summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/gliderlabs/ssh/util.go
blob: 015a44ecc082ae0921b88c44aa8a3038faf491b4 (plain)
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
package ssh

import (
	"crypto/rand"
	"crypto/rsa"
	"encoding/binary"

	"golang.org/x/crypto/ssh"
)

func generateSigner() (ssh.Signer, error) {
	key, err := rsa.GenerateKey(rand.Reader, 2048)
	if err != nil {
		return nil, err
	}
	return ssh.NewSignerFromKey(key)
}

func parsePtyRequest(s []byte) (pty Pty, ok bool) {
	term, s, ok := parseString(s)
	if !ok {
		return
	}
	width32, s, ok := parseUint32(s)
	if !ok {
		return
	}
	height32, _, ok := parseUint32(s)
	if !ok {
		return
	}
	pty = Pty{
		Term: term,
		Window: Window{
			Width:  int(width32),
			Height: int(height32),
		},
	}
	return
}

func parseWinchRequest(s []byte) (win Window, ok bool) {
	width32, s, ok := parseUint32(s)
	if width32 < 1 {
		ok = false
	}
	if !ok {
		return
	}
	height32, _, ok := parseUint32(s)
	if height32 < 1 {
		ok = false
	}
	if !ok {
		return
	}
	win = Window{
		Width:  int(width32),
		Height: int(height32),
	}
	return
}

func parseString(in []byte) (out string, rest []byte, ok bool) {
	if len(in) < 4 {
		return
	}
	length := binary.BigEndian.Uint32(in)
	if uint32(len(in)) < 4+length {
		return
	}
	out = string(in[4 : 4+length])
	rest = in[4+length:]
	ok = true
	return
}

func parseUint32(in []byte) (uint32, []byte, bool) {
	if len(in) < 4 {
		return 0, nil, false
	}
	return binary.BigEndian.Uint32(in), in[4:], true
}