我正在使用 Contiki 创建一个物联网产品,其中涉及多个基于 STM32L152 的节点和一个 Linux 板。我有一个嵌入式 Linux 板(基于 iMX6),它从节点接收数据,使用蜂窝网络发送到互联网,还有 10 个节点可以感知不同的环境参数并传送到 Linux 板。 Linux 板有一个运行边界/边缘路由器代码的协处理器,该协处理器的 UART2 线连接到 Linux 板。我使用 Contiki 工具 tunslip6 创建 tun0 接口(interface),我能够 ping 每个节点。
为了使问题更容易理解,我将解释我执行的硬件设置和步骤。
这样做之后;
sudo ./tunslip6 –s /dev/ttyACM0 aaaa::1/64
,我可以看到网页上的所有邻居节点,我也可以ping6每个节点。我想在 Linux 上编写应用程序代码来接收和发送数据到每个节点,我被困在这一点上。
sudo ./tunslip6 -s /dev/ttyACM0 aaaa::1/64
********SLIP started on ``/dev/ttyACM0''
opened tun device ``/dev/tun0''
ifconfig tun0 inet `hostname` mtu 1500 up
ifconfig tun0 add aaaa::1/64
ifconfig tun0 add fe80::0:0:0:1/64
ifconfig tun0
tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-
00-00-00-00-00
inet addr:127.0.1.1 P-t-P:127.0.1.1 Mask:255.255.255.255
inet6 addr: fe80::1/64 Scope:Link
inet6 addr: aaaa::1/64 Scope:Global
inet6 addr: fe80::8fad:d1a:c8d0:b76f/64 Scope:Link
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
*** Address:aaaa::1 => aaaa:0000:0000:0000
Got configuration message of type P
Setting prefix aaaa::
Server IPv6 addresses:
aaaa::900:f4ff:c3a:f3c5
fe80::900:f4ff:c3a:f3c5
ifconfig
tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:127.0.1.1 P-t-P:127.0.1.1 Mask:255.255.255.255
inet6 addr: fe80::1/64 Scope:Link
inet6 addr: aaaa::1/64 Scope:Global
inet6 addr: fe80::8fad:d1a:c8d0:b76f/64 Scope:Link
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:37 errors:0 dropped:0 overruns:0 frame:0
TX packets:67 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:3422 (3.4 KB) TX bytes:5653 (5.6 KB)
ip addr show tun0
3: tun0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 500
link/none
inet 127.0.1.1/32 scope host tun0
valid_lft forever preferred_lft forever
inet6 aaaa::1/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::1/64 scope link
valid_lft forever preferred_lft forever
inet6 fe80::8fad:d1a:c8d0:b76f/64 scope link flags 800
valid_lft forever preferred_lft forever
sudo ip -6 route
aaaa::/64 dev tun0 proto kernel metric 256 pref medium
fe80::/64 dev tun0 proto kernel metric 256 pref medium
This is what I am seeing on the webpage, I have one neighbor node我可以ping通这个。
ping6 aaaa::fdff:d2fa:2d05
PING aaaa::fdff:d2fa:2d05(aaaa::fdff:d2fa:2d05) 56 data bytes
64 bytes from aaaa::fdff:d2fa:2d05: icmp_seq=1 ttl=63 time=130 ms
64 bytes from aaaa::fdff:d2fa:2d05: icmp_seq=2 ttl=63 time=131 ms
64 bytes from aaaa::fdff:d2fa:2d05: icmp_seq=3 ttl=63 time=130 ms
64 bytes from aaaa::fdff:d2fa:2d05: icmp_seq=4 ttl=63 time=130 ms
64 bytes from aaaa::fdff:d2fa:2d05: icmp_seq=6 ttl=63 time=130 ms
64 bytes from aaaa::fdff:d2fa:2d05: icmp_seq=7 ttl=63 time=130 ms
64 bytes from aaaa::fdff:d2fa:2d05: icmp_seq=8 ttl=63 time=131 ms
^C
--- aaaa::fdff:d2fa:2d05 ping statistics ---
8 packets transmitted, 7 received, 12% packet loss, time 7040ms
rtt min/avg/max/mdev = 130.681/131.068/131.863/0.555 ms
我不是网络和套接字编程方面的专家,我写了一些我在互联网上找到并尝试过的代码。我尝试过这样的事情;
import socket
UDP_IP = "aaaa::fdff:d2fa:2d05"
UDP_PORT = 1234
print "UDP target IP:", UDP_IP
print "UDP target port:", UDP_PORT
sock = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM) # UDP
sock.connect((UDP_IP, UDP_PORT))
while True:
data = sock.recv(1024)
print 'Received', repr(data)
问题:在 Linux 用户空间,我的同事想写一个可以读写每个节点的应用程序代码(本例为
aaaa::fdff:d2fa:2d05
),如何实现?在微 Controller 板上,我可以使用两个节点进行读写,但不能在 Linux 空间中。请帮助我,如何从Linux用户空间读取数据并将数据写入每个节点?如果可能,请分享一些示例代码。谢谢!更新 - 我尝试使用不同的 Contiki 示例在 Linux 主机和节点之间进行通信,contiki/examples/ipv6/rpl-udp/udp-client.c 并取得了成功,我能够从节点接收数据。我的python代码是;
import socket, struct
UDP_LOCAL_IP = 'aaaa::1'
UDP_LOCAL_PORT = 5678
UDP_REMOTE_IP = 'fe80::fdff:d2fa:2d05'
UDP_REMOTE_PORT = 8765
try:
socket_rx = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
socket_rx.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
socket_rx.bind((UDP_LOCAL_IP, UDP_LOCAL_PORT))
except Exception:
print "ERROR: Server Port Binding Failed"
print 'UDP server ready: %s'% UDP_LOCAL_PORT
print
while True:
data, addr = socket_rx.recvfrom(1024)
print "address : ", addr
print "received message: ", data
print "\n"
socket_rx.sendto("Hello from serevr\n", (UDP_REMOTE_IP, UDP_REMOTE_PORT))
上面的python代码正在工作。
最佳答案
根据 https://anrg.usc.edu/contiki/index.php/RPL_Border_Router,边界路由器有一个硬编码的 IPv6 地址。这个地址是fe80:0000:0000:0000:0212:7401:0001:0101
(可能运行 ip addr show tun0
-> 您的编辑显示分配的地址是 fe80:0000:0000:0000:8fad:d1a:c8d0:b76f
)。将应用程序的套接字绑定(bind)到此地址,在 python 中没有此代码。因为你使用 tunslip
您还可以使用准确的端口和 ipv4 协议(protocol)绑定(bind)到 localhost
对于测试,您可以使用 netcat
将 UDP 数据包直接发送到节点 (http://www.tutorialspoint.com/unix_commands/nc.htm)
要摆脱错误(注释),您必须申请 inet_pton
用于转换 IPv6 地址 ( http://man7.org/linux/man-pages/man3/inet_pton.3.html )
以下是可以转换为 python 的工作 C 代码。为使用 Raven USB 内存棒作为边界路由器而编写(搜索 Contiki Jackdaw,未使用 tunslip)
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <net/if.h>
int fd = 0; //socket file descriptor
struct sockaddr_in6 server;
/* ipv6 address to in6_addr structure */
const char *ip6str = "fe80::8fad:d1a:c8d0:b76f";
struct in6_addr ravenipv6;
if (inet_pton(AF_INET6, ip6str, &ravenipv6) == 1) // successful
{
printf("%s \n", "ipv6 address ...");
}
/* Create an empty IPv6 socket interface specification */
memset(&server, 0, sizeof(server));
server.sin6_family = AF_INET6;
server.sin6_flowinfo = 0;
server.sin6_port = htons(1234); // port
server.sin6_addr = ravenipv6; <- here the address converted with inet_ptons is inserted
server.sin6_scope_id = if_nametoindex("tun0"); // if your border router is on tun0
/*create socket*/
if ((fd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) == -1)
{
printf("%s \n", "failed to create socket");
}
/*bind to socket*/
if(bind(fd, (struct sockaddr_in6*)&server, sizeof(server)) == -1)
{
printf("%s \n", "no binding ! ");
}
关于sockets - Linux 用户空间代码,用于在 Linux 板和运行 contiki udp 发送器示例代码的每个节点之间进行通信,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/52900177/