1 files changed, 55 insertions, 0 deletions
diff --git a/src/user/secret.go b/src/user/secret.go
new file mode 100644
index 0000000..55b8bc6
--- /dev/null
+++ b/src/user/secret.go
@@ -0,0 +1,55 @@
+package user
+
+import (
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+
+	"golang.org/x/crypto/argon2"
+)
+
+type Secret struct {
+	Raw  string
+	hash string
+}
+
+func (s Secret) HashSecret() error {
+	hashconf := &struct {
+		memory      uint32
+		iterations  uint32
+		parallelism uint8
+		keyLength   uint32
+		saltLength  uint32
+	}{64 * 1024, 3, 2, 12, 16}
+	salt := make([]byte, hashconf.saltLength)
+	_, err := rand.Read(salt)
+	if err != nil {
+		return err
+	}
+
+	hash := argon2.IDKey(
+		[]byte(s.Raw),
+		salt,
+		hashconf.iterations,
+		hashconf.memory,
+		hashconf.parallelism,
+		hashconf.keyLength,
+	)
+	b64Salt := base64.RawStdEncoding.EncodeToString(salt)
+	b64Hash := base64.RawStdEncoding.EncodeToString(hash)
+	encodedHash := fmt.Sprintf(
+		"$argon2id$v=%d$m=%d,t=%d,p=%d$%s$%s",
+		argon2.Version,
+		hashconf.memory,
+		hashconf.iterations,
+		hashconf.parallelism,
+		b64Salt,
+		b64Hash,
+	)
+	s.hash = encodedHash
+	return err
+}
+
+func (s *Secret) Hash() string {
+	return s.hash
+}