564 lines
17 KiB
JavaScript
564 lines
17 KiB
JavaScript
// server
|
|
// app/socket.js
|
|
"use strict"
|
|
|
|
const createDebug = require("debug")
|
|
const { header } = require("./config")
|
|
const debug = createDebug("webssh2:socket")
|
|
const SSH = require("ssh2").Client
|
|
const { sanitizeObject } = require("./utils")
|
|
const session = require("express-session")
|
|
|
|
/**
|
|
* Handles WebSocket connections for SSH
|
|
* @param {import('socket.io').Server} io - The Socket.IO server instance
|
|
* @param {Object} config - The configuration object
|
|
*/
|
|
module.exports = function (io, config) {
|
|
io.on("connection", (socket) => handleConnection(socket, config))
|
|
}
|
|
|
|
/**
|
|
* Handles a new WebSocket connection
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {Object} config - The configuration object
|
|
*/
|
|
function handleConnection(socket, config) {
|
|
let conn = null
|
|
let stream = null
|
|
let sessionState = {
|
|
connected: false,
|
|
authenticated: false,
|
|
host: null,
|
|
port: null,
|
|
username: null,
|
|
password: null,
|
|
term: null,
|
|
cols: null,
|
|
rows: null,
|
|
config: config
|
|
}
|
|
|
|
debug(`handleConnection: ${socket.id}, URL: ${socket.handshake.url}`)
|
|
|
|
// removeExistingListeners(socket)
|
|
setupInitialSocketListeners(socket, sessionState)
|
|
|
|
// Check for HTTP Basic Auth credentials
|
|
if (socket.handshake.session.sshCredentials) {
|
|
const creds = socket.handshake.session.sshCredentials
|
|
|
|
debug(
|
|
`handleConnection: creds from session: ${socket.id}, Host: ${creds.host}:`,
|
|
sanitizeObject(creds)
|
|
)
|
|
|
|
handleAuthenticate(socket, creds)
|
|
return
|
|
}
|
|
|
|
// Emit an event to the client to request authentication
|
|
const authenticated = sessionState.authenticated
|
|
if (!authenticated) {
|
|
debug(
|
|
`Requesting authentication for ${socket.id} and authenticated is ${authenticated}`
|
|
)
|
|
socket.emit("authentication", { action: "request_auth" })
|
|
}
|
|
|
|
/**
|
|
* Sets up initial socket event listeners
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {Object} config - The configuration object
|
|
*/
|
|
function setupInitialSocketListeners(socket, sessionState) {
|
|
config = sessionState.config
|
|
socket.on("error", (error) =>
|
|
console.error(`Socket error for ${socket.id}:`, error)
|
|
)
|
|
socket.on("authenticate", (creds) =>
|
|
handleAuthenticate(socket, creds, sessionState)
|
|
)
|
|
socket.on("disconnect", (reason) => {
|
|
debug(`Client ${socket.id} disconnected. Reason: ${reason}`)
|
|
debug("Socket state at disconnect:", socket.conn.transport.readyState)
|
|
if (conn) {
|
|
conn.end()
|
|
conn = null
|
|
}
|
|
if (stream) {
|
|
stream.end()
|
|
stream = null
|
|
}
|
|
})
|
|
}
|
|
|
|
/**
|
|
* Handles authentication attempts
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
*
|
|
* @param {Credentials} creds - The credentials for authentication
|
|
* @param {Object} config - The configuration object
|
|
*/
|
|
function handleAuthenticate(socket, creds) {
|
|
const config = sessionState.config
|
|
// {
|
|
// "host": "192.168.0.20",
|
|
// "port": 22,
|
|
// "username": "test123",
|
|
// "password": "Seven888!",
|
|
// "term": "xterm-color",
|
|
// "readyTimeout": 20000,
|
|
// "cursorBlink": "true",
|
|
// "cols": 151,
|
|
// "rows": 53
|
|
// }
|
|
debug("handleAuthenticate: ", JSON.stringify(sanitizeObject(creds)))
|
|
|
|
if (isValidCredentials(socket, creds)) {
|
|
creds.term !== null && (sessionState.term = creds.term)
|
|
initializeConnection(socket, creds)
|
|
return
|
|
}
|
|
|
|
// Handle invalid credentials scenario
|
|
debug(`CREDENTIALS INVALID: ${socket.id}, Host: ${creds.host}`)
|
|
socket.emit("authentication", {
|
|
success: false,
|
|
message: "Invalid credentials format"
|
|
})
|
|
}
|
|
|
|
/**
|
|
* Initializes an SSH connection
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {Credentials} creds - The user credentials
|
|
* @param {Object} config - The configuration object
|
|
*/
|
|
function initializeConnection(socket, creds) {
|
|
const config = sessionState.config
|
|
debug(
|
|
`initializeConnection: INITIALIZING SSH CONNECTION: ${socket.id}, Host: ${creds.host}`
|
|
)
|
|
if (conn) {
|
|
conn.end()
|
|
}
|
|
|
|
conn = new SSH()
|
|
socket.on("terminal", (data) => handleTerminal(socket, stream, data))
|
|
socket.emit("getTerminal", true)
|
|
|
|
conn.connect(getSSHConfig(creds, config))
|
|
|
|
conn.on("ready", () => {
|
|
sessionState.authenticated = true
|
|
sessionState.connected = true
|
|
sessionState.username = creds.username
|
|
sessionState.password = creds.password
|
|
sessionState.host = creds.host
|
|
sessionState.port = creds.port
|
|
debug(
|
|
`initializeConnection conn.on ready: ${socket.id}, Host: ${creds.host}`
|
|
)
|
|
socket.emit("authentication", { action: "auth_result", success: true })
|
|
|
|
// Emit consolidated permissions
|
|
socket.emit("permissions", {
|
|
allowReplay: config.options.allowReplay || false,
|
|
allowReauth: config.options.allowReauth || false
|
|
})
|
|
|
|
updateElement(socket, "footer", `ssh://${creds.host}:${creds.port}`)
|
|
|
|
if (config.header && config.header.text !== null) {
|
|
debug(`initializeConnection header: ${config.header}`)
|
|
updateElement(socket, "header", config.header.text)
|
|
}
|
|
debug(`initializeConnection: ${socket.id}, sessionState: ${JSON.stringify(sanitizeObject(sessionState))}`)
|
|
|
|
setupSSHListeners(socket)
|
|
initializeShell(socket)
|
|
})
|
|
|
|
conn.on("error", (err) => {
|
|
console.error(
|
|
`initializeConnection: SSH CONNECTION ERROR: ${socket.id}, Host: ${creds.host}, Error: ${err.message}`
|
|
)
|
|
if (err.level === "client-authentication") {
|
|
socket.emit("authentication", {
|
|
action: "auth_result",
|
|
success: false,
|
|
message: "Authentication failed"
|
|
})
|
|
} else {
|
|
handleError(socket, "SSH CONNECTION ERROR", err)
|
|
}
|
|
})
|
|
}
|
|
|
|
/**
|
|
* Sets up SSH-specific event listeners
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {Credentials} creds - The user credentials
|
|
*/
|
|
function setupSSHListeners(socket) {
|
|
conn.on("banner", (data) => handleBanner(socket, data))
|
|
conn.on("end", () => handleSSHEnd(socket))
|
|
conn.on("close", () => handleSSHClose(socket))
|
|
|
|
socket.on("data", (data) => handleSocketData(socket, stream, data))
|
|
socket.on("resize", (data) => handleResize(stream, data))
|
|
socket.on("control", (data) => handleControl(socket, stream, data))
|
|
}
|
|
|
|
/**
|
|
* Initializes the SSH shell
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {Credentials} creds - The user credentials
|
|
*/
|
|
function initializeShell(socket) {
|
|
debug(`initializeShell: INITIALIZING SHELL: ${socket.id}`)
|
|
debug(`initializeShell: sessionState: ${JSON.stringify(sanitizeObject(sessionState))}`)
|
|
const { term, cols, rows } = sessionState
|
|
|
|
conn.shell(
|
|
{
|
|
term: term,
|
|
cols: cols,
|
|
rows: rows
|
|
},
|
|
(err, str) => {
|
|
if (err) {
|
|
return handleError(socket, "EXEC ERROR", err)
|
|
}
|
|
stream = str
|
|
|
|
setupStreamListeners(stream, socket)
|
|
}
|
|
)
|
|
}
|
|
|
|
/**
|
|
* Sets up listeners for a stream.
|
|
*
|
|
* @param {Stream} stream - The stream object to listen to.
|
|
* @param {Socket} socket - The socket object associated with the stream.
|
|
*/
|
|
function setupStreamListeners(stream, socket) {
|
|
debug(`setupStreamListeners: ${socket.id}`)
|
|
stream.on("data", (data) => handleStreamData(socket, stream, data))
|
|
stream.on("close", (code, signal) =>
|
|
handleStreamClose(stream, socket, code, signal)
|
|
)
|
|
stream.stderr.on("data", (data) => debug("STDERR: " + data))
|
|
}
|
|
|
|
/**
|
|
* Handles the close event of a stream.
|
|
*
|
|
* @param {Stream} stream - The stream object.
|
|
* @param {Socket} socket - The socket object.
|
|
* @param {number} code - The code associated with the close event.
|
|
* @param {string} signal - The signal associated with the close event.
|
|
*/
|
|
function handleStreamClose(stream, socket, code, signal) {
|
|
debug(`handleStreamClose: STREAM CLOSE: ${socket.id}`)
|
|
handleError(socket, "STREAM CLOSE", {
|
|
message: code || signal ? `CODE: ${code} SIGNAL: ${signal}` : undefined
|
|
})
|
|
}
|
|
|
|
/**
|
|
* Handles the stream data received from the socket.
|
|
*
|
|
* @param {Socket} socket - The socket object.
|
|
* @param {Stream} stream - The stream object.
|
|
* @param {Buffer} data - The data received from the stream.
|
|
* @returns {void}
|
|
*/
|
|
function handleStreamData(socket, stream, data) {
|
|
const connected = sessionState.connected
|
|
socket.emit("data", data.toString("utf-8"))
|
|
if (socket && connected) {
|
|
try {
|
|
socket.write(data)
|
|
} catch (error) {
|
|
console.error(
|
|
"handleStreamData: Error writing to socket:",
|
|
error.message
|
|
)
|
|
// todo: close stream like in handleSocketData?
|
|
}
|
|
return
|
|
}
|
|
console.warn("handleStreamData: Attempted to write to closed socket")
|
|
}
|
|
|
|
/**
|
|
* Handles the 'banner' event of the SSH connection
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {string} data - The banner data
|
|
*/
|
|
function handleBanner(socket, data) {
|
|
// todo: sanatize the data
|
|
socket.emit("data", data.replace(/\r?\n/g, "\r\n"))
|
|
}
|
|
|
|
/**
|
|
* Handles the SSH connection end event
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
*/
|
|
function handleSSHEnd(socket) {
|
|
debug(`handleSSHEnd: SSH CONNECTION ENDED: ${socket.id}`)
|
|
handleConnectionClose(socket)
|
|
}
|
|
|
|
/**
|
|
* Handles the SSH connection close event
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
*/
|
|
function handleSSHClose(socket) {
|
|
debug(`handleSSHClose: SSH CONNECTION CLOSED: ${socket.id}`)
|
|
handleConnectionClose(socket)
|
|
}
|
|
|
|
/**
|
|
* Handles the closure of the SSH connection
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
*/
|
|
function handleConnectionClose(socket) {
|
|
debug(`handleConnectionClose: Closing connection for ${socket.id}`)
|
|
sessionState.connected = false
|
|
if (stream) {
|
|
stream.end()
|
|
stream = null
|
|
}
|
|
if (conn) {
|
|
conn.end()
|
|
conn = null
|
|
}
|
|
socket.emit("connection_closed")
|
|
}
|
|
|
|
/**
|
|
* Handles socket disconnection
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {string} reason - The reason for disconnection
|
|
*/
|
|
function handleDisconnect(socket, reason) {
|
|
debug(`DISCONNECT: ${socket.id}, Reason: ${reason}`)
|
|
handleConnectionClose(socket)
|
|
}
|
|
|
|
/**
|
|
* Handles incoming data from the client
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {import('ssh2').Channel} stream - The SSH stream
|
|
* @param {string} data - The incoming data
|
|
*/
|
|
function handleSocketData(socket, stream, data) {
|
|
const connected = sessionState.connected
|
|
if (stream && connected) {
|
|
try {
|
|
stream.write(data)
|
|
} catch (error) {
|
|
console.error(
|
|
"handleSocketData: Error writing to stream:",
|
|
error.message
|
|
)
|
|
handleConnectionClose(socket)
|
|
}
|
|
return
|
|
}
|
|
console.warn("handleSocketData: Attempted to write to closed stream")
|
|
socket.emit("connection_closed")
|
|
}
|
|
|
|
/**
|
|
* Handles terminal resize events
|
|
* @param {import('ssh2').Channel} stream - The SSH stream
|
|
* @param {Object} data - The resize data
|
|
* @param {number} data.rows - The number of rows
|
|
* @param {number} data.cols - The number of columns
|
|
*/
|
|
function handleResize(stream, data) {
|
|
const { rows, cols } = data
|
|
if (stream) {
|
|
debug(`Resizing terminal to ${rows}x${cols}`)
|
|
sessionState.rows = rows
|
|
sessionState.cols = cols
|
|
stream.setWindow(rows, cols)
|
|
return
|
|
}
|
|
console.warn("handleResize: Attempted to resize closed connection")
|
|
}
|
|
|
|
/**
|
|
* Handles control commands from the client
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {import('ssh2').Channel} stream - The SSH stream
|
|
* @param {string} data - The control command
|
|
*/
|
|
function handleControl(socket, stream, data) {
|
|
debug(`handleControl: Received control data: ${data}`)
|
|
if (data === "replayCredentials" && stream) {
|
|
replayCredentials(socket, stream)
|
|
} else if (data === "reauth") {
|
|
handleReauth(socket)
|
|
}
|
|
}
|
|
|
|
function handleTerminal(socket, conn, data) {
|
|
debug(`handleTerminal: Received terminal data: ${JSON.stringify(data)}`)
|
|
const { term, rows, cols } = data
|
|
if (term != null) {
|
|
sessionState.term = term;
|
|
}
|
|
sessionState.rows = rows
|
|
sessionState.cols = cols
|
|
}
|
|
|
|
/**
|
|
* Replays the user credentials to the SSH stream
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {import('ssh2').Channel} stream - The SSH stream
|
|
* @param {Credentials} credentials - The user credentials
|
|
* @param {Object} config - The configuration object
|
|
*/
|
|
function replayCredentials(socket, stream) {
|
|
const password = sessionState.password
|
|
const allowReplay = sessionState.config.options.allowReplay || false
|
|
|
|
if (allowReplay) {
|
|
debug(`replayCredentials: Replaying credentials for ${socket.id}`)
|
|
stream.write(password + "\n")
|
|
} else {
|
|
// todo: add a warning message to the client
|
|
console.warn(
|
|
`replayCredentials: Credential replay not allowed for ${socket.id}`
|
|
)
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Handles reauthentication request
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
*/
|
|
function handleReauth(socket) {
|
|
debug(`handleReauth: Reauthentication requested for ${socket.id}`)
|
|
if (config.options.allowReauth) {
|
|
clearSessionCredentials(socket)
|
|
debug(`handleReauth: Reauthenticating ${socket.id}`)
|
|
socket.emit("authentication", { action: "reauth" })
|
|
handleConnectionClose(socket)
|
|
} else {
|
|
// todo: add a warning message to the client
|
|
console.warn(
|
|
`handleReauth: Reauthentication not allowed for ${socket.id}`
|
|
)
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Handles SSH errors
|
|
* @param {import('socket.io').Socket} socket - The Socket.IO socket
|
|
* @param {string} context - The context where the error occurred
|
|
* @param {Error} [err] - The error object
|
|
*/
|
|
function handleError(socket, context, err) {
|
|
const errorMessage = err ? `: ${err.message}` : ""
|
|
debug(`WebSSH2 error: ${context}${errorMessage}`)
|
|
socket.emit("ssherror", `SSH ${context}${errorMessage}`)
|
|
handleConnectionClose(socket)
|
|
}
|
|
|
|
/**
|
|
* Updates the specified element with the given value by emitting an "updateUI" event through the socket.
|
|
*
|
|
* @param {Socket} socket - The socket object used for communication.
|
|
* @param {string} element - The element to be updated.
|
|
* @param {string} value - The value to update the element with.
|
|
*/
|
|
function updateElement(socket, element, value) {
|
|
debug(`updateElement: ${socket.id}, Element: ${element}, Value: ${value}`)
|
|
socket.emit("updateUI", { element, value });
|
|
}
|
|
|
|
/**
|
|
* Validates the provided credentials and logs the result
|
|
* @param {Object} socket - The socket object containing the socket ID
|
|
* @param {Object} creds - The credentials to validate
|
|
* @returns {boolean} Whether the credentials are valid
|
|
*/
|
|
function isValidCredentials(socket, creds) {
|
|
// Basic format validation
|
|
const isValid =
|
|
creds &&
|
|
typeof creds.username === "string" &&
|
|
typeof creds.password === "string" &&
|
|
typeof creds.host === "string" &&
|
|
typeof creds.port === "number"
|
|
|
|
// Single line debug log with ternary operator
|
|
debug(
|
|
`isValidCredentials: CREDENTIALS ${isValid ? "VALID" : "INVALID"}: ${socket.id}${
|
|
isValid ? `, Host: ${creds.host}` : ""
|
|
}`
|
|
)
|
|
|
|
return isValid
|
|
}
|
|
|
|
/**
|
|
* Generates the SSH configuration object
|
|
* @param {Credentials} credentials - The user credentials
|
|
* @param {Object} config - The configuration object
|
|
* @returns {import('ssh2').ConnectConfig} The SSH configuration object
|
|
*/
|
|
function getSSHConfig(creds, config) {
|
|
debug(
|
|
`getSSHConfig: ${socket.id}, Host: ${JSON.stringify(sanitizeObject(creds))}`
|
|
)
|
|
|
|
const sshConfig = {
|
|
host: creds.host,
|
|
port: creds.port,
|
|
username: creds.username,
|
|
password: creds.password,
|
|
tryKeyboard: true,
|
|
algorithms: creds.algorithms || config.ssh.algorithms,
|
|
readyTimeout: creds.readyTimeout || config.ssh.readyTimeout,
|
|
keepaliveInterval:
|
|
creds.keepaliveInterval || config.ssh.keepaliveInterval,
|
|
keepaliveCountMax:
|
|
creds.keepaliveCountMax || config.ssh.keepaliveCountMax,
|
|
debug: createDebug("ssh")
|
|
}
|
|
debug(`getSSHConfig: ${JSON.stringify(sanitizeObject(sshConfig))}`)
|
|
return sshConfig
|
|
}
|
|
|
|
/**
|
|
* Clears the session credentials for a given socket.
|
|
*
|
|
* @param {Socket} socket - The socket object.
|
|
* @returns {void}
|
|
*/
|
|
function clearSessionCredentials(socket) {
|
|
debug(
|
|
`clearSessionCredentials: Clearing session credentials for ${socket.id}`
|
|
)
|
|
if (socket.handshake.session.sshCredentials) {
|
|
socket.handshake.session.sshCredentials.username = null
|
|
socket.handshake.session.sshCredentials.password = null
|
|
}
|
|
sessionState.authenticated = false
|
|
sessionState.username = null
|
|
sessionState.password = null
|
|
socket.handshake.session.save((err) => {
|
|
if (err) {
|
|
console.error(`Failed to save session for ${socket.id}:`, err)
|
|
}
|
|
})
|
|
}
|
|
}
|