SSH session multiplexing - fixes #4795

tabby-ssh/src/api/interfaces.ts

@@ -32,6 +32,7 @@ export interface SSHProfileOptions extends LoginScriptsOptions {
     forwardedPorts?: ForwardedPortConfig[]
     socksProxyHost?: string
     socksProxyPort?: number
+    reuseSession?: boolean
 }
 
 export enum PortForwardType {

tabby-ssh/src/components/sshProfileSettings.component.pug

@@ -162,6 +162,12 @@ ul.nav-tabs(ngbNav, #nav='ngbNav')
                     .description Will prevent the SSH greeting from showing up
                 toggle([(ngModel)]='profile.options.skipBanner')
 
+            .form-line
+                .header
+                    .title Reuse session for multiple tabs
+                    .description Multiplex multiple shells through the same connection
+                toggle([(ngModel)]='profile.options.reuseSession')
+
             .form-line
                 .header
                     .title Keep Alive Interval (Milliseconds)

tabby-ssh/src/components/sshTab.component.ts

@@ -9,6 +9,7 @@ import { KeyboardInteractivePrompt, SSHSession } from '../session/ssh'
 import { SSHPortForwardingModalComponent } from './sshPortForwardingModal.component'
 import { SSHProfile } from '../api'
 import { SSHShellSession } from '../session/shell'
+import { SSHMultiplexerService } from '../services/sshMultiplexer.service'
 
 /** @hidden */
 @Component({
@@ -26,7 +27,6 @@ export class SSHTabComponent extends BaseTerminalTabComponent {
     sftpPath = '/'
     enableToolbar = true
     activeKIPrompt: KeyboardInteractivePrompt|null = null
-    private sessionStack: SSHSession[] = []
     private recentInputs = ''
     private reconnectOffered = false
 
@@ -35,6 +35,7 @@ export class SSHTabComponent extends BaseTerminalTabComponent {
         public ssh: SSHService,
         private ngbModal: NgbModal,
         private profilesService: ProfilesService,
+        private sshMultiplexer: SSHMultiplexerService,
     ) {
         super(injector)
         this.sessionChanged$.subscribe(() => {
@@ -82,50 +83,45 @@ export class SSHTabComponent extends BaseTerminalTabComponent {
         super.ngOnInit()
     }
 
-    async setupOneSession (session: SSHSession, interactive: boolean): Promise<void> {
-        if (session.profile.options.jumpHost) {
-            const jumpConnection: PartialProfile<SSHProfile>|null = this.config.store.profiles.find(x => x.id === session.profile.options.jumpHost)
+    async setupOneSession (injector: Injector, profile: SSHProfile): Promise<SSHSession> {
+        let session = this.sshMultiplexer.getSession(profile)
+        if (!session || !profile.options.reuseSession) {
+            session = new SSHSession(injector, profile)
 
-            if (!jumpConnection) {
-                throw new Error(`${session.profile.options.host}: jump host "${session.profile.options.jumpHost}" not found in your config`)
-            }
+            if (profile.options.jumpHost) {
+                const jumpConnection: PartialProfile<SSHProfile>|null = this.config.store.profiles.find(x => x.id === profile.options.jumpHost)
 
-            const jumpSession = new SSHSession(
-                this.injector,
-                this.profilesService.getConfigProxyForProfile(jumpConnection)
-            )
-
-            await this.setupOneSession(jumpSession, false)
-
-            this.attachSessionHandler(jumpSession.willDestroy$, () => {
-                if (session.open) {
-                    session.destroy()
+                if (!jumpConnection) {
+                    throw new Error(`${profile.options.host}: jump host "${profile.options.jumpHost}" not found in your config`)
                 }
-            })
 
-            session.jumpStream = await new Promise((resolve, reject) => jumpSession.ssh.forwardOut(
-                '127.0.0.1', 0, session.profile.options.host, session.profile.options.port ?? 22,
-                (err, stream) => {
-                    if (err) {
-                        jumpSession.emitServiceMessage(colors.bgRed.black(' X ') + ` Could not set up port forward on ${jumpConnection.name}`)
-                        reject(err)
-                        return
+                const jumpSession = await this.setupOneSession(
+                    this.injector,
+                    this.profilesService.getConfigProxyForProfile(jumpConnection)
+                )
+
+                jumpSession.ref()
+                session.willDestroy$.subscribe(() => jumpSession.unref())
+                jumpSession.willDestroy$.subscribe(() => {
+                    if (session?.open) {
+                        session.destroy()
                     }
-                    resolve(stream)
-                }
-            ))
+                })
 
-            session.jumpStream.on('close', () => {
-                jumpSession.destroy()
-            })
-
-            this.sessionStack.push(session)
+                session.jumpStream = await new Promise((resolve, reject) => jumpSession.ssh.forwardOut(
+                    '127.0.0.1', 0, profile.options.host, profile.options.port ?? 22,
+                    (err, stream) => {
+                        if (err) {
+                            jumpSession.emitServiceMessage(colors.bgRed.black(' X ') + ` Could not set up port forward on ${jumpConnection.name}`)
+                            reject(err)
+                            return
+                        }
+                        resolve(stream)
+                    }
+                ))
+            }
         }
 
-        this.write('\r\n' + colors.black.bgWhite(' SSH ') + ` Connecting to ${session.profile.options.host}\r\n`)
-
-        this.startSpinner('Connecting')
-
         this.attachSessionHandler(session.serviceMessage$, msg => {
             this.write(`\r${colors.black.bgWhite(' SSH ')} ${msg}\r\n`)
         })
@@ -141,14 +137,24 @@ export class SSHTabComponent extends BaseTerminalTabComponent {
             })
         })
 
-        try {
-            await session.start(interactive)
-            this.stopSpinner()
-        } catch (e) {
-            this.stopSpinner()
-            this.write(colors.black.bgRed(' X ') + ' ' + colors.red(e.message) + '\r\n')
-            return
+        if (!session.open) {
+            this.write('\r\n' + colors.black.bgWhite(' SSH ') + ` Connecting to ${session.profile.options.host}\r\n`)
+
+            this.startSpinner('Connecting')
+
+            try {
+                await session.start()
+                this.stopSpinner()
+            } catch (e) {
+                this.stopSpinner()
+                this.write(colors.black.bgRed(' X ') + ' ' + colors.red(e.message) + '\r\n')
+                return session
+            }
+
+            this.sshMultiplexer.addSession(session)
         }
+
+        return session
     }
 
     protected attachSessionHandlers (): void {
@@ -185,11 +191,11 @@ export class SSHTabComponent extends BaseTerminalTabComponent {
             return
         }
 
-        this.sshSession = new SSHSession(this.injector, this.profile)
         try {
-            await this.setupOneSession(this.sshSession, true)
+            this.sshSession = await this.setupOneSession(this.injector, this.profile)
         } catch (e) {
             this.write(colors.black.bgRed(' X ') + ' ' + colors.red(e.message) + '\r\n')
+            return
         }
 
         const session = new SSHShellSession(this.injector, this.sshSession)

tabby-ssh/src/profiles.ts

@@ -39,6 +39,7 @@ export class SSHProfilesService extends ProfileProvider<SSHProfile> {
             scripts: [],
             socksProxyHost: null,
             socksProxyPort: null,
+            reuseSession: true,
         },
     }
 

tabby-ssh/src/services/sshMultiplexer.service.ts

@@ -0,0 +1,38 @@
+import { Injectable } from '@angular/core'
+import { SSHProfile } from '../api'
+import { ConfigService, PartialProfile, ProfilesService } from 'tabby-core'
+import { SSHSession } from '../session/ssh'
+
+@Injectable({ providedIn: 'root' })
+export class SSHMultiplexerService {
+    private sessions = new Map<string, SSHSession>()
+
+    constructor (
+        private config: ConfigService,
+        private profilesService: ProfilesService,
+    ) { }
+
+    addSession (session: SSHSession): void {
+        const key = this.getMultiplexerKey(session.profile)
+        this.sessions.set(key, session)
+        session.willDestroy$.subscribe(() => {
+            this.sessions.delete(key)
+        })
+    }
+
+    getSession (profile: PartialProfile<SSHProfile>): SSHSession|null {
+        const fullProfile = this.profilesService.getConfigProxyForProfile(profile)
+        const key = this.getMultiplexerKey(fullProfile)
+        return this.sessions.get(key) ?? null
+    }
+
+    private getMultiplexerKey (profile: SSHProfile) {
+        let key = `${profile.options.host}:${profile.options.port}:${profile.options.user}:${profile.options.proxyCommand}:${profile.options.socksProxyHost}:${profile.options.socksProxyPort}`
+        if (profile.options.jumpHost) {
+            const jumpConnection = this.config.store.profiles.find(x => x.id === profile.options.jumpHost)
+            const jumpProfile = this.profilesService.getConfigProxyForProfile(jumpConnection)
+            key += '$' + this.getMultiplexerKey(jumpProfile)
+        }
+        return key
+    }
+}

tabby-ssh/src/session/shell.ts

@@ -77,6 +77,7 @@ export class SSHShellSession extends BaseSession {
         this.serviceMessage.next(msg)
         this.logger.info(stripAnsi(msg))
     }
+
     resize (columns: number, rows: number): void {
         if (this.shell) {
             this.shell.setWindow(rows, columns, rows, columns)

tabby-ssh/src/session/ssh.ts

@@ -169,7 +169,7 @@ export class SSHSession {
     }
 
 
-    async start (interactive = true): Promise<void> {
+    async start (): Promise<void> {
         const log = (s: any) => this.emitServiceMessage(s)
 
         const ssh = new Client()
@@ -306,10 +306,6 @@ export class SSHSession {
 
         this.open = true
 
-        if (!interactive) {
-            return
-        }
-
         this.ssh.on('tcp connection', (details, accept, reject) => {
             this.logger.info(`Incoming forwarded connection: (remote) ${details.srcIP}:${details.srcPort} -> (local) ${details.destIP}:${details.destPort}`)
             const forward = this.forwardedPorts.find(x => x.port === details.destPort)