2022-03-15 18:00:53 +00:00
|
|
|
// (c) Copyright Ascensio System SIA 2010-2022
|
|
|
|
//
|
|
|
|
// This program is a free software product.
|
|
|
|
// You can redistribute it and/or modify it under the terms
|
|
|
|
// of the GNU Affero General Public License (AGPL) version 3 as published by the Free Software
|
|
|
|
// Foundation. In accordance with Section 7(a) of the GNU AGPL its Section 15 shall be amended
|
|
|
|
// to the effect that Ascensio System SIA expressly excludes the warranty of non-infringement of
|
|
|
|
// any third-party rights.
|
|
|
|
//
|
|
|
|
// This program is distributed WITHOUT ANY WARRANTY, without even the implied warranty
|
|
|
|
// of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. For details, see
|
|
|
|
// the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
|
|
|
|
//
|
|
|
|
// You can contact Ascensio System SIA at Lubanas st. 125a-25, Riga, Latvia, EU, LV-1021.
|
|
|
|
//
|
|
|
|
// The interactive user interfaces in modified source and object code versions of the Program must
|
|
|
|
// display Appropriate Legal Notices, as required under Section 5 of the GNU AGPL version 3.
|
|
|
|
//
|
|
|
|
// Pursuant to Section 7(b) of the License you must retain the original Product logo when
|
|
|
|
// distributing the program. Pursuant to Section 7(e) we decline to grant you any rights under
|
|
|
|
// trademark law for use of our trademarks.
|
|
|
|
//
|
|
|
|
// All the Product's GUI elements, including illustrations and icon sets, as well as technical writing
|
|
|
|
// content are licensed under the terms of the Creative Commons Attribution-ShareAlike 4.0
|
|
|
|
// International. See the License terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode
|
|
|
|
|
2022-02-03 15:26:44 +00:00
|
|
|
namespace ASC.Common.Utils;
|
|
|
|
|
|
|
|
public static class MimeHeaderUtils
|
2019-05-15 14:56:09 +00:00
|
|
|
{
|
2022-02-08 11:07:28 +00:00
|
|
|
public static string EncodeMime(string mimeHeaderValue)
|
|
|
|
{
|
|
|
|
return EncodeMime(mimeHeaderValue, Encoding.UTF8, false);
|
|
|
|
}
|
2019-05-15 14:56:09 +00:00
|
|
|
|
2022-02-03 15:26:44 +00:00
|
|
|
public static string EncodeMime(string mimeHeaderValue, Encoding charset, bool split)
|
|
|
|
{
|
|
|
|
if (MustEncode(mimeHeaderValue))
|
2019-05-15 14:56:09 +00:00
|
|
|
{
|
2022-02-03 15:26:44 +00:00
|
|
|
var result = new StringBuilder();
|
|
|
|
var data = charset.GetBytes(mimeHeaderValue);
|
|
|
|
var maxEncodedTextSize = split ? 75 - ("=?" + charset.WebName + "?" + "B"/*Base64 encode*/ + "?" + "?=").Length : int.MaxValue;
|
2019-05-15 14:56:09 +00:00
|
|
|
|
2022-02-03 15:26:44 +00:00
|
|
|
result.Append("=?" + charset.WebName + "?B?");
|
|
|
|
var stored = 0;
|
|
|
|
var base64 = Convert.ToBase64String(data);
|
2022-02-01 14:51:29 +00:00
|
|
|
|
2022-02-03 15:26:44 +00:00
|
|
|
for (var i = 0; i < base64.Length; i += 4)
|
|
|
|
{
|
|
|
|
// Encoding buffer full, create new encoded-word.
|
|
|
|
if (stored + 4 > maxEncodedTextSize)
|
2019-05-15 14:56:09 +00:00
|
|
|
{
|
2022-02-03 15:26:44 +00:00
|
|
|
result.Append("?=\r\n =?" + charset.WebName + "?B?");
|
|
|
|
stored = 0;
|
2019-05-15 14:56:09 +00:00
|
|
|
}
|
2022-02-01 14:51:29 +00:00
|
|
|
|
2022-02-03 15:26:44 +00:00
|
|
|
result.Append(base64, i, 4);
|
|
|
|
stored += 4;
|
2019-05-15 14:56:09 +00:00
|
|
|
}
|
|
|
|
|
2022-02-03 15:26:44 +00:00
|
|
|
result.Append("?=");
|
|
|
|
|
|
|
|
return result.ToString();
|
|
|
|
}
|
2022-02-08 11:07:28 +00:00
|
|
|
|
2022-02-03 15:26:44 +00:00
|
|
|
return mimeHeaderValue;
|
2019-05-15 14:56:09 +00:00
|
|
|
}
|
2022-02-03 15:26:44 +00:00
|
|
|
|
2022-02-08 11:07:28 +00:00
|
|
|
public static bool MustEncode(string text)
|
|
|
|
{
|
|
|
|
return !string.IsNullOrEmpty(text) && text.Any(c => c > 127);
|
|
|
|
}
|
|
|
|
}
|