RSA密钥C#端转换成java密钥
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BASE64工具类
/*
* Copyright (C) 2010 The android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.UnsupportedEncodingException;
/**
* Utilities for encoding and decoding the Base64 representation of
* binary data. See RFCs <a
* href="http://www.ietf.org/rfc/rfc2045.txt">2045</a> and <a
* href="http://www.ietf.org/rfc/rfc3548.txt">3548</a>.
*/
public class Base64
/**
* Default values for encoder/decoder flags.
*/
public static final int DEFAULT = 0;
/**
* Encoder flag bit to omit the padding '=' characters at the end
* of the output (if any).
*/
public static final int NO_PADDING = 1;
/**
* Encoder flag bit to omit all line terminators (i.e., the output
* will be on one long line).
*/
public static final int NO_WRAP = 2;
/**
* Encoder flag bit to indicate lines should be terminated with a
* CRLF pair instead of just an LF. Has no effect if @code
* NO_WRAP is specified as well.
*/
public static final int CRLF = 4;
/**
* Encoder/decoder flag bit to indicate using the "URL and
* filename safe" variant of Base64 (see RFC 3548 section 4) where
* @code - and @code _ are used in place of @code + and
* @code /.
*/
public static final int URL_SAFE = 8;
/**
* Flag to pass to @link to indicate that it
* should not close the output stream it is wrapping when it
* itself is closed.
*/
public static final int NO_CLOSE = 16;
// --------------------------------------------------------
// shared code
// --------------------------------------------------------
/* package */ static abstract class Coder
public byte[] output;
public int op;
/**
* Encode/decode another block of input data. this.output is
* provided by the caller, and must be big enough to hold all
* the coded data. On exit, this.opwill be set to the length
* of the coded data.
*
* @param finish true if this is the final call to process for
* this object. Will finalize the coder state and
* include any final bytes in the output.
*
* @return true if the input so far is good; false if some
* error has been detected in the input stream..
*/
public abstract boolean process(byte[] input, int offset, int len, boolean finish);
/**
* @return the maximum number of bytes a call to process()
* could produce for the given number of input bytes. This may
* be an overestimate.
*/
public abstract int maxOutputSize(int len);
// --------------------------------------------------------
// decoding
// --------------------------------------------------------
/**
* Decode the Base64-encoded data in input and return the data in
* a new byte array.
*
* <p>The padding '=' characters at the end are considered optional, but
* if any are present, there must be the correct number of them.
*
* @param str the input String to decode, which is converted to
* bytes using the default charset
* @param flags controls certain features of the decoded output.
* Pass @code DEFAULT to decode standard Base64.
*
* @throws IllegalArgumentException if the input contains
* incorrect padding
*/
public static byte[] decode(String str, int flags)
return decode(str.getBytes(), flags);
/**
* Decode the Base64-encoded data in input and return the data in
* a new byte array.
*
* <p>The padding '=' characters at the end are considered optional, but
* if any are present, there must be the correct number of them.
*
* @param input the input array to decode
* @param flags controls certain features of the decoded output.
* Pass @code DEFAULT to decode standard Base64.
*
* @throws IllegalArgumentException if the input contains
* incorrect padding
*/
public static byte[] decode(byte[] input, int flags)
return decode(input, 0, input.length, flags);
/**
* Decode the Base64-encoded data in input and return the data in
* a new byte array.
*
* <p>The padding '=' characters at the end are considered optional, but
* if any are present, there must be the correct number of them.
*
* @param input the data to decode
* @param offset the position within the input array at which to start
* @param len the number of bytes of input to decode
* @param flags controls certain features of the decoded output.
* Pass @code DEFAULT to decode standard Base64.
*
* @throws IllegalArgumentException if the input contains
* incorrect padding
*/
public static byte[] decode(byte[] input, int offset, int len, int flags)
// Allocate space for the most data the input could represent.
// (It could contain less if it contains whitespace, etc.)
Decoder decoder = new Decoder(flags, new byte[len*3/4]);
if (!decoder.process(input, offset, len, true))
throw new IllegalArgumentException("bad base-64");
// Maybe we got lucky and allocated exactly enough output space.
if (decoder.op == decoder.output.length)
return decoder.output;
// Need to shorten the array, so allocate a new one of the
// right size and copy.
byte[] temp = new byte[decoder.op];
System.arraycopy(decoder.output, 0, temp, 0, decoder.op);
return temp;
/* package */ static class Decoder extends Coder
/**
* Lookup table for turning bytes into their position in the
* Base64 alphabet.
*/
private static final int DECODE[] =
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -2, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
;
/**
* Decode lookup table for the "web safe" variant (RFC 3548
* sec. 4) where - and _ replace + and /.
*/
private static final int DECODE_WEBSAFE[] =
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1,
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -2, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, 63,
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
;
/** Non-data values in the DECODE arrays. */
private static final int SKIP = -1;
private static final int EQUALS = -2;
/**
* States 0-3 are reading through the next input tuple.
* State 4 is having read one '=' and expecting exactly
* one more.
* State 5 is expecting no more data or padding characters
* in the input.
* State 6 is the error state; an error has been detected
* in the input and no future input can "fix" it.
*/
private int state; // state number (0 to 6)
private int value;
final private int[] alphabet;
public Decoder(int flags, byte[] output)
this.output = output;
alphabet = ((flags & URL_SAFE) == 0) ? DECODE : DECODE_WEBSAFE;
state = 0;
value = 0;
/**
* @return an overestimate for the number of bytes @code
* len bytes could decode to.
*/
public int maxOutputSize(int len)
return len * 3/4 + 10;
/**
* Decode another block of input data.
*
* @return true if the state machine is still healthy. false if
* bad base-64 data has been detected in the input stream.
*/
public boolean process(byte[] input, int offset, int len, boolean finish)
if (this.state == 6) return false;
int p = offset;
len += offset;
// Using local variables makes the decoder about 12%
// faster than if we manipulate the member variables in
// the loop. (Even alphabet makes a measurable
// difference, which is somewhat surprising to me since
// the member variable is final.)
int state = this.state;
int value = this.value;
int op = 0;
final byte[] output = this.output;
final int[] alphabet = this.alphabet;
while (p < len)
// Try the fast path: we're starting a new tuple and the
// next four bytes of the input stream are all data
// bytes. This corresponds to going through states
// 0-1-2-3-0. We expect to use this method for most of
// the data.
//
// If any of the next four bytes of input are non-data
// (whitespace, etc.), value will end up negative. (All
// the non-data values in decode are small negative
// numbers, so shifting any of them up and or'ing them
// together will result in a value with its top bit set.)
//
// You can remove this whole block and the output should
// be the same, just slower.
if (state == 0)
while (p+4 <= len &&
(value = ((alphabet[input[p] & 0xff] << 18) |
(alphabet[input[p+1] & 0xff] << 12) |
(alphabet[input[p+2] & 0xff] << 6) |
(alphabet[input[p+3] & 0xff]))) >= 0)
output[op+2] = (byte) value;
output[op+1] = (byte) (value >> 8);
output[op] = (byte) (value >> 16);
op += 3;
p += 4;
if (p >= len) break;
// The fast path isn't available -- either we've read a
// partial tuple, or the next four input bytes aren't all
// data, or whatever. Fall back to the slower state
// machine implementation.
int d = alphabet[input[p++] & 0xff];
switch (state)
case 0:
if (d >= 0)
value = d;
++state;
else if (d != SKIP)
this.state = 6;
return false;
break;
case 1:
if (d >= 0)
value = (value << 6) | d;
++state;
else if (d != SKIP)
this.state = 6;
return false;
break;
case 2:
if (d >= 0)
value = (value << 6) | d;
++state;
else if (d == EQUALS)
// Emit the last (partial) output tuple;
// expect exactly one more padding character.
output[op++] = (byte) (value >> 4);
state = 4;
else if (d != SKIP)
this.state = 6;
return false;
break;
case 3:
if (d >= 0)
// Emit the output triple and return to state 0.
value = (value << 6) | d;
output[op+2] = (byte) value;
output[op+1] = (byte) (value >> 8);
output[op] = (byte) (value >> 16);
op += 3;
state = 0;
else if (d == EQUALS)
// Emit the last (partial) output tuple;
// expect no further data or padding characters.
output[op+1] = (byte) (value >> 2);
output[op] = (byte) (value >> 10);
op += 2;
state = 5;
else if (d != SKIP)
this.state = 6;
return false;
break;
case 4:
if (d == EQUALS)
++state;
else if (d != SKIP)
this.state = 6;
return false;
break;
case 5:
if (d != SKIP)
this.state = 6;
return false;
break;
if (!finish)
// We're out of input, but a future call could provide
// more.
this.state = state;
this.value = value;
this.op = op;
return true;
// Done reading input. Now figure out where we are left in
// the state machine and finish up.
switch (state)
case 0:
// Output length is a multiple of three. Fine.
break;
case 1:
// Read one extra input byte, which isn't enough to
// make another output byte. Illegal.
this.state = 6;
return false;
case 2:
// Read two extra input bytes, enough to emit 1 more
// output byte. Fine.
output[op++] = (byte) (value >> 4);
break;
case 3:
// Read three extra input bytes, enough to emit 2 more
// output bytes. Fine.
output[op++] = (byte) (value >> 10);
output[op++] = (byte) (value >> 2);
break;
case 4:
// Read one padding '=' when we expected 2. Illegal.
this.state = 6;
return false;
case 5:
// Read all the padding '='s we expected and no more.
// Fine.
break;
this.state = state;
this.op = op;
return true;
// --------------------------------------------------------
// encoding
// --------------------------------------------------------
/**
* Base64-encode the given data and return a newly allocated
* String with the result.
*
* @param input the data to encode
* @param flags controls certain features of the encoded output.
* Passing @code DEFAULT results in output that
* adheres to RFC 2045.
*/
public static String encodeToString(byte[] input, int flags)
try
return new String(encode(input, flags), "US-ASCII");
catch (UnsupportedEncodingException e)
// US-ASCII is guaranteed to be available.
throw new AssertionError(e);
/**
* Base64-encode the given data and return a newly allocated
* String with the result.
*
* @param input the data to encode
* @param offset the position within the input array at which to
* start
* @param len the number of bytes of input to encode
* @param flags controls certain features of the encoded output.
* Passing @code DEFAULT results in output that
* adheres to RFC 2045.
*/
public static String encodeToString(byte[] input, int offset, int len, int flags)
try
return new String(encode(input, offset, len, flags), "US-ASCII");
catch (UnsupportedEncodingException e)
// US-ASCII is guaranteed to be available.
throw new AssertionError(e);
/**
* Base64-encode the given data and return a newly allocated
* byte[] with the result.
*
* @param input the data to encode
* @param flags controls certain features of the encoded output.
* Passing @code DEFAULT results in output that
* adheres to RFC 2045.
*/
public static byte[] encode(byte[] input, int flags)
return encode(input, 0, input.length, flags);
/**
* Base64-encode the given data and return a newly allocated
* byte[] with the result.
*
* @param input the data to encode
* @param offset the position within the input array at which to
* start
* @param len the number of bytes of input to encode
* @param flags controls certain features of the encoded output.
* Passing @code DEFAULT results in output that
* adheres to RFC 2045.
*/
public static byte[] encode(byte[] input, int offset, int len, int flags)
Encoder encoder = new Encoder(flags, null);
// Compute the exact length of the array we will produce.
int output_len = len / 3 * 4;
// Account for the tail of the data and the padding bytes, if any.
if (encoder.do_padding)
if (len % 3 > 0)
output_len += 4;
else
switch (len % 3)
case 0: break;
case 1: output_len += 2; break;
case 2: output_len += 3; break;
// Account for the newlines, if any.
if (encoder.do_newline && len > 0)
output_len += (((len-1) / (3 * Encoder.LINE_GROUPS)) + 1) *
(encoder.do_cr ? 2 : 1);
encoder.output = new byte[output_len];
encoder.process(input, offset, len, true);
assert encoder.op == output_len;
return encoder.output;
/* package */ static class Encoder extends Coder
/**
* Emit a new line every this many output tuples. Corresponds to
* a 76-character line length (the maximum allowable according to
* <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>).
*/
public static final int LINE_GROUPS = 19;
/**
* Lookup table for turning Base64 alphabet positions (6 bits)
* into output bytes.
*/
private static final byte ENCODE[] =
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/',
;
/**
* Lookup table for turning Base64 alphabet positions (6 bits)
* into output bytes.
*/
private static final byte ENCODE_WEBSAFE[] =
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '-', '_',
;
final private byte[] tail;
/* package */ int tailLen;
private int count;
final public boolean do_padding;
final public boolean do_newline;
final public boolean do_cr;
final private byte[] alphabet;
public Encoder(int flags, byte[] output)
this.output = output;
do_padding = (flags & NO_PADDING) == 0;
do_newline = (flags & NO_WRAP) == 0;
do_cr = (flags & CRLF) != 0;
alphabet = ((flags & URL_SAFE) == 0) ? ENCODE : ENCODE_WEBSAFE;
tail = new byte[2];
tailLen = 0;
count = do_newline ? LINE_GROUPS : -1;
/**
* @return an overestimate for the number of bytes @code
* len bytes could encode to.
*/
public int maxOutputSize(int len)
return len * 8/5 + 10;
public boolean process(byte[] input, int offset, int len, boolean finish)
// Using local variables makes the encoder about 9% faster.
final byte[] alphabet = this.alphabet;
final byte[] output = this.output;
int op = 0;
int count = this.count;
int p = offset;
len += offset;
int v = -1;
// First we need to concatenate the tail of the previous call
// with any input bytes available now and see if we can empty
// the tail.
switch (tailLen)
case 0:
// There was no tail.
break;
case 1:
if (p+2 <= len)
// A 1-byte tail with at least 2 bytes of
// input available now.
v = ((tail[0] & 0xff) << 16) |
((input[p++] & 0xff) << 8) |
(input[p++] & 0xff);
tailLen = 0;
;
break;
case 2:
if (p+1 <= len)
// A 2-byte tail with at least 1 byte of input.
v = ((tail[0] & 0xff) << 16) |
((tail[1] & 0xff) << 8) |
(input[p++] & 0xff);
tailLen = 0;
break;
if (v != -1)
output[op++] = alphabet[(v >> 18) & 0x3f];
output[op++] = alphabet[(v >> 12) & 0x3f];
output[op++] = alphabet[(v >> 6) & 0x3f];
output[op++] = alphabet[v & 0x3f];
if (--count == 0)
if (do_cr) output[op++] = '\\r';
output[op++] = '\\n';
count = LINE_GROUPS;
// At this point either there is no tail, or there are fewer
// than 3 bytes of input available.
// The main loop, turning 3 input bytes into 4 output bytes on
// each iteration.
while (p+3 <= len)
v = ((input[p] & 0xff) << 16) |
((input[p+1] & 0xff) << 8) |
(input[p+2] & 0xff);
output[op] = alphabet[(v >> 18) & 0x3f];
output[op+1] = alphabet[(v >> 12) & 0x3f];
output[op+2] = alphabet[(v >> 6) & 0x3f];
output[op+3] = alphabet[v & 0x3f];
p += 3;
op += 4;
if (--count == 0)
if (do_cr) output[op++] = '\\r';
output[op++] = '\\n';
count = LINE_GROUPS;
if (finish)
// Finish up the tail of the input. Note that we need to
// consume any bytes in tail before any bytes
// remaining in input; there should be at most two bytes
// total.
if (p-tailLen == len-1)
int t = 0;
v = ((tailLen > 0 ? tail[t++] : input[p++]) & 0xff) << 4;
tailLen -= t;
output[op++] = alphabet[(v >> 6) & 0x3f];
output[op++] = alphabet[v & 0x3f];
if (do_padding)
output[op++] = '=';
output[op++] = '=';
if (do_newline)
if (do_cr) output[op++] = '\\r';
output[op++] = '\\n';
else if (p-tailLen == len-2)
int t = 0;
v = (((tailLen > 1 ? tail[t++] : input[p++]) & 0xff) << 10) |
(((tailLen > 0 ? tail[t++] : input[p++]) & 0xff) << 2);
tailLen -= t;
output[op++] = alphabet[(v >> 12) & 0x3f];
output[op++] = alphabet[(v >> 6) & 0x3f];
output[op++] = alphabet[v & 0x3f];
if (do_padding)
output[op++] = '=';
if (do_newline)
if (do_cr) output[op++] = '\\r';
output[op++] = '\\n';
else if (do_newline && op > 0 && count != LINE_GROUPS)
if (do_cr) output[op++] = '\\r';
output[op++] = '\\n';
assert tailLen == 0;
assert p == len;
else
// Save the leftovers in tail to be consumed on the next
// call to encodeInternal.
if (p == len-1)
tail[tailLen++] = input[p];
else if (p == len-2)
tail[tailLen++] = input[p];
tail[tailLen++] = input[p+1];
this.op = op;
this.count = count;
return true;
//@UnsupportedAppUsage
private Base64() // don't instantiate
工具类
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.lang.reflect.Method;
import java.math.BigInteger;
import java.nio.charset.StandardCharsets;
import java.security.Key;
import java.security.KeyFactory;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.RSAPrivateCrtKeySpec;
import java.security.spec.RSAPublicKeySpec;
import java.security.spec.X509EncodedKeySpec;
import javax.crypto.Cipher;
public class RSAHelper
private static final String RSA = "RSA"; // RSA/ECB/PKCS1Padding
private static final String CLIPRSA = "RSA/ECB/PKCS1Padding";
private static final String PUBLIC_KEY = "<RSAKeyValue><Modulus>XXXXXXXXXXXXXXXXXXXXhs7KmHU8IoGJNW532+1xGqpbJbBxJBDu7KHAhfaNzEWv5xDf8bZIk7eBCBX92l7lyzf8IlniwVBwAHl2ftT+1Zvk5MmDQFeEaLfgHcydHVYK0z1oKzbcraO9/6/5v15fNRdHIiT2a/LjjBQusEMTXz8=</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>";
public static String getMiddle(String xml, String start, String end)
xml = xml.replaceAll("\\r", "").replaceAll("\\n", "");
if (xml.contains(start) && xml.contains(end))
return getMiddle(xml.substring(xml.indexOf(start) + start.length(), xml.lastIndexOf(end)), start, end);
else
return xml;
/**
* 读取密钥信息
*
* @param in
* @return
* @throws IOException
*/
public static String readKey(InputStream in) throws IOException
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String readLine = null;
StringBuilder sb = new StringBuilder();
while ((readLine = br.readLine()) != null)
if (readLine.charAt(0) == '-')
continue;
else
sb.append(readLine);
sb.append("");
return sb.toString();
/**
* 从文件中输入流中加载公钥 ,android 可以将公钥放在assets目录
*
* @param in
* @return
* @throws Exception
*/
public static PublicKey getPublicKey(InputStream in) throws Exception
try
return getPublicKey(readKey(in));
catch (IOException e)
throw new Exception("公钥数据流读取错误");
catch (NullPointerException e)
throw new Exception("公钥输入流为空");
/**
* 读取公钥信息
*
* @param key
* @return
* @throws Exception
*/
public static PublicKey getPublicKey(String key) throws Exception
try
byte[] keyBytes = Base64.decode(key, Base64.DEFAULT);
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
PublicKey publicKey = keyFactory.generatePublic(keySpec);
return publicKey;
catch (NoSuchAlgorithmException e)
throw new Exception("无此算法");
catch (InvalidKeySpecException e)
throw new Exception("私钥非法");
catch (NullPointerException e)
throw new Exception("私钥数据为空");
/*
* C#端公钥转换成java公钥
*/
public static PublicKey decodePublicKeyFromXml(String xml) throws Exception
xml = xml.replaceAll("\\r", "").replaceAll("\\n", "");
String moduluStr = getMiddle(xml, "<Modulus>", "</Modulus>");
BigInteger modulus = new BigInteger(1, Base64.decode(moduluStr, Base64.DEFAULT));
String exponentStr = getMiddle(xml, "<Exponent>", "</Exponent>");
BigInteger publicExponent = new BigInteger(1, Base64.decode(exponentStr, Base64.DEFAULT));
RSAPublicKeySpec rsaPubKey = new RSAPublicKeySpec(modulus, publicExponent);
KeyFactory keyf;
try
keyf = KeyFactory.getInstance(RSA);
return keyf.generatePublic(rsaPubKey);
catch (Exception e)
return null;
/*
* C#端私钥转换成java私钥
*/
public static PrivateKey decodePrivateKeyFromXml(String xml)
xml = xml.replaceAll("\\r", "").replaceAll("\\n", "");
String str = getMiddle(xml, "<Modulus>", "</Modulus>");
BigInteger modulus = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
str = getMiddle(xml, "<Exponent>", "</Exponent>");
BigInteger publicExponent = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
str = getMiddle(xml, "<D>", "</D>");
BigInteger privateExponent = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
str = getMiddle(xml, "<P>", "</P>");
BigInteger primeP = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
str = getMiddle(xml, "<Q>", "</Q>");
BigInteger primeQ = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
str = getMiddle(xml, "<DP>", "</DP>");
BigInteger primeExponentP = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
str = getMiddle(xml, "<DQ>", "</DQ>");
BigInteger primeExponentQ = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
str = getMiddle(xml, "<InverseQ>", "</InverseQ>");
BigInteger crtCoefficient = new BigInteger(1, Base64.decode(str, Base64.DEFAULT));
RSAPrivateCrtKeySpec rsaPriKey = new RSAPrivateCrtKeySpec(modulus, publicExponent, privateExponent, primeP,
primeQ, primeExponentP, primeExponentQ, crtCoefficient);
KeyFactory keyf;
try
keyf = KeyFactory.getInstance(RSA);
return keyf.generatePrivate(rsaPriKey);
catch (Exception e)
return null;
/**
* 从文件中输入流中加载私钥 ,android 可以将私钥放在assets目录
*
* @param in
* @return
* @throws Exception
*/
public static PrivateKey getPrivateKey(InputStream in) throws Exception
try
return getPrivateKey(readKey(in));
catch (IOException e)
throw new Exception("私钥数据读取错误");
catch (NullPointerException e)
throw new Exception("私钥输入流为空");
/**
* 读取私钥信息
*
* @param key
* @return
* @throws Exception
*/
public static PrivateKey getPrivateKey(String key) throws Exception
try
byte[] keyBytes = Base64.decode(key, Base64.DEFAULT);
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = KeyFactory.getInstance(RSA);
PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
return privateKey;
catch (NoSuchAlgorithmException e)
throw new Exception("无此算法");
catch (InvalidKeySpecException e)
throw new Exception("私钥非法");
catch (NullPointerException e)
throw new Exception("私钥数据为空");
/**
* 读取Key的信息
*
* @param key
* @return
* @throws Exception
*/
public static String getKeyString(Key key) throws Exception
byte[] keyBytes = key.getEncoded();
String s = Base64.encodeToString(keyBytes, Base64.DEFAULT);
return s;
/**
* RSA加密
*
* @param plainText
* 明文
* @return
* @throws Exception
*/
public static String encryptData(String plainText) throws Exception
PublicKey key = decodePublicKeyFromXml(PUBLIC_KEY);
// 加解密类
Cipher cipher = Cipher.getInstance(CLIPRSA);
// 加密
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] enBytes = cipher.doFinal(plainText.getBytes(StandardCharsets.UTF_8));
return Base64.encodeToString(enBytes, Base64.DEFAULT);
/**
* RSA 解密
*
* @param enBytes
* 加密数据
* @return
* @throws Exception
*/
public static byte[] decryptData(byte[] enBytes, PrivateKey key) throws Exception
// 加解密类
Cipher cipher = Cipher.getInstance(CLIPRSA);
// 解密
byte[] deBytes = null;
try
cipher.init(Cipher.DECRYPT_MODE, key);
deBytes = cipher.doFinal(enBytes);
catch (Exception e)
e.printStackTrace();
return deBytes;
/**
* RSA 解密
*
* @param encodedStr
* 加密数据
* @return
* @throws Exception
*/
public static String decryptData(String encodedStr,String rsa_private_key) throws Exception
PrivateKey privateKey = RSAHelper.decodePrivateKeyFromXml(rsa_private_key);
byte[] deBytes = Base64.decode(encodedStr, Base64.DEFAULT);
// 加解密类
Cipher cipher = Cipher.getInstance(CLIPRSA);
// 解密
try
cipher.init(Cipher.DECRYPT_MODE, privateKey);
deBytes = cipher.doFinal(deBytes);
catch (Exception e)
e.printStackTrace();
return new String(deBytes);
public static String encodeBase64(byte[] input) throws Exception
Class clazz = Class.forName("com.sun.org.apache.xerces.internal.impl.dv.util.Base64");
Method mainMethod = clazz.getMethod("encode", byte[].class);
mainMethod.setAccessible(true);
Object retObj = mainMethod.invoke(null, new Object[] input );
return (String) retObj;
public static byte[] decodeBase64(String input) throws Exception
Class clazz = Class.forName("com.sun.org.apache.xerces.internal.impl.dv.util.Base64");
Method mainMethod = clazz.getMethod("decode", String.class);
mainMethod.setAccessible(true);
Object retObj = mainMethod.invoke(null, input);
return (byte[]) retObj;
public static void main(String[] args) throws Exception
String enBytes = encryptData("2020-12-18 09:23:00");
System.out.println(enBytes);
调用
public static void main(String[] args) throws Exception
String enBytes = encryptData("2020-12-18 09:23:00");
System.out.println(enBytes);
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