Amiga Tools 4/Amiga Tools 4.iso/tools/protect-your-privacy/p.g.p./pgpamiga/contrib/ced/decryptpgp.ced

Text File | 1996-02-26 | 5KB | 195 lines

/**********************************************************************/
/*                                                                    */
/*  DecryptPGP.ced - ARexx program that integrates Cygnus Editor and  */
/*                   the Pretty Good Privacy package, version 1.0     */
/*                                                                    */
/*  This program was tested to work with Cygnus Editor 3.5 and PGP    */
/*  version 2.3a patchlevel 3 by Peter Simons, but should work also   */
/*  with earlier versions of both PGP and CED.                        */
/*  If you want to decrypt a PGP message, you have to load it into    */
/*  CED, then run this macro, and sit comfortably enjoying the show   */
/*  until it finishes.                                                */
/*                                                                    */
/* This software is in Public Domain under GNU General Public License */
/*                                                                    */
/*  Author: Janusz A. Urbanowicz <[e-mail]>            */
/*                                                                    */
/*  History                                                           */
/*  Version 1.0 - first public release                                */
/*                                                                    */
/**********************************************************************/

/*
 *            $VER: DecryptPGP.ced 1.0 (4.07.1994)
 */


Trace Off

Options Results

packetstart = "'-----BEGIN PGP MESSAGE-----'"
packetend = "'-----END PGP MESSAGE-----'"
signedstart = "'-----BEGIN PGP SIGNED MESSAGE-----'"
signedend = "'-----END PGP SIGNATURE-----'"

cmdline = '+batchmode=on T:ced$pgp.tmp -o T:ced$plain.asc'
lf = '0A'X

packets = 0
lpackets = 0
scratch = 0

/*                               main()                           */
Address Command
'GetEnv >NIL: PGPPASS'
If rc ~= 0 Then
Do
    Address 'rexx_ced'
    okay2 "Your passphrase is not set in PGPPASS variable."||lf||,
    "It must be set temporarily for running PGP".||lf||,
    "Should it be deleted (for higher security) after use ??"
    If result = 1 then scratch = 1
    else scratch = 0
    okay1 'WARNING: Your passphrase will be visible when you type it in.'
    getstring "'  '  'Please enter passphrase.'"
    pgppass = result
    pgppass = Strip(pgppass,'B')
    Address Command
    'SetEnv PGPPASS '||'"'||pgppass||'"'
End

Address 'rexx_ced'
okay2 "Do you want to mark decrypted blocks"||lf||,
      "within the text ?"
mark = result

Do until lpackets == packets
    lpackets = packets
    scan(mark)
End
If packets = 0 Then okay1 "No PGP ASCII packet found."
Else okay1 "Found "||packets||" packet(s)."
Exit

/*                       End of main()                     */

scan: procedure expose lf cmdline scratch packets packetstart signedstart packetend signedend
Arg mark
Address 'rexx_ced'
If FindStart(packetstart) Then
Do
    If FindEnd(packetend) Then
    Do
        cut block
        menu 0 6 0 'T:ced$pgp.tmp' /* save block to file */
        decrypt_pkt(mark)
        Return 1
    End
End

If FindStart(signedstart) Then
Do
    If FindEnd(signedend) Then
    Do
        cut block
        menu 0 6 0 'T:ced$pgp.tmp' /* save block to file */
        decrypt_pkt(mark)
        Return 1
    End
End
Return 0

FindStart: procedure expose packets
Arg string
Address 'rexx_ced'
beg of file

Do FOREVER
    search for string
    If result = 1 Then
    Do
        status 59
        If result = (Length(string)-2) Then
        Do
            packets = packets +1
            mark block
            Return 1
        End
    End
    Else Return 0
End

FindEnd: procedure expose lf scratch
Arg string
Address = 'rexx_ced'
Do FOREVER
    search for string
    If result = 0 Then
    Do
        okay1 "Cannot find end of packet."||lf,
              "File is corrupted"
        Call quit
    End
    Else
    Do
        status 59
        If result = (Length(string)-2) Then
        Do
            down
            Return 1
        End
    End
End

decrypt_pkt: procedure expose cmdline lf scratch
arg mark

plainstart = "======== BEGIN OF PGP BLOCK ========"
plainend = "======== END OF PGP BLOCK ========"

Address Command
'PGP '||cmdline
If ~Exists('T:ced$plain.asc') Then
Do
    Address 'rexx_ced'
    include file 'T:ced$pgp.tmp'
    okay1 "Wrong passphrase !"
    Address Command
    Call quit
End
Else
Do
    Address 'rexx_ced'
    If mark == 1 Then
    Do
        text plainstart
        text lf
        up
        center line
        text plainend
        text lf
        up
        center line
        up
        beg of line
    End
    include file 'T:ced$plain.asc'
    status 21
    Call clean
    Return 1
End

clean: procedure
Address Command
If Exists('T:ced$pgp.tmp') Then 'Delete T:ced$pgp.tmp quiet'
If Exists('T:ced$plain.asc') Then 'Delete T:ced$plain.asc quiet'
If Exists('T:ced$pgp.tmp.bak') Then 'Delete T:ced$pgp.tmp.bak quiet'
If Exists('T:ced$pgp.tmp.info') Then 'Delete T:ced$pgp.tmp.info quiet'
Return 1

quit: procedure expose scratch
Call clean
If scratch == 1 Then 'Delete env:PGPPASS'
Exit 0