Thank you for the bug report and your patch.

For the record, we've removed the SRV record for keys.gentoo.org for now, to work around the problem. Without the SRV record, everything works as expected.

Seems it gets a record but is not able to parse it (gnupg/dirmngr/dns-stuff.c:getsrv-standard) in your setup. Not sure why it loops - need to debug it.

Was fixed in 2.3.5

Actually this is pretty obvious; we better ignore such misbehaving servers.

Hi guys, I just tested the git version (426d82fcf1c133bfc1d5c931109d71db3f3815a9) and it works well thank you.

Fixed in 2.2.33.

I don't know if it's same in your case, but to fix my case, I pushed a change rG48359c723206: dns: Make reading resolv.conf more robust.

I managed to create a case. Put a line:

BTW, in your screen shot (log is preferred here), it shows 1c00, that must be actually written as AAAA (0x1c). In the bug T3803, we saw byte sequence like that, additional 00 was added then resulted malformed DNS packet.

dots are not allowed in hostnames.

OK, I'll gdb in there to see what happens. My domain is a classic pgp.domain.com

Ah, other possible case is .. in hostname.

It's hard to investigate your problem, with no information of host for the query.
I mean, there is no case to replicate (for us).

Granted I'm not familiar with the functions and it may not be applicable, but the DNS resolver functions in the GNU C Library have semi-recently gained parameters (RES_USE_DNSSEC) to check for DNSSEC validation IIRC. Recent versions of glibc also don't trust the 'ad' bit unless an indication of its trustworthiness is set in /etc/resolv.conf, say if using a local validating resolver, so one can be sure that it's trustworthy. It also appears musl libc may support this.

Or it might be related issue of name server access like in T3168: dirmngr: gpg: keyserver receive failed: No keyserver available.

This must be an issue of SRV record retrieval.
Merging.

DANE for OpenPGP is an experimental RFC (RFC-7929) and it is likely that we will remove the support because it is too hard for most users to add keys to a zone. Further a validating resolver on the desktop is too hard to maintain and the cause of too many other failures. And no, unbound etc is not an option because it is not usable by the majority of GnuPG users.

The same concern has been reported at https://bugs.debian.org/964033 -- if dirmngr is not going to follow the specification, it should at least document (and maybe warn?) about how it is divergent.

Ping.

Fixed in master.

This part of code is questionable. It always comes fp!=NULL, so the part should be removed.
If fp==NULL, use of tmpfile is quite questionable because a user can't know where the trace output goes.
I'm going to remove that part.

WKD and DANE/OPENPGPKEY offer rather distinct properties. I'd be hard-pressed to say that one is "better" than the other without understanding the threat model and concerns of the evaluator:

DNSSEC is a centralized CA system. Just different than the TLS one. Given that Certificate Transparency exists I'd say DNSSEC is less transparent than TLS. For example if you happen to have a .ly domain then the Libyan can silently control your signed zone. Given that there is no CT for DNSSEC they can do so selectively, for any connection they want. It wouldn't be the first problem with them.

In T4618#128103, @wiktor-k wrote:

I'm left wondering: are there cases where OPENPGPKEY would be preferred over WKD?

Is this really necessary to duplicate functionality that already is provided by Web Key Directory?

I agree, many currently-shipped DNS client library implementations do not provide DNSSEC validity checks.

Sure it is not validated. Standard clients do not provide the system features to do that. That is one of the problems with DNSSEC adoption - it works only for servers in practice.

I asked you to carry this to a mailing list and not re-open this task.

Are you not reading what I am saying to you?? Once again, your explanation is INVALID because that would mean that gnupg would be BROKEN, because it would be a NON-COMPLIANT http client according to the RFC I quoted.

I explained why the keyserver access requires access to the DNS. If that is not possible the keyserver code will not work. If you don't allow DNS to work you either have to use Tor (which we use to also tunnel DNS requests) or get your keys from elsewhere. Also note that the keyserver network is current several broken and under DoS and thus it is unlikely that it can be operated in the future.

HTTP/1.1 spec, RFC 7230, Section 5.4, paragraph 2:
https://tools.ietf.org/html/rfc7230#section-5.4

Please be so kind and point me to the specs stating that you should put the IP address into Host:

It's up to GPG to send the Host header that shows the user's intent.

So in short you want:

1. Allow to specify a keyserver by IP without any DNS lookups.
2. When connecting via IP use the IP address for Host:.

Also might I add, this used to work perfectly fine in gnupg14. It seems that somewhere along the line a regression was introduced that is causing this erroneous non-compliant behavior in the HTTP client.

Why? Your explanation is invalid because it implicates dirmngr's HTTP client as not comforming to the spec laid out by the RFC. I've quite clearly explained--and backed up with the spec itself--that when a proxy variable is configured, a client should not be doing DNS lookup of the destination hostname. Is there something about that you are not understanding?

Please show an example regarding something else than a failed access to a pool of keyservers. I explained why it can't work for pools for you.

Yes you can, and no you do not. Don't believe me? Then read the spec. At no point does the spec say that there is "nothing that can be done" when a hostname cannot be resolved when connecting through a proxy. In fact, it states precisely the opposite, describing the exact procedure a client should take when making a request through a proxy. See section 5.3, paragraph 3:

No we can't we need to know the IP addresses to handle the pools. I have given a workaround for you in my previous comment. You can also use install Tor which we can use for DNS resolving.

So if your DNS resolver does not tell us the IP addresses, we can't do anything about it.

If you specify a pool of keyservers dirmngr selects a keyserver on its won from the pool. This is so that it can use its own heuristics to detect whether a keyserver is dead and then retry another one. Now the default is a pool and your specified keyserver.ubuntu.com is also a pool (of two servers). So if your DNS resolver does not tell us the IP addresses, we can't do anything about it.

It seems that this part of the code was not finished. Unfortunately upstream of the dns code is unresponsive and thus we started to maintain the code base by ourselves. There is still an open question whether we should do that to the full extend, in which case we would integrate the code closer into the GnuPG framework with its own logging subsystems.

A workaround for this until the HTTP client is fixed is to just use curl instead:

I am running into the same exact issue. It seems that dirmng is incorrectly attempting to resolve the addresses for the keyservers despite having been given an HTTP proxy to connect through.

Applied to 2.2 branch.

And 2.2 branch.

Fixed in master.

I'll fix for the non-FQDN case.

I think that I identified the issue. This is the libdns (dirmngr/dns.c) problem when hostname is not FQDN.
If you change it to FQDN, you can see that it tries to search adding the domain name.

Fixed in master.

It is indirectly reported at the upstream: https://github.com/wahern/dns/issues/19

An option to ignore SRV records would also be good for debugging. Thus I raised the priority and truned this into a feature request.

@Beiri22: It was my fault to to tell you to use scdaemon.conf. The correct conf file is of course dirmngr.conf. However, with @BenM comments I don't think that it is a bug at all. I am thus closing this; please feel free to re-open if we were wrong