whspbrd-final/typio/yum/yum.go
2026-05-02 22:09:19 +02:00

115 lines
2.2 KiB
Go

package yum
// 95% of AI generated code
// human designed & reviewed
import (
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"errors"
"io"
"os"
"golang.org/x/crypto/argon2"
)
const (
saltSize = 16
keySize = 32
nonceSize = 12
// Argon2 params (tune if needed)
argonTime = 1
argonMemory = 64 * 1024 // 64 MB
argonThreads = 4
)
// YumSave encrypts and saves data securely to disk.
func YumSave(path string, data []byte, password []byte) error {
// Generate salt
salt := make([]byte, saltSize)
if _, err := rand.Read(salt); err != nil {
return err
}
// Derive key
key := argon2.IDKey(password, salt, argonTime, argonMemory, argonThreads, keySize)
// Create AES cipher
block, err := aes.NewCipher(key)
if err != nil {
return err
}
gcm, err := cipher.NewGCM(block)
if err != nil {
return err
}
// Generate nonce
nonce := make([]byte, nonceSize)
if _, err := rand.Read(nonce); err != nil {
return err
}
// Encrypt
ciphertext := gcm.Seal(nil, nonce, data, nil)
// File format: [salt | nonce | ciphertext]
fileData := append(salt, nonce...)
fileData = append(fileData, ciphertext...)
return os.WriteFile(path, fileData, 0600)
}
// YumLoad loads and decrypts data from disk.
func YumLoad(path string, password []byte) ([]byte, error) {
fileData, err := os.ReadFile(path)
if err != nil {
return nil, err
}
if len(fileData) < saltSize+nonceSize {
return nil, errors.New("file too short")
}
// Extract components
salt := fileData[:saltSize]
nonce := fileData[saltSize : saltSize+nonceSize]
ciphertext := fileData[saltSize+nonceSize:]
// Derive key
key := argon2.IDKey(password, salt, argonTime, argonMemory, argonThreads, keySize)
// Recreate cipher
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
gcm, err := cipher.NewGCM(block)
if err != nil {
return nil, err
}
// Decrypt
plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
if err != nil {
return nil, errors.New("decryption failed (wrong password or corrupted data)")
}
return plaintext, nil
}
func YumSeed(buf []byte) error {
_, err := io.ReadFull(rand.Reader, buf)
if err != nil {
for i := range buf {
buf[i] = 0
}
return err
}
return nil
}