lokinet/llarp/net/net_bits.hpp
Thomas Winget 7caa87862e standardize include format and pragma once
All #ifndef guards on headers have been removed, I think,
in favor of #pragma once

Headers are now included as `#include "filename"` if the included file
resides in the same directory as the file including it, or any
subdirectory therein.  Otherwise they are included as
`#include <project/top/dir/relative/path/filename>`

The above does not include system/os headers.
2021-03-09 19:01:41 -05:00

52 lines
1.3 KiB
C++

#pragma once
#include "net_int.hpp"
namespace llarp
{
/// get a netmask with the higest numset bits set
constexpr huint128_t
_netmask_ipv6_bits(uint32_t numset)
{
return (128 - numset) ? (huint128_t{1} << numset) | _netmask_ipv6_bits(numset + 1)
: huint128_t{0};
}
constexpr huint128_t
netmask_ipv6_bits(uint32_t numset)
{
return _netmask_ipv6_bits(128 - numset);
}
/// get a netmask with the higest numset bits set
constexpr uint32_t
_netmask_ipv4_bits(uint32_t numset)
{
return (32 - numset) ? (1 << numset) | _netmask_ipv4_bits(numset + 1) : 0;
}
/// get a netmask given some /N range
constexpr huint32_t
netmask_ipv4_bits(uint32_t num)
{
return huint32_t{_netmask_ipv4_bits(32 - num)};
}
constexpr huint32_t
ipaddr_ipv4_bits(uint32_t a, uint32_t b, uint32_t c, uint32_t d)
{
return huint32_t{(d) | (c << 8) | (b << 16) | (a << 24)};
}
// IPv4 mapped address live at ::ffff:0:0/96
constexpr std::array<uint8_t, 12> ipv4_map_prefix{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff};
constexpr bool
ipv6_is_mapped_ipv4(const in6_addr& addr)
{
for (size_t i = 0; i < ipv4_map_prefix.size(); i++)
if (addr.s6_addr[i] != ipv4_map_prefix[i])
return false;
return true;
}
} // namespace llarp