Initial commit

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

common/crypt/rsa.go

@@ -0,0 +1,140 @@
+package crypt
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+
+	"91porn-server/common/log"
+)
+
+func splitBytesSlice(data []byte, n int) [][]byte {
+	var chunk []byte
+	chunks := make([][]byte, 0, len(data)/n+1)
+	for len(data) >= n {
+		chunk, data = data[:n], data[n:]
+		chunks = append(chunks, chunk)
+	}
+	if len(data) > 0 {
+		chunks = append(chunks, data[:])
+	}
+	return chunks
+}
+
+func rsaBytesToPublicKey(pub []byte) (*rsa.PublicKey, error) {
+	block, _ := pem.Decode(pub)
+	b := block.Bytes
+	var err error
+	pk, err := x509.ParsePKIXPublicKey(b)
+	if err != nil {
+		log.Error("RSABytesToPublicKey ParsePKIXPublicKey err", log.E(err))
+		return nil, err
+	}
+	if pk_, ok := pk.(*rsa.PublicKey); ok {
+		return pk_, nil
+	}
+	log.Error("RSABytesToPublicKey error input not PublicKey")
+	return nil, errors.New("Not RSA PublicKey format")
+}
+
+func rsaBytesToPrivateKey(priv []byte) (*rsa.PrivateKey, error) {
+	block, _ := pem.Decode(priv)
+	b := block.Bytes
+	var err error
+	key, err := x509.ParsePKCS8PrivateKey(b)
+	if err != nil {
+		log.Error("RSABytesToPrivateKey ParsePKCS8PrivateKey err", log.E(err))
+		return nil, err
+	}
+	if pk_, ok := key.(*rsa.PrivateKey); ok {
+		return pk_, nil
+	}
+	log.Error("RSABytesToPrivateKey error input not PrivateKey")
+	return nil, errors.New("Not RSA PrivateKey format")
+}
+
+// 公钥加密
+func RSAEncryptByPublicKey(pemPubKey string, data []byte) ([]byte, error) {
+	pubKey, err := rsaBytesToPublicKey([]byte(pemPubKey))
+	if err != nil {
+		log.Error("RSAEncryptByPublicKey rsaBytesToPublicKey err", log.E(err))
+		return nil, err
+	}
+	partLen := pubKey.N.BitLen()/8 - 11
+	chunks := splitBytesSlice(data, partLen)
+	result := bytes.Buffer{}
+	for _, chunk := range chunks {
+		cipherSilce, err := rsa.EncryptPKCS1v15(rand.Reader, pubKey, chunk)
+		if err != nil {
+			log.Error("RSAEncryptByPublicKey EncryptPKCS1v15 err", log.E(err))
+			return nil, err
+		}
+		result.Write(cipherSilce)
+	}
+	return result.Bytes(), nil
+}
+
+// 私玥签名
+func RSASignByPrivateKey(pemPrivateKey string, data []byte, hash crypto.Hash) ([]byte, error) {
+	privateKey, err := rsaBytesToPrivateKey([]byte(pemPrivateKey))
+	if err != nil {
+		log.Error("RSASignByPrivateKey rsaBytesToPrivateKey err", log.E(err))
+		return nil, err
+	}
+	h := hash.New()
+	h.Write(data)
+	hashed := make([]byte, 0)
+	hashed = h.Sum(hashed)
+	return rsa.SignPKCS1v15(rand.Reader, privateKey, hash, hashed)
+}
+
+func RSAVerifyByPublicKey(publicKey string, data, sign []byte, hash crypto.Hash) (err error) {
+	pubKey, err := rsaBytesToPublicKey([]byte(publicKey))
+	if err != nil {
+		log.Error("RSAEncryptByPublicKey rsaBytesToPublicKey err", log.E(err))
+		return err
+	}
+	h := hash.New()
+	h.Write(data)
+	hashed := make([]byte, 0)
+	hashed = h.Sum(hashed)
+	return rsa.VerifyPKCS1v15(pubKey, hash, hashed, sign)
+}
+
+// 公钥解密
+func RSADecryptByPrivateKey(pemPrivateKey []byte, cipherData []byte) ([]byte, error) {
+	privateKey, err := rsaBytesToPrivateKey(pemPrivateKey)
+	if err != nil {
+		log.Error("RSADecryptByPrivateKey rsaBytesToPrivateKey err", log.E(err))
+		return nil, err
+	}
+	blockLen := privateKey.N.BitLen() / 8
+	chunks := splitBytesSlice(cipherData, blockLen)
+	result := bytes.Buffer{}
+	for _, chunk := range chunks {
+		plain, err := rsa.DecryptPKCS1v15(rand.Reader, privateKey, chunk)
+		if err != nil {
+			log.Error("RSADecryptByPrivateKey DecryptPKCS1v15 err", log.E(err))
+			return nil, err
+		}
+		result.Write(plain)
+	}
+	return result.Bytes(), nil
+}
+
+// 公钥解密
+func RSADecryptByPrivateKey1(pemPrivateKey []byte, cipherData []byte) ([]byte, error) {
+	block, _ := pem.Decode(pemPrivateKey) //将密钥解析成私钥实例
+	if block == nil {
+		return nil, errors.New("private key error!")
+	}
+	priv, err := x509.ParsePKCS1PrivateKey(block.Bytes) //解析pem.Decode（）返回的Block指针实例
+	if err != nil {
+		return nil, err
+	}
+	return rsa.DecryptPKCS1v15(rand.Reader, priv, cipherData) //RSA算法解密
+}