forked from rancher/remotedialer
/
server.go
125 lines (105 loc) · 2.94 KB
/
server.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
package remotedialer
import (
"net/http"
"sync"
"time"
"github.com/gorilla/websocket"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
var (
errFailedAuth = errors.New("failed authentication")
errWrongMessageType = errors.New("wrong websocket message type")
)
type Authorizer func(req *http.Request) (clientKey string, authed bool, err error)
type ErrorWriter func(rw http.ResponseWriter, req *http.Request, code int, err error)
type OnConnect func(req *http.Request) error
type OnDisconnect func(req *http.Request)
func DefaultErrorWriter(rw http.ResponseWriter, req *http.Request, code int, err error) {
rw.Write([]byte(err.Error()))
rw.WriteHeader(code)
}
type Server struct {
PeerID string
PeerToken string
authorizer Authorizer
errorWriter ErrorWriter
onConnect OnConnect
onDisconnect OnDisconnect
sessions *sessionManager
peers map[string]peer
peerLock sync.Mutex
}
func New(auth Authorizer, errorWriter ErrorWriter) *Server {
return &Server{
peers: map[string]peer{},
authorizer: auth,
errorWriter: errorWriter,
sessions: newSessionManager(),
}
}
func (s *Server) OnConnect(cb OnConnect) {
s.onConnect = cb
}
func (s *Server) OnDisconnect(cb OnDisconnect) {
s.onDisconnect = cb
}
func (s *Server) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
clientKey, authed, peer, err := s.auth(req)
if err != nil {
s.errorWriter(rw, req, 400, err)
return
}
if !authed {
s.errorWriter(rw, req, 401, errFailedAuth)
return
}
logrus.Infof("Handling backend connection request [%s]", clientKey)
upgrader := websocket.Upgrader{
HandshakeTimeout: 5 * time.Second,
CheckOrigin: func(r *http.Request) bool { return true },
Error: s.errorWriter,
}
wsConn, err := upgrader.Upgrade(rw, req, nil)
if err != nil {
s.errorWriter(rw, req, 400, errors.Wrapf(err, "Error during upgrade for host [%v]", clientKey))
return
}
session := s.sessions.add(clientKey, wsConn, peer)
defer s.sessions.remove(session)
// handle connect callback
if s.onConnect != nil {
err = s.onConnect(req)
if err != nil {
logrus.Infof("Error finish Connect Callback function for request [%s]: %v", clientKey, err)
return
}
}
// handle disconnect callback
defer func() {
if s.onDisconnect != nil {
s.onDisconnect(req)
}
}()
// Don't need to associate req.Context() to the Session, it will cancel otherwise
code, err := session.Serve()
if err != nil {
// Hijacked so we can't write to the client
logrus.Infof("error in remotedialer server [%d]: %v", code, err)
}
}
func (s *Server) auth(req *http.Request) (clientKey string, authed, peer bool, err error) {
id := req.Header.Get(ID)
token := req.Header.Get(Token)
if id != "" && token != "" {
// peer authentication
s.peerLock.Lock()
p, ok := s.peers[id]
s.peerLock.Unlock()
if ok && p.token == token {
return id, true, true, nil
}
}
id, authed, err = s.authorizer(req)
return id, authed, false, err
}