Log HTTPs cert info on startup

[natemcmaster]

Kestrel logs endpoint when the server starts, but doesn't log which certificates were used. Now that Kestrel endpoints and certs can be configured from a file aspnet/KestrelHttpServer#2186, it would be nice to show console info to help users identify if their config was correctly used.

Some ideas:

From store, show friendly name

Now listening on: https://localhost:5001
Using server certificate: "ASP.NET Core HTTPS development certificate" from cert:\CurrentUser\My

From store, show subject

Now listening on: https://localhost:5001
Using server certificate: CN=localhost, cert:\CurrentUser\My

From store, include more info like thumbprint

Now listening on: https://localhost:5001
Using server certificate: CN=localhost, cert:\CurrentUser\My, 52A477BBEDE8DFDEB699106D5FFB8FE89F9BF790

From file

Now listening on: https://localhost:5001
Using server certificate: C:\dev\test\cert.pfx

Multiple certs

Now listening on: https://localhost:5002
Using server certificate: C:\dev\test\cert2.pfx
Now listening on: https://localhost:5001
Using server certificate: C:\dev\test\cert1.pfx

[davidfowl]

This seems like a good thing, thoughts @blowdart ?

[blowdart]

Aside from thumbprint yes (thumbprint is sha1, we don't like sha1)

Also add valid from and valid to or maybe the san (or first 5 hosts in the ssn, because those can get big)

[BrennanConroy]

Triage: This would be nice.
Issues: Certs wouldn't necessarily line up with the address they apply to. Can we get the store they came from?

Log.LogInfo("Loaded cert from X; <cert info>")

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[davidfowl]

Issues: Certs wouldn't necessarily line up with the address they apply to. Can we get the store they came from?

This is because hosting prints the addresses right?