mirror of
https://github.com/OpenVPN/openvpn3.git
synced 2024-09-19 19:52:15 +02:00
dde1574596
This is the result after running 'clang-format -i' on all C++ files and headers, with the defined formatting rules in .clang-format. Only the openvpn/common/unicode-impl.hpp has been excluded, as that is mostly a copy of an external project. Signed-off-by: David Sommerseth <davids@openvpn.net>
210 lines
5.0 KiB
C++
210 lines
5.0 KiB
C++
// 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) 2012-2022 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_SSL_DATALIMIT_H
|
|
#define OPENVPN_SSL_DATALIMIT_H
|
|
|
|
#include <openvpn/common/exception.hpp>
|
|
|
|
namespace openvpn {
|
|
// Helper for handling keys which can have an upper limit
|
|
// on maximum amount of data encrypted/decrypted, such
|
|
// as Blowfish.
|
|
class DataLimit
|
|
{
|
|
public:
|
|
typedef unsigned int size_type;
|
|
|
|
enum Mode
|
|
{
|
|
Encrypt = 0,
|
|
Decrypt = 1,
|
|
};
|
|
|
|
enum State
|
|
{
|
|
None = 0,
|
|
Green = 1,
|
|
Red = 2,
|
|
};
|
|
|
|
struct Parameters
|
|
{
|
|
size_type encrypt_red_limit = 0;
|
|
size_type decrypt_red_limit = 0;
|
|
};
|
|
|
|
DataLimit(const Parameters &p)
|
|
: encrypt(p.encrypt_red_limit),
|
|
decrypt(p.decrypt_red_limit)
|
|
{
|
|
}
|
|
|
|
State update_state(const Mode mode, const State newstate)
|
|
{
|
|
return elgible(mode, component(mode).update_state(newstate));
|
|
}
|
|
|
|
State add(const Mode mode, const size_type n)
|
|
{
|
|
return elgible(mode, component(mode).add(n));
|
|
}
|
|
|
|
bool is_decrypt_green()
|
|
{
|
|
return decrypt.get_state() >= Green;
|
|
}
|
|
|
|
static const char *mode_str(const Mode m)
|
|
{
|
|
switch (m)
|
|
{
|
|
case Encrypt:
|
|
return "Encrypt";
|
|
case Decrypt:
|
|
return "Decrypt";
|
|
default:
|
|
return "Mode_???";
|
|
}
|
|
}
|
|
|
|
static const char *state_str(const State s)
|
|
{
|
|
switch (s)
|
|
{
|
|
case None:
|
|
return "None";
|
|
case Green:
|
|
return "Green";
|
|
case Red:
|
|
return "Red";
|
|
default:
|
|
return "State_???";
|
|
}
|
|
}
|
|
|
|
private:
|
|
// Don't return Encrypt-Red until Decrypt-Green
|
|
// has been received. This confirms that the peer
|
|
// is now transmitting on the key ID, making it
|
|
// eligible for renegotiation.
|
|
State elgible(const Mode mode, const State state)
|
|
{
|
|
// Bit positions for Encrypt/Decrypt and Green/Red
|
|
enum
|
|
{
|
|
EG = 1 << 0,
|
|
ER = 1 << 1,
|
|
DG = 1 << 2,
|
|
DR = 1 << 3,
|
|
};
|
|
if (state > None)
|
|
{
|
|
const unsigned int mask = 1 << ((int(state) - 1) + (int(mode) << 1));
|
|
if (!(flags & mask))
|
|
{
|
|
flags |= mask;
|
|
if ((mask & (ER | DG)) && ((flags & (ER | DG)) == (ER | DG)))
|
|
return Red;
|
|
else if (mask & ER)
|
|
return None;
|
|
else
|
|
return state;
|
|
}
|
|
}
|
|
return None;
|
|
}
|
|
|
|
class Component
|
|
{
|
|
public:
|
|
Component(const size_type red_limit_arg)
|
|
: red_limit(red_limit_arg)
|
|
{
|
|
}
|
|
|
|
State add(const size_type n)
|
|
{
|
|
bytes += n;
|
|
return update_state(transition(state));
|
|
}
|
|
|
|
State update_state(const State newstate)
|
|
{
|
|
State ret = None;
|
|
if (newstate > state)
|
|
state = ret = newstate;
|
|
return ret;
|
|
}
|
|
|
|
State get_state() const
|
|
{
|
|
return state;
|
|
}
|
|
|
|
private:
|
|
State transition(State s) const
|
|
{
|
|
switch (s)
|
|
{
|
|
case None:
|
|
if (bytes)
|
|
return Green;
|
|
else
|
|
return None;
|
|
case Green:
|
|
if (red_limit && bytes >= red_limit)
|
|
return Red;
|
|
else
|
|
return None;
|
|
case Red:
|
|
default:
|
|
return None;
|
|
}
|
|
}
|
|
|
|
const size_type red_limit;
|
|
size_type bytes = 0;
|
|
State state = None;
|
|
};
|
|
|
|
Component &component(const Mode m)
|
|
{
|
|
switch (m)
|
|
{
|
|
case Encrypt:
|
|
return encrypt;
|
|
case Decrypt:
|
|
return decrypt;
|
|
default:
|
|
throw Exception("DataLimit::Component: unknown mode");
|
|
}
|
|
}
|
|
|
|
Component encrypt;
|
|
Component decrypt;
|
|
unsigned int flags = 0;
|
|
};
|
|
} // namespace openvpn
|
|
|
|
#endif
|