# Proposal: Add PQC-Based Secure Voting MVP

## Summary
Implement Minimum Viable Product for secure electronic voting using Post-Quantum Cryptography (Paillier + Kyber + Dilithium) and Blockchain for vote recording.

## Change ID
`add-pqc-voting-mvp`

## Motivation
- Enable secure electronic voting with vote secrecy and integrity
- Implement homomorphic encryption for private vote counting
- Use post-quantum cryptography (Kyber, Dilithium) for quantum resistance
- Provide blockchain-based immutable vote records
- Support individual and universal verifiability

## Scope
This proposal adds the complete voting system with:
1. Cryptographic toolkit (Paillier, Kyber, Dilithium, ZKP)
2. Blockchain module for vote recording
3. Voting API endpoints for ballot submission
4. Frontend voting interface with client-side encryption
5. Blockchain visualization and verification
6. Vote counting with homomorphic properties
7. Results display and audit reporting

## Affected Capabilities

### New Capabilities
- `voting-encryption`: Homomorphic vote encryption
- `blockchain-votes`: Immutable vote recording
- `pqc-signatures`: Post-quantum ballot and block signing
- `vote-submission`: Secure ballot submission workflow
- `vote-counting`: Homomorphic vote summation
- `blockchain-verification`: Chain integrity verification

### Modified Capabilities
- `authentication`: Extend with voter Dilithium key generation
- `api-structure`: Add new voting endpoints

## Key Design Decisions

1. **Vote Encryption**: Paillier homomorphic encryption allows voting without decrypting individual votes
2. **Post-Quantum**: Kyber protects Paillier key, Dilithium signs ballots and blocks
3. **Blockchain**: SHA-256 hash chain ensures vote immutability
4. **Anonymity**: Transaction IDs instead of voter IDs in blockchain
5. **Verifiability**: ZKP proves ballot validity, chain verification proves counting accuracy

## Implementation Phases

1. **Phase 1**: Cryptographic foundations (crypto_tools.py + blockchain.py)
2. **Phase 2**: Backend API endpoints
3. **Phase 3**: Frontend voting interface
4. **Phase 4**: Blockchain visualization
5. **Phase 5**: Results and reporting
6. **Phase 6**: Technical report and testing

## Success Criteria

- [ ] All cryptographic operations implemented and tested
- [ ] Blockchain structure immutable and verifiable
- [ ] Voting API endpoints functional
- [ ] Frontend enables secure ballot encryption and submission
- [ ] Vote counting produces verifiable results
- [ ] Complete technical & scientific report
- [ ] Docker deployment successful
- [ ] Security properties validated

## Related Issues/Discussions
- Course project: Cryptographie Industrielle Avancée (CIA)
- Requirement: Secure e-voting system with PQC and blockchain