Patch from John Powers, adds multicast (rfc2090) and timeout (rfc2349)
authorGlenn L McGrath <bug1@ihug.co.nz>
Fri, 5 Mar 2004 15:52:57 +0000 (15:52 -0000)
committerGlenn L McGrath <bug1@ihug.co.nz>
Fri, 5 Mar 2004 15:52:57 +0000 (15:52 -0000)
options

patches/tftp_timeout_multicast.diff [new file with mode: 0644]

diff --git a/patches/tftp_timeout_multicast.diff b/patches/tftp_timeout_multicast.diff
new file mode 100644 (file)
index 0000000..a76a18c
--- /dev/null
@@ -0,0 +1,1053 @@
+Index: AUTHORS
+===================================================================
+RCS file: /var/cvs/busybox/AUTHORS,v
+retrieving revision 1.40
+diff -u -r1.40 AUTHORS
+--- a/AUTHORS  9 Oct 2003 21:19:21 -0000       1.40
++++ b/AUTHORS  5 Mar 2004 15:45:47 -0000
+@@ -92,6 +92,9 @@
+     Original author of BusyBox in 1995, 1996. Some of his code can 
+     still be found hiding here and there...
++John Powers <jpp@ti.com>
++    Added multicast option (rfc2090) and timeout option (rfc2349) to tftp.
++
+ Tim Riker <Tim@Rikers.org>
+     bug fixes, member of fan club
+Index: include/usage.h
+===================================================================
+RCS file: /var/cvs/busybox/include/usage.h,v
+retrieving revision 1.191
+diff -u -r1.191 usage.h
+--- a/include/usage.h  25 Feb 2004 10:35:55 -0000      1.191
++++ b/include/usage.h  5 Mar 2004 15:45:59 -0000
+@@ -2492,6 +2492,21 @@
+ #else
+   #define USAGE_TFTP_BS(a)
+ #endif
++#ifdef CONFIG_FEATURE_TFTP_TIMEOUT
++  #define USAGE_TFTP_TIMEOUT(a) a
++#else
++  #define USAGE_TFTP_TIMEOUT(a)
++#endif
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++  #define USAGE_TFTP_MULTICAST(a) a
++#else
++  #define USAGE_TFTP_MULTICAST(a)
++#endif
++#ifdef CONFIG_FEATURE_TFTP_DEBUG
++  #define USAGE_TFTP_DEBUG(a) a
++#else
++  #define USAGE_TFTP_DEBUG(a)
++#endif
+ #define tftp_trivial_usage \
+       "[OPTION]... HOST [PORT]"
+@@ -2508,6 +2523,16 @@
+       ) \
+       USAGE_TFTP_BS( \
+       "\t-b SIZE\tTransfer blocks of SIZE octets.\n" \
++      ) \
++      USAGE_TFTP_TIMEOUT( \
++      "\t-T SEC\tClient timeout SEC seconds (default: 5).\n" \
++      "\t-t SEC\tServer timeout SEC seconds\n" \
++      ) \
++      USAGE_TFTP_MULTICAST( \
++      "\t-m\tMulticast get file.\n" \
++      ) \
++      USAGE_TFTP_DEBUG( \
++      "\t-D\tPrint debug messages.\n" \
+       )
+ #define time_trivial_usage \
+       "[OPTION]... COMMAND [ARGS...]"
+Index: networking/Config.in
+===================================================================
+RCS file: /var/cvs/busybox/networking/Config.in,v
+retrieving revision 1.27
+diff -u -r1.27 Config.in
+--- a/networking/Config.in     22 Feb 2004 12:25:47 -0000      1.27
++++ b/networking/Config.in     5 Mar 2004 15:45:59 -0000
+@@ -522,6 +522,13 @@
+         Add support for the GET command within the TFTP client.  This allows
+         a client to retrieve a file from a TFTP server.
++config CONFIG_FEATURE_TFTP_MULTICAST
++      bool "  Enable \"multicast\" option"
++      default n
++      depends on CONFIG_FEATURE_TFTP_GET
++      help
++        Allow the client to receive multicast file transfers.
++
+ config CONFIG_FEATURE_TFTP_PUT
+       bool "  Enable \"put\" command"
+       default y
+@@ -531,12 +538,19 @@
+         a client to transfer a file to a TFTP server.
+ config CONFIG_FEATURE_TFTP_BLOCKSIZE
+-      bool "  Enable \"blocksize\" command"
++      bool "  Enable \"blksize\" option"
+       default n
+       depends on CONFIG_TFTP
+       help
+         Allow the client to specify the desired block size for transfers.
++config CONFIG_FEATURE_TFTP_TIMEOUT
++      bool "  Enable \"timeout\" option"
++      default n
++      depends on CONFIG_TFTP
++      help
++        Allow the client to negotiate timeout option with server.
++
+ config CONFIG_FEATURE_TFTP_DEBUG
+       bool "  Enable debug"
+       default n
+Index: networking/tftp.c
+===================================================================
+RCS file: /var/cvs/busybox/networking/tftp.c,v
+retrieving revision 1.25
+diff -u -r1.25 tftp.c
+--- a/networking/tftp.c        5 Mar 2004 13:04:39 -0000       1.25
++++ b/networking/tftp.c        5 Mar 2004 15:46:00 -0000
+@@ -1,11 +1,26 @@
++/* vi: set sw=4 ts=4: */
+ /* ------------------------------------------------------------------------- */
+ /* tftp.c                                                                    */
++/* Copyright (c) 2003, 2004 Texas Instruments                                */
++/*                                                                           */
++/* This package is free software;  you can redistribute it and/or            */
++/* modify it under the terms of the license found in the file                */
++/* named COPYING that should have accompanied this file.                     */
++/*                                                                           */
++/* THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR             */
++/* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED            */
++/* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.       */
+ /*                                                                           */
+ /* A simple tftp client for busybox.                                         */
+ /* Tries to follow RFC1350.                                                  */
+ /* Only "octet" mode supported.                                              */
+ /* Optional blocksize negotiation (RFC2347 + RFC2348)                        */
+ /*                                                                           */
++/* New features added at Texas Instruments, October 2003                     */
++/* Author: John Powers                                                       */
++/* Multicast option: rfc2090                                                 */
++/* Timeout option: rfc2349                                                   */
++/*                                                                           */
+ /* Copyright (C) 2001 Magnus Damm <damm@opensource.se>                       */
+ /*                                                                           */
+ /* Parts of the code based on:                                               */
+@@ -46,8 +61,20 @@
+ #include "busybox.h"
++#if defined(CONFIG_FEATURE_TFTP_BLOCKSIZE) || defined(CONFIG_FEATURE_TFTP_MULTICAST) || defined(CONFIG_FEATURE_TFTP_TIMEOUT)
++  #define TFTP_OPTIONS
++#endif
++
+ //#define CONFIG_FEATURE_TFTP_DEBUG
++#ifdef CONFIG_FEATURE_TFTP_DEBUG
++      static void printtime(void);
++      #define dprintf(fmt...) if (debug) {printtime(); printf(fmt);}
++      int debug = 0;
++#else
++      #define dprintf(fmt...)
++#endif
++
+ #define TFTP_BLOCKSIZE_DEFAULT 512 /* according to RFC 1350, don't change */
+ #define TFTP_TIMEOUT 5             /* seconds */
+@@ -68,12 +95,24 @@
+       "Illegal TFTP operation",
+       "Unknown transfer ID",
+       "File already exists",
+-      "No such user"
++      "No such user",
++#ifdef TFTP_OPTIONS
++      "Unsupported option",
++#endif
+ };
+ const int tftp_cmd_get = 1;
+ const int tftp_cmd_put = 2;
++
++struct tftp_option {
++      int multicast;
++      int blksize;
++      int client_timeout;
++      int server_timeout;
++};
++
++
+ #ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
+ static int tftp_blocksize_check(int blocksize, int bufsize)  
+@@ -93,16 +132,158 @@
+       return blocksize;
+ }
++#endif
++
++#ifdef CONFIG_FEATURE_TFTP_TIMEOUT
++
++static int
++tftp_timeout_check(int timeout)
++{
++      /* Check if timeout seconds is valid:
++       * RFC2349 says between 1 and 255.
++       */
++
++      if (timeout < 1 || timeout > 255) {
++              bb_error_msg("bad timeout value");
++              return 0;
++      }
++      return timeout;
++}
++
++#endif
++
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++static int
++tftp_multicast_check(const char *opt, char **phost, unsigned short *pport, int *pactive)
++{
++      /* Option string contains comma delimited addr,port,active.
++       * addr = multicast IP address
++       * port = port number
++       * active = 1 if active client
++       *          0 if passive client
++       *
++       * Addr and port will be empty fields when the server notifies a
++       * passive client that it is now the active client.
++       *
++       * The host address string must be freed by the caller. Neither host
++       * nor port will be set/changed if the input fields are empty.
++       *
++       * If any tokenization errors occur in the opt string, the host
++       * address string is automatically freed.
++       *
++       * Return 0 if any tokenization error, 1 if all parameters are good.
++       */
++
++      char *token = NULL;
++      char *parse_buf = NULL;
++      char *tokenv = NULL;
++      char *host = NULL;
++      int port;
++      int active;
++
++      parse_buf = bb_xstrdup(opt);
++
++      dprintf("multicast option=%s\n", opt);
++
++      /* IP address */
++      if ((token = strtok_r(parse_buf, ",", &tokenv)) == NULL) {
++              dprintf("tftp_multicast_check: cannot parse IP address from %s\n", parse_buf);
++              free(parse_buf);
++              return 0;
++      }
++      if (strlen(token) > 0)
++              *phost = host = bb_xstrdup(token);
++
++      /* Port */
++      if ((token = strtok_r(NULL, ",", &tokenv)) == NULL) {
++              dprintf("tftp_multicast_check: cannot parse port number from %s\n", tokenv);
++              goto token_error;
++      }
++      if (strlen(token) > 0) {
++              port = atoi(token);
++              if (port < 0 || port > 0xFFFF) {
++                      dprintf("tftp_multicast_check: bad port number (%d)\n", port);
++                      goto token_error;
++              }
++              *pport = htons(port);
++      }
++
++      /* Active/passive */
++      if ((token = strtok_r(NULL, ",", &tokenv)) == NULL) {
++              dprintf("tftp_multicast_check: cannot parse active/passive from %s\n", tokenv);
++              goto token_error;
++      }
++      active = atoi(token);
++      if (active != 0 && active != 1) {
++              dprintf("tftp_multicast_check: bad active/passive flag (%d)\n", active);
++              goto token_error;
++      }
++      *pactive = active;
++
++      free(parse_buf);
++      return 1;
++
++token_error:
++      free(parse_buf);
++      if (host != NULL)
++              free(host);
++      *phost = NULL;
++      return 0;
++
++}
++
++#define VECTOR_QUANTUM_WIDTH 8
++#define VECTOR_QUANTUM_ALL_ONES ((1<<VECTOR_QUANTUM_WIDTH)-1)
++
++static void inline
++bit_set(int bit, unsigned char *vector)
++{
++      int offset = bit / VECTOR_QUANTUM_WIDTH;
++      int mask = 1 << (bit % VECTOR_QUANTUM_WIDTH);
++      vector[offset] |= mask;
++}
++
++static int inline
++bit_isset(int bit, const unsigned char *vector)
++{
++      int offset = bit / VECTOR_QUANTUM_WIDTH;
++      int mask = 1 << (bit % VECTOR_QUANTUM_WIDTH);
++      return vector[offset] & mask ? 1 : 0;
++}
++
++static int inline
++bit_lmz(const unsigned char *vector)
++{
++      /* Return number of left-most zero in bit vector */
++      const unsigned char *vp = vector;
++      int i;
++      unsigned char velem;
++
++      while (*vp == VECTOR_QUANTUM_ALL_ONES)
++              vp++;
++      velem = *vp;
++      for (i = 0; i < VECTOR_QUANTUM_WIDTH; i++) {
++              if ((velem & (1 << i)) == 0)
++                      break;
++      }
++      dprintf("bit_lmz: block=%d\n", (vp - vector)*VECTOR_QUANTUM_WIDTH + i);
++      return (vp - vector)*VECTOR_QUANTUM_WIDTH + i;
++}
++
++#endif
++
++
++
++#ifdef TFTP_OPTIONS
++
+ static char *tftp_option_get(char *buf, int len, char *option)  
+ {
+-        int opt_val = 0;
++      int opt_val = 0;
+       int opt_found = 0;
+       int k;
+-  
+-      while (len > 0) {
++      while (len > 0) {
+               /* Make sure the options are terminated correctly */
+-
+               for (k = 0; k < len; k++) {
+                       if (buf[k] == '\0') {
+                               break;
+@@ -117,9 +298,8 @@
+                       if (strcasecmp(buf, option) == 0) {
+                               opt_found = 1;
+                       }
+-              }      
+-              else {
+-                      if (opt_found) {
++              } else {
++                      if (opt_found) {
+                               return buf;
+                       }
+               }
+@@ -138,7 +318,8 @@
+ #endif
+ static inline int tftp(const int cmd, const struct hostent *host,
+-      const char *remotefile, int localfd, const unsigned short port, int tftp_bufsize)
++      const char *remotefile, int localfd, const unsigned short port,
++      struct tftp_option *option)
+ {
+       const int cmd_get = cmd & tftp_cmd_get;
+       const int cmd_put = cmd & tftp_cmd_put;
+@@ -155,18 +336,29 @@
+       int len;
+       int opcode = 0;
+       int finished = 0;
+-      int timeout = bb_tftp_num_retries;
++      int retry = bb_tftp_num_retries;
+       unsigned short block_nr = 1;
+-#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
+-      int want_option_ack = 0;
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++      struct hostent *mchost;
++      struct sockaddr_in mcsa;
++      char *mchostname;
++      unsigned short mcport;
++      unsigned char *mcblockmap = NULL;
++      int master_client = 1;
++      int mcfd = -1;
++      int mcmaxblock = 0x10000;
++      int ack_oack = 0;
++#else
++      #define master_client 1
++    #define ack_oack 0
+ #endif
+       /* Can't use RESERVE_CONFIG_BUFFER here since the allocation
+        * size varies meaning BUFFERS_GO_ON_STACK would fail */
+-      char *buf=xmalloc(tftp_bufsize + 4);
++      char *buf=xmalloc(option->blksize + 4);
+-      tftp_bufsize += 4;
++      int tftp_bufsize = option->blksize + 4;
+       if ((socketfd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
+               bb_perror_msg("socket");
+@@ -183,15 +375,21 @@
+       memcpy(&sa.sin_addr, (struct in_addr *) host->h_addr,
+                  sizeof(sa.sin_addr));
+-      /* build opcode */
+-
+-      if (cmd_get) {
+-              opcode = TFTP_RRQ;
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++      if (option->multicast) {
++              const int bmsize = 0x10000 / VECTOR_QUANTUM_WIDTH;
++              if ((mcfd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
++                      bb_perror_msg("multicast socket");
++                      return EXIT_FAILURE;
++              }
++              mcblockmap = xmalloc(bmsize+1);
++              memset(mcblockmap, 0, bmsize+1);
+       }
++#endif
+-      if (cmd_put) {
+-              opcode = TFTP_WRQ;
+-      }
++      /* build opcode */
++
++      opcode = cmd_get ? TFTP_RRQ : TFTP_WRQ;
+       while (1) {
+@@ -203,7 +401,7 @@
+               cp += 2;
+-              /* add filename and mode */
++              /* First packet of file transfer includes file name, mode, and options */
+               if ((cmd_get && (opcode == TFTP_RRQ)) ||
+                       (cmd_put && (opcode == TFTP_WRQ))) {
+@@ -223,7 +421,7 @@
+                       }
+                       if (too_long || ((&buf[tftp_bufsize - 1] - cp) < 6)) {
+-                              bb_error_msg("too long remote-filename");
++                              bb_error_msg("too long: remote filename");
+                               break;
+                       }
+@@ -238,8 +436,8 @@
+                       if (len != TFTP_BLOCKSIZE_DEFAULT) {
+-                              if ((&buf[tftp_bufsize - 1] - cp) < 15) {
+-                                      bb_error_msg("too long remote-filename");
++                              if ((&buf[tftp_bufsize - 1] - cp) < 15) {
++                                      bb_error_msg("buffer too small for blksize option");
+                                       break;
+                               }
+@@ -249,16 +447,65 @@
+                               cp += 8;
+                               cp += snprintf(cp, 6, "%d", len) + 1;
++                      }
++#endif
++
++
++
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++
++                      if (option->multicast) {
++                              if ((&buf[tftp_bufsize - 1] - cp) < 12) {
++                                      bb_error_msg("buffer too small for multicast option");
++                                      break;
++                              }
++
++                              /* add "multicast" option */
+-                              want_option_ack = 1;
++                              memcpy(cp, "multicast\0", 11);
++                              cp += 11;
++
++                              option->multicast = 0;  /* turn back on when server accepts option */
++                              ack_oack = 1;   /* acknowledge OACK */
+                       }
++
+ #endif
++
++#ifdef CONFIG_FEATURE_TFTP_TIMEOUT
++
++                      if (option->server_timeout != TFTP_TIMEOUT) {
++                              if ((&buf[tftp_bufsize - 1] - cp) < 12) {
++                                      bb_error_msg("buffer too small for timeout option");
++                                      break;
++                              }
++
++                              /* add "timeout" option */
++
++                              memcpy(cp, "timeout", 8);
++                              cp += 8;
++
++                              cp += snprintf(cp, 4, "%d", option->server_timeout) + 1;
++                      }
++#endif
++
+               }
+               /* add ack and data */
+-              if ((cmd_get && (opcode == TFTP_ACK)) ||
+-                      (cmd_put && (opcode == TFTP_DATA))) {
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++              else if (option->multicast && opcode == TFTP_ACK) {
++                      if (master_client || ack_oack) {
++                              int blocknum = bit_lmz(mcblockmap);
++                              *((unsigned short *) cp) = htons(blocknum);
++                              cp += 2;
++                              if (blocknum >= mcmaxblock)
++                                      finished = 1;
++                              dprintf("ack block %d/%d %s\n", blocknum, mcmaxblock, finished? "finished": "");
++                      }
++              }
++#endif
++              else if ((cmd_get && opcode == TFTP_ACK) ||
++                      (cmd_put && opcode == TFTP_DATA)) {
+                       *((unsigned short *) cp) = htons(block_nr);
+@@ -275,7 +522,7 @@
+                               }
+                               if (len != (tftp_bufsize - 4)) {
+-                                      finished++;
++                                      finished = 1;
+                               }
+                               cp += len;
+@@ -283,82 +530,119 @@
+               }
+-              /* send packet */
++              /* send packet and receive reply */
+-              timeout = bb_tftp_num_retries;  /* re-initialize */
++              retry = bb_tftp_num_retries;  /* re-initialize */
+               do {
+-
++                      int selectrc;
+                       len = cp - buf;
+-#ifdef CONFIG_FEATURE_TFTP_DEBUG
+-                      fprintf(stderr, "sending %u bytes\n", len);
+-                      for (cp = buf; cp < &buf[len]; cp++)
+-                              fprintf(stderr, "%02x ", (unsigned char)*cp);
+-                      fprintf(stderr, "\n");
+-#endif
+-                      if (sendto(socketfd, buf, len, 0,
+-                                      (struct sockaddr *) &sa, sizeof(sa)) < 0) {
+-                              bb_perror_msg("send");
+-                              len = -1;
+-                              break;
+-                      }
+-
++                      /* send packet */
++                      if ((len > 2) && (! option->multicast || master_client || ack_oack)) {
+-                      if (finished && (opcode == TFTP_ACK)) {
+-                              break;
++#ifdef CONFIG_FEATURE_TFTP_DEBUG
++                              dprintf("sending %u bytes\n", len);
++                              for (cp = buf; cp < &buf[len]; cp++)
++                                      if (debug)
++                                              printf("%02x ", *(unsigned char *)cp);
++                              if (debug)
++                                      printf("\n");
++#endif
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++                              ack_oack = 0;
++#endif
++                              if (sendto(socketfd, buf, len, 0, (struct sockaddr *) &sa, sizeof(sa)) < 0) {
++                                      bb_perror_msg("send");
++                                      len = -1;
++                                      break;
++                              }
++                              if (finished && opcode == TFTP_ACK) {
++                                      break;
++                              }
+                       }
+-                      /* receive packet */
++                      /* receive reply packet */
+                       memset(&from, 0, sizeof(from));
+                       fromlen = sizeof(from);
+-                      tv.tv_sec = TFTP_TIMEOUT;
++                      tv.tv_sec = option->client_timeout;
+                       tv.tv_usec = 0;
+                       FD_ZERO(&rfds);
+                       FD_SET(socketfd, &rfds);
++                      dprintf("set to receive from socketfd (%d)\n", socketfd);
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++                      if (option->multicast) {
++                              FD_SET(mcfd, &rfds);
++                              dprintf("set to receive from mcfd (%d)\n", mcfd);
++                      }
++#endif
+-                      switch (select(FD_SETSIZE, &rfds, NULL, NULL, &tv)) {
+-                      case 1:
+-                              len = recvfrom(socketfd, buf, tftp_bufsize, 0,
+-                                              (struct sockaddr *) &from, &fromlen);
+-
+-                              if (len < 0) {
+-                                      bb_perror_msg("recvfrom");
+-                                      break;
++                      dprintf("select\n");
++                      selectrc = select(FD_SETSIZE, &rfds, NULL, NULL, &tv);
++                      if (selectrc > 0) {
++                              /* A packet was received */
++                              if (FD_ISSET(socketfd, &rfds)) { /* Unicast packet */
++                                      dprintf("from socketfd\n");
++                                      len = recvfrom(socketfd, buf, tftp_bufsize, 0, (struct sockaddr *) &from, &fromlen);
++
++                                      if (len < 0) {
++                                              bb_perror_msg("recvfrom");
++                                      } else {
++                                              if (sa.sin_port == port) {
++                                                      sa.sin_port = from.sin_port;
++                                              }
++                                              if (sa.sin_port == from.sin_port) {
++                                                      retry = 0;
++                                              } else {
++                                                      /* bad packet */
++                                                      /* discard the packet - treat as timeout */
++                                                      retry = bb_tftp_num_retries;
++                                                      bb_error_msg("timeout");
++                                              }
++                                      }
+                               }
+-                              timeout = 0;
+-
+-                              if (sa.sin_port == port) {
+-                                      sa.sin_port = from.sin_port;
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++                              else if (option->multicast && FD_ISSET(mcfd, &rfds)) { /* Multicast packet */
++                                      dprintf("from mcfd\n");
++                                      len = recvfrom(mcfd, buf, tftp_bufsize, 0, (struct sockaddr *) &from, &fromlen);
++                                      if (len < 0) {
++                                              bb_perror_msg("multicast recvfrom");
++                                      } else {
++                                              if (mcsa.sin_port == mcport) {
++                                                      mcsa.sin_port = from.sin_port;
++                                              }
++                                              if (mcsa.sin_port == from.sin_port) {
++                                                      retry = 0;
++                                              } else {
++                                                      retry = bb_tftp_num_retries;
++                                                      bb_error_msg("multicast timeout");
++                                              }
++                                      }
+                               }
+-                              if (sa.sin_port == from.sin_port) {
+-                                      break;
+-                              }
+-
+-                              /* fall-through for bad packets! */
+-                              /* discard the packet - treat as timeout */
+-                              timeout = bb_tftp_num_retries;
++#endif
+-                      case 0:
++                      } else if (selectrc == 0) {
++                              /* Time out */
++                              dprintf("timeout\n");
+                               bb_error_msg("timeout");
+-                              timeout--;
+-                              if (timeout == 0) {
++                              retry--;
++                              if (retry == 0) {
+                                       len = -1;
+                                       bb_error_msg("last timeout");
+                               }
+-                              break;
+-
+-                      default:
++                      } else {
++                              /* Error condition */
++                              dprintf("error\n");
+                               bb_perror_msg("select");
+                               len = -1;
+                       }
+-              } while (timeout && (len >= 0));
++              } while (retry && len >= 0);
+               if ((finished) || (len < 0)) {
+                       break;
+@@ -370,9 +654,8 @@
+               opcode = ntohs(*((unsigned short *) buf));
+               tmp = ntohs(*((unsigned short *) &buf[2]));
+-#ifdef CONFIG_FEATURE_TFTP_DEBUG
+-              fprintf(stderr, "received %d bytes: %04x %04x\n", len, opcode, tmp);
+-#endif
++              dprintf("received %d bytes: %04x %04x\n", len, opcode, tmp);
++              dprintf("master_client=%d\n", master_client);
+               if (opcode == TFTP_ERROR) {
+                       char *msg = NULL;
+@@ -393,55 +676,116 @@
+                       break;
+               }
+-#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
+-              if (want_option_ack) {
++#ifdef TFTP_OPTIONS
+-                       want_option_ack = 0;
++              if (opcode == TFTP_OACK) {
+-                       if (opcode == TFTP_OACK) {
++                      /* server seems to support options */
+-                               /* server seems to support options */
++                      char *res;
++                      
++                      block_nr = 0;           /* acknowledge option packet with block number 0 */
++                      opcode = cmd_put ? TFTP_DATA : TFTP_ACK;
+-                               char *res;
+-                               res = tftp_option_get(&buf[2], len-2, 
+-                                                     "blksize");
++#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
++                      res = tftp_option_get(&buf[2], len-2, "blksize");
+-                               if (res) {
+-                                       int blksize = atoi(res);
+-                           
+-                                       if (tftp_blocksize_check(blksize,
+-                                                         tftp_bufsize - 4)) {
++                      if (res) {
++                              int blksize = atoi(res);
+-                                               if (cmd_put) {
+-                                                       opcode = TFTP_DATA;
+-                                               }
+-                                               else {
+-                                                       opcode = TFTP_ACK;
+-                                               }
+-#ifdef CONFIG_FEATURE_TFTP_DEBUG
+-                                               fprintf(stderr, "using blksize %u\n", blksize);
++                              if (tftp_blocksize_check(blksize, tftp_bufsize - 4)) {
++                                      dprintf("using blksize %d\n", blksize);
++                                      tftp_bufsize = blksize + 4;
++                                      free(buf);
++                                      buf = xmalloc(tftp_bufsize);
++                              } else {
++                                      bb_error_msg("bad blksize %d", blksize);
++                                      break;
++                              }
++                      }
+ #endif
+-                                               tftp_bufsize = blksize + 4;
+-                                               block_nr = 0;
+-                                               continue;
+-                                       }
+-                               }
+-                               /* FIXME:
+-                                * we should send ERROR 8 */
+-                               bb_error_msg("bad server option");
+-                               break;
+-                       }
+-                       bb_error_msg("warning: blksize not supported by server"
+-                                 " - reverting to 512");
+-                       tftp_bufsize = TFTP_BLOCKSIZE_DEFAULT + 4;
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++                      res = tftp_option_get(&buf[2], len-2, "multicast");
++
++                      if (res) {
++                              ack_oack = 1;
++                              if (tftp_multicast_check(res, &mchostname, &mcport, &master_client)) {
++                                      struct ip_mreq mreq;
++                                      struct in_addr mcaddr;
++
++                                      dprintf("using multicast\n");
++
++                                      mchost = xgethostbyname(mchostname);
++                                      if (mchost) {
++                                              memcpy(&mcaddr, mchost->h_addr, mchost->h_length);
++                                              if (! IN_MULTICAST(ntohl(mcaddr.s_addr))) {
++                                                      bb_error_msg("bad multicast address: %s", mchostname);
++                                                      break;
++                                              }
++                                      } else {
++                                              bb_error_msg("bad multicast address: %s", mchostname);
++                                              break;
++                                      }
++
++                                      memset(&mcsa, 0, sizeof(mcsa));
++                                      mcsa.sin_family = AF_INET;
++                                      mcsa.sin_addr.s_addr = htonl(INADDR_ANY);
++                                      mcsa.sin_port = mcport;
++
++                                      bind(mcfd, (struct sockaddr *)&mcsa, sizeof(mcsa));
++
++                                      mreq.imr_multiaddr.s_addr = mcaddr.s_addr;
++                                      mreq.imr_interface.s_addr = htonl(INADDR_ANY);
++
++                                      if (setsockopt(mcfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
++                                      {
++                                              bb_error_msg("setsockopt");
++                                              break;
++                                      }
++
++                                      option->multicast = 1;
++                              } else {
++                                      bb_error_msg("bad multicast option value: %s", res);
++                                      break;
++                              }
++                      }
++#endif
++
+               }
++              else
+ #endif
+               if (cmd_get && (opcode == TFTP_DATA)) {
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++                      if (option->multicast) {
++                              int bn = tmp - 1;
++                              /* Do I need this block? */
++                              if (! bit_isset(bn, mcblockmap)) {
++                                      lseek(localfd, bn*(tftp_bufsize-4), SEEK_SET);
++                                      len = write(localfd, &buf[4], len-4);
++                                      if (len < 0) {
++                                              bb_perror_msg("write");
++                                              break;
++                                      }
++                                      bit_set(bn, mcblockmap);
++                                      if (len != (tftp_bufsize-4)) {
++                                              mcmaxblock = tmp;
++                                              dprintf("mcmaxblock=%d, (len(%d) != tftp_bufsize-4(%d))\n", mcmaxblock, len, tftp_bufsize-4);
++                                      }
++                                      opcode = TFTP_ACK;
++                              }
++                              /* Do not acknowledge block if I already have a copy of the block. A situation can arise when the server
++                               * and client timeout nearly simultaneously. The server retransmits the block at the same time the client
++                               * re-requests the block. From then on out, each block is transmitted twice--not a good use of bandwidth.
++                               */
++                      }
++                      else
++#endif
++
+                       if (tmp == block_nr) {
+                           
+                               len = write(localfd, &buf[4], len - 4);
+@@ -452,15 +796,14 @@
+                               }
+                               if (len != (tftp_bufsize - 4)) {
+-                                      finished++;
++                                      finished = 1;
+                               }
+                               opcode = TFTP_ACK;
+-                              continue;
+                       }
+               }
+-              if (cmd_put && (opcode == TFTP_ACK)) {
++              else if (cmd_put && opcode == TFTP_ACK) {
+                       if (tmp == (unsigned short)(block_nr - 1)) {
+                               if (finished) {
+@@ -468,15 +811,19 @@
+                               }
+                               opcode = TFTP_DATA;
+-                              continue;
+                       }
+               }
+       }
+ #ifdef CONFIG_FEATURE_CLEAN_UP
+       close(socketfd);
++      free(buf);
++
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++      if (mcblockmap != NULL)
++              free(mcblockmap);
++#endif
+-        free(buf);
+ #endif
+       return finished ? EXIT_SUCCESS : EXIT_FAILURE;
+@@ -487,13 +834,18 @@
+       struct hostent *host = NULL;
+       char *localfile = NULL;
+       char *remotefile = NULL;
+-      int port;
++      unsigned short port;
+       int cmd = 0;
+       int fd = -1;
+       int flags = 0;
+       int opt;
+       int result;
+-      int blocksize = TFTP_BLOCKSIZE_DEFAULT;
++      struct tftp_option option = {
++              .multicast              = 0,
++              .blksize                = TFTP_BLOCKSIZE_DEFAULT,
++              .client_timeout = TFTP_TIMEOUT,
++              .server_timeout = TFTP_TIMEOUT,
++      };
+       /* figure out what to pass to getopt */
+@@ -515,13 +867,45 @@
+ #define PUT 
+ #endif
+-      while ((opt = getopt(argc, argv, BS GET PUT "l:r:")) != -1) {
++#ifdef CONFIG_FEATURE_TFTP_TIMEOUT
++#define TO "T:t:"
++#else
++#define TO
++#endif
++
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++#define MC "m"
++#else
++#define MC
++#endif
++
++#ifdef CONFIG_FEATURE_TFTP_DEBUG
++#define DB "D"
++#else
++#define DB
++#endif
++
++      while ((opt = getopt(argc, argv, BS GET PUT TO MC DB "l:r:")) != -1) {
+               switch (opt) {
+ #ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
+               case 'b':
+-                      blocksize = atoi(optarg);
+-                      if (!tftp_blocksize_check(blocksize, 0)) {
+-                                return EXIT_FAILURE;
++                      option.blksize = atoi(optarg);
++                      if (!tftp_blocksize_check(option.blksize, 0)) {
++                              return EXIT_FAILURE;
++                      }
++                      break;
++#endif
++#ifdef CONFIG_FEATURE_TFTP_TIMEOUT
++              case 'T':
++                      option.client_timeout = atoi(optarg);
++                      if (!tftp_timeout_check(option.client_timeout)) {
++                              return EXIT_FAILURE;
++                      }
++                      break;
++              case 't':
++                      option.server_timeout = atoi(optarg);
++                      if (!tftp_timeout_check(option.server_timeout)) {
++                              return EXIT_FAILURE;
+                       }
+                       break;
+ #endif
+@@ -537,18 +921,34 @@
+                       flags = O_RDONLY;
+                       break;
+ #endif
++#ifdef CONFIG_FEATURE_TFTP_MULTICAST
++              case 'm':
++                      option.multicast = 1;   /* receive multicast file */
++                      break;
++#endif
++#ifdef CONFIG_FEATURE_TFTP_DEBUG
++              case 'D':
++                      debug = 1;
++                      break;
++#endif
+               case 'l': 
+                       localfile = bb_xstrdup(optarg);
+                       break;
+               case 'r':
+                       remotefile = bb_xstrdup(optarg);
+                       break;
++              default:
++                      bb_show_usage();
+               }
+       }
+       if ((cmd == 0) || (optind == argc)) {
+               bb_show_usage();
+       }
++      if (cmd == tftp_cmd_put && option.multicast) {
++              fprintf(stderr, "Multicast (-m) invalid option with put (-p) command\n");
++              exit(EXIT_FAILURE);
++      }
+       if(localfile && strcmp(localfile, "-") == 0) {
+           fd = fileno((cmd==tftp_cmd_get)? stdout : stdin);
+       }
+@@ -566,14 +966,12 @@
+       host = xgethostbyname(argv[optind]);
+       port = bb_lookup_port(argv[optind + 1], "udp", 69);
+-#ifdef CONFIG_FEATURE_TFTP_DEBUG
+-      fprintf(stderr, "using server \"%s\", remotefile \"%s\", "
++      dprintf("using server \"%s\", remotefile \"%s\", "
+               "localfile \"%s\".\n",
+               inet_ntoa(*((struct in_addr *) host->h_addr)),
+               remotefile, localfile);
+-#endif
+-      result = tftp(cmd, host, remotefile, fd, port, blocksize);
++      result = tftp(cmd, host, remotefile, fd, port, &option);
+ #ifdef CONFIG_FEATURE_CLEAN_UP
+       if (!(fd == fileno(stdout) || fd == fileno(stdin))) {
+@@ -582,3 +980,18 @@
+ #endif
+       return(result);
+ }
++
++
++#ifdef CONFIG_FEATURE_TFTP_DEBUG
++
++#include <sys/time.h>
++
++static void
++printtime(void)
++{
++      struct timeval tv;
++      gettimeofday(&tv, NULL);
++      printf("%11lu.%06lu ", tv.tv_sec, tv.tv_usec);
++}
++
++#endif