# HIPAA Readiness Assessment

This document maps the pymedsec package features to HIPAA requirements under 45 CFR 164.312 (Technical Safeguards).

## Executive Summary

The pymedsec package provides technical safeguards that align with HIPAA requirements for protecting electronic protected health information (ePHI). This assessment demonstrates readiness for HIPAA compliance when properly configured and deployed.

## HIPAA Technical Safeguards Mapping

### 164.312(a)(1) - Access Control

**Requirement**: Assign a unique name and/or number for identifying and tracking user identity and establish procedures for obtaining necessary electronic protected health information during an emergency.

**Implementation**:

- **User Authentication**: Environment variable `IMGSEC_ACTOR` tracks the user performing operations
- **Audit Logging**: All operations are logged with actor identification
- **Emergency Access**: Mock KMS backend allows emergency access when primary KMS is unavailable
- **Role-Based Access**: KMS key policies control access to encrypted data

**Evidence**:

```python
# Actor tracking in audit logs
audit.log_operation(
    operation='decrypt_data',
    actor=config.get_config().actor,
    outcome='success'
)
```

### 164.312(a)(2)(i) - Automatic Logoff

**Requirement**: Implement electronic procedures that terminate an electronic session after a predetermined time of inactivity.

**Implementation**:

- **Session Management**: No persistent sessions maintained
- **Memory Cleanup**: Sensitive data is zeroized after use
- **Resource Cleanup**: Context managers ensure proper cleanup

**Evidence**:

```python
# Automatic memory cleanup
plaintext_data = b'\x00' * len(plaintext_data)
del plaintext_data
```

### 164.312(a)(2)(ii) - Encryption and Decryption

**Requirement**: Implement a mechanism to encrypt and decrypt electronic protected health information.

**Implementation**:

- **Strong Encryption**: AES-256-GCM with 96-bit nonces
- **Key Management**: KMS-based envelope encryption
- **Key Rotation**: Configurable key rotation policies
- **Algorithm Agility**: Pluggable KMS backends

**Evidence**:

```python
# AES-256-GCM encryption
aesgcm = AESGCM(data_key)
ciphertext = aesgcm.encrypt(nonce, plaintext_data, aad_bytes)
```

### 164.312(b) - Audit Controls

**Requirement**: Implement hardware, software, and/or procedural mechanisms that record and examine activity in information systems that contain or use electronic protected health information.

**Implementation**:

- **Comprehensive Logging**: All operations logged with JSONL format
- **Tamper Evidence**: HMAC signatures on all log entries
- **Integrity Verification**: Rolling anchor hashes every 1000 lines
- **Non-Repudiation**: Cryptographic audit trail

**Evidence**:

```python
# HMAC-signed audit entries
signature = hmac.new(
    self.audit_secret,
    entry_json.encode('utf-8'),
    hashlib.sha256
).hexdigest()
```

### 164.312(c)(1) - Integrity

**Requirement**: Implement electronic mechanisms to corroborate that electronic protected health information has not been improperly altered or destroyed.

**Implementation**:

- **Cryptographic Integrity**: AES-GCM provides authenticated encryption
- **Hash Verification**: SHA-256 hashes for data integrity
- **Package Verification**: Comprehensive integrity checks
- **Tamper Detection**: Failed decryption indicates tampering

**Evidence**:

```python
# Integrity verification
def verify_package_integrity(encrypted_package):
    # Comprehensive integrity checks including:
    # - Schema validation
    # - AAD validation
    # - Base64 validation
    # - KMS accessibility
```

### 164.312(c)(2) - Mechanism to Authenticate ePHI

**Requirement**: Implement electronic mechanisms to corroborate that electronic protected health information has not been improperly altered or destroyed in a manner that is addressable.

**Implementation**:

- **Digital Signatures**: HMAC-SHA256 for data authentication
- **Policy Hashing**: SHA-256 hash of active policy in AAD
- **Nonce Uniqueness**: Cryptographic nonce tracking
- **AAD Verification**: Additional authenticated data validation

**Evidence**:

```python
# Policy hash in AAD for authentication
aad = {
    "policy_hash": cfg.policy_hash,
    "dataset_id": dataset_id,
    "pixel_hash": pixel_hash,
    # ... other AAD fields
}
```

### 164.312(d) - Person or Entity Authentication

**Requirement**: Implement procedures to verify that a person or entity seeking access to electronic protected health information is the one claimed.

**Implementation**:

- **KMS Authentication**: AWS IAM or Vault authentication
- **Actor Identification**: Environment-based user identification
- **Audit Trail**: All access attempts logged
- **Multi-Factor Support**: Supported through KMS backends

**Evidence**:

```python
# KMS-based authentication
def verify_key_access(self, key_ref):
    response = self.client.describe_key(KeyId=key_ref)
    # Validates authenticated access to KMS key
```

### 164.312(e)(1) - Transmission Security

**Requirement**: Implement technical security measures to guard against unauthorized access to electronic protected health information that is being transmitted over an electronic communications network.

**Implementation**:

- **Encryption in Transit**: Data encrypted before transmission
- **End-to-End Security**: Only encrypted packages transmitted
- **Key Protection**: KMS keys never transmitted in plaintext
- **Network Security**: Compatible with TLS/VPN transport security

**Evidence**:

```python
# Only encrypted data transmitted
encrypted_package = crypto.encrypt_data(plaintext_data, ...)
# plaintext_data is zeroized before any network operations
```

### 164.312(e)(2)(ii) - Encryption

**Requirement**: Implement a mechanism to encrypt electronic protected health information whenever deemed appropriate.

**Implementation**:

- **Default Encryption**: All data encrypted by default
- **Strong Algorithms**: AES-256-GCM with NIST-approved parameters
- **Key Hierarchy**: Master keys in KMS, data keys per object
- **Forward Secrecy**: Unique keys per encryption operation

## Implementation Guidelines

### Required Configuration

1. **Policy Configuration**: Set `IMGSEC_POLICY` to compliant policy file
2. **KMS Backend**: Configure production KMS (AWS KMS or Vault)
3. **Audit Logging**: Enable comprehensive audit logging
4. **Actor Identification**: Set `IMGSEC_ACTOR` appropriately

### Deployment Checklist

- [ ] Production KMS configured and accessible
- [ ] Audit logs configured with appropriate retention
- [ ] Policy file reviewed and approved
- [ ] Access controls implemented at infrastructure level
- [ ] Backup and disaster recovery procedures established
- [ ] Staff training completed on emergency procedures

### Risk Assessment

| Risk Category  | Mitigation                                           |
| -------------- | ---------------------------------------------------- |
| Key Compromise | Key rotation, HSM storage, access logging            |
| Data Breach    | Strong encryption, access controls, audit logging    |
| System Failure | Backup procedures, redundant systems                 |
| Insider Threat | Audit logging, separation of duties, access controls |

## Compliance Verification

### Technical Tests

1. **Encryption Verification**: Verify AES-256-GCM implementation
2. **Key Management**: Test KMS integration and key rotation
3. **Audit Integrity**: Verify HMAC signatures and anchor hashes
4. **Access Controls**: Test authentication and authorization

### Documentation Requirements

1. **Security Architecture**: Document system design and controls
2. **Risk Assessment**: Conduct and document risk analysis
3. **Policies and Procedures**: Establish operational procedures
4. **Training Records**: Document staff training and competency

## Limitations and Disclaimers

1. **Not a BAA**: This software does not constitute a Business Associate Agreement
2. **Infrastructure Required**: Requires properly configured supporting infrastructure
3. **Operational Controls**: Technical controls must be supplemented with administrative controls
4. **Ongoing Compliance**: Requires ongoing monitoring and maintenance

## Contact Information

For HIPAA compliance questions or security reviews, use:

- Security reports (private): https://github.com/Faerque/pymedsec/security/advisories/new
- General questions: https://github.com/Faerque/pymedsec/discussions

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**Disclaimer**: This assessment demonstrates technical readiness for HIPAA compliance. Actual compliance requires proper configuration, supporting infrastructure, administrative controls, and ongoing monitoring. Consult with qualified compliance professionals for complete HIPAA compliance assessment.
