blueprint: add support for unencrypted passwords in user customization

internal/crypt/crypt.go

@@ -0,0 +1,49 @@
+package crypt
+
+import (
+	"crypto/rand"
+	"math/big"
+	"strings"
+)
+
+func CryptSHA512(phrase string) (string, error) {
+	const SHA512SaltLength = 16
+
+	salt, err := genSalt(SHA512SaltLength)
+
+	if err != nil {
+		return "", nil
+	}
+
+	hashSettings := "$6$" + salt
+	return crypt(phrase, hashSettings)
+}
+
+func genSalt(length int) (string, error) {
+	saltChars := "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789./"
+
+	b := make([]byte, length)
+
+	for i := range b {
+		runeIndex, err := rand.Int(rand.Reader, big.NewInt(int64(len(saltChars))))
+		if err != nil {
+			return "", err
+		}
+		b[i] = saltChars[runeIndex.Int64()]
+	}
+
+	return string(b), nil
+}
+
+func PasswordIsCrypted(s string) bool {
+	// taken from lorax src: src/pylorax/api/compose.py:533
+	prefixes := [...]string{"$2b$", "$6$", "$5$"}
+
+	for _, prefix := range prefixes {
+		if strings.HasPrefix(s, prefix) {
+			return true
+		}
+	}
+
+	return false
+}