205 lines
6.5 KiB
Go
205 lines
6.5 KiB
Go
package tor
|
|
|
|
import (
|
|
"crypto/rand"
|
|
"encoding/base64"
|
|
"errors"
|
|
"git.openprivacy.ca/cwtch.im/tapir"
|
|
"git.openprivacy.ca/cwtch.im/tapir/primitives"
|
|
"git.openprivacy.ca/openprivacy/connectivity"
|
|
"git.openprivacy.ca/openprivacy/log"
|
|
"golang.org/x/crypto/ed25519"
|
|
"sync"
|
|
"time"
|
|
)
|
|
|
|
// BaseOnionService is a concrete implementation of the service interface over Tor onion services.
|
|
type BaseOnionService struct {
|
|
connections sync.Map
|
|
acn connectivity.ACN
|
|
id *primitives.Identity
|
|
privateKey ed25519.PrivateKey
|
|
ls connectivity.ListenService
|
|
lock sync.Mutex
|
|
port int
|
|
}
|
|
|
|
// Metrics provides a report of useful information about the status of the service e.g. the number of active
|
|
// connections
|
|
func (s *BaseOnionService) Metrics() tapir.ServiceMetrics {
|
|
s.lock.Lock()
|
|
defer s.lock.Unlock()
|
|
|
|
count := 0
|
|
s.connections.Range(func(key, value interface{}) bool {
|
|
connection := value.(tapir.Connection)
|
|
if !connection.IsClosed() {
|
|
count++
|
|
}
|
|
return true
|
|
})
|
|
|
|
return tapir.ServiceMetrics{
|
|
ConnectionCount: count,
|
|
}
|
|
}
|
|
|
|
// Init initializes a BaseOnionService with a given private key and identity
|
|
// The private key is needed to initialize the Onion listen socket, ideally we could just pass an Identity in here.
|
|
func (s *BaseOnionService) Init(acn connectivity.ACN, sk ed25519.PrivateKey, id *primitives.Identity) {
|
|
// run add onion
|
|
// get listen context
|
|
s.acn = acn
|
|
s.id = id
|
|
s.privateKey = sk
|
|
s.port = 9878
|
|
}
|
|
|
|
// SetPort configures the port that the service uses.
|
|
func (s *BaseOnionService) SetPort(port int) {
|
|
s.port = port
|
|
}
|
|
|
|
// WaitForCapabilityOrClose blocks until the connection has the given capability or the underlying connection is closed
|
|
// (through error or user action)
|
|
func (s *BaseOnionService) WaitForCapabilityOrClose(cid string, name tapir.Capability) (tapir.Connection, error) {
|
|
conn, err := s.GetConnection(cid)
|
|
// If there is at least one active connection, then check the one that is returned and use it
|
|
for conn != nil {
|
|
if conn.HasCapability(name) {
|
|
return conn, nil
|
|
}
|
|
time.Sleep(time.Millisecond * 200)
|
|
// If we received both a Connection and an Error from GetConnection that means we have multiple connections
|
|
// If that was the case we refresh from the connection store as the likely case is one of them has been
|
|
// closed and the other one has the capabilities we need.
|
|
if err != nil {
|
|
conn, err = s.GetConnection(cid)
|
|
}
|
|
}
|
|
// There are no active connections with that hostname
|
|
return nil, err
|
|
}
|
|
|
|
// GetConnection returns a connection for a given hostname.
|
|
func (s *BaseOnionService) GetConnection(hostname string) (tapir.Connection, error) {
|
|
conn := make([]tapir.Connection, 0)
|
|
s.connections.Range(func(key, value interface{}) bool {
|
|
connection := value.(tapir.Connection)
|
|
if connection.Hostname() == hostname {
|
|
if !connection.IsClosed() {
|
|
conn = append(conn, connection)
|
|
return true
|
|
}
|
|
}
|
|
return true
|
|
})
|
|
if len(conn) == 0 {
|
|
return nil, errors.New("no connection found")
|
|
}
|
|
if len(conn) > 1 {
|
|
// If there are multiple connections we return the first one but also notify the user (this should be a
|
|
// temporary edgecase (see Connect))
|
|
return conn[0], errors.New("multiple connections found")
|
|
}
|
|
return conn[0], nil
|
|
}
|
|
|
|
// Connect initializes a new outbound connection to the given peer, using the defined Application
|
|
func (s *BaseOnionService) Connect(hostname string, app tapir.Application) (bool, error) {
|
|
_, err := s.GetConnection(hostname)
|
|
if err == nil {
|
|
// Note: This check is not 100% reliable. And we may end up with two connections between peers
|
|
// This can happen when a client connects to a server as the server is connecting to the client
|
|
// Because at the start of the connection the server cannot derive the true hostname of the client until it
|
|
// has auth'd
|
|
// We mitigate this by performing multiple checks when Connect'ing
|
|
return true, errors.New("already connected to " + hostname)
|
|
}
|
|
// connects to a remote server
|
|
// spins off to a connection struct
|
|
log.Debugf("Connecting to %v", hostname)
|
|
conn, _, err := s.acn.Open(hostname)
|
|
if err == nil {
|
|
connectionID := s.getNewConnectionID()
|
|
|
|
// Second check. If we didn't catch a double connection attempt before the Open we *should* catch it now because
|
|
// the auth protocol is quick and Open over onion connections can take some time.
|
|
// Again this isn't 100% reliable.
|
|
_, err := s.GetConnection(hostname)
|
|
if err == nil {
|
|
conn.Close()
|
|
return true, errors.New("already connected to " + hostname)
|
|
}
|
|
|
|
log.Debugf("Connected to %v [%v]", hostname, connectionID)
|
|
s.connections.Store(connectionID, tapir.NewConnection(s, s.id, hostname, true, conn, app.NewInstance()))
|
|
return true, nil
|
|
}
|
|
log.Debugf("Error connecting to %v %v", hostname, err)
|
|
return false, err
|
|
}
|
|
|
|
func (s *BaseOnionService) getNewConnectionID() string {
|
|
id := make([]byte, 10)
|
|
rand.Read(id)
|
|
connectionID := "connection-" + base64.StdEncoding.EncodeToString(id)
|
|
return connectionID
|
|
}
|
|
|
|
// Listen starts a blocking routine that waits for incoming connections and initializes connections with them based
|
|
// on the given Application.
|
|
func (s *BaseOnionService) Listen(app tapir.Application) error {
|
|
// accepts a new connection
|
|
// spins off to a connection struct
|
|
s.lock.Lock()
|
|
ls, err := s.acn.Listen(s.privateKey, s.port)
|
|
s.ls = ls
|
|
log.Debugf("Starting a service on %v ", ls.AddressFull())
|
|
s.lock.Unlock()
|
|
|
|
if err == nil {
|
|
for {
|
|
conn, err := s.ls.Accept()
|
|
if err == nil {
|
|
tempHostname := s.getNewConnectionID()
|
|
log.Debugf("Accepted connection from %v", tempHostname)
|
|
s.connections.Store(tempHostname, tapir.NewConnection(s, s.id, tempHostname, false, conn, app.NewInstance()))
|
|
} else {
|
|
log.Debugf("Error accepting connection %v", err)
|
|
return err
|
|
}
|
|
}
|
|
}
|
|
log.Debugf("Error listening to connection %v", err)
|
|
return err
|
|
}
|
|
|
|
// Shutdown closes the service and ensures that any connections are closed.
|
|
func (s *BaseOnionService) Shutdown() {
|
|
s.lock.Lock()
|
|
defer s.lock.Unlock()
|
|
if s.ls != nil {
|
|
s.ls.Close()
|
|
}
|
|
s.connections.Range(func(key, value interface{}) bool {
|
|
connection := value.(tapir.Connection)
|
|
connection.Close()
|
|
return true
|
|
})
|
|
}
|
|
|
|
// Broadcast sends a message to all connections who possess the given capability
|
|
func (s *BaseOnionService) Broadcast(message []byte, capability tapir.Capability) error {
|
|
s.lock.Lock()
|
|
defer s.lock.Unlock()
|
|
s.connections.Range(func(key, value interface{}) bool {
|
|
connection := value.(tapir.Connection)
|
|
if connection.HasCapability(capability) {
|
|
connection.Send(message)
|
|
}
|
|
return true
|
|
})
|
|
return nil
|
|
}
|