lokinet/llarp/dns/srv_data.cpp
Thomas Winget b1c14af938
SRV Record handling for introsets (#1331)
* update loki-mq submodule for tuple support

* srv record reply implementation

still need to encode srv records into intro sets / router contacts
as well as decode from them and match against queried service.proto

* inverted condition fix in config code

* SRV record struct (de-)serialization for intro sets

* parsing and using srv records from config (for/in introsets)

* adopt str utils from core and use for srv parsing

* changes to repeat requests

no longer drop repeat requests on the floor, but do not make
an *actual* request for them if one is in progress.

do not call reply hook for each reply for a request, as
each userland request is actually made into several lokinet
requests and this would result in duplicate replies.

* fetch SRVs from introsets for .loki

* make format

* dns and srv fixes, srv appears to be working
2020-08-31 16:07:17 -04:00

103 lines
2.2 KiB
C++

#include <dns/srv_data.hpp>
#include <util/str.hpp>
#include <util/logging/logger.hpp>
#include <limits>
namespace llarp::dns
{
bool
SRVData::IsValid() const
{
// if target is of first two forms outlined above
if (target == "." or target.size() == 0)
{
return true;
}
// check target size is not absurd
if (target.size() > TARGET_MAX_SIZE)
{
LogWarn("SRVData target larger than max size (", TARGET_MAX_SIZE, ")");
return false;
}
// does target end in .loki?
size_t pos = target.find(".loki");
if (pos != std::string::npos && pos == (target.size() - 5))
{
return true;
}
// does target end in .snode?
pos = target.find(".snode");
if (pos != std::string::npos && pos == (target.size() - 6))
{
return true;
}
// if we're here, target is invalid
LogWarn("SRVData invalid");
return false;
}
SRVTuple
SRVData::toTuple() const
{
return std::make_tuple(service_proto, priority, weight, port, target);
}
SRVData
SRVData::fromTuple(SRVTuple tuple)
{
SRVData s;
std::tie(s.service_proto, s.priority, s.weight, s.port, s.target) = std::move(tuple);
return s;
}
bool
SRVData::fromString(std::string_view srvString)
{
LogDebug("SRVData::fromString(\"", srvString, "\")");
// split on spaces, discard trailing empty strings
auto splits = split(srvString, " ", false);
if (splits.size() != 5 && splits.size() != 4)
{
LogWarn("SRV record should have either 4 or 5 space-separated parts");
return false;
}
service_proto = splits[0];
if (not parse_int(splits[1], priority))
{
LogWarn("SRV record failed to parse \"", splits[1], "\" as uint16_t (priority)");
return false;
}
if (not parse_int(splits[2], weight))
{
LogWarn("SRV record failed to parse \"", splits[2], "\" as uint16_t (weight)");
return false;
}
if (not parse_int(splits[3], port))
{
LogWarn("SRV record failed to parse \"", splits[3], "\" as uint16_t (port)");
return false;
}
if (splits.size() == 5)
target = splits[4];
else
target = "";
return IsValid();
}
} // namespace llarp::dns