Jabit/core/src/main/kotlin/ch/dissem/bitmessage/entity/payload/Msg.kt

112 lines
3.6 KiB
Kotlin

/*
* Copyright 2017 Christian Basler
*
* 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 ch.dissem.bitmessage.entity.payload
import ch.dissem.bitmessage.entity.Encrypted
import ch.dissem.bitmessage.entity.Plaintext
import ch.dissem.bitmessage.entity.Plaintext.Type.MSG
import ch.dissem.bitmessage.entity.PlaintextHolder
import ch.dissem.bitmessage.entity.SignedStreamableWriter
import ch.dissem.bitmessage.exception.DecryptionFailedException
import java.io.InputStream
import java.io.OutputStream
import java.nio.ByteBuffer
/**
* Used for person-to-person messages.
*/
class Msg : ObjectPayload, Encrypted, PlaintextHolder {
override val stream: Long
private var encrypted: CryptoBox?
override var plaintext: Plaintext?
private set
private constructor(stream: Long, encrypted: CryptoBox) : super(1) {
this.stream = stream
this.encrypted = encrypted
this.plaintext = null
}
constructor(plaintext: Plaintext) : super(1) {
this.stream = plaintext.stream
this.encrypted = null
this.plaintext = plaintext
}
override val type: ObjectType = ObjectType.MSG
override val isSigned: Boolean = true
override var signature: ByteArray?
get() = plaintext?.signature
set(signature) {
plaintext?.signature = signature ?: throw IllegalStateException("no plaintext data available")
}
override fun encrypt(publicKey: ByteArray) {
this.encrypted = CryptoBox(plaintext ?: throw IllegalStateException("no plaintext data available"), publicKey)
}
@Throws(DecryptionFailedException::class)
override fun decrypt(privateKey: ByteArray) {
plaintext = Plaintext.read(MSG, encrypted!!.decrypt(privateKey))
}
override val isDecrypted: Boolean
get() = plaintext != null
override fun equals(other: Any?): Boolean {
if (this === other) return true
if (other !is Msg) return false
if (!super.equals(other)) return false
return stream == other.stream && (encrypted == other.encrypted || plaintext == other.plaintext)
}
override fun hashCode() = stream.toInt()
override fun writer(): SignedStreamableWriter = Writer(this)
private class Writer(
private val item: Msg
) : SignedStreamableWriter {
val encryptedDataWriter = item.encrypted?.writer()
override fun write(out: OutputStream) {
encryptedDataWriter?.write(out) ?: throw IllegalStateException("Msg must be signed and encrypted before writing it.")
}
override fun write(buffer: ByteBuffer) {
encryptedDataWriter?.write(buffer) ?: throw IllegalStateException("Msg must be signed and encrypted before writing it.")
}
override fun writeBytesToSign(out: OutputStream) {
item.plaintext?.writer(false)?.write(out) ?: throw IllegalStateException("no plaintext data available")
}
}
companion object {
val ACK_LENGTH = 32
@JvmStatic
fun read(input: InputStream, stream: Long, length: Int) = Msg(stream, CryptoBox.read(input, length))
}
}