MetaMUI Crypto Primitives Security Procedures

Side-channel claim limit. Nothing on this page claims constant-time behaviour or side-channel resistance for any target: the side-channel harness covers nothing (finding A48) and no measurement exists. The Rust and C cores are designed for constant time and unmeasured; managed runtimes (JIT, GC, bounds checks) make no timing claim. Where this page names constant-time or side-channel techniques, in prose or in code, they are design intent or recommendations, not measured properties.

Table of Contents

1. Secure Development Procedures
2. Key Management Procedures
3. Security Testing Procedures
4. Incident Response Procedures
5. Audit and Compliance Procedures
6. Security Operations Procedures

Secure Development Procedures

Pre-Development Security Review

Procedure SD-001: Security Requirements Analysis

Purpose: Ensure security requirements are identified before development begins.

Steps:

1. Review feature requirements for security implications
2. Identify cryptographic needs
3. Assess regulatory compliance requirements
4. Document security constraints
5. Get security team approval

Checklist:

• Threat model created/updated
• Cryptographic algorithms selected
• Key management requirements defined
• Compliance requirements identified
• Security tests planned

Secure Coding Procedures

Procedure SD-002: Cryptographic Implementation

Purpose: Ensure cryptographic code is implemented securely.

Steps:

1. Use only approved cryptographic libraries
2. Implement constant-time operations
3. Validate all inputs before processing
4. Handle errors without information leakage
5. Clear sensitive data after use

Code Example:

// Secure key derivation procedure
pub fn derive_key(
    master_key: &[u8; 32],
    context: &[u8],
    key_id: u64,
) -> Result<[u8; 32], KeyDerivationError> {
    // Step 1: Validate inputs
    if context.len() > 255 {
        return Err(KeyDerivationError::ContextTooLong);
    }
    
    // Step 2: Prepare derivation data
    let mut data = Vec::with_capacity(8 + 1 + context.len());
    data.extend_from_slice(&key_id.to_be_bytes());
    data.push(context.len() as u8);
    data.extend_from_slice(context);
    
    // Step 3: Derive key using HKDF
    let mut derived_key = [0u8; 32];
    hkdf_sha256(master_key, &data, b"metamui-key-derive", &mut derived_key)?;
    
    // Step 4: Clear intermediate data
    data.zeroize();
    
    Ok(derived_key)
}

Procedure SD-003: Memory Safety

Purpose: Prevent memory-related vulnerabilities.

Steps:

1. Avoid unsafe code blocks unless absolutely necessary
2. Document and review all unsafe code usage
3. Use bounds checking for all array accesses
4. Implement Drop trait for sensitive data
5. Use memory barriers to prevent optimization

Implementation:

use zeroize::{Zeroize, ZeroizeOnDrop};

#[derive(ZeroizeOnDrop)]
pub struct SecretKey {
    #[zeroize(skip)]
    algorithm: Algorithm,
    key_material: Vec<u8>,
}

impl Drop for SecretKey {
    fn drop(&mut self) {
        // Explicit zeroization with memory barrier
        self.key_material.zeroize();
        
        // Memory barrier to prevent reordering
        core::sync::atomic::fence(core::sync::atomic::Ordering::SeqCst);
    }
}

Code Review Procedures

Procedure SD-004: Security-Focused Code Review

Purpose: Identify security issues before code merger.

Review Checklist:

1. Input Validation
   • All external inputs validated
   • Buffer sizes checked
   • Integer overflow protection
2. Cryptography
   • Approved algorithms used
   • Proper key sizes
   • Secure random number generation
   • No hardcoded secrets
3. Memory Safety
   • No uninitialized memory use
   • Bounds checking present
   • Sensitive data cleared
4. Error Handling
   • No information leakage in errors
   • All errors handled
   • Fail-secure behavior

Key Management Procedures

Key Generation Procedures

Procedure KM-001: Master Key Generation

Purpose: Generate cryptographically secure master keys.

Steps:

1. Instantiate the HMAC_DRBG (DrbgRng::new() runs the power-up KATs and start-up health tests)
2. Reseed from the entropy source
3. Generate 256 bits of entropy
4. Apply key derivation function
5. Store in secure key storage
6. Log key generation event

Implementation:

pub fn generate_master_key() -> Result<MasterKey, KeyGenerationError> {
    // Step 1: Instantiate the DRBG (power-up KATs and start-up health tests run here)
    let mut rng = DrbgRng::new()?;
    
    // Step 2: Reseed from the entropy source
    rng.reseed()?;
    
    // Step 3: Generate entropy
    let mut entropy = [0u8; 32];
    rng.fill_bytes(&mut entropy)?;
    
    // Step 4: Derive master key
    let master_key = kdf_sha256(&entropy, b"metamui-master-key", 32)?;
    
    // Step 5: Clear entropy
    entropy.zeroize();
    
    // Step 6: Audit log
    audit_log(AuditEvent::MasterKeyGenerated {
        timestamp: SystemTime::now(),
        key_id: master_key.id(),
    })?;
    
    Ok(master_key)
}

Procedure KM-002: Key Rotation

Purpose: Rotate keys according to policy.

Steps:

1. Generate new key version
2. Re-encrypt data with new key
3. Verify re-encryption success
4. Update key version metadata
5. Schedule old key destruction
6. Audit log rotation

Key Rotation Schedule:

pub struct KeyRotationSchedule {
    key_type: KeyType,
    max_age: Duration,
    max_operations: u64,
}

const ROTATION_SCHEDULE: &[KeyRotationSchedule] = &[
    KeyRotationSchedule {
        key_type: KeyType::Master,
        max_age: Duration::from_secs(365 * 24 * 60 * 60), // 1 year
        max_operations: u64::MAX,
    },
    KeyRotationSchedule {
        key_type: KeyType::DataEncryption,
        max_age: Duration::from_secs(30 * 24 * 60 * 60), // 30 days
        max_operations: 1 << 32, // 2^32 operations
    },
];

Key Storage Procedures

Procedure KM-003: Secure Key Storage

Purpose: Store keys securely at rest.

Steps:

1. Encrypt key with Key Encryption Key (KEK)
2. Add integrity protection (HMAC)
3. Store in secure location
4. Set appropriate permissions
5. Enable audit logging

Storage Format:

#[derive(Serialize, Deserialize)]
pub struct StoredKey {
    version: u32,
    key_id: Uuid,
    algorithm: Algorithm,
    encrypted_key: Vec<u8>,
    nonce: [u8; 12],
    tag: [u8; 16],
    metadata: KeyMetadata,
    hmac: [u8; 32],
}

pub fn store_key(key: &SecretKey, kek: &[u8; 32]) -> Result<(), StorageError> {
    // Encrypt key material
    let (ciphertext, nonce, tag) = aes_256_gcm_encrypt(
        kek,
        &key.material,
        &key.metadata.to_bytes()?,
    )?;
    
    // Create storage structure
    let stored = StoredKey {
        version: 1,
        key_id: key.id,
        algorithm: key.algorithm,
        encrypted_key: ciphertext,
        nonce,
        tag,
        metadata: key.metadata.clone(),
        hmac: [0u8; 32],
    };
    
    // Compute HMAC over entire structure
    let hmac = hmac_sha256(kek, &stored.to_bytes()?);
    stored.hmac = hmac;
    
    // Store to secure location
    secure_storage::write(&key.id, &stored)?;
    
    Ok(())
}

Security Testing Procedures

Cryptographic Testing

Procedure ST-001: Algorithm Validation

Purpose: Verify cryptographic implementations against test vectors.

Steps:

1. Load official test vectors
2. Run algorithm with test inputs
3. Compare outputs
4. Verify timing consistency
5. Document results

Test Framework:

#[cfg(test)]
mod crypto_tests {
    use super::*;
    
    #[test]
    fn test_aes_256_gcm() {
        // NIST test vectors
        let test_vectors = load_nist_vectors("aes_gcm_256.json");
        
        for vector in test_vectors {
            let (ciphertext, tag) = aes_256_gcm_encrypt(
                &vector.key,
                &vector.nonce,
                &vector.plaintext,
                &vector.aad,
            ).expect("Encryption failed");
            
            assert_eq!(ciphertext, vector.expected_ciphertext);
            assert_eq!(tag, vector.expected_tag);
            
            // Verify constant time
            assert_constant_time(|| {
                aes_256_gcm_encrypt(&vector.key, &vector.nonce, &vector.plaintext, &vector.aad)
            });
        }
    }
}

Procedure ST-002: Side-Channel Testing

Purpose: Verify resistance to timing attacks.

Steps:

1. Instrument code for timing measurements
2. Run operations with different inputs
3. Statistical analysis of timings
4. Identify timing variations
5. Fix any variable-time operations

Testing Code:

pub fn test_constant_time_comparison() {
    let iterations = 100_000;
    let mut timings = Vec::with_capacity(iterations);
    
    for _ in 0..iterations {
        let a = random_bytes(32);
        let b = random_bytes(32);
        
        let start = precise_time_ns();
        let _ = constant_time_eq(&a, &b);
        let end = precise_time_ns();
        
        timings.push(end - start);
    }
    
    // Statistical analysis
    let mean = statistical::mean(&timings);
    let std_dev = statistical::std_dev(&timings);
    let max_deviation = statistical::max_deviation(&timings);
    
    // Assert timing is consistent
    assert!(std_dev < mean * 0.05); // Less than 5% variation
    assert!(max_deviation < mean * 0.10); // Max 10% deviation
}

Penetration Testing

Procedure ST-003: Security Penetration Testing

Purpose: Identify vulnerabilities through active testing.

Test Categories:

1. Input Validation
   • Fuzzing with AFL++
   • Boundary value testing
   • Injection attacks
2. Memory Safety
   • Address sanitizer
   • Memory sanitizer
   • Undefined behavior sanitizer
3. Cryptographic Attacks
   • Nonce reuse detection
   • Weak randomness testing
   • Protocol downgrade attempts

Fuzzing Configuration:

#!/bin/bash
# Fuzz testing script

# Build with fuzzing instrumentation
cargo fuzz build

# Run fuzzer for each target
for target in $(cargo fuzz list); do
    echo "Fuzzing $target..."
    cargo fuzz run $target -- \
        -max_len=65536 \
        -timeout=30 \
        -max_total_time=3600 \
        -print_final_stats=1
done

# Analyze crashes
for crash in fuzz/artifacts/*/crash-*; do
    echo "Analyzing crash: $crash"
    cargo fuzz reproduce $target $crash
done

Incident Response Procedures

Incident Detection

Procedure IR-001: Security Incident Detection

Purpose: Quickly identify and classify security incidents.

Detection Sources:

1. Automated monitoring alerts
2. User reports
3. Security audit logs
4. Vulnerability scanners
5. Third-party notifications

Initial Response:

pub async fn handle_security_alert(alert: SecurityAlert) -> Result<(), IncidentError> {
    // Step 1: Log incident
    let incident_id = log_incident(&alert)?;
    
    // Step 2: Assess severity
    let severity = assess_severity(&alert)?;
    
    // Step 3: Notify team
    match severity {
        Severity::Critical => {
            notify_oncall_immediately(&alert).await?;
            page_security_team(&alert).await?;
        }
        Severity::High => {
            notify_security_team(&alert).await?;
        }
        Severity::Medium | Severity::Low => {
            create_security_ticket(&alert).await?;
        }
    }
    
    // Step 4: Begin containment
    if severity >= Severity::High {
        begin_containment(&alert).await?;
    }
    
    Ok(())
}

Incident Containment

Procedure IR-002: Incident Containment

Purpose: Limit damage from security incidents.

Containment Actions:

1. Key Compromise

   pub async fn contain_key_compromise(key_id: KeyId) -> Result<(), ContainmentError> {
       // Revoke key immediately
       key_manager::revoke_key(key_id).await?;
          
       // Identify affected systems
       let affected = identify_key_usage(key_id).await?;
          
       // Rotate to new key
       let new_key = key_manager::emergency_rotation(key_id).await?;
          
       // Update affected systems
       for system in affected {
           system.update_key(key_id, new_key).await?;
       }
          
       Ok(())
   }
   

2. Data Breach

   pub async fn contain_data_breach(breach: DataBreach) -> Result<(), ContainmentError> {
       // Isolate affected systems
       for system in &breach.affected_systems {
           network::isolate(system).await?;
       }
          
       // Revoke access tokens
       for token in identify_active_tokens(&breach).await? {
           auth::revoke_token(token).await?;
       }
          
       // Enable enhanced monitoring
       monitoring::enable_enhanced_mode(&breach.affected_systems).await?;
          
       Ok(())
   }
   

Audit and Compliance Procedures

Security Auditing

Procedure AC-001: Security Audit Logging

Purpose: Maintain comprehensive security audit trail.

Audit Events:

#[derive(Serialize, Deserialize)]
pub enum AuditEvent {
    // Key management
    KeyGenerated { key_id: KeyId, algorithm: Algorithm },
    KeyRotated { old_id: KeyId, new_id: KeyId },
    KeyDestroyed { key_id: KeyId },
    
    // Authentication
    LoginAttempt { user: UserId, success: bool },
    TokenIssued { user: UserId, token_id: TokenId },
    TokenRevoked { token_id: TokenId, reason: String },
    
    // Data access
    DataEncrypted { data_id: DataId, key_id: KeyId },
    DataDecrypted { data_id: DataId, key_id: KeyId },
    
    // Configuration
    ConfigChanged { setting: String, old_value: String, new_value: String },
    
    // Security events
    SecurityAlert { alert_type: AlertType, severity: Severity },
    IncidentCreated { incident_id: IncidentId },
}

pub fn audit_log(event: AuditEvent) -> Result<(), AuditError> {
    let entry = AuditEntry {
        timestamp: SystemTime::now(),
        event,
        actor: current_actor()?,
        session_id: current_session()?,
        correlation_id: Uuid::new_v4(),
    };
    
    // Sign entry for integrity
    let signature = sign_audit_entry(&entry)?;
    
    // Store in append-only log
    audit_store::append(entry, signature)?;
    
    Ok(())
}

Compliance Verification

Procedure AC-002: DRBG health-test review

Purpose: Confirm the HMAC_DRBG (SP 800-90A) and its SP 800-90B-style health tests stay as documented. The project holds no FIPS 140-3 validation.

Verification Steps:

1. Algorithm Compliance

   pub fn verify_fips_algorithms() -> Result<(), ComplianceError> {
       // Check only approved algorithms used
       for algorithm in inventory::list_algorithms()? {
           if !FIPS_APPROVED_ALGORITHMS.contains(&algorithm) {
               return Err(ComplianceError::NonApprovedAlgorithm(algorithm));
           }
       }
          
       // Verify algorithm parameters
       verify_key_sizes()?;
       verify_mode_compliance()?;
          
       Ok(())
   }
   

2. Self-Test Compliance

   pub fn run_fips_self_tests() -> Result<(), SelfTestError> {
       // Power-on self-tests
       crypto_self_test()?;
       integrity_self_test()?;
          
       // Conditional self-tests
       if new_key_generated() {
           key_generation_self_test()?;
       }
          
       if firmware_updated() {
           firmware_integrity_test()?;
       }
          
       Ok(())
   }
   

Security Operations Procedures

Monitoring Procedures

Procedure SO-001: Continuous Security Monitoring

Purpose: Detect security issues in real-time.

Monitoring Dashboard:

pub struct SecurityMetrics {
    // Cryptographic operations
    pub encryption_ops_per_sec: f64,
    pub decryption_ops_per_sec: f64,
    pub key_generation_rate: f64,
    
    // Security events
    pub failed_auth_attempts: u64,
    pub anomaly_detections: u64,
    pub policy_violations: u64,
    
    // System health
    pub entropy_pool_level: f64,
    pub key_rotation_lag: Duration,
    pub audit_log_integrity: bool,
}

pub async fn monitor_security() -> Result<(), MonitoringError> {
    loop {
        let metrics = collect_security_metrics().await?;
        
        // Check thresholds
        if metrics.failed_auth_attempts > 100 {
            alert(AlertType::BruteForceAttempt).await?;
        }
        
        if metrics.entropy_pool_level < 0.5 {
            alert(AlertType::LowEntropy).await?;
        }
        
        if !metrics.audit_log_integrity {
            alert(AlertType::AuditTamper).await?;
        }
        
        // Update dashboard
        dashboard::update(metrics).await?;
        
        tokio::time::sleep(Duration::from_secs(60)).await;
    }
}

Backup and Recovery

Procedure SO-002: Secure Backup Procedures

Purpose: Enable recovery while maintaining security.

Backup Process:

pub async fn backup_security_data() -> Result<BackupId, BackupError> {
    // Step 1: Create backup encryption key
    let backup_key = generate_backup_key()?;
    
    // Step 2: Collect security-critical data
    let backup_data = BackupData {
        master_keys: export_master_keys()?,
        key_metadata: export_key_metadata()?,
        audit_logs: export_audit_logs()?,
        configuration: export_security_config()?,
    };
    
    // Step 3: Encrypt backup
    let encrypted = encrypt_backup(&backup_data, &backup_key)?;
    
    // Step 4: Split key using Shamir's Secret Sharing
    let key_shares = shamir::split_secret(&backup_key, 5, 3)?; // 5 shares, 3 to recover
    
    // Step 5: Store encrypted backup
    let backup_id = secure_storage::store_backup(encrypted).await?;
    
    // Step 6: Distribute key shares
    for (i, share) in key_shares.iter().enumerate() {
        key_custodian::store_share(i, share).await?;
    }
    
    Ok(backup_id)
}

Performance Optimization

Procedure SO-003: Security Performance Tuning

Purpose: Optimize security operations without compromising protection.

Optimization Strategies:

1. Caching

   pub struct SecurityCache {
       // Cache validated tokens
       token_cache: LruCache<TokenId, TokenInfo>,
          
       // Cache key derivations
       derived_keys: LruCache<(KeyId, Context), DerivedKey>,
          
       // Cache permission checks
       permissions: LruCache<(UserId, Resource), Permission>,
   }
   

2. Batch Operations

   pub async fn batch_encrypt(items: Vec<Data>) -> Result<Vec<EncryptedData>, CryptoError> {
       // Process in parallel batches
       let batch_size = 1000;
       let mut results = Vec::with_capacity(items.len());
          
       for chunk in items.chunks(batch_size) {
           let batch_results: Vec<_> = chunk
               .par_iter()
               .map(|item| encrypt(item))
               .collect::<Result<Vec<_>, _>>()?;
                  
           results.extend(batch_results);
       }
          
       Ok(results)
   }
   

Appendices

Appendix A: Security Contacts

Role	Contact	Availability
Security Lead	security@metamui.id	24/7
Incident Response	incident@metamui.id	24/7
Compliance Officer	compliance@metamui.id	Business hours
External Auditor	auditor@security-firm.com	Scheduled

Appendix B: Tool References

Tool	Purpose	Documentation
cargo-fuzz	Fuzzing	Link
cargo-audit	Dependency scanning	Link
MIRI	Undefined behavior detection	Link

Appendix C: Compliance Matrices

Requirement	FIPS 140-3 (informative; not validated)	Common Criteria	Implementation
Crypto Algorithms	Approved only	Validated	✓ Implemented
Key Management	Secure lifecycle	Formal model	✓ Implemented
Audit Logging	Required	Required	✓ Implemented
Self-Tests	Mandatory	Recommended	✓ Implemented

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Document Version: 1.0 Last Updated: January 2025 Next Review: April 2025