Powershell regex for replacing text between two strings - regex

Question

I am trying to use a powershell script to change the password between two strings, I am running into two issues.
A complex password seems to break my regex, If I use something as simple as "TestPassword" the regex does what I expect. However using a more complex password "6QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI=" it breaks and results in
SSLEnabled="true" keystoreFile="C:\cert.pfx" $16QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI=" keystoreType="PKCS12"/>
instead of
SSLEnabled="true" keystoreFile="C:\cert.pfx" keystorePass="6QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI=" keystoreType="PKCS12"/>
I want to be less specific for the second match grouo, for example at the moment I must specify '" keystoreType' but I would prefer to be less specific and only specify the ending quote. This way if I change the position of the keystoreType parameter in the future I don't have to worry about changing the regex to suit.
Bellow is my powershell as it stands:
#Set new password in server.xml
$pass='6QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI='
$server_xml=".\server.xml"
(Get-Content $server_xml) -replace '(keystorePass=")(.*)(" keystoreType)',('$1{0}$3' -f "$pass") | Set-Content $server_xml
Bellow is an extract from my xml:
<Connector port="443" relaxedPathChars="[]|" relaxedQueryChars="[]|{}^\`"<>"
maxThreads="150" minSpareThreads="25" connectionTimeout="20000" enableLookups="false"
maxHttpHeaderSize="8192" protocol="HTTP/1.1" useBodyEncodingForURI="true" redirectPort="8443"
acceptCount="100" disableUploadTimeout="true" bindOnInit="false" secure="true" scheme="https"
proxyName="test.example.com" proxyPort="443"
SSLEnabled="true" keystoreFile="C:\cert.pfx" keystorePass="123abc" keystoreType="PKCS12"/>

Answer 1

Parse
As pointed out by #the four bird and #codextor in the comments; peeking and poking directly into a serialized string (e.g. XML) using string methods (like -Replace) is a bad idea. Instead you should use the related parser for searching and replacing which has an easier syntax, takes care of both your issues and other pitfalls (e.g. double quotes $pass='Test"123').
Security
There is even a protentional security risk by ignoring the related parsers as a user (which is assumed only allowed to supply a password) could inject a new property in your xml (connector) by supplying a password like:
$pass = 'MyPass" maxParameterCount="0'
Examples
$Xml = [Xml]'<Connector port="443" relaxedPathChars="[]|" relaxedQueryChars="[]|{}^\`"<>" maxThreads="150" minSpareThreads="25" connectionTimeout="20000" enableLookups="false" maxHttpHeaderSize="8192" protocol="HTTP/1.1" useBodyEncodingForURI="true" redirectPort="8443" acceptCount="100" disableUploadTimeout="true" bindOnInit="false" secure="true" scheme="https" proxyName="test.example.com" proxyPort="443" SSLEnabled="true" keystoreFile="C:\cert.pfx" keystorePass="123abc" keystoreType="PKCS12"/>'
$Xml.Connector.keystorePass = '6QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI='
$Xml.Connector
port : 443
relaxedPathChars : []|
relaxedQueryChars : []|{}^\`"<>
maxThreads : 150
minSpareThreads : 25
connectionTimeout : 20000
enableLookups : false
maxHttpHeaderSize : 8192
protocol : HTTP/1.1
useBodyEncodingForURI : true
redirectPort : 8443
acceptCount : 100
disableUploadTimeout : true
bindOnInit : false
secure : true
scheme : https
proxyName : test.example.com
proxyPort : 443
SSLEnabled : true
keystoreFile : C:\cert.pfx
keystorePass : 6QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI=
keystoreType : PKCS12
$Xml.OuterXml
<Connector port="443" relaxedPathChars="[]|" relaxedQueryChars="[]|{}^\`"<>" maxThreads="150" minSpareThreads="25" connectionTimeout="20000" enableLookups="false" maxHttpHeaderSize="8192" protocol="HTTP/1.1" useBodyEncodingForURI="true" redirectPort="8443" acceptCount="100" disableUploadTimeout="true" bindOnInit="false" secure="true" scheme="https" proxyName="test.example.com" proxyPort="443" SSLEnabled="true" keystoreFile="C:\cert.pfx" keystorePass="6QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI=" keystoreType="PKCS12" />
Addendum
(based on the additional info in the comments)
If there are more connectors in your xml, as e.g.:
$Xml = [Xml]'
<Connectors>
<Connector
port="80"
keystorePass="Pass1" />
<Connector
port="443"
keystorePass="Pass2" />
</Connectors>'
You might address the connectors like:
$Xml.Connectors.Connector[0].keystorePass = 'Pass80'
$Xml.Connectors.Connector.Where{ $_.port -eq '443' }.SetAttribute('keystorePass', 'Pass443')
$Xml.OuterXml
<Connectors><Connector port="80" keystorePass="Pass80" /><Connector port="443" keystorePass="Pass443" /></Connectors>

Answer 2

This person had a similar issue that I was able to use the regex in my code:
Hide passwords in string
I ended up with the following:
#Set new password in server.xml
$pass='6QAfD5PmMhWzUxTq1FO1bGJQQXRXu6tizN29h6MRUSI='
$server_xml=".\server.xml"
(Get-Content $server_xml) -replace '(?:(?<=keystorePass=")\S+(?="))',("$pass") | Set-Content $server_xml