fix: split provider ssh tty modes

src/components/backend-core/src/index.ts

@@ -1097,7 +1097,7 @@ function numberFromUnknown(value: unknown, fallback: number, min: number, max: n
 
 async function handleSshClientMessage(ws: ProviderSocket, raw: string | Buffer): Promise<void> {
   const text = typeof raw === "string" ? raw : raw.toString("utf8");
-  const message = JSON.parse(text) as { type?: unknown; providerId?: unknown; cwd?: unknown; command?: unknown; data?: unknown; encoding?: unknown; cols?: unknown; rows?: unknown };
+  const message = JSON.parse(text) as { type?: unknown; providerId?: unknown; cwd?: unknown; command?: unknown; tty?: unknown; data?: unknown; encoding?: unknown; cols?: unknown; rows?: unknown };
   if (message.type === "ssh.open") {
     const providerId = typeof message.providerId === "string" ? message.providerId : "";
     if (providerId.length === 0) {
@@ -1126,6 +1126,7 @@ async function handleSshClientMessage(ws: ProviderSocket, raw: string | Buffer):
     };
     if (typeof message.cwd === "string" && message.cwd.length > 0) openMessage.cwd = message.cwd;
     if (typeof message.command === "string" && message.command.length > 0) openMessage.command = message.command;
+    if (typeof message.tty === "boolean") openMessage.tty = message.tty;
     provider.send(JSON.stringify(openMessage));
     wsSendJson(ws, { type: "ssh.dispatched", providerId, sessionId });
     logger("info", "ssh_session_dispatched", { providerId, sessionId, hasCommand: typeof openMessage.command === "string" });

src/components/provider-gateway/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@unidesk/provider-gateway",
-  "version": "0.2.7",
+  "version": "0.2.8",
   "private": true,
   "type": "module",
   "scripts": {

src/components/provider-gateway/scripts/host-ssh-shell.sh

@@ -17,8 +17,12 @@ q_requested=$(quote "$requested_cwd")
 q_fallback=$(quote "$fallback_cwd")
 q_shell=$(quote "$login_shell")
 remote_cmd="cd $q_requested 2>/dev/null || cd $q_fallback 2>/dev/null || cd; export UNIDESK_BRIDGE=host-ssh; exec $q_shell -l"
+tty_arg="-T"
+if [ -t 0 ] && [ -t 1 ]; then
+  tty_arg="-tt"
+fi
 
-exec ssh -tt \
+exec ssh "$tty_arg" \
   -i "$key" \
   -p "$port" \
   -o BatchMode=yes \

src/components/provider-gateway/src/index.ts

@@ -69,6 +69,7 @@ let upgradeSleepTimer: ReturnType<typeof setTimeout> | null = null;
 interface HostSshSession {
   proc: ReturnType<typeof Bun.spawn>;
   openedAt: number;
+  tty: boolean;
 }
 
 interface HostSshStdin {
@@ -963,12 +964,12 @@ async function runHostSsh(payload: Record<string, JsonValue>): Promise<JsonValue
   };
 }
 
-function hostSshRemoteScript(command: string | null, cwd: string | null, cols?: number, rows?: number): string {
+function hostSshRemoteScript(command: string | null, cwd: string | null, allocateTty: boolean, cols?: number, rows?: number): string {
   const fallbackCwd = config.hostRemoteCwd ?? `/home/${config.hostSshUser ?? "root"}`;
   const requestedCwd = cwd ?? fallbackCwd;
   if (command !== null && command.length > 0) assertHostSshCommandAllowed(command, requestedCwd);
   const loginShell = config.hostLoginShell ?? "/bin/bash";
-  const resize = Number.isFinite(cols) && Number.isFinite(rows)
+  const resize = allocateTty && Number.isFinite(cols) && Number.isFinite(rows)
     ? `stty rows ${Math.max(8, Math.min(120, Math.floor(rows ?? 30)))} cols ${Math.max(20, Math.min(300, Math.floor(cols ?? 100)))} 2>/dev/null || true`
     : "true";
   const enterCwd = `cd ${shellQuote(requestedCwd)} 2>/dev/null || cd ${shellQuote(fallbackCwd)} 2>/dev/null || cd`;
@@ -979,7 +980,7 @@ function hostSshRemoteScript(command: string | null, cwd: string | null, cols?:
   return `${enterCwd}; ${exports}; ${resize}; ${execPart}`;
 }
 
-function hostSshArgs(remoteScript: string): string[] {
+function hostSshArgs(remoteScript: string, allocateTty: boolean): string[] {
   if (!isHostSshConfigured()) {
     throw new Error(`host SSH bridge is not configured; missing ${missingHostSshFields().join(", ")}`);
   }
@@ -988,7 +989,7 @@ function hostSshArgs(remoteScript: string): string[] {
     throw new Error(`host SSH key is not mounted at ${key}`);
   }
   return [
-    "-tt",
+    allocateTty ? "-tt" : "-T",
     "-i",
     key,
     "-p",
@@ -1044,13 +1045,15 @@ function startHostSshSession(message: CoreHostSshOpenMessage): void {
     return;
   }
   try {
-    const remoteScript = hostSshRemoteScript(message.command ?? null, message.cwd ?? null, message.cols, message.rows);
-    const proc = Bun.spawn(["ssh", ...hostSshArgs(remoteScript)], {
+    const command = typeof message.command === "string" && message.command.length > 0 ? message.command : null;
+    const allocateTty = typeof message.tty === "boolean" ? message.tty : command === null;
+    const remoteScript = hostSshRemoteScript(command, message.cwd ?? null, allocateTty, message.cols, message.rows);
+    const proc = Bun.spawn(["ssh", ...hostSshArgs(remoteScript, allocateTty)], {
       stdin: "pipe",
       stdout: "pipe",
       stderr: "pipe",
     });
-    hostSshSessions.set(message.sessionId, { proc, openedAt: Date.now() });
+    hostSshSessions.set(message.sessionId, { proc, openedAt: Date.now(), tty: allocateTty });
     sendJson({
       type: "host_ssh_opened",
       providerId: config.providerId,
@@ -1075,7 +1078,7 @@ function startHostSshSession(message: CoreHostSshOpenMessage): void {
         hostSshSessions.delete(message.sessionId);
         sendHostSshError(message.sessionId, error);
       });
-    logger("info", "host_ssh_session_started", { sessionId: message.sessionId, hasCommand: typeof message.command === "string", cwd: message.cwd ?? null });
+    logger("info", "host_ssh_session_started", { sessionId: message.sessionId, hasCommand: command !== null, tty: allocateTty, cwd: message.cwd ?? null });
   } catch (error) {
     sendHostSshError(message.sessionId, error);
   }
@@ -1090,7 +1093,9 @@ function writeHostSshInput(message: CoreHostSshInputMessage): void {
   try {
     const stdin = session.proc.stdin as HostSshStdin | undefined;
     if (stdin === undefined) throw new Error("host SSH stdin is not available");
-    stdin.write(Buffer.from(message.data, "base64"));
+    const chunk = Buffer.from(message.data, "base64");
+    if (!session.tty && chunk.length === 1 && chunk[0] === 4) return;
+    stdin.write(chunk);
   } catch (error) {
     sendHostSshError(message.sessionId, error);
   }

src/components/shared/src/index.ts

@@ -143,6 +143,7 @@ export interface CoreHostSshOpenMessage {
   sessionId: string;
   cwd?: string;
   command?: string;
+  tty?: boolean;
   cols?: number;
   rows?: number;
 }