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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/net_namespace.h>
  59 #include <net/arp.h>
  60 #include <net/ip.h>
  61 #include <net/ipconfig.h>
  62 #include <net/route.h>
  63
  64 #include <asm/uaccess.h>
  65 #include <net/checksum.h>
  66 #include <asm/processor.h>
  67
  68 /* Define this to allow debugging output */
  69 #undef IPCONFIG_DEBUG
  70
  71 #ifdef IPCONFIG_DEBUG
  72 #define DBG(x) printk x
  73 #else
  74 #define DBG(x) do { } while(0)
  75 #endif
  76
  77 #if defined(CONFIG_IP_PNP_DHCP)
  78 #define IPCONFIG_DHCP
  79 #endif
  80 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
  81 #define IPCONFIG_BOOTP
  82 #endif
  83 #if defined(CONFIG_IP_PNP_RARP)
  84 #define IPCONFIG_RARP
  85 #endif
  86 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
  87 #define IPCONFIG_DYNAMIC
  88 #endif
  89
  90 /* Define the friendly delay before and after opening net devices */
  91 #define CONF_PRE_OPEN           500     /* Before opening: 1/2 second */
  92 #define CONF_POST_OPEN          1       /* After opening: 1 second */
  93
  94 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
  95 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
  96 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
  97 #define CONF_INTER_TIMEOUT      (HZ/2)  /* Inter-device timeout: 1/2 second */
  98 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
  99 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
 100 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
 101 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
 102 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
 103                                            - '3' from resolv.h */
 104
 105 #define NONE __constant_htonl(INADDR_NONE)
 106
 107 /*
 108  * Public IP configuration
 109  */
 110
 111 /* This is used by platforms which might be able to set the ipconfig
 112  * variables using firmware environment vars.  If this is set, it will
 113  * ignore such firmware variables.
 114  */
 115 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
 116
 117 static int ic_enable __initdata = 0;            /* IP config enabled? */
 118
 119 /* Protocol choice */
 120 int ic_proto_enabled __initdata = 0
 121 #ifdef IPCONFIG_BOOTP
 122                         | IC_BOOTP
 123 #endif
 124 #ifdef CONFIG_IP_PNP_DHCP
 125                         | IC_USE_DHCP
 126 #endif
 127 #ifdef IPCONFIG_RARP
 128                         | IC_RARP
 129 #endif
 130                         ;
 131
 132 static int ic_host_name_set __initdata = 0;     /* Host name set by us? */
 133
 134 __be32 ic_myaddr = NONE;                /* My IP address */
 135 static __be32 ic_netmask = NONE;        /* Netmask for local subnet */
 136 __be32 ic_gateway = NONE;       /* Gateway IP address */
 137
 138 __be32 ic_servaddr = NONE;      /* Boot server IP address */
 139
 140 __be32 root_server_addr = NONE; /* Address of NFS server */
 141 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
 142
 143 /* Persistent data: */
 144
 145 static int ic_proto_used;                       /* Protocol used, if any */
 146 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
 147 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
 148
 149 /*
 150  * Private state.
 151  */
 152
 153 /* Name of user-selected boot device */
 154 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 155
 156 /* Protocols supported by available interfaces */
 157 static int ic_proto_have_if __initdata = 0;
 158
 159 #ifdef IPCONFIG_DYNAMIC
 160 static DEFINE_SPINLOCK(ic_recv_lock);
 161 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
 162 #endif
 163 #ifdef IPCONFIG_DHCP
 164 static int ic_dhcp_msgtype __initdata = 0;      /* DHCP msg type received */
 165 #endif
 166
 167
 168 /*
 169  *      Network devices
 170  */
 171
 172 struct ic_device {
 173         struct ic_device *next;
 174         struct net_device *dev;
 175         unsigned short flags;
 176         short able;
 177         __be32 xid;
 178 };
 179
 180 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
 181 static struct net_device *ic_dev __initdata = NULL;     /* Selected device */
 182
 183 static int __init ic_open_devs(void)
 184 {
 185         struct ic_device *d, **last;
 186         struct net_device *dev;
 187         unsigned short oflags;
 188
 189         last = &ic_first_dev;
 190         rtnl_lock();
 191
 192         /* bring loopback device up first */
 193         if (dev_change_flags(&loopback_dev, loopback_dev.flags | IFF_UP) < 0)
 194                 printk(KERN_ERR "IP-Config: Failed to open %s\n", loopback_dev.name);
 195
 196         for_each_netdev(&init_net, dev) {
 197                 if (dev == &loopback_dev)
 198                         continue;
 199                 if (user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 200                     (!(dev->flags & IFF_LOOPBACK) &&
 201                      (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 202                      strncmp(dev->name, "dummy", 5))) {
 203                         int able = 0;
 204                         if (dev->mtu >= 364)
 205                                 able |= IC_BOOTP;
 206                         else
 207                                 printk(KERN_WARNING "DHCP/BOOTP: Ignoring device %s, MTU %d too small", dev->name, dev->mtu);
 208                         if (!(dev->flags & IFF_NOARP))
 209                                 able |= IC_RARP;
 210                         able &= ic_proto_enabled;
 211                         if (ic_proto_enabled && !able)
 212                                 continue;
 213                         oflags = dev->flags;
 214                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
 215                                 printk(KERN_ERR "IP-Config: Failed to open %s\n", dev->name);
 216                                 continue;
 217                         }
 218                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 219                                 rtnl_unlock();
 220                                 return -1;
 221                         }
 222                         d->dev = dev;
 223                         *last = d;
 224                         last = &d->next;
 225                         d->flags = oflags;
 226                         d->able = able;
 227                         if (able & IC_BOOTP)
 228                                 get_random_bytes(&d->xid, sizeof(__be32));
 229                         else
 230                                 d->xid = 0;
 231                         ic_proto_have_if |= able;
 232                         DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
 233                                 dev->name, able, d->xid));
 234                 }
 235         }
 236         rtnl_unlock();
 237
 238         *last = NULL;
 239
 240         if (!ic_first_dev) {
 241                 if (user_dev_name[0])
 242                         printk(KERN_ERR "IP-Config: Device `%s' not found.\n", user_dev_name);
 243                 else
 244                         printk(KERN_ERR "IP-Config: No network devices available.\n");
 245                 return -1;
 246         }
 247         return 0;
 248 }
 249
 250 static void __init ic_close_devs(void)
 251 {
 252         struct ic_device *d, *next;
 253         struct net_device *dev;
 254
 255         rtnl_lock();
 256         next = ic_first_dev;
 257         while ((d = next)) {
 258                 next = d->next;
 259                 dev = d->dev;
 260                 if (dev != ic_dev) {
 261                         DBG(("IP-Config: Downing %s\n", dev->name));
 262                         dev_change_flags(dev, d->flags);
 263                 }
 264                 kfree(d);
 265         }
 266         rtnl_unlock();
 267 }
 268
 269 /*
 270  *      Interface to various network functions.
 271  */
 272
 273 static inline void
 274 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
 275 {
 276         sin->sin_family = AF_INET;
 277         sin->sin_addr.s_addr = addr;
 278         sin->sin_port = port;
 279 }
 280
 281 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
 282 {
 283         int res;
 284
 285         mm_segment_t oldfs = get_fs();
 286         set_fs(get_ds());
 287         res = devinet_ioctl(cmd, (struct ifreq __user *) arg);
 288         set_fs(oldfs);
 289         return res;
 290 }
 291
 292 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
 293 {
 294         int res;
 295
 296         mm_segment_t oldfs = get_fs();
 297         set_fs(get_ds());
 298         res = ip_rt_ioctl(cmd, (void __user *) arg);
 299         set_fs(oldfs);
 300         return res;
 301 }
 302
 303 /*
 304  *      Set up interface addresses and routes.
 305  */
 306
 307 static int __init ic_setup_if(void)
 308 {
 309         struct ifreq ir;
 310         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 311         int err;
 312
 313         memset(&ir, 0, sizeof(ir));
 314         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
 315         set_sockaddr(sin, ic_myaddr, 0);
 316         if ((err = ic_dev_ioctl(SIOCSIFADDR, &ir)) < 0) {
 317                 printk(KERN_ERR "IP-Config: Unable to set interface address (%d).\n", err);
 318                 return -1;
 319         }
 320         set_sockaddr(sin, ic_netmask, 0);
 321         if ((err = ic_dev_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
 322                 printk(KERN_ERR "IP-Config: Unable to set interface netmask (%d).\n", err);
 323                 return -1;
 324         }
 325         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 326         if ((err = ic_dev_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
 327                 printk(KERN_ERR "IP-Config: Unable to set interface broadcast address (%d).\n", err);
 328                 return -1;
 329         }
 330         return 0;
 331 }
 332
 333 static int __init ic_setup_routes(void)
 334 {
 335         /* No need to setup device routes, only the default route... */
 336
 337         if (ic_gateway != NONE) {
 338                 struct rtentry rm;
 339                 int err;
 340
 341                 memset(&rm, 0, sizeof(rm));
 342                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 343                         printk(KERN_ERR "IP-Config: Gateway not on directly connected network.\n");
 344                         return -1;
 345                 }
 346                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 347                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 348                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 349                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 350                 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
 351                         printk(KERN_ERR "IP-Config: Cannot add default route (%d).\n", err);
 352                         return -1;
 353                 }
 354         }
 355
 356         return 0;
 357 }
 358
 359 /*
 360  *      Fill in default values for all missing parameters.
 361  */
 362
 363 static int __init ic_defaults(void)
 364 {
 365         /*
 366          *      At this point we have no userspace running so need not
 367          *      claim locks on system_utsname
 368          */
 369
 370         if (!ic_host_name_set)
 371                 sprintf(init_utsname()->nodename, "%u.%u.%u.%u", NIPQUAD(ic_myaddr));
 372
 373         if (root_server_addr == NONE)
 374                 root_server_addr = ic_servaddr;
 375
 376         if (ic_netmask == NONE) {
 377                 if (IN_CLASSA(ntohl(ic_myaddr)))
 378                         ic_netmask = htonl(IN_CLASSA_NET);
 379                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 380                         ic_netmask = htonl(IN_CLASSB_NET);
 381                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 382                         ic_netmask = htonl(IN_CLASSC_NET);
 383                 else {
 384                         printk(KERN_ERR "IP-Config: Unable to guess netmask for address %u.%u.%u.%u\n",
 385                                 NIPQUAD(ic_myaddr));
 386                         return -1;
 387                 }
 388                 printk("IP-Config: Guessing netmask %u.%u.%u.%u\n", NIPQUAD(ic_netmask));
 389         }
 390
 391         return 0;
 392 }
 393
 394 /*
 395  *      RARP support.
 396  */
 397
 398 #ifdef IPCONFIG_RARP
 399
 400 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 401
 402 static struct packet_type rarp_packet_type __initdata = {
 403         .type = __constant_htons(ETH_P_RARP),
 404         .func = ic_rarp_recv,
 405 };
 406
 407 static inline void ic_rarp_init(void)
 408 {
 409         dev_add_pack(&rarp_packet_type);
 410 }
 411
 412 static inline void ic_rarp_cleanup(void)
 413 {
 414         dev_remove_pack(&rarp_packet_type);
 415 }
 416
 417 /*
 418  *  Process received RARP packet.
 419  */
 420 static int __init
 421 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 422 {
 423         struct arphdr *rarp;
 424         unsigned char *rarp_ptr;
 425         __be32 sip, tip;
 426         unsigned char *sha, *tha;               /* s for "source", t for "target" */
 427         struct ic_device *d;
 428
 429         if (dev->nd_net != &init_net)
 430                 goto drop;
 431
 432         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 433                 return NET_RX_DROP;
 434
 435         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 436                 goto drop;
 437
 438         /* Basic sanity checks can be done without the lock.  */
 439         rarp = (struct arphdr *)skb_transport_header(skb);
 440
 441         /* If this test doesn't pass, it's not IP, or we should
 442          * ignore it anyway.
 443          */
 444         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 445                 goto drop;
 446
 447         /* If it's not a RARP reply, delete it. */
 448         if (rarp->ar_op != htons(ARPOP_RREPLY))
 449                 goto drop;
 450
 451         /* If it's not Ethernet, delete it. */
 452         if (rarp->ar_pro != htons(ETH_P_IP))
 453                 goto drop;
 454
 455         if (!pskb_may_pull(skb,
 456                            sizeof(struct arphdr) +
 457                            (2 * dev->addr_len) +
 458                            (2 * 4)))
 459                 goto drop;
 460
 461         /* OK, it is all there and looks valid, process... */
 462         rarp = (struct arphdr *)skb_transport_header(skb);
 463         rarp_ptr = (unsigned char *) (rarp + 1);
 464
 465         /* One reply at a time, please. */
 466         spin_lock(&ic_recv_lock);
 467
 468         /* If we already have a reply, just drop the packet */
 469         if (ic_got_reply)
 470                 goto drop_unlock;
 471
 472         /* Find the ic_device that the packet arrived on */
 473         d = ic_first_dev;
 474         while (d && d->dev != dev)
 475                 d = d->next;
 476         if (!d)
 477                 goto drop_unlock;       /* should never happen */
 478
 479         /* Extract variable-width fields */
 480         sha = rarp_ptr;
 481         rarp_ptr += dev->addr_len;
 482         memcpy(&sip, rarp_ptr, 4);
 483         rarp_ptr += 4;
 484         tha = rarp_ptr;
 485         rarp_ptr += dev->addr_len;
 486         memcpy(&tip, rarp_ptr, 4);
 487
 488         /* Discard packets which are not meant for us. */
 489         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 490                 goto drop_unlock;
 491
 492         /* Discard packets which are not from specified server. */
 493         if (ic_servaddr != NONE && ic_servaddr != sip)
 494                 goto drop_unlock;
 495
 496         /* We have a winner! */
 497         ic_dev = dev;
 498         if (ic_myaddr == NONE)
 499                 ic_myaddr = tip;
 500         ic_servaddr = sip;
 501         ic_got_reply = IC_RARP;
 502
 503 drop_unlock:
 504         /* Show's over.  Nothing to see here.  */
 505         spin_unlock(&ic_recv_lock);
 506
 507 drop:
 508         /* Throw the packet out. */
 509         kfree_skb(skb);
 510         return 0;
 511 }
 512
 513
 514 /*
 515  *  Send RARP request packet over a single interface.
 516  */
 517 static void __init ic_rarp_send_if(struct ic_device *d)
 518 {
 519         struct net_device *dev = d->dev;
 520         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 521                  dev->dev_addr, dev->dev_addr);
 522 }
 523 #endif
 524
 525 /*
 526  *      DHCP/BOOTP support.
 527  */
 528
 529 #ifdef IPCONFIG_BOOTP
 530
 531 struct bootp_pkt {              /* BOOTP packet format */
 532         struct iphdr iph;       /* IP header */
 533         struct udphdr udph;     /* UDP header */
 534         u8 op;                  /* 1=request, 2=reply */
 535         u8 htype;               /* HW address type */
 536         u8 hlen;                /* HW address length */
 537         u8 hops;                /* Used only by gateways */
 538         __be32 xid;             /* Transaction ID */
 539         __be16 secs;            /* Seconds since we started */
 540         __be16 flags;           /* Just what it says */
 541         __be32 client_ip;               /* Client's IP address if known */
 542         __be32 your_ip;         /* Assigned IP address */
 543         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
 544         __be32 relay_ip;                /* IP address of BOOTP relay */
 545         u8 hw_addr[16];         /* Client's HW address */
 546         u8 serv_name[64];       /* Server host name */
 547         u8 boot_file[128];      /* Name of boot file */
 548         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 549 };
 550
 551 /* packet ops */
 552 #define BOOTP_REQUEST   1
 553 #define BOOTP_REPLY     2
 554
 555 /* DHCP message types */
 556 #define DHCPDISCOVER    1
 557 #define DHCPOFFER       2
 558 #define DHCPREQUEST     3
 559 #define DHCPDECLINE     4
 560 #define DHCPACK         5
 561 #define DHCPNAK         6
 562 #define DHCPRELEASE     7
 563 #define DHCPINFORM      8
 564
 565 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 566
 567 static struct packet_type bootp_packet_type __initdata = {
 568         .type = __constant_htons(ETH_P_IP),
 569         .func = ic_bootp_recv,
 570 };
 571
 572
 573 /*
 574  *  Initialize DHCP/BOOTP extension fields in the request.
 575  */
 576
 577 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 578
 579 #ifdef IPCONFIG_DHCP
 580
 581 static void __init
 582 ic_dhcp_init_options(u8 *options)
 583 {
 584         u8 mt = ((ic_servaddr == NONE)
 585                  ? DHCPDISCOVER : DHCPREQUEST);
 586         u8 *e = options;
 587
 588 #ifdef IPCONFIG_DEBUG
 589         printk("DHCP: Sending message type %d\n", mt);
 590 #endif
 591
 592         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 593         e += 4;
 594
 595         *e++ = 53;              /* DHCP message type */
 596         *e++ = 1;
 597         *e++ = mt;
 598
 599         if (mt == DHCPREQUEST) {
 600                 *e++ = 54;      /* Server ID (IP address) */
 601                 *e++ = 4;
 602                 memcpy(e, &ic_servaddr, 4);
 603                 e += 4;
 604
 605                 *e++ = 50;      /* Requested IP address */
 606                 *e++ = 4;
 607                 memcpy(e, &ic_myaddr, 4);
 608                 e += 4;
 609         }
 610
 611         /* always? */
 612         {
 613                 static const u8 ic_req_params[] = {
 614                         1,      /* Subnet mask */
 615                         3,      /* Default gateway */
 616                         6,      /* DNS server */
 617                         12,     /* Host name */
 618                         15,     /* Domain name */
 619                         17,     /* Boot path */
 620                         40,     /* NIS domain name */
 621                 };
 622
 623                 *e++ = 55;      /* Parameter request list */
 624                 *e++ = sizeof(ic_req_params);
 625                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 626                 e += sizeof(ic_req_params);
 627         }
 628
 629         *e++ = 255;     /* End of the list */
 630 }
 631
 632 #endif /* IPCONFIG_DHCP */
 633
 634 static void __init ic_bootp_init_ext(u8 *e)
 635 {
 636         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 637         e += 4;
 638         *e++ = 1;               /* Subnet mask request */
 639         *e++ = 4;
 640         e += 4;
 641         *e++ = 3;               /* Default gateway request */
 642         *e++ = 4;
 643         e += 4;
 644         *e++ = 5;               /* Name server request */
 645         *e++ = 8;
 646         e += 8;
 647         *e++ = 12;              /* Host name request */
 648         *e++ = 32;
 649         e += 32;
 650         *e++ = 40;              /* NIS Domain name request */
 651         *e++ = 32;
 652         e += 32;
 653         *e++ = 17;              /* Boot path */
 654         *e++ = 40;
 655         e += 40;
 656
 657         *e++ = 57;              /* set extension buffer size for reply */
 658         *e++ = 2;
 659         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 660         *e++ = 150;
 661
 662         *e++ = 255;             /* End of the list */
 663 }
 664
 665
 666 /*
 667  *  Initialize the DHCP/BOOTP mechanism.
 668  */
 669 static inline void ic_bootp_init(void)
 670 {
 671         int i;
 672
 673         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 674                 ic_nameservers[i] = NONE;
 675
 676         dev_add_pack(&bootp_packet_type);
 677 }
 678
 679
 680 /*
 681  *  DHCP/BOOTP cleanup.
 682  */
 683 static inline void ic_bootp_cleanup(void)
 684 {
 685         dev_remove_pack(&bootp_packet_type);
 686 }
 687
 688
 689 /*
 690  *  Send DHCP/BOOTP request to single interface.
 691  */
 692 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 693 {
 694         struct net_device *dev = d->dev;
 695         struct sk_buff *skb;
 696         struct bootp_pkt *b;
 697         int hh_len = LL_RESERVED_SPACE(dev);
 698         struct iphdr *h;
 699
 700         /* Allocate packet */
 701         skb = alloc_skb(sizeof(struct bootp_pkt) + hh_len + 15, GFP_KERNEL);
 702         if (!skb)
 703                 return;
 704         skb_reserve(skb, hh_len);
 705         b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
 706         memset(b, 0, sizeof(struct bootp_pkt));
 707
 708         /* Construct IP header */
 709         skb_reset_network_header(skb);
 710         h = ip_hdr(skb);
 711         h->version = 4;
 712         h->ihl = 5;
 713         h->tot_len = htons(sizeof(struct bootp_pkt));
 714         h->frag_off = htons(IP_DF);
 715         h->ttl = 64;
 716         h->protocol = IPPROTO_UDP;
 717         h->daddr = htonl(INADDR_BROADCAST);
 718         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 719
 720         /* Construct UDP header */
 721         b->udph.source = htons(68);
 722         b->udph.dest = htons(67);
 723         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 724         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 725
 726         /* Construct DHCP/BOOTP header */
 727         b->op = BOOTP_REQUEST;
 728         if (dev->type < 256) /* check for false types */
 729                 b->htype = dev->type;
 730         else if (dev->type == ARPHRD_IEEE802_TR) /* fix for token ring */
 731                 b->htype = ARPHRD_IEEE802;
 732         else if (dev->type == ARPHRD_FDDI)
 733                 b->htype = ARPHRD_ETHER;
 734         else {
 735                 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
 736                 b->htype = dev->type; /* can cause undefined behavior */
 737         }
 738         b->hlen = dev->addr_len;
 739         b->your_ip = NONE;
 740         b->server_ip = NONE;
 741         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 742         b->secs = htons(jiffies_diff / HZ);
 743         b->xid = d->xid;
 744
 745         /* add DHCP options or BOOTP extensions */
 746 #ifdef IPCONFIG_DHCP
 747         if (ic_proto_enabled & IC_USE_DHCP)
 748                 ic_dhcp_init_options(b->exten);
 749         else
 750 #endif
 751                 ic_bootp_init_ext(b->exten);
 752
 753         /* Chain packet down the line... */
 754         skb->dev = dev;
 755         skb->protocol = htons(ETH_P_IP);
 756         if ((dev->hard_header &&
 757              dev->hard_header(skb, dev, ntohs(skb->protocol), dev->broadcast, dev->dev_addr, skb->len) < 0) ||
 758             dev_queue_xmit(skb) < 0)
 759                 printk("E");
 760 }
 761
 762
 763 /*
 764  *  Copy BOOTP-supplied string if not already set.
 765  */
 766 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 767 {
 768         if (!len)
 769                 return 0;
 770         if (len > max-1)
 771                 len = max-1;
 772         memcpy(dest, src, len);
 773         dest[len] = '\0';
 774         return 1;
 775 }
 776
 777
 778 /*
 779  *  Process BOOTP extensions.
 780  */
 781 static void __init ic_do_bootp_ext(u8 *ext)
 782 {
 783        u8 servers;
 784        int i;
 785
 786 #ifdef IPCONFIG_DEBUG
 787         u8 *c;
 788
 789         printk("DHCP/BOOTP: Got extension %d:",*ext);
 790         for (c=ext+2; c<ext+2+ext[1]; c++)
 791                 printk(" %02x", *c);
 792         printk("\n");
 793 #endif
 794
 795         switch (*ext++) {
 796                 case 1:         /* Subnet mask */
 797                         if (ic_netmask == NONE)
 798                                 memcpy(&ic_netmask, ext+1, 4);
 799                         break;
 800                 case 3:         /* Default gateway */
 801                         if (ic_gateway == NONE)
 802                                 memcpy(&ic_gateway, ext+1, 4);
 803                         break;
 804                 case 6:         /* DNS server */
 805                         servers= *ext/4;
 806                         if (servers > CONF_NAMESERVERS_MAX)
 807                                 servers = CONF_NAMESERVERS_MAX;
 808                         for (i = 0; i < servers; i++) {
 809                                 if (ic_nameservers[i] == NONE)
 810                                         memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 811                         }
 812                         break;
 813                 case 12:        /* Host name */
 814                         ic_bootp_string(utsname()->nodename, ext+1, *ext, __NEW_UTS_LEN);
 815                         ic_host_name_set = 1;
 816                         break;
 817                 case 15:        /* Domain name (DNS) */
 818                         ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
 819                         break;
 820                 case 17:        /* Root path */
 821                         if (!root_server_path[0])
 822                                 ic_bootp_string(root_server_path, ext+1, *ext, sizeof(root_server_path));
 823                         break;
 824                 case 40:        /* NIS Domain name (_not_ DNS) */
 825                         ic_bootp_string(utsname()->domainname, ext+1, *ext, __NEW_UTS_LEN);
 826                         break;
 827         }
 828 }
 829
 830
 831 /*
 832  *  Receive BOOTP reply.
 833  */
 834 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 835 {
 836         struct bootp_pkt *b;
 837         struct iphdr *h;
 838         struct ic_device *d;
 839         int len, ext_len;
 840
 841         if (dev->nd_net != &init_net)
 842                 goto drop;
 843
 844         /* Perform verifications before taking the lock.  */
 845         if (skb->pkt_type == PACKET_OTHERHOST)
 846                 goto drop;
 847
 848         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 849                 return NET_RX_DROP;
 850
 851         if (!pskb_may_pull(skb,
 852                            sizeof(struct iphdr) +
 853                            sizeof(struct udphdr)))
 854                 goto drop;
 855
 856         b = (struct bootp_pkt *)skb_network_header(skb);
 857         h = &b->iph;
 858
 859         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
 860                 goto drop;
 861
 862         /* Fragments are not supported */
 863         if (h->frag_off & htons(IP_OFFSET | IP_MF)) {
 864                 if (net_ratelimit())
 865                         printk(KERN_ERR "DHCP/BOOTP: Ignoring fragmented "
 866                                "reply.\n");
 867                 goto drop;
 868         }
 869
 870         if (skb->len < ntohs(h->tot_len))
 871                 goto drop;
 872
 873         if (ip_fast_csum((char *) h, h->ihl))
 874                 goto drop;
 875
 876         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
 877                 goto drop;
 878
 879         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
 880                 goto drop;
 881
 882         len = ntohs(b->udph.len) - sizeof(struct udphdr);
 883         ext_len = len - (sizeof(*b) -
 884                          sizeof(struct iphdr) -
 885                          sizeof(struct udphdr) -
 886                          sizeof(b->exten));
 887         if (ext_len < 0)
 888                 goto drop;
 889
 890         /* Ok the front looks good, make sure we can get at the rest.  */
 891         if (!pskb_may_pull(skb, skb->len))
 892                 goto drop;
 893
 894         b = (struct bootp_pkt *)skb_network_header(skb);
 895         h = &b->iph;
 896
 897         /* One reply at a time, please. */
 898         spin_lock(&ic_recv_lock);
 899
 900         /* If we already have a reply, just drop the packet */
 901         if (ic_got_reply)
 902                 goto drop_unlock;
 903
 904         /* Find the ic_device that the packet arrived on */
 905         d = ic_first_dev;
 906         while (d && d->dev != dev)
 907                 d = d->next;
 908         if (!d)
 909                 goto drop_unlock;  /* should never happen */
 910
 911         /* Is it a reply to our BOOTP request? */
 912         if (b->op != BOOTP_REPLY ||
 913             b->xid != d->xid) {
 914                 if (net_ratelimit())
 915                         printk(KERN_ERR "DHCP/BOOTP: Reply not for us, "
 916                                "op[%x] xid[%x]\n",
 917                                b->op, b->xid);
 918                 goto drop_unlock;
 919         }
 920
 921         /* Parse extensions */
 922         if (ext_len >= 4 &&
 923             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
 924                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
 925                 u8 *ext;
 926
 927 #ifdef IPCONFIG_DHCP
 928                 if (ic_proto_enabled & IC_USE_DHCP) {
 929                         __be32 server_id = NONE;
 930                         int mt = 0;
 931
 932                         ext = &b->exten[4];
 933                         while (ext < end && *ext != 0xff) {
 934                                 u8 *opt = ext++;
 935                                 if (*opt == 0)  /* Padding */
 936                                         continue;
 937                                 ext += *ext + 1;
 938                                 if (ext >= end)
 939                                         break;
 940                                 switch (*opt) {
 941                                 case 53:        /* Message type */
 942                                         if (opt[1])
 943                                                 mt = opt[2];
 944                                         break;
 945                                 case 54:        /* Server ID (IP address) */
 946                                         if (opt[1] >= 4)
 947                                                 memcpy(&server_id, opt + 2, 4);
 948                                         break;
 949                                 }
 950                         }
 951
 952 #ifdef IPCONFIG_DEBUG
 953                         printk("DHCP: Got message type %d\n", mt);
 954 #endif
 955
 956                         switch (mt) {
 957                         case DHCPOFFER:
 958                                 /* While in the process of accepting one offer,
 959                                  * ignore all others.
 960                                  */
 961                                 if (ic_myaddr != NONE)
 962                                         goto drop_unlock;
 963
 964                                 /* Let's accept that offer. */
 965                                 ic_myaddr = b->your_ip;
 966                                 ic_servaddr = server_id;
 967 #ifdef IPCONFIG_DEBUG
 968                                 printk("DHCP: Offered address %u.%u.%u.%u",
 969                                        NIPQUAD(ic_myaddr));
 970                                 printk(" by server %u.%u.%u.%u\n",
 971                                        NIPQUAD(ic_servaddr));
 972 #endif
 973                                 /* The DHCP indicated server address takes
 974                                  * precedence over the bootp header one if
 975                                  * they are different.
 976                                  */
 977                                 if ((server_id != NONE) &&
 978                                     (b->server_ip != server_id))
 979                                         b->server_ip = ic_servaddr;
 980                                 break;
 981
 982                         case DHCPACK:
 983                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
 984                                         goto drop_unlock;
 985
 986                                 /* Yeah! */
 987                                 break;
 988
 989                         default:
 990                                 /* Urque.  Forget it*/
 991                                 ic_myaddr = NONE;
 992                                 ic_servaddr = NONE;
 993                                 goto drop_unlock;
 994                         }
 995
 996                         ic_dhcp_msgtype = mt;
 997
 998                 }
 999 #endif /* IPCONFIG_DHCP */
1000
1001                 ext = &b->exten[4];
1002                 while (ext < end && *ext != 0xff) {
1003                         u8 *opt = ext++;
1004                         if (*opt == 0)  /* Padding */
1005                                 continue;
1006                         ext += *ext + 1;
1007                         if (ext < end)
1008                                 ic_do_bootp_ext(opt);
1009                 }
1010         }
1011
1012         /* We have a winner! */
1013         ic_dev = dev;
1014         ic_myaddr = b->your_ip;
1015         ic_servaddr = b->server_ip;
1016         if (ic_gateway == NONE && b->relay_ip)
1017                 ic_gateway = b->relay_ip;
1018         if (ic_nameservers[0] == NONE)
1019                 ic_nameservers[0] = ic_servaddr;
1020         ic_got_reply = IC_BOOTP;
1021
1022 drop_unlock:
1023         /* Show's over.  Nothing to see here.  */
1024         spin_unlock(&ic_recv_lock);
1025
1026 drop:
1027         /* Throw the packet out. */
1028         kfree_skb(skb);
1029
1030         return 0;
1031 }
1032
1033
1034 #endif
1035
1036
1037 /*
1038  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1039  */
1040
1041 #ifdef IPCONFIG_DYNAMIC
1042
1043 static int __init ic_dynamic(void)
1044 {
1045         int retries;
1046         struct ic_device *d;
1047         unsigned long start_jiffies, timeout, jiff;
1048         int do_bootp = ic_proto_have_if & IC_BOOTP;
1049         int do_rarp = ic_proto_have_if & IC_RARP;
1050
1051         /*
1052          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1053          * This routine gets only called when some pieces of information
1054          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1055          */
1056         if (!ic_proto_enabled) {
1057                 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1058                 return -1;
1059         }
1060
1061 #ifdef IPCONFIG_BOOTP
1062         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1063                 printk(KERN_ERR "DHCP/BOOTP: No suitable device found.\n");
1064 #endif
1065 #ifdef IPCONFIG_RARP
1066         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1067                 printk(KERN_ERR "RARP: No suitable device found.\n");
1068 #endif
1069
1070         if (!ic_proto_have_if)
1071                 /* Error message already printed */
1072                 return -1;
1073
1074         /*
1075          * Setup protocols
1076          */
1077 #ifdef IPCONFIG_BOOTP
1078         if (do_bootp)
1079                 ic_bootp_init();
1080 #endif
1081 #ifdef IPCONFIG_RARP
1082         if (do_rarp)
1083                 ic_rarp_init();
1084 #endif
1085
1086         /*
1087          * Send requests and wait, until we get an answer. This loop
1088          * seems to be a terrible waste of CPU time, but actually there is
1089          * only one process running at all, so we don't need to use any
1090          * scheduler functions.
1091          * [Actually we could now, but the nothing else running note still
1092          *  applies.. - AC]
1093          */
1094         printk(KERN_NOTICE "Sending %s%s%s requests .",
1095                do_bootp
1096                 ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1097                (do_bootp && do_rarp) ? " and " : "",
1098                do_rarp ? "RARP" : "");
1099
1100         start_jiffies = jiffies;
1101         d = ic_first_dev;
1102         retries = CONF_SEND_RETRIES;
1103         get_random_bytes(&timeout, sizeof(timeout));
1104         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM);
1105         for (;;) {
1106 #ifdef IPCONFIG_BOOTP
1107                 if (do_bootp && (d->able & IC_BOOTP))
1108                         ic_bootp_send_if(d, jiffies - start_jiffies);
1109 #endif
1110 #ifdef IPCONFIG_RARP
1111                 if (do_rarp && (d->able & IC_RARP))
1112                         ic_rarp_send_if(d);
1113 #endif
1114
1115                 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1116                 while (time_before(jiffies, jiff) && !ic_got_reply)
1117                         schedule_timeout_uninterruptible(1);
1118 #ifdef IPCONFIG_DHCP
1119                 /* DHCP isn't done until we get a DHCPACK. */
1120                 if ((ic_got_reply & IC_BOOTP)
1121                     && (ic_proto_enabled & IC_USE_DHCP)
1122                     && ic_dhcp_msgtype != DHCPACK)
1123                 {
1124                         ic_got_reply = 0;
1125                         printk(",");
1126                         continue;
1127                 }
1128 #endif /* IPCONFIG_DHCP */
1129
1130                 if (ic_got_reply) {
1131                         printk(" OK\n");
1132                         break;
1133                 }
1134
1135                 if ((d = d->next))
1136                         continue;
1137
1138                 if (! --retries) {
1139                         printk(" timed out!\n");
1140                         break;
1141                 }
1142
1143                 d = ic_first_dev;
1144
1145                 timeout = timeout CONF_TIMEOUT_MULT;
1146                 if (timeout > CONF_TIMEOUT_MAX)
1147                         timeout = CONF_TIMEOUT_MAX;
1148
1149                 printk(".");
1150         }
1151
1152 #ifdef IPCONFIG_BOOTP
1153         if (do_bootp)
1154                 ic_bootp_cleanup();
1155 #endif
1156 #ifdef IPCONFIG_RARP
1157         if (do_rarp)
1158                 ic_rarp_cleanup();
1159 #endif
1160
1161         if (!ic_got_reply) {
1162                 ic_myaddr = NONE;
1163                 return -1;
1164         }
1165
1166         printk("IP-Config: Got %s answer from %u.%u.%u.%u, ",
1167                 ((ic_got_reply & IC_RARP) ? "RARP"
1168                  : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1169                 NIPQUAD(ic_servaddr));
1170         printk("my address is %u.%u.%u.%u\n", NIPQUAD(ic_myaddr));
1171
1172         return 0;
1173 }
1174
1175 #endif /* IPCONFIG_DYNAMIC */
1176
1177 #ifdef CONFIG_PROC_FS
1178
1179 static int pnp_seq_show(struct seq_file *seq, void *v)
1180 {
1181         int i;
1182
1183         if (ic_proto_used & IC_PROTO)
1184                 seq_printf(seq, "#PROTO: %s\n",
1185                            (ic_proto_used & IC_RARP) ? "RARP"
1186                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1187         else
1188                 seq_puts(seq, "#MANUAL\n");
1189
1190         if (ic_domain[0])
1191                 seq_printf(seq,
1192                            "domain %s\n", ic_domain);
1193         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1194                 if (ic_nameservers[i] != NONE)
1195                         seq_printf(seq,
1196                                    "nameserver %u.%u.%u.%u\n",
1197                                    NIPQUAD(ic_nameservers[i]));
1198         }
1199         if (ic_servaddr != NONE)
1200                 seq_printf(seq,
1201                            "bootserver %u.%u.%u.%u\n",
1202                            NIPQUAD(ic_servaddr));
1203         return 0;
1204 }
1205
1206 static int pnp_seq_open(struct inode *indoe, struct file *file)
1207 {
1208         return single_open(file, pnp_seq_show, NULL);
1209 }
1210
1211 static const struct file_operations pnp_seq_fops = {
1212         .owner          = THIS_MODULE,
1213         .open           = pnp_seq_open,
1214         .read           = seq_read,
1215         .llseek         = seq_lseek,
1216         .release        = single_release,
1217 };
1218 #endif /* CONFIG_PROC_FS */
1219
1220 /*
1221  *  Extract IP address from the parameter string if needed. Note that we
1222  *  need to have root_server_addr set _before_ IPConfig gets called as it
1223  *  can override it.
1224  */
1225 __be32 __init root_nfs_parse_addr(char *name)
1226 {
1227         __be32 addr;
1228         int octets = 0;
1229         char *cp, *cq;
1230
1231         cp = cq = name;
1232         while (octets < 4) {
1233                 while (*cp >= '0' && *cp <= '9')
1234                         cp++;
1235                 if (cp == cq || cp - cq > 3)
1236                         break;
1237                 if (*cp == '.' || octets == 3)
1238                         octets++;
1239                 if (octets < 4)
1240                         cp++;
1241                 cq = cp;
1242         }
1243         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1244                 if (*cp == ':')
1245                         *cp++ = '\0';
1246                 addr = in_aton(name);
1247                 memmove(name, cp, strlen(cp) + 1);
1248         } else
1249                 addr = NONE;
1250
1251         return addr;
1252 }
1253
1254 /*
1255  *      IP Autoconfig dispatcher.
1256  */
1257
1258 static int __init ip_auto_config(void)
1259 {
1260         __be32 addr;
1261
1262 #ifdef CONFIG_PROC_FS
1263         proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1264 #endif /* CONFIG_PROC_FS */
1265
1266         if (!ic_enable)
1267                 return 0;
1268
1269         DBG(("IP-Config: Entered.\n"));
1270 #ifdef IPCONFIG_DYNAMIC
1271  try_try_again:
1272 #endif
1273         /* Give hardware a chance to settle */
1274         msleep(CONF_PRE_OPEN);
1275
1276         /* Setup all network devices */
1277         if (ic_open_devs() < 0)
1278                 return -1;
1279
1280         /* Give drivers a chance to settle */
1281         ssleep(CONF_POST_OPEN);
1282
1283         /*
1284          * If the config information is insufficient (e.g., our IP address or
1285          * IP address of the boot server is missing or we have multiple network
1286          * interfaces and no default was set), use BOOTP or RARP to get the
1287          * missing values.
1288          */
1289         if (ic_myaddr == NONE ||
1290 #ifdef CONFIG_ROOT_NFS
1291             (root_server_addr == NONE
1292              && ic_servaddr == NONE
1293              && ROOT_DEV == Root_NFS) ||
1294 #endif
1295             ic_first_dev->next) {
1296 #ifdef IPCONFIG_DYNAMIC
1297
1298                 int retries = CONF_OPEN_RETRIES;
1299
1300                 if (ic_dynamic() < 0) {
1301                         ic_close_devs();
1302
1303                         /*
1304                          * I don't know why, but sometimes the
1305                          * eepro100 driver (at least) gets upset and
1306                          * doesn't work the first time it's opened.
1307                          * But then if you close it and reopen it, it
1308                          * works just fine.  So we need to try that at
1309                          * least once before giving up.
1310                          *
1311                          * Also, if the root will be NFS-mounted, we
1312                          * have nowhere to go if DHCP fails.  So we
1313                          * just have to keep trying forever.
1314                          *
1315                          *                              -- Chip
1316                          */
1317 #ifdef CONFIG_ROOT_NFS
1318                         if (ROOT_DEV ==  Root_NFS) {
1319                                 printk(KERN_ERR
1320                                         "IP-Config: Retrying forever (NFS root)...\n");
1321                                 goto try_try_again;
1322                         }
1323 #endif
1324
1325                         if (--retries) {
1326                                 printk(KERN_ERR
1327                                        "IP-Config: Reopening network devices...\n");
1328                                 goto try_try_again;
1329                         }
1330
1331                         /* Oh, well.  At least we tried. */
1332                         printk(KERN_ERR "IP-Config: Auto-configuration of network failed.\n");
1333                         return -1;
1334                 }
1335 #else /* !DYNAMIC */
1336                 printk(KERN_ERR "IP-Config: Incomplete network configuration information.\n");
1337                 ic_close_devs();
1338                 return -1;
1339 #endif /* IPCONFIG_DYNAMIC */
1340         } else {
1341                 /* Device selected manually or only one device -> use it */
1342                 ic_dev = ic_first_dev->dev;
1343         }
1344
1345         addr = root_nfs_parse_addr(root_server_path);
1346         if (root_server_addr == NONE)
1347                 root_server_addr = addr;
1348
1349         /*
1350          * Use defaults whereever applicable.
1351          */
1352         if (ic_defaults() < 0)
1353                 return -1;
1354
1355         /*
1356          * Close all network devices except the device we've
1357          * autoconfigured and set up routes.
1358          */
1359         ic_close_devs();
1360         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1361                 return -1;
1362
1363         /*
1364          * Record which protocol was actually used.
1365          */
1366 #ifdef IPCONFIG_DYNAMIC
1367         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1368 #endif
1369
1370 #ifndef IPCONFIG_SILENT
1371         /*
1372          * Clue in the operator.
1373          */
1374         printk("IP-Config: Complete:");
1375         printk("\n      device=%s", ic_dev->name);
1376         printk(", addr=%u.%u.%u.%u", NIPQUAD(ic_myaddr));
1377         printk(", mask=%u.%u.%u.%u", NIPQUAD(ic_netmask));
1378         printk(", gw=%u.%u.%u.%u", NIPQUAD(ic_gateway));
1379         printk(",\n     host=%s, domain=%s, nis-domain=%s",
1380                utsname()->nodename, ic_domain, utsname()->domainname);
1381         printk(",\n     bootserver=%u.%u.%u.%u", NIPQUAD(ic_servaddr));
1382         printk(", rootserver=%u.%u.%u.%u", NIPQUAD(root_server_addr));
1383         printk(", rootpath=%s", root_server_path);
1384         printk("\n");
1385 #endif /* !SILENT */
1386
1387         return 0;
1388 }
1389
1390 late_initcall(ip_auto_config);
1391
1392
1393 /*
1394  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1395  *  command line parameter. It consists of option fields separated by colons in
1396  *  the following order:
1397  *
1398  *  <client-ip>:<server-ip>:<gw-ip>:<netmask>:<host name>:<device>:<PROTO>
1399  *
1400  *  Any of the fields can be empty which means to use a default value:
1401  *      <client-ip>     - address given by BOOTP or RARP
1402  *      <server-ip>     - address of host returning BOOTP or RARP packet
1403  *      <gw-ip>         - none, or the address returned by BOOTP
1404  *      <netmask>       - automatically determined from <client-ip>, or the
1405  *                        one returned by BOOTP
1406  *      <host name>     - <client-ip> in ASCII notation, or the name returned
1407  *                        by BOOTP
1408  *      <device>        - use all available devices
1409  *      <PROTO>:
1410  *         off|none         - don't do autoconfig at all (DEFAULT)
1411  *         on|any           - use any configured protocol
1412  *         dhcp|bootp|rarp  - use only the specified protocol
1413  *         both             - use both BOOTP and RARP (not DHCP)
1414  */
1415 static int __init ic_proto_name(char *name)
1416 {
1417         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1418                 return 1;
1419         }
1420 #ifdef CONFIG_IP_PNP_DHCP
1421         else if (!strcmp(name, "dhcp")) {
1422                 ic_proto_enabled &= ~IC_RARP;
1423                 return 1;
1424         }
1425 #endif
1426 #ifdef CONFIG_IP_PNP_BOOTP
1427         else if (!strcmp(name, "bootp")) {
1428                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1429                 return 1;
1430         }
1431 #endif
1432 #ifdef CONFIG_IP_PNP_RARP
1433         else if (!strcmp(name, "rarp")) {
1434                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1435                 return 1;
1436         }
1437 #endif
1438 #ifdef IPCONFIG_DYNAMIC
1439         else if (!strcmp(name, "both")) {
1440                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1441                 return 1;
1442         }
1443 #endif
1444         return 0;
1445 }
1446
1447 static int __init ip_auto_config_setup(char *addrs)
1448 {
1449         char *cp, *ip, *dp;
1450         int num = 0;
1451
1452         ic_set_manually = 1;
1453
1454         ic_enable = (*addrs &&
1455                 (strcmp(addrs, "off") != 0) &&
1456                 (strcmp(addrs, "none") != 0));
1457         if (!ic_enable)
1458                 return 1;
1459
1460         if (ic_proto_name(addrs))
1461                 return 1;
1462
1463         /* Parse the whole string */
1464         ip = addrs;
1465         while (ip && *ip) {
1466                 if ((cp = strchr(ip, ':')))
1467                         *cp++ = '\0';
1468                 if (strlen(ip) > 0) {
1469                         DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1470                         switch (num) {
1471                         case 0:
1472                                 if ((ic_myaddr = in_aton(ip)) == INADDR_ANY)
1473                                         ic_myaddr = NONE;
1474                                 break;
1475                         case 1:
1476                                 if ((ic_servaddr = in_aton(ip)) == INADDR_ANY)
1477                                         ic_servaddr = NONE;
1478                                 break;
1479                         case 2:
1480                                 if ((ic_gateway = in_aton(ip)) == INADDR_ANY)
1481                                         ic_gateway = NONE;
1482                                 break;
1483                         case 3:
1484                                 if ((ic_netmask = in_aton(ip)) == INADDR_ANY)
1485                                         ic_netmask = NONE;
1486                                 break;
1487                         case 4:
1488                                 if ((dp = strchr(ip, '.'))) {
1489                                         *dp++ = '\0';
1490                                         strlcpy(utsname()->domainname, dp,
1491                                                 sizeof(utsname()->domainname));
1492                                 }
1493                                 strlcpy(utsname()->nodename, ip,
1494                                         sizeof(utsname()->nodename));
1495                                 ic_host_name_set = 1;
1496                                 break;
1497                         case 5:
1498                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1499                                 break;
1500                         case 6:
1501                                 ic_proto_name(ip);
1502                                 break;
1503                         }
1504                 }
1505                 ip = cp;
1506                 num++;
1507         }
1508
1509         return 1;
1510 }
1511
1512 static int __init nfsaddrs_config_setup(char *addrs)
1513 {
1514         return ip_auto_config_setup(addrs);
1515 }
1516
1517 __setup("ip=", ip_auto_config_setup);
1518 __setup("nfsaddrs=", nfsaddrs_config_setup);