Files
go-libp2p/p2p/crypto/secio/interface.go
2016-01-04 05:45:58 -08:00

127 lines
3.1 KiB
Go

// package secio handles establishing secure communication between two peers.
package secio
import (
"io"
ci "github.com/ipfs/go-libp2p/p2p/crypto"
peer "github.com/ipfs/go-libp2p/p2p/peer"
msgio "gx/ipfs/QmRQhVisS8dmPbjBUthVkenn81pBxrx1GxE281csJhm2vL/go-msgio"
context "gx/ipfs/QmZy2y8t9zQH2a1b8q2ZSLKp17ATuJoCNxxyMFG5qFExpt/go-net/context"
)
// SessionGenerator constructs secure communication sessions for a peer.
type SessionGenerator struct {
LocalID peer.ID
PrivateKey ci.PrivKey
}
// NewSession takes an insecure io.ReadWriter, sets up a TLS-like
// handshake with the other side, and returns a secure session.
// The handshake isn't run until the connection is read or written to.
// See the source for the protocol details and security implementation.
// The provided Context is only needed for the duration of this function.
func (sg *SessionGenerator) NewSession(ctx context.Context, insecure io.ReadWriteCloser) (Session, error) {
return newSecureSession(ctx, sg.LocalID, sg.PrivateKey, insecure)
}
type Session interface {
// ReadWriter returns the encrypted communication channel
ReadWriter() msgio.ReadWriteCloser
// LocalPeer retrieves the local peer.
LocalPeer() peer.ID
// LocalPrivateKey retrieves the local private key
LocalPrivateKey() ci.PrivKey
// RemotePeer retrieves the remote peer.
RemotePeer() peer.ID
// RemotePublicKey retrieves the remote's public key
// which was received during the handshake.
RemotePublicKey() ci.PubKey
// Close closes the secure session
Close() error
}
// SecureReadWriter returns the encrypted communication channel
func (s *secureSession) ReadWriter() msgio.ReadWriteCloser {
if err := s.Handshake(); err != nil {
return &closedRW{err}
}
return s.secure
}
// LocalPeer retrieves the local peer.
func (s *secureSession) LocalPeer() peer.ID {
return s.localPeer
}
// LocalPrivateKey retrieves the local peer's PrivateKey
func (s *secureSession) LocalPrivateKey() ci.PrivKey {
return s.localKey
}
// RemotePeer retrieves the remote peer.
func (s *secureSession) RemotePeer() peer.ID {
if err := s.Handshake(); err != nil {
return ""
}
return s.remotePeer
}
// RemotePeer retrieves the remote peer.
func (s *secureSession) RemotePublicKey() ci.PubKey {
if err := s.Handshake(); err != nil {
return nil
}
return s.remote.permanentPubKey
}
// Close closes the secure session
func (s *secureSession) Close() error {
s.cancel()
s.handshakeMu.Lock()
defer s.handshakeMu.Unlock()
if s.secure == nil {
return s.insecure.Close() // hadn't secured yet.
}
return s.secure.Close()
}
// closedRW implements a stub msgio interface that's already
// closed and errored.
type closedRW struct {
err error
}
func (c *closedRW) Read(buf []byte) (int, error) {
return 0, c.err
}
func (c *closedRW) Write(buf []byte) (int, error) {
return 0, c.err
}
func (c *closedRW) NextMsgLen() (int, error) {
return 0, c.err
}
func (c *closedRW) ReadMsg() ([]byte, error) {
return nil, c.err
}
func (c *closedRW) WriteMsg(buf []byte) error {
return c.err
}
func (c *closedRW) Close() error {
return c.err
}
func (c *closedRW) ReleaseMsg(m []byte) {
}