Rework SslStream API

[josesimoes]

Description

• Remove SslVerification from method parameters. It's now exposed as property.
• Rework methods to replace X509 certificate collections to single instance.
• Rework methods to use parameters matching the .NET API.
• Rework calls to SslNative accordingly.

Motivation and Context

• No point on using a certificate collection on embedded devices for authentication. If not on the CA root certificate store, the usual use case is to use a single specific certificate to authenticate.
• The default authentication option was not to validate certificate, which is clearly, a bad practice.
• The new default behaviour is now to authenticate. The SslVerification property allow a developer to change that behaviour, if needed.
• API is now inline with the .NET one.

How Has This Been Tested?

• SSL sample pack from sample repo running on a STM32F769I-DISCO.

Screenshots

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: José Simões jose.simoes@eclo.solutions

[nfbot]

Hi @josesimoes,

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Thank you for your contribution!

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