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