fix(security): block MCP tools for quarantined skills (#1876)#1892
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fix(security): block MCP tools for quarantined skills (#1876)#1892
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Add two-layer enforcement to TrustGateExecutor so that Quarantined skills
cannot use MCP tools to bypass QUARANTINE_DENIED restrictions:
1. is_quarantine_denied() — exact match + _{entry} suffix match against the
static QUARANTINE_DENIED list (defence-in-depth for MCP-wrapped natives)
2. mcp_tool_ids registry — Arc<RwLock<HashSet<String>>> populated at startup
with all registered MCP tool sanitized IDs; Quarantined skills are denied
access to any tool in this set regardless of its name
Both check_trust() and execute_tool_call_confirmed() enforce the combined
predicate: is_quarantine_denied(id) || self.is_mcp_tool(id).
runner.rs populates the registry after MCP servers connect, covering tools
like filesystem_write_file, shell_execute, and docker_container_exec that
had no suffix match in QUARANTINE_DENIED.
Closes #1876
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Summary
QUARANTINE_DENIEDinTrustGateExecutoronly matched native tool IDs; MCP tools with server-prefixed IDs (e.g.filesystem_write_file,shell_execute,docker_container_exec) bypassed all quarantine restrictionsmcp_tool_ids: Arc<RwLock<HashSet<String>>>registry toTrustGateExecutor— populated at startup with all registered MCP tool sanitized IDsis_quarantine_denied()with exact + suffix matching as defence-in-depth for MCP-wrapped native tool namescheck_trust()andexecute_tool_call_confirmed()now enforce:is_quarantine_denied(id) || self.is_mcp_tool(id)runner.rspopulates the registry after MCP servers connectTest plan
cargo nextest run --config-file .github/nextest.toml --workspace --features full --lib --binsgithub_run_command,shell_execute,docker_container_execare blocked for Quarantined skillsfilesystem_write_fileblocked via registry even though it has no suffix matchread,filesystem_read_file) remain allowed for Quarantined skillscargo +nightly fmt --checkcleancargo clippy --workspace --features full -- -D warningscleanCloses #1876