terraform-provider/internal/client/helpers.go

package kmsclient

import (
	"encoding/base64"
	"errors"
	"fmt"
	"strings"
)

type DecodedSymmetricEncryptionDetails = struct {
	Cipher []byte
	IV     []byte
	Tag    []byte
	Key    []byte
}

// Define a generic not found error type.
type NotFoundError struct {
	Resource string
	ID       string
}

func GetBase64DecodedSymmetricEncryptionDetails(key string, cipher string, IV string, tag string) (DecodedSymmetricEncryptionDetails, error) {
	cipherx, err := base64.StdEncoding.DecodeString(cipher)
	if err != nil {
		return DecodedSymmetricEncryptionDetails{}, fmt.Errorf("Base64DecodeSymmetricEncryptionDetails: Unable to decode cipher text [err=%v]", err)
	}

	keyx, err := base64.StdEncoding.DecodeString(key)
	if err != nil {
		return DecodedSymmetricEncryptionDetails{}, fmt.Errorf("Base64DecodeSymmetricEncryptionDetails: Unable to decode key [err=%v]", err)
	}

	IVx, err := base64.StdEncoding.DecodeString(IV)
	if err != nil {
		return DecodedSymmetricEncryptionDetails{}, fmt.Errorf("Base64DecodeSymmetricEncryptionDetails: Unable to decode IV [err=%v]", err)
	}

	tagx, err := base64.StdEncoding.DecodeString(tag)
	if err != nil {
		return DecodedSymmetricEncryptionDetails{}, fmt.Errorf("Base64DecodeSymmetricEncryptionDetails: Unable to decode tag [err=%v]", err)
	}

	return DecodedSymmetricEncryptionDetails{
		Key:    keyx,
		Cipher: cipherx,
		IV:     IVx,
		Tag:    tagx,
	}, nil
}

func GetSymmetricKeyFromServiceToken(serviceToken string) (privateKey string, err error) {
	serviceTokenParts := strings.SplitN(serviceToken, ".", 4)
	if len(serviceTokenParts) < 4 {
		return "", errors.New("invalid service token entered. Please double check your service token and try again")
	}

	return serviceTokenParts[3], nil
}

func (e *NotFoundError) Error() string {
	return fmt.Sprintf("%s with ID %s not found", e.Resource, e.ID)
}

// A helper function to create a new NotFoundError.
func NewNotFoundError(resource, id string) error {
	return &NotFoundError{
		Resource: resource,
		ID:       id,
	}
}