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// 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_IPV4_H
#define OPENVPN_ADDR_IPV4_H
#include <cstring> // for std::memcpy, std::memset
#include <sstream>
#include <cstdint> // for std::uint32_t
#include <openvpn/io/io.hpp>
#include <openvpn/common/size.hpp>
#include <openvpn/common/exception.hpp>
#include <openvpn/common/endian.hpp>
#include <openvpn/common/ostream.hpp>
#include <openvpn/common/socktypes.hpp>
#include <openvpn/common/ffs.hpp>
#include <openvpn/common/hexstr.hpp>
#include <openvpn/common/hash.hpp>
#include <openvpn/addr/iperr.hpp>
namespace openvpn {
namespace IP {
class Addr;
}
// Fundamental classes for representing an IPv4 IP address.
namespace IPv4 {
OPENVPN_EXCEPTION(ipv4_exception);
class Addr // NOTE: must be union-legal, so default constructor does not initialize
{
friend class IP::Addr;
public:
enum { SIZE=32 };
typedef std::uint32_t base_type;
typedef std::int32_t signed_base_type;
bool defined() const
{
return true;
}
static Addr from_addr(const Addr& addr)
{
return addr;
}
static Addr from_in_addr(const struct in_addr *in4)
{
Addr ret;
ret.u.addr = ntohl(in4->s_addr);
return ret;
}
struct in_addr to_in_addr() const
{
struct in_addr ret;
ret.s_addr = htonl(u.addr);
return ret;
}
static Addr from_sockaddr(const struct sockaddr_in *sa)
{
Addr ret;
ret.u.addr = ntohl(sa->sin_addr.s_addr);
return ret;
}
struct sockaddr_in to_sockaddr(const unsigned short port=0) const
{
struct sockaddr_in ret;
std::memset(&ret, 0, sizeof(ret));
ret.sin_family = AF_INET;
ret.sin_port = htons(port);
ret.sin_addr.s_addr = htonl(u.addr);
return ret;
}
static Addr from_uint32(const base_type addr) // host byte order
{
Addr ret;
ret.u.addr = addr;
return ret;
}
std::uint32_t to_uint32() const // host byte order
{
return u.addr;
}
static Addr from_uint32_net(const base_type addr) // addr in net byte order
{
Addr ret;
ret.u.addr = ntohl(addr);
return ret;
}
void to_byte_string(unsigned char *bytestr) const
{
*(base_type*)bytestr = ntohl(u.addr);
}
std::uint32_t to_uint32_net() const // return value in net byte order
{
return htonl(u.addr);
}
static Addr from_ulong(unsigned long ul)
{
Addr ret;
ret.u.addr = (base_type)ul;
return ret;
}
// return *this as a unsigned long
unsigned long to_ulong() const
{
return (unsigned long)u.addr;
}
static Addr from_long(long ul)
{
Addr ret;
ret.u.addr = (base_type)(signed_base_type)ul;
return ret;
}
// return *this as a long
long to_long() const
{
return (long)(signed_base_type)u.addr;
}
static Addr from_bytes(const unsigned char *bytes) // host byte order
{
Addr ret;
std::memcpy(ret.u.bytes, bytes, 4);
return ret;
}
static Addr from_bytes_net(const unsigned char *bytes) // network byte order
{
Addr ret;
std::memcpy(ret.u.bytes, bytes, 4);
ret.u.addr = ntohl(ret.u.addr);
return ret;
}
static Addr from_zero()
{
Addr ret;
ret.zero();
return ret;
}
static Addr from_one()
{
Addr ret;
ret.one();
return ret;
}
static Addr from_zero_complement()
{
Addr ret;
ret.zero_complement();
return ret;
}
// build a netmask using given prefix_len
static Addr netmask_from_prefix_len(const unsigned int prefix_len)
{
Addr ret;
ret.u.addr = prefix_len_to_netmask(prefix_len);
return ret;
}
// build a netmask using given extent
Addr netmask_from_extent() const
{
const int lb = find_last_set(u.addr - 1);
return netmask_from_prefix_len(SIZE - lb);
}
static Addr from_string(const std::string& ipstr, const char *title = nullptr)
{
openvpn_io::error_code ec;
openvpn_io::ip::address_v4 a = openvpn_io::ip::make_address_v4(ipstr, ec);
if (ec)
throw ipv4_exception(IP::internal::format_error(ipstr, title, "v4", ec));
return from_asio(a);
}
std::string to_string() const
{
const openvpn_io::ip::address_v4 a = to_asio();
std::string ret = a.to_string();
return ret;
}
static Addr from_hex(const std::string& s)
{
Addr ret;
ret.u.addr = 0;
size_t len = s.length();
size_t base = 0;
if (len > 0 && s[len-1] == 'L')
len -= 1;
if (len >= 2 && s[0] == '0' && s[1] == 'x')
{
base = 2;
len -= 2;
}
if (len < 1 || len > 8)
throw ipv4_exception("parse hex error");
size_t di = (len-1)>>1;
for (int i = (len & 1) ? -1 : 0; i < int(len); i += 2)
{
const size_t idx = base + i;
const int bh = (i >= 0) ? parse_hex_char(s[idx]) : 0;
const int bl = parse_hex_char(s[idx+1]);
if (bh == -1 || bl == -1)
throw ipv4_exception("parse hex error");
ret.u.bytes[Endian::e4(di--)] = (bh<<4) + bl;
}
return ret;
}
std::string to_hex() const
{
std::string ret;
ret.reserve(8);
bool firstnonzero = false;
for (size_t i = 0; i < 4; ++i)
{
const unsigned char b = u.bytes[Endian::e4rev(i)];
if (b || firstnonzero || i == 3)
{
const char bh = b >> 4;
if (bh || firstnonzero)
ret += render_hex_char(bh);
ret += render_hex_char(b & 0x0F);
firstnonzero = true;
}
}
return ret;
}
std::string arpa() const
{
std::ostringstream os;
os << int(u.bytes[Endian::e4(0)]) << '.'
<< int(u.bytes[Endian::e4(1)]) << '.'
<< int(u.bytes[Endian::e4(2)]) << '.'
<< int(u.bytes[Endian::e4(3)]) << ".in-addr.arpa";
return os.str();
}
static Addr from_asio(const openvpn_io::ip::address_v4& asio_addr)
{
Addr ret;
ret.u.addr = (std::uint32_t)asio_addr.to_uint();
return ret;
}
openvpn_io::ip::address_v4 to_asio() const
{
return openvpn_io::ip::address_v4(u.addr);
}
Addr operator&(const Addr& other) const {
Addr ret;
ret.u.addr = u.addr & other.u.addr;
return ret;
}
Addr operator|(const Addr& other) const {
Addr ret;
ret.u.addr = u.addr | other.u.addr;
return ret;
}
Addr operator+(const long delta) const {
Addr ret;
ret.u.addr = u.addr + (std::uint32_t)delta;
return ret;
}
Addr operator+(const Addr& other) const {
Addr ret;
ret.u.addr = u.addr + other.u.addr;
return ret;
}
Addr operator-(const long delta) const {
return operator+(-delta);
}
Addr operator-(const Addr& other) const {
Addr ret;
ret.u.addr = u.addr - other.u.addr;
return ret;
}
Addr operator*(const Addr& other) const {
Addr ret;
ret.u.addr = u.addr * other.u.addr;
return ret;
}
Addr operator/(const Addr& other) const {
Addr ret;
ret.u.addr = u.addr / other.u.addr;
return ret;
}
Addr operator%(const Addr& other) const {
Addr ret;
ret.u.addr = u.addr % other.u.addr;
return ret;
}
Addr operator<<(const unsigned int shift) const {
Addr ret;
ret.u.addr = u.addr << shift;
return ret;
}
Addr operator>>(const unsigned int shift) const {
Addr ret;
ret.u.addr = u.addr >> shift;
return ret;
}
Addr operator~() const {
Addr ret;
ret.u.addr = ~u.addr;
return ret;
}
// return the network that contains the current address
Addr network_addr(const unsigned int prefix_len) const
{
Addr ret;
ret.u.addr = u.addr & prefix_len_to_netmask(prefix_len);
return ret;
}
bool operator==(const Addr& other) const
{
return u.addr == other.u.addr;
}
bool operator!=(const Addr& other) const
{
return u.addr != other.u.addr;
}
bool operator<(const Addr& other) const
{
return u.addr < other.u.addr;
}
bool operator>(const Addr& other) const
{
return u.addr > other.u.addr;
}
bool operator<=(const Addr& other) const
{
return u.addr <= other.u.addr;
}
bool operator>=(const Addr& other) const
{
return u.addr >= other.u.addr;
}
bool unspecified() const
{
return all_zeros();
}
bool specified() const
{
return !unspecified();
}
bool all_zeros() const
{
return u.addr == 0;
}
bool all_ones() const
{
return ~u.addr == 0;
}
bool is_loopback() const
{
return (u.addr & 0x7F000000) == 0x7F000000;
}
// number of network bits in netmask,
// throws exception if addr is not a netmask
unsigned int prefix_len() const
{
const int ret = prefix_len_32(u.addr);
if (ret >= 0)
return ret;
else
throw ipv4_exception("malformed netmask");
}
int prefix_len_nothrow() const
{
return prefix_len_32(u.addr);
}
// number of host bits in netmask
unsigned int host_len() const
{
return SIZE - prefix_len();
}
// return the number of host addresses contained within netmask
Addr extent_from_netmask() const
{
Addr ret;
ret.u.addr = extent_from_netmask_uint32();
return ret;
}
std::uint32_t extent_from_netmask_uint32() const
{
const unsigned int hl = host_len();
if (hl < SIZE)
return 1 << hl;
else if (hl == SIZE)
return 0;
else
throw ipv4_exception("extent overflow");
}
// convert netmask in addr to prefix_len, will return -1 on error
static int prefix_len_32(const std::uint32_t addr)
{
if (addr == ~std::uint32_t(0))
return 32;
else if (addr == 0)
return 0;
else
{
unsigned int high = 32;
unsigned int low = 1;
for (unsigned int i = 0; i < 5; ++i)
{
const unsigned int mid = (high + low) / 2;
const IPv4::Addr::base_type test = prefix_len_to_netmask_unchecked(mid);
if (addr == test)
return mid;
else if (addr > test)
low = mid;
else
high = mid;
}
return -1;
}
}
// address size in bits
static unsigned int size()
{
return SIZE;
}
template <typename HASH>
void hash(HASH& h) const
{
h(u.addr);
}
#ifdef HAVE_CITYHASH
std::size_t hashval() const
{
HashSizeT h;
hash(h);
return h.value();
}
#endif
#ifdef OPENVPN_IP_IMMUTABLE
private:
#endif
void negate()
{
u.addr = ~u.addr;
}
void zero()
{
u.addr = 0;
}
void zero_complement()
{
u.addr = ~0;
}
void one()
{
u.addr = 1;
}
Addr& operator++()
{
++u.addr;
return *this;
}
Addr& operator+=(const long delta)
{
u.addr += (std::uint32_t)delta;
return *this;
}
Addr& operator-=(const long delta)
{
return operator+=(-delta);
}
private:
static base_type prefix_len_to_netmask_unchecked(const unsigned int prefix_len)
{
if (prefix_len)
return ~((1 << (SIZE - prefix_len)) - 1);
else
return 0;
}
static base_type prefix_len_to_netmask(const unsigned int prefix_len)
{
if (prefix_len <= SIZE)
return prefix_len_to_netmask_unchecked(prefix_len);
else
throw ipv4_exception("bad prefix len");
}
union {
base_type addr; // host byte order
unsigned char bytes[4];
} u;
};
OPENVPN_OSTREAM(Addr, to_string)
}
}
#ifdef HAVE_CITYHASH
OPENVPN_HASH_METHOD(openvpn::IPv4::Addr, hashval);
#endif
#endif // OPENVPN_ADDR_IPV4_H