Re: [lwip-users] dhcp and mdns responder

[Manu Abraham]

Sorry, I missed the Wireshark capture bit attachment, in my reply.

Attached herein.

Thanks,

Manu

On Mon, Aug 31, 2020 at 1:08 AM Manu Abraham <abraham.manu@gmail.com> wrote:
>
> Replying to my own post:
>
> Attached wireshark capture screencap:
>
> The PC host 192.168.1.34 sends out a mDNS question.
>
> I was expecting that, the udp_recv() within
>
> /**
>  * @ingroup mdns
>  * Initiate MDNS responder. Will open UDP sockets on port 5353
>  */
> void
> mdns_resp_init(void)
>
> would be receiving the mDNS question. But in fact, it does not, when
> used in a mdns_example_init() from mdns_example.c context.
>
> So, I started looking to use udp_recv outside of mdns.c, but then the
> udp_pcb is static.
>
> static struct udp_pcb *mdns_pcb;
>
>
> Is something amiss in what I have understood ? Am I going on a wrong track ?
>
>
> Thanks for any pointers.
>
> Manu
>
>
>
> On Sun, Aug 30, 2020 at 10:10 PM Manu Abraham <abraham.manu@gmail.com> wrote:
> >
> > Greetings,
> >
> > Trying to get mdns from lwip/apps working.
> >
> > I have the following code running:
> >
> > void netpnp_thread(void *arg)
> > {
> >     struct netif *netif = arg;
> >
> >     xSemaphoreTake(sem_mdns, portMAX_DELAY);
> >     osDelay(1000);
> >
> >     igmp_report_groups(netif);
> >     mdns_example_init();
> >
> >     while (1);
> > }
> >
> >
> > With that mdns works with the mdns_example_init() shamelessly copied
> > from mdns_example.c, DHCP client has already created a multicast group
> > with address 224.0.0.1
> >
> > This is verified from the igmp debug log.
> >
> > My question is thus; How and when should an announcement be done ?
> > Does the browser application request the announcement request ?
> > If so, how should that be handled ?
> >
> >
> > Thanks,
> >
> > Manu
> >
> >
> >  (292) StartThread:
> > igmp_init: initializing
> >  (257) Netif_Config: Configuring Network
> > igmp_start: starting IGMP processing on if 24000234
> > igmp_lookup_group: allocated a new group with address 224.0.0.1 on if 
> > 24000234
> >  (342) dhcp_thread:
> >  DHCP state       : 132
> >  DHCP state       : SELECTING
> >  DHCP state       : CHECKING
> > igmp_report_groups: sending IGMP reports on if 24000234
> >  DHCP state       : BOUND
> >
> >  IPv4 Address     : 192.168.1.33
> >  IPv4 Subnet mask : 255.255.255.0
> >  IPv4 Gateway     : 192.168.1.1
> >
> >  Lease period: 86400s, Renew in: 43200s, Rebind in: 75600s
> >
> >  (330) print_dhcp_state: DHCP Bound
> > igmp_report_groups: sending IGMP reports on if 24000234
> > igmp_lookup_group: allocated a new group with address 224.0.0.251 on if 
> > 24000234
> > igmp_joingroup_netif: join to new group: 224.0.0.251
> > igmp_timeout: report membership for group with address 224.0.0.251 on
> > if 24000234
> > MDNS: Responding with A record
> > MDNS: Responding with SRV record
> > MDNS: Responding with TXT record
> > MDNS: Sending packet, len=106, unicast=0
> > MDNS: Responding with A record
> > MDNS: Responding with SRV record
> > MDNS: Responding with TXT record
> > MDNS: Sending packet, len=106, unicast=0
> > MDNS: Responding with A record
> > MDNS: Responding with SRV record
> > MDNS: Responding with TXT record
> > MDNS: Sending packet, len=106, unicast=0
> > MDNS: Responding with A record
> > MDNS: Responding with v4 PTR record
> > MDNS: Responding with service type PTR record
> > MDNS: Responding with service name PTR record
> > MDNS: Responding with SRV record
> > MDNS: Responding with TXT record
> > MDNS: Sending packet, len=184, unicast=0
> > mdns status[netif 0]: 1

Capture_01.PNG
Description: PNG image