From b7d034d75bce68531c6d072d7dcdad47e89b32a5 Mon Sep 17 00:00:00 2001
From: mushuiyu886 <yang.haoyu@xydigit.com>
Date: Tue, 14 Jul 2026 00:29:41 +0800
Subject: [PATCH] fix(cli): reject noncanonical trajectory export requests
 (#105557)

* fix(cli): reject noncanonical trajectory export requests

* fix(cli): preserve encoded request bytes

* style(cli): format trajectory alias tests

* chore: keep trajectory note in PR context

---------

Co-authored-by: Peter Steinberger <peter@steipete.me>
Co-authored-by: Peter Steinberger <steipete@gmail.com>
---
 src/commands/export-trajectory.test.ts | 21 +++++++++++++++++++++
 src/commands/export-trajectory.ts      | 13 ++++++++-----
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/src/commands/export-trajectory.test.ts b/src/commands/export-trajectory.test.ts
index b7e845182594..585f20ff06d1 100644
--- a/src/commands/export-trajectory.test.ts
+++ b/src/commands/export-trajectory.test.ts
@@ -85,6 +85,27 @@ describe("exportTrajectoryCommand", () => {
     expect(runtime.exit).toHaveBeenCalledWith(1);
   });
 
+  it.each([
+    ["a discarded suffix", (encoded: string) => `${encoded}A`, "x"],
+    ["nonzero padding bits", (encoded: string) => `${encoded.slice(0, -1)}R`, "xy"],
+    ["surrounding whitespace", (encoded: string) => ` ${encoded} `, "xyz"],
+  ])(
+    "rejects a non-canonical base64url request with %s before looking up its session",
+    async (_case, makeNonCanonical, sessionKey) => {
+      const runtime = createRuntime();
+      const canonical = Buffer.from(JSON.stringify({ sessionKey }), "utf8").toString("base64url");
+      const requestJsonBase64 = makeNonCanonical(canonical);
+
+      await exportTrajectoryCommand({ requestJsonBase64 }, runtime);
+
+      expect(runtime.error).toHaveBeenCalledWith(
+        "Failed to decode trajectory export request: Encoded trajectory export request is invalid",
+      );
+      expect(mocks.loadSessionEntry).not.toHaveBeenCalled();
+      expect(runtime.exit).toHaveBeenCalledWith(1);
+    },
+  );
+
   it("preserves direct options when an encoded request omits them", async () => {
     const runtime = createRuntime();
     const requestJsonBase64 = Buffer.from(
diff --git a/src/commands/export-trajectory.ts b/src/commands/export-trajectory.ts
index b22e2a5b2cba..5a48f0a71e5c 100644
--- a/src/commands/export-trajectory.ts
+++ b/src/commands/export-trajectory.ts
@@ -43,13 +43,16 @@ function readOptionalString(value: unknown): string | undefined {
 }
 
 function decodeExportTrajectoryRequest(encoded: string): Partial<ExportTrajectoryCommandOptions> {
-  const trimmed = encoded.trim();
-  if (!ENCODED_EXPORT_REQUEST_RE.test(trimmed)) {
+  if (!ENCODED_EXPORT_REQUEST_RE.test(encoded)) {
+    throw new Error("Encoded trajectory export request is invalid");
+  }
+  const bytes = Buffer.from(encoded, "base64url");
+  if (bytes.toString("base64url") !== encoded) {
     throw new Error("Encoded trajectory export request is invalid");
   }
   let decoded: unknown;
   try {
-    decoded = JSON.parse(Buffer.from(trimmed, "base64url").toString("utf8")) as unknown;
+    decoded = JSON.parse(bytes.toString("utf8")) as unknown;
   } catch {
     throw new Error("Encoded trajectory export request is invalid JSON");
   }
@@ -84,8 +87,8 @@ function decodeExportTrajectoryRequest(encoded: string): Partial<ExportTrajector
 function resolveExportTrajectoryOptions(
   opts: ExportTrajectoryCommandOptions,
 ): ExportTrajectoryCommandOptions {
-  const encoded = opts.requestJsonBase64?.trim();
-  if (!encoded) {
+  const encoded = opts.requestJsonBase64;
+  if (encoded === undefined || encoded.length === 0) {
     return opts;
   }
   return {