fix: bound trans stdout and sanitize win ps json

2026-06-07 07:27:44 +00:00
parent 6144f159ce
commit 33ab2a79a5
5 changed files with 294 additions and 3 deletions
@@ -0,0 +1,76 @@
+import { describe, expect, test } from "bun:test";
+import {
+  createSshStdoutForwarder,
+  formatSshStdoutTruncationHint,
+  parseSshInvocation,
+  sshStdoutStreamMaxBytes,
+  sshStdoutTruncationHint,
+  windowsPowerShellScriptPrelude,
+} from "./ssh";
+
+describe("ssh windows PowerShell safety prelude", () => {
+  test("shadows ConvertTo-Json and strips filesystem ETS metadata", () => {
+    const prelude = windowsPowerShellScriptPrelude("C:\\test");
+
+    expect(prelude).toContain("function ConvertTo-UniDeskPlainJsonValue");
+    expect(prelude).toContain("function ConvertTo-Json");
+    expect(prelude).toContain("'PSPath','PSParentPath','PSChildName','PSDrive','PSProvider','ReadCount'");
+    expect(prelude).toContain("Microsoft.PowerShell.Utility\\ConvertTo-Json");
+    expect(prelude).toContain("Set-Location -LiteralPath 'C:\\test'");
+  });
+});
+
+describe("ssh stdout bounded streaming", () => {
+  test("uses bounded defaults and clamps env override", () => {
+    expect(sshStdoutStreamMaxBytes({} as NodeJS.ProcessEnv)).toBe(256 * 1024);
+    expect(sshStdoutStreamMaxBytes({ UNIDESK_SSH_STDOUT_STREAM_MAX_BYTES: "8192" } as NodeJS.ProcessEnv)).toBe(8192);
+    expect(sshStdoutStreamMaxBytes({ UNIDESK_SSH_STDOUT_STREAM_MAX_BYTES: "1" } as NodeJS.ProcessEnv)).toBe(4096);
+    expect(sshStdoutStreamMaxBytes({ UNIDESK_SSH_STDOUT_STREAM_MAX_BYTES: String(64 * 1024 * 1024) } as NodeJS.ProcessEnv)).toBe(16 * 1024 * 1024);
+  });
+
+  test("formats truncation hint without echoing remote command", () => {
+    const invocation = parseSshInvocation("D601:win", ["ps"]);
+    expect(invocation.parsed.remoteCommand).not.toBeNull();
+    const hint = sshStdoutTruncationHint({
+      invocation,
+      transport: "backend-core-broker",
+      thresholdBytes: 4096,
+      observedBytesAtTruncation: 5000,
+      dumpPath: "/tmp/unidesk-cli-output/sample.stdout.bin",
+    });
+    const formatted = formatSshStdoutTruncationHint(hint);
+
+    expect(formatted.startsWith("UNIDESK_SSH_STDOUT_TRUNCATED ")).toBe(true);
+    const payload = JSON.parse(formatted.slice("UNIDESK_SSH_STDOUT_TRUNCATED ".length)) as Record<string, unknown>;
+    expect(payload.code).toBe("ssh-stdout-truncated");
+    expect(payload.providerId).toBe("D601");
+    expect(payload.route).toBe("D601:win");
+    expect(payload.thresholdBytes).toBe(4096);
+    expect(formatted).not.toContain("Get-Content");
+  });
+
+  test("forwarder bounds stdout and emits one truncation hint", () => {
+    const invocation = parseSshInvocation("D601:win", ["ps"]);
+    const forwarded: Buffer[] = [];
+    const stdout = {
+      write(chunk: string | Buffer): boolean {
+        forwarded.push(Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk));
+        return true;
+      },
+    } as NodeJS.WritableStream;
+    const forwarder = createSshStdoutForwarder({
+      invocation,
+      transport: "frontend-websocket",
+      maxBytes: 5,
+      stdout,
+    });
+
+    expect(forwarder.write(Buffer.from("abc"))).toBeNull();
+    const hint = forwarder.write(Buffer.from("defgh"));
+    expect(hint).not.toBeNull();
+    expect(forwarder.write(Buffer.from("ijkl"))).toBeNull();
+    expect(Buffer.concat(forwarded).toString("utf8")).toBe("abcde");
+    expect(hint).toContain("UNIDESK_SSH_STDOUT_TRUNCATED");
+    expect(hint).toContain("\"transport\":\"frontend-websocket\"");
+  });
+});