Fix #296 (Cyberghost implementation) (#297)

* Reads the client key from /gluetun/client.key
* Read the client certificate from /gluetun/client.crt
* Additional checks for client key and client certificate validity
* Fix client key file parsing if environment variable isn't present

.golangci.yml

@@ -4,6 +4,13 @@ linters-settings:
   misspell:
     locale: US
 
+issues:
+  exclude-rules:
+    - path: _test\.go
+      linters:
+        - dupl
+        - maligned
+
 linters:
   disable-all: true
   enable:
@@ -57,4 +64,4 @@ run:
   skip-dirs:
     - .devcontainer
     - .github
-    - postgres
+    - doc

README.md

@@ -159,20 +159,15 @@ docker run --rm --network=container:gluetun alpine:3.12 wget -qO- https://ipinfo
     | --- | --- | --- | --- |
     | 🏁 `USER` | | | Your username |
     | 🏁 `PASSWORD` | | | Your password |
-    | 🏁 `CLIENT_KEY` | | | Your device client key content, **see below** |
+    | 🏁 | | | **See additional setup steps below** |
     | `REGION` | | One of the Cyberghost regions, [Wiki page](https://github.com/qdm12/gluetun/wiki/Cyberghost-Servers) | VPN server country |
     | `CYBERGHOST_GROUP` | `Premium UDP Europe` | One of the server groups (see above Wiki page) | Server group |
 
-    To specify your client key, you can either:
+    **Additional setup steps**: Bind mount your `client.key` file to `/gluetun/client.key` and your `client.crt` file to `/gluetun/client.crt`. For example, you can use with your `docker run` command:
 
-    - Bind mount it at `/files/client.key`, for example with `-v /yourpath/client.key:/files/client.key:ro`
-    - Convert it to a single line value using:
-
-        ```sh
-        docker run -it --rm -v /yourpath/client.key:/files/client.key:ro qmcgaw/private-internet-access clientkey
-        ```
-
-        And use the line produced as the value for the environment variable `CLIENT_KEY`.
+    ```sh
+    -v /yourpath/client.key:/gluetun/client.key:ro -v /yourpath/client.crt:/gluetun/client.crt:ro
+    ```
 
 - Vyprvpn
 

internal/cli/cli.go

@@ -21,7 +21,7 @@ import (
 
 func ClientKey(args []string) error {
 	flagSet := flag.NewFlagSet("clientkey", flag.ExitOnError)
-	filepath := flagSet.String("path", "/files/client.key", "file path to the client.key file")
+	filepath := flagSet.String("path", string(constants.ClientKey), "file path to the client.key file")
 	if err := flagSet.Parse(args); err != nil {
 		return err
 	}

internal/constants/cyberghost.go

@@ -9,8 +9,7 @@ import (
 
 //nolint:lll
 const (
-	CyberghostCertificate       = "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"
-	CyberghostClientCertificate = "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"
+	CyberghostCertificate = "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"
 )
 
 func CyberghostRegionChoices() (choices []string) {

internal/constants/paths.go

@@ -25,4 +25,8 @@ const (
 	RootHints models.Filepath = "/etc/unbound/root.hints"
 	// RootKey is the filepath to the root.key file used by Unbound.
 	RootKey models.Filepath = "/etc/unbound/root.key"
+	// Client key filepath, used by Cyberghost.
+	ClientKey models.Filepath = "/gluetun/client.key"
+	// Client certificate filepath, used by Cyberghost.
+	ClientCertificate models.Filepath = "/gluetun/client.crt"
 )

internal/models/selection.go

@@ -44,9 +44,10 @@ type ServerSelection struct {
 }
 
 type ExtraConfigOptions struct {
-	ClientKey        string `json:"-"`                // Cyberghost
-	EncryptionPreset string `json:"encryptionPreset"` // PIA
-	OpenVPNIPv6      bool   `json:"openvpnIPv6"`      // Mullvad
+	ClientCertificate string `json:"-"`                // Cyberghost
+	ClientKey         string `json:"-"`                // Cyberghost
+	EncryptionPreset  string `json:"encryptionPreset"` // PIA
+	OpenVPNIPv6       bool   `json:"openvpnIPv6"`      // Mullvad
 }
 
 // PortForwarding contains settings for port forwarding.
@@ -111,7 +112,8 @@ func (p *ProviderSettings) String() string {
 		)
 	case "cyberghost":
 		settingsList = append(settingsList,
-			"ClientKey: [redacted]",
+			"Client key: [redacted]",
+			"Client certificate: [redacted]",
 			"Group: "+p.ServerSelection.Group,
 			"Regions: "+commaJoin(p.ServerSelection.Regions),
 		)

internal/params/cyberghost.go

@@ -1,6 +1,8 @@
 package params
 
 import (
+	"encoding/pem"
+	"fmt"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/constants"
@@ -22,20 +24,53 @@ func (p *reader) GetCyberghostRegions() (regions []string, err error) {
 }
 
 // GetCyberghostClientKey obtains the one line client key to use for openvpn from the
-// environment variable CLIENT_KEY.
+// environment variable CLIENT_KEY or from the file at /gluetun/client.key.
 func (p *reader) GetCyberghostClientKey() (clientKey string, err error) {
 	clientKey, err = p.envParams.GetEnv("CLIENT_KEY", libparams.CaseSensitiveValue())
 	if err != nil {
 		return "", err
 	} else if len(clientKey) > 0 {
 		return clientKey, nil
 	}
-	content, err := p.fileManager.ReadFile("/files/client.key")
+	content, err := p.fileManager.ReadFile(string(constants.ClientKey))
 	if err != nil {
 		return "", err
 	}
-	s := string(content)
+	return extractClientKey(content)
+}
+
+func extractClientKey(b []byte) (key string, err error) {
+	pemBlock, _ := pem.Decode(b)
+	if pemBlock == nil {
+		return "", fmt.Errorf("cannot decode PEM block from client key")
+	}
+	parsedBytes := pem.EncodeToMemory(pemBlock)
+	s := string(parsedBytes)
+	s = strings.ReplaceAll(s, "\n", "")
+	s = strings.TrimPrefix(s, "-----BEGIN PRIVATE KEY-----")
+	s = strings.TrimSuffix(s, "-----END PRIVATE KEY-----")
+	return s, nil
+}
+
+// GetCyberghostClientCertificate obtains the client certificate to use for openvpn from the
+// file at /gluetun/client.crt.
+func (p *reader) GetCyberghostClientCertificate() (clientCertificate string, err error) {
+	content, err := p.fileManager.ReadFile(string(constants.ClientCertificate))
+	if err != nil {
+		return "", err
+	}
+	return extractClientCertificate(content)
+}
+
+func extractClientCertificate(b []byte) (certificate string, err error) {
+	pemBlock, _ := pem.Decode(b)
+	if pemBlock == nil {
+		return "", fmt.Errorf("cannot decode PEM block from client certificate")
+	}
+	parsedBytes := pem.EncodeToMemory(pemBlock)
+	s := string(parsedBytes)
 	s = strings.ReplaceAll(s, "\n", "")
-	s = strings.ReplaceAll(s, "\r", "")
+	s = strings.TrimPrefix(s, "-----BEGIN CERTIFICATE-----")
+	s = strings.TrimSuffix(s, "-----END CERTIFICATE-----")
 	return s, nil
 }