 #endif /* IPCONFIG_DHCP */
1119
1120                 ext = &b->exten[4];
1121                 while (ext < end && *ext != 0xff) {
1122                         u8 *opt = ext++;
1123                         if (*opt == 0)  /* Padding */
1124                                 continue;
1125                         ext += *ext + 1;
1126                         if (ext < end)
1127                                 ic_do_bootp_ext(opt);
1128                 }
1129         }
1130
1131         /* We have a winner! */
1132         ic_dev = d;
1133         ic_myaddr = b->your_ip;
1134         ic_servaddr = b->server_ip;
1135         ic_addrservaddr = b->iph.saddr;
1136         if (ic_gateway == NONE && b->relay_ip)
1137                 ic_gateway = b->relay_ip;
1138         if (ic_nameservers[0] == NONE)
1139                 ic_nameservers[0] = ic_servaddr;
1140         ic_got_reply = IC_BOOTP;
1141
1142 drop_unlock:
1143         /* Show's over.  Nothing to see here.  */
1144         spin_unlock(&ic_recv_lock);
1145
1146 drop:
1147         /* Throw the packet out. */
1148         kfree_skb(skb);
1149
1150         return 0;
1151 }
1152
1153
1154 #endif
1155
1156
1157 /*
1158  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1159  */
1160
1161 #ifdef IPCONFIG_DYNAMIC
1162
1163 static int __init ic_dynamic(void)
1164 {
1165         int retries;
1166         struct ic_device *d;
1167         unsigned long start_jiffies, timeout, jiff;
1168         int do_bootp = ic_proto_have_if & IC_BOOTP;
1169         int do_rarp = ic_proto_have_if & IC_RARP;
1170
1171         /*
1172          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1173          * This routine gets only called when some pieces of information
1174          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1175          */
1176         if (!ic_proto_enabled) {
1177                 pr_err("IP-Config: Incomplete network configuration information\n");
1178                 return -1;
1179         }
1180
1181 #ifdef IPCONFIG_BOOTP
1182         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1183                 pr_err("DHCP/BOOTP: No suitable device found\n");
1184 #endif
1185 #ifdef IPCONFIG_RARP
1186         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1187                 pr_err("RARP: No suitable device found\n");
1188 #endif
1189
1190         if (!ic_proto_have_if)
1191                 /* Error message already printed */
1192                 return -1;
1193
1194         /*
1195          * Setup protocols
1196          */
1197 #ifdef IPCONFIG_BOOTP
1198         if (do_bootp)
1199                 ic_bootp_init();
1200 #endif
1201 #ifdef IPCONFIG_RARP
1202         if (do_rarp)
1203                 ic_rarp_init();
1204 #endif
1205
1206         /*
1207          * Send requests and wait, until we get an answer. This loop
1208          * seems to be a terrible waste of CPU time, but actually there is
1209          * only one process running at all, so we don't need to use any
1210          * scheduler functions.
1211          * [Actually we could now, but the nothing else running note still
1212          *  applies.. - AC]
1213          */
1214         pr_notice("Sending %s%s%s requests .",
1215                   do_bootp
1216                   ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1217                   (do_bootp && do_rarp) ? " and " : "",
1218                   do_rarp ? "RARP" : "");
1219
1220         start_jiffies = jiffies;
1221         d = ic_first_dev;
1222         retries = CONF_SEND_RETRIES;
1223         get_random_bytes(&timeout, sizeof(timeout));
1224         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1225         for (;;) {
1226 #ifdef IPCONFIG_BOOTP
1227                 if (do_bootp && (d->able & IC_BOOTP))
1228                         ic_bootp_send_if(d, jiffies - start_jiffies);
1229 #endif
1230 #ifdef IPCONFIG_RARP
1231                 if (do_rarp && (d->able & IC_RARP))
1232                         ic_rarp_send_if(d);
1233 #endif
1234
1235                 if (!d->next) {
1236                         jiff = jiffies + timeout;
1237                         while (time_before(jiffies, jiff) && !ic_got_reply)
1238                                 schedule_timeout_uninterruptible(1);
1239                 }
1240 #ifdef IPCONFIG_DHCP
1241                 /* DHCP isn't done until we get a DHCPACK. */
1242                 if ((ic_got_reply & IC_BOOTP) &&
1243                     (ic_proto_enabled & IC_USE_DHCP) &&
1244                     ic_dhcp_msgtype != DHCPACK) {
1245                         ic_got_reply = 0;
1246                         /* continue on device that got the reply */
1247                         d = ic_dev;
1248                         pr_cont(",");
1249                         continue;
1250                 }
1251 #endif /* IPCONFIG_DHCP */
1252
1253                 if (ic_got_reply) {
1254                         pr_cont(" OK\n");
1255                         break;
1256                 }
1257
1258                 if ((d = d->next))
1259                         continue;
1260
1261                 if (! --retries) {
1262                         pr_cont(" timed out!\n");
1263                         break;
1264                 }
1265
1266                 d = ic_first_dev;
1267
1268                 timeout = timeout CONF_TIMEOUT_MULT;
1269                 if (timeout > CONF_TIMEOUT_MAX)
1270                         timeout = CONF_TIMEOUT_MAX;
1271
1272                 pr_cont(".");
1273         }
1274
1275 #ifdef IPCONFIG_BOOTP
1276         if (do_bootp)
1277                 ic_bootp_cleanup();
1278 #endif
1279 #ifdef IPCONFIG_RARP
1280         if (do_rarp)
1281                 ic_rarp_cleanup();
1282 #endif
1283
1284         if (!ic_got_reply) {
1285                 ic_myaddr = NONE;
1286                 return -1;
1287         }
1288
1289         pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1290                 ((ic_got_reply & IC_RARP) ? "RARP"
1291                 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1292                 &ic_addrservaddr, &ic_myaddr);
1293
1294         return 0;
1295 }
1296
1297 #endif /* IPCONFIG_DYNAMIC */
1298
1299 #ifdef CONFIG_PROC_FS
1300
1301 static int pnp_seq_show(struct seq_file *seq, void *v)
1302 {
1303         int i;
1304
1305         if (ic_proto_used & IC_PROTO)
1306                 seq_printf(seq, "#PROTO: %s\n",
1307                            (ic_proto_used & IC_RARP) ? "RARP"
1308                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1309         else
1310                 seq_puts(seq, "#MANUAL\n");
1311
1312         if (ic_domain[0])
1313                 seq_printf(seq,
1314                            "domain %s\n", ic_domain);
1315         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1316                 if (ic_nameservers[i] != NONE)
1317                         seq_printf(seq, "nameserver %pI4\n",
1318                                    &ic_nameservers[i]);
1319         }
1320         if (ic_servaddr != NONE)
1321                 seq_printf(seq, "bootserver %pI4\n",
1322                            &ic_servaddr);
1323         return 0;
1324 }
1325
1326 static int pnp_seq_open(struct inode *indoe, struct file *file)
1327 {
1328         return single_open(file, pnp_seq_show, NULL);
1329 }
1330
1331 static const struct file_operations pnp_seq_fops = {
1332         .owner          = THIS_MODULE,
1333         .open           = pnp_seq_open,
1334         .read           = seq_read,
1335         .llseek         = seq_lseek,
1336         .release        = single_release,
1337 };
1338 #endif /* CONFIG_PROC_FS */
1339
1340 /*
1341  *  Extract IP address from the parameter string if needed. Note that we
1342  *  need to have root_server_addr set _before_ IPConfig gets called as it
1343  *  can override it.
1344  */
1345 __be32 __init root_nfs_parse_addr(char *name)
1346 {
1347         __be32 addr;
1348         int octets = 0;
1349         char *cp, *cq;
1350
1351         cp = cq = name;
1352         while (octets < 4) {
1353                 while (*cp >= '0' && *cp <= '9')
1354                         cp++;
1355                 if (cp == cq || cp - cq > 3)
1356                         break;
1357                 if (*cp == '.' || octets == 3)
1358                         octets++;
1359                 if (octets < 4)
1360                         cp++;
1361                 cq = cp;
1362         }
1363         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1364                 if (*cp == ':')
1365                         *cp++ = '\0';
1366                 addr = in_aton(name);
1367                 memmove(name, cp, strlen(cp) + 1);
1368         } else
1369                 addr = NONE;
1370
1371         return addr;
1372 }
1373
1374 #define DEVICE_WAIT_MAX         12 /* 12 seconds */
1375
1376 static int __init wait_for_devices(void)
1377 {
1378         int i;
1379
1380         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1381                 struct net_device *dev;
1382                 int found = 0;
1383
1384                 rtnl_lock();
1385                 for_each_netdev(&init_net, dev) {
1386                         if (ic_is_init_dev(dev)) {
1387                                 found = 1;
1388                                 break;
1389                         }
1390                 }
1391                 rtnl_unlock();
1392                 if (found)
1393                         return 0;
1394                 ssleep(1);
1395         }
1396         return -ENODEV;
1397 }
1398
1399 /*
1400  *      IP Autoconfig dispatcher.
1401  */
1402
1403 static int __init ip_auto_config(void)
1404 {
1405         __be32 addr;
1406 #ifdef IPCONFIG_DYNAMIC
1407         int retries = CONF_OPEN_RETRIES;
1408 #endif
1409         int err;
1410         unsigned int i;
1411
1412         /* Initialise all name servers to NONE (but only if the "ip=" or
1413          * "nfsaddrs=" kernel command line parameters weren't decoded, otherwise
1414          * we'll overwrite the IP addresses specified there)
1415          */
1416         if (ic_set_manually == 0)
1417                 ic_nameservers_predef();
1418
1419 #ifdef CONFIG_PROC_FS
1420         proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1421 #endif /* CONFIG_PROC_FS */
1422
1423         if (!ic_enable)
1424                 return 0;
1425
1426         pr_debug("IP-Config: Entered.\n");
1427 #ifdef IPCONFIG_DYNAMIC
1428  try_try_again:
1429 #endif
1430         /* Wait for devices to appear */
1431         err = wait_for_devices();
1432         if (err)
1433                 return err;
1434
1435         /* Setup all network devices */
1436         err = ic_open_devs();
1437         if (err)
1438                 return err;
1439
1440         /* Give drivers a chance to settle */
1441         msleep(CONF_POST_OPEN);
1442
1443         /*
1444          * If the config information is insufficient (e.g., our IP address or
1445          * IP address of the boot server is missing or we have multiple network
1446          * interfaces and no default was set), use BOOTP or RARP to get the
1447          * missing values.
1448          */
1449         if (ic_myaddr == NONE ||
1450 #ifdef CONFIG_ROOT_NFS
1451             (root_server_addr == NONE &&
1452              ic_servaddr == NONE &&
1453              ROOT_DEV == Root_NFS) ||
1454 #endif
1455             ic_first_dev->next) {
1456 #ifdef IPCONFIG_DYNAMIC
1457                 if (ic_dynamic() < 0) {
1458                         ic_close_devs();
1459
1460                         /*
1461                          * I don't know why, but sometimes the
1462                          * eepro100 driver (at least) gets upset and
1463                          * doesn't work the first time it's opened.
1464                          * But then if you close it and reopen it, it
1465                          * works just fine.  So we need to try that at
1466                          * least once before giving up.
1467                          *
1468                          * Also, if the root will be NFS-mounted, we
1469                          * have nowhere to go if DHCP fails.  So we
1470                          * just have to keep trying forever.
1471                          *
1472                          *                              -- Chip
1473                          */
1474 #ifdef CONFIG_ROOT_NFS
1475                         if (ROOT_DEV ==  Root_NFS) {
1476                                 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1477                                 goto try_try_again;
1478                         }
1479 #endif
1480
1481                         if (--retries) {
1482                                 pr_err("IP-Config: Reopening network devices...\n");
1483                                 goto try_try_again;
1484                         }
1485
1486                         /* Oh, well.  At least we tried. */
1487                         pr_err("IP-Config: Auto-configuration of network failed\n");
1488                         return -1;
1489                 }
1490 #else /* !DYNAMIC */
1491                 pr_err("IP-Config: Incomplete network configuration information\n");
1492                 ic_close_devs();
1493                 return -1;
1494 #endif /* IPCONFIG_DYNAMIC */
1495         } else {
1496                 /* Device selected manually or only one device -> use it */
1497                 ic_dev = ic_first_dev;
1498         }
1499
1500         addr = root_nfs_parse_addr(root_server_path);
1501         if (root_server_addr == NONE)
1502                 root_server_addr = addr;
1503
1504         /*
1505          * Use defaults wherever applicable.
1506          */
1507         if (ic_defaults() < 0)
1508                 return -1;
1509
1510         /*
1511          * Record which protocol was actually used.
1512          */
1513 #ifdef IPCONFIG_DYNAMIC
1514         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1515 #endif
1516
1517 #ifndef IPCONFIG_SILENT
1518         /*
1519          * Clue in the operator.
1520          */
1521         pr_info("IP-Config: Complete:\n");
1522
1523         pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1524                 ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1525                 &ic_myaddr, &ic_netmask, &ic_gateway);
1526         pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1527                 utsname()->nodename, ic_domain, utsname()->domainname);
1528         pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1529                 &ic_servaddr, &root_server_addr, root_server_path);
1530         if (ic_dev_mtu)
1531                 pr_cont(", mtu=%d", ic_dev_mtu);
1532         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1533                 if (ic_nameservers[i] != NONE) {
1534                         pr_cont("     nameserver%u=%pI4",
1535                                 i, &ic_nameservers[i]);
1536                         break;
1537                 }
1538         for (i++; i < CONF_NAMESERVERS_MAX; i++)
1539                 if (ic_nameservers[i] != NONE)
1540                         pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1541         pr_cont("\n");
1542 #endif /* !SILENT */
1543
1544         /*
1545          * Close all network devices except the device we've
1546          * autoconfigured and set up routes.
1547          */
1548         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1549                 err = -1;
1550         else
1551                 err = 0;
1552
1553         ic_close_devs();
1554
1555         return err;
1556 }
1557
1558 late_initcall(ip_auto_config);
1559
1560
1561 /*
1562  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1563  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1564  */
1565 static int __init ic_proto_name(char *name)
1566 {
1567         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1568                 return 1;
1569         }
1570         if (!strcmp(name, "off") || !strcmp(name, "none")) {
1571                 return 0;
1572         }
1573 #ifdef CONFIG_IP_PNP_DHCP
1574         else if (!strncmp(name, "dhcp", 4)) {
1575                 char *client_id;
1576
1577                 ic_proto_enabled &= ~IC_RARP;
1578                 client_id = strstr(name, "dhcp,");
1579                 if (client_id) {
1580                         char *v;
1581
1582                         client_id = client_id + 5;
1583                         v = strchr(client_id, ',');
1584                         if (!v)
1585                                 return 1;
1586                         *v = 0;
1587                         if (kstrtou8(client_id, 0, dhcp_client_identifier))
1588                                 pr_debug("DHCP: Invalid client identifier type\n");
1589                         strncpy(dhcp_client_identifier + 1, v + 1, 251);
1590                         *v = ',';
1591                 }
1592                 return 1;
1593         }
1594 #endif
1595 #ifdef CONFIG_IP_PNP_BOOTP
1596         else if (!strcmp(name, "bootp")) {
1597                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1598                 return 1;
1599         }
1600 #endif
1601 #ifdef CONFIG_IP_PNP_RARP
1602         else if (!strcmp(name, "rarp")) {
1603                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1604                 return 1;
1605         }
1606 #endif
1607 #ifdef IPCONFIG_DYNAMIC
1608         else if (!strcmp(name, "both")) {
1609                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1610                 return 1;
1611         }
1612 #endif
1613         return 0;
1614 }
1615
1616 static int __init ip_auto_config_setup(char *addrs)
1617 {
1618         char *cp, *ip, *dp;
1619         int num = 0;
1620
1621         ic_set_manually = 1;
1622         ic_enable = 1;
1623
1624         /*
1625          * If any dhcp, bootp etc options are set, leave autoconfig on
1626          * and skip the below static IP processing.
1627          */
1628         if (ic_proto_name(addrs))
1629                 return 1;
1630
1631         /* If no static IP is given, turn off autoconfig and bail.  */
1632         if (*addrs == 0 ||
1633             strcmp(addrs, "off") == 0 ||
1634             strcmp(addrs, "none") == 0) {
1635                 ic_enable = 0;
1636                 return 1;
1637         }
1638
1639         /* Initialise all name servers to NONE */
1640         ic_nameservers_predef();
1641
1642         /* Parse string for static IP assignment.  */
1643         ip = addrs;
1644         while (ip && *ip) {
1645                 if ((cp = strchr(ip, ':')))
1646                         *cp++ = '\0';
1647                 if (strlen(ip) > 0) {
1648                         pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1649                         switch (num) {
1650                         case 0:
1651                                 if ((ic_myaddr = in_aton(ip)) == ANY)
1652                                         ic_myaddr = NONE;
1653                                 break;
1654                         case 1:
1655                                 if ((ic_servaddr = in_aton(ip)) == ANY)
1656                                         ic_servaddr = NONE;
1657                                 break;
1658                         case 2:
1659                                 if ((ic_gateway = in_aton(ip)) == ANY)
1660                                         ic_gateway = NONE;
1661                                 break;
1662                         case 3:
1663                                 if ((ic_netmask = in_aton(ip)) == ANY)
1664                                         ic_netmask = NONE;
1665                                 break;
1666                         case 4:
1667                                 if ((dp = strchr(ip, '.'))) {
1668                                         *dp++ = '\0';
1669                                         strlcpy(utsname()->domainname, dp,
1670                                                 sizeof(utsname()->domainname));
1671                                 }
1672                                 strlcpy(utsname()->nodename, ip,
1673                                         sizeof(utsname()->nodename));
1674                                 ic_host_name_set = 1;
1675                                 break;
1676                         case 5:
1677                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1678                                 break;
1679                         case 6:
1680                                 if (ic_proto_name(ip) == 0 &&
1681                                     ic_myaddr == NONE) {
1682                                         ic_enable = 0;
1683                                 }
1684                                 break;
1685                         case 7:
1686                                 if (CONF_NAMESERVERS_MAX >= 1) {
1687                                         ic_nameservers[0] = in_aton(ip);
1688                                         if (ic_nameservers[0] == ANY)
1689                                                 ic_nameservers[0] = NONE;
1690                                 }
1691                                 break;
1692                         case 8:
1693                                 if (CONF_NAMESERVERS_MAX >= 2) {
1694                                         ic_nameservers[1] = in_aton(ip);
1695                                         if (ic_nameservers[1] == ANY)
1696                                                 ic_nameservers[1] = NONE;
1697                                 }
1698                                 break;
1699                         }
1700                 }
1701                 ip = cp;
1702                 num++;
1703         }
1704
1705         return 1;
1706 }
1707 __setup("ip=", ip_auto_config_setup);
1708
1709 static int __init nfsaddrs_config_setup(char *addrs)
1710 {
1711         return ip_auto_config_setup(addrs);
1712 }
1713 __setup("nfsaddrs=", nfsaddrs_config_setup);
1714
1715 static int __init vendor_class_identifier_setup(char *addrs)
1716 {
1717         if (strlcpy(vendor_class_identifier, addrs,
1718                     sizeof(vendor_class_identifier))
1719             >= sizeof(vendor_class_identifier))
1720                 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1721                         vendor_class_identifier);
1722         return 1;
1723 }
1724 __setup("dhcpclass=", vendor_class_identifier_setup);