這幾天在寫一個安卓的RSA公鑰加密算法，用于跟PHP后臺接口進(jìn)行交互晓淀。在實踐過程中發(fā)現(xiàn)了幾個坑所袁。其中我的公鑰和私鑰都是通過openssl生成的pem格式。
遇到的坑：
1.通過java的RSA公鑰加密后獲得的密文凶掰，在PHP中無法解密
2.通過java提取私鑰時報錯私鑰格式不對
以下是相關(guān)關(guān)鍵代碼[不完善的示例代碼]
（該代碼可直接百度燥爷，一大堆）
1.公鑰私鑰
<pre>
static String PUCLIC_KEY = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCfRTdcPIH10gT9f31rQuIInLwe" + "\r"
+ "7fl2dtEJ93gTmjE9c2H+kLVENWgECiJVQ5sonQNfwToMKdO0b3Olf4pgBKeLThra" + "\r"
+ "z/L3nYJYlbqjHC3jTjUnZc0luumpXGsox62+PuSGBlfb8zJO6hix4GV/vhyQVCpG" + "\r"
+ "9aYqgE7zyTRZYX9byQIDAQAB" + "\r";
static String PRIVATE_KEY = "MIICdwIBADANBgkqhkiG9w0BAQEFAASCAmEwggJdAgEAAoGBAJ9FN1w8gfXSBP1/" + "\r"
+ "fWtC4gicvB7t+XZ20Qn3eBOaMT1zYf6QtUQ1aAQKIlVDmyidA1/BOgwp07Rvc6V/" + "\r"
+ "imAEp4tOGtrP8vedgliVuqMcLeNONSdlzSW66alcayjHrb4+5IYGV9vzMk7qGLHg" + "\r"
+ "ZX++HJBUKkb1piqATvPJNFlhf1vJAgMBAAECgYA736xhG0oL3EkN9yhx8zG/5RP/" + "\r"
+ "WJzoQOByq7pTPCr4m/Ch30qVerJAmoKvpPumN+h1zdEBk5PHiAJkm96sG/PTndEf" + "\r"
+ "kZrAJ2hwSBqptcABYk6ED70gRTQ1S53tyQXIOSjRBcugY/21qeswS3nMyq3xDEPK" + "\r"
+ "XpdyKPeaTyuK86AEkQJBAM1M7p1lfzEKjNw17SDMLnca/8pBcA0EEcyvtaQpRvaL" + "\r"
+ "n61eQQnnPdpvHamkRBcOvgCAkfwa1uboru0QdXii/gUCQQDGmkP+KJPX9JVCrbRt" + "\r"
+ "7wKyIemyNM+J6y1ZBZ2bVCf9jacCQaSkIWnIR1S9UM+1CFE30So2CA0CfCDmQy+y" + "\r"
+ "7A31AkB8cGFB7j+GTkrLP7SX6KtRboAU7E0q1oijdO24r3xf/Imw4Cy0AAIx4KAu" + "\r"
+ "L29GOp1YWJYkJXCVTfyZnRxXHxSxAkEAvO0zkSv4uI8rDmtAIPQllF8+eRBT/deD" + "\r"
+ "JBR7ga/k+wctwK/Bd4Fxp9xzeETP0l8/I+IOTagK+Dos8d8oGQUFoQJBAI4Nwpfo" + "\r"
+ "MFaLJXGY9ok45wXrcqkJgM+SN6i8hQeujXESVHYatAIL/1DgLi+u46EFD69fw0w+" + "\r" + "c7o0HLlMsYPAzJw="
+ "\r";
</pre>
2.獲取公鑰并加密（PHP解密密文失敗）
<pre>
String source = "hello world";
PublicKey publicKey = RSAUtils.loadPublicKey(PUCLIC_KEY);
byte[] encryptByte = RSAUtils.encryptData(source.getBytes(), publicKey);
String afterencrypt = Base64Utils.encode(encryptByte);
</pre>
3.獲取私鑰并解密（私鑰獲取失斉尘健）
<pre>
PrivateKey privateKey = RSAUtils.loadPrivateKey(PRIVATE_KEY);
byte[] b1 = afterencrypt.getBytes();
String text = new String(RSAUtils.decryptData(encryptByte, privateKey));
</pre>
4.RSA算法工具類RSAUtils.class[不完善的示例代碼]
<pre>
public final class RSAUtils
{
static String RSA = "RSA";
public static byte[] encryptData(byte[] data, PublicKey publicKey) throws Exception
{
try
{
Cipher cipher = Cipher.getInstance(RSA);
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
return cipher.doFinal(data);
} catch (NoSuchAlgorithmException e) {
throw new Exception("無此解密算法");
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null;
}catch (InvalidKeyException e) {
throw new Exception("解密私鑰非法,請檢查");
} catch (IllegalBlockSizeException e) {
throw new Exception("密文長度非法");
} catch (BadPaddingException e) {
throw new Exception("密文數(shù)據(jù)已損壞");
}
}
public static byte[] decryptData(byte[] encryptedData, PrivateKey privateKey) throws Exception
{
try
{
Cipher cipher = Cipher.getInstance(RSA);
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return cipher.doFinal(encryptedData);
} catch (NoSuchAlgorithmException e) {
throw new Exception("無此解密算法");
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null;
}catch (InvalidKeyException e) {
throw new Exception("解密私鑰非法,請檢查");
} catch (IllegalBlockSizeException e) {
throw new Exception("密文長度非法");
} catch (BadPaddingException e) {
throw new Exception("密文數(shù)據(jù)已損壞");
}
}
public static PublicKey getPublicKey(byte[] keyBytes) throws NoSuchAlgorithmException,
InvalidKeySpecException
{
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
PublicKey publicKey = keyFactory.generatePublic(keySpec);
return publicKey;
}
public static PrivateKey getPrivateKey(byte[] keyBytes) throws NoSuchAlgorithmException,
InvalidKeySpecException
{
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
return privateKey;
}
public static PublicKey loadPublicKey(String publicKeyStr) throws Exception
{
try
{
byte[] buffer = Base64Utils.decode(publicKeyStr);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
return (RSAPublicKey) keyFactory.generatePublic(keySpec);
} catch (NoSuchAlgorithmException e)
{
throw new Exception("not this suanfa");
} catch (InvalidKeySpecException e)
{
throw new Exception("invalid public key");
} catch (NullPointerException e)
{
throw new Exception("public key is null");
}
}
public static PrivateKey loadPrivateKey(String privateKeyStr) throws Exception
{
try
{
byte[] buffer = Base64Utils.decode(privateKeyStr);
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
} catch (NoSuchAlgorithmException e)
{
throw new Exception("not this suanfa");
} catch (InvalidKeySpecException e)
{
throw new Exception("invalid private key");
} catch (NullPointerException e)
{
throw new Exception("private key is null");
}
}
}
</pre>
問題解決（填坑）
1.通過java的RSA公鑰加密后獲得的密文前翎，在PHP中無法解密是因為JAVA和PHP加密模式和填充方式?jīng)]有統(tǒng)一
2.通過java提取私鑰時報錯私鑰格式不對，這個時候需要引入第三方算法提供商BouncyCastleProvider
于是乎
針對問題一畅涂，將加密過程RSAUtils.class中的公鑰加密函數(shù)encryptData()中的算法實例獲取
<pre>
Cipher cipher = Cipher.getInstance(RSA);
</pre>
改成
<pre>
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
</pre>
即指定了ECB加密模式以及PKCS1Padding填充方式
針對問題二港华，在RSAUtils.class中的私鑰加載函數(shù)loadPublicKey()中加入第三方算法提供商，以統(tǒng)一格式
<pre>
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
</pre>
改成
<pre>
KeyFactory keyFactory = KeyFactory.getInstance(RSA, new BouncyCastleProvider());
</pre>
RSA算法工具類RSAUtils.class（完善版）
<pre>
public final class RSAUtils
{
static String RSA = "RSA";
public static byte[] encryptData(byte[] data, PublicKey publicKey) throws Exception
{
try
{
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
return cipher.doFinal(data);
} catch (NoSuchAlgorithmException e) {
throw new Exception("無此解密算法");
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null;
}catch (InvalidKeyException e) {
throw new Exception("解密私鑰非法,請檢查");
} catch (IllegalBlockSizeException e) {
throw new Exception("密文長度非法");
} catch (BadPaddingException e) {
throw new Exception("密文數(shù)據(jù)已損壞");
}
}
public static byte[] decryptData(byte[] encryptedData, PrivateKey privateKey) throws Exception
{
try
{
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return cipher.doFinal(encryptedData);
} catch (NoSuchAlgorithmException e) {
throw new Exception("無此解密算法");
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null;
}catch (InvalidKeyException e) {
throw new Exception("解密私鑰非法,請檢查");
} catch (IllegalBlockSizeException e) {
throw new Exception("密文長度非法");
} catch (BadPaddingException e) {
throw new Exception("密文數(shù)據(jù)已損壞");
}
}
public static PublicKey getPublicKey(byte[] keyBytes) throws NoSuchAlgorithmException,
InvalidKeySpecException
{
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
PublicKey publicKey = keyFactory.generatePublic(keySpec);
return publicKey;
}
public static PrivateKey getPrivateKey(byte[] keyBytes) throws NoSuchAlgorithmException,
InvalidKeySpecException
{
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
return privateKey;
}
public static PublicKey loadPublicKey(String publicKeyStr) throws Exception
{
try
{
byte[] buffer = Base64Utils.decode(publicKeyStr);
KeyFactory keyFactory = KeyFactory.getInstance(RSA, new BouncyCastleProvider());
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
return (RSAPublicKey) keyFactory.generatePublic(keySpec);
} catch (NoSuchAlgorithmException e)
{
throw new Exception("not this suanfa");
} catch (InvalidKeySpecException e)
{
throw new Exception("invalid public key");
} catch (NullPointerException e)
{
throw new Exception("public key is null");
}
}
public static PrivateKey loadPrivateKey(String privateKeyStr) throws Exception
{
try
{
byte[] buffer = Base64Utils.decode(privateKeyStr);
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer);
KeyFactory keyFactory = KeyFactory.getInstance(RSA, new BouncyCastleProvider());
return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
} catch (NoSuchAlgorithmException e)
{
throw new Exception("not this suanfa");
} catch (InvalidKeySpecException e)
{
throw new Exception("invalid private key");
} catch (NullPointerException e)
{
throw new Exception("private key is null");
}
}
}
</pre>
在此感謝網(wǎng)友的分享
1. JAVA與PHP之間的openssl交互加密
2. Java中使用OpenSSL生成的RSA公私鑰進(jìn)行數(shù)據(jù)加解密
