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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/config.h>
  35 #include <linux/types.h>
  36 #include <linux/string.h>
  37 #include <linux/kernel.h>
  38 #include <linux/jiffies.h>
  39 #include <linux/random.h>
  40 #include <linux/init.h>
  41 #include <linux/utsname.h>
  42 #include <linux/in.h>
  43 #include <linux/if.h>
  44 #include <linux/inet.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 <net/arp.h>
  58 #include <net/ip.h>
  59 #include <net/ipconfig.h>
  60
  61 #include <asm/uaccess.h>
  62 #include <net/checksum.h>
  63 #include <asm/processor.h>
  64
  65 /* Define this to allow debugging output */
  66 #undef IPCONFIG_DEBUG
  67
  68 #ifdef IPCONFIG_DEBUG
  69 #define DBG(x) printk x
  70 #else
  71 #define DBG(x) do { } while(0)
  72 #endif
  73
  74 #if defined(CONFIG_IP_PNP_DHCP)
  75 #define IPCONFIG_DHCP
  76 #endif
  77 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
  78 #define IPCONFIG_BOOTP
  79 #endif
  80 #if defined(CONFIG_IP_PNP_RARP)
  81 #define IPCONFIG_RARP
  82 #endif
  83 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
  84 #define IPCONFIG_DYNAMIC
  85 #endif
  86
  87 /* Define the friendly delay before and after opening net devices */
  88 #define CONF_PRE_OPEN           500     /* Before opening: 1/2 second */
  89 #define CONF_POST_OPEN          1       /* After opening: 1 second */
  90
  91 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
  92 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
  93 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
  94 #define CONF_INTER_TIMEOUT      (HZ/2)  /* Inter-device timeout: 1/2 second */
  95 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
  96 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
  97 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
  98 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
  99 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
 100                                            - '3' from resolv.h */
 101
 102
 103 /*
 104  * Public IP configuration
 105  */
 106
 107 /* This is used by platforms which might be able to set the ipconfig
 108  * variables using firmware environment vars.  If this is set, it will
 109  * ignore such firmware variables.
 110  */
 111 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
 112
 113 static int ic_enable __initdata = 0;            /* IP config enabled? */
 114
 115 /* Protocol choice */
 116 int ic_proto_enabled __initdata = 0
 117 #ifdef IPCONFIG_BOOTP
 118                         | IC_BOOTP
 119 #endif
 120 #ifdef CONFIG_IP_PNP_DHCP
 121                         | IC_USE_DHCP
 122 #endif
 123 #ifdef IPCONFIG_RARP
 124                         | IC_RARP
 125 #endif
 126                         ;
 127
 128 static int ic_host_name_set __initdata = 0;     /* Host name set by us? */
 129
 130 u32 ic_myaddr = INADDR_NONE;            /* My IP address */
 131 static u32 ic_netmask = INADDR_NONE;    /* Netmask for local subnet */
 132 u32 ic_gateway = INADDR_NONE;   /* Gateway IP address */
 133
 134 u32 ic_servaddr = INADDR_NONE;  /* Boot server IP address */
 135
 136 u32 root_server_addr = INADDR_NONE;     /* Address of NFS server */
 137 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
 138
 139 /* Persistent data: */
 140
 141 static int ic_proto_used;                       /* Protocol used, if any */
 142 static u32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
 143 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
 144
 145 /*
 146  * Private state.
 147  */
 148
 149 /* Name of user-selected boot device */
 150 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 151
 152 /* Protocols supported by available interfaces */
 153 static int ic_proto_have_if __initdata = 0;
 154
 155 #ifdef IPCONFIG_DYNAMIC
 156 static DEFINE_SPINLOCK(ic_recv_lock);
 157 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
 158 #endif
 159 #ifdef IPCONFIG_DHCP
 160 static int ic_dhcp_msgtype __initdata = 0;      /* DHCP msg type received */
 161 #endif
 162
 163
 164 /*
 165  *      Network devices
 166  */
 167
 168 struct ic_device {
 169         struct ic_device *next;
 170         struct net_device *dev;
 171         unsigned short flags;
 172         short able;
 173         u32 xid;
 174 };
 175
 176 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
 177 static struct net_device *ic_dev __initdata = NULL;     /* Selected device */
 178
 179 static int __init ic_open_devs(void)
 180 {
 181         struct ic_device *d, **last;
 182         struct net_device *dev;
 183         unsigned short oflags;
 184
 185         last = &ic_first_dev;
 186         rtnl_shlock();
 187
 188         /* bring loopback device up first */
 189         if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0)
 190                 printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name);
 191
 192         for (dev = dev_base; dev; dev = dev->next) {
 193                 if (dev == &loopback_dev)
 194                         continue;
 195                 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 196                     (!(dev->flags & IFF_LOOPBACK) &&
 197                      (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 198                      strncmp(dev->name, "dummy", 5))) {
 199                         int able = 0;
 200                         if (dev->mtu >= 364)
 201                                 able |= IC_BOOTP;
 202                         else
 203                                 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
 204                         if (!(dev->flags & IFF_NOARP))
 205                                 able |= IC_RARP;
 206                         able &= ic_proto_enabled;
 207                         if (ic_proto_enabled && !able)
 208                                 continue;
 209                         oflags = dev->flags;
 210                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
 211                                 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
 212                                 continue;
 213                         }
 214                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 215                                 rtnl_shunlock();
 216                                 return -1;
 217                         }
 218                         d->dev = dev;
 219                         *last = d;
 220                         last = &d->next;
 221                         d->flags = oflags;
 222                         d->able = able;
 223                         if (able & IC_BOOTP)
 224                                 get_random_bytes(&d->xid, sizeof(u32));
 225                         else
 226                                 d->xid = 0;
 227                         ic_proto_have_if |= able;
 228                         DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
 229                                 dev->name, able, d->xid));
 230                 }
 231         }
 232         rtnl_shunlock();
 233
 234         *last = NULL;
 235
 236         if (!ic_first_dev) {
 237                 if (user_dev_name[0])
 238                         printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
 239                 else
 240                         printk(KERN_ERR "IP-Config: No network devices available.\n");
 241                 return -1;
 242         }
 243         return 0;
 244 }
 245
 246 static void __init ic_close_devs(void)
 247 {
 248         struct ic_device *d, *next;
 249         struct net_device *dev;
 250
 251         rtnl_shlock();
 252         next = ic_first_dev;
 253         while ((d = next)) {
 254                 next = d->next;
 255                 dev = d->dev;
 256                 if (dev != ic_dev) {
 257                         DBG(("IP-Config: Downing %s\n", dev->name));
 258                         dev_change_flags(dev, d->flags);
 259                 }
 260                 kfree(d);
 261         }
 262         rtnl_shunlock();
 263 }
 264
 265 /*
 266  *      Interface to various network functions.
 267  */
 268
 269 static inline void
 270 set_sockaddr(struct sockaddr_in *sin, u32 addr, u16 port)
 271 {
 272         sin->sin_family = AF_INET;
 273         sin->sin_addr.s_addr = addr;
 274         sin->sin_port = port;
 275 }
 276
 277 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
 278 {
 279         int res;
 280
 281         mm_segment_t oldfs = get_fs();
 282         set_fs(get_ds());
 283         res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
 284         set_fs(oldfs);
 285         return res;
 286 }
 287
 288 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
 289 {
 290         int res;
 291
 292         mm_segment_t oldfs = get_fs();
 293         set_fs(get_ds());
 294         res = ip_rt_ioctl(cmd, (void __user *) arg);
 295         set_fs(oldfs);
 296         return res;
 297 }
 298
 299 /*
 300  *      Set up interface addresses and routes.
 301  */
 302
 303 static int __init ic_setup_if(void)
 304 {
 305         struct ifreq ir;
 306         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 307         int err;
 308
 309         memset(&ir, 0, sizeof(ir));
 310         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
 311         set_sockaddr(sin, ic_myaddr, 0);
 312         if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
 313                 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
 314                 return -1;
 315         }
 316         set_sockaddr(sin, ic_netmask, 0);
 317         if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
 318                 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
 319                 return -1;
 320         }
 321         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 322         if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
 323                 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
 324                 return -1;
 325         }
 326         return 0;
 327 }
 328
 329 static int __init ic_setup_routes(void)
 330 {
 331         /* No need to setup device routes, only the default route... */
 332
 333         if (ic_gateway != INADDR_NONE) {
 334                 struct rtentry rm;
 335                 int err;
 336
 337                 memset(&rm, 0, sizeof(rm));
 338                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 339                         printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
 340                         return -1;
 341                 }
 342                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 343                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 344                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 345                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 346                 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
 347                         printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
 348                         return -1;
 349                 }
 350         }
 351
 352         return 0;
 353 }
 354
 355 /*
 356  *      Fill in default values for all missing parameters.
 357  */
 358
 359 static int __init ic_defaults(void)
 360 {
 361         /*
 362          *      At this point we have no userspace running so need not
 363          *      claim locks on system_utsname
 364          */
 365
 366         if (!ic_host_name_set)
 367                 sprintf(system_utsname.nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
 368
 369         if (root_server_addr == INADDR_NONE)
 370                 root_server_addr = ic_servaddr;
 371
 372         if (ic_netmask == INADDR_NONE) {
 373                 if (IN_CLASSA(ntohl(ic_myaddr)))
 374                         ic_netmask = htonl(IN_CLASSA_NET);
 375                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 376                         ic_netmask = htonl(IN_CLASSB_NET);
 377                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 378                         ic_netmask = htonl(IN_CLASSC_NET);
 379                 else {
 380                         printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
 381                                 NIPQUAD(ic_myaddr));
 382                         return -1;
 383                 }
 384                 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
 385         }
 386
 387         return 0;
 388 }
 389
 390 /*
 391  *      RARP support.
 392  */
 393
 394 #ifdef IPCONFIG_RARP
 395
 396 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt);
 397
 398 static struct packet_type rarp_packet_type __initdata = {
 399         .type = __constant_htons(ETH_P_RARP),
 400         .func = ic_rarp_recv,
 401 };
 402
 403 static inline void ic_rarp_init(void)
 404 {
 405         dev_add_pack(&rarp_packet_type);
 406 }
 407
 408 static inline void ic_rarp_cleanup(void)
 409 {
 410         dev_remove_pack(&rarp_packet_type);
 411 }
 412
 413 /*
 414  *  Process received RARP packet.
 415  */
 416 static int __init
 417 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt)
 418 {
 419         struct arphdr *rarp;
 420         unsigned char *rarp_ptr;
 421         unsigned long sip, tip;
 422         unsigned char *sha, *tha;               /* s for "source", t for "target" */
 423         struct ic_device *d;
 424
 425         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 426                 return NET_RX_DROP;
 427
 428         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 429                 goto drop;
 430
 431         /* Basic sanity checks can be done without the lock.  */
 432         rarp = (struct arphdr *)skb->h.raw;
 433
 434         /* If this test doesn't pass, it's not IP, or we should
 435          * ignore it anyway.
 436          */
 437         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 438                 goto drop;
 439
 440         /* If it's not a RARP reply, delete it. */
 441         if (rarp->ar_op != htons(ARPOP_RREPLY))
 442                 goto drop;
 443
 444         /* If it's not Ethernet, delete it. */
 445         if (rarp->ar_pro != htons(ETH_P_IP))
 446                 goto drop;
 447
 448         if (!pskb_may_pull(skb,
 449                            sizeof(struct arphdr) +
 450                            (2 * dev->addr_len) +
 451                            (2 * 4)))
 452                 goto drop;
 453
 454         /* OK, it is all there and looks valid, process... */
 455         rarp = (struct arphdr *)skb->h.raw;
 456         rarp_ptr = (unsigned char *) (rarp + 1);
 457
 458         /* One reply at a time, please. */
 459         spin_lock(&ic_recv_lock);
 460
 461         /* If we already have a reply, just drop the packet */
 462         if (ic_got_reply)
 463                 goto drop_unlock;
 464
 465         /* Find the ic_device that the packet arrived on */
 466         d = ic_first_dev;
 467         while (d && d->dev != dev)
 468                 d = d->next;
 469         if (!d)
 470                 goto drop_unlock;       /* should never happen */
 471
 472         /* Extract variable-width fields */
 473         sha = rarp_ptr;
 474         rarp_ptr += dev->addr_len;
 475         memcpy(&sip, rarp_ptr, 4);
 476         rarp_ptr += 4;
 477         tha = rarp_ptr;
 478         rarp_ptr += dev->addr_len;
 479         memcpy(&tip, rarp_ptr, 4);
 480
 481         /* Discard packets which are not meant for us. */
 482         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 483                 goto drop_unlock;
 484
 485         /* Discard packets which are not from specified server. */
 486         if (ic_servaddr != INADDR_NONE && ic_servaddr != sip)
 487                 goto drop_unlock;
 488
 489         /* We have a winner! */
 490         ic_dev = dev;
 491         if (ic_myaddr == INADDR_NONE)
 492                 ic_myaddr = tip;
 493         ic_servaddr = sip;
 494         ic_got_reply = IC_RARP;
 495
 496 drop_unlock:
 497         /* Show's over.  Nothing to see here.  */
 498         spin_unlock(&ic_recv_lock);
 499
 500 drop:
 501         /* Throw the packet out. */
 502         kfree_skb(skb);
 503         return 0;
 504 }
 505
 506
 507 /*
 508  *  Send RARP request packet over a single interface.
 509  */
 510 static void __init ic_rarp_send_if(struct ic_device *d)
 511 {
 512         struct net_device *dev = d->dev;
 513         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 514                  dev->dev_addr, dev->dev_addr);
 515 }
 516 #endif
 517
 518 /*
 519  *      DHCP/BOOTP support.
 520  */
 521
 522 #ifdef IPCONFIG_BOOTP
 523
 524 struct bootp_pkt {              /* BOOTP packet format */
 525         struct iphdr iph;       /* IP header */
 526         struct udphdr udph;     /* UDP header */
 527         u8 op;                  /* 1=request, 2=reply */
 528         u8 htype;               /* HW address type */
 529         u8 hlen;                /* HW address length */
 530         u8 hops;                /* Used only by gateways */
 531         u32 xid;                /* Transaction ID */
 532         u16 secs;               /* Seconds since we started */
 533         u16 flags;              /* Just what it says */
 534         u32 client_ip;          /* Client's IP address if known */
 535         u32 your_ip;            /* Assigned IP address */
 536         u32 server_ip;          /* (Next, e.g. NFS) Server's IP address */
 537         u32 relay_ip;           /* IP address of BOOTP relay */
 538         u8 hw_addr[16];         /* Client's HW address */
 539         u8 serv_name[64];       /* Server host name */
 540         u8 boot_file[128];      /* Name of boot file */
 541         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 542 };
 543
 544 /* packet ops */
 545 #define BOOTP_REQUEST   1
 546 #define BOOTP_REPLY     2
 547
 548 /* DHCP message types */
 549 #define DHCPDISCOVER    1
 550 #define DHCPOFFER       2
 551 #define DHCPREQUEST     3
 552 #define DHCPDECLINE     4
 553 #define DHCPACK         5
 554 #define DHCPNAK         6
 555 #define DHCPRELEASE     7
 556 #define DHCPINFORM      8
 557
 558 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt);
 559
 560 static struct packet_type bootp_packet_type __initdata = {
 561         .type = __constant_htons(ETH_P_IP),
 562         .func = ic_bootp_recv,
 563 };
 564
 565
 566 /*
 567  *  Initialize DHCP/BOOTP extension fields in the request.
 568  */
 569
 570 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 571
 572 #ifdef IPCONFIG_DHCP
 573
 574 static void __init
 575 ic_dhcp_init_options(u8 *options)
 576 {
 577         u8 mt = ((ic_servaddr == INADDR_NONE)
 578                  ? DHCPDISCOVER : DHCPREQUEST);
 579         u8 *e = options;
 580
 581 #ifdef IPCONFIG_DEBUG
 582         printk("DHCP: Sending message type %d\n", mt);
 583 #endif
 584
 585         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 586         e += 4;
 587
 588         *e++ = 53;              /* DHCP message type */
 589         *e++ = 1;
 590         *e++ = mt;
 591
 592         if (mt == DHCPREQUEST) {
 593                 *e++ = 54;      /* Server ID (IP address) */
 594                 *e++ = 4;
 595                 memcpy(e, &ic_servaddr, 4);
 596                 e += 4;
 597
 598                 *e++ = 50;      /* Requested IP address */
 599                 *e++ = 4;
 600                 memcpy(e, &ic_myaddr, 4);
 601                 e += 4;
 602         }
 603
 604         /* always? */
 605         {
 606                 static const u8 ic_req_params[] = {
 607                         1,      /* Subnet mask */
 608                         3,      /* Default gateway */
 609                         6,      /* DNS server */
 610                         12,     /* Host name */
 611                         15,     /* Domain name */
 612                         17,     /* Boot path */
 613                         40,     /* NIS domain name */
 614                 };
 615
 616                 *e++ = 55;      /* Parameter request list */
 617                 *e++ = sizeof(ic_req_params);
 618                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 619                 e += sizeof(ic_req_params);
 620         }
 621
 622         *e++ = 255;     /* End of the list */
 623 }
 624
 625 #endif /* IPCONFIG_DHCP */
 626
 627 static void __init ic_bootp_init_ext(u8 *e)
 628 {
 629         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 630         e += 4;
 631         *e++ = 1;               /* Subnet mask request */
 632         *e++ = 4;
 633         e += 4;
 634         *e++ = 3;               /* Default gateway request */
 635         *e++ = 4;
 636         e += 4;
 637         *e++ = 5;               /* Name server request */
 638         *e++ = 8;
 639         e += 8;
 640         *e++ = 12;              /* Host name request */
 641         *e++ = 32;
 642         e += 32;
 643         *e++ = 40;              /* NIS Domain name request */
 644         *e++ = 32;
 645         e += 32;
 646         *e++ = 17;              /* Boot path */
 647         *e++ = 40;
 648         e += 40;
 649
 650         *e++ = 57;              /* set extension buffer size for reply */
 651         *e++ = 2;
 652         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 653         *e++ = 150;
 654
 655         *e++ = 255;             /* End of the list */
 656 }
 657
 658
 659 /*
 660  *  Initialize the DHCP/BOOTP mechanism.
 661  */
 662 static inline void ic_bootp_init(void)
 663 {
 664         int i;
 665
 666         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 667                 ic_nameservers[i] = INADDR_NONE;
 668
 669         dev_add_pack(&bootp_packet_type);
 670 }
 671
 672
 673 /*
 674  *  DHCP/BOOTP cleanup.
 675  */
 676 static inline void ic_bootp_cleanup(void)
 677 {
 678         dev_remove_pack(&bootp_packet_type);
 679 }
 680
 681
 682 /*
 683  *  Send DHCP/BOOTP request to single interface.
 684  */
 685 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 686 {
 687         struct net_device *dev = d->dev;
 688         struct sk_buff *skb;
 689         struct bootp_pkt *b;
 690         int hh_len = LL_RESERVED_SPACE(dev);
 691         struct iphdr *h;
 692
 693         /* Allocate packet */
 694         skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
 695         if (!skb)
 696                 return;
 697         skb_reserve(skb, hh_len);
 698         b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
 699         memset(b, 0, sizeof(struct bootp_pkt));
 700
 701         /* Construct IP header */
 702         skb->nh.iph = h = &b->iph;
 703         h->version = 4;
 704         h->ihl = 5;
 705         h->tot_len = htons(sizeof(struct bootp_pkt));
 706         h->frag_off = htons(IP_DF);
 707         h->ttl = 64;
 708         h->protocol = IPPROTO_UDP;
 709         h->daddr = INADDR_BROADCAST;
 710         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 711
 712         /* Construct UDP header */
 713         b->udph.source = htons(68);
 714         b->udph.dest = htons(67);
 715         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 716         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 717
 718         /* Construct DHCP/BOOTP header */
 719         b->op = BOOTP_REQUEST;
 720         if (dev->type < 256) /* check for false types */
 721                 b->htype = dev->type;
 722         else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
 723                 b->htype = ARPHRD_IEEE802;
 724         else if (dev->type == ARPHRD_FDDI)
 725                 b->htype = ARPHRD_ETHER;
 726         else {
 727                 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
 728                 b->htype = dev->type; /* can cause undefined behavior */
 729         }
 730         b->hlen = dev->addr_len;
 731         b->your_ip = INADDR_NONE;
 732         b->server_ip = INADDR_NONE;
 733         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 734         b->secs = htons(jiffies_diff / HZ);
 735         b->xid = d->xid;
 736
 737         /* add DHCP options or BOOTP extensions */
 738 #ifdef IPCONFIG_DHCP
 739         if (ic_proto_enabled & IC_USE_DHCP)
 740                 ic_dhcp_init_options(b->exten);
 741         else
 742 #endif
 743                 ic_bootp_init_ext(b->exten);
 744
 745         /* Chain packet down the line... */
 746         skb->dev = dev;
 747         skb->protocol = htons(ETH_P_IP);
 748         if ((dev->hard_header &&
 749              dev->hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) ||
 750             dev_queue_xmit(skb) < 0)
 751                 printk("E");
 752 }
 753
 754
 755 /*
 756  *  Copy BOOTP-supplied string if not already set.
 757  */
 758 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 759 {
 760         if (!len)
 761                 return 0;
 762         if (len > max-1)
 763                 len = max-1;
 764         memcpy(dest, src, len);
 765         dest[len] = '\0';
 766         return 1;
 767 }
 768
 769
 770 /*
 771  *  Process BOOTP extensions.
 772  */
 773 static void __init ic_do_bootp_ext(u8 *ext)
 774 {
 775        u8 servers;
 776        int i;
 777
 778 #ifdef IPCONFIG_DEBUG
 779         u8 *c;
 780
 781         printk("DHCP/BOOTP: Got extension %d:",*ext);
 782         for(c=ext+2; c<ext+2+ext[1]; c++)
 783                 printk(" %02x", *c);
 784         printk("\n");
 785 #endif
 786
 787         switch (*ext++) {
 788                 case 1:         /* Subnet mask */
 789                         if (ic_netmask == INADDR_NONE)
 790                                 memcpy(&ic_netmask, ext+1, 4);
 791                         break;
 792                 case 3:         /* Default gateway */
 793                         if (ic_gateway == INADDR_NONE)
 794                                 memcpy(&ic_gateway, ext+1, 4);
 795                         break;
 796                 case 6:         /* DNS server */
 797                         servers= *ext/4;
 798                         if (servers > CONF_NAMESERVERS_MAX)
 799                                 servers = CONF_NAMESERVERS_MAX;
 800                         for (i = 0; i < servers; i++) {
 801                                 if (ic_nameservers[i] == INADDR_NONE)
 802                                         memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 803                         }
 804                         break;
 805                 case 12:        /* Host name */
 806                         ic_bootp_string(system_utsname.nodename, ext+1, *ext, __NEW_UTS_LEN);
 807                         ic_host_name_set = 1;
 808                         break;
 809                 case 15:        /* Domain name (DNS) */
 810                         ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
 811                         break;
 812                 case 17:        /* Root path */
 813                         if (!root_server_path[0])
 814                                 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
 815                         break;
 816                 case 40:        /* NIS Domain name (_not_ DNS) */
 817                         ic_bootp_string(system_utsname.domainname, ext+1, *ext, __NEW_UTS_LEN);
 818                         break;
 819         }
 820 }
 821
 822
 823 /*
 824  *  Receive BOOTP reply.
 825  */
 826 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt)
 827 {
 828         struct bootp_pkt *b;
 829         struct iphdr *h;
 830         struct ic_device *d;
 831         int len, ext_len;
 832
 833         /* Perform verifications before taking the lock.  */
 834         if (skb->pkt_type == PACKET_OTHERHOST)
 835                 goto drop;
 836
 837         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 838                 return NET_RX_DROP;
 839
 840         if (!pskb_may_pull(skb,
 841                            sizeof(struct iphdr) +
 842                            sizeof(struct udphdr)))
 843                 goto drop;
 844
 845         b = (struct bootp_pkt *) skb->nh.iph;
 846         h = &b->iph;
 847
 848         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
 849                 goto drop;
 850
 851         /* Fragments are not supported */
 852         if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
 853                 if (net_ratelimit())
 854                         printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
 855                                "reply.\n");
 856                 goto drop;
 857         }
 858
 859         if (skb->len < ntohs(h->tot_len))
 860                 goto drop;
 861
 862         if (ip_fast_csum((char *) h, h->ihl))
 863                 goto drop;
 864
 865         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
 866                 goto drop;
 867
 868         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
 869                 goto drop;
 870
 871         len = ntohs(b->udph.len) - sizeof(struct udphdr);
 872         ext_len = len - (sizeof(*b) -
 873                          sizeof(struct iphdr) -
 874                          sizeof(struct udphdr) -
 875                          sizeof(b->exten));
 876         if (ext_len < 0)
 877                 goto drop;
 878
 879         /* Ok the front looks good, make sure we can get at the rest.  */
 880         if (!pskb_may_pull(skb, skb->len))
 881                 goto drop;
 882
 883         b = (struct bootp_pkt *) skb->nh.iph;
 884         h = &b->iph;
 885
 886         /* One reply at a time, please. */
 887         spin_lock(&ic_recv_lock);
 888
 889         /* If we already have a reply, just drop the packet */
 890         if (ic_got_reply)
 891                 goto drop_unlock;
 892
 893         /* Find the ic_device that the packet arrived on */
 894         d = ic_first_dev;
 895         while (d && d->dev != dev)
 896                 d = d->next;
 897         if (!d)
 898                 goto drop_unlock;  /* should never happen */
 899
 900         /* Is it a reply to our BOOTP request? */
 901         if (b->op != BOOTP_REPLY ||
 902             b->xid != d->xid) {
 903                 if (net_ratelimit())
 904                         printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
 905                                "op[%x] xid[%x]\n",
 906                                b->op, b->xid);
 907                 goto drop_unlock;
 908         }
 909
 910         /* Parse extensions */
 911         if (ext_len >= 4 &&
 912             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
 913                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
 914                 u8 *ext;
 915
 916 #ifdef IPCONFIG_DHCP
 917                 if (ic_proto_enabled & IC_USE_DHCP) {
 918                         u32 server_id = INADDR_NONE;
 919                         int mt = 0;
 920
 921                         ext = &b->exten[4];
 922                         while (ext < end && *ext != 0xff) {
 923                                 u8 *opt = ext++;
 924                                 if (*opt == 0)  /* Padding */
 925                                         continue;
 926                                 ext += *ext + 1;
 927                                 if (ext >= end)
 928                                         break;
 929                                 switch (*opt) {
 930                                 case 53:        /* Message type */
 931                                         if (opt[1])
 932                                                 mt = opt[2];
 933                                         break;
 934                                 case 54:        /* Server ID (IP address) */
 935                                         if (opt[1] >= 4)
 936                                                 memcpy(&server_id, opt + 2, 4);
 937                                         break;
 938                                 };
 939                         }
 940
 941 #ifdef IPCONFIG_DEBUG
 942                         printk("DHCP: Got message type %d\n", mt);
 943 #endif
 944
 945                         switch (mt) {
 946                         case DHCPOFFER:
 947                                 /* While in the process of accepting one offer,
 948                                  * ignore all others.
 949                                  */
 950                                 if (ic_myaddr != INADDR_NONE)
 951                                         goto drop_unlock;
 952
 953                                 /* Let's accept that offer. */
 954                                 ic_myaddr = b->your_ip;
 955                                 ic_servaddr = server_id;
 956 #ifdef IPCONFIG_DEBUG
 957                                 printk("DHCP: Offered address %u.%u.%u.%u",
 958                                        NIPQUAD(ic_myaddr));
 959                                 printk(" by server %u.%u.%u.%u\n",
 960                                        NIPQUAD(ic_servaddr));
 961 #endif
 962                                 /* The DHCP indicated server address takes
 963                                  * precedence over the bootp header one if
 964                                  * they are different.
 965                                  */
 966                                 if ((server_id != INADDR_NONE) &&
 967                                     (b->server_ip != server_id))
 968                                         b->server_ip = ic_servaddr;
 969                                 break;
 970
 971                         case DHCPACK:
 972                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
 973                                         goto drop_unlock;
 974
 975                                 /* Yeah! */
 976                                 break;
 977
 978                         default:
 979                                 /* Urque.  Forget it*/
 980                                 ic_myaddr = INADDR_NONE;
 981                                 ic_servaddr = INADDR_NONE;
 982                                 goto drop_unlock;
 983                         };
 984
 985                         ic_dhcp_msgtype = mt;
 986
 987                 }
 988 #endif /* IPCONFIG_DHCP */
 989
 990                 ext = &b->exten[4];
 991                 while (ext < end && *ext != 0xff) {
 992                         u8 *opt = ext++;
 993                         if (*opt == 0)  /* Padding */
 994                                 continue;
 995                         ext += *ext + 1;
 996                         if (ext < end)
 997                                 ic_do_bootp_ext(opt);
 998                 }
 999         }
1000
1001         /* We have a winner! */
1002         ic_dev = dev;
1003         ic_myaddr = b->your_ip;
1004         ic_servaddr = b->server_ip;
1005         if (ic_gateway == INADDR_NONE && b->relay_ip)
1006                 ic_gateway = b->relay_ip;
1007         if (ic_nameservers[0] == INADDR_NONE)
1008                 ic_nameservers[0] = ic_servaddr;
1009         ic_got_reply = IC_BOOTP;
1010
1011 drop_unlock:
1012         /* Show's over.  Nothing to see here.  */
1013         spin_unlock(&ic_recv_lock);
1014
1015 drop:
1016         /* Throw the packet out. */
1017         kfree_skb(skb);
1018
1019         return 0;
1020 }
1021
1022
1023 #endif
1024
1025
1026 /*
1027  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1028  */
1029
1030 #ifdef IPCONFIG_DYNAMIC
1031
1032 static int __init ic_dynamic(void)
1033 {
1034         int retries;
1035         struct ic_device *d;
1036         unsigned long start_jiffies, timeout, jiff;
1037         int do_bootp = ic_proto_have_if & IC_BOOTP;
1038         int do_rarp = ic_proto_have_if & IC_RARP;
1039
1040         /*
1041          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1042          * This routine gets only called when some pieces of information
1043          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1044          */
1045         if (!ic_proto_enabled) {
1046                 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1047                 return -1;
1048         }
1049
1050 #ifdef IPCONFIG_BOOTP
1051         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1052                 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1053 #endif
1054 #ifdef IPCONFIG_RARP
1055         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1056                 printk(KERN_ERR "RARP: No suitable device found.\n");
1057 #endif
1058
1059         if (!ic_proto_have_if)
1060                 /* Error message already printed */
1061                 return -1;
1062
1063         /*
1064          * Setup protocols
1065          */
1066 #ifdef IPCONFIG_BOOTP
1067         if (do_bootp)
1068                 ic_bootp_init();
1069 #endif
1070 #ifdef IPCONFIG_RARP
1071         if (do_rarp)
1072                 ic_rarp_init();
1073 #endif
1074
1075         /*
1076          * Send requests and wait, until we get an answer. This loop
1077          * seems to be a terrible waste of CPU time, but actually there is
1078          * only one process running at all, so we don't need to use any
1079          * scheduler functions.
1080          * [Actually we could now, but the nothing else running note still
1081          *  applies.. - AC]
1082          */
1083         printk(KERN_NOTICE "Sending %s%s%s requests .",
1084                do_bootp
1085                 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1086                (do_bootp && do_rarp) ? " and " : "",
1087                do_rarp ? "RARP" : "");
1088
1089         start_jiffies = jiffies;
1090         d = ic_first_dev;
1091         retries = CONF_SEND_RETRIES;
1092         get_random_bytes(&timeout, sizeof(timeout));
1093         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1094         for(;;) {
1095 #ifdef IPCONFIG_BOOTP
1096                 if (do_bootp && (d->able & IC_BOOTP))
1097                         ic_bootp_send_if(d, jiffies - start_jiffies);
1098 #endif
1099 #ifdef IPCONFIG_RARP
1100                 if (do_rarp && (d->able & IC_RARP))
1101                         ic_rarp_send_if(d);
1102 #endif
1103
1104                 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1105                 while (time_before(jiffies, jiff) && !ic_got_reply) {
1106                         set_current_state(TASK_UNINTERRUPTIBLE);
1107                         schedule_timeout(1);
1108                 }
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                system_utsname.nodename, ic_domain, system_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(system_utsname.domainname, dp,
1482                                                 sizeof(system_utsname.domainname));
1483                                 }
1484                                 strlcpy(system_utsname.nodename, ip,
1485                                         sizeof(system_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);