【go语言】RSA加解密

关于go语言的RSA加解密的介绍，这里有一篇文章，已经介绍的很完整了。

对应的go语言的加解密代码，参考git。

因为原文跨语言是跟php，我这里要跟c语言进行交互，所以，这里贴上c语言的例子。

参考原文：http://hayageek.com/rsa-encryption-decryption-openssl-c/

#include <openssl/pem.h>
#include <openssl/ssl.h>
#include <openssl/rsa.h>
#include <openssl/evp.h>
#include <openssl/bio.h>
#include <openssl/err.h>
#include <openssl/buffer.h>

#include <stdio.h>
#include <stdint.h>


//编译
//gcc rsa_example.c -o example -L/usr/local/Cellar/openssl/1.0.2e/lib/ -lssl -lcrypto

//openssl的base64编解码: https://gist.github.com/barrysteyn/7308212
int Base64Encode(const unsigned char* buffer, size_t length, char** b64text) { 
    BIO *bio, *b64;
    BUF_MEM *bufferPtr;

    b64 = BIO_new(BIO_f_base64());
    bio = BIO_new(BIO_s_mem());
    bio = BIO_push(b64, bio);

    BIO_set_flags(bio, BIO_FLAGS_BASE64_NO_NL); 
    BIO_write(bio, buffer, length);
    BIO_flush(bio);
    BIO_get_mem_ptr(bio, &bufferPtr);
    BIO_set_close(bio, BIO_NOCLOSE);
    BIO_free_all(bio);

    *b64text=(*bufferPtr).data;

    return (0); //success
}

int padding = RSA_PKCS1_PADDING;
 
RSA * createRSA(unsigned char * key,int public)
{
    RSA *rsa= NULL;
    BIO *keybio ;
    keybio = BIO_new_mem_buf(key, -1);
    if (keybio==NULL)
    {
        printf( "Failed to create key BIO");
        return 0;
    }
    if(public)
    {
        rsa = PEM_read_bio_RSA_PUBKEY(keybio, &rsa,NULL, NULL);
    }
    else
    {
        rsa = PEM_read_bio_RSAPrivateKey(keybio, &rsa,NULL, NULL);
    }
    if(rsa == NULL)
    {
        printf( "Failed to create RSA");
    }
 
    return rsa;
}
 
int public_encrypt(unsigned char * data,int data_len,unsigned char * key, unsigned char *encrypted)
{
    RSA * rsa = createRSA(key,1);
    int result = RSA_public_encrypt(data_len,data,encrypted,rsa,padding);
    return result;
}
int private_decrypt(unsigned char * enc_data,int data_len,unsigned char * key, unsigned char *decrypted)
{
    RSA * rsa = createRSA(key,0);
    int  result = RSA_private_decrypt(data_len,enc_data,decrypted,rsa,padding);
    return result;
}
 
 
int private_encrypt(unsigned char * data,int data_len,unsigned char * key, unsigned char *encrypted)
{
    RSA * rsa = createRSA(key,0);
    int result = RSA_private_encrypt(data_len,data,encrypted,rsa,padding);
    return result;
}
int public_decrypt(unsigned char * enc_data,int data_len,unsigned char * key, unsigned char *decrypted)
{
    RSA * rsa = createRSA(key,1);
    int  result = RSA_public_decrypt(data_len,enc_data,decrypted,rsa,padding);
    return result;
}
 
void printLastError(char *msg)
{
    char * err = malloc(130);;
    ERR_load_crypto_strings();
    ERR_error_string(ERR_get_error(), err);
    printf("%s ERROR: %s
",msg, err);
    free(err);
}
 
int main(){
 
 char plainText[2048/8] = "1024"; //原始数据为字符串1024；key length : 2048, 数据最长为 keylen/8个char
 
 char publicKey[]="-----BEGIN PUBLIC KEY-----
"
"MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAy8Dbv8prpJ/0kKhlGeJY
"
"ozo2t60EG8L0561g13R29LvMR5hyvGZlGJpmn65+A4xHXInJYiPuKzrKUnApeLZ+
"
"vw1HocOAZtWK0z3r26uA8kQYOKX9Qt/DbCdvsF9wF8gRK0ptx9M6R13NvBxvVQAp
"
"fc9jB9nTzphOgM4JiEYvlV8FLhg9yZovMYd6Wwf3aoXK891VQxTr/kQYoq1Yp+68
"
"i6T4nNq7NWC+UNVjQHxNQMQMzU6lWCX8zyg3yH88OAQkUXIXKfQ+NkvYQ1cxaMoV
"
"PpY72+eVthKzpMeyHkBn7ciumk5qgLTEJAfWZpe4f4eFZj/Rc8Y8Jj2IS5kVPjUy
"
"wQIDAQAB
"
"-----END PUBLIC KEY-----
";
  
 char privateKey[]="-----BEGIN RSA PRIVATE KEY-----
"
"MIIEowIBAAKCAQEAy8Dbv8prpJ/0kKhlGeJYozo2t60EG8L0561g13R29LvMR5hy
"
"vGZlGJpmn65+A4xHXInJYiPuKzrKUnApeLZ+vw1HocOAZtWK0z3r26uA8kQYOKX9
"
"Qt/DbCdvsF9wF8gRK0ptx9M6R13NvBxvVQApfc9jB9nTzphOgM4JiEYvlV8FLhg9
"
"yZovMYd6Wwf3aoXK891VQxTr/kQYoq1Yp+68i6T4nNq7NWC+UNVjQHxNQMQMzU6l
"
"WCX8zyg3yH88OAQkUXIXKfQ+NkvYQ1cxaMoVPpY72+eVthKzpMeyHkBn7ciumk5q
"
"gLTEJAfWZpe4f4eFZj/Rc8Y8Jj2IS5kVPjUywQIDAQABAoIBADhg1u1Mv1hAAlX8
"
"omz1Gn2f4AAW2aos2cM5UDCNw1SYmj+9SRIkaxjRsE/C4o9sw1oxrg1/z6kajV0e
"
"N/t008FdlVKHXAIYWF93JMoVvIpMmT8jft6AN/y3NMpivgt2inmmEJZYNioFJKZG
"
"X+/vKYvsVISZm2fw8NfnKvAQK55yu+GRWBZGOeS9K+LbYvOwcrjKhHz66m4bedKd
"
"gVAix6NE5iwmjNXktSQlJMCjbtdNXg/xo1/G4kG2p/MO1HLcKfe1N5FgBiXj3Qjl
"
"vgvjJZkh1as2KTgaPOBqZaP03738VnYg23ISyvfT/teArVGtxrmFP7939EvJFKpF
"
"1wTxuDkCgYEA7t0DR37zt+dEJy+5vm7zSmN97VenwQJFWMiulkHGa0yU3lLasxxu
"
"m0oUtndIjenIvSx6t3Y+agK2F3EPbb0AZ5wZ1p1IXs4vktgeQwSSBdqcM8LZFDvZ
"
"uPboQnJoRdIkd62XnP5ekIEIBAfOp8v2wFpSfE7nNH2u4CpAXNSF9HsCgYEA2l8D
"
"JrDE5m9Kkn+J4l+AdGfeBL1igPF3DnuPoV67BpgiaAgI4h25UJzXiDKKoa706S0D
"
"4XB74zOLX11MaGPMIdhlG+SgeQfNoC5lE4ZWXNyESJH1SVgRGT9nBC2vtL6bxCVV
"
"WBkTeC5D6c/QXcai6yw6OYyNNdp0uznKURe1xvMCgYBVYYcEjWqMuAvyferFGV+5
"
"nWqr5gM+yJMFM2bEqupD/HHSLoeiMm2O8KIKvwSeRYzNohKTdZ7FwgZYxr8fGMoG
"
"PxQ1VK9DxCvZL4tRpVaU5Rmknud9hg9DQG6xIbgIDR+f79sb8QjYWmcFGc1SyWOA
"
"SkjlykZ2yt4xnqi3BfiD9QKBgGqLgRYXmXp1QoVIBRaWUi55nzHg1XbkWZqPXvz1
"
"I3uMLv1jLjJlHk3euKqTPmC05HoApKwSHeA0/gOBmg404xyAYJTDcCidTg6hlF96
"
"ZBja3xApZuxqM62F6dV4FQqzFX0WWhWp5n301N33r0qR6FumMKJzmVJ1TA8tmzEF
"
"yINRAoGBAJqioYs8rK6eXzA8ywYLjqTLu/yQSLBn/4ta36K8DyCoLNlNxSuox+A5
"
"w6z2vEfRVQDq4Hm4vBzjdi3QfYLNkTiTqLcvgWZ+eX44ogXtdTDO7c+GeMKWz4XX
"
"uJSUVL5+CVjKLjZEJ6Qc2WZLl94xSwL71E41H4YciVnSCQxVc4Jw
"
"-----END RSA PRIVATE KEY-----
";
 
    
unsigned char  encrypted[4098]={};
unsigned char decrypted[4098]={};
 
int encrypted_length= public_encrypt(plainText,strlen(plainText),publicKey,encrypted);
if(encrypted_length == -1)
{
    printLastError("Public Encrypt failed ");
    exit(0);
}
printf("Encrypted length =%d
",encrypted_length);

char *b64text;

Base64Encode( encrypted, encrypted_length, &b64text);
printf("Base64Encode = %s
", b64text);


int decrypted_length = private_decrypt(encrypted,encrypted_length,privateKey, decrypted);
if(decrypted_length == -1)
{
    printLastError("Private Decrypt failed ");
    exit(0);
}
printf("Decrypted Text =%s
",decrypted);
printf("Decrypted Length =%d
",decrypted_length);
 
 
encrypted_length= private_encrypt(plainText,strlen(plainText),privateKey,encrypted);
if(encrypted_length == -1)
{
    printLastError("Private Encrypt failed");
    exit(0);
}
printf("Encrypted length =%d
",encrypted_length);
 
decrypted_length = public_decrypt(encrypted,encrypted_length,publicKey, decrypted);
if(decrypted_length == -1)
{
    printLastError("Public Decrypt failed");
    exit(0);
}
printf("Decrypted Text =%s
",decrypted);
printf("Decrypted Length =%d
",decrypted_length);
 
}

编译执行之后，可以得到加密之后的base64数据：

./example
Encrypted length =256
Base64Encode = BXFuS6snRRhYUQhTYKG00UoGMzaptbZpaw7h+JEA+yP1sEd5dXaBEjdzzZ8jXRVfjigYFj41zEBSDsafxO440+vi/aODOAY1f4Q2dKf5eBLnXDyN9uT6uxCp67XgZC3YkN+iufMOKIEjSbb361kZrRLwl+6OUt4EYvkhmKl5YpklM+qQYyGW5xyCU5MYMUTXJoAthRTeNuoloSiZDQWKPH4i7bVfR/XDjXIA3iNWfoy5552L4AdtyRhRNvZ0RerbVtPqdWABvJX39hbskmGuzY9HtoxOQaoD0IWGHx29VmCM3JRrTvStnEKjYnUNT9ikbeK1gXX5JjU6HmLHbgPKUg==
Decrypted Text =1024
Decrypted Length =4
Encrypted length =256
Decrypted Text =1024
Decrypted Length =4

把base64数据，传递给go语言（这里需要把对应的go语言的公钥、私钥替换成c语言中的示例），用私钥进行解密，可以得到对应的原始数据，这样验证 c 和 go之间的加解密OK。

go run rsa.go -d BXFuS6snRRhYUQhTYKG00UoGMzaptbZpaw7h+JEA+yP1sEd5dXaBEjdzzZ8jXRVfjigYFj41zEBSDsafxO440+vi/aODOAY1f4Q2dKf5eBLnXDyN9uT6uxCp67XgZC3YkN+iufMOKIEjSbb361kZrRLwl+6OUt4EYvkhmKl5YpklM+qQYyGW5xyCU5MYMUTXJoAthRTeNuoloSiZDQWKPH4i7bVfR/XDjXIA3iNWfoy5552L4AdtyRhRNvZ0RerbVtPqdWABvJX39hbskmGuzY9HtoxOQaoD0IWGHx29VmCM3JRrTvStnEKjYnUNT9ikbeK1gXX5JjU6HmLHbgPKUg==
[1024]