OpenThread COAP Client to a public server over Internet

RE: OpenThread COAP Client to a public server over Internet

SebastianCorin — Sat, 21 Oct 2023 20:17:09 GMT

bool SynthesizeIpv4ToIpv6Adress(char ip_str[], struct in6_addr *ipv6_addr)
{
	uint8_t ipv4_bytes[4];

    char *token = strtok(ip_str, ".");
    for (int i = 0; i < 4; i++) {
        ipv4_bytes[i] = atoi(token);
        token = strtok(NULL, ".");
    }
	int i;
	otIp4Address tmp_ipv4_addr;
	otIp6Address synt_ipv6_addr;

	for (i = 0; i < 4; i++)
	{
		tmp_ipv4_addr.mFields.m8[i] = ipv4_bytes[i];
	}

	if (OT_ERROR_NONE != otNat64SynthesizeIp6Address(
							 instance,
							 (const otIp4Address *)&tmp_ipv4_addr,
							 &synt_ipv6_addr))
	{
		LOG_INF("ERROR otNat64SynthesizeIp6Address() function!");
		return false;
	}
	for (i = 0; i < 16; i++)
	{
		ipv6_addr->s6_addr[i] = synt_ipv6_addr.mFields.m8[i];
	}

	return true;
}

and calling the function with:

struct sockaddr_in6 addr6 = {
		.sin6_family = AF_INET6,
		.sin6_port = htons(COAP_DEFAULT_PORT),
		.sin6_addr.s6_addr = {
			0,
		},
		.sin6_scope_id = 0U};
	
	SynthesizeIpv4ToIpv6Adress("192.168.178.157", &addr6.sin6_addr);

RE: OpenThread COAP Client to a public server over Internet

ArunRuchir — Sat, 19 Aug 2023 11:57:11 GMT

Thanks Marco,

Since I am a beginner, pls also help which header files are required and how to define all variables.

Also - where do I give my OTBR IPv4 address in this?

Thanks in advance for your help.

Regards

Arun

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Fri, 18 Aug 2023 08:40:53 GMT

Hi Arun, I can't share my code for contract reasons as I am working for a customer of mine. Anyway the source code shared above Charlie is still available and it is what I based my application on. However I am using IPv6 address as I could not make it work on IPv4 as you need. So I suggest you to obtain the IPv6 address from the server IPv4 one.

bool COMM_getIpv6Address( uint8_t *ipv4_addr, struct in6_addr *ipv6_addr )
{
int i;
otIp4Address tmp_ipv4_addr;
otIp6Address synt_ipv6_addr;
struct openthread_context *ot = ot_context;

for (i=0; i<4; i++)
{
tmp_ipv4_addr.mFields.m8[i] = ipv4_addr[i];
}

if (OT_ERROR_NONE != otNat64SynthesizeIp6Address(
ot->instance,
(const otIp4Address *)&tmp_ipv4_addr,
&synt_ipv6_addr))
{
LOG_ERR("ERROR otNat64SynthesizeIp6Address() function!");
return false;
}

for (i=0; i<16; i++)
{
ipv6_addr->s6_addr[i] = synt_ipv6_addr.mFields.m8[i];
}

return true;
}

The Border Router must have the NAT64 (or equivalent) enabled and I think that latest OpenThread Border Router release has it already enabled by default.

I hope it helps.

Cheers.

Marco

RE: OpenThread COAP Client to a public server over Internet

ArunRuchir — Fri, 18 Aug 2023 07:32:33 GMT

Hi Marco and/or Charlie,

Thanks for this thread. I am also trying the same - CoAP Client to CoAP server running in OTBR (Raspberry pi) at Ipv4 side for internet view. I am also trying to get data via UART into CoAP-client and then send it to CoAP-Server in OTBR. Facing many issues.

If you can share your codes and/or link to your codes, it will be helpful.

Thanks in advance.

Arun

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Fri, 16 Dec 2022 09:40:33 GMT

Hi Charlie,

I tried the code shared by your developer and it works fine! I do not know what the difference is with my original code so I'll look into it. Anyway I guess I can consider this issue solved for now.

Thank you for your help.

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Wed, 14 Dec 2022 16:41:56 GMT

Hi Charlie,

yes the CLI command works fine. The sample code you provided does exactly what I am trying to do. It looks the same of my code but I am gonna try it out to see if that works in my environment.

I'll let you know.

Thanks.

RE: OpenThread COAP Client to a public server over Internet

Charlie — Wed, 14 Dec 2022 12:13:45 GMT

Hi Marco,

I still need to work on some issues with my OTBR.

If your CLI command "ot coap get 64:ff9b:0:0:0:0:8666:da12 hello" works on your setup, you can test with the following coap client sample provided by our developer: GitHub - canisLupus1313/ot-sensor.

It basically send "hello" GET request to coap.me and prints out the reply "world". Please remember to modify the following configuration to join your OTBR-formed thread network.

CONFIG_OPENTHREAD_NETWORKKEY="00:11:22:33:44:55:66:77:88:99:aa:bb:cc:dd:ee:ff"
CONFIG_OPENTHREAD_NETWORK_NAME="OpenThread-7cf7"
CONFIG_OPENTHREAD_XPANID="3b:78:ce:62:9c:bc:8e:23"
CONFIG_OPENTHREAD_PANID=31991

Best regards,

Charlie

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Tue, 13 Dec 2022 16:13:39 GMT

Thank you Charlie for the update. I will prepare the sniffer and start debugging what I can.

I'll be waiting for a following update from you or your colleagues.

Cheers.

Marco

RE: OpenThread COAP Client to a public server over Internet

Charlie — Tue, 13 Dec 2022 14:50:35 GMT

Hi Marco,

Thanks for the update, I have tested with the NCS2.2.0 OT sample and experienced a similar issue as you now, not able to find the cause.

I have requested our development team to debug this issue together and will give you feedback if we find something.

We may request a sniffer recording for your test later, please prepare to set up Sniffer for 802.15.4.

Best regards,

Charlie

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Mon, 12 Dec 2022 15:06:06 GMT

Hi Charlie I just want to let you know that I have the same problem with the OT APIs directly. I can't even ping a remote server.

I have attached my new source code.

Cheers.devzone.nordicsemi.com/.../7357.coap_5F00_client_5F00_utils.c

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Thu, 08 Dec 2022 08:47:24 GMT

Ah OK, no problem, I just wanted to know if it was my problem only or not. Let me know if I can help you on this by trying something...

Thank you very much for your help!

Marco

RE: OpenThread COAP Client to a public server over Internet

Charlie — Thu, 08 Dec 2022 07:18:39 GMT

Hi Marco，

Sorry for the late reply. I can repeat your issue, need a bit more time to debug the issue plus traveling.

I will try to give you a reply next week. Is this OK for you?

Best regards,

Charlie

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Wed, 07 Dec 2022 14:52:59 GMT

Charlie any update please?

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Mon, 05 Dec 2022 17:13:54 GMT

FYI the IPV6 destination address is the well-known prefix 64:ff9b:: (as mentioned above) added to 0x86, 0x66, 0xda, 0x12 which is IPV4 134.102.218.18 (coap.me).

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Mon, 05 Dec 2022 16:49:48 GMT

I did some code clean up and launched the program again to capture the log for you.

The behaviour is the same. Looks like the UDP frame is sent and received back without going out. I have disabled 802.15.4 frames log but let me know if you want me to capture again with that enabled. For now only IPV6 log is enabled.

I also had to increase the coap thread stack size in coap_utils.c (nrf/subsys/net/lib/coap_util).

I had to rename the .conf file to .txtdevzone.nordicsemi.com/.../overlay_2D00_logging.txt devzone.nordicsemi.com/.../0250.prj.txt

Steps from the log:

1) I launch the program

2) start commissioning on the border router

3) press button 1 to join the thread network with assigned passphrase

4) press button 2 to send a message (COAP GET)

devzone.nordicsemi.com/.../log01.txt

devzone.nordicsemi.com/.../0334.coap_5F00_client.c devzone.nordicsemi.com/.../3566.coap_5F00_client_5F00_utils.c devzone.nordicsemi.com/.../coap_5F00_utils.c

RE: OpenThread COAP Client to a public server over Internet

Charlie — Mon, 05 Dec 2022 15:43:13 GMT

Hi Marco,

Sorry, I understand what you mean now. Could you share your modification to the CoAP client sample and log during running?

The reason is to demonstrate developers different CoAP API options they can use for the development, but Zephyr’s CoAP API is the encouraged option.

Best regards,

Charlie

RE: OpenThread COAP Client to a public server over Internet

Marco Russi — Mon, 05 Dec 2022 14:53:29 GMT

Yes, as I said the CLI sample works fine with coap.me and I can also ping google and other external servers. It has to do with the CoAp Client sample only. I have also tested Matter samples so I have quite confidence with the border router and related experiments.

I have turned all the debug log on and I am going to scrap the original implementation of the client and use the OpenThread API directly like in the CoAp Server sample. I wonder why Nordic provide the Client and Server samples implemented in two different ways: the Client with Zephyr CoAp APIs and the Server with OT (OpenThread) APIs. Any known reason? Thank you.

RE: OpenThread COAP Client to a public server over Internet

Charlie — Mon, 05 Dec 2022 13:21:32 GMT

Hi Marco,

Did you try the ping test mentioned Test Connectivity | OpenThread to verify if your NAT64 configuration works?

Best regards,

Charlie