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 <mj@atrey.karlin.mff.cuni.cz>
   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 <acme@conectiva.com.br>, 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 <chip@valinux.com>, May 2000
  22  *
  23  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
  24  *              -- Eric Biederman <ebiederman@lnxi.com>, 30 Aug 2000
  25  *
  26  *  Merged changes from 2.2.19 into 2.4.3
  27  *              -- Eric Biederman <ebiederman@lnxi.com>, 22 April Aug 2001
  28  *
  29  *  Multiple Nameservers in /proc/net/pnp
  30  *              --  Josef Siemes <jsiemes@web.de>, Aug 2002
  31  *
  32  *  NTP servers in /proc/net/ipconfig/ntp_servers
  33  *              --  Chris Novakovic <chris@chrisn.me.uk>, April 2018
  34  */
  35
  36 #include <linux/types.h>
  37 #include <linux/string.h>
  38 #include <linux/kernel.h>
  39 #include <linux/jiffies.h>
  40 #include <linux/random.h>
  41 #include <linux/init.h>
  42 #include <linux/utsname.h>
  43 #include <linux/in.h>
  44 #include <linux/if.h>
  45 #include <linux/inet.h>
  46 #include <linux/inetdevice.h>
  47 #include <linux/netdevice.h>
  48 #include <linux/if_arp.h>
  49 #include <linux/skbuff.h>
  50 #include <linux/ip.h>
  51 #include <linux/socket.h>
  52 #include <linux/route.h>
  53 #include <linux/udp.h>
  54 #include <linux/proc_fs.h>
  55 #include <linux/seq_file.h>
  56 #include <linux/major.h>
  57 #include <linux/root_dev.h>
  58 #include <linux/delay.h>
  59 #include <linux/nfs_fs.h>
  60 #include <linux/slab.h>
  61 #include <linux/export.h>
  62 #include <net/net_namespace.h>
  63 #include <net/arp.h>
  64 #include <net/dsa.h>
  65 #include <net/ip.h>
  66 #include <net/ipconfig.h>
  67 #include <net/route.h>
  68
  69 #include <linux/uaccess.h>
  70 #include <net/checksum.h>
  71 #include <asm/processor.h>
  72
  73 #if defined(CONFIG_IP_PNP_DHCP)
  74 #define IPCONFIG_DHCP
  75 #endif
  76 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
  77 #define IPCONFIG_BOOTP
  78 #endif
  79 #if defined(CONFIG_IP_PNP_RARP)
  80 #define IPCONFIG_RARP
  81 #endif
  82 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
  83 #define IPCONFIG_DYNAMIC
  84 #endif
  85
  86 /* Define the friendly delay before and after opening net devices */
  87 #define CONF_POST_OPEN          10      /* After opening: 10 msecs */
  88 #define CONF_CARRIER_TIMEOUT    120000  /* Wait for carrier timeout */
  89
  90 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
  91 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
  92 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
  93 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
  94 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
  95 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
  96 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
  97 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
  98                                            - '3' from resolv.h */
  99 #define CONF_NTP_SERVERS_MAX   3        /* Maximum number of NTP servers */
 100
 101 #define NONE cpu_to_be32(INADDR_NONE)
 102 #define ANY cpu_to_be32(INADDR_ANY)
 103
 104 /*
 105  * Public IP configuration
 106  */
 107
 108 /* This is used by platforms which might be able to set the ipconfig
 109  * variables using firmware environment vars.  If this is set, it will
 110  * ignore such firmware variables.
 111  */
 112 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
 113
 114 static int ic_enable __initdata;                /* IP config enabled? */
 115
 116 /* Protocol choice */
 117 int ic_proto_enabled __initdata = 0
 118 #ifdef IPCONFIG_BOOTP
 119                         | IC_BOOTP
 120 #endif
 121 #ifdef CONFIG_IP_PNP_DHCP
 122                         | IC_USE_DHCP
 123 #endif
 124 #ifdef IPCONFIG_RARP
 125                         | IC_RARP
 126 #endif
 127                         ;
 128
 129 static int ic_host_name_set __initdata; /* Host name set by us? */
 130
 131 __be32 ic_myaddr = NONE;                /* My IP address */
 132 static __be32 ic_netmask = NONE;        /* Netmask for local subnet */
 133 __be32 ic_gateway = NONE;       /* Gateway IP address */
 134
 135 #ifdef IPCONFIG_DYNAMIC
 136 static __be32 ic_addrservaddr = NONE;   /* IP Address of the IP addresses'server */
 137 #endif
 138
 139 __be32 ic_servaddr = NONE;      /* Boot server IP address */
 140
 141 __be32 root_server_addr = NONE; /* Address of NFS server */
 142 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
 143
 144 /* vendor class identifier */
 145 static char vendor_class_identifier[253] __initdata;
 146
 147 #if defined(CONFIG_IP_PNP_DHCP)
 148 static char dhcp_client_identifier[253] __initdata;
 149 #endif
 150
 151 /* Persistent data: */
 152
 153 #ifdef IPCONFIG_DYNAMIC
 154 static int ic_proto_used;                       /* Protocol used, if any */
 155 #else
 156 #define ic_proto_used 0
 157 #endif
 158 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
 159 static __be32 ic_ntp_servers[CONF_NTP_SERVERS_MAX]; /* NTP server IP addresses */
 160 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
 161
 162 /*
 163  * Private state.
 164  */
 165
 166 /* Name of user-selected boot device */
 167 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 168
 169 /* Protocols supported by available interfaces */
 170 static int ic_proto_have_if __initdata;
 171
 172 /* MTU for boot device */
 173 static int ic_dev_mtu __initdata;
 174
 175 #ifdef IPCONFIG_DYNAMIC
 176 static DEFINE_SPINLOCK(ic_recv_lock);
 177 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
 178 #endif
 179 #ifdef IPCONFIG_DHCP
 180 static int ic_dhcp_msgtype __initdata;  /* DHCP msg type received */
 181 #endif
 182
 183
 184 /*
 185  *      Network devices
 186  */
 187
 188 struct ic_device {
 189         struct ic_device *next;
 190         struct net_device *dev;
 191         unsigned short flags;
 192         short able;
 193         __be32 xid;
 194 };
 195
 196 static struct ic_device *ic_first_dev __initdata;       /* List of open device */
 197 static struct ic_device *ic_dev __initdata;             /* Selected device */
 198
 199 static bool __init ic_is_init_dev(struct net_device *dev)
 200 {
 201         if (dev->flags & IFF_LOOPBACK)
 202                 return false;
 203         return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 204             (!(dev->flags & IFF_LOOPBACK) &&
 205              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 206              strncmp(dev->name, "dummy", 5));
 207 }
 208
 209 static int __init ic_open_devs(void)
 210 {
 211         struct ic_device *d, **last;
 212         struct net_device *dev;
 213         unsigned short oflags;
 214         unsigned long start, next_msg;
 215
 216         last = &ic_first_dev;
 217         rtnl_lock();
 218
 219         /* bring loopback and DSA master network devices up first */
 220         for_each_netdev(&init_net, dev) {
 221                 if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
 222                         continue;
 223                 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
 224                         pr_err("IP-Config: Failed to open %s\n", dev->name);
 225         }
 226
 227         for_each_netdev(&init_net, dev) {
 228                 if (ic_is_init_dev(dev)) {
 229                         int able = 0;
 230                         if (dev->mtu >= 364)
 231                                 able |= IC_BOOTP;
 232                         else
 233                                 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
 234                                         dev->name, dev->mtu);
 235                         if (!(dev->flags & IFF_NOARP))
 236                                 able |= IC_RARP;
 237                         able &= ic_proto_enabled;
 238                         if (ic_proto_enabled && !able)
 239                                 continue;
 240                         oflags = dev->flags;
 241                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
 242                                 pr_err("IP-Config: Failed to open %s\n",
 243                                        dev->name);
 244                                 continue;
 245                         }
 246                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 247                                 rtnl_unlock();
 248                                 return -ENOMEM;
 249                         }
 250                         d->dev = dev;
 251                         *last = d;
 252                         last = &d->next;
 253                         d->flags = oflags;
 254                         d->able = able;
 255                         if (able & IC_BOOTP)
 256                                 get_random_bytes(&d->xid, sizeof(__be32));
 257                         else
 258                                 d->xid = 0;
 259                         ic_proto_have_if |= able;
 260                         pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
 261                                  dev->name, able, d->xid);
 262                 }
 263         }
 264
 265         /* no point in waiting if we could not bring up at least one device */
 266         if (!ic_first_dev)
 267                 goto have_carrier;
 268
 269         /* wait for a carrier on at least one device */
 270         start = jiffies;
 271         next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
 272         while (time_before(jiffies, start +
 273                            msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
 274                 int wait, elapsed;
 275
 276                 for_each_netdev(&init_net, dev)
 277                         if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
 278                                 goto have_carrier;
 279
 280                 msleep(1);
 281
 282                 if (time_before(jiffies, next_msg))
 283                         continue;
 284
 285                 elapsed = jiffies_to_msecs(jiffies - start);
 286                 wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
 287                 pr_info("Waiting up to %d more seconds for network.\n", wait);
 288                 next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
 289         }
 290 have_carrier:
 291         rtnl_unlock();
 292
 293         *last = NULL;
 294
 295         if (!ic_first_dev) {
 296                 if (user_dev_name[0])
 297                         pr_err("IP-Config: Device `%s' not found\n",
 298                                user_dev_name);
 299                 else
 300                         pr_err("IP-Config: No network devices available\n");
 301                 return -ENODEV;
 302         }
 303         return 0;
 304 }
 305
 306 static void __init ic_close_devs(void)
 307 {
 308         struct ic_device *d, *next;
 309         struct net_device *dev;
 310
 311         rtnl_lock();
 312         next = ic_first_dev;
 313         while ((d = next)) {
 314                 next = d->next;
 315                 dev = d->dev;
 316                 if (d != ic_dev && !netdev_uses_dsa(dev)) {
 317                         pr_debug("IP-Config: Downing %s\n", dev->name);
 318                         dev_change_flags(dev, d->flags);
 319                 }
 320                 kfree(d);
 321         }
 322         rtnl_unlock();
 323 }
 324
 325 /*
 326  *      Interface to various network functions.
 327  */
 328
 329 static inline void
 330 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
 331 {
 332         sin->sin_family = AF_INET;
 333         sin->sin_addr.s_addr = addr;
 334         sin->sin_port = port;
 335 }
 336
 337 /*
 338  *      Set up interface addresses and routes.
 339  */
 340
 341 static int __init ic_setup_if(void)
 342 {
 343         struct ifreq ir;
 344         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 345         int err;
 346
 347         memset(&ir, 0, sizeof(ir));
 348         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
 349         set_sockaddr(sin, ic_myaddr, 0);
 350         if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) {
 351                 pr_err("IP-Config: Unable to set interface address (%d)\n",
 352                        err);
 353                 return -1;
 354         }
 355         set_sockaddr(sin, ic_netmask, 0);
 356         if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) {
 357                 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
 358                        err);
 359                 return -1;
 360         }
 361         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 362         if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) {
 363                 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
 364                        err);
 365                 return -1;
 366         }
 367         /* Handle the case where we need non-standard MTU on the boot link (a network
 368          * using jumbo frames, for instance).  If we can't set the mtu, don't error
 369          * out, we'll try to muddle along.
 370          */
 371         if (ic_dev_mtu != 0) {
 372                 rtnl_lock();
 373                 if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0)
 374                         pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
 375                                ic_dev_mtu, err);
 376                 rtnl_unlock();
 377         }
 378         return 0;
 379 }
 380
 381 static int __init ic_setup_routes(void)
 382 {
 383         /* No need to setup device routes, only the default route... */
 384
 385         if (ic_gateway != NONE) {
 386                 struct rtentry rm;
 387                 int err;
 388
 389                 memset(&rm, 0, sizeof(rm));
 390                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 391                         pr_err("IP-Config: Gateway not on directly connected network\n");
 392                         return -1;
 393                 }
 394                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 395                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 396                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 397                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 398                 if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) {
 399                         pr_err("IP-Config: Cannot add default route (%d)\n",
 400                                err);
 401                         return -1;
 402                 }
 403         }
 404
 405         return 0;
 406 }
 407
 408 /*
 409  *      Fill in default values for all missing parameters.
 410  */
 411
 412 static int __init ic_defaults(void)
 413 {
 414         /*
 415          *      At this point we have no userspace running so need not
 416          *      claim locks on system_utsname
 417          */
 418
 419         if (!ic_host_name_set)
 420                 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
 421
 422         if (root_server_addr == NONE)
 423                 root_server_addr = ic_servaddr;
 424
 425         if (ic_netmask == NONE) {
 426                 if (IN_CLASSA(ntohl(ic_myaddr)))
 427                         ic_netmask = htonl(IN_CLASSA_NET);
 428                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 429                         ic_netmask = htonl(IN_CLASSB_NET);
 430                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 431                         ic_netmask = htonl(IN_CLASSC_NET);
 432                 else {
 433                         pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
 434                                &ic_myaddr);
 435                         return -1;
 436                 }
 437                 pr_notice("IP-Config: Guessing netmask %pI4\n",
 438                           &ic_netmask);
 439         }
 440
 441         return 0;
 442 }
 443
 444 /*
 445  *      RARP support.
 446  */
 447
 448 #ifdef IPCONFIG_RARP
 449
 450 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 451
 452 static struct packet_type rarp_packet_type __initdata = {
 453         .type = cpu_to_be16(ETH_P_RARP),
 454         .func = ic_rarp_recv,
 455 };
 456
 457 static inline void __init ic_rarp_init(void)
 458 {
 459         dev_add_pack(&rarp_packet_type);
 460 }
 461
 462 static inline void __init ic_rarp_cleanup(void)
 463 {
 464         dev_remove_pack(&rarp_packet_type);
 465 }
 466
 467 /*
 468  *  Process received RARP packet.
 469  */
 470 static int __init
 471 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 472 {
 473         struct arphdr *rarp;
 474         unsigned char *rarp_ptr;
 475         __be32 sip, tip;
 476         unsigned char *tha;             /* t for "target" */
 477         struct ic_device *d;
 478
 479         if (!net_eq(dev_net(dev), &init_net))
 480                 goto drop;
 481
 482         skb = skb_share_check(skb, GFP_ATOMIC);
 483         if (!skb)
 484                 return NET_RX_DROP;
 485
 486         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 487                 goto drop;
 488
 489         /* Basic sanity checks can be done without the lock.  */
 490         rarp = (struct arphdr *)skb_transport_header(skb);
 491
 492         /* If this test doesn't pass, it's not IP, or we should
 493          * ignore it anyway.
 494          */
 495         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 496                 goto drop;
 497
 498         /* If it's not a RARP reply, delete it. */
 499         if (rarp->ar_op != htons(ARPOP_RREPLY))
 500                 goto drop;
 501
 502         /* If it's not Ethernet, delete it. */
 503         if (rarp->ar_pro != htons(ETH_P_IP))
 504                 goto drop;
 505
 506         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
 507                 goto drop;
 508
 509         /* OK, it is all there and looks valid, process... */
 510         rarp = (struct arphdr *)skb_transport_header(skb);
 511         rarp_ptr = (unsigned char *) (rarp + 1);
 512
 513         /* One reply at a time, please. */
 514         spin_lock(&ic_recv_lock);
 515
 516         /* If we already have a reply, just drop the packet */
 517         if (ic_got_reply)
 518                 goto drop_unlock;
 519
 520         /* Find the ic_device that the packet arrived on */
 521         d = ic_first_dev;
 522         while (d && d->dev != dev)
 523                 d = d->next;
 524         if (!d)
 525                 goto drop_unlock;       /* should never happen */
 526
 527         /* Extract variable-width fields */
 528         rarp_ptr += dev->addr_len;
 529         memcpy(&sip, rarp_ptr, 4);
 530         rarp_ptr += 4;
 531         tha = rarp_ptr;
 532         rarp_ptr += dev->addr_len;
 533         memcpy(&tip, rarp_ptr, 4);
 534
 535         /* Discard packets which are not meant for us. */
 536         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 537                 goto drop_unlock;
 538
 539         /* Discard packets which are not from specified server. */
 540         if (ic_servaddr != NONE && ic_servaddr != sip)
 541                 goto drop_unlock;
 542
 543         /* We have a winner! */
 544         ic_dev = d;
 545         if (ic_myaddr == NONE)
 546                 ic_myaddr = tip;
 547         ic_servaddr = sip;
 548         ic_addrservaddr = sip;
 549         ic_got_reply = IC_RARP;
 550
 551 drop_unlock:
 552         /* Show's over.  Nothing to see here.  */
 553         spin_unlock(&ic_recv_lock);
 554
 555 drop:
 556         /* Throw the packet out. */
 557         kfree_skb(skb);
 558         return 0;
 559 }
 560
 561
 562 /*
 563  *  Send RARP request packet over a single interface.
 564  */
 565 static void __init ic_rarp_send_if(struct ic_device *d)
 566 {
 567         struct net_device *dev = d->dev;
 568         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 569                  dev->dev_addr, dev->dev_addr);
 570 }
 571 #endif
 572
 573 /*
 574  *  Predefine Nameservers
 575  */
 576 static inline void __init ic_nameservers_predef(void)
 577 {
 578         int i;
 579
 580         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 581                 ic_nameservers[i] = NONE;
 582 }
 583
 584 /* Predefine NTP servers */
 585 static inline void __init ic_ntp_servers_predef(void)
 586 {
 587         int i;
 588
 589         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++)
 590                 ic_ntp_servers[i] = NONE;
 591 }
 592
 593 /*
 594  *      DHCP/BOOTP support.
 595  */
 596
 597 #ifdef IPCONFIG_BOOTP
 598
 599 struct bootp_pkt {              /* BOOTP packet format */
 600         struct iphdr iph;       /* IP header */
 601         struct udphdr udph;     /* UDP header */
 602         u8 op;                  /* 1=request, 2=reply */
 603         u8 htype;               /* HW address type */
 604         u8 hlen;                /* HW address length */
 605         u8 hops;                /* Used only by gateways */
 606         __be32 xid;             /* Transaction ID */
 607         __be16 secs;            /* Seconds since we started */
 608         __be16 flags;           /* Just what it says */
 609         __be32 client_ip;               /* Client's IP address if known */
 610         __be32 your_ip;         /* Assigned IP address */
 611         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
 612         __be32 relay_ip;                /* IP address of BOOTP relay */
 613         u8 hw_addr[16];         /* Client's HW address */
 614         u8 serv_name[64];       /* Server host name */
 615         u8 boot_file[128];      /* Name of boot file */
 616         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 617 };
 618
 619 /* packet ops */
 620 #define BOOTP_REQUEST   1
 621 #define BOOTP_REPLY     2
 622
 623 /* DHCP message types */
 624 #define DHCPDISCOVER    1
 625 #define DHCPOFFER       2
 626 #define DHCPREQUEST     3
 627 #define DHCPDECLINE     4
 628 #define DHCPACK         5
 629 #define DHCPNAK         6
 630 #define DHCPRELEASE     7
 631 #define DHCPINFORM      8
 632
 633 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 634
 635 static struct packet_type bootp_packet_type __initdata = {
 636         .type = cpu_to_be16(ETH_P_IP),
 637         .func = ic_bootp_recv,
 638 };
 639
 640 /*
 641  *  Initialize DHCP/BOOTP extension fields in the request.
 642  */
 643
 644 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 645
 646 #ifdef IPCONFIG_DHCP
 647
 648 static void __init
 649 ic_dhcp_init_options(u8 *options, struct ic_device *d)
 650 {
 651         u8 mt = ((ic_servaddr == NONE)
 652                  ? DHCPDISCOVER : DHCPREQUEST);
 653         u8 *e = options;
 654         int len;
 655
 656         pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
 657
 658         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 659         e += 4;
 660
 661         *e++ = 53;              /* DHCP message type */
 662         *e++ = 1;
 663         *e++ = mt;
 664
 665         if (mt == DHCPREQUEST) {
 666                 *e++ = 54;      /* Server ID (IP address) */
 667                 *e++ = 4;
 668                 memcpy(e, &ic_servaddr, 4);
 669                 e += 4;
 670
 671                 *e++ = 50;      /* Requested IP address */
 672                 *e++ = 4;
 673                 memcpy(e, &ic_myaddr, 4);
 674                 e += 4;
 675         }
 676
 677         /* always? */
 678         {
 679                 static const u8 ic_req_params[] = {
 680                         1,      /* Subnet mask */
 681                         3,      /* Default gateway */
 682                         6,      /* DNS server */
 683                         12,     /* Host name */
 684                         15,     /* Domain name */
 685                         17,     /* Boot path */
 686                         26,     /* MTU */
 687                         40,     /* NIS domain name */
 688                         42,     /* NTP servers */
 689                 };
 690
 691                 *e++ = 55;      /* Parameter request list */
 692                 *e++ = sizeof(ic_req_params);
 693                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 694                 e += sizeof(ic_req_params);
 695
 696                 if (ic_host_name_set) {
 697                         *e++ = 12;      /* host-name */
 698                         len = strlen(utsname()->nodename);
 699                         *e++ = len;
 700                         memcpy(e, utsname()->nodename, len);
 701                         e += len;
 702                 }
 703                 if (*vendor_class_identifier) {
 704                         pr_info("DHCP: sending class identifier \"%s\"\n",
 705                                 vendor_class_identifier);
 706                         *e++ = 60;      /* Class-identifier */
 707                         len = strlen(vendor_class_identifier);
 708                         *e++ = len;
 709                         memcpy(e, vendor_class_identifier, len);
 710                         e += len;
 711                 }
 712                 len = strlen(dhcp_client_identifier + 1);
 713                 /* the minimum length of identifier is 2, include 1 byte type,
 714                  * and can not be larger than the length of options
 715                  */
 716                 if (len >= 1 && len < 312 - (e - options) - 1) {
 717                         *e++ = 61;
 718                         *e++ = len + 1;
 719                         memcpy(e, dhcp_client_identifier, len + 1);
 720                         e += len + 1;
 721                 }
 722         }
 723
 724         *e++ = 255;     /* End of the list */
 725 }
 726
 727 #endif /* IPCONFIG_DHCP */
 728
 729 static void __init ic_bootp_init_ext(u8 *e)
 730 {
 731         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 732         e += 4;
 733         *e++ = 1;               /* Subnet mask request */
 734         *e++ = 4;
 735         e += 4;
 736         *e++ = 3;               /* Default gateway request */
 737         *e++ = 4;
 738         e += 4;
 739 #if CONF_NAMESERVERS_MAX > 0
 740         *e++ = 6;               /* (DNS) name server request */
 741         *e++ = 4 * CONF_NAMESERVERS_MAX;
 742         e += 4 * CONF_NAMESERVERS_MAX;
 743 #endif
 744         *e++ = 12;              /* Host name request */
 745         *e++ = 32;
 746         e += 32;
 747         *e++ = 40;              /* NIS Domain name request */
 748         *e++ = 32;
 749         e += 32;
 750         *e++ = 17;              /* Boot path */
 751         *e++ = 40;
 752         e += 40;
 753
 754         *e++ = 57;              /* set extension buffer size for reply */
 755         *e++ = 2;
 756         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 757         *e++ = 150;
 758
 759         *e++ = 255;             /* End of the list */
 760 }
 761
 762
 763 /*
 764  *  Initialize the DHCP/BOOTP mechanism.
 765  */
 766 static inline void __init ic_bootp_init(void)
 767 {
 768         /* Re-initialise all name servers and NTP servers to NONE, in case any
 769          * were set via the "ip=" or "nfsaddrs=" kernel command line parameters:
 770          * any IP addresses specified there will already have been decoded but
 771          * are no longer needed
 772          */
 773         ic_nameservers_predef();
 774         ic_ntp_servers_predef();
 775
 776         dev_add_pack(&bootp_packet_type);
 777 }
 778
 779
 780 /*
 781  *  DHCP/BOOTP cleanup.
 782  */
 783 static inline void __init ic_bootp_cleanup(void)
 784 {
 785         dev_remove_pack(&bootp_packet_type);
 786 }
 787
 788
 789 /*
 790  *  Send DHCP/BOOTP request to single interface.
 791  */
 792 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 793 {
 794         struct net_device *dev = d->dev;
 795         struct sk_buff *skb;
 796         struct bootp_pkt *b;
 797         struct iphdr *h;
 798         int hlen = LL_RESERVED_SPACE(dev);
 799         int tlen = dev->needed_tailroom;
 800
 801         /* Allocate packet */
 802         skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
 803                         GFP_KERNEL);
 804         if (!skb)
 805                 return;
 806         skb_reserve(skb, hlen);
 807         b = skb_put_zero(skb, sizeof(struct bootp_pkt));
 808
 809         /* Construct IP header */
 810         skb_reset_network_header(skb);
 811         h = ip_hdr(skb);
 812         h->version = 4;
 813         h->ihl = 5;
 814         h->tot_len = htons(sizeof(struct bootp_pkt));
 815         h->frag_off = htons(IP_DF);
 816         h->ttl = 64;
 817         h->protocol = IPPROTO_UDP;
 818         h->daddr = htonl(INADDR_BROADCAST);
 819         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 820
 821         /* Construct UDP header */
 822         b->udph.source = htons(68);
 823         b->udph.dest = htons(67);
 824         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 825         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 826
 827         /* Construct DHCP/BOOTP header */
 828         b->op = BOOTP_REQUEST;
 829         if (dev->type < 256) /* check for false types */
 830                 b->htype = dev->type;
 831         else if (dev->type == ARPHRD_FDDI)
 832                 b->htype = ARPHRD_ETHER;
 833         else {
 834                 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
 835                         dev->name);
 836                 b->htype = dev->type; /* can cause undefined behavior */
 837         }
 838
 839         /* server_ip and your_ip address are both already zero per RFC2131 */
 840         b->hlen = dev->addr_len;
 841         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 842         b->secs = htons(jiffies_diff / HZ);
 843         b->xid = d->xid;
 844
 845         /* add DHCP options or BOOTP extensions */
 846 #ifdef IPCONFIG_DHCP
 847         if (ic_proto_enabled & IC_USE_DHCP)
 848                 ic_dhcp_init_options(b->exten, d);
 849         else
 850 #endif
 851                 ic_bootp_init_ext(b->exten);
 852
 853         /* Chain packet down the line... */
 854         skb->dev = dev;
 855         skb->protocol = htons(ETH_P_IP);
 856         if (dev_hard_header(skb, dev, ntohs(skb->protocol),
 857                             dev->broadcast, dev->dev_addr, skb->len) < 0) {
 858                 kfree_skb(skb);
 859                 printk("E");
 860                 return;
 861         }
 862
 863         if (dev_queue_xmit(skb) < 0)
 864                 printk("E");
 865 }
 866
 867
 868 /*
 869  *  Copy BOOTP-supplied string
 870  */
 871 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 872 {
 873         if (!len)
 874                 return 0;
 875         if (len > max-1)
 876                 len = max-1;
 877         memcpy(dest, src, len);
 878         dest[len] = '\0';
 879         return 1;
 880 }
 881
 882
 883 /*
 884  *  Process BOOTP extensions.
 885  */
 886 static void __init ic_do_bootp_ext(u8 *ext)
 887 {
 888         u8 servers;
 889         int i;
 890         __be16 mtu;
 891
 892         u8 *c;
 893
 894         pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
 895         for (c=ext+2; c<ext+2+ext[1]; c++)
 896                 pr_debug(" %02x", *c);
 897         pr_debug("\n");
 898
 899         switch (*ext++) {
 900         case 1:         /* Subnet mask */
 901                 if (ic_netmask == NONE)
 902                         memcpy(&ic_netmask, ext+1, 4);
 903                 break;
 904         case 3:         /* Default gateway */
 905                 if (ic_gateway == NONE)
 906                         memcpy(&ic_gateway, ext+1, 4);
 907                 break;
 908         case 6:         /* DNS server */
 909                 servers= *ext/4;
 910                 if (servers > CONF_NAMESERVERS_MAX)
 911                         servers = CONF_NAMESERVERS_MAX;
 912                 for (i = 0; i < servers; i++) {
 913                         if (ic_nameservers[i] == NONE)
 914                                 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 915                 }
 916                 break;
 917         case 12:        /* Host name */
 918                 if (!ic_host_name_set) {
 919                         ic_bootp_string(utsname()->nodename, ext+1, *ext,
 920                                         __NEW_UTS_LEN);
 921                         ic_host_name_set = 1;
 922                 }
 923                 break;
 924         case 15:        /* Domain name (DNS) */
 925                 if (!ic_domain[0])
 926                         ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
 927                 break;
 928         case 17:        /* Root path */
 929                 if (!root_server_path[0])
 930                         ic_bootp_string(root_server_path, ext+1, *ext,
 931                                         sizeof(root_server_path));
 932                 break;
 933         case 26:        /* Interface MTU */
 934                 memcpy(&mtu, ext+1, sizeof(mtu));
 935                 ic_dev_mtu = ntohs(mtu);
 936                 break;
 937         case 40:        /* NIS Domain name (_not_ DNS) */
 938                 ic_bootp_string(utsname()->domainname, ext+1, *ext,
 939                                 __NEW_UTS_LEN);
 940                 break;
 941         case 42:        /* NTP servers */
 942                 servers = *ext / 4;
 943                 if (servers > CONF_NTP_SERVERS_MAX)
 944                         servers = CONF_NTP_SERVERS_MAX;
 945                 for (i = 0; i < servers; i++) {
 946                         if (ic_ntp_servers[i] == NONE)
 947                                 memcpy(&ic_ntp_servers[i], ext+1+4*i, 4);
 948                 }
 949                 break;
 950         }
 951 }
 952
 953
 954 /*
 955  *  Receive BOOTP reply.
 956  */
 957 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 958 {
 959         struct bootp_pkt *b;
 960         struct iphdr *h;
 961         struct ic_device *d;
 962         int len, ext_len;
 963
 964         if (!net_eq(dev_net(dev), &init_net))
 965                 goto drop;
 966
 967         /* Perform verifications before taking the lock.  */
 968         if (skb->pkt_type == PACKET_OTHERHOST)
 969                 goto drop;
 970
 971         skb = skb_share_check(skb, GFP_ATOMIC);
 972         if (!skb)
 973                 return NET_RX_DROP;
 974
 975         if (!pskb_may_pull(skb,
 976                            sizeof(struct iphdr) +
 977                            sizeof(struct udphdr)))
 978                 goto drop;
 979
 980         b = (struct bootp_pkt *)skb_network_header(skb);
 981         h = &b->iph;
 982
 983         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
 984                 goto drop;
 985
 986         /* Fragments are not supported */
 987         if (ip_is_fragment(h)) {
 988                 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
 989                 goto drop;
 990         }
 991
 992         if (skb->len < ntohs(h->tot_len))
 993                 goto drop;
 994
 995         if (ip_fast_csum((char *) h, h->ihl))
 996                 goto drop;
 997
 998         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
 999                 goto drop;
1000
1001         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1002                 goto drop;
1003
1004         len = ntohs(b->udph.len) - sizeof(struct udphdr);
1005         ext_len = len - (sizeof(*b) -
1006                          sizeof(struct iphdr) -
1007                          sizeof(struct udphdr) -
1008                          sizeof(b->exten));
1009         if (ext_len < 0)
1010                 goto drop;
1011
1012         /* Ok the front looks good, make sure we can get at the rest.  */
1013         if (!pskb_may_pull(skb, skb->len))
1014                 goto drop;
1015
1016         b = (struct bootp_pkt *)skb_network_header(skb);
1017         h = &b->iph;
1018
1019         /* One reply at a time, please. */
1020         spin_lock(&ic_recv_lock);
1021
1022         /* If we already have a reply, just drop the packet */
1023         if (ic_got_reply)
1024                 goto drop_unlock;
1025
1026         /* Find the ic_device that the packet arrived on */
1027         d = ic_first_dev;
1028         while (d && d->dev != dev)
1029                 d = d->next;
1030         if (!d)
1031                 goto drop_unlock;  /* should never happen */
1032
1033         /* Is it a reply to our BOOTP request? */
1034         if (b->op != BOOTP_REPLY ||
1035             b->xid != d->xid) {
1036                 net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1037                                     d->dev->name, b->op, b->xid);
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 (%s)\n", mt, d->dev->name);
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 = d;
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                 if (do_bootp && (d->able & IC_BOOTP))
1223                         ic_bootp_send_if(d, jiffies - start_jiffies);
1224 #endif
1225 #ifdef IPCONFIG_RARP
1226                 if (do_rarp && (d->able & IC_RARP))
1227                         ic_rarp_send_if(d);
1228 #endif
1229
1230                 if (!d->next) {
1231                         jiff = jiffies + timeout;
1232                         while (time_before(jiffies, jiff) && !ic_got_reply)
1233                                 schedule_timeout_uninterruptible(1);
1234                 }
1235 #ifdef IPCONFIG_DHCP
1236                 /* DHCP isn't done until we get a DHCPACK. */
1237                 if ((ic_got_reply & IC_BOOTP) &&
1238                     (ic_proto_enabled & IC_USE_DHCP) &&
1239                     ic_dhcp_msgtype != DHCPACK) {
1240                         ic_got_reply = 0;
1241                         /* continue on device that got the reply */
1242                         d = ic_dev;
1243                         pr_cont(",");
1244                         continue;
1245                 }
1246 #endif /* IPCONFIG_DHCP */
1247
1248                 if (ic_got_reply) {
1249                         pr_cont(" OK\n");
1250                         break;
1251                 }
1252
1253                 if ((d = d->next))
1254                         continue;
1255
1256                 if (! --retries) {
1257                         pr_cont(" timed out!\n");
1258                         break;
1259                 }
1260
1261                 d = ic_first_dev;
1262
1263                 timeout = timeout CONF_TIMEOUT_MULT;
1264                 if (timeout > CONF_TIMEOUT_MAX)
1265                         timeout = CONF_TIMEOUT_MAX;
1266
1267                 pr_cont(".");
1268         }
1269
1270 #ifdef IPCONFIG_BOOTP
1271         if (do_bootp)
1272                 ic_bootp_cleanup();
1273 #endif
1274 #ifdef IPCONFIG_RARP
1275         if (do_rarp)
1276                 ic_rarp_cleanup();
1277 #endif
1278
1279         if (!ic_got_reply) {
1280                 ic_myaddr = NONE;
1281                 return -1;
1282         }
1283
1284         pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1285                 ((ic_got_reply & IC_RARP) ? "RARP"
1286                 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1287                 &ic_addrservaddr, &ic_myaddr);
1288
1289         return 0;
1290 }
1291
1292 #endif /* IPCONFIG_DYNAMIC */
1293
1294 #ifdef CONFIG_PROC_FS
1295 /* proc_dir_entry for /proc/net/ipconfig */
1296 static struct proc_dir_entry *ipconfig_dir;
1297
1298 /* Name servers: */
1299 static int pnp_seq_show(struct seq_file *seq, void *v)
1300 {
1301         int i;
1302
1303         if (ic_proto_used & IC_PROTO)
1304                 seq_printf(seq, "#PROTO: %s\n",
1305                            (ic_proto_used & IC_RARP) ? "RARP"
1306                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1307         else
1308                 seq_puts(seq, "#MANUAL\n");
1309
1310         if (ic_domain[0])
1311                 seq_printf(seq,
1312                            "domain %s\n", ic_domain);
1313         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1314                 if (ic_nameservers[i] != NONE)
1315                         seq_printf(seq, "nameserver %pI4\n",
1316                                    &ic_nameservers[i]);
1317         }
1318         if (ic_servaddr != NONE)
1319                 seq_printf(seq, "bootserver %pI4\n",
1320                            &ic_servaddr);
1321         return 0;
1322 }
1323
1324 /* Create the /proc/net/ipconfig directory */
1325 static int __init ipconfig_proc_net_init(void)
1326 {
1327         ipconfig_dir = proc_net_mkdir(&init_net, "ipconfig", init_net.proc_net);
1328         if (!ipconfig_dir)
1329                 return -ENOMEM;
1330
1331         return 0;
1332 }
1333
1334 /* Create a new file under /proc/net/ipconfig */
1335 static int ipconfig_proc_net_create(const char *name,
1336                                     const struct file_operations *fops)
1337 {
1338         char *pname;
1339         struct proc_dir_entry *p;
1340
1341         if (!ipconfig_dir)
1342                 return -ENOMEM;
1343
1344         pname = kasprintf(GFP_KERNEL, "%s%s", "ipconfig/", name);
1345         if (!pname)
1346                 return -ENOMEM;
1347
1348         p = proc_create(pname, 0444, init_net.proc_net, fops);
1349         kfree(pname);
1350         if (!p)
1351                 return -ENOMEM;
1352
1353         return 0;
1354 }
1355
1356 /* Write NTP server IP addresses to /proc/net/ipconfig/ntp_servers */
1357 static int ntp_servers_seq_show(struct seq_file *seq, void *v)
1358 {
1359         int i;
1360
1361         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1362                 if (ic_ntp_servers[i] != NONE)
1363                         seq_printf(seq, "%pI4\n", &ic_ntp_servers[i]);
1364         }
1365         return 0;
1366 }
1367
1368 static int ntp_servers_seq_open(struct inode *inode, struct file *file)
1369 {
1370         return single_open(file, ntp_servers_seq_show, NULL);
1371 }
1372
1373 static const struct file_operations ntp_servers_seq_fops = {
1374         .open           = ntp_servers_seq_open,
1375         .read           = seq_read,
1376         .llseek         = seq_lseek,
1377         .release        = single_release,
1378 };
1379 #endif /* CONFIG_PROC_FS */
1380
1381 /*
1382  *  Extract IP address from the parameter string if needed. Note that we
1383  *  need to have root_server_addr set _before_ IPConfig gets called as it
1384  *  can override it.
1385  */
1386 __be32 __init root_nfs_parse_addr(char *name)
1387 {
1388         __be32 addr;
1389         int octets = 0;
1390         char *cp, *cq;
1391
1392         cp = cq = name;
1393         while (octets < 4) {
1394                 while (*cp >= '0' && *cp <= '9')
1395                         cp++;
1396                 if (cp == cq || cp - cq > 3)
1397                         break;
1398                 if (*cp == '.' || octets == 3)
1399                         octets++;
1400                 if (octets < 4)
1401                         cp++;
1402                 cq = cp;
1403         }
1404         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1405                 if (*cp == ':')
1406                         *cp++ = '\0';
1407                 addr = in_aton(name);
1408                 memmove(name, cp, strlen(cp) + 1);
1409         } else
1410                 addr = NONE;
1411
1412         return addr;
1413 }
1414
1415 #define DEVICE_WAIT_MAX         12 /* 12 seconds */
1416
1417 static int __init wait_for_devices(void)
1418 {
1419         int i;
1420
1421         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1422                 struct net_device *dev;
1423                 int found = 0;
1424
1425                 rtnl_lock();
1426                 for_each_netdev(&init_net, dev) {
1427                         if (ic_is_init_dev(dev)) {
1428                                 found = 1;
1429                                 break;
1430                         }
1431                 }
1432                 rtnl_unlock();
1433                 if (found)
1434                         return 0;
1435                 ssleep(1);
1436         }
1437         return -ENODEV;
1438 }
1439
1440 /*
1441  *      IP Autoconfig dispatcher.
1442  */
1443
1444 static int __init ip_auto_config(void)
1445 {
1446         __be32 addr;
1447 #ifdef IPCONFIG_DYNAMIC
1448         int retries = CONF_OPEN_RETRIES;
1449 #endif
1450         int err;
1451         unsigned int i;
1452
1453         /* Initialise all name servers and NTP servers to NONE (but only if the
1454          * "ip=" or "nfsaddrs=" kernel command line parameters weren't decoded,
1455          * otherwise we'll overwrite the IP addresses specified there)
1456          */
1457         if (ic_set_manually == 0) {
1458                 ic_nameservers_predef();
1459                 ic_ntp_servers_predef();
1460         }
1461
1462 #ifdef CONFIG_PROC_FS
1463         proc_create_single("pnp", 0444, init_net.proc_net, pnp_seq_show);
1464
1465         if (ipconfig_proc_net_init() == 0)
1466                 ipconfig_proc_net_create("ntp_servers", &ntp_servers_seq_fops);
1467 #endif /* CONFIG_PROC_FS */
1468
1469         if (!ic_enable)
1470                 return 0;
1471
1472         pr_debug("IP-Config: Entered.\n");
1473 #ifdef IPCONFIG_DYNAMIC
1474  try_try_again:
1475 #endif
1476         /* Wait for devices to appear */
1477         err = wait_for_devices();
1478         if (err)
1479                 return err;
1480
1481         /* Setup all network devices */
1482         err = ic_open_devs();
1483         if (err)
1484                 return err;
1485
1486         /* Give drivers a chance to settle */
1487         msleep(CONF_POST_OPEN);
1488
1489         /*
1490          * If the config information is insufficient (e.g., our IP address or
1491          * IP address of the boot server is missing or we have multiple network
1492          * interfaces and no default was set), use BOOTP or RARP to get the
1493          * missing values.
1494          */
1495         if (ic_myaddr == NONE ||
1496 #ifdef CONFIG_ROOT_NFS
1497             (root_server_addr == NONE &&
1498              ic_servaddr == NONE &&
1499              ROOT_DEV == Root_NFS) ||
1500 #endif
1501             ic_first_dev->next) {
1502 #ifdef IPCONFIG_DYNAMIC
1503                 if (ic_dynamic() < 0) {
1504                         ic_close_devs();
1505
1506                         /*
1507                          * I don't know why, but sometimes the
1508                          * eepro100 driver (at least) gets upset and
1509                          * doesn't work the first time it's opened.
1510                          * But then if you close it and reopen it, it
1511                          * works just fine.  So we need to try that at
1512                          * least once before giving up.
1513                          *
1514                          * Also, if the root will be NFS-mounted, we
1515                          * have nowhere to go if DHCP fails.  So we
1516                          * just have to keep trying forever.
1517                          *
1518                          *                              -- Chip
1519                          */
1520 #ifdef CONFIG_ROOT_NFS
1521                         if (ROOT_DEV ==  Root_NFS) {
1522                                 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1523                                 goto try_try_again;
1524                         }
1525 #endif
1526
1527                         if (--retries) {
1528                                 pr_err("IP-Config: Reopening network devices...\n");
1529                                 goto try_try_again;
1530                         }
1531
1532                         /* Oh, well.  At least we tried. */
1533                         pr_err("IP-Config: Auto-configuration of network failed\n");
1534                         return -1;
1535                 }
1536 #else /* !DYNAMIC */
1537                 pr_err("IP-Config: Incomplete network configuration information\n");
1538                 ic_close_devs();
1539                 return -1;
1540 #endif /* IPCONFIG_DYNAMIC */
1541         } else {
1542                 /* Device selected manually or only one device -> use it */
1543                 ic_dev = ic_first_dev;
1544         }
1545
1546         addr = root_nfs_parse_addr(root_server_path);
1547         if (root_server_addr == NONE)
1548                 root_server_addr = addr;
1549
1550         /*
1551          * Use defaults wherever applicable.
1552          */
1553         if (ic_defaults() < 0)
1554                 return -1;
1555
1556         /*
1557          * Record which protocol was actually used.
1558          */
1559 #ifdef IPCONFIG_DYNAMIC
1560         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1561 #endif
1562
1563 #ifndef IPCONFIG_SILENT
1564         /*
1565          * Clue in the operator.
1566          */
1567         pr_info("IP-Config: Complete:\n");
1568
1569         pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1570                 ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1571                 &ic_myaddr, &ic_netmask, &ic_gateway);
1572         pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1573                 utsname()->nodename, ic_domain, utsname()->domainname);
1574         pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1575                 &ic_servaddr, &root_server_addr, root_server_path);
1576         if (ic_dev_mtu)
1577                 pr_cont(", mtu=%d", ic_dev_mtu);
1578         /* Name servers (if any): */
1579         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1580                 if (ic_nameservers[i] != NONE) {
1581                         if (i == 0)
1582                                 pr_info("     nameserver%u=%pI4",
1583                                         i, &ic_nameservers[i]);
1584                         else
1585                                 pr_cont(", nameserver%u=%pI4",
1586                                         i, &ic_nameservers[i]);
1587                 }
1588                 if (i + 1 == CONF_NAMESERVERS_MAX)
1589                         pr_cont("\n");
1590         }
1591         /* NTP servers (if any): */
1592         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1593                 if (ic_ntp_servers[i] != NONE) {
1594                         if (i == 0)
1595                                 pr_info("     ntpserver%u=%pI4",
1596                                         i, &ic_ntp_servers[i]);
1597                         else
1598                                 pr_cont(", ntpserver%u=%pI4",
1599                                         i, &ic_ntp_servers[i]);
1600                 }
1601                 if (i + 1 == CONF_NTP_SERVERS_MAX)
1602                         pr_cont("\n");
1603         }
1604 #endif /* !SILENT */
1605
1606         /*
1607          * Close all network devices except the device we've
1608          * autoconfigured and set up routes.
1609          */
1610         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1611                 err = -1;
1612         else
1613                 err = 0;
1614
1615         ic_close_devs();
1616
1617         return err;
1618 }
1619
1620 late_initcall(ip_auto_config);
1621
1622
1623 /*
1624  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1625  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1626  */
1627 static int __init ic_proto_name(char *name)
1628 {
1629         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1630                 return 1;
1631         }
1632         if (!strcmp(name, "off") || !strcmp(name, "none")) {
1633                 return 0;
1634         }
1635 #ifdef CONFIG_IP_PNP_DHCP
1636         else if (!strncmp(name, "dhcp", 4)) {
1637                 char *client_id;
1638
1639                 ic_proto_enabled &= ~IC_RARP;
1640                 client_id = strstr(name, "dhcp,");
1641                 if (client_id) {
1642                         char *v;
1643
1644                         client_id = client_id + 5;
1645                         v = strchr(client_id, ',');
1646                         if (!v)
1647                                 return 1;
1648                         *v = 0;
1649                         if (kstrtou8(client_id, 0, dhcp_client_identifier))
1650                                 pr_debug("DHCP: Invalid client identifier type\n");
1651                         strncpy(dhcp_client_identifier + 1, v + 1, 251);
1652                         *v = ',';
1653                 }
1654                 return 1;
1655         }
1656 #endif
1657 #ifdef CONFIG_IP_PNP_BOOTP
1658         else if (!strcmp(name, "bootp")) {
1659                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1660                 return 1;
1661         }
1662 #endif
1663 #ifdef CONFIG_IP_PNP_RARP
1664         else if (!strcmp(name, "rarp")) {
1665                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1666                 return 1;
1667         }
1668 #endif
1669 #ifdef IPCONFIG_DYNAMIC
1670         else if (!strcmp(name, "both")) {
1671                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1672                 return 1;
1673         }
1674 #endif
1675         return 0;
1676 }
1677
1678 static int __init ip_auto_config_setup(char *addrs)
1679 {
1680         char *cp, *ip, *dp;
1681         int num = 0;
1682
1683         ic_set_manually = 1;
1684         ic_enable = 1;
1685
1686         /*
1687          * If any dhcp, bootp etc options are set, leave autoconfig on
1688          * and skip the below static IP processing.
1689          */
1690         if (ic_proto_name(addrs))
1691                 return 1;
1692
1693         /* If no static IP is given, turn off autoconfig and bail.  */
1694         if (*addrs == 0 ||
1695             strcmp(addrs, "off") == 0 ||
1696             strcmp(addrs, "none") == 0) {
1697                 ic_enable = 0;
1698                 return 1;
1699         }
1700
1701         /* Initialise all name servers and NTP servers to NONE */
1702         ic_nameservers_predef();
1703         ic_ntp_servers_predef();
1704
1705         /* Parse string for static IP assignment.  */
1706         ip = addrs;
1707         while (ip && *ip) {
1708                 if ((cp = strchr(ip, ':')))
1709                         *cp++ = '\0';
1710                 if (strlen(ip) > 0) {
1711                         pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1712                         switch (num) {
1713                         case 0:
1714                                 if ((ic_myaddr = in_aton(ip)) == ANY)
1715                                         ic_myaddr = NONE;
1716                                 break;
1717                         case 1:
1718                                 if ((ic_servaddr = in_aton(ip)) == ANY)
1719                                         ic_servaddr = NONE;
1720                                 break;
1721                         case 2:
1722                                 if ((ic_gateway = in_aton(ip)) == ANY)
1723                                         ic_gateway = NONE;
1724                                 break;
1725                         case 3:
1726                                 if ((ic_netmask = in_aton(ip)) == ANY)
1727                                         ic_netmask = NONE;
1728                                 break;
1729                         case 4:
1730                                 if ((dp = strchr(ip, '.'))) {
1731                                         *dp++ = '\0';
1732                                         strlcpy(utsname()->domainname, dp,
1733                                                 sizeof(utsname()->domainname));
1734                                 }
1735                                 strlcpy(utsname()->nodename, ip,
1736                                         sizeof(utsname()->nodename));
1737                                 ic_host_name_set = 1;
1738                                 break;
1739                         case 5:
1740                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1741                                 break;
1742                         case 6:
1743                                 if (ic_proto_name(ip) == 0 &&
1744                                     ic_myaddr == NONE) {
1745                                         ic_enable = 0;
1746                                 }
1747                                 break;
1748                         case 7:
1749                                 if (CONF_NAMESERVERS_MAX >= 1) {
1750                                         ic_nameservers[0] = in_aton(ip);
1751                                         if (ic_nameservers[0] == ANY)
1752                                                 ic_nameservers[0] = NONE;
1753                                 }
1754                                 break;
1755                         case 8:
1756                                 if (CONF_NAMESERVERS_MAX >= 2) {
1757                                         ic_nameservers[1] = in_aton(ip);
1758                                         if (ic_nameservers[1] == ANY)
1759                                                 ic_nameservers[1] = NONE;
1760                                 }
1761                                 break;
1762                         case 9:
1763                                 if (CONF_NTP_SERVERS_MAX >= 1) {
1764                                         ic_ntp_servers[0] = in_aton(ip);
1765                                         if (ic_ntp_servers[0] == ANY)
1766                                                 ic_ntp_servers[0] = NONE;
1767                                 }
1768                                 break;
1769                         }
1770                 }
1771                 ip = cp;
1772                 num++;
1773         }
1774
1775         return 1;
1776 }
1777 __setup("ip=", ip_auto_config_setup);
1778
1779 static int __init nfsaddrs_config_setup(char *addrs)
1780 {
1781         return ip_auto_config_setup(addrs);
1782 }
1783 __setup("nfsaddrs=", nfsaddrs_config_setup);
1784
1785 static int __init vendor_class_identifier_setup(char *addrs)
1786 {
1787         if (strlcpy(vendor_class_identifier, addrs,
1788                     sizeof(vendor_class_identifier))
1789             >= sizeof(vendor_class_identifier))
1790                 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1791                         vendor_class_identifier);
1792         return 1;
1793 }
1794 __setup("dhcpclass=", vendor_class_identifier_setup);