net/ipv4/ipconfig.c

   1 /*
   2  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
   3  *  user-supplied information to configure own IP address and routes.
   4  *
   5  *  Copyright (C) 1996-1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
   6  *
   7  *  Derived from network configuration code in fs/nfs/nfsroot.c,
   8  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
   9  *
  10  *  BOOTP rewritten to construct and analyse packets itself instead
  11  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
  12  *                                           -- MJ, December 1998
  13  *
  14  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
  15  *  initialization scheme.
  16  *      - Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 08/11/1999
  17  *
  18  *  DHCP support added.  To users this looks like a whole separate
  19  *  protocol, but we know it's just a bag on the side of BOOTP.
  20  *              -- Chip Salzenberg <chip@valinux.com>, May 2000
  21  *
  22  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
  23  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
  24  *
  25  *  Merged changes from 2.2.19 into 2.4.3
  26  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
  27  *
  28  *  Multiple Nameservers in /proc/net/pnp
  29  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
  30  */
  31
  32 #include <linux/types.h>
  33 #include <linux/string.h>
  34 #include <linux/kernel.h>
  35 #include <linux/jiffies.h>
  36 #include <linux/random.h>
  37 #include <linux/init.h>
  38 #include <linux/utsname.h>
  39 #include <linux/in.h>
  40 #include <linux/if.h>
  41 #include <linux/inet.h>
  42 #include <linux/inetdevice.h>
  43 #include <linux/netdevice.h>
  44 #include <linux/if_arp.h>
  45 #include <linux/skbuff.h>
  46 #include <linux/ip.h>
  47 #include <linux/socket.h>
  48 #include <linux/route.h>
  49 #include <linux/udp.h>
  50 #include <linux/proc_fs.h>
  51 #include <linux/seq_file.h>
  52 #include <linux/major.h>
  53 #include <linux/root_dev.h>
  54 #include <linux/delay.h>
  55 #include <linux/nfs_fs.h>
  56 #include <linux/slab.h>
  57 #include <linux/export.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_POST_OPEN          10      /* After opening: 10 msecs */
  92 #define CONF_CARRIER_TIMEOUT    120000  /* Wait for carrier timeout */
  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 cpu_to_be32(INADDR_NONE)
 106 #define ANY cpu_to_be32(INADDR_ANY)
 107
 108 /*
 109  * Public IP configuration
 110  */
 111
 112 /* This is used by platforms which might be able to set the ipconfig
 113  * variables using firmware environment vars.  If this is set, it will
 114  * ignore such firmware variables.
 115  */
 116 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
 117
 118 static int ic_enable __initdata = 0;            /* IP config enabled? */
 119
 120 /* Protocol choice */
 121 int ic_proto_enabled __initdata = 0
 122 #ifdef IPCONFIG_BOOTP
 123                         | IC_BOOTP
 124 #endif
 125 #ifdef CONFIG_IP_PNP_DHCP
 126                         | IC_USE_DHCP
 127 #endif
 128 #ifdef IPCONFIG_RARP
 129                         | IC_RARP
 130 #endif
 131                         ;
 132
 133 static int ic_host_name_set __initdata = 0;     /* Host name set by us? */
 134
 135 __be32 ic_myaddr = NONE;                /* My IP address */
 136 static __be32 ic_netmask = NONE;        /* Netmask for local subnet */
 137 __be32 ic_gateway = NONE;       /* Gateway IP address */
 138
 139 __be32 ic_servaddr = NONE;      /* Boot server IP address */
 140
 141 __be32 root_server_addr = NONE; /* Address of NFS server */
 142 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
 143
 144 __be32 ic_dev_xid;              /* Device under configuration */
 145
 146 /* vendor class identifier */
 147 static char vendor_class_identifier[253] __initdata;
 148
 149 /* Persistent data: */
 150
 151 static int ic_proto_used;                       /* Protocol used, if any */
 152 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
 153 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
 154
 155 /*
 156  * Private state.
 157  */
 158
 159 /* Name of user-selected boot device */
 160 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 161
 162 /* Protocols supported by available interfaces */
 163 static int ic_proto_have_if __initdata = 0;
 164
 165 /* MTU for boot device */
 166 static int ic_dev_mtu __initdata = 0;
 167
 168 #ifdef IPCONFIG_DYNAMIC
 169 static DEFINE_SPINLOCK(ic_recv_lock);
 170 static volatile int ic_got_reply __initdata = 0;    /* Proto(s) that replied */
 171 #endif
 172 #ifdef IPCONFIG_DHCP
 173 static int ic_dhcp_msgtype __initdata = 0;      /* DHCP msg type received */
 174 #endif
 175
 176
 177 /*
 178  *      Network devices
 179  */
 180
 181 struct ic_device {
 182         struct ic_device *next;
 183         struct net_device *dev;
 184         unsigned short flags;
 185         short able;
 186         __be32 xid;
 187 };
 188
 189 static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
 190 static struct net_device *ic_dev __initdata = NULL;     /* Selected device */
 191
 192 static bool __init ic_is_init_dev(struct net_device *dev)
 193 {
 194         if (dev->flags & IFF_LOOPBACK)
 195                 return false;
 196         return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 197             (!(dev->flags & IFF_LOOPBACK) &&
 198              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 199              strncmp(dev->name, "dummy", 5));
 200 }
 201
 202 static int __init ic_open_devs(void)
 203 {
 204         struct ic_device *d, **last;
 205         struct net_device *dev;
 206         unsigned short oflags;
 207         unsigned long start;
 208
 209         last = &ic_first_dev;
 210         rtnl_lock();
 211
 212         /* bring loopback device up first */
 213         for_each_netdev(&init_net, dev) {
 214                 if (!(dev->flags & IFF_LOOPBACK))
 215                         continue;
 216                 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
 217                         pr_err("IP-Config: Failed to open %s\n", dev->name);
 218         }
 219
 220         for_each_netdev(&init_net, dev) {
 221                 if (ic_is_init_dev(dev)) {
 222                         int able = 0;
 223                         if (dev->mtu >= 364)
 224                                 able |= IC_BOOTP;
 225                         else
 226                                 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small",
 227                                         dev->name, dev->mtu);
 228                         if (!(dev->flags & IFF_NOARP))
 229                                 able |= IC_RARP;
 230                         able &= ic_proto_enabled;
 231                         if (ic_proto_enabled && !able)
 232                                 continue;
 233                         oflags = dev->flags;
 234                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
 235                                 pr_err("IP-Config: Failed to open %s\n",
 236                                        dev->name);
 237                                 continue;
 238                         }
 239                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 240                                 rtnl_unlock();
 241                                 return -ENOMEM;
 242                         }
 243                         d->dev = dev;
 244                         *last = d;
 245                         last = &d->next;
 246                         d->flags = oflags;
 247                         d->able = able;
 248                         if (able & IC_BOOTP)
 249                                 get_random_bytes(&d->xid, sizeof(__be32));
 250                         else
 251                                 d->xid = 0;
 252                         ic_proto_have_if |= able;
 253                         DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
 254                                 dev->name, able, d->xid));
 255                 }
 256         }
 257
 258         /* no point in waiting if we could not bring up at least one device */
 259         if (!ic_first_dev)
 260                 goto have_carrier;
 261
 262         /* wait for a carrier on at least one device */
 263         start = jiffies;
 264         while (jiffies - start < msecs_to_jiffies(CONF_CARRIER_TIMEOUT)) {
 265                 for_each_netdev(&init_net, dev)
 266                         if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
 267                                 goto have_carrier;
 268
 269                 msleep(1);
 270         }
 271 have_carrier:
 272         rtnl_unlock();
 273
 274         *last = NULL;
 275
 276         if (!ic_first_dev) {
 277                 if (user_dev_name[0])
 278                         pr_err("IP-Config: Device `%s' not found\n",
 279                                user_dev_name);
 280                 else
 281                         pr_err("IP-Config: No network devices available\n");
 282                 return -ENODEV;
 283         }
 284         return 0;
 285 }
 286
 287 static void __init ic_close_devs(void)
 288 {
 289         struct ic_device *d, *next;
 290         struct net_device *dev;
 291
 292         rtnl_lock();
 293         next = ic_first_dev;
 294         while ((d = next)) {
 295                 next = d->next;
 296                 dev = d->dev;
 297                 if (dev != ic_dev) {
 298                         DBG(("IP-Config: Downing %s\n", dev->name));
 299                         dev_change_flags(dev, d->flags);
 300                 }
 301                 kfree(d);
 302         }
 303         rtnl_unlock();
 304 }
 305
 306 /*
 307  *      Interface to various network functions.
 308  */
 309
 310 static inline void
 311 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
 312 {
 313         sin->sin_family = AF_INET;
 314         sin->sin_addr.s_addr = addr;
 315         sin->sin_port = port;
 316 }
 317
 318 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
 319 {
 320         int res;
 321
 322         mm_segment_t oldfs = get_fs();
 323         set_fs(get_ds());
 324         res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
 325         set_fs(oldfs);
 326         return res;
 327 }
 328
 329 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
 330 {
 331         int res;
 332
 333         mm_segment_t oldfs = get_fs();
 334         set_fs(get_ds());
 335         res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
 336         set_fs(oldfs);
 337         return res;
 338 }
 339
 340 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
 341 {
 342         int res;
 343
 344         mm_segment_t oldfs = get_fs();
 345         set_fs(get_ds());
 346         res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
 347         set_fs(oldfs);
 348         return res;
 349 }
 350
 351 /*
 352  *      Set up interface addresses and routes.
 353  */
 354
 355 static int __init ic_setup_if(void)
 356 {
 357         struct ifreq ir;
 358         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 359         int err;
 360
 361         memset(&ir, 0, sizeof(ir));
 362         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
 363         set_sockaddr(sin, ic_myaddr, 0);
 364         if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
 365                 pr_err("IP-Config: Unable to set interface address (%d)\n",
 366                        err);
 367                 return -1;
 368         }
 369         set_sockaddr(sin, ic_netmask, 0);
 370         if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
 371                 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
 372                        err);
 373                 return -1;
 374         }
 375         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 376         if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
 377                 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
 378                        err);
 379                 return -1;
 380         }
 381         /* Handle the case where we need non-standard MTU on the boot link (a network
 382          * using jumbo frames, for instance).  If we can't set the mtu, don't error
 383          * out, we'll try to muddle along.
 384          */
 385         if (ic_dev_mtu != 0) {
 386                 strcpy(ir.ifr_name, ic_dev->name);
 387                 ir.ifr_mtu = ic_dev_mtu;
 388                 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
 389                         pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
 390                                ic_dev_mtu, err);
 391         }
 392         return 0;
 393 }
 394
 395 static int __init ic_setup_routes(void)
 396 {
 397         /* No need to setup device routes, only the default route... */
 398
 399         if (ic_gateway != NONE) {
 400                 struct rtentry rm;
 401                 int err;
 402
 403                 memset(&rm, 0, sizeof(rm));
 404                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 405                         pr_err("IP-Config: Gateway not on directly connected network\n");
 406                         return -1;
 407                 }
 408                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 409                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 410                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 411                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 412                 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
 413                         pr_err("IP-Config: Cannot add default route (%d)\n",
 414                                err);
 415                         return -1;
 416                 }
 417         }
 418
 419         return 0;
 420 }
 421
 422 /*
 423  *      Fill in default values for all missing parameters.
 424  */
 425
 426 static int __init ic_defaults(void)
 427 {
 428         /*
 429          *      At this point we have no userspace running so need not
 430          *      claim locks on system_utsname
 431          */
 432
 433         if (!ic_host_name_set)
 434                 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
 435
 436         if (root_server_addr == NONE)
 437                 root_server_addr = ic_servaddr;
 438
 439         if (ic_netmask == NONE) {
 440                 if (IN_CLASSA(ntohl(ic_myaddr)))
 441                         ic_netmask = htonl(IN_CLASSA_NET);
 442                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 443                         ic_netmask = htonl(IN_CLASSB_NET);
 444                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 445                         ic_netmask = htonl(IN_CLASSC_NET);
 446                 else {
 447                         pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
 448                                &ic_myaddr);
 449                         return -1;
 450                 }
 451                 printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
 452         }
 453
 454         return 0;
 455 }
 456
 457 /*
 458  *      RARP support.
 459  */
 460
 461 #ifdef IPCONFIG_RARP
 462
 463 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 464
 465 static struct packet_type rarp_packet_type __initdata = {
 466         .type = cpu_to_be16(ETH_P_RARP),
 467         .func = ic_rarp_recv,
 468 };
 469
 470 static inline void __init ic_rarp_init(void)
 471 {
 472         dev_add_pack(&rarp_packet_type);
 473 }
 474
 475 static inline void __init ic_rarp_cleanup(void)
 476 {
 477         dev_remove_pack(&rarp_packet_type);
 478 }
 479
 480 /*
 481  *  Process received RARP packet.
 482  */
 483 static int __init
 484 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 485 {
 486         struct arphdr *rarp;
 487         unsigned char *rarp_ptr;
 488         __be32 sip, tip;
 489         unsigned char *sha, *tha;               /* s for "source", t for "target" */
 490         struct ic_device *d;
 491
 492         if (!net_eq(dev_net(dev), &init_net))
 493                 goto drop;
 494
 495         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 496                 return NET_RX_DROP;
 497
 498         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 499                 goto drop;
 500
 501         /* Basic sanity checks can be done without the lock.  */
 502         rarp = (struct arphdr *)skb_transport_header(skb);
 503
 504         /* If this test doesn't pass, it's not IP, or we should
 505          * ignore it anyway.
 506          */
 507         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 508                 goto drop;
 509
 510         /* If it's not a RARP reply, delete it. */
 511         if (rarp->ar_op != htons(ARPOP_RREPLY))
 512                 goto drop;
 513
 514         /* If it's not Ethernet, delete it. */
 515         if (rarp->ar_pro != htons(ETH_P_IP))
 516                 goto drop;
 517
 518         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
 519                 goto drop;
 520
 521         /* OK, it is all there and looks valid, process... */
 522         rarp = (struct arphdr *)skb_transport_header(skb);
 523         rarp_ptr = (unsigned char *) (rarp + 1);
 524
 525         /* One reply at a time, please. */
 526         spin_lock(&ic_recv_lock);
 527
 528         /* If we already have a reply, just drop the packet */
 529         if (ic_got_reply)
 530                 goto drop_unlock;
 531
 532         /* Find the ic_device that the packet arrived on */
 533         d = ic_first_dev;
 534         while (d && d->dev != dev)
 535                 d = d->next;
 536         if (!d)
 537                 goto drop_unlock;       /* should never happen */
 538
 539         /* Extract variable-width fields */
 540         sha = rarp_ptr;
 541         rarp_ptr += dev->addr_len;
 542         memcpy(&sip, rarp_ptr, 4);
 543         rarp_ptr += 4;
 544         tha = rarp_ptr;
 545         rarp_ptr += dev->addr_len;
 546         memcpy(&tip, rarp_ptr, 4);
 547
 548         /* Discard packets which are not meant for us. */
 549         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 550                 goto drop_unlock;
 551
 552         /* Discard packets which are not from specified server. */
 553         if (ic_servaddr != NONE && ic_servaddr != sip)
 554                 goto drop_unlock;
 555
 556         /* We have a winner! */
 557         ic_dev = dev;
 558         if (ic_myaddr == NONE)
 559                 ic_myaddr = tip;
 560         ic_servaddr = sip;
 561         ic_got_reply = IC_RARP;
 562
 563 drop_unlock:
 564         /* Show's over.  Nothing to see here.  */
 565         spin_unlock(&ic_recv_lock);
 566
 567 drop:
 568         /* Throw the packet out. */
 569         kfree_skb(skb);
 570         return 0;
 571 }
 572
 573
 574 /*
 575  *  Send RARP request packet over a single interface.
 576  */
 577 static void __init ic_rarp_send_if(struct ic_device *d)
 578 {
 579         struct net_device *dev = d->dev;
 580         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 581                  dev->dev_addr, dev->dev_addr);
 582 }
 583 #endif
 584
 585 /*
 586  *      DHCP/BOOTP support.
 587  */
 588
 589 #ifdef IPCONFIG_BOOTP
 590
 591 struct bootp_pkt {              /* BOOTP packet format */
 592         struct iphdr iph;       /* IP header */
 593         struct udphdr udph;     /* UDP header */
 594         u8 op;                  /* 1=request, 2=reply */
 595         u8 htype;               /* HW address type */
 596         u8 hlen;                /* HW address length */
 597         u8 hops;                /* Used only by gateways */
 598         __be32 xid;             /* Transaction ID */
 599         __be16 secs;            /* Seconds since we started */
 600         __be16 flags;           /* Just what it says */
 601         __be32 client_ip;               /* Client's IP address if known */
 602         __be32 your_ip;         /* Assigned IP address */
 603         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
 604         __be32 relay_ip;                /* IP address of BOOTP relay */
 605         u8 hw_addr[16];         /* Client's HW address */
 606         u8 serv_name[64];       /* Server host name */
 607         u8 boot_file[128];      /* Name of boot file */
 608         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 609 };
 610
 611 /* packet ops */
 612 #define BOOTP_REQUEST   1
 613 #define BOOTP_REPLY     2
 614
 615 /* DHCP message types */
 616 #define DHCPDISCOVER    1
 617 #define DHCPOFFER       2
 618 #define DHCPREQUEST     3
 619 #define DHCPDECLINE     4
 620 #define DHCPACK         5
 621 #define DHCPNAK         6
 622 #define DHCPRELEASE     7
 623 #define DHCPINFORM      8
 624
 625 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 626
 627 static struct packet_type bootp_packet_type __initdata = {
 628         .type = cpu_to_be16(ETH_P_IP),
 629         .func = ic_bootp_recv,
 630 };
 631
 632
 633 /*
 634  *  Initialize DHCP/BOOTP extension fields in the request.
 635  */
 636
 637 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 638
 639 #ifdef IPCONFIG_DHCP
 640
 641 static void __init
 642 ic_dhcp_init_options(u8 *options)
 643 {
 644         u8 mt = ((ic_servaddr == NONE)
 645                  ? DHCPDISCOVER : DHCPREQUEST);
 646         u8 *e = options;
 647         int len;
 648
 649 #ifdef IPCONFIG_DEBUG
 650         printk("DHCP: Sending message type %d\n", mt);
 651 #endif
 652
 653         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 654         e += 4;
 655
 656         *e++ = 53;              /* DHCP message type */
 657         *e++ = 1;
 658         *e++ = mt;
 659
 660         if (mt == DHCPREQUEST) {
 661                 *e++ = 54;      /* Server ID (IP address) */
 662                 *e++ = 4;
 663                 memcpy(e, &ic_servaddr, 4);
 664                 e += 4;
 665
 666                 *e++ = 50;      /* Requested IP address */
 667                 *e++ = 4;
 668                 memcpy(e, &ic_myaddr, 4);
 669                 e += 4;
 670         }
 671
 672         /* always? */
 673         {
 674                 static const u8 ic_req_params[] = {
 675                         1,      /* Subnet mask */
 676                         3,      /* Default gateway */
 677                         6,      /* DNS server */
 678                         12,     /* Host name */
 679                         15,     /* Domain name */
 680                         17,     /* Boot path */
 681                         26,     /* MTU */
 682                         40,     /* NIS domain name */
 683                 };
 684
 685                 *e++ = 55;      /* Parameter request list */
 686                 *e++ = sizeof(ic_req_params);
 687                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 688                 e += sizeof(ic_req_params);
 689
 690                 if (ic_host_name_set) {
 691                         *e++ = 12;      /* host-name */
 692                         len = strlen(utsname()->nodename);
 693                         *e++ = len;
 694                         memcpy(e, utsname()->nodename, len);
 695                         e += len;
 696                 }
 697                 if (*vendor_class_identifier) {
 698                         pr_info("DHCP: sending class identifier \"%s\"\n",
 699                                 vendor_class_identifier);
 700                         *e++ = 60;      /* Class-identifier */
 701                         len = strlen(vendor_class_identifier);
 702                         *e++ = len;
 703                         memcpy(e, vendor_class_identifier, len);
 704                         e += len;
 705                 }
 706         }
 707
 708         *e++ = 255;     /* End of the list */
 709 }
 710
 711 #endif /* IPCONFIG_DHCP */
 712
 713 static void __init ic_bootp_init_ext(u8 *e)
 714 {
 715         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 716         e += 4;
 717         *e++ = 1;               /* Subnet mask request */
 718         *e++ = 4;
 719         e += 4;
 720         *e++ = 3;               /* Default gateway request */
 721         *e++ = 4;
 722         e += 4;
 723         *e++ = 5;               /* Name server request */
 724         *e++ = 8;
 725         e += 8;
 726         *e++ = 12;              /* Host name request */
 727         *e++ = 32;
 728         e += 32;
 729         *e++ = 40;              /* NIS Domain name request */
 730         *e++ = 32;
 731         e += 32;
 732         *e++ = 17;              /* Boot path */
 733         *e++ = 40;
 734         e += 40;
 735
 736         *e++ = 57;              /* set extension buffer size for reply */
 737         *e++ = 2;
 738         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 739         *e++ = 150;
 740
 741         *e++ = 255;             /* End of the list */
 742 }
 743
 744
 745 /*
 746  *  Predefine Nameservers
 747  */
 748 static inline void __init ic_nameservers_predef(void)
 749 {
 750         int i;
 751
 752         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 753                 ic_nameservers[i] = NONE;
 754 }
 755
 756 /*
 757  *  Initialize the DHCP/BOOTP mechanism.
 758  */
 759 static inline void __init ic_bootp_init(void)
 760 {
 761         ic_nameservers_predef();
 762
 763         dev_add_pack(&bootp_packet_type);
 764 }
 765
 766
 767 /*
 768  *  DHCP/BOOTP cleanup.
 769  */
 770 static inline void __init ic_bootp_cleanup(void)
 771 {
 772         dev_remove_pack(&bootp_packet_type);
 773 }
 774
 775
 776 /*
 777  *  Send DHCP/BOOTP request to single interface.
 778  */
 779 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 780 {
 781         struct net_device *dev = d->dev;
 782         struct sk_buff *skb;
 783         struct bootp_pkt *b;
 784         struct iphdr *h;
 785         int hlen = LL_RESERVED_SPACE(dev);
 786         int tlen = dev->needed_tailroom;
 787
 788         /* Allocate packet */
 789         skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
 790                         GFP_KERNEL);
 791         if (!skb)
 792                 return;
 793         skb_reserve(skb, hlen);
 794         b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
 795         memset(b, 0, sizeof(struct bootp_pkt));
 796
 797         /* Construct IP header */
 798         skb_reset_network_header(skb);
 799         h = ip_hdr(skb);
 800         h->version = 4;
 801         h->ihl = 5;
 802         h->tot_len = htons(sizeof(struct bootp_pkt));
 803         h->frag_off = htons(IP_DF);
 804         h->ttl = 64;
 805         h->protocol = IPPROTO_UDP;
 806         h->daddr = htonl(INADDR_BROADCAST);
 807         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 808
 809         /* Construct UDP header */
 810         b->udph.source = htons(68);
 811         b->udph.dest = htons(67);
 812         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 813         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 814
 815         /* Construct DHCP/BOOTP header */
 816         b->op = BOOTP_REQUEST;
 817         if (dev->type < 256) /* check for false types */
 818                 b->htype = dev->type;
 819         else if (dev->type == ARPHRD_FDDI)
 820                 b->htype = ARPHRD_ETHER;
 821         else {
 822                 printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
 823                 b->htype = dev->type; /* can cause undefined behavior */
 824         }
 825
 826         /* server_ip and your_ip address are both already zero per RFC2131 */
 827         b->hlen = dev->addr_len;
 828         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 829         b->secs = htons(jiffies_diff / HZ);
 830         b->xid = d->xid;
 831
 832         /* add DHCP options or BOOTP extensions */
 833 #ifdef IPCONFIG_DHCP
 834         if (ic_proto_enabled & IC_USE_DHCP)
 835                 ic_dhcp_init_options(b->exten);
 836         else
 837 #endif
 838                 ic_bootp_init_ext(b->exten);
 839
 840         /* Chain packet down the line... */
 841         skb->dev = dev;
 842         skb->protocol = htons(ETH_P_IP);
 843         if (dev_hard_header(skb, dev, ntohs(skb->protocol),
 844                             dev->broadcast, dev->dev_addr, skb->len) < 0) {
 845                 kfree_skb(skb);
 846                 printk("E");
 847                 return;
 848         }
 849
 850         if (dev_queue_xmit(skb) < 0)
 851                 printk("E");
 852 }
 853
 854
 855 /*
 856  *  Copy BOOTP-supplied string if not already set.
 857  */
 858 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 859 {
 860         if (!len)
 861                 return 0;
 862         if (len > max-1)
 863                 len = max-1;
 864         memcpy(dest, src, len);
 865         dest[len] = '\0';
 866         return 1;
 867 }
 868
 869
 870 /*
 871  *  Process BOOTP extensions.
 872  */
 873 static void __init ic_do_bootp_ext(u8 *ext)
 874 {
 875         u8 servers;
 876         int i;
 877         __be16 mtu;
 878
 879 #ifdef IPCONFIG_DEBUG
 880         u8 *c;
 881
 882         printk("DHCP/BOOTP: Got extension %d:",*ext);
 883         for (c=ext+2; c<ext+2+ext[1]; c++)
 884                 printk(" %02x", *c);
 885         printk("\n");
 886 #endif
 887
 888         switch (*ext++) {
 889         case 1:         /* Subnet mask */
 890                 if (ic_netmask == NONE)
 891                         memcpy(&ic_netmask, ext+1, 4);
 892                 break;
 893         case 3:         /* Default gateway */
 894                 if (ic_gateway == NONE)
 895                         memcpy(&ic_gateway, ext+1, 4);
 896                 break;
 897         case 6:         /* DNS server */
 898                 servers= *ext/4;
 899                 if (servers > CONF_NAMESERVERS_MAX)
 900                         servers = CONF_NAMESERVERS_MAX;
 901                 for (i = 0; i < servers; i++) {
 902                         if (ic_nameservers[i] == NONE)
 903                                 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 904                 }
 905                 break;
 906         case 12:        /* Host name */
 907                 ic_bootp_string(utsname()->nodename, ext+1, *ext,
 908                                 __NEW_UTS_LEN);
 909                 ic_host_name_set = 1;
 910                 break;
 911         case 15:        /* Domain name (DNS) */
 912                 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
 913                 break;
 914         case 17:        /* Root path */
 915                 if (!root_server_path[0])
 916                         ic_bootp_string(root_server_path, ext+1, *ext,
 917                                         sizeof(root_server_path));
 918                 break;
 919         case 26:        /* Interface MTU */
 920                 memcpy(&mtu, ext+1, sizeof(mtu));
 921                 ic_dev_mtu = ntohs(mtu);
 922                 break;
 923         case 40:        /* NIS Domain name (_not_ DNS) */
 924                 ic_bootp_string(utsname()->domainname, ext+1, *ext,
 925                                 __NEW_UTS_LEN);
 926                 break;
 927         }
 928 }
 929
 930
 931 /*
 932  *  Receive BOOTP reply.
 933  */
 934 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 935 {
 936         struct bootp_pkt *b;
 937         struct iphdr *h;
 938         struct ic_device *d;
 939         int len, ext_len;
 940
 941         if (!net_eq(dev_net(dev), &init_net))
 942                 goto drop;
 943
 944         /* Perform verifications before taking the lock.  */
 945         if (skb->pkt_type == PACKET_OTHERHOST)
 946                 goto drop;
 947
 948         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 949                 return NET_RX_DROP;
 950
 951         if (!pskb_may_pull(skb,
 952                            sizeof(struct iphdr) +
 953                            sizeof(struct udphdr)))
 954                 goto drop;
 955
 956         b = (struct bootp_pkt *)skb_network_header(skb);
 957         h = &b->iph;
 958
 959         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
 960                 goto drop;
 961
 962         /* Fragments are not supported */
 963         if (ip_is_fragment(h)) {
 964                 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
 965                 goto drop;
 966         }
 967
 968         if (skb->len < ntohs(h->tot_len))
 969                 goto drop;
 970
 971         if (ip_fast_csum((char *) h, h->ihl))
 972                 goto drop;
 973
 974         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
 975                 goto drop;
 976
 977         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
 978                 goto drop;
 979
 980         len = ntohs(b->udph.len) - sizeof(struct udphdr);
 981         ext_len = len - (sizeof(*b) -
 982                          sizeof(struct iphdr) -
 983                          sizeof(struct udphdr) -
 984                          sizeof(b->exten));
 985         if (ext_len < 0)
 986                 goto drop;
 987
 988         /* Ok the front looks good, make sure we can get at the rest.  */
 989         if (!pskb_may_pull(skb, skb->len))
 990                 goto drop;
 991
 992         b = (struct bootp_pkt *)skb_network_header(skb);
 993         h = &b->iph;
 994
 995         /* One reply at a time, please. */
 996         spin_lock(&ic_recv_lock);
 997
 998         /* If we already have a reply, just drop the packet */
 999         if (ic_got_reply)
1000                 goto drop_unlock;
1001
1002         /* Find the ic_device that the packet arrived on */
1003         d = ic_first_dev;
1004         while (d && d->dev != dev)
1005                 d = d->next;
1006         if (!d)
1007                 goto drop_unlock;  /* should never happen */
1008
1009         /* Is it a reply to our BOOTP request? */
1010         if (b->op != BOOTP_REPLY ||
1011             b->xid != d->xid) {
1012                 net_err_ratelimited("DHCP/BOOTP: Reply not for us, op[%x] xid[%x]\n",
1013                                     b->op, b->xid);
1014                 goto drop_unlock;
1015         }
1016
1017         /* Is it a reply for the device we are configuring? */
1018         if (b->xid != ic_dev_xid) {
1019                 net_err_ratelimited("DHCP/BOOTP: Ignoring delayed packet\n");
1020                 goto drop_unlock;
1021         }
1022
1023         /* Parse extensions */
1024         if (ext_len >= 4 &&
1025             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1026                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1027                 u8 *ext;
1028
1029 #ifdef IPCONFIG_DHCP
1030                 if (ic_proto_enabled & IC_USE_DHCP) {
1031                         __be32 server_id = NONE;
1032                         int mt = 0;
1033
1034                         ext = &b->exten[4];
1035                         while (ext < end && *ext != 0xff) {
1036                                 u8 *opt = ext++;
1037                                 if (*opt == 0)  /* Padding */
1038                                         continue;
1039                                 ext += *ext + 1;
1040                                 if (ext >= end)
1041                                         break;
1042                                 switch (*opt) {
1043                                 case 53:        /* Message type */
1044                                         if (opt[1])
1045                                                 mt = opt[2];
1046                                         break;
1047                                 case 54:        /* Server ID (IP address) */
1048                                         if (opt[1] >= 4)
1049                                                 memcpy(&server_id, opt + 2, 4);
1050                                         break;
1051                                 }
1052                         }
1053
1054 #ifdef IPCONFIG_DEBUG
1055                         printk("DHCP: Got message type %d\n", mt);
1056 #endif
1057
1058                         switch (mt) {
1059                         case DHCPOFFER:
1060                                 /* While in the process of accepting one offer,
1061                                  * ignore all others.
1062                                  */
1063                                 if (ic_myaddr != NONE)
1064                                         goto drop_unlock;
1065
1066                                 /* Let's accept that offer. */
1067                                 ic_myaddr = b->your_ip;
1068                                 ic_servaddr = server_id;
1069 #ifdef IPCONFIG_DEBUG
1070                                 printk("DHCP: Offered address %pI4 by server %pI4\n",
1071                                        &ic_myaddr, &ic_servaddr);
1072 #endif
1073                                 /* The DHCP indicated server address takes
1074                                  * precedence over the bootp header one if
1075                                  * they are different.
1076                                  */
1077                                 if ((server_id != NONE) &&
1078                                     (b->server_ip != server_id))
1079                                         b->server_ip = ic_servaddr;
1080                                 break;
1081
1082                         case DHCPACK:
1083                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1084                                         goto drop_unlock;
1085
1086                                 /* Yeah! */
1087                                 break;
1088
1089                         default:
1090                                 /* Urque.  Forget it*/
1091                                 ic_myaddr = NONE;
1092                                 ic_servaddr = NONE;
1093                                 goto drop_unlock;
1094                         }
1095
1096                         ic_dhcp_msgtype = mt;
1097
1098                 }
1099 #endif /* IPCONFIG_DHCP */
1100
1101                 ext = &b->exten[4];
1102                 while (ext < end && *ext != 0xff) {
1103                         u8 *opt = ext++;
1104                         if (*opt == 0)  /* Padding */
1105                                 continue;
1106                         ext += *ext + 1;
1107                         if (ext < end)
1108                                 ic_do_bootp_ext(opt);
1109                 }
1110         }
1111
1112         /* We have a winner! */
1113         ic_dev = dev;
1114         ic_myaddr = b->your_ip;
1115         ic_servaddr = b->server_ip;
1116         if (ic_gateway == NONE && b->relay_ip)
1117                 ic_gateway = b->relay_ip;
1118         if (ic_nameservers[0] == NONE)
1119                 ic_nameservers[0] = ic_servaddr;
1120         ic_got_reply = IC_BOOTP;
1121
1122 drop_unlock:
1123         /* Show's over.  Nothing to see here.  */
1124         spin_unlock(&ic_recv_lock);
1125
1126 drop:
1127         /* Throw the packet out. */
1128         kfree_skb(skb);
1129
1130         return 0;
1131 }
1132
1133
1134 #endif
1135
1136
1137 /*
1138  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1139  */
1140
1141 #ifdef IPCONFIG_DYNAMIC
1142
1143 static int __init ic_dynamic(void)
1144 {
1145         int retries;
1146         struct ic_device *d;
1147         unsigned long start_jiffies, timeout, jiff;
1148         int do_bootp = ic_proto_have_if & IC_BOOTP;
1149         int do_rarp = ic_proto_have_if & IC_RARP;
1150
1151         /*
1152          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1153          * This routine gets only called when some pieces of information
1154          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1155          */
1156         if (!ic_proto_enabled) {
1157                 pr_err("IP-Config: Incomplete network configuration information\n");
1158                 return -1;
1159         }
1160
1161 #ifdef IPCONFIG_BOOTP
1162         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1163                 pr_err("DHCP/BOOTP: No suitable device found\n");
1164 #endif
1165 #ifdef IPCONFIG_RARP
1166         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1167                 pr_err("RARP: No suitable device found\n");
1168 #endif
1169
1170         if (!ic_proto_have_if)
1171                 /* Error message already printed */
1172                 return -1;
1173
1174         /*
1175          * Setup protocols
1176          */
1177 #ifdef IPCONFIG_BOOTP
1178         if (do_bootp)
1179                 ic_bootp_init();
1180 #endif
1181 #ifdef IPCONFIG_RARP
1182         if (do_rarp)
1183                 ic_rarp_init();
1184 #endif
1185
1186         /*
1187          * Send requests and wait, until we get an answer. This loop
1188          * seems to be a terrible waste of CPU time, but actually there is
1189          * only one process running at all, so we don't need to use any
1190          * scheduler functions.
1191          * [Actually we could now, but the nothing else running note still
1192          *  applies.. - AC]
1193          */
1194         pr_notice("Sending %s%s%s requests .",
1195                   do_bootp
1196                   ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1197                   (do_bootp && do_rarp) ? " and " : "",
1198                   do_rarp ? "RARP" : "");
1199
1200         start_jiffies = jiffies;
1201         d = ic_first_dev;
1202         retries = CONF_SEND_RETRIES;
1203         get_random_bytes(&timeout, sizeof(timeout));
1204         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1205         for (;;) {
1206                 /* Track the device we are configuring */
1207                 ic_dev_xid = d->xid;
1208
1209 #ifdef IPCONFIG_BOOTP
1210                 if (do_bootp && (d->able & IC_BOOTP))
1211                         ic_bootp_send_if(d, jiffies - start_jiffies);
1212 #endif
1213 #ifdef IPCONFIG_RARP
1214                 if (do_rarp && (d->able & IC_RARP))
1215                         ic_rarp_send_if(d);
1216 #endif
1217
1218                 jiff = jiffies + (d->next ? CONF_INTER_TIMEOUT : timeout);
1219                 while (time_before(jiffies, jiff) && !ic_got_reply)
1220                         schedule_timeout_uninterruptible(1);
1221 #ifdef IPCONFIG_DHCP
1222                 /* DHCP isn't done until we get a DHCPACK. */
1223                 if ((ic_got_reply & IC_BOOTP) &&
1224                     (ic_proto_enabled & IC_USE_DHCP) &&
1225                     ic_dhcp_msgtype != DHCPACK) {
1226                         ic_got_reply = 0;
1227                         pr_cont(",");
1228                         continue;
1229                 }
1230 #endif /* IPCONFIG_DHCP */
1231
1232                 if (ic_got_reply) {
1233                         pr_cont(" OK\n");
1234                         break;
1235                 }
1236
1237                 if ((d = d->next))
1238                         continue;
1239
1240                 if (! --retries) {
1241                         pr_cont(" timed out!\n");
1242                         break;
1243                 }
1244
1245                 d = ic_first_dev;
1246
1247                 timeout = timeout CONF_TIMEOUT_MULT;
1248                 if (timeout > CONF_TIMEOUT_MAX)
1249                         timeout = CONF_TIMEOUT_MAX;
1250
1251                 pr_cont(".");
1252         }
1253
1254 #ifdef IPCONFIG_BOOTP
1255         if (do_bootp)
1256                 ic_bootp_cleanup();
1257 #endif
1258 #ifdef IPCONFIG_RARP
1259         if (do_rarp)
1260                 ic_rarp_cleanup();
1261 #endif
1262
1263         if (!ic_got_reply) {
1264                 ic_myaddr = NONE;
1265                 return -1;
1266         }
1267
1268         printk("IP-Config: Got %s answer from %pI4, ",
1269                 ((ic_got_reply & IC_RARP) ? "RARP"
1270                  : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1271                &ic_servaddr);
1272         pr_cont("my address is %pI4\n", &ic_myaddr);
1273
1274         return 0;
1275 }
1276
1277 #endif /* IPCONFIG_DYNAMIC */
1278
1279 #ifdef CONFIG_PROC_FS
1280
1281 static int pnp_seq_show(struct seq_file *seq, void *v)
1282 {
1283         int i;
1284
1285         if (ic_proto_used & IC_PROTO)
1286                 seq_printf(seq, "#PROTO: %s\n",
1287                            (ic_proto_used & IC_RARP) ? "RARP"
1288                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1289         else
1290                 seq_puts(seq, "#MANUAL\n");
1291
1292         if (ic_domain[0])
1293                 seq_printf(seq,
1294                            "domain %s\n", ic_domain);
1295         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1296                 if (ic_nameservers[i] != NONE)
1297                         seq_printf(seq, "nameserver %pI4\n",
1298                                    &ic_nameservers[i]);
1299         }
1300         if (ic_servaddr != NONE)
1301                 seq_printf(seq, "bootserver %pI4\n",
1302                            &ic_servaddr);
1303         return 0;
1304 }
1305
1306 static int pnp_seq_open(struct inode *indoe, struct file *file)
1307 {
1308         return single_open(file, pnp_seq_show, NULL);
1309 }
1310
1311 static const struct file_operations pnp_seq_fops = {
1312         .owner          = THIS_MODULE,
1313         .open           = pnp_seq_open,
1314         .read           = seq_read,
1315         .llseek         = seq_lseek,
1316         .release        = single_release,
1317 };
1318 #endif /* CONFIG_PROC_FS */
1319
1320 /*
1321  *  Extract IP address from the parameter string if needed. Note that we
1322  *  need to have root_server_addr set _before_ IPConfig gets called as it
1323  *  can override it.
1324  */
1325 __be32 __init root_nfs_parse_addr(char *name)
1326 {
1327         __be32 addr;
1328         int octets = 0;
1329         char *cp, *cq;
1330
1331         cp = cq = name;
1332         while (octets < 4) {
1333                 while (*cp >= '0' && *cp <= '9')
1334                         cp++;
1335                 if (cp == cq || cp - cq > 3)
1336                         break;
1337                 if (*cp == '.' || octets == 3)
1338                         octets++;
1339                 if (octets < 4)
1340                         cp++;
1341                 cq = cp;
1342         }
1343         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1344                 if (*cp == ':')
1345                         *cp++ = '\0';
1346                 addr = in_aton(name);
1347                 memmove(name, cp, strlen(cp) + 1);
1348         } else
1349                 addr = NONE;
1350
1351         return addr;
1352 }
1353
1354 #define DEVICE_WAIT_MAX         12 /* 12 seconds */
1355
1356 static int __init wait_for_devices(void)
1357 {
1358         int i;
1359
1360         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1361                 struct net_device *dev;
1362                 int found = 0;
1363
1364                 rtnl_lock();
1365                 for_each_netdev(&init_net, dev) {
1366                         if (ic_is_init_dev(dev)) {
1367                                 found = 1;
1368                                 break;
1369                         }
1370                 }
1371                 rtnl_unlock();
1372                 if (found)
1373                         return 0;
1374                 ssleep(1);
1375         }
1376         return -ENODEV;
1377 }
1378
1379 /*
1380  *      IP Autoconfig dispatcher.
1381  */
1382
1383 static int __init ip_auto_config(void)
1384 {
1385         __be32 addr;
1386 #ifdef IPCONFIG_DYNAMIC
1387         int retries = CONF_OPEN_RETRIES;
1388 #endif
1389         int err;
1390         unsigned int i;
1391
1392 #ifdef CONFIG_PROC_FS
1393         proc_net_fops_create(&init_net, "pnp", S_IRUGO, &pnp_seq_fops);
1394 #endif /* CONFIG_PROC_FS */
1395
1396         if (!ic_enable)
1397                 return 0;
1398
1399         DBG(("IP-Config: Entered.\n"));
1400 #ifdef IPCONFIG_DYNAMIC
1401  try_try_again:
1402 #endif
1403         /* Wait for devices to appear */
1404         err = wait_for_devices();
1405         if (err)
1406                 return err;
1407
1408         /* Setup all network devices */
1409         err = ic_open_devs();
1410         if (err)
1411                 return err;
1412
1413         /* Give drivers a chance to settle */
1414         msleep(CONF_POST_OPEN);
1415
1416         /*
1417          * If the config information is insufficient (e.g., our IP address or
1418          * IP address of the boot server is missing or we have multiple network
1419          * interfaces and no default was set), use BOOTP or RARP to get the
1420          * missing values.
1421          */
1422         if (ic_myaddr == NONE ||
1423 #ifdef CONFIG_ROOT_NFS
1424             (root_server_addr == NONE &&
1425              ic_servaddr == NONE &&
1426              ROOT_DEV == Root_NFS) ||
1427 #endif
1428             ic_first_dev->next) {
1429 #ifdef IPCONFIG_DYNAMIC
1430                 if (ic_dynamic() < 0) {
1431                         ic_close_devs();
1432
1433                         /*
1434                          * I don't know why, but sometimes the
1435                          * eepro100 driver (at least) gets upset and
1436                          * doesn't work the first time it's opened.
1437                          * But then if you close it and reopen it, it
1438                          * works just fine.  So we need to try that at
1439                          * least once before giving up.
1440                          *
1441                          * Also, if the root will be NFS-mounted, we
1442                          * have nowhere to go if DHCP fails.  So we
1443                          * just have to keep trying forever.
1444                          *
1445                          *                              -- Chip
1446                          */
1447 #ifdef CONFIG_ROOT_NFS
1448                         if (ROOT_DEV ==  Root_NFS) {
1449                                 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1450                                 goto try_try_again;
1451                         }
1452 #endif
1453
1454                         if (--retries) {
1455                                 pr_err("IP-Config: Reopening network devices...\n");
1456                                 goto try_try_again;
1457                         }
1458
1459                         /* Oh, well.  At least we tried. */
1460                         pr_err("IP-Config: Auto-configuration of network failed\n");
1461                         return -1;
1462                 }
1463 #else /* !DYNAMIC */
1464                 pr_err("IP-Config: Incomplete network configuration information\n");
1465                 ic_close_devs();
1466                 return -1;
1467 #endif /* IPCONFIG_DYNAMIC */
1468         } else {
1469                 /* Device selected manually or only one device -> use it */
1470                 ic_dev = ic_first_dev->dev;
1471         }
1472
1473         addr = root_nfs_parse_addr(root_server_path);
1474         if (root_server_addr == NONE)
1475                 root_server_addr = addr;
1476
1477         /*
1478          * Use defaults wherever applicable.
1479          */
1480         if (ic_defaults() < 0)
1481                 return -1;
1482
1483         /*
1484          * Close all network devices except the device we've
1485          * autoconfigured and set up routes.
1486          */
1487         ic_close_devs();
1488         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1489                 return -1;
1490
1491         /*
1492          * Record which protocol was actually used.
1493          */
1494 #ifdef IPCONFIG_DYNAMIC
1495         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1496 #endif
1497
1498 #ifndef IPCONFIG_SILENT
1499         /*
1500          * Clue in the operator.
1501          */
1502         pr_info("IP-Config: Complete:\n");
1503         pr_info("     device=%s, addr=%pI4, mask=%pI4, gw=%pI4\n",
1504                 ic_dev->name, &ic_myaddr, &ic_netmask, &ic_gateway);
1505         pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1506                 utsname()->nodename, ic_domain, utsname()->domainname);
1507         pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1508                 &ic_servaddr, &root_server_addr, root_server_path);
1509         if (ic_dev_mtu)
1510                 pr_cont(", mtu=%d", ic_dev_mtu);
1511         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1512                 if (ic_nameservers[i] != NONE) {
1513                         pr_info("     nameserver%u=%pI4",
1514                                 i, &ic_nameservers[i]);
1515                         break;
1516                 }
1517         for (i++; i < CONF_NAMESERVERS_MAX; i++)
1518                 if (ic_nameservers[i] != NONE)
1519                         pr_cont(", nameserver%u=%pI4\n", i, &ic_nameservers[i]);
1520 #endif /* !SILENT */
1521
1522         return 0;
1523 }
1524
1525 late_initcall(ip_auto_config);
1526
1527
1528 /*
1529  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1530  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1531  */
1532 static int __init ic_proto_name(char *name)
1533 {
1534         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1535                 return 1;
1536         }
1537         if (!strcmp(name, "off") || !strcmp(name, "none")) {
1538                 return 0;
1539         }
1540 #ifdef CONFIG_IP_PNP_DHCP
1541         else if (!strcmp(name, "dhcp")) {
1542                 ic_proto_enabled &= ~IC_RARP;
1543                 return 1;
1544         }
1545 #endif
1546 #ifdef CONFIG_IP_PNP_BOOTP
1547         else if (!strcmp(name, "bootp")) {
1548                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1549                 return 1;
1550         }
1551 #endif
1552 #ifdef CONFIG_IP_PNP_RARP
1553         else if (!strcmp(name, "rarp")) {
1554                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1555                 return 1;
1556         }
1557 #endif
1558 #ifdef IPCONFIG_DYNAMIC
1559         else if (!strcmp(name, "both")) {
1560                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1561                 return 1;
1562         }
1563 #endif
1564         return 0;
1565 }
1566
1567 static int __init ip_auto_config_setup(char *addrs)
1568 {
1569         char *cp, *ip, *dp;
1570         int num = 0;
1571
1572         ic_set_manually = 1;
1573         ic_enable = 1;
1574
1575         /*
1576          * If any dhcp, bootp etc options are set, leave autoconfig on
1577          * and skip the below static IP processing.
1578          */
1579         if (ic_proto_name(addrs))
1580                 return 1;
1581
1582         /* If no static IP is given, turn off autoconfig and bail.  */
1583         if (*addrs == 0 ||
1584             strcmp(addrs, "off") == 0 ||
1585             strcmp(addrs, "none") == 0) {
1586                 ic_enable = 0;
1587                 return 1;
1588         }
1589
1590         ic_nameservers_predef();
1591
1592         /* Parse string for static IP assignment.  */
1593         ip = addrs;
1594         while (ip && *ip) {
1595                 if ((cp = strchr(ip, ':')))
1596                         *cp++ = '\0';
1597                 if (strlen(ip) > 0) {
1598                         DBG(("IP-Config: Parameter #%d: `%s'\n", num, ip));
1599                         switch (num) {
1600                         case 0:
1601                                 if ((ic_myaddr = in_aton(ip)) == ANY)
1602                                         ic_myaddr = NONE;
1603                                 break;
1604                         case 1:
1605                                 if ((ic_servaddr = in_aton(ip)) == ANY)
1606                                         ic_servaddr = NONE;
1607                                 break;
1608                         case 2:
1609                                 if ((ic_gateway = in_aton(ip)) == ANY)
1610                                         ic_gateway = NONE;
1611                                 break;
1612                         case 3:
1613                                 if ((ic_netmask = in_aton(ip)) == ANY)
1614                                         ic_netmask = NONE;
1615                                 break;
1616                         case 4:
1617                                 if ((dp = strchr(ip, '.'))) {
1618                                         *dp++ = '\0';
1619                                         strlcpy(utsname()->domainname, dp,
1620                                                 sizeof(utsname()->domainname));
1621                                 }
1622                                 strlcpy(utsname()->nodename, ip,
1623                                         sizeof(utsname()->nodename));
1624                                 ic_host_name_set = 1;
1625                                 break;
1626                         case 5:
1627                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1628                                 break;
1629                         case 6:
1630                                 if (ic_proto_name(ip) == 0 &&
1631                                     ic_myaddr == NONE) {
1632                                         ic_enable = 0;
1633                                 }
1634                                 break;
1635                         case 7:
1636                                 if (CONF_NAMESERVERS_MAX >= 1) {
1637                                         ic_nameservers[0] = in_aton(ip);
1638                                         if (ic_nameservers[0] == ANY)
1639                                                 ic_nameservers[0] = NONE;
1640                                 }
1641                                 break;
1642                         case 8:
1643                                 if (CONF_NAMESERVERS_MAX >= 2) {
1644                                         ic_nameservers[1] = in_aton(ip);
1645                                         if (ic_nameservers[1] == ANY)
1646                                                 ic_nameservers[1] = NONE;
1647                                 }
1648                                 break;
1649                         }
1650                 }
1651                 ip = cp;
1652                 num++;
1653         }
1654
1655         return 1;
1656 }
1657 __setup("ip=", ip_auto_config_setup);
1658
1659 static int __init nfsaddrs_config_setup(char *addrs)
1660 {
1661         return ip_auto_config_setup(addrs);
1662 }
1663 __setup("nfsaddrs=", nfsaddrs_config_setup);
1664
1665 static int __init vendor_class_identifier_setup(char *addrs)
1666 {
1667         if (strlcpy(vendor_class_identifier, addrs,
1668                     sizeof(vendor_class_identifier))
1669             >= sizeof(vendor_class_identifier))
1670                 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"",
1671                         vendor_class_identifier);
1672         return 1;
1673 }
1674 __setup("dhcpclass=", vendor_class_identifier_setup);