Add SPS endpoint allowlist and secure probe client#672
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embetten
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Apr 27, 2026
cobya
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Apr 28, 2026
…oint - Add exact host 'vssps.codedev.ms' to AllowedSpsHosts so codedev PPE feeds can successfully exchange bearer tokens for session tokens - Replace silent null return on untrusted SPS endpoint with an UntrustedSpsEndpointException so the credential provider exits immediately instead of falling through to device-code polling - Add unit test for fail-fast behavior when SPS endpoint is untrusted - Add unit test coverage for vssps.codedev.ms allowlist entry
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cobya
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Apr 30, 2026
cobya
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Apr 30, 2026
cobya
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Apr 30, 2026
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This PR tightens how the credential provider handles discovery and token exchange as part of ongoing Entra identity hardening:
Credentialless probe client: Introduced HttpClientFactory.Probe, a dedicated HttpClient for discovery requests that does not set UseDefaultCredentials. This ensures Windows Integrated Authentication credentials are not sent when probing unknown endpoints for Azure DevOps headers.
HTTPS-only probing: Unknown hosts are now only probed over HTTPS. HTTP endpoints that aren't in the known hosts list are immediately treated as external without making a network call.
SPS endpoint allowlist: Added validation of the X-VSS-AuthorizationEndpoint header value before exchanging bearer tokens. The endpoint must match a known Azure DevOps SPS hostname (e.g., *.vssps.visualstudio.com, vssps.dev.azure.com). This prevents session token exchange against unexpected endpoints.
Testing:
258 unit tests passing (including 19 new tests for SPS allowlist validation)
Integration tested against a live Azure DevOps feed across all three target frameworks (net481, net6.0, net8.0) with broker, no-broker, and Entra token opt-in configurations