Shared from "Claude-Code" on Inkdown
How Claude Code Remote (CCR) containers handle outbound network traffic securely.
When Claude Code runs inside a CCR (Claude Code Remote) container, all outbound network traffic must be proxied through the CCR server for security and monitoring. The upstreamproxy system handles this.
upstreamproxy.ts)| Measure | Purpose |
|---|---|
prctl(PR_SET_DUMPABLE, 0) | Prevents ptrace-based attacks |
| One-time token | Session token deleted after use |
| Localhost-only | Proxy only listens on 127.0.0.1 |
| Custom CA | MITM proxy uses CCR-signed certs |
relay.ts)A CONNECT-over-WebSocket relay that tunnels HTTP/HTTPS traffic:
Uses hand-encoded protobuf (UpstreamProxyChunk):
Works with both Bun and Node:
After proxy initialization, these env vars are set:
This ensures all tools (curl, gh, kubectl, npm, pip, etc.) route through the proxy.
| File | Purpose |
|---|---|
src/upstreamproxy/upstreamproxy.ts | MITM proxy initialization |
src/upstreamproxy/relay.ts | WebSocket relay |