Cold Storage with One-Way RSA Encryption #43
|
@ -204,8 +204,6 @@ func main() {
|
||||||
},
|
},
|
||||||
},
|
},
|
||||||
Action: func(c *cli.Context) error {
|
Action: func(c *cli.Context) error {
|
||||||
initdb(c)
|
|
||||||
|
|
||||||
err := coldstorage.FileFromColdStorage(
|
err := coldstorage.FileFromColdStorage(
|
||||||
c.String("key"),
|
c.String("key"),
|
||||||
c.String("aes"),
|
c.String("aes"),
|
||||||
|
@ -213,7 +211,7 @@ func main() {
|
||||||
c.String("output"),
|
c.String("output"),
|
||||||
)
|
)
|
||||||
if err != nil {
|
if err != nil {
|
||||||
log.Error("Error decrypting from cold storage: %s")
|
log.Error("Error decrypting from cold storage: %s", err)
|
||||||
return err
|
return err
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
70
docs/Cold Storage.md
Normal file
70
docs/Cold Storage.md
Normal file
|
@ -0,0 +1,70 @@
|
||||||
|
# Cold Storage
|
||||||
|
|
||||||
|
One of the security features of the website is **cold storage** which implements a "one way" encryption process for archiving sensitive files on the site.
|
||||||
|
|
||||||
|
The first use case is to archive secondary photo IDs: if a user was requested to provide a scan of their government issued photo ID for approval, the site can archive the original copy to cold storage when approved in case of any future inquiry.
|
||||||
|
|
||||||
|
The cold storage feature works by encrypting the file using an RSA public key, and relies on the matching private key to be **removed** from the web server and kept offline; so in case of a hack or data breach, the key that can decrypt the cold storage files will **NOT** be kept on the same web server.
|
||||||
|
|
||||||
|
This document explains how this feature works and how to configure it.
|
||||||
|
|
||||||
|
## Initialization
|
||||||
|
|
||||||
|
When the server starts up and there is not a cold storage RSA key configured, the feature will be initialized by generating new RSA encryption keys:
|
||||||
|
|
||||||
|
* The directory `./coldstorage/keys` is created and the RSA keys will be written in files named **private.pem** and **public.pem**.
|
||||||
|
* The RSA public key is _also_ written into the **settings.json** file for the server, at the Encryption / ColdStorageRSAPublicKey property.
|
||||||
|
|
||||||
|
You should **move the keys OFF of your web server machine** and keep them safe for your bookkeeping. Notably, the `private.pem` key is the sensitive file that should be removed.
|
||||||
|
|
||||||
|
The app does not need either of these keys to remain on the server: the settings.json has a copy of the RSA public key which the app uses to create cold storage encrypted files.
|
||||||
|
|
||||||
|
### Admin Dashboard Warning
|
||||||
|
|
||||||
|
As a safety precaution: if the private.pem key remains on disk, a warning is shown at the top of the Admin Dashboard page of the website to remind you that the key should be removed and stored safely offline.
|
||||||
|
|
||||||
|
## Recovering from Cold Storage
|
||||||
|
|
||||||
|
Should you need to recover an encrypted file from cold storage, the `nonshy coldstorage decrypt` command built into the Go server binary has the function to decrypt the files.
|
||||||
|
|
||||||
|
Every item that is moved into cold storage generates two files: an encrypted AES key file (`.aes`) and the encrypted data file itself (with a `.enc` extension). For example, a "photo.jpg" might go into cold storage as two files: "photo.jpg.aes" and "photo.jpg.enc"
|
||||||
|
|
||||||
|
You will need the following three files to decrypt from cold storage:
|
||||||
|
|
||||||
|
1. The RSA private key file (private.pem)
|
||||||
|
2. The encrypted AES key file (.aes extension)
|
||||||
|
3. The encrypted cold storage data file (.enc extension)
|
||||||
|
|
||||||
|
The command to decrypt them is thus like:
|
||||||
|
|
||||||
|
```bash
|
||||||
|
# command example
|
||||||
|
nonshy coldstorage decrypt \
|
||||||
|
--key private.pem \
|
||||||
|
--aes photo.jpg.aes \
|
||||||
|
--input photo.jpg.enc \
|
||||||
|
--output photo.jpg
|
||||||
|
|
||||||
|
# short command line flags work too
|
||||||
|
nonshy coldstorage decrypt -k private.pem \
|
||||||
|
-a photo.jpg.aes -i photo.jpg.enc \
|
||||||
|
-o photo.jpg
|
||||||
|
```
|
||||||
|
|
||||||
|
The `--output` file is where the decrypted file will be written to.
|
||||||
|
|
||||||
|
## Encryption Algorithms
|
||||||
|
|
||||||
|
When a file is moved into cold storage:
|
||||||
|
|
||||||
|
1. A fresh new AES symmetric key is generated from scratch.
|
||||||
|
2. The AES key is encrypted using the **RSA public key** and written to the ".aes" file in the coldstorage/ folder.
|
||||||
|
3. The original file is encrypted using that AES symmetric key and written to the ".enc" file in the coldstorage/ folder.
|
||||||
|
|
||||||
|
At the end of the encrypt function: the web server no longer has the AES key and is _unable_ to decrypt it because the private key is not available (as it should be kept offline for security).
|
||||||
|
|
||||||
|
Decrypting a file out of cold storage is done like so:
|
||||||
|
|
||||||
|
1. The encrypted AES key is unlocked using the **RSA private key**.
|
||||||
|
2. The encrypted cold storage file (.enc) is decrypted with that AES key.
|
||||||
|
3. The cleartext data is written to the output file.
|
|
@ -98,7 +98,7 @@ func LoadSettings() {
|
||||||
writeSettings = true
|
writeSettings = true
|
||||||
}
|
}
|
||||||
|
|
||||||
// Initialize the cold storage ECDSA keys.
|
// Initialize the cold storage RSA keys.
|
||||||
if len(Current.Encryption.ColdStorageRSAPublicKey) == 0 {
|
if len(Current.Encryption.ColdStorageRSAPublicKey) == 0 {
|
||||||
x509publicKey, err := coldstorage.Initialize()
|
x509publicKey, err := coldstorage.Initialize()
|
||||||
if err != nil {
|
if err != nil {
|
||||||
|
|
|
@ -472,10 +472,10 @@ func AdminCertification() http.HandlerFunc {
|
||||||
if cert.SecondaryFilename != "" {
|
if cert.SecondaryFilename != "" {
|
||||||
// Move the original photo into cold storage.
|
// Move the original photo into cold storage.
|
||||||
coldStorageFilename := fmt.Sprintf(
|
coldStorageFilename := fmt.Sprintf(
|
||||||
"photoID-%d-%s-%s.jpg",
|
"photoID-%d-%s-%d.jpg",
|
||||||
user.ID,
|
user.ID,
|
||||||
user.Username,
|
user.Username,
|
||||||
time.Now().Format(time.RFC3339Nano),
|
time.Now().Unix(),
|
||||||
)
|
)
|
||||||
if err := coldstorage.FileToColdStorage(
|
if err := coldstorage.FileToColdStorage(
|
||||||
photo.DiskPath(cert.SecondaryFilename),
|
photo.DiskPath(cert.SecondaryFilename),
|
||||||
|
|
72
pkg/encryption/keygen/aes.go
Normal file
72
pkg/encryption/keygen/aes.go
Normal file
|
@ -0,0 +1,72 @@
|
||||||
|
// Package keygen provides the AES key initializer function.
|
||||||
|
package keygen
|
||||||
|
|
||||||
|
import (
|
||||||
|
"crypto/aes"
|
||||||
|
"crypto/cipher"
|
||||||
|
"crypto/rand"
|
||||||
|
"errors"
|
||||||
|
"fmt"
|
||||||
|
"io"
|
||||||
|
)
|
||||||
|
|
||||||
|
// NewAESKey returns a 32-byte (AES 256 bit) encryption key.
|
||||||
|
func NewAESKey() ([]byte, error) {
|
||||||
|
var result = make([]byte, 32)
|
||||||
|
_, err := rand.Read(result)
|
||||||
|
return result, err
|
||||||
|
}
|
||||||
|
|
||||||
|
// EncryptWithAESKey a byte stream using a given AES key.
|
||||||
|
func EncryptWithAESKey(input []byte, key []byte) ([]byte, error) {
|
||||||
|
// Generate a new AES cipher.
|
||||||
|
c, err := aes.NewCipher(key)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
// gcm or Galois/Counter Mode
|
||||||
|
gcm, err := cipher.NewGCM(c)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
// Create a new byte array the size of the GCM nonce
|
||||||
|
// which must be passed to Seal.
|
||||||
|
nonce := make([]byte, gcm.NonceSize())
|
||||||
|
if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
|
||||||
|
return nil, fmt.Errorf("populating the nonce: %s", err)
|
||||||
|
}
|
||||||
|
|
||||||
|
// Encrypt the text using the Seal function.
|
||||||
|
// Seal encrypts and authenticates plaintext, authenticates the
|
||||||
|
// additional data and appends the result to dst, returning the
|
||||||
|
// updated slice. The nonce must be NonceSize() bytes long and
|
||||||
|
// unique for all time, for a given key.
|
||||||
|
result := gcm.Seal(nonce, nonce, input, nil)
|
||||||
|
return result, nil
|
||||||
|
}
|
||||||
|
|
||||||
|
func DecryptWithAESKey(data []byte, key []byte) ([]byte, error) {
|
||||||
|
c, err := aes.NewCipher(key)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
gcm, err := cipher.NewGCM(c)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
nonceSize := gcm.NonceSize()
|
||||||
|
if len(data) < nonceSize {
|
||||||
|
return nil, errors.New("ciphertext data less than nonceSize")
|
||||||
|
}
|
||||||
|
|
||||||
|
nonce, ciphertext := data[:nonceSize], data[nonceSize:]
|
||||||
|
plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
return plaintext, nil
|
||||||
|
}
|
72
pkg/encryption/keygen/aes_test.go
Normal file
72
pkg/encryption/keygen/aes_test.go
Normal file
|
@ -0,0 +1,72 @@
|
||||||
|
package keygen_test
|
||||||
|
|
||||||
|
import (
|
||||||
|
"testing"
|
||||||
|
|
||||||
|
"code.nonshy.com/nonshy/website/pkg/encryption/keygen"
|
||||||
|
)
|
||||||
|
|
||||||
|
func TestAES(t *testing.T) {
|
||||||
|
type testCase struct {
|
||||||
|
AESKey []byte // AES key, nil = generate a new one
|
||||||
|
Input []byte // input text to encrypt
|
||||||
|
Encrypted []byte // already encrypted text
|
||||||
|
Expect []byte // expected output on decrypt
|
||||||
|
}
|
||||||
|
|
||||||
|
var tests = []testCase{
|
||||||
|
{
|
||||||
|
Input: []byte("hello world"),
|
||||||
|
Expect: []byte("hello world"),
|
||||||
|
},
|
||||||
|
{
|
||||||
|
AESKey: []byte{170, 94, 243, 132, 85, 247, 149, 238, 245, 39, 140, 125, 226, 178, 134, 161, 17, 151, 139, 248, 16, 94, 165, 8, 102, 238, 214, 183, 86, 138, 219, 52},
|
||||||
|
Encrypted: []byte{146, 217, 250, 254, 70, 201, 27, 221, 92, 145, 77, 213, 211, 197, 63, 189, 220, 188, 78, 8, 217, 108, 136, 89, 156, 23, 179, 54, 209, 54, 244, 170, 182, 150, 242, 52, 112, 191, 216, 46},
|
||||||
|
Expect: []byte("goodbye mars"),
|
||||||
|
},
|
||||||
|
}
|
||||||
|
|
||||||
|
for i, test := range tests {
|
||||||
|
if len(test.AESKey) == 0 {
|
||||||
|
key, err := keygen.NewAESKey()
|
||||||
|
if err != nil {
|
||||||
|
t.Errorf("Test #%d: failed to generate new AES key: %s", i, err)
|
||||||
|
continue
|
||||||
|
}
|
||||||
|
test.AESKey = key
|
||||||
|
}
|
||||||
|
|
||||||
|
if len(test.Encrypted) == 0 {
|
||||||
|
enc, err := keygen.EncryptWithAESKey(test.Input, test.AESKey)
|
||||||
|
if err != nil {
|
||||||
|
t.Errorf("Test #%d: failed to encrypt input: %s", i, err)
|
||||||
|
continue
|
||||||
|
}
|
||||||
|
test.Encrypted = enc
|
||||||
|
}
|
||||||
|
|
||||||
|
// t.Errorf("Key: %+v\nEnc: %+v", test.AESKey, test.Encrypted)
|
||||||
|
|
||||||
|
dec, err := keygen.DecryptWithAESKey(test.Encrypted, test.AESKey)
|
||||||
|
if err != nil {
|
||||||
|
t.Errorf("Test #%d: failed to decrypt: %s", i, err)
|
||||||
|
continue
|
||||||
|
}
|
||||||
|
|
||||||
|
// compare the results
|
||||||
|
var ok = true
|
||||||
|
if len(dec) != len(test.Expect) {
|
||||||
|
ok = false
|
||||||
|
} else {
|
||||||
|
for j := range dec {
|
||||||
|
if test.Expect[j] != dec[j] {
|
||||||
|
ok = false
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
if !ok {
|
||||||
|
t.Errorf("Test #%d: got unexpected result from decrypt. Expected %s, got %s", i, test.Expect, dec)
|
||||||
|
continue
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
|
@ -3,81 +3,15 @@ package keygen
|
||||||
|
|
||||||
import (
|
import (
|
||||||
"crypto"
|
"crypto"
|
||||||
"crypto/aes"
|
|
||||||
"crypto/cipher"
|
|
||||||
"crypto/rand"
|
"crypto/rand"
|
||||||
"crypto/rsa"
|
"crypto/rsa"
|
||||||
"crypto/x509"
|
"crypto/x509"
|
||||||
"encoding/pem"
|
"encoding/pem"
|
||||||
"errors"
|
|
||||||
"fmt"
|
|
||||||
"io"
|
|
||||||
"os"
|
"os"
|
||||||
|
|
||||||
"code.nonshy.com/nonshy/website/pkg/log"
|
"code.nonshy.com/nonshy/website/pkg/log"
|
||||||
)
|
)
|
||||||
|
|
||||||
// NewAESKey returns a 32-byte (AES 256 bit) encryption key.
|
|
||||||
func NewAESKey() ([]byte, error) {
|
|
||||||
var result = make([]byte, 32)
|
|
||||||
_, err := rand.Read(result)
|
|
||||||
return result, err
|
|
||||||
}
|
|
||||||
|
|
||||||
// EncryptWithAESKey a byte stream using a given AES key.
|
|
||||||
func EncryptWithAESKey(input []byte, key []byte) ([]byte, error) {
|
|
||||||
// Generate a new AES cipher.
|
|
||||||
c, err := aes.NewCipher(key)
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
|
|
||||||
// gcm or Galois/Counter Mode
|
|
||||||
gcm, err := cipher.NewGCM(c)
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
|
|
||||||
// Create a new byte array the size of the GCM nonce
|
|
||||||
// which must be passed to Seal.
|
|
||||||
nonce := make([]byte, gcm.NonceSize())
|
|
||||||
if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
|
|
||||||
return nil, fmt.Errorf("populating the nonce: %s", err)
|
|
||||||
}
|
|
||||||
|
|
||||||
// Encrypt the text using the Seal function.
|
|
||||||
// Seal encrypts and authenticates plaintext, authenticates the
|
|
||||||
// additional data and appends the result to dst, returning the
|
|
||||||
// updated slice. The nonce must be NonceSize() bytes long and
|
|
||||||
// unique for all time, for a given key.
|
|
||||||
result := gcm.Seal(nonce, nonce, input, nil)
|
|
||||||
return result, nil
|
|
||||||
}
|
|
||||||
|
|
||||||
func DecryptWithAESKey(data []byte, key []byte) ([]byte, error) {
|
|
||||||
c, err := aes.NewCipher(key)
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
|
|
||||||
gcm, err := cipher.NewGCM(c)
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
|
|
||||||
nonceSize := gcm.NonceSize()
|
|
||||||
if len(data) < nonceSize {
|
|
||||||
return nil, errors.New("ciphertext data less than nonceSize")
|
|
||||||
}
|
|
||||||
|
|
||||||
nonce, ciphertext := data[:nonceSize], data[nonceSize:]
|
|
||||||
plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
return plaintext, nil
|
|
||||||
}
|
|
||||||
|
|
||||||
// NewRSAKeys will generate an RSA 2048-bit key pair.
|
// NewRSAKeys will generate an RSA 2048-bit key pair.
|
||||||
func NewRSAKeys() (*rsa.PrivateKey, error) {
|
func NewRSAKeys() (*rsa.PrivateKey, error) {
|
||||||
privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
|
privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
|
Loading…
Reference in New Issue
Block a user