feat(crypto):完成RSA加密算法功能。

2023-07-15 08:11:07 +08:00
parent b004e952c4
commit 5e284f320d
4 changed files with 395 additions and 5 deletions
--- a/encryption/rsa/key.go
+++ b/encryption/rsa/key.go
@@ -0,0 +1,141 @@
+package rsa
+
+import (
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+)
+
+type KeyFormat int
+
+const (
+	RSA KeyFormat = iota
+	COMMON
+)
+
+// 将指定的私钥编码为PEM格式，如果不指定具体格式将使用RSA PRIVATE KEY(PKCS1)格式。
+func EncodePrivateKey(key *rsa.PrivateKey, format ...KeyFormat) ([]byte, error) {
+	var block *pem.Block
+	switch append(format, RSA)[0] {
+	case COMMON:
+		key, err := x509.MarshalPKCS8PrivateKey(key)
+		if err != nil {
+			return nil, fmt.Errorf("不支持的私钥格式，%w", err)
+		}
+		block = &pem.Block{
+			Type:  "PRIVATE KEY",
+			Bytes: key,
+		}
+	case RSA:
+		fallthrough
+	default:
+		key := x509.MarshalPKCS1PrivateKey(key)
+		block = &pem.Block{
+			Type:  "RSA PRIVATE KEY",
+			Bytes: key,
+		}
+	}
+	return pem.EncodeToMemory(block), nil
+}
+
+// 将指定的公钥编码为PEM格式，如果不指定具体格式将使用RSA PUBLIC KEY(PKCS1)格式。
+func EncodePublicKey(key *rsa.PublicKey, format ...KeyFormat) ([]byte, error) {
+	var block *pem.Block
+	switch append(format, RSA)[0] {
+	case COMMON:
+		key, err := x509.MarshalPKIXPublicKey(key)
+		if err != nil {
+			return nil, fmt.Errorf("不支持的公钥格式，%w", err)
+		}
+		block = &pem.Block{
+			Type:  "PUBLIC KEY",
+			Bytes: key,
+		}
+	case RSA:
+		fallthrough
+	default:
+		key := x509.MarshalPKCS1PublicKey(key)
+		block = &pem.Block{
+			Type:  "RSA PUBLIC KEY",
+			Bytes: key,
+		}
+	}
+	return pem.EncodeToMemory(block), nil
+}
+
+// 将给定的PEM证书内容解析为RSA私钥。
+// 仅能读取PEM证书中的第一个私钥编码段。
+func DecodePrivateKey(cert []byte) (*rsa.PrivateKey, error) {
+	var (
+		block          *pem.Block
+		pemRestContent = cert
+	)
+	for {
+		block, pemRestContent = pem.Decode(pemRestContent)
+		if block == nil {
+			return nil, &KeyNotFoundError{}
+		}
+		if block.Type == "PRIVATE KEY" || block.Type == "RSA PRIVATE KEY" {
+			break
+		}
+	}
+	switch block.Type {
+	case "PRIVATE KEY":
+		key, err := x509.ParsePKCS8PrivateKey(block.Bytes)
+		if err != nil {
+			return nil, fmt.Errorf("不支持的私钥格式，%w", err)
+		}
+		pKey, ok := key.(*rsa.PrivateKey)
+		if !ok {
+			return nil, fmt.Errorf("提供的私钥不是RSA专用私钥，%w", err)
+		}
+		return pKey, nil
+	case "RSA PRIVATE KEY":
+		key, err := x509.ParsePKCS1PrivateKey(block.Bytes)
+		if err != nil {
+			return nil, fmt.Errorf("不支持的私钥格式，%w", err)
+		}
+		return key, nil
+	default:
+		return nil, fmt.Errorf("不支持的私钥格式或者私钥不存在，%s", block.Type)
+	}
+}
+
+// 将给定的PEM证书内容解析为RSA公钥。
+// 仅能读取PEM证书中的第一个公钥编码段。
+func DecodePublicKey(cert []byte) (*rsa.PublicKey, error) {
+	var (
+		block          *pem.Block
+		pemRestContent = cert
+	)
+	for {
+		block, pemRestContent = pem.Decode(pemRestContent)
+		if block == nil {
+			return nil, &KeyNotFoundError{}
+		}
+		if block.Type == "PUBLIC KEY" || block.Type == "RSA PUBLIC KEY" {
+			break
+		}
+	}
+	switch block.Type {
+	case "PUBLIC KEY":
+		key, err := x509.ParsePKIXPublicKey(block.Bytes)
+		if err != nil {
+			return nil, fmt.Errorf("不支持的公钥格式，%w", err)
+		}
+		pKey, ok := key.(*rsa.PublicKey)
+		if !ok {
+			return nil, fmt.Errorf("提供的公钥不是RSA专用公钥，%w", err)
+		}
+		return pKey, nil
+	case "RSA PUBLIC KEY":
+		key, err := x509.ParsePKCS1PublicKey(block.Bytes)
+		if err != nil {
+			return nil, fmt.Errorf("不支持的公钥格式，%w", err)
+		}
+		return key, nil
+	default:
+		return nil, fmt.Errorf("不支持的公钥格式或者公钥不存在，%s", block.Type)
+	}
+}