- Jenkins CI
- Azure DevOps
- GitHub Actions
Available for Enterprise subscriptions
Origin verification allows trusted build systems to provide reliable origin metadata with your signing requests, so that SignPath can execute advanced policies based on trusted information.
Origin verification results in additional confidence for information in signing reqeusts, whether used for inspection or for policies. The feature is designed for use in enterprise scenarios, where policies and security controls need to be administered, enforced and audited centrally, while development teams still maintain full control over their projects. The ultimate goal of origin verification is to enable signing policies based on source code reviews.
The same principles are applied for Open Source signing, where SignPath Foundation provides certificates to individual OSS projects. Origin verification ensures that the Foundation’s signing policies are observed while leaving full control over repositories and build configurations with the OSS teams.
Origin verification verifies the following information:
- Source code repository URL as specified in the SignPath project
- Branch as specified in the signing policy
- Commit version
- Build job URL as provided by the CI system
- Reproducability checks that the build process is completely determined by the source code repository
Verification of reproducability depends on the CI system used. Typical verifications include:
- Build settings are fully determined by a configuration file under source control
- No manual overrides of critical build settings in CI system’s build job
- Prevent caching from previous (possibly unverified) builds
In order to use origin verification, a Trusted Build System must be configured and linked to the project.
Enable additional restrictions for signing policies that use release certificates:
- Select Verify origin to make sure that only verified builds can be signed
- Define source code review policies for branches that are supposed to be used for production releases. Use the Allowed branch names setting to make sure that a signing policy can only be used for specified branches. Typical settings include
- If you need to be able to sign other builds under special circumstances, consider adding another signing policy with strong approval requirements (e.g. 2 out of n).
Note that a build script or makefile can download any software from the Internet and include it as a build artifact. SignPath cannot possibly detect or prevent this, but it can make sure that any such evasion will be visible in the source code repository.
Make sure that your source code review policy includes CI configuration, build scripts, and makefiles. External content should not be accepted in reviews.
See the signing policy documentation for some ideas on how to secure your build pipelines using origin verification.
A connector is available that connects Jenkins CI as a Trusted Build System.
This connector ensures that
- A build was actually performed by a specific Jenkins CI instance, not by some other entity in possession of the API token
- Origin metadata is provided by Jenkins CI, not the build script, and can therefore not be forged
- The artifact is stored as an immutable Jenkins artifact before it is submitted for signing
Contact firstname.lastname@example.org for the connector and documentation.
The AppVeyor connector is built into SignPath and connects to appveyor.com.
- AppVeyor is available based on the configuration of your SignPath organization. You don’t need to add it on the Trusted Build Systems page.
- It must still be linked to each project (see below)
A customizable connector for AppVeyor Server will be provided in the future.
Prerequisites and restrictions
In order to ensure Origin Verification, you cannot submit a signing request from an unfinished build. Instead, you have to finish the build job without signing, and then trigger a signing request with origin verification. When signing is completed, you can use a Webhook handler for further processing, such as uploading the signed artifact to a repository.
The following checks are performed:
- No additional scripts may be executed during the build step and no cache entries may be used (so that the build remains fully traceable and is only built from the repository). The scripts must be all set to off at the bottom of the project settings page on AppVeyor.
- The build settings may not be modified between starting the AppVeyor build and calling SignPath.io
- The build configuration must be stored in the root directory under the name
.appveyor.yml(no custom name is allowed to be set under Project settings and Custom configuration .yml file name)
- For Open Source subscriptions, the AppVeyor project and the Git repository must be public.
These checks are performed to ensure that the binary artifacts result purely from the specified source code.
Is the following list complete? see https://www.appveyor.com/docs/build-configuration/#generic-git-repositories-and-yaml
At the moment those supported are: GitHub (hosted and on-premises), Bitbucket (hosted and on-premises), GitLab (hosted and on-premises), Azure DevOps, Kiln and Gitea.
This figure shows the secrets that must be shared between AppVeyor.com and SignPath.io:
Add an AppVeyor integration to a SignPath project
SignPath.io must authenticate against Appveyor to retrieve the build artifacts
Encrypt the SignPath API token in AppVeyor
AppVeyor lets you encrypt secret values. You can then safely use the encrypted string in your appveyor.yaml file
Add a deploy Webhook
Append this to your appveyor.yaml file:
Attached build documentation
SignPath adds the following information to packages:
- For NuGet packages:
- The build settings are stored in an AppVeyorSettings.json file in the root of the NuGet package
- The commit hash and repository URL are written to the metadata of the NuGet package
These steps allow consumers of the signed artifact to verify source code version and build settings.
Contact email@example.com for our Azure DevOps connector with origin verification support.
Contact firstname.lastname@example.org for a preview version of our GitHub Actions connector with origin verification support.