net/net.c

   1 /*
   2  *      Copied from Linux Monitor (LiMon) - Networking.
   3  *
   4  *      Copyright 1994 - 2000 Neil Russell.
   5  *      (See License)
   6  *      Copyright 2000 Roland Borde
   7  *      Copyright 2000 Paolo Scaffardi
   8  *      Copyright 2000-2002 Wolfgang Denk, wd@denx.de
   9  */
  10
  11 /*
  12  * General Desription:
  13  *
  14  * The user interface supports commands for BOOTP, RARP, and TFTP.
  15  * Also, we support ARP internally. Depending on available data,
  16  * these interact as follows:
  17  *
  18  * BOOTP:
  19  *
  20  *      Prerequisites:  - own ethernet address
  21  *      We want:        - own IP address
  22  *                      - TFTP server IP address
  23  *                      - name of bootfile
  24  *      Next step:      ARP
  25  *
  26  * RARP:
  27  *
  28  *      Prerequisites:  - own ethernet address
  29  *      We want:        - own IP address
  30  *                      - TFTP server IP address
  31  *      Next step:      ARP
  32  *
  33  * ARP:
  34  *
  35  *      Prerequisites:  - own ethernet address
  36  *                      - own IP address
  37  *                      - TFTP server IP address
  38  *      We want:        - TFTP server ethernet address
  39  *      Next step:      TFTP
  40  *
  41  * DHCP:
  42  *
  43  *     Prerequisites:   - own ethernet address
  44  *     We want:         - IP, Netmask, ServerIP, Gateway IP
  45  *                      - bootfilename, lease time
  46  *     Next step:       - TFTP
  47  *
  48  * TFTP:
  49  *
  50  *      Prerequisites:  - own ethernet address
  51  *                      - own IP address
  52  *                      - TFTP server IP address
  53  *                      - TFTP server ethernet address
  54  *                      - name of bootfile (if unknown, we use a default name
  55  *                        derived from our own IP address)
  56  *      We want:        - load the boot file
  57  *      Next step:      none
  58  */
  59
  60
  61 #include <common.h>
  62 #include <watchdog.h>
  63 #include <command.h>
  64 #include <net.h>
  65 #include "bootp.h"
  66 #include "tftp.h"
  67 #include "rarp.h"
  68
  69 #if (CONFIG_COMMANDS & CFG_CMD_NET)
  70
  71 #define ARP_TIMEOUT             5               /* Seconds before trying ARP again */
  72 #ifndef CONFIG_NET_RETRY_COUNT
  73 # define ARP_TIMEOUT_COUNT      5               /* # of timeouts before giving up  */
  74 #else
  75 # define ARP_TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT)
  76 #endif
  77
  78 #if 0
  79 #define ET_DEBUG
  80 #endif
  81
  82 /** BOOTP EXTENTIONS **/
  83
  84 IPaddr_t        NetOurSubnetMask=0;             /* Our subnet mask (0=unknown)  */
  85 IPaddr_t        NetOurGatewayIP=0;              /* Our gateways IP address      */
  86 IPaddr_t        NetOurDNSIP=0;                  /* Our DNS IP address           */
  87 char            NetOurNISDomain[32]={0,};       /* Our NIS domain               */
  88 char            NetOurHostName[32]={0,};        /* Our hostname                 */
  89 char            NetOurRootPath[64]={0,};        /* Our bootpath                 */
  90 ushort          NetBootFileSize=0;              /* Our bootfile size in blocks  */
  91
  92 /** END OF BOOTP EXTENTIONS **/
  93
  94 ulong           NetBootFileXferSize;    /* The actual transferred size of the bootfile (in bytes) */
  95 uchar           NetOurEther[6];         /* Our ethernet address                 */
  96 uchar           NetServerEther[6] =     /* Boot server enet address             */
  97                         { 0, 0, 0, 0, 0, 0 };
  98 IPaddr_t        NetOurIP;               /* Our IP addr (0 = unknown)            */
  99 IPaddr_t        NetServerIP;            /* Our IP addr (0 = unknown)            */
 100 volatile uchar *NetRxPkt;               /* Current receive packet               */
 101 int             NetRxPktLen;            /* Current rx packet length             */
 102 unsigned        NetIPID;                /* IP packet ID                         */
 103 uchar           NetBcastAddr[6] =       /* Ethernet bcast address               */
 104                         { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 105 uchar           NetEtherNullAddr[6] =
 106                         { 0, 0, 0, 0, 0, 0 };
 107 int             NetState;               /* Network loop state                   */
 108 #ifdef CONFIG_NET_MULTI
 109 int             NetRestartWrap = 0;     /* Tried all network devices            */
 110 static int      NetRestarted = 0;       /* Network loop restarted               */
 111 static int      NetDevExists = 0;       /* At least one device configured       */
 112 #endif
 113
 114 char            BootFile[128];          /* Boot File name                       */
 115
 116 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 117 IPaddr_t        NetPingIP;              /* the ip address to ping               */
 118
 119 static void PingStart(void);
 120 #endif
 121
 122 volatile uchar  PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
 123
 124 volatile uchar *NetRxPackets[PKTBUFSRX]; /* Receive packets                     */
 125
 126 static rxhand_f *packetHandler;         /* Current RX packet handler            */
 127 static thand_f *timeHandler;            /* Current timeout handler              */
 128 static ulong    timeStart;              /* Time base value                      */
 129 static ulong    timeDelta;              /* Current timeout value                */
 130 volatile uchar *NetTxPacket = 0;        /* THE transmit packet                  */
 131
 132 static int net_check_prereq (proto_t protocol);
 133
 134 /**********************************************************************/
 135
 136 IPaddr_t        NetArpWaitPacketIP;
 137 IPaddr_t        NetArpWaitReplyIP;
 138 uchar          *NetArpWaitPacketMAC;    /* MAC address of waiting packet's destination  */
 139 uchar          *NetArpWaitTxPacket;     /* THE transmit packet                  */
 140 int             NetArpWaitTxPacketSize;
 141 uchar           NetArpWaitPacketBuf[PKTSIZE_ALIGN + PKTALIGN];
 142 ulong           NetArpWaitTimerStart;
 143 int             NetArpWaitTry;
 144
 145 void ArpRequest(void)
 146 {
 147         int i;
 148         volatile uchar *pkt;
 149         ARP_t * arp;
 150
 151 #ifdef ET_DEBUG
 152         printf("ARP broadcast %d\n", NetArpWaitTry);
 153 #endif
 154         pkt = NetTxPacket;
 155
 156         NetSetEther(pkt, NetBcastAddr, PROT_ARP);
 157         pkt += ETHER_HDR_SIZE;
 158
 159         arp = (ARP_t *)pkt;
 160
 161         arp->ar_hrd = htons(ARP_ETHER);
 162         arp->ar_pro = htons(PROT_IP);
 163         arp->ar_hln = 6;
 164         arp->ar_pln = 4;
 165         arp->ar_op  = htons(ARPOP_REQUEST);
 166
 167         memcpy (&arp->ar_data[0], NetOurEther, 6);      /* source ET addr       */
 168         NetWriteIP((uchar*)&arp->ar_data[6], NetOurIP); /* source IP addr       */
 169         for (i=10; i<16; ++i) {
 170                 arp->ar_data[i] = 0;                    /* dest ET addr = 0     */
 171         }
 172
 173         if((NetArpWaitPacketIP & NetOurSubnetMask) != (NetOurIP & NetOurSubnetMask)) {
 174             if (NetOurGatewayIP == 0) {
 175                 puts ("## Warning: gatewayip needed but not set\n");
 176             }
 177             NetArpWaitReplyIP = NetOurGatewayIP;
 178         } else
 179             NetArpWaitReplyIP = NetArpWaitPacketIP;
 180
 181         NetWriteIP((uchar*)&arp->ar_data[16], NetArpWaitReplyIP);
 182         (void) eth_send(NetTxPacket, ETHER_HDR_SIZE + ARP_HDR_SIZE);
 183 }
 184
 185 void ArpTimeoutCheck(void)
 186 {
 187         ulong t;
 188
 189         if (!NetArpWaitPacketIP)
 190                 return;
 191
 192         t = get_timer(0);
 193
 194         /* check for arp timeout */
 195         if ((t - NetArpWaitTimerStart) > ARP_TIMEOUT * CFG_HZ) {
 196                 NetArpWaitTry++;
 197
 198                 if (NetArpWaitTry >= ARP_TIMEOUT_COUNT) {
 199                         puts ("\nARP Retry count exceeded; starting again\n");
 200                         NetArpWaitTry = 0;
 201                         NetStartAgain();
 202                 } else {
 203                         NetArpWaitTimerStart = t;
 204                         ArpRequest();
 205                 }
 206         }
 207 }
 208
 209 /**********************************************************************/
 210 /*
 211  *      Main network processing loop.
 212  */
 213
 214 int
 215 NetLoop(proto_t protocol)
 216 {
 217         DECLARE_GLOBAL_DATA_PTR;
 218
 219         bd_t *bd = gd->bd;
 220
 221 #ifdef CONFIG_NET_MULTI
 222         NetRestarted = 0;
 223         NetDevExists = 0;
 224 #endif
 225
 226         /* XXX problem with bss workaround */
 227         NetArpWaitPacketMAC = NULL;
 228         NetArpWaitTxPacket = NULL;
 229         NetArpWaitPacketIP = 0;
 230         NetArpWaitReplyIP = 0;
 231         NetArpWaitTxPacket = NULL;
 232         NetTxPacket = NULL;
 233
 234         if (!NetTxPacket) {
 235                 int     i;
 236
 237                 /*
 238                  *      Setup packet buffers, aligned correctly.
 239                  */
 240                 NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
 241                 NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
 242                 for (i = 0; i < PKTBUFSRX; i++) {
 243                         NetRxPackets[i] = NetTxPacket + (i+1)*PKTSIZE_ALIGN;
 244                 }
 245
 246         }
 247
 248         if (!NetArpWaitTxPacket) {
 249                 NetArpWaitTxPacket = &NetArpWaitPacketBuf[0] + (PKTALIGN - 1);
 250                 NetArpWaitTxPacket -= (ulong)NetArpWaitTxPacket % PKTALIGN;
 251                 NetArpWaitTxPacketSize = 0;
 252         }
 253
 254         eth_halt();
 255         if(eth_init(bd) < 0)
 256             return(-1);
 257
 258 restart:
 259 #ifdef CONFIG_NET_MULTI
 260         memcpy (NetOurEther, eth_get_dev()->enetaddr, 6);
 261 #else
 262         memcpy (NetOurEther, bd->bi_enetaddr, 6);
 263 #endif
 264
 265         NetState = NETLOOP_CONTINUE;
 266
 267         /*
 268          *      Start the ball rolling with the given start function.  From
 269          *      here on, this code is a state machine driven by received
 270          *      packets and timer events.
 271          */
 272
 273         switch (protocol) {
 274 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 275         case PING:
 276 #endif
 277         case TFTP:
 278                 NetCopyIP(&NetOurIP, &bd->bi_ip_addr);
 279                 NetOurGatewayIP = getenv_IPaddr ("gatewayip");
 280                 NetOurSubnetMask= getenv_IPaddr ("netmask");
 281
 282                 switch (protocol) {
 283                 case TFTP:
 284                         NetServerIP = getenv_IPaddr ("serverip");
 285                         break;
 286 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 287                 case PING:
 288                         /* nothing */
 289                         break;
 290 #endif
 291                 default:
 292                         break;
 293                 }
 294
 295                 break;
 296         case BOOTP:
 297         case RARP:
 298                 /*
 299                  * initialize our IP addr to 0 in order to accept ANY
 300                  * IP addr assigned to us by the BOOTP / RARP server
 301                  */
 302                 NetOurIP = 0;
 303                 NetServerIP = 0;
 304                 break;
 305         default:
 306                 break;
 307         }
 308
 309         switch (net_check_prereq (protocol)) {
 310         case 1:
 311                 /* network not configured */
 312                 return (-1);
 313
 314 #ifdef CONFIG_NET_MULTI
 315         case 2:
 316                 /* network device not configured */
 317                 break;
 318 #endif /* CONFIG_NET_MULTI */
 319
 320         case 0:
 321 #ifdef CONFIG_NET_MULTI
 322                 NetDevExists = 1;
 323 #endif
 324                 switch (protocol) {
 325                 case TFTP:
 326                         /* always use ARP to get server ethernet address */
 327                         TftpStart();
 328                         break;
 329
 330 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
 331                 case DHCP:
 332                         /* Start with a clean slate... */
 333                         NetOurIP = 0;
 334                         NetServerIP = 0;
 335                         DhcpRequest();          /* Basically same as BOOTP */
 336                         break;
 337 #endif /* CFG_CMD_DHCP */
 338
 339                 case BOOTP:
 340                         BootpTry = 0;
 341                         BootpRequest ();
 342                         break;
 343
 344                 case RARP:
 345                         RarpTry = 0;
 346                         RarpRequest ();
 347                         break;
 348 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 349                 case PING:
 350                         PingStart();
 351                         break;
 352 #endif
 353                 default:
 354                         break;
 355                 }
 356
 357                 NetBootFileXferSize = 0;
 358                 break;
 359         }
 360
 361
 362         /*
 363          *      Main packet reception loop.  Loop receiving packets until
 364          *      someone sets `NetQuit'.
 365          */
 366         for (;;) {
 367                 WATCHDOG_RESET();
 368 #ifdef CONFIG_SHOW_ACTIVITY
 369                 {
 370                         extern void show_activity(int arg);
 371                         show_activity(1);
 372                 }
 373 #endif
 374                 /*
 375                  *      Check the ethernet for a new packet.  The ethernet
 376                  *      receive routine will process it.
 377                  */
 378                         eth_rx();
 379
 380                 /*
 381                  *      Abort if ctrl-c was pressed.
 382                  */
 383                 if (ctrlc()) {
 384                         eth_halt();
 385                         printf("\nAbort\n");
 386                         return (-1);
 387                 }
 388
 389                 ArpTimeoutCheck();
 390
 391                 /*
 392                  *      Check for a timeout, and run the timeout handler
 393                  *      if we have one.
 394                  */
 395                 if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
 396                         thand_f *x;
 397
 398                         x = timeHandler;
 399                         timeHandler = (thand_f *)0;
 400                         (*x)();
 401                 }
 402
 403
 404                 switch (NetState) {
 405
 406                 case NETLOOP_RESTART:
 407 #ifdef CONFIG_NET_MULTI
 408                         NetRestarted = 1;
 409 #endif
 410                         goto restart;
 411
 412                 case NETLOOP_SUCCESS:
 413                         if (NetBootFileXferSize > 0) {
 414                                 char buf[10];
 415                                 printf("Bytes transferred = %ld (%lx hex)\n",
 416                                         NetBootFileXferSize,
 417                                         NetBootFileXferSize);
 418                                 sprintf(buf, "%lx", NetBootFileXferSize);
 419                                 setenv("filesize", buf);
 420                         }
 421                         eth_halt();
 422                         return NetBootFileXferSize;
 423
 424                 case NETLOOP_FAIL:
 425                         return (-1);
 426                 }
 427         }
 428 }
 429
 430 /**********************************************************************/
 431
 432 static void
 433 startAgainTimeout(void)
 434 {
 435         NetState = NETLOOP_RESTART;
 436 }
 437
 438 static void
 439 startAgainHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
 440 {
 441         /* Totally ignore the packet */
 442 }
 443
 444 void
 445 NetStartAgain(void)
 446 {
 447 #ifndef CONFIG_NET_MULTI
 448         NetSetTimeout(10 * CFG_HZ, startAgainTimeout);
 449         NetSetHandler(startAgainHandler);
 450 #else
 451         DECLARE_GLOBAL_DATA_PTR;
 452
 453         eth_halt();
 454         eth_try_another(!NetRestarted);
 455         eth_init(gd->bd);
 456         if (NetRestartWrap)
 457         {
 458                 NetRestartWrap = 0;
 459                 if (NetDevExists)
 460                 {
 461                         NetSetTimeout(10 * CFG_HZ, startAgainTimeout);
 462                         NetSetHandler(startAgainHandler);
 463                 }
 464                 else
 465                 {
 466                         NetState = NETLOOP_FAIL;
 467                 }
 468         }
 469         else
 470         {
 471                 NetState = NETLOOP_RESTART;
 472         }
 473 #endif
 474 }
 475
 476 /**********************************************************************/
 477 /*
 478  *      Miscelaneous bits.
 479  */
 480
 481 void
 482 NetSetHandler(rxhand_f * f)
 483 {
 484         packetHandler = f;
 485 }
 486
 487
 488 void
 489 NetSetTimeout(int iv, thand_f * f)
 490 {
 491         if (iv == 0) {
 492                 timeHandler = (thand_f *)0;
 493         } else {
 494                 timeHandler = f;
 495                 timeStart = get_timer(0);
 496                 timeDelta = iv;
 497         }
 498 }
 499
 500
 501 void
 502 NetSendPacket(volatile uchar * pkt, int len)
 503 {
 504         (void) eth_send(pkt, len);
 505 }
 506
 507 int
 508 NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport, int len)
 509 {
 510         /* convert to new style broadcast */
 511         if (dest == 0)
 512                 dest = 0xFFFFFFFF;
 513
 514         /* if broadcast, make the ether address a broadcast and don't do ARP */
 515         if (dest == 0xFFFFFFFF)
 516                 ether = NetBcastAddr;
 517
 518         /* if MAC address was not discovered yet, save the packet and do an ARP request */
 519         if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
 520
 521 #ifdef ET_DEBUG
 522                 printf("sending ARP for %08lx\n", dest);
 523 #endif
 524
 525                 NetArpWaitPacketIP = dest;
 526                 NetArpWaitPacketMAC = ether;
 527                 NetSetEther (NetArpWaitTxPacket, NetArpWaitPacketMAC, PROT_IP);
 528                 NetSetIP (NetArpWaitTxPacket + ETHER_HDR_SIZE, dest, dport, sport, len);
 529                 memcpy(NetArpWaitTxPacket + ETHER_HDR_SIZE + IP_HDR_SIZE,
 530                         (uchar *)NetTxPacket + ETHER_HDR_SIZE + IP_HDR_SIZE, len);
 531
 532                 /* size of the waiting packet */
 533                 NetArpWaitTxPacketSize = ETHER_HDR_SIZE + IP_HDR_SIZE + len;
 534
 535                 /* and do the ARP request */
 536                 NetArpWaitTry = 1;
 537                 NetArpWaitTimerStart = get_timer(0);
 538                 ArpRequest();
 539                 return 1;       /* waiting */
 540         }
 541
 542 #ifdef ET_DEBUG
 543         printf("sending UDP to %08lx/%02x:%02x:%02x:%02x:%02x:%02x\n",
 544                         dest, ether[0], ether[1], ether[2], ether[3], ether[4], ether[5]);
 545 #endif
 546
 547         NetSetEther (NetTxPacket, ether, PROT_IP);
 548         NetSetIP (NetTxPacket + ETHER_HDR_SIZE, dest, dport, sport, len);
 549         (void) eth_send(NetTxPacket, ETHER_HDR_SIZE + IP_HDR_SIZE + len);
 550
 551         return 0;       /* transmited */
 552 }
 553
 554 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 555 static ushort PingSeqNo;
 556
 557 int PingSend(void)
 558 {
 559         static uchar mac[6];
 560         volatile IP_t *ip;
 561         volatile ushort *s;
 562
 563         /* XXX always send arp request */
 564
 565         memcpy(mac, NetEtherNullAddr, 6);
 566
 567 #ifdef ET_DEBUG
 568         printf("sending ARP for %08lx\n", NetPingIP);
 569 #endif
 570
 571         NetArpWaitPacketIP = NetPingIP;
 572         NetArpWaitPacketMAC = mac;
 573
 574         NetSetEther(NetArpWaitTxPacket, mac, PROT_IP);
 575
 576         ip = (volatile IP_t *)(NetArpWaitTxPacket + ETHER_HDR_SIZE);
 577
 578         /*
 579          *      Construct an IP and ICMP header.  (need to set no fragment bit - XXX)
 580          */
 581         ip->ip_hl_v  = 0x45;            /* IP_HDR_SIZE / 4 (not including UDP) */
 582         ip->ip_tos   = 0;
 583         ip->ip_len   = htons(IP_HDR_SIZE_NO_UDP + 8);
 584         ip->ip_id    = htons(NetIPID++);
 585         ip->ip_off   = htons(0x4000);   /* No fragmentation */
 586         ip->ip_ttl   = 255;
 587         ip->ip_p     = 0x01;            /* ICMP */
 588         ip->ip_sum   = 0;
 589         NetCopyIP((void*)&ip->ip_src, &NetOurIP); /* already in network byte order */
 590         NetCopyIP((void*)&ip->ip_dst, &NetPingIP);         /* - "" - */
 591         ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2);
 592
 593         s = &ip->udp_src;               /* XXX ICMP starts here */
 594         s[0] = htons(0x0800);           /* echo-request, code */
 595         s[1] = 0;                       /* checksum */
 596         s[2] = 0;                       /* identifier */
 597         s[3] = htons(PingSeqNo++);      /* sequence number */
 598         s[1] = ~NetCksum((uchar *)s, 8/2);
 599
 600         /* size of the waiting packet */
 601         NetArpWaitTxPacketSize = ETHER_HDR_SIZE + IP_HDR_SIZE_NO_UDP + 8;
 602
 603         /* and do the ARP request */
 604         NetArpWaitTry = 1;
 605         NetArpWaitTimerStart = get_timer(0);
 606         ArpRequest();
 607         return 1;       /* waiting */
 608 }
 609
 610 static void
 611 PingTimeout (void)
 612 {
 613         eth_halt();
 614         NetState = NETLOOP_FAIL;        /* we did not get the reply */
 615 }
 616
 617 static void
 618 PingHandler (uchar * pkt, unsigned dest, unsigned src, unsigned len)
 619 {
 620         IPaddr_t tmp;
 621         volatile IP_t *ip = (volatile IP_t *)pkt;
 622
 623         tmp = NetReadIP((void *)&ip->ip_src);
 624         if (tmp != NetPingIP)
 625                 return;
 626
 627         NetState = NETLOOP_SUCCESS;
 628 }
 629
 630 static void PingStart(void)
 631 {
 632         NetSetTimeout (10 * CFG_HZ, PingTimeout);
 633         NetSetHandler (PingHandler);
 634
 635         PingSend();
 636 }
 637
 638 #endif
 639
 640 void
 641 NetReceive(volatile uchar * pkt, int len)
 642 {
 643         Ethernet_t *et;
 644         IP_t    *ip;
 645         ARP_t   *arp;
 646         IPaddr_t tmp;
 647         int     x;
 648
 649         NetRxPkt = pkt;
 650         NetRxPktLen = len;
 651         et = (Ethernet_t *)pkt;
 652
 653         x = ntohs(et->et_protlen);
 654
 655         if (x < 1514) {
 656                 /*
 657                  *      Got a 802 packet.  Check the other protocol field.
 658                  */
 659                 x = ntohs(et->et_prot);
 660                 ip = (IP_t *)(pkt + E802_HDR_SIZE);
 661                 len -= E802_HDR_SIZE;
 662         } else {
 663                 ip = (IP_t *)(pkt + ETHER_HDR_SIZE);
 664                 len -= ETHER_HDR_SIZE;
 665         }
 666
 667 #ifdef ET_DEBUG
 668         printf("Receive from protocol 0x%x\n", x);
 669 #endif
 670
 671         switch (x) {
 672
 673         case PROT_ARP:
 674                 /*
 675                  * We have to deal with two types of ARP packets:
 676                  * - REQUEST packets will be answered by sending  our
 677                  *   IP address - if we know it.
 678                  * - REPLY packates are expected only after we asked
 679                  *   for the TFTP server's or the gateway's ethernet
 680                  *   address; so if we receive such a packet, we set
 681                  *   the server ethernet address
 682                  */
 683 #ifdef ET_DEBUG
 684                 printf("Got ARP\n");
 685 #endif
 686                 arp = (ARP_t *)ip;
 687                 if (len < ARP_HDR_SIZE) {
 688                         printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
 689                         return;
 690                 }
 691                 if (ntohs(arp->ar_hrd) != ARP_ETHER) {
 692                         return;
 693                 }
 694                 if (ntohs(arp->ar_pro) != PROT_IP) {
 695                         return;
 696                 }
 697                 if (arp->ar_hln != 6) {
 698                         return;
 699                 }
 700                 if (arp->ar_pln != 4) {
 701                         return;
 702                 }
 703
 704                 if (NetOurIP == 0) {
 705                         return;
 706                 }
 707
 708                 if (NetReadIP(&arp->ar_data[16]) != NetOurIP) {
 709                         return;
 710                 }
 711
 712                 switch (ntohs(arp->ar_op)) {
 713                 case ARPOP_REQUEST:             /* reply with our IP address    */
 714 #ifdef ET_DEBUG
 715                         printf("Got ARP REQUEST, return our IP\n");
 716 #endif
 717                         NetSetEther((uchar *)et, et->et_src, PROT_ARP);
 718                         arp->ar_op = htons(ARPOP_REPLY);
 719                         memcpy   (&arp->ar_data[10], &arp->ar_data[0], 6);
 720                         NetCopyIP(&arp->ar_data[16], &arp->ar_data[6]);
 721                         memcpy   (&arp->ar_data[ 0], NetOurEther, 6);
 722                         NetCopyIP(&arp->ar_data[ 6], &NetOurIP);
 723                         (void) eth_send((uchar *)et, ((uchar *)arp-pkt) + ARP_HDR_SIZE);
 724                         return;
 725
 726                 case ARPOP_REPLY:               /* arp reply */
 727                         /* are we waiting for a reply */
 728                         if (!NetArpWaitPacketIP || !NetArpWaitPacketMAC)
 729                                 break;
 730 #ifdef ET_DEBUG
 731                         printf("Got ARP REPLY, set server/gtwy eth addr (%02x:%02x:%02x:%02x:%02x:%02x)\n",
 732                                 arp->ar_data[0], arp->ar_data[1],
 733                                 arp->ar_data[2], arp->ar_data[3],
 734                                 arp->ar_data[4], arp->ar_data[5]);
 735 #endif
 736
 737                         tmp = NetReadIP(&arp->ar_data[6]);
 738
 739                         /* matched waiting packet's address */
 740                         if (tmp == NetArpWaitReplyIP) {
 741 #ifdef ET_DEBUG
 742                                 printf("Got it\n");
 743 #endif
 744                                 /* save address for later use */
 745                                 memcpy(NetArpWaitPacketMAC, &arp->ar_data[0], 6);
 746
 747                                 /* modify header, and transmit it */
 748                                 memcpy(((Ethernet_t *)NetArpWaitTxPacket)->et_dest, NetArpWaitPacketMAC, 6);
 749                                 (void) eth_send(NetArpWaitTxPacket, NetArpWaitTxPacketSize);
 750
 751                                 /* no arp request pending now */
 752                                 NetArpWaitPacketIP = 0;
 753                                 NetArpWaitTxPacketSize = 0;
 754                                 NetArpWaitPacketMAC = NULL;
 755
 756                         }
 757                         return;
 758                 default:
 759 #ifdef ET_DEBUG
 760                         printf("Unexpected ARP opcode 0x%x\n", ntohs(arp->ar_op));
 761 #endif
 762                         return;
 763                 }
 764
 765         case PROT_RARP:
 766 #ifdef ET_DEBUG
 767                 printf("Got RARP\n");
 768 #endif
 769                 arp = (ARP_t *)ip;
 770                 if (len < ARP_HDR_SIZE) {
 771                         printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
 772                         return;
 773                 }
 774
 775                 if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
 776                         (ntohs(arp->ar_hrd) != ARP_ETHER)   ||
 777                         (ntohs(arp->ar_pro) != PROT_IP)     ||
 778                         (arp->ar_hln != 6) || (arp->ar_pln != 4)) {
 779
 780                         printf("invalid RARP header\n");
 781                 } else {
 782                         NetCopyIP(&NetOurIP,    &arp->ar_data[16]);
 783                         NetCopyIP(&NetServerIP, &arp->ar_data[ 6]);
 784                         memcpy (NetServerEther, &arp->ar_data[ 0], 6);
 785
 786                         (*packetHandler)(0,0,0,0);
 787                 }
 788                 break;
 789
 790         case PROT_IP:
 791 #ifdef ET_DEBUG
 792                 printf("Got IP\n");
 793 #endif
 794                 if (len < IP_HDR_SIZE) {
 795                         debug ("len bad %d < %d\n", len, IP_HDR_SIZE);
 796                         return;
 797                 }
 798                 if (len < ntohs(ip->ip_len)) {
 799                         printf("len bad %d < %d\n", len, ntohs(ip->ip_len));
 800                         return;
 801                 }
 802                 len = ntohs(ip->ip_len);
 803 #ifdef ET_DEBUG
 804                 printf("len=%d, v=%02x\n", len, ip->ip_hl_v & 0xff);
 805 #endif
 806                 if ((ip->ip_hl_v & 0xf0) != 0x40) {
 807                         return;
 808                 }
 809                 if (ip->ip_off & htons(0x1fff)) { /* Can't deal w/ fragments */
 810                         return;
 811                 }
 812                 if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2)) {
 813                         printf("checksum bad\n");
 814                         return;
 815                 }
 816                 tmp = NetReadIP(&ip->ip_dst);
 817                 if (NetOurIP && tmp != NetOurIP && tmp != 0xFFFFFFFF) {
 818                         return;
 819                 }
 820                 /*
 821                  * watch for ICMP host redirects
 822                  *
 823                  * There is no real handler code (yet). We just watch
 824                  * for ICMP host redirect messages. In case anybody
 825                  * sees these messages: please contact me
 826                  * (wd@denx.de), or - even better - send me the
 827                  * necessary fixes :-)
 828                  *
 829                  * Note: in all cases where I have seen this so far
 830                  * it was a problem with the router configuration,
 831                  * for instance when a router was configured in the
 832                  * BOOTP reply, but the TFTP server was on the same
 833                  * subnet. So this is probably a warning that your
 834                  * configuration might be wrong. But I'm not really
 835                  * sure if there aren't any other situations.
 836                  */
 837                 if (ip->ip_p == IPPROTO_ICMP) {
 838                         ICMP_t *icmph = (ICMP_t *)&(ip->udp_src);
 839
 840                         switch (icmph->type) {
 841                         case ICMP_REDIRECT:
 842                         if (icmph->code != ICMP_REDIR_HOST)
 843                                 return;
 844                         puts (" ICMP Host Redirect to ");
 845                         print_IPaddr(icmph->un.gateway);
 846                         putc(' ');
 847                                 break;
 848 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 849                         case ICMP_ECHO_REPLY:
 850                                 /*
 851                                  *      IP header OK.  Pass the packet to the current handler.
 852                                  */
 853                                 /* XXX point to ip packet */
 854                                 (*packetHandler)((uchar *)ip, 0, 0, 0);
 855                                 break;
 856 #endif
 857                         default:
 858                                 return;
 859                         }
 860                 } else if (ip->ip_p != IPPROTO_UDP) {   /* Only UDP packets */
 861                         return;
 862                 }
 863
 864                 /*
 865                  *      IP header OK.  Pass the packet to the current handler.
 866                  */
 867                 (*packetHandler)((uchar *)ip +IP_HDR_SIZE,
 868                                                 ntohs(ip->udp_dst),
 869                                                 ntohs(ip->udp_src),
 870                                                 ntohs(ip->udp_len) - 8);
 871
 872                 break;
 873         }
 874 }
 875
 876
 877 /**********************************************************************/
 878
 879 static int net_check_prereq (proto_t protocol)
 880 {
 881         switch (protocol) {
 882                         /* Fall through */
 883 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 884         case PING:
 885                         if (NetPingIP == 0) {
 886                                 puts ("*** ERROR: ping address not given\n");
 887                                 return (1);
 888                         }
 889                         goto common;
 890 #endif
 891         case TFTP:
 892                         if (NetServerIP == 0) {
 893                                 puts ("*** ERROR: `serverip' not set\n");
 894                                 return (1);
 895                         }
 896
 897 #if (CONFIG_COMMANDS & CFG_CMD_PING)
 898                 common:
 899 #endif
 900
 901                         if (NetOurIP == 0) {
 902                                 puts ("*** ERROR: `ipaddr' not set\n");
 903                                 return (1);
 904                         }
 905                         /* Fall through */
 906
 907         case DHCP:
 908         case RARP:
 909         case BOOTP:
 910                         if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
 911 #ifdef CONFIG_NET_MULTI
 912                             extern int eth_get_dev_index (void);
 913                             int num = eth_get_dev_index();
 914
 915                             switch (num) {
 916                             case -1:
 917                                 puts ("*** ERROR: No ethernet found.\n");
 918                                 return (1);
 919                             case 0:
 920                                 puts ("*** ERROR: `ethaddr' not set\n");
 921                                 break;
 922                             default:
 923                                 printf ("*** ERROR: `eth%daddr' not set\n",
 924                                         num);
 925                                 break;
 926                             }
 927
 928                             NetStartAgain ();
 929                             return (2);
 930 #else
 931                             puts ("*** ERROR: `ethaddr' not set\n");
 932                             return (1);
 933 #endif
 934                         }
 935                         /* Fall through */
 936                 default:
 937                         return(0);
 938         }
 939         return (0);     /* OK */
 940 }
 941 /**********************************************************************/
 942
 943 int
 944 NetCksumOk(uchar * ptr, int len)
 945 {
 946         return !((NetCksum(ptr, len) + 1) & 0xfffe);
 947 }
 948
 949
 950 unsigned
 951 NetCksum(uchar * ptr, int len)
 952 {
 953         ulong   xsum;
 954
 955         xsum = 0;
 956         while (len-- > 0)
 957                 xsum += *((ushort *)ptr)++;
 958         xsum = (xsum & 0xffff) + (xsum >> 16);
 959         xsum = (xsum & 0xffff) + (xsum >> 16);
 960         return (xsum & 0xffff);
 961 }
 962
 963
 964 void
 965 NetSetEther(volatile uchar * xet, uchar * addr, uint prot)
 966 {
 967         Ethernet_t *et = (Ethernet_t *)xet;
 968
 969         memcpy (et->et_dest, addr, 6);
 970         memcpy (et->et_src, NetOurEther, 6);
 971         et->et_protlen = htons(prot);
 972 }
 973
 974
 975 void
 976 NetSetIP(volatile uchar * xip, IPaddr_t dest, int dport, int sport, int len)
 977 {
 978         volatile IP_t *ip = (IP_t *)xip;
 979
 980         /*
 981          *      If the data is an odd number of bytes, zero the
 982          *      byte after the last byte so that the checksum
 983          *      will work.
 984          */
 985         if (len & 1)
 986                 xip[IP_HDR_SIZE + len] = 0;
 987
 988         /*
 989          *      Construct an IP and UDP header.
 990                         (need to set no fragment bit - XXX)
 991          */
 992         ip->ip_hl_v  = 0x45;            /* IP_HDR_SIZE / 4 (not including UDP) */
 993         ip->ip_tos   = 0;
 994         ip->ip_len   = htons(IP_HDR_SIZE + len);
 995         ip->ip_id    = htons(NetIPID++);
 996         ip->ip_off   = htons(0x4000);   /* No fragmentation */
 997         ip->ip_ttl   = 255;
 998         ip->ip_p     = 17;              /* UDP */
 999         ip->ip_sum   = 0;
1000         NetCopyIP((void*)&ip->ip_src, &NetOurIP); /* already in network byte order */
1001         NetCopyIP((void*)&ip->ip_dst, &dest);      /* - "" - */
1002         ip->udp_src  = htons(sport);
1003         ip->udp_dst  = htons(dport);
1004         ip->udp_len  = htons(8 + len);
1005         ip->udp_xsum = 0;
1006         ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2);
1007 }
1008
1009 void copy_filename (uchar *dst, uchar *src, int size)
1010 {
1011         if (*src && (*src == '"')) {
1012                 ++src;
1013                 --size;
1014         }
1015
1016         while ((--size > 0) && *src && (*src != '"')) {
1017                 *dst++ = *src++;
1018         }
1019         *dst = '\0';
1020 }
1021
1022 #endif /* CFG_CMD_NET */
1023
1024 void ip_to_string (IPaddr_t x, char *s)
1025 {
1026     x = ntohl(x);
1027     sprintf (s,"%d.%d.%d.%d",
1028         (int)((x >> 24) & 0xff),
1029         (int)((x >> 16) & 0xff),
1030         (int)((x >>  8) & 0xff),
1031         (int)((x >>  0) & 0xff)
1032     );
1033 }
1034
1035 IPaddr_t string_to_ip(char *s)
1036 {
1037         IPaddr_t addr;
1038         char *e;
1039         int i;
1040
1041         if (s == NULL)
1042                 return(0);
1043
1044         for (addr=0, i=0; i<4; ++i) {
1045                 ulong val = s ? simple_strtoul(s, &e, 10) : 0;
1046                 addr <<= 8;
1047                 addr |= (val & 0xFF);
1048                 if (s) {
1049                         s = (*e) ? e+1 : e;
1050                 }
1051         }
1052
1053         return (htonl(addr));
1054 }
1055
1056 void print_IPaddr (IPaddr_t x)
1057 {
1058     char tmp[16];
1059
1060     ip_to_string(x, tmp);
1061
1062     puts(tmp);
1063 }
1064
1065 IPaddr_t getenv_IPaddr (char *var)
1066 {
1067         return (string_to_ip(getenv(var)));
1068 }