initial commit

README.md

@@ -1,11 +1,15 @@
 ## sendafriend
 
+WARNING: sendafriend has not been audited and probably contains security vulnerabilities. please do not use it for anything sensitive yet
+
 quickly send files or control signals between machines by piping them on the command line, with bidirectional authentication and metadata resistance via tor (built on cwtch)
 
 includes a way to quickly exchange onion addresses using a low-entropy shared secret (using pairwise socialist millionaires' protocol on a bbs) and a contact manager
 
 note that we only support data up to 64k right now, sorry :(  (a fix for this is in the works)
 
+sendafriend is rated Adults Only because it generates random words sometimes and i haven't read all the words personally
+
 ## installation
 
 requires you to have go installed and your gopath configured correctly (sorry)

main.go

@@ -11,10 +11,15 @@ import (
 	"time"
 	"path"
 	"os/user"
+	"strings"
+	"log"
+	"io/ioutil"
+	"sync"
+	"cwtch.im/cwtch/peer/connections"
 )
 
 func driftoff() {
-	time.Sleep(time.Second * 15)
+	time.Sleep(time.Second * 7)
 	os.Exit(1)
 }
 
@@ -35,6 +40,14 @@ func addContactEntry(peer libpeer.CwtchPeer, name string, onion string) {
 	peer.GetProfile().SetCustomAttribute(name+"_onion", onion)
 }
 
+func exitOnEnter() {
+	fmt.Println("okay, now have your friend type \"sendafriend seek\" and enter the secret")
+	fmt.Println("or press enter to cancel the game and exit")
+	reader := bufio.NewReader(os.Stdin)
+	reader.ReadString('\n')
+	os.Exit(0)
+}
+
 func printHelp() {
 	fmt.Println("usage: sendafriend [command] [options]\nCommands: help, setname, info, list, add, send, receive, hide, seek")
 }
@@ -45,13 +58,15 @@ func main() {
 		os.Exit(1)
 	}
 
-	//log.SetFlags(0)
+	if os.Getenv("SENDAFRIEND_DEBUG") != "YES" {
-	//log.SetOutput(ioutil.Discard)
+		log.SetFlags(0)
+		log.SetOutput(ioutil.Discard)
+	}
 
 	// this is a cwtch server used only to make the "pair" command work
 	// it is completely untrusted and only blinded information is passed through it
 	// it can point to any ol cwtch group, as long as both people running "pair" are using the same one
-	inviteStr := "torv30I0zJgNiUz57gJlxFsp4PUq47WDoKNCL95GEadaLlEE=EsABCiA4MjViZTVjODU0ZDFhNGRhNjM3NmExNTBlYjM2ZjM2NxIgPAl3zAsMfauSZQyiGXlj7u6M6usYN/HqtPD2jafjwTAaOGloZDNlYXdhbjZ2aG1kaDdudDVicXh5aHVlM2k0aXgzb3kyZWZrcHdkaDZyNGptcTNhZXJ0dWlkIkDhF3Ko8nAtEJPvjpCjwFM4py0CeAhYCTc9l9H+Wah8traU15D/JzIHEAKhaDiIzmKqBOECk9Q+G40Y6pXPWKkI"
+	inviteStr := "torv30I0zJgNiUz57gJlxFsp4PUq47WDoKNCL95GEadaLlEE=EsABCiA1MjQzYjNkNzczMjAwNzc1MDExMDI0MjJkM2NkOGNmZBIgsXZKp350ShZ2l3iqOh4ZhGJmj0Etb5QmkL5iLZno9AQaOGZxcWJkNWxrNzRnbG5zZ292aXVuNm92Z3V0MmNqY252Mm12aWdvamNuc21wd3NucTJ5ZGpmM3FkIkD5x/JNhpLVe982dE9+3mp1IEog6O8yGdrIuUs0Tb6F1Fh1J1zuv1nJBFECuzYyF1yhqNvOn9Z6MatXVi+PKQIO"
 
 	var dirname, filename string
 	if os.Getenv("SENDAFRIEND_FOLDER") != "" {
@@ -202,16 +217,17 @@ func main() {
 			os.Exit(1)
 		}
 
-		suggestedSecret, _ := diceware.Generate(1)
+		suggestedSecret, _ := diceware.Generate(2)
-		fmt.Printf("enter a secret that only the two of you would know [%v]: ", suggestedSecret[0])
+		fmt.Printf("enter a secret that only the two of you would know [%v %v]: ", suggestedSecret[0], suggestedSecret[1])
 		in := bufio.NewReader(os.Stdin)
 		secret, _ := in.ReadString('\n')
 		secret = secret[:len(secret)-1]
 
 		if secret == "" {
-			secret = suggestedSecret[0]
+			secret = strings.Join(suggestedSecret, " ")
 		}
 
+		fmt.Println("okay, now please wait a moment while some magic happens...")
 		ephemeralPeer, err := libpeer.NewCwtchPeer("Alice", "alicepass", "")
 		if err != nil {
 			fmt.Printf("couldn't create an ephemeral onion address: %v\n", err)
@@ -226,16 +242,17 @@ func main() {
 
 		group := ephemeralPeer.GetGroup(groupId)
 		ephemeralPeer.JoinServer(group.GroupServer)
-		time.Sleep(time.Second * 30) //TODO: can this be shorter?
+		mp := ephemeralPeer.GetServers()
+		for ; mp[group.GroupServer] != connections.AUTHENTICATED; mp = ephemeralPeer.GetServers() {
+			time.Sleep(time.Millisecond * 500)
+		}
 
 		err = ephemeralPeer.SendMessageToGroup(groupId, "be gay do crimes")
 		if err != nil {
-			fmt.Printf("the hide-n-seek server is down or something? try again i guess\n")
+			fmt.Printf("the hide-n-seek server is down or something? try again i guess; %v\n", err)
 			os.Exit(1)
 		}
 
-		fmt.Println("okay, now have your friend type \"sendafriend seek\" and enter the secret")
-
 		convos := make(map[string]*Conversation)
 		processData := func(onion string, data []byte) []byte {
 			if _, contains := convos[onion]; !contains {
@@ -259,14 +276,8 @@ func main() {
 			return tlv2arr(out)
 		}
 		ephemeralPeer.SetPeerDataHandler(processData)
-		err = ephemeralPeer.Listen()
+		go ephemeralPeer.Listen()
-		if err != nil {
+		exitOnEnter()
-			fmt.Printf("error running ephemeral onion: %v\n", err)
-		}
-
-		fmt.Println("press enter to cancel the game and exit")
-		reader := bufio.NewReader(os.Stdin)
-		reader.ReadString('\n')
 	case "seek":
 		if len(os.Args) != 3 {
 			fmt.Fprintf(os.Stderr, "example: sendafriend seek alice\n")
@@ -277,6 +288,7 @@ func main() {
 		in := bufio.NewReader(os.Stdin)
 		secret, _ := in.ReadString('\n')
 		secret = secret[:len(secret)-1]
+		fmt.Println("okay, now please wait a moment while some magic happens...")
 
 		ephemeralPeer, err := libpeer.NewCwtchPeer("Alice", "alicepass", "")
 		if err != nil {
@@ -292,25 +304,23 @@ func main() {
 
 		group := ephemeralPeer.GetGroup(groupId)
 		ephemeralPeer.JoinServer(group.GroupServer)
-		time.Sleep(time.Second * 10) //TODO: can this be shorter?
 
+		//sadly we cannot listen for messages normally because we want to go in reverse order
 		messages := group.GetTimeline()
+		for ; len(messages) == 0; messages = group.GetTimeline() {
+			time.Sleep(time.Second * 3)
+		}
 
+		var waitGroup sync.WaitGroup
+		fmt.Printf("got advertisements. checking them...")
 		for i := len(messages) - 1; i >= 0; i-- {
-			fmt.Printf("checking advert %d/%d...\n", len(messages)-i, len(messages))
-			//fmt.Printf("%v <%v> %v\n", messages[i].Timestamp, messages[i].PeerID, messages[i].Message)
-
 			if messages[i].Message == "be gay do crimes" {
-				onion, success := doSMP(messages[i].PeerID, secret, os.Args[2], peer.GetProfile().Onion)
+				// this is not as scary as it seems because only one of these goroutines will actually use the peer
-				if success {
+				waitGroup.Add(1)
-					addContactEntry(peer, os.Args[2], onion)
+				go doSMP(peer, messages[i].PeerID, secret, os.Args[2])
-					peer.Save()
-					os.Exit(0)
-				} else {
-					fmt.Printf("debug:fail\n")
-				}
 			}
 		}
+		waitGroup.Wait()
 	}
 
 	peer.Save()

smp.go

@@ -61,8 +61,7 @@ import (
 	"math/big"
 	"os"
 	"strconv"
-	"time"
+	)
-)
 
 func arr2tlv(data []byte) tlv {
 	var typ, len uint16
@@ -83,7 +82,7 @@ func tlv2arr(t tlv) []byte {
 	return ret
 }
 
-func doSMP(onion string, secret string, friendname string, longtermonion string) (string, bool) {
+func doSMP(longtermpeer libpeer.CwtchPeer, onion string, secret string, friendname string) {
 	var alice Conversation
 	secretInt := new(big.Int)
 	secretInt.SetBytes([]byte(secret))
@@ -95,23 +94,22 @@ func doSMP(onion string, secret string, friendname string, longtermonion string)
 		os.Exit(1)
 	}
 
-	var wishandaprayer string
-	var success bool
 	processData := func(onion string, data []byte) []byte {
 		tlvPacket := arr2tlv(data)
 		out, complete, err := alice.processSMP(tlvPacket)
 
 		if tlvPacket.typ == 42 {
 			fmt.Printf("found them! adding %v <%s> to contact list\n", friendname, tlvPacket.data)
-			wishandaprayer = string(tlvPacket.data)
+
-			success = true
+			addContactEntry(longtermpeer, os.Args[2], string(tlvPacket.data))
-			return nil
+			longtermpeer.Save()
+			os.Exit(0)
 		}
 
 		if err != nil {
-			os.Exit(1)
+			return nil
 		} else if complete {
-			finalPacket := tlv{42, uint16(len(longtermonion)), []byte(longtermonion)}
+			finalPacket := tlv{42, uint16(len(longtermpeer.GetProfile().Onion)), []byte(longtermpeer.GetProfile().Onion)}
 			return tlv2arr(finalPacket)
 		}
 
@@ -124,9 +122,6 @@ func doSMP(onion string, secret string, friendname string, longtermonion string)
 	for i := range tlvList {
 		connection.SendPacket(tlv2arr(tlvList[i]))
 	}
-
-	time.Sleep(time.Minute)
-	return wishandaprayer, success
 }
 
 type smpFailure string