Stop adding GitHub SSH keys (#171)

We need to fix the SSH keys shipped with this action:
https://github.blog/2023-03-23-we-updated-our-rsa-ssh-host-key/

But, we have another issue
(https://github.com/webfactory/ssh-agent/pull/108) with regards to host
keys: On self-hosted runners which are not ephemeral the known_host file
fills up with repeated entries, because every action run adds a new line
with the same host keys.

Also, on those machines, the old key will still be in the `known_hosts`
file.

IMHO this action should not be repsonsible for shipping SSH host keys,
that's too much responsibility.

This section in the code is a leftover from early days when GitHub
provided runners did not include SSH keys at all. For a long time
already, GH takes care of placing their SSH keys in their runner images.

For self-hosted runners, those people setting up the runner should fetch
and verify SSH keys themselves and put it into the `known_hosts` file.

I know this is a breaking change and is going to annoy users. But on the
other hand, there is no better opportunity to drop this feature than
with an emergency-style key revocation as today.

Closes #106, closes #129, closes #169, closes #170, closes #172.

README.md

@@ -272,4 +272,4 @@ developer looking for new challenges, we'd like to hear from you!
 - <https://www.webfactory.de>
 - <https://twitter.com/webfactory>
 
-Copyright 2019 – 2022 webfactory GmbH, Bonn. Code released under [the MIT license](LICENSE).
+Copyright 2019 – 2023 webfactory GmbH, Bonn. Code released under [the MIT license](LICENSE).

dist/cleanup.js

@@ -292,13 +292,14 @@ var __importStar = (this && this.__importStar) || function (mod) {
     return result;
 };
 Object.defineProperty(exports, "__esModule", { value: true });
-exports.issueCommand = void 0;
+exports.prepareKeyValueMessage = exports.issueFileCommand = void 0;
 // We use any as a valid input type
 /* eslint-disable @typescript-eslint/no-explicit-any */
 const fs = __importStar(__webpack_require__(747));
 const os = __importStar(__webpack_require__(87));
+const uuid_1 = __webpack_require__(62);
 const utils_1 = __webpack_require__(82);
-function issueCommand(command, message) {
+function issueFileCommand(command, message) {
     const filePath = process.env[`GITHUB_${command}`];
     if (!filePath) {
         throw new Error(`Unable to find environment variable for file command ${command}`);
@@ -310,7 +311,22 @@ function issueCommand(command, message) {
         encoding: 'utf8'
     });
 }
-exports.issueCommand = issueCommand;
+exports.issueFileCommand = issueFileCommand;
+function prepareKeyValueMessage(key, value) {
+    const delimiter = `ghadelimiter_${uuid_1.v4()}`;
+    const convertedValue = utils_1.toCommandValue(value);
+    // These should realistically never happen, but just in case someone finds a
+    // way to exploit uuid generation let's not allow keys or values that contain
+    // the delimiter.
+    if (key.includes(delimiter)) {
+        throw new Error(`Unexpected input: name should not contain the delimiter "${delimiter}"`);
+    }
+    if (convertedValue.includes(delimiter)) {
+        throw new Error(`Unexpected input: value should not contain the delimiter "${delimiter}"`);
+    }
+    return `${key}<<${delimiter}${os.EOL}${convertedValue}${os.EOL}${delimiter}`;
+}
+exports.prepareKeyValueMessage = prepareKeyValueMessage;
 //# sourceMappingURL=file-command.js.map
 
 /***/ }),
@@ -1668,7 +1684,6 @@ const file_command_1 = __webpack_require__(102);
 const utils_1 = __webpack_require__(82);
 const os = __importStar(__webpack_require__(87));
 const path = __importStar(__webpack_require__(622));
-const uuid_1 = __webpack_require__(62);
 const oidc_utils_1 = __webpack_require__(742);
 /**
  * The code to exit an action
@@ -1698,20 +1713,9 @@ function exportVariable(name, val) {
     process.env[name] = convertedVal;
     const filePath = process.env['GITHUB_ENV'] || '';
     if (filePath) {
-        const delimiter = `ghadelimiter_${uuid_1.v4()}`;
+        return file_command_1.issueFileCommand('ENV', file_command_1.prepareKeyValueMessage(name, val));
-        // These should realistically never happen, but just in case someone finds a way to exploit uuid generation let's not allow keys or values that contain the delimiter.
-        if (name.includes(delimiter)) {
-            throw new Error(`Unexpected input: name should not contain the delimiter "${delimiter}"`);
     }
-        if (convertedVal.includes(delimiter)) {
-            throw new Error(`Unexpected input: value should not contain the delimiter "${delimiter}"`);
-        }
-        const commandValue = `${name}<<${delimiter}${os.EOL}${convertedVal}${os.EOL}${delimiter}`;
-        file_command_1.issueCommand('ENV', commandValue);
-    }
-    else {
     command_1.issueCommand('set-env', { name }, convertedVal);
-    }
 }
 exports.exportVariable = exportVariable;
 /**
@@ -1729,7 +1733,7 @@ exports.setSecret = setSecret;
 function addPath(inputPath) {
     const filePath = process.env['GITHUB_PATH'] || '';
     if (filePath) {
-        file_command_1.issueCommand('PATH', inputPath);
+        file_command_1.issueFileCommand('PATH', inputPath);
     }
     else {
         command_1.issueCommand('add-path', {}, inputPath);
@@ -1769,7 +1773,10 @@ function getMultilineInput(name, options) {
     const inputs = getInput(name, options)
         .split('\n')
         .filter(x => x !== '');
+    if (options && options.trimWhitespace === false) {
         return inputs;
+    }
+    return inputs.map(input => input.trim());
 }
 exports.getMultilineInput = getMultilineInput;
 /**
@@ -1802,8 +1809,12 @@ exports.getBooleanInput = getBooleanInput;
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 function setOutput(name, value) {
+    const filePath = process.env['GITHUB_OUTPUT'] || '';
+    if (filePath) {
+        return file_command_1.issueFileCommand('OUTPUT', file_command_1.prepareKeyValueMessage(name, value));
+    }
     process.stdout.write(os.EOL);
-    command_1.issueCommand('set-output', { name }, value);
+    command_1.issueCommand('set-output', { name }, utils_1.toCommandValue(value));
 }
 exports.setOutput = setOutput;
 /**
@@ -1932,7 +1943,11 @@ exports.group = group;
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 function saveState(name, value) {
-    command_1.issueCommand('save-state', { name }, value);
+    const filePath = process.env['GITHUB_STATE'] || '';
+    if (filePath) {
+        return file_command_1.issueFileCommand('STATE', file_command_1.prepareKeyValueMessage(name, value));
+    }
+    command_1.issueCommand('save-state', { name }, utils_1.toCommandValue(value));
 }
 exports.saveState = saveState;
 /**

dist/index.js

@@ -292,13 +292,14 @@ var __importStar = (this && this.__importStar) || function (mod) {
     return result;
 };
 Object.defineProperty(exports, "__esModule", { value: true });
-exports.issueCommand = void 0;
+exports.prepareKeyValueMessage = exports.issueFileCommand = void 0;
 // We use any as a valid input type
 /* eslint-disable @typescript-eslint/no-explicit-any */
 const fs = __importStar(__webpack_require__(747));
 const os = __importStar(__webpack_require__(87));
+const uuid_1 = __webpack_require__(62);
 const utils_1 = __webpack_require__(82);
-function issueCommand(command, message) {
+function issueFileCommand(command, message) {
     const filePath = process.env[`GITHUB_${command}`];
     if (!filePath) {
         throw new Error(`Unable to find environment variable for file command ${command}`);
@@ -310,7 +311,22 @@ function issueCommand(command, message) {
         encoding: 'utf8'
     });
 }
-exports.issueCommand = issueCommand;
+exports.issueFileCommand = issueFileCommand;
+function prepareKeyValueMessage(key, value) {
+    const delimiter = `ghadelimiter_${uuid_1.v4()}`;
+    const convertedValue = utils_1.toCommandValue(value);
+    // These should realistically never happen, but just in case someone finds a
+    // way to exploit uuid generation let's not allow keys or values that contain
+    // the delimiter.
+    if (key.includes(delimiter)) {
+        throw new Error(`Unexpected input: name should not contain the delimiter "${delimiter}"`);
+    }
+    if (convertedValue.includes(delimiter)) {
+        throw new Error(`Unexpected input: value should not contain the delimiter "${delimiter}"`);
+    }
+    return `${key}<<${delimiter}${os.EOL}${convertedValue}${os.EOL}${delimiter}`;
+}
+exports.prepareKeyValueMessage = prepareKeyValueMessage;
 //# sourceMappingURL=file-command.js.map
 
 /***/ }),
@@ -343,13 +359,7 @@ try {
     }
 
     const homeSsh = homePath + '/.ssh';
-
-    console.log(`Adding GitHub.com keys to ${homeSsh}/known_hosts`);
-
     fs.mkdirSync(homeSsh, { recursive: true });
-    fs.appendFileSync(`${homeSsh}/known_hosts`, '\ngithub.com ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBEmKSENjQEezOmxkZMy7opKgwFB9nkt5YRrYMjNuG5N87uRgg6CLrbo5wAdT/y6v0mKV0U2w0WZ2YB/++Tpockg=\n');
-    fs.appendFileSync(`${homeSsh}/known_hosts`, '\ngithub.com ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOMqqnkVzrm0SdG6UOoqKLsabgH5C9okWi0dh2l9GKJl\n');
-    fs.appendFileSync(`${homeSsh}/known_hosts`, '\ngithub.com ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq2A7hRGmdnm9tUDbO9IDSwBK6TbQa+PXYPCPy6rbTrTtw7PHkccKrpp0yVhp5HdEIcKr6pLlVDBfOLX9QUsyCOV0wzfjIJNlGEYsdlLJizHhbn2mUjvSAHQqZETYP81eFzLQNnPHt4EVVUh7VfDESU84KezmD5QlWpXLmvU31/yMf+Se8xhHTvKSCZIFImWwoG6mbUoWf9nzpIoaSjB+weqqUUmpaaasXVal72J+UX2B+2RPW3RcT0eOzQgqlJL3RKrTJvdsjE3JEAvGq3lGHSZXy28G3skua2SmVi/w4yCE6gbODqnTWlg7+wC604ydGXA8VJiS5ap43JXiUFFAaQ==\n');
 
     console.log("Starting ssh-agent");
 
@@ -1755,7 +1765,6 @@ const file_command_1 = __webpack_require__(102);
 const utils_1 = __webpack_require__(82);
 const os = __importStar(__webpack_require__(87));
 const path = __importStar(__webpack_require__(622));
-const uuid_1 = __webpack_require__(62);
 const oidc_utils_1 = __webpack_require__(742);
 /**
  * The code to exit an action
@@ -1785,20 +1794,9 @@ function exportVariable(name, val) {
     process.env[name] = convertedVal;
     const filePath = process.env['GITHUB_ENV'] || '';
     if (filePath) {
-        const delimiter = `ghadelimiter_${uuid_1.v4()}`;
+        return file_command_1.issueFileCommand('ENV', file_command_1.prepareKeyValueMessage(name, val));
-        // These should realistically never happen, but just in case someone finds a way to exploit uuid generation let's not allow keys or values that contain the delimiter.
-        if (name.includes(delimiter)) {
-            throw new Error(`Unexpected input: name should not contain the delimiter "${delimiter}"`);
     }
-        if (convertedVal.includes(delimiter)) {
-            throw new Error(`Unexpected input: value should not contain the delimiter "${delimiter}"`);
-        }
-        const commandValue = `${name}<<${delimiter}${os.EOL}${convertedVal}${os.EOL}${delimiter}`;
-        file_command_1.issueCommand('ENV', commandValue);
-    }
-    else {
     command_1.issueCommand('set-env', { name }, convertedVal);
-    }
 }
 exports.exportVariable = exportVariable;
 /**
@@ -1816,7 +1814,7 @@ exports.setSecret = setSecret;
 function addPath(inputPath) {
     const filePath = process.env['GITHUB_PATH'] || '';
     if (filePath) {
-        file_command_1.issueCommand('PATH', inputPath);
+        file_command_1.issueFileCommand('PATH', inputPath);
     }
     else {
         command_1.issueCommand('add-path', {}, inputPath);
@@ -1856,7 +1854,10 @@ function getMultilineInput(name, options) {
     const inputs = getInput(name, options)
         .split('\n')
         .filter(x => x !== '');
+    if (options && options.trimWhitespace === false) {
         return inputs;
+    }
+    return inputs.map(input => input.trim());
 }
 exports.getMultilineInput = getMultilineInput;
 /**
@@ -1889,8 +1890,12 @@ exports.getBooleanInput = getBooleanInput;
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 function setOutput(name, value) {
+    const filePath = process.env['GITHUB_OUTPUT'] || '';
+    if (filePath) {
+        return file_command_1.issueFileCommand('OUTPUT', file_command_1.prepareKeyValueMessage(name, value));
+    }
     process.stdout.write(os.EOL);
-    command_1.issueCommand('set-output', { name }, value);
+    command_1.issueCommand('set-output', { name }, utils_1.toCommandValue(value));
 }
 exports.setOutput = setOutput;
 /**
@@ -2019,7 +2024,11 @@ exports.group = group;
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 function saveState(name, value) {
-    command_1.issueCommand('save-state', { name }, value);
+    const filePath = process.env['GITHUB_STATE'] || '';
+    if (filePath) {
+        return file_command_1.issueFileCommand('STATE', file_command_1.prepareKeyValueMessage(name, value));
+    }
+    command_1.issueCommand('save-state', { name }, utils_1.toCommandValue(value));
 }
 exports.saveState = saveState;
 /**

index.js

@@ -23,13 +23,7 @@ try {
     }
 
     const homeSsh = homePath + '/.ssh';
-
-    console.log(`Adding GitHub.com keys to ${homeSsh}/known_hosts`);
-
     fs.mkdirSync(homeSsh, { recursive: true });
-    fs.appendFileSync(`${homeSsh}/known_hosts`, '\ngithub.com ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBEmKSENjQEezOmxkZMy7opKgwFB9nkt5YRrYMjNuG5N87uRgg6CLrbo5wAdT/y6v0mKV0U2w0WZ2YB/++Tpockg=\n');
-    fs.appendFileSync(`${homeSsh}/known_hosts`, '\ngithub.com ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOMqqnkVzrm0SdG6UOoqKLsabgH5C9okWi0dh2l9GKJl\n');
-    fs.appendFileSync(`${homeSsh}/known_hosts`, '\ngithub.com ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq2A7hRGmdnm9tUDbO9IDSwBK6TbQa+PXYPCPy6rbTrTtw7PHkccKrpp0yVhp5HdEIcKr6pLlVDBfOLX9QUsyCOV0wzfjIJNlGEYsdlLJizHhbn2mUjvSAHQqZETYP81eFzLQNnPHt4EVVUh7VfDESU84KezmD5QlWpXLmvU31/yMf+Se8xhHTvKSCZIFImWwoG6mbUoWf9nzpIoaSjB+weqqUUmpaaasXVal72J+UX2B+2RPW3RcT0eOzQgqlJL3RKrTJvdsjE3JEAvGq3lGHSZXy28G3skua2SmVi/w4yCE6gbODqnTWlg7+wC604ydGXA8VJiS5ap43JXiUFFAaQ==\n');
 
     console.log("Starting ssh-agent");