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