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
|
// Package ssh implements the SSH transport protocol.
package ssh
import (
"fmt"
"strings"
"gopkg.in/src-d/go-git.v4/plumbing/transport"
"gopkg.in/src-d/go-git.v4/plumbing/transport/internal/common"
"golang.org/x/crypto/ssh"
)
// DefaultClient is the default SSH client.
var DefaultClient = common.NewClient(&runner{})
// DefaultAuthBuilder is the function used to create a default AuthMethod, when
// the user doesn't provide any.
var DefaultAuthBuilder = func(user string) (AuthMethod, error) {
return NewSSHAgentAuth(user)
}
type runner struct{}
func (r *runner) Command(cmd string, ep transport.Endpoint, auth transport.AuthMethod) (common.Command, error) {
c := &command{command: cmd, endpoint: ep}
if auth != nil {
c.setAuth(auth)
}
if err := c.connect(); err != nil {
return nil, err
}
return c, nil
}
type command struct {
*ssh.Session
connected bool
command string
endpoint transport.Endpoint
client *ssh.Client
auth AuthMethod
}
func (c *command) setAuth(auth transport.AuthMethod) error {
a, ok := auth.(AuthMethod)
if !ok {
return transport.ErrInvalidAuthMethod
}
c.auth = a
return nil
}
func (c *command) Start() error {
return c.Session.Start(endpointToCommand(c.command, c.endpoint))
}
// Close closes the SSH session and connection.
func (c *command) Close() error {
if !c.connected {
return nil
}
c.connected = false
//XXX: If did read the full packfile, then the session might be already
// closed.
_ = c.Session.Close()
return c.client.Close()
}
// connect connects to the SSH server, unless a AuthMethod was set with
// SetAuth method, by default uses an auth method based on PublicKeysCallback,
// it connects to a SSH agent, using the address stored in the SSH_AUTH_SOCK
// environment var.
func (c *command) connect() error {
if c.connected {
return transport.ErrAlreadyConnected
}
if c.auth == nil {
if err := c.setAuthFromEndpoint(); err != nil {
return err
}
}
var err error
config := c.auth.clientConfig()
config.HostKeyCallback, err = c.auth.hostKeyCallback()
if err != nil {
return err
}
c.client, err = ssh.Dial("tcp", c.getHostWithPort(), config)
if err != nil {
return err
}
c.Session, err = c.client.NewSession()
if err != nil {
_ = c.client.Close()
return err
}
c.connected = true
return nil
}
func (c *command) getHostWithPort() string {
host := c.endpoint.Host
if strings.Index(c.endpoint.Host, ":") == -1 {
host += ":22"
}
return host
}
func (c *command) setAuthFromEndpoint() error {
var u string
if info := c.endpoint.User; info != nil {
u = info.Username()
}
var err error
c.auth, err = DefaultAuthBuilder(u)
return err
}
func endpointToCommand(cmd string, ep transport.Endpoint) string {
return fmt.Sprintf("%s '%s'", cmd, ep.Path)
}
|
