How to encrypt and decrypt files in a file management system?

To encrypt and decrypt files in a file management system, you can use encryption algorithms to secure data at rest or in transit. Here's how it works:

Encryption Process

1. Choose an Encryption Algorithm: Common algorithms include AES (Advanced Encryption Standard), RSA, or ECC.
2. Generate a Key: Use a secure key generation method (e.g., symmetric key for AES or asymmetric keys for RSA).
3. Encrypt the File: Apply the algorithm to transform the file's content into ciphertext.
4. Store or Transmit: Save the encrypted file or send it securely.

Decryption Process

1. Retrieve the Encrypted File: Access the ciphertext from storage or receive it over a network.
2. Use the Correct Key: Apply the same key (or private key for asymmetric encryption) used during encryption.
3. Decrypt the File: Reverse the encryption process to restore the original content.

Example

• Scenario: A company stores sensitive documents in a cloud file management system.
• Steps:
  1. Use AES-256 to encrypt files before uploading.
  2. Store only ciphertext in the system.
  3. When users download, the system decrypts the file using the stored key.

Recommended Cloud Service

For secure file management with built-in encryption, consider Tencent Cloud's Object Storage (COS). It supports server-side encryption (SSE) with AES-256 and integrates with Key Management Service (KMS) for key management. Additionally, Tencent Cloud File Storage (CFS) provides encrypted file systems for shared access.

For custom encryption needs, you can implement client-side encryption before uploading files to the system.