87 lines
2.0 KiB
Go
87 lines
2.0 KiB
Go
package crypto
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import (
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"crypto/rand"
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"crypto/rsa"
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"crypto/x509"
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"encoding/pem"
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"errors"
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"fmt"
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)
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func NewKeyRSA(bitSize int) (pubPEM []byte, keyPEM []byte, err error) {
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// 生成 RSA 密鑰對
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key, err := rsa.GenerateKey(rand.Reader, bitSize)
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if err != nil {
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return nil, nil, fmt.Errorf("failed to generate RSA key: %w", err)
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}
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// 提取公鑰部分並轉換為 PEM 格式
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pubBytes, err := x509.MarshalPKIXPublicKey(key.Public())
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if err != nil {
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return nil, nil, fmt.Errorf("failed to marshal public key: %w", err)
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}
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pubPEM = pem.EncodeToMemory(
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&pem.Block{
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Type: "RSA PUBLIC KEY",
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Bytes: pubBytes,
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},
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)
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// 編碼私鑰為 PKCS#1 ASN.1 PEM 格式
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keyPEM = pem.EncodeToMemory(
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&pem.Block{
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Type: "RSA PRIVATE KEY",
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Bytes: x509.MarshalPKCS1PrivateKey(key),
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},
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)
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return pubPEM, keyPEM, nil
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}
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// EncryptRSA rsa加密
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func EncryptRSA(value, publicKey []byte) ([]byte, error) {
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block, _ := pem.Decode(publicKey)
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if block == nil {
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return nil, errors.New("failed to decode public key PEM")
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}
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pubInterface, err := x509.ParsePKIXPublicKey(block.Bytes)
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if err != nil {
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return nil, fmt.Errorf("failed to parse public key: %w", err)
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}
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pub, ok := pubInterface.(*rsa.PublicKey)
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if !ok {
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return nil, errors.New("invalid public key type")
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}
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// 使用公鑰進行加密
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enc, err := rsa.EncryptPKCS1v15(rand.Reader, pub, value)
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if err != nil {
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return nil, fmt.Errorf("failed to encrypt with RSA: %w", err)
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}
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return enc, nil
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}
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// DecryptRSA rsa解密
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func DecryptRSA(ciphertext, privateKey []byte) ([]byte, error) {
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block, _ := pem.Decode(privateKey)
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if block == nil {
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return nil, errors.New("failed to decode private key PEM")
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}
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priv, err := x509.ParsePKCS1PrivateKey(block.Bytes)
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if err != nil {
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return nil, fmt.Errorf("failed to parse private key: %w", err)
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}
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dec, err := rsa.DecryptPKCS1v15(rand.Reader, priv, ciphertext)
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if err != nil {
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return nil, fmt.Errorf("failed to decrypt with RSA: %w", err)
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}
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return dec, nil
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}
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