c++ 引用openssl库进行签名、验证问题

[syao_zj]

问题： 数字签名时，不同的输入，部分输入验证会失败，部分输入验证成功，（感觉是数字签名的长度问题），请问下是什么原因导致的呢，该如何解决呢，使用的 SHA1withRSA 签名
执行结果在截图中

string COpenSslApi::signedRSA(const string& sMsg, const string& sPirvateKeyPath, const E_ALGO& eAlgo)
{
    BIO                 *bufio  = NULL;         //密钥缓存buff
    RSA                 *rsa    = NULL;         //rsa结构变量      
    EVP_PKEY            *evpKey = NULL;		    //EVP KEY结构体变量
    const EVP_MD*       e_algo  = nullptr;      //摘要算法  支持sha1 md5等，具体参见枚举
    EVP_MD_CTX          *mdctx  = NULL;		    //摘要上下文变量
    unsigned char*      pSign   = nullptr;      //加密后的内容
    unsigned int        iSignLen= 0;            //sign长度
    string              sSignRet;               //返回值
    
    try
    { 
        //入参判断
        if (sMsg.empty() || sPirvateKeyPath.empty())
        {
            cout << "empty msg or keypath" << endl;
            goto safe_exit;
       }
        //打开密钥文件buff
        bufio = BIO_new(BIO_s_file());
        BIO_read_filename(bufio, sPirvateKeyPath.c_str());
        if(bufio == NULL)
        {
            cout <<"BIO_read_filename error" <<endl;
            goto safe_exit;
        }
        //获取rsa
        rsa = PEM_read_bio_RSAPrivateKey(bufio, NULL, NULL, NULL);
        if (rsa == NULL)
        {
            cout << "PEM_read_bio_RSAPrivateKey error" << endl;
            goto safe_exit;
        }
        //evp_key结构变量初始化
        evpKey = EVP_PKEY_new();
        if (evpKey == NULL)
        {
            cout << "EVP_PKEY_new error" << endl;
            goto safe_exit;
        }
        //保存RSA结构体到EVP_PKEY结构体
        if (EVP_PKEY_set1_RSA(evpKey, rsa) != 1)
        {
            cout << "EVP_PKEY_set1_RSA error" << endl;
            goto safe_exit;
        }
        //初始化摘要上下文
        mdctx = EVP_MD_CTX_new();
        if(mdctx == NULL)
        {
            cout <<"EVP_MD_CTX_new error" <<endl;
            goto safe_exit;
        }
        EVP_MD_CTX_init(mdctx);
        switch(eAlgo)
        {
            case E_SHA1:
                e_algo = EVP_sha1();
                break;
            case E_MD5:
                e_algo = EVP_md5();
                break;
            default:
                break;
        }
        //签名初始化，设置摘要算法
        if(!EVP_SignInit_ex(mdctx, e_algo, NULL)) 
        {
            cout <<"EVP_SignInit_ex error" <<endl;
            goto safe_exit;
        }
        cout << "input_msg="<< sMsg.c_str() <<"|leng="<< sMsg.length() <<endl;  
        //计算签名（摘要）Update
        if(!EVP_SignUpdate(mdctx, sMsg.c_str() , sMsg.length() ))
        {
            cout <<"EVP_SignUpdate error" <<endl;
            goto safe_exit;
        }
        //申请内存
        iSignLen = EVP_PKEY_size(evpKey);
        pSign = (unsigned char*)malloc(iSignLen+1);
        memset(pSign, 0, iSignLen+1);
        if( pSign == nullptr || iSignLen == 0)
        {
            cout <<"EVP_SignFinal error" <<endl;
            goto safe_exit;   
        }
        cout << "EVP_PKEY.length = " << iSignLen <<endl;
        //签名输出
        if(!EVP_SignFinal(mdctx,pSign,&iSignLen,evpKey) )
        {
            cout <<"EVP_SignFinal error" <<endl;
            goto safe_exit;
        }
        cout << "[after sign]signature.size=" << strlen((char*)pSign) <<endl;
        sSignRet = (char *)pSign;

    safe_exit:
        if (mdctx)
        {
            EVP_MD_CTX_reset(mdctx);
            EVP_MD_CTX_free(mdctx);  
            mdctx = NULL;          
        }
        //EVP_MD_CTX_cleanup(mdctx);
        if (bufio)
        {
            BIO_free_all(bufio);
            bufio = NULL;
        }
        if (rsa)
        {
            RSA_free(rsa);
            rsa = NULL;
        }
        if (evpKey)
        {
            EVP_PKEY_free(evpKey);
            evpKey = NULL;
        }
        if (pSign)
        {
            free(pSign);
            pSign = NULL;
        }
    }
    catch(const std::exception& e)
    {
        std::cout << e.what() << '\n';
    }
    

    return std::move(sSignRet);
}

[syao_zj]

https://www.kancloud.cn/kancloud/rsa_algorithm/48484