A production feature spec ("加密协议JG") requires detection-and-control capability for QUIC, ESNI, and ECH, with a per-connection log field c_encrypt_type explicitly distinguishing ClientHello encryption (0=unencrypted, 1=ESNI, 2=ECH) and a DF_QUIC_REGION rule table matching QUIC by SNI. The system computes a per-rule "CT" (穿透/penetration) rate from paired mirror-vs-functional RST-packet logs (TF-RST-LOG / TF-MIRROR-RST-LOG) to grade each block rule's effectiveness, and runs continuous active-verification probes against its own rules, deliberately varying the probe 4-tuple each run "to ensure it doesn't hit the blacklist" so the verification traffic itself reaches the target.
c_encrypt_type INT ClientHello加密方式 0: 默认未加密 1：ESNI加密 2：ECH加密...主动验证四元组需要变化，以保证不命中黑名单
Defense implications
- This operator already distinguishes ECH from ESNI per-connection and measures blocking effectiveness against each separately -- do not assume ECH is treated as generic 'unclassifiable encrypted traffic'; its blocking status is being tracked and graded with its own bypass-rate metric.
- The self-verification harness (mirror-port + functional-port RST comparison, rotating probe 4-tuples) implies blocking rules are continuously health-checked in production -- a circumvention technique that only evades detection intermittently will likely be caught by this harness's own re-testing cadence.
Related findings
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').
An official "Geedge Networks Confidential And Proprietary" sapp/mrzcpd operations manual documents the packet-injection API (MESA_kill_tcp / MESA_inject_pkt) used for both out-of-band mirror-tap RST injection (relies on the local box's own IP routing table to send) and inline in-path injection (requires mrtunnat.conf tunnel-tracking state -- use_recent_tunnel, use_link_info_table -- keyed on outer/inner MAC and link_id/link_dir), plus the Marsio DPDK-based driver's I/O sub-modes (marsio4, marsio_vxlan, pag_marsio, agent_smith) and its role extracting VXLAN/GTP encapsulation metadata and stamping link/circuit identifiers into mirrored packets' MAC field for session-log correlation.
The same feature spec adds a "定向攻击检测" (targeted-attack detection) mechanism: the front-end tracks per-rule (configID) hit counts against a threshold/interval, and once exceeded can throttle or fully suppress emission of RST/block packets and logs for that rule (action codes include "do not send block packets," "sample block packets") -- an explicit rate-limiting countermeasure against the operator's own RST-injection infrastructure being weaponized for reflection/availability attacks, the same attack class (Bock et al., "Weaponizing middleboxes"; "Your censor is my censor") cited in this same lab's own literature survey (see companion finding 2026-mesa-censorship-research-survey-f8c349).
chongming/traffic_replay is a Flask/tcpreplay-based QA harness that replays curated pcaps against a TSG instance to exercise its decoders, including SSL fixtures specifically named ssl_ech_false.pcap, ssl_no_sni.pcap and ssl_tls13.pcap alongside esni.pcap, openvpn.pcap, and major-platform captures (facebook/google/twitter/ youtube). A companion update_tsg_ca.py/tsg_ca.txt installs a TSG-issued CA cert on the test client, confirming the QA environment exercises TLS interception as part of routine detection testing.
Two independently-leaked TSG session-log CSV exports share an identical 224-field schema whose proxy_* columns (proxy_action, proxy_pinning_status, proxy_intercept_status, proxy_cert_verify, proxy_intercept_error) log the outcome of TLS interception per session, alongside ssl_ja3_hash/ssl_ja3s_hash, ssl_esni_flag, ssl_ech_flag, and quic_sni fields — confirming MITM/cert-pinning-bypass instrumentation and TLS/QUIC fingerprinting are built into TSG's standard traffic-logging pipeline, not a bolt-on feature.
A TSG-Application blocklist test found that disabling Facebook/Twitter in TSG's per-app policy did not stop Psiphon3 traffic from reaching those services in practice, because Psiphon3's dual-stack fallback drove the tunneled Facebook traffic over IPv4 QUIC, which TSG's classifier failed to attribute to Facebook -- in contrast to Taobao/Bilibili/Youku/JD, which TSG blocked successfully in the same test.