TFTP Server?

Mine is working from the pumpkin tftp client. Still needs to be cleaned up a bit, though:

  
 when RULE_INIT {  
 set blockdata(1) [binary format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
 set blockdata(2) [binary format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
 set blockdata(3) [binary format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
 set blockdata(4) [binary format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
 set blockdata(5) [binary format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
 set ::debug 1  
 }  
 when CLIENT_ACCEPTED {  
 binary scan [UDP::payload] xc opcode  
 if { $::debug } { log local0. "Opcode is $opcode" }  
 switch $opcode {  
 1 {  
 binary scan [UDP::payload] xxa* string  
 if { $::debug } { log local0. "String is $string" }  
 set file [lindex [split $string \000] 0]  
 set mode [lindex [split $string \000] 1]  
 if { $::debug} { log local0. "File is $file, Mode is $mode" }  
 if { $mode == "octet" || $mode ==  "netascii" } {  
 if { $file eq "test.txt" } {  
 if { $::debug } { log local0. "Request is valid" }  
 UDP::respond $::blockdata(1)  
 UDP::respond $::blockdata(2)  
 UDP::respond $::blockdata(3)  
 UDP::respond $::blockdata(4)  
 UDP::respond $::blockdata(5)  
 } else {  
 if { $::debug } { log local0. "Request is invalid" }  
 reject  
 }  
 } else {  
 if { $::debug } { log local0. "Invalid mode selected" }  
 reject   
 }  
 }   
 2 {  
 if { $::debug } { log local0. "Write request not supported here" }  
 }  
 3 {  
 if { $::debug } { log local0. "Data receipt not supported here" }  
 }  
 4 {  
 if { $::debug } { log local0. "Ack from client received" }  
 }  
 5 {  
 if { $::debug } { log local0. "Error: $string" }  
 }  
 default {  
 if { $::debug } { log local0. "Opcode $opcode is invalid" }  
 reject  
 }  
 }  
 }  
 

contents received are in the tftp file are:

!/usr/bin/perl -wÚuse strict;Úuse Net::SNMP qw(:snmp);ÚÚmy $usage = "ltm_intStat.pl ";ÚÚdie "Usage: $usage\n" if $ARGV != 3;ÚÚmy $host = $ARGV[0];Úmy $snmp_comm = $ARGV[1];Úmy $int = $ARGV[2];Úmy $interval = $ARGV[3];ÚÚchomp ($host , $snmp_comm , $int , $interval);ÚÚmy $ltm_InBytes_Index = "1.3.6.1.4.1.3375.2.1.2.4.4.3.1.3";Úmy $ltm_OutBytes_Index = "1.3.6.1.4.1.3375.2.1.2.4.4.3.1.5";ÚÚÚmy %int_map = ("1.1"=>".3.49.46.49",Ú "1.2"=>".3.49.46.50",Úã2Óâ"ã2ãC’ãCbãS"Í¢ãBÓâ"ã2ãC’ãCbãS""Í¢ãRÓâ"ã2ãC’ãCbãS2"Í¢ãbÓâ"ã2ãC’ãCbãSB"Í¢ãrÓâ"ã2ãC’ãCbãSR"Í¢ã‚Óâ"ã2ãC’ãCbãSb"Í¢ã’Óâ"ã2ãC’ãCbãSr"Í¢ãÓâ"ãBãC’ãCbãC’ãC‚"Í¢ãÓâ"ãBãC’ãCbãC’ãC’"Í¢ã"Óâ"ãBãC’ãCbãC’ãS"Í¢ã2Óâ"ãBãC’ãCbãC’ãS"Í¢ãBÓâ"ãBãC’ãCbãC’ãS""Í¢ãRÓâ"ãBãC’ãCbãC’ãS2"Í¢ "1.16"=>".4.49.46.49.54",Ú "2.1"=>".3.50.46.49",Ú "2.2"=>".3.50.46.50",Ú "2.3"=>".3.50.46.51",Ú "2.4"=>".3.50.46.52",Ú "mgmt"=>".4.109.103.109.116");ÚÚmy $ltm_intBytesIn = $ltm_InBytes_Index . $int_map{$int};Úmy $ltm_intBytesOut = $ltm_OutBytes_Index . $int_map{$int};ÚÚmy ($session, $error) = Net::SNMP->session(Ú -hostname => $host,Ú -community => $snmp_comm,Ú -port => 161,Ú -versionÓâw6æ×c&2rÍ¢Öæöæ&Æö6¶–ærÓâ

¢“½­¦–b‚FVf–æVBG6W76–öâ�¢½¢&–çB%&V6V—fVBæò4äÕ&W7öç6Rg&öÒF†÷7EÆâ½¢&–çB5DDU%"$W'&÷¢FW'&÷%Æâ½¢W†—BÓ½¢Ý­¢4vWBf—'7B–ç7Fæ6]¦×’Fö–G5óÒG6W76–öâÓævWE÷&WVW7B�¢×f&&–æFÆ—7BÓí¢²FÇFÕö–çD'—FW4–âÂFÇFÕö–çD'—FW4÷WEÒ“½­§6ÆVWF–çFW'fý­¢4vWB6V6öæB–ç7Fæ6]¦×’Fö–G5ó"ÒG6W76–öâÓævWE÷&WVW7B�¢×f&&–æFÆ—7BÓí¢²FÇFÕö–çD'—FW4–âÂ$ltm_intBytesOut] );ÚÚCalculate RatesÚmy $rate_in = ($oids_2->{$ltm_intBytesIn} - $oids_1->{$ltm_intBytesIn})*8 / $interval;Úmy $rate_out = ($oids_2->{$ltm_intBytesOut} - $oids_1->{$ltm_intBytesOut})*8 / $interval;ÚÚRound to integerÚ$rate_in = int($rate_in + .5);Ú$rate_out = int ($rate_out + .5);Úmy $rate_total = $rate_in + $rate_out;ÚÚPrint ResultsÚprint "\n\n\t$rate_in bits/second (IN)\n";Úprint "\t$rate_out bits/second (OUT)\n";Úprint "\t$rate_total bits/second (TOTAL)\n";

Haven't quite figured out the correct ascii to hex conversion. I am cutting into blocks first, then prepending the blocks with 0003xxxx, where xxxx is the blockID.

first of all, sorry for long line.

 

 

regarding the block problem

 

I did not check RFC but from packet trace it shows that both opcode and block-id use 2 bytes (short integer)

 

I think you may change it to something like this

 

 

set opcode 3

 

set blockid 1

 

set block [binary format SSH* $opcode $blockid [string range $::tftp_file 0 511] ]

 

UDP::respond $block

 

 

sorry again, not tested

 

Nat

The important stuff doesn't require a scroll... :-)

Ok, got the enconding figured out (I ripped it straight from the Tcl wiki). Here's the latest version.

  
 when CLIENT_ACCEPTED {   
      log local0. "Client connected from [IP::client_addr]"   
           binary scan [UDP::payload] xc opcode   
      log local0. "Opcode is $opcode"   
  
 if { $opcode == 1 } {   
      binary scan [UDP::payload] xxa* string   
      log local0. "String is $string"   
      set stringlist [split $string \000]   
      set file [lindex $stringlist 0]   
      set mode [lindex $stringlist 1]   
      log local0. "File is $file, Mode is $mode"   
  
      if { $mode != "octet" && $mode != "netascii" } {   
           reject   
  
      } else {   
           log local0. "Send the file!"   
  
           set data [binary format xcSa* 3  1 [string range $::tftp_file 0 511]]  
           log local0. "data = $data"  
           UDP::respond $data  
           }    
      } else { reject }   
 }  
 

So - incrementing the block ID (the "1" in the format command above) along with moving to the next 512 bytes is all that's left, modulo the changes citizen_elah has added that improve the protocol handling. This is pretty close. This will hopefully let us avoid having to embed the file into the actual rule.

OK, stuck again. I can't test it because I can't get it to parse right in the IRE. I'm missing something dumb here, but am going cross-eyed trying to find it. I'll post what I have and come back to it later after I clear my head.

(updated with some comments and a little visual cleanup)

  
 when CLIENT_ACCEPTED {  
     log local0. "Client connected from [IP::client_addr]"  
  binary scan [UDP::payload] xc opcode  
  log local0. "Opcode is $opcode"  
   
 if { $opcode == 1 } {  
  binary scan [UDP::payload] xxa* string  
  log local0. "String is $string"  
  set stringlist [split $string \000]  
  set file [lindex $stringlist 0]  
  set mode [lindex $stringlist 1]  
  log local0. "File is $file, Mode is $mode"  
   
 if { $mode != "octet" && $mode != "netascii" } {  
   
 reject  
   
 } else {  
   
 log local0. "Send the file!"  
  
 set block_id 1 
 set block_start 0 
 set block_len 512 
 set last 0 
  
 while { $last < 1 } { 
  
 log local0. "Block number $block_id" 
  
 set data [binary format xcSa* 3  $block_id [string range $::tftp_file $block_start $block_end]] 
  
  test for the last block - is it less than 512 bytes? If so, set a flag 
 if { [string length [string range $::tftp_file $block_start $block_end]] < 512 } then { 
  
 set last 1  
 } 
  
 log local0. "data = $data" 
  
  send the data 
  
 UDP::respond $data 
  
  increment block_id and shift the pointers to the 
  next block of data to send 
  
 incr block_id 
 block_start = block_len 
 set block_len = block_len + 512 
  
 } 
  
  We should be breaking out of the while loop now 
  The last block should have been sent. 
  
 } 
 }  
   
 } else { reject }  
  } 
  
  
 

Also - the file you drop into file.class has to follow the same format as in the iRule for returning HTML and graphics from an iRule:

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/LTMMaintenancePage.html

 

 

Pay particular attention to the treatment of text within the class file. No newlines are allowed, the block must be quoted, and there must be a trailing comma.

 

 

The warning about memory is also useful - the file will be read into (and served from) memory, so be wary of using this method to transfer giant files. Not that anyone would do that with TFTP, but you never know.

 

 

If you're using this iRule to serve binary data, there may need to be additional tweaks. You might have uuencode it first, then add the b64decode statement (see the above page and the lines for sending the PNG file).

Hey all, I wrote up a tech tip on the excellent work done here in the forum...great collaboration guys!

 

 

http://devcentral.f5.com/Default.aspx?tabid=63&articleType=ArticleView&articleId=343 Click here

your irule looks perfect.

 

just a comment that you may forward request onto server side which you will get 2 things in return

 

- server will send file from ephemeral port (not port 69)

 

- retry in case packet loss. you can have routine in SERVER_DATA that replies content based on ack it receives. if let say block 10 is loss, client will resend ack-for block 9. irule can detect block id from ack message and response with block "ack + 1"

 

 

however, I didnt read RFC, feel free to correct me if I am wrong.

natty76 -

 

 

The behavior you describe is correct. The way I read it, the server should wait for ACK(block) before sending block(ACK+1). In any case, the final rule looks great. I was a little surprised to not find one out there already.

Very nice collaboration, indeed.

 

 

Now if you guys can just figure out a way to serve the LTM ISO from a datagroup, you could build an "Enterprise Manager in an iRule" rule! :D

 

 

Aaron