net/ipv4/ipconfig.c

   1 /*
   2  *  $Id: ipconfig.c,v 1.46 2002/02/01 22:01:04 davem Exp $
   3  *
   4  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
   5  *  user-supplied information to configure own IP address and routes.
   6  *
   7  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
   8  *
   9  *  Derived from network configuration code in fs/nfs/nfsroot.c,
  10  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
  11  *
  12  *  BOOTP rewritten to construct and analyse packets itself instead
  13  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
  14  *                                           -- MJ, December 1998
  15  *
  16  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
  17  *  initialization scheme.
  18  *      - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
  19  *
  20  *  DHCP support added.  To users this looks like a whole separate
  21  *  protocol, but we know it's just a bag on the side of BOOTP.
  22  *              -- Chip Salzenberg <chip@valinux.com>, May 2000
  23  *
  24  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
  25  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
  26  *
  27  *  Merged changes from 2.2.19 into 2.4.3
  28  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
  29  *
  30  *  Multiple Nameservers in /proc/net/pnp
  31  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
  32  */
  33
  34 #include <linux/types.h>
  35 #include <linux/string.h>
  36 #include <linux/kernel.h>
  37 #include <linux/jiffies.h>
  38 #include <linux/random.h>
  39 #include <linux/init.h>
  40 #include <linux/utsname.h>
  41 #include <linux/in.h>
  42 #include <linux/if.h>
  43 #include <linux/inet.h>
  44 #include <linux/inetdevice.h>
  45 #include <linux/netdevice.h>
  46 #include <linux/if_arp.h>
  47 #include <linux/skbuff.h>
  48 #include <linux/ip.h>
  49 #include <linux/socket.h>
  50 #include <linux/route.h>
  51 #include <linux/udp.h>
  52 #include <linux/proc_fs.h>
  53 #include <linux/seq_file.h>
  54 #include <linux/major.h>
  55 #include <linux/root_dev.h>
  56 #include <linux/delay.h>
  57 #include <linux/nfs_fs.h>
  58 #include <net/arp.h>
  59 #include <net/ip.h>
  60 #include <net/ipconfig.h>
  61 #include <net/route.h>
  62
  63 #include <asm/uaccess.h>
  64 #include <net/checksum.h>
  65 #include <asm/processor.h>
  66
  67 /* Define this to allow debugging output */
  68 #undef IPCONFIG_DEBUG
  69
  70 #ifdef IPCONFIG_DEBUG
  71 #define DBG(x) printk x
  72 #else
  73 #define DBG(x) do { } while(0)
  74 #endif
  75
  76 #if defined(CONFIG_IP_PNP_DHCP)
  77 #define IPCONFIG_DHCP
  78 #endif
  79 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
  80 #define IPCONFIG_BOOTP
  81 #endif
  82 #if defined(CONFIG_IP_PNP_RARP)
  83 #define IPCONFIG_RARP
  84 #endif
  85 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
  86 #define IPCONFIG_DYNAMIC
  87 #endif
  88
  89 /* Define the friendly delay before and after opening net devices */
  90 #define CONF_PRE_OPEN           500     /* Before opening: 1/2 second */
  91 #define CONF_POST_OPEN          1       /* After opening: 1 second */
  92
  93 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
  94 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
  95 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
  96 #define CONF_INTER_TIMEOUT      (HZ/2)  /* Inter-device timeout: 1/2 second */
  97 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
  98 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
  99 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
 100 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
 101 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
 102                                            - '3' from resolv.h */
 103
 104 #define NONE __constant_htonl(INADDR_NONE)
 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 /* Persistent data: */
 143
 144 static int ic_proto_used;                       /* Protocol used, if any */
 145 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
 146 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
 147
 148 /*
 149  * Private state.
 150  */
 151
 152 /* Name of user-selected boot device */
 153 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 154
 155 /* Protocols supported by available interfaces */
 156 static int ic_proto_have_if __initdata = 0;
 157
 158 #ifdef IPCONFIG_DYNAMIC
 159 static DEFINE_SPINLOCK(ic_recv_lock);
 160 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
 161 #endif
 162 #ifdef IPCONFIG_DHCP
 163 static int ic_dhcp_msgtype __initdata = 0;      /* DHCP msg type received */
 164 #endif
 165
 166
 167 /*
 168  *      Network devices
 169  */
 170
 171 struct ic_device {
 172         struct ic_device *next;
 173         struct net_device *dev;
 174         unsigned short flags;
 175         short able;
 176         __be32 xid;
 177 };
 178
 179 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
 180 static struct net_device *ic_dev __initdata = NULL;     /* Selected device */
 181
 182 static int __init ic_open_devs(void)
 183 {
 184         struct ic_device *d, **last;
 185         struct net_device *dev;
 186         unsigned short oflags;
 187
 188         last = &ic_first_dev;
 189         rtnl_lock();
 190
 191         /* bring loopback device up first */
 192         if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0)
 193                 printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name);
 194
 195         for (dev = dev_base; dev; dev = dev->next) {
 196                 if (dev == &loopback_dev)
 197                         continue;
 198                 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 199                     (!(dev->flags & IFF_LOOPBACK) &&
 200                      (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 201                      strncmp(dev->name, "dummy", 5))) {
 202                         int able = 0;
 203                         if (dev->mtu >= 364)
 204                                 able |= IC_BOOTP;
 205                         else
 206                                 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
 207                         if (!(dev->flags & IFF_NOARP))
 208                                 able |= IC_RARP;
 209                         able &= ic_proto_enabled;
 210                         if (ic_proto_enabled && !able)
 211                                 continue;
 212                         oflags = dev->flags;
 213                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
 214                                 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
 215                                 continue;
 216                         }
 217                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 218                                 rtnl_unlock();
 219                                 return -1;
 220                         }
 221                         d->dev = dev;
 222                         *last = d;
 223                         last = &d->next;
 224                         d->flags = oflags;
 225                         d->able = able;
 226                         if (able & IC_BOOTP)
 227                                 get_random_bytes(&d->xid, sizeof(__be32));
 228                         else
 229                                 d->xid = 0;
 230                         ic_proto_have_if |= able;
 231                         DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
 232                                 dev->name, able, d->xid));
 233                 }
 234         }
 235         rtnl_unlock();
 236
 237         *last = NULL;
 238
 239         if (!ic_first_dev) {
 240                 if (user_dev_name[0])
 241                         printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
 242                 else
 243                         printk(KERN_ERR "IP-Config: No network devices available.\n");
 244                 return -1;
 245         }
 246         return 0;
 247 }
 248
 249 static void __init ic_close_devs(void)
 250 {
 251         struct ic_device *d, *next;
 252         struct net_device *dev;
 253
 254         rtnl_lock();
 255         next = ic_first_dev;
 256         while ((d = next)) {
 257                 next = d->next;
 258                 dev = d->dev;
 259                 if (dev != ic_dev) {
 260                         DBG(("IP-Config: Downing %s\n", dev->name));
 261                         dev_change_flags(dev, d->flags);
 262                 }
 263                 kfree(d);
 264         }
 265         rtnl_unlock();
 266 }
 267
 268 /*
 269  *      Interface to various network functions.
 270  */
 271
 272 static inline void
 273 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
 274 {
 275         sin->sin_family = AF_INET;
 276         sin->sin_addr.s_addr = addr;
 277         sin->sin_port = port;
 278 }
 279
 280 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
 281 {
 282         int res;
 283
 284         mm_segment_t oldfs = get_fs();
 285         set_fs(get_ds());
 286         res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
 287         set_fs(oldfs);
 288         return res;
 289 }
 290
 291 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
 292 {
 293         int res;
 294
 295         mm_segment_t oldfs = get_fs();
 296         set_fs(get_ds());
 297         res = ip_rt_ioctl(cmd, (void __user *) arg);
 298         set_fs(oldfs);
 299         return res;
 300 }
 301
 302 /*
 303  *      Set up interface addresses and routes.
 304  */
 305
 306 static int __init ic_setup_if(void)
 307 {
 308         struct ifreq ir;
 309         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 310         int err;
 311
 312         memset(&ir, 0, sizeof(ir));
 313         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
 314         set_sockaddr(sin, ic_myaddr, 0);
 315         if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
 316                 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
 317                 return -1;
 318         }
 319         set_sockaddr(sin, ic_netmask, 0);
 320         if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
 321                 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
 322                 return -1;
 323         }
 324         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 325         if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
 326                 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
 327                 return -1;
 328         }
 329         return 0;
 330 }
 331
 332 static int __init ic_setup_routes(void)
 333 {
 334         /* No need to setup device routes, only the default route... */
 335
 336         if (ic_gateway != NONE) {
 337                 struct rtentry rm;
 338                 int err;
 339
 340                 memset(&rm, 0, sizeof(rm));
 341                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 342                         printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
 343                         return -1;
 344                 }
 345                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 346                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 347                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 348                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 349                 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
 350                         printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
 351                         return -1;
 352                 }
 353         }
 354
 355         return 0;
 356 }
 357
 358 /*
 359  *      Fill in default values for all missing parameters.
 360  */
 361
 362 static int __init ic_defaults(void)
 363 {
 364         /*
 365          *      At this point we have no userspace running so need not
 366          *      claim locks on system_utsname
 367          */
 368
 369         if (!ic_host_name_set)
 370                 sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
 371
 372         if (root_server_addr == NONE)
 373                 root_server_addr = ic_servaddr;
 374
 375         if (ic_netmask == NONE) {
 376                 if (IN_CLASSA(ntohl(ic_myaddr)))
 377                         ic_netmask = htonl(IN_CLASSA_NET);
 378                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 379                         ic_netmask = htonl(IN_CLASSB_NET);
 380                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 381                         ic_netmask = htonl(IN_CLASSC_NET);
 382                 else {
 383                         printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
 384                                 NIPQUAD(ic_myaddr));
 385                         return -1;
 386                 }
 387                 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
 388         }
 389
 390         return 0;
 391 }
 392
 393 /*
 394  *      RARP support.
 395  */
 396
 397 #ifdef IPCONFIG_RARP
 398
 399 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 400
 401 static struct packet_type rarp_packet_type __initdata = {
 402         .type = __constant_htons(ETH_P_RARP),
 403         .func = ic_rarp_recv,
 404 };
 405
 406 static inline void ic_rarp_init(void)
 407 {
 408         dev_add_pack(&rarp_packet_type);
 409 }
 410
 411 static inline void ic_rarp_cleanup(void)
 412 {
 413         dev_remove_pack(&rarp_packet_type);
 414 }
 415
 416 /*
 417  *  Process received RARP packet.
 418  */
 419 static int __init
 420 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 421 {
 422         struct arphdr *rarp;
 423         unsigned char *rarp_ptr;
 424         __be32 sip, tip;
 425         unsigned char *sha, *tha;               /* s for "source", t for "target" */
 426         struct ic_device *d;
 427
 428         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 429                 return NET_RX_DROP;
 430
 431         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 432                 goto drop;
 433
 434         /* Basic sanity checks can be done without the lock.  */
 435         rarp = (struct arphdr *)skb->h.raw;
 436
 437         /* If this test doesn't pass, it's not IP, or we should
 438          * ignore it anyway.
 439          */
 440         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 441                 goto drop;
 442
 443         /* If it's not a RARP reply, delete it. */
 444         if (rarp->ar_op != htons(ARPOP_RREPLY))
 445                 goto drop;
 446
 447         /* If it's not Ethernet, delete it. */
 448         if (rarp->ar_pro != htons(ETH_P_IP))
 449                 goto drop;
 450
 451         if (!pskb_may_pull(skb,
 452                            sizeof(struct arphdr) +
 453                            (2 * dev->addr_len) +
 454                            (2 * 4)))
 455                 goto drop;
 456
 457         /* OK, it is all there and looks valid, process... */
 458         rarp = (struct arphdr *)skb->h.raw;
 459         rarp_ptr = (unsigned char *) (rarp + 1);
 460
 461         /* One reply at a time, please. */
 462         spin_lock(&ic_recv_lock);
 463
 464         /* If we already have a reply, just drop the packet */
 465         if (ic_got_reply)
 466                 goto drop_unlock;
 467
 468         /* Find the ic_device that the packet arrived on */
 469         d = ic_first_dev;
 470         while (d && d->dev != dev)
 471                 d = d->next;
 472         if (!d)
 473                 goto drop_unlock;       /* should never happen */
 474
 475         /* Extract variable-width fields */
 476         sha = rarp_ptr;
 477         rarp_ptr += dev->addr_len;
 478         memcpy(&sip, rarp_ptr, 4);
 479         rarp_ptr += 4;
 480         tha = rarp_ptr;
 481         rarp_ptr += dev->addr_len;
 482         memcpy(&tip, rarp_ptr, 4);
 483
 484         /* Discard packets which are not meant for us. */
 485         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 486                 goto drop_unlock;
 487
 488         /* Discard packets which are not from specified server. */
 489         if (ic_servaddr != NONE && ic_servaddr != sip)
 490                 goto drop_unlock;
 491
 492         /* We have a winner! */
 493         ic_dev = dev;
 494         if (ic_myaddr == NONE)
 495                 ic_myaddr = tip;
 496         ic_servaddr = sip;
 497         ic_got_reply = IC_RARP;
 498
 499 drop_unlock:
 500         /* Show's over.  Nothing to see here.  */
 501         spin_unlock(&ic_recv_lock);
 502
 503 drop:
 504         /* Throw the packet out. */
 505         kfree_skb(skb);
 506         return 0;
 507 }
 508
 509
 510 /*
 511  *  Send RARP request packet over a single interface.
 512  */
 513 static void __init ic_rarp_send_if(struct ic_device *d)
 514 {
 515         struct net_device *dev = d->dev;
 516         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 517                  dev->dev_addr, dev->dev_addr);
 518 }
 519 #endif
 520
 521 /*
 522  *      DHCP/BOOTP support.
 523  */
 524
 525 #ifdef IPCONFIG_BOOTP
 526
 527 struct bootp_pkt {              /* BOOTP packet format */
 528         struct iphdr iph;       /* IP header */
 529         struct udphdr udph;     /* UDP header */
 530         u8 op;                  /* 1=request, 2=reply */
 531         u8 htype;               /* HW address type */
 532         u8 hlen;                /* HW address length */
 533         u8 hops;                /* Used only by gateways */
 534         __be32 xid;             /* Transaction ID */
 535         __be16 secs;            /* Seconds since we started */
 536         __be16 flags;           /* Just what it says */
 537         __be32 client_ip;               /* Client's IP address if known */
 538         __be32 your_ip;         /* Assigned IP address */
 539         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
 540         __be32 relay_ip;                /* IP address of BOOTP relay */
 541         u8 hw_addr[16];         /* Client's HW address */
 542         u8 serv_name[64];       /* Server host name */
 543         u8 boot_file[128];      /* Name of boot file */
 544         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 545 };
 546
 547 /* packet ops */
 548 #define BOOTP_REQUEST   1
 549 #define BOOTP_REPLY     2
 550
 551 /* DHCP message types */
 552 #define DHCPDISCOVER    1
 553 #define DHCPOFFER       2
 554 #define DHCPREQUEST     3
 555 #define DHCPDECLINE     4
 556 #define DHCPACK         5
 557 #define DHCPNAK         6
 558 #define DHCPRELEASE     7
 559 #define DHCPINFORM      8
 560
 561 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 562
 563 static struct packet_type bootp_packet_type __initdata = {
 564         .type = __constant_htons(ETH_P_IP),
 565         .func = ic_bootp_recv,
 566 };
 567
 568
 569 /*
 570  *  Initialize DHCP/BOOTP extension fields in the request.
 571  */
 572
 573 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 574
 575 #ifdef IPCONFIG_DHCP
 576
 577 static void __init
 578 ic_dhcp_init_options(u8 *options)
 579 {
 580         u8 mt = ((ic_servaddr == NONE)
 581                  ? DHCPDISCOVER : DHCPREQUEST);
 582         u8 *e = options;
 583
 584 #ifdef IPCONFIG_DEBUG
 585         printk("DHCP: Sending message type %d\n", mt);
 586 #endif
 587
 588         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 589         e += 4;
 590
 591         *e++ = 53;              /* DHCP message type */
 592         *e++ = 1;
 593         *e++ = mt;
 594
 595         if (mt == DHCPREQUEST) {
 596                 *e++ = 54;      /* Server ID (IP address) */
 597                 *e++ = 4;
 598                 memcpy(e, &ic_servaddr, 4);
 599                 e += 4;
 600
 601                 *e++ = 50;      /* Requested IP address */
 602                 *e++ = 4;
 603                 memcpy(e, &ic_myaddr, 4);
 604                 e += 4;
 605         }
 606
 607         /* always? */
 608         {
 609                 static const u8 ic_req_params[] = {
 610                         1,      /* Subnet mask */
 611                         3,      /* Default gateway */
 612                         6,      /* DNS server */
 613                         12,     /* Host name */
 614                         15,     /* Domain name */
 615                         17,     /* Boot path */
 616                         40,     /* NIS domain name */
 617                 };
 618
 619                 *e++ = 55;      /* Parameter request list */
 620                 *e++ = sizeof(ic_req_params);
 621                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 622                 e += sizeof(ic_req_params);
 623         }
 624
 625         *e++ = 255;     /* End of the list */
 626 }
 627
 628 #endif /* IPCONFIG_DHCP */
 629
 630 static void __init ic_bootp_init_ext(u8 *e)
 631 {
 632         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 633         e += 4;
 634         *e++ = 1;               /* Subnet mask request */
 635         *e++ = 4;
 636         e += 4;
 637         *e++ = 3;               /* Default gateway request */
 638         *e++ = 4;
 639         e += 4;
 640         *e++ = 5;               /* Name server request */
 641         *e++ = 8;
 642         e += 8;
 643         *e++ = 12;              /* Host name request */
 644         *e++ = 32;
 645         e += 32;
 646         *e++ = 40;              /* NIS Domain name request */
 647         *e++ = 32;
 648         e += 32;
 649         *e++ = 17;              /* Boot path */
 650         *e++ = 40;
 651         e += 40;
 652
 653         *e++ = 57;              /* set extension buffer size for reply */
 654         *e++ = 2;
 655         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 656         *e++ = 150;
 657
 658         *e++ = 255;             /* End of the list */
 659 }
 660
 661
 662 /*
 663  *  Initialize the DHCP/BOOTP mechanism.
 664  */
 665 static inline void ic_bootp_init(void)
 666 {
 667         int i;
 668
 669         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 670                 ic_nameservers[i] = NONE;
 671
 672         dev_add_pack(&bootp_packet_type);
 673 }
 674
 675
 676 /*
 677  *  DHCP/BOOTP cleanup.
 678  */
 679 static inline void ic_bootp_cleanup(void)
 680 {
 681         dev_remove_pack(&bootp_packet_type);
 682 }
 683
 684
 685 /*
 686  *  Send DHCP/BOOTP request to single interface.
 687  */
 688 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 689 {
 690         struct net_device *dev = d->dev;
 691         struct sk_buff *skb;
 692         struct bootp_pkt *b;
 693         int hh_len = LL_RESERVED_SPACE(dev);
 694         struct iphdr *h;
 695
 696         /* Allocate packet */
 697         skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
 698         if (!skb)
 699                 return;
 700         skb_reserve(skb, hh_len);
 701         b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
 702         memset(b, 0, sizeof(struct bootp_pkt));
 703
 704         /* Construct IP header */
 705         skb->nh.iph = h = &b->iph;
 706         h->version = 4;
 707         h->ihl = 5;
 708         h->tot_len = htons(sizeof(struct bootp_pkt));
 709         h->frag_off = htons(IP_DF);
 710         h->ttl = 64;
 711         h->protocol = IPPROTO_UDP;
 712         h->daddr = htonl(INADDR_BROADCAST);
 713         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 714
 715         /* Construct UDP header */
 716         b->udph.source = htons(68);
 717         b->udph.dest = htons(67);
 718         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 719         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 720
 721         /* Construct DHCP/BOOTP header */
 722         b->op = BOOTP_REQUEST;
 723         if (dev->type < 256) /* check for false types */
 724                 b->htype = dev->type;
 725         else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
 726                 b->htype = ARPHRD_IEEE802;
 727         else if (dev->type == ARPHRD_FDDI)
 728                 b->htype = ARPHRD_ETHER;
 729         else {
 730                 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
 731                 b->htype = dev->type; /* can cause undefined behavior */
 732         }
 733         b->hlen = dev->addr_len;
 734         b->your_ip = NONE;
 735         b->server_ip = NONE;
 736         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 737         b->secs = htons(jiffies_diff / HZ);
 738         b->xid = d->xid;
 739
 740         /* add DHCP options or BOOTP extensions */
 741 #ifdef IPCONFIG_DHCP
 742         if (ic_proto_enabled & IC_USE_DHCP)
 743                 ic_dhcp_init_options(b->exten);
 744         else
 745 #endif
 746                 ic_bootp_init_ext(b->exten);
 747
 748         /* Chain packet down the line... */
 749         skb->dev = dev;
 750         skb->protocol = htons(ETH_P_IP);
 751         if ((dev->hard_header &&
 752              dev->hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) ||
 753             dev_queue_xmit(skb) < 0)
 754                 printk("E");
 755 }
 756
 757
 758 /*
 759  *  Copy BOOTP-supplied string if not already set.
 760  */
 761 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 762 {
 763         if (!len)
 764                 return 0;
 765         if (len > max-1)
 766                 len = max-1;
 767         memcpy(dest, src, len);
 768         dest[len] = '\0';
 769         return 1;
 770 }
 771
 772
 773 /*
 774  *  Process BOOTP extensions.
 775  */
 776 static void __init ic_do_bootp_ext(u8 *ext)
 777 {
 778        u8 servers;
 779        int i;
 780
 781 #ifdef IPCONFIG_DEBUG
 782         u8 *c;
 783
 784         printk("DHCP/BOOTP: Got extension %d:",*ext);
 785         for(c=ext+2; c<ext+2+ext[1]; c++)
 786                 printk(" %02x", *c);
 787         printk("\n");
 788 #endif
 789
 790         switch (*ext++) {
 791                 case 1:         /* Subnet mask */
 792                         if (ic_netmask == NONE)
 793                                 memcpy(&ic_netmask, ext+1, 4);
 794                         break;
 795                 case 3:         /* Default gateway */
 796                         if (ic_gateway == NONE)
 797                                 memcpy(&ic_gateway, ext+1, 4);
 798                         break;
 799                 case 6:         /* DNS server */
 800                         servers= *ext/4;
 801                         if (servers > CONF_NAMESERVERS_MAX)
 802                                 servers = CONF_NAMESERVERS_MAX;
 803                         for (i = 0; i < servers; i++) {
 804                                 if (ic_nameservers[i] == NONE)
 805                                         memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 806                         }
 807                         break;
 808                 case 12:        /* Host name */
 809                         ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
 810                         ic_host_name_set = 1;
 811                         break;
 812                 case 15:        /* Domain name (DNS) */
 813                         ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
 814                         break;
 815                 case 17:        /* Root path */
 816                         if (!root_server_path[0])
 817                                 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
 818                         break;
 819                 case 40:        /* NIS Domain name (_not_ DNS) */
 820                         ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
 821                         break;
 822         }
 823 }
 824
 825
 826 /*
 827  *  Receive BOOTP reply.
 828  */
 829 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 830 {
 831         struct bootp_pkt *b;
 832         struct iphdr *h;
 833         struct ic_device *d;
 834         int len, ext_len;
 835
 836         /* Perform verifications before taking the lock.  */
 837         if (skb->pkt_type == PACKET_OTHERHOST)
 838                 goto drop;
 839
 840         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 841                 return NET_RX_DROP;
 842
 843         if (!pskb_may_pull(skb,
 844                            sizeof(struct iphdr) +
 845                            sizeof(struct udphdr)))
 846                 goto drop;
 847
 848         b = (struct bootp_pkt *) skb->nh.iph;
 849         h = &b->iph;
 850
 851         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
 852                 goto drop;
 853
 854         /* Fragments are not supported */
 855         if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
 856                 if (net_ratelimit())
 857                         printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
 858                                "reply.\n");
 859                 goto drop;
 860         }
 861
 862         if (skb->len < ntohs(h->tot_len))
 863                 goto drop;
 864
 865         if (ip_fast_csum((char *) h, h->ihl))
 866                 goto drop;
 867
 868         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
 869                 goto drop;
 870
 871         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
 872                 goto drop;
 873
 874         len = ntohs(b->udph.len) - sizeof(struct udphdr);
 875         ext_len = len - (sizeof(*b) -
 876                          sizeof(struct iphdr) -
 877                          sizeof(struct udphdr) -
 878                          sizeof(b->exten));
 879         if (ext_len < 0)
 880                 goto drop;
 881
 882         /* Ok the front looks good, make sure we can get at the rest.  */
 883         if (!pskb_may_pull(skb, skb->len))
 884                 goto drop;
 885
 886         b = (struct bootp_pkt *) skb->nh.iph;
 887         h = &b->iph;
 888
 889         /* One reply at a time, please. */
 890         spin_lock(&ic_recv_lock);
 891
 892         /* If we already have a reply, just drop the packet */
 893         if (ic_got_reply)
 894                 goto drop_unlock;
 895
 896         /* Find the ic_device that the packet arrived on */
 897         d = ic_first_dev;
 898         while (d && d->dev != dev)
 899                 d = d->next;
 900         if (!d)
 901                 goto drop_unlock;  /* should never happen */
 902
 903         /* Is it a reply to our BOOTP request? */
 904         if (b->op != BOOTP_REPLY ||
 905             b->xid != d->xid) {
 906                 if (net_ratelimit())
 907                         printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
 908                                "op[%x] xid[%x]\n",
 909                                b->op, b->xid);
 910                 goto drop_unlock;
 911         }
 912
 913         /* Parse extensions */
 914         if (ext_len >= 4 &&
 915             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
 916                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
 917                 u8 *ext;
 918
 919 #ifdef IPCONFIG_DHCP
 920                 if (ic_proto_enabled & IC_USE_DHCP) {
 921                         __be32 server_id = NONE;
 922                         int mt = 0;
 923
 924                         ext = &b->exten[4];
 925                         while (ext < end && *ext != 0xff) {
 926                                 u8 *opt = ext++;
 927                                 if (*opt == 0)  /* Padding */
 928                                         continue;
 929                                 ext += *ext + 1;
 930                                 if (ext >= end)
 931                                         break;
 932                                 switch (*opt) {
 933                                 case 53:        /* Message type */
 934                                         if (opt[1])
 935                                                 mt = opt[2];
 936                                         break;
 937                                 case 54:        /* Server ID (IP address) */
 938                                         if (opt[1] >= 4)
 939                                                 memcpy(&server_id, opt + 2, 4);
 940                                         break;
 941                                 };
 942                         }
 943
 944 #ifdef IPCONFIG_DEBUG
 945                         printk("DHCP: Got message type %d\n", mt);
 946 #endif
 947
 948                         switch (mt) {
 949                         case DHCPOFFER:
 950                                 /* While in the process of accepting one offer,
 951                                  * ignore all others.
 952                                  */
 953                                 if (ic_myaddr != NONE)
 954                                         goto drop_unlock;
 955
 956                                 /* Let's accept that offer. */
 957                                 ic_myaddr = b->your_ip;
 958                                 ic_servaddr = server_id;
 959 #ifdef IPCONFIG_DEBUG
 960                                 printk("DHCP: Offered address %u.%u.%u.%u",
 961                                        NIPQUAD(ic_myaddr));
 962                                 printk(" by server %u.%u.%u.%u\n",
 963                                        NIPQUAD(ic_servaddr));
 964 #endif
 965                                 /* The DHCP indicated server address takes
 966                                  * precedence over the bootp header one if
 967                                  * they are different.
 968                                  */
 969                                 if ((server_id != NONE) &&
 970                                     (b->server_ip != server_id))
 971                                         b->server_ip = ic_servaddr;
 972                                 break;
 973
 974                         case DHCPACK:
 975                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
 976                                         goto drop_unlock;
 977
 978                                 /* Yeah! */
 979                                 break;
 980
 981                         default:
 982                                 /* Urque.  Forget it*/
 983                                 ic_myaddr = NONE;
 984                                 ic_servaddr = NONE;
 985                                 goto drop_unlock;
 986                         };
 987
 988                         ic_dhcp_msgtype = mt;
 989
 990                 }
 991 #endif /* IPCONFIG_DHCP */
 992
 993                 ext = &b->exten[4];
 994                 while (ext < end && *ext != 0xff) {
 995                         u8 *opt = ext++;
 996                         if (*opt == 0)  /* Padding */
 997                                 continue;
 998                         ext += *ext + 1;
 999                         if (ext < end)
1000                                 ic_do_bootp_ext(opt);
1001                 }
1002         }
1003
1004         /* We have a winner! */
1005         ic_dev = dev;
1006         ic_myaddr = b->your_ip;
1007         ic_servaddr = b->server_ip;
1008         if (ic_gateway == NONE && b->relay_ip)
1009                 ic_gateway = b->relay_ip;
1010         if (ic_nameservers[0] == NONE)
1011                 ic_nameservers[0] = ic_servaddr;
1012         ic_got_reply = IC_BOOTP;
1013
1014 drop_unlock:
1015         /* Show's over.  Nothing to see here.  */
1016         spin_unlock(&ic_recv_lock);
1017
1018 drop:
1019         /* Throw the packet out. */
1020         kfree_skb(skb);
1021
1022         return 0;
1023 }
1024
1025
1026 #endif
1027
1028
1029 /*
1030  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1031  */
1032
1033 #ifdef IPCONFIG_DYNAMIC
1034
1035 static int __init ic_dynamic(void)
1036 {
1037         int retries;
1038         struct ic_device *d;
1039         unsigned long start_jiffies, timeout, jiff;
1040         int do_bootp = ic_proto_have_if & IC_BOOTP;
1041         int do_rarp = ic_proto_have_if & IC_RARP;
1042
1043         /*
1044          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1045          * This routine gets only called when some pieces of information
1046          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1047          */
1048         if (!ic_proto_enabled) {
1049                 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1050                 return -1;
1051         }
1052
1053 #ifdef IPCONFIG_BOOTP
1054         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1055                 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1056 #endif
1057 #ifdef IPCONFIG_RARP
1058         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1059                 printk(KERN_ERR "RARP: No suitable device found.\n");
1060 #endif
1061
1062         if (!ic_proto_have_if)
1063                 /* Error message already printed */
1064                 return -1;
1065
1066         /*
1067          * Setup protocols
1068          */
1069 #ifdef IPCONFIG_BOOTP
1070         if (do_bootp)
1071                 ic_bootp_init();
1072 #endif
1073 #ifdef IPCONFIG_RARP
1074         if (do_rarp)
1075                 ic_rarp_init();
1076 #endif
1077
1078         /*
1079          * Send requests and wait, until we get an answer. This loop
1080          * seems to be a terrible waste of CPU time, but actually there is
1081          * only one process running at all, so we don't need to use any
1082          * scheduler functions.
1083          * [Actually we could now, but the nothing else running note still
1084          *  applies.. - AC]
1085          */
1086         printk(KERN_NOTICE "Sending %s%s%s requests .",
1087                do_bootp
1088                 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1089                (do_bootp && do_rarp) ? " and " : "",
1090                do_rarp ? "RARP" : "");
1091
1092         start_jiffies = jiffies;
1093         d = ic_first_dev;
1094         retries = CONF_SEND_RETRIES;
1095         get_random_bytes(&timeout, sizeof(timeout));
1096         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1097         for(;;) {
1098 #ifdef IPCONFIG_BOOTP
1099                 if (do_bootp && (d->able & IC_BOOTP))
1100                         ic_bootp_send_if(d, jiffies - start_jiffies);
1101 #endif
1102 #ifdef IPCONFIG_RARP
1103                 if (do_rarp && (d->able & IC_RARP))
1104                         ic_rarp_send_if(d);
1105 #endif
1106
1107                 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1108                 while (time_before(jiffies, jiff) && !ic_got_reply)
1109                         schedule_timeout_uninterruptible(1);
1110 #ifdef IPCONFIG_DHCP
1111                 /* DHCP isn't done until we get a DHCPACK. */
1112                 if ((ic_got_reply & IC_BOOTP)
1113                     && (ic_proto_enabled & IC_USE_DHCP)
1114                     && ic_dhcp_msgtype != DHCPACK)
1115                 {
1116                         ic_got_reply = 0;
1117                         printk(",");
1118                         continue;
1119                 }
1120 #endif /* IPCONFIG_DHCP */
1121
1122                 if (ic_got_reply) {
1123                         printk(" OK\n");
1124                         break;
1125                 }
1126
1127                 if ((d = d->next))
1128                         continue;
1129
1130                 if (! --retries) {
1131                         printk(" timed out!\n");
1132                         break;
1133                 }
1134
1135                 d = ic_first_dev;
1136
1137                 timeout = timeout CONF_TIMEOUT_MULT;
1138                 if (timeout > CONF_TIMEOUT_MAX)
1139                         timeout = CONF_TIMEOUT_MAX;
1140
1141                 printk(".");
1142         }
1143
1144 #ifdef IPCONFIG_BOOTP
1145         if (do_bootp)
1146                 ic_bootp_cleanup();
1147 #endif
1148 #ifdef IPCONFIG_RARP
1149         if (do_rarp)
1150                 ic_rarp_cleanup();
1151 #endif
1152
1153         if (!ic_got_reply) {
1154                 ic_myaddr = NONE;
1155                 return -1;
1156         }
1157
1158         printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1159                 ((ic_got_reply & IC_RARP) ? "RARP"
1160                  : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1161                 NIPQUAD(ic_servaddr));
1162         printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1163
1164         return 0;
1165 }
1166
1167 #endif /* IPCONFIG_DYNAMIC */
1168
1169 #ifdef CONFIG_PROC_FS
1170
1171 static int pnp_seq_show(struct seq_file *seq, void *v)
1172 {
1173         int i;
1174
1175         if (ic_proto_used & IC_PROTO)
1176                 seq_printf(seq, "#PROTO: %s\n",
1177                            (ic_proto_used & IC_RARP) ? "RARP"
1178                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1179         else
1180                 seq_puts(seq, "#MANUAL\n");
1181
1182         if (ic_domain[0])
1183                 seq_printf(seq,
1184                            "domain %s\n", ic_domain);
1185         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1186                 if (ic_nameservers[i] != NONE)
1187                         seq_printf(seq,
1188                                    "nameserver %u.%u.%u.%u\n",
1189                                    NIPQUAD(ic_nameservers[i]));
1190         }
1191         if (ic_servaddr != NONE)
1192                 seq_printf(seq,
1193                            "bootserver %u.%u.%u.%u\n",
1194                            NIPQUAD(ic_servaddr));
1195         return 0;
1196 }
1197
1198 static int pnp_seq_open(struct inode *indoe, struct file *file)
1199 {
1200         return single_open(file, pnp_seq_show, NULL);
1201 }
1202
1203 static struct file_operations pnp_seq_fops = {
1204         .owner          = THIS_MODULE,
1205         .open           = pnp_seq_open,
1206         .read           = seq_read,
1207         .llseek         = seq_lseek,
1208         .release        = single_release,
1209 };
1210 #endif /* CONFIG_PROC_FS */
1211
1212 /*
1213  *  Extract IP address from the parameter string if needed. Note that we
1214  *  need to have root_server_addr set _before_ IPConfig gets called as it
1215  *  can override it.
1216  */
1217 __be32 __init root_nfs_parse_addr(char *name)
1218 {
1219         __be32 addr;
1220         int octets = 0;
1221         char *cp, *cq;
1222
1223         cp = cq = name;
1224         while (octets < 4) {
1225                 while (*cp >= '0' && *cp <= '9')
1226                         cp++;
1227                 if (cp == cq || cp - cq > 3)
1228                         break;
1229                 if (*cp == '.' || octets == 3)
1230                         octets++;
1231                 if (octets < 4)
1232                         cp++;
1233                 cq = cp;
1234         }
1235         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1236                 if (*cp == ':')
1237                         *cp++ = '\0';
1238                 addr = in_aton(name);
1239                 memmove(name, cp, strlen(cp) + 1);
1240         } else
1241                 addr = NONE;
1242
1243         return addr;
1244 }
1245
1246 /*
1247  *      IP Autoconfig dispatcher.
1248  */
1249
1250 static int __init ip_auto_config(void)
1251 {
1252         __be32 addr;
1253
1254 #ifdef CONFIG_PROC_FS
1255         proc_net_fops_create("pnp", S_IRUGO, &pnp_seq_fops);
1256 #endif /* CONFIG_PROC_FS */
1257
1258         if (!ic_enable)
1259                 return 0;
1260
1261         DBG(("IP-Config: Entered.\n"));
1262 #ifdef IPCONFIG_DYNAMIC
1263  try_try_again:
1264 #endif
1265         /* Give hardware a chance to settle */
1266         msleep(CONF_PRE_OPEN);
1267
1268         /* Setup all network devices */
1269         if (ic_open_devs() < 0)
1270                 return -1;
1271
1272         /* Give drivers a chance to settle */
1273         ssleep(CONF_POST_OPEN);
1274
1275         /*
1276          * If the config information is insufficient (e.g., our IP address or
1277          * IP address of the boot server is missing or we have multiple network
1278          * interfaces and no default was set), use BOOTP or RARP to get the
1279          * missing values.
1280          */
1281         if (ic_myaddr == NONE ||
1282 #ifdef CONFIG_ROOT_NFS
1283             (MAJOR(ROOT_DEV) == UNNAMED_MAJOR
1284              && root_server_addr == NONE
1285              && ic_servaddr == NONE) ||
1286 #endif
1287             ic_first_dev->next) {
1288 #ifdef IPCONFIG_DYNAMIC
1289
1290                 int retries = CONF_OPEN_RETRIES;
1291
1292                 if (ic_dynamic() < 0) {
1293                         ic_close_devs();
1294
1295                         /*
1296                          * I don't know why, but sometimes the
1297                          * eepro100 driver (at least) gets upset and
1298                          * doesn't work the first time it's opened.
1299                          * But then if you close it and reopen it, it
1300                          * works just fine.  So we need to try that at
1301                          * least once before giving up.
1302                          *
1303                          * Also, if the root will be NFS-mounted, we
1304                          * have nowhere to go if DHCP fails.  So we
1305                          * just have to keep trying forever.
1306                          *
1307                          *                              -- Chip
1308                          */
1309 #ifdef CONFIG_ROOT_NFS
1310                         if (ROOT_DEV ==  Root_NFS) {
1311                                 printk(KERN_ERR
1312                                         "IP-Config: Retrying forever (NFS root)...\n");
1313                                 goto try_try_again;
1314                         }
1315 #endif
1316
1317                         if (--retries) {
1318                                 printk(KERN_ERR
1319                                        "IP-Config: Reopening network devices...\n");
1320                                 goto try_try_again;
1321                         }
1322
1323                         /* Oh, well.  At least we tried. */
1324                         printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1325                         return -1;
1326                 }
1327 #else /* !DYNAMIC */
1328                 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1329                 ic_close_devs();
1330                 return -1;
1331 #endif /* IPCONFIG_DYNAMIC */
1332         } else {
1333                 /* Device selected manually or only one device -> use it */
1334                 ic_dev = ic_first_dev->dev;
1335         }
1336
1337         addr = root_nfs_parse_addr(root_server_path);
1338         if (root_server_addr == NONE)
1339                 root_server_addr = addr;
1340
1341         /*
1342          * Use defaults whereever applicable.
1343          */
1344         if (ic_defaults() < 0)
1345                 return -1;
1346
1347         /*
1348          * Close all network devices except the device we've
1349          * autoconfigured and set up routes.
1350          */
1351         ic_close_devs();
1352         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1353                 return -1;
1354
1355         /*
1356          * Record which protocol was actually used.
1357          */
1358 #ifdef IPCONFIG_DYNAMIC
1359         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1360 #endif
1361
1362 #ifndef IPCONFIG_SILENT
1363         /*
1364          * Clue in the operator.
1365          */
1366         printk("IP-Config: Complete:");
1367         printk("\n      device=%s", ic_dev->name);
1368         printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1369         printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1370         printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1371         printk(",\n     host=%s, domain=%s, nis-domain=%s",
1372                utsname()->nodename, ic_domain, utsname()->domainname);
1373         printk(",\n     bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1374         printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1375         printk(", rootpath=%s", root_server_path);
1376         printk("\n");
1377 #endif /* !SILENT */
1378
1379         return 0;
1380 }
1381
1382 late_initcall(ip_auto_config);
1383
1384
1385 /*
1386  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1387  *  command line parameter. It consists of option fields separated by colons in
1388  *  the following order:
1389  *
1390  *  <client-ip>:<server-ip>:<gw-ip>:<netmask>:<host name>:<device>:<PROTO>
1391  *
1392  *  Any of the fields can be empty which means to use a default value:
1393  *      <client-ip>     - address given by BOOTP or RARP
1394  *      <server-ip>     - address of host returning BOOTP or RARP packet
1395  *      <gw-ip>         - none, or the address returned by BOOTP
1396  *      <netmask>       - automatically determined from <client-ip>, or the
1397  *                        one returned by BOOTP
1398  *      <host name>     - <client-ip> in ASCII notation, or the name returned
1399  *                        by BOOTP
1400  *      <device>        - use all available devices
1401  *      <PROTO>:
1402  *         off|none         - don't do autoconfig at all (DEFAULT)
1403  *         on|any           - use any configured protocol
1404  *         dhcp|bootp|rarp  - use only the specified protocol
1405  *         both             - use both BOOTP and RARP (not DHCP)
1406  */
1407 static int __init ic_proto_name(char *name)
1408 {
1409         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1410                 return 1;
1411         }
1412 #ifdef CONFIG_IP_PNP_DHCP
1413         else if (!strcmp(name, "dhcp")) {
1414                 ic_proto_enabled &= ~IC_RARP;
1415                 return 1;
1416         }
1417 #endif
1418 #ifdef CONFIG_IP_PNP_BOOTP
1419         else if (!strcmp(name, "bootp")) {
1420                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1421                 return 1;
1422         }
1423 #endif
1424 #ifdef CONFIG_IP_PNP_RARP
1425         else if (!strcmp(name, "rarp")) {
1426                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1427                 return 1;
1428         }
1429 #endif
1430 #ifdef IPCONFIG_DYNAMIC
1431         else if (!strcmp(name, "both")) {
1432                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1433                 return 1;
1434         }
1435 #endif
1436         return 0;
1437 }
1438
1439 static int __init ip_auto_config_setup(char *addrs)
1440 {
1441         char *cp, *ip, *dp;
1442         int num = 0;
1443
1444         ic_set_manually = 1;
1445
1446         ic_enable = (*addrs &&
1447                 (strcmp(addrs, "off") != 0) &&
1448                 (strcmp(addrs, "none") != 0));
1449         if (!ic_enable)
1450                 return 1;
1451
1452         if (ic_proto_name(addrs))
1453                 return 1;
1454
1455         /* Parse the whole string */
1456         ip = addrs;
1457         while (ip && *ip) {
1458                 if ((cp = strchr(ip, ':')))
1459                         *cp++ = '\0';
1460                 if (strlen(ip) > 0) {
1461                         DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1462                         switch (num) {
1463                         case 0:
1464                                 if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1465                                         ic_myaddr = NONE;
1466                                 break;
1467                         case 1:
1468                                 if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1469                                         ic_servaddr = NONE;
1470                                 break;
1471                         case 2:
1472                                 if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1473                                         ic_gateway = NONE;
1474                                 break;
1475                         case 3:
1476                                 if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1477                                         ic_netmask = NONE;
1478                                 break;
1479                         case 4:
1480                                 if ((dp = strchr(ip, '.'))) {
1481                                         *dp++ = '\0';
1482                                         strlcpy(utsname()->domainname, dp,
1483                                                 sizeof(utsname()->domainname));
1484                                 }
1485                                 strlcpy(utsname()->nodename, ip,
1486                                         sizeof(utsname()->nodename));
1487                                 ic_host_name_set = 1;
1488                                 break;
1489                         case 5:
1490                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1491                                 break;
1492                         case 6:
1493                                 ic_proto_name(ip);
1494                                 break;
1495                         }
1496                 }
1497                 ip = cp;
1498                 num++;
1499         }
1500
1501         return 1;
1502 }
1503
1504 static int __init nfsaddrs_config_setup(char *addrs)
1505 {
1506         return ip_auto_config_setup(addrs);
1507 }
1508
1509 __setup("ip=", ip_auto_config_setup);
1510 __setup("nfsaddrs=", nfsaddrs_config_setup);