lokinet/llarp/net/address_info.cpp
Jason Rhinelander 36792d4337
Fix multi-field < ordering
Lots and lots of places in the code had broken < operators because they
are returning something like:

    foo < other.foo or bar < other.bar;

but this breaks both the strict weak ordering requirements that are
required for the "Compare" requirement for things like
std::map/set/priority_queue.

For example:

    a = {.foo=1, .bar=3}
    b = {.foo=3, .bar=1}

does not have an ordering over a and b (both `a < b` and `b < a` are
satisfied at the same time).

This needs to be instead something like:

    foo < other.foo or (foo == other.foo and bar < other.bar)

but that's a bit clunkier, and it is easier to use std::tie for tuple's
built-in < comparison which does the right thing:

    std::tie(foo, bar) < std::tie(other.foo, other.bar)

(Initially I noticed this in SockAddr/sockaddr_in6, but upon further
investigation this extends to the major of multi-field `operator<`'s.)

This fixes it by using std::tie (or something similar) everywhere we are
doing multi-field inequalities.
2022-10-13 16:29:13 -03:00

195 lines
4.3 KiB
C++

#include "address_info.hpp"
#include <stdexcept>
#ifndef _WIN32
#include <arpa/inet.h>
#endif
#include "net.hpp"
#include <llarp/util/bencode.h>
#include <llarp/util/mem.h>
#include <cstring>
namespace llarp
{
bool
operator==(const AddressInfo& lhs, const AddressInfo& rhs)
{
// we don't care about rank
return lhs.pubkey == rhs.pubkey && lhs.port == rhs.port && lhs.dialect == rhs.dialect
&& lhs.ip == rhs.ip;
}
bool
operator<(const AddressInfo& lhs, const AddressInfo& rhs)
{
return std::tie(lhs.rank, lhs.ip, lhs.port) < std::tie(rhs.rank, rhs.ip, rhs.port);
}
std::variant<nuint32_t, nuint128_t>
AddressInfo::IP() const
{
return SockAddr{ip}.getIP();
}
bool
AddressInfo::DecodeKey(const llarp_buffer_t& key, llarp_buffer_t* buf)
{
uint64_t i;
char tmp[128] = {0};
llarp_buffer_t strbuf;
// rank
if (key.startswith("c"))
{
if (!bencode_read_integer(buf, &i))
return false;
if (i > 65536 || i <= 0)
return false;
rank = i;
return true;
}
// dialect
if (key.startswith("d"))
{
if (!bencode_read_string(buf, &strbuf))
return false;
if (strbuf.sz > sizeof(tmp))
return false;
memcpy(tmp, strbuf.base, strbuf.sz);
tmp[strbuf.sz] = 0;
dialect = std::string(tmp);
return true;
}
// encryption public key
if (key.startswith("e"))
{
return pubkey.BDecode(buf);
}
// ip address
if (key.startswith("i"))
{
if (!bencode_read_string(buf, &strbuf))
return false;
if (strbuf.sz >= sizeof(tmp))
return false;
memcpy(tmp, strbuf.base, strbuf.sz);
tmp[strbuf.sz] = 0;
return inet_pton(AF_INET6, tmp, &ip.s6_addr[0]) == 1;
}
// port
if (key.startswith("p"))
{
if (!bencode_read_integer(buf, &i))
return false;
if (i > 65536 || i <= 0)
return false;
port = i;
return true;
}
// version
if (key.startswith("v"))
{
if (!bencode_read_integer(buf, &i))
return false;
return i == llarp::constants::proto_version;
}
// bad key
return false;
}
bool
AddressInfo::BEncode(llarp_buffer_t* buff) const
{
char ipbuff[128] = {0};
const char* ipstr;
if (!bencode_start_dict(buff))
return false;
/* rank */
if (!bencode_write_bytestring(buff, "c", 1))
return false;
if (!bencode_write_uint64(buff, rank))
return false;
/* dialect */
if (!bencode_write_bytestring(buff, "d", 1))
return false;
if (!bencode_write_bytestring(buff, dialect.c_str(), dialect.size()))
return false;
/* encryption key */
if (!bencode_write_bytestring(buff, "e", 1))
return false;
if (!bencode_write_bytestring(buff, pubkey.data(), PUBKEYSIZE))
return false;
/** ip */
ipstr = inet_ntop(AF_INET6, (void*)&ip, ipbuff, sizeof(ipbuff));
if (!ipstr)
return false;
if (!bencode_write_bytestring(buff, "i", 1))
return false;
if (!bencode_write_bytestring(buff, ipstr, strnlen(ipstr, sizeof(ipbuff))))
return false;
/** port */
if (!bencode_write_bytestring(buff, "p", 1))
return false;
if (!bencode_write_uint64(buff, port))
return false;
/** version */
if (!bencode_write_uint64_entry(buff, "v", 1, llarp::constants::proto_version))
return false;
/** end */
return bencode_end(buff);
}
IpAddress
AddressInfo::toIpAddress() const
{
SockAddr addr(ip);
addr.setPort(port);
return IpAddress(addr);
}
void
AddressInfo::fromSockAddr(const SockAddr& addr)
{
const auto* addr6 = static_cast<const sockaddr_in6*>(addr);
memcpy(ip.s6_addr, addr6->sin6_addr.s6_addr, sizeof(ip.s6_addr));
port = addr.getPort();
}
std::string
AddressInfo::ToString() const
{
char tmp[INET6_ADDRSTRLEN] = {0};
inet_ntop(AF_INET6, (void*)&ip, tmp, sizeof(tmp));
return fmt::format("[{}]:{}", tmp, port);
}
void
to_json(nlohmann::json& j, const AddressInfo& a)
{
char tmp[128] = {0};
inet_ntop(AF_INET6, (void*)&a.ip, tmp, sizeof(tmp));
j = nlohmann::json{
{"rank", a.rank},
{"dialect", a.dialect},
{"pubkey", a.pubkey.ToString()},
{"in6_addr", tmp},
{"port", a.port}};
}
} // namespace llarp