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