start through server invitation process

client/identity.go

@@ -31,6 +31,7 @@ type Identity struct {
 	OwnedDevices         PeerList             `json:"owned_devices,omitempty"`
 	StaticMtkServerPaths []InternalServerList `json:"static_mtk_server_paths,omitempty"`
 	DynamicMtkServeRules []string             `json:"dynamic_mtk_serve_rules,omitempty"`
+	InvitationTimeout    int                  `json:"invitation_timeout,omitempty"`
 	unlockedHiddenPeers  PeerList
 }
 

client/server.go

@@ -100,6 +100,24 @@ func (ints *InternalServer) BuildMessageRequestMessage(lookupKeys []string) ([]b
 	return out, nil
 }
 
+// Creates a basic message to server from a single packed user message and returns it as protobuf serialized byte array
+func (ints *InternalServer) BuildToServerMessageInvitation(invitation *meowlib.ContactCard, password string, timeout int, urllen int) (*meowlib.ToServerMessage, error) {
+	var msg meowlib.ToServerMessage
+	var inv meowlib.Invitation
+	payload, err := invitation.Compress()
+	if err != nil {
+		return nil, err
+	}
+	msg.Type = "1"
+	msg.From = ints.Me.Public
+	inv.Password = password
+	inv.Timeout = int32(timeout)
+	inv.Urllen = int32(urllen)
+	inv.Payload = payload
+	msg.Invitation = &inv
+	return &msg, nil
+}
+
 func (ints *InternalServer) PackServerMessage(payload []byte, signature []byte) (protoPackedMessage []byte, err error) {
 	var msg meowlib.PackedServerMessage
 	msg.From = ints.Me.Public

pb/messages.proto

@@ -15,6 +15,16 @@ message PackedServerMessage {
 	bytes signature = 3; // The message signature with the client public key |eo| the reference to teh symetrical key used
 }
 
+// structure to hold an invitation through a server
+message Invitation {
+    bytes payload = 1;
+    int32 timeout = 2;
+    int32 urllen = 3;
+    string password = 4;
+    string url = 5;
+    int64 expiry = 6;
+}
+
 // structure defining a message for a server, that will be encrypted, then sent in a "packedmessage" payload
 message ToServerMessage {
 	string type = 1; // Type 1 : final destination / 2 : forward 
@@ -39,6 +49,8 @@ message ToServerMessage {
     
     string uuid = 8;
 
+    Invitation invitation = 9;
+
 }
 
 // structure defining a from server receiver message decrypted from a "packedmessage" payload
@@ -57,6 +69,8 @@ message FromServerMessage {
 
     repeated Server knownServers = 7; 
 
+    Invitation invitation = 8;
+
 }
 
 message MatriochkaServer {

server/invitation.go

@@ -0,0 +1,70 @@
+package server
+
+import (
+	"errors"
+	"math/rand"
+	"time"
+
+	"github.com/go-redis/redis"
+)
+
+func (r *RedisRouter) CreateInvitation(invitation []byte, timeout int, password string, serverTimeout int, urlLen int) (string, time.Time) {
+	id := r.createShortUrl(urlLen)
+	if timeout > serverTimeout {
+		timeout = serverTimeout
+	}
+	r.Client.Set("mwiv:"+id, invitation, time.Duration(timeout*1000000))
+	if len(password) > 0 {
+		r.Client.Set("mwpw:"+id, password, time.Duration(timeout*1000000))
+	}
+	return id, time.Now().Add(time.Duration(timeout * 1000000)).UTC()
+}
+
+func (r *RedisRouter) GetInvitation(id string, password string) ([]byte, error) {
+	passRequired := false
+	expectedpass, err := r.Client.Get("mwpw:" + id).Result()
+	if err != nil {
+		passRequired = false
+	} else {
+		passRequired = true
+	}
+	if passRequired && password != expectedpass {
+		return nil, errors.New("invitation get : auth failed, wrong password")
+	}
+	mwiv, err := r.Client.Get("mwiv:" + id).Result()
+	if err != nil {
+		return nil, err
+	}
+	return []byte(mwiv), nil
+}
+
+func (r *RedisRouter) AnswerInvitation(id string, timeout int, invitation []byte, serverTimeout int) time.Time {
+	if timeout > serverTimeout {
+		timeout = serverTimeout
+	}
+	r.Client.Set("mwan:"+id, invitation, time.Duration(timeout*1000000))
+	return time.Now().Add(time.Duration(timeout * 1000000)).UTC()
+}
+
+func (r *RedisRouter) GetAnswer(id string) ([]byte, error) {
+	mwan, err := r.Client.Get("mwiv:" + id).Result()
+	if err != nil {
+		return nil, err
+	}
+	return []byte(mwan), nil
+}
+
+func (r *RedisRouter) createShortUrl(length int) string {
+	url := ""
+	alphabet := "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	// for not in redis
+	for {
+		for i := 1; i <= length; i++ {
+			url += string(alphabet[rand.Intn(61)])
+		}
+		if r.Client.Get("mwiv:"+url).Err() == redis.Nil {
+			break
+		}
+	}
+	return url
+}