net/ipv4/ipconfig.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
   4  *  user-supplied information to configure own IP address and routes.
   5  *
   6  *  Copyright (C) 1996-1998 Martin Mares <[email protected]>
   7  *
   8  *  Derived from network configuration code in fs/nfs/nfsroot.c,
   9  *  originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
  10  *
  11  *  BOOTP rewritten to construct and analyse packets itself instead
  12  *  of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
  13  *                                           -- MJ, December 1998
  14  *
  15  *  Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
  16  *  initialization scheme.
  17  *      - Arnaldo Carvalho de Melo <[email protected]>, 08/11/1999
  18  *
  19  *  DHCP support added.  To users this looks like a whole separate
  20  *  protocol, but we know it's just a bag on the side of BOOTP.
  21  *              -- Chip Salzenberg <[email protected]>, May 2000
  22  *
  23  *  Ported DHCP support from 2.2.16 to 2.4.0-test4
  24  *              -- Eric Biederman <[email protected]>, 30 Aug 2000
  25  *
  26  *  Merged changes from 2.2.19 into 2.4.3
  27  *              -- Eric Biederman <[email protected]>, 22 April Aug 2001
  28  *
  29  *  Multiple Nameservers in /proc/net/pnp
  30  *              --  Josef Siemes <[email protected]>, Aug 2002
  31  *
  32  *  NTP servers in /proc/net/ipconfig/ntp_servers
  33  *              --  Chris Novakovic <[email protected]>, 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/ip.h>
  65 #include <net/ipconfig.h>
  66 #include <net/route.h>
  67
  68 #include <linux/uaccess.h>
  69 #include <net/checksum.h>
  70 #include <asm/processor.h>
  71
  72 #if defined(CONFIG_IP_PNP_DHCP)
  73 #define IPCONFIG_DHCP
  74 #endif
  75 #if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
  76 #define IPCONFIG_BOOTP
  77 #endif
  78 #if defined(CONFIG_IP_PNP_RARP)
  79 #define IPCONFIG_RARP
  80 #endif
  81 #if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
  82 #define IPCONFIG_DYNAMIC
  83 #endif
  84
  85 /* Define the friendly delay before and after opening net devices */
  86 #define CONF_POST_OPEN          10      /* After opening: 10 msecs */
  87
  88 /* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
  89 #define CONF_OPEN_RETRIES       2       /* (Re)open devices twice */
  90 #define CONF_SEND_RETRIES       6       /* Send six requests per open */
  91 #define CONF_BASE_TIMEOUT       (HZ*2)  /* Initial timeout: 2 seconds */
  92 #define CONF_TIMEOUT_RANDOM     (HZ)    /* Maximum amount of randomization */
  93 #define CONF_TIMEOUT_MULT       *7/4    /* Rate of timeout growth */
  94 #define CONF_TIMEOUT_MAX        (HZ*30) /* Maximum allowed timeout */
  95 #define CONF_NAMESERVERS_MAX   3       /* Maximum number of nameservers
  96                                            - '3' from resolv.h */
  97 #define CONF_NTP_SERVERS_MAX   3        /* Maximum number of NTP servers */
  98
  99 #define NONE cpu_to_be32(INADDR_NONE)
 100 #define ANY cpu_to_be32(INADDR_ANY)
 101
 102 /* Wait for carrier timeout default in seconds */
 103 static unsigned int carrier_timeout = 120;
 104
 105 /*
 106  * Public IP configuration
 107  */
 108
 109 /* This is used by platforms which might be able to set the ipconfig
 110  * variables using firmware environment vars.  If this is set, it will
 111  * ignore such firmware variables.
 112  */
 113 int ic_set_manually __initdata = 0;             /* IPconfig parameters set manually */
 114
 115 static int ic_enable __initdata;                /* IP config enabled? */
 116
 117 /* Protocol choice */
 118 int ic_proto_enabled __initdata = 0
 119 #ifdef IPCONFIG_BOOTP
 120                         | IC_BOOTP
 121 #endif
 122 #ifdef CONFIG_IP_PNP_DHCP
 123                         | IC_USE_DHCP
 124 #endif
 125 #ifdef IPCONFIG_RARP
 126                         | IC_RARP
 127 #endif
 128                         ;
 129
 130 static int ic_host_name_set __initdata; /* Host name set by us? */
 131
 132 __be32 ic_myaddr = NONE;                /* My IP address */
 133 static __be32 ic_netmask = NONE;        /* Netmask for local subnet */
 134 __be32 ic_gateway = NONE;       /* Gateway IP address */
 135
 136 #ifdef IPCONFIG_DYNAMIC
 137 static __be32 ic_addrservaddr = NONE;   /* IP Address of the IP addresses'server */
 138 #endif
 139
 140 __be32 ic_servaddr = NONE;      /* Boot server IP address */
 141
 142 __be32 root_server_addr = NONE; /* Address of NFS server */
 143 u8 root_server_path[256] = { 0, };      /* Path to mount as root */
 144
 145 /* vendor class identifier */
 146 static char vendor_class_identifier[253] __initdata;
 147
 148 #if defined(CONFIG_IP_PNP_DHCP)
 149 static char dhcp_client_identifier[253] __initdata;
 150 #endif
 151
 152 /* Persistent data: */
 153
 154 #ifdef IPCONFIG_DYNAMIC
 155 static int ic_proto_used;                       /* Protocol used, if any */
 156 #else
 157 #define ic_proto_used 0
 158 #endif
 159 static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
 160 static __be32 ic_ntp_servers[CONF_NTP_SERVERS_MAX]; /* NTP server IP addresses */
 161 static u8 ic_domain[64];                /* DNS (not NIS) domain name */
 162
 163 /*
 164  * Private state.
 165  */
 166
 167 /* Name of user-selected boot device */
 168 static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
 169
 170 /* Protocols supported by available interfaces */
 171 static int ic_proto_have_if __initdata;
 172
 173 /* MTU for boot device */
 174 static int ic_dev_mtu __initdata;
 175
 176 #ifdef IPCONFIG_DYNAMIC
 177 static DEFINE_SPINLOCK(ic_recv_lock);
 178 static volatile int ic_got_reply __initdata;    /* Proto(s) that replied */
 179 #endif
 180 #ifdef IPCONFIG_DHCP
 181 static int ic_dhcp_msgtype __initdata;  /* DHCP msg type received */
 182 #endif
 183
 184
 185 /*
 186  *      Network devices
 187  */
 188
 189 struct ic_device {
 190         struct ic_device *next;
 191         struct net_device *dev;
 192         unsigned short flags;
 193         short able;
 194         __be32 xid;
 195 };
 196
 197 static struct ic_device *ic_first_dev __initdata;       /* List of open device */
 198 static struct ic_device *ic_dev __initdata;             /* Selected device */
 199
 200 static bool __init ic_is_init_dev(struct net_device *dev)
 201 {
 202         if (dev->flags & IFF_LOOPBACK)
 203                 return false;
 204         return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
 205             (!(dev->flags & IFF_LOOPBACK) &&
 206              (dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
 207              strncmp(dev->name, "dummy", 5));
 208 }
 209
 210 static int __init ic_open_devs(void)
 211 {
 212         struct ic_device *d, **last;
 213         struct net_device *dev;
 214         unsigned short oflags;
 215         unsigned long start, next_msg;
 216
 217         last = &ic_first_dev;
 218         rtnl_lock();
 219
 220         /* bring loopback device up first */
 221         for_each_netdev(&init_net, dev) {
 222                 if (!(dev->flags & IFF_LOOPBACK))
 223                         continue;
 224                 if (dev_change_flags(dev, dev->flags | IFF_UP, NULL) < 0)
 225                         pr_err("IP-Config: Failed to open %s\n", dev->name);
 226         }
 227
 228         for_each_netdev(&init_net, dev) {
 229                 if (ic_is_init_dev(dev)) {
 230                         int able = 0;
 231                         if (dev->mtu >= 364)
 232                                 able |= IC_BOOTP;
 233                         else
 234                                 pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small\n",
 235                                         dev->name, dev->mtu);
 236                         if (!(dev->flags & IFF_NOARP))
 237                                 able |= IC_RARP;
 238                         able &= ic_proto_enabled;
 239                         if (ic_proto_enabled && !able)
 240                                 continue;
 241                         oflags = dev->flags;
 242                         if (dev_change_flags(dev, oflags | IFF_UP, NULL) < 0) {
 243                                 pr_err("IP-Config: Failed to open %s\n",
 244                                        dev->name);
 245                                 continue;
 246                         }
 247                         if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
 248                                 rtnl_unlock();
 249                                 return -ENOMEM;
 250                         }
 251                         d->dev = dev;
 252                         *last = d;
 253                         last = &d->next;
 254                         d->flags = oflags;
 255                         d->able = able;
 256                         if (able & IC_BOOTP)
 257                                 get_random_bytes(&d->xid, sizeof(__be32));
 258                         else
 259                                 d->xid = 0;
 260                         ic_proto_have_if |= able;
 261                         pr_debug("IP-Config: %s UP (able=%d, xid=%08x)\n",
 262                                  dev->name, able, d->xid);
 263                 }
 264         }
 265         /* Devices with a complex topology like SFP ethernet interfaces needs
 266          * the rtnl_lock at init. The carrier wait-loop must therefore run
 267          * without holding it.
 268          */
 269         rtnl_unlock();
 270
 271         /* no point in waiting if we could not bring up at least one device */
 272         if (!ic_first_dev)
 273                 goto have_carrier;
 274
 275         /* wait for a carrier on at least one device */
 276         start = jiffies;
 277         next_msg = start + msecs_to_jiffies(20000);
 278         while (time_before(jiffies, start +
 279                            msecs_to_jiffies(carrier_timeout * 1000))) {
 280                 int wait, elapsed;
 281
 282                 rtnl_lock();
 283                 for_each_netdev(&init_net, dev)
 284                         if (ic_is_init_dev(dev) && netif_carrier_ok(dev)) {
 285                                 rtnl_unlock();
 286                                 goto have_carrier;
 287                         }
 288                 rtnl_unlock();
 289
 290                 msleep(1);
 291
 292                 if (time_before(jiffies, next_msg))
 293                         continue;
 294
 295                 elapsed = jiffies_to_msecs(jiffies - start);
 296                 wait = (carrier_timeout * 1000 - elapsed + 500) / 1000;
 297                 pr_info("Waiting up to %d more seconds for network.\n", wait);
 298                 next_msg = jiffies + msecs_to_jiffies(20000);
 299         }
 300 have_carrier:
 301
 302         *last = NULL;
 303
 304         if (!ic_first_dev) {
 305                 if (user_dev_name[0])
 306                         pr_err("IP-Config: Device `%s' not found\n",
 307                                user_dev_name);
 308                 else
 309                         pr_err("IP-Config: No network devices available\n");
 310                 return -ENODEV;
 311         }
 312         return 0;
 313 }
 314
 315 /* Close all network interfaces except the one we've autoconfigured, and its
 316  * lowers, in case it's a stacked virtual interface.
 317  */
 318 static void __init ic_close_devs(void)
 319 {
 320         struct net_device *selected_dev = ic_dev ? ic_dev->dev : NULL;
 321         struct ic_device *d, *next;
 322         struct net_device *dev;
 323
 324         rtnl_lock();
 325         next = ic_first_dev;
 326         while ((d = next)) {
 327                 bool bring_down = (d != ic_dev);
 328                 struct net_device *lower;
 329                 struct list_head *iter;
 330
 331                 next = d->next;
 332                 dev = d->dev;
 333
 334                 if (selected_dev) {
 335                         netdev_for_each_lower_dev(selected_dev, lower, iter) {
 336                                 if (dev == lower) {
 337                                         bring_down = false;
 338                                         break;
 339                                 }
 340                         }
 341                 }
 342                 if (bring_down) {
 343                         pr_debug("IP-Config: Downing %s\n", dev->name);
 344                         dev_change_flags(dev, d->flags, NULL);
 345                 }
 346                 kfree(d);
 347         }
 348         rtnl_unlock();
 349 }
 350
 351 /*
 352  *      Interface to various network functions.
 353  */
 354
 355 static inline void
 356 set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
 357 {
 358         sin->sin_family = AF_INET;
 359         sin->sin_addr.s_addr = addr;
 360         sin->sin_port = port;
 361 }
 362
 363 /*
 364  *      Set up interface addresses and routes.
 365  */
 366
 367 static int __init ic_setup_if(void)
 368 {
 369         struct ifreq ir;
 370         struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
 371         int err;
 372
 373         memset(&ir, 0, sizeof(ir));
 374         strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->dev->name);
 375         set_sockaddr(sin, ic_myaddr, 0);
 376         if ((err = devinet_ioctl(&init_net, SIOCSIFADDR, &ir)) < 0) {
 377                 pr_err("IP-Config: Unable to set interface address (%d)\n",
 378                        err);
 379                 return -1;
 380         }
 381         set_sockaddr(sin, ic_netmask, 0);
 382         if ((err = devinet_ioctl(&init_net, SIOCSIFNETMASK, &ir)) < 0) {
 383                 pr_err("IP-Config: Unable to set interface netmask (%d)\n",
 384                        err);
 385                 return -1;
 386         }
 387         set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
 388         if ((err = devinet_ioctl(&init_net, SIOCSIFBRDADDR, &ir)) < 0) {
 389                 pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
 390                        err);
 391                 return -1;
 392         }
 393         /* Handle the case where we need non-standard MTU on the boot link (a network
 394          * using jumbo frames, for instance).  If we can't set the mtu, don't error
 395          * out, we'll try to muddle along.
 396          */
 397         if (ic_dev_mtu != 0) {
 398                 rtnl_lock();
 399                 if ((err = dev_set_mtu(ic_dev->dev, ic_dev_mtu)) < 0)
 400                         pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
 401                                ic_dev_mtu, err);
 402                 rtnl_unlock();
 403         }
 404         return 0;
 405 }
 406
 407 static int __init ic_setup_routes(void)
 408 {
 409         /* No need to setup device routes, only the default route... */
 410
 411         if (ic_gateway != NONE) {
 412                 struct rtentry rm;
 413                 int err;
 414
 415                 memset(&rm, 0, sizeof(rm));
 416                 if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
 417                         pr_err("IP-Config: Gateway not on directly connected network\n");
 418                         return -1;
 419                 }
 420                 set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
 421                 set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
 422                 set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
 423                 rm.rt_flags = RTF_UP | RTF_GATEWAY;
 424                 if ((err = ip_rt_ioctl(&init_net, SIOCADDRT, &rm)) < 0) {
 425                         pr_err("IP-Config: Cannot add default route (%d)\n",
 426                                err);
 427                         return -1;
 428                 }
 429         }
 430
 431         return 0;
 432 }
 433
 434 /*
 435  *      Fill in default values for all missing parameters.
 436  */
 437
 438 static int __init ic_defaults(void)
 439 {
 440         /*
 441          *      At this point we have no userspace running so need not
 442          *      claim locks on system_utsname
 443          */
 444
 445         if (!ic_host_name_set)
 446                 sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
 447
 448         if (root_server_addr == NONE)
 449                 root_server_addr = ic_servaddr;
 450
 451         if (ic_netmask == NONE) {
 452                 if (IN_CLASSA(ntohl(ic_myaddr)))
 453                         ic_netmask = htonl(IN_CLASSA_NET);
 454                 else if (IN_CLASSB(ntohl(ic_myaddr)))
 455                         ic_netmask = htonl(IN_CLASSB_NET);
 456                 else if (IN_CLASSC(ntohl(ic_myaddr)))
 457                         ic_netmask = htonl(IN_CLASSC_NET);
 458                 else if (IN_CLASSE(ntohl(ic_myaddr)))
 459                         ic_netmask = htonl(IN_CLASSE_NET);
 460                 else {
 461                         pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
 462                                &ic_myaddr);
 463                         return -1;
 464                 }
 465                 pr_notice("IP-Config: Guessing netmask %pI4\n",
 466                           &ic_netmask);
 467         }
 468
 469         return 0;
 470 }
 471
 472 /*
 473  *      RARP support.
 474  */
 475
 476 #ifdef IPCONFIG_RARP
 477
 478 static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 479
 480 static struct packet_type rarp_packet_type __initdata = {
 481         .type = cpu_to_be16(ETH_P_RARP),
 482         .func = ic_rarp_recv,
 483 };
 484
 485 static inline void __init ic_rarp_init(void)
 486 {
 487         dev_add_pack(&rarp_packet_type);
 488 }
 489
 490 static inline void __init ic_rarp_cleanup(void)
 491 {
 492         dev_remove_pack(&rarp_packet_type);
 493 }
 494
 495 /*
 496  *  Process received RARP packet.
 497  */
 498 static int __init
 499 ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 500 {
 501         struct arphdr *rarp;
 502         unsigned char *rarp_ptr;
 503         __be32 sip, tip;
 504         unsigned char *tha;             /* t for "target" */
 505         struct ic_device *d;
 506
 507         if (!net_eq(dev_net(dev), &init_net))
 508                 goto drop;
 509
 510         skb = skb_share_check(skb, GFP_ATOMIC);
 511         if (!skb)
 512                 return NET_RX_DROP;
 513
 514         if (!pskb_may_pull(skb, sizeof(struct arphdr)))
 515                 goto drop;
 516
 517         /* Basic sanity checks can be done without the lock.  */
 518         rarp = (struct arphdr *)skb_transport_header(skb);
 519
 520         /* If this test doesn't pass, it's not IP, or we should
 521          * ignore it anyway.
 522          */
 523         if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
 524                 goto drop;
 525
 526         /* If it's not a RARP reply, delete it. */
 527         if (rarp->ar_op != htons(ARPOP_RREPLY))
 528                 goto drop;
 529
 530         /* If it's not Ethernet, delete it. */
 531         if (rarp->ar_pro != htons(ETH_P_IP))
 532                 goto drop;
 533
 534         if (!pskb_may_pull(skb, arp_hdr_len(dev)))
 535                 goto drop;
 536
 537         /* OK, it is all there and looks valid, process... */
 538         rarp = (struct arphdr *)skb_transport_header(skb);
 539         rarp_ptr = (unsigned char *) (rarp + 1);
 540
 541         /* One reply at a time, please. */
 542         spin_lock(&ic_recv_lock);
 543
 544         /* If we already have a reply, just drop the packet */
 545         if (ic_got_reply)
 546                 goto drop_unlock;
 547
 548         /* Find the ic_device that the packet arrived on */
 549         d = ic_first_dev;
 550         while (d && d->dev != dev)
 551                 d = d->next;
 552         if (!d)
 553                 goto drop_unlock;       /* should never happen */
 554
 555         /* Extract variable-width fields */
 556         rarp_ptr += dev->addr_len;
 557         memcpy(&sip, rarp_ptr, 4);
 558         rarp_ptr += 4;
 559         tha = rarp_ptr;
 560         rarp_ptr += dev->addr_len;
 561         memcpy(&tip, rarp_ptr, 4);
 562
 563         /* Discard packets which are not meant for us. */
 564         if (memcmp(tha, dev->dev_addr, dev->addr_len))
 565                 goto drop_unlock;
 566
 567         /* Discard packets which are not from specified server. */
 568         if (ic_servaddr != NONE && ic_servaddr != sip)
 569                 goto drop_unlock;
 570
 571         /* We have a winner! */
 572         ic_dev = d;
 573         if (ic_myaddr == NONE)
 574                 ic_myaddr = tip;
 575         ic_servaddr = sip;
 576         ic_addrservaddr = sip;
 577         ic_got_reply = IC_RARP;
 578
 579 drop_unlock:
 580         /* Show's over.  Nothing to see here.  */
 581         spin_unlock(&ic_recv_lock);
 582
 583 drop:
 584         /* Throw the packet out. */
 585         kfree_skb(skb);
 586         return 0;
 587 }
 588
 589
 590 /*
 591  *  Send RARP request packet over a single interface.
 592  */
 593 static void __init ic_rarp_send_if(struct ic_device *d)
 594 {
 595         struct net_device *dev = d->dev;
 596         arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
 597                  dev->dev_addr, dev->dev_addr);
 598 }
 599 #endif
 600
 601 /*
 602  *  Predefine Nameservers
 603  */
 604 static inline void __init ic_nameservers_predef(void)
 605 {
 606         int i;
 607
 608         for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
 609                 ic_nameservers[i] = NONE;
 610 }
 611
 612 /* Predefine NTP servers */
 613 static inline void __init ic_ntp_servers_predef(void)
 614 {
 615         int i;
 616
 617         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++)
 618                 ic_ntp_servers[i] = NONE;
 619 }
 620
 621 /*
 622  *      DHCP/BOOTP support.
 623  */
 624
 625 #ifdef IPCONFIG_BOOTP
 626
 627 struct bootp_pkt {              /* BOOTP packet format */
 628         struct iphdr iph;       /* IP header */
 629         struct udphdr udph;     /* UDP header */
 630         u8 op;                  /* 1=request, 2=reply */
 631         u8 htype;               /* HW address type */
 632         u8 hlen;                /* HW address length */
 633         u8 hops;                /* Used only by gateways */
 634         __be32 xid;             /* Transaction ID */
 635         __be16 secs;            /* Seconds since we started */
 636         __be16 flags;           /* Just what it says */
 637         __be32 client_ip;               /* Client's IP address if known */
 638         __be32 your_ip;         /* Assigned IP address */
 639         __be32 server_ip;               /* (Next, e.g. NFS) Server's IP address */
 640         __be32 relay_ip;                /* IP address of BOOTP relay */
 641         u8 hw_addr[16];         /* Client's HW address */
 642         u8 serv_name[64];       /* Server host name */
 643         u8 boot_file[128];      /* Name of boot file */
 644         u8 exten[312];          /* DHCP options / BOOTP vendor extensions */
 645 };
 646
 647 /* packet ops */
 648 #define BOOTP_REQUEST   1
 649 #define BOOTP_REPLY     2
 650
 651 /* DHCP message types */
 652 #define DHCPDISCOVER    1
 653 #define DHCPOFFER       2
 654 #define DHCPREQUEST     3
 655 #define DHCPDECLINE     4
 656 #define DHCPACK         5
 657 #define DHCPNAK         6
 658 #define DHCPRELEASE     7
 659 #define DHCPINFORM      8
 660
 661 static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
 662
 663 static struct packet_type bootp_packet_type __initdata = {
 664         .type = cpu_to_be16(ETH_P_IP),
 665         .func = ic_bootp_recv,
 666 };
 667
 668 /* DHCPACK can overwrite DNS if fallback was set upon first BOOTP reply */
 669 static int ic_nameservers_fallback __initdata;
 670
 671 /*
 672  *  Initialize DHCP/BOOTP extension fields in the request.
 673  */
 674
 675 static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
 676
 677 #ifdef IPCONFIG_DHCP
 678
 679 static void __init
 680 ic_dhcp_init_options(u8 *options, struct ic_device *d)
 681 {
 682         u8 mt = ((ic_servaddr == NONE)
 683                  ? DHCPDISCOVER : DHCPREQUEST);
 684         u8 *e = options;
 685         int len;
 686
 687         pr_debug("DHCP: Sending message type %d (%s)\n", mt, d->dev->name);
 688
 689         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 690         e += 4;
 691
 692         *e++ = 53;              /* DHCP message type */
 693         *e++ = 1;
 694         *e++ = mt;
 695
 696         if (mt == DHCPREQUEST) {
 697                 *e++ = 54;      /* Server ID (IP address) */
 698                 *e++ = 4;
 699                 memcpy(e, &ic_servaddr, 4);
 700                 e += 4;
 701
 702                 *e++ = 50;      /* Requested IP address */
 703                 *e++ = 4;
 704                 memcpy(e, &ic_myaddr, 4);
 705                 e += 4;
 706         }
 707
 708         /* always? */
 709         {
 710                 static const u8 ic_req_params[] = {
 711                         1,      /* Subnet mask */
 712                         3,      /* Default gateway */
 713                         6,      /* DNS server */
 714                         12,     /* Host name */
 715                         15,     /* Domain name */
 716                         17,     /* Boot path */
 717                         26,     /* MTU */
 718                         40,     /* NIS domain name */
 719                         42,     /* NTP servers */
 720                 };
 721
 722                 *e++ = 55;      /* Parameter request list */
 723                 *e++ = sizeof(ic_req_params);
 724                 memcpy(e, ic_req_params, sizeof(ic_req_params));
 725                 e += sizeof(ic_req_params);
 726
 727                 if (ic_host_name_set) {
 728                         *e++ = 12;      /* host-name */
 729                         len = strlen(utsname()->nodename);
 730                         *e++ = len;
 731                         memcpy(e, utsname()->nodename, len);
 732                         e += len;
 733                 }
 734                 if (*vendor_class_identifier) {
 735                         pr_info("DHCP: sending class identifier \"%s\"\n",
 736                                 vendor_class_identifier);
 737                         *e++ = 60;      /* Class-identifier */
 738                         len = strlen(vendor_class_identifier);
 739                         *e++ = len;
 740                         memcpy(e, vendor_class_identifier, len);
 741                         e += len;
 742                 }
 743                 len = strlen(dhcp_client_identifier + 1);
 744                 /* the minimum length of identifier is 2, include 1 byte type,
 745                  * and can not be larger than the length of options
 746                  */
 747                 if (len >= 1 && len < 312 - (e - options) - 1) {
 748                         *e++ = 61;
 749                         *e++ = len + 1;
 750                         memcpy(e, dhcp_client_identifier, len + 1);
 751                         e += len + 1;
 752                 }
 753         }
 754
 755         *e++ = 255;     /* End of the list */
 756 }
 757
 758 #endif /* IPCONFIG_DHCP */
 759
 760 static void __init ic_bootp_init_ext(u8 *e)
 761 {
 762         memcpy(e, ic_bootp_cookie, 4);  /* RFC1048 Magic Cookie */
 763         e += 4;
 764         *e++ = 1;               /* Subnet mask request */
 765         *e++ = 4;
 766         e += 4;
 767         *e++ = 3;               /* Default gateway request */
 768         *e++ = 4;
 769         e += 4;
 770 #if CONF_NAMESERVERS_MAX > 0
 771         *e++ = 6;               /* (DNS) name server request */
 772         *e++ = 4 * CONF_NAMESERVERS_MAX;
 773         e += 4 * CONF_NAMESERVERS_MAX;
 774 #endif
 775         *e++ = 12;              /* Host name request */
 776         *e++ = 32;
 777         e += 32;
 778         *e++ = 40;              /* NIS Domain name request */
 779         *e++ = 32;
 780         e += 32;
 781         *e++ = 17;              /* Boot path */
 782         *e++ = 40;
 783         e += 40;
 784
 785         *e++ = 57;              /* set extension buffer size for reply */
 786         *e++ = 2;
 787         *e++ = 1;               /* 128+236+8+20+14, see dhcpd sources */
 788         *e++ = 150;
 789
 790         *e++ = 255;             /* End of the list */
 791 }
 792
 793
 794 /*
 795  *  Initialize the DHCP/BOOTP mechanism.
 796  */
 797 static inline void __init ic_bootp_init(void)
 798 {
 799         /* Re-initialise all name servers and NTP servers to NONE, in case any
 800          * were set via the "ip=" or "nfsaddrs=" kernel command line parameters:
 801          * any IP addresses specified there will already have been decoded but
 802          * are no longer needed
 803          */
 804         ic_nameservers_predef();
 805         ic_ntp_servers_predef();
 806
 807         dev_add_pack(&bootp_packet_type);
 808 }
 809
 810
 811 /*
 812  *  DHCP/BOOTP cleanup.
 813  */
 814 static inline void __init ic_bootp_cleanup(void)
 815 {
 816         dev_remove_pack(&bootp_packet_type);
 817 }
 818
 819
 820 /*
 821  *  Send DHCP/BOOTP request to single interface.
 822  */
 823 static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
 824 {
 825         struct net_device *dev = d->dev;
 826         struct sk_buff *skb;
 827         struct bootp_pkt *b;
 828         struct iphdr *h;
 829         int hlen = LL_RESERVED_SPACE(dev);
 830         int tlen = dev->needed_tailroom;
 831
 832         /* Allocate packet */
 833         skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
 834                         GFP_KERNEL);
 835         if (!skb)
 836                 return;
 837         skb_reserve(skb, hlen);
 838         b = skb_put_zero(skb, sizeof(struct bootp_pkt));
 839
 840         /* Construct IP header */
 841         skb_reset_network_header(skb);
 842         h = ip_hdr(skb);
 843         h->version = 4;
 844         h->ihl = 5;
 845         h->tot_len = htons(sizeof(struct bootp_pkt));
 846         h->frag_off = htons(IP_DF);
 847         h->ttl = 64;
 848         h->protocol = IPPROTO_UDP;
 849         h->daddr = htonl(INADDR_BROADCAST);
 850         h->check = ip_fast_csum((unsigned char *) h, h->ihl);
 851
 852         /* Construct UDP header */
 853         b->udph.source = htons(68);
 854         b->udph.dest = htons(67);
 855         b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
 856         /* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
 857
 858         /* Construct DHCP/BOOTP header */
 859         b->op = BOOTP_REQUEST;
 860         if (dev->type < 256) /* check for false types */
 861                 b->htype = dev->type;
 862         else if (dev->type == ARPHRD_FDDI)
 863                 b->htype = ARPHRD_ETHER;
 864         else {
 865                 pr_warn("Unknown ARP type 0x%04x for device %s\n", dev->type,
 866                         dev->name);
 867                 b->htype = dev->type; /* can cause undefined behavior */
 868         }
 869
 870         /* server_ip and your_ip address are both already zero per RFC2131 */
 871         b->hlen = dev->addr_len;
 872         memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
 873         b->secs = htons(jiffies_diff / HZ);
 874         b->xid = d->xid;
 875
 876         /* add DHCP options or BOOTP extensions */
 877 #ifdef IPCONFIG_DHCP
 878         if (ic_proto_enabled & IC_USE_DHCP)
 879                 ic_dhcp_init_options(b->exten, d);
 880         else
 881 #endif
 882                 ic_bootp_init_ext(b->exten);
 883
 884         /* Chain packet down the line... */
 885         skb->dev = dev;
 886         skb->protocol = htons(ETH_P_IP);
 887         if (dev_hard_header(skb, dev, ntohs(skb->protocol),
 888                             dev->broadcast, dev->dev_addr, skb->len) < 0) {
 889                 kfree_skb(skb);
 890                 printk("E");
 891                 return;
 892         }
 893
 894         if (dev_queue_xmit(skb) < 0)
 895                 printk("E");
 896 }
 897
 898
 899 /*
 900  *  Copy BOOTP-supplied string
 901  */
 902 static int __init ic_bootp_string(char *dest, char *src, int len, int max)
 903 {
 904         if (!len)
 905                 return 0;
 906         if (len > max-1)
 907                 len = max-1;
 908         memcpy(dest, src, len);
 909         dest[len] = '\0';
 910         return 1;
 911 }
 912
 913
 914 /*
 915  *  Process BOOTP extensions.
 916  */
 917 static void __init ic_do_bootp_ext(u8 *ext)
 918 {
 919         u8 servers;
 920         int i;
 921         __be16 mtu;
 922
 923         u8 *c;
 924
 925         pr_debug("DHCP/BOOTP: Got extension %d:", *ext);
 926         for (c=ext+2; c<ext+2+ext[1]; c++)
 927                 pr_debug(" %02x", *c);
 928         pr_debug("\n");
 929
 930         switch (*ext++) {
 931         case 1:         /* Subnet mask */
 932                 if (ic_netmask == NONE)
 933                         memcpy(&ic_netmask, ext+1, 4);
 934                 break;
 935         case 3:         /* Default gateway */
 936                 if (ic_gateway == NONE)
 937                         memcpy(&ic_gateway, ext+1, 4);
 938                 break;
 939         case 6:         /* DNS server */
 940                 servers= *ext/4;
 941                 if (servers > CONF_NAMESERVERS_MAX)
 942                         servers = CONF_NAMESERVERS_MAX;
 943                 for (i = 0; i < servers; i++) {
 944                         if (ic_nameservers[i] == NONE ||
 945                             ic_nameservers_fallback)
 946                                 memcpy(&ic_nameservers[i], ext+1+4*i, 4);
 947                 }
 948                 break;
 949         case 12:        /* Host name */
 950                 if (!ic_host_name_set) {
 951                         ic_bootp_string(utsname()->nodename, ext+1, *ext,
 952                                         __NEW_UTS_LEN);
 953                         ic_host_name_set = 1;
 954                 }
 955                 break;
 956         case 15:        /* Domain name (DNS) */
 957                 if (!ic_domain[0])
 958                         ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
 959                 break;
 960         case 17:        /* Root path */
 961                 if (!root_server_path[0])
 962                         ic_bootp_string(root_server_path, ext+1, *ext,
 963                                         sizeof(root_server_path));
 964                 break;
 965         case 26:        /* Interface MTU */
 966                 memcpy(&mtu, ext+1, sizeof(mtu));
 967                 ic_dev_mtu = ntohs(mtu);
 968                 break;
 969         case 40:        /* NIS Domain name (_not_ DNS) */
 970                 ic_bootp_string(utsname()->domainname, ext+1, *ext,
 971                                 __NEW_UTS_LEN);
 972                 break;
 973         case 42:        /* NTP servers */
 974                 servers = *ext / 4;
 975                 if (servers > CONF_NTP_SERVERS_MAX)
 976                         servers = CONF_NTP_SERVERS_MAX;
 977                 for (i = 0; i < servers; i++) {
 978                         if (ic_ntp_servers[i] == NONE)
 979                                 memcpy(&ic_ntp_servers[i], ext+1+4*i, 4);
 980                 }
 981                 break;
 982         }
 983 }
 984
 985
 986 /*
 987  *  Receive BOOTP reply.
 988  */
 989 static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 990 {
 991         struct bootp_pkt *b;
 992         struct iphdr *h;
 993         struct ic_device *d;
 994         int len, ext_len;
 995
 996         if (!net_eq(dev_net(dev), &init_net))
 997                 goto drop;
 998
 999         /* Perform verifications before taking the lock.  */
1000         if (skb->pkt_type == PACKET_OTHERHOST)
1001                 goto drop;
1002
1003         skb = skb_share_check(skb, GFP_ATOMIC);
1004         if (!skb)
1005                 return NET_RX_DROP;
1006
1007         if (!pskb_may_pull(skb,
1008                            sizeof(struct iphdr) +
1009                            sizeof(struct udphdr)))
1010                 goto drop;
1011
1012         b = (struct bootp_pkt *)skb_network_header(skb);
1013         h = &b->iph;
1014
1015         if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
1016                 goto drop;
1017
1018         /* Fragments are not supported */
1019         if (ip_is_fragment(h)) {
1020                 net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
1021                 goto drop;
1022         }
1023
1024         if (skb->len < ntohs(h->tot_len))
1025                 goto drop;
1026
1027         if (ip_fast_csum((char *) h, h->ihl))
1028                 goto drop;
1029
1030         if (b->udph.source != htons(67) || b->udph.dest != htons(68))
1031                 goto drop;
1032
1033         if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
1034                 goto drop;
1035
1036         len = ntohs(b->udph.len) - sizeof(struct udphdr);
1037         ext_len = len - (sizeof(*b) -
1038                          sizeof(struct iphdr) -
1039                          sizeof(struct udphdr) -
1040                          sizeof(b->exten));
1041         if (ext_len < 0)
1042                 goto drop;
1043
1044         /* Ok the front looks good, make sure we can get at the rest.  */
1045         if (!pskb_may_pull(skb, skb->len))
1046                 goto drop;
1047
1048         b = (struct bootp_pkt *)skb_network_header(skb);
1049         h = &b->iph;
1050
1051         /* One reply at a time, please. */
1052         spin_lock(&ic_recv_lock);
1053
1054         /* If we already have a reply, just drop the packet */
1055         if (ic_got_reply)
1056                 goto drop_unlock;
1057
1058         /* Find the ic_device that the packet arrived on */
1059         d = ic_first_dev;
1060         while (d && d->dev != dev)
1061                 d = d->next;
1062         if (!d)
1063                 goto drop_unlock;  /* should never happen */
1064
1065         /* Is it a reply to our BOOTP request? */
1066         if (b->op != BOOTP_REPLY ||
1067             b->xid != d->xid) {
1068                 net_err_ratelimited("DHCP/BOOTP: Reply not for us on %s, op[%x] xid[%x]\n",
1069                                     d->dev->name, b->op, b->xid);
1070                 goto drop_unlock;
1071         }
1072
1073         /* Parse extensions */
1074         if (ext_len >= 4 &&
1075             !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */
1076                 u8 *end = (u8 *) b + ntohs(b->iph.tot_len);
1077                 u8 *ext;
1078
1079 #ifdef IPCONFIG_DHCP
1080                 if (ic_proto_enabled & IC_USE_DHCP) {
1081                         __be32 server_id = NONE;
1082                         int mt = 0;
1083
1084                         ext = &b->exten[4];
1085                         while (ext < end && *ext != 0xff) {
1086                                 u8 *opt = ext++;
1087                                 if (*opt == 0)  /* Padding */
1088                                         continue;
1089                                 ext += *ext + 1;
1090                                 if (ext >= end)
1091                                         break;
1092                                 switch (*opt) {
1093                                 case 53:        /* Message type */
1094                                         if (opt[1])
1095                                                 mt = opt[2];
1096                                         break;
1097                                 case 54:        /* Server ID (IP address) */
1098                                         if (opt[1] >= 4)
1099                                                 memcpy(&server_id, opt + 2, 4);
1100                                         break;
1101                                 }
1102                         }
1103
1104                         pr_debug("DHCP: Got message type %d (%s)\n", mt, d->dev->name);
1105
1106                         switch (mt) {
1107                         case DHCPOFFER:
1108                                 /* While in the process of accepting one offer,
1109                                  * ignore all others.
1110                                  */
1111                                 if (ic_myaddr != NONE)
1112                                         goto drop_unlock;
1113
1114                                 /* Let's accept that offer. */
1115                                 ic_myaddr = b->your_ip;
1116                                 ic_servaddr = server_id;
1117                                 pr_debug("DHCP: Offered address %pI4 by server %pI4\n",
1118                                          &ic_myaddr, &b->iph.saddr);
1119                                 /* The DHCP indicated server address takes
1120                                  * precedence over the bootp header one if
1121                                  * they are different.
1122                                  */
1123                                 if ((server_id != NONE) &&
1124                                     (b->server_ip != server_id))
1125                                         b->server_ip = ic_servaddr;
1126                                 break;
1127
1128                         case DHCPACK:
1129                                 if (memcmp(dev->dev_addr, b->hw_addr, dev->addr_len) != 0)
1130                                         goto drop_unlock;
1131
1132                                 /* Yeah! */
1133                                 break;
1134
1135                         default:
1136                                 /* Urque.  Forget it*/
1137                                 ic_myaddr = NONE;
1138                                 ic_servaddr = NONE;
1139                                 goto drop_unlock;
1140                         }
1141
1142                         ic_dhcp_msgtype = mt;
1143
1144                 }
1145 #endif /* IPCONFIG_DHCP */
1146
1147                 ext = &b->exten[4];
1148                 while (ext < end && *ext != 0xff) {
1149                         u8 *opt = ext++;
1150                         if (*opt == 0)  /* Padding */
1151                                 continue;
1152                         ext += *ext + 1;
1153                         if (ext < end)
1154                                 ic_do_bootp_ext(opt);
1155                 }
1156         }
1157
1158         /* We have a winner! */
1159         ic_dev = d;
1160         ic_myaddr = b->your_ip;
1161         ic_servaddr = b->server_ip;
1162         ic_addrservaddr = b->iph.saddr;
1163         if (ic_gateway == NONE && b->relay_ip)
1164                 ic_gateway = b->relay_ip;
1165         if (ic_nameservers[0] == NONE) {
1166                 ic_nameservers[0] = ic_servaddr;
1167                 ic_nameservers_fallback = 1;
1168         }
1169         ic_got_reply = IC_BOOTP;
1170
1171 drop_unlock:
1172         /* Show's over.  Nothing to see here.  */
1173         spin_unlock(&ic_recv_lock);
1174
1175 drop:
1176         /* Throw the packet out. */
1177         kfree_skb(skb);
1178
1179         return 0;
1180 }
1181
1182
1183 #endif
1184
1185
1186 /*
1187  *      Dynamic IP configuration -- DHCP, BOOTP, RARP.
1188  */
1189
1190 #ifdef IPCONFIG_DYNAMIC
1191
1192 static int __init ic_dynamic(void)
1193 {
1194         int retries;
1195         struct ic_device *d;
1196         unsigned long start_jiffies, timeout, jiff;
1197         int do_bootp = ic_proto_have_if & IC_BOOTP;
1198         int do_rarp = ic_proto_have_if & IC_RARP;
1199
1200         /*
1201          * If none of DHCP/BOOTP/RARP was selected, return with an error.
1202          * This routine gets only called when some pieces of information
1203          * are missing, and without DHCP/BOOTP/RARP we are unable to get it.
1204          */
1205         if (!ic_proto_enabled) {
1206                 pr_err("IP-Config: Incomplete network configuration information\n");
1207                 return -1;
1208         }
1209
1210 #ifdef IPCONFIG_BOOTP
1211         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_BOOTP)
1212                 pr_err("DHCP/BOOTP: No suitable device found\n");
1213 #endif
1214 #ifdef IPCONFIG_RARP
1215         if ((ic_proto_enabled ^ ic_proto_have_if) & IC_RARP)
1216                 pr_err("RARP: No suitable device found\n");
1217 #endif
1218
1219         if (!ic_proto_have_if)
1220                 /* Error message already printed */
1221                 return -1;
1222
1223         /*
1224          * Setup protocols
1225          */
1226 #ifdef IPCONFIG_BOOTP
1227         if (do_bootp)
1228                 ic_bootp_init();
1229 #endif
1230 #ifdef IPCONFIG_RARP
1231         if (do_rarp)
1232                 ic_rarp_init();
1233 #endif
1234
1235         /*
1236          * Send requests and wait, until we get an answer. This loop
1237          * seems to be a terrible waste of CPU time, but actually there is
1238          * only one process running at all, so we don't need to use any
1239          * scheduler functions.
1240          * [Actually we could now, but the nothing else running note still
1241          *  applies.. - AC]
1242          */
1243         pr_notice("Sending %s%s%s requests .",
1244                   do_bootp
1245                   ? ((ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP") : "",
1246                   (do_bootp && do_rarp) ? " and " : "",
1247                   do_rarp ? "RARP" : "");
1248
1249         start_jiffies = jiffies;
1250         d = ic_first_dev;
1251         retries = CONF_SEND_RETRIES;
1252         get_random_bytes(&timeout, sizeof(timeout));
1253         timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned int) CONF_TIMEOUT_RANDOM);
1254         for (;;) {
1255 #ifdef IPCONFIG_BOOTP
1256                 if (do_bootp && (d->able & IC_BOOTP))
1257                         ic_bootp_send_if(d, jiffies - start_jiffies);
1258 #endif
1259 #ifdef IPCONFIG_RARP
1260                 if (do_rarp && (d->able & IC_RARP))
1261                         ic_rarp_send_if(d);
1262 #endif
1263
1264                 if (!d->next) {
1265                         jiff = jiffies + timeout;
1266                         while (time_before(jiffies, jiff) && !ic_got_reply)
1267                                 schedule_timeout_uninterruptible(1);
1268                 }
1269 #ifdef IPCONFIG_DHCP
1270                 /* DHCP isn't done until we get a DHCPACK. */
1271                 if ((ic_got_reply & IC_BOOTP) &&
1272                     (ic_proto_enabled & IC_USE_DHCP) &&
1273                     ic_dhcp_msgtype != DHCPACK) {
1274                         ic_got_reply = 0;
1275                         /* continue on device that got the reply */
1276                         d = ic_dev;
1277                         pr_cont(",");
1278                         continue;
1279                 }
1280 #endif /* IPCONFIG_DHCP */
1281
1282                 if (ic_got_reply) {
1283                         pr_cont(" OK\n");
1284                         break;
1285                 }
1286
1287                 if ((d = d->next))
1288                         continue;
1289
1290                 if (! --retries) {
1291                         pr_cont(" timed out!\n");
1292                         break;
1293                 }
1294
1295                 d = ic_first_dev;
1296
1297                 timeout = timeout CONF_TIMEOUT_MULT;
1298                 if (timeout > CONF_TIMEOUT_MAX)
1299                         timeout = CONF_TIMEOUT_MAX;
1300
1301                 pr_cont(".");
1302         }
1303
1304 #ifdef IPCONFIG_BOOTP
1305         if (do_bootp)
1306                 ic_bootp_cleanup();
1307 #endif
1308 #ifdef IPCONFIG_RARP
1309         if (do_rarp)
1310                 ic_rarp_cleanup();
1311 #endif
1312
1313         if (!ic_got_reply) {
1314                 ic_myaddr = NONE;
1315                 return -1;
1316         }
1317
1318         pr_info("IP-Config: Got %s answer from %pI4, my address is %pI4\n",
1319                 ((ic_got_reply & IC_RARP) ? "RARP"
1320                 : (ic_proto_enabled & IC_USE_DHCP) ? "DHCP" : "BOOTP"),
1321                 &ic_addrservaddr, &ic_myaddr);
1322
1323         return 0;
1324 }
1325
1326 #endif /* IPCONFIG_DYNAMIC */
1327
1328 #ifdef CONFIG_PROC_FS
1329 /* proc_dir_entry for /proc/net/ipconfig */
1330 static struct proc_dir_entry *ipconfig_dir;
1331
1332 /* Name servers: */
1333 static int pnp_seq_show(struct seq_file *seq, void *v)
1334 {
1335         int i;
1336
1337         if (ic_proto_used & IC_PROTO)
1338                 seq_printf(seq, "#PROTO: %s\n",
1339                            (ic_proto_used & IC_RARP) ? "RARP"
1340                            : (ic_proto_used & IC_USE_DHCP) ? "DHCP" : "BOOTP");
1341         else
1342                 seq_puts(seq, "#MANUAL\n");
1343
1344         if (ic_domain[0])
1345                 seq_printf(seq,
1346                            "domain %s\n", ic_domain);
1347         for (i = 0; i < CONF_NAMESERVERS_MAX; i++) {
1348                 if (ic_nameservers[i] != NONE)
1349                         seq_printf(seq, "nameserver %pI4\n",
1350                                    &ic_nameservers[i]);
1351         }
1352         if (ic_servaddr != NONE)
1353                 seq_printf(seq, "bootserver %pI4\n",
1354                            &ic_servaddr);
1355         return 0;
1356 }
1357
1358 /* Create the /proc/net/ipconfig directory */
1359 static int __init ipconfig_proc_net_init(void)
1360 {
1361         ipconfig_dir = proc_net_mkdir(&init_net, "ipconfig", init_net.proc_net);
1362         if (!ipconfig_dir)
1363                 return -ENOMEM;
1364
1365         return 0;
1366 }
1367
1368 /* Create a new file under /proc/net/ipconfig */
1369 static int ipconfig_proc_net_create(const char *name,
1370                                     const struct proc_ops *proc_ops)
1371 {
1372         char *pname;
1373         struct proc_dir_entry *p;
1374
1375         if (!ipconfig_dir)
1376                 return -ENOMEM;
1377
1378         pname = kasprintf(GFP_KERNEL, "%s%s", "ipconfig/", name);
1379         if (!pname)
1380                 return -ENOMEM;
1381
1382         p = proc_create(pname, 0444, init_net.proc_net, proc_ops);
1383         kfree(pname);
1384         if (!p)
1385                 return -ENOMEM;
1386
1387         return 0;
1388 }
1389
1390 /* Write NTP server IP addresses to /proc/net/ipconfig/ntp_servers */
1391 static int ntp_servers_show(struct seq_file *seq, void *v)
1392 {
1393         int i;
1394
1395         for (i = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1396                 if (ic_ntp_servers[i] != NONE)
1397                         seq_printf(seq, "%pI4\n", &ic_ntp_servers[i]);
1398         }
1399         return 0;
1400 }
1401 DEFINE_PROC_SHOW_ATTRIBUTE(ntp_servers);
1402 #endif /* CONFIG_PROC_FS */
1403
1404 /*
1405  *  Extract IP address from the parameter string if needed. Note that we
1406  *  need to have root_server_addr set _before_ IPConfig gets called as it
1407  *  can override it.
1408  */
1409 __be32 __init root_nfs_parse_addr(char *name)
1410 {
1411         __be32 addr;
1412         int octets = 0;
1413         char *cp, *cq;
1414
1415         cp = cq = name;
1416         while (octets < 4) {
1417                 while (*cp >= '0' && *cp <= '9')
1418                         cp++;
1419                 if (cp == cq || cp - cq > 3)
1420                         break;
1421                 if (*cp == '.' || octets == 3)
1422                         octets++;
1423                 if (octets < 4)
1424                         cp++;
1425                 cq = cp;
1426         }
1427         if (octets == 4 && (*cp == ':' || *cp == '\0')) {
1428                 if (*cp == ':')
1429                         *cp++ = '\0';
1430                 addr = in_aton(name);
1431                 memmove(name, cp, strlen(cp) + 1);
1432         } else
1433                 addr = NONE;
1434
1435         return addr;
1436 }
1437
1438 #define DEVICE_WAIT_MAX         12 /* 12 seconds */
1439
1440 static int __init wait_for_devices(void)
1441 {
1442         int i;
1443         bool try_init_devs = true;
1444
1445         for (i = 0; i < DEVICE_WAIT_MAX; i++) {
1446                 struct net_device *dev;
1447                 int found = 0;
1448
1449                 /* make sure deferred device probes are finished */
1450                 wait_for_device_probe();
1451
1452                 rtnl_lock();
1453                 for_each_netdev(&init_net, dev) {
1454                         if (ic_is_init_dev(dev)) {
1455                                 found = 1;
1456                                 break;
1457                         }
1458                 }
1459                 rtnl_unlock();
1460                 if (found)
1461                         return 0;
1462                 if (try_init_devs &&
1463                     (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) {
1464                         try_init_devs = false;
1465                         wait_for_init_devices_probe();
1466                 }
1467                 ssleep(1);
1468         }
1469         return -ENODEV;
1470 }
1471
1472 /*
1473  *      IP Autoconfig dispatcher.
1474  */
1475
1476 static int __init ip_auto_config(void)
1477 {
1478         __be32 addr;
1479 #ifdef IPCONFIG_DYNAMIC
1480         int retries = CONF_OPEN_RETRIES;
1481 #endif
1482         int err;
1483         unsigned int i, count;
1484
1485         /* Initialise all name servers and NTP servers to NONE (but only if the
1486          * "ip=" or "nfsaddrs=" kernel command line parameters weren't decoded,
1487          * otherwise we'll overwrite the IP addresses specified there)
1488          */
1489         if (ic_set_manually == 0) {
1490                 ic_nameservers_predef();
1491                 ic_ntp_servers_predef();
1492         }
1493
1494 #ifdef CONFIG_PROC_FS
1495         proc_create_single("pnp", 0444, init_net.proc_net, pnp_seq_show);
1496
1497         if (ipconfig_proc_net_init() == 0)
1498                 ipconfig_proc_net_create("ntp_servers", &ntp_servers_proc_ops);
1499 #endif /* CONFIG_PROC_FS */
1500
1501         if (!ic_enable)
1502                 return 0;
1503
1504         pr_debug("IP-Config: Entered.\n");
1505 #ifdef IPCONFIG_DYNAMIC
1506  try_try_again:
1507 #endif
1508         /* Wait for devices to appear */
1509         err = wait_for_devices();
1510         if (err)
1511                 return err;
1512
1513         /* Setup all network devices */
1514         err = ic_open_devs();
1515         if (err)
1516                 return err;
1517
1518         /* Give drivers a chance to settle */
1519         msleep(CONF_POST_OPEN);
1520
1521         /*
1522          * If the config information is insufficient (e.g., our IP address or
1523          * IP address of the boot server is missing or we have multiple network
1524          * interfaces and no default was set), use BOOTP or RARP to get the
1525          * missing values.
1526          */
1527         if (ic_myaddr == NONE ||
1528 #if defined(CONFIG_ROOT_NFS) || defined(CONFIG_CIFS_ROOT)
1529             (root_server_addr == NONE &&
1530              ic_servaddr == NONE &&
1531              (ROOT_DEV == Root_NFS || ROOT_DEV == Root_CIFS)) ||
1532 #endif
1533             ic_first_dev->next) {
1534 #ifdef IPCONFIG_DYNAMIC
1535                 if (ic_dynamic() < 0) {
1536                         ic_close_devs();
1537
1538                         /*
1539                          * I don't know why, but sometimes the
1540                          * eepro100 driver (at least) gets upset and
1541                          * doesn't work the first time it's opened.
1542                          * But then if you close it and reopen it, it
1543                          * works just fine.  So we need to try that at
1544                          * least once before giving up.
1545                          *
1546                          * Also, if the root will be NFS-mounted, we
1547                          * have nowhere to go if DHCP fails.  So we
1548                          * just have to keep trying forever.
1549                          *
1550                          *                              -- Chip
1551                          */
1552 #ifdef CONFIG_ROOT_NFS
1553                         if (ROOT_DEV ==  Root_NFS) {
1554                                 pr_err("IP-Config: Retrying forever (NFS root)...\n");
1555                                 goto try_try_again;
1556                         }
1557 #endif
1558 #ifdef CONFIG_CIFS_ROOT
1559                         if (ROOT_DEV == Root_CIFS) {
1560                                 pr_err("IP-Config: Retrying forever (CIFS root)...\n");
1561                                 goto try_try_again;
1562                         }
1563 #endif
1564
1565                         if (--retries) {
1566                                 pr_err("IP-Config: Reopening network devices...\n");
1567                                 goto try_try_again;
1568                         }
1569
1570                         /* Oh, well.  At least we tried. */
1571                         pr_err("IP-Config: Auto-configuration of network failed\n");
1572                         return -1;
1573                 }
1574 #else /* !DYNAMIC */
1575                 pr_err("IP-Config: Incomplete network configuration information\n");
1576                 ic_close_devs();
1577                 return -1;
1578 #endif /* IPCONFIG_DYNAMIC */
1579         } else {
1580                 /* Device selected manually or only one device -> use it */
1581                 ic_dev = ic_first_dev;
1582         }
1583
1584         addr = root_nfs_parse_addr(root_server_path);
1585         if (root_server_addr == NONE)
1586                 root_server_addr = addr;
1587
1588         /*
1589          * Use defaults wherever applicable.
1590          */
1591         if (ic_defaults() < 0)
1592                 return -1;
1593
1594         /*
1595          * Record which protocol was actually used.
1596          */
1597 #ifdef IPCONFIG_DYNAMIC
1598         ic_proto_used = ic_got_reply | (ic_proto_enabled & IC_USE_DHCP);
1599 #endif
1600
1601 #ifndef IPCONFIG_SILENT
1602         /*
1603          * Clue in the operator.
1604          */
1605         pr_info("IP-Config: Complete:\n");
1606
1607         pr_info("     device=%s, hwaddr=%*phC, ipaddr=%pI4, mask=%pI4, gw=%pI4\n",
1608                 ic_dev->dev->name, ic_dev->dev->addr_len, ic_dev->dev->dev_addr,
1609                 &ic_myaddr, &ic_netmask, &ic_gateway);
1610         pr_info("     host=%s, domain=%s, nis-domain=%s\n",
1611                 utsname()->nodename, ic_domain, utsname()->domainname);
1612         pr_info("     bootserver=%pI4, rootserver=%pI4, rootpath=%s",
1613                 &ic_servaddr, &root_server_addr, root_server_path);
1614         if (ic_dev_mtu)
1615                 pr_cont(", mtu=%d", ic_dev_mtu);
1616         /* Name servers (if any): */
1617         for (i = 0, count = 0; i < CONF_NAMESERVERS_MAX; i++) {
1618                 if (ic_nameservers[i] != NONE) {
1619                         if (i == 0)
1620                                 pr_info("     nameserver%u=%pI4",
1621                                         i, &ic_nameservers[i]);
1622                         else
1623                                 pr_cont(", nameserver%u=%pI4",
1624                                         i, &ic_nameservers[i]);
1625
1626                         count++;
1627                 }
1628                 if ((i + 1 == CONF_NAMESERVERS_MAX) && count > 0)
1629                         pr_cont("\n");
1630         }
1631         /* NTP servers (if any): */
1632         for (i = 0, count = 0; i < CONF_NTP_SERVERS_MAX; i++) {
1633                 if (ic_ntp_servers[i] != NONE) {
1634                         if (i == 0)
1635                                 pr_info("     ntpserver%u=%pI4",
1636                                         i, &ic_ntp_servers[i]);
1637                         else
1638                                 pr_cont(", ntpserver%u=%pI4",
1639                                         i, &ic_ntp_servers[i]);
1640
1641                         count++;
1642                 }
1643                 if ((i + 1 == CONF_NTP_SERVERS_MAX) && count > 0)
1644                         pr_cont("\n");
1645         }
1646 #endif /* !SILENT */
1647
1648         /*
1649          * Close all network devices except the device we've
1650          * autoconfigured and set up routes.
1651          */
1652         if (ic_setup_if() < 0 || ic_setup_routes() < 0)
1653                 err = -1;
1654         else
1655                 err = 0;
1656
1657         ic_close_devs();
1658
1659         return err;
1660 }
1661
1662 late_initcall(ip_auto_config);
1663
1664
1665 /*
1666  *  Decode any IP configuration options in the "ip=" or "nfsaddrs=" kernel
1667  *  command line parameter.  See Documentation/admin-guide/nfs/nfsroot.rst.
1668  */
1669 static int __init ic_proto_name(char *name)
1670 {
1671         if (!strcmp(name, "on") || !strcmp(name, "any")) {
1672                 return 1;
1673         }
1674         if (!strcmp(name, "off") || !strcmp(name, "none")) {
1675                 return 0;
1676         }
1677 #ifdef CONFIG_IP_PNP_DHCP
1678         else if (!strncmp(name, "dhcp", 4)) {
1679                 char *client_id;
1680
1681                 ic_proto_enabled &= ~IC_RARP;
1682                 client_id = strstr(name, "dhcp,");
1683                 if (client_id) {
1684                         char *v;
1685
1686                         client_id = client_id + 5;
1687                         v = strchr(client_id, ',');
1688                         if (!v)
1689                                 return 1;
1690                         *v = 0;
1691                         if (kstrtou8(client_id, 0, dhcp_client_identifier))
1692                                 pr_debug("DHCP: Invalid client identifier type\n");
1693                         strncpy(dhcp_client_identifier + 1, v + 1, 251);
1694                         *v = ',';
1695                 }
1696                 return 1;
1697         }
1698 #endif
1699 #ifdef CONFIG_IP_PNP_BOOTP
1700         else if (!strcmp(name, "bootp")) {
1701                 ic_proto_enabled &= ~(IC_RARP | IC_USE_DHCP);
1702                 return 1;
1703         }
1704 #endif
1705 #ifdef CONFIG_IP_PNP_RARP
1706         else if (!strcmp(name, "rarp")) {
1707                 ic_proto_enabled &= ~(IC_BOOTP | IC_USE_DHCP);
1708                 return 1;
1709         }
1710 #endif
1711 #ifdef IPCONFIG_DYNAMIC
1712         else if (!strcmp(name, "both")) {
1713                 ic_proto_enabled &= ~IC_USE_DHCP; /* backward compat :-( */
1714                 return 1;
1715         }
1716 #endif
1717         return 0;
1718 }
1719
1720 static int __init ip_auto_config_setup(char *addrs)
1721 {
1722         char *cp, *ip, *dp;
1723         int num = 0;
1724
1725         ic_set_manually = 1;
1726         ic_enable = 1;
1727
1728         /*
1729          * If any dhcp, bootp etc options are set, leave autoconfig on
1730          * and skip the below static IP processing.
1731          */
1732         if (ic_proto_name(addrs))
1733                 return 1;
1734
1735         /* If no static IP is given, turn off autoconfig and bail.  */
1736         if (*addrs == 0 ||
1737             strcmp(addrs, "off") == 0 ||
1738             strcmp(addrs, "none") == 0) {
1739                 ic_enable = 0;
1740                 return 1;
1741         }
1742
1743         /* Initialise all name servers and NTP servers to NONE */
1744         ic_nameservers_predef();
1745         ic_ntp_servers_predef();
1746
1747         /* Parse string for static IP assignment.  */
1748         ip = addrs;
1749         while (ip && *ip) {
1750                 if ((cp = strchr(ip, ':')))
1751                         *cp++ = '\0';
1752                 if (strlen(ip) > 0) {
1753                         pr_debug("IP-Config: Parameter #%d: `%s'\n", num, ip);
1754                         switch (num) {
1755                         case 0:
1756                                 if ((ic_myaddr = in_aton(ip)) == ANY)
1757                                         ic_myaddr = NONE;
1758                                 break;
1759                         case 1:
1760                                 if ((ic_servaddr = in_aton(ip)) == ANY)
1761                                         ic_servaddr = NONE;
1762                                 break;
1763                         case 2:
1764                                 if ((ic_gateway = in_aton(ip)) == ANY)
1765                                         ic_gateway = NONE;
1766                                 break;
1767                         case 3:
1768                                 if ((ic_netmask = in_aton(ip)) == ANY)
1769                                         ic_netmask = NONE;
1770                                 break;
1771                         case 4:
1772                                 if ((dp = strchr(ip, '.'))) {
1773                                         *dp++ = '\0';
1774                                         strscpy(utsname()->domainname, dp,
1775                                                 sizeof(utsname()->domainname));
1776                                 }
1777                                 strscpy(utsname()->nodename, ip,
1778                                         sizeof(utsname()->nodename));
1779                                 ic_host_name_set = 1;
1780                                 break;
1781                         case 5:
1782                                 strscpy(user_dev_name, ip, sizeof(user_dev_name));
1783                                 break;
1784                         case 6:
1785                                 if (ic_proto_name(ip) == 0 &&
1786                                     ic_myaddr == NONE) {
1787                                         ic_enable = 0;
1788                                 }
1789                                 break;
1790                         case 7:
1791                                 if (CONF_NAMESERVERS_MAX >= 1) {
1792                                         ic_nameservers[0] = in_aton(ip);
1793                                         if (ic_nameservers[0] == ANY)
1794                                                 ic_nameservers[0] = NONE;
1795                                 }
1796                                 break;
1797                         case 8:
1798                                 if (CONF_NAMESERVERS_MAX >= 2) {
1799                                         ic_nameservers[1] = in_aton(ip);
1800                                         if (ic_nameservers[1] == ANY)
1801                                                 ic_nameservers[1] = NONE;
1802                                 }
1803                                 break;
1804                         case 9:
1805                                 if (CONF_NTP_SERVERS_MAX >= 1) {
1806                                         ic_ntp_servers[0] = in_aton(ip);
1807                                         if (ic_ntp_servers[0] == ANY)
1808                                                 ic_ntp_servers[0] = NONE;
1809                                 }
1810                                 break;
1811                         }
1812                 }
1813                 ip = cp;
1814                 num++;
1815         }
1816
1817         return 1;
1818 }
1819 __setup("ip=", ip_auto_config_setup);
1820
1821 static int __init nfsaddrs_config_setup(char *addrs)
1822 {
1823         return ip_auto_config_setup(addrs);
1824 }
1825 __setup("nfsaddrs=", nfsaddrs_config_setup);
1826
1827 static int __init vendor_class_identifier_setup(char *addrs)
1828 {
1829         if (strscpy(vendor_class_identifier, addrs,
1830                     sizeof(vendor_class_identifier))
1831             >= sizeof(vendor_class_identifier))
1832                 pr_warn("DHCP: vendorclass too long, truncated to \"%s\"\n",
1833                         vendor_class_identifier);
1834         return 1;
1835 }
1836 __setup("dhcpclass=", vendor_class_identifier_setup);
1837
1838 static int __init set_carrier_timeout(char *str)
1839 {
1840         ssize_t ret;
1841
1842         if (!str)
1843                 return 0;
1844
1845         ret = kstrtouint(str, 0, &carrier_timeout);
1846         if (ret)
1847                 return 0;
1848
1849         return 1;
1850 }
1851 __setup("carrier_timeout=", set_carrier_timeout);