go语言RSA分段加密V2501，GOLANG，RSA/ECB/PKCS1Padding。
加密解析：
//假设私钥长度为1024， 1024/8-11=117。
//如果明文的长度小于117，直接全加密，然后转base64。(data.Length <= maxBlockSize)
//如果明文长度大于117，则每117分一段加密，
publicKey.Size()刚好是（私钥长度/8）。privateKey.Size() 也一样。
解密解析：
//假设私钥长度为1024， 1024/8 =128。
//如果明文的长度小于 128，直接全解密。(data.Length <= maxBlockSize)
//如果明文长度大于 128，则每 128 分一段解密，
用“支付宝开放平台开发助手”生成一组公私钥：
PKCS8私钥：
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
与之匹配的 PKCS1 私钥，用助手转换的：
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
与之匹配的公钥：
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDM9As4OkFLUyEmtqVJJaHkAf0xKR3aq38q6FqSi1vQfy1hUjhh/Z8k5NaT2WnmnchGUOoGsvwtKVAHrS62qvWzAPy7sauvG/O7hu1l+3SsrRDtv/O6hqRjEbPex/hpZM1opdkDtiiuHB5wHFYnD7JouWme9lNAViRcj4bXfqnZqwIDAQAB
核心重点是拿到 GO 的 *rsa.PublicKey 、*rsa.PrivateKey 2个对象。
注意：和C#一样，公钥要还原为完整格式。
-----BEGIN PUBLIC KEY----- MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDM9As4OkFLUyEmtqVJJaHkAf0x KR3aq38q6FqSi1vQfy1hUjhh/Z8k5NaT2WnmnchGUOoGsvwtKVAHrS62qvWzAPy7 sauvG/O7hu1l+3SsrRDtv/O6hqRjEbPex/hpZM1opdkDtiiuHB5wHFYnD7JouWme 9lNAViRcj4bXfqnZqwIDAQAB -----END PUBLIC KEY-----
否则转成 *rsa.PublicKey 时会报错。
代码：
package main
import (
"bytes"
"crypto/rand"
"crypto/rsa"
"crypto/x509"
"encoding/base64"
"encoding/pem"
"fmt"
"log"
"strings"
)
func main() {
strOrg := "This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07.This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07。测试123abc"
log.Println("待加密的字符串：", strOrg)
strPrivateKeyPKCS1 := "MIICXwIBAAKBgQDM9As4OkFLUyEmtqVJJaHkAf0xKR3aq38q6FqSi1vQfy1hUjhh/Z8k5NaT2WnmnchGUOoGsvwtKVAHrS62qvWzAPy7sauvG/O7hu1l+3SsrRDtv/O6hqRjEbPex/hpZM1opdkDtiiuHB5wHFYnD7JouWme9lNAViRcj4bXfqnZqwIDAQABAoGBAL1uu4gG4B7dAQElQ/Qt4ko6RGlR1ZQteuaPyFc2k3BMfAc91XtMzfFtyZ7yDt3m7BuB4iy69jZPvva5bTnNHjXhjL+xdXvzhaLdcDdDjerNYOG2Idc+VM/BXGIjFnKhxyAq8fqEhXivcfiNmYHu3p0F3LFZ6hIZu+2ROWHM0q8hAkEA/ZwefHuXn2HIRfnGG5lEYqF9fHFDLoUGwfQKtjeeXHevPS4N+Smak/CUE6f/LUEnQiRvHdp1PFSrKVCkxALmgwJBAM7iiCKHPT1Sb8vdC4SDwPXNUvATwiOxDAmk2aieaN1Wkdnar1GQxl+5C95GJEPp+5qtyiBAr5BBcwPhTj/el7kCQQCUEyh1tE/2HkiqGslB6f5UvEehdhwsuD0W15+9fsH26WanCRHdjh4UDN7YjzldufHrG4zJWHklDaaWS+C4FZ1zAkEAuy77PUJfhjwwKqO06BDNZZiAkfdOkDyAR7l/tbCd8KWDETlrpsD2u2UR9+o+pbPukeTsHIJqVnrhNYGE6wTbAQJBAJ9qRLQJY19X6EH3+gi6M2IPyeifUZlRXCeqs9C199OdqjRQUGMPAjBwe1ZFTc7AyAwvC1+bj9qc063Ty3sPqTw="
strPublicKey := "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDM9As4OkFLUyEmtqVJJaHkAf0xKR3aq38q6FqSi1vQfy1hUjhh/Z8k5NaT2WnmnchGUOoGsvwtKVAHrS62qvWzAPy7sauvG/O7hu1l+3SsrRDtv/O6hqRjEbPex/hpZM1opdkDtiiuHB5wHFYnD7JouWme9lNAViRcj4bXfqnZqwIDAQAB"
//和C#一样，公钥要还原为完整格式。
strPublicKey2 := PubKeyFullToPure(strPublicKey) //格式化为纯字符串
strPublicKey2 = PubKeyPureStrToFull(strPublicKey2) //还原为完整格式
fmt.Println("公钥完整格式:\n", strPublicKey2)
rsaPub, err := convertPEMToRSAPublicKey(strPublicKey2) //从字符串转换为“公钥对象”
if err != nil {
log.Println("转换公钥时出错：", err)
return
}
log.Println("私钥长度：", rsaPub.N.BitLen())
privateKeyBytes, _ := base64.StdEncoding.DecodeString(strPrivateKeyPKCS1)
privateKey, err := x509.ParsePKCS1PrivateKey(privateKeyBytes)
if err != nil {
log.Println("转换私钥时出错：", err)
return
}
bData, err := RsaEncryptBlock([]byte(strOrg), rsaPub)
if err != nil {
log.Println("加密时出错：", err)
}
encryptedString := base64.StdEncoding.EncodeToString(bData)
fmt.Println("密文：")
fmt.Println(encryptedString)
byteDecode, _ := base64.StdEncoding.DecodeString(encryptedString)
dData, err2 := RsaDecryptBlock(byteDecode, privateKey)
if err2 == nil {
fmt.Println("解密出的内容：")
fmt.Println(string(dData))
} else {
log.Println("解密时出错：", err2)
}
}
// 格式化为纯字符串
func PubKeyFullToPure(pubKeyStr string) string {
a := strings.ReplaceAll(pubKeyStr, "-----BEGIN PUBLIC KEY-----", "")
a = strings.ReplaceAll(a, "-----END PUBLIC KEY-----", "")
a = strings.ReplaceAll(a, "\n", "")
return a
}
// 将 PEM 格式的公钥字符串转换为 rsa.PublicKey
func convertPEMToRSAPublicKey(pemStr string) (*rsa.PublicKey, error) {
// 解码 PEM 格式的字符串
block, _ := pem.Decode([]byte(pemStr))
if block == nil || block.Type != "PUBLIC KEY" {
return nil, fmt.Errorf("failed to decode PEM block containing the public key")
}
// 解析公钥
pub, err := x509.ParsePKIXPublicKey(block.Bytes)
if err != nil {
return nil, err
}
// 类型断言为 rsa.PublicKey
rsaPub, ok := pub.(*rsa.PublicKey)
if !ok {
return nil, fmt.Errorf("not a valid RSA public key")
}
return rsaPub, nil
}
// 还原为完整格式
func PubKeyPureStrToFull(pubKeyStr string) string {
// 获取公钥字符串的长度
nKeyLen := len(pubKeyStr)
var finalBuffer bytes.Buffer
finalBuffer.WriteString("-----BEGIN PUBLIC KEY-----\n")
// 由于我们已经知道要在每 64 个字符后插入换行符，我们可以直接这样做：
for i := 0; i < nKeyLen; i += 64 {
end := i + 64
if end > nKeyLen {
end = nKeyLen
}
currLine := pubKeyStr[i:end]
finalBuffer.WriteString(currLine)
finalBuffer.WriteString("\n")
}
// 写入尾部
finalBuffer.WriteString("-----END PUBLIC KEY-----\n")
// 获取最终的字符串
allKeyStr := finalBuffer.String()
return allKeyStr
}
/*
*
公钥加密-分段
*/
func RsaEncryptBlock(src []byte, publicKey *rsa.PublicKey) (bytesEncrypt []byte, err error) {
keySize, srcSize := publicKey.Size(), len(src)
//单次加密的长度 私钥长度/8 -11 。私钥长度，如：1024、2048。 publicKey.Size()刚好是（私钥长度/8）。
offSet, blockSize := 0, keySize-11
buffer := bytes.Buffer{}
for offSet < srcSize {
endIndex := offSet + blockSize
if endIndex > srcSize {
endIndex = srcSize
}
// 加密一部分
bytesOnce, err := rsa.EncryptPKCS1v15(rand.Reader, publicKey, src[offSet:endIndex])
if err != nil {
return nil, err
}
buffer.Write(bytesOnce)
offSet = endIndex
}
bytesEncrypt = buffer.Bytes()
return
}
/*
*
私钥解密-分段
*/
func RsaDecryptBlock(src []byte, privateKey *rsa.PrivateKey) (bytesDecrypt []byte, err error) {
//分段解密，单块长度是（私钥长度/8），privateKey.Size()正好是（私钥长度/8）。
blockSize := privateKey.Size()
srcSize := len(src)
// log.Println("密钥长度：", blockSize, "\t密文长度：\t", srcSize)
var offSet = 0
var buffer = bytes.Buffer{}
for offSet < srcSize {
endIndex := offSet + blockSize
if endIndex > srcSize {
endIndex = srcSize
}
bytesOnce, err := rsa.DecryptPKCS1v15(rand.Reader, privateKey, src[offSet:endIndex])
if err != nil {
return nil, err
}
buffer.Write(bytesOnce)
offSet = endIndex
}
bytesDecrypt = buffer.Bytes()
return
}
运行结果：
2025/01/09 13:39:51 待加密的字符串： This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07.This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07。测试123abc 2025/01/09 13:39:51 私钥长度： 1024 密文： 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 解密出的内容： This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07.This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07This is a very long message that needs to be encrypted using RSA in multiple parts.中华人民共和国2025-01-07。测试123abc
--
标签：私钥,err,nil,V2501,RSA,-----,go,return From： https://www.cnblogs.com/runliuv/p/18662005