Forum Discussion

Stephen Bell's avatar
Stephen Bell
Iron Contributor
Oct 06, 2016

Transport rule for message encryption with regex

Hello all,    I am looking to setup a transport rule in the GUI for message encryption.  I have already tested that encryption is configured correctly as I have a rule that I was playing with which...
exchange online
  • Chris Brown's avatar
    Chris Brown
    Oct 06, 2016

    I am by no means a regex expert, but a quick google and a bit of trial and error suggests the following may work:

     

    (?:^|\W|\w)\[encrypt\](?:$|\W|\w)

     

    Test in PowerShell:

    $regex = "(?:^|\W|\w)\[encrypt\](?:$|\W|\w)"

"### Should be true ###"
"[encrypt]" -match $regex
"[ENCRYPT]" -match $regex
"[Encrypt]" -match $regex
"[encrypt] test" -match $regex
"test [encrypt]" -match $regex
"test[encrypt]" -match $regex
"[encrypt]test" -match $regex
"### Should be false ###"
"[encr1ypt]" -match $regex
"do not encrypt" -match $regex

    Which returns

    ### Should be true ###
True
True
True
True
True
True
True
### Should be false ###
False
False
Chris Brown's avatar
Chris Brown
Iron Contributor
Oct 06, 2016

I am by no means a regex expert, but a quick google and a bit of trial and error suggests the following may work:

 

(?:^|\W|\w)\[encrypt\](?:$|\W|\w)

 

Test in PowerShell:

$regex = "(?:^|\W|\w)\[encrypt\](?:$|\W|\w)"

"### Should be true ###"
"[encrypt]" -match $regex
"[ENCRYPT]" -match $regex
"[Encrypt]" -match $regex
"[encrypt] test" -match $regex
"test [encrypt]" -match $regex
"test[encrypt]" -match $regex
"[encrypt]test" -match $regex
"### Should be false ###"
"[encr1ypt]" -match $regex
"do not encrypt" -match $regex

Which returns

### Should be true ###
True
True
True
True
True
True
True
### Should be false ###
False
False

Resources