rsa加密长度

❶ 请教基于java的rsa加密如何去掉加密明文长度的限制

既然高并发了务必要考虑吞吐量吧，进行同步不是一个好的选择。其实你可以把加密算法与私钥封装进一个类里，然后每次请求实例化这个类，创建一个实体，之后进行解密就行了。

❷ php中RSA加密，明文超长，需要分段加密该怎么做

这方面的话我不是很了解，一般来说，加密分为两个部分，一个是非对称加密，一个是对称加密，使用对称加密加密正文信息，使用非对称加密加密对称加密的密钥，然后发送加密数据(消息摘要和数字签名就不讨论了)，这是正规的数据加密策略，对称加密默认支持大数据分段加密策略，你只需要从接口中完成加密即可，而且对称加密速度比非对称加密快很多，如果你需要使用这个策略建议使用AES。
如果你不愿意使用对称加密，只愿意使用AES加密，那你就必须丧失速度了，而且自己处理分段加密，因为RSA加密通常是117个字节就要分段(这个长度可能和密钥长度有关，我是用的接口是117)，你需要自己把数据变成N个117字节的数据段来完成加密，解密也需要自己完成字节拼装。详细还是建议你去后盾人平台去看看视频教学吧，那里面有的，讲的很清楚。

❸ 1024位的RSA加密速度到2015年最快达到多少2048位的呢

RSA的算法现在基本是固定的，加密速度和你的硬件有关，硬件越好，速度越快。
虽然说RSA算是比较慢的一种加密算法了，但是他的安全性很好，几乎没有一种完善的破解方式，而且就目前来说，速度也还能接受，算是比较主流的一种数据加密方式。许多https证书加密就是RSA，而且是2048位的加密。
但要是说具体有多快就不清楚了。

❹ 有关C#中RSA加密方法的密钥生成长度

/// <summary> /// 字符串加密操作类
/// </summary>
public class EncryptionOperation
{
/// <summary>

/// MD5 加密静态方法
/// </summary>
/// <param name="EncryptString">待加密的密文</param>
/// <returns>returns</returns>
public static string MD5Encrypt(string EncryptString) {
if (string.IsNullOrEmpty(EncryptString)) { throw (new Exception("密文不得为空")); }

MD5 m_ClassMD5 = new MD5CryptoServiceProvider();

string m_strEncrypt = "";

try {
m_strEncrypt = BitConverter.ToString(m_ClassMD5.ComputeHash(Encoding.Default.GetBytes(EncryptString))).Replace("-", "");
}
catch (ArgumentException ex) { throw ex; }
catch (CryptographicException ex) { throw ex; }
catch (Exception ex) { throw ex; }
finally { m_ClassMD5.Clear(); }

return m_strEncrypt;
}

/// <summary>
/// DES 加密(数据加密标准，速度较快，适用于加密大量数据的场合)
/// </summary>
/// <param name="EncryptString">待加密的密文</param>
/// <param name="EncryptKey">加密的密钥</param>
/// <returns>returns</returns>
public static string DESEncrypt(string EncryptString, string EncryptKey) {
if (string.IsNullOrEmpty(EncryptString)) { throw (new Exception("密文不得为空")); }

if (string.IsNullOrEmpty(EncryptKey)) { throw (new Exception("密钥不得为空")); }

if (EncryptKey.Length != 8) { throw (new Exception("密钥必须为8位")); }

byte[] m_btIV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

string m_strEncrypt = "";

DESCryptoServiceProvider m_DESProvider = new DESCryptoServiceProvider();

try {
byte[] m_btEncryptString = Encoding.Default.GetBytes(EncryptString);

MemoryStream m_stream = new MemoryStream();

CryptoStream m_cstream = new CryptoStream(m_stream, m_DESProvider.CreateEncryptor(Encoding.Default.GetBytes(EncryptKey), m_btIV), CryptoStreamMode.Write);

m_cstream.Write(m_btEncryptString, 0, m_btEncryptString.Length);

m_cstream.FlushFinalBlock();

m_strEncrypt = Convert.ToBase64String(m_stream.ToArray());

m_stream.Close(); m_stream.Dispose();

m_cstream.Close(); m_cstream.Dispose();
}
catch (IOException ex) { throw ex; }
catch (CryptographicException ex) { throw ex; }
catch (ArgumentException ex) { throw ex; }
catch (Exception ex) { throw ex; }
finally { m_DESProvider.Clear(); }

return m_strEncrypt;
}
/// <summary>
/// DES 解密(数据加密标准，速度较快，适用于加密大量数据的场合)
/// </summary>
/// <param name="DecryptString">待解密的密文</param>
/// <param name="DecryptKey">解密的密钥</param>
/// <returns>returns</returns>
public static string DESDecrypt(string DecryptString, string DecryptKey) {
if (string.IsNullOrEmpty(DecryptString)) { throw (new Exception("密文不得为空")); }

if (string.IsNullOrEmpty(DecryptKey)) { throw (new Exception("密钥不得为空")); }

if (DecryptKey.Length != 8) { throw (new Exception("密钥必须为8位")); }

byte[] m_btIV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

string m_strDecrypt = "";

DESCryptoServiceProvider m_DESProvider = new DESCryptoServiceProvider();

try {
byte[] m_btDecryptString = Convert.FromBase64String(DecryptString);

MemoryStream m_stream = new MemoryStream();

CryptoStream m_cstream = new CryptoStream(m_stream, m_DESProvider.CreateDecryptor(Encoding.Default.GetBytes(DecryptKey), m_btIV), CryptoStreamMode.Write);

m_cstream.Write(m_btDecryptString, 0, m_btDecryptString.Length);

m_cstream.FlushFinalBlock();

m_strDecrypt = Encoding.Default.GetString(m_stream.ToArray());

m_stream.Close(); m_stream.Dispose();

m_cstream.Close(); m_cstream.Dispose();
}
catch (IOException ex) {
m_strDecrypt = "";
}

catch (CryptographicException ex) { m_strDecrypt = ""; }
catch (ArgumentException ex) { m_strDecrypt = ""; }
catch (Exception ex) { m_strDecrypt = ""; }
finally { m_DESProvider.Clear(); }

return m_strDecrypt;
}
/// <summary>
/// RC2 加密(用变长密钥对大量数据进行加密)
/// </summary>
/// <param name="EncryptString">待加密密文</param>
/// <param name="EncryptKey">加密密钥</param>
/// <returns>returns</returns>
public static string RC2Encrypt(string EncryptString, string EncryptKey) {
if (string.IsNullOrEmpty(EncryptString)) { throw (new Exception("密文不得为空")); }

if (string.IsNullOrEmpty(EncryptKey)) { throw (new Exception("密钥不得为空")); }

if (EncryptKey.Length < 5 || EncryptKey.Length > 16) { throw (new Exception("密钥必须为5-16位")); }

string m_strEncrypt = "";

byte[] m_btIV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

RC2CryptoServiceProvider m_RC2Provider = new RC2CryptoServiceProvider();

try {
byte[] m_btEncryptString = Encoding.Default.GetBytes(EncryptString);

MemoryStream m_stream = new MemoryStream();

CryptoStream m_cstream = new CryptoStream(m_stream, m_RC2Provider.CreateEncryptor(Encoding.Default.GetBytes(EncryptKey), m_btIV), CryptoStreamMode.Write);

m_cstream.Write(m_btEncryptString, 0, m_btEncryptString.Length);

m_cstream.FlushFinalBlock();

m_strEncrypt = Convert.ToBase64String(m_stream.ToArray());

m_stream.Close(); m_stream.Dispose();

m_cstream.Close(); m_cstream.Dispose();
}
catch (IOException ex) { throw ex; }
catch (CryptographicException ex) { throw ex; }
catch (ArgumentException ex) { throw ex; }
catch (Exception ex) { throw ex; }
finally { m_RC2Provider.Clear(); }

return m_strEncrypt;
}
/// <summary>
/// RC2 解密(用变长密钥对大量数据进行加密)
/// </summary>
/// <param name="DecryptString">待解密密文</param>
/// <param name="DecryptKey">解密密钥</param>
/// <returns>returns</returns>
public static string RC2Decrypt(string DecryptString, string DecryptKey) {
if (string.IsNullOrEmpty(DecryptString)) { throw (new Exception("密文不得为空")); }

if (string.IsNullOrEmpty(DecryptKey)) { throw (new Exception("密钥不得为空")); }

if (DecryptKey.Length < 5 || DecryptKey.Length > 16) { throw (new Exception("密钥必须为5-16位")); }

byte[] m_btIV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

string m_strDecrypt = "";

RC2CryptoServiceProvider m_RC2Provider = new RC2CryptoServiceProvider();

try {
byte[] m_btDecryptString = Convert.FromBase64String(DecryptString);

MemoryStream m_stream = new MemoryStream();

CryptoStream m_cstream = new CryptoStream(m_stream, m_RC2Provider.CreateDecryptor(Encoding.Default.GetBytes(DecryptKey), m_btIV), CryptoStreamMode.Write);

m_cstream.Write(m_btDecryptString, 0, m_btDecryptString.Length);

m_cstream.FlushFinalBlock();

m_strDecrypt = Encoding.Default.GetString(m_stream.ToArray());

m_stream.Close(); m_stream.Dispose();

m_cstream.Close(); m_cstream.Dispose();
}
catch (IOException ex) { throw ex; }
catch (CryptographicException ex) { throw ex; }
catch (ArgumentException ex) { throw ex; }
catch (Exception ex) { throw ex; }
finally { m_RC2Provider.Clear(); }
return m_strDecrypt;
}
/// <summary>
/// 3DES 加密(基于DES，对一块数据用三个不同的密钥进行三次加密，强度更高)
/// </summary>
/// <param name="EncryptString">待加密密文</param>
/// <param name="EncryptKey1">密钥一</param>
/// <param name="EncryptKey2">密钥二</param>
/// <param name="EncryptKey3">密钥三</param>
/// <returns>returns</returns>
public static string DES3Encrypt(string EncryptString, string EncryptKey1, string EncryptKey2, string EncryptKey3) {
string m_strEncrypt = "";

try {
m_strEncrypt = DESEncrypt(EncryptString, EncryptKey3);

m_strEncrypt = DESEncrypt(m_strEncrypt, EncryptKey2);

m_strEncrypt = DESEncrypt(m_strEncrypt, EncryptKey1);
}
catch (Exception ex) { throw ex; }

return m_strEncrypt;
}
/// <summary>
/// 3DES 解密(基于DES，对一块数据用三个不同的密钥进行三次加密，强度更高)
/// </summary>
/// <param name="DecryptString">待解密密文</param>
/// <param name="DecryptKey1">密钥一</param>
/// <param name="DecryptKey2">密钥二</param>
/// <param name="DecryptKey3">密钥三</param>
/// <returns>returns</returns>
public static string DES3Decrypt(string DecryptString, string DecryptKey1, string DecryptKey2, string DecryptKey3) {
string m_strDecrypt = "";

try {
m_strDecrypt = DESDecrypt(DecryptString, DecryptKey1);

m_strDecrypt = DESDecrypt(m_strDecrypt, DecryptKey2);

m_strDecrypt = DESDecrypt(m_strDecrypt, DecryptKey3);
}
catch (Exception ex) { throw ex; }

return m_strDecrypt;
}
/// <summary>
/// AES 加密(高级加密标准，是下一代的加密算法标准，速度快，安全级别高，目前 AES 标准的一个实现是 Rijndael 算法)
/// </summary>
/// <param name="EncryptString">待加密密文</param>
/// <param name="EncryptKey">加密密钥</param>
/// <returns></returns>
public static string AESEncrypt(string EncryptString, string EncryptKey) {
if (string.IsNullOrEmpty(EncryptString)) { throw (new Exception("密文不得为空")); }

if (string.IsNullOrEmpty(EncryptKey)) { throw (new Exception("密钥不得为空")); }

string m_strEncrypt = "";

byte[] m_btIV = Convert.FromBase64String("Rkb4jvUy/ye7Cd7k89QQgQ==");

Rijndael m_AESProvider = Rijndael.Create();

try {
byte[] m_btEncryptString = Encoding.Default.GetBytes(EncryptString);

MemoryStream m_stream = new MemoryStream();

CryptoStream m_csstream = new CryptoStream(m_stream, m_AESProvider.CreateEncryptor(Encoding.Default.GetBytes(EncryptKey), m_btIV), CryptoStreamMode.Write);

m_csstream.Write(m_btEncryptString, 0, m_btEncryptString.Length); m_csstream.FlushFinalBlock();

m_strEncrypt = Convert.ToBase64String(m_stream.ToArray());

m_stream.Close(); m_stream.Dispose();

m_csstream.Close(); m_csstream.Dispose();
}
catch (IOException ex) { throw ex; }
catch (CryptographicException ex) { throw ex; }
catch (ArgumentException ex) { throw ex; }
catch (Exception ex) { throw ex; }
finally { m_AESProvider.Clear(); }

return m_strEncrypt;
}
/// <summary>
/// AES 解密(高级加密标准，是下一代的加密算法标准，速度快，安全级别高，目前 AES 标准的一个实现是 Rijndael 算法)
/// </summary>
/// <param name="DecryptString">待解密密文</param>
/// <param name="DecryptKey">解密密钥</param>
/// <returns></returns>
public static string AESDecrypt(string DecryptString, string DecryptKey) {
if (string.IsNullOrEmpty(DecryptString)) { throw (new Exception("密文不得为空")); }

if (string.IsNullOrEmpty(DecryptKey)) { throw (new Exception("密钥不得为空")); }

string m_strDecrypt = "";

byte[] m_btIV = Convert.FromBase64String("Rkb4jvUy/ye7Cd7k89QQgQ==");

Rijndael m_AESProvider = Rijndael.Create();

try {
byte[] m_btDecryptString = Convert.FromBase64String(DecryptString);

MemoryStream m_stream = new MemoryStream();

CryptoStream m_csstream = new CryptoStream(m_stream, m_AESProvider.CreateDecryptor(Encoding.Default.GetBytes(DecryptKey), m_btIV), CryptoStreamMode.Write);

m_csstream.Write(m_btDecryptString, 0, m_btDecryptString.Length); m_csstream.FlushFinalBlock();

m_strDecrypt = Encoding.Default.GetString(m_stream.ToArray());

m_stream.Close(); m_stream.Dispose();

m_csstream.Close(); m_csstream.Dispose();
}
catch (IOException ex) { throw ex; }
catch (CryptographicException ex) { throw ex; }
catch (ArgumentException ex) { throw ex; }
catch (Exception ex) { throw ex; }
finally { m_AESProvider.Clear(); }

return m_strDecrypt;
} }

❺ php openssl rsa 加密长度大于117，返回false,无法加密，求解决办法

把你自己的字符串分开，每100个字符串成一个，然后分开加密相连，解密的时候也是如此

❻ RSA加密.秘钥长度2048是不是必须是实际数位正好达到2048

你说的对。

❼ DES、RSA的明文长度和密文长度分别是多少

加密的明文长度不能超过RSA密钥的长度-11，比如1024位的，明文长度不能超过117。 密文的长度总是密钥的长度的一半，比如1024位的，密文长度是64，如果是1032位，密文长度是65位。

❽ rsa中为什么加密后的长度不想同

RSA是一种块文件加密系统，他需要将输入的数据分成固定大小的块，然后对这些数据块进行加密。加密以后输出的数据块长度和输入时一样的。你发现加密后的长度不同的话，应该是RSA加密的那个padding（填充）配置不一样，从而使得每次加密数据块的长度不同，这样最后出来的长度也就不一样了。

❾ Rsa 算法加密的数据块大小问题

PQ的积M叫做模，模规定了这个数字空间中最大的数，是这个空间的边界，这个空间中所有的数都要小于模M，包括被加密的消息块。所以如果消息（a1,a2,a3...）任何一个超过了M，加密后都无法正切解密，因为加密后和解密后得到的数都在这个空间中，不可能得到一个大于M的数。

但是如果用来加密的消息A大于M，解密后得到的结果加上K倍的M一定会等于A，因为加密的过程是做模乘操作，大于M的消息A首先被除M然后取余数了，该余数一定小于M，然后所有的加密操作都是针对该余数来进行的，想要还原A的话用该A模M的余数加上数倍的M就可以了。解密的话还原的也是该余数，得到余数后还原A,也是加上数倍的M就可以了。

实质上RSA的加密有个条件，消息A必须要小于M。