Scribe GitHub Action for `valint bom`

Scribe offers the use of GitHub Actions to enable the embedding of evidence collection and integrity validation into your pipeline as a way to help secure your software supply chain.

valint bom is used to collect evidence and generate an SBOM.

Further documentation GitHub integration.

Bom Action

The command allows users to generate sbom and third party evidence.

CycloneDX 1.4 SBOM support.
Generates detailed SBOMs for images, directories, files and git repositories targets.
Store and manage evidence on Scribe service.
Attach evidence to any OCI registry.
Generate evidence directly from your private OCI registry.
Extensive SBOM component relation graph including, file to package, file and package to layer, commit history and file to commit relations.
SBOM including package CPEs and Licensing information.
Customizable SBOM with environments, labels.
Customizable SBOM with your required component groups.
Attach any external reports to your SBOM.
Signing - Generate In-Toto Attestation.
Support Sigstore keyless verifying as well as GitHub workload identity.
Attach GitHub workflows environment context (git url , commit, workflow, job, run id ..).

Containerized actions limit's the ability to generate evidence on a target located outside the working directory (directory or git targets).
To overcome the limitation install tool directly - installer.

Input arguments

  target:
    description: Target object name format=[<image:tag>, <dir path>, <git url>]
    required: true
  attach-regex:
    description: Attach files content by regex
  attest-config:
    description: Attestation config path
  attest-default:
    description: Attestation default config, options=[sigstore sigstore-github x509 x509-env kms pubkey]
  author-email:
    description: Set author email
  author-name:
    description: Set author name
  author-phone:
    description: Set author phone
  ca:
    description: x509 CA Chain path
  cert:
    description: x509 Cert path
  components:
    description: Select sbom components groups, options=[metadata layers packages syft files dep commits]
  crl:
    description: x509 CRL path
  crl-full-chain:
    description: Enable Full chain CRL verfication
  depth:
    description: Git clone depth
  disable-crl:
    description: Disable certificate revocation verificatoin
  filter-regex:
    description: Filter out files by regex
  filter-scope:
    description: Filter packages by scope
  force:
    description: Force overwrite cache
  format:
    description: Evidence format, options=[cyclonedx-json cyclonedx-xml attest-cyclonedx-json statement-cyclonedx-json attest-slsa statement-slsa statement-generic attest-generic]
  git-auth:
    description: 'Git repository authentication info, [format: ''username:password'']'
  git-branch:
    description: Git branch in the repository
  git-commit:
    description: Git commit hash in the repository
  git-tag:
    description: Git tag in the repository
  key:
    description: x509 Private key path
  kms:
    description: Provide KMS key reference
  oci:
    description: Enable OCI store
  oci-repo:
    description: Select OCI custom attestation repo
  package-exclude-type:
    description: Exclude package type, options=[ruby python javascript java dpkg apk rpm go dotnet r rust binary sbom nix conan alpm cocoapods swift dart elixir php erlang github portage haskell kernel wordpress lua]
  package-group:
    description: Select package group, options=[index install all]
  package-type:
    description: Select package type, options=[ruby python javascript java dpkg apk rpm go dotnet r rust binary sbom nix conan alpm cocoapods swift dart elixir php erlang github portage haskell kernel wordpress lua]
  pass:
    description: Private key password
  payload:
    description: path of the decoded payload
  platform:
    description: Select target platform, examples=windows/armv6, arm64 ..)
  provenance:
    description: Include SLSA Provenance evidence
  pubkey:
    description: Public key path
  supplier-email:
    description: Set supplier email
  supplier-name:
    description: Set supplier name
  supplier-phone:
    description: Set supplier phone
  supplier-url:
    description: Set supplier url
  cache-enable:
    description: Enable local cache
  config:
    description: Configuration file path
  deliverable:
    description: Mark as deliverable, options=[true, false]
  env:
    description: Environment keys to include in evidence
  gate:
    description: Policy Gate name
  label:
    description: Add Custom labels
  level:
    description: Log depth level, options=[panic fatal error warning info debug trace]
  log-context:
    description: Attach context to all logs
  log-file:
    description: Output log to file
  output-directory:
    description: Output directory path
    default: ./scribe/valint
  output-file:
    description: Output file name
  pipeline-name:
    description: Pipeline name
  predicate-type:
    description: Custom Predicate type (generic evidence format)
  product-key:
    description: Product Key
  product-version:
    description: Product Version
  scribe-client-id:
    description: Scribe Client ID (deprecated)
  scribe-client-secret:
    description: Scribe Client Token
  scribe-disable:
    description: Disable scribe client
  scribe-enable:
    description: Enable scribe client (deprecated)
  scribe-url:
    description: Scribe API Url
  structured:
    description: Enable structured logger
  timeout:
    description: Timeout duration
  verbose:
    description: Log verbosity level [-v,--verbose=1] = info, [-vv,--verbose=2] = debug

Output arguments

  OUTPUT_PATH:
    description: 'evidence output file path'

Usage

Containerized action can be used on Linux runners as following

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@v1.5.12
  with:
    target: 'busybox:latest'

Composite Action can be used on Linux or Windows runners as following

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom-cli@v1.5.12
  with:
    target: 'hello-world:latest'

Use master instead of tag to automatically pull latest version.

1. Obtain a Scribe Hub API Token

Sign in to Scribe Hub. If you don't have an account you can sign up for free here.
Create a API token in Scribe Hub > Settings > Tokens. Copy it to a safe temporary notepad until you complete the integration.

Important

The token is a secret and will not be accessible from the UI after you finalize the token generation.

2. Add the API token to Github secrets

Set your Scribe Hub API token in Github with a key named SCRIBE_TOKEN as instructed in *GitHub instructions](https://docs.github.com/en/actions/security-guides/encrypted-secrets/ "GitHub Instructions")

3. Instrument your build scripts

Usage

name:  scribe_github_workflow

on: 
  push:
    tags:
      - "*"

jobs:
  scribe-sign-verify:
    runs-on: ubuntu-latest
    steps:
      - uses: scribe-security/action-bom@master
        with:
          target: [target]
          format: [attest, statement]
          scribe-client-secret: ${{ secrets.SCRIBE_TOKEN }}

      - uses: scribe-security/action-verify@master
        with:
          target: [target]
          input-format: [attest, statement]
          scribe-client-secret: ${{ secrets.SCRIBE_TOKEN }}

Configuration

If you prefer using a custom configuration file instead of specifying arguments directly, you have two choices. You can either place the configuration file in the default path, which is .valint.yaml, or you can specify a custom path using the config argument.

For a comprehensive overview of the configuration file's structure and available options, please refer to the CLI configuration documentation.

Attestations

Attestations allow you to sign and verify your targets.
Attestations allow you to connect PKI-based identities to your evidence and policy management.

Supported outputs:

In-toto statements CycloneDX SBOM (unsigned evidence).
In-toto attestations CycloneDX SBOM (signed evidence).

Select default configuration using --attest.default flag.
Select a custom configuration by providing cocosign field in the configuration or custom path using --attest.config. Scribe uses the cocosign library we developed to deal with digital signatures signing and verification.

See details of in-toto spec here.
See details of what attestations are and how to use them here.

By default GitHub actions use sigstore-github flow, GitHub provided workload identities, this will allow using the workflow identity (token-id permissions is required).

Storing Keys in Secret Vault

GitHub exposes secrets from its vault using environment variables, you may provide these environment as secret to Valint.

Paths names prefixed with env://[NAME] are read from the environment matching the name.

GitHub Secret Vault

X509 Signer enables the utilization of environments for supplying key, certificate, and CA files in order to sign and verify attestations. It is commonly employed in conjunction with Secret Vaults, where secrets are exposed through environments.

path names prefixed with env://[NAME] are extracted from the environment corresponding to the specified name.

For example the following configuration and Job.

Configuration File, .valint.yaml

attest:
  default: "" # Set custom configuration
  cocosign:
    signer:
        x509:
            enable: true
            private: env://SIGNER_KEY
            cert: env://SIGNER_CERT
            ca: env://COMPANY_CA
    verifier:
        x509:
            enable: true
            cert: env://SIGNER_CERT
            ca: env://COMPANY_CA

Job example

name:  github_vault_workflow

on: 
  push:
    tags:
      - "*"

jobs:
  scribe-sign-verify:
    runs-on: ubuntu-latest
    steps:
        uses: scribe-security/action-bom@master
        with:
          target: busybox:latest
          format: attest
        env:
          SIGNER_KEY: ${{ secrets.SIGNER_KEY }}
          SIGNER_CERT: ${{ secrets.SIGNER_CERT }}
          COMPANY_CA:  ${{ secrets.COMPANY_CA }}

        uses: scribe-security/action-verify@master
        with:
          target: busybox:latest
          input-format: attest
        env:
          SIGNER_CERT: ${{ secrets.SIGNER_CERT }}
          COMPANY_CA:  ${{ secrets.COMPANY_CA }}

Running action as non root user

By default, the action runs in its own pid namespace as the root user. You can change the user by setting specific USERID and USERNAME environment variables.

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    target: 'busybox:latest'
    format: json
  env:
    USERID: 1001
    USERNAME: runner

Details

Non root user with HIGH UID/GID

By default, the action runs in its own pid namespace as the root user. If the user uses a high UID or GID, you must specify all the following environment variables. You can change the user by setting specific USERID and USERNAME variables. Additionally, you may group the process by setting specific GROUPID and GROUP variables.

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    target: 'busybox:latest'
    format: json
  env:
    USERID: 888000888
    USERNAME: my_user
    GROUPID: 777000777
    GROUP: my_group

Platform-Specific Image Handling

The Valint tool is compatible with both Linux and Windows images. Set the desired platform using the 'platform' field in your configuration:

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    target: hello-world:latest
    platform: linux/amd64
    format: json

Docker is configured by default to pull images matching the runner's platform. For analyzing images across different platforms, you need to pull the image from the registry and specify the platform.

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    target: registry:hello-world:latest
    platform: windows/amd64
    format: json

Windows Runner Compatibility

On Windows Github runners, containerized actions are currently not supported. It's recommended to use CLI actions in such cases.

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom-cli@master
  with:
    target: hello-world:latest
    format: json

Basic examples

Attach sbom to product

Create SBOM for remote busybox:latest image and attach it to a specific product version.

- name: Generate cyclonedx json SBOM attached to a product
  uses: scribe-security/action-bom@master
  with:
    target: 'busybox:latest'
    product-key: my_product
    product-version: 3
    format: json

Set Git sbom as deliverable artifact

Create SBOM for Deliverable mongo-express/mongo-express Git repository.

- name: Generate cyclonedx json SBOM for a deliverable Git repo
  uses: scribe-security/action-bom@master
  with:
    target: git:https://github.com/mongo-express/mongo-express.git
    product-key: my_product
    product-version: 3
    deliverable: true
    format: json

Public registry image

Create SBOM for remote busybox:latest image.

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    target: 'busybox:latest'
    format: json

Docker built image

Create SBOM for image built by local docker image_name:latest.

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    type: docker
    target: 'image_name:latest'
    format: json
    force: true

Private registry image

Create SBOM for image hosted by a private registry.

DOCKER_CONFIG environment will allow the containerized action to access the private registry.

env:
  DOCKER_CONFIG: $HOME/.docker
steps:
  - name: Login to GitHub Container Registry
    uses: docker/login-action@v2
    with:
      registry: ${{ env.REGISTRY_URL }}
      username: ${{ secrets.REGISTRY_USERNAME }}
      password: ${{ secrets.REGISTRY_TOKEN }}

  - name: Generate cyclonedx json SBOM
    uses: scribe-security/action-bom@master
    with:
      target: 'scribesecurity.jfrog.io/scribe-docker-local/example:latest'
      force: true

Custom metadata

Custom metadata added to SBOM.

- name: Generate cyclonedx json SBOM - add metadata - labels, envs
  id: valint_labels
  uses: scribe-security/action-bom@master
  with:
      target: 'busybox:latest'
      format: json
      force: true
      env: test_env
      label: test_label
  env:
    test_env: test_env_value

NTIA Custom metadata

Custom NTIA metadata added to SBOM.

- name: Generate cyclonedx json SBOM - add NTIA metadata
  id: valint_ntia
  uses: scribe-security/action-bom@master
  with:
      target: 'busybox:latest'
      format: json
      force: true
      author-name: bob
      author-email: bob@company.com
      author-phone: 000
      supplier-name: alice
      supplier-url: company2.com
      supplier-email: alice@company2.com
      supplier-phone: 001

Save evidence as artifact

Using action OUTPUT_PATH output argument you can access the generated SBOM and store it as an artifact.

Use action output-file: <my_custom_path> input argument to set a custom output path.

- name: Generate cyclonedx json SBOM
  id: valint_json
  uses: scribe-security/action-bom@master
  with:
    target: 'busybox:latest'
    output-file: my_sbom.json
    format: json

- uses: actions/upload-artifact@v4
  with:
    name: scribe-sbom
    path: ${{ steps.valint_json.outputs.OUTPUT_PATH }}

- uses: actions/upload-artifact@v4
  with:
    name: scribe-evidence
    path: scribe/

Docker archive image

Create SBOM for local docker save ... output.

- name: Build and save local docker archive
  uses: docker/build-push-action@v2
  with:
    context: .
    file: .GitHub/workflows/fixtures/Dockerfile_stub
    tags: scribesecurity.jfrog.io/scribe-docker-local/example:latest
    outputs: type=docker,dest=stub_local.tar

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    type: docker-archive
    target: '/GitHub/workspace/stub_local.tar'

OCI archive image

Create SBOM for the local OCI archive.

- name: Build and save local oci archive
  uses: docker/build-push-action@v2
  with:
    context: .
    file: .GitHub/workflows/fixtures/Dockerfile_stub
    tags: scribesecurity.jfrog.io/scribe-docker-local/example:latest
    outputs: type=oci,dest=stub_oci_local.tar

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    type: oci-archive
    target: '/GitHub/workspace/stub_oci_local.tar'

Directory target

Create SBOM for a local directory.

- name: Create dir
  run: |
    mkdir testdir
    echo "test" > testdir/test.txt

- name: valint attest dir
  id: valint_attest_dir
  uses: scribe-security/action-bom@master
  with:
    type: dir
    target: 'testdir'

Git target

Create SBOM for mongo-express remote git repository.

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    type: git
    target: 'https://github.com/mongo-express/mongo-express.git'
    format: json

Create SBOM for my_repo local git repository.

- uses: actions/checkout@v3
  with:
    fetch-depth: 0
    path: my_repo

- name: Generate cyclonedx json SBOM
  uses: scribe-security/action-bom@master
  with:
    type: git
    target: 'my_repo'
    format: json

Attest target

Create and sign SBOM targets.
By default the sigstore-github flow is used, GitHub workload identity and Sigstore (Fulcio, Rekor).

Default attestation config Required id-token permission access.

job_example:
  runs-on: ubuntu-latest
  permissions:
    id-token: write
  steps:
    - name: valint attest
      uses: scribe-security/action-bom@master
      with:
          target: 'busybox:latest'
          format: attest

Attest File evidence

Create and sign file as evidence.
By default the sigstore-github flow is used, GitHub workload identity and Sigstore (Fulcio, Rekor).

Default attestation config Required id-token permission access.

job_example:
  runs-on: ubuntu-latest
  permissions:
    id-token: write
  steps:
    - name: valint attest
    uses: scribe-security/action-evidence@master
    with:
        target: './file.go'
        format: attest

Verify target

Verify targets against a signed attestation.

Default attestation config: sigstore-github - Sigstore (Fulcio, Rekor).
Valint will look for an SBOM describing the image to verify against.

- name: valint verify
  uses: scribe-security/action-verify@master
  with:
    target: 'busybox:latest'

Verify Policy flow - image target (Signed SBOM)

Full job example of a image signing and verifying flow.

 valint-busybox-test:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
      id-token: write
    steps:

      - uses: actions/checkout@v2
        with:
          fetch-depth: 0

      - name: valint attest
        id: valint_attest
        uses: scribe-security/action-bom@master
        with:
           target: 'busybox:latest'
           format: attest
           force: true

      - name: valint verify
        id: valint_verify
        uses: scribe-security/action-verify@master
        with:
           target: 'busybox:latest'

      - uses: actions/upload-artifact@v4
        with:
          name: valint-busybox-test
          path: scribe/valint

Verify Policy flow - Directory target (Signed SBOM)

Full job example of a directory signing and verifying flow.

  valint-dir-test:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
      id-token: write
    steps:

      - uses: actions/checkout@v2
        with:
          fetch-depth: 0

      - name: valint attest workdir
        id: valint_attest_dir
        uses: scribe-security/action-bom@master
        with:
           type: dir
           target: '/GitHub/workspace/'
           format: attest
           force: true

      - name: valint verify workdir
        id: valint_verify_dir
        uses: scribe-security/action-verify@master
        with:
           type: dir
           target: '/GitHub/workspace/'
      
      - uses: actions/upload-artifact@v4
        with:
          name: valint-workdir-evidence
          path: |
            scribe/valint      

Verify Policy flow - Git repository target (Signed SBOM)

Full job example of a git repository signing and verifying flow.

Support for both local (path) and remote git (URL) repositories.

  valint-dir-test:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
      id-token: write
    steps:

      - uses: actions/checkout@v3
        with:
          fetch-depth: 0

      - name: valint attest local repo
        id: valint_attest_dir
        uses: scribe-security/action-bom@master
        with:
           type: git
           target: '/GitHub/workspace/my_repo'
           format: attest
           force: true

      - name: valint verify local repo
        id: valint_verify_dir
        uses: scribe-security/action-verify@master
        with:
           type: git
           target: '/GitHub/workspace/my_repo'
      
      - uses: actions/upload-artifact@v4
        with:
          name: valint-git-evidence
          path: |
            scribe/valint      

Attest and verify evidence on OCI SBOM

Store any evidence on any OCI registry.
Support storage for all targets and both SBOM formats.

Use input variable format to select between supported formats.
Write permission to oci-repo is required.

valint-dir-test:
  runs-on: ubuntu-latest
  permissions:
    id-token: write
  env:
    DOCKER_CONFIG: $HOME/.docker
  steps:
    - uses: actions/checkout@v3
      with:
        fetch-depth: 0

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v2
        with:
          registry: ${{ env.REGISTRY_URL }}
          username: ${{ secrets.REGISTRY_USERNAME }}
          password: ${{ secrets.REGISTRY_TOKEN }}

      - uses: scribe-security/action-bom@master
        id: valint_attest
        with:
          target: busybox:latest
          force: true
          format: attest
          oci: true
          oci-repo: ${{ env.REGISTRY_URL }}/attestations    

Following actions can be used to verify a target over the OCI store.

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v2
        with:
          registry: ${{ env.REGISTRY_URL }}
          username: ${{ secrets.REGISTRY_USERNAME }}
          password: ${{ secrets.REGISTRY_TOKEN }}

      - uses: scribe-security/action-verify@master
        id: valint_attest
        with:
          target: busybox:latest
          input-format: attest
          oci: true
          oci-repo: ${{ env.REGISTRY_URL }}/attestations   

Read permission to oci-repo is required.

Install Valint (tool)

Install Valint as a tool

- name: install valint
  uses: scribe-security/action-installer@master

- name: valint run
  run: |
    valint --version
    valint bom busybox:latest

Alternative evidence stores

You can learn more about alternative stores here.

OCI Evidence store

Valint supports both storage and verification flows for attestations and statement objects utilizing OCI registry as an evidence store.

Using OCI registry as an evidence store allows you to upload, download and verify evidence across your supply chain in a seamless manner.

Related flags:

oci Enable OCI store.
oci-repo - Evidence store location.

Before you begin

Evidence can be stored in any accusable registry.

Write access is required for upload (generate).
Read access is required for download (verify).

You must first login with the required access privileges to your registry before calling Valint. For example, using docker login command or docker/login-action action.

Usage

name:  scribe_github_workflow

on: 
  push:
    tags:
      - "*"

jobs:
  scribe-sign-verify:
    runs-on: ubuntu-latest
    steps:

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v2
        with:
          registry: ${{ env.my_registry }}
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}

      - name:  Generate evidence step
        uses: scribe-security/action-bom@master
        with:
          target: [target]
          format: [attest, statement]
          oci: true
          oci-repo: [oci_repo]

      - name:  Verify policy step
        uses: scribe-security/action-verify@master
        with:
          target: [target]
          input-format: [attest, statement]
          oci: true
          oci-repo: [oci_repo]

.gitignore

It's recommended to add output directory value to your .gitignore file. By default add **/scribe to your .gitignore.

Bom Action​

Input arguments​

Output arguments​

Usage​

1. Obtain a Scribe Hub API Token​

2. Add the API token to Github secrets​

3. Instrument your build scripts​

Usage​

Configuration​

Attestations​

Storing Keys in Secret Vault​

Running action as non root user​

Platform-Specific Image Handling​

Windows Runner Compatibility​

Basic examples​

Alternative evidence stores​

Before you begin​

Usage​

.gitignore​

Other Actions​

Bom Action

Input arguments

Output arguments

Usage

1. Obtain a Scribe Hub API Token

2. Add the API token to Github secrets

3. Instrument your build scripts

Usage

Configuration

Attestations

Storing Keys in Secret Vault

Running action as non root user

Platform-Specific Image Handling

Windows Runner Compatibility

Basic examples

Alternative evidence stores

Before you begin

Usage

.gitignore

Other Actions