summaryrefslogtreecommitdiff
path: root/pkg/vpn/launcher.go
blob: 1b2d67353c03b20f68cbf9afbff40e842d243185 (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
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
168
// +build !linux
// Copyright (C) 2018-2020 LEAP
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package vpn

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"io/ioutil"
	"log"
	"net/http"
	"strconv"
	"strings"
	"time"

	"0xacab.org/leap/bitmask-vpn/pkg/config"
	"0xacab.org/leap/bitmask-vpn/pkg/vpn/bonafide"
)

type launcher struct {
	helperAddr string
	failed     bool
}

const initialHelperPort = 7171

func probeHelperPort(port int) int {
	// this should be enough for a local reply
	timeout := time.Duration(500 * time.Millisecond)
	c := http.Client{Timeout: timeout}
	for {
		if smellsLikeOurHelperSpirit(port, &c) {
			return port
		}
		port++
		/* we could go until 65k, but there's really no need */
		if port > 10000 {
			break
		}
	}
	log.Println("WARN: Cannot find any working helper")
	return 0
}

func smellsLikeOurHelperSpirit(port int, c *http.Client) bool {
	uri := "http://localhost:" + strconv.Itoa(port) + "/version"
	resp, err := c.Get(uri)
	if err != nil {
		return false
	}
	if resp.StatusCode == 200 {
		ver, err := ioutil.ReadAll(resp.Body)
		defer resp.Body.Close()
		if err != nil {
			return false
		}
		if strings.Contains(string(ver), config.ApplicationName) {
			log.Println("DEBUG: Successfully probed for matching helper at", uri)
			return true
		} else {
			log.Println("DEBUG: Another helper seems to be running:", string(ver))
			log.Println("DEBUG: But we were hoping to find:", config.ApplicationName)
		}
	}
	return false
}

func newLauncher() (*launcher, error) {
	helperPort := probeHelperPort(initialHelperPort)
	helperAddr := "http://localhost:" + strconv.Itoa(helperPort)
	return &launcher{helperAddr, false}, nil
}

func (l *launcher) close() error {
	return nil
}

func (l *launcher) check() (helpers bool, priviledge bool, err error) {
	return true, true, nil
}

func (l *launcher) openvpnStart(flags ...string) error {
	byteFlags, err := json.Marshal(flags)
	if err != nil {
		return err
	}
	return l.send("/openvpn/start", byteFlags)
}

func (l *launcher) openvpnStop() error {
	return l.send("/openvpn/stop", nil)
}

func (l *launcher) firewallStart(gateways []bonafide.Gateway) error {
	ipList := make([]string, len(gateways))
	for i, gw := range gateways {
		ipList[i] = gw.IPAddress
	}
	byteIPs, err := json.Marshal(ipList)
	if err != nil {
		return err
	}
	return l.send("/firewall/start", byteIPs)
}

func (l *launcher) firewallStop() error {
	return l.send("/firewall/stop", nil)
}

func (l *launcher) firewallIsUp() bool {
	var isup bool = false
	res, err := http.Post(l.helperAddr+"/firewall/isup", "", nil)
	if err != nil {
		return false
	}
	defer res.Body.Close()

	if res.StatusCode != http.StatusOK {
		fmt.Printf("Got an error status code for firewall/isup: %v\n", res.StatusCode)
		isup = false
	} else {
		upStr, err := ioutil.ReadAll(res.Body)
		if err != nil {
			fmt.Errorf("Error getting body for firewall/isup: %q", err)
			return false
		}
		isup, err = strconv.ParseBool(string(upStr))
		if err != nil {
			fmt.Errorf("Error parsing body for firewall/isup: %q", err)
			return false
		}
	}
	return isup
}

func (l *launcher) send(path string, body []byte) error {
	var reader io.Reader
	if body != nil {
		reader = bytes.NewReader(body)
	}
	res, err := http.Post(l.helperAddr+path, "", reader)
	if err != nil {
		return err
	}
	defer res.Body.Close()

	resErr, err := ioutil.ReadAll(res.Body)
	if len(resErr) > 0 {
		/* FIXME why do we trigger a fatal with this error? */
		return fmt.Errorf("FATAL: Helper returned an error: %q", resErr)
	}
	return err
}