title: Find and replace strings in raw ASN.1 encoded data
body: <p>I have some ASN.1 BER encoded raw data which looks like this when opened in notepad++:
  <a href="http://i.stack.imgur.com/OJYNP.png" rel="nofollow">Sample ASN1 encoded data</a></p>
  
  <p>I believe it's in binary octect format so only the "IA5string" data types are readable/meaningful.</p>
  
  <p>I'm wanting to do a find and replace on certain string data that contains sensitive information (phone numbers, IP address, etc), in order to scramble and anonymise it, while leaving the rest of the encoded data intact.</p>
  
  <p>I've made a python script to do it and it will work fine on plain text data, but having encoding/decoding issues when trying to read/write files in this encoded format, I guess since it contains octect values outside the ASCII range.</p>
  
  <p>What method would I need to use to import this data, do find &amp; replace on the strings to create a modified file that leaves everything else intact? i think it should be possible without completely decoding the raw ASN.1 data with a schema, since I only need to work on the IA5String data types</p>
  
  <p>Thanks</p>