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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) 2012-2017 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_ADDR_ROUTE_H
#define OPENVPN_ADDR_ROUTE_H
#include <string>
#include <sstream>
#include <vector>
#include <cstdint> // for std::uint32_t
#include <tuple>
#include <openvpn/common/size.hpp>
#include <openvpn/common/exception.hpp>
#include <openvpn/common/number.hpp>
#include <openvpn/common/to_string.hpp>
#include <openvpn/common/split.hpp>
#include <openvpn/common/hash.hpp>
#include <openvpn/addr/ip.hpp>
namespace openvpn {
namespace IP {
// Basic route object
template <typename ADDR>
class RouteType
{
public:
typedef ADDR Addr;
ADDR addr;
unsigned int prefix_len;
OPENVPN_EXCEPTION(route_error);
RouteType()
: prefix_len(0)
{
}
RouteType(const std::string& rtstr, const char *title = nullptr)
: RouteType(RouteType::from_string(rtstr, title))
{
}
RouteType(const std::string& rtstr, const std::string& title)
: RouteType(RouteType::from_string(rtstr, title.c_str()))
{
}
RouteType(const ADDR& addr_arg,
const unsigned int prefix_len_arg)
: addr(addr_arg),
prefix_len(prefix_len_arg)
{
}
static RouteType from_string(const std::string& rtstr, const char *title = nullptr)
{
RouteType r;
std::vector<std::string> pair;
pair.reserve(2);
Split::by_char_void<std::vector<std::string>, NullLex, Split::NullLimit>(pair, rtstr, '/', 0, 1);
r.addr = ADDR::from_string(pair[0], title);
if (pair.size() >= 2)
{
r.prefix_len = parse_number_throw<unsigned int>(pair[1], "prefix length");
if (r.prefix_len > r.addr.size())
OPENVPN_THROW(route_error, (title ? title : "route") << " : bad prefix length : " << rtstr);
}
else
r.prefix_len = r.addr.size();
return r;
}
bool defined() const
{
return addr.defined();
}
IP::Addr::Version version() const
{
return addr.version();
}
IP::Addr::VersionMask version_mask() const
{
return addr.version_mask();
}
RouteType<IPv4::Addr> to_ipv4() const
{
return RouteType<IPv4::Addr>(addr.to_ipv4(), prefix_len);
}
RouteType<IPv6::Addr> to_ipv6() const
{
return RouteType<IPv6::Addr>(addr.to_ipv6(), prefix_len);
}
ADDR netmask() const
{
return netmask_(addr, prefix_len);
}
size_t extent() const
{
return netmask().extent_from_netmask().to_ulong();
}
bool is_canonical() const
{
return (addr & netmask()) == addr;
}
void force_canonical()
{
addr = addr & netmask();
}
void verify_canonical() const
{
if (!is_canonical())
throw route_error("route not canonical: " + to_string());
}
bool is_host() const
{
return addr.defined() && prefix_len == addr.size();
}
unsigned int host_bits() const
{
if (prefix_len < addr.size())
return addr.size() - prefix_len;
else
return 0;
}
bool contains(const ADDR& a) const // assumes canonical address/routes
{
if (addr.defined() && version_eq(addr, a))
return (a & netmask()) == addr;
else
return false;
}
bool contains(const RouteType& r) const // assumes canonical routes
{
return contains(r.addr) && r.prefix_len >= prefix_len;
}
bool split(RouteType& r1, RouteType& r2) const // assumes we are canonical
{
if (!is_host())
{
const unsigned int newpl = prefix_len + 1;
r1.addr = addr;
r1.prefix_len = newpl;
r2.addr = addr + netmask_(addr, newpl).extent_from_netmask();
r2.prefix_len = newpl;
return true;
}
return false;
}
std::string to_string() const
{
return addr.to_string() + '/' + openvpn::to_string(prefix_len);
}
std::string to_string_by_netmask() const
{
return addr.to_string() + ' ' + netmask().to_string();
}
bool operator==(const RouteType& other) const
{
return std::tie(prefix_len, addr) == std::tie(other.prefix_len, other.addr);
}
bool operator!=(const RouteType& other) const
{
return std::tie(prefix_len, addr) != std::tie(other.prefix_len, other.addr);
}
bool operator<(const RouteType& other) const
{
return std::tie(prefix_len, addr) < std::tie(other.prefix_len, other.addr);
}
template <typename HASH>
void hash(HASH& h) const
{
addr.hash(h);
h(prefix_len);
}
#ifdef HAVE_CITYHASH
std::size_t hash_value() const
{
HashSizeT h;
hash(h);
return h.value();
}
#endif
private:
static IPv4::Addr netmask_(const IPv4::Addr&, unsigned int prefix_len)
{
return IPv4::Addr::netmask_from_prefix_len(prefix_len);
}
static IPv6::Addr netmask_(const IPv6::Addr&, unsigned int prefix_len)
{
return IPv6::Addr::netmask_from_prefix_len(prefix_len);
}
static IP::Addr netmask_(const IP::Addr& addr, unsigned int prefix_len)
{
return IP::Addr::netmask_from_prefix_len(addr.version(), prefix_len);
}
static bool version_eq(const IPv4::Addr&, const IPv4::Addr&)
{
return true;
}
static bool version_eq(const IPv6::Addr&, const IPv6::Addr&)
{
return true;
}
static bool version_eq(const IP::Addr& a1, const IP::Addr& a2)
{
return a1.version() == a2.version();
}
};
template <typename ADDR>
struct RouteTypeList : public std::vector<RouteType<ADDR>>
{
typedef std::vector< RouteType<ADDR> > Base;
OPENVPN_EXCEPTION(route_list_error);
std::string to_string() const
{
std::ostringstream os;
for (auto &r : *this)
os << r.to_string() << std::endl;
return os.str();
}
IP::Addr::VersionMask version_mask() const
{
IP::Addr::VersionMask mask = 0;
for (auto &r : *this)
mask |= r.version_mask();
return mask;
}
void verify_canonical() const
{
for (auto &r : *this)
r.verify_canonical();
}
template <typename R>
bool contains(const R& c) const
{
for (auto &r : *this)
if (r.contains(c))
return true;
return false;
}
};
typedef RouteType<IP::Addr> Route;
typedef RouteType<IPv4::Addr> Route4;
typedef RouteType<IPv6::Addr> Route6;
typedef RouteTypeList<IP::Addr> RouteList;
typedef RouteTypeList<IPv4::Addr> Route4List;
typedef RouteTypeList<IPv6::Addr> Route6List;
OPENVPN_OSTREAM(Route, to_string);
OPENVPN_OSTREAM(Route4, to_string);
OPENVPN_OSTREAM(Route6, to_string);
OPENVPN_OSTREAM(RouteList, to_string);
OPENVPN_OSTREAM(Route4List, to_string);
OPENVPN_OSTREAM(Route6List, to_string);
inline Route route_from_string_prefix(const std::string& addrstr,
const unsigned int prefix_len,
const std::string& title,
const IP::Addr::Version required_version = IP::Addr::UNSPEC)
{
Route r;
r.addr = IP::Addr(addrstr, title, required_version);
r.prefix_len = prefix_len;
if (r.prefix_len > r.addr.size())
OPENVPN_THROW(Route::route_error, title << " : bad prefix length : " << addrstr);
return r;
}
inline Route route_from_string(const std::string& rtstr,
const std::string& title,
const IP::Addr::Version required_version = IP::Addr::UNSPEC)
{
Route r(rtstr, title);
r.addr.validate_version(title, required_version);
return r;
}
}
}
#ifdef HAVE_CITYHASH
OPENVPN_HASH_METHOD(openvpn::IP::Route, hash_value);
OPENVPN_HASH_METHOD(openvpn::IP::Route4, hash_value);
OPENVPN_HASH_METHOD(openvpn::IP::Route6, hash_value);
#endif
#endif