Add vendor (steam)

1 files changed, 38 insertions, 0 deletions

diff --git a/vendor/github.com/Philipp15b/go-steam/cryptoutil/cryptoutil.go b/vendor/github.com/Philipp15b/go-steam/cryptoutil/cryptoutil.go
new file mode 100644
index 00000000..b44f8d26
--- /dev/null
+++ b/vendor/github.com/Philipp15b/go-steam/cryptoutil/cryptoutil.go
@@ -0,0 +1,38 @@
+package cryptoutil

+

+import (

+	"crypto/aes"

+	"crypto/cipher"

+	"crypto/rand"

+)

+

+// Performs an encryption using AES/CBC/PKCS7

+// with a random IV prepended using AES/ECB/None.

+func SymmetricEncrypt(ciph cipher.Block, src []byte) []byte {

+	// get a random IV and ECB encrypt it

+	iv := make([]byte, aes.BlockSize, aes.BlockSize)

+	_, err := rand.Read(iv)

+	if err != nil {

+		panic(err)

+	}

+	encryptedIv := make([]byte, aes.BlockSize, aes.BlockSize)

+	newECBEncrypter(ciph).CryptBlocks(encryptedIv, iv)

+

+	// pad it, copy the IV to the first 16 bytes and encrypt the rest with CBC

+	encrypted := padPKCS7WithIV(src)

+	copy(encrypted, encryptedIv)

+	cipher.NewCBCEncrypter(ciph, iv).CryptBlocks(encrypted[aes.BlockSize:], encrypted[aes.BlockSize:])

+	return encrypted

+}

+

+// Decrypts data from the reader using AES/CBC/PKCS7 with an IV

+// prepended using AES/ECB/None. The src slice may not be used anymore.

+func SymmetricDecrypt(ciph cipher.Block, src []byte) []byte {

+	iv := src[:aes.BlockSize]

+	newECBDecrypter(ciph).CryptBlocks(iv, iv)

+

+	data := src[aes.BlockSize:]

+	cipher.NewCBCDecrypter(ciph, iv).CryptBlocks(data, data)

+

+	return unpadPKCS7(data)

+}