Review found `127.0.0.2` routed through the proxy. The bypass list carries four
literal loopback entries because that is all a consumer reading an environment
can match, and `proxyForUrl` matched only those — leaving the rest of
`127.0.0.0/8`, `0.0.0.0`, and the IPv4-mapped spellings routed through a proxy
that could then reach them. Loopback is now recognised structurally, which a
list entry cannot express; the published entries stay for the environment
readers.
The same review case exposed a wider one. `web_fetch` skips its address checks
on a proxied hop, because the proxy resolves the origin — but a literal needs no
resolution, so the skip bought nothing and let a proxy on this machine reach
every private range those checks refuse, `169.254.169.254` included. A literal
the checks would refuse now takes the validated path, where the existing
refusal already covers it.
Tests that proved a tunnelled hop used a loopback origin, which no policy can
route through a proxy any more. They name a host only the proxy can answer for
instead — closer to what a proxied request actually looks like.
The user guide promised the proxy carried every outbound request including
telemetry. It carries neither on an older Node, nor anything a model-authored
script sends, so the promise is narrowed and the exceptions listed. A password
in a proxy URL reaching every tool DSH runs is documented there too: it is how
the variable already behaves, and worth knowing before putting one in.
Second review pass on the outbound proxy work.
The installed dispatcher was undici's EnvHttpProxyAgent, which reuses the HTTP
proxy for `https:` whenever no HTTPS proxy is present. That is exactly the state
this package resolves after refusing a SOCKS or malformed URL the user named for
`https:`, so the scheme the diagnostic reported as direct was tunnelled anyway.
The dispatcher is now an Agent whose per-origin factory calls `proxyForUrl`, so
routing and `proxyForUrl` cannot disagree by parsing the same list twice.
`childProxyEnv` returned only the names the user exported, which left a child
Node direct whenever the proxy came from `ALL_PROXY` or from cordis.yml — Node's
`NODE_USE_ENV_PROXY` reads neither — and stripped the merged loopback bypass so
the child sent its own localhost traffic to the proxy. A scheme the user named
in either casing still reaches the child exactly as written; one they named in
neither now carries the resolved value, and the bypass list is always the merged
one.
A nested install (the plugin mounted over the launcher's policy) recorded the
outer policy's published values as the user's, then cleared the record on
disposal, so every later child inherited the normalization instead. The record
now belongs to the outermost install and is restored, not dropped.
`web_fetch` read the active policy twice — once to skip address pinning, again
inside the transport — so a disposal landing between the two reads produced an
unpinned direct connection to a host nothing validated. One snapshot now decides
both.
Also: the node:http proxy test asserted a route the engines range does not always
have, and the gate could not see undici bound through `await import('undici')`,
the form this repository actually uses.
Node's built-in fetch ignores HTTP_PROXY, so every harness request connected
directly regardless of what the user exported. Resolve one policy from the
launch environment and install it as undici's global dispatcher, then wire the
four surfaces a global dispatcher cannot reach: web_fetch's pinned transport,
the OTLP exporter's node:http agent, the E2B SDK's own proxy option, and the
environment a child process or worker thread is given.
Each outbound call site carries an egress test that drives its real code path
through a fake proxy; that measurement is what found the OTLP and E2B gaps.
Yichen Jiang