The same T1/NTC node config (ntcconf/t1conf/main.conf, K18/Astana/Kazakhtelecom) exposes concrete DPI enforcement toggles: a SYNACK_OR_RST switch and SEND_INJECT_PKT flag governing active TCP-response/packet-injection behavior; ASN- and IP-based blocklists (ASN_MAAT, IPD_DYN_MAAT, IPD_STATIC_MAAT) refreshed from MAAT/Redis on a 1-second effect interval; a dynamic blacklist with a 180s timeout; explicit protocol-blocking switches for BitTorrent (DHT/uTP) and eMule (Kad); and TLS metadata harvesting including certificate SAN fields (NTC_SSL_COLLECT, collect_san_sw=1) streamed to a Kafka topic.
[SYSTEM] SYNACK_OR_RST=1 SEND_INJECT_PKT=0 DYN_BLACKLIST_OPEN=1 DYN_BLACKLIST_TIMEOUT=180 ... [P2P] bt_dht_switch=1 bt_utp_switch=1 emule_kad_switch=1 ... [NTC_SSL_COLLECT] collect_all_sw=1 collect_san_sw=1 kafka_topic=NTC-COLLECT-SSL-LOG ... [ASN_MAAT]/[IPD_DYN_MAAT]/[IPD_STATIC_MAAT] EFFECT_INTERVAL_S=1
Defense implications
- A SYNACK_OR_RST toggle confirms this gateway class can choose between injecting a RST or completing a fake SYN-ACK for classified flows — treat unexpected RSTs and connections that stall post-handshake as possible active interference, not just packet loss, when diagnosing blocking in this region.
- TLS certificate SAN fields are harvested at scale (collect_san_sw=1) — avoid reusing one TLS certificate's SAN list across many circumvention endpoints, since SAN reuse becomes a trivial correlation key for the censor.
- ASN/IP blocklists refresh on a 1-second MAAT cycle — infrastructure IP rotation needs a turnaround faster than that to gain any real window of unblocked availability once fingerprinted.
- BitTorrent/eMule get dedicated, protocol-specific detection switches distinct from generic keyword/IP rules — a P2P-mimicking pluggable transport should not assume 'looks like generic UDP' is enough to avoid this classification path.
Cited artifacts
mesalab_git—PanGu/mesa_plug.bundle(git-commit-log)
Provenance pointers only — no leak content is rehosted. Raw material: Enlace Hacktivista.
Related findings
An internal TSG operations/troubleshooting manual lays out TSG's full traffic pipeline (NIC -> mrzcpd/marsio capture driver -> sapp DPI engine -> firewall/proxy(KNI->TFE)/active-defense/WAN-NAT policy branches) and shows engineers using maat_redis_tool to pull the live Redis-synced blocking policy tables (TSG_SECURITY_COMPILE, TSG_OBJ_IP_ADDR, TSG_OBJ_APP_ID) and filter them by numeric policy/object ID to debug why a block rule isn't firing.
The GitLab group itself is named "K18_NTCS_WEB" (K18 = Kazakhstan), and its "nfs" web app implements per-protocol keyword-filter configuration classes (App/FTP/Mail/P2P/SSL keyword configs), an OpenVPN IP-list config, RADIUS-based logging/reporting entities, MAAT rule-sync beans, and an explicit "IP spoofing" business feature with its own "PXY仿冒地址池" (proxy spoofed-address pool) and dedicated policy-log support -- the single strongest piece of evidence in this batch tying named keyword-filtering plus IP-spoofing capabilities directly to the Kazakhstan deployment.
Primary-source MESA Lab wiki documentation confirms SAPP ("Stream Analyse Process Platform") is a plugin-based traffic-inspection engine achieving 10-40Gbps per hardware unit, deployable either inline (串联) or as a passive mirror tap (并联), and exposes core platform APIs available to any business-layer plugin for forging a TCP RST (MESA_kill_tcp), spoofing a fake SYN/ACK to block connection establishment (MESA_kill_tcp_synack), and injecting arbitrary application-layer data into an established flow (MESA_inject_pkt).
"stellar" (git.mesalab.cn / geedgenetworks.com) is a C++ core DPI packet-processing engine with protocol decoders (HTTP, FTP, mail, QUIC, RTP, SIP, DTLS, SSL, DNS, SOCKS, stratum) and a dedicated packet-injection module (src/stellar/inject.cpp) with an extensive TCP-RST-injection test suite covering injection timed after SYN, SYN-ACK, first C2S payload, and sub-ACK. It integrates the MAAT rule engine (security_enforcer.cpp / scanner_maat.c, "Security enforcer maat plugin table"), the Marsio packet-I/O framework (marsio_io.cpp), and glimpse_detector as an integrated decoder plugin ("integration glimpse_detector", "rename to lpi plugin").
Geedge's production inline-deployment container bundle (tango/tsg_container) wires mrzcpd (capture/inject), sapp (DPI via maat rules), and a third component "tfe" (traffic-forwarding engine) together via Docker Compose; tfe ships a dedicated doh.conf (DNS-over-HTTPS handling) and the firewall-mode container's sapp config includes a send_raw_pkt.conf, a KNI (kernel network interface) config, an "asymmetric_presence_layer.conf" for mirror/asymmetric-routing deployments, and a "pangu" proxy module (pangu_pxy.conf / pangu_http.json).
Live TSG session logs from an internal test bed (device 21426003 / XXG-TSG-BJ) show active Deny actions firing against named commercial VPN apps -- Super Unlimited VPN, BetternetVPN, TouchVPN, LetsVPN -- via dated signature patches (e.g. BetternetVPN_Patch01_20240812 through Patch06_20240920, SuperUnlimitedVPN_Patch05 through Patch10 within six weeks), and LetsVPN's block fires on a JA3 TLS fingerprint (LetsVPN_by_ja3) even when the SNI/Host is spoofed to www.bytedance.com.