traffic-capture

name	traffic-capture
description	Working on the HTTP capture proxy and its replay/fuzz path: the egress guard that stops the proxy becoming an SSRF pivot, why it checks the resolved IP, and keeping capture off the scan's critical path. Trigger: editing scanners/capture_proxy/ (capture_addon.py, egress.py, ingest_worker.py); adding a forward/replay/fuzz path; changing EgressPolicy or the internal denylist; wiring an agent tool that replays captured traffic.
license	MIT
metadata	{"author":"redamon","version":"1.0.0","scope":["capture_proxy"],"auto_invoke":["Editing the capture proxy, egress guard, or replay/fuzz path"]}

When to Use

• Changing how the proxy forwards, captures, ingests, or replays traffic.

The one-line "route every egress through the guard" rule is in the capture_proxy AGENTS.md CRITICAL RULES; this skill is the mechanism.

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Critical Rules

• NEVER match the internal denylist on the hostname alone. The guard denies on the resolved IP (RFC1918 and friends), because a hostname that resolves to an internal address (or re-resolves after a check) is the SSRF/DNS-rebinding case. See scanners/capture_proxy/egress.py (the block conditions operate on the resolved IP).
• NEVER build a replay/fuzz target from unvalidated LLM output and send it straight out. The replay path is a new egress path; it must pass the same EgressPolicy guard as captured traffic, or the agent can be steered into an internal pivot. Args must not reach the wire un-guarded.
• NEVER remove a block condition to "make replay work". Each condition is individually toggleable via EgressPolicy (surfaced in settings); loosen it there, per-condition, not by deleting the check.
• ALWAYS keep capture and ingest off the scan's critical path. Capture writes an append-only spool; a separate worker tails it into Postgres (scanners/capture_proxy/ingest_worker.py). That decoupling is deliberate - capture must never block or slow the scan it observes.

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The capture pipeline

Stage	File	Note
intercept	capture_addon.py	mitmproxy addon; request/response hooks
egress guard	egress.py	resolved-IP denylist + EgressPolicy toggles; the SSRF backstop
ingest	ingest_worker.py	tails the spool -> Postgres; off the scan path

Commands

docker compose --profile tools build capture-proxy    # image rebuild (Dockerfile change)
./redamon.sh test unit                                # capture_proxy section

Resources

• docs/readmes/README.TRAFFIC.md - capture/replay/fuzz architecture and settings
• Related: capture_proxy AGENTS.md CRITICAL RULES (route egress through the guard)