Zero TrustDefense in DepthFail-Closed

Security

TDP implements defense in depth -- every layer independently verifies access. HMAC authentication, command filtering, security profiles, Active Directory integration, and manifest signing work together so that compromising one layer does not compromise the system.

Six layers of protection

Each layer operates independently. An attacker must defeat all six to execute an unauthorized tool call.

LAYER 01

HMAC-SHA256 Auth

Every connection cryptographically verified

LAYER 02

Command Filter

Blocks destructive shell commands before execution

LAYER 03

Security Profiles

Read-only, no-network, strict enforcement modes

LAYER 04

AD Group Enforcement

Active Directory group membership verification

LAYER 05

Manifest Signing

Only trusted server broadcasts are accepted

LAYER 06

Per-Agent Permissions

Each agent gets its own secret and tool access

HMAC-SHA256 Authentication

Every agent must prove its identity before accessing any tool. Per-agent secrets mean compromising one agent does not compromise others.

live demo -- hmac auth

256-bit secrets

Cryptographically random, per-agent

Challenge-response

Secrets never cross the wire

Env var required

TDP_SECRET must be set or server exits

Command Filter

A pre-tool-use hook that intercepts destructive commands across Bash, PowerShell, Shell, Terminal, Cmd, and MCP tool calls. Every blocked command is logged for audit.

live demo -- command filter

Blocked patterns include:

rm -rfmkfschmod 777chown -R rootdd if=format C:del /f /sStop-ServiceRemove-Item -Recurse

Security Profiles

Four enforcement modes that classify every tool call as read, write, or network. Switch profiles without restarting servers.

live demo -- profile enforcement
ProfileReadWriteNetwork
read-writeAllowedAllowedAllowed
read-onlyAllowedBlockedAllowed
no-networkAllowedAllowedBlocked
strictAllowedBlockedBlocked

Active Directory Group Enforcement

Server-level AD group verification before any tool executes. Prevents VM bypass attacks -- even with a valid HMAC key, users without the right AD group are denied.

live demo -- ad group check

Per-profile AD groups

read-write -- TDP-Users

read-only -- TDP-ReadOnly

strict -- TDP-Users

admin -- TDP-Admins

Design principles

Fail-closed: AD unreachable = denied

5-minute group cache (no AD hammering)

pywin32 native + LDAP3 cross-platform

Runs after HMAC (defense in depth)

Manifest Signing

Server broadcasts are signed with HMAC. Callers can be configured to only accept signed manifests, filtering out rogue servers on the network.

live demo -- manifest trust

VM Bypass Prevention

Even if an attacker spins up a VM and connects directly over TCP, multiple layers block unauthorized access. HMAC alone is not enough -- AD group enforcement catches leaked keys.

live demo -- vm bypass attack

Defense in depth means no single layer is a single point of failure. HMAC stops unknown agents. AD stops unauthorized users. Command filter stops destructive operations. Security profiles restrict tool categories. Manifest signing stops rogue servers. All six layers operate independently.

Built for teams that take security seriously

TDP gives AI agents access to tools without giving up control. Every connection is verified. Every command is filtered. Every action is logged.