dsh-plugin-gate

Installation safety gate for DeepSeek Harness plugins — an antivirus-style review step before you run dsh plugin add.

The plugin marketplace is growing fast (thousands of entries), and malicious code mixed into a plugin is only a matter of time. dsh-plugin-gate gives the agent a gate_scan tool that inspects a plugin source — a local directory or an npm tarball — for the classic malware shapes:

Domain	What it checks
Scripts	npm lifecycle scripts (pre/install/postinstall), exec/spawn/shell:true, curl
Obfuscation	eval / new Function / vm.runIn*, hex-escape floods, base64 blobs, char-array packing
Permissions	credential env reads (OPENAI_API_KEY etc.), ssh/aws/npmrc file reads, writes to system/home/dotfile paths, chmod 777, sandbox-escalation requests
Network	external URLs & hosts, fetch/axios/socket/WebSocket/DNS APIs, cloud-metadata endpoints (169.254.169.254), Discord/Telegram/Slack webhooks, .onion, read-then-send exfiltration shape
Secrets	hardcoded sk- keys, ghp_ tokens, AWS keys, private key blocks, bearer tokens
Supply chain	exact-version direct dependencies checked against Google OSV (ranges and official @deepseek-ai packages skipped; configurable, offline-degrades)

The gate is read-only: it never executes scanned code and never writes files.

Install

In your DSH profile:

dsh plugin --profile <profile> add dsh-plugin-gate
# or add the bundle patch manually:
#   dsh --profile <profile> --patch ./node_modules/dsh-plugin-gate/cordis.patch.yml

Usage

Ask the agent to scan a plugin before installing it (the plugin also injects prompt guidance that tells the agent to do this automatically):

gate_scan target: "npm:dsh-plugin-some-package"
gate_scan target: "npm:dsh-plugin-some-package@1.2.3"   # pinned version
gate_scan target: "./downloaded-plugin"                 # local directory

Result shape:

{
  "verdict": "BLOCK" | "WARN" | "PASS",
  "score": 254,
  "summary": { "high": 0, "medium": 1, "low": 3, "categories": { "network": 4 } },
  "network": { "hosts": [...], "unallowlisted": [...], "readAndSendFiles": [...] },
  "hits": [{ "rule": "fetch_call", "category": "network", "severity": "medium",
             "file": "lib/index.js", "line": 12, "evidence": "...", "hint": "..." }],
  "recommendations": [...]
}

Verdict semantics

• BLOCK — at least one high-severity signature. Do not install until the maintainer ships a clean rebuild you can scan again.
• WARN — medium-severity patterns that need manual review (network I/O, home-path writes, base64 blobs). Inspect every hit in context.
• PASS — no risky signatures. Heuristic only — keep normal caution with unknown maintainers.

Context-aware rules: exec()/execSync() hits are downgraded when the file does not import child_process (typical RegExp#exec false positive); code-context rules (exec, eval, curl|sh, PowerShell…) are downgraded to low when found in comments or documentation (examples, not behavior) — while secrets and webhooks stay flagged even in comments. Dependencies installed from git/http/file URLs are flagged as risky_dependency, and >4000-char minified lines as minified_line (low).

Configuration

Key	Default	Meaning
maxFiles	1000	hard cap on scanned files per directory walk
maxFileBytes	2 MiB	per-file text cap
includeNodeModules	false	descend into node_modules
maxTarballBytes	32 MiB	npm tarball download cap
allowlistHosts	[]	hosts never listed as unallowlisted
osvCheck	true	query Google OSV for known vulnerabilities on exact-version deps
osvMaxDeps	8	max exact-version direct deps checked
osvTimeoutMs	10000	per-dep OSV query timeout
promptSection	true	inject agent guidance
sectionOrder	5	prompt section order

Development

node --check lib/*.js
node test/rules.test.mjs   # main-module mode (node --test is blocked in the DSH sandbox)
node test/scan.test.mjs

Pure logic lives in lib/rules.js (signatures), lib/targz.js (in-memory tar.gz), lib/scan.js (orchestration + verdict). The Cordis plugin is lib/index.js.

Security

The gate never executes scanned content. It is a heuristic signature scanner — it can miss novel malware and over-flag innocent code. Review BLOCK/WARN hits yourself; see SECURITY.md.

License

MIT