Merge commit '86cc97e55fe346502462284d2e636a2b3708163e' as 'Sources/OpenVPN3'

2026-04-24 00:00:05 +08:00 · 2020-02-24 14:43:11 +03:00
parent 133b3756e6 86cc97e55f
commit 32f1555929
655 changed files with 146468 additions and 0 deletions
@@ -0,0 +1,145 @@
+//    OpenVPN -- An application to securely tunnel IP networks
+//               over a single port, with support for SSL/TLS-based
+//               session authentication and key exchange,
+//               packet encryption, packet authentication, and
+//               packet compression.
+//
+//    Copyright (C) 2012-2017 OpenVPN Inc.
+//
+//    This program is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU Affero General Public License Version 3
+//    as published by the Free Software Foundation.
+//
+//    This program is distributed in the hope that it will be useful,
+//    but WITHOUT ANY WARRANTY; without even the implied warranty of
+//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//    GNU Affero General Public License for more details.
+//
+//    You should have received a copy of the GNU Affero General Public License
+//    along with this program in the COPYING file.
+//    If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef OPENVPN_BUFFER_ZLIB_H
+#define OPENVPN_BUFFER_ZLIB_H
+
+#ifdef HAVE_ZLIB
+
+#include <cstring> // for std::memset
+
+#include <zlib.h>
+
+#include <openvpn/common/exception.hpp>
+#include <openvpn/buffer/buffer.hpp>
+#include <openvpn/buffer/buflist.hpp>
+
+namespace openvpn {
+  namespace ZLib {
+    OPENVPN_EXCEPTION(zlib_error);
+
+    class ZStreamBase // used internally by compress_gzip/decompress_gzip
+    {
+    public:
+      z_stream s;
+    protected:
+      ZStreamBase()  { std::memset(&s, 0, sizeof(s)); }
+    private:
+      ZStreamBase(const ZStreamBase&) = delete;
+      ZStreamBase& operator=(const ZStreamBase&) = delete;
+    };
+
+    inline BufferPtr compress_gzip(BufferPtr src,
+				   const size_t headroom,
+				   const size_t tailroom,
+				   const int level,
+				   const int window_bits=15,
+				   const int mem_level=8)
+    {
+      constexpr int GZIP_ENCODING = 16;
+
+      struct ZStream : public ZStreamBase {
+	~ZStream() { ::deflateEnd(&s); }
+      };
+
+      if (src)
+	{
+	  int status;
+	  ZStream zs;
+	  zs.s.next_in = src->data();
+	  zs.s.avail_in = src->size();
+	  status = ::deflateInit2(&zs.s,
+				  level,
+				  Z_DEFLATED,
+				  GZIP_ENCODING + window_bits,
+				  mem_level,
+				  Z_DEFAULT_STRATEGY);
+	  if (status != Z_OK)
+	    OPENVPN_THROW(zlib_error, "zlib deflateinit2 failed, error=" << status);
+	  const uLong outcap = ::deflateBound(&zs.s, src->size());
+	  BufferPtr b = new BufferAllocated(outcap + headroom + tailroom, 0);
+	  b->init_headroom(headroom);
+	  zs.s.next_out = b->data();
+	  zs.s.avail_out = outcap;
+	  status = ::deflate(&zs.s, Z_FINISH);
+	  if (status != Z_STREAM_END)
+	    OPENVPN_THROW(zlib_error, "zlib deflate failed, error=" << status);
+	  b->set_size(zs.s.total_out);
+	  return b;
+	}
+      else
+	return BufferPtr();
+    }
+
+    inline BufferPtr decompress_gzip(BufferPtr src,
+				     const size_t headroom,
+				     const size_t tailroom,
+				     const size_t max_size,
+				     const size_t block_size=4096,
+				     const int window_bits=15)
+    {
+      constexpr int GZIP_ENCODING = 16;
+
+      struct ZStream : public ZStreamBase {
+	~ZStream() { ::inflateEnd(&s); }
+      };
+
+      if (src)
+	{
+	  int status;
+	  ZStream zs;
+	  zs.s.next_in = src->data();
+	  zs.s.avail_in = src->size();
+	  status = ::inflateInit2(&zs.s, GZIP_ENCODING + window_bits);
+	  if (status != Z_OK)
+	    OPENVPN_THROW(zlib_error, "zlib inflateinit2 failed, error=" << status);
+
+	  BufferList blist;
+	  size_t hr = headroom;
+	  size_t tr = tailroom;
+	  do {
+	    // use headroom/tailroom on first block to take advantage
+	    // of BufferList::join() optimization for one-block lists
+	    BufferPtr b = new BufferAllocated(block_size + hr + tr, 0);
+	    b->init_headroom(hr);
+	    const size_t avail = b->remaining(tr);
+	    zs.s.next_out = b->data();
+	    zs.s.avail_out = avail;
+	    status = ::inflate(&zs.s, Z_SYNC_FLUSH);
+	    if (status != Z_OK && status != Z_STREAM_END)
+	      OPENVPN_THROW(zlib_error, "zlib inflate failed, error=" << status);
+	    b->set_size(avail - zs.s.avail_out);
+	    blist.push_back(std::move(b));
+	    if (max_size && zs.s.total_out > max_size)
+	      OPENVPN_THROW(zlib_error, "zlib inflate max_size " << max_size << " exceeded");
+	    hr = tr = 0;
+	  } while (status == Z_OK);
+	  return blist.join(headroom, tailroom, true);
+	}
+      else
+	return BufferPtr();
+    }
+
+  }
+}
+
+#endif
+#endif