Cannot convert value "Tls,Tls1,Tls2" to type "System.Net.SecurityProtocol.Type"

[arizvisa]

Description of Issue/Question

In salt-bootstrap.ps1, the System.Net.SecurityProtoclType::Tls1 and System.Net.SecurityProtoclType::Tls2 enumerations do not exist on .NET Framework 4.0. This means the following line of code at salt-bootstrap.ps1:102 has an undocumented dependency;

[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]'Tls,Tls11,Tls12''

This results in the following error/backtrace:

Cannot convert value "Tls,Tls11,Tls12" to type "System.Net.SecurityProtocolType due to invalid enumeration values. Specify one of the following enumeration values and try again. The possible enumeration values are "Ssl3, Tls".
Downloading Salt minion installer Salt-Minion--AMD64-Setup.exe
At C:\Users\vagrant\AppData\Local\Temp\salt\bootstrap-salt.ps1:103 char:87
    + [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType] <<<< 'Tls,Tls11,Tls12'
    + CategoryInfo          : NotSpecified: (:) [], RuntimeException
    + FullyQualifiedErrorId : RuntimeException

You could wrap it in an exception handler and assign the constants directly to remain independent of the available .NET framework versions.

System.Net.SecurityProtocolType.Ssl3 -- 48 -- 0x30
System.Net.SecurityProtocolType.Tls -- 192 -- 0xC0
System.Net.SecurityProtocolType.Tls11 -- 768 -- 0x300
System.Net.SecurityProtocolType.Tls12 -- 3072 -- 0xC00

Setup

Use .NET Framework 4.0

Steps to Reproduce Issue

Run salt-bootstrap.ps1

Versions and Systems

Salt-Bootstrap.ps1 doesn't have a version parameter, but the url it's being requested from is https://raw.githubusercontent.com/saltstack/salt-bootstrap/stable/bootstrap-salt.ps1, and the latest commit is c252c74.

[arizvisa]

Ftr, this issue was actually introduced by the latest commit c252c74

[twangboy]

What version of Windows are you running?

[twangboy]

After investigating a little further, even if you set those constants directly, the version of .NET installed on Windows 7 by default still does not support them. Whether you set the text value (Tls12) or the flag value (0xC00). The only way to install using the bootstrap script is to upgrade .NET to a later version that supports Tls1.2. That's .NET 4.5 apparently.

[twangboy]

Also this KB will apparently enable Tls12 on Windows 7: KB3154518

[arizvisa]

In PR boxcutter/windows#201, we're explicitly patching out Tls12 to work around this issue and will probably end up linking to a previous commit if you guys choose to remove W7 out of your support matrix.