## Summary
When network requests were blocked, downstream code often had to infer
ask vs deny from free-form response text. That was brittle and led to
incorrect approval behavior.
This PR fixes the proxy side so blocked decisions are structured and
request metadata survives reliably.
## Description
- Blocked proxy responses now carry consistent structured policy
decision data.
- Request attempt metadata is preserved across proxy env paths
(including ALL_PROXY flows).
- Header stripping was tightened so we still remove unsafe forwarding
headers, but keep metadata needed for policy handling.
- Block messages were clarified (for example, allowlist miss vs explicit
deny).
- Added unified violation log entries so policy failures can be
inspected in one place.
- Added/updated tests for these behaviors.
---------
Co-authored-by: Codex <199175422+chatgpt-codex-connector[bot]@users.noreply.github.com>
## Summary
- enable local-use defaults in network proxy settings: SOCKS5 on, SOCKS5
UDP on, upstream proxying on, and local binding on
- add a regression test that asserts the full
`NetworkProxySettings::default()` baseline
- Fixed managed listener reservation behavior.
Before: we always reserved a loopback SOCKS listener, even when
enable_socks5 = false.
Now: SOCKS listener is only reserved when SOCKS is enabled.
- Fixed /debug-config env output for SOCKS-disabled sessions.
ALL_PROXY now shows the HTTP proxy URL when SOCKS is disabled (instead
of incorrectly showing socks5h://...).
## Validation
- just fmt
- cargo test -p codex-network-proxy
- cargo clippy -p codex-network-proxy --all-targets
As of this PR, `SessionServices` retains a
`Option<StartedNetworkProxy>`, if appropriate.
Now the `network` field on `Config` is `Option<NetworkProxySpec>`
instead of `Option<NetworkProxy>`.
Over in `Session::new()`, we invoke `NetworkProxySpec::start_proxy()` to
create the `StartedNetworkProxy`, which is a new struct that retains the
`NetworkProxy` as well as the `NetworkProxyHandle`. (Note that `Drop` is
implemented for `NetworkProxyHandle` to ensure the proxies are shutdown
when it is dropped.)
The `NetworkProxy` from the `StartedNetworkProxy` is threaded through to
the appropriate places.
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/11207).
* #11285
* __->__ #11207
Codex may run many per-thread proxy instances, so hardcoded proxy ports
are brittle and conflict-prone. The previous "ephemeral" approach still
had a race: `build()` read `local_addr()` from temporary listeners and
dropped them before `run()` rebound the ports. That left a
[TOCTOU](https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use)
window where the OS (or another process) could reuse the same port,
causing intermittent `EADDRINUSE` and partial proxy startup.
Change the managed proxy path to reserve real listener sockets up front
and keep them alive until startup:
- add `ReservedListeners` on `NetworkProxy` to hold HTTP/SOCKS/admin std
listeners allocated during `build()`
- in managed mode, bind `127.0.0.1:0` for each listener and carry those
bound sockets into `run()` instead of rebinding by address later
- add `run_*_with_std_listener` entry points for HTTP, SOCKS5, and admin
servers so `run()` can start services from already-reserved sockets
- keep static/configured ports only when `managed_by_codex(false)`,
including explicit `socks_addr` override support
- remove fallback synthetic port allocation and add tests for managed
ephemeral loopback binding and unmanaged configured-port behavior
This makes managed startup deterministic, avoids port collisions, and
preserves the intended distinction between Codex-managed ephemeral ports
and externally managed fixed ports.
This PR adds the following field to `Config`:
```rust
pub network: Option<NetworkProxy>,
```
Though for the moment, it will always be initialized as `None` (this
will be addressed in a subsequent PR).
This PR does the work to thread `network` through to `execute_exec_env()`, `process_exec_tool_call()`, and `UnifiedExecRuntime.run()` to ensure it is available whenever we span a process.
Currently, `codex-network-proxy` depends on `codex-core`, but this
should be the other way around. As a first step, refactor out
`ConfigReloader`, which should make it easier to move
`codex-rs/network-proxy/src/state.rs` to `codex-core` in a subsequent
commit.
Summary:
- Rename config table from network_proxy to network.
- Flatten allowed_domains, denied_domains, allow_unix_sockets, and
allow_local_binding onto NetworkProxySettings.
- Update runtime, state constraints, tests, and README to the new config
shape.
## Summary
Add explicit, model-visible network policy decision metadata to blocked
proxy responses/errors.
Introduces a standardized prefix line: `CODEX_NETWORK_POLICY_DECISION
{json}`
and wires it through blocked paths for:
- HTTP requests
- HTTPS CONNECT
- SOCKS5 TCP/UDP denials
## Why
The model should see *why* a request was blocked
(reason/source/protocol/host/port) so it can choose the correct next
action.
## Notes
- This PR is intentionally independent of config-layering/network-rule
runtime integration.
- Focus is blocked decision surface only.
Load requirements from Codex Backend. It only does this for enterprise
customers signed in with ChatGPT.
Todo in follow-up PRs:
* Add to app-server and exec too
* Switch from fail-open to fail-closed on failure
Constructors with long param lists can be hard to reason about when a
number of the args are `None`, in practice. Introducing a struct to use
as the args type helps make things more self-documenting.
### Summary
- Adds an optional SOCKS5 listener via `rama-socks5`
- SOCKS5 is disabled by default and gated by config
- Reuses existing policy enforcement and blocked-request recording
- Blocks SOCKS5 in limited mode to prevent method-policy bypass
- Applies bind clamping to the SOCKS5 listener
### Config
New/used fields under `network_proxy`:
- `enable_socks5`
- `socks_url`
- `enable_socks5_udp`
### Scope
- Changes limited to `codex-rs/network-proxy` (+ `codex-rs/Cargo.lock`)
### Testing
```bash
cd codex-rs
just fmt
cargo test -p codex-network-proxy --offline
This add a new crate, `codex-network-proxy`, a local network proxy
service used by Codex to enforce fine-grained network policy (domain
allow/deny) and to surface blocked network events for interactive
approvals.
- New crate: `codex-rs/network-proxy/` (`codex-network-proxy` binary +
library)
- Core capabilities:
- HTTP proxy support (including CONNECT tunneling)
- SOCKS5 proxy support (in the later PR)
- policy evaluation (allowed/denied domain lists; denylist wins;
wildcard support)
- small admin API for polling/reload/mode changes
- optional MITM support for HTTPS CONNECT to enforce “limited mode”
method restrictions (later PR)
Will follow up integration with codex in subsequent PRs.
## Testing
- `cd codex-rs && cargo build -p codex-network-proxy`
- `cd codex-rs && cargo run -p codex-network-proxy -- proxy`
