Architecture Overview
Architecture Overview
Section titled “Architecture Overview”QCecuring Code Signing is built on a secure, scalable, and modular architecture designed for enterprise governance and high-volume signing operations.
This document provides a high-level overview of system components and security boundaries.
High-Level Architecture
Section titled “High-Level Architecture”┌──────────────────────────────────────────────────────────────┐│ Client Layer ││ ││ jarsigner signtool OpenSSL cosign CI/CD Pipelines │└──────────────────────────────────────────────────────────────┘ │ ▼┌──────────────────────────────────────────────────────────────┐│ PKCS#11 / KSP Integration │└──────────────────────────────────────────────────────────────┘ │ ▼┌──────────────────────────────────────────────────────────────┐│ Signing Agent ││ (mTLS-secured communication) │└──────────────────────────────────────────────────────────────┘ │ │ mTLS / HTTPS ▼┌──────────────────────────────────────────────────────────────┐│ API Layer ││ - Authentication ││ - Authorization ││ - Request Validation │└──────────────────────────────────────────────────────────────┘ │ ▼┌──────────────────────────────────────────────────────────────┐│ Policy Engine ││ - Role-Based Access Control ││ - Approval Workflows ││ - Certificate & Time Restrictions │└──────────────────────────────────────────────────────────────┘ │ ▼┌──────────────────────────────────────────────────────────────┐│ Signing Engine ││ - Digest-Based Signing ││ - Sync / Async Processing ││ - Audit Event Generation │└──────────────────────────────────────────────────────────────┘ │ ▼┌──────────────────────────────────────────────────────────────┐│ HSM / KMS Abstraction Layer ││ - On-Prem HSM (PKCS#11) ││ - Cloud KMS Providers ││ - Secure Key Isolation │└──────────────────────────────────────────────────────────────┘ │ ▼┌──────────────────────────────────────────────────────────────┐│ Data Layer ││ ││ ┌──────────────┐ ┌──────────────┐ ┌──────────────┐ ││ │ Database │ │ Queue System │ │ Cache Layer │ ││ │ (Metadata) │ │ (Async Jobs) │ │ (Performance)│ ││ └──────────────┘ └──────────────┘ └──────────────┘ ││ ││ Audit & Archive Store │└──────────────────────────────────────────────────────────────┘Core Components
Section titled “Core Components”API Layer
Section titled “API Layer”The API layer:
- Accepts signing requests
- Authenticates users and agents
- Enforces authorization rules
- Routes requests for processing
It is stateless and horizontally scalable.
Policy Engine
Section titled “Policy Engine”Every signing request passes through policy evaluation:
- Role-based access control
- Certificate restrictions
- Application restrictions
- Time-based rules
- Optional approval workflows
If policy conditions are not satisfied, the signing request is denied.
Signing Engine
Section titled “Signing Engine”The signing engine:
- Processes digest-based signing requests
- Communicates with the HSM abstraction layer
- Handles synchronous and asynchronous workflows
- Generates audit records for each operation
Only cryptographic digests are signed — full artifacts are never transmitted.
HSM Abstraction Layer
Section titled “HSM Abstraction Layer”Keys are stored in secure environments:
- On-prem Hardware Security Modules
- Cloud Key Management Services
- PKCS#11-compatible providers
Private keys never leave the secure boundary.
All signing operations occur within the protected key store.
Distributed Agent Architecture
Section titled “Distributed Agent Architecture”For native tool integration:
- Linux systems use PKCS#11 providers
- Windows systems use KSP providers
- Agents communicate securely via mTLS
- Signing occurs without exposing private keys
This enables seamless integration with:
- jarsigner
- signtool
- OpenSSL
- CI/CD pipelines
Queue & Processing Layer
Section titled “Queue & Processing Layer”For high-volume environments:
- Signing requests can be processed asynchronously
- Workers scale horizontally
- Retry and error handling mechanisms ensure reliability
This enables enterprise-scale throughput.
Data & Audit Layer
Section titled “Data & Audit Layer”The platform maintains:
- Key metadata
- Certificate records
- Signing request history
- Policy configurations
- Complete audit logs
Audit logs provide:
- Immutable operation history
- Forensic traceability
- Compliance reporting support
Security Model
Section titled “Security Model”The platform enforces strong security boundaries:
Digest-Only Signing
Section titled “Digest-Only Signing”- Files remain on developer machines
- Only hashes are transmitted for signing
Hardware-Backed Key Protection
Section titled “Hardware-Backed Key Protection”- Keys never leave the HSM or secure KMS
- Export operations are restricted
- All key operations are audited
Authentication & Authorization
Section titled “Authentication & Authorization”- JWT-based user authentication
- mTLS-based agent authentication
- Role-based and policy-driven authorization
Audit & Compliance
Section titled “Audit & Compliance”Every operation is logged:
- Signing events
- Key lifecycle events
- Policy decisions
- Administrative actions
This supports regulatory and internal compliance requirements.
Scalability Model
Section titled “Scalability Model”The platform supports:
- Horizontal API scaling
- Distributed worker scaling
- High-availability deployments
- Kubernetes-native environments
- Cloud or on-prem infrastructure
It is designed for both mid-size teams and enterprise-scale environments.
Deployment Models
Section titled “Deployment Models”- Single-node evaluation setup
- High-availability production deployment
- Kubernetes cluster deployment
- Hybrid cloud / on-prem HSM environments