server: make nbf < iat to account for client clock skew #76
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mostlygeek
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mostlygeek
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Oct 1, 2025
| return | ||
| } | ||
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| now := time.Now() |
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just moved a few lines below and renamed now to iat - which is more descriptive of its use
mostlygeek
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Oct 1, 2025
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| // values for exp, nbp and iat claims | ||
| iat := time.Now() |
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these are reused in the JWT token tsClaims as well as in updating the AuthRequest
mostlygeek
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Oct 1, 2025
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| // Create a refresh token from the access token with longer validity | ||
| rtAuth := *ar // copy the authRequest | ||
| rtAuth.ValidTill = iat.Add(RefreshTokenDuration) |
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refresh tokens have a longer duration. Though we can probably tweak the scopes it has (future PR) to be less permissive.
mostlygeek
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Oct 1, 2025
| fmt.Printf("❌ Error verifying ID Token: %v\n", err) | ||
| os.Exit(1) | ||
| } | ||
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add checks in the verifier around the changed iat, exp, nbf logic
mikeodr
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Oct 2, 2025
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LGTM, one minor logging fix for clarity if you agree.
Set the nbf (not before) claim to be a 5 minutes before the iat (issued at) claim to account for clock skew between tsidp and clients. Fixes #73 Signed-off-by: Benson Wong <benson@tailscale.com>
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Set the nbf (not before) claim to be a 5 minutes before the iat (issued at) claim to account for clock skew between tsidp and clients.
Fixes #73