edu.uiuc.ncsa.security.util.crypto.PEMFormatUtil Maven / Gradle / Ivy
package edu.uiuc.ncsa.security.util.crypto;
import org.apache.commons.codec.binary.Base64;
import java.io.*;
/**
* This does the grunt work of formatting keys and cert requests.
* Created by Jeff Gaynor
* on Jun 7, 2011 at 11:37:35 AM
*/
public class PEMFormatUtil {
/**
* Strip off the head and tail of a PEM encoded string. This just returns the body.
*
* @param pem
* @param head
* @param tail
* @return
*/
public static String getBody(String pem, String head, String tail) {
// Be forgiving of trailing whitespace and line feeds
pem = pem.trim();
String linefeed = "\n"; // Good old OS/2. Oh, um, and Unix too...
if (pem.endsWith("\r")) {
// older Macs
linefeed = "\r";
} else if (pem.endsWith("\r\n")) {
// Some Windows systems
linefeed = "\r\n";
}
while (pem.endsWith(linefeed)) {
pem = pem.substring(0, pem.length() - linefeed.length());
}
if (!pem.startsWith(head) || !pem.endsWith(tail)) {
throw new IllegalArgumentException("Error: unrecognized format. The PEM encoding must start with " + head + " and end with " + tail);
}
return pem.substring(head.length() + 1, pem.length() - (tail.length() + 1));
}
/**
* Gets the body bytes, i.e., what is between the head and tail (which you must supply) of the pem.
* @param pem
* @param head
* @param tail
* @return
*/
public static byte[] getBodyBytes(String pem, String head, String tail) {
return Base64.decodeBase64(getBody(pem, head, tail));
}
/**
* Roughly the inverse of (@link {@link PEMFormatUtil#getBodyBytes(String, String, String)},
* This will take any array of bytes, base 64 encode it and slap the head and tail around it.
* @param body
* @param head
* @param tail
* @return
*/
public static String delimitBody(byte[] body, String head, String tail) {
return delimitBody(bytesToChunkedString(body), head, tail);
}
/**
* Utility to delimit a string (usually base 4 encoded DER byte array) with specific
* head and tail. This checks that there are not extra carriage returns (which would invalidate
* the output).
*
* @param body
* @param head
* @param tail
* @return
*/
public static String delimitBody(String body, String head, String tail) {
StringWriter sw = new StringWriter();
delimitBody(body, head, tail, sw);
return sw.getBuffer().toString();
}
/**
* Same as {@link PEMFormatUtil#delimitBody(byte[], String, String)}, but send the result to
* the stream.
* @param body
* @param head
* @param tail
* @param outputStream
*/
public static void delimitBody(byte[] body, String head, String tail, OutputStream outputStream) {
delimitBody(bytesToChunkedString(body), head, tail, outputStream);
}
/**
* Fixes OAUTH-212: upgrade to version 1.10 of apache commons no longer chunks strings, so PEM format of
* all keys and certs are no longer readable by Open SSL, e.g.
* @param body
* @return
*/
public static String bytesToChunkedString(byte[] body){
byte[] out = Base64.encodeBase64Chunked(body);
String foo = new String(out);
return foo;
}
/**
* Same as {@link PEMFormatUtil#delimitBody(String, String, String)} but send the result to a {@link PrintWriter}.
* @param body
* @param head
* @param tail
* @param pw
*/
protected static void delimitBody(String body, String head, String tail, PrintWriter pw) {
pw.println(head);
String body2 = body.replaceAll("\r\n", "\n"); //commons library sticks return + linefeed no matter what, so strip it out.
if (body2.endsWith("\n")) {
pw.print(body2); //otherwise an extra linefeed occurs and the format is invalid.
} else {
pw.println(body2);
}
pw.print(tail);
pw.flush();
}
/**
* Same as {@link PEMFormatUtil#delimitBody(String, String, String)} but send output to a writer
* @param body
* @param head
* @param tail
* @param writer
*/
public static void delimitBody(String body, String head, String tail, Writer writer) {
delimitBody(body, head, tail, new PrintWriter(writer));
}
/**
* Same as {@link PEMFormatUtil#delimitBody(String, String, String)} but send output to a stream.
* @param body
* @param head
* @param tail
* @param outputStream
*/
public static void delimitBody(String body, String head, String tail, OutputStream outputStream) {
delimitBody(body, head, tail, new PrintWriter(outputStream));
}
/**
* Take a reader and stick its contents into a string. This is needed, e.g., to pass to the
* base64 decoder.
*
* @param f
* @return
* @throws IOException
*/
public static String readerToString(Reader f) throws IOException {
StringBuffer fileData = new StringBuffer(1000);
BufferedReader reader = new BufferedReader(f);
char[] buf = new char[1024];
int numRead = 0;
while ((numRead = reader.read(buf)) != -1) {
String readData = String.valueOf(buf, 0, numRead);
fileData.append(readData);
buf = new char[1024];
}
reader.close();
return fileData.toString();
}
}