actions/ssh-agent
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Randomize SSH auth socket, kill agent to support non-ephemeral, self hosted runners (@thommyhh, #27)

Browse source 
Thanks to @thommyhh for this contribution!

Unless the `SSH_AUTH_SOCK` is configured explicitly, this change will make the SSH agent use a random file name for the socket. That way, multiple, concurrent SSH agents can be used on non-ephemeral, self-hosted runners.

A new post-action step will automatically clean up the running agent at the end of a job.

Be aware of the possible security implications: Two jobs running on the same runner might be able to access each other's socket and thus access repositories and/or hosts.
This commit is contained in:
Thorben Nissen 2020-05-18 09:08:29 +02:00 committed by GitHub
parent a82ae3cd1a
commit 4fcb25e7ef
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
9 changed files with 424 additions and 20 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
README.md
View file

@ -57,6 +57,11 @@ The `ssh-agent` will load all of the keys and try each one in order when establi
There's one **caveat**, though: SSH servers may abort the connection attempt after a number of mismatching keys have been presented. So if, for example, you have
six different keys loaded into the `ssh-agent`, but the server aborts after five unknown keys, the last key (which might be the right one) will never even be tried.
## Exported variables
The action exports `SSH_AUTH_SOCK` and `SSH_AGENT_PID` through the Github Actions core module.
The `$SSH_AUTH_SOCK` is used by several applications like git or rsync to connect to the SSH authentication agent.
The `$SSH_AGENT_PID` contains the process id of the agent. This is used to kill the agent in post job action.
## Known issues and limitations
### Currently OS X and Linux only
@ -116,7 +121,7 @@ As a note to my future self, in order to work on this repo:
* Run `npm install` to fetch dependencies
* _hack hack hack_
* `node index.js`. Inputs are passed through `INPUT_` env vars with their names uppercased. Use `env "INPUT_SSH-PRIVATE-KEY=\`cat file\`" node index.js` for this action.
* Run `./node_modules/.bin/ncc build index.js` to update `dist/index.js`, which is the file actually run
* Run `npm run build` to update `dist/*`, which holds the files actually run
* Read https://help.github.com/en/articles/creating-a-javascript-action if unsure.
* Maybe update the README example when publishing a new version.

2
action.yml
View file

@ -6,10 +6,10 @@ inputs:
required: true
ssh-auth-sock:
description: 'Where to place the SSH Agent auth socket'
default: /tmp/ssh-auth.sock
runs:
using: 'node12'
main: 'dist/index.js'
post: 'dist/cleanup.js'
branding:
icon: loader
color: 'yellow'

10
cleanup.js Normal file
View file

@ -0,0 +1,10 @@
const core = require('@actions/core')
const { execSync } = require('child_process')
try {
// Kill the started SSH agent
console.log('Stopping SSH agent')
execSync('kill ${SSH_AGENT_PID}', { stdio: 'inherit' })
} catch (error) {
core.setFailed(error.message)
}

332
dist/cleanup.js vendored Normal file
View file

@ -0,0 +1,332 @@
module.exports =
/******/ (function(modules, runtime) { // webpackBootstrap
/******/ "use strict";
/******/ // The module cache
/******/ var installedModules = {};
/******/
/******/ // The require function
/******/ function __webpack_require__(moduleId) {
/******/
/******/ // Check if module is in cache
/******/ if(installedModules[moduleId]) {
/******/ return installedModules[moduleId].exports;
/******/ }
/******/ // Create a new module (and put it into the cache)
/******/ var module = installedModules[moduleId] = {
/******/ i: moduleId,
/******/ l: false,
/******/ exports: {}
/******/ };
/******/
/******/ // Execute the module function
/******/ modules[moduleId].call(module.exports, module, module.exports, __webpack_require__);
/******/
/******/ // Flag the module as loaded
/******/ module.l = true;
/******/
/******/ // Return the exports of the module
/******/ return module.exports;
/******/ }
/******/
/******/
/******/ __webpack_require__.ab = __dirname + "/";
/******/
/******/ // the startup function
/******/ function startup() {
/******/ // Load entry module and return exports
/******/ return __webpack_require__(175);
/******/ };
/******/
/******/ // run startup
/******/ return startup();
/******/ })
/************************************************************************/
/******/ ({
/***/ 87:
/***/ (function(module) {
module.exports = require("os");
/***/ }),
/***/ 129:
/***/ (function(module) {
module.exports = require("child_process");
/***/ }),
/***/ 175:
/***/ (function(__unusedmodule, __unusedexports, __webpack_require__) {
const core = __webpack_require__(470)
const { execSync } = __webpack_require__(129)
try {
// Kill the started SSH agent
console.log('Stopping SSH agent')
execSync('kill ${SSH_AGENT_PID}', { stdio: 'inherit' })
} catch (error) {
core.setFailed(error.message)
}
/***/ }),
/***/ 431:
/***/ (function(__unusedmodule, exports, __webpack_require__) {
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
const os = __webpack_require__(87);
/**
* Commands
*
* Command Format:
* ##[name key=value;key=value]message
*
* Examples:
* ##[warning]This is the user warning message
* ##[set-secret name=mypassword]definitelyNotAPassword!
*/
function issueCommand(command, properties, message) {
const cmd = new Command(command, properties, message);
process.stdout.write(cmd.toString() + os.EOL);
}
exports.issueCommand = issueCommand;
function issue(name, message = '') {
issueCommand(name, {}, message);
}
exports.issue = issue;
const CMD_PREFIX = '##[';
class Command {
constructor(command, properties, message) {
if (!command) {
command = 'missing.command';
}
this.command = command;
this.properties = properties;
this.message = message;
}
toString() {
let cmdStr = CMD_PREFIX + this.command;
if (this.properties && Object.keys(this.properties).length > 0) {
cmdStr += ' ';
for (const key in this.properties) {
if (this.properties.hasOwnProperty(key)) {
const val = this.properties[key];
if (val) {
// safely append the val - avoid blowing up when attempting to
// call .replace() if message is not a string for some reason
cmdStr += `${key}=${escape(`${val || ''}`)};`;
}
}
}
}
cmdStr += ']';
// safely append the message - avoid blowing up when attempting to
// call .replace() if message is not a string for some reason
const message = `${this.message || ''}`;
cmdStr += escapeData(message);
return cmdStr;
}
}
function escapeData(s) {
return s.replace(/\r/g, '%0D').replace(/\n/g, '%0A');
}
function escape(s) {
return s
.replace(/\r/g, '%0D')
.replace(/\n/g, '%0A')
.replace(/]/g, '%5D')
.replace(/;/g, '%3B');
}
//# sourceMappingURL=command.js.map
/***/ }),
/***/ 470:
/***/ (function(__unusedmodule, exports, __webpack_require__) {
"use strict";
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
Object.defineProperty(exports, "__esModule", { value: true });
const command_1 = __webpack_require__(431);
const path = __webpack_require__(622);
/**
* The code to exit an action
*/
var ExitCode;
(function (ExitCode) {
/**
* A code indicating that the action was successful
*/
ExitCode[ExitCode["Success"] = 0] = "Success";
/**
* A code indicating that the action was a failure
*/
ExitCode[ExitCode["Failure"] = 1] = "Failure";
})(ExitCode = exports.ExitCode || (exports.ExitCode = {}));
//-----------------------------------------------------------------------
// Variables
//-----------------------------------------------------------------------
/**
* sets env variable for this action and future actions in the job
* @param name the name of the variable to set
* @param val the value of the variable
*/
function exportVariable(name, val) {
process.env[name] = val;
command_1.issueCommand('set-env', { name }, val);
}
exports.exportVariable = exportVariable;
/**
* exports the variable and registers a secret which will get masked from logs
* @param name the name of the variable to set
* @param val value of the secret
*/
function exportSecret(name, val) {
exportVariable(name, val);
// the runner will error with not implemented
// leaving the function but raising the error earlier
command_1.issueCommand('set-secret', {}, val);
throw new Error('Not implemented.');
}
exports.exportSecret = exportSecret;
/**
* Prepends inputPath to the PATH (for this action and future actions)
* @param inputPath
*/
function addPath(inputPath) {
command_1.issueCommand('add-path', {}, inputPath);
process.env['PATH'] = `${inputPath}${path.delimiter}${process.env['PATH']}`;
}
exports.addPath = addPath;
/**
* Gets the value of an input. The value is also trimmed.
*
* @param name name of the input to get
* @param options optional. See InputOptions.
* @returns string
*/
function getInput(name, options) {
const val = process.env[`INPUT_${name.replace(' ', '_').toUpperCase()}`] || '';
if (options && options.required && !val) {
throw new Error(`Input required and not supplied: ${name}`);
}
return val.trim();
}
exports.getInput = getInput;
/**
* Sets the value of an output.
*
* @param name name of the output to set
* @param value value to store
*/
function setOutput(name, value) {
command_1.issueCommand('set-output', { name }, value);
}
exports.setOutput = setOutput;
//-----------------------------------------------------------------------
// Results
//-----------------------------------------------------------------------
/**
* Sets the action status to failed.
* When the action exits it will be with an exit code of 1
* @param message add error issue message
*/
function setFailed(message) {
process.exitCode = ExitCode.Failure;
error(message);
}
exports.setFailed = setFailed;
//-----------------------------------------------------------------------
// Logging Commands
//-----------------------------------------------------------------------
/**
* Writes debug message to user log
* @param message debug message
*/
function debug(message) {
command_1.issueCommand('debug', {}, message);
}
exports.debug = debug;
/**
* Adds an error issue
* @param message error issue message
*/
function error(message) {
command_1.issue('error', message);
}
exports.error = error;
/**
* Adds an warning issue
* @param message warning issue message
*/
function warning(message) {
command_1.issue('warning', message);
}
exports.warning = warning;
/**
* Begin an output group.
*
* Output until the next `groupEnd` will be foldable in this group
*
* @param name The name of the output group
*/
function startGroup(name) {
command_1.issue('group', name);
}
exports.startGroup = startGroup;
/**
* End an output group.
*/
function endGroup() {
command_1.issue('endgroup');
}
exports.endGroup = endGroup;
/**
* Wrap an asynchronous function call in a group.
*
* Returns the same type as the function itself.
*
* @param name The name of the group
* @param fn The function to wrap in the group
*/
function group(name, fn) {
return __awaiter(this, void 0, void 0, function* () {
startGroup(name);
let result;
try {
result = yield fn();
}
finally {
endGroup();
}
return result;
});
}
exports.group = group;
//# sourceMappingURL=core.js.map
/***/ }),
/***/ 622:
/***/ (function(module) {
module.exports = require("path");
/***/ })
/******/ });

19
dist/index.js vendored
View file

@ -62,7 +62,7 @@ try {
const home = process.env['HOME'];
const homeSsh = home + '/.ssh';
const privateKey = core.getInput('ssh-private-key').trim();
const privateKey = core.getInput('ssh-private-key');
if (!privateKey) {
core.setFailed("The ssh-private-key argument is empty. Maybe the secret has not been configured, or you are using a wrong secret name in your workflow file.");
@ -77,8 +77,21 @@ try {
console.log("Starting ssh-agent");
const authSock = core.getInput('ssh-auth-sock');
child_process.execFileSync('ssh-agent', ['-a', authSock]);
core.exportVariable('SSH_AUTH_SOCK', authSock);
let sshAgentOutput = ''
if (authSock && authSock.length > 0) {
sshAgentOutput = child_process.execFileSync('ssh-agent', ['-a', authSock]);
} else {
sshAgentOutput = child_process.execFileSync('ssh-agent')
}
// Extract auth socket path and agent pid and set them as job variables
const lines = sshAgentOutput.toString().split("\n")
for (const lineNumber in lines) {
const matches = /^(SSH_AUTH_SOCK|SSH_AGENT_PID)=(.*); export \1/.exec(lines[lineNumber])
if (matches && matches.length > 0) {
core.exportVariable(matches[1], matches[2])
}
}
console.log("Adding private key to agent");
privateKey.split(/(?=-----BEGIN)/).forEach(function(key) {

17
index.js
View file

@ -22,8 +22,21 @@ try {
console.log("Starting ssh-agent");
const authSock = core.getInput('ssh-auth-sock');
child_process.execFileSync('ssh-agent', ['-a', authSock]);
core.exportVariable('SSH_AUTH_SOCK', authSock);
let sshAgentOutput = ''
if (authSock && authSock.length > 0) {
sshAgentOutput = child_process.execFileSync('ssh-agent', ['-a', authSock]);
} else {
sshAgentOutput = child_process.execFileSync('ssh-agent')
}
// Extract auth socket path and agent pid and set them as job variables
const lines = sshAgentOutput.toString().split("\n")
for (const lineNumber in lines) {
const matches = /^(SSH_AUTH_SOCK|SSH_AGENT_PID)=(.*); export \1/.exec(lines[lineNumber])
if (matches && matches.length > 0) {
core.exportVariable(matches[1], matches[2])
}
}
console.log("Adding private key to agent");
privateKey.split(/(?=-----BEGIN)/).forEach(function(key) {

12
package-lock.json generated
View file

@ -5,9 +5,9 @@
"requires": true,
"dependencies": {
"@actions/core": {
"version": "1.1.0",
"resolved": "https://registry.npmjs.org/@actions/core/-/core-1.1.0.tgz",
"integrity": "sha512-KKpo3xzo0Zsikni9tbOsEQkxZBGDsYSJZNkTvmo0gPSXrc98TBOcdTvKwwjitjkjHkreTggWdB1ACiAFVgsuzA==",
"version": "1.2.4",
"resolved": "https://registry.npmjs.org/@actions/core/-/core-1.2.4.tgz",
"integrity": "sha512-YJCEq8BE3CdN8+7HPZ/4DxJjk/OkZV2FFIf+DlZTC/4iBlzYCD5yjRR6eiOS5llO11zbRltIRuKAjMKaWTE6cg==",
"dev": true
},
"@zeit/ncc": {
@ -15,12 +15,6 @@
"resolved": "https://registry.npmjs.org/@zeit/ncc/-/ncc-0.20.5.tgz",
"integrity": "sha512-XU6uzwvv95DqxciQx+aOLhbyBx/13ky+RK1y88Age9Du3BlA4mMPCy13BGjayOrrumOzlq1XV3SD/BWiZENXlw==",
"dev": true
},
"child_process": {
"version": "1.0.2",
"resolved": "https://registry.npmjs.org/child_process/-/child_process-1.0.2.tgz",
"integrity": "sha1-sffn/HPSXn/R1FWtyU4UODAYK1o=",
"dev": true
}
}
}

8
package.json
View file

@ -7,8 +7,10 @@
"author": "webfactory GmbH <info@webfactory.de>",
"license": "MIT",
"devDependencies": {
"@actions/core": "^1.1.0",
"@zeit/ncc": "^0.20.5",
"child_process": "^1.0.2"
"@actions/core": "^1.2.4",
"@zeit/ncc": "^0.20.5"
},
"scripts": {
"build": "node scripts/build.js"
}
}

35
scripts/build.js Normal file
View file

@ -0,0 +1,35 @@
const { execSync } = require('child_process')
const path = require('path')
const fs = require('fs')
const buildDir = path.join(process.cwd(), 'build')
const distDir = path.join(process.cwd(), 'dist')
const buildIndexJs = path.join(buildDir, 'index.js')
const distIndexJs = path.join(distDir, 'index.js')
const distCleanupJs = path.join(distDir, 'cleanup.js')
if (!fs.existsSync(buildDir)) {
fs.mkdirSync(buildDir)
}
// Build the main index.js file
console.log('Building index.js...')
execSync(`./node_modules/.bin/ncc build index.js -q -o ${buildDir}`)
if (fs.existsSync(distIndexJs)) {
fs.unlinkSync(distIndexJs)
}
fs.renameSync(buildIndexJs, distIndexJs)
// Build the cleanup.js file
console.log('Building cleanup.js...')
execSync(`./node_modules/.bin/ncc build cleanup.js -q -o ${buildDir}`)
if (fs.existsSync(distCleanupJs)) {
fs.unlinkSync(distCleanupJs)
}
fs.renameSync(buildIndexJs, distCleanupJs)
console.log('Cleaning up...')
fs.rmdirSync(buildDir)
console.log('Done')