/*
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* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
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package com.sun.mail.pop3;
import java.util.*;
import java.net.*;
import java.io.*;
import java.security.*;
import com.sun.mail.util.LineInputStream;
import com.sun.mail.util.SocketFetcher;
import com.sun.mail.util.PropUtil;
import javax.mail.util.SharedByteArrayInputStream;
class Response {
boolean ok = false; // true if "+OK"
String data = null; // rest of line after "+OK" or "-ERR"
InputStream bytes = null; // all the bytes from a multi-line response
}
/**
* This class provides a POP3 connection and implements
* the POP3 protocol requests.
*
* APOP support courtesy of "chamness".
*
* @author Bill Shannon
*/
class Protocol {
private Socket socket; // POP3 socket
private DataInputStream input; // input buf
private PrintWriter output; // output buf
private static final int POP3_PORT = 110; // standard POP3 port
private static final String CRLF = "\r\n";
private boolean debug = false;
private PrintStream out;
private String apopChallenge = null;
/**
* Open a connection to the POP3 server.
*/
Protocol(String host, int port, boolean debug, PrintStream out,
Properties props, String prefix, boolean isSSL)
throws IOException {
this.debug = debug;
this.out = out;
Response r;
boolean enableAPOP = PropUtil.getBooleanProperty(props,
prefix + ".apop.enable", false);
try {
if (port == -1)
port = POP3_PORT;
if (debug)
out.println("DEBUG POP3: connecting to host \"" + host +
"\", port " + port + ", isSSL " + isSSL);
socket = SocketFetcher.getSocket(host, port, props, prefix, isSSL);
input = new DataInputStream(
new BufferedInputStream(socket.getInputStream()));
output = new PrintWriter(
new BufferedWriter(
new OutputStreamWriter(socket.getOutputStream(),
"iso-8859-1")));
// should be US-ASCII, but not all JDK's support
r = simpleCommand(null);
} catch (IOException ioe) {
try {
socket.close();
} finally {
throw ioe;
}
}
if (!r.ok) {
try {
socket.close();
} finally {
throw new IOException("Connect failed");
}
}
if (enableAPOP) {
int challStart = r.data.indexOf('<'); // start of challenge
int challEnd = r.data.indexOf('>', challStart); // end of challenge
if (challStart != -1 && challEnd != -1)
apopChallenge = r.data.substring(challStart, challEnd + 1);
if (debug)
out.println("DEBUG POP3: APOP challenge: " + apopChallenge);
}
}
protected void finalize() throws Throwable {
super.finalize();
if (socket != null) { // Forgot to logout ?!
quit();
}
}
/**
* Login to the server, using the USER and PASS commands.
*/
synchronized String login(String user, String password)
throws IOException {
Response r;
String dpw = null;
if (apopChallenge != null)
dpw = getDigest(password);
if (apopChallenge != null && dpw != null) {
r = simpleCommand("APOP " + user + " " + dpw);
} else {
r = simpleCommand("USER " + user);
if (!r.ok)
return r.data != null ? r.data : "USER command failed";
r = simpleCommand("PASS " + password);
}
if (!r.ok)
return r.data != null ? r.data : "login failed";
return null;
}
/**
* Gets the APOP message digest.
* From RFC 1939:
*
* The 'digest' parameter is calculated by applying the MD5
* algorithm [RFC1321] to a string consisting of the timestamp
* (including angle-brackets) followed by a shared secret.
* The 'digest' parameter itself is a 16-octet value which is
* sent in hexadecimal format, using lower-case ASCII characters.
*
* @param password The APOP password
* @return The APOP digest or an empty string if an error occurs.
*/
private String getDigest(String password) {
String key = apopChallenge + password;
byte[] digest;
try {
MessageDigest md = MessageDigest.getInstance("MD5");
digest = md.digest(key.getBytes("iso-8859-1")); // XXX
} catch (NoSuchAlgorithmException nsae) {
return null;
} catch (UnsupportedEncodingException uee) {
return null;
}
return toHex(digest);
}
private static char[] digits = {
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
/**
* Convert a byte array to a string of hex digits representing the bytes.
*/
private static String toHex(byte[] bytes) {
char[] result = new char[bytes.length * 2];
for (int index = 0, i = 0; index < bytes.length; index++) {
int temp = bytes[index] & 0xFF;
result[i++] = digits[temp >> 4];
result[i++] = digits[temp & 0xF];
}
return new String(result);
}
/**
* Close down the connection, sending the QUIT command.
*/
synchronized boolean quit() throws IOException {
boolean ok = false;
try {
Response r = simpleCommand("QUIT");
ok = r.ok;
} finally {
try {
socket.close();
} finally {
socket = null;
input = null;
output = null;
}
}
return ok;
}
/**
* Return the total number of messages and mailbox size,
* using the STAT command.
*/
synchronized Status stat() throws IOException {
Response r = simpleCommand("STAT");
Status s = new Status();
if (r.ok && r.data != null) {
try {
StringTokenizer st = new StringTokenizer(r.data);
s.total = Integer.parseInt(st.nextToken());
s.size = Integer.parseInt(st.nextToken());
} catch (Exception e) {
}
}
return s;
}
/**
* Return the size of the message using the LIST command.
*/
synchronized int list(int msg) throws IOException {
Response r = simpleCommand("LIST " + msg);
int size = -1;
if (r.ok && r.data != null) {
try {
StringTokenizer st = new StringTokenizer(r.data);
st.nextToken(); // skip message number
size = Integer.parseInt(st.nextToken());
} catch (Exception e) {
}
}
return size;
}
/**
* Return the size of all messages using the LIST command.
*/
synchronized InputStream list() throws IOException {
Response r = multilineCommand("LIST", 128); // 128 == output size est
return r.bytes;
}
/**
* Retrieve the specified message.
* Given an estimate of the message's size we can be more efficient,
* preallocating the array and returning a SharedInputStream to allow
* us to share the array.
*/
synchronized InputStream retr(int msg, int size) throws IOException {
Response r = multilineCommand("RETR " + msg, size);
return r.bytes;
}
/**
* Return the message header and the first n lines of the message.
*/
synchronized InputStream top(int msg, int n) throws IOException {
Response r = multilineCommand("TOP " + msg + " " + n, 0);
return r.bytes;
}
/**
* Delete (permanently) the specified message.
*/
synchronized boolean dele(int msg) throws IOException {
Response r = simpleCommand("DELE " + msg);
return r.ok;
}
/**
* Return the UIDL string for the message.
*/
synchronized String uidl(int msg) throws IOException {
Response r = simpleCommand("UIDL " + msg);
if (!r.ok)
return null;
int i = r.data.indexOf(' ');
if (i > 0)
return r.data.substring(i + 1);
else
return null;
}
/**
* Return the UIDL strings for all messages.
* The UID for msg #N is returned in uids[N-1].
*/
synchronized boolean uidl(String[] uids) throws IOException {
Response r = multilineCommand("UIDL", 15 * uids.length);
if (!r.ok)
return false;
LineInputStream lis = new LineInputStream(r.bytes);
String line = null;
while ((line = lis.readLine()) != null) {
int i = line.indexOf(' ');
if (i < 1 || i >= line.length())
continue;
int n = Integer.parseInt(line.substring(0, i));
if (n > 0 && n <= uids.length)
uids[n - 1] = line.substring(i + 1);
}
return true;
}
/**
* Do a NOOP.
*/
synchronized boolean noop() throws IOException {
Response r = simpleCommand("NOOP");
return r.ok;
}
/**
* Do an RSET.
*/
synchronized boolean rset() throws IOException {
Response r = simpleCommand("RSET");
return r.ok;
}
/**
* Issue a simple POP3 command and return the response.
*/
private Response simpleCommand(String cmd) throws IOException {
if (socket == null)
throw new IOException("Folder is closed"); // XXX
String line = null;
try {
if (cmd != null) {
if (debug)
out.println("C: " + cmd);
cmd += CRLF;
output.print(cmd); // do it in one write
output.flush();
}
line = input.readLine(); // XXX - readLine is deprecated
} catch (InterruptedIOException iioex) {
/*
* If we get a timeout while using the socket, we have no idea
* what state the connection is in. The server could still be
* alive, but slow, and could still be sending data. The only
* safe way to recover is to drop the connection. Later use
* of the socket should get an EOFException.
*/
try {
socket.close();
} catch (IOException cex) { }
throw iioex;
}
if (line == null) {
if (debug)
out.println("S: EOF");
throw new EOFException("EOF on socket");
}
if (debug)
out.println("S: " + line);
Response r = new Response();
if (line.startsWith("+OK"))
r.ok = true;
else if (line.startsWith("-ERR"))
r.ok = false;
else
throw new IOException("Unexpected response: " + line);
int i;
if ((i = line.indexOf(' ')) >= 0)
r.data = line.substring(i + 1);
return r;
}
/**
* Issue a POP3 command that expects a multi-line response.
* <code>size</code> is an estimate of the response size.
*/
private Response multilineCommand(String cmd, int size) throws IOException {
Response r = simpleCommand(cmd);
if (!r.ok)
return (r);
SharedByteArrayOutputStream buf = new SharedByteArrayOutputStream(size);
int b, lastb = '\n';
try {
while ((b = input.read()) >= 0) {
if (lastb == '\n' && b == '.') {
if (debug)
out.write(b);
b = input.read();
if (b == '\r') {
if (debug)
out.write(b);
// end of response, consume LF as well
b = input.read();
if (debug)
out.write(b);
break;
}
}
buf.write(b);
if (debug)
out.write(b);
lastb = b;
}
} catch (InterruptedIOException iioex) {
/*
* As above in simpleCommand, close the socket to recover.
*/
try {
socket.close();
} catch (IOException cex) { }
throw iioex;
}
if (b < 0)
throw new EOFException("EOF on socket");
r.bytes = buf.toStream();
return r;
}
}
/**
* A ByteArrayOutputStream that allows us to share the byte array
* rather than copy it. Eventually could replace this with something
* that doesn't require a single contiguous byte array.
*/
class SharedByteArrayOutputStream extends ByteArrayOutputStream {
public SharedByteArrayOutputStream(int size) {
super(size);
}
public InputStream toStream() {
return new SharedByteArrayInputStream(buf, 0, count);
}
}