aboutsummaryrefslogtreecommitdiff
path: root/cmd/cashier/main.go
blob: 8bcc3e76c06d72c75307b31e303edfc6eea3903f (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
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
package main

import (
	"bytes"
	"encoding/json"
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"net"
	"net/http"
	"os"
	"time"

	"github.com/nsheridan/cashier/lib"
	"github.com/pkg/browser"
	"golang.org/x/crypto/ssh"
	"golang.org/x/crypto/ssh/agent"
)

var (
	ca       = flag.String("ca", "http://localhost:10000", "CA server")
	keybits  = flag.Int("bits", 2048, "Key size. Ignored for ed25519 keys")
	validity = flag.Duration("validity", time.Hour*24, "Key validity")
	keytype  = flag.String("key_type", "rsa", "Type of private key to generate - rsa, ecdsa or ed25519")
)

func installCert(a agent.Agent, cert *ssh.Certificate, key key) error {
	pubcert := agent.AddedKey{
		PrivateKey:  key,
		Certificate: cert,
		Comment:     cert.KeyId,
	}
	if err := a.Add(pubcert); err != nil {
		return fmt.Errorf("error importing certificate: %s", err)
	}
	return nil
}

func send(s []byte, token string) (*lib.SignResponse, error) {
	req, err := http.NewRequest("POST", *ca+"/sign", bytes.NewReader(s))
	if err != nil {
		return nil, err
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Add("Accept", "application/json")
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", token))
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return nil, err
	}
	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("Bad response from server: %s", resp.Status)
	}
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}
	c := &lib.SignResponse{}
	if err := json.Unmarshal(body, c); err != nil {
		return nil, err
	}
	return c, nil
}

func sign(pub ssh.PublicKey, token string) (*ssh.Certificate, error) {
	marshaled := ssh.MarshalAuthorizedKey(pub)
	marshaled = marshaled[:len(marshaled)-1]
	s, err := json.Marshal(&lib.SignRequest{
		Key:        string(marshaled),
		ValidUntil: time.Now().Add(*validity),
	})
	if err != nil {
		return nil, err
	}
	resp, err := send(s, token)
	if err != nil {
		return nil, err
	}
	if resp.Status != "ok" {
		return nil, fmt.Errorf("error: %s", resp.Response)
	}
	k, _, _, _, err := ssh.ParseAuthorizedKey([]byte(resp.Response))
	if err != nil {
		return nil, err
	}
	cert, ok := k.(*ssh.Certificate)
	if !ok {
		return nil, fmt.Errorf("did not receive a certificate from server")
	}
	return cert, nil
}

func main() {
	flag.Parse()

	fmt.Printf("Your browser has been opened to visit %s\n", *ca)
	if err := browser.OpenURL(*ca); err != nil {
		fmt.Println("Error launching web browser. Go to the link in your web browser")
	}
	fmt.Println("Generating new key pair")
	priv, pub, err := generateKey(*keytype, *keybits)
	if err != nil {
		log.Fatalln("Error generating key pair: ", err)
	}

	fmt.Print("Enter token: ")
	var token string
	fmt.Scanln(&token)

	cert, err := sign(pub, token)
	if err != nil {
		log.Fatalln(err)
	}
	sock, err := net.Dial("unix", os.Getenv("SSH_AUTH_SOCK"))
	if err != nil {
		log.Fatalln("Error connecting to agent: %s", err)
	}
	defer sock.Close()
	a := agent.NewClient(sock)
	if err := installCert(a, cert, priv); err != nil {
		log.Fatalln(err)
	}
	fmt.Println("Certificate added.")
}