Hex+aes (#71)

Author: scr-oath

crypto/README.md

@@ -3,15 +3,22 @@
 ## Functions
 - `md5(string)` - return md5 checksum from string.
 - `sha256(string)` - return sha256 checksum from string.
-- `aes_encrypt(string, string, string, string)` - return AES encrypted hex-encoded ciphertext
-- `aes_decrypt(string, string, string, string)` - return AES decrypted hex-encoded plain text
+- `aes_encrypt(string, string, string, string)` - return AES encrypted binary ciphertext
+- `aes_decrypt(string, string, string, string)` - return AES decrypted binary text
+- `aes_encrypt_hex(string, string, string, string)` - return AES encrypted hex-encoded ciphertext
+- `aes_decrypt_hex(string, string, string, string)` - return AES decrypted hex-encoded plain text
 
-AES support 3 modes: GCM, CBC, and CTR - first parameter is mode, second is hex-encoded key, third is hex-encoded initialization vector or nonce - depending on the mode, and forth is hex-encoded plain text or ciphertext.
+AES support 3 modes: GCM, CBC, and CTR - first parameter is mode, second is hex-encoded key, third is hex-encoded
+initialization vector or nonce - depending on the mode, and forth is hex-encoded plain text or ciphertext.
+
+Since lua strings are binary safe, you can use any binary data as input and output and, for your convenience, the
+library also provides hex-encoded versions of the encrypt and decrypt functions. The first argument (the mode string)
+can be one of the following: "GCM", "CBC", or "CTR" (case-insensitive) and is not hex-encoded for the hex variants.
 
 ## Examples
 
 ```lua
-local crypto = require("crypto")
+local crypto = require 'crypto'
 
 -- md5
 if not(crypto.md5("1\n") == "b026324c6904b2a9cb4b88d6d61c81d1") then
@@ -23,18 +30,46 @@ if not(crypto.sha256("1\n") == "4355a46b19d348dc2f57c046f8ef63d4538ebb936000f3c9
     error("sha256")
 end
 
---- aes encrypt in GCM mode
-s, err = crypto.aes_encrypt(1, "86e15cbc1cbf510d8f2e51d4b63a2144", "b6b86d581a991a652158bd10", "48656c6c6f20776f726c64")
+--- aes encrypt in GCM mode with hex-encoded data
+s, err = crypto.aes_encrypt_hex(crypto.GCM, "86e15cbc1cbf510d8f2e51d4b63a2144", "b6b86d581a991a652158bd10", "48656c6c6f20776f726c64")
+assert(not err, err)
 if not(s == "7ec4e38508a26abf7b46e8dc90a7299d5144bcf045e460c3ef6b3e") then
     error("encrypt AES")
 end
-assert(not err, err)
 
---- aes decrypt in GCM mode
-s, err = crypto.aes_decrypt(1, "86e15cbc1cbf510d8f2e51d4b63a2144", "b6b86d581a991a652158bd10", "7ec4e38508a26abf7b46e8dc90a7299d5144bcf045e460c3ef6b3e")
+--- aes decrypt in GCM mode with hex-encoded data
+s, err = crypto.aes_decrypt_hex(crypto.GCM, "86e15cbc1cbf510d8f2e51d4b63a2144", "b6b86d581a991a652158bd10", "7ec4e38508a26abf7b46e8dc90a7299d5144bcf045e460c3ef6b3e")
+assert(not err, err)
 if not(s == "48656c6c6f20776f726c64") then
-    error("decrypt AES)
+    error("decrypt AES")
+end
+
+--- Binary examples setup of binary strings equivalent to the hex-encoded strings above:
+local hex = require 'hex'
+local key, iv, plaintext, encrypted, err
+key, err = hex.decode_string('86e15cbc1cbf510d8f2e51d4b63a2144')
+assert(not err, err)
+iv, err = hex.decode_string('b6b86d581a991a652158bd10')
+assert(not err, err)
+plaintext, err = hex.decode_string('48656c6c6f20776f726c64')
+assert(not err, err)
+s, err = crypto.aes_encrypt(crypto.GCM, key, iv, plaintext)
+assert(not err, err)
+encrypted, err = hex.decode_string("7ec4e38508a26abf7b46e8dc90a7299d5144bcf045e460c3ef6b3e")
+assert(not err, err)
+
+--- aes encrypt binary in GCM mode
+s, err = crypto.aes_encrypt(crypto.GCM, key, iv, plaintext)
+assert(not err, err)
+if not(s == encrypted) then
+    error("encrypt AES")
 end
+
+--- aes decrypt in GCM mode
+s, err = crypto.aes_decrypt(crypto.GCM, key, iv, encrypted)
 assert(not err, err)
+if not(s == plaintext) then
+    error("decrypt AES")
+end
 
 ```

crypto/api.go

@@ -28,6 +28,26 @@ func SHA256(L *lua.LState) int {
 
 // AESEncrypt implements AES encryption in Lua.
 func AESEncrypt(l *lua.LState) int {
+	modeStr := l.CheckString(1)
+	m, err := parseString(modeStr)
+	if err != nil {
+		l.ArgError(1, err.Error())
+	}
+	key := []byte(l.CheckString(2))
+	iv := []byte(l.CheckString(3))
+	data := []byte(l.CheckString(4))
+	enc, err := encryptAES(m, key, iv, data)
+	if err != nil {
+		l.Push(lua.LNil)
+		l.Push(lua.LString(fmt.Sprintf("failed to encrypt: %v", err)))
+		return 2
+	}
+	l.Push(lua.LString(enc))
+	return 1
+}
+
+// AESEncryptHex implements AES encryption in Lua.
+func AESEncryptHex(l *lua.LState) int {
 	m, key, iv, data, err := decodeParams(l)
 	if err != nil {
 		l.Push(lua.LNil)
@@ -47,6 +67,26 @@ func AESEncrypt(l *lua.LState) int {
 
 // AESDecrypt implement AES decryption in Lua.
 func AESDecrypt(l *lua.LState) int {
+	modeStr := l.CheckString(1)
+	m, err := parseString(modeStr)
+	if err != nil {
+		l.ArgError(1, err.Error())
+	}
+	key := []byte(l.CheckString(2))
+	iv := []byte(l.CheckString(3))
+	data := []byte(l.CheckString(4))
+	dec, err := decryptAES(m, key, iv, data)
+	if err != nil {
+		l.Push(lua.LNil)
+		l.Push(lua.LString(fmt.Sprintf("failed to decrypt: %v", err)))
+		return 2
+	}
+	l.Push(lua.LString(dec))
+	return 1
+}
+
+// AESDecryptHex implement AES decryption in Lua.
+func AESDecryptHex(l *lua.LState) int {
 	m, key, iv, data, err := decodeParams(l)
 	if err != nil {
 		l.Push(lua.LNil)

crypto/api_test.go

@@ -4,10 +4,18 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/vadv/gopher-lua-libs/filepath"
+	"github.com/vadv/gopher-lua-libs/hex"
+	"github.com/vadv/gopher-lua-libs/ioutil"
 	"github.com/vadv/gopher-lua-libs/tests"
 )
 
 func TestApi(t *testing.T) {
-	preload := tests.SeveralPreloadFuncs(Preload)
+	preload := tests.SeveralPreloadFuncs(
+		Preload,
+		filepath.Preload,
+		hex.Preload,
+		ioutil.Preload,
+	)
 	assert.NotZero(t, tests.RunLuaTestFile(t, preload, "./test/test_api.lua"))
 }

crypto/loader.go

@@ -13,14 +13,20 @@ func Preload(L *lua.LState) {
 // Loader is the module loader function.
 func Loader(L *lua.LState) int {
 	t := L.NewTable()
+	// Load the constants
+	for name := range modeNames {
+		t.RawSetString(name, lua.LString(name))
+	}
 	L.SetFuncs(t, api)
 	L.Push(t)
 	return 1
 }
 
 var api = map[string]lua.LGFunction{
-	"md5":         MD5,
-	"sha256":      SHA256,
-	"aes_encrypt": AESEncrypt,
-	"aes_decrypt": AESDecrypt,
+	"md5":             MD5,
+	"sha256":          SHA256,
+	"aes_encrypt_hex": AESEncryptHex,
+	"aes_decrypt_hex": AESDecryptHex,
+	"aes_encrypt":     AESEncrypt,
+	"aes_decrypt":     AESDecrypt,
 }

crypto/test/data/1.data.bin

@@ -0,0 +1 @@
+Hello world

crypto/test/data/1.expected.bin

@@ -0,0 +1 @@
+�4������

crypto/test/data/1.init.bin

@@ -0,0 +1 @@
+�¿:	������

crypto/test/data/1.key.bin

@@ -0,0 +1 @@
+��\��Q�.QԶ:!D