/
dialer.go
167 lines (143 loc) · 3.61 KB
/
dialer.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
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
package ssh
import (
"context"
"errors"
"net"
"sync"
"time"
"github.com/go-gost/core/dialer"
"github.com/go-gost/core/logger"
md "github.com/go-gost/core/metadata"
ssh_util "github.com/wznpp1/gost_x/internal/util/ssh"
"github.com/wznpp1/gost_x/registry"
"golang.org/x/crypto/ssh"
)
func init() {
registry.DialerRegistry().Register("ssh", NewDialer)
}
type sshDialer struct {
sessions map[string]*sshSession
sessionMutex sync.Mutex
logger logger.Logger
md metadata
options dialer.Options
}
func NewDialer(opts ...dialer.Option) dialer.Dialer {
options := dialer.Options{}
for _, opt := range opts {
opt(&options)
}
return &sshDialer{
sessions: make(map[string]*sshSession),
logger: options.Logger,
options: options,
}
}
func (d *sshDialer) Init(md md.Metadata) (err error) {
if err = d.parseMetadata(md); err != nil {
return
}
return nil
}
// Multiplex implements dialer.Multiplexer interface.
func (d *sshDialer) Multiplex() bool {
return true
}
func (d *sshDialer) Dial(ctx context.Context, addr string, opts ...dialer.DialOption) (conn net.Conn, err error) {
d.sessionMutex.Lock()
defer d.sessionMutex.Unlock()
session, ok := d.sessions[addr]
if session != nil && session.IsClosed() {
delete(d.sessions, addr) // session is dead
ok = false
}
if !ok {
var options dialer.DialOptions
for _, opt := range opts {
opt(&options)
}
conn, err = options.NetDialer.Dial(ctx, "tcp", addr)
if err != nil {
return
}
session = &sshSession{
addr: addr,
conn: conn,
}
d.sessions[addr] = session
}
return session.conn, err
}
// Handshake implements dialer.Handshaker
func (d *sshDialer) Handshake(ctx context.Context, conn net.Conn, options ...dialer.HandshakeOption) (net.Conn, error) {
opts := &dialer.HandshakeOptions{}
for _, option := range options {
option(opts)
}
d.sessionMutex.Lock()
defer d.sessionMutex.Unlock()
if d.md.handshakeTimeout > 0 {
conn.SetDeadline(time.Now().Add(d.md.handshakeTimeout))
defer conn.SetDeadline(time.Time{})
}
session, ok := d.sessions[opts.Addr]
if session != nil && session.conn != conn {
err := errors.New("ssh: unrecognized connection")
d.logger.Error(err)
conn.Close()
delete(d.sessions, opts.Addr)
return nil, err
}
if !ok || session.client == nil {
s, err := d.initSession(ctx, opts.Addr, conn)
if err != nil {
d.logger.Error(err)
conn.Close()
delete(d.sessions, opts.Addr)
return nil, err
}
session = s
go func() {
s.wait()
d.logger.Debug("session closed")
}()
d.sessions[opts.Addr] = session
}
if session.IsClosed() {
delete(d.sessions, opts.Addr)
return nil, ssh_util.ErrSessionDead
}
channel, reqs, err := session.client.OpenChannel(ssh_util.GostSSHTunnelRequest, nil)
if err != nil {
return nil, err
}
go ssh.DiscardRequests(reqs)
return ssh_util.NewConn(conn, channel), nil
}
func (d *sshDialer) initSession(ctx context.Context, addr string, conn net.Conn) (*sshSession, error) {
config := ssh.ClientConfig{
Timeout: 30 * time.Second,
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
}
if d.options.Auth != nil {
config.User = d.options.Auth.Username()
if password, _ := d.options.Auth.Password(); password != "" {
config.Auth = []ssh.AuthMethod{
ssh.Password(password),
}
}
}
if d.md.signer != nil {
config.Auth = append(config.Auth, ssh.PublicKeys(d.md.signer))
}
sshConn, chans, reqs, err := ssh.NewClientConn(conn, addr, &config)
if err != nil {
return nil, err
}
return &sshSession{
conn: conn,
client: ssh.NewClient(sshConn, chans, reqs),
closed: make(chan struct{}),
dead: make(chan struct{}),
}, nil
}