func deferVerify(d []byte) (*message.Curve25519Key, *[message.MessageIDSize]byte, error) {
var keyHeader [message.KeyHeaderSize]byte
msg, err := message.Base64Message(d).Decode()
if err != nil {
return nil, nil, err
}
messageID := message.CalcMessageID(msg)
copy(keyHeader[:], msg[message.SignHeaderSize:message.SignHeaderSize+message.KeyHeaderSize])
_, recKeys, _ := message.ParseKeyHeader(&keyHeader)
return recKeys.ConstantPubKey, messageID, nil
}
// CmdDecrypt implements decryption functions
func CmdDecrypt() int {
var inData, decMessage []byte
var err error
var meta *message.MetaDataRecieve
var privkeystr string
var nullKey message.Curve25519Key
if OptionsVar.Server == "" {
getPeers(false)
}
if OptionsVar.Stmdir != "" && !isDir(OptionsVar.Stmdir) {
log.Fatalf("stmdir does not exist or is no directory: %s\n", OptionsVar.Stmdir)
return 1
}
// Read input data
maxInData := int64(GlobalConfigVar.BodyLength+message.KeyHeaderSize+message.SignHeaderSize) * 4
// Read data from stdin or file
if len(flag.Args()) == 0 {
inData, err = inputData(OptionsVar.Infile, maxInData)
if err != nil {
log.Fatalf("No input data: %s\n", err)
return 1
}
} else {
// read data from server (Get). CMDLine is [server/]messageid[_privatekey]
var messageidcl []byte
var server string
server, messageidcl, privkeystr = cmdlineURLparse(flag.Args()...)
if server == "" {
server = OptionsVar.Server
}
proto := repproto.New(OptionsVar.Socksserver, OptionsVar.Server, GlobalConfigVar.PasteServers...)
if server == "" {
server, inData, err = proto.Get(messageidcl)
} else {
inData, err = proto.GetSpecific(server, messageidcl)
}
if err != nil {
log.Fatalf("Fetch error: %s\n", err)
return 1
}
log.Dataf("STATUS (FetchServer):\t%s\n", server)
}
if len(inData) < (message.KeyHeaderSize+message.SignHeaderSize)*4 {
log.Fatals("No input data.\n")
return 1
}
// Set up receiver parameters
receiver := message.Receiver{
HashCashBits: GlobalConfigVar.MinHashCash,
}
if OptionsVar.Senderkey != "" {
receiver.SenderPublicKey, _ = utils.ParseKeyPair(OptionsVar.Senderkey)
}
// Select private key to use
if OptionsVar.Keymgt < 0 {
if privkeystr == "" { // might have been set from commandline
privkeystr = selectPrivKey(OptionsVar.Privkey, GlobalConfigVar.PrivateKey, "tty")
}
// Parse privkey
if privkeystr != "" {
receiver.ReceiveConstantPrivateKey, receiver.ReceiveTemporaryPrivateKey = utils.ParseKeyPair(privkeystr)
}
} else {
// Register callback, OptionsVar.keymgt == fd
keyMgtFile, callback := KeyCallBack(OptionsVar.Keymgt)
defer keyMgtFile.Close()
receiver.KeyCallBack = callback
}
log.Datas("STATUS (Process):\tREAD\n")
// Decrypt
decMessage, meta, err = receiver.Decrypt(inData)
if err != nil {
log.Fatalf("%s\n", err)
return 1
}
log.Dataf("STATUS (MessageID):\t%s\n", utils.B58encode(meta.MessageID[:]))
log.Dataf("STATUS (RecPubKey):\t%s\n", utils.B58encode(meta.ReceiveConstantPublicKey[:]))
log.Dataf("STATUS (SenderPubKey):\t%s\n", utils.B58encode(meta.SenderConstantPublicKey[:]))
// Get replyKeys
embedConstant, embedTemporary := utils.DecodeEmbedded(decMessage[:message.Curve25519KeySize*2])
if *embedConstant != nullKey {
log.Dataf("STATUS (EmbedPublicKey):\t%s_%s\n", utils.B58encode(embedConstant[:]), utils.B58encode(embedTemporary[:]))
}
// If messageType list: print list to DATA
if meta.MessageType == message.MsgTypeList {
log.Datas("STATUS (Process):\tLIST\n")
err := utils.VerifyListContent(decMessage[message.Curve25519KeySize*2:])
if err != nil {
log.Fatalf("%s\n", err)
return 1
}
lines := bytes.Split(decMessage[message.Curve25519KeySize*2:], []byte("\n"))
for _, l := range lines {
log.Dataf("STATUS (ListItem):\t%s\n", string(l))
}
return 0
}
decMessage = decMessage[message.Curve25519KeySize*2:]
// meta.MessageType
if meta.MessageType == message.MsgTypeRepost {
log.Datas("STATUS (Process):\tREPOST\n")
// If messageType repost: get padkey,mindelay,maxdelay. Repad
padkey, minDelay, maxDelay := utils.DecodeRepostHeader(decMessage[:utils.RepostHeaderSize])
timePoint := utils.STM(int(minDelay), int(maxDelay))
log.Dataf("STATUS (STM):\t%d %d %d\n", minDelay, maxDelay, timePoint)
repostMsgt := message.RePad(decMessage[utils.RepostHeaderSize:], padkey, GlobalConfigVar.BodyLength)
signHeader := new([message.SignHeaderSize]byte)
copy(signHeader[:], repostMsgt[:message.SignHeaderSize])
details, err := message.VerifySignature(*signHeader, GlobalConfigVar.MinHashCash)
if err != nil {
log.Fatalf("%s\n", err)
return 1
}
msgIDMsg := message.CalcMessageID(repostMsgt)
if *msgIDMsg != details.MsgID {
log.Fatals("MessageID conflict\n")
return 1
}
log.Dataf("STATUS (MessageIDSig):\t%s\n", utils.B58encode(details.MsgID[:]))
log.Dataf("STATUS (PubKeySig):\t%s\n", utils.B58encode(details.PublicKey[:]))
log.Dataf("STATUS (NonceSig):\t%x\n", details.HashCashNonce[:])
log.Dataf("STATUS (BitsSig):\t%d\n", details.HashCashBits)
decMessage = message.EncodeBase64(repostMsgt)
if OptionsVar.Stmdir != "" { // Exist/Dir test done early
filename := fmt.Sprintf("%s%s%d.%s", OptionsVar.Stmdir, string(os.PathSeparator), timePoint, utils.B58encode(msgIDMsg[:]))
log.Dataf("STATUS (STMFile):\t%s\n", filename)
err := utils.WriteNewFile(filename, decMessage)
if err != nil {
log.Fatalf("%s\n", err)
return 1
}
return 0
}
}
err = outputData(OptionsVar.Outfile, decMessage)
if err != nil {
log.Fatalf("Output failed: %s\n", err)
return 1
}
return 0
}