init pseudorandom seed

tools/security/random.go

@@ -4,10 +4,15 @@ import (
 	cryptoRand "crypto/rand"
 	"math/big"
 	mathRand "math/rand"
+	"time"
 )
 
 const defaultRandomAlphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
 
+func init() {
+	mathRand.Seed(time.Now().UnixNano())
+}
+
 // RandomString generates a cryptographically random string with the specified length.
 //
 // The generated string matches [A-Za-z0-9]+ and it's transparent to URL-encoding.