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 /* proc_dir_entry for /proc/net/ipconfig */
 167 static struct proc_dir_entry *ipconfig_dir;
 168
 169 /* Name of user-selected boot device */
 170 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 171
 172 /* Protocols supported by available interfaces */
 173 static int ic_proto_have_if __initdata;
 174
 175 /* MTU for boot device */
 176 static int ic_dev_mtu __initdata;
 177
 178 #ifdef IPCONFIG_DYNAMIC
 179 static DEFINE_SPINLOCK(ic_recv_lock);
 180 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
 181 #endif
 182 #ifdef IPCONFIG_DHCP
 183 static int ic_dhcp_msgtype __initdata;  /* DHCP msg type received */
 184 #endif
 185
 186
 187 /*
 188  *      Network devices
 189  */
 190
 191 struct ic_device {
 192         struct ic_device *next;
 193         struct net_device *dev;
 194         unsigned short flags;
 195         short able;
 196         __be32 xid;
 197 };
 198
 199 static struct ic_device *ic_first_dev __initdata;       /* List of open device */
 200 static struct ic_device *ic_dev __initdata;             /* Selected device */
 201
 202 static bool __init ic_is_init_dev(struct net_device *dev)
 203 {
 204         if (dev->flags & IFF_LOOPBACK)
 205                 return false;
 206         return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 207             (!(dev->flags & IFF_LOOPBACK) &&
 208              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 209              strncmp(dev->name, "dummy", 5));
 210 }
 211
 212 static int __init ic_open_devs(void)
 213 {
 214         struct ic_device *d, **last;
 215         struct net_device *dev;
 216         unsigned short oflags;
 217         unsigned long start, next_msg;
 218
 219         last = &ic_first_dev;
 220         rtnl_lock();
 221
 222         /* bring loopback and DSA master network devices up first */
 223         for_each_netdev(&init_net, dev) {
 224                 if (!(dev->flags & IFF_LOOPBACK) && !netdev_uses_dsa(dev))
 225                         continue;
 226                 if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
 227                         pr_err("IP-Config: Failed to open %s\n", dev->name);
 228         }
 229
 230         for_each_netdev(&init_net, dev) {
 231                 if (ic_is_init_dev(dev)) {
 232                         int able = 0;
 233                         if (dev->mtu >= 364)
 234                                 able |= IC_BOOTP;
 235                         else
 236                                 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
 237                                         dev->name, dev->mtu);
 238                         if (!(dev->flags & IFF_NOARP))
 239                                 able |= IC_RARP;
 240                         able &= ic_proto_enabled;
 241                         if (ic_proto_enabled && !able)
 242                                 continue;
 243                         oflags = dev->flags;
 244                         if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
 245                                 pr_err("IP-Config: Failed to open %s\n",
 246                                        dev->name);
 247                                 continue;
 248                         }
 249                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 250                                 rtnl_unlock();
 251                                 return -ENOMEM;
 252                         }
 253                         d->dev = dev;
 254                         *last = d;
 255                         last = &d->next;
 256                         d->flags = oflags;
 257                         d->able = able;
 258                         if (able & IC_BOOTP)
 259                                 get_random_bytes(&d->xid, sizeof(__be32));
 260                         else
 261                                 d->xid = 0;
 262                         ic_proto_have_if |= able;
 263                         pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
 264                                  dev->name, able, d->xid);
 265                 }
 266         }
 267
 268         /* no point in waiting if we could not bring up at least one device */
 269         if (!ic_first_dev)
 270                 goto have_carrier;
 271
 272         /* wait for a carrier on at least one device */
 273         start = jiffies;
 274         next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
 275         while (time_before(jiffies, start +
 276                            msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
 277                 int wait, elapsed;
 278
 279                 for_each_netdev(&init_net, dev)
 280                         if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
 281                                 goto have_carrier;
 282
 283                 msleep(1);
 284
 285                 if (time_before(jiffies, next_msg))
 286                         continue;
 287
 288                 elapsed = jiffies_to_msecs(jiffies - start);
 289                 wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
 290                 pr_info("Waiting up to %d more seconds for network.\n", wait);
 291                 next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
 292         }
 293 have_carrier:
 294         rtnl_unlock();
 295
 296         *last = NULL;
 297
 298         if (!ic_first_dev) {
 299                 if (user_dev_name[0])
 300                         pr_err("IP-Config: Device `%s' not found\n",
 301                                user_dev_name);
 302                 else
 303                         pr_err("IP-Config: No network devices available\n");
 304                 return -ENODEV;
 305         }
 306         return 0;
 307 }
 308
 309 static void __init ic_close_devs(void)
 310 {
 311         struct ic_device *d, *next;
 312         struct net_device *dev;
 313
 314         rtnl_lock();
 315         next = ic_first_dev;
 316         while ((d = next)) {
 317                 next = d->next;
 318                 dev = d->dev;
 319                 if (d != ic_dev && !netdev_uses_dsa(dev)) {
 320                         pr_debug("IP-Config: Downing %s\n", dev->name);
 321                         dev_change_flags(dev, d->flags);
 322                 }
 323                 kfree(d);
 324         }
 325         rtnl_unlock();
 326 }
 327
 328 /*
 329  *      Interface to various network functions.
 330  */
 331
 332 static inline void
 333 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
 334 {
 335         sin->sin_family = AF_INET;
 336         sin->sin_addr.s_addr = addr;
 337         sin->sin_port = port;
 338 }
 339
 340 /*
 341  *      Set up interface addresses and routes.
 342  */
 343
 344 static int __init ic_setup_if(void)
 345 {
 346         struct ifreq ir;
 347         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 348         int err;
 349
 350         memset(&ir, 0, sizeof(ir));
 351         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
 352         set_sockaddr(sin, ic_myaddr, 0);
 353         if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) {
 354                 pr_err("IP-Config: Unable to set interface address (%d)\n",
 355                        err);
 356                 return -1;
 357         }
 358         set_sockaddr(sin, ic_netmask, 0);
 359         if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) {
 360                 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
 361                        err);
 362                 return -1;
 363         }
 364         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 365         if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) {
 366                 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
 367                        err);
 368                 return -1;
 369         }
 370         /* Handle the case where we need non-standard MTU on the boot link (a network
 371          * using jumbo frames, for instance).  If we can't set the mtu, don't error
 372          * out, we'll try to muddle along.
 373          */
 374         if (ic_dev_mtu != 0) {
 375                 rtnl_lock();
 376                 if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0)
 377                         pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
 378                                ic_dev_mtu, err);
 379                 rtnl_unlock();
 380         }
 381         return 0;
 382 }
 383
 384 static int __init ic_setup_routes(void)
 385 {
 386         /* No need to setup device routes, only the default route... */
 387
 388         if (ic_gateway != NONE) {
 389                 struct rtentry rm;
 390                 int err;
 391
 392                 memset(&rm, 0, sizeof(rm));
 393                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 394                         pr_err("IP-Config: Gateway not on directly connected network\n");
 395                         return -1;
 396                 }
 397                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 398                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 399                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 400                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 401                 if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) {
 402                         pr_err("IP-Config: Cannot add default route (%d)\n",
 403                                err);
 404                         return -1;
 405                 }
 406         }
 407
 408         return 0;
 409 }
 410
 411 /*
 412  *      Fill in default values for all missing parameters.
 413  */
 414
 415 static int __init ic_defaults(void)
 416 {
 417         /*
 418          *      At this point we have no userspace running so need not
 419          *      claim locks on system_utsname
 420          */
 421
 422         if (!ic_host_name_set)
 423                 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
 424
 425         if (root_server_addr == NONE)
 426                 root_server_addr = ic_servaddr;
 427
 428         if (ic_netmask == NONE) {
 429                 if (IN_CLASSA(ntohl(ic_myaddr)))
 430                         ic_netmask = htonl(IN_CLASSA_NET);
 431                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 432                         ic_netmask = htonl(IN_CLASSB_NET);
 433                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 434                         ic_netmask = htonl(IN_CLASSC_NET);
 435                 else {
 436                         pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
 437                                &ic_myaddr);
 438                         return -1;
 439                 }
 440                 pr_notice("IP-Config: Guessing netmask %pI4\n",
 441                           &ic_netmask);
 442         }
 443
 444         return 0;
 445 }
 446
 447 /*
 448  *      RARP support.
 449  */
 450
 451 #ifdef IPCONFIG_RARP
 452
 453 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 454
 455 static struct packet_type rarp_packet_type __initdata = {
 456         .type = cpu_to_be16(ETH_P_RARP),
 457         .func = ic_rarp_recv,
 458 };
 459
 460 static inline void __init ic_rarp_init(void)
 461 {
 462         dev_add_pack(&rarp_packet_type);
 463 }
 464
 465 static inline void __init ic_rarp_cleanup(void)
 466 {
 467         dev_remove_pack(&rarp_packet_type);
 468 }
 469
 470 /*
 471  *  Process received RARP packet.
 472  */
 473 static int __init
 474 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 475 {
 476         struct arphdr *rarp;
 477         unsigned char *rarp_ptr;
 478         __be32 sip, tip;
 479         unsigned char *tha;             /* t for "target" */
 480         struct ic_device *d;
 481
 482         if (!net_eq(dev_net(dev), &init_net))
 483                 goto drop;
 484
 485         skb = skb_share_check(skb, GFP_ATOMIC);
 486         if (!skb)
 487                 return NET_RX_DROP;
 488
 489         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 490                 goto drop;
 491
 492         /* Basic sanity checks can be done without the lock.  */
 493         rarp = (struct arphdr *)skb_transport_header(skb);
 494
 495         /* If this test doesn't pass, it's not IP, or we should
 496          * ignore it anyway.
 497          */
 498         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 499                 goto drop;
 500
 501         /* If it's not a RARP reply, delete it. */
 502         if (rarp->ar_op != htons(ARPOP_RREPLY))
 503                 goto drop;
 504
 505         /* If it's not Ethernet, delete it. */
 506         if (rarp->ar_pro != htons(ETH_P_IP))
 507                 goto drop;
 508
 509         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
 510                 goto drop;
 511
 512         /* OK, it is all there and looks valid, process... */
 513         rarp = (struct arphdr *)skb_transport_header(skb);
 514         rarp_ptr = (unsigned char *) (rarp + 1);
 515
 516         /* One reply at a time, please. */
 517         spin_lock(&ic_recv_lock);
 518
 519         /* If we already have a reply, just drop the packet */
 520         if (ic_got_reply)
 521                 goto drop_unlock;
 522
 523         /* Find the ic_device that the packet arrived on */
 524         d = ic_first_dev;
 525         while (d && d->dev != dev)
 526                 d = d->next;
 527         if (!d)
 528                 goto drop_unlock;       /* should never happen */
 529
 530         /* Extract variable-width fields */
 531         rarp_ptr += dev->addr_len;
 532         memcpy(&sip, rarp_ptr, 4);
 533         rarp_ptr += 4;
 534         tha = rarp_ptr;
 535         rarp_ptr += dev->addr_len;
 536         memcpy(&tip, rarp_ptr, 4);
 537
 538         /* Discard packets which are not meant for us. */
 539         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 540                 goto drop_unlock;
 541
 542         /* Discard packets which are not from specified server. */
 543         if (ic_servaddr != NONE && ic_servaddr != sip)
 544                 goto drop_unlock;
 545
 546         /* We have a winner! */
 547         ic_dev = d;
 548         if (ic_myaddr == NONE)
 549                 ic_myaddr = tip;
 550         ic_servaddr = sip;
 551         ic_addrservaddr = sip;
 552         ic_got_reply = IC_RARP;
 553
 554 drop_unlock:
 555         /* Show's over.  Nothing to see here.  */
 556         spin_unlock(&ic_recv_lock);
 557
 558 drop:
 559         /* Throw the packet out. */
 560         kfree_skb(skb);
 561         return 0;
 562 }
 563
 564
 565 /*
 566  *  Send RARP request packet over a single interface.
 567  */
 568 static void __init ic_rarp_send_if(struct ic_device *d)
 569 {
 570         struct net_device *dev = d->dev;
 571         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 572                  dev->dev_addr, dev->dev_addr);
 573 }
 574 #endif
 575
 576 /*
 577  *  Predefine Nameservers
 578  */
 579 static inline void __init ic_nameservers_predef(void)
 580 {
 581         int i;
 582
 583         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 584                 ic_nameservers[i] = NONE;
 585 }
 586
 587 /* Predefine NTP servers */
 588 static inline void __init ic_ntp_servers_predef(void)
 589 {
 590         int i;
 591
 592         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++)
 593                 ic_ntp_servers[i] = NONE;
 594 }
 595
 596 /*
 597  *      DHCP/BOOTP support.
 598  */
 599
 600 #ifdef IPCONFIG_BOOTP
 601
 602 struct bootp_pkt {              /* BOOTP packet format */
 603         struct iphdr iph;       /* IP header */
 604         struct udphdr udph;     /* UDP header */
 605         u8 op;                  /* 1=request, 2=reply */
 606         u8 htype;               /* HW address type */
 607         u8 hlen;                /* HW address length */
 608         u8 hops;                /* Used only by gateways */
 609         __be32 xid;             /* Transaction ID */
 610         __be16 secs;            /* Seconds since we started */
 611         __be16 flags;           /* Just what it says */
 612         __be32 client_ip;               /* Client's IP address if known */
 613         __be32 your_ip;         /* Assigned IP address */
 614         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
 615         __be32 relay_ip;                /* IP address of BOOTP relay */
 616         u8 hw_addr[16];         /* Client's HW address */
 617         u8 serv_name[64];       /* Server host name */
 618         u8 boot_file[128];      /* Name of boot file */
 619         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 620 };
 621
 622 /* packet ops */
 623 #define BOOTP_REQUEST   1
 624 #define BOOTP_REPLY     2
 625
 626 /* DHCP message types */
 627 #define DHCPDISCOVER    1
 628 #define DHCPOFFER       2
 629 #define DHCPREQUEST     3
 630 #define DHCPDECLINE     4
 631 #define DHCPACK         5
 632 #define DHCPNAK         6
 633 #define DHCPRELEASE     7
 634 #define DHCPINFORM      8
 635
 636 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 637
 638 static struct packet_type bootp_packet_type __initdata = {
 639         .type = cpu_to_be16(ETH_P_IP),
 640         .func = ic_bootp_recv,
 641 };
 642
 643 /*
 644  *  Initialize DHCP/BOOTP extension fields in the request.
 645  */
 646
 647 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 648
 649 #ifdef IPCONFIG_DHCP
 650
 651 static void __init
 652 ic_dhcp_init_options(u8 *options, struct ic_device *d)
 653 {
 654         u8 mt = ((ic_servaddr == NONE)
 655                  ? DHCPDISCOVER : DHCPREQUEST);
 656         u8 *e = options;
 657         int len;
 658
 659         pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
 660
 661         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 662         e += 4;
 663
 664         *e++ = 53;              /* DHCP message type */
 665         *e++ = 1;
 666         *e++ = mt;
 667
 668         if (mt == DHCPREQUEST) {
 669                 *e++ = 54;      /* Server ID (IP address) */
 670                 *e++ = 4;
 671                 memcpy(e, &ic_servaddr, 4);
 672                 e += 4;
 673
 674                 *e++ = 50;      /* Requested IP address */
 675                 *e++ = 4;
 676                 memcpy(e, &ic_myaddr, 4);
 677                 e += 4;
 678         }
 679
 680         /* always? */
 681         {
 682                 static const u8 ic_req_params[] = {
 683                         1,      /* Subnet mask */
 684                         3,      /* Default gateway */
 685                         6,      /* DNS server */
 686                         12,     /* Host name */
 687                         15,     /* Domain name */
 688                         17,     /* Boot path */
 689                         26,     /* MTU */
 690                         40,     /* NIS domain name */
 691                         42,     /* NTP servers */
 692                 };
 693
 694                 *e++ = 55;      /* Parameter request list */
 695                 *e++ = sizeof(ic_req_params);
 696                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 697                 e += sizeof(ic_req_params);
 698
 699                 if (ic_host_name_set) {
 700                         *e++ = 12;      /* host-name */
 701                         len = strlen(utsname()->nodename);
 702                         *e++ = len;
 703                         memcpy(e, utsname()->nodename, len);
 704                         e += len;
 705                 }
 706                 if (*vendor_class_identifier) {
 707                         pr_info("DHCP: sending class identifier \"%s\"\n",
 708                                 vendor_class_identifier);
 709                         *e++ = 60;      /* Class-identifier */
 710                         len = strlen(vendor_class_identifier);
 711                         *e++ = len;
 712                         memcpy(e, vendor_class_identifier, len);
 713                         e += len;
 714                 }
 715                 len = strlen(dhcp_client_identifier + 1);
 716                 /* the minimum length of identifier is 2, include 1 byte type,
 717                  * and can not be larger than the length of options
 718                  */
 719                 if (len >= 1 && len < 312 - (e - options) - 1) {
 720                         *e++ = 61;
 721                         *e++ = len + 1;
 722                         memcpy(e, dhcp_client_identifier, len + 1);
 723                         e += len + 1;
 724                 }
 725         }
 726
 727         *e++ = 255;     /* End of the list */
 728 }
 729
 730 #endif /* IPCONFIG_DHCP */
 731
 732 static void __init ic_bootp_init_ext(u8 *e)
 733 {
 734         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 735         e += 4;
 736         *e++ = 1;               /* Subnet mask request */
 737         *e++ = 4;
 738         e += 4;
 739         *e++ = 3;               /* Default gateway request */
 740         *e++ = 4;
 741         e += 4;
 742 #if CONF_NAMESERVERS_MAX > 0
 743         *e++ = 6;               /* (DNS) name server request */
 744         *e++ = 4 * CONF_NAMESERVERS_MAX;
 745         e += 4 * CONF_NAMESERVERS_MAX;
 746 #endif
 747         *e++ = 12;              /* Host name request */
 748         *e++ = 32;
 749         e += 32;
 750         *e++ = 40;              /* NIS Domain name request */
 751         *e++ = 32;
 752         e += 32;
 753         *e++ = 17;              /* Boot path */
 754         *e++ = 40;
 755         e += 40;
 756
 757         *e++ = 57;              /* set extension buffer size for reply */
 758         *e++ = 2;
 759         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 760         *e++ = 150;
 761
 762         *e++ = 255;             /* End of the list */
 763 }
 764
 765
 766 /*
 767  *  Initialize the DHCP/BOOTP mechanism.
 768  */
 769 static inline void __init ic_bootp_init(void)
 770 {
 771         /* Re-initialise all name servers and NTP servers to NONE, in case any
 772          * were set via the "ip=" or "nfsaddrs=" kernel command line parameters:
 773          * any IP addresses specified there will already have been decoded but
 774          * are no longer needed
 775          */
 776         ic_nameservers_predef();
 777         ic_ntp_servers_predef();
 778
 779         dev_add_pack(&bootp_packet_type);
 780 }
 781
 782
 783 /*
 784  *  DHCP/BOOTP cleanup.
 785  */
 786 static inline void __init ic_bootp_cleanup(void)
 787 {
 788         dev_remove_pack(&bootp_packet_type);
 789 }
 790
 791
 792 /*
 793  *  Send DHCP/BOOTP request to single interface.
 794  */
 795 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 796 {
 797         struct net_device *dev = d->dev;
 798         struct sk_buff *skb;
 799         struct bootp_pkt *b;
 800         struct iphdr *h;
 801         int hlen = LL_RESERVED_SPACE(dev);
 802         int tlen = dev->needed_tailroom;
 803
 804         /* Allocate packet */
 805         skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
 806                         GFP_KERNEL);
 807         if (!skb)
 808                 return;
 809         skb_reserve(skb, hlen);
 810         b = skb_put_zero(skb, sizeof(struct bootp_pkt));
 811
 812         /* Construct IP header */
 813         skb_reset_network_header(skb);
 814         h = ip_hdr(skb);
 815         h->version = 4;
 816         h->ihl = 5;
 817         h->tot_len = htons(sizeof(struct bootp_pkt));
 818         h->frag_off = htons(IP_DF);
 819         h->ttl = 64;
 820         h->protocol = IPPROTO_UDP;
 821         h->daddr = htonl(INADDR_BROADCAST);
 822         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 823
 824         /* Construct UDP header */
 825         b->udph.source = htons(68);
 826         b->udph.dest = htons(67);
 827         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 828         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 829
 830         /* Construct DHCP/BOOTP header */
 831         b->op = BOOTP_REQUEST;
 832         if (dev->type < 256) /* check for false types */
 833                 b->htype = dev->type;
 834         else if (dev->type == ARPHRD_FDDI)
 835                 b->htype = ARPHRD_ETHER;
 836         else {
 837                 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
 838                         dev->name);
 839                 b->htype = dev->type; /* can cause undefined behavior */
 840         }
 841
 842         /* server_ip and your_ip address are both already zero per RFC2131 */
 843         b->hlen = dev->addr_len;
 844         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 845         b->secs = htons(jiffies_diff / HZ);
 846         b->xid = d->xid;
 847
 848         /* add DHCP options or BOOTP extensions */
 849 #ifdef IPCONFIG_DHCP
 850         if (ic_proto_enabled & IC_USE_DHCP)
 851                 ic_dhcp_init_options(b->exten, d);
 852         else
 853 #endif
 854                 ic_bootp_init_ext(b->exten);
 855
 856         /* Chain packet down the line... */
 857         skb->dev = dev;
 858         skb->protocol = htons(ETH_P_IP);
 859         if (dev_hard_header(skb, dev, ntohs(skb->protocol),
 860                             dev->broadcast, dev->dev_addr, skb->len) < 0) {
 861                 kfree_skb(skb);
 862                 printk("E");
 863                 return;
 864         }
 865
 866         if (dev_queue_xmit(skb) < 0)
 867                 printk("E");
 868 }
 869
 870
 871 /*
 872  *  Copy BOOTP-supplied string if not already set.
 873  */
 874 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 875 {
 876         if (!len)
 877                 return 0;
 878         if (len > max-1)
 879                 len = max-1;
 880         memcpy(dest, src, len);
 881         dest[len] = '\0';
 882         return 1;
 883 }
 884
 885
 886 /*
 887  *  Process BOOTP extensions.
 888  */
 889 static void __init ic_do_bootp_ext(u8 *ext)
 890 {
 891         u8 servers;
 892         int i;
 893         __be16 mtu;
 894
 895         u8 *c;
 896
 897         pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
 898         for (c=ext+2; c<ext+2+ext[1]; c++)
 899                 pr_debug(" %02x", *c);
 900         pr_debug("\n");
 901
 902         switch (*ext++) {
 903         case 1:         /* Subnet mask */
 904                 if (ic_netmask == NONE)
 905                         memcpy(&ic_netmask, ext+1, 4);
 906                 break;
 907         case 3:         /* Default gateway */
 908                 if (ic_gateway == NONE)
 909                         memcpy(&ic_gateway, ext+1, 4);
 910                 break;
 911         case 6:         /* DNS server */
 912                 servers= *ext/4;
 913                 if (servers > CONF_NAMESERVERS_MAX)
 914                         servers = CONF_NAMESERVERS_MAX;
 915                 for (i = 0; i < servers; i++) {
 916                         if (ic_nameservers[i] == NONE)
 917                                 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 918                 }
 919                 break;
 920         case 12:        /* Host name */
 921                 ic_bootp_string(utsname()->nodename, ext+1, *ext,
 922                                 __NEW_UTS_LEN);
 923                 ic_host_name_set = 1;
 924                 break;
 925         case 15:        /* Domain name (DNS) */
 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
1296 /* Name servers: */
1297 static int pnp_seq_show(struct seq_file *seq, void *v)
1298 {
1299         int i;
1300
1301         if (ic_proto_used & IC_PROTO)
1302                 seq_printf(seq, "#PROTO: %s\n",
1303                            (ic_proto_used & IC_RARP) ? "RARP"
1304                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1305         else
1306                 seq_puts(seq, "#MANUAL\n");
1307
1308         if (ic_domain[0])
1309                 seq_printf(seq,
1310                            "domain %s\n", ic_domain);
1311         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1312                 if (ic_nameservers[i] != NONE)
1313                         seq_printf(seq, "nameserver %pI4\n",
1314                                    &ic_nameservers[i]);
1315         }
1316         if (ic_servaddr != NONE)
1317                 seq_printf(seq, "bootserver %pI4\n",
1318                            &ic_servaddr);
1319         return 0;
1320 }
1321
1322 static int pnp_seq_open(struct inode *indoe, struct file *file)
1323 {
1324         return single_open(file, pnp_seq_show, NULL);
1325 }
1326
1327 static const struct file_operations pnp_seq_fops = {
1328         .open           = pnp_seq_open,
1329         .read           = seq_read,
1330         .llseek         = seq_lseek,
1331         .release        = single_release,
1332 };
1333
1334 /* Create the /proc/net/ipconfig directory */
1335 static int __init ipconfig_proc_net_init(void)
1336 {
1337         ipconfig_dir = proc_net_mkdir(&init_net, "ipconfig", init_net.proc_net);
1338         if (!ipconfig_dir)
1339                 return -ENOMEM;
1340
1341         return 0;
1342 }
1343
1344 /* Create a new file under /proc/net/ipconfig */
1345 static int ipconfig_proc_net_create(const char *name,
1346                                     const struct file_operations *fops)
1347 {
1348         char *pname;
1349         struct proc_dir_entry *p;
1350
1351         if (!ipconfig_dir)
1352                 return -ENOMEM;
1353
1354         pname = kasprintf(GFP_KERNEL, "%s%s", "ipconfig/", name);
1355         if (!pname)
1356                 return -ENOMEM;
1357
1358         p = proc_create(pname, 0444, init_net.proc_net, fops);
1359         kfree(pname);
1360         if (!p)
1361                 return -ENOMEM;
1362
1363         return 0;
1364 }
1365
1366 /* Write NTP server IP addresses to /proc/net/ipconfig/ntp_servers */
1367 static int ntp_servers_seq_show(struct seq_file *seq, void *v)
1368 {
1369         int i;
1370
1371         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1372                 if (ic_ntp_servers[i] != NONE)
1373                         seq_printf(seq, "%pI4\n", &ic_ntp_servers[i]);
1374         }
1375         return 0;
1376 }
1377
1378 static int ntp_servers_seq_open(struct inode *inode, struct file *file)
1379 {
1380         return single_open(file, ntp_servers_seq_show, NULL);
1381 }
1382
1383 static const struct file_operations ntp_servers_seq_fops = {
1384         .open           = ntp_servers_seq_open,
1385         .read           = seq_read,
1386         .llseek         = seq_lseek,
1387         .release        = single_release,
1388 };
1389 #endif /* CONFIG_PROC_FS */
1390
1391 /*
1392  *  Extract IP address from the parameter string if needed. Note that we
1393  *  need to have root_server_addr set _before_ IPConfig gets called as it
1394  *  can override it.
1395  */
1396 __be32 __init root_nfs_parse_addr(char *name)
1397 {
1398         __be32 addr;
1399         int octets = 0;
1400         char *cp, *cq;
1401
1402         cp = cq = name;
1403         while (octets < 4) {
1404                 while (*cp >= '0' && *cp <= '9')
1405                         cp++;
1406                 if (cp == cq || cp - cq > 3)
1407                         break;
1408                 if (*cp == '.' || octets == 3)
1409                         octets++;
1410                 if (octets < 4)
1411                         cp++;
1412                 cq = cp;
1413         }
1414         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1415                 if (*cp == ':')
1416                         *cp++ = '\0';
1417                 addr = in_aton(name);
1418                 memmove(name, cp, strlen(cp) + 1);
1419         } else
1420                 addr = NONE;
1421
1422         return addr;
1423 }
1424
1425 #define DEVICE_WAIT_MAX         12 /* 12 seconds */
1426
1427 static int __init wait_for_devices(void)
1428 {
1429         int i;
1430
1431         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1432                 struct net_device *dev;
1433                 int found = 0;
1434
1435                 rtnl_lock();
1436                 for_each_netdev(&init_net, dev) {
1437                         if (ic_is_init_dev(dev)) {
1438                                 found = 1;
1439                                 break;
1440                         }
1441                 }
1442                 rtnl_unlock();
1443                 if (found)
1444                         return 0;
1445                 ssleep(1);
1446         }
1447         return -ENODEV;
1448 }
1449
1450 /*
1451  *      IP Autoconfig dispatcher.
1452  */
1453
1454 static int __init ip_auto_config(void)
1455 {
1456         __be32 addr;
1457 #ifdef IPCONFIG_DYNAMIC
1458         int retries = CONF_OPEN_RETRIES;
1459 #endif
1460         int err;
1461         unsigned int i;
1462
1463         /* Initialise all name servers and NTP servers to NONE (but only if the
1464          * "ip=" or "nfsaddrs=" kernel command line parameters weren't decoded,
1465          * otherwise we'll overwrite the IP addresses specified there)
1466          */
1467         if (ic_set_manually == 0) {
1468                 ic_nameservers_predef();
1469                 ic_ntp_servers_predef();
1470         }
1471
1472 #ifdef CONFIG_PROC_FS
1473         proc_create("pnp", 0444, init_net.proc_net, &pnp_seq_fops);
1474
1475         if (ipconfig_proc_net_init() == 0)
1476                 ipconfig_proc_net_create("ntp_servers", &ntp_servers_seq_fops);
1477 #endif /* CONFIG_PROC_FS */
1478
1479         if (!ic_enable)
1480                 return 0;
1481
1482         pr_debug("IP-Config: Entered.\n");
1483 #ifdef IPCONFIG_DYNAMIC
1484  try_try_again:
1485 #endif
1486         /* Wait for devices to appear */
1487         err = wait_for_devices();
1488         if (err)
1489                 return err;
1490
1491         /* Setup all network devices */
1492         err = ic_open_devs();
1493         if (err)
1494                 return err;
1495
1496         /* Give drivers a chance to settle */
1497         msleep(CONF_POST_OPEN);
1498
1499         /*
1500          * If the config information is insufficient (e.g., our IP address or
1501          * IP address of the boot server is missing or we have multiple network
1502          * interfaces and no default was set), use BOOTP or RARP to get the
1503          * missing values.
1504          */
1505         if (ic_myaddr == NONE ||
1506 #ifdef CONFIG_ROOT_NFS
1507             (root_server_addr == NONE &&
1508              ic_servaddr == NONE &&
1509              ROOT_DEV == Root_NFS) ||
1510 #endif
1511             ic_first_dev->next) {
1512 #ifdef IPCONFIG_DYNAMIC
1513                 if (ic_dynamic() < 0) {
1514                         ic_close_devs();
1515
1516                         /*
1517                          * I don't know why, but sometimes the
1518                          * eepro100 driver (at least) gets upset and
1519                          * doesn't work the first time it's opened.
1520                          * But then if you close it and reopen it, it
1521                          * works just fine.  So we need to try that at
1522                          * least once before giving up.
1523                          *
1524                          * Also, if the root will be NFS-mounted, we
1525                          * have nowhere to go if DHCP fails.  So we
1526                          * just have to keep trying forever.
1527                          *
1528                          *                              -- Chip
1529                          */
1530 #ifdef CONFIG_ROOT_NFS
1531                         if (ROOT_DEV ==  Root_NFS) {
1532                                 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1533                                 goto try_try_again;
1534                         }
1535 #endif
1536
1537                         if (--retries) {
1538                                 pr_err("IP-Config: Reopening network devices...\n");
1539                                 goto try_try_again;
1540                         }
1541
1542                         /* Oh, well.  At least we tried. */
1543                         pr_err("IP-Config: Auto-configuration of network failed\n");
1544                         return -1;
1545                 }
1546 #else /* !DYNAMIC */
1547                 pr_err("IP-Config: Incomplete network configuration information\n");
1548                 ic_close_devs();
1549                 return -1;
1550 #endif /* IPCONFIG_DYNAMIC */
1551         } else {
1552                 /* Device selected manually or only one device -> use it */
1553                 ic_dev = ic_first_dev;
1554         }
1555
1556         addr = root_nfs_parse_addr(root_server_path);
1557         if (root_server_addr == NONE)
1558                 root_server_addr = addr;
1559
1560         /*
1561          * Use defaults wherever applicable.
1562          */
1563         if (ic_defaults() < 0)
1564                 return -1;
1565
1566         /*
1567          * Record which protocol was actually used.
1568          */
1569 #ifdef IPCONFIG_DYNAMIC
1570         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1571 #endif
1572
1573 #ifndef IPCONFIG_SILENT
1574         /*
1575          * Clue in the operator.
1576          */
1577         pr_info("IP-Config: Complete:\n");
1578
1579         pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1580                 ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1581                 &ic_myaddr, &ic_netmask, &ic_gateway);
1582         pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1583                 utsname()->nodename, ic_domain, utsname()->domainname);
1584         pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1585                 &ic_servaddr, &root_server_addr, root_server_path);
1586         if (ic_dev_mtu)
1587                 pr_cont(", mtu=%d", ic_dev_mtu);
1588         /* Name servers (if any): */
1589         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1590                 if (ic_nameservers[i] != NONE) {
1591                         if (i == 0)
1592                                 pr_info("     nameserver%u=%pI4",
1593                                         i, &ic_nameservers[i]);
1594                         else
1595                                 pr_cont(", nameserver%u=%pI4",
1596                                         i, &ic_nameservers[i]);
1597                 }
1598                 if (i + 1 == CONF_NAMESERVERS_MAX)
1599                         pr_cont("\n");
1600         }
1601         /* NTP servers (if any): */
1602         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1603                 if (ic_ntp_servers[i] != NONE) {
1604                         if (i == 0)
1605                                 pr_info("     ntpserver%u=%pI4",
1606                                         i, &ic_ntp_servers[i]);
1607                         else
1608                                 pr_cont(", ntpserver%u=%pI4",
1609                                         i, &ic_ntp_servers[i]);
1610                 }
1611                 if (i + 1 == CONF_NTP_SERVERS_MAX)
1612                         pr_cont("\n");
1613         }
1614 #endif /* !SILENT */
1615
1616         /*
1617          * Close all network devices except the device we've
1618          * autoconfigured and set up routes.
1619          */
1620         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1621                 err = -1;
1622         else
1623                 err = 0;
1624
1625         ic_close_devs();
1626
1627         return err;
1628 }
1629
1630 late_initcall(ip_auto_config);
1631
1632
1633 /*
1634  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1635  *  command line parameter.  See Documentation/filesystems/nfs/nfsroot.txt.
1636  */
1637 static int __init ic_proto_name(char *name)
1638 {
1639         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1640                 return 1;
1641         }
1642         if (!strcmp(name, "off") || !strcmp(name, "none")) {
1643                 return 0;
1644         }
1645 #ifdef CONFIG_IP_PNP_DHCP
1646         else if (!strncmp(name, "dhcp", 4)) {
1647                 char *client_id;
1648
1649                 ic_proto_enabled &= ~IC_RARP;
1650                 client_id = strstr(name, "dhcp,");
1651                 if (client_id) {
1652                         char *v;
1653
1654                         client_id = client_id + 5;
1655                         v = strchr(client_id, ',');
1656                         if (!v)
1657                                 return 1;
1658                         *v = 0;
1659                         if (kstrtou8(client_id, 0, dhcp_client_identifier))
1660                                 pr_debug("DHCP: Invalid client identifier type\n");
1661                         strncpy(dhcp_client_identifier + 1, v + 1, 251);
1662                         *v = ',';
1663                 }
1664                 return 1;
1665         }
1666 #endif
1667 #ifdef CONFIG_IP_PNP_BOOTP
1668         else if (!strcmp(name, "bootp")) {
1669                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1670                 return 1;
1671         }
1672 #endif
1673 #ifdef CONFIG_IP_PNP_RARP
1674         else if (!strcmp(name, "rarp")) {
1675                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1676                 return 1;
1677         }
1678 #endif
1679 #ifdef IPCONFIG_DYNAMIC
1680         else if (!strcmp(name, "both")) {
1681                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1682                 return 1;
1683         }
1684 #endif
1685         return 0;
1686 }
1687
1688 static int __init ip_auto_config_setup(char *addrs)
1689 {
1690         char *cp, *ip, *dp;
1691         int num = 0;
1692
1693         ic_set_manually = 1;
1694         ic_enable = 1;
1695
1696         /*
1697          * If any dhcp, bootp etc options are set, leave autoconfig on
1698          * and skip the below static IP processing.
1699          */
1700         if (ic_proto_name(addrs))
1701                 return 1;
1702
1703         /* If no static IP is given, turn off autoconfig and bail.  */
1704         if (*addrs == 0 ||
1705             strcmp(addrs, "off") == 0 ||
1706             strcmp(addrs, "none") == 0) {
1707                 ic_enable = 0;
1708                 return 1;
1709         }
1710
1711         /* Initialise all name servers and NTP servers to NONE */
1712         ic_nameservers_predef();
1713         ic_ntp_servers_predef();
1714
1715         /* Parse string for static IP assignment.  */
1716         ip = addrs;
1717         while (ip && *ip) {
1718                 if ((cp = strchr(ip, ':')))
1719                         *cp++ = '\0';
1720                 if (strlen(ip) > 0) {
1721                         pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1722                         switch (num) {
1723                         case 0:
1724                                 if ((ic_myaddr = in_aton(ip)) == ANY)
1725                                         ic_myaddr = NONE;
1726                                 break;
1727                         case 1:
1728                                 if ((ic_servaddr = in_aton(ip)) == ANY)
1729                                         ic_servaddr = NONE;
1730                                 break;
1731                         case 2:
1732                                 if ((ic_gateway = in_aton(ip)) == ANY)
1733                                         ic_gateway = NONE;
1734                                 break;
1735                         case 3:
1736                                 if ((ic_netmask = in_aton(ip)) == ANY)
1737                                         ic_netmask = NONE;
1738                                 break;
1739                         case 4:
1740                                 if ((dp = strchr(ip, '.'))) {
1741                                         *dp++ = '\0';
1742                                         strlcpy(utsname()->domainname, dp,
1743                                                 sizeof(utsname()->domainname));
1744                                 }
1745                                 strlcpy(utsname()->nodename, ip,
1746                                         sizeof(utsname()->nodename));
1747                                 ic_host_name_set = 1;
1748                                 break;
1749                         case 5:
1750                                 strlcpy(user_dev_name, ip, sizeof(user_dev_name));
1751                                 break;
1752                         case 6:
1753                                 if (ic_proto_name(ip) == 0 &&
1754                                     ic_myaddr == NONE) {
1755                                         ic_enable = 0;
1756                                 }
1757                                 break;
1758                         case 7:
1759                                 if (CONF_NAMESERVERS_MAX >= 1) {
1760                                         ic_nameservers[0] = in_aton(ip);
1761                                         if (ic_nameservers[0] == ANY)
1762                                                 ic_nameservers[0] = NONE;
1763                                 }
1764                                 break;
1765                         case 8:
1766                                 if (CONF_NAMESERVERS_MAX >= 2) {
1767                                         ic_nameservers[1] = in_aton(ip);
1768                                         if (ic_nameservers[1] == ANY)
1769                                                 ic_nameservers[1] = NONE;
1770                                 }
1771                                 break;
1772                         case 9:
1773                                 if (CONF_NTP_SERVERS_MAX >= 1) {
1774                                         ic_ntp_servers[0] = in_aton(ip);
1775                                         if (ic_ntp_servers[0] == ANY)
1776                                                 ic_ntp_servers[0] = NONE;
1777                                 }
1778                                 break;
1779                         }
1780                 }
1781                 ip = cp;
1782                 num++;
1783         }
1784
1785         return 1;
1786 }
1787 __setup("ip=", ip_auto_config_setup);
1788
1789 static int __init nfsaddrs_config_setup(char *addrs)
1790 {
1791         return ip_auto_config_setup(addrs);
1792 }
1793 __setup("nfsaddrs=", nfsaddrs_config_setup);
1794
1795 static int __init vendor_class_identifier_setup(char *addrs)
1796 {
1797         if (strlcpy(vendor_class_identifier, addrs,
1798                     sizeof(vendor_class_identifier))
1799             >= sizeof(vendor_class_identifier))
1800                 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1801                         vendor_class_identifier);
1802         return 1;
1803 }
1804 __setup("dhcpclass=", vendor_class_identifier_setup);