Estou enviando um pacote UDP do Arduino, o pacote chega ao meu servidor Ubuntu porque é possível vê-lo no tcpdump como você pode ver. Mas nunca é encaminhado para o meu aplicativo que está escutando na porta 8888. Alguém tem uma ideia do que está errado no pacote?
Minha versão do Ubuntu é: Ubuntu 12.04.1 LTS (GNU / Linux 3.2.0-29-genérico-pae i686)
Este é o tcpdump :
tcpdump -i 1 udp port 8888 -vv -X
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 65535 byte s
19:06:20.179117 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP (17), length 131)
192.168.1.53.3333 > diskServer.8888: [udp sum ok] UDP, length 103
0x0000: 4500 0083 0000 4000 4011 b6b1 c0a8 0135 E.....@[email protected]
0x0010: c0a8 0133 0d05 22b8 006f 87d6 7465 7374 ...3.."..o..test
0x0020: 2030 3132 3334 3536 3738 3930 2074 6573 .01234567890.tes
0x0030: 7420 3031 3233 3435 3637 3839 3020 7465 t.01234567890.te
0x0040: 7374 2030 3132 3334 3536 3738 3930 2074 st.01234567890.t
0x0050: 6573 7420 3031 3233 3435 3637 3839 3020 est.01234567890.
0x0060: 7465 7374 2030 3132 3334 3536 3738 3930 test.01234567890
0x0070: 2074 6573 7420 3031 3233 3435 3637 3839 .test.0123456789
0x0080: 3020 00 0..
Esta é a porta de escuta:
root@diskServer:~# netstat -a
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 diskServer:mysql *:* LISTEN
tcp 0 0 *:netbios-ssn *:* LISTEN
tcp 0 0 *:ssh *:* LISTEN
tcp 0 0 *:https *:* LISTEN
tcp 0 0 *:microsoft-ds *:* LISTEN
tcp 0 0 diskServer:ssh flavix:53077 ESTABLISHED
tcp 0 144 diskServer:ssh flavix:53028 ESTABLISHED
tcp 0 0 diskServer:ssh 192.168.1.107:54978 ESTABLISHED
tcp 0 0 diskServer:ssh 192.168.1.107:55000 ESTABLISHED
tcp6 0 0 [::]:8009 [::]:* LISTEN
tcp6 0 0 [::]:http-alt [::]:* LISTEN
tcp6 0 0 [::]:ssh [::]:* LISTEN
tcp6 0 0 [::]:8443 [::]:* LISTEN
tcp6 0 0 localhost:8005 [::]:* LISTEN
udp 0 0 diskServer:ntp *:*
udp 0 0 localhost:ntp *:*
udp 0 0 *:ntp *:*
udp 0 0 192.168.1.25:netbios-ns *:*
udp 0 0 diskServer:netbios-ns *:*
udp 0 0 *:netbios-ns *:*
udp 0 0 192.168.1.2:netbios-dgm *:*
udp 0 0 diskServer:netbios-dgm *:*
udp 0 0 *:netbios-dgm *:*
udp 0 0 diskServer:8888 *:***
udp6 0 0 ip6-localhost:ntp [::]:*
udp6 0 0 fe80::20e:7bff:feac:ntp [::]:*
udp6 0 0 [::]:ntp [::]:*
Memória do UDP:
root@diskServer:~# cat /proc/sys/net/ipv4/udp_mem
18066 24090 36132
root@diskServer:~# netstat -su
IcmpMsg:
InType3: 10316969
InType8: 18368
OutType0: 18368
OutType3: 10317030
Udp:
211263 packets received
10309092 packets to unknown port received.
0 packet receive errors
10348446 packets sent
UdpLite:
IpExt:
InMcastPkts: 24678
InBcastPkts: 287164
OutBcastPkts: 12685
InOctets: -1
OutOctets: -1
InMcastOctets: 690984
InBcastOctets: 48281994
OutBcastOctets: 3170039
root@diskServer:~# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
fail2ban-apache-badbots tcp -- anywhere anywhere multiport dports http,https
fail2ban-apache-overflows tcp -- anywhere anywhere multiport dports http,https
fail2ban-apache-noscript tcp -- anywhere anywhere multiport dports http,https
fail2ban-apache tcp -- anywhere anywhere multiport dports http,https
fail2ban-ssh tcp -- anywhere anywhere multiport dports ssh
ufw-before-logging-input all -- anywhere anywhere
ufw-before-input all -- anywhere anywhere
ufw-after-input all -- anywhere anywhere
ufw-after-logging-input all -- anywhere anywhere
ufw-reject-input all -- anywhere anywhere
ufw-track-input all -- anywhere anywhere
Chain FORWARD (policy ACCEPT)
target prot opt source destination
ufw-before-logging-forward all -- anywhere anywhere
ufw-before-forward all -- anywhere anywhere
ufw-after-forward all -- anywhere anywhere
ufw-after-logging-forward all -- anywhere anywhere
ufw-reject-forward all -- anywhere anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
ufw-before-logging-output all -- anywhere anywhere
ufw-before-output all -- anywhere anywhere
ufw-after-output all -- anywhere anywhere
ufw-after-logging-output all -- anywhere anywhere
ufw-reject-output all -- anywhere anywhere
ufw-track-output all -- anywhere anywhere
Chain fail2ban-apache (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-apache-badbots (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-apache-noscript (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-apache-overflows (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-ssh (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain ufw-after-forward (1 references)
target prot opt source destination
Chain ufw-after-input (1 references)
target prot opt source destination
Chain ufw-after-logging-forward (1 references)
target prot opt source destination
Chain ufw-after-logging-input (1 references)
target prot opt source destination
Chain ufw-after-logging-output (1 references)
target prot opt source destination
Chain ufw-after-output (1 references)
target prot opt source destination
Chain ufw-before-forward (1 references)
target prot opt source destination
Chain ufw-before-input (1 references)
target prot opt source destination
Chain ufw-before-logging-forward (1 references)
target prot opt source destination
Chain ufw-before-logging-input (1 references)
target prot opt source destination
Chain ufw-before-logging-output (1 references)
target prot opt source destination
Chain ufw-before-output (1 references)
target prot opt source destination
Chain ufw-reject-forward (1 references)
target prot opt source destination
Chain ufw-reject-input (1 references)
target prot opt source destination
Chain ufw-reject-output (1 references)
target prot opt source destination
Chain ufw-track-input (1 references)
target prot opt source destination
Chain ufw-track-output (1 references)
target prot opt source destination
ufw está desativado.
O problema estava no pacote, isso está errado porque o destino no nível Ethernet foi definido como 0, esta é a saída de wireShark:
Ethernet II, Src: 74: 69: 69: 2d: 30: 31 (74: 69: 69: 2d: 30: 31), Dst: 00: 00: 00_00: 00: 00 (00:00:00 : 00: 00: 00)
Isso se deve a um problema de hardware na minha placa Arduino.
Thaks para todos, Ciao.
O problema real está provavelmente na biblioteca ethercard usada. Ele não manipula corretamente a pesquisa ARP para o destino, causando o endereço MAC de destino de todos os zeros (consulte link ).
Uma biblioteca alternativa que funciona é a Ethernet_UIP, que pode ser encontrada no link e que tem um exemplo que envia pacotes UDP; Eu testei esse exemplo e ele funciona.