diff --git a/cmix/client.go b/cmix/client.go
index 996cacdb46016a7675cde906cbcd9c66dc68c766..d164b4d2a60620176fe7fee12c5a26e95e351c99 100644
--- a/cmix/client.go
+++ b/cmix/client.go
@@ -189,9 +189,14 @@ func (c *client) initialize(ndf *ndf.NetworkDefinition) error {
// Set up critical message tracking (sendCmix only)
critSender := func(msg format.Message, recipient *id.ID, params CMIXParams,
) (id.Round, ephemeral.Id, error) {
- return sendCmixHelper(c.Sender, msg, recipient, params, c.instance,
+ compiler := func(round id.Round) (format.Message, error) {
+ return msg, nil
+ }
+ rid, eid, _, sendErr := sendCmixHelper(c.Sender, compiler, recipient, params, c.instance,
c.session.GetCmixGroup(), c.Registrar, c.rng, c.events,
c.session.GetTransmissionID(), c.comms)
+ return rid, eid, sendErr
+
}
c.crit = newCritical(c.session.GetKV(), c.Monitor,
diff --git a/cmix/interface.go b/cmix/interface.go
index a5db8b3cfe2089e94d03861769785ab99bd4390a..717dbb0bbe8b26a288aaa79427bc6d2ed07a30a6 100644
--- a/cmix/interface.go
+++ b/cmix/interface.go
@@ -290,6 +290,14 @@ type Client interface {
type ClientErrorReport func(source, message, trace string)
+// MessageAssembler func accepts a round ID, returning fingerprint, service, payload & mac.
+// This allows users to pass in a paylaod which will contain the round ID over which the message is sent.
+type MessageAssembler func(rid id.Round) (fingerprint format.Fingerprint, service message.Service, payload, mac []byte)
+
+// messageAssembler is an internal wrapper around MessageAssembler which returns a format.message
+// This is necessary to preserve the interaction between sendCmixHelper and critical messages
+type messageAssembler func(rid id.Round) (format.Message, error)
+
type clientCommsInterface interface {
followNetworkComms
SendCmixCommsInterface
diff --git a/cmix/sendCmix.go b/cmix/sendCmix.go
index 73dfcfbd2c02b6f1cafcf49cd4662826edf7e3e8..648e1ef1c8691211f40bf11fc76e86bc17e5dfe7 100644
--- a/cmix/sendCmix.go
+++ b/cmix/sendCmix.go
@@ -56,34 +56,74 @@ import (
// WARNING: Do not roll your own crypto.
func (c *client) Send(recipient *id.ID, fingerprint format.Fingerprint,
service message.Service, payload, mac []byte, cmixParams CMIXParams) (
+ id.Round, ephemeral.Id, error) {
+ // create an internal assembler function to pass to sendWithAssembler
+ assembler := func(rid id.Round) (format.Fingerprint, message.Service, []byte, []byte) {
+ return fingerprint, service, payload, mac
+ }
+ return c.sendWithAssembler(recipient, assembler, cmixParams)
+}
+
+// SendWithAssembler sends a variable cmix payload to the provided recipient.
+// The payload sent is based on the Complier function passed in, which accepts
+// a round ID and returns the necessary payload data.
+// Returns the round ID of the round the payload was sent or an error if it
+// fails.
+// This does not have end-to-end encryption on it and is used exclusively as
+// a send for higher order cryptographic protocols. Do not use unless
+// implementing a protocol on top.
+// recipient - cMix ID of the recipient.
+// assembler - MessageAssembler function, accepting round ID and returning fingerprint
+// format.Fingerprint, service message.Service, payload, mac []byte
+// Will return an error if the network is unhealthy or if it fails to send
+// (along with the reason). Blocks until successful sends or errors.
+// WARNING: Do not roll your own crypto.
+func (c *client) SendWithAssembler(recipient *id.ID, assembler MessageAssembler, cmixParams CMIXParams) (
+ id.Round, ephemeral.Id, error) {
+ // Critical messaging and assembler-based message payloads are not compatible
+ if cmixParams.Critical {
+ return 0, ephemeral.Id{}, errors.New("Cannot send critical messages with a message assembler")
+ }
+ return c.sendWithAssembler(recipient, assembler, cmixParams)
+}
+
+// sendWithAssembler wraps the passed in MessageAssembler in a messageAssembler for sendCmixHelper,
+// and sets up critical message handling where applicable.
+func (c *client) sendWithAssembler(recipient *id.ID, assembler MessageAssembler, cmixParams CMIXParams) (
id.Round, ephemeral.Id, error) {
if !c.Monitor.IsHealthy() {
return 0, ephemeral.Id{}, errors.New(
"Cannot send cmix message when the network is not healthy")
}
- if len(payload) != c.maxMsgLen {
- return 0, ephemeral.Id{}, errors.Errorf(
- "bad message length (%d, need %d)",
- len(payload), c.maxMsgLen)
- }
+ // Create an internal messageAssembler which returns a format.Message
+ assemblerFunc := func(rid id.Round) (format.Message, error) {
+ fingerprint, service, payload, mac := assembler(rid)
- // Build message. Will panic if inputs are not correct.
- msg := format.NewMessage(c.session.GetCmixGroup().GetP().ByteLen())
- msg.SetContents(payload)
- msg.SetKeyFP(fingerprint)
- msg.SetSIH(service.Hash(msg.GetContents()))
- msg.SetMac(mac)
+ if len(payload) != c.maxMsgLen {
+ return format.Message{}, errors.Errorf(
+ "bad message length (%d, need %d)",
+ len(payload), c.maxMsgLen)
+ }
- jww.TRACE.Printf("sendCmix Contents: %v, KeyFP: %v, MAC: %v, SIH: %v",
- msg.GetContents(), msg.GetKeyFP(), msg.GetMac(),
- msg.GetSIH())
+ // Build message. Will panic if inputs are not correct.
+ msg := format.NewMessage(c.session.GetCmixGroup().GetP().ByteLen())
+ msg.SetContents(payload)
+ msg.SetKeyFP(fingerprint)
+ msg.SetSIH(service.Hash(msg.GetContents()))
+ msg.SetMac(mac)
- if cmixParams.Critical {
- c.crit.AddProcessing(msg, recipient, cmixParams)
+ jww.TRACE.Printf("sendCmix Contents: %v, KeyFP: %v, MAC: %v, SIH: %v",
+ msg.GetContents(), msg.GetKeyFP(), msg.GetMac(),
+ msg.GetSIH())
+
+ if cmixParams.Critical {
+ c.crit.AddProcessing(msg, recipient, cmixParams)
+ }
+ return msg, nil
}
- rid, ephID, rtnErr := sendCmixHelper(c.Sender, msg, recipient, cmixParams,
+ rid, ephID, msg, rtnErr := sendCmixHelper(c.Sender, assemblerFunc, recipient, cmixParams,
c.instance, c.session.GetCmixGroup(), c.Registrar, c.rng, c.events,
c.session.GetTransmissionID(), c.comms)
@@ -104,10 +144,10 @@ func (c *client) Send(recipient *id.ID, fingerprint format.Fingerprint,
// If the message is successfully sent, the ID of the round sent it is returned,
// which can be registered with the network instance to get a callback on its
// status.
-func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
+func sendCmixHelper(sender gateway.Sender, assembler messageAssembler, recipient *id.ID,
cmixParams CMIXParams, instance *network.Instance, grp *cyclic.Group,
nodes nodes.Registrar, rng *fastRNG.StreamGenerator, events event.Reporter,
- senderId *id.ID, comms SendCmixCommsInterface) (id.Round, ephemeral.Id, error) {
+ senderId *id.ID, comms SendCmixCommsInterface) (id.Round, ephemeral.Id, format.Message, error) {
timeStart := netTime.Now()
maxTimeout := sender.GetHostParams().SendTimeout
@@ -120,15 +160,11 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
}
jww.INFO.Printf("[Send-%s] Looking for round to send cMix message to "+
- "%s (msgDigest: %s)", cmixParams.DebugTag, recipient, msg.Digest())
+ "%s", cmixParams.DebugTag, recipient)
stream := rng.GetStream()
defer stream.Close()
- // Flip leading bits randomly to thwart a tagging attack.
- // See cmix.SetGroupBits for more info.
- cmix.SetGroupBits(msg, grp, stream)
-
for numRoundTries := uint(0); numRoundTries < cmixParams.RoundTries; numRoundTries++ {
elapsed := netTime.Since(timeStart)
jww.TRACE.Printf("[Send-%s] try %d, elapsed: %s",
@@ -136,15 +172,15 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
if elapsed > cmixParams.Timeout {
jww.INFO.Printf("[Send-%s] No rounds to send to %s "+
- "(msgDigest: %s) were found before timeout %s",
- cmixParams.DebugTag, recipient, msg.Digest(), cmixParams.Timeout)
- return 0, ephemeral.Id{}, errors.New("Sending cmix message timed out")
+ "were found before timeout %s",
+ cmixParams.DebugTag, recipient, cmixParams.Timeout)
+ return 0, ephemeral.Id{}, format.Message{}, errors.New("Sending cmix message timed out")
}
if numRoundTries > 0 {
jww.INFO.Printf("[Send-%s] Attempt %d to find round to send "+
- "message to %s (msgDigest: %s)", cmixParams.DebugTag,
- numRoundTries+1, recipient, msg.Digest())
+ "message to %s", cmixParams.DebugTag,
+ numRoundTries+1, recipient)
}
// Find the best round to send to, excluding attempted rounds
@@ -152,8 +188,8 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
bestRound, err := instance.GetWaitingRounds().GetUpcomingRealtime(
remainingTime, attempted, sendTimeBuffer)
if err != nil {
- jww.WARN.Printf("[Send-%s] Failed to GetUpcomingRealtime "+
- "(msgDigest: %s): %+v", cmixParams.DebugTag, msg.Digest(), err)
+ jww.WARN.Printf("[Send-%s] Failed to GetUpcomingRealtime: "+
+ "%+v", cmixParams.DebugTag, err)
}
if bestRound == nil {
@@ -185,6 +221,16 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
continue
}
+ msg, err := assembler(id.Round(bestRound.ID))
+ if err != nil {
+ jww.ERROR.Printf("Failed to compile message: %+v", err)
+ return 0, ephemeral.Id{}, format.Message{}, err
+ }
+
+ // Flip leading bits randomly to thwart a tagging attack.
+ // See cmix.SetGroupBits for more info.
+ cmix.SetGroupBits(msg, grp, stream)
+
// Retrieve host and key information from round
firstGateway, roundKeys, err := processRound(
nodes, bestRound, recipient.String(), msg.Digest())
@@ -201,7 +247,7 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
wrappedMsg, encMsg, ephID, err := buildSlotMessage(msg, recipient,
firstGateway, stream, senderId, bestRound, roundKeys)
if err != nil {
- return 0, ephemeral.Id{}, err
+ return 0, ephemeral.Id{}, format.Message{}, err
}
jww.INFO.Printf("[Send-%s] Sending to EphID %d (%s), on round %d "+
@@ -251,7 +297,7 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
// Exit if the thread has been stopped
if stoppable.CheckErr(err) {
- return 0, ephemeral.Id{}, err
+ return 0, ephemeral.Id{}, format.Message{}, err
}
// If the comm errors or the message fails to send, continue retrying
@@ -260,7 +306,7 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
jww.ERROR.Printf("[Send-%s] SendCmix failed to send to "+
"EphID %d (%s) on round %d: %+v", cmixParams.DebugTag,
ephID.Int64(), recipient, bestRound.ID, err)
- return 0, ephemeral.Id{}, err
+ return 0, ephemeral.Id{}, format.Message{}, err
}
jww.ERROR.Printf("[Send-%s] SendCmix failed to send to "+
@@ -280,7 +326,7 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
jww.INFO.Print(m)
events.Report(1, "MessageSend", "Metric", m)
- return id.Round(bestRound.ID), ephID, nil
+ return id.Round(bestRound.ID), ephID, msg, nil
} else {
jww.FATAL.Panicf("[Send-%s] Gateway %s returned no error, "+
"but failed to accept message when sending to EphID %d (%s) "+
@@ -289,6 +335,6 @@ func sendCmixHelper(sender gateway.Sender, msg format.Message, recipient *id.ID,
}
}
- return 0, ephemeral.Id{},
+ return 0, ephemeral.Id{}, format.Message{},
errors.New("failed to send the message, unknown error")
}
diff --git a/go.mod b/go.mod
index c07f1e0a18e016ce446e62ec1e45d7f0c2bec363..5bb8e838962b73a263217f083138058fcdb87375 100644
--- a/go.mod
+++ b/go.mod
@@ -13,7 +13,7 @@ require (
github.com/spf13/viper v1.12.0
gitlab.com/elixxir/bloomfilter v0.0.0-20211222005329-7d931ceead6f
gitlab.com/elixxir/comms v0.0.4-0.20220805121030-b95005ac4528
- gitlab.com/elixxir/crypto v0.0.7-0.20220606201132-c370d5039cea
+ gitlab.com/elixxir/crypto v0.0.7-0.20220808171640-473891de4c46
gitlab.com/elixxir/ekv v0.1.7
gitlab.com/elixxir/primitives v0.0.3-0.20220606195757-40f7a589347f
gitlab.com/xx_network/comms v0.0.4-0.20220630163702-f3d372ef6acd
diff --git a/go.sum b/go.sum
index 35b35f27bea260a64edf8071d298894195082a41..cccd675d6b722e0aaac060aeb9f6d0c0bd2630a2 100644
--- a/go.sum
+++ b/go.sum
@@ -429,8 +429,8 @@ gitlab.com/elixxir/comms v0.0.4-0.20220805121030-b95005ac4528/go.mod h1:Zi1O21+p
gitlab.com/elixxir/crypto v0.0.0-20200804182833-984246dea2c4/go.mod h1:ucm9SFKJo+K0N2GwRRpaNr+tKXMIOVWzmyUD0SbOu2c=
gitlab.com/elixxir/crypto v0.0.3/go.mod h1:ZNgBOblhYToR4m8tj4cMvJ9UsJAUKq+p0gCp07WQmhA=
gitlab.com/elixxir/crypto v0.0.7-0.20220317172048-3de167bd9406/go.mod h1:tD6XjtQh87T2nKZL5I/pYPck5M2wLpkZ1Oz7H/LqO10=
-gitlab.com/elixxir/crypto v0.0.7-0.20220606201132-c370d5039cea h1:+FjwbKl6X9TDT7qd7gG5N5PSbziPWP3NgjK5ci1b7/8=
-gitlab.com/elixxir/crypto v0.0.7-0.20220606201132-c370d5039cea/go.mod h1:Oy+VWQ2Sa0Ybata3oTV+Yc46hkaDwAsuIMW0wJ01z2M=
+gitlab.com/elixxir/crypto v0.0.7-0.20220808171640-473891de4c46 h1:C8nAiMnL8IOGjQ5qErbpzAjRMVFMoB1GunYk8pGOEz8=
+gitlab.com/elixxir/crypto v0.0.7-0.20220808171640-473891de4c46/go.mod h1:Oy+VWQ2Sa0Ybata3oTV+Yc46hkaDwAsuIMW0wJ01z2M=
gitlab.com/elixxir/ekv v0.1.7 h1:OW2z+N4QCqqMFzouAwFTWWMKz0Y/PDhyYReN7gQ5NiQ=
gitlab.com/elixxir/ekv v0.1.7/go.mod h1:e6WPUt97taFZe5PFLPb1Dupk7tqmDCTQu1kkstqJvw4=
gitlab.com/elixxir/primitives v0.0.0-20200731184040-494269b53b4d/go.mod h1:OQgUZq7SjnE0b+8+iIAT2eqQF+2IFHn73tOo+aV11mg=