Update test to match new error message format

Co-authored-by: bdehamer <398027+bdehamer@users.noreply.github.com>
Improve error message clarity for subject count limit
2026-02-17 16:04:17 +00:00 · 2026-02-17 16:03:23 +00:00 · 2026-02-17 16:01:54 +00:00 · 2026-02-17 16:00:46 +00:00 · 2026-02-17 15:57:37 +00:00 · 2026-02-17 07:55:08 -08:00
38 changed files with 89895 additions and 58253 deletions
@@ -1,4 +0,0 @@
-lib/
-dist/
-node_modules/
-coverage/
@@ -1,84 +0,0 @@
-env:
-  node: true
-  es6: true
-  jest: true
-
-globals:
-  Atomics: readonly
-  SharedArrayBuffer: readonly
-
-ignorePatterns:
-  - '!.*'
-  - '**/node_modules/.*'
-  - '**/dist/.*'
-  - '**/coverage/.*'
-  - '*.json'
-
-parser: '@typescript-eslint/parser'
-
-parserOptions:
-  ecmaVersion: 2023
-  sourceType: module
-  project:
-    - './.github/linters/tsconfig.json'
-    - './tsconfig.json'
-
-plugins:
-  - jest
-  - '@typescript-eslint'
-
-extends:
-  - eslint:recommended
-  - plugin:@typescript-eslint/eslint-recommended
-  - plugin:@typescript-eslint/recommended
-  - plugin:github/recommended
-  - plugin:jest/recommended
-
-rules:
-  {
-    'camelcase': 'off',
-    'eslint-comments/no-use': 'off',
-    'eslint-comments/no-unused-disable': 'off',
-    'i18n-text/no-en': 'off',
-    'import/no-namespace': 'off',
-    'import/no-unresolved': ['error', { 'ignore': ['csv-parse/sync'] }],
-    'no-console': 'off',
-    'no-unused-vars': 'off',
-    'prettier/prettier': 'error',
-    'semi': 'off',
-    '@typescript-eslint/array-type': 'error',
-    '@typescript-eslint/await-thenable': 'error',
-    '@typescript-eslint/ban-ts-comment': 'error',
-    '@typescript-eslint/consistent-type-assertions': 'error',
-    '@typescript-eslint/explicit-member-accessibility':
-      ['error', { 'accessibility': 'no-public' }],
-    '@typescript-eslint/explicit-function-return-type':
-      ['error', { 'allowExpressions': true }],
-    '@typescript-eslint/func-call-spacing': ['error', 'never'],
-    '@typescript-eslint/no-array-constructor': 'error',
-    '@typescript-eslint/no-empty-interface': 'error',
-    '@typescript-eslint/no-explicit-any': 'error',
-    '@typescript-eslint/no-extraneous-class': 'error',
-    '@typescript-eslint/no-for-in-array': 'error',
-    '@typescript-eslint/no-inferrable-types': 'error',
-    '@typescript-eslint/no-misused-new': 'error',
-    '@typescript-eslint/no-namespace': 'error',
-    '@typescript-eslint/no-non-null-assertion': 'warn',
-    '@typescript-eslint/no-require-imports': 'error',
-    '@typescript-eslint/no-unnecessary-qualifier': 'error',
-    '@typescript-eslint/no-unnecessary-type-assertion': 'error',
-    '@typescript-eslint/no-unused-vars': 'error',
-    '@typescript-eslint/no-useless-constructor': 'error',
-    '@typescript-eslint/no-var-requires': 'error',
-    '@typescript-eslint/prefer-for-of': 'warn',
-    '@typescript-eslint/prefer-function-type': 'warn',
-    '@typescript-eslint/prefer-includes': 'error',
-    '@typescript-eslint/prefer-string-starts-ends-with': 'error',
-    '@typescript-eslint/promise-function-async': 'error',
-    '@typescript-eslint/require-array-sort-compare': 'error',
-    '@typescript-eslint/restrict-plus-operands': 'error',
-    '@typescript-eslint/semi': ['error', 'never'],
-    '@typescript-eslint/space-before-function-paren': 'off',
-    '@typescript-eslint/type-annotation-spacing': 'error',
-    '@typescript-eslint/unbound-method': 'error'
-  }
@@ -1,10 +0,0 @@
-rules:
-  document-end: disable
-  document-start:
-    level: warning
-    present: false
-  line-length:
-    level: warning
-    max: 80
-    allow-non-breakable-words: true
-    allow-non-breakable-inline-mappings: true
@@ -1,9 +0,0 @@
-{
-  "$schema": "https://json.schemastore.org/tsconfig",
-  "extends": "../../tsconfig.json",
-  "compilerOptions": {
-    "noEmit": true
-  },
-  "include": ["../../__tests__/**/*", "../../src/**/*"],
-  "exclude": ["../../dist", "../../node_modules", "../../coverage", "*.json"]
-}
@@ -28,11 +28,11 @@ jobs:
    steps:
      - name: Checkout
        id: checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6.0.2

      - name: Setup Node.js
        id: setup-node
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6.2.0
        with:
          node-version-file: .node-version
          cache: npm
@@ -60,7 +60,7 @@ jobs:
      - if: ${{ failure() && steps.diff.outcome == 'failure' }}
        name: Upload Artifact
        id: upload
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
        with:
          name: dist
          path: dist/
@@ -21,11 +21,11 @@ jobs:
    steps:
      - name: Checkout
        id: checkout
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        uses: actions/checkout@0c366fd6a839edf440554fa01a7085ccba70ac98 # v5.0.1

      - name: Setup Node.js
        id: setup-node
-        uses: actions/setup-node@b39b52d1213e96004bfcb1c61a8a6fa8ab84f3e8 # v4.0.1
+        uses: actions/setup-node@6044e13b5dc448c55e2357c09f80417699197238 # v6.2.0
        with:
          node-version-file: .node-version
          cache: npm
@@ -58,7 +58,7 @@ jobs:
    steps:
      - name: Checkout
        id: checkout
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
+        uses: actions/checkout@0c366fd6a839edf440554fa01a7085ccba70ac98 # v5.0.1
      - name: Calculate subject digest
        id: subject
        env:
@@ -32,19 +32,19 @@ jobs:
    steps:
      - name: Checkout
        id: checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6.0.2

      - name: Initialize CodeQL
        id: initialize
-        uses: github/codeql-action/init@v3
+        uses: github/codeql-action/init@v4
        with:
          languages: ${{ matrix.language }}
          source-root: src

      - name: Autobuild
        id: autobuild
-        uses: github/codeql-action/autobuild@v3
+        uses: github/codeql-action/autobuild@v4

      - name: Perform CodeQL Analysis
        id: analyze
-        uses: github/codeql-action/analyze@v3
+        uses: github/codeql-action/analyze@v4
@@ -1,50 +0,0 @@
-name: Lint Codebase
-
-on:
-  pull_request:
-    branches:
-      - main
-  push:
-    branches:
-      - main
-
-permissions:
-  contents: read
-  packages: read
-  statuses: write
-
-jobs:
-  lint:
-    name: Lint Codebase
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout
-        id: checkout
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-
-      - name: Setup Node.js
-        id: setup-node
-        uses: actions/setup-node@v4
-        with:
-          node-version-file: .node-version
-          cache: npm
-
-      - name: Install Dependencies
-        id: install
-        run: npm ci
-
-      - name: Lint Codebase
-        id: super-linter
-        uses: super-linter/super-linter/slim@v7
-        env:
-          DEFAULT_BRANCH: main
-          FILTER_REGEX_EXCLUDE: dist/**/*
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          TYPESCRIPT_DEFAULT_STYLE: prettier
-          VALIDATE_ALL_CODEBASE: true
-          VALIDATE_JAVASCRIPT_STANDARD: false
-          VALIDATE_TYPESCRIPT_STANDARD: false
-          VALIDATE_JSCPD: false
@@ -1,22 +0,0 @@
-name: 'Publish Immutable Action Version'
-
-on:
-  release:
-    types: [published]
-
-permissions: {}
-
-jobs:
-  publish:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      id-token: write
-      packages: write
-
-    steps:
-      - name: Checking out
-        uses: actions/checkout@v4
-      - name: Publish
-        id: publish
-        uses: actions/publish-immutable-action@v0.0.4
@@ -1 +1 @@
-20.6.0
+24.5.0
@@ -18,12 +18,44 @@ Once the attestation has been created and signed, it will be uploaded to the GH
 attestations API and associated with the repository from which the workflow was
 initiated.

+When an attestation is created, the attestation is stored on the local
+filesystem used by the runner. For each attestation created, the filesystem path
+will be appended to the file `${RUNNER_TEMP}/created_attestation_paths.txt`.
+This can be used to gather all attestations created by all jobs during a the
+workflow.
+
 Attestations can be verified using the [`attestation` command in the GitHub
 CLI][5].

 See [Using artifact attestations to establish provenance for builds][9] for more
 information on artifact attestations.

+<!-- prettier-ignore-start -->
+> [!NOTE]
+> Artifact attestations are available in public repositories for all
+> current GitHub plans.
+>
+> To use artifact attestations in private or internal repositories, you must
+> be on a GitHub Enterprise Cloud plan.
+>
+> Artifact attestations are NOT supported on GitHub Enterprise Server.
+<!-- prettier-ignore-end -->
+
+## Attestation Modes
+
+This action supports three attestation modes, automatically detected based on
+the inputs you provide:
+
+<!-- markdownlint-disable MD013 -->
+
+| Mode           | When Used                                              | Description                                      |
+| -------------- | ------------------------------------------------------ | ------------------------------------------------ |
+| **Provenance** | No `sbom-path` or predicate inputs                     | Auto-generates [SLSA build provenance][10]       |
+| **SBOM**       | `sbom-path` is provided                                | Creates attestation from SPDX or CycloneDX SBOM  |
+| **Custom**     | `predicate-type`/`predicate`/`predicate-path` provided | User-supplied predicate                          |
+
+<!-- markdownlint-enable MD013 -->
+
 ## Usage

 Within the GitHub Actions workflow which builds some artifact you would like to
@@ -35,60 +67,71 @@ attest:
   permissions:
     id-token: write
     attestations: write
+     artifact-metadata: write
   ```

   The `id-token` permission gives the action the ability to mint the OIDC token
   necessary to request a Sigstore signing certificate. The `attestations`
-   permission is necessary to persist the attestation.
+   permission is necessary to persist the attestation. The `artifact-metadata`
+   permission is necessary to create the artifact storage record.

 1. Add the following to your workflow after your artifact has been built:

   ```yaml
-   - uses: actions/attest@v1
+   - uses: actions/attest@v4
     with:
       subject-path: '<PATH TO ARTIFACT>'
-       predicate-type: '<PREDICATE URI>'
-       predicate-path: '<PATH TO PREDICATE>'
   ```

-   The `subject-path` parameter should identify the artifact for which you want
-   to generate an attestation. The `predicate-type` can be any of the the
-   [vetted predicate types][3] or a custom value. The `predicate-path`
-   identifies a file containg the JSON-encoded predicate parameters.
+   By default, this generates a [SLSA build provenance][10] attestation. For
+   SBOM or custom attestations, see the [Attestation Modes](#attestation-modes)
+   section.

 ### Inputs

 See [action.yml](action.yml)

 ```yaml
- uses: actions/attest@v1
+- uses: actions/attest@v4
  with:
    # Path to the artifact serving as the subject of the attestation. Must
-    # specify exactly one of "subject-path" or "subject-digest". May contain
-    # a glob pattern or list of paths (total subject count cannot exceed 1024).
+    # specify exactly one of "subject-path", "subject-digest", or
+    # "subject-checksums". May contain a glob pattern or list of paths
+    # (total subject count cannot exceed 1024).
    subject-path:

    # SHA256 digest of the subject for the attestation. Must be in the form
    # "sha256:hex_digest" (e.g. "sha256:abc123..."). Must specify exactly one
-    # of "subject-path" or "subject-digest".
+    # of "subject-path", "subject-digest", or "subject-checksums".
    subject-digest:

-    # Subject name as it should appear in the attestation. Required unless
-    # "subject-path" is specified, in which case it will be inferred from the
-    # path.
+    # Subject name as it should appear in the attestation. Required when
+    # identifying the subject with the "subject-digest" input.
    subject-name:

-    # URI identifying the type of the predicate.
+    # Path to checksums file containing digest and name of subjects for
+    # attestation. Must specify exactly one of "subject-path", "subject-digest",
+    # or "subject-checksums".
+    subject-checksums:
+
+    # Path to the JSON-formatted SBOM file (SPDX or CycloneDX) to attest.
+    # File size cannot exceed 16MB. When provided, creates an SBOM attestation.
+    # Cannot be used together with "predicate-type", "predicate", or
+    # "predicate-path".
+    sbom-path:
+
+    # URI identifying the type of the predicate. Required when using "predicate"
+    # or "predicate-path" for custom attestations.
    predicate-type:

    # String containing the value for the attestation predicate. String length
    # cannot exceed 16MB. Must supply exactly one of "predicate-path" or
-    # "predicate".
+    # "predicate" when creating custom attestations.
    predicate:

    # Path to the file which contains the content for the attestation predicate.
    # File size cannot exceed 16MB. Must supply exactly one of "predicate-path"
-    # or "predicate".
+    # or "predicate" when creating custom attestations.
    predicate-path:

    # Whether to push the attestation to the image registry. Requires that the
@@ -96,6 +139,12 @@ See [action.yml](action.yml)
    # the "subject-digest" parameter be specified. Defaults to false.
    push-to-registry:

+    # Whether to create a storage record for the artifact.
+    # Requires that push-to-registry is set to true.
+    # Requires that the "subject-name" parameter specify the fully-qualified
+    # image name. Defaults to true.
+    create-storage-record:
+
    # Whether to attach a list of generated attestations to the workflow run
    # summary page. Defaults to true.
    show-summary:
@@ -109,9 +158,12 @@ See [action.yml](action.yml)

 <!-- markdownlint-disable MD013 -->

-| Name          | Description                                                    | Example                 |
-| ------------- | -------------------------------------------------------------- | ----------------------- |
-| `bundle-path` | Absolute path to the file containing the generated attestation | `/tmp/attestation.json` |
+| Name                 | Description                                                    | Example                                          |
+| -------------------  | -------------------------------------------------------------- | ------------------------------------------------ |
+| `attestation-id`     | GitHub ID for the attestation                                  | `123456`                                         |
+| `attestation-url`    | URL for the attestation summary                                | `https://github.com/foo/bar/attestations/123456` |
+| `bundle-path`        | Absolute path to the file containing the generated attestation | `/tmp/attestation.json`                          |
+| `storage-record-ids` | GitHub IDs for the storage records                             | `987654`                                         |

 <!-- markdownlint-enable MD013 -->

@@ -133,13 +185,13 @@ string cannot exceed 16MB.

 ## Examples

-### Identify Subject by Path
+### Provenance Attestation (Default)

-For the basic use case, simply add the `attest` action to your workflow and
-supply the path to the artifact for which you want to generate attestation.
+The simplest use case - just specify the artifact path and a SLSA build
+provenance attestation is automatically generated:

 ```yaml
-name: build-attest
+name: build-attest-provenance

 on:
  workflow_dispatch:
@@ -157,11 +209,36 @@ jobs:
      - name: Build artifact
        run: make my-app
      - name: Attest
-        uses: actions/attest@v1
+        uses: actions/attest@v4
        with:
          subject-path: '${{ github.workspace }}/my-app'
-          predicate-type: 'https://example.com/predicate/v1'
-          predicate: '{}'
+```
+
+### SBOM Attestation
+
+To create an SBOM attestation, provide the path to an SPDX or CycloneDX JSON
+file:
+
+```yaml
+- name: Generate SBOM
+  run: syft . -o spdx-json > sbom.spdx.json
+
+- uses: actions/attest@v4
+  with:
+    subject-path: '${{ github.workspace }}/my-app'
+    sbom-path: '${{ github.workspace }}/sbom.spdx.json'
+```
+
+### Custom Attestation
+
+For custom attestations, provide your own predicate type and content:
+
+```yaml
+- uses: actions/attest@v4
+  with:
+    subject-path: '${{ github.workspace }}/my-app'
+    predicate-type: 'https://example.com/predicate/v1'
+    predicate: '{}'
 ```

 ### Identify Multiple Subjects
@@ -170,7 +247,7 @@ If you are generating multiple artifacts, you can attest all of them at the same
 time by using a wildcard in the `subject-path` input.

 ```yaml
- uses: actions/attest@v1
+- uses: actions/attest@v4
  with:
    subject-path: 'dist/**/my-bin-*'
    predicate-type: 'https://example.com/predicate/v1'
@@ -184,19 +261,54 @@ Alternatively, you can explicitly list multiple subjects with either a comma or
 newline delimited list:

 ```yaml
- uses: actions/attest@v1
+- uses: actions/attest@v4
  with:
    subject-path: 'dist/foo, dist/bar'
 ```

 ```yaml
- uses: actions/attest@v1
+- uses: actions/attest@v4
  with:
    subject-path: |
      dist/foo
      dist/bar
 ```

+### Identify Subjects with Checksums File
+
+If you are using tools like
+[goreleaser](https://goreleaser.com/customization/checksum/) or
+[jreleaser](https://jreleaser.org/guide/latest/reference/checksum.html) which
+generate a checksums file you can identify the attestation subjects by passing
+the path of the checksums file to the `subject-checksums` input. Each of the
+artifacts identified in the checksums file will be listed as a subject for the
+attestation.
+
+```yaml
+- name: Calculate artifact digests
+  run: |
+    shasum -a 256 foo_0.0.1_* > subject.checksums.txt
+
+- uses: actions/attest@v4
+  with:
+    subject-checksums: subject.checksums.txt
+```
+
+<!-- markdownlint-disable MD038 -->
+
+The file referenced by the `subject-checksums` input must conform to the same
+format used by the shasum tools. Each subject should be listed on a separate
+line including the hex-encoded digest (either SHA256 or SHA512), a space, a
+single character flag indicating either binary (`*`) or text (` `) input mode,
+and the filename.
+
+<!-- markdownlint-enable MD038 -->
+
+```text
+b569bf992b287f55d78bf8ee476497e9b7e9d2bf1c338860bfb905016218c740  foo_0.0.1_darwin_amd64
+a54fc515e616cac7fcf11a49d5c5ec9ec315948a5935c1e11dd610b834b14dde  foo_0.0.1_darwin_arm64
+```
+
 ### Container Image

 When working with container images you can invoke the action with the
@@ -208,6 +320,10 @@ fully-qualified image name (e.g. "ghcr.io/user/app" or
 "acme.azurecr.io/user/app"). Do NOT include a tag as part of the image name --
 the specific image being attested is identified by the supplied digest.

+If the `push-to-registry` option is set to true, the Action will also
+emit an Artifact Metadata Storage Record. If you do not want to emit a
+storage record, set `create-storage-record` to `false`.
+
 > **NOTE**: When pushing to Docker Hub, please use "docker.io" as the registry
 > portion of the image name.

@@ -226,6 +342,7 @@ jobs:
      packages: write
      contents: read
      attestations: write
+      artifact-metadata: write
    env:
      REGISTRY: ghcr.io
      IMAGE_NAME: ${{ github.repository }}
@@ -247,13 +364,11 @@ jobs:
          push: true
          tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:latest
      - name: Attest
-        uses: actions/attest@v1
+        uses: actions/attest@v4
        id: attest
        with:
          subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          subject-digest: ${{ steps.push.outputs.digest }}
-          predicate-type: 'https://in-toto.io/attestation/release/v0.1'
-          predicate: '{"purl":"pkg:oci/..."}'
          push-to-registry: true
 ```

@@ -268,3 +383,4 @@ jobs:
 [8]: https://github.com/actions/toolkit/tree/main/packages/glob#patterns
 [9]:
  https://docs.github.com/en/actions/security-guides/using-artifact-attestations-to-establish-provenance-for-builds
+[10]: https://slsa.dev/spec/v1.0/provenance
@@ -0,0 +1,195 @@
+import { jest } from '@jest/globals'
+import type { Descriptor } from '@sigstore/oci'
+// Mock functions
+const mockGetOctokit = jest.fn()
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+const mockAttest = jest.fn<() => Promise<any>>()
+const mockCreateStorageRecord = jest.fn<() => Promise<number[]>>()
+const mockGetRegistryCredentials = jest.fn()
+const mockAttachArtifactToImage = jest.fn<() => Promise<Descriptor>>()
+
+// Mock @actions/github
+jest.unstable_mockModule('@actions/github', () => ({
+  getOctokit: mockGetOctokit,
+  context: {
+    repo: { owner: 'foo', repo: 'bar' },
+    payload: { repository: { visibility: 'private' } }
+  }
+}))
+
+// Mock @actions/attest
+jest.unstable_mockModule('@actions/attest', () => ({
+  attest: mockAttest,
+  createStorageRecord: mockCreateStorageRecord
+}))
+
+// Mock @sigstore/oci
+jest.unstable_mockModule('@sigstore/oci', () => ({
+  getRegistryCredentials: mockGetRegistryCredentials,
+  attachArtifactToImage: mockAttachArtifactToImage
+}))
+
+// Dynamic imports after mocking
+const { createAttestation, repoOwnerIsOrg } = await import('../src/attest')
+
+const subjectName = 'ghcr.io/foo/bar'
+const subjectDigest =
+  'sha256:7d070f6b64d9bcc530fe99cc21eaaa4b3c364e0b2d367d7735671fa202a03b32'
+
+const predicate = {
+  type: 'https://in-toto.io/attestation/release/v0.1',
+  params: {}
+}
+
+describe('repoOwnerIsOrg', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+  })
+
+  it('returns true when repo owner is an organization', async () => {
+    mockGetOctokit.mockReturnValue({
+      rest: {
+        repos: {
+          get: jest
+            .fn<() => Promise<{ data: { owner: { type: string } } }>>()
+            .mockResolvedValue({
+              data: { owner: { type: 'Organization' } }
+            })
+        }
+      }
+    })
+
+    const result = await repoOwnerIsOrg('gh-token')
+    expect(result).toBe(true)
+  })
+
+  it('returns false when repo owner is a user', async () => {
+    mockGetOctokit.mockReturnValue({
+      rest: {
+        repos: {
+          // eslint-disable-next-line @typescript-eslint/no-explicit-any
+          get: jest.fn<() => Promise<any>>().mockResolvedValue({
+            data: { owner: { type: 'User' } }
+          })
+        }
+      }
+    })
+
+    const result = await repoOwnerIsOrg('gh-token')
+    expect(result).toBe(false)
+  })
+})
+
+describe('createAttestation', () => {
+  beforeEach(() => {
+    jest.clearAllMocks()
+
+    // Default mock implementations
+    mockAttest.mockResolvedValue({
+      bundle: { mediaType: 'application/vnd.dev.sigstore.bundle.v0.3+json' },
+      certificate: 'cert',
+      tlogID: 'tlog-123',
+      attestationID: 'att-123'
+    })
+
+    mockGetRegistryCredentials.mockReturnValue({
+      username: 'user',
+      password: 'pass'
+    })
+
+    mockAttachArtifactToImage.mockResolvedValue({
+      digest: 'sha256:abc123',
+      mediaType: 'application/vnd.dev.sigstore.bundle.v0.3+json',
+      size: 100
+    })
+  })
+
+  describe('when createStorageRecord is false', () => {
+    it('skips storage record creation', async () => {
+      const subjects = [
+        {
+          name: subjectName,
+          digest: { sha256: subjectDigest.replace('sha256:', '') }
+        }
+      ]
+
+      const result = await createAttestation(subjects, predicate, {
+        sigstoreInstance: 'github',
+        pushToRegistry: true,
+        createStorageRecord: false,
+        githubToken: 'gh-token'
+      })
+
+      expect(result.attestationDigest).toBe('sha256:abc123')
+      expect(mockCreateStorageRecord).not.toHaveBeenCalled()
+    })
+  })
+
+  describe('when storage records are empty', () => {
+    beforeEach(() => {
+      mockGetOctokit.mockReturnValue({
+        rest: {
+          repos: {
+            // eslint-disable-next-line @typescript-eslint/no-explicit-any
+            get: jest.fn<() => Promise<any>>().mockResolvedValue({
+              data: { owner: { type: 'Organization' } }
+            })
+          }
+        }
+      })
+      mockCreateStorageRecord.mockResolvedValue([])
+    })
+
+    it('handles empty storage records gracefully', async () => {
+      const subjects = [
+        {
+          name: subjectName,
+          digest: { sha256: subjectDigest.replace('sha256:', '') }
+        }
+      ]
+
+      const result = await createAttestation(subjects, predicate, {
+        sigstoreInstance: 'github',
+        pushToRegistry: true,
+        createStorageRecord: true,
+        githubToken: 'gh-token'
+      })
+
+      expect(result.attestationDigest).toBe('sha256:abc123')
+    })
+  })
+
+  describe('when subject has unsupported protocol', () => {
+    beforeEach(() => {
+      mockGetOctokit.mockReturnValue({
+        rest: {
+          repos: {
+            // eslint-disable-next-line @typescript-eslint/no-explicit-any
+            get: jest.fn<() => Promise<any>>().mockResolvedValue({
+              data: { owner: { type: 'Organization' } }
+            })
+          }
+        }
+      })
+      mockCreateStorageRecord.mockResolvedValue([123])
+    })
+
+    it('handles unsupported protocol gracefully', async () => {
+      const subjects = [
+        {
+          name: 'http://registry.example.com/foo/bar',
+          digest: { sha256: subjectDigest.replace('sha256:', '') }
+        }
+      ]
+
+      const result = await createAttestation(subjects, predicate, {
+        sigstoreInstance: 'github',
+        pushToRegistry: true,
+        createStorageRecord: true,
+        githubToken: 'gh-token'
+      })
+
+      expect(result.attestationDigest).toBe('sha256:abc123')
+    })
+  })
+})
@@ -0,0 +1,190 @@
+import {
+  detectAttestationType,
+  validateAttestationInputs,
+  DetectionInputs
+} from '../src/detect'
+
+describe('detectAttestationType', () => {
+  const blankInputs: DetectionInputs = {
+    sbomPath: '',
+    predicateType: '',
+    predicate: '',
+    predicatePath: ''
+  }
+
+  describe('when no inputs are provided', () => {
+    it('returns provenance', () => {
+      expect(detectAttestationType(blankInputs)).toBe('provenance')
+    })
+  })
+
+  describe('when sbom-path is provided', () => {
+    it('returns sbom', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        sbomPath: '/path/to/sbom.json'
+      }
+      expect(detectAttestationType(inputs)).toBe('sbom')
+    })
+
+    it('returns sbom even when predicate inputs are also provided', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        sbomPath: '/path/to/sbom.json',
+        predicateType: 'https://example.com/predicate'
+      }
+      expect(detectAttestationType(inputs)).toBe('sbom')
+    })
+  })
+
+  describe('when predicate-type is provided', () => {
+    it('returns custom', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicateType: 'https://example.com/predicate'
+      }
+      expect(detectAttestationType(inputs)).toBe('custom')
+    })
+  })
+
+  describe('when predicate is provided', () => {
+    it('returns custom', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicate: '{}'
+      }
+      expect(detectAttestationType(inputs)).toBe('custom')
+    })
+  })
+
+  describe('when predicate-path is provided', () => {
+    it('returns custom', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicatePath: '/path/to/predicate.json'
+      }
+      expect(detectAttestationType(inputs)).toBe('custom')
+    })
+  })
+
+  describe('when predicate-type and predicate are provided', () => {
+    it('returns custom', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicateType: 'https://example.com/predicate',
+        predicate: '{}'
+      }
+      expect(detectAttestationType(inputs)).toBe('custom')
+    })
+  })
+})
+
+describe('validateAttestationInputs', () => {
+  const blankInputs: DetectionInputs = {
+    sbomPath: '',
+    predicateType: '',
+    predicate: '',
+    predicatePath: ''
+  }
+
+  describe('when no inputs are provided', () => {
+    it('does not throw', () => {
+      expect(() => validateAttestationInputs(blankInputs)).not.toThrow()
+    })
+  })
+
+  describe('when sbom-path is provided alone', () => {
+    it('does not throw', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        sbomPath: '/path/to/sbom.json'
+      }
+      expect(() => validateAttestationInputs(inputs)).not.toThrow()
+    })
+  })
+
+  describe('when sbom-path is combined with predicate-type', () => {
+    it('throws an error', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        sbomPath: '/path/to/sbom.json',
+        predicateType: 'https://example.com/predicate'
+      }
+      expect(() => validateAttestationInputs(inputs)).toThrow(
+        /Cannot specify sbom-path together with/
+      )
+    })
+  })
+
+  describe('when sbom-path is combined with predicate', () => {
+    it('throws an error', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        sbomPath: '/path/to/sbom.json',
+        predicate: '{}'
+      }
+      expect(() => validateAttestationInputs(inputs)).toThrow(
+        /Cannot specify sbom-path together with/
+      )
+    })
+  })
+
+  describe('when sbom-path is combined with predicate-path', () => {
+    it('throws an error', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        sbomPath: '/path/to/sbom.json',
+        predicatePath: '/path/to/predicate.json'
+      }
+      expect(() => validateAttestationInputs(inputs)).toThrow(
+        /Cannot specify sbom-path together with/
+      )
+    })
+  })
+
+  describe('when predicate is provided without predicate-type', () => {
+    it('throws an error', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicate: '{}'
+      }
+      expect(() => validateAttestationInputs(inputs)).toThrow(
+        /predicate-type is required/
+      )
+    })
+  })
+
+  describe('when predicate-path is provided without predicate-type', () => {
+    it('throws an error', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicatePath: '/path/to/predicate.json'
+      }
+      expect(() => validateAttestationInputs(inputs)).toThrow(
+        /predicate-type is required/
+      )
+    })
+  })
+
+  describe('when predicate-type and predicate are provided', () => {
+    it('does not throw', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicateType: 'https://example.com/predicate',
+        predicate: '{}'
+      }
+      expect(() => validateAttestationInputs(inputs)).not.toThrow()
+    })
+  })
+
+  describe('when predicate-type and predicate-path are provided', () => {
+    it('does not throw', () => {
+      const inputs: DetectionInputs = {
+        ...blankInputs,
+        predicateType: 'https://example.com/predicate',
+        predicatePath: '/path/to/predicate.json'
+      }
+      expect(() => validateAttestationInputs(inputs)).not.toThrow()
+    })
+  })
+})
@@ -1,22 +1,35 @@
 /**
 * Unit tests for the action's entrypoint, src/index.ts
 */
+import { jest } from '@jest/globals'

-import * as core from '@actions/core'
-import * as main from '../src/main'
+// Mock functions
+const mockRun = jest.fn()
+const mockGetInput = jest.fn()
+const mockGetBooleanInput = jest.fn()

-// Mock the action's entrypoint
-const runMock = jest.spyOn(main, 'run').mockImplementation()
-const getBooleanInputMock = jest.spyOn(core, 'getBooleanInput')
+// Mock @actions/core
+jest.unstable_mockModule('@actions/core', () => ({
+  getInput: mockGetInput,
+  getBooleanInput: mockGetBooleanInput
+}))
+
+// Mock ../src/main
+jest.unstable_mockModule('../src/main', () => ({
+  run: mockRun
+}))

 describe('index', () => {
  beforeEach(() => {
-    getBooleanInputMock.mockImplementation(() => false)
+    jest.clearAllMocks()
+    mockGetBooleanInput.mockReturnValue(false)
+    mockGetInput.mockReturnValue('')
  })
-  it('calls run when imported', async () => {
-    // eslint-disable-next-line @typescript-eslint/no-require-imports
-    require('../src/index')

-    expect(runMock).toHaveBeenCalled()
+  it('calls run when imported', async () => {
+    // Dynamic import after mocking
+    await import('../src/index')
+
+    expect(mockRun).toHaveBeenCalled()
  })
 })
@@ -5,55 +5,140 @@
 * Specifically, the inputs listed in `action.yml` should be set as environment
 * variables following the pattern `INPUT_<INPUT_NAME>`.
 */
-import * as core from '@actions/core'
-import * as github from '@actions/github'
-import { mockFulcio, mockRekor, mockTSA } from '@sigstore/mock'
-import * as oci from '@sigstore/oci'
-import fs from 'fs/promises'
-import nock from 'nock'
-import os from 'os'
-import path from 'path'
-import { MockAgent, setGlobalDispatcher } from 'undici'
-import { SEARCH_PUBLIC_GOOD_URL } from '../src/endpoints'
-import * as main from '../src/main'
+import type { Predicate } from '@actions/attest'
+import { jest } from '@jest/globals'
+import type { RunInputs } from '../src/main'

-// Mock the GitHub Actions core library
-const infoMock = jest.spyOn(core, 'info')
-const startGroupMock = jest.spyOn(core, 'startGroup')
-const setOutputMock = jest.spyOn(core, 'setOutput')
-const setFailedMock = jest.spyOn(core, 'setFailed')
+// Create mock functions before mocking modules
+const infoMock = jest.fn()
+const warningMock = jest.fn()
+const startGroupMock = jest.fn()
+const endGroupMock = jest.fn()
+const setOutputMock = jest.fn()
+const setFailedMock = jest.fn()
+const debugMock = jest.fn()

-// Ensure that setFailed doesn't set an exit code during tests
-setFailedMock.mockImplementation(() => {})
+// OCI mocks
+const getRegCredsMock = jest.fn()
+const attachArtifactMock = jest.fn()

-const summaryWriteMock = jest.spyOn(core.summary, 'write')
-summaryWriteMock.mockImplementation(async () => Promise.resolve(core.summary))
+// Attest mocks
+const attestMock = jest.fn()
+const createStorageRecordMock = jest.fn()

-// Mock the action's main function
-const runMock = jest.spyOn(main, 'run')
+// Local attest mocks
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+const createAttestationMock = jest.fn<() => Promise<any>>()
+const repoOwnerIsOrgMock = jest.fn()
+
+// Provenance mock
+const generateProvenancePredicateMock = jest.fn<() => Promise<Predicate>>()
+
+// GitHub context mock
+const mockContext = {
+  repo: { owner: 'foo', repo: 'bar' },
+  payload: { repository: { visibility: 'private' } }
+}
+const mockGetOctokit = jest.fn()
+
+// Summary mock with chainable methods
+const summaryMock = {
+  write: jest.fn().mockReturnThis(),
+  addRaw: jest.fn().mockReturnThis(),
+  addHeading: jest.fn().mockReturnThis(),
+  addLink: jest.fn().mockReturnThis(),
+  addTable: jest.fn().mockReturnThis(),
+  addBreak: jest.fn().mockReturnThis(),
+  addSeparator: jest.fn().mockReturnThis(),
+  addQuote: jest.fn().mockReturnThis(),
+  addCodeBlock: jest.fn().mockReturnThis(),
+  addList: jest.fn().mockReturnThis(),
+  addImage: jest.fn().mockReturnThis(),
+  addDetails: jest.fn().mockReturnThis(),
+  addEOL: jest.fn().mockReturnThis(),
+  emptyBuffer: jest.fn().mockReturnThis(),
+  stringify: jest.fn().mockReturnValue(''),
+  isEmptyBuffer: jest.fn().mockReturnValue(true),
+  clear: jest.fn().mockReturnThis()
+}
+
+// Mock @actions/core
+jest.unstable_mockModule('@actions/core', () => ({
+  info: infoMock,
+  warning: warningMock,
+  startGroup: startGroupMock,
+  endGroup: endGroupMock,
+  setOutput: setOutputMock,
+  setFailed: setFailedMock,
+  debug: debugMock,
+  summary: summaryMock
+}))
+
+// Mock @actions/github
+jest.unstable_mockModule('@actions/github', () => ({
+  context: mockContext,
+  getOctokit: mockGetOctokit
+}))
+
+// Mock @sigstore/oci
+jest.unstable_mockModule('@sigstore/oci', () => ({
+  getRegistryCredentials: getRegCredsMock,
+  attachArtifactToImage: attachArtifactMock
+}))
+
+// Mock @actions/attest
+jest.unstable_mockModule('@actions/attest', () => ({
+  attest: attestMock,
+  createStorageRecord: createStorageRecordMock
+}))
+
+// Mock ../src/attest
+jest.unstable_mockModule('../src/attest', () => ({
+  createAttestation: createAttestationMock,
+  repoOwnerIsOrg: repoOwnerIsOrgMock
+}))
+
+// Mock ../src/provenance
+jest.unstable_mockModule('../src/provenance', () => ({
+  generateProvenancePredicate: generateProvenancePredicateMock
+}))
+
+// Dynamic imports after mocking
+const { mockFulcio, mockRekor, mockTSA } = await import('@sigstore/mock')
+const fs = (await import('fs/promises')).default
+const nock = (await import('nock')).default
+const os = (await import('os')).default
+const path = (await import('path')).default
+const { MockAgent, setGlobalDispatcher } = await import('undici')
+const { run } = await import('../src/main')

 // MockAgent for mocking @actions/github
 const mockAgent = new MockAgent()
 setGlobalDispatcher(mockAgent)

-const defaultInputs: main.RunInputs = {
+const defaultInputs: RunInputs = {
  predicate: '',
  predicateType: '',
  predicatePath: '',
+  sbomPath: '',
  subjectName: '',
  subjectDigest: '',
  subjectPath: '',
+  subjectChecksums: '',
  pushToRegistry: false,
+  createStorageRecord: true,
  showSummary: true,
  githubToken: '',
  privateSigning: false
 }

 describe('action', () => {
-  // Capture original environment variables and GitHub context so we can restore
-  // them after each test
+  // Capture original environment variables so we can restore after each test
  const originalEnv = process.env
-  const originalContext = { ...github.context }
+  const originalContext = {
+    repo: { owner: 'foo', repo: 'bar' },
+    payload: { repository: { visibility: 'private' } }
+  }

  // Mock OIDC token endpoint
  const tokenURL = 'https://token.url'
@@ -65,13 +150,14 @@ describe('action', () => {
    'base64'
  )}.}`

-  const subjectName = 'registry/foo/bar'
+  const subjectName = 'ghcr.io/registry/foo/bar'
  const subjectDigest =
    'sha256:7d070f6b64d9bcc530fe99cc21eaaa4b3c364e0b2d367d7735671fa202a03b32'
  const predicate = '{}'
  const predicateType = 'https://in-toto.io/attestation/release/v0.1'

  const attestationID = '1234567890'
+  const storageRecordID = 987654321

  beforeEach(() => {
    jest.clearAllMocks()
@@ -81,14 +167,21 @@ describe('action', () => {
      .query({ audience: 'sigstore' })
      .reply(200, { value: oidcToken })

-    mockAgent
-      .get('https://api.github.com')
+    const pool = mockAgent.get('https://api.github.com')
+    pool
      .intercept({
        path: /^\/repos\/.*\/.*\/attestations$/,
        method: 'post'
      })
      .reply(201, { id: attestationID })

+    pool
+      .intercept({
+        path: /^\/orgs\/.*\/artifacts\/metadata\/storage-record$/,
+        method: 'post'
+      })
+      .reply(200, { storage_records: [{ id: storageRecordID }] })
+
    process.env = {
      ...originalEnv,
      ACTIONS_ID_TOKEN_REQUEST_URL: tokenURL,
@@ -106,7 +199,7 @@ describe('action', () => {
  })

  describe('when ACTIONS_ID_TOKEN_REQUEST_URL is not set', () => {
-    const inputs: main.RunInputs = {
+    const inputs: RunInputs = {
      ...defaultInputs,
      subjectDigest,
      subjectName,
@@ -121,9 +214,8 @@ describe('action', () => {
    })

    it('sets a failed status', async () => {
-      await main.run(inputs)
+      await run(inputs)

-      expect(runMock).toHaveReturned()
      expect(setFailedMock).toHaveBeenCalledWith(
        new Error(
          'missing "id-token" permission. Please add "permissions: id-token: write" to your workflow.'
@@ -134,17 +226,18 @@ describe('action', () => {

  describe('when no inputs are provided', () => {
    it('sets a failed status', async () => {
-      await main.run(defaultInputs)
+      await run(defaultInputs)

-      expect(runMock).toHaveReturned()
      expect(setFailedMock).toHaveBeenCalledWith(
-        new Error('One of subject-path or subject-digest must be provided')
+        new Error(
+          'One of subject-path, subject-digest, or subject-checksums must be provided'
+        )
      )
    })
  })

  describe('when the repository is private', () => {
-    const inputs: main.RunInputs = {
+    const inputs: RunInputs = {
      ...defaultInputs,
      subjectDigest,
      subjectName,
@@ -160,6 +253,16 @@ describe('action', () => {
        repo: { owner: 'foo', repo: 'bar' }
      })

+      // Mock createAttestation to return expected values
+      createAttestationMock.mockResolvedValue({
+        attestationID,
+        certificate:
+          '-----BEGIN CERTIFICATE-----\ntest\n-----END CERTIFICATE-----',
+        tlogID: 'tlog-123',
+        attestationDigest: 'sha256:123456',
+        bundle: { mediaType: 'application/vnd.dev.sigstore.bundle.v0.3+json' }
+      })
+
      await mockFulcio({
        baseURL: 'https://fulcio.githubapp.com',
        strict: false
@@ -168,46 +271,21 @@ describe('action', () => {
    })

    it('invokes the action w/o error', async () => {
-      await main.run(inputs)
+      await run(inputs)

-      expect(runMock).toHaveReturned()
-      expect(setFailedMock).not.toHaveBeenCalledWith()
-      expect(infoMock).toHaveBeenNthCalledWith(
-        1,
+      expect(setFailedMock).not.toHaveBeenCalled()
+      expect(infoMock).toHaveBeenCalledWith('Attestation type: Custom')
+      expect(infoMock).toHaveBeenCalledWith(
        expect.stringMatching(
          `Attestation created for ${subjectName}@${subjectDigest}`
        )
      )
-      expect(startGroupMock).toHaveBeenNthCalledWith(
-        1,
-        expect.stringMatching('GitHub Sigstore')
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        2,
-        expect.stringMatching('-----BEGIN CERTIFICATE-----')
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        3,
-        expect.stringMatching(/attestation uploaded/i)
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        4,
-        expect.stringMatching(attestationID)
-      )
-      expect(setOutputMock).toHaveBeenNthCalledWith(
-        1,
-        'bundle-path',
-        expect.stringMatching('attestation.json')
-      )
-      expect(setFailedMock).not.toHaveBeenCalled()
+      expect(createAttestationMock).toHaveBeenCalled()
    })
  })

  describe('when the repository is public', () => {
-    const getRegCredsSpy = jest.spyOn(oci, 'getRegistryCredentials')
-    const attachArtifactSpy = jest.spyOn(oci, 'attachArtifactToImage')
-
-    const inputs: main.RunInputs = {
+    const inputs: RunInputs = {
      ...defaultInputs,
      subjectDigest,
      subjectName,
@@ -224,69 +302,88 @@ describe('action', () => {
        repo: { owner: 'foo', repo: 'bar' }
      })

+      // Setup createAttestation mock
+      createAttestationMock.mockResolvedValue({
+        attestationID,
+        certificate:
+          '-----BEGIN CERTIFICATE-----\ntest\n-----END CERTIFICATE-----',
+        tlogID: 'tlog-123',
+        attestationDigest: 'sha256:123456',
+        bundle: { mediaType: 'application/vnd.dev.sigstore.bundle.v0.3+json' },
+        storageRecordIds: [storageRecordID]
+      })
+
      await mockFulcio({
        baseURL: 'https://fulcio.sigstore.dev',
        strict: false
      })
      await mockRekor({ baseURL: 'https://rekor.sigstore.dev' })

-      getRegCredsSpy.mockImplementation(() => ({
-        username: 'username',
-        password: 'password'
-      }))
-      attachArtifactSpy.mockImplementation(async () =>
-        Promise.resolve({
-          digest: 'sha256:123456',
-          mediaType: 'application/vnd.cncf.notary.v2',
-          size: 123456
-        })
-      )
+      mockGetOctokit.mockReturnValue({
+        rest: {
+          repos: {
+            get: jest
+              .fn<() => Promise<{ data: { owner: { type: string } } }>>()
+              .mockResolvedValue({
+                data: { owner: { type: 'Organization' } }
+              })
+          }
+        }
+      })
    })

    it('invokes the action w/o error', async () => {
-      await main.run(inputs)
+      await run(inputs)

-      expect(runMock).toHaveReturned()
      expect(setFailedMock).not.toHaveBeenCalled()
-      expect(getRegCredsSpy).toHaveBeenCalledWith(subjectName)
-      expect(attachArtifactSpy).toHaveBeenCalled()
-      expect(infoMock).toHaveBeenNthCalledWith(
-        1,
+      expect(createAttestationMock).toHaveBeenCalled()
+      expect(infoMock).toHaveBeenCalledWith('Attestation type: Custom')
+      expect(infoMock).toHaveBeenCalledWith(
        expect.stringMatching(
          `Attestation created for ${subjectName}@${subjectDigest}`
        )
      )
-      expect(startGroupMock).toHaveBeenNthCalledWith(
-        1,
-        expect.stringMatching('Public Good Sigstore')
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        2,
-        expect.stringMatching('-----BEGIN CERTIFICATE-----')
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        3,
-        expect.stringMatching(/signature uploaded/i)
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        4,
-        expect.stringMatching(SEARCH_PUBLIC_GOOD_URL)
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        5,
-        expect.stringMatching(/attestation uploaded/i)
-      )
-      expect(infoMock).toHaveBeenNthCalledWith(
-        6,
-        expect.stringMatching(attestationID)
-      )
-      expect(setOutputMock).toHaveBeenNthCalledWith(
-        1,
-        'bundle-path',
-        expect.stringMatching('attestation.json')
-      )
+    })
+
+    it('catches error when storage record creation fails and continues', async () => {
+      // Mock createAttestation to simulate storage record failure (but still succeed overall)
+      createAttestationMock.mockResolvedValue({
+        attestationID,
+        certificate:
+          '-----BEGIN CERTIFICATE-----\ntest\n-----END CERTIFICATE-----',
+        tlogID: 'tlog-123',
+        attestationDigest: 'sha256:123456',
+        bundle: { mediaType: 'application/vnd.dev.sigstore.bundle.v0.3+json' }
+        // No storageRecordIDs - simulates empty/failed storage record
+      })
+
+      await run(inputs)
+
+      expect(createAttestationMock).toHaveBeenCalled()
      expect(setFailedMock).not.toHaveBeenCalled()
    })
+
+    it('does not create a storage record when the repo is owned by a user', async () => {
+      // Mock createAttestation to not return storage record IDs
+      createAttestationMock.mockResolvedValue({
+        attestationID,
+        certificate:
+          '-----BEGIN CERTIFICATE-----\ntest\n-----END CERTIFICATE-----',
+        tlogID: 'tlog-123',
+        attestationDigest: 'sha256:123456',
+        bundle: { mediaType: 'application/vnd.dev.sigstore.bundle.v0.3+json' }
+      })
+
+      await run(inputs)
+
+      expect(setFailedMock).not.toHaveBeenCalled()
+      expect(createAttestationMock).toHaveBeenCalled()
+      expect(infoMock).toHaveBeenCalledWith(
+        expect.stringMatching(
+          `Attestation created for ${subjectName}@${subjectDigest}`
+        )
+      )
+    })
  })

  describe('when the subject count is greater than 1', () => {
@@ -328,19 +425,19 @@ describe('action', () => {
    })

    it('invokes the action w/o error', async () => {
-      const inputs: main.RunInputs = {
+      const inputs: RunInputs = {
        ...defaultInputs,
        subjectPath: path.join(dir, `${filename}-*`),
        predicateType,
        predicate,
        githubToken: 'gh-token'
      }
-      await main.run(inputs)
+      await run(inputs)

-      expect(runMock).toHaveReturned()
      expect(setFailedMock).not.toHaveBeenCalled()
+      expect(infoMock).toHaveBeenNthCalledWith(1, 'Attestation type: Custom')
      expect(infoMock).toHaveBeenNthCalledWith(
-        1,
+        2,
        expect.stringMatching('Attestation created for 5 subjects')
      )
    })
@@ -376,27 +473,204 @@ describe('action', () => {
    })

    it('sets a failed status', async () => {
-      const inputs: main.RunInputs = {
+      const inputs: RunInputs = {
        ...defaultInputs,
        subjectPath: path.join(dir, `${filename}-*`),
        predicateType,
        predicate,
        githubToken: 'gh-token'
      }
-      await main.run(inputs)
+      await run(inputs)

-      expect(runMock).toHaveReturned()
      expect(setFailedMock).toHaveBeenCalledWith(
        new Error(
-          'Too many subjects specified. The maximum number of subjects is 1024.'
+          'Too many subjects specified (>1024). The maximum number of subjects is 1024.'
        )
      )
    })
  })
+
+  describe('attestation type detection', () => {
+    describe('when sbom-path is provided with predicate inputs', () => {
+      it('sets a failed status for conflicting inputs', async () => {
+        const inputs: RunInputs = {
+          ...defaultInputs,
+          subjectDigest,
+          subjectName,
+          sbomPath: '/path/to/sbom.json',
+          predicateType: 'https://example.com/predicate',
+          githubToken: 'gh-token'
+        }
+
+        await run(inputs)
+
+        expect(setFailedMock).toHaveBeenCalledWith(
+          new Error(
+            'Cannot specify sbom-path together with predicate-type, predicate, or predicate-path'
+          )
+        )
+      })
+    })
+
+    describe('when predicate is provided without predicate-type', () => {
+      it('sets a failed status for missing predicate-type', async () => {
+        const inputs: RunInputs = {
+          ...defaultInputs,
+          subjectDigest,
+          subjectName,
+          predicate: '{}',
+          githubToken: 'gh-token'
+        }
+
+        await run(inputs)
+
+        expect(setFailedMock).toHaveBeenCalledWith(
+          new Error(
+            'predicate-type is required when using predicate or predicate-path'
+          )
+        )
+      })
+    })
+
+    describe('when custom attestation inputs are provided', () => {
+      const inputs: RunInputs = {
+        ...defaultInputs,
+        subjectDigest,
+        subjectName,
+        predicateType,
+        predicate,
+        githubToken: 'gh-token'
+      }
+
+      beforeEach(async () => {
+        setGHContext({
+          payload: { repository: { visibility: 'private' } },
+          repo: { owner: 'foo', repo: 'bar' }
+        })
+
+        await mockFulcio({
+          baseURL: 'https://fulcio.githubapp.com',
+          strict: false
+        })
+        await mockTSA({ baseURL: 'https://timestamp.githubapp.com' })
+      })
+
+      it('logs the attestation type as Custom', async () => {
+        await run(inputs)
+
+        expect(setFailedMock).not.toHaveBeenCalled()
+        expect(infoMock).toHaveBeenCalledWith('Attestation type: Custom')
+      })
+    })
+
+    describe('when provenance attestation is detected', () => {
+      const inputs: RunInputs = {
+        ...defaultInputs,
+        subjectDigest,
+        subjectName,
+        githubToken: 'gh-token'
+      }
+
+      const mockProvPredicate = {
+        type: 'https://slsa.dev/provenance/v1',
+        params: { buildDefinition: {}, runDetails: {} }
+      }
+
+      beforeEach(async () => {
+        // Configure mock for provenance predicate
+        generateProvenancePredicateMock.mockResolvedValue(mockProvPredicate)
+
+        // Configure mock for createAttestation
+        createAttestationMock.mockResolvedValue({
+          attestationID: '1234567890',
+          certificate:
+            '-----BEGIN CERTIFICATE-----\ntest\n-----END CERTIFICATE-----',
+          tlogID: 'tlog-123',
+          attestationDigest: 'sha256:123456',
+          bundle: { mediaType: 'application/vnd.dev.sigstore.bundle.v0.3+json' }
+        })
+
+        setGHContext({
+          payload: { repository: { visibility: 'private' } },
+          repo: { owner: 'foo', repo: 'bar' }
+        })
+
+        await mockFulcio({
+          baseURL: 'https://fulcio.githubapp.com',
+          strict: false
+        })
+        await mockTSA({ baseURL: 'https://timestamp.githubapp.com' })
+      })
+
+      it('logs the attestation type as Build Provenance and generates predicate', async () => {
+        await run(inputs)
+
+        expect(setFailedMock).not.toHaveBeenCalled()
+        expect(infoMock).toHaveBeenCalledWith(
+          'Attestation type: Build Provenance'
+        )
+      })
+    })
+
+    describe('when sbom attestation is detected', () => {
+      let tmpDir: string
+      let sbomFilePath: string
+
+      const spdxSBOM = {
+        spdxVersion: 'SPDX-2.3',
+        SPDXID: 'SPDXRef-DOCUMENT',
+        name: 'test-package',
+        packages: []
+      }
+
+      beforeEach(async () => {
+        tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), 'main-test-'))
+        sbomFilePath = path.join(tmpDir, 'sbom.spdx.json')
+        await fs.writeFile(sbomFilePath, JSON.stringify(spdxSBOM))
+
+        setGHContext({
+          payload: { repository: { visibility: 'private' } },
+          repo: { owner: 'foo', repo: 'bar' }
+        })
+
+        await mockFulcio({
+          baseURL: 'https://fulcio.githubapp.com',
+          strict: false
+        })
+        await mockTSA({ baseURL: 'https://timestamp.githubapp.com' })
+      })
+
+      afterEach(async () => {
+        await fs.rm(tmpDir, { recursive: true })
+      })
+
+      it('logs the attestation type as SBOM and generates predicate', async () => {
+        const inputs: RunInputs = {
+          ...defaultInputs,
+          subjectDigest,
+          subjectName,
+          sbomPath: sbomFilePath,
+          githubToken: 'gh-token'
+        }
+
+        await run(inputs)
+
+        expect(setFailedMock).not.toHaveBeenCalled()
+        expect(infoMock).toHaveBeenCalledWith('Attestation type: SBOM')
+      })
+    })
+  })
 })

-// Stubbing the GitHub context is a bit tricky. We need to use
-// `Object.defineProperty` because `github.context` is read-only.
-function setGHContext(context: object): void {
-  Object.defineProperty(github, 'context', { value: context })
+// Helper to update the mock context
+function setGHContext(context: {
+  repo?: { owner: string; repo: string }
+  payload?: { repository?: { visibility: string } }
+}): void {
+  if (context.repo) {
+    mockContext.repo = context.repo
+  }
+  if (context.payload) {
+    mockContext.payload = context.payload as typeof mockContext.payload
+  }
 }
@@ -11,33 +11,35 @@ describe('subjectFromInputs', () => {
  }

  describe('when no inputs are provided', () => {
-    it('throws an error', () => {
-      expect(() => predicateFromInputs(blankInputs)).toThrow(/predicate-type/i)
+    it('throws an error', async () => {
+      await expect(predicateFromInputs(blankInputs)).rejects.toThrow(
+        /predicate-type/i
+      )
    })
  })

  describe('when neither predicate path nor predicate are provided', () => {
-    it('throws an error', () => {
+    it('throws an error', async () => {
      const inputs: PredicateInputs = {
        ...blankInputs,
        predicateType: 'https://example.com/predicate'
      }

-      expect(() => predicateFromInputs(inputs)).toThrow(
+      await expect(predicateFromInputs(inputs)).rejects.toThrow(
        /one of predicate-path or predicate must be provided/i
      )
    })
  })

  describe('when both predicate path and predicate are provided', () => {
-    it('throws an error', () => {
+    it('throws an error', async () => {
      const inputs: PredicateInputs = {
        predicateType: 'https://example.com/predicate',
        predicate: '{}',
        predicatePath: 'path/to/predicate'
      }

-      expect(() => predicateFromInputs(inputs)).toThrow(
+      await expect(predicateFromInputs(inputs)).rejects.toThrow(
        /only one of predicate-path or predicate may be provided/i
      )
    })
@@ -65,13 +67,13 @@ describe('subjectFromInputs', () => {
      await fs.rm(path.parse(predicatePath).dir, { recursive: true })
    })

-    it('returns the predicate', () => {
+    it('returns the predicate', async () => {
      const inputs: PredicateInputs = {
        ...blankInputs,
        predicateType,
        predicatePath
      }
-      expect(predicateFromInputs(inputs)).toEqual({
+      await expect(predicateFromInputs(inputs)).resolves.toEqual({
        type: predicateType,
        params: JSON.parse(content)
      })
@@ -82,13 +84,15 @@ describe('subjectFromInputs', () => {
    const predicateType = 'https://example.com/predicate'
    const predicatePath = 'foo'

-    it('returns the predicate', () => {
+    it('returns the predicate', async () => {
      const inputs: PredicateInputs = {
        ...blankInputs,
        predicateType,
        predicatePath
      }
-      expect(() => predicateFromInputs(inputs)).toThrow(/file not found/)
+      await expect(predicateFromInputs(inputs)).rejects.toThrow(
+        /file not found/
+      )
    })
  })

@@ -96,14 +100,14 @@ describe('subjectFromInputs', () => {
    const predicateType = 'https://example.com/predicate'
    const content = '{}'

-    it('returns the predicate', () => {
+    it('returns the predicate', async () => {
      const inputs: PredicateInputs = {
        ...blankInputs,
        predicateType,
        predicate: content
      }

-      expect(predicateFromInputs(inputs)).toEqual({
+      await expect(predicateFromInputs(inputs)).resolves.toEqual({
        type: predicateType,
        params: JSON.parse(content)
      })
@@ -114,14 +118,14 @@ describe('subjectFromInputs', () => {
    const predicateType = 'https://example.com/predicate'
    const content = JSON.stringify({ a: 'a'.repeat(16 * 1024 * 1024) })

-    it('throws an error', () => {
+    it('throws an error', async () => {
      const inputs: PredicateInputs = {
        ...blankInputs,
        predicateType,
        predicate: content
      }

-      expect(() => predicateFromInputs(inputs)).toThrow(
+      await expect(predicateFromInputs(inputs)).rejects.toThrow(
        /predicate string exceeds maximum/
      )
    })
@@ -0,0 +1,48 @@
+import type { Predicate } from '@actions/attest'
+import { jest } from '@jest/globals'
+
+// Mock function
+const mockBuildSLSAProvenancePredicate = jest.fn<() => Promise<Predicate>>()
+
+// Mock @actions/attest
+jest.unstable_mockModule('@actions/attest', () => ({
+  buildSLSAProvenancePredicate: mockBuildSLSAProvenancePredicate
+}))
+
+// Dynamic import after mocking
+const { generateProvenancePredicate } = await import('../src/provenance')
+
+describe('generateProvenancePredicate', () => {
+  const mockPredicate = {
+    type: 'https://slsa.dev/provenance/v1',
+    params: {
+      buildDefinition: {
+        buildType: 'https://actions.github.io/buildtypes/workflow/v1'
+      },
+      runDetails: {
+        builder: { id: 'https://github.com/actions/runner' }
+      }
+    }
+  }
+
+  beforeEach(() => {
+    jest.clearAllMocks()
+    mockBuildSLSAProvenancePredicate.mockResolvedValue(mockPredicate)
+  })
+
+  it('returns the SLSA provenance predicate', async () => {
+    const result = await generateProvenancePredicate()
+
+    expect(mockBuildSLSAProvenancePredicate).toHaveBeenCalledTimes(1)
+    expect(result).toEqual(mockPredicate)
+  })
+
+  it('propagates errors from buildSLSAProvenancePredicate', async () => {
+    const error = new Error('Failed to build provenance')
+    mockBuildSLSAProvenancePredicate.mockRejectedValue(error)
+
+    await expect(generateProvenancePredicate()).rejects.toThrow(
+      'Failed to build provenance'
+    )
+  })
+})
@@ -0,0 +1,161 @@
+import fs from 'fs/promises'
+import os from 'os'
+import path from 'path'
+import { parseSBOMFromPath, generateSBOMPredicate, SBOM } from '../src/sbom'
+
+describe('parseSBOMFromPath', () => {
+  let tmpDir: string
+
+  beforeEach(async () => {
+    tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), 'sbom-test-'))
+  })
+
+  afterEach(async () => {
+    await fs.rm(tmpDir, { recursive: true })
+  })
+
+  describe('when file does not exist', () => {
+    it('throws an error', async () => {
+      await expect(parseSBOMFromPath('/nonexistent/file.json')).rejects.toThrow(
+        /ENOENT/
+      )
+    })
+  })
+
+  describe('when file contains valid SPDX SBOM', () => {
+    const spdxSBOM = {
+      spdxVersion: 'SPDX-2.3',
+      SPDXID: 'SPDXRef-DOCUMENT',
+      name: 'test-package',
+      packages: []
+    }
+
+    it('returns SBOM with type spdx', async () => {
+      const filePath = path.join(tmpDir, 'sbom.spdx.json')
+      await fs.writeFile(filePath, JSON.stringify(spdxSBOM))
+
+      const result = await parseSBOMFromPath(filePath)
+
+      expect(result.type).toBe('spdx')
+      expect(result.object).toEqual(spdxSBOM)
+    })
+  })
+
+  describe('when file contains valid CycloneDX SBOM', () => {
+    const cyclonedxSBOM = {
+      bomFormat: 'CycloneDX',
+      specVersion: '1.4',
+      serialNumber: 'urn:uuid:12345',
+      components: []
+    }
+
+    it('returns SBOM with type cyclonedx', async () => {
+      const filePath = path.join(tmpDir, 'sbom.cdx.json')
+      await fs.writeFile(filePath, JSON.stringify(cyclonedxSBOM))
+
+      const result = await parseSBOMFromPath(filePath)
+
+      expect(result.type).toBe('cyclonedx')
+      expect(result.object).toEqual(cyclonedxSBOM)
+    })
+  })
+
+  describe('when file contains invalid SBOM format', () => {
+    it('throws an error', async () => {
+      const filePath = path.join(tmpDir, 'invalid.json')
+      await fs.writeFile(filePath, JSON.stringify({ random: 'data' }))
+
+      await expect(parseSBOMFromPath(filePath)).rejects.toThrow(
+        /Unsupported SBOM format/
+      )
+    })
+  })
+
+  describe('when file contains invalid JSON', () => {
+    it('throws an error', async () => {
+      const filePath = path.join(tmpDir, 'invalid.json')
+      await fs.writeFile(filePath, 'not valid json')
+
+      await expect(parseSBOMFromPath(filePath)).rejects.toThrow()
+    })
+  })
+
+  describe('when file exceeds maximum size', () => {
+    it('throws an error', async () => {
+      const filePath = path.join(tmpDir, 'large.json')
+      // Create a file larger than 16MB
+      const largeContent = 'x'.repeat(17 * 1024 * 1024)
+      await fs.writeFile(filePath, largeContent)
+
+      await expect(parseSBOMFromPath(filePath)).rejects.toThrow(
+        /SBOM file exceeds maximum allowed size/
+      )
+    })
+  })
+})
+
+describe('generateSBOMPredicate', () => {
+  describe('for SPDX SBOM', () => {
+    const spdxSBOM: SBOM = {
+      type: 'spdx',
+      object: {
+        spdxVersion: 'SPDX-2.3',
+        SPDXID: 'SPDXRef-DOCUMENT',
+        name: 'test-package'
+      }
+    }
+
+    it('returns predicate with correct SPDX type', () => {
+      const predicate = generateSBOMPredicate(spdxSBOM)
+
+      expect(predicate.type).toBe('https://spdx.dev/Document/v2.3')
+      expect(predicate.params).toEqual(spdxSBOM.object)
+    })
+  })
+
+  describe('for CycloneDX SBOM', () => {
+    const cyclonedxSBOM: SBOM = {
+      type: 'cyclonedx',
+      object: {
+        bomFormat: 'CycloneDX',
+        specVersion: '1.4',
+        serialNumber: 'urn:uuid:12345'
+      }
+    }
+
+    it('returns predicate with correct CycloneDX type', () => {
+      const predicate = generateSBOMPredicate(cyclonedxSBOM)
+
+      expect(predicate.type).toBe('https://cyclonedx.org/bom')
+      expect(predicate.params).toEqual(cyclonedxSBOM.object)
+    })
+  })
+
+  describe('for SPDX without version', () => {
+    const invalidSBOM: SBOM = {
+      type: 'spdx',
+      object: {
+        SPDXID: 'SPDXRef-DOCUMENT'
+      }
+    }
+
+    it('throws an error', () => {
+      expect(() => generateSBOMPredicate(invalidSBOM)).toThrow(
+        /Cannot find spdxVersion/
+      )
+    })
+  })
+
+  describe('for unsupported SBOM type', () => {
+    const unsupportedSBOM = {
+      type: 'unknown' as SBOM['type'],
+      object: { foo: 'bar' }
+    }
+
+    it('throws an error', () => {
+      expect(() => generateSBOMPredicate(unsupportedSBOM)).toThrow(
+        /Unsupported SBOM format/
+      )
+    })
+  })
+})
@@ -12,13 +12,14 @@ describe('subjectFromInputs', () => {
  const blankInputs: SubjectInputs = {
    subjectPath: '',
    subjectName: '',
-    subjectDigest: ''
+    subjectDigest: '',
+    subjectChecksums: ''
  }

  describe('when no inputs are provided', () => {
    it('throws an error', async () => {
      await expect(subjectFromInputs(blankInputs)).rejects.toThrow(
-        /one of subject-path or subject-digest must be provided/i
+        /one of subject-path, subject-digest, or subject-checksums must be provided/i
      )
    })
  })
@@ -28,11 +29,42 @@ describe('subjectFromInputs', () => {
      const inputs: SubjectInputs = {
        subjectName: 'foo',
        subjectPath: 'path/to/subject',
-        subjectDigest: 'digest'
+        subjectDigest: 'digest',
+        subjectChecksums: ''
      }

      await expect(subjectFromInputs(inputs)).rejects.toThrow(
-        /only one of subject-path or subject-digest may be provided/i
+        /only one of subject-path, subject-digest, or subject-checksums may be provided/i
+      )
+    })
+  })
+
+  describe('when both subject path and subject checksums are provided', () => {
+    it('throws an error', async () => {
+      const inputs: SubjectInputs = {
+        subjectName: '',
+        subjectPath: 'path/to/subject',
+        subjectDigest: '',
+        subjectChecksums: 'path/to/checksums'
+      }
+
+      await expect(subjectFromInputs(inputs)).rejects.toThrow(
+        /only one of subject-path, subject-digest, or subject-checksums may be provided/i
+      )
+    })
+  })
+
+  describe('when both subject digest and subject checksums are provided', () => {
+    it('throws an error', async () => {
+      const inputs: SubjectInputs = {
+        subjectName: 'foo',
+        subjectPath: '',
+        subjectDigest: 'digest',
+        subjectChecksums: 'path/to/checksums'
+      }
+
+      await expect(subjectFromInputs(inputs)).rejects.toThrow(
+        /only one of subject-path, subject-digest, or subject-checksums may be provided/i
      )
    })
  })
@@ -67,7 +99,7 @@ describe('subjectFromInputs', () => {
      })
    })

-    describe('when the alogrithm is not supported', () => {
+    describe('when the algorithm is not supported', () => {
      it('throws an error', async () => {
        const inputs: SubjectInputs = {
          ...blankInputs,
@@ -232,7 +264,6 @@ describe('subjectFromInputs', () => {
        expect(subjects).toBeDefined()
        expect(subjects).toHaveLength(3)

-        /* eslint-disable-next-line github/array-foreach */
        subjects.forEach((subject, i) => {
          expect(subject.name).toEqual(`${filename}-${i}`)
          expect(subject.digest).toEqual({ sha256: expectedDigest })
@@ -362,6 +393,197 @@ describe('subjectFromInputs', () => {
        })
      })
    })
+
+    describe('when duplicate subjects are supplied', () => {
+      let otherDir = ''
+
+      // Add duplicate subject in alternate directory
+      beforeEach(async () => {
+        // Set-up temp directory
+        const tmpDir = await fs.realpath(os.tmpdir())
+        otherDir = await fs.mkdtemp(tmpDir + path.sep)
+
+        // Write file to temp directory
+        await fs.writeFile(path.join(otherDir, filename), content)
+      })
+
+      it('returns de-duplicated subjects', async () => {
+        const inputs: SubjectInputs = {
+          ...blankInputs,
+          subjectPath: `${path.join(dir, 'subject')}, ${path.join(otherDir, 'subject')} `
+        }
+        const subjects = await subjectFromInputs(inputs)
+
+        expect(subjects).toBeDefined()
+        expect(subjects).toHaveLength(1)
+      })
+    })
+  })
+
+  describe('when specifying a subject checksums file', () => {
+    const checksums = `
+187dcd1506a170337415589ff00c8743f19d41cc31fca246c2739dfd450d0b9d  demo_0.0.1_linux_amd64
+badline
+5d8b4751ef31f9440d843fcfa4e53ca2e25b1cb1f13fd355fdc7c24b41fe645293291ea9297ba3989078abb77ebbaac66be073618a9e4974dbd0361881d4c718 demo_0.0.1_darwin_arm64`
+
+    let dir = ''
+    const filename = 'checksums'
+
+    beforeEach(async () => {
+      // Set-up temp directory
+      const tmpDir = await fs.realpath(os.tmpdir())
+      dir = await fs.mkdtemp(tmpDir + path.sep)
+
+      // Write file to temp directory
+      await fs.writeFile(path.join(dir, filename), checksums)
+    })
+
+    afterEach(async () => {
+      // Clean-up temp directory
+      await fs.rm(dir, { recursive: true })
+    })
+
+    describe('when the specified path is NOT a file', () => {
+      it('throws an error', async () => {
+        const inputs: SubjectInputs = {
+          ...blankInputs,
+          subjectChecksums: dir
+        }
+        await expect(subjectFromInputs(inputs)).rejects.toThrow(
+          /subject checksums file not found/i
+        )
+      })
+    })
+
+    describe('when the specific path is a file', () => {
+      it('returns the multiple subjects', async () => {
+        const inputs: SubjectInputs = {
+          ...blankInputs,
+          subjectChecksums: path.join(dir, filename)
+        }
+        const subjects = await subjectFromInputs(inputs)
+
+        expect(subjects).toBeDefined()
+        expect(subjects).toHaveLength(2)
+
+        expect(subjects).toContainEqual({
+          name: 'demo_0.0.1_linux_amd64',
+          digest: {
+            sha256:
+              '187dcd1506a170337415589ff00c8743f19d41cc31fca246c2739dfd450d0b9d'
+          }
+        })
+        expect(subjects).toContainEqual({
+          name: 'demo_0.0.1_darwin_arm64',
+          digest: {
+            sha512:
+              '5d8b4751ef31f9440d843fcfa4e53ca2e25b1cb1f13fd355fdc7c24b41fe645293291ea9297ba3989078abb77ebbaac66be073618a9e4974dbd0361881d4c718'
+          }
+        })
+      })
+    })
+  })
+
+  describe('when specifying a subject checksums string', () => {
+    const checksums = `
+f861e68a080799ca83104630b56abb90d8dbcc5f8b5a8639cb691e269838f29e  demo_0.0.1_linux_386
+187dcd1506a170337415589ff00c8743f19d41cc31fca246c2739dfd450d0b9d *demo_0.0.1_linux_amd64
+9ecbf449e286a8a8748c161c52aa28b6b2fc64ab86f94161c5d1b3abc18156c5 demo_0.0.1_linux_arm64`
+
+    it('returns the multiple subjects', async () => {
+      const inputs: SubjectInputs = {
+        ...blankInputs,
+        subjectChecksums: checksums
+      }
+      const subjects = await subjectFromInputs(inputs)
+
+      expect(subjects).toBeDefined()
+      expect(subjects).toHaveLength(3)
+
+      expect(subjects).toContainEqual({
+        name: 'demo_0.0.1_linux_386',
+        digest: {
+          sha256:
+            'f861e68a080799ca83104630b56abb90d8dbcc5f8b5a8639cb691e269838f29e'
+        }
+      })
+      expect(subjects).toContainEqual({
+        name: 'demo_0.0.1_linux_amd64',
+        digest: {
+          sha256:
+            '187dcd1506a170337415589ff00c8743f19d41cc31fca246c2739dfd450d0b9d'
+        }
+      })
+      expect(subjects).toContainEqual({
+        name: 'demo_0.0.1_linux_arm64',
+        digest: {
+          sha256:
+            '9ecbf449e286a8a8748c161c52aa28b6b2fc64ab86f94161c5d1b3abc18156c5'
+        }
+      })
+    })
+  })
+
+  describe('when specifying a subject checksums string with duplicates', () => {
+    const checksums = `
+f861e68a080799ca83104630b56abb90d8dbcc5f8b5a8639cb691e269838f29e  demo_0.0.1_linux_386
+f861e68a080799ca83104630b56abb90d8dbcc5f8b5a8639cb691e269838f29e  demo_0.0.1_linux_386
+187dcd1506a170337415589ff00c8743f19d41cc31fca246c2739dfd450d0b9d *demo_0.0.1_linux_amd64`
+
+    it('returns de-duplicated subjects', async () => {
+      const inputs: SubjectInputs = {
+        ...blankInputs,
+        subjectChecksums: checksums
+      }
+      const subjects = await subjectFromInputs(inputs)
+
+      expect(subjects).toBeDefined()
+      expect(subjects).toHaveLength(2)
+
+      expect(subjects).toContainEqual({
+        name: 'demo_0.0.1_linux_386',
+        digest: {
+          sha256:
+            'f861e68a080799ca83104630b56abb90d8dbcc5f8b5a8639cb691e269838f29e'
+        }
+      })
+      expect(subjects).toContainEqual({
+        name: 'demo_0.0.1_linux_amd64',
+        digest: {
+          sha256:
+            '187dcd1506a170337415589ff00c8743f19d41cc31fca246c2739dfd450d0b9d'
+        }
+      })
+    })
+  })
+
+  describe('when specifying a subject checksums string with an unrecognized digest', () => {
+    const checksums = `f861e  demo_0.0.1_linux_386`
+
+    it('throws an error', async () => {
+      const inputs: SubjectInputs = {
+        ...blankInputs,
+        subjectChecksums: checksums
+      }
+
+      await expect(subjectFromInputs(inputs)).rejects.toThrow(
+        /unknown digest algorithm/i
+      )
+    })
+  })
+
+  describe('when specifying a subject checksums string with an invalid digest', () => {
+    const checksums =
+      '!!!!e68a080799ca83104630b56abb90d8dbcc5f8b5a8639cb691e269838f29e  demo_0.0.1_linux_386'
+
+    it('throws an error', async () => {
+      const inputs: SubjectInputs = {
+        ...blankInputs,
+        subjectChecksums: checksums
+      }
+
+      await expect(subjectFromInputs(inputs)).rejects.toThrow(/invalid digest/i)
+    })
  })
 })

@@ -9,36 +9,50 @@ inputs:
  subject-path:
    description: >
      Path to the artifact serving as the subject of the attestation. Must
-      specify exactly one of "subject-path" or "subject-digest". May contain a
-      glob pattern or list of paths (total subject count cannot exceed 1024).
+      specify exactly one of "subject-path",  "subject-digest", or
+      "subject-checksums". May contain a glob pattern or list of paths (total
+      subject count cannot exceed 1024).
    required: false
  subject-digest:
    description: >
      Digest of the subject for the attestation. Must be in the form
      "algorithm:hex_digest" (e.g. "sha256:abc123..."). Must specify exactly one
-      of "subject-path" or "subject-digest".
+      of "subject-path", "subject-digest", or "subject-checksums".
    required: false
  subject-name:
    description: >
-      Subject name as it should appear in the attestation. Required unless
-      "subject-path" is specified, in which case it will be inferred from the
-      path.
+      Subject name as it should appear in the attestation. Required when
+      identifying the subject with the "subject-digest" input.
+    required: false
+  subject-checksums:
+    description: >
+      Path to checksums file containing digest and name of subjects for
+      attestation. Must specify exactly one of "subject-path", "subject-digest",
+      or "subject-checksums".
+    required: false
+  sbom-path:
+    description: >
+      Path to the JSON-formatted SBOM file (SPDX or CycloneDX) to attest.
+      File size cannot exceed 16MB. When provided, creates an SBOM attestation.
+      Cannot be used together with "predicate-type", "predicate", or
+      "predicate-path".
    required: false
  predicate-type:
    description: >
-      URI identifying the type of the predicate.
-    required: true
+      URI identifying the type of the predicate. Required when using "predicate"
+      or "predicate-path" for custom attestations.
+    required: false
  predicate:
    description: >
      String containing the value for the attestation predicate. String length
      cannot exceed 16MB. Must supply exactly one of "predicate-path" or
-      "predicate".
+      "predicate" when creating custom attestations.
    required: false
  predicate-path:
    description: >
      Path to the file which contains the content for the attestation predicate.
      File size cannot exceed 16MB. Must supply exactly one of "predicate-path"
-      or "predicate".
+      or "predicate" when creating custom attestations.
    required: false
  push-to-registry:
    description: >
@@ -47,6 +61,12 @@ inputs:
      the "subject-digest" parameter be specified. Defaults to false.
    default: false
    required: false
+  create-storage-record:
+    description: >
+      Whether to create a storage record for the artifact.
+      Requires that push-to-registry is set to true. Defaults to true.
+    default: true
+    required: false
  show-summary:
    description: >
      Whether to attach a list of generated attestations to the workflow run
@@ -61,7 +81,13 @@ inputs:
 outputs:
  bundle-path:
    description: 'The path to the file containing the attestation bundle.'
+  attestation-id:
+    description: 'The ID of the attestation.'
+  attestation-url:
+    description: 'The URL for the attestation summary.'
+  storage-record-ids:
+    description: 'The IDs of the storage records created for the artifact.'

 runs:
-  using: node20
+  using: node24
  main: ./dist/index.js
@@ -1,7 +1,6 @@
-"use strict";
-exports.id = 606;
-exports.ids = [606];
-exports.modules = {
+export const id = 606;
+export const ids = [606];
+export const modules = {

 /***/ 606:
 /***/ ((__unused_webpack___webpack_module__, __webpack_exports__, __webpack_require__) => {
@@ -19,7 +18,7 @@ async function pMap(
 		signal,
 	} = {},
 ) {
-	return new Promise((resolve, reject_) => {
+	return new Promise((resolve_, reject_) => {
 		if (iterable[Symbol.iterator] === undefined && iterable[Symbol.asyncIterator] === undefined) {
 			throw new TypeError(`Expected \`input\` to be either an \`Iterable\` or \`AsyncIterable\`, got (${typeof iterable})`);
 		}
@@ -42,10 +41,24 @@ async function pMap(
 		let currentIndex = 0;
 		const iterator = iterable[Symbol.iterator] === undefined ? iterable[Symbol.asyncIterator]() : iterable[Symbol.iterator]();

+		const signalListener = () => {
+			reject(signal.reason);
+		};
+
+		const cleanup = () => {
+			signal?.removeEventListener('abort', signalListener);
+		};
+
+		const resolve = value => {
+			resolve_(value);
+			cleanup();
+		};
+
 		const reject = reason => {
 			isRejected = true;
 			isResolved = true;
 			reject_(reason);
+			cleanup();
 		};

 		if (signal) {
@@ -53,9 +66,7 @@ async function pMap(
 				reject(signal.reason);
 			}

-			signal.addEventListener('abort', () => {
-				reject(signal.reason);
-			});
+			signal.addEventListener('abort', signalListener, {once: true});
 		}

 		const next = async () => {
@@ -203,31 +214,32 @@ function pMapIterable(
 			const iterator = iterable[Symbol.asyncIterator] === undefined ? iterable[Symbol.iterator]() : iterable[Symbol.asyncIterator]();

 			const promises = [];
-			let runningMappersCount = 0;
+			let pendingPromisesCount = 0;
 			let isDone = false;
 			let index = 0;

 			function trySpawn() {
-				if (isDone || !(runningMappersCount < concurrency && promises.length < backpressure)) {
+				if (isDone || !(pendingPromisesCount < concurrency && promises.length < backpressure)) {
 					return;
 				}

+				pendingPromisesCount++;
+
 				const promise = (async () => {
 					const {done, value} = await iterator.next();

 					if (done) {
+						pendingPromisesCount--;
 						return {done: true};
 					}

-					runningMappersCount++;
-
 					// Spawn if still below concurrency and backpressure limit
 					trySpawn();

 					try {
 						const returnValue = await mapper(await value, index++);

-						runningMappersCount--;
+						pendingPromisesCount--;

 						if (returnValue === pMapSkip) {
 							const index = promises.indexOf(promise);
@@ -242,6 +254,7 @@ function pMapIterable(

 						return {done: false, value: returnValue};
 					} catch (error) {
+						pendingPromisesCount--;
 						isDone = true;
 						return {error};
 					}
@@ -284,4 +297,3 @@ const pMapSkip = Symbol('skip');
 /***/ })

 };
-;
@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}
@@ -0,0 +1,94 @@
+import eslint from '@eslint/js'
+import importplugin from 'eslint-plugin-import'
+import jestplugin from 'eslint-plugin-jest'
+import path from 'node:path'
+import tseslint from 'typescript-eslint'
+
+export default tseslint.config(
+  // Ignore non-project files
+  {
+    name: 'ignore',
+    ignores: ['.github', 'dist', 'coverage', '**/*.json', 'jest.setup.js', 'eslint.config.mjs']
+  },
+  // Use recommended rules from ESLint, TypeScript, and other plugins
+  eslint.configs.recommended,
+  tseslint.configs.recommendedTypeChecked,
+  jestplugin.configs['flat/recommended'],
+  importplugin.flatConfigs.recommended,
+  importplugin.flatConfigs.typescript,
+  // Override some rules
+  {
+    name: 'project-settings',
+    languageOptions: {
+      ecmaVersion: 2023,
+      parserOptions: {
+        project: [ './tsconfig.lint.json' ]
+      }
+    },
+    rules: {
+      // eslint rules
+      eqeqeq: ['error', 'smart'],
+      'func-style': ['error', 'declaration', { allowArrowFunctions: true }],
+      'no-console': 'off',
+      'no-implicit-globals': 'error',
+      'no-inner-declarations': 'error',
+      'no-invalid-this': 'error',
+      'no-return-assign': 'error',
+      'no-sequences': 'error',
+      'no-shadow': 'error',
+      'no-useless-concat': 'error',
+      'object-shorthand': ['error', 'always', { avoidQuotes: true }],
+      'one-var': ['error', 'never'],
+      'prefer-template': 'error',
+
+      // typescript-eslint rules
+      '@typescript-eslint/array-type': 'error',
+      '@typescript-eslint/consistent-type-assertions': 'error',
+      '@typescript-eslint/explicit-function-return-type': [
+        'error',
+        { allowExpressions: true }
+      ],
+      '@typescript-eslint/explicit-member-accessibility': [
+        'error',
+        { accessibility: 'no-public' }
+      ],
+      '@typescript-eslint/no-extraneous-class': 'error',
+      '@typescript-eslint/no-inferrable-types': 'error',
+      '@typescript-eslint/no-non-null-assertion': 'warn',
+      '@typescript-eslint/no-unnecessary-qualifier': 'error',
+      '@typescript-eslint/no-unsafe-argument': 'off',
+      '@typescript-eslint/no-unsafe-assignment': 'off',
+      '@typescript-eslint/no-useless-constructor': 'error',
+      '@typescript-eslint/prefer-for-of': 'warn',
+      '@typescript-eslint/prefer-function-type': 'warn',
+      '@typescript-eslint/prefer-includes': 'error',
+      '@typescript-eslint/prefer-string-starts-ends-with': 'error',
+      '@typescript-eslint/promise-function-async': 'error',
+      '@typescript-eslint/require-array-sort-compare': 'error',
+      '@typescript-eslint/restrict-template-expressions': 'off',
+
+      // eslint-plugin-import rules
+      'import/extensions': 'error',
+      'import/first': 'error',
+      'import/no-absolute-path': 'error',
+      'import/no-commonjs': 'error',
+      'import/no-deprecated': 'warn',
+      'import/no-dynamic-require': 'error',
+      'import/no-extraneous-dependencies': 'error',
+      'import/no-mutable-exports': 'error',
+      'import/no-namespace': 'off',
+      'import/no-unresolved': ['error', { ignore: ['csv-parse/sync'] }],
+      'import/no-anonymous-default-export': [
+        'error',
+        {
+          allowAnonymousClass: false,
+          allowAnonymousFunction: false,
+          allowArray: true,
+          allowArrowFunction: false,
+          allowLiteral: true,
+          allowObject: true
+        }
+      ]
+    }
+  }
+)
@@ -1 +1,3 @@
+import { jest } from '@jest/globals'
+
 process.stdout.write = jest.fn()
@@ -1,9 +1,10 @@
 {
  "name": "actions/attest",
  "description": "Generate signed attestations for workflow artifacts",
-  "version": "2.0.0",
+  "version": "3.2.0",
  "author": "",
  "private": true,
+  "type": "module",
  "homepage": "https://github.com/actions/attest",
  "repository": {
    "type": "git",
@@ -20,24 +21,27 @@
    ".": "./dist/index.js"
  },
  "engines": {
-    "node": ">=20"
+    "node": ">=24"
  },
  "scripts": {
    "bundle": "npm run format:write && npm run package",
-    "ci-test": "jest",
+    "ci-test": "NODE_OPTIONS='--experimental-vm-modules' jest",
    "format:write": "prettier --write **/*.ts",
    "format:check": "prettier --check **/*.ts",
-    "lint:eslint": "npx eslint . -c ./.github/linters/.eslintrc.yml",
-    "lint:markdown": "npx markdownlint --config .github/linters/.markdown-lint.yml \"*.md\"",
+    "lint:eslint": "npx eslint",
+    "lint:markdown": "npx markdownlint --config .markdown-lint.yml \"*.md\"",
    "lint": "npm run lint:eslint && npm run lint:markdown",
    "package": "ncc build src/index.ts --license licenses.txt",
    "package:watch": "npm run package -- --watch",
-    "test": "jest",
+    "test": "NODE_OPTIONS='--experimental-vm-modules' jest",
    "all": "npm run format:write && npm run lint && npm run test && npm run package"
  },
  "license": "MIT",
  "jest": {
-    "preset": "ts-jest",
+    "preset": "ts-jest/presets/default-esm",
+    "extensionsToTreatAsEsm": [
+      ".ts"
+    ],
    "setupFilesAfterEnv": [
      "./jest.setup.js"
    ],
@@ -56,7 +60,12 @@
      "/dist/"
    ],
    "transform": {
-      "^.+\\.ts$": "ts-jest"
+      "^.+\\.ts$": [
+        "ts-jest",
+        {
+          "useESM": true
+        }
+      ]
    },
    "coverageReporters": [
      "json-summary",
@@ -69,33 +78,32 @@
    ]
  },
  "dependencies": {
-    "@actions/attest": "^1.5.0",
-    "@actions/core": "^1.11.1",
-    "@actions/glob": "^0.5.0",
-    "@sigstore/oci": "^0.4.0",
+    "@actions/attest": "^3.0.0",
+    "@actions/core": "^3.0.0",
+    "@actions/github": "^9.0.0",
+    "@actions/glob": "^0.6.1",
+    "@sigstore/oci": "^0.6.0",
    "csv-parse": "^5.6.0"
  },
  "devDependencies": {
-    "@sigstore/mock": "^0.8.0",
-    "@types/jest": "^29.5.14",
+    "@eslint/js": "^9.39.2",
+    "@jest/globals": "^30.2.0",
+    "@sigstore/mock": "^0.11.0",
+    "@types/jest": "^30.0.0",
    "@types/make-fetch-happen": "^10.0.4",
-    "@types/node": "^22.9.4",
-    "@typescript-eslint/eslint-plugin": "^7.18.0",
-    "@typescript-eslint/parser": "^7.18.0",
-    "@vercel/ncc": "^0.38.3",
-    "eslint": "^8.57.1",
-    "eslint-plugin-github": "^5.1.2",
-    "eslint-plugin-jest": "^28.9.0",
-    "eslint-plugin-jsonc": "^2.18.2",
-    "eslint-plugin-prettier": "^5.2.1",
-    "jest": "^29.7.0",
-    "js-yaml": "^4.1.0",
-    "markdownlint-cli": "^0.43.0",
+    "@types/node": "^25.2.0",
+    "@vercel/ncc": "^0.38.4",
+    "eslint": "^9.39.2",
+    "eslint-plugin-import": "^2.32.0",
+    "eslint-plugin-jest": "^29.12.1",
+    "jest": "^30.2.0",
+    "js-yaml": "^4.1.1",
+    "markdownlint-cli": "^0.47.0",
    "nock": "^13.5.6",
-    "prettier": "^3.3.3",
-    "prettier-eslint": "^16.3.0",
-    "ts-jest": "^29.2.5",
-    "typescript": "^5.7.2",
-    "undici": "^5.28.4"
+    "prettier": "^3.8.1",
+    "ts-jest": "^29.4.6",
+    "typescript": "^5.9.3",
+    "typescript-eslint": "^8.54.0",
+    "undici": "^7.20.0"
  }
 }
@@ -1,4 +1,12 @@
-import { Attestation, Predicate, Subject, attest } from '@actions/attest'
+import {
+  Attestation,
+  Predicate,
+  Subject,
+  attest,
+  createStorageRecord
+} from '@actions/attest'
+import * as core from '@actions/core'
+import * as github from '@actions/github'
 import { attachArtifactToImage, getRegistryCredentials } from '@sigstore/oci'
 import { formatSubjectDigest } from './subject'

@@ -8,6 +16,7 @@ const OCI_RETRY = 3
 export type SigstoreInstance = 'public-good' | 'github'
 export type AttestResult = Attestation & {
  attestationDigest?: string
+  storageRecordIds?: number[]
 }

 export const createAttestation = async (
@@ -16,6 +25,7 @@ export const createAttestation = async (
  opts: {
    sigstoreInstance: SigstoreInstance
    pushToRegistry: boolean
+    createStorageRecord: boolean
    githubToken: string
  }
 ): Promise<AttestResult> => {
@@ -33,10 +43,11 @@ export const createAttestation = async (
  if (subjects.length === 1 && opts.pushToRegistry) {
    const subject = subjects[0]
    const credentials = getRegistryCredentials(subject.name)
+    const subjectDigest = formatSubjectDigest(subject)
    const artifact = await attachArtifactToImage({
      credentials,
      imageName: subject.name,
-      imageDigest: formatSubjectDigest(subject),
+      imageDigest: subjectDigest,
      artifact: Buffer.from(JSON.stringify(attestation.bundle)),
      mediaType: attestation.bundle.mediaType,
      annotations: {
@@ -48,7 +59,78 @@ export const createAttestation = async (

    // Add the attestation's digest to the result
    result.attestationDigest = artifact.digest
+
+    // Because creating a storage record requires the 'artifact-metadata:write'
+    // permission, we wrap this in a try/catch to avoid failing the entire
+    // attestation process if the token does not have the correct permissions.
+    if (opts.createStorageRecord) {
+      try {
+        const token = opts.githubToken
+        const isOrg = await repoOwnerIsOrg(token)
+        if (!isOrg) {
+          // The Artifact Metadata Storage Record API is only available to
+          // organizations. So if the repo owner is not an organization,
+          // storage record creation should not be attempted.
+          return result
+        }
+
+        const registryUrl = getRegistryURL(subject.name)
+        const artifactOpts = {
+          name: subject.name,
+          digest: subjectDigest
+        }
+        const packageRegistryOpts = {
+          registryUrl
+        }
+        const records = await createStorageRecord(
+          artifactOpts,
+          packageRegistryOpts,
+          token
+        )
+
+        if (!records || records.length === 0) {
+          core.warning('No storage records were created.')
+        }
+
+        result.storageRecordIds = records
+      } catch (error) {
+        core.warning(`Failed to create storage record: ${error}`)
+        core.warning(
+          'Please check that the "artifact-metadata:write" permission has been included'
+        )
+      }
+    }
  }

  return result
 }
+
+// Call the GET /repos/{owner}/{repo} endpoint to determine if the repo
+// owner is an organization. This is used to determine if storage
+// record creation should be attempted.
+export const repoOwnerIsOrg = async (githubToken: string): Promise<boolean> => {
+  const octokit = github.getOctokit(githubToken)
+  const { data: repo } = await octokit.rest.repos.get({
+    owner: github.context.repo.owner,
+    repo: github.context.repo.repo
+  })
+  return repo.owner?.type === 'Organization'
+}
+
+function getRegistryURL(subjectName: string): string {
+  let url: URL
+
+  try {
+    url = new URL(subjectName)
+  } catch {
+    url = new URL(`https://${subjectName}`)
+  }
+
+  if (url.protocol !== 'https:') {
+    throw new Error(
+      `Unsupported protocol ${url.protocol} in subject name ${subjectName}`
+    )
+  }
+
+  return url.origin
+}
@@ -0,0 +1,45 @@
+export type AttestationType = 'provenance' | 'sbom' | 'custom'
+
+export type DetectionInputs = {
+  sbomPath: string
+  predicateType: string
+  predicate: string
+  predicatePath: string
+}
+
+export const detectAttestationType = (
+  inputs: DetectionInputs
+): AttestationType => {
+  const { sbomPath, predicateType, predicate, predicatePath } = inputs
+
+  // SBOM mode takes priority
+  if (sbomPath) {
+    return 'sbom'
+  }
+
+  // Custom mode when any predicate inputs are provided
+  if (predicateType || predicate || predicatePath) {
+    return 'custom'
+  }
+
+  // Default to provenance mode
+  return 'provenance'
+}
+
+export const validateAttestationInputs = (inputs: DetectionInputs): void => {
+  const { sbomPath, predicateType, predicate, predicatePath } = inputs
+
+  // Cannot combine sbom-path with predicate inputs
+  if (sbomPath && (predicateType || predicate || predicatePath)) {
+    throw new Error(
+      'Cannot specify sbom-path together with predicate-type, predicate, or predicate-path'
+    )
+  }
+
+  // Custom mode requires predicate-type
+  if ((predicate || predicatePath) && !predicateType) {
+    throw new Error(
+      'predicate-type is required when using predicate or predicate-path'
+    )
+  }
+}
@@ -8,10 +8,13 @@ const inputs: RunInputs = {
  subjectPath: core.getInput('subject-path'),
  subjectName: core.getInput('subject-name'),
  subjectDigest: core.getInput('subject-digest'),
+  subjectChecksums: core.getInput('subject-checksums'),
+  sbomPath: core.getInput('sbom-path'),
  predicateType: core.getInput('predicate-type'),
  predicate: core.getInput('predicate'),
  predicatePath: core.getInput('predicate-path'),
  pushToRegistry: core.getBooleanInput('push-to-registry'),
+  createStorageRecord: core.getBooleanInput('create-storage-record'),
  showSummary: core.getBooleanInput('show-summary'),
  githubToken: core.getInput('github-token'),
  // undocumented -- not part of public interface
@@ -20,5 +23,5 @@ const inputs: RunInputs = {
  )
 }

-// eslint-disable-next-line @typescript-eslint/no-floating-promises
+/* eslint-disable-next-line @typescript-eslint/no-floating-promises */
 run(inputs)
@@ -1,11 +1,19 @@
 import * as core from '@actions/core'
 import * as github from '@actions/github'
-import fs from 'fs'
+import fs from 'fs/promises'
 import os from 'os'
 import path from 'path'
 import { AttestResult, SigstoreInstance, createAttestation } from './attest'
+import {
+  AttestationType,
+  DetectionInputs,
+  detectAttestationType,
+  validateAttestationInputs
+} from './detect'
 import { SEARCH_PUBLIC_GOOD_URL } from './endpoints'
 import { PredicateInputs, predicateFromInputs } from './predicate'
+import { generateProvenancePredicate } from './provenance'
+import { generateSBOMPredicate, parseSBOMFromPath } from './sbom'
 import * as style from './style'
 import {
  SubjectInputs,
@@ -13,13 +21,20 @@ import {
  subjectFromInputs
 } from './subject'

-import type { Subject } from '@actions/attest'
+import type { Predicate, Subject } from '@actions/attest'

 const ATTESTATION_FILE_NAME = 'attestation.json'
+const ATTESTATION_PATHS_FILE_NAME = 'created_attestation_paths.txt'
+
+export type SBOMInputs = {
+  sbomPath: string
+}

 export type RunInputs = SubjectInputs &
-  PredicateInputs & {
+  PredicateInputs &
+  SBOMInputs & {
    pushToRegistry: boolean
+    createStorageRecord: boolean
    githubToken: string
    showSummary: boolean
    privateSigning: boolean
@@ -56,31 +71,71 @@ export async function run(inputs: RunInputs): Promise<void> {
      )
    }

+    // Detect attestation type and validate inputs
+    const detectionInputs: DetectionInputs = {
+      sbomPath: inputs.sbomPath,
+      predicateType: inputs.predicateType,
+      predicate: inputs.predicate,
+      predicatePath: inputs.predicatePath
+    }
+    validateAttestationInputs(detectionInputs)
+    const attestationType = detectAttestationType(detectionInputs)
+    logAttestationType(attestationType)
+
    const subjects = await subjectFromInputs({
      ...inputs,
      downcaseName: inputs.pushToRegistry
    })
-    const predicate = predicateFromInputs(inputs)

-    const outputPath = path.join(tempDir(), ATTESTATION_FILE_NAME)
+    // Generate predicate based on attestation type
+    const predicate = await getPredicateForType(attestationType, inputs)
+
+    const outputPath = path.join(await tempDir(), ATTESTATION_FILE_NAME)
    core.setOutput('bundle-path', outputPath)

    const att = await createAttestation(subjects, predicate, {
      sigstoreInstance,
      pushToRegistry: inputs.pushToRegistry,
+      createStorageRecord: inputs.createStorageRecord,
      githubToken: inputs.githubToken
    })

    logAttestation(subjects, att, sigstoreInstance)

    // Write attestation bundle to output file
-    fs.writeFileSync(outputPath, JSON.stringify(att.bundle) + os.EOL, {
+    await fs.writeFile(outputPath, JSON.stringify(att.bundle) + os.EOL, {
      encoding: 'utf-8',
      flag: 'a'
    })

+    const baseDir = process.env.RUNNER_TEMP
+    /* istanbul ignore else */
+    if (baseDir) {
+      const outputSummaryPath = path.join(baseDir, ATTESTATION_PATHS_FILE_NAME)
+      // Append the output path to the attestations paths file
+      await fs.appendFile(outputSummaryPath, outputPath + os.EOL, {
+        encoding: 'utf-8',
+        flag: 'a'
+      })
+    } else {
+      core.warning(
+        'RUNNER_TEMP environment variable is not set. Cannot write attestation paths file.'
+      )
+    }
+
+    /* istanbul ignore else */
+    if (att.attestationID) {
+      core.setOutput('attestation-id', att.attestationID)
+      core.setOutput('attestation-url', attestationURL(att.attestationID))
+    }
+
+    if (att.storageRecordIds) {
+      core.setOutput('storage-record-ids', att.storageRecordIds.join(','))
+    }
+
+    /* istanbul ignore else */
    if (inputs.showSummary) {
-      logSummary(att)
+      await logSummary(att)
    }
  } catch (err) {
    // Fail the workflow run if an error occurs
@@ -136,6 +191,7 @@ const logAttestation = (
    core.info(`${SEARCH_PUBLIC_GOOD_URL}?logIndex=${attestation.tlogID}`)
  }

+  /* istanbul ignore else */
  if (attestation.attestationID) {
    core.info(style.highlight('Attestation uploaded to repository'))
    core.info(attestationURL(attestation.attestationID))
@@ -145,21 +201,27 @@ const logAttestation = (
    core.info(style.highlight('Attestation uploaded to registry'))
    core.info(`${subjects[0].name}@${attestation.attestationDigest}`)
  }
+
+  if (attestation.storageRecordIds && attestation.storageRecordIds.length > 0) {
+    core.info(style.highlight('Storage record created'))
+    core.info(`Storage record IDs: ${attestation.storageRecordIds.join(',')}`)
+  }
 }

 // Attach summary information to the GitHub Actions run
-const logSummary = (attestation: AttestResult): void => {
+const logSummary = async (attestation: AttestResult): Promise<void> => {
  const { attestationID } = attestation

+  /* istanbul ignore else */
  if (attestationID) {
    const url = attestationURL(attestationID)
    core.summary.addHeading('Attestation Created', 3)
    core.summary.addList([`<a href="${url}">${url}</a>`])
-    core.summary.write()
+    await core.summary.write()
  }
 }

-const tempDir = (): string => {
+const tempDir = async (): Promise<string> => {
  const basePath = process.env['RUNNER_TEMP']

  /* istanbul ignore if */
@@ -167,8 +229,35 @@ const tempDir = (): string => {
    throw new Error('Missing RUNNER_TEMP environment variable')
  }

-  return fs.mkdtempSync(path.join(basePath, path.sep))
+  return fs.mkdtemp(path.join(basePath, path.sep))
 }

 const attestationURL = (id: string): string =>
  `${github.context.serverUrl}/${github.context.repo.owner}/${github.context.repo.repo}/attestations/${id}`
+
+// Log the detected attestation type
+const logAttestationType = (type: AttestationType): void => {
+  const typeLabels: Record<AttestationType, string> = {
+    provenance: 'Build Provenance',
+    sbom: 'SBOM',
+    custom: 'Custom'
+  }
+  core.info(`Attestation type: ${typeLabels[type]}`)
+}
+
+// Generate predicate based on attestation type
+const getPredicateForType = async (
+  type: AttestationType,
+  inputs: RunInputs
+): Promise<Predicate> => {
+  switch (type) {
+    case 'provenance':
+      return generateProvenancePredicate()
+    case 'sbom': {
+      const sbom = await parseSBOMFromPath(inputs.sbomPath)
+      return generateSBOMPredicate(sbom)
+    }
+    case 'custom':
+      return predicateFromInputs(inputs)
+  }
+}
@@ -1,4 +1,4 @@
-import fs from 'fs'
+import fs from 'fs/promises'

 import type { Predicate } from '@actions/attest'

@@ -12,7 +12,9 @@ const MAX_PREDICATE_SIZE_BYTES = 16 * 1024 * 1024

 // Returns the predicate specified by the action's inputs. The predicate value
 // may be specified as a path to a file or as a string.
-export const predicateFromInputs = (inputs: PredicateInputs): Predicate => {
+export const predicateFromInputs = async (
+  inputs: PredicateInputs
+): Promise<Predicate> => {
  const { predicateType, predicate, predicatePath } = inputs

  if (!predicateType) {
@@ -30,18 +32,22 @@ export const predicateFromInputs = (inputs: PredicateInputs): Predicate => {
  let params: string = predicate

  if (predicatePath) {
-    if (!fs.existsSync(predicatePath)) {
+    try {
+      await fs.access(predicatePath)
+    } catch {
      throw new Error(`predicate file not found: ${predicatePath}`)
    }

+    const stat = await fs.stat(predicatePath)
+
    /* istanbul ignore next */
-    if (fs.statSync(predicatePath).size > MAX_PREDICATE_SIZE_BYTES) {
+    if (stat.size > MAX_PREDICATE_SIZE_BYTES) {
      throw new Error(
        `predicate file exceeds maximum allowed size: ${MAX_PREDICATE_SIZE_BYTES} bytes`
      )
    }

-    params = fs.readFileSync(predicatePath, 'utf-8')
+    params = await fs.readFile(predicatePath, 'utf-8')
  } else {
    if (predicate.length > MAX_PREDICATE_SIZE_BYTES) {
      throw new Error(
@@ -0,0 +1,7 @@
+import { buildSLSAProvenancePredicate } from '@actions/attest'
+
+import type { Predicate } from '@actions/attest'
+
+export const generateProvenancePredicate = async (): Promise<Predicate> => {
+  return buildSLSAProvenancePredicate()
+}
@@ -0,0 +1,87 @@
+import fs from 'fs/promises'
+
+import type { Predicate } from '@actions/attest'
+
+export type SBOM = {
+  type: 'spdx' | 'cyclonedx'
+  object: object
+}
+
+// SBOMs cannot exceed 16MB.
+const MAX_SBOM_SIZE_BYTES = 16 * 1024 * 1024
+
+export const parseSBOMFromPath = async (filePath: string): Promise<SBOM> => {
+  const fileContent = await fs.readFile(filePath, 'utf8')
+
+  const stats = await fs.stat(filePath)
+  if (stats.size > MAX_SBOM_SIZE_BYTES) {
+    throw new Error(
+      `SBOM file exceeds maximum allowed size: ${MAX_SBOM_SIZE_BYTES} bytes`
+    )
+  }
+
+  const sbom = JSON.parse(fileContent) as object
+
+  if (checkIsSPDX(sbom)) {
+    return { type: 'spdx', object: sbom }
+  } else if (checkIsCycloneDX(sbom)) {
+    return { type: 'cyclonedx', object: sbom }
+  }
+
+  throw new Error(
+    'Unsupported SBOM format. Must be valid SPDX or CycloneDX JSON.'
+  )
+}
+
+const checkIsSPDX = (sbomObject: {
+  spdxVersion?: string
+  SPDXID?: string
+}): boolean => {
+  return !!(sbomObject?.spdxVersion && sbomObject?.SPDXID)
+}
+
+const checkIsCycloneDX = (sbomObject: {
+  bomFormat?: string
+  serialNumber?: string
+  specVersion?: string
+}): boolean => {
+  return !!(
+    sbomObject?.bomFormat &&
+    sbomObject?.serialNumber &&
+    sbomObject?.specVersion
+  )
+}
+
+export const generateSBOMPredicate = (sbom: SBOM): Predicate => {
+  switch (sbom.type) {
+    case 'spdx':
+      return generateSPDXPredicate(sbom.object)
+    case 'cyclonedx':
+      return generateCycloneDXPredicate(sbom.object)
+    default:
+      throw new Error('Unsupported SBOM format')
+  }
+}
+
+// ref: https://github.com/in-toto/attestation/blob/main/spec/predicates/spdx.md
+const generateSPDXPredicate = (sbom: object): Predicate => {
+  const spdxVersion = (sbom as { spdxVersion?: string })?.['spdxVersion']
+  if (!spdxVersion) {
+    throw new Error('Cannot find spdxVersion in the SBOM')
+  }
+
+  const version = spdxVersion.split('-')[1]
+
+  return {
+    type: `https://spdx.dev/Document/v${version}`,
+    params: sbom
+  }
+}
+
+// ref: https://github.com/in-toto/attestation/blob/main/spec/predicates/cyclonedx.md
+const generateCycloneDXPredicate = (sbom: object): Predicate => {
+  return {
+    type: 'https://cyclonedx.org/bom',
+    params: sbom
+  }
+}
@@ -1,18 +1,24 @@
 import * as glob from '@actions/glob'
+import assert from 'assert'
 import crypto from 'crypto'
 import { parse } from 'csv-parse/sync'
-import fs from 'fs'
+import { createReadStream } from 'fs'
+import fs from 'fs/promises'
+import os from 'os'
 import path from 'path'

 import type { Subject } from '@actions/attest'

 const MAX_SUBJECT_COUNT = 1024
+const MAX_SUBJECT_CHECKSUM_SIZE_BYTES = 512 * MAX_SUBJECT_COUNT
 const DIGEST_ALGORITHM = 'sha256'
+const HEX_STRING_RE = /^[0-9a-fA-F]+$/

 export type SubjectInputs = {
  subjectPath: string
  subjectName: string
  subjectDigest: string
+  subjectChecksums: string
  downcaseName?: boolean
 }
 // Returns the subject specified by the action's inputs. The subject may be
@@ -22,15 +28,26 @@ export type SubjectInputs = {
 export const subjectFromInputs = async (
  inputs: SubjectInputs
 ): Promise<Subject[]> => {
-  const { subjectPath, subjectDigest, subjectName, downcaseName } = inputs
+  const {
+    subjectPath,
+    subjectDigest,
+    subjectName,
+    subjectChecksums,
+    downcaseName
+  } = inputs

-  if (!subjectPath && !subjectDigest) {
-    throw new Error('One of subject-path or subject-digest must be provided')
+  const enabledInputs = [subjectPath, subjectDigest, subjectChecksums].filter(
+    Boolean
+  )
+  if (enabledInputs.length === 0) {
+    throw new Error(
+      'One of subject-path, subject-digest, or subject-checksums must be provided'
+    )
  }

-  if (subjectPath && subjectDigest) {
+  if (enabledInputs.length > 1) {
    throw new Error(
-      'Only one of subject-path or subject-digest may be provided'
+      'Only one of subject-path, subject-digest, or subject-checksums may be provided'
    )
  }

@@ -42,10 +59,17 @@ export const subjectFromInputs = async (
  // to conform to OCI image naming conventions
  const name = downcaseName ? subjectName.toLowerCase() : subjectName

-  if (subjectPath) {
-    return await getSubjectFromPath(subjectPath, name)
-  } else {
-    return [getSubjectFromDigest(subjectDigest, name)]
+  switch (true) {
+    case !!subjectPath:
+      return getSubjectFromPath(subjectPath, name)
+    case !!subjectDigest:
+      return [getSubjectFromDigest(subjectDigest, name)]
+    case !!subjectChecksums:
+      return await getSubjectFromChecksums(subjectChecksums)
+    /* istanbul ignore next */
+    default:
+      // This should be unreachable, but TS requires a default case
+      assert.fail('unreachable')
  }
 }

@@ -65,26 +89,37 @@ const getSubjectFromPath = async (
  const digestedSubjects: Subject[] = []

  // Parse the list of subject paths
-  const subjectPaths = parseList(subjectPath).join('\n')
+  const subjectPaths = parseSubjectPathList(subjectPath).join('\n')

  // Expand the globbed paths to a list of actual paths
-  /* eslint-disable-next-line github/no-then */
  const paths = await glob.create(subjectPaths).then(async g => g.glob())

-  // Filter path list to just the files (not directories)
-  const files = paths.filter(p => fs.statSync(p).isFile())
-
-  if (files.length > MAX_SUBJECT_COUNT) {
-    throw new Error(
-      `Too many subjects specified. The maximum number of subjects is ${MAX_SUBJECT_COUNT}.`
-    )
+  // Filter path list to just the files (not directories), enforcing the maximum
+  const files: string[] = []
+  for (const p of paths) {
+    const stat = await fs.stat(p)
+    if (stat.isFile()) {
+      if (files.length >= MAX_SUBJECT_COUNT) {
+        throw new Error(
+          `Too many subjects specified (>${MAX_SUBJECT_COUNT}). The maximum number of subjects is ${MAX_SUBJECT_COUNT}.`
+        )
+      }
+      files.push(p)
+    }
  }

  for (const file of files) {
    const name = subjectName || path.parse(file).base
    const digest = await digestFile(DIGEST_ALGORITHM, file)

-    digestedSubjects.push({ name, digest: { [DIGEST_ALGORITHM]: digest } })
+    // Only add the subject if it is not already in the list
+    if (
+      !digestedSubjects.some(
+        s => s.name === name && s.digest[DIGEST_ALGORITHM] === digest
+      )
+    ) {
+      digestedSubjects.push({ name, digest: { [DIGEST_ALGORITHM]: digest } })
+    }
  }

  if (digestedSubjects.length === 0) {
@@ -113,6 +148,78 @@ const getSubjectFromDigest = (
  }
 }

+const getSubjectFromChecksums = async (
+  subjectChecksums: string
+): Promise<Subject[]> => {
+  try {
+    await fs.access(subjectChecksums)
+    return getSubjectFromChecksumsFile(subjectChecksums)
+  } catch {
+    return getSubjectFromChecksumsString(subjectChecksums)
+  }
+}
+
+const getSubjectFromChecksumsFile = async (
+  checksumsPath: string
+): Promise<Subject[]> => {
+  const stats = await fs.stat(checksumsPath)
+  if (!stats.isFile()) {
+    throw new Error(`subject checksums file not found: ${checksumsPath}`)
+  }
+
+  /* istanbul ignore next */
+  if (stats.size > MAX_SUBJECT_CHECKSUM_SIZE_BYTES) {
+    throw new Error(
+      `subject checksums file exceeds maximum allowed size: ${MAX_SUBJECT_CHECKSUM_SIZE_BYTES} bytes`
+    )
+  }
+
+  const checksums = await fs.readFile(checksumsPath, 'utf-8')
+  return getSubjectFromChecksumsString(checksums)
+}
+
+const getSubjectFromChecksumsString = (checksums: string): Subject[] => {
+  const subjects: Subject[] = []
+
+  const records: string[] = checksums.split(os.EOL).filter(Boolean)
+
+  for (const record of records) {
+    // Find the space delimiter following the digest
+    const delimIndex = record.indexOf(' ')
+
+    // Skip any line that doesn't have a delimiter
+    if (delimIndex === -1) {
+      continue
+    }
+
+    // It's common for checksum records to have a leading flag character before
+    // the artifact name. It will be either a '*' or a space.
+    const flag_and_name = record.slice(delimIndex + 1)
+    const name =
+      flag_and_name.startsWith('*') || flag_and_name.startsWith(' ')
+        ? flag_and_name.slice(1)
+        : flag_and_name
+
+    const digest = record.slice(0, delimIndex)
+
+    if (!HEX_STRING_RE.test(digest)) {
+      throw new Error(`Invalid digest: ${digest}`)
+    }
+
+    const alg = digestAlgorithm(digest)
+
+    // Only add the subject if it is not already in the list (deduplicate by name & digest)
+    if (!subjects.some(s => s.name === name && s.digest[alg] === digest)) {
+      subjects.push({
+        name,
+        digest: { [alg]: digest }
+      })
+    }
+  }
+
+  return subjects
+}
+
 // Calculates the digest of a file using the specified algorithm. The file is
 // streamed into the digest function to avoid loading the entire file into
 // memory. The returned digest is a hex string.
@@ -122,14 +229,14 @@ const digestFile = async (
 ): Promise<string> => {
  return new Promise((resolve, reject) => {
    const hash = crypto.createHash(algorithm).setEncoding('hex')
-    fs.createReadStream(filePath)
+    createReadStream(filePath)
      .once('error', reject)
      .pipe(hash)
      .once('finish', () => resolve(hash.read()))
  })
 }

-const parseList = (input: string): string[] => {
+const parseSubjectPathList = (input: string): string[] => {
  const res: string[] = []

  const records: string[][] = parse(input, {
@@ -145,3 +252,14 @@ const parseList = (input: string): string[] => {

  return res.filter(item => item).map(pat => pat.trim())
 }
+
+const digestAlgorithm = (digest: string): string => {
+  switch (digest.length) {
+    case 64:
+      return 'sha256'
+    case 128:
+      return 'sha512'
+    default:
+      throw new Error(`Unknown digest algorithm: ${digest}`)
+  }
+}
@@ -2,9 +2,10 @@
  "$schema": "https://json.schemastore.org/tsconfig",
  "compilerOptions": {
    "target": "ES2022",
-    "module": "NodeNext",
+    "module": "ESNext",
    "rootDir": "./src",
-    "moduleResolution": "NodeNext",
+    "moduleResolution": "Bundler",
+    "isolatedModules": true,
    "baseUrl": "./",
    "sourceMap": true,
    "outDir": "./dist",
@@ -0,0 +1,9 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "noEmit": true
+  },
+  "include": ["./__tests__/**/*", "./src/**/*"],
+  "exclude": ["./dist", "./node_modules", "./coverage", "*.json"]
+}
@@ -1 +1 @@
 .6.0
 .5.0