PanGu defines explicit business/service IDs for webpage keyword blocking (0x28) and keyword monitoring (0x98), with a dedicated NTC_KEYWORDS_URL_LOG log table storing the URLs recovered from keyword-hit traffic -- confirming keyword-based content filtering is a named, first-class TSG business rule with its own audit log, separate from domain/IP/SNI blocking.
新增ServiceID： 0x28 网页关键字阻断 0x98 网页关键字监测 ... 增加NTC_KEYWORDS_URL_LOG日志
Defense implications
- Keyword filtering here operates on decoded URL/page content (logged into NTC_KEYWORDS_URL_LOG), reinforcing that full-session encryption -- not just SNI/domain hiding -- is required to defeat this class of censor.
Cited artifacts
mesalab_git—PanGu/PanGu_docs.bundle(git-commit-log)
Provenance pointers only — no leak content is rehosted. Raw material: Enlace Hacktivista.
Related findings
A crash/perf bug report reveals Geedge's MAAT rule engine (libmaatframe.so, using Intel Hyperscan for literal/regex matching) running with 545,441 FQDN blocking rules and 404,141 IP address blocking rules loaded in a single instance as of 2024; loading 500,000 new FQDN rules via the full Hyperscan path took ~95 minutes, addressed by an automatic fallback to a second engine ("Rulescan") above 50,000 rules.
Geedge fingerprinted several V2Ray-based VPN apps by their fixed API/bootstrap domains rather than protocol characteristics — blocking "V2 Pro" via pro.mucacherry.org, "V2 VPN" via v2.mucacherry.org, and "V2Net VPN" via api.v2net.live plus 5 rotating free-node domains (free1-5.v2n3t2.online / v2n3t.online) the app uses to fetch node lists.
Geedge runs an ongoing, largely manual weekly signature-extraction program against commercial VPN apps (LetsVPN, Betternet, VPNLITE, and a ~80-app batch), combining server-IP lists, FQDN patterns, and payload/SNI/Host/User-Agent signatures, tested for blocking efficacy and false-positive rate before rollout. VPNLITE was fingerprinted via TCP direct-connect on ports 18000/3320/8099 plus TLS to randomized .xyz/.info subdomains on Cloudflare ranges (104.21.0.0/16, 172.67.0.0/16).
The internal 'MAAT网络流处理配置统一描述框架' engineering manual (v3.1.20, author 郑超, 2021) documents MAAT's Redis-synced rule-compilation framework and its RuleScan/Hyperscan-based pattern-matching engine (libmaatframe.so / librulescan), and records that RuleScan's fast-scan feature caused a production outage on 2019-03-19 and has been disabled ever since.
TSG/CM ships with pre-built, first-class 'Learning Object' entries specifically for Freegate (Object ID 18) and Psiphon3 (Object ID 19), plus a generic 'Top Server IP' object (ID 20) -- default product features, not customer-commissioned custom signatures. The Psiphon3 object auto-learns and dynamically updates a live blocklist that reached roughly 70,000 IPs at one deployment before a database issue temporarily dropped it to ~50,000.
Crash-dump stack traces reveal TSG's core packet-processing engine (sapp) architecture: a custom multi-threaded C engine using 'marsio' as the DPDK-style packet-I/O driver, a plugin system for protocol handlers (confirmed: plug/protocol/http/http.so), and a libdocumentanalyze component that actively decompresses gzip content and parses ZIP/document formats found inside HTTP bodies -- i.e. inspection goes beyond headers into reconstructed application content.