Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
157 changes: 157 additions & 0 deletions codex-rs/network-proxy/src/connect_policy.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,157 @@
use crate::policy::is_non_public_ip;
use crate::state::NetworkProxyState;
use rama_core::Service;
use rama_core::error::BoxError;
use rama_core::error::ErrorExt as _;
use rama_core::error::OpaqueError;
use rama_core::extensions::ExtensionsMut;
use rama_net::address::ProxyAddress;
use rama_net::client::EstablishedClientConnection;
use rama_net::transport::TryRefIntoTransportContext;
use rama_tcp::TcpStream;
use rama_tcp::client::TcpStreamConnector;
use rama_tcp::client::service::TcpConnector;
use std::io;
use std::net::SocketAddr;
use std::sync::Arc;

#[derive(Clone)]
pub(crate) struct TargetCheckedTcpConnector {
policy: TargetPolicy,
}

impl TargetCheckedTcpConnector {
pub(crate) fn new(state: Arc<NetworkProxyState>) -> Self {
Self {
policy: TargetPolicy::State(state),
}
}

pub(crate) fn from_allow_local_binding(allow_local_binding: bool) -> Self {
Self {
policy: TargetPolicy::Config {
allow_local_binding,
},
}
}
}

impl<Input> Service<Input> for TargetCheckedTcpConnector
where
Input: TryRefIntoTransportContext + Send + ExtensionsMut + 'static,
Input::Error: Into<BoxError> + Send + Sync + 'static,
{
type Output = EstablishedClientConnection<TcpStream, Input>;
type Error = BoxError;

async fn serve(&self, input: Input) -> Result<Self::Output, Self::Error> {
if input.extensions().get::<ProxyAddress>().is_some() {
return TcpConnector::new().serve(input).await;
}

TcpConnector::new()
.with_connector(TargetCheckedStreamConnector {
policy: self.policy.clone(),
})
.serve(input)
.await
}
}

#[derive(Clone)]
struct TargetCheckedStreamConnector {
policy: TargetPolicy,
}

impl TcpStreamConnector for TargetCheckedStreamConnector {
type Error = BoxError;

async fn connect(&self, addr: SocketAddr) -> Result<TcpStream, Self::Error> {
if !self.policy.allow_local_binding().await? && is_non_public_ip(addr.ip()) {
Copy link
Copy Markdown
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

P1 Badge Preserve explicit local allowlist in target recheck

Rejecting all non-public socket addresses when allow_local_binding is false regresses a supported policy path: NetworkProxyState::host_blocked intentionally permits explicitly allowlisted local literals. With this connector check, allowlisted targets like localhost/10.0.0.1 pass host policy but are still denied at connect time (PermissionDenied), so valid configurations now fail.

Useful? React with 👍 / 👎.

return Err(io::Error::new(
io::ErrorKind::PermissionDenied,
"network target rejected by policy",
)
.into());
}

tokio::net::TcpStream::connect(addr)
.await
.map(TcpStream::from)
.map_err(Into::into)
}
}

#[derive(Clone)]
enum TargetPolicy {
Config { allow_local_binding: bool },
State(Arc<NetworkProxyState>),
}

impl TargetPolicy {
async fn allow_local_binding(&self) -> Result<bool, BoxError> {
match self {
Self::Config {
allow_local_binding,
} => Ok(*allow_local_binding),
Self::State(state) => state.allow_local_binding().await.map_err(|err| {
let err: BoxError = err.into();
OpaqueError::from_boxed(err)
.context("read network proxy config")
.into_boxed()
}),
}
}
}

#[cfg(test)]
mod tests {
use super::*;
use crate::config::NetworkProxySettings;
use crate::state::network_proxy_state_for_policy;
use rama_net::address::HostWithPort;
use std::net::Ipv4Addr;
use tokio::net::TcpListener;

#[tokio::test(flavor = "current_thread")]
async fn direct_connector_rejects_non_public_target_when_local_binding_disabled() {
let listener = TcpListener::bind((Ipv4Addr::LOCALHOST, 0))
.await
.expect("bind local listener");
let target = listener.local_addr().expect("local addr");
let connector = TargetCheckedTcpConnector::new(Arc::new(network_proxy_state_for_policy(
NetworkProxySettings::default(),
)));

let request: rama_tcp::client::Request =
rama_tcp::client::Request::new(HostWithPort::from(target));
let err = Service::serve(&connector, request)
.await
.expect_err("local target should be rejected");

assert!(
format!("{err:?}").contains("network target rejected by policy"),
"unexpected error: {err:?}"
);
}

#[tokio::test(flavor = "current_thread")]
async fn direct_connector_allows_non_public_target_when_local_binding_enabled() {
let listener = TcpListener::bind((Ipv4Addr::LOCALHOST, 0))
.await
.expect("bind local listener");
let target = listener.local_addr().expect("local addr");
let connector = TargetCheckedTcpConnector::new(Arc::new(network_proxy_state_for_policy(
NetworkProxySettings {
allow_local_binding: true,
..NetworkProxySettings::default()
},
)));

let request: rama_tcp::client::Request =
rama_tcp::client::Request::new(HostWithPort::from(target));
let result = Service::serve(&connector, request).await;

assert!(result.is_ok(), "local target should be allowed: {result:?}");
}
}
29 changes: 16 additions & 13 deletions codex-rs/network-proxy/src/http_proxy.rs
Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
use crate::config::NetworkMode;
use crate::connect_policy::TargetCheckedTcpConnector;
use crate::mitm;
use crate::network_policy::BlockDecisionAuditEventArgs;
use crate::network_policy::NetworkDecision;
Expand Down Expand Up @@ -66,7 +67,6 @@ use rama_net::proxy::ProxyTarget;
use rama_net::proxy::StreamForwardService;
use rama_net::stream::SocketInfo;
use rama_tcp::client::Request as TcpRequest;
use rama_tcp::client::service::TcpConnector;
use rama_tcp::server::TcpListener;
use rama_tls_rustls::client::TlsConnectorDataBuilder;
use rama_tls_rustls::client::TlsConnectorLayer;
Expand Down Expand Up @@ -345,20 +345,22 @@ async fn http_connect_proxy(upgraded: Upgraded) -> Result<(), Infallible> {
return Ok(());
}

let allow_upstream_proxy = match upgraded
let app_state = match upgraded
.extensions()
.get::<Arc<NetworkProxyState>>()
.cloned()
{
Some(state) => match state.allow_upstream_proxy().await {
Ok(allowed) => allowed,
Err(err) => {
error!("failed to read upstream proxy setting: {err}");
false
}
},
Some(state) => state,
None => {
error!("missing app state");
return Ok(());
}
};

let allow_upstream_proxy = match app_state.allow_upstream_proxy().await {
Ok(allowed) => allowed,
Err(err) => {
error!("failed to read upstream proxy setting: {err}");
false
}
};
Expand All @@ -369,7 +371,7 @@ async fn http_connect_proxy(upgraded: Upgraded) -> Result<(), Infallible> {
None
};

if let Err(err) = forward_connect_tunnel(upgraded, proxy).await {
if let Err(err) = forward_connect_tunnel(upgraded, proxy, app_state).await {
warn!("tunnel error: {err}");
}
Ok(())
Expand All @@ -378,6 +380,7 @@ async fn http_connect_proxy(upgraded: Upgraded) -> Result<(), Infallible> {
async fn forward_connect_tunnel(
upgraded: Upgraded,
proxy: Option<ProxyAddress>,
app_state: Arc<NetworkProxyState>,
) -> Result<(), BoxError> {
let authority = upgraded
.extensions()
Expand All @@ -392,7 +395,7 @@ async fn forward_connect_tunnel(

let req = TcpRequest::new_with_extensions(authority.clone(), extensions)
.with_protocol(Protocol::HTTPS);
let proxy_connector = HttpProxyConnector::optional(TcpConnector::new());
let proxy_connector = HttpProxyConnector::optional(TargetCheckedTcpConnector::new(app_state));
let tls_config = TlsConnectorDataBuilder::new()
.with_alpn_protocols_http_auto()
.build();
Expand Down Expand Up @@ -730,9 +733,9 @@ async fn http_plain_proxy(
Err(resp) => return Ok(resp),
};
let client = if allow_upstream_proxy {
UpstreamClient::from_env_proxy()
UpstreamClient::from_env_proxy(app_state.clone())
} else {
UpstreamClient::direct()
UpstreamClient::direct(app_state.clone())
};

// Strip hop-by-hop headers only after extracting metadata used for policy correlation.
Expand Down
1 change: 1 addition & 0 deletions codex-rs/network-proxy/src/lib.rs
Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,7 @@

mod certs;
mod config;
mod connect_policy;
mod http_proxy;
mod mitm;
mod network_policy;
Expand Down
13 changes: 9 additions & 4 deletions codex-rs/network-proxy/src/mitm.rs
Original file line number Diff line number Diff line change
Expand Up @@ -52,6 +52,11 @@ pub struct MitmState {
max_body_bytes: usize,
}

pub(crate) struct MitmUpstreamConfig {
pub(crate) allow_upstream_proxy: bool,
pub(crate) allow_local_binding: bool,
}

#[derive(Clone)]
struct MitmPolicyContext {
target_host: String,
Expand Down Expand Up @@ -80,16 +85,16 @@ impl std::fmt::Debug for MitmState {
}

impl MitmState {
pub(crate) fn new(allow_upstream_proxy: bool) -> Result<Self> {
pub(crate) fn new(config: MitmUpstreamConfig) -> Result<Self> {
// MITM exists to make limited-mode HTTPS enforceable: once CONNECT is established, plain
// proxying would lose visibility into the inner HTTP request. We generate/load a local CA
// and issue per-host leaf certs so we can terminate TLS and apply policy.
let ca = ManagedMitmCa::load_or_create()?;

let upstream = if allow_upstream_proxy {
UpstreamClient::from_env_proxy()
let upstream = if config.allow_upstream_proxy {
UpstreamClient::from_env_proxy_with_allow_local_binding(config.allow_local_binding)
} else {
UpstreamClient::direct()
UpstreamClient::direct_with_allow_local_binding(config.allow_local_binding)
};

Ok(Self {
Expand Down
6 changes: 6 additions & 0 deletions codex-rs/network-proxy/src/runtime.rs
Original file line number Diff line number Diff line change
Expand Up @@ -532,6 +532,12 @@ impl NetworkProxyState {
Ok(guard.config.network.allow_upstream_proxy)
}

pub async fn allow_local_binding(&self) -> Result<bool> {
self.reload_if_needed().await?;
let guard = self.state.read().await;
Ok(guard.config.network.allow_local_binding)
}

pub async fn network_mode(&self) -> Result<NetworkMode> {
self.reload_if_needed().await?;
let guard = self.state.read().await;
Expand Down
8 changes: 4 additions & 4 deletions codex-rs/network-proxy/src/socks5.rs
Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
use crate::config::NetworkMode;
use crate::connect_policy::TargetCheckedTcpConnector;
use crate::network_policy::BlockDecisionAuditEventArgs;
use crate::network_policy::NetworkDecision;
use crate::network_policy::NetworkDecisionSource;
Expand Down Expand Up @@ -34,7 +35,6 @@ use rama_socks5::server::udp::RelayRequest;
use rama_socks5::server::udp::RelayResponse;
use rama_tcp::TcpStream;
use rama_tcp::client::Request as TcpRequest;
use rama_tcp::client::service::TcpConnector;
use rama_tcp::server::TcpListener;
use std::io;
use std::net::SocketAddr;
Expand Down Expand Up @@ -94,7 +94,7 @@ async fn run_socks5_with_listener(
}
}

let tcp_connector = TcpConnector::default();
let tcp_connector = TargetCheckedTcpConnector::new(state.clone());
let policy_tcp_connector = service_fn({
let policy_decider = policy_decider.clone();
move |req: TcpRequest| {
Expand Down Expand Up @@ -131,7 +131,7 @@ async fn run_socks5_with_listener(

async fn handle_socks5_tcp(
req: TcpRequest,
tcp_connector: TcpConnector,
tcp_connector: TargetCheckedTcpConnector,
policy_decider: Option<Arc<dyn NetworkPolicyDecider>>,
) -> Result<EstablishedClientConnection<TcpStream, TcpRequest>, BoxError> {
let app_state = req
Expand Down Expand Up @@ -548,7 +548,7 @@ mod tests {
let (result, events) = capture_events(|| async {
handle_socks5_tcp(
request,
TcpConnector::default(),
TargetCheckedTcpConnector::new(state.clone()),
/*policy_decider*/ None,
)
.await
Expand Down
8 changes: 5 additions & 3 deletions codex-rs/network-proxy/src/state.rs
Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,7 @@ use crate::config::NetworkMode;
use crate::config::NetworkProxyConfig;
use crate::config::NetworkUnixSocketPermissions;
use crate::mitm::MitmState;
use crate::mitm::MitmUpstreamConfig;
use crate::policy::DomainPattern;
use crate::policy::compile_allowlist_globset;
use crate::policy::compile_denylist_globset;
Expand Down Expand Up @@ -66,9 +67,10 @@ pub fn build_config_state(
let deny_set = compile_denylist_globset(&denied_domains)?;
let allow_set = compile_allowlist_globset(&allowed_domains)?;
let mitm = if config.network.mitm {
Some(Arc::new(MitmState::new(
config.network.allow_upstream_proxy,
)?))
Some(Arc::new(MitmState::new(MitmUpstreamConfig {
allow_upstream_proxy: config.network.allow_upstream_proxy,
allow_local_binding: config.network.allow_local_binding,
})?))
} else {
None
};
Expand Down
Loading
Loading