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Code Issues Projects Releases Wiki Activity

Nested user-defined objects (and collections of them) can now be read

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by registering ObjectReaders with the Reader.
This commit is contained in:
akwizgran
2011-07-19 17:17:45 +01:00
parent a9e7cbd05c
commit fb528a85ad
22 changed files with 414 additions and 177 deletions
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88
components/net/sf/briar/protocol/MessageReader.java
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@@ -2,12 +2,94 @@ package net.sf.briar.protocol;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.security.PublicKey;
import java.security.Signature;
import java.security.SignatureException;
import java.security.spec.InvalidKeySpecException;
import net.sf.briar.api.crypto.KeyParser;
import net.sf.briar.api.protocol.AuthorId;
import net.sf.briar.api.protocol.GroupId;
import net.sf.briar.api.protocol.Message;
import net.sf.briar.api.protocol.MessageId;
import net.sf.briar.api.protocol.Tags;
import net.sf.briar.api.protocol.UniqueId;
import net.sf.briar.api.serial.FormatException;
import net.sf.briar.api.serial.ObjectReader;
import net.sf.briar.api.serial.Reader;
interface MessageReader {
class MessageReader implements ObjectReader<Message> {
Message readMessage(Reader r) throws IOException,
GeneralSecurityException;
private final KeyParser keyParser;
private final Signature signature;
private final MessageDigest messageDigest;
MessageReader(KeyParser keyParser, Signature signature,
MessageDigest messageDigest) {
this.keyParser = keyParser;
this.signature = signature;
this.messageDigest = messageDigest;
}
public Message readObject(Reader reader) throws IOException {
CopyingConsumer copying = new CopyingConsumer();
CountingConsumer counting = new CountingConsumer(Message.MAX_SIZE);
reader.addConsumer(copying);
reader.addConsumer(counting);
// Read the parent's message ID
reader.readUserDefinedTag(Tags.MESSAGE_ID);
byte[] b = reader.readRaw();
if(b.length != UniqueId.LENGTH) throw new FormatException();
MessageId parent = new MessageId(b);
// Read the group ID
reader.readUserDefinedTag(Tags.GROUP_ID);
b = reader.readRaw();
if(b.length != UniqueId.LENGTH) throw new FormatException();
GroupId group = new GroupId(b);
// Read the timestamp
reader.readUserDefinedTag(Tags.TIMESTAMP);
long timestamp = reader.readInt64();
if(timestamp < 0L) throw new FormatException();
// Hash the author's nick and public key to get the author ID
DigestingConsumer digesting = new DigestingConsumer(messageDigest);
messageDigest.reset();
reader.addConsumer(digesting);
reader.readUserDefinedTag(Tags.NICKNAME);
reader.readString();
reader.readUserDefinedTag(Tags.PUBLIC_KEY);
byte[] encodedKey = reader.readRaw();
reader.removeConsumer(digesting);
AuthorId author = new AuthorId(messageDigest.digest());
// Skip the message body
reader.readUserDefinedTag(Tags.MESSAGE_BODY);
reader.readRaw();
// Record the length of the signed data
int messageLength = (int) counting.getCount();
// Read the signature
reader.readUserDefinedTag(Tags.SIGNATURE);
byte[] sig = reader.readRaw();
reader.removeConsumer(counting);
reader.removeConsumer(copying);
// Verify the signature
PublicKey publicKey;
try {
publicKey = keyParser.parsePublicKey(encodedKey);
} catch(InvalidKeySpecException e) {
throw new FormatException();
}
byte[] raw = copying.getCopy();
try {
signature.initVerify(publicKey);
signature.update(raw, 0, messageLength);
if(!signature.verify(sig)) throw new SignatureException();
} catch(GeneralSecurityException e) {
throw new FormatException();
}
// Hash the message, including the signature, to get the message ID
messageDigest.reset();
messageDigest.update(raw);
MessageId id = new MessageId(messageDigest.digest());
return new MessageImpl(id, parent, group, author, timestamp, raw);
}
}