The first step of the #加密项目 encryption project is to clarify the core objectives and application scenarios, as different scenarios have vastly different encryption requirements. Common scenarios include:

Data Storage Encryption: Protecting static data (such as user privacy, financial data) in databases, file systems, and cloud storage.

Data Transmission Encryption: Protecting dynamic data (such as HTTPS, instant messaging, IoT device communication) in network communications.

Identity Authentication and Signing: Verifying user/device identity (such as digital signatures, JWT tokens) or preventing data tampering (such as blockchain transactions).

Compliance Requirements: Meeting mandatory data encryption requirements of regulations such as GDPR, HIPAA, and the Personal Information Protection Law.

Common Risks and Responses

Key Leakage:

Risk: Keys being stolen (e.g., code repository leakage, server intrusion).

Response: Use HSM/KMS to manage keys, restrict key access permissions (principle of least privilege), and rotate keys regularly.

Outdated Algorithms:

Risk: Using algorithms that have been cracked (e.g., DES, MD5, SHA-1).

Response: Follow algorithm recommendations from authoritative organizations such as NIST and the State Cryptography Administration, and upgrade in a timely manner (e.g., replacing SHA-1 with SHA-256).

Side-Channel Attacks:

Risk: Key information being leaked through power consumption, timing, electromagnetic radiation, etc.

Response: Use algorithms resistant to side-channel attacks (e.g., constant time algorithms), and reinforce at the hardware level (e.g., secure chips).

Data Tampering:

Risk: Ciphertext being tampered with but undetectable (e.g., not using authenticated encryption modes).

Response: Prefer AEAD modes (e.g., GCM), or add HMAC verification additionally.