From wouter at nlnetlabs.nl  Mon Aug  1 14:24:47 2016
From: wouter at nlnetlabs.nl (W.C.A. Wijngaards)
Date: Mon, 1 Aug 2016 16:24:47 +0200
Subject: [ldns-users] Are there send() and recv()-like interfaces in
 libdns?
In-Reply-To: <CAF8xhAuRksa2Mrnsmymi-b2fPM=oHSE=UcJhBs_szqpAT2Joqg@mail.gmail.com>
References: <CAF8xhAuRksa2Mrnsmymi-b2fPM=oHSE=UcJhBs_szqpAT2Joqg@mail.gmail.com>
Message-ID: <2d2610db-223e-4755-5daa-76d450c24911@nlnetlabs.nl>

Hi Dami?o,

There are the functions ldns_udp_bgsend() that returns a socket on which
the send() has been performed.  And ldns_udp_read_wire() when you want
the result.  From ldns/net.h.  (there are also tcp versions).

The functions ldns_rdf2native_sockaddr_storage and
ldns_sockaddr_storage2rdf can help you convert A (and AAAA) rdfs to the
sockaddr struct that the routines want.

Best regards, Wouter

On 31/07/16 23:04, Dami?o Rodrigues wrote:
> I've built a simple command line application in C which uses libdns to
> make periodic DNS queries to the authoritative name servers of multiple
> domains. Ensuring the periodicity of the queries is important, following
> a user-defined query_interval (in seconds). 
> 
> As far as I could tell, libdns only allows for request-response calls:
> the functions which start DNS queries also return the DNS response,
> blocking until a response is received. Because of this, I've implemented
> a key part of the application in a naive way within a while() cycle: 
> 
>  1. I do a block of queries
>  2. Take note of the time taken by the query block (query_time)
>  3. sleep(query_interval - query_time)
>  4. Go back to 1 
> 
> I think this is sloppy. A better option would be to have separate
> send/receive threads. This way, the periodicity of the query blocks
> wouldn't be affected by the duration of the request-response cycles. But
> for that I would need libdns functions with separate send()- and
> recv()-like interfaces, which I couldn't find in the documentation,
> greps in the source folders, nor examples. 
> 
> Have I missed something? *Are there send()- and recv()-like interfaces
> in libdns?*
> *
> *
> Thanks in advance!
> 
> Best regards,
> Antonio
> *
> *
> 
> 
> _______________________________________________
> ldns-users mailing list
> ldns-users at open.nlnetlabs.nl
> https://open.nlnetlabs.nl/mailman/listinfo/ldns-users
> 


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From adamiaonr at gmail.com  Mon Aug  1 14:48:00 2016
From: adamiaonr at gmail.com (=?UTF-8?Q?Dami=C3=A3o_Rodrigues?=)
Date: Mon, 1 Aug 2016 16:48:00 +0200
Subject: [ldns-users] Are there send() and recv()-like interfaces in
	libdns?
In-Reply-To: <2d2610db-223e-4755-5daa-76d450c24911@nlnetlabs.nl>
References: <CAF8xhAuRksa2Mrnsmymi-b2fPM=oHSE=UcJhBs_szqpAT2Joqg@mail.gmail.com>
 <2d2610db-223e-4755-5daa-76d450c24911@nlnetlabs.nl>
Message-ID: <CAF8xhAv=4umZrCYFJhEqeWE7Va-jP9UbF26mahpp=rGCMR430w@mail.gmail.com>

Hi Wouter,

Thank you for the tip, this is close to what I'm looking for.

I have a couple of follow-up observations/questions:

   - Let's say I would go ahead with the separate read/write thread
   pattern. Since ldns_udp_bgsend() would update the socket file descriptor to
   be subsequently used by ldns_udp_read_wire(), for every individual call, I
   would have to keep a shared list of file descriptors, shared between the
   threads. This list would be written to by the ldns_udp_bgsend(), read by
   the ldns_udp_read_wire().
   - In your experience with libdns, did you ever had to implement
   something like this (separate read/write threads)? If yes, Is the method
   described above the one that you've followed to accomplish it? If not, what
   method did you use?

Thank you once more Wouter!

Best regards,

Dami?o

On Mon, Aug 1, 2016 at 4:24 PM, W.C.A. Wijngaards <wouter at nlnetlabs.nl>
wrote:

> Hi Dami?o,
>
> There are the functions ldns_udp_bgsend() that returns a socket on which
> the send() has been performed.  And ldns_udp_read_wire() when you want
> the result.  From ldns/net.h.  (there are also tcp versions).
>
> The functions ldns_rdf2native_sockaddr_storage and
> ldns_sockaddr_storage2rdf can help you convert A (and AAAA) rdfs to the
> sockaddr struct that the routines want.
>
> Best regards, Wouter
>
> On 31/07/16 23:04, Dami?o Rodrigues wrote:
> > I've built a simple command line application in C which uses libdns to
> > make periodic DNS queries to the authoritative name servers of multiple
> > domains. Ensuring the periodicity of the queries is important, following
> > a user-defined query_interval (in seconds).
> >
> > As far as I could tell, libdns only allows for request-response calls:
> > the functions which start DNS queries also return the DNS response,
> > blocking until a response is received. Because of this, I've implemented
> > a key part of the application in a naive way within a while() cycle:
> >
> >  1. I do a block of queries
> >  2. Take note of the time taken by the query block (query_time)
> >  3. sleep(query_interval - query_time)
> >  4. Go back to 1
> >
> > I think this is sloppy. A better option would be to have separate
> > send/receive threads. This way, the periodicity of the query blocks
> > wouldn't be affected by the duration of the request-response cycles. But
> > for that I would need libdns functions with separate send()- and
> > recv()-like interfaces, which I couldn't find in the documentation,
> > greps in the source folders, nor examples.
> >
> > Have I missed something? *Are there send()- and recv()-like interfaces
> > in libdns?*
> > *
> > *
> > Thanks in advance!
> >
> > Best regards,
> > Antonio
> > *
> > *
> >
> >
> > _______________________________________________
> > ldns-users mailing list
> > ldns-users at open.nlnetlabs.nl
> > https://open.nlnetlabs.nl/mailman/listinfo/ldns-users
> >
>
>
>
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From scott-nlnetlabs at shambarger.net  Sat Aug 20 17:15:00 2016
From: scott-nlnetlabs at shambarger.net (Scott Shambarger)
Date: Sat, 20 Aug 2016 19:15:00 +0200
Subject: [ldns-users] Proposed new api to load build-time configured trust
	anchors
Message-ID: <85ec0dc9dd1b03b35dcf9029079d24f0@shambarger.net>

I've been trying to get openssh to locally validate SSHFP records on 
OSX.

The problem stems from the fact that OSX's configd rewrites 
/etc/resolv.conf each time the network changes (think connecting to a 
coffee shop's wifi).  Openssh (configured with ldns) connections will 
then query the SSHFP record, but as the trust anchors are not referenced 
in resolv.conf, it is unable to perform DNSSEC validation.

Openssh maintainers don't feel that trust-anchor loading is in their 
scope of responsibility, and feel the ldns interface should work "out of 
the box" (see Comment#1 at 
https://bugzilla.mindrot.org/show_bug.cgi?id=2119)

I submitted a patch to add a new api to libldns to load keys from 
build-time defined locations (by default $sysconfdir/trusted-key.key and 
$sysconfdir/unbound/root.key), in 
https://www.nlnetlabs.nl/bugs-script/show_bug.cgi?id=727 -- however, 
there hasn't been any feedback on the proposal for 8 months...

I added a new api as drill (and possibly other users) may want to load 
their own trust anchors and not have any loaded by default; however 
users such as openssh do want validation to work without adding their 
own anchor files.

The root of the problem is still OSX, as other platforms can just add 
the "anchor" key to /etc/resolv.conf (but edits are wiped repeatedly on 
OSX).

I'd love to hear if anyone has a better solution though :)

Thanks,
Scott



From vladimir.levijev at gmail.com  Mon Aug 29 10:30:26 2016
From: vladimir.levijev at gmail.com (Vladimir Levijev)
Date: Mon, 29 Aug 2016 13:30:26 +0300
Subject: [ldns-users] Small ldns_resolver_send() header fix
Message-ID: <CAAn0BQZW7cVyjaRBVd9QHzVa-7=C8yfPsSzRJaWc2YzX6PxadA@mail.gmail.com>

Hi,

Sorry for possibly sending it to the wrong place. Noticed this small
error in the description of ldns_resolver_send() function.

Cheers,

VL
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From jamesraf at amazon.com  Mon Aug 29 11:42:38 2016
From: jamesraf at amazon.com (Raftery, James)
Date: Mon, 29 Aug 2016 11:42:38 +0000
Subject: [ldns-users] [PATCH] Python binding for ldns_pkt2wire()
Message-ID: <1472470965110.56688@amazon.com>

Hi,

The auto-generated binding for ldns_pkt2wire() doesn't work properly. Patch attached that fixes that, providing the same style of interface as ldns_wire2pkt()


Thanks,
james



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From christoph at christoph-egger.org  Tue Aug 30 15:06:46 2016
From: christoph at christoph-egger.org (Christoph Egger)
Date: Tue, 30 Aug 2016 17:06:46 +0200
Subject: [ldns-users] Python3 / ldns_wire2pkt
Message-ID: <874m621ek9.fsf@hepworth.siccegge.de>

Hi!

  For ldns.ldns_wire2pkt to work with Python3 one needs it to accept a
python byte object instead of a string. After a lot of fiddling around
the below patch seems to make it work. However iterationg [2] over rrs()
fails with [1] -- extracting the first one works fine.

[0]
--- ldns-1.6.17.orig/contrib/python/ldns.i
+++ ldns-1.6.17/contrib/python/ldns.i
@@ -132,12 +137,22 @@ uint32_t ldns_read_timeval_usec(struct t
 
 %apply uint32_t *OUTPUT { uint32_t *default_ttl};
 
+#define SWIG_PYTHON_STRICT_BYTE_CHAR
+
 // wire2pkt
-%apply (char *STRING, int LENGTH) { (const char *str, int len) };
+// %apply (char *STRING, int LENGTH) { (const char *str, int len) };
+
+%typemap(in) (const char* str,int len) (Py_ssize_t lenn) %{
+    if(PyBytes_AsStringAndSize($input,&$1,&lenn) == -1)
+        return NULL;
+    $2 = (int)lenn;
+%}
+

[1]
StopIteration

During handling of the above exception, another exception occurred:

SystemError: <built-in function _ldns_rr_list_deep_free> returned a result with an error set

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "./check_dnssec", line 107, in <module>
    sys.exit(main())
  File "./check_dnssec", line 104, in main
    check_synced(resolver, zone, args)
  File "./check_dnssec", line 62, in check_synced
    LDNS_SECTION_ANSWER).rrs())
SystemError: <built-in function _ldns_rr_free> returned a result with an error set

[2]
list(result.rr_list_by_type(RR_TYPE_SOA, LDNS_SECTION_ANSWER).rrs())
-- 
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