net/ipv4/ipconfig.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
   4  *  user-supplied information to configure own IP address and routes.
   5  *
   6  *  Copyright (C) 1996-1998 Martin Mares <[email protected]>
   7  *
   8  *  Derived from network configuration code in fs/nfs/nfsroot.c,
   9  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
  10  *
  11  *  BOOTP rewritten to construct and analyse packets itself instead
  12  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
  13  *                                           -- MJ, December 1998
  14  *
  15  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
  16  *  initialization scheme.
  17  *      - Arnaldo Carvalho de Melo <[email protected]>, 08/11/1999
  18  *
  19  *  DHCP support added.  To users this looks like a whole separate
  20  *  protocol, but we know it's just a bag on the side of BOOTP.
  21  *              -- Chip Salzenberg <[email protected]>, May 2000
  22  *
  23  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
  24  *              -- Eric Biederman <[email protected]>, 30 Aug 2000
  25  *
  26  *  Merged changes from 2.2.19 into 2.4.3
  27  *              -- Eric Biederman <[email protected]>, 22 April Aug 2001
  28  *
  29  *  Multiple Nameservers in /proc/net/pnp
  30  *              --  Josef Siemes <[email protected]>, Aug 2002
  31  */
  32
  33 #include <linux/types.h>
  34 #include <linux/string.h>
  35 #include <linux/kernel.h>
  36 #include <linux/jiffies.h>
  37 #include <linux/random.h>
  38 #include <linux/init.h>
  39 #include <linux/utsname.h>
  40 #include <linux/in.h>
  41 #include <linux/if.h>
  42 #include <linux/inet.h>
  43 #include <linux/inetdevice.h>
  44 #include <linux/netdevice.h>
  45 #include <linux/if_arp.h>
  46 #include <linux/skbuff.h>
  47 #include <linux/ip.h>
  48 #include <linux/socket.h>
  49 #include <linux/route.h>
  50 #include <linux/udp.h>
  51 #include <linux/proc_fs.h>
  52 #include <linux/seq_file.h>
  53 #include <linux/major.h>
  54 #include <linux/root_dev.h>
  55 #include <linux/delay.h>
  56 #include <linux/nfs_fs.h>
  57 #include <linux/slab.h>
  58 #include <linux/export.h>
  59 #include <net/net_namespace.h>
  60 #include <net/arp.h>
  61 #include <net/dsa.h>
  62 #include <net/ip.h>
  63 #include <net/ipconfig.h>
  64 #include <net/route.h>
  65
  66 #include <linux/uaccess.h>
  67 #include <net/checksum.h>
  68 #include <asm/processor.h>
  69
  70 #if defined(CONFIG_IP_PNP_DHCP)
  71 #define IPCONFIG_DHCP
  72 #endif
  73 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
  74 #define IPCONFIG_BOOTP
  75 #endif
  76 #if defined(CONFIG_IP_PNP_RARP)
  77 #define IPCONFIG_RARP
  78 #endif
  79 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
  80 #define IPCONFIG_DYNAMIC
  81 #endif
  82
  83 /* Define the friendly delay before and after opening net devices */
  84 #define CONF_POST_OPEN          10      /* After opening: 10 msecs */
  85 #define CONF_CARRIER_TIMEOUT    120000  /* Wait for carrier timeout */
  86
  87 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
  88 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
  89 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
  90 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
  91 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
  92 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
  93 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
  94 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
  95                                            - '3' from resolv.h */
  96
  97 #define NONE cpu_to_be32(INADDR_NONE)
  98 #define ANY cpu_to_be32(INADDR_ANY)
  99
 100 /*
 101  * Public IP configuration
 102  */
 103
 104 /* This is used by platforms which might be able to set the ipconfig
 105  * variables using firmware environment vars.  If this is set, it will
 106  * ignore such firmware variables.
 107  */
 108 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
 109
 110 static int ic_enable __initdata;                /* IP config enabled? */
 111
 112 /* Protocol choice */
 113 int ic_proto_enabled __initdata = 0
 114 #ifdef IPCONFIG_BOOTP
 115                         | IC_BOOTP
 116 #endif
 117 #ifdef CONFIG_IP_PNP_DHCP
 118                         | IC_USE_DHCP
 119 #endif
 120 #ifdef IPCONFIG_RARP
 121                         | IC_RARP
 122 #endif
 123                         ;
 124
 125 static int ic_host_name_set __initdata; /* Host name set by us? */
 126
 127 __be32 ic_myaddr = NONE;                /* My IP address */
 128 static __be32 ic_netmask = NONE;        /* Netmask for local subnet */
 129 __be32 ic_gateway = NONE;       /* Gateway IP address */
 130
 131 #ifdef IPCONFIG_DYNAMIC
 132 static __be32 ic_addrservaddr = NONE;   /* IP Address of the IP addresses'server */
 133 #endif
 134
 135 __be32 ic_servaddr = NONE;      /* Boot server IP address */
 136
 137 __be32 root_server_addr = NONE; /* Address of NFS server */
 138 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
 139
 140 /* vendor class identifier */
 141 static char vendor_class_identifier[253] __initdata;
 142
 143 #if defined(CONFIG_IP_PNP_DHCP)
 144 static char dhcp_client_identifier[253] __initdata;
 145 #endif
 146
 147 /* Persistent data: */
 148
 149 #ifdef IPCONFIG_DYNAMIC
 150 static int ic_proto_used;                       /* Protocol used, if any */
 151 #else
 152 #define ic_proto_used 0
 153 #endif
 154 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
 155 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
 156
 157 /*
 158  * Private state.
 159  */
 160
 161 /* Name of user-selected boot device */
 162 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 163
 164 /* Protocols supported by available interfaces */
 165 static int ic_proto_have_if __initdata;
 166
 167 /* MTU for boot device */
 168 static int ic_dev_mtu __initdata;
 169
 170 #ifdef IPCONFIG_DYNAMIC
 171 static DEFINE_SPINLOCK(ic_recv_lock);
 172 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
 173 #endif
 174 #ifdef IPCONFIG_DHCP
 175 static int ic_dhcp_msgtype __initdata;  /* DHCP msg type received */
 176 #endif
 177
 178
 179 /*
 180  *      Network devices
 181  */
 182
 183 struct ic_device {
 184         struct ic_device *next;
 185         struct net_device *dev;
 186         unsigned short flags;
 187         short able;
 188         __be32 xid;
 189 };
 190
 191 static struct ic_device *ic_first_dev __initdata;       /* List of open device */
 192 static struct ic_device *ic_dev __initdata;             /* Selected device */
 193
 194 static bool __init ic_is_init_dev(struct net_device *dev)
 195 {
 196         if (dev->flags & IFF_LOOPBACK)
 197                 return false;
 198         return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 199             (!(dev->flags & IFF_LOOPBACK) &&
 200              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 201              strncmp(dev->name, "dummy", 5));
 202 }
 203
 204 static int __init ic_open_devs(void)
 205 {
 206         struct ic_device *d, **last;
 207         struct net_device *dev;
 208         unsigned short oflags;
 209         unsigned long start, next_msg;
 210
 211         last = &ic_first_dev;
 212         rtnl_lock();
 213
 214         /* bring loopback and DSA master network devices up first */
 215         for_each_netdev(&init_net, dev) {
 216                 if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
 217                         continue;
 218                 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
 219                         pr_err("IP-Config: Failed to open %s\n", dev->name);
 220         }
 221
 222         for_each_netdev(&init_net, dev) {
 223                 if (ic_is_init_dev(dev)) {
 224                         int able = 0;
 225                         if (dev->mtu >= 364)
 226                                 able |= IC_BOOTP;
 227                         else
 228                                 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
 229                                         dev->name, dev->mtu);
 230                         if (!(dev->flags & IFF_NOARP))
 231                                 able |= IC_RARP;
 232                         able &= ic_proto_enabled;
 233                         if (ic_proto_enabled && !able)
 234                                 continue;
 235                         oflags = dev->flags;
 236                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
 237                                 pr_err("IP-Config: Failed to open %s\n",
 238                                        dev->name);
 239                                 continue;
 240                         }
 241                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 242                                 rtnl_unlock();
 243                                 return -ENOMEM;
 244                         }
 245                         d->dev = dev;
 246                         *last = d;
 247                         last = &d->next;
 248                         d->flags = oflags;
 249                         d->able = able;
 250                         if (able & IC_BOOTP)
 251                                 get_random_bytes(&d->xid, sizeof(__be32));
 252                         else
 253                                 d->xid = 0;
 254                         ic_proto_have_if |= able;
 255                         pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
 256                                  dev->name, able, d->xid);
 257                 }
 258         }
 259
 260         /* no point in waiting if we could not bring up at least one device */
 261         if (!ic_first_dev)
 262                 goto have_carrier;
 263
 264         /* wait for a carrier on at least one device */
 265         start = jiffies;
 266         next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
 267         while (time_before(jiffies, start +
 268                            msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
 269                 int wait, elapsed;
 270
 271                 for_each_netdev(&init_net, dev)
 272                         if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
 273                                 goto have_carrier;
 274
 275                 msleep(1);
 276
 277                 if (time_before(jiffies, next_msg))
 278                         continue;
 279
 280                 elapsed = jiffies_to_msecs(jiffies - start);
 281                 wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
 282                 pr_info("Waiting up to %d more seconds for network.\n", wait);
 283                 next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
 284         }
 285 have_carrier:
 286         rtnl_unlock();
 287
 288         *last = NULL;
 289
 290         if (!ic_first_dev) {
 291                 if (user_dev_name[0])
 292                         pr_err("IP-Config: Device `%s' not found\n",
 293                                user_dev_name);
 294                 else
 295                         pr_err("IP-Config: No network devices available\n");
 296                 return -ENODEV;
 297         }
 298         return 0;
 299 }
 300
 301 static void __init ic_close_devs(void)
 302 {
 303         struct ic_device *d, *next;
 304         struct net_device *dev;
 305
 306         rtnl_lock();
 307         next = ic_first_dev;
 308         while ((d = next)) {
 309                 next = d->next;
 310                 dev = d->dev;
 311                 if (d != ic_dev && !netdev_uses_dsa(dev)) {
 312                         pr_debug("IP-Config: Downing %s\n", dev->name);
 313                         dev_change_flags(dev, d->flags);
 314                 }
 315                 kfree(d);
 316         }
 317         rtnl_unlock();
 318 }
 319
 320 /*
 321  *      Interface to various network functions.
 322  */
 323
 324 static inline void
 325 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
 326 {
 327         sin->sin_family = AF_INET;
 328         sin->sin_addr.s_addr = addr;
 329         sin->sin_port = port;
 330 }
 331
 332 static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
 333 {
 334         int res;
 335
 336         mm_segment_t oldfs = get_fs();
 337         set_fs(get_ds());
 338         res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
 339         set_fs(oldfs);
 340         return res;
 341 }
 342
 343 static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
 344 {
 345         int res;
 346
 347         mm_segment_t oldfs = get_fs();
 348         set_fs(get_ds());
 349         res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
 350         set_fs(oldfs);
 351         return res;
 352 }
 353
 354 static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
 355 {
 356         int res;
 357
 358         mm_segment_t oldfs = get_fs();
 359         set_fs(get_ds());
 360         res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
 361         set_fs(oldfs);
 362         return res;
 363 }
 364
 365 /*
 366  *      Set up interface addresses and routes.
 367  */
 368
 369 static int __init ic_setup_if(void)
 370 {
 371         struct ifreq ir;
 372         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 373         int err;
 374
 375         memset(&ir, 0, sizeof(ir));
 376         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
 377         set_sockaddr(sin, ic_myaddr, 0);
 378         if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
 379                 pr_err("IP-Config: Unable to set interface address (%d)\n",
 380                        err);
 381                 return -1;
 382         }
 383         set_sockaddr(sin, ic_netmask, 0);
 384         if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
 385                 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
 386                        err);
 387                 return -1;
 388         }
 389         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 390         if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
 391                 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
 392                        err);
 393                 return -1;
 394         }
 395         /* Handle the case where we need non-standard MTU on the boot link (a network
 396          * using jumbo frames, for instance).  If we can't set the mtu, don't error
 397          * out, we'll try to muddle along.
 398          */
 399         if (ic_dev_mtu != 0) {
 400                 strcpy(ir.ifr_name, ic_dev->dev->name);
 401                 ir.ifr_mtu = ic_dev_mtu;
 402                 if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
 403                         pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
 404                                ic_dev_mtu, err);
 405         }
 406         return 0;
 407 }
 408
 409 static int __init ic_setup_routes(void)
 410 {
 411         /* No need to setup device routes, only the default route... */
 412
 413         if (ic_gateway != NONE) {
 414                 struct rtentry rm;
 415                 int err;
 416
 417                 memset(&rm, 0, sizeof(rm));
 418                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 419                         pr_err("IP-Config: Gateway not on directly connected network\n");
 420                         return -1;
 421                 }
 422                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 423                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 424                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 425                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 426                 if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
 427                         pr_err("IP-Config: Cannot add default route (%d)\n",
 428                                err);
 429                         return -1;
 430                 }
 431         }
 432
 433         return 0;
 434 }
 435
 436 /*
 437  *      Fill in default values for all missing parameters.
 438  */
 439
 440 static int __init ic_defaults(void)
 441 {
 442         /*
 443          *      At this point we have no userspace running so need not
 444          *      claim locks on system_utsname
 445          */
 446
 447         if (!ic_host_name_set)
 448                 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
 449
 450         if (root_server_addr == NONE)
 451                 root_server_addr = ic_servaddr;
 452
 453         if (ic_netmask == NONE) {
 454                 if (IN_CLASSA(ntohl(ic_myaddr)))
 455                         ic_netmask = htonl(IN_CLASSA_NET);
 456                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 457                         ic_netmask = htonl(IN_CLASSB_NET);
 458                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 459                         ic_netmask = htonl(IN_CLASSC_NET);
 460                 else {
 461                         pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
 462                                &ic_myaddr);
 463                         return -1;
 464                 }
 465                 pr_notice("IP-Config: Guessing netmask %pI4\n",
 466                           &ic_netmask);
 467         }
 468
 469         return 0;
 470 }
 471
 472 /*
 473  *      RARP support.
 474  */
 475
 476 #ifdef IPCONFIG_RARP
 477
 478 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 479
 480 static struct packet_type rarp_packet_type __initdata = {
 481         .type = cpu_to_be16(ETH_P_RARP),
 482         .func = ic_rarp_recv,
 483 };
 484
 485 static inline void __init ic_rarp_init(void)
 486 {
 487         dev_add_pack(&rarp_packet_type);
 488 }
 489
 490 static inline void __init ic_rarp_cleanup(void)
 491 {
 492         dev_remove_pack(&rarp_packet_type);
 493 }
 494
 495 /*
 496  *  Process received RARP packet.
 497  */
 498 static int __init
 499 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 500 {
 501         struct arphdr *rarp;
 502         unsigned char *rarp_ptr;
 503         __be32 sip, tip;
 504         unsigned char *tha;             /* t for "target" */
 505         struct ic_device *d;
 506
 507         if (!net_eq(dev_net(dev), &init_net))
 508                 goto drop;
 509
 510         skb = skb_share_check(skb, GFP_ATOMIC);
 511         if (!skb)
 512                 return NET_RX_DROP;
 513
 514         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 515                 goto drop;
 516
 517         /* Basic sanity checks can be done without the lock.  */
 518         rarp = (struct arphdr *)skb_transport_header(skb);
 519
 520         /* If this test doesn't pass, it's not IP, or we should
 521          * ignore it anyway.
 522          */
 523         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 524                 goto drop;
 525
 526         /* If it's not a RARP reply, delete it. */
 527         if (rarp->ar_op != htons(ARPOP_RREPLY))
 528                 goto drop;
 529
 530         /* If it's not Ethernet, delete it. */
 531         if (rarp->ar_pro != htons(ETH_P_IP))
 532                 goto drop;
 533
 534         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
 535                 goto drop;
 536
 537         /* OK, it is all there and looks valid, process... */
 538         rarp = (struct arphdr *)skb_transport_header(skb);
 539         rarp_ptr = (unsigned char *) (rarp + 1);
 540
 541         /* One reply at a time, please. */
 542         spin_lock(&ic_recv_lock);
 543
 544         /* If we already have a reply, just drop the packet */
 545         if (ic_got_reply)
 546                 goto drop_unlock;
 547
 548         /* Find the ic_device that the packet arrived on */
 549         d = ic_first_dev;
 550         while (d && d->dev != dev)
 551                 d = d->next;
 552         if (!d)
 553                 goto drop_unlock;       /* should never happen */
 554
 555         /* Extract variable-width fields */
 556         rarp_ptr += dev->addr_len;
 557         memcpy(&sip, rarp_ptr, 4);
 558         rarp_ptr += 4;
 559         tha = rarp_ptr;
 560         rarp_ptr += dev->addr_len;
 561         memcpy(&tip, rarp_ptr, 4);
 562
 563         /* Discard packets which are not meant for us. */
 564         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 565                 goto drop_unlock;
 566
 567         /* Discard packets which are not from specified server. */
 568         if (ic_servaddr != NONE && ic_servaddr != sip)
 569                 goto drop_unlock;
 570
 571         /* We have a winner! */
 572         ic_dev = d;
 573         if (ic_myaddr == NONE)
 574                 ic_myaddr = tip;
 575         ic_servaddr = sip;
 576         ic_addrservaddr = sip;
 577         ic_got_reply = IC_RARP;
 578
 579 drop_unlock:
 580         /* Show's over.  Nothing to see here.  */
 581         spin_unlock(&ic_recv_lock);
 582
 583 drop:
 584         /* Throw the packet out. */
 585         kfree_skb(skb);
 586         return 0;
 587 }
 588
 589
 590 /*
 591  *  Send RARP request packet over a single interface.
 592  */
 593 static void __init ic_rarp_send_if(struct ic_device *d)
 594 {
 595         struct net_device *dev = d->dev;
 596         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 597                  dev->dev_addr, dev->dev_addr);
 598 }
 599 #endif
 600
 601 /*
 602  *  Predefine Nameservers
 603  */
 604 static inline void __init ic_nameservers_predef(void)
 605 {
 606         int i;
 607
 608         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 609                 ic_nameservers[i] = NONE;
 610 }
 611
 612 /*
 613  *      DHCP/BOOTP support.
 614  */
 615
 616 #ifdef IPCONFIG_BOOTP
 617
 618 struct bootp_pkt {              /* BOOTP packet format */
 619         struct iphdr iph;       /* IP header */
 620         struct udphdr udph;     /* UDP header */
 621         u8 op;                  /* 1=request, 2=reply */
 622         u8 htype;               /* HW address type */
 623         u8 hlen;                /* HW address length */
 624         u8 hops;                /* Used only by gateways */
 625         __be32 xid;             /* Transaction ID */
 626         __be16 secs;            /* Seconds since we started */
 627         __be16 flags;           /* Just what it says */
 628         __be32 client_ip;               /* Client's IP address if known */
 629         __be32 your_ip;         /* Assigned IP address */
 630         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
 631         __be32 relay_ip;                /* IP address of BOOTP relay */
 632         u8 hw_addr[16];         /* Client's HW address */
 633         u8 serv_name[64];       /* Server host name */
 634         u8 boot_file[128];      /* Name of boot file */
 635         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 636 };
 637
 638 /* packet ops */
 639 #define BOOTP_REQUEST   1
 640 #define BOOTP_REPLY     2
 641
 642 /* DHCP message types */
 643 #define DHCPDISCOVER    1
 644 #define DHCPOFFER       2
 645 #define DHCPREQUEST     3
 646 #define DHCPDECLINE     4
 647 #define DHCPACK         5
 648 #define DHCPNAK         6
 649 #define DHCPRELEASE     7
 650 #define DHCPINFORM      8
 651
 652 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 653
 654 static struct packet_type bootp_packet_type __initdata = {
 655         .type = cpu_to_be16(ETH_P_IP),
 656         .func = ic_bootp_recv,
 657 };
 658
 659 /*
 660  *  Initialize DHCP/BOOTP extension fields in the request.
 661  */
 662
 663 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 664
 665 #ifdef IPCONFIG_DHCP
 666
 667 static void __init
 668 ic_dhcp_init_options(u8 *options, struct ic_device *d)
 669 {
 670         u8 mt = ((ic_servaddr == NONE)
 671                  ? DHCPDISCOVER : DHCPREQUEST);
 672         u8 *e = options;
 673         int len;
 674
 675         pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
 676
 677         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 678         e += 4;
 679
 680         *e++ = 53;              /* DHCP message type */
 681         *e++ = 1;
 682         *e++ = mt;
 683
 684         if (mt == DHCPREQUEST) {
 685                 *e++ = 54;      /* Server ID (IP address) */
 686                 *e++ = 4;
 687                 memcpy(e, &ic_servaddr, 4);
 688                 e += 4;
 689
 690                 *e++ = 50;      /* Requested IP address */
 691                 *e++ = 4;
 692                 memcpy(e, &ic_myaddr, 4);
 693                 e += 4;
 694         }
 695
 696         /* always? */
 697         {
 698                 static const u8 ic_req_params[] = {
 699                         1,      /* Subnet mask */
 700                         3,      /* Default gateway */
 701                         6,      /* DNS server */
 702                         12,     /* Host name */
 703                         15,     /* Domain name */
 704                         17,     /* Boot path */
 705                         26,     /* MTU */
 706                         40,     /* NIS domain name */
 707                 };
 708
 709                 *e++ = 55;      /* Parameter request list */
 710                 *e++ = sizeof(ic_req_params);
 711                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 712                 e += sizeof(ic_req_params);
 713
 714                 if (ic_host_name_set) {
 715                         *e++ = 12;      /* host-name */
 716                         len = strlen(utsname()->nodename);
 717                         *e++ = len;
 718                         memcpy(e, utsname()->nodename, len);
 719                         e += len;
 720                 }
 721                 if (*vendor_class_identifier) {
 722                         pr_info("DHCP: sending class identifier \"%s\"\n",
 723                                 vendor_class_identifier);
 724                         *e++ = 60;      /* Class-identifier */
 725                         len = strlen(vendor_class_identifier);
 726                         *e++ = len;
 727                         memcpy(e, vendor_class_identifier, len);
 728                         e += len;
 729                 }
 730                 len = strlen(dhcp_client_identifier + 1);
 731                 /* the minimum length of identifier is 2, include 1 byte type,
 732                  * and can not be larger than the length of options
 733                  */
 734                 if (len >= 1 && len < 312 - (e - options) - 1) {
 735                         *e++ = 61;
 736                         *e++ = len + 1;
 737                         memcpy(e, dhcp_client_identifier, len + 1);
 738                         e += len + 1;
 739                 }
 740         }
 741
 742         *e++ = 255;     /* End of the list */
 743 }
 744
 745 #endif /* IPCONFIG_DHCP */
 746
 747 static void __init ic_bootp_init_ext(u8 *e)
 748 {
 749         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 750         e += 4;
 751         *e++ = 1;               /* Subnet mask request */
 752         *e++ = 4;
 753         e += 4;
 754         *e++ = 3;               /* Default gateway request */
 755         *e++ = 4;
 756         e += 4;
 757         *e++ = 5;               /* Name server request */
 758         *e++ = 8;
 759         e += 8;
 760         *e++ = 12;              /* Host name request */
 761         *e++ = 32;
 762         e += 32;
 763         *e++ = 40;              /* NIS Domain name request */
 764         *e++ = 32;
 765         e += 32;
 766         *e++ = 17;              /* Boot path */
 767         *e++ = 40;
 768         e += 40;
 769
 770         *e++ = 57;              /* set extension buffer size for reply */
 771         *e++ = 2;
 772         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 773         *e++ = 150;
 774
 775         *e++ = 255;             /* End of the list */
 776 }
 777
 778
 779 /*
 780  *  Initialize the DHCP/BOOTP mechanism.
 781  */
 782 static inline void __init ic_bootp_init(void)
 783 {
 784         ic_nameservers_predef();
 785
 786         dev_add_pack(&bootp_packet_type);
 787 }
 788
 789
 790 /*
 791  *  DHCP/BOOTP cleanup.
 792  */
 793 static inline void __init ic_bootp_cleanup(void)
 794 {
 795         dev_remove_pack(&bootp_packet_type);
 796 }
 797
 798
 799 /*
 800  *  Send DHCP/BOOTP request to single interface.
 801  */
 802 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 803 {
 804         struct net_device *dev = d->dev;
 805         struct sk_buff *skb;
 806         struct bootp_pkt *b;
 807         struct iphdr *h;
 808         int hlen = LL_RESERVED_SPACE(dev);
 809         int tlen = dev->needed_tailroom;
 810
 811         /* Allocate packet */
 812         skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
 813                         GFP_KERNEL);
 814         if (!skb)
 815                 return;
 816         skb_reserve(skb, hlen);
 817         b = skb_put_zero(skb, sizeof(struct bootp_pkt));
 818
 819         /* Construct IP header */
 820         skb_reset_network_header(skb);
 821         h = ip_hdr(skb);
 822         h->version = 4;
 823         h->ihl = 5;
 824         h->tot_len = htons(sizeof(struct bootp_pkt));
 825         h->frag_off = htons(IP_DF);
 826         h->ttl = 64;
 827         h->protocol = IPPROTO_UDP;
 828         h->daddr = htonl(INADDR_BROADCAST);
 829         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 830
 831         /* Construct UDP header */
 832         b->udph.source = htons(68);
 833         b->udph.dest = htons(67);
 834         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 835         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 836
 837         /* Construct DHCP/BOOTP header */
 838         b->op = BOOTP_REQUEST;
 839         if (dev->type < 256) /* check for false types */
 840                 b->htype = dev->type;
 841         else if (dev->type == ARPHRD_FDDI)
 842                 b->htype = ARPHRD_ETHER;
 843         else {
 844                 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
 845                         dev->name);
 846                 b->htype = dev->type; /* can cause undefined behavior */
 847         }
 848
 849         /* server_ip and your_ip address are both already zero per RFC2131 */
 850         b->hlen = dev->addr_len;
 851         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 852         b->secs = htons(jiffies_diff / HZ);
 853         b->xid = d->xid;
 854
 855         /* add DHCP options or BOOTP extensions */
 856 #ifdef IPCONFIG_DHCP
 857         if (ic_proto_enabled & IC_USE_DHCP)
 858                 ic_dhcp_init_options(b->exten, d);
 859         else
 860 #endif
 861                 ic_bootp_init_ext(b->exten);
 862
 863         /* Chain packet down the line... */
 864         skb->dev = dev;
 865         skb->protocol = htons(ETH_P_IP);
 866         if (dev_hard_header(skb, dev, ntohs(skb->protocol),
 867                             dev->broadcast, dev->dev_addr, skb->len) < 0) {
 868                 kfree_skb(skb);
 869                 printk("E");
 870                 return;
 871         }
 872
 873         if (dev_queue_xmit(skb) < 0)
 874                 printk("E");
 875 }
 876
 877
 878 /*
 879  *  Copy BOOTP-supplied string if not already set.
 880  */
 881 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 882 {
 883         if (!len)
 884                 return 0;
 885         if (len > max-1)
 886                 len = max-1;
 887         memcpy(dest, src, len);
 888         dest[len] = '\0';
 889         return 1;
 890 }
 891
 892
 893 /*
 894  *  Process BOOTP extensions.
 895  */
 896 static void __init ic_do_bootp_ext(u8 *ext)
 897 {
 898         u8 servers;
 899         int i;
 900         __be16 mtu;
 901
 902         u8 *c;
 903
 904         pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
 905         for (c=ext+2; c<ext+2+ext[1]; c++)
 906                 pr_debug(" %02x", *c);
 907         pr_debug("\n");
 908
 909         switch (*ext++) {
 910         case 1:         /* Subnet mask */
 911                 if (ic_netmask == NONE)
 912                         memcpy(&ic_netmask, ext+1, 4);
 913                 break;
 914         case 3:         /* Default gateway */
 915                 if (ic_gateway == NONE)
 916                         memcpy(&ic_gateway, ext+1, 4);
 917                 break;
 918         case 6:         /* DNS server */
 919                 servers= *ext/4;
 920                 if (servers > CONF_NAMESERVERS_MAX)
 921                         servers = CONF_NAMESERVERS_MAX;
 922                 for (i = 0; i < servers; i++) {
 923                         if (ic_nameservers[i] == NONE)
 924                                 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 925                 }
 926                 break;
 927         case 12:        /* Host name */
 928                 ic_bootp_string(utsname()->nodename, ext+1, *ext,
 929                                 __NEW_UTS_LEN);
 930                 ic_host_name_set = 1;
 931                 break;
 932         case 15:        /* Domain name (DNS) */
 933                 ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
 934                 break;
 935         case 17:        /* Root path */
 936                 if (!root_server_path[0])
 937                         ic_bootp_string(root_server_path, ext+1, *ext,
 938                                         sizeof(root_server_path));
 939                 break;
 940         case 26:        /* Interface MTU */
 941                 memcpy(&mtu, ext+1, sizeof(mtu));
 942                 ic_dev_mtu = ntohs(mtu);
 943                 break;
 944         case 40:        /* NIS Domain name (_not_ DNS) */
 945                 ic_bootp_string(utsname()->domainname, ext+1, *ext,
 946                                 __NEW_UTS_LEN);
 947                 break;
 948         }
 949 }
 950
 951
 952 /*
 953  *  Receive BOOTP reply.
 954  */
 955 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 956 {
 957         struct bootp_pkt *b;
 958         struct iphdr *h;
 959         struct ic_device *d;
 960         int len, ext_len;
 961
 962         if (!net_eq(dev_net(dev), &init_net))
 963                 goto drop;
 964
 965         /* Perform verifications before taking the lock.  */
 966         if (skb->pkt_type == PACKET_OTHERHOST)
 967                 goto drop;
 968
 969         skb = skb_share_check(skb, GFP_ATOMIC);
 970         if (!skb)
 971                 return NET_RX_DROP;
 972
 973         if (!pskb_may_pull(skb,
 974                            sizeof(struct iphdr) +
 975                            sizeof(struct udphdr)))
 976                 goto drop;
 977
 978         b = (struct bootp_pkt *)skb_network_header(skb);
 979         h = &b->iph;
 980
 981         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
 982                 goto drop;
 983
 984         /* Fragments are not supported */
 985         if (ip_is_fragment(h)) {
 986                 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
 987                 goto drop;
 988         }
 989
 990         if (skb->len < ntohs(h->tot_len))
 991                 goto drop;
 992
 993         if (ip_fast_csum((char *) h, h->ihl))
 994                 goto drop;
 995
 996         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
 997                 goto drop;
 998
 999         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1000                 goto drop;
1001
1002         len = ntohs(b->udph.len) - sizeof(struct udphdr);
1003         ext_len = len - (sizeof(*b) -
1004                          sizeof(struct iphdr) -
1005                          sizeof(struct udphdr) -
1006                          sizeof(b->exten));
1007         if (ext_len < 0)
1008                 goto drop;
1009
1010         /* Ok the front looks good, make sure we can get at the rest.  */
1011         if (!pskb_may_pull(skb, skb->len))
1012                 goto drop;
1013
1014         b = (struct bootp_pkt *)skb_network_header(skb);
1015         h = &b->iph;
1016
1017         /* One reply at a time, please. */
1018         spin_lock(&ic_recv_lock);
1019
1020         /* If we already have a reply, just drop the packet */
1021         if (ic_got_reply)
1022                 goto drop_unlock;
1023
1024         /* Find the ic_device that the packet arrived on */
1025         d = ic_first_dev;
1026         while (d && d->dev != dev)
1027                 d = d->next;
1028         if (!d)
1029                 goto drop_unlock;  /* should never happen */
1030
1031         /* Is it a reply to our BOOTP request? */
1032         if (b->op != BOOTP_REPLY ||
1033             b->xid != d->xid) {
1034                 net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1035                                     d->dev->name, b->op, b->xid);
1036                 goto drop_unlock;
1037         }
1038
1039         /* Parse extensions */
1040         if (ext_len >= 4 &&
1041             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1042                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1043                 u8 *ext;
1044
1045 #ifdef IPCONFIG_DHCP
1046                 if (ic_proto_enabled & IC_USE_DHCP) {
1047                         __be32 server_id = NONE;
1048                         int mt = 0;
1049
1050                         ext = &b->exten[4];
1051                         while (ext < end && *ext != 0xff) {
1052                                 u8 *opt = ext++;
1053                                 if (*opt == 0)  /* Padding */
1054                                         continue;
1055                                 ext += *ext + 1;
1056                                 if (ext >= end)
1057                                         break;
1058                                 switch (*opt) {
1059                                 case 53:        /* Message type */
1060                                         if (opt[1])
1061                                                 mt = opt[2];
1062                                         break;
1063                                 case 54:        /* Server ID (IP address) */
1064                                         if (opt[1] >= 4)
1065                                                 memcpy(&server_id, opt + 2, 4);
1066                                         break;
1067                                 }
1068                         }
1069
1070                         pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
1071
1072                         switch (mt) {
1073                         case DHCPOFFER:
1074                                 /* While in the process of accepting one offer,
1075                                  * ignore all others.
1076                                  */
1077                                 if (ic_myaddr != NONE)
1078                                         goto drop_unlock;
1079
1080                                 /* Let's accept that offer. */
1081                                 ic_myaddr = b->your_ip;
1082                                 ic_servaddr = server_id;
1083                                 pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1084                                          &ic_myaddr, &b->iph.saddr);
1085                                 /* The DHCP indicated server address takes
1086                                  * precedence over the bootp header one if
1087                                  * they are different.
1088                                  */
1089                                 if ((server_id != NONE) &&
1090                                     (b->server_ip != server_id))
1091                                         b->server_ip = ic_servaddr;
1092                                 break;
1093
1094                         case DHCPACK:
1095                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1096                                         goto drop_unlock;
1097
1098                                 /* Yeah! */
1099                                 break;
1100
1101                         default:
1102                                 /* Urque.  Forget it*/
1103                                 ic_myaddr = NONE;
1104                                 ic_servaddr = NONE;
1105                                 goto drop_unlock;
1106                         }
1107
1108                         ic_dhcp_msgtype = mt;
1109
1110                 }
1111 #endif /* IPCONFIG_DHCP */
1112
1113                 ext = &b->exten[4];
1114                 while (ext < end && *ext != 0xff) {
1115                         u8 *opt = ext++;
1116                         if (*opt == 0)  /* Padding */
1117                                 continue;
1118                         ext += *ext + 1;
1119                         if (ext < end)
1120                                 ic_do_bootp_ext(opt);
1121                 }
1122         }
1123
1124         /* We have a winner! */
1125         ic_dev = d;
1126         ic_myaddr = b->your_ip;
1127         ic_servaddr = b->server_ip;
1128         ic_addrservaddr = b->iph.saddr;
1129         if (ic_gateway == NONE && b->relay_ip)
1130                 ic_gateway = b->relay_ip;
1131         if (ic_nameservers[0] == NONE)
1132                 ic_nameservers[0] = ic_servaddr;
1133         ic_got_reply = IC_BOOTP;
1134
1135 drop_unlock:
1136         /* Show's over.  Nothing to see here.  */
1137         spin_unlock(&ic_recv_lock);
1138
1139 drop:
1140         /* Throw the packet out. */
1141         kfree_skb(skb);
1142
1143         return 0;
1144 }
1145
1146
1147 #endif
1148
1149
1150 /*
1151  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1152  */
1153
1154 #ifdef IPCONFIG_DYNAMIC
1155
1156 static int __init ic_dynamic(void)
1157 {
1158         int retries;
1159         struct ic_device *d;
1160         unsigned long start_jiffies, timeout, jiff;
1161         int do_bootp = ic_proto_have_if & IC_BOOTP;
1162         int do_rarp = ic_proto_have_if & IC_RARP;
1163
1164         /*
1165          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1166          * This routine gets only called when some pieces of information
1167          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1168          */
1169         if (!ic_proto_enabled) {
1170                 pr_err("IP-Config: Incomplete network configuration information\n");
1171                 return -1;
1172         }
1173
1174 #ifdef IPCONFIG_BOOTP
1175         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1176                 pr_err("DHCP/BOOTP: No suitable device found\n");
1177 #endif
1178 #ifdef IPCONFIG_RARP
1179         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1180                 pr_err("RARP: No suitable device found\n");
1181 #endif
1182
1183         if (!ic_proto_have_if)
1184                 /* Error message already printed */
1185                 return -1;
1186
1187         /*
1188          * Setup protocols
1189          */
1190 #ifdef IPCONFIG_BOOTP
1191         if (do_bootp)
1192                 ic_bootp_init();
1193 #endif
1194 #ifdef IPCONFIG_RARP
1195         if (do_rarp)
1196                 ic_rarp_init();
1197 #endif
1198
1199         /*
1200          * Send requests and wait, until we get an answer. This loop
1201          * seems to be a terrible waste of CPU time, but actually there is
1202          * only one process running at all, so we don't need to use any
1203          * scheduler functions.
1204          * [Actually we could now, but the nothing else running note still
1205          *  applies.. - AC]
1206          */
1207         pr_notice("Sending %s%s%s requests .",
1208                   do_bootp
1209                   ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1210                   (do_bootp && do_rarp) ? " and " : "",
1211                   do_rarp ? "RARP" : "");
1212
1213         start_jiffies = jiffies;
1214         d = ic_first_dev;
1215         retries = CONF_SEND_RETRIES;
1216         get_random_bytes(&timeout, sizeof(timeout));
1217         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1218         for (;;) {
1219 #ifdef IPCONFIG_BOOTP
1220                 if (do_bootp && (d->able & IC_BOOTP))
1221                         ic_bootp_send_if(d, jiffies - start_jiffies);
1222 #endif
1223 #ifdef IPCONFIG_RARP
1224                 if (do_rarp && (d->able & IC_RARP))
1225                         ic_rarp_send_if(d);
1226 #endif
1227
1228                 if (!d->next) {
1229                         jiff = jiffies + timeout;
1230                         while (time_before(jiffies, jiff) && !ic_got_reply)
1231                                 schedule_timeout_uninterruptible(1);
1232                 }
1233 #ifdef IPCONFIG_DHCP
1234                 /* DHCP isn't done until we get a DHCPACK. */
1235                 if ((ic_got_reply & IC_BOOTP) &&
1236                     (ic_proto_enabled & IC_USE_DHCP) &&
1237                     ic_dhcp_msgtype != DHCPACK) {
1238                         ic_got_reply = 0;
1239                         /* continue on device that got the reply */
1240                         d = ic_dev;
1241                         pr_cont(",");
1242                         continue;
1243                 }
1244 #endif /* IPCONFIG_DHCP */
1245
1246                 if (ic_got_reply) {
1247                         pr_cont(" OK\n");
1248                         break;
1249                 }
1250
1251                 if ((d = d->next))
1252                         continue;
1253
1254                 if (! --retries) {
1255                         pr_cont(" timed out!\n");
1256                         break;
1257                 }
1258
1259                 d = ic_first_dev;
1260
1261                 timeout = timeout CONF_TIMEOUT_MULT;
1262                 if (timeout > CONF_TIMEOUT_MAX)
1263                         timeout = CONF_TIMEOUT_MAX;
1264
1265                 pr_cont(".");
1266         }
1267
1268 #ifdef IPCONFIG_BOOTP
1269         if (do_bootp)
1270                 ic_bootp_cleanup();
1271 #endif
1272 #ifdef IPCONFIG_RARP
1273         if (do_rarp)
1274                 ic_rarp_cleanup();
1275 #endif
1276
1277         if (!ic_got_reply) {
1278                 ic_myaddr = NONE;
1279                 return -1;
1280         }
1281
1282         pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1283                 ((ic_got_reply & IC_RARP) ? "RARP"
1284                 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1285                 &ic_addrservaddr, &ic_myaddr);
1286
1287         return 0;
1288 }
1289
1290 #endif /* IPCONFIG_DYNAMIC */
1291
1292 #ifdef CONFIG_PROC_FS
1293
1294 static int pnp_seq_show(struct seq_file *seq, void *v)
1295 {
1296         int i;
1297
1298         if (ic_proto_used & IC_PROTO)
1299                 seq_printf(seq, "#PROTO: %s\n",
1300                            (ic_proto_used & IC_RARP) ? "RARP"
1301                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1302         else
1303                 seq_puts(seq, "#MANUAL\n");
1304
1305         if (ic_domain[0])
1306                 seq_printf(seq,
1307                            "domain %s\n", ic_domain);
1308         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1309                 if (ic_nameservers[i] != NONE)
1310                         seq_printf(seq, "nameserver %pI4\n",
1311                                    &ic_nameservers[i]);
1312         }
1313         if (ic_servaddr != NONE)
1314                 seq_printf(seq, "bootserver %pI4\n",
1315                            &ic_servaddr);
1316         return 0;
1317 }
1318
1319 static int pnp_seq_open(struct inode *indoe, struct file *file)
1320 {
1321         return single_open(file, pnp_seq_show, NULL);
1322 }
1323
1324 static const struct file_operations pnp_seq_fops = {
1325         .owner          = THIS_MODULE,
1326         .open           = pnp_seq_open,
1327         .read           = seq_read,
1328         .llseek         = seq_lseek,
1329         .release        = single_release,
1330 };
1331 #endif /* CONFIG_PROC_FS */
1332
1333 /*
1334  *  Extract IP address from the parameter string if needed. Note that we
1335  *  need to have root_server_addr set _before_ IPConfig gets called as it
1336  *  can override it.
1337  */
1338 __be32 __init root_nfs_parse_addr(char *name)
1339 {
1340         __be32 addr;
1341         int octets = 0;
1342         char *cp, *cq;
1343
1344         cp = cq = name;
1345         while (octets < 4) {
1346                 while (*cp >= '0' && *cp <= '9')
1347                         cp++;
1348                 if (cp == cq || cp - cq > 3)
1349                         break;
1350                 if (*cp == '.' || octets == 3)
1351                         octets++;
1352                 if (octets < 4)
1353                         cp++;
1354                 cq = cp;
1355         }
1356         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1357                 if (*cp == ':')
1358                         *cp++ = '\0';
1359                 addr = in_aton(name);
1360                 memmove(name, cp, strlen(cp) + 1);
1361         } else
1362                 addr = NONE;
1363
1364         return addr;
1365 }
1366
1367 #define DEVICE_WAIT_MAX         12 /* 12 seconds */
1368
1369 static int __init wait_for_devices(void)
1370 {
1371         int i;
1372
1373         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1374                 struct net_device *dev;
1375                 int found = 0;
1376
1377                 rtnl_lock();
1378                 for_each_netdev(&init_net, dev) {
1379                         if (ic_is_init_dev(dev)) {
1380                                 found = 1;
1381                                 break;
1382                         }
1383                 }
1384                 rtnl_unlock();
1385                 if (found)
1386                         return 0;
1387                 ssleep(1);
1388         }
1389         return -ENODEV;
1390 }
1391
1392 /*
1393  *      IP Autoconfig dispatcher.
1394  */
1395
1396 static int __init ip_auto_config(void)
1397 {
1398         __be32 addr;
1399 #ifdef IPCONFIG_DYNAMIC
1400         int retries = CONF_OPEN_RETRIES;
1401 #endif
1402         int err;
1403         unsigned int i;
1404
1405 #ifdef CONFIG_PROC_FS
1406         proc_create("pnp", S_IRUGO, init_net.proc_net, &pnp_seq_fops);
1407 #endif /* CONFIG_PROC_FS */
1408
1409         if (!ic_enable)
1410                 return 0;
1411
1412         pr_debug("IP-Config: Entered.\n");
1413 #ifdef IPCONFIG_DYNAMIC
1414  try_try_again:
1415 #endif
1416         /* Wait for devices to appear */
1417         err = wait_for_devices();
1418         if (err)
1419                 return err;
1420
1421         /* Setup all network devices */
1422         err = ic_open_devs();
1423         if (err)
1424                 return err;
1425
1426         /* Give drivers a chance to settle */
1427         msleep(CONF_POST_OPEN);
1428
1429         /*
1430          * If the config information is insufficient (e.g., our IP address or
1431          * IP address of the boot server is missing or we have multiple network
1432          * interfaces and no default was set), use BOOTP or RARP to get the
1433          * missing values.
1434          */
1435         if (ic_myaddr == NONE ||
1436 #ifdef CONFIG_ROOT_NFS
1437             (root_server_addr == NONE &&
1438              ic_servaddr == NONE &&
1439              ROOT_DEV == Root_NFS) ||
1440 #endif
1441             ic_first_dev->next) {
1442 #ifdef IPCONFIG_DYNAMIC
1443                 if (ic_dynamic() < 0) {
1444                         ic_close_devs();
1445
1446                         /*
1447                          * I don't know why, but sometimes the
1448                          * eepro100 driver (at least) gets upset and
1449                          * doesn't work the first time it's opened.
1450                          * But then if you close it and reopen it, it
1451                          * works just fine.  So we need to try that at
1452                          * least once before giving up.
1453                          *
1454                          * Also, if the root will be NFS-mounted, we
1455                          * have nowhere to go if DHCP fails.  So we
1456                          * just have to keep trying forever.
1457                          *
1458                          *                              -- Chip
1459                          */
1460 #ifdef CONFIG_ROOT_NFS
1461                         if (ROOT_DEV ==  Root_NFS) {
1462                                 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1463                                 goto try_try_again;
1464                         }
1465 #endif
1466
1467                         if (--retries) {
1468                                 pr_err("IP-Config: Reopening network devices...\n");
1469                                 goto try_try_again;
1470                         }
1471
1472                         /* Oh, well.  At least we tried. */
1473                         pr_err("IP-Config: Auto-configuration of network failed\n");
1474                         return -1;
1475                 }
1476 #else /* !DYNAMIC */
1477                 pr_err("IP-Config: Incomplete network configuration information\n");
1478                 ic_close_devs();
1479                 return -1;
1480 #endif /* IPCONFIG_DYNAMIC */
1481         } else {
1482                 /* Device selected manually or only one device -> use it */
1483                 ic_dev = ic_first_dev;
1484         }
1485
1486         addr = root_nfs_parse_addr(root_server_path);
1487         if (root_server_addr == NONE)
1488                 root_server_addr = addr;
1489
1490         /*
1491          * Use defaults wherever applicable.
1492          */
1493         if (ic_defaults() < 0)
1494                 return -1;
1495
1496         /*
1497          * Record which protocol was actually used.
1498          */
1499 #ifdef IPCONFIG_DYNAMIC
1500         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1501 #endif
1502
1503 #ifndef IPCONFIG_SILENT
1504         /*
1505          * Clue in the operator.
1506          */
1507         pr_info("IP-Config: Complete:\n");
1508
1509         pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1510                 ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1511                 &ic_myaddr, &ic_netmask, &ic_gateway);
1512         pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1513                 utsname()->nodename, ic_domain, utsname()->domainname);
1514         pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1515                 &ic_servaddr, &root_server_addr, root_server_path);
1516         if (ic_dev_mtu)
1517                 pr_cont(", mtu=%d", ic_dev_mtu);
1518         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
1519                 if (ic_nameservers[i] != NONE) {
1520                         pr_cont("     nameserver%u=%pI4",
1521                                 i, &ic_nameservers[i]);
1522                         break;
1523                 }
1524         for (i++; i < CONF_NAMESERVERS_MAX; i++)
1525                 if (ic_nameservers[i] != NONE)
1526                         pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
1527         pr_cont("\n");
1528 #endif /* !SILENT */
1529
1530         /*
1531          * Close all network devices except the device we've
1532          * autoconfigured and set up routes.
1533          */
1534         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1535                 err = -1;
1536         else
1537                 err = 0;
1538
1539         ic_close_devs();
1540
1541         return err;
1542 }
1543
1544 late_initcall(ip_auto_config);
1545
1546
1547 /*
1548  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1549  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1550  */
1551 static int __init ic_proto_name(char *name)
1552 {
1553         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1554                 return 1;
1555         }
1556         if (!strcmp(name, "off") || !strcmp(name, "none")) {
1557                 return 0;
1558         }
1559 #ifdef CONFIG_IP_PNP_DHCP
1560         else if (!strncmp(name, "dhcp", 4)) {
1561                 char *client_id;
1562
1563                 ic_proto_enabled &= ~IC_RARP;
1564                 client_id = strstr(name, "dhcp,");
1565                 if (client_id) {
1566                         char *v;
1567
1568                         client_id = client_id + 5;
1569                         v = strchr(client_id, ',');
1570                         if (!v)
1571                                 return 1;
1572                         *v = 0;
1573                         if (kstrtou8(client_id, 0, dhcp_client_identifier))
1574                                 pr_debug("DHCP: Invalid client identifier type\n");
1575                         strncpy(dhcp_client_identifier + 1, v + 1, 251);
1576                         *v = ',';
1577                 }
1578                 return 1;
1579         }
1580 #endif
1581 #ifdef CONFIG_IP_PNP_BOOTP
1582         else if (!strcmp(name, "bootp")) {
1583                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1584                 return 1;
1585         }
1586 #endif
1587 #ifdef CONFIG_IP_PNP_RARP
1588         else if (!strcmp(name, "rarp")) {
1589                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1590                 return 1;
1591         }
1592 #endif
1593 #ifdef IPCONFIG_DYNAMIC
1594         else if (!strcmp(name, "both")) {
1595                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1596                 return 1;
1597         }
1598 #endif
1599         return 0;
1600 }
1601
1602 static int __init ip_auto_config_setup(char *addrs)
1603 {
1604         char *cp, *ip, *dp;
1605         int num = 0;
1606
1607         ic_set_manually = 1;
1608         ic_enable = 1;
1609
1610         /*
1611          * If any dhcp, bootp etc options are set, leave autoconfig on
1612          * and skip the below static IP processing.
1613          */
1614         if (ic_proto_name(addrs))
1615                 return 1;
1616
1617         /* If no static IP is given, turn off autoconfig and bail.  */
1618         if (*addrs == 0 ||
1619             strcmp(addrs, "off") == 0 ||
1620             strcmp(addrs, "none") == 0) {
1621                 ic_enable = 0;
1622                 return 1;
1623         }
1624
1625         ic_nameservers_predef();
1626
1627         /* Parse string for static IP assignment.  */
1628         ip = addrs;
1629         while (ip && *ip) {
1630                 if ((cp = strchr(ip, ':')))
1631                         *cp++ = '\0';
1632                 if (strlen(ip) > 0) {
1633                         pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1634                         switch (num) {
1635                         case 0:
1636                                 if ((ic_myaddr = in_aton(ip)) == ANY)
1637                                         ic_myaddr = NONE;
1638                                 break;
1639                         case 1:
1640                                 if ((ic_servaddr = in_aton(ip)) == ANY)
1641                                         ic_servaddr = NONE;
1642                                 break;
1643                         case 2:
1644                                 if ((ic_gateway = in_aton(ip)) == ANY)
1645                                         ic_gateway = NONE;
1646                                 break;
1647                         case 3:
1648                                 if ((ic_netmask = in_aton(ip)) == ANY)
1649                                         ic_netmask = NONE;
1650                                 break;
1651                         case 4:
1652                                 if ((dp = strchr(ip, '.'))) {
1653                                         *dp++ = '\0';
1654                                         strlcpy(utsname()->domainname, dp,
1655                                                 sizeof(utsname()->domainname));
1656                                 }
1657                                 strlcpy(utsname()->nodename, ip,
1658                                         sizeof(utsname()->nodename));
1659                                 ic_host_name_set = 1;
1660                                 break;
1661                         case 5:
1662                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1663                                 break;
1664                         case 6:
1665                                 if (ic_proto_name(ip) == 0 &&
1666                                     ic_myaddr == NONE) {
1667                                         ic_enable = 0;
1668                                 }
1669                                 break;
1670                         case 7:
1671                                 if (CONF_NAMESERVERS_MAX >= 1) {
1672                                         ic_nameservers[0] = in_aton(ip);
1673                                         if (ic_nameservers[0] == ANY)
1674                                                 ic_nameservers[0] = NONE;
1675                                 }
1676                                 break;
1677                         case 8:
1678                                 if (CONF_NAMESERVERS_MAX >= 2) {
1679                                         ic_nameservers[1] = in_aton(ip);
1680                                         if (ic_nameservers[1] == ANY)
1681                                                 ic_nameservers[1] = NONE;
1682                                 }
1683                                 break;
1684                         }
1685                 }
1686                 ip = cp;
1687                 num++;
1688         }
1689
1690         return 1;
1691 }
1692 __setup("ip=", ip_auto_config_setup);
1693
1694 static int __init nfsaddrs_config_setup(char *addrs)
1695 {
1696         return ip_auto_config_setup(addrs);
1697 }
1698 __setup("nfsaddrs=", nfsaddrs_config_setup);
1699
1700 static int __init vendor_class_identifier_setup(char *addrs)
1701 {
1702         if (strlcpy(vendor_class_identifier, addrs,
1703                     sizeof(vendor_class_identifier))
1704             >= sizeof(vendor_class_identifier))
1705                 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1706                         vendor_class_identifier);
1707         return 1;
1708 }
1709 __setup("dhcpclass=", vendor_class_identifier_setup);