Techcle Wiki

Requirements

10 min read

Requirements Document: Secure Proxy (sec-proxy)

Introduction

The Secure Proxy (sec-proxy) is a security gateway that sits between internal infrastructure (Kubernetes clusters and build environments) and external package repositories. It provides centralized control, security scanning, and caching for all external dependencies including Docker images and packages from common package managers.

Glossary

  • Sec_Proxy: The secure proxy system that mediates access to external package repositories
  • Package_Manager: A software tool for managing dependencies (npm, pip, Maven, Go modules, etc.)
  • Docker_Registry: A repository for storing and distributing Docker container images
  • Build_Environment: Internal systems where software is compiled and built
  • Kubernetes_Cluster: Container orchestration platform running internal workloads
  • External_Repository: Third-party package sources (npmjs.com, pypi.org, Docker Hub, etc.)
  • Security_Scanner: Component that analyzes packages for vulnerabilities and malicious content
  • Cache_Layer: Local storage for previously fetched package metadata to improve performance and reduce upstream API calls
  • Access_Policy: Rules defining which packages and versions are allowed, including age thresholds and CVE severity limits
  • Rule_Exclusion: Configuration that exempts specific packages from certain rules
  • Package_Age: Time elapsed since a package version was published to its registry
  • Npm_Handler: Registry-specific implementation for npm package requests
  • Docker_Handler: Registry-specific implementation for Docker image requests
  • Pip_Handler: Registry-specific implementation for pip package requests
  • Maven_Handler: Registry-specific implementation for Maven artifact requests
  • Go_Handler: Registry-specific implementation for Go module requests
  • CVE_Database: External database of Common Vulnerabilities and Exposures
  • Version_Tag: Dynamic version identifier like “latest” that resolves to a specific version
  • Audit_Log: Record of all package requests and security decisions

Requirements

Requirement 1: Docker Image Proxying

User Story: As a Kubernetes administrator, I want to proxy Docker image pulls through sec-proxy, so that all container images are scanned and cached before deployment.

Acceptance Criteria

  1. WHEN a Kubernetes cluster requests a Docker image, THE Sec_Proxy SHALL intercept the request and fetch metadata from the External_Repository
  2. WHEN Docker image metadata is fetched, THE Sec_Proxy SHALL scan it for vulnerabilities before proxying the image to the client
  3. WHEN Docker image metadata passes security checks, THE Sec_Proxy SHALL cache the metadata in the Cache_Layer
  4. WHEN cached Docker image metadata is available, THE Sec_Proxy SHALL use it for policy evaluation without re-fetching
  5. IF a Docker image fails security scanning, THEN THE Sec_Proxy SHALL block the request and return an error to the client

Requirement 2: NPM Package Proxying

User Story: As a developer, I want to install npm packages through sec-proxy, so that JavaScript dependencies are validated before use.

Acceptance Criteria

  1. WHEN a build environment requests an npm package, THE Sec_Proxy SHALL intercept the request and fetch metadata from the External_Repository
  2. WHEN npm package metadata is fetched, THE Sec_Proxy SHALL validate package integrity using checksums
  3. WHEN npm package metadata passes validation, THE Sec_Proxy SHALL cache the metadata in the Cache_Layer
  4. WHEN cached npm package metadata is available, THE Sec_Proxy SHALL use it for policy evaluation without re-fetching
  5. IF an npm package fails integrity validation, THEN THE Sec_Proxy SHALL block the request and log the security violation

Requirement 3: Python Package Proxying

User Story: As a Python developer, I want to install pip packages through sec-proxy, so that Python dependencies are secured and available.

Acceptance Criteria

  1. WHEN a build environment requests a pip package, THE Sec_Proxy SHALL intercept the request and fetch metadata from the External_Repository
  2. WHEN pip package metadata is fetched, THE Sec_Proxy SHALL verify cryptographic signatures if available
  3. WHEN pip package metadata passes verification, THE Sec_Proxy SHALL cache the metadata in the Cache_Layer
  4. WHEN cached pip package metadata is available, THE Sec_Proxy SHALL use it for policy evaluation without re-fetching
  5. IF a pip package fails verification, THEN THE Sec_Proxy SHALL block the request and notify administrators

Requirement 4: Maven Package Proxying

User Story: As a Java developer, I want to fetch Maven artifacts through sec-proxy, so that Java dependencies are controlled and cached.

Acceptance Criteria

  1. WHEN a build environment requests a Maven artifact, THE Sec_Proxy SHALL intercept the request and fetch metadata from the External_Repository
  2. WHEN Maven artifact metadata is fetched, THE Sec_Proxy SHALL validate POM files and checksums
  3. WHEN Maven artifact metadata passes validation, THE Sec_Proxy SHALL cache the metadata in the Cache_Layer
  4. WHEN cached Maven artifact metadata is available, THE Sec_Proxy SHALL use it for policy evaluation without re-fetching
  5. IF a Maven artifact fails validation, THEN THE Sec_Proxy SHALL reject the request and log the failure

Requirement 5: Go Module Proxying

User Story: As a Go developer, I want to fetch Go modules through sec-proxy, so that Go dependencies are verified and available offline.

Acceptance Criteria

  1. WHEN a build environment requests a Go module, THE Sec_Proxy SHALL intercept the request and fetch metadata from the External_Repository
  2. WHEN Go module metadata is fetched, THE Sec_Proxy SHALL verify go.sum checksums
  3. WHEN Go module metadata passes verification, THE Sec_Proxy SHALL cache the metadata in the Cache_Layer
  4. WHEN cached Go module metadata is available, THE Sec_Proxy SHALL use it for policy evaluation without re-fetching
  5. IF a Go module fails checksum verification, THEN THE Sec_Proxy SHALL block the request and return an error

Requirement 6: YAML-Based Configuration

User Story: As a security administrator, I want to configure sec-proxy using YAML files with global and per-registry rules, so that policies can be version-controlled and easily managed.

Acceptance Criteria

  1. WHEN a YAML configuration file is provided, THE Sec_Proxy SHALL parse global rules and per-registry rules
  2. WHEN global rules are defined, THE Sec_Proxy SHALL apply them to all registries unless overridden
  3. WHEN per-registry rules are defined, THE Sec_Proxy SHALL apply them to specific registries, overriding global rules
  4. WHEN the configuration includes rule exclusions for specific packages, THE Sec_Proxy SHALL exempt those packages from the specified rules
  5. WHEN the configuration is invalid, THE Sec_Proxy SHALL report specific validation errors with line numbers

Requirement 7: Package Age-Based Filtering

User Story: As a security engineer, I want to block packages newer than a configurable age threshold, so that supply chain attacks targeting newly published packages are prevented.

Acceptance Criteria

  1. WHEN a package is requested, THE Sec_Proxy SHALL retrieve its publication timestamp from the registry metadata
  2. WHEN a package age is less than the configured minimum age threshold, THE Sec_Proxy SHALL block the request
  3. WHEN a package age meets or exceeds the minimum age threshold, THE Sec_Proxy SHALL allow the request to proceed
  4. WHEN a package has an exclusion configured, THE Sec_Proxy SHALL bypass age checks for that specific package
  5. WHEN age information is unavailable, THE Sec_Proxy SHALL apply the configured default action (block or allow)

Requirement 8: Version Resolution with Age Rules

User Story: As a developer, I want the proxy to automatically resolve version tags to compliant versions, so that my builds succeed while respecting security policies.

Acceptance Criteria

  1. WHEN a request uses a version tag like “latest”, THE Sec_Proxy SHALL retrieve all available versions from registry metadata
  2. WHEN evaluating versions against age rules, THE Sec_Proxy SHALL identify the newest version that meets the age threshold
  3. WHEN a compliant version is found, THE Sec_Proxy SHALL transparently return that version to the client
  4. WHEN no version meets the age threshold, THE Sec_Proxy SHALL block the request and return an error explaining the policy violation
  5. WHEN a specific version is requested, THE Sec_Proxy SHALL evaluate only that version against age rules

Requirement 9: Registry-Specific Rule Implementations

User Story: As a platform engineer, I want each registry type to have its own rule implementation, so that registry-specific behaviors are handled correctly.

Acceptance Criteria

  1. WHEN processing an npm request, THE Npm_Handler SHALL retrieve package metadata from the npm registry API
  2. WHEN processing a Docker request, THE Docker_Handler SHALL retrieve image metadata from the Docker registry API
  3. WHEN processing a pip request, THE Pip_Handler SHALL retrieve package metadata from the PyPI API
  4. WHEN processing a Maven request, THE Maven_Handler SHALL retrieve artifact metadata from the Maven repository
  5. WHEN processing a Go module request, THE Go_Handler SHALL retrieve module metadata from the Go proxy protocol

Requirement 10: CVE Integration and Vulnerability Assessment

User Story: As a security engineer, I want to check packages against CVE databases, so that known vulnerabilities are detected and blocked based on severity.

Acceptance Criteria

  1. WHEN a package is requested, THE Sec_Proxy SHALL query CVE databases for known vulnerabilities in that package version
  2. WHEN CVEs are found, THE Sec_Proxy SHALL evaluate their severity scores against configured thresholds
  3. WHEN critical or high-severity CVEs are found, THE Sec_Proxy SHALL block the package based on policy configuration
  4. WHEN low or medium-severity CVEs are found, THE Sec_Proxy SHALL log them and apply configured policy actions
  5. WHEN CVE data is unavailable, THE Sec_Proxy SHALL proceed based on configured fallback behavior

Requirement 11: Extensible Rule Framework

User Story: As a platform engineer, I want to add new rule types over time, so that the proxy can evolve with changing security requirements.

Acceptance Criteria

  1. WHEN a new rule type is implemented, THE Sec_Proxy SHALL support it through a common rule evaluation interface
  2. WHEN rules are evaluated, THE Sec_Proxy SHALL apply them in a configurable order
  3. WHEN multiple rules apply to a package, THE Sec_Proxy SHALL combine their results based on configured logic (AND/OR)
  4. WHEN a rule evaluation fails, THE Sec_Proxy SHALL log the failure and continue with remaining rules
  5. THE Sec_Proxy SHALL support adding custom rule implementations without modifying core proxy logic

Requirement 8: Audit Logging and Monitoring

User Story: As a compliance officer, I want comprehensive audit logs of all package requests, so that I can track dependency usage and security decisions.

Acceptance Criteria

  1. WHEN a package request is received, THE Sec_Proxy SHALL log the request details to the Audit_Log
  2. WHEN a security decision is made, THE Sec_Proxy SHALL log the decision, reasoning, and applicable rules to the Audit_Log
  3. WHEN a package is served from cache, THE Sec_Proxy SHALL log the cache hit to the Audit_Log
  4. WHEN a package is blocked, THE Sec_Proxy SHALL log the block reason, policy rule, and package age or CVE data to the Audit_Log
  5. THE Audit_Log SHALL include timestamps, client identity, package details, and security outcomes for all entries

Requirement 12: Cache Management

User Story: As a system administrator, I want to manage the metadata cache, so that memory is used efficiently and stale metadata is refreshed.

Acceptance Criteria

  1. WHEN the Cache_Layer reaches a configured entry limit, THE Sec_Proxy SHALL evict least-recently-used metadata entries
  2. WHEN metadata exceeds a configured TTL, THE Sec_Proxy SHALL mark it as stale and re-fetch on next request
  3. WHEN an administrator requests cache invalidation, THE Sec_Proxy SHALL remove specified metadata entries from the Cache_Layer
  4. WHEN cache statistics are requested, THE Sec_Proxy SHALL report hit rates, entry count, and memory usage
  5. THE Sec_Proxy SHALL persist cache metadata across restarts when using Redis backend

Requirement 13: High Availability and Performance

User Story: As a platform engineer, I want sec-proxy to be highly available and performant, so that it doesn’t become a bottleneck for builds and deployments.

Acceptance Criteria

  1. WHEN multiple Sec_Proxy instances are deployed, THE Sec_Proxy SHALL share metadata cache state across instances using Redis
  2. WHEN a metadata lookup is performed, THE Sec_Proxy SHALL respond within 100ms for cached metadata
  3. WHEN upstream repositories are unavailable, THE Sec_Proxy SHALL use cached metadata for policy evaluation if available
  4. WHEN concurrent requests arrive, THE Sec_Proxy SHALL handle at least 1000 requests per second per instance
  5. WHEN an instance fails, THE Sec_Proxy SHALL automatically route traffic to healthy instances

Requirement 14: Configuration and Administration

User Story: As a system administrator, I want to configure sec-proxy through declarative configuration files, so that settings can be version-controlled and automated.

Acceptance Criteria

  1. WHEN a configuration file is provided, THE Sec_Proxy SHALL parse and validate it on startup
  2. WHEN configuration is invalid, THE Sec_Proxy SHALL report specific validation errors and refuse to start
  3. WHEN configuration changes are detected, THE Sec_Proxy SHALL reload settings without dropping connections
  4. THE Sec_Proxy SHALL support configuration for upstream repositories, policies, cache settings, and security thresholds
  5. THE Sec_Proxy SHALL provide a health check endpoint that reports configuration status and system health

Graph View