Major Update, registration and authentication of devices works now.

This is the first iteration of the registration of devices and authentication for a couple of endpoints.
This needs to be refactored, the code is a bit of a mess. Also because of testing some endpoints are available for remotes that shouldn't be.

be/app/helper/encrypt-helper.go

@@ -0,0 +1,105 @@
+package helper
+
+import (
+	"bytes"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/base64"
+	"errors"
+	"strings"
+)
+
+func EncryptAES(key string, plaintext string) (string, error) {
+	origData := []byte(plaintext)
+
+	// Create AES cipher
+	block, err := aes.NewCipher(keyToBytes(key))
+	if err != nil {
+		return "", err
+	}
+	blockSize := block.BlockSize()
+
+	origData = PKCS5Padding(origData, blockSize)
+
+	iv := []byte(EnvGet("MCRM__IV"))
+	blockMode := cipher.NewCBCEncrypter(block, iv)
+
+	crypted := make([]byte, len(origData))
+	blockMode.CryptBlocks(crypted, origData)
+
+	cryptedString := base64.StdEncoding.EncodeToString(crypted)
+
+	return cryptedString, nil
+}
+
+func DecryptAES(key string, cryptedText string) (string, error) {
+	crypted, err := base64.StdEncoding.DecodeString(cryptedText)
+
+	if err != nil {
+		return "", err
+	}
+
+	block, err := aes.NewCipher(keyToBytes(key))
+	if err != nil {
+		return "", err
+	}
+
+	iv := []byte(EnvGet("MCRM__IV"))
+	blockMode := cipher.NewCBCDecrypter(block, iv)
+
+	origData := make([]byte, len(crypted))
+
+	blockMode.CryptBlocks(origData, crypted)
+	origData, err = PKCS5UnPadding(origData)
+
+	if err != nil || len(origData) <= 3 {
+		return "", errors.New("invalid key")
+	}
+
+	origDataString := string(origData)
+
+	return origDataString, nil
+}
+
+func generateRandomString(length int) string {
+	b := make([]byte, length)
+	_, err := rand.Read(b)
+	if err != nil {
+		panic(err)
+	}
+	return base64.StdEncoding.EncodeToString(b)
+}
+
+func GenerateKey() string {
+	return strings.Replace(generateRandomString(24), "=", "", -1)
+}
+
+func keyToBytes(key string) []byte {
+	// Convert key to bytes
+	keyBytes := []byte(key)
+
+	// If key is 4 characters, append salt
+	if len(key) == 4 {
+		keyBytes = []byte(key + EnvGet("MCRM__SALT"))
+	}
+
+	return keyBytes
+}
+
+func PKCS5Padding(ciphertext []byte, blockSize int) []byte {
+	padding := blockSize - len(ciphertext)%blockSize
+	padtext := bytes.Repeat([]byte{byte(padding)}, padding)
+	return append(ciphertext, padtext...)
+}
+
+func PKCS5UnPadding(origData []byte) ([]byte, error) {
+	length := len(origData)
+	unpadding := int(origData[length-1])
+
+	if (unpadding >= length) || (unpadding == 0) {
+		return nil, errors.New("unpadding error")
+	}
+
+	return origData[:(length - unpadding)], nil
+}