1 files changed, 35 insertions, 0 deletions
diff --git a/internal/users/sessionids.go b/internal/users/sessionids.go
new file mode 100644
index 0000000..9b0d59b
--- /dev/null
+++ b/internal/users/sessionids.go
@@ -0,0 +1,35 @@
+package users
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/hex"
+)
+
+const SessionPrefix string = "rpu_"
+
+// generates an random id for session unique identifier
+func GenID(byteSize int) string {
+	id := make([]byte, byteSize)
+	_, err := rand.Read(id) // this is never supposed to error apparently
+	if err != nil {
+		return ""
+	}
+	fmtID := hex.EncodeToString(id)
+	return fmtID
+}
+
+// hash using sha256
+func HashSID(sid string) string {
+	h := sha256.New()
+	h.Write([]byte(sid))
+	hb := h.Sum(nil)
+	hs := hex.EncodeToString(hb)
+	return hs
+}
+
+// verify integrity of sid against database sid
+func VerifySID(sid string, dbsid string) bool {
+	n := HashSID(sid)
+	return n == dbsid
+}