Opened 8 years ago

Last modified 3 years ago

#4734 new enhancement

Tor DNS resolver only supports UDP sockets so can't resolve large RRs

Reported by: murble Owned by:
Priority: Low Milestone: Tor: unspecified
Component: Core Tor/Tor Version:
Severity: Normal Keywords: dns needs-design tor-relay prop219
Cc: intrigeri@…, tobias@… Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description

When Tor attempts to resolve a RR and receives truncated
required, it gives up and fails rather than trying again over
a TCP socket, as an example:

tor-resolve test2.pho.be # works,
whilst
tor-resolve test1.pho.be # always fails.

The problem seems to be in evdns.c / libevent

Child Tickets

Change History (7)

comment:1 Changed 8 years ago by nickm

Keywords: needs-proposal added
Milestone: Tor: unspecified
Type: defectenhancement
Version: Tor: unspecified

This probably make the most sense to tackle as part of a larger effort to support real DNS requests over Tor. Right now, even if Tor servers could receive a record larger than a UDP packet will support, it wouldn't be enough, since there would be no specified way in the Tor lookup protocol to send it back to a client.

So for starters, we're going to need a "get dns right in tor" proposal. That'll probably want a ticket of its own, unless we already have one

comment:2 Changed 7 years ago by nickm

Keywords: tor-relay added

comment:3 Changed 7 years ago by nickm

Component: Tor RelayTor

comment:4 Changed 6 years ago by intrigeri

Cc: intrigeri@… added

comment:5 Changed 6 years ago by cypherpunks

See #11741 too. It happens for real.

comment:6 Changed 6 years ago by ToBeFree

Cc: tobias@… added

comment:7 Changed 3 years ago by nickm

Keywords: needs-design prop219 added; needs-proposal removed
Severity: Normal
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