Method random

security/src/main/java/pro/tools/security/sm/SM2.java:68–74

随机数生成器 @param max @return

(BigInteger max)

     * @return
     */
    private static BigInteger random(BigInteger max) {
        BigInteger r = new BigInteger(256, random);
        while (r.compareTo(max) >= 0) {
            r = new BigInteger(128, random);
        }
        return r;
    }

    /**
     * 字节数组拼接