This CoreDNS-fork DNS server was built by a MESA Lab/IIE engineer (name/email redacted) that bundles a "prober" active-probing plugin, a "v64dns" module, and an "atk" plugin with dedicated branches (atk_DDoS, atk_DDoS_resolver, atk_qp) implementing DNS response amplification and an attempted DNS injection/tampering feature ("注入篡改功能实现尝试"). This combines active DNS probing with resolver-based amplification/attack tooling in one codebase.

A MESA Lab repo (shihaoyue/yy_deploy_script) contains an organized suite of active attack tooling specifically targeting encrypted DNS: DoH/DoT downgrade attacks, DoH/DoT DDoS including a CVE-2024-4487 (HTTP/2 Rapid Reset) exploit script, IPv6 DNS response spoofing/injection (fakedns6 using forged-source-address "saddns"), a DNSSEC-downgrade proxy, DNSSEC-DDoS tooling, and an active DNS-fingerprinting probe pair (fpdns_client/fpdns_server under a folder named "TargetGZ"). This is direct evidence of GFW-adjacent R&D that specifically attacks the encrypted-DNS protocols (DoH/DoT) circumvention tools often rely on for resolver privacy.

An internal MESA Lab presentation by a MESA Lab researcher (name/email redacted) describes 'CartoDNS', a global active/passive encrypted-DNS reconnaissance system that uses DNS-watermark injection across multi-region probing nodes to map DoT/DoH/DoQ resolver topology; as of the presentation it had discovered 80,000+ DoT, 20,000+ DoH and 4,000+ DoQ IPv4 resolvers (plus 1,100+ DoT and 500+ DoH over IPv6) and cataloged 500+ service providers with concrete IP ranges (Cloudflare, Google, Quad9, AdGuard, 360, Alibaba, Tencent, etc.), running continuously since December 2021.

An internal TSG functional-requirements spec ('加密协议JG') defines device support for identifying and blocking ECH, ESNI and QUIC traffic via per-connection SNI/region-matching tables (e.g. DF_QUIC_REGION), plus a companion 'FD报文全流程感知' feature that both passively monitors and actively injects synthetic verification traffic end-to-end through the network path to compute a live per-rule 'CT率' (breakthrough/penetration rate) — the system self-measures how often its own QUIC/ESNI/ECH blocks fail to take effect, and separately throttles logging/blocking detail for rule IDs receiving unusually high hit counts (DF_ATTACK_PROTECTION, 'targeted attack detection').

Raw structured DNS event logs (dated 2021-08-23) captured from what appears to be a GFW-adjacent DNS monitoring/injection pipeline use a schema purpose-built for DNS response forgery ('CHEAT_TYPE', 'CHEAT_RCODE', 'CHEAT_STRATEGY', 'CHEAT_RR', 'INJECTED_PKT_FILE' fields) alongside per-query geolocation; sampled records show lookups for facebook.com and tiktokv.com originating from residential China Telecom/Unicom/Mobile subscriber IPs in Guangdong, Zhejiang, Anhui and other provinces, resolving against both domestic and foreign (8.8.8.8, OpenDNS) resolvers.

A WWW 2024 paper co-authored by MESA Lab's PI (MESA Lab PI, IIE-CAS (name redacted)) presents VPNChecker, a graph-based active-probing VPN-server detector modeling cross-port probe-response behavior; the paper states VPNChecker was deployed and evaluated inside a real ISP's network as a complement to existing detection engines, and documents concrete multi-port active-probing signatures for many commercial VPN/circumvention tools (e.g. Psiphon3: {22,53,443}, {22,443,554}, {22,53,443,554}).

A 2023 MESA Lab monthly report describes the 'TF' project's active-defense work: test cases for serial ('串联') HTTP hijack/tamper and parallel ('并联') DNS race-injection ('DNS抢答'), performance tuning that scaled active-defense capacity from 3 to 5 units, converting two existing TSG boxes to active-defense mode, and rewriting the active-defense flow-control logic to no longer depend on sapp.