net/tftp.c

   1 /*
   2  * Copyright 1994, 1995, 2000 Neil Russell.
   3  * (See License)
   4  * Copyright 2000, 2001 DENX Software Engineering, Wolfgang Denk, wd@denx.de
   5  */
   6
   7 #include <common.h>
   8 #include <command.h>
   9 #include <net.h>
  10 #include "tftp.h"
  11 #include "bootp.h"
  12
  13 /* Well known TFTP port # */
  14 #define WELL_KNOWN_PORT 69
  15 /* Millisecs to timeout for lost pkt */
  16 #define TIMEOUT         5000UL
  17 #ifndef CONFIG_NET_RETRY_COUNT
  18 /* # of timeouts before giving up */
  19 # define TIMEOUT_COUNT  10
  20 #else
  21 # define TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT * 2)
  22 #endif
  23 /* Number of "loading" hashes per line (for checking the image size) */
  24 #define HASHES_PER_LINE 65
  25
  26 /*
  27  *      TFTP operations.
  28  */
  29 #define TFTP_RRQ        1
  30 #define TFTP_WRQ        2
  31 #define TFTP_DATA       3
  32 #define TFTP_ACK        4
  33 #define TFTP_ERROR      5
  34 #define TFTP_OACK       6
  35
  36 static ulong TftpTimeoutMSecs = TIMEOUT;
  37 static int TftpTimeoutCountMax = TIMEOUT_COUNT;
  38
  39 /*
  40  * These globals govern the timeout behavior when attempting a connection to a
  41  * TFTP server. TftpRRQTimeoutMSecs specifies the number of milliseconds to
  42  * wait for the server to respond to initial connection. Second global,
  43  * TftpRRQTimeoutCountMax, gives the number of such connection retries.
  44  * TftpRRQTimeoutCountMax must be non-negative and TftpRRQTimeoutMSecs must be
  45  * positive. The globals are meant to be set (and restored) by code needing
  46  * non-standard timeout behavior when initiating a TFTP transfer.
  47  */
  48 ulong TftpRRQTimeoutMSecs = TIMEOUT;
  49 int TftpRRQTimeoutCountMax = TIMEOUT_COUNT;
  50
  51 enum {
  52         TFTP_ERR_UNDEFINED           = 0,
  53         TFTP_ERR_FILE_NOT_FOUND      = 1,
  54         TFTP_ERR_ACCESS_DENIED       = 2,
  55         TFTP_ERR_DISK_FULL           = 3,
  56         TFTP_ERR_UNEXPECTED_OPCODE   = 4,
  57         TFTP_ERR_UNKNOWN_TRANSFER_ID  = 5,
  58         TFTP_ERR_FILE_ALREADY_EXISTS = 6,
  59 };
  60
  61 static IPaddr_t TftpServerIP;
  62 /* The UDP port at their end */
  63 static int      TftpServerPort;
  64 /* The UDP port at our end */
  65 static int      TftpOurPort;
  66 static int      TftpTimeoutCount;
  67 /* packet sequence number */
  68 static ulong    TftpBlock;
  69 /* last packet sequence number received */
  70 static ulong    TftpLastBlock;
  71 /* count of sequence number wraparounds */
  72 static ulong    TftpBlockWrap;
  73 /* memory offset due to wrapping */
  74 static ulong    TftpBlockWrapOffset;
  75 static int      TftpState;
  76 #ifdef CONFIG_TFTP_TSIZE
  77 /* The file size reported by the server */
  78 static int      TftpTsize;
  79 /* The number of hashes we printed */
  80 static short    TftpNumchars;
  81 #endif
  82
  83 #define STATE_RRQ       1
  84 #define STATE_DATA      2
  85 #define STATE_TOO_LARGE 3
  86 #define STATE_BAD_MAGIC 4
  87 #define STATE_OACK      5
  88
  89 /* default TFTP block size */
  90 #define TFTP_BLOCK_SIZE         512
  91 /* sequence number is 16 bit */
  92 #define TFTP_SEQUENCE_SIZE      ((ulong)(1<<16))
  93
  94 #define DEFAULT_NAME_LEN        (8 + 4 + 1)
  95 static char default_filename[DEFAULT_NAME_LEN];
  96
  97 #ifndef CONFIG_TFTP_FILE_NAME_MAX_LEN
  98 #define MAX_LEN 128
  99 #else
 100 #define MAX_LEN CONFIG_TFTP_FILE_NAME_MAX_LEN
 101 #endif
 102
 103 static char tftp_filename[MAX_LEN];
 104
 105 #ifdef CONFIG_SYS_DIRECT_FLASH_TFTP
 106 extern flash_info_t flash_info[];
 107 #endif
 108
 109 /* 512 is poor choice for ethernet, MTU is typically 1500.
 110  * Minus eth.hdrs thats 1468.  Can get 2x better throughput with
 111  * almost-MTU block sizes.  At least try... fall back to 512 if need be.
 112  * (but those using CONFIG_IP_DEFRAG may want to set a larger block in cfg file)
 113  */
 114 #ifdef CONFIG_TFTP_BLOCKSIZE
 115 #define TFTP_MTU_BLOCKSIZE CONFIG_TFTP_BLOCKSIZE
 116 #else
 117 #define TFTP_MTU_BLOCKSIZE 1468
 118 #endif
 119
 120 static unsigned short TftpBlkSize = TFTP_BLOCK_SIZE;
 121 static unsigned short TftpBlkSizeOption = TFTP_MTU_BLOCKSIZE;
 122
 123 #ifdef CONFIG_MCAST_TFTP
 124 #include <malloc.h>
 125 #define MTFTP_BITMAPSIZE        0x1000
 126 static unsigned *Bitmap;
 127 static int PrevBitmapHole, Mapsize = MTFTP_BITMAPSIZE;
 128 static uchar ProhibitMcast = 0, MasterClient = 0;
 129 static uchar Multicast = 0;
 130 extern IPaddr_t Mcast_addr;
 131 static int Mcast_port;
 132 static ulong TftpEndingBlock; /* can get 'last' block before done..*/
 133
 134 static void parse_multicast_oack(char *pkt, int len);
 135
 136 static void
 137 mcast_cleanup(void)
 138 {
 139         if (Mcast_addr) eth_mcast_join(Mcast_addr, 0);
 140         if (Bitmap) free(Bitmap);
 141         Bitmap = NULL;
 142         Mcast_addr = Multicast = Mcast_port = 0;
 143         TftpEndingBlock = -1;
 144 }
 145
 146 #endif  /* CONFIG_MCAST_TFTP */
 147
 148 static __inline__ void
 149 store_block(unsigned block, uchar *src, unsigned len)
 150 {
 151         ulong offset = block * TftpBlkSize + TftpBlockWrapOffset;
 152         ulong newsize = offset + len;
 153 #ifdef CONFIG_SYS_DIRECT_FLASH_TFTP
 154         int i, rc = 0;
 155
 156         for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; i++) {
 157                 /* start address in flash? */
 158                 if (flash_info[i].flash_id == FLASH_UNKNOWN)
 159                         continue;
 160                 if (load_addr + offset >= flash_info[i].start[0]) {
 161                         rc = 1;
 162                         break;
 163                 }
 164         }
 165
 166         if (rc) { /* Flash is destination for this packet */
 167                 rc = flash_write((char *)src, (ulong)(load_addr+offset), len);
 168                 if (rc) {
 169                         flash_perror(rc);
 170                         NetState = NETLOOP_FAIL;
 171                         return;
 172                 }
 173         }
 174         else
 175 #endif /* CONFIG_SYS_DIRECT_FLASH_TFTP */
 176         {
 177                 (void)memcpy((void *)(load_addr + offset), src, len);
 178         }
 179 #ifdef CONFIG_MCAST_TFTP
 180         if (Multicast)
 181                 ext2_set_bit(block, Bitmap);
 182 #endif
 183
 184         if (NetBootFileXferSize < newsize)
 185                 NetBootFileXferSize = newsize;
 186 }
 187
 188 static void TftpSend(void);
 189 static void TftpTimeout(void);
 190
 191 /**********************************************************************/
 192
 193 static void
 194 TftpSend(void)
 195 {
 196         volatile uchar *pkt;
 197         volatile uchar *xp;
 198         int             len = 0;
 199         volatile ushort *s;
 200
 201 #ifdef CONFIG_MCAST_TFTP
 202         /* Multicast TFTP.. non-MasterClients do not ACK data. */
 203         if (Multicast
 204          && (TftpState == STATE_DATA)
 205          && (MasterClient == 0))
 206                 return;
 207 #endif
 208         /*
 209          *      We will always be sending some sort of packet, so
 210          *      cobble together the packet headers now.
 211          */
 212         pkt = NetTxPacket + NetEthHdrSize() + IP_HDR_SIZE;
 213
 214         switch (TftpState) {
 215
 216         case STATE_RRQ:
 217                 xp = pkt;
 218                 s = (ushort *)pkt;
 219                 *s++ = htons(TFTP_RRQ);
 220                 pkt = (uchar *)s;
 221                 strcpy((char *)pkt, tftp_filename);
 222                 pkt += strlen(tftp_filename) + 1;
 223                 strcpy((char *)pkt, "octet");
 224                 pkt += 5 /*strlen("octet")*/ + 1;
 225                 strcpy((char *)pkt, "timeout");
 226                 pkt += 7 /*strlen("timeout")*/ + 1;
 227                 sprintf((char *)pkt, "%lu", TftpTimeoutMSecs / 1000);
 228                 debug("send option \"timeout %s\"\n", (char *)pkt);
 229                 pkt += strlen((char *)pkt) + 1;
 230 #ifdef CONFIG_TFTP_TSIZE
 231                 memcpy((char *)pkt, "tsize\0000\0", 8);
 232                 pkt += 8;
 233 #endif
 234                 /* try for more effic. blk size */
 235                 pkt += sprintf((char *)pkt, "blksize%c%d%c",
 236                                 0, TftpBlkSizeOption, 0);
 237 #ifdef CONFIG_MCAST_TFTP
 238                 /* Check all preconditions before even trying the option */
 239                 if (!ProhibitMcast
 240                  && (Bitmap = malloc(Mapsize))
 241                  && eth_get_dev()->mcast) {
 242                         free(Bitmap);
 243                         Bitmap = NULL;
 244                         pkt += sprintf((char *)pkt, "multicast%c%c", 0, 0);
 245                 }
 246 #endif /* CONFIG_MCAST_TFTP */
 247                 len = pkt - xp;
 248                 break;
 249
 250         case STATE_OACK:
 251 #ifdef CONFIG_MCAST_TFTP
 252                 /* My turn!  Start at where I need blocks I missed.*/
 253                 if (Multicast)
 254                         TftpBlock = ext2_find_next_zero_bit(Bitmap,
 255                                                             (Mapsize*8), 0);
 256                 /*..falling..*/
 257 #endif
 258         case STATE_DATA:
 259                 xp = pkt;
 260                 s = (ushort *)pkt;
 261                 *s++ = htons(TFTP_ACK);
 262                 *s++ = htons(TftpBlock);
 263                 pkt = (uchar *)s;
 264                 len = pkt - xp;
 265                 break;
 266
 267         case STATE_TOO_LARGE:
 268                 xp = pkt;
 269                 s = (ushort *)pkt;
 270                 *s++ = htons(TFTP_ERROR);
 271                 *s++ = htons(3);
 272                 pkt = (uchar *)s;
 273                 strcpy((char *)pkt, "File too large");
 274                 pkt += 14 /*strlen("File too large")*/ + 1;
 275                 len = pkt - xp;
 276                 break;
 277
 278         case STATE_BAD_MAGIC:
 279                 xp = pkt;
 280                 s = (ushort *)pkt;
 281                 *s++ = htons(TFTP_ERROR);
 282                 *s++ = htons(2);
 283                 pkt = (uchar *)s;
 284                 strcpy((char *)pkt, "File has bad magic");
 285                 pkt += 18 /*strlen("File has bad magic")*/ + 1;
 286                 len = pkt - xp;
 287                 break;
 288         }
 289
 290         NetSendUDPPacket(NetServerEther, TftpServerIP, TftpServerPort,
 291                          TftpOurPort, len);
 292 }
 293
 294
 295 static void
 296 TftpHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
 297             unsigned len)
 298 {
 299         ushort proto;
 300         ushort *s;
 301         int i;
 302
 303         if (dest != TftpOurPort) {
 304 #ifdef CONFIG_MCAST_TFTP
 305                 if (Multicast
 306                  && (!Mcast_port || (dest != Mcast_port)))
 307 #endif
 308                 return;
 309         }
 310         if (TftpState != STATE_RRQ && src != TftpServerPort)
 311                 return;
 312
 313         if (len < 2)
 314                 return;
 315         len -= 2;
 316         /* warning: don't use increment (++) in ntohs() macros!! */
 317         s = (ushort *)pkt;
 318         proto = *s++;
 319         pkt = (uchar *)s;
 320         switch (ntohs(proto)) {
 321
 322         case TFTP_RRQ:
 323         case TFTP_WRQ:
 324         case TFTP_ACK:
 325                 break;
 326         default:
 327                 break;
 328
 329         case TFTP_OACK:
 330                 debug("Got OACK: %s %s\n",
 331                         pkt,
 332                         pkt + strlen((char *)pkt) + 1);
 333                 TftpState = STATE_OACK;
 334                 TftpServerPort = src;
 335                 /*
 336                  * Check for 'blksize' option.
 337                  * Careful: "i" is signed, "len" is unsigned, thus
 338                  * something like "len-8" may give a *huge* number
 339                  */
 340                 for (i = 0; i+8 < len; i++) {
 341                         if (strcmp((char *)pkt+i, "blksize") == 0) {
 342                                 TftpBlkSize = (unsigned short)
 343                                         simple_strtoul((char *)pkt+i+8, NULL,
 344                                                        10);
 345                                 debug("Blocksize ack: %s, %d\n",
 346                                         (char *)pkt+i+8, TftpBlkSize);
 347                         }
 348 #ifdef CONFIG_TFTP_TSIZE
 349                         if (strcmp((char *)pkt+i, "tsize") == 0) {
 350                                 TftpTsize = simple_strtoul((char *)pkt+i+6,
 351                                                            NULL, 10);
 352                                 debug("size = %s, %d\n",
 353                                          (char *)pkt+i+6, TftpTsize);
 354                         }
 355 #endif
 356                 }
 357 #ifdef CONFIG_MCAST_TFTP
 358                 parse_multicast_oack((char *)pkt, len-1);
 359                 if ((Multicast) && (!MasterClient))
 360                         TftpState = STATE_DATA; /* passive.. */
 361                 else
 362 #endif
 363                 TftpSend(); /* Send ACK */
 364                 break;
 365         case TFTP_DATA:
 366                 if (len < 2)
 367                         return;
 368                 len -= 2;
 369                 TftpBlock = ntohs(*(ushort *)pkt);
 370
 371                 /*
 372                  * RFC1350 specifies that the first data packet will
 373                  * have sequence number 1. If we receive a sequence
 374                  * number of 0 this means that there was a wrap
 375                  * around of the (16 bit) counter.
 376                  */
 377                 if (TftpBlock == 0) {
 378                         TftpBlockWrap++;
 379                         TftpBlockWrapOffset +=
 380                                 TftpBlkSize * TFTP_SEQUENCE_SIZE;
 381                         printf("\n\t %lu MB received\n\t ",
 382                                 TftpBlockWrapOffset>>20);
 383                 }
 384 #ifdef CONFIG_TFTP_TSIZE
 385                 else if (TftpTsize) {
 386                         while (TftpNumchars <
 387                                NetBootFileXferSize * 50 / TftpTsize) {
 388                                 putc('#');
 389                                 TftpNumchars++;
 390                         }
 391                 }
 392 #endif
 393                 else {
 394                         if (((TftpBlock - 1) % 10) == 0)
 395                                 putc('#');
 396                         else if ((TftpBlock % (10 * HASHES_PER_LINE)) == 0)
 397                                 puts("\n\t ");
 398                 }
 399
 400                 if (TftpState == STATE_RRQ)
 401                         debug("Server did not acknowledge timeout option!\n");
 402
 403                 if (TftpState == STATE_RRQ || TftpState == STATE_OACK) {
 404                         /* first block received */
 405                         TftpState = STATE_DATA;
 406                         TftpServerPort = src;
 407                         TftpLastBlock = 0;
 408                         TftpBlockWrap = 0;
 409                         TftpBlockWrapOffset = 0;
 410
 411 #ifdef CONFIG_MCAST_TFTP
 412                         if (Multicast) { /* start!=1 common if mcast */
 413                                 TftpLastBlock = TftpBlock - 1;
 414                         } else
 415 #endif
 416                         if (TftpBlock != 1) {   /* Assertion */
 417                                 printf("\nTFTP error: "
 418                                        "First block is not block 1 (%ld)\n"
 419                                        "Starting again\n\n",
 420                                         TftpBlock);
 421                                 NetStartAgain();
 422                                 break;
 423                         }
 424                 }
 425
 426                 if (TftpBlock == TftpLastBlock) {
 427                         /*
 428                          *      Same block again; ignore it.
 429                          */
 430                         break;
 431                 }
 432
 433                 TftpLastBlock = TftpBlock;
 434                 TftpTimeoutCountMax = TIMEOUT_COUNT;
 435                 NetSetTimeout(TftpTimeoutMSecs, TftpTimeout);
 436
 437                 store_block(TftpBlock - 1, pkt + 2, len);
 438
 439                 /*
 440                  *      Acknoledge the block just received, which will prompt
 441                  *      the server for the next one.
 442                  */
 443 #ifdef CONFIG_MCAST_TFTP
 444                 /* if I am the MasterClient, actively calculate what my next
 445                  * needed block is; else I'm passive; not ACKING
 446                  */
 447                 if (Multicast) {
 448                         if (len < TftpBlkSize)  {
 449                                 TftpEndingBlock = TftpBlock;
 450                         } else if (MasterClient) {
 451                                 TftpBlock = PrevBitmapHole =
 452                                         ext2_find_next_zero_bit(
 453                                                 Bitmap,
 454                                                 (Mapsize*8),
 455                                                 PrevBitmapHole);
 456                                 if (TftpBlock > ((Mapsize*8) - 1)) {
 457                                         printf("tftpfile too big\n");
 458                                         /* try to double it and retry */
 459                                         Mapsize <<= 1;
 460                                         mcast_cleanup();
 461                                         NetStartAgain();
 462                                         return;
 463                                 }
 464                                 TftpLastBlock = TftpBlock;
 465                         }
 466                 }
 467 #endif
 468                 TftpSend();
 469
 470 #ifdef CONFIG_MCAST_TFTP
 471                 if (Multicast) {
 472                         if (MasterClient && (TftpBlock >= TftpEndingBlock)) {
 473                                 puts("\nMulticast tftp done\n");
 474                                 mcast_cleanup();
 475                                 NetState = NETLOOP_SUCCESS;
 476                         }
 477                 }
 478                 else
 479 #endif
 480                 if (len < TftpBlkSize) {
 481                         /*
 482                          *      We received the whole thing.  Try to
 483                          *      run it.
 484                          */
 485 #ifdef CONFIG_TFTP_TSIZE
 486                         /* Print hash marks for the last packet received */
 487                         while (TftpTsize && TftpNumchars < 49) {
 488                                 putc('#');
 489                                 TftpNumchars++;
 490                         }
 491 #endif
 492                         puts("\ndone\n");
 493                         NetState = NETLOOP_SUCCESS;
 494                 }
 495                 break;
 496
 497         case TFTP_ERROR:
 498                 printf("\nTFTP error: '%s' (%d)\n",
 499                        pkt + 2, ntohs(*(ushort *)pkt));
 500
 501                 switch (ntohs(*(ushort *)pkt)) {
 502                 case TFTP_ERR_FILE_NOT_FOUND:
 503                 case TFTP_ERR_ACCESS_DENIED:
 504                         puts("Not retrying...\n");
 505                         eth_halt();
 506                         NetState = NETLOOP_FAIL;
 507                         break;
 508                 case TFTP_ERR_UNDEFINED:
 509                 case TFTP_ERR_DISK_FULL:
 510                 case TFTP_ERR_UNEXPECTED_OPCODE:
 511                 case TFTP_ERR_UNKNOWN_TRANSFER_ID:
 512                 case TFTP_ERR_FILE_ALREADY_EXISTS:
 513                 default:
 514                         puts("Starting again\n\n");
 515 #ifdef CONFIG_MCAST_TFTP
 516                         mcast_cleanup();
 517 #endif
 518                         NetStartAgain();
 519                         break;
 520                 }
 521                 break;
 522         }
 523 }
 524
 525
 526 static void
 527 TftpTimeout(void)
 528 {
 529         if (++TftpTimeoutCount > TftpTimeoutCountMax) {
 530                 puts("\nRetry count exceeded; starting again\n");
 531 #ifdef CONFIG_MCAST_TFTP
 532                 mcast_cleanup();
 533 #endif
 534                 NetStartAgain();
 535         } else {
 536                 puts("T ");
 537                 NetSetTimeout(TftpTimeoutMSecs, TftpTimeout);
 538                 TftpSend();
 539         }
 540 }
 541
 542
 543 void
 544 TftpStart(void)
 545 {
 546         char *ep;             /* Environment pointer */
 547
 548         /*
 549          * Allow the user to choose TFTP blocksize and timeout.
 550          * TFTP protocol has a minimal timeout of 1 second.
 551          */
 552         ep = getenv("tftpblocksize");
 553         if (ep != NULL)
 554                 TftpBlkSizeOption = simple_strtol(ep, NULL, 10);
 555
 556         ep = getenv("tftptimeout");
 557         if (ep != NULL)
 558                 TftpTimeoutMSecs = simple_strtol(ep, NULL, 10);
 559
 560         if (TftpTimeoutMSecs < 1000) {
 561                 printf("TFTP timeout (%ld ms) too low, "
 562                         "set minimum = 1000 ms\n",
 563                         TftpTimeoutMSecs);
 564                 TftpTimeoutMSecs = 1000;
 565         }
 566
 567         debug("TFTP blocksize = %i, timeout = %ld ms\n",
 568                 TftpBlkSizeOption, TftpTimeoutMSecs);
 569
 570         TftpServerIP = NetServerIP;
 571         if (BootFile[0] == '\0') {
 572                 sprintf(default_filename, "%02lX%02lX%02lX%02lX.img",
 573                         NetOurIP & 0xFF,
 574                         (NetOurIP >>  8) & 0xFF,
 575                         (NetOurIP >> 16) & 0xFF,
 576                         (NetOurIP >> 24) & 0xFF);
 577
 578                 strncpy(tftp_filename, default_filename, MAX_LEN);
 579                 tftp_filename[MAX_LEN-1] = 0;
 580
 581                 printf("*** Warning: no boot file name; using '%s'\n",
 582                         tftp_filename);
 583         } else {
 584                 char *p = strchr(BootFile, ':');
 585
 586                 if (p == NULL) {
 587                         strncpy(tftp_filename, BootFile, MAX_LEN);
 588                         tftp_filename[MAX_LEN-1] = 0;
 589                 } else {
 590                         TftpServerIP = string_to_ip(BootFile);
 591                         strncpy(tftp_filename, p + 1, MAX_LEN);
 592                         tftp_filename[MAX_LEN-1] = 0;
 593                 }
 594         }
 595
 596 #if defined(CONFIG_NET_MULTI)
 597         printf("Using %s device\n", eth_get_name());
 598 #endif
 599         printf("TFTP from server %pI4"
 600                 "; our IP address is %pI4", &TftpServerIP, &NetOurIP);
 601
 602         /* Check if we need to send across this subnet */
 603         if (NetOurGatewayIP && NetOurSubnetMask) {
 604             IPaddr_t OurNet     = NetOurIP    & NetOurSubnetMask;
 605             IPaddr_t ServerNet  = TftpServerIP & NetOurSubnetMask;
 606
 607             if (OurNet != ServerNet)
 608                 printf("; sending through gateway %pI4", &NetOurGatewayIP);
 609         }
 610         putc('\n');
 611
 612         printf("Filename '%s'.", tftp_filename);
 613
 614         if (NetBootFileSize) {
 615                 printf(" Size is 0x%x Bytes = ", NetBootFileSize<<9);
 616                 print_size(NetBootFileSize<<9, "");
 617         }
 618
 619         putc('\n');
 620
 621         printf("Load address: 0x%lx\n", load_addr);
 622
 623         puts("Loading: *\b");
 624
 625         TftpTimeoutCountMax = TftpRRQTimeoutCountMax;
 626
 627         NetSetTimeout(TftpTimeoutMSecs, TftpTimeout);
 628         NetSetHandler(TftpHandler);
 629
 630         TftpServerPort = WELL_KNOWN_PORT;
 631         TftpTimeoutCount = 0;
 632         TftpState = STATE_RRQ;
 633         /* Use a pseudo-random port unless a specific port is set */
 634         TftpOurPort = 1024 + (get_timer(0) % 3072);
 635
 636 #ifdef CONFIG_TFTP_PORT
 637         ep = getenv("tftpdstp");
 638         if (ep != NULL)
 639                 TftpServerPort = simple_strtol(ep, NULL, 10);
 640         ep = getenv("tftpsrcp");
 641         if (ep != NULL)
 642                 TftpOurPort = simple_strtol(ep, NULL, 10);
 643 #endif
 644         TftpBlock = 0;
 645
 646         /* zero out server ether in case the server ip has changed */
 647         memset(NetServerEther, 0, 6);
 648         /* Revert TftpBlkSize to dflt */
 649         TftpBlkSize = TFTP_BLOCK_SIZE;
 650 #ifdef CONFIG_MCAST_TFTP
 651         mcast_cleanup();
 652 #endif
 653 #ifdef CONFIG_TFTP_TSIZE
 654         TftpTsize = 0;
 655         TftpNumchars = 0;
 656 #endif
 657
 658         TftpSend();
 659 }
 660
 661 #ifdef CONFIG_MCAST_TFTP
 662 /* Credits: atftp project.
 663  */
 664
 665 /* pick up BcastAddr, Port, and whether I am [now] the master-client. *
 666  * Frame:
 667  *    +-------+-----------+---+-------~~-------+---+
 668  *    |  opc  | multicast | 0 | addr, port, mc | 0 |
 669  *    +-------+-----------+---+-------~~-------+---+
 670  * The multicast addr/port becomes what I listen to, and if 'mc' is '1' then
 671  * I am the new master-client so must send ACKs to DataBlocks.  If I am not
 672  * master-client, I'm a passive client, gathering what DataBlocks I may and
 673  * making note of which ones I got in my bitmask.
 674  * In theory, I never go from master->passive..
 675  * .. this comes in with pkt already pointing just past opc
 676  */
 677 static void parse_multicast_oack(char *pkt, int len)
 678 {
 679         int i;
 680         IPaddr_t addr;
 681         char *mc_adr, *port,  *mc;
 682
 683         mc_adr = port = mc = NULL;
 684         /* march along looking for 'multicast\0', which has to start at least
 685          * 14 bytes back from the end.
 686          */
 687         for (i = 0; i < len-14; i++)
 688                 if (strcmp(pkt+i, "multicast") == 0)
 689                         break;
 690         if (i >= (len-14)) /* non-Multicast OACK, ign. */
 691                 return;
 692
 693         i += 10; /* strlen multicast */
 694         mc_adr = pkt+i;
 695         for (; i < len; i++) {
 696                 if (*(pkt+i) == ',') {
 697                         *(pkt+i) = '\0';
 698                         if (port) {
 699                                 mc = pkt+i+1;
 700                                 break;
 701                         } else {
 702                                 port = pkt+i+1;
 703                         }
 704                 }
 705         }
 706         if (!port || !mc_adr || !mc) return;
 707         if (Multicast && MasterClient) {
 708                 printf("I got a OACK as master Client, WRONG!\n");
 709                 return;
 710         }
 711         /* ..I now accept packets destined for this MCAST addr, port */
 712         if (!Multicast) {
 713                 if (Bitmap) {
 714                         printf("Internal failure! no mcast.\n");
 715                         free(Bitmap);
 716                         Bitmap = NULL;
 717                         ProhibitMcast = 1;
 718                         return ;
 719                 }
 720                 /* I malloc instead of pre-declare; so that if the file ends
 721                  * up being too big for this bitmap I can retry
 722                  */
 723                 Bitmap = malloc(Mapsize);
 724                 if (!Bitmap) {
 725                         printf("No Bitmap, no multicast. Sorry.\n");
 726                         ProhibitMcast = 1;
 727                         return;
 728                 }
 729                 memset(Bitmap, 0, Mapsize);
 730                 PrevBitmapHole = 0;
 731                 Multicast = 1;
 732         }
 733         addr = string_to_ip(mc_adr);
 734         if (Mcast_addr != addr) {
 735                 if (Mcast_addr)
 736                         eth_mcast_join(Mcast_addr, 0);
 737                 Mcast_addr = addr;
 738                 if (eth_mcast_join(Mcast_addr, 1)) {
 739                         printf("Fail to set mcast, revert to TFTP\n");
 740                         ProhibitMcast = 1;
 741                         mcast_cleanup();
 742                         NetStartAgain();
 743                 }
 744         }
 745         MasterClient = (unsigned char)simple_strtoul((char *)mc, NULL, 10);
 746         Mcast_port = (unsigned short)simple_strtoul(port, NULL, 10);
 747         printf("Multicast: %s:%d [%d]\n", mc_adr, Mcast_port, MasterClient);
 748         return;
 749 }
 750
 751 #endif /* Multicast TFTP */