Can't send Scapy packet over a raw socket in p

问题:

A simple client-server raw socket where the client send a custom packet and it will be received from the server.

Here's my code.

Client.py

#!/usr/bin/env python

import socket
import sys
from scapy.all import *


sock = socket.socket(socket.AF_PACKET, socket.SOCK_RAW)

try: 
    a=Ether(dst="90:**:**:**:**:75", src="90:**:**:**:**:96")/IP(src="192.168.240.5", dst="192.168.240.1")/TCP(sport=10000,dport=10000)/"HELLO"
a.show()

sendp(a)


finally:
    print >>sys.stderr, 'closing socket'
    sock.close()

Output:

###[ Ethernet ]###
dst       = 90:**:**:**:**:75
src       = 90:**:**:**:**:96
type      = 0x800
###[ IP ]###
 version   = 4
 ihl       = None
 tos       = 0x0
 len       = None
 id        = 1
 flags     = 
 frag      = 0
 ttl       = 64
 proto     = tcp
 chksum    = None
 src       = 192.168.240.5
 dst       = 192.168.240.1
 \options   \
###[ TCP ]###
    sport     = 10000
    dport     = 10000
    seq       = 0
    ack       = 0
    dataofs   = None
    reserved  = 0
    flags     = S
    window    = 8192
    chksum    = None
    urgptr    = 0
    options   = {}
###[ Raw ]###
       load      = 'HELLO'
.
Sent 1 packets.
closing socket

Server.py

#!/usr/bin/env python

import socket
import sys
from scapy.all import *

sock = socket.socket(socket.AF_PACKET, socket.SOCK_RAW)
sock.bind(("wlan0",10000))

def pkt_callback(pkt):
    pkt.show() # debug statement


while True:
     print >>sys.stderr, 'waiting for a connection'

     sniff(iface="wlan0", prn=pkt_callback, store=0)

The server shows me every packets it intercepts but there's no sign of the one sent by the client.py script. I guess it is not sent at all.

What is the problem?