update error wording (#2467)

* block checking out fork pr for some events

* address copilot and reviewer feedback

* run prettier formatting

* build

* update urls

* update readme

* update description and url again

* edit url one more time

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## v3.6.0
+- [Fix: Mark test scripts with Bash'isms to be run via Bash](https://github.com/actions/checkout/pull/1377)
+- [Add option to fetch tags even if fetch-depth > 0](https://github.com/actions/checkout/pull/579)
+
 ## v3.5.3
 - [Fix: Checkout fail in self-hosted runners when faulty submodule are checked-in](https://github.com/actions/checkout/pull/1196)
 - [Fix typos found by codespell](https://github.com/actions/checkout/pull/1287)

README.md

@@ -87,6 +87,10 @@ When Git 2.18 or higher is not in your PATH, falls back to the REST API to downl
     # Default: 1
     fetch-depth: ''
 
+    # Whether to fetch tags, even if fetch-depth > 0.
+    # Default: false
+    fetch-tags: ''
+
     # Whether to download Git-LFS files
     # Default: false
     lfs: ''
@@ -110,6 +114,15 @@ When Git 2.18 or higher is not in your PATH, falls back to the REST API to downl
     # running from unless specified. Example URLs are https://github.com or
     # https://my-ghes-server.example.com
     github-server-url: ''
+
+    # Required to check out fork pull request code from a workflow triggered by
+    # `pull_request_target` or `workflow_run`. These workflows run with the base
+    # repository's GITHUB_TOKEN, secrets, default-branch cache scope, and runner
+    # access; fetching and executing a fork's code in that trusted context commonly
+    # leads to "pwn request" vulnerabilities. Set to `true` only after reviewing the
+    # risks at https://gh.io/securely-using-pull_request_target.
+    # Default: false
+    allow-unsafe-pr-checkout: ''
 ```
 <!-- end usage -->
 

__test__/git-auth-helper.test.ts

@@ -805,6 +805,7 @@ async function setup(testName: string): Promise<void> {
     sparseCheckout: [],
     sparseCheckoutConeMode: true,
     fetchDepth: 1,
+    fetchTags: false,
     lfs: false,
     submodules: false,
     nestedSubmodules: false,
@@ -818,7 +819,8 @@ async function setup(testName: string): Promise<void> {
     sshStrict: true,
     workflowOrganizationId: 123456,
     setSafeDirectory: true,
-    githubServerUrl: githubServerUrl
+    githubServerUrl: githubServerUrl,
+    allowUnsafePrCheckout: false
   }
 }
 

__test__/git-command-manager.test.ts

@@ -88,3 +88,179 @@ describe('git-auth-helper tests', () => {
     expect(branches.sort()).toEqual(['foo'].sort())
   })
 })
+
+describe('Test fetchDepth and fetchTags options', () => {
+  beforeEach(async () => {
+    jest.spyOn(fshelper, 'fileExistsSync').mockImplementation(jest.fn())
+    jest.spyOn(fshelper, 'directoryExistsSync').mockImplementation(jest.fn())
+    mockExec.mockImplementation((path, args, options) => {
+      console.log(args, options.listeners.stdout)
+
+      if (args.includes('version')) {
+        options.listeners.stdout(Buffer.from('2.18'))
+      }
+
+      return 0
+    })
+  })
+
+  afterEach(() => {
+    jest.restoreAllMocks()
+  })
+
+  it('should call execGit with the correct arguments when fetchDepth is 0 and fetchTags is true', async () => {
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+
+    const refSpec = ['refspec1', 'refspec2']
+    const options = {
+      filter: 'filterValue',
+      fetchDepth: 0,
+      fetchTags: true
+    }
+
+    await git.fetch(refSpec, options)
+
+    expect(mockExec).toHaveBeenCalledWith(
+      expect.any(String),
+      [
+        '-c',
+        'protocol.version=2',
+        'fetch',
+        '--prune',
+        '--progress',
+        '--no-recurse-submodules',
+        '--filter=filterValue',
+        'origin',
+        'refspec1',
+        'refspec2'
+      ],
+      expect.any(Object)
+    )
+  })
+
+  it('should call execGit with the correct arguments when fetchDepth is 0 and fetchTags is false', async () => {
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+    const refSpec = ['refspec1', 'refspec2']
+    const options = {
+      filter: 'filterValue',
+      fetchDepth: 0,
+      fetchTags: false
+    }
+
+    await git.fetch(refSpec, options)
+
+    expect(mockExec).toHaveBeenCalledWith(
+      expect.any(String),
+      [
+        '-c',
+        'protocol.version=2',
+        'fetch',
+        '--no-tags',
+        '--prune',
+        '--progress',
+        '--no-recurse-submodules',
+        '--filter=filterValue',
+        'origin',
+        'refspec1',
+        'refspec2'
+      ],
+      expect.any(Object)
+    )
+  })
+
+  it('should call execGit with the correct arguments when fetchDepth is 1 and fetchTags is false', async () => {
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+    const refSpec = ['refspec1', 'refspec2']
+    const options = {
+      filter: 'filterValue',
+      fetchDepth: 1,
+      fetchTags: false
+    }
+
+    await git.fetch(refSpec, options)
+
+    expect(mockExec).toHaveBeenCalledWith(
+      expect.any(String),
+      [
+        '-c',
+        'protocol.version=2',
+        'fetch',
+        '--no-tags',
+        '--prune',
+        '--progress',
+        '--no-recurse-submodules',
+        '--filter=filterValue',
+        '--depth=1',
+        'origin',
+        'refspec1',
+        'refspec2'
+      ],
+      expect.any(Object)
+    )
+  })
+
+  it('should call execGit with the correct arguments when fetchDepth is 1 and fetchTags is true', async () => {
+    jest.spyOn(exec, 'exec').mockImplementation(mockExec)
+
+    const workingDirectory = 'test'
+    const lfs = false
+    const doSparseCheckout = false
+    git = await commandManager.createCommandManager(
+      workingDirectory,
+      lfs,
+      doSparseCheckout
+    )
+    const refSpec = ['refspec1', 'refspec2']
+    const options = {
+      filter: 'filterValue',
+      fetchDepth: 1,
+      fetchTags: true
+    }
+
+    await git.fetch(refSpec, options)
+
+    expect(mockExec).toHaveBeenCalledWith(
+      expect.any(String),
+      [
+        '-c',
+        'protocol.version=2',
+        'fetch',
+        '--prune',
+        '--progress',
+        '--no-recurse-submodules',
+        '--filter=filterValue',
+        '--depth=1',
+        'origin',
+        'refspec1',
+        'refspec2'
+      ],
+      expect.any(Object)
+    )
+  })
+})

__test__/input-helper.test.ts

@@ -82,12 +82,14 @@ describe('input-helper tests', () => {
     expect(settings.sparseCheckout).toBe(undefined)
     expect(settings.sparseCheckoutConeMode).toBe(true)
     expect(settings.fetchDepth).toBe(1)
+    expect(settings.fetchTags).toBe(false)
     expect(settings.lfs).toBe(false)
     expect(settings.ref).toBe('refs/heads/some-ref')
     expect(settings.repositoryName).toBe('some-repo')
     expect(settings.repositoryOwner).toBe('some-owner')
     expect(settings.repositoryPath).toBe(gitHubWorkspace)
     expect(settings.setSafeDirectory).toBe(true)
+    expect(settings.allowUnsafePrCheckout).toBe(false)
   })
 
   it('qualifies ref', async () => {

__test__/unsafe-pr-checkout-helper.test.ts

@@ -0,0 +1,267 @@
+import * as github from '@actions/github'
+import {assertSafePrCheckout} from '../lib/unsafe-pr-checkout-helper'
+
+// Shallow clone original @actions/github context
+const originalContext = {...github.context}
+const originalEventName = github.context.eventName
+const originalPayload = github.context.payload
+
+const BASE_REPO_ID = 100
+const FORK_REPO_ID = 200
+const PR_HEAD_SHA = '1111111111111111111111111111111111111111'
+const PR_MERGE_SHA = '2222222222222222222222222222222222222222'
+const SAFE_BASE_SHA = '3333333333333333333333333333333333333333'
+const WORKFLOW_RUN_HEAD_COMMIT_SHA = '4444444444444444444444444444444444444444'
+const BASE_QUALIFIED_REPO = 'some-owner/some-repo'
+const FORK_QUALIFIED_REPO = 'another-repo/fork'
+
+function setContext(eventName: string, payload: object): void {
+  ;(github.context as {eventName: string}).eventName = eventName
+  ;(github.context as {payload: object}).payload = payload
+}
+
+function forkPullRequestTargetPayload(): object {
+  return {
+    repository: {id: BASE_REPO_ID},
+    pull_request: {
+      head: {
+        sha: PR_HEAD_SHA,
+        repo: {id: FORK_REPO_ID, full_name: FORK_QUALIFIED_REPO}
+      },
+      merge_commit_sha: PR_MERGE_SHA
+    }
+  }
+}
+
+function sameRepoPullRequestTargetPayload(): object {
+  return {
+    repository: {id: BASE_REPO_ID},
+    pull_request: {
+      head: {
+        sha: PR_HEAD_SHA,
+        repo: {id: BASE_REPO_ID, full_name: BASE_QUALIFIED_REPO}
+      },
+      merge_commit_sha: PR_MERGE_SHA
+    }
+  }
+}
+
+function forkWorkflowRunPayload(): object {
+  return {
+    repository: {id: BASE_REPO_ID},
+    workflow_run: {
+      event: 'pull_request',
+      head_commit: {id: WORKFLOW_RUN_HEAD_COMMIT_SHA},
+      head_repository: {id: FORK_REPO_ID, full_name: FORK_QUALIFIED_REPO}
+    }
+  }
+}
+
+describe('unsafe-pr-checkout-helper', () => {
+  beforeAll(() => {
+    jest.spyOn(github.context, 'repo', 'get').mockReturnValue({
+      owner: 'some-owner',
+      repo: 'some-repo'
+    })
+  })
+
+  afterEach(() => {
+    ;(github.context as {eventName: string}).eventName = originalEventName
+    ;(github.context as {payload: object}).payload = originalPayload
+  })
+
+  afterAll(() => {
+    ;(github.context as {eventName: string}).eventName =
+      originalContext.eventName
+    ;(github.context as {payload: object}).payload = originalContext.payload
+    jest.restoreAllMocks()
+  })
+
+  it('allows pull_request events untouched', () => {
+    setContext('pull_request', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: 'attacker/fork',
+        ref: 'refs/pull/1/merge',
+        commit: '',
+        allowUnsafePrCheckout: false
+      })
+    ).not.toThrow()
+  })
+
+  it('allows pull_request_target default checkout (base branch)', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: 'refs/heads/main',
+        commit: SAFE_BASE_SHA,
+        allowUnsafePrCheckout: false
+      })
+    ).not.toThrow()
+  })
+
+  it('allows same-repo pull_request_target checkout of PR head', () => {
+    setContext('pull_request_target', sameRepoPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: '',
+        commit: PR_HEAD_SHA,
+        allowUnsafePrCheckout: false
+      })
+    ).not.toThrow()
+  })
+
+  it('refuses pull_request_target fork PR head SHA checkout', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: '',
+        commit: PR_HEAD_SHA,
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow(/Refusing to check out fork pull request code/)
+  })
+
+  it('refuses pull_request_target fork PR merge_commit_sha checkout', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: '',
+        commit: PR_MERGE_SHA,
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow(/allow-unsafe-pr-checkout/)
+  })
+
+  it('refuses pull_request_target fork PR ref pattern (head)', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: 'refs/pull/42/head',
+        commit: '',
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow()
+  })
+
+  it('refuses pull_request_target fork PR ref pattern (merge)', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: 'refs/pull/42/merge',
+        commit: '',
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow()
+  })
+
+  it('refuses pull_request_target when repository points at the fork', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: FORK_QUALIFIED_REPO,
+        ref: 'refs/heads/main',
+        commit: '',
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow()
+  })
+
+  it('allows pull_request_target checkout of an unrelated third-party repo', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: 'some-other/unrelated',
+        ref: 'refs/heads/main',
+        commit: '',
+        allowUnsafePrCheckout: false
+      })
+    ).not.toThrow()
+  })
+
+  it('refuses pull_request_target ignoring repository case differences', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: FORK_QUALIFIED_REPO.toUpperCase(),
+        ref: '',
+        commit: '',
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow()
+  })
+
+  it('refuses pull_request_target ignoring commit SHA case differences', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: '',
+        commit: PR_HEAD_SHA.toUpperCase(),
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow()
+  })
+
+  it('allows pull_request_target fork PR checkout when opted in', () => {
+    setContext('pull_request_target', forkPullRequestTargetPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: 'refs/pull/42/merge',
+        commit: '',
+        allowUnsafePrCheckout: true
+      })
+    ).not.toThrow()
+  })
+
+  it('refuses workflow_run fork PR head_commit.id checkout', () => {
+    setContext('workflow_run', forkWorkflowRunPayload())
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: '',
+        commit: WORKFLOW_RUN_HEAD_COMMIT_SHA,
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow()
+  })
+
+  it('refuses workflow_run with pull_request_target underlying event', () => {
+    const payload = forkWorkflowRunPayload() as {
+      workflow_run: {event: string}
+    }
+    payload.workflow_run.event = 'pull_request_target'
+    setContext('workflow_run', payload)
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: '',
+        commit: WORKFLOW_RUN_HEAD_COMMIT_SHA,
+        allowUnsafePrCheckout: false
+      })
+    ).toThrow()
+  })
+
+  it('allows workflow_run same-repo PR (head_repository.id matches base)', () => {
+    const payload = forkWorkflowRunPayload() as {
+      workflow_run: {head_repository: {id: number}}
+    }
+    payload.workflow_run.head_repository.id = BASE_REPO_ID
+    setContext('workflow_run', payload)
+    expect(() =>
+      assertSafePrCheckout({
+        qualifiedRepository: BASE_QUALIFIED_REPO,
+        ref: '',
+        commit: WORKFLOW_RUN_HEAD_COMMIT_SHA,
+        allowUnsafePrCheckout: false
+      })
+    ).not.toThrow()
+  })
+})

__test__/verify-sparse-checkout-non-cone-mode.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 # Verify .git folder
 if [ ! -d "./sparse-checkout-non-cone-mode/.git" ]; then

__test__/verify-sparse-checkout.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 # Verify .git folder
 if [ ! -d "./sparse-checkout/.git" ]; then

action.yml

@@ -65,6 +65,9 @@ inputs:
   fetch-depth:
     description: 'Number of commits to fetch. 0 indicates all history for all branches and tags.'
     default: 1
+  fetch-tags:
+    description: 'Whether to fetch tags, even if fetch-depth > 0.'
+    default: false
   lfs:
     description: 'Whether to download Git-LFS files'
     default: false
@@ -83,6 +86,15 @@ inputs:
   github-server-url:
     description: The base URL for the GitHub instance that you are trying to clone from, will use environment defaults to fetch from the same instance that the workflow is running from unless specified. Example URLs are https://github.com or https://my-ghes-server.example.com
     required: false
+  allow-unsafe-pr-checkout:
+    description: >
+      Required to check out fork pull request code from a workflow triggered by
+      `pull_request_target` or `workflow_run`. These workflows run with the
+      base repository's GITHUB_TOKEN, secrets, default-branch cache scope, and
+      runner access; fetching and executing a fork's code in that trusted
+      context commonly leads to "pwn request" vulnerabilities. Set to `true`
+      only after reviewing the risks at https://gh.io/securely-using-pull_request_target.
+    default: false
 runs:
   using: node16
   main: dist/index.js

dist/index.js

@@ -637,7 +637,7 @@ class GitCommandManager {
     fetch(refSpec, options) {
         return __awaiter(this, void 0, void 0, function* () {
             const args = ['-c', 'protocol.version=2', 'fetch'];
-            if (!refSpec.some(x => x === refHelper.tagsRefSpec)) {
+            if (!refSpec.some(x => x === refHelper.tagsRefSpec) && !options.fetchTags) {
                 args.push('--no-tags');
             }
             args.push('--prune', '--progress', '--no-recurse-submodules');
@@ -718,8 +718,8 @@ class GitCommandManager {
     }
     log1(format) {
         return __awaiter(this, void 0, void 0, function* () {
-            var args = format ? ['log', '-1', format] : ['log', '-1'];
-            var silent = format ? false : true;
+            const args = format ? ['log', '-1', format] : ['log', '-1'];
+            const silent = format ? false : true;
             const output = yield this.execGit(args, false, silent);
             return output.stdout;
         });
@@ -1256,6 +1256,7 @@ function getSource(settings) {
             }
             else {
                 fetchOptions.fetchDepth = settings.fetchDepth;
+                fetchOptions.fetchTags = settings.fetchTags;
                 const refSpec = refHelper.getRefSpec(settings.ref, settings.commit);
                 yield git.fetch(refSpec, fetchOptions);
             }
@@ -1663,6 +1664,7 @@ const core = __importStar(__nccwpck_require__(2186));
 const fsHelper = __importStar(__nccwpck_require__(7219));
 const github = __importStar(__nccwpck_require__(5438));
 const path = __importStar(__nccwpck_require__(1017));
+const unsafePrCheckoutHelper = __importStar(__nccwpck_require__(843));
 const workflowContextHelper = __importStar(__nccwpck_require__(9568));
 function getInputs() {
     return __awaiter(this, void 0, void 0, function* () {
@@ -1734,6 +1736,10 @@ function getInputs() {
             result.fetchDepth = 0;
         }
         core.debug(`fetch depth = ${result.fetchDepth}`);
+        // Fetch tags
+        result.fetchTags =
+            (core.getInput('fetch-tags') || 'false').toUpperCase() === 'TRUE';
+        core.debug(`fetch tags = ${result.fetchTags}`);
         // LFS
         result.lfs = (core.getInput('lfs') || 'false').toUpperCase() === 'TRUE';
         core.debug(`lfs = ${result.lfs}`);
@@ -1768,6 +1774,17 @@ function getInputs() {
         // Determine the GitHub URL that the repository is being hosted from
         result.githubServerUrl = core.getInput('github-server-url');
         core.debug(`GitHub Host URL = ${result.githubServerUrl}`);
+        // Allow unsafe PR checkout (opt-in for pull_request_target / workflow_run fork PRs)
+        result.allowUnsafePrCheckout =
+            (core.getInput('allow-unsafe-pr-checkout') || 'false').toUpperCase() ===
+                'TRUE';
+        core.debug(`allow unsafe PR checkout = ${result.allowUnsafePrCheckout}`);
+        unsafePrCheckoutHelper.assertSafePrCheckout({
+            qualifiedRepository,
+            ref: result.ref,
+            commit: result.commit,
+            allowUnsafePrCheckout: result.allowUnsafePrCheckout
+        });
         return result;
     });
 }
@@ -1894,7 +1911,7 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, ge
     });
 };
 Object.defineProperty(exports, "__esModule", ({ value: true }));
-exports.checkCommitInfo = exports.testRef = exports.getRefSpec = exports.getRefSpecForAllHistory = exports.getCheckoutInfo = exports.tagsRefSpec = void 0;
+exports.fromPayload = exports.checkCommitInfo = exports.testRef = exports.getRefSpec = exports.getRefSpecForAllHistory = exports.getCheckoutInfo = exports.tagsRefSpec = void 0;
 const core = __importStar(__nccwpck_require__(2186));
 const github = __importStar(__nccwpck_require__(5438));
 const url_helper_1 = __nccwpck_require__(9437);
@@ -2116,6 +2133,7 @@ exports.checkCommitInfo = checkCommitInfo;
 function fromPayload(path) {
     return select(github.context.payload, path);
 }
+exports.fromPayload = fromPayload;
 function select(obj, path) {
     if (!obj) {
         return undefined;
@@ -2322,6 +2340,102 @@ if (!exports.IsPost) {
 }
 
 
+/***/ }),
+
+/***/ 843:
+/***/ (function(__unused_webpack_module, exports, __nccwpck_require__) {
+
+"use strict";
+
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
+    Object.defineProperty(o, "default", { enumerable: true, value: v });
+}) : function(o, v) {
+    o["default"] = v;
+});
+var __importStar = (this && this.__importStar) || function (mod) {
+    if (mod && mod.__esModule) return mod;
+    var result = {};
+    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    __setModuleDefault(result, mod);
+    return result;
+};
+Object.defineProperty(exports, "__esModule", ({ value: true }));
+exports.assertSafePrCheckout = void 0;
+const github = __importStar(__nccwpck_require__(5438));
+const ref_helper_1 = __nccwpck_require__(8601);
+const PR_REF_PATTERN = /^refs\/pull\/[0-9]+\/(?:head|merge)$/;
+function assertSafePrCheckout(input) {
+    if (input.allowUnsafePrCheckout) {
+        return;
+    }
+    const eventName = github.context.eventName;
+    if (eventName !== 'pull_request_target' && eventName !== 'workflow_run') {
+        return;
+    }
+    const baseRepoId = (0, ref_helper_1.fromPayload)('repository.id');
+    if (typeof baseRepoId !== 'number') {
+        return;
+    }
+    let prHeadRepoId;
+    let prHeadRepoFullName;
+    const prShas = [];
+    if (eventName === 'pull_request_target') {
+        prHeadRepoId = (0, ref_helper_1.fromPayload)('pull_request.head.repo.id');
+        prHeadRepoFullName = (0, ref_helper_1.fromPayload)('pull_request.head.repo.full_name');
+        pushIfSha(prShas, (0, ref_helper_1.fromPayload)('pull_request.head.sha'));
+        pushIfSha(prShas, (0, ref_helper_1.fromPayload)('pull_request.merge_commit_sha'));
+    }
+    else {
+        const wrEvent = (0, ref_helper_1.fromPayload)('workflow_run.event');
+        if (typeof wrEvent !== 'string' || !wrEvent.startsWith('pull_request')) {
+            return;
+        }
+        prHeadRepoId = (0, ref_helper_1.fromPayload)('workflow_run.head_repository.id');
+        prHeadRepoFullName = (0, ref_helper_1.fromPayload)('workflow_run.head_repository.full_name');
+        pushIfSha(prShas, (0, ref_helper_1.fromPayload)('workflow_run.head_commit.id'));
+        // For `pull_request_target`-triggered workflow_run, `head_sha` is the base
+        // default branch SHA (not the PR head)
+        if (wrEvent !== 'pull_request_target') {
+            pushIfSha(prShas, (0, ref_helper_1.fromPayload)('workflow_run.head_sha'));
+        }
+    }
+    // (A) Fork PR?
+    if (typeof prHeadRepoId !== 'number' || prHeadRepoId === baseRepoId) {
+        return;
+    }
+    // (B) We cannot check for all fork PR refs so check to see
+    // if the resolved input points to the fork PR sha we have in the payload
+    const repositoryMatchesPrHead = typeof prHeadRepoFullName === 'string' &&
+        input.qualifiedRepository.toLowerCase() === prHeadRepoFullName.toLowerCase();
+    const refMatchesPullPattern = PR_REF_PATTERN.test(input.ref);
+    const commitMatchesPrHeadSha = !!input.commit && prShas.includes(input.commit.toLowerCase());
+    if (!repositoryMatchesPrHead &&
+        !refMatchesPullPattern &&
+        !commitMatchesPrHeadSha) {
+        return;
+    }
+    throw new Error(`Refusing to check out fork pull request code from a '${eventName}' workflow. ` +
+        `This workflow runs with the base repository's GITHUB_TOKEN, secrets, default-branch ` +
+        `cache scope, and runner access. Fetching and executing a fork's code in that trusted ` +
+        `context commonly leads to "pwn request" vulnerabilities. To opt in, review the risks ` +
+        `at https://gh.io/securely-using-pull_request_target and set 'allow-unsafe-pr-checkout: true' ` +
+        `on the actions/checkout step.`);
+}
+exports.assertSafePrCheckout = assertSafePrCheckout;
+function pushIfSha(target, value) {
+    if (typeof value === 'string' && value.length > 0) {
+        target.push(value.toLowerCase());
+    }
+}
+
+
 /***/ }),
 
 /***/ 9437:

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "checkout",
-  "version": "3.5.3",
+  "version": "3.6.0",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "checkout",
-      "version": "3.5.3",
+      "version": "3.6.0",
       "license": "MIT",
       "dependencies": {
         "@actions/core": "^1.10.0",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "checkout",
-  "version": "3.5.3",
+  "version": "3.6.0",
   "description": "checkout action",
   "main": "lib/main.js",
   "scripts": {

src/git-command-manager.ts

@@ -33,6 +33,7 @@ export interface IGitCommandManager {
     options: {
       filter?: string
       fetchDepth?: number
+      fetchTags?: boolean
     }
   ): Promise<void>
   getDefaultBranch(repositoryUrl: string): Promise<string>
@@ -240,10 +241,10 @@ class GitCommandManager {
 
   async fetch(
     refSpec: string[],
-    options: {filter?: string; fetchDepth?: number}
+    options: {filter?: string; fetchDepth?: number; fetchTags?: boolean}
   ): Promise<void> {
     const args = ['-c', 'protocol.version=2', 'fetch']
-    if (!refSpec.some(x => x === refHelper.tagsRefSpec)) {
+    if (!refSpec.some(x => x === refHelper.tagsRefSpec) && !options.fetchTags) {
       args.push('--no-tags')
     }
 
@@ -333,8 +334,8 @@ class GitCommandManager {
   }
 
   async log1(format?: string): Promise<string> {
-    var args = format ? ['log', '-1', format] : ['log', '-1']
-    var silent = format ? false : true
+    const args = format ? ['log', '-1', format] : ['log', '-1']
+    const silent = format ? false : true
     const output = await this.execGit(args, false, silent)
     return output.stdout
   }

src/git-source-provider.ts

@@ -153,7 +153,11 @@ export async function getSource(settings: IGitSourceSettings): Promise<void> {
 
     // Fetch
     core.startGroup('Fetching the repository')
-    const fetchOptions: {filter?: string; fetchDepth?: number} = {}
+    const fetchOptions: {
+      filter?: string
+      fetchDepth?: number
+      fetchTags?: boolean
+    } = {}
     if (settings.sparseCheckout) fetchOptions.filter = 'blob:none'
     if (settings.fetchDepth <= 0) {
       // Fetch all branches and tags
@@ -171,6 +175,7 @@ export async function getSource(settings: IGitSourceSettings): Promise<void> {
       }
     } else {
       fetchOptions.fetchDepth = settings.fetchDepth
+      fetchOptions.fetchTags = settings.fetchTags
       const refSpec = refHelper.getRefSpec(settings.ref, settings.commit)
       await git.fetch(refSpec, fetchOptions)
     }

src/git-source-settings.ts

@@ -44,6 +44,11 @@ export interface IGitSourceSettings {
    */
   fetchDepth: number
 
+  /**
+   * Fetch tags, even if fetchDepth > 0 (default: false)
+   */
+  fetchTags: boolean
+
   /**
    * Indicates whether to fetch LFS objects
    */
@@ -98,4 +103,10 @@ export interface IGitSourceSettings {
    * User override on the GitHub Server/Host URL that hosts the repository to be cloned
    */
   githubServerUrl: string | undefined
+
+  /**
+   * Opt-in to allow checking out fork pull request code from a workflow
+   * triggered by pull_request_target or workflow_run.
+   */
+  allowUnsafePrCheckout: boolean
 }

src/input-helper.ts

@@ -2,6 +2,7 @@ import * as core from '@actions/core'
 import * as fsHelper from './fs-helper'
 import * as github from '@actions/github'
 import * as path from 'path'
+import * as unsafePrCheckoutHelper from './unsafe-pr-checkout-helper'
 import * as workflowContextHelper from './workflow-context-helper'
 import {IGitSourceSettings} from './git-source-settings'
 
@@ -100,6 +101,11 @@ export async function getInputs(): Promise<IGitSourceSettings> {
   }
   core.debug(`fetch depth = ${result.fetchDepth}`)
 
+  // Fetch tags
+  result.fetchTags =
+    (core.getInput('fetch-tags') || 'false').toUpperCase() === 'TRUE'
+  core.debug(`fetch tags = ${result.fetchTags}`)
+
   // LFS
   result.lfs = (core.getInput('lfs') || 'false').toUpperCase() === 'TRUE'
   core.debug(`lfs = ${result.lfs}`)
@@ -141,5 +147,18 @@ export async function getInputs(): Promise<IGitSourceSettings> {
   result.githubServerUrl = core.getInput('github-server-url')
   core.debug(`GitHub Host URL = ${result.githubServerUrl}`)
 
+  // Allow unsafe PR checkout (opt-in for pull_request_target / workflow_run fork PRs)
+  result.allowUnsafePrCheckout =
+    (core.getInput('allow-unsafe-pr-checkout') || 'false').toUpperCase() ===
+    'TRUE'
+  core.debug(`allow unsafe PR checkout = ${result.allowUnsafePrCheckout}`)
+
+  unsafePrCheckoutHelper.assertSafePrCheckout({
+    qualifiedRepository,
+    ref: result.ref,
+    commit: result.commit,
+    allowUnsafePrCheckout: result.allowUnsafePrCheckout
+  })
+
   return result
 }

src/ref-helper.ts

@@ -264,7 +264,7 @@ export async function checkCommitInfo(
   }
 }
 
-function fromPayload(path: string): any {
+export function fromPayload(path: string): any {
   return select(github.context.payload, path)
 }
 

src/unsafe-pr-checkout-helper.ts

@@ -0,0 +1,88 @@
+import * as github from '@actions/github'
+import {fromPayload} from './ref-helper'
+
+const PR_REF_PATTERN = /^refs\/pull\/[0-9]+\/(?:head|merge)$/
+
+export interface IUnsafePrCheckoutInput {
+  qualifiedRepository: string
+  ref: string
+  commit: string | undefined
+  allowUnsafePrCheckout: boolean
+}
+
+export function assertSafePrCheckout(input: IUnsafePrCheckoutInput): void {
+  if (input.allowUnsafePrCheckout) {
+    return
+  }
+
+  const eventName = github.context.eventName
+  if (eventName !== 'pull_request_target' && eventName !== 'workflow_run') {
+    return
+  }
+
+  const baseRepoId = fromPayload('repository.id')
+  if (typeof baseRepoId !== 'number') {
+    return
+  }
+
+  let prHeadRepoId: unknown
+  let prHeadRepoFullName: unknown
+  const prShas: string[] = []
+
+  if (eventName === 'pull_request_target') {
+    prHeadRepoId = fromPayload('pull_request.head.repo.id')
+    prHeadRepoFullName = fromPayload('pull_request.head.repo.full_name')
+    pushIfSha(prShas, fromPayload('pull_request.head.sha'))
+    pushIfSha(prShas, fromPayload('pull_request.merge_commit_sha'))
+  } else {
+    const wrEvent = fromPayload('workflow_run.event')
+    if (typeof wrEvent !== 'string' || !wrEvent.startsWith('pull_request')) {
+      return
+    }
+    prHeadRepoId = fromPayload('workflow_run.head_repository.id')
+    prHeadRepoFullName = fromPayload('workflow_run.head_repository.full_name')
+    pushIfSha(prShas, fromPayload('workflow_run.head_commit.id'))
+    // For `pull_request_target`-triggered workflow_run, `head_sha` is the base
+    // default branch SHA (not the PR head)
+    if (wrEvent !== 'pull_request_target') {
+      pushIfSha(prShas, fromPayload('workflow_run.head_sha'))
+    }
+  }
+
+  // (A) Fork PR?
+  if (typeof prHeadRepoId !== 'number' || prHeadRepoId === baseRepoId) {
+    return
+  }
+
+  // (B) We cannot check for all fork PR refs so check to see
+  // if the resolved input points to the fork PR sha we have in the payload
+  const repositoryMatchesPrHead =
+    typeof prHeadRepoFullName === 'string' &&
+    input.qualifiedRepository.toLowerCase() === prHeadRepoFullName.toLowerCase()
+  const refMatchesPullPattern = PR_REF_PATTERN.test(input.ref)
+  const commitMatchesPrHeadSha =
+    !!input.commit && prShas.includes(input.commit.toLowerCase())
+
+  if (
+    !repositoryMatchesPrHead &&
+    !refMatchesPullPattern &&
+    !commitMatchesPrHeadSha
+  ) {
+    return
+  }
+
+  throw new Error(
+    `Refusing to check out fork pull request code from a '${eventName}' workflow. ` +
+      `This workflow runs with the base repository's GITHUB_TOKEN, secrets, default-branch ` +
+      `cache scope, and runner access. Fetching and executing a fork's code in that trusted ` +
+      `context commonly leads to "pwn request" vulnerabilities. To opt in, review the risks ` +
+      `at https://gh.io/securely-using-pull_request_target and set 'allow-unsafe-pr-checkout: true' ` +
+      `on the actions/checkout step.`
+  )
+}
+
+function pushIfSha(target: string[], value: unknown): void {
+  if (typeof value === 'string' && value.length > 0) {
+    target.push(value.toLowerCase())
+  }
+}