Proposed changes

A subscription with an older server can not decode a well known extension object because it doesn't set the length of the extension object. Based on fuzz testing, the length check has been changed to be an exact match.

Fix: Allow a value of -1 for the length

Also improve some internal calls to Safe Read functions by calling not via the interface.

Related Issues

• Fixes Siemens TP1200 v14 -- OPCUA Stack v1.5.374.126 #2866

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Further comments

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