/*
* Autopsy Forensic Browser
*
* Copyright 2011-2014 Basis Technology Corp.
* Contact: carrier <at> sleuthkit <dot> org
*
* 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.
*/
package org.sleuthkit.autopsy.thunderbirdparser;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.CharConversionException;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.nio.charset.IllegalCharsetNameException;
import java.nio.charset.StandardCharsets;
import java.nio.charset.UnsupportedCharsetException;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.james.mime4j.dom.BinaryBody;
import org.apache.james.mime4j.dom.Body;
import org.apache.james.mime4j.dom.Entity;
import org.apache.james.mime4j.dom.Message;
import org.apache.james.mime4j.dom.Multipart;
import org.apache.james.mime4j.dom.TextBody;
import org.apache.james.mime4j.dom.address.AddressList;
import org.apache.james.mime4j.dom.address.Mailbox;
import org.apache.james.mime4j.dom.address.MailboxList;
import org.apache.james.mime4j.dom.field.ContentDispositionField;
import org.apache.james.mime4j.dom.field.ContentTypeField;
import org.apache.james.mime4j.mboxiterator.CharBufferWrapper;
import org.apache.james.mime4j.mboxiterator.MboxIterator;
import org.apache.james.mime4j.message.DefaultMessageBuilder;
import org.apache.james.mime4j.stream.MimeConfig;
import org.apache.tika.parser.txt.CharsetDetector;
import org.apache.tika.parser.txt.CharsetMatch;
import org.openide.util.NbBundle;
import org.sleuthkit.autopsy.ingest.IngestServices;
/**
* A parser that extracts information about email messages and attachments from
* a mbox file.
*
* @author jwallace
*/
class MboxParser {
private static final Logger logger = Logger.getLogger(MboxParser.class.getName());
private DefaultMessageBuilder messageBuilder;
private IngestServices services;
private StringBuilder errors;
/**
* The mime type string for html text.
*/
private static final String HTML_TYPE = "text/html"; //NON-NLS
/**
* The local path of the mbox file.
*/
private String localPath;
MboxParser(IngestServices services, String localPath) {
this.services = services;
this.localPath = localPath;
messageBuilder = new DefaultMessageBuilder();
MimeConfig config = MimeConfig.custom().setMaxLineLen(-1).build();
// disable line length checks.
messageBuilder.setMimeEntityConfig(config);
errors = new StringBuilder();
}
static boolean isValidMimeTypeMbox(byte[] buffer) {
return (new String(buffer)).startsWith("From "); //NON-NLS
}
/**
* Parse the mbox file and get the email messages.
* @param mboxFile
* @return a list of the email messages in the mbox file.
*/
List<EmailMessage> parse(File mboxFile) {
// Detect possible charsets
List<CharsetEncoder> encoders = getPossibleEncoders(mboxFile);
CharsetEncoder theEncoder = null;
Iterable<CharBufferWrapper> mboxIterator = null;
// Loop through the possible encoders and find the first one that works.
// That will usually be one of the first ones.
for (CharsetEncoder encoder : encoders) {
try {
mboxIterator = MboxIterator.fromFile(mboxFile).charset(encoder.charset()).build();
theEncoder = encoder;
break;
} catch (CharConversionException | UnsupportedCharsetException ex) {
// Not the right encoder
} catch (IllegalArgumentException ex) {
// Not the right encoder
} catch (IOException ex) {
logger.log(Level.WARNING, "couldn't find mbox file.", ex); //NON-NLS
addErrorMessage(NbBundle.getMessage(this.getClass(), "MboxParser.parse.errMsg.failedToReadFile"));
return new ArrayList<>();
}
}
// If no encoders work, post an error message and return.
if (mboxIterator == null || theEncoder == null) {
addErrorMessage(NbBundle.getMessage(this.getClass(), "MboxParser.parse.errMsg.couldntFindCharset"));
return new ArrayList<>();
}
List<EmailMessage> emails = new ArrayList<>();
long failCount = 0;
// Parse each message and extract an EmailMessage structure
for (CharBufferWrapper message : mboxIterator) {
try {
Message msg = messageBuilder.parseMessage(message.asInputStream(theEncoder.charset()));
emails.add(extractEmail(msg));
} catch (IOException ex) {
logger.log(Level.WARNING, "Failed to get message from mbox: {0}", ex.getMessage()); //NON-NLS
failCount++;
}
}
if (failCount > 0) {
addErrorMessage(
NbBundle.getMessage(this.getClass(), "MboxParser.parse.errMsg.failedToParseNMsgs", failCount));
}
return emails;
}
String getErrors() {
return errors.toString();
}
/**
* Use the information stored in the given mime4j message to populate an
* EmailMessage.
*
* @param msg
* @return
*/
private EmailMessage extractEmail(Message msg) {
EmailMessage email = new EmailMessage();
// Basic Info
email.setSender(getAddresses(msg.getFrom()));
email.setRecipients(getAddresses(msg.getTo()));
email.setBcc(getAddresses(msg.getBcc()));
email.setCc(getAddresses(msg.getCc()));
email.setSubject(msg.getSubject());
email.setSentDate(msg.getDate());
email.setLocalPath(localPath);
// Body
if (msg.isMultipart()) {
handleMultipart(email, (Multipart) msg.getBody());
} else {
handleTextBody(email, (TextBody) msg.getBody(), msg.getMimeType());
}
return email;
}
/**
* Handle a multipart mime message.
* Recursively calls handleMultipart if one of the body parts is another
* multipart. Otherwise, calls the correct method to extract information out
* of each part of the body.
*
* @param email
* @param multi
*/
private void handleMultipart(EmailMessage email, Multipart multi) {
for (Entity e : multi.getBodyParts()) {
if (e.isMultipart()) {
handleMultipart(email, (Multipart) e.getBody());
} else if (e.getDispositionType() != null
&& e.getDispositionType().equals(ContentDispositionField.DISPOSITION_TYPE_ATTACHMENT)) {
handleAttachment(email, e);
} else if (e.getMimeType().equals(HTML_TYPE) ||
e.getMimeType().equals(ContentTypeField.TYPE_TEXT_PLAIN)) {
handleTextBody(email, (TextBody) e.getBody(), e.getMimeType());
} else {
// Ignore other types.
}
}
}
/**
* Extract text out of a body part of the message.
*
* Handles text and html mime types. Throws away all other types. (only other
* example I've seen is text/calendar)
* @param email
* @param tb
* @param type The Mime type of the body.
*/
private void handleTextBody(EmailMessage email, TextBody tb, String type) {
BufferedReader r;
try {
r = new BufferedReader(tb.getReader());
StringBuilder bodyString = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
bodyString.append(line).append("\n");
}
switch (type) {
case ContentTypeField.TYPE_TEXT_PLAIN:
email.setTextBody(bodyString.toString());
break;
case HTML_TYPE:
email.setHtmlBody(bodyString.toString());
break;
default:
// Not interested in other text types.
break;
}
} catch (IOException ex) {
logger.log(Level.WARNING, "Error getting text body of mbox message", ex); //NON-NLS
}
}
/**
* Extract the attachment out of the given entity.
* Should only be called if e.getDispositionType() == "attachment"
* @param email
* @param e
*/
private void handleAttachment(EmailMessage email, Entity e) {
String outputDirPath = ThunderbirdMboxFileIngestModule.getModuleOutputPath() + File.separator;
String filename = e.getFilename();
// sanitize name. Had an attachment with a Japanese encoded path that
// invalid characters and attachment could not be saved.
filename = filename.replaceAll("\\?", "_");
filename = filename.replaceAll("<", "_");
filename = filename.replaceAll(">", "_");
filename = filename.replaceAll(":", "_");
filename = filename.replaceAll("\"", "_");
filename = filename.replaceAll("/", "_");
filename = filename.replaceAll("\\\\", "_");
filename = filename.replaceAll("|", "_");
filename = filename.replaceAll("\\*", "_");
// also had some crazy long names, so make random one if we get those.
// also from Japanese image that had encoded name
if (filename.length() > 64) {
filename = UUID.randomUUID().toString();
}
String uniqueFilename = filename + "-" + email.getSentDate();
String outPath = outputDirPath + uniqueFilename;
FileOutputStream fos;
BinaryBody bb;
try {
fos = new FileOutputStream(outPath);
} catch (FileNotFoundException ex) {
addErrorMessage(
NbBundle.getMessage(this.getClass(),
"MboxParser.handleAttch.errMsg.failedToCreateOnDisk", outPath));
logger.log(Level.INFO, "Failed to create file output stream for: " + outPath, ex); //NON-NLS
return;
}
try {
Body b = e.getBody();
if (b instanceof BinaryBody) {
bb = (BinaryBody) b;
bb.writeTo(fos);
} else {
// This could potentially be other types. Only seen this once.
}
} catch (IOException ex) {
logger.log(Level.INFO, "Failed to write mbox email attachment to disk.", ex); //NON-NLS
addErrorMessage(NbBundle.getMessage(this.getClass(), "MboxParser.handleAttch.failedWriteToDisk", filename));
return;
} finally {
try {
fos.close();
} catch (IOException ex) {
logger.log(Level.INFO, "Failed to close file output stream", ex); //NON-NLS
}
}
EmailMessage.Attachment attach = new EmailMessage.Attachment();
attach.setName(filename);
attach.setLocalPath(ThunderbirdMboxFileIngestModule.getRelModuleOutputPath()
+ File.separator + uniqueFilename);
attach.setSize(new File(outPath).length());
email.addAttachment(attach);
}
/**
* Get a String representation of the MailboxList (which is a list of email
* addresses).
* @param mailboxList
* @return
*/
private String getAddresses(MailboxList mailboxList) {
if (mailboxList == null) {
return "";
}
StringBuilder addresses = new StringBuilder();
for (Mailbox m : mailboxList) {
addresses.append(m.toString()).append("; ");
}
return addresses.toString();
}
/**
* Get a String representation of the AddressList (which is a list of email
* addresses).
* @param addressList
* @return
*/
private String getAddresses(AddressList addressList) {
return (addressList == null) ? "" : getAddresses(addressList.flatten());
}
/**
* Get a list of the possible encoders for the given mboxFile using Tika's
* CharsetDetector. At a minimum, returns the standard built in charsets.
* @param mboxFile
* @return
*/
private List<CharsetEncoder> getPossibleEncoders(File mboxFile) {
InputStream is;
List<CharsetEncoder> possibleEncoders = new ArrayList<>();
possibleEncoders.add(StandardCharsets.ISO_8859_1.newEncoder());
possibleEncoders.add(StandardCharsets.US_ASCII.newEncoder());
possibleEncoders.add(StandardCharsets.UTF_16.newEncoder());
possibleEncoders.add(StandardCharsets.UTF_16BE.newEncoder());
possibleEncoders.add(StandardCharsets.UTF_16LE.newEncoder());
possibleEncoders.add(StandardCharsets.UTF_8.newEncoder());
try {
is = new BufferedInputStream(new FileInputStream(mboxFile));
} catch (FileNotFoundException ex) {
logger.log(Level.WARNING, "Failed to find mbox file while detecting charset"); //NON-NLS
return possibleEncoders;
}
try {
CharsetDetector detector = new CharsetDetector();
detector.setText(is);
CharsetMatch[] matches = detector.detectAll();
for (CharsetMatch match : matches) {
try {
possibleEncoders.add(Charset.forName(match.getName()).newEncoder());
} catch (UnsupportedCharsetException | IllegalCharsetNameException ex) {
// Don't add unsupported charsets to the list
}
}
return possibleEncoders;
} catch (IOException | IllegalArgumentException ex) {
logger.log(Level.WARNING, "Failed to detect charset of mbox file.", ex); //NON-NLS
return possibleEncoders;
} finally {
try {
is.close();
} catch (IOException ex) {
logger.log(Level.INFO, "Failed to close input stream"); //NON-NLS
}
}
}
private void addErrorMessage(String msg) {
errors.append("<li>").append(msg).append("</li>"); //NON-NLS
}
}