Encryption SDKs for Go

Overview · Core · Identity · Other platforms · Contributing · License

Overview

Tanker is an open-source solution to protect sensitive data in any application, with a simple end-user experience and good performance. No cryptographic skills are required to implement it.

Tanker Core

Tanker Core is the foundation, it provides powerful end-to-end encryption of any type of data, textual or binary. Tanker Core handles multi-device, identity verification, user groups and pre-registration sharing.

Tanker Core usage example

The Core SDK takes care of all the difficult cryptography in the background, leaving you with simple high-level APIs. The Core SDK automatically handles complex key exchanges, cryptographic operations, and identity verification for you.

You can copy/paste the following example:

package main

import (
	"encoding/base64"
	"encoding/json"
	"fmt"
	"log"
	"io/ioutil"
	"net/http"
	"os"

	"github.com/TankerHQ/sdk-go/v2/core"
)

const (
	AppID   = <your app id>
	AppURL  = "https://api.tanker.io"
	AuthURL = "https://fakeauth.tanker.io"
)

func base64ToUrlBase64(param string) (res string, err error) {
	bin, err := base64.StdEncoding.DecodeString(param)
	if err != nil {
		return
	}
	res = base64.URLEncoding.EncodeToString(bin)
	return
}

func GetIdentity() (identity string, err error) {
	urlAppID, err := base64ToUrlBase64(AppID)
	if err != nil {
		return
	}
	resp, err := http.Get(fmt.Sprintf("%s/apps/%s/disposable_private_identity", AuthURL, urlAppID))
	if err != nil {
		return
	}
	if resp.StatusCode != 200 {
		err = fmt.Errorf("Cannot fetch identity from server '%s'", resp.Status)
		return
	}
	defer resp.Body.Close()
	bin, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return
	}
	var res map[string]string
	if err = json.Unmarshal(bin, &res); err != nil {
		return
	}
	if len(res["code"]) != 0 {
		err = fmt.Errorf("Failed to retrieve identity '%s', '%s'", res["code"], res["message"])
		return
	}
	identity = res["private_permanent_identity"]
	return
}

func main() {
	fmt.Println("Creating tanker ...")
	tankerOpts := core.TankerOptions{AppID: AppID, WritablePath: os.TempDir()}
	tanker, err := core.NewTanker(tankerOpts)
	if err != nil {
		log.Fatal("Could not create Tanker", err)
	}
	core.SetLogHandler(func(core.LogRecord) {})
	fmt.Println("Fetching identity ...")
	aliceIdentity, err := GetIdentity()
	if err != nil {
		log.Fatal("Could not get identity")
		return
	}

	fmt.Println("Starting tanker ...")
	status, err := tanker.Start(string(aliceIdentity))
	if err != nil {
		log.Fatal("Could not start tanker", err)
	}
	switch status {
	case core.StatusIdentityVerificationNeeded:
		err = tanker.VerifyIdentity(core.PassphraseVerification{"*******"})
	case core.StatusIdentityRegistrationNeeded:
		err = tanker.RegisterIdentity(core.PassphraseVerification{"*******"})
	}
	if err != nil {
		log.Fatal("Could not register identity:", err)
	}

	message := "This is my story"
	fmt.Println("Encrypting message ...")
	encrypted, err := tanker.Encrypt([]byte(message), nil)
	if err != nil {
		log.Fatal("Failed to encrypt message", err)
	}

	fmt.Println("Decrypting message ...")
	clearBytes, err := tanker.Decrypt(encrypted)
	if err != nil {
		log.Fatal("Failed to decrypt  message", err)
	}

	if clearText != message {
		log.Fatal("Unexpected decrypted message: got '%s', want '%s'", clearText, message)
	}

	fmt.Println("Success!")
}

Before running it, set the AppID with the one you have created on your dashboard. You MUST enable the test mode for this example to work.

Then:

go build -o example-go && ./example-go

For more details and advanced examples, please refer to:

• Core SDK implementation guide
• Core API reference

Identity management

End-to-end encryption requires that all users have cryptographic identities. The following packages help to handle them:

Tanker Identity is a server side package to link Tanker identities with your users in your application backend. It is available in multiple languages. Check identity-go for more details, other implementation exists for different language.

Contributing

We welcome feedback, bug reports, and bug fixes in the form of pull requests.

Other platforms

Tanker is also available for your mobile applications: use our open-source iOS and Android SDKs.

License

The Tanker Golang SDK is licensed under the Apache License, version 2.0.