[ACR] Harden downloadBlob and getManifest validation (#25769)

### Packages impacted by this PR

- `@azure/container-registry`

### Issues associated with this PR

- Fix #25645

### Describe the problem that is addressed by this PR

Add extra validation to `downloadBlob` and `getManifest`:
- Restrict manifest size to 4 MB
- Throw early if bytes read during `downloadBlob` exceed the value in
the
  `Content-Length` header

Based somewhat on the [Java PR for the same
thing](Azure/azure-sdk-for-java#34737), but
without validation of the `Content-Range` header since we are using
optimistic download.

sdk/containerregistry/container-registry/src/content/containerRegistryContentClient.ts

@@ -36,6 +36,7 @@ import { RetriableReadableStream } from "../utils/retriableReadableStream";
 const LATEST_API_VERSION = "2021-07-01";
 
 const CHUNK_SIZE = 4 * 1024 * 1024; // 4 MB
+const MAX_MANIFEST_SIZE_BYTES = 4 * 1024 * 1024; // 4 MB
 
 const ACCEPTED_MANIFEST_MEDIA_TYPES = [
   KnownManifestMediaType.OciImageManifest,
@@ -254,7 +255,7 @@ export class ContainerRegistryContentClient {
         assertHasProperty(response, "mediaType");
 
         const content = response.readableStreamBody
-          ? await readStreamToEnd(response.readableStreamBody)
+          ? await readStreamToEnd(response.readableStreamBody, MAX_MANIFEST_SIZE_BYTES)
           : Buffer.alloc(0);
 
         const expectedDigest = await calculateDigest(content);

sdk/containerregistry/container-registry/src/utils/helpers.ts

@@ -20,11 +20,22 @@ export function isDigest(tagOrDigest: string): boolean {
   return tagOrDigest.includes(":");
 }
 
-export async function readStreamToEnd(stream: NodeJS.ReadableStream): Promise<Buffer> {
+export async function readStreamToEnd(
+  stream: NodeJS.ReadableStream,
+  maxLength?: number
+): Promise<Buffer> {
   const buffers: Buffer[] = [];
+  let bytesRead = 0;
 
   return new Promise((resolve, reject) => {
-    stream.on("data", (chunk) => buffers.push(chunk));
+    stream.on("data", (chunk) => {
+      buffers.push(chunk);
+      bytesRead += chunk.length;
+
+      if (maxLength && bytesRead > maxLength) {
+        reject(new Error(`Stream exceeded maximum allowed length of ${maxLength} bytes.`));
+      }
+    });
     stream.on("end", () => resolve(Buffer.concat(buffers)));
     stream.on("error", (err) => reject(err));
   });

sdk/containerregistry/container-registry/src/utils/retriableReadableStream.ts

@@ -121,6 +121,16 @@ export class RetriableReadableStream extends Readable {
 
     this.offset += data.length;
 
+    if (this.offset > this.end + 1) {
+      this.destroy(
+        new Error(
+          `Data corruption failure: Received more data than original request, data needed offset is ${
+            this.end
+          }, received offset: ${this.offset - 1}`
+        )
+      );
+    }
+
     this.onData?.(data);
     this.onProgress?.({ loadedBytes: this.offset - this.start });