Commit history in the core sapp DPI engine repo (MESA_Platform/sapp) shows its RST-style blocking/injection path is internally called "欺骗包" (literally "deceptive/spoofed packet") injection, implemented via a sapp_inject_ctrl_pkt function that sends forged control packets to all devices opened through the marsio packet-I/O layer; ticket TSG-20317 documents active, ongoing optimization of "inject packet duplicate traffic detection" performance in this code path as of 2024.
f77dcf1c603a9b2b518c76385be3487ab1d9f94a refactor(sapp_inject_ctrl_pkt): 重构实现,不再直接复用注欺骗包接口 (2023-09-18). 3b5b2bd42fa57f3044f4dd42f88ab80fd563a899 feat(sapp_inject_ctrl_data): 发送控制信息至所有用marsio打开的设备 (2023-11-16). 132e9473ff47e8d4f37479b6231fd2ec5948753a TSG-20317: 1.Optimize inject packet duplicate traffic detection performance (2024-04-02).
Defense implications
- RST/forged-control-packet injection ('spoofed packet' internally) is an actively-maintained, first-class code path in sapp, not a legacy feature — protocol designers should treat any unsolicited RST or malformed control-plane packet on a monitored link as a probable injection rather than a genuine peer signal, and design for resilience against duplicate/replayed injected packets specifically (an area sapp itself was still tuning as of TSG-20317).
Cited artifacts
mesalab_git—MESA_Platform/sapp.bundle(git-commit-log)
Provenance pointers only — no leak content is rehosted. Raw material: Enlace Hacktivista.
Related findings
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.
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.
A repo named "active-defense/houyi-deploy" is an Ansible playbook that installs a component called "houyi" (后羿) alongside sapp and a "wire-graft" packet-injection module (matching the taxonomy's marsio "wired_graft" plugin); the bundled RPMs/scripts include standalone binaries named tcp_syn_flood, udp_dns_flood, and a DNS-reflection-amplification script (reflect_dns.sh), indicating this TSG-adjacent platform includes offensive flooding/DDoS capability, not just passive blocking.
SAPP's internal developer manual documents three generic "packet-send" interfaces exposed to every business plugin: MESA_kill_tcp (builds and sends a TCP RST matching the current flow's four-tuple/sequence numbers to forcibly terminate a connection), MESA_kill_tcp_synack (sends a forged SYN/ACK so the client can never complete a handshake with the real server), and MESA_inject_pkt (injects arbitrary application-layer payload toward either side of a flow). This confirms RST-injection and payload-injection are first-class, reusable platform primitives, not one-off code, and that mrzcpd is the mechanism that re-injects sapp-generated blocking packets into a mirrored/passive-tap link (consistent with taxonomy.yaml's mrzcpd note).
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).
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.