csharp/alexrainman/ModernHttpClient/ModernHttpClient.Android/Utility.cs

using System;
using System.Globalization;
using System.Net.Http;

namespace ModernHttpClient
{
    internal static clast Utility
    {
        public static bool MatchHostnameToPattern(string hostname, string pattern)
        {
            // check if this is a pattern
            int index = pattern.IndexOf('*');
            if (index == -1)
            {
                // not a pattern, do a direct case-insensitive comparison
                return (string.Compare(hostname, pattern, StringComparison.OrdinalIgnoreCase) == 0);
            }

            // check pattern validity
            // A "*" wildcard character MAY be used as the left-most name component in the certificate.

            // unless this is the last char (valid)
            if (index != pattern.Length - 1)
            {
                // then the next char must be a dot .'.
                if (pattern[index + 1] != '.')
                {
                    return false;
                }
            }

            // only one (A) wildcard is supported
            int i2 = pattern.IndexOf('*', index + 1);
            if (i2 != -1) return false;

            // match the end of the pattern
            string end = pattern.Substring(index + 1);
            int length = hostname.Length - end.Length;
            // no point to check a pattern that is longer than the hostname
            if (length