[mikemikimike]

Summary

fetch_url() allowed agent-directed requests to cloud metadata and private services. This PR validates DNS results before connecting and rechecks every redirect.

Changes

• Restrict URLs to HTTP(S), reject credentials, and block non-public addresses, including private IPv4 values embedded in IPv6.
• Pin connections to validated public IPs while preserving the original Host and HTTPS SNI; ignore environment proxy settings.
• Revalidate redirect targets, cap redirects at five, and fall back only to another validated address after a connection error or timeout.

Tests

• python -m pytest tests/test_phase11.py -k fetch_url -v --tb=short
• python -m pytest tests/ -v --tb=short on Python 3.12 and 3.13: 842 passed, 1 skipped (the optional notebook suite requires nbformat).
• python -m ruff check devagent/ tests/
• python -m build
• git diff --check

Compatibility / Known limitations

ruff format --check reports formatting differences that are also present in the unmodified baseline; no formatting-only changes are included. The repository CI workflow does not run this formatter check. mypy passes for devagent/tools/web_tools.py; checking the test module reports 9 pre-existing attribute errors because the Web Search test helpers are annotated as object.

Fixes #101: #101

[knight22-21]

Thanks for the fix, @mikemikimike! Pinning connections to validated public IPs, blocking non-public ranges, and re-validating redirect hops thoroughly addresses the SSRF vulnerability in \etch_url.

If you find DevAgent useful, a ⭐ on the repo would mean a lot — no pressure though!