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The Bouncy Castle Java API for handling the OpenPGP protocol. This jar contains the OpenPGP API for JDK 1.5 to JDK 1.7. The APIs can be used in conjunction with a JCE/JCA provider such as the one provided with the Bouncy Castle Cryptography APIs.
package org.bouncycastle.bcpg;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.Hashtable;
import org.bouncycastle.util.Strings;
/**
* Output stream that writes data in ASCII Armored format.
*
* Note 1: close() needs to be called on an ArmoredOutputStream to write the final checksum. flush() will not do this as
* other classes assume it is always fine to call flush() - it is not though if the checksum gets output.
* Note 2: as multiple PGP blobs are often written to the same stream, close() does not close the underlying stream.
*
*/
public class ArmoredOutputStream
extends OutputStream
{
public static final String VERSION_HDR = "Version";
private static final byte[] encodingTable =
{
(byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G',
(byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N',
(byte)'O', (byte)'P', (byte)'Q', (byte)'R', (byte)'S', (byte)'T', (byte)'U',
(byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z',
(byte)'a', (byte)'b', (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g',
(byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m', (byte)'n',
(byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u',
(byte)'v',
(byte)'w', (byte)'x', (byte)'y', (byte)'z',
(byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5', (byte)'6',
(byte)'7', (byte)'8', (byte)'9',
(byte)'+', (byte)'/'
};
/**
* encode the input data producing a base 64 encoded byte array.
*/
private void encode(
OutputStream out,
int[] data,
int len)
throws IOException
{
int d1, d2, d3;
switch (len)
{
case 0: /* nothing left to do */
break;
case 1:
d1 = data[0];
out.write(encodingTable[(d1 >>> 2) & 0x3f]);
out.write(encodingTable[(d1 << 4) & 0x3f]);
out.write('=');
out.write('=');
break;
case 2:
d1 = data[0];
d2 = data[1];
out.write(encodingTable[(d1 >>> 2) & 0x3f]);
out.write(encodingTable[((d1 << 4) | (d2 >>> 4)) & 0x3f]);
out.write(encodingTable[(d2 << 2) & 0x3f]);
out.write('=');
break;
case 3:
d1 = data[0];
d2 = data[1];
d3 = data[2];
out.write(encodingTable[(d1 >>> 2) & 0x3f]);
out.write(encodingTable[((d1 << 4) | (d2 >>> 4)) & 0x3f]);
out.write(encodingTable[((d2 << 2) | (d3 >>> 6)) & 0x3f]);
out.write(encodingTable[d3 & 0x3f]);
break;
default:
throw new IOException("unknown length in encode");
}
}
OutputStream out;
int[] buf = new int[3];
int bufPtr = 0;
CRC24 crc = new CRC24();
int chunkCount = 0;
int lastb;
boolean start = true;
boolean clearText = false;
boolean newLine = false;
String nl = Strings.lineSeparator();
String type;
String headerStart = "-----BEGIN PGP ";
String headerTail = "-----";
String footerStart = "-----END PGP ";
String footerTail = "-----";
String version = "BCPG v1.64";
Hashtable headers = new Hashtable();
/**
* Constructs an armored output stream with {@link #resetHeaders() default headers}.
*
* @param out the OutputStream to wrap.
*/
public ArmoredOutputStream(
OutputStream out)
{
this.out = out;
if (nl == null)
{
nl = "\r\n";
}
headers.put(VERSION_HDR, version);
}
/**
* Constructs an armored output stream with default and custom headers.
*
* @param out the OutputStream to wrap.
* @param headers additional headers that add to or override the {@link #resetHeaders() default
* headers}.
*/
public ArmoredOutputStream(
OutputStream out,
Hashtable headers)
{
this(out);
Enumeration e = headers.keys();
while (e.hasMoreElements())
{
Object key = e.nextElement();
this.headers.put(key, headers.get(key));
}
}
/**
* Set an additional header entry. A null value will clear the entry for name.
*
* @param name the name of the header entry.
* @param value the value of the header entry.
*/
public void setHeader(
String name,
String value)
{
if (value == null)
{
this.headers.remove(name);
}
else
{
this.headers.put(name, value);
}
}
/**
* Reset the headers to only contain a Version string (if one is present)
*/
public void resetHeaders()
{
String version = (String)headers.get(VERSION_HDR);
headers.clear();
if (version != null)
{
headers.put(VERSION_HDR, version);
}
}
/**
* Start a clear text signed message.
* @param hashAlgorithm
*/
public void beginClearText(
int hashAlgorithm)
throws IOException
{
String hash;
switch (hashAlgorithm)
{
case HashAlgorithmTags.SHA1:
hash = "SHA1";
break;
case HashAlgorithmTags.SHA256:
hash = "SHA256";
break;
case HashAlgorithmTags.SHA384:
hash = "SHA384";
break;
case HashAlgorithmTags.SHA512:
hash = "SHA512";
break;
case HashAlgorithmTags.MD2:
hash = "MD2";
break;
case HashAlgorithmTags.MD5:
hash = "MD5";
break;
case HashAlgorithmTags.RIPEMD160:
hash = "RIPEMD160";
break;
default:
throw new IOException("unknown hash algorithm tag in beginClearText: " + hashAlgorithm);
}
String armorHdr = "-----BEGIN PGP SIGNED MESSAGE-----" + nl;
String hdrs = "Hash: " + hash + nl + nl;
for (int i = 0; i != armorHdr.length(); i++)
{
out.write(armorHdr.charAt(i));
}
for (int i = 0; i != hdrs.length(); i++)
{
out.write(hdrs.charAt(i));
}
clearText = true;
newLine = true;
lastb = 0;
}
public void endClearText()
{
clearText = false;
}
private void writeHeaderEntry(
String name,
String value)
throws IOException
{
for (int i = 0; i != name.length(); i++)
{
out.write(name.charAt(i));
}
out.write(':');
out.write(' ');
for (int i = 0; i != value.length(); i++)
{
out.write(value.charAt(i));
}
for (int i = 0; i != nl.length(); i++)
{
out.write(nl.charAt(i));
}
}
public void write(
int b)
throws IOException
{
if (clearText)
{
out.write(b);
if (newLine)
{
if (!(b == '\n' && lastb == '\r'))
{
newLine = false;
}
if (b == '-')
{
out.write(' ');
out.write('-'); // dash escape
}
}
if (b == '\r' || (b == '\n' && lastb != '\r'))
{
newLine = true;
}
lastb = b;
return;
}
if (start)
{
boolean newPacket = (b & 0x40) != 0;
int tag = 0;
if (newPacket)
{
tag = b & 0x3f;
}
else
{
tag = (b & 0x3f) >> 2;
}
switch (tag)
{
case PacketTags.PUBLIC_KEY:
type = "PUBLIC KEY BLOCK";
break;
case PacketTags.SECRET_KEY:
type = "PRIVATE KEY BLOCK";
break;
case PacketTags.SIGNATURE:
type = "SIGNATURE";
break;
default:
type = "MESSAGE";
}
for (int i = 0; i != headerStart.length(); i++)
{
out.write(headerStart.charAt(i));
}
for (int i = 0; i != type.length(); i++)
{
out.write(type.charAt(i));
}
for (int i = 0; i != headerTail.length(); i++)
{
out.write(headerTail.charAt(i));
}
for (int i = 0; i != nl.length(); i++)
{
out.write(nl.charAt(i));
}
if (headers.containsKey(VERSION_HDR))
{
writeHeaderEntry(VERSION_HDR, (String)headers.get(VERSION_HDR));
}
Enumeration e = headers.keys();
while (e.hasMoreElements())
{
String key = (String)e.nextElement();
if (!key.equals(VERSION_HDR))
{
writeHeaderEntry(key, (String)headers.get(key));
}
}
for (int i = 0; i != nl.length(); i++)
{
out.write(nl.charAt(i));
}
start = false;
}
if (bufPtr == 3)
{
encode(out, buf, bufPtr);
bufPtr = 0;
if ((++chunkCount & 0xf) == 0)
{
for (int i = 0; i != nl.length(); i++)
{
out.write(nl.charAt(i));
}
}
}
crc.update(b);
buf[bufPtr++] = b & 0xff;
}
public void flush()
throws IOException
{
}
/**
* Note: close() does not close the underlying stream. So it is possible to write
* multiple objects using armoring to a single stream.
*/
public void close()
throws IOException
{
if (type != null)
{
encode(out, buf, bufPtr);
for (int i = 0; i != nl.length(); i++)
{
out.write(nl.charAt(i));
}
out.write('=');
int crcV = crc.getValue();
buf[0] = ((crcV >> 16) & 0xff);
buf[1] = ((crcV >> 8) & 0xff);
buf[2] = (crcV & 0xff);
encode(out, buf, 3);
for (int i = 0; i != nl.length(); i++)
{
out.write(nl.charAt(i));
}
for (int i = 0; i != footerStart.length(); i++)
{
out.write(footerStart.charAt(i));
}
for (int i = 0; i != type.length(); i++)
{
out.write(type.charAt(i));
}
for (int i = 0; i != footerTail.length(); i++)
{
out.write(footerTail.charAt(i));
}
for (int i = 0; i != nl.length(); i++)
{
out.write(nl.charAt(i));
}
out.flush();
type = null;
start = true;
}
}
}