Allow to seed the internal cache of gpg-agent with provided passphrase (#5)

Better handling of commands output streams

.github/workflows/ci.yml

@@ -32,3 +32,4 @@ jobs:
         uses: ./
         env:
           SIGNING_KEY: ${{ secrets.SIGNING_KEY_TEST }}
+          PASSPHRASE: ${{ secrets.PASSPHRASE_TEST }}

README.md

@@ -12,6 +12,12 @@ If you are interested, [check out](https://git.io/Je09Y) my other :octocat: GitH
 
 ![Import GPG key](.res/ghaction-import-gpg.png)
 
+## Features
+
+* Works on Linux, MacOS and Windows [virtual environments](https://help.github.com/en/articles/virtual-environments-for-github-actions#supported-virtual-environments-and-hardware-resources)
+* Allow to seed the internal cache of `gpg-agent` with provided passphrase
+* Purge imported GPG key and cache information from runner (security)
+
 ## Usage
 
 ```yaml
@@ -33,6 +39,7 @@ jobs:
         uses: crazy-max/ghaction-import-gpg@master
         env:
           SIGNING_KEY: ${{ secrets.SIGNING_KEY }}
+          PASSPHRASE: ${{ secrets.PASSPHRASE }}
 ```
 
 ## Customizing
@@ -44,6 +51,7 @@ Following environment variables can be used as `step.env` keys
 | Name           | Description                           |
 |----------------|---------------------------------------|
 | `SIGNING_KEY`  | GPG private key exported as an ASCII armored version |
+| `PASSPHRASE`   | Passphrase of your GPG key if setted for your `SIGNING_KEY` |
 
 ## How can I help?
 

__tests__/gpg.test.ts

@@ -1,5 +1,4 @@
-import {deleteKey, getVersion, importKey} from '../src/gpg';
-import * as child_process from 'child_process';
+import * as gpg from '../src/gpg';
 
 const userInfo = {
   name: 'Joe Tester',
@@ -8,6 +7,7 @@ const userInfo = {
   keyID: 'D523BD50DD70B0BA',
   userID: 'Joe Tester <joe@foo.bar>',
   fingerprint: '27571A53B86AF0C799B38BA77D851EB72D73BDA0',
+  keygrip: 'BA83FC8947213477F28ADC019F6564A956456163',
   pgp: `-----BEGIN PGP PRIVATE KEY BLOCK-----
 
 lQdGBF6tzaABEACjFbX7PFEG6vDPN2MPyxYW7/3o/sonORj4HXUFjFxxJxktJ3x3
@@ -119,7 +119,7 @@ PejgXO0uIRolYQ3sz2tMGhx1MfBqH64=
 describe('gpg', () => {
   describe('getVersion', () => {
     it('returns GnuPG and libgcrypt version', async () => {
-      await getVersion().then(version => {
+      await gpg.getVersion().then(version => {
         console.log(version);
         expect(version.gnupg).not.toEqual('');
         expect(version.libgcrypt).not.toEqual('');
@@ -127,25 +127,58 @@ describe('gpg', () => {
     });
   });
 
+  describe('getDirs', () => {
+    it('returns GnuPG dirs', async () => {
+      await gpg.getDirs().then(dirs => {
+        console.log(dirs);
+        expect(dirs.libdir).not.toEqual('');
+        expect(dirs.datadir).not.toEqual('');
+        expect(dirs.homedir).not.toEqual('');
+      });
+    });
+  });
+
   describe('importKey', () => {
     it('imports key to GnuPG', async () => {
-      await importKey(userInfo.pgp).then(() => {
-        console.log(
-          child_process.execSync(`gpg --batch --list-keys --keyid-format LONG ${userInfo.email}`, {encoding: 'utf8'})
-        );
-        console.log(
-          child_process.execSync(`gpg --batch --list-secret-keys --keyid-format LONG ${userInfo.email}`, {
-            encoding: 'utf8'
-          })
-        );
+      await gpg.importKey(userInfo.pgp).then(output => {
+        console.log(output);
+        expect(output).not.toEqual('');
+      });
+    });
+  });
+
+  describe('getKeygrip', () => {
+    it('returns the keygrip', async () => {
+      await gpg.importKey(userInfo.pgp);
+      await gpg.getKeygrip(userInfo.fingerprint).then(keygrip => {
+        console.log(keygrip);
+        expect(keygrip).toEqual(userInfo.keygrip);
+      });
+    });
+  });
+
+  describe('configureAgent', () => {
+    it('configures GnuPG agent', async () => {
+      await gpg.configureAgent(gpg.agentConfig);
+    });
+  });
+
+  describe('presetPassphrase', () => {
+    it('presets passphrase', async () => {
+      await gpg.importKey(userInfo.pgp);
+      const keygrip = await gpg.getKeygrip(userInfo.fingerprint);
+      await gpg.configureAgent(gpg.agentConfig);
+      await gpg.presetPassphrase(keygrip, userInfo.passphrase).then(output => {
+        console.log(output);
+        expect(output).not.toEqual('');
       });
     });
   });
 
   describe('deleteKey', () => {
     it('removes key from GnuPG', async () => {
-      await importKey(userInfo.pgp);
-      await deleteKey(userInfo.fingerprint);
+      await gpg.importKey(userInfo.pgp);
+      await gpg.deleteKey(userInfo.fingerprint);
     });
   });
 });

__tests__/openpgp.test.ts

@@ -1,4 +1,4 @@
-import {readPrivateKey, generateKeyPair} from '../src/openpgp';
+import * as openpgp from '../src/openpgp';
 
 const userInfo = {
   name: 'Joe Tester',
@@ -118,7 +118,7 @@ PejgXO0uIRolYQ3sz2tMGhx1MfBqH64=
 describe('openpgp', () => {
   describe('readPrivateKey', () => {
     it('returns a PGP private key', async () => {
-      await readPrivateKey(userInfo.pgp).then(privateKey => {
+      await openpgp.readPrivateKey(userInfo.pgp).then(privateKey => {
         expect(privateKey.keyID).toEqual(userInfo.keyID);
         expect(privateKey.userID).toEqual(userInfo.userID);
         expect(privateKey.fingerprint).toEqual(userInfo.fingerprint);
@@ -128,7 +128,7 @@ describe('openpgp', () => {
 
   describe('generateKeyPair', () => {
     it('generates a PGP key pair', async () => {
-      await generateKeyPair(userInfo.name, userInfo.email, userInfo.passphrase).then(keyPair => {
+      await openpgp.generateKeyPair(userInfo.name, userInfo.email, userInfo.passphrase).then(keyPair => {
         expect(keyPair).not.toBeUndefined();
         expect(keyPair.publicKey).not.toBeUndefined();
         expect(keyPair.privateKey).not.toBeUndefined();

src/exec.ts

@@ -0,0 +1,34 @@
+import * as actionsExec from '@actions/exec';
+import {ExecOptions} from '@actions/exec';
+
+export interface ExecResult {
+  success: boolean;
+  stdout: string;
+  stderr: string;
+}
+
+export const exec = async (command: string, args: string[] = [], silent: boolean): Promise<ExecResult> => {
+  let stdout: string = '';
+  let stderr: string = '';
+
+  const options: ExecOptions = {
+    silent: silent,
+    ignoreReturnCode: true
+  };
+  options.listeners = {
+    stdout: (data: Buffer) => {
+      stdout += data.toString();
+    },
+    stderr: (data: Buffer) => {
+      stderr += data.toString();
+    }
+  };
+
+  const returnCode: number = await actionsExec.exec(command, args, options);
+
+  return {
+    success: returnCode === 0,
+    stdout: stdout.trim(),
+    stderr: stderr.trim()
+  };
+};

src/gpg.ts

@@ -1,27 +1,33 @@
-import * as child_process from 'child_process';
 import * as fs from 'fs';
 import * as path from 'path';
 import * as os from 'os';
+import * as exec from './exec';
+
+export const agentConfig = `default-cache-ttl 1
+max-cache-ttl 31536000
+allow-preset-passphrase`;
 
 export interface Version {
   gnupg: string;
   libgcrypt: string;
 }
 
-const gpg = async (args: string[] = []): Promise<string> => {
-  return child_process
-    .execSync(`gpg ${args.join(' ')}`, {
-      encoding: 'utf8'
-    })
-    .trim();
-};
+export interface Dirs {
+  libdir: string;
+  datadir: string;
+  homedir: string;
+}
 
 export const getVersion = async (): Promise<Version> => {
+  return await exec.exec('gpg', ['--version'], true).then(res => {
+    if (res.stderr != '') {
+      throw new Error(res.stderr);
+    }
+
     let gnupgVersion: string = '';
     let libgcryptVersion: string = '';
 
-  await gpg(['--version']).then(stdout => {
-    for (let line of stdout.replace(/\r/g, '').trim().split(/\n/g)) {
+    for (let line of res.stdout.replace(/\r/g, '').trim().split(/\n/g)) {
       if (line.startsWith('gpg (GnuPG) ')) {
         gnupgVersion = line.substr('gpg (GnuPG) '.length).trim();
       } else if (line.startsWith('gpg (GnuPG/MacGPG2) ')) {
@@ -30,25 +36,124 @@ export const getVersion = async (): Promise<Version> => {
         libgcryptVersion = line.substr('libgcrypt '.length).trim();
       }
     }
-  });
 
     return {
       gnupg: gnupgVersion,
       libgcrypt: libgcryptVersion
     };
+  });
 };
 
-export const importKey = async (armoredText: string): Promise<void> => {
+export const getDirs = async (): Promise<Dirs> => {
+  return await exec.exec('gpgconf', ['--list-dirs'], true).then(res => {
+    if (res.stderr != '' && !res.success) {
+      throw new Error(res.stderr);
+    }
+
+    let libdir: string = '';
+    let datadir: string = '';
+    let homedir: string = '';
+
+    for (let line of res.stdout.replace(/\r/g, '').trim().split(/\n/g)) {
+      if (line.startsWith('libdir:')) {
+        libdir = line.substr('libdir:'.length).replace('%3a', ':').trim();
+      } else if (line.startsWith('datadir:')) {
+        datadir = line.substr('datadir:'.length).replace('%3a', ':').trim();
+      } else if (line.startsWith('homedir:')) {
+        homedir = line.substr('homedir:'.length).replace('%3a', ':').trim();
+      }
+    }
+
+    return {
+      libdir: path.normalize(libdir),
+      datadir: path.normalize(datadir),
+      homedir: path.normalize(homedir)
+    };
+  });
+};
+
+export const importKey = async (armoredText: string): Promise<string> => {
   const keyFolder: string = fs.mkdtempSync(path.join(os.tmpdir(), 'ghaction-import-gpg-'));
   const keyPath: string = `${keyFolder}/key.pgp`;
   fs.writeFileSync(keyPath, armoredText, {mode: 0o600});
 
-  await gpg(['--import', '--batch', '--yes', keyPath]).finally(() => {
+  return await exec
+    .exec('gpg', ['--import', '--batch', '--yes', keyPath], true)
+    .then(res => {
+      if (res.stderr != '' && !res.success) {
+        throw new Error(res.stderr);
+      }
+      if (res.stderr != '') {
+        return res.stderr.trim();
+      }
+      return res.stdout.trim();
+    })
+    .finally(() => {
       fs.unlinkSync(keyPath);
     });
 };
 
-export const deleteKey = async (fingerprint: string): Promise<void> => {
-  await gpg(['--batch', '--yes', ' --delete-secret-keys', fingerprint]);
-  await gpg(['--batch', '--yes', ' --delete-keys', fingerprint]);
+export const getKeygrip = async (fingerprint: string): Promise<string> => {
+  return await exec
+    .exec('gpg', ['--batch', '--with-colons', '--with-keygrip', '--list-secret-keys', fingerprint], true)
+    .then(res => {
+      if (res.stderr != '' && !res.success) {
+        throw new Error(res.stderr);
+      }
+      let keygrip: string = '';
+      for (let line of res.stdout.replace(/\r/g, '').trim().split(/\n/g)) {
+        if (line.startsWith('grp')) {
+          keygrip = line.replace(/(grp|:)/g, '').trim();
+        }
+      }
+      return keygrip;
+    });
+};
+
+export const configureAgent = async (config: string): Promise<void> => {
+  const {homedir: homedir} = await getDirs();
+  const gpgAgentConf = path.join(homedir, 'gpg-agent.conf');
+  await fs.writeFile(gpgAgentConf, config, function (err) {
+    if (err) throw err;
+  });
+  await exec.exec(`gpg-connect-agent "RELOADAGENT" /bye`, [], true).then(res => {
+    if (res.stderr != '' && !res.success) {
+      throw new Error(res.stderr);
+    }
+  });
+};
+
+export const presetPassphrase = async (keygrip: string, passphrase: string): Promise<string> => {
+  await exec
+    .exec('gpg-preset-passphrase', ['--verbose', '--preset', '--passphrase', `"${passphrase}"`, keygrip], true)
+    .then(res => {
+      if (res.stderr != '' && !res.success) {
+        throw new Error(res.stderr);
+      }
+    });
+
+  return await exec.exec(`gpg-connect-agent "KEYINFO ${keygrip}" /bye`, [], true).then(res => {
+    if (res.stderr != '' && !res.success) {
+      throw new Error(res.stderr);
+    }
+    for (let line of res.stdout.replace(/\r/g, '').trim().split(/\n/g)) {
+      if (line.startsWith('ERR')) {
+        throw new Error(line);
+      }
+    }
+    return res.stdout.trim();
+  });
+};
+
+export const deleteKey = async (fingerprint: string): Promise<void> => {
+  await exec.exec('gpg', ['--batch', '--yes', '--delete-secret-keys', fingerprint], true).then(res => {
+    if (res.stderr != '' && !res.success) {
+      throw new Error(res.stderr);
+    }
+  });
+  await exec.exec('gpg', ['--batch', '--yes', '--delete-keys', fingerprint], true).then(res => {
+    if (res.stderr != '' && !res.success) {
+      throw new Error(res.stderr);
+    }
+  });
 };

src/main.ts

@@ -12,18 +12,37 @@ async function run(): Promise<void> {
 
     core.info('📣 GnuPG info');
     const version = await gpg.getVersion();
-    core.info(`GnuPG version: ${version.gnupg}`);
-    core.info(`libgcrypt version: ${version.libgcrypt}`);
+    const dirs = await gpg.getDirs();
+    core.info(`Version : ${version.gnupg} (libgcrypt ${version.libgcrypt})`);
+    core.info(`Homedir : ${dirs.homedir}`);
+    core.info(`Datadir : ${dirs.datadir}`);
+    core.info(`Libdir  : ${dirs.libdir}`);
 
     core.info('🔮 Checking signing key...');
     const privateKey = await openpgp.readPrivateKey(process.env.SIGNING_KEY);
-    core.debug(`key.fingerprint=${privateKey.fingerprint}`);
-    core.debug(`key.keyID=${privateKey.keyID}`);
-    core.debug(`key.userID=${privateKey.userID}`);
-    core.debug(`key.creationTime=${privateKey.creationTime}`);
+    core.debug(`Fingerprint  : ${privateKey.fingerprint}`);
+    core.debug(`KeyID        : ${privateKey.keyID}`);
+    core.debug(`UserID       : ${privateKey.userID}`);
+    core.debug(`CreationTime : ${privateKey.creationTime}`);
 
     core.info('🔑 Importing secret key...');
-    await gpg.importKey(process.env.SIGNING_KEY);
+    await gpg.importKey(process.env.SIGNING_KEY).then(stdout => {
+      core.debug(stdout);
+    });
+
+    if (process.env.PASSPHRASE) {
+      core.info('⚙️ Configuring GnuPG agent...');
+      await gpg.configureAgent(gpg.agentConfig);
+
+      core.info('📌 Getting keygrip...');
+      const keygrip = await gpg.getKeygrip(privateKey.fingerprint);
+      core.debug(`${keygrip}`);
+
+      core.info('🔓 Preset passphrase...');
+      await gpg.presetPassphrase(keygrip, process.env.PASSPHRASE).then(stdout => {
+        core.debug(stdout);
+      });
+    }
   } catch (error) {
     core.setFailed(error.message);
   }
@@ -31,11 +50,11 @@ async function run(): Promise<void> {
 
 async function cleanup(): Promise<void> {
   if (!process.env.SIGNING_KEY) {
-    core.debug('Private key is not defined. Skipping cleanup.');
+    core.debug('Signing key is not defined. Skipping cleanup.');
     return;
   }
   try {
-    core.info('🚿 Removing keys from GnuPG...');
+    core.info('🚿 Removing keys...');
     const privateKey = await openpgp.readPrivateKey(process.env.SIGNING_KEY);
     await gpg.deleteKey(privateKey.fingerprint);
   } catch (error) {