website/docs/cli/plugins/signing.mdx
:::warning Note OpenTofu only authenticates provider plugins fetched from a registry. :::
OpenTofu providers installed from the Registry are cryptographically signed and the signature is verified at time of installation.
OpenTofu does NOT support fetching and using unsigned binaries, but you can manually install unsigned binaries. You should take extreme care when doing so as no programmatic authentication is performed.
OPENTOFU_ENFORCE_GPG_VALIDATION=falseA temporary change has been introduced to skip GPG validation under specific conditions:
While this offers operational flexibility, it does reduce the level of security assurance for affected packages. Users who prioritize security should set the OPENTOFU_ENFORCE_GPG_VALIDATION environment variable to true to enforce GPG validation of all providers.
Future Removal: We intend to remove this feature once all GPG keys are populated in the default registry, reverting to a strict GPG validation process for all providers.
OPENTOFU_ENFORCE_GPG_EXPIRATION=falseMany older keys present in the registry have expired and are no longer strictly valid. Historically, Terraform has not cared about the expiration date of keys in the registry and has ignored that field. When switching to a new crypto library, this functionality was
made available. For legacy reasons, this is currently disabled by default (set to false), but may default to true in a future release as workflows are built into the registry for keeping keys up to date.