pypacker
1.0.0
这是 Pypacker：Python 最快、最简单的数据包操作库。它允许您通过定义所有标头数据的各个方面来手动创建数据包，通过解析原始数据包字节来剖析数据包，在不同层上发送/接收数据包以及拦截数据包。
创建指定特定值的数据包或采用默认值：
from pypacker . layer3 . ip import IP
from pypacker . layer3 . icmp import ICMP
ip = IP ( src_s = "127.0.0.1" , dst_s = "192.168.0.1" , p = 1 ) +
ICMP ( type = 8 ) +
ICMP . Echo ( id = 123 , seq = 1 , body_bytes = b"foobar" )
# output packet
print ( "%s" % ip )
IP ( v_hl = 45 , tos = 0 , len = 2 A , id = 0 , off = 0 , ttl = 40 , p = 1 , sum = 3 B29 , src = b' x7f x00 x00 x01 ' , dst = b' xc0 xa8 x00 x01 ' , opts = [], handler = icmp )
ICMP ( type = 8 , code = 0 , sum = C03F , handler = echo )
Echo ( id = 7 B , seq = 1 , ts = 0 , bytes = b'foobar' )从文件（pcap/tcpdump 格式）读取数据包，分析并将其写回：
from pypacker import ppcap
from pypacker . layer12 import ethernet
from pypacker . layer3 import ip
from pypacker . layer4 import tcp
preader = ppcap . Reader ( filename = "packets_ether.pcap" )
pwriter = ppcap . Writer ( filename = "packets_ether_new.pcap" , linktype = ppcap . DLT_EN10MB )
for ts , buf in preader :
eth = ethernet . Ethernet ( buf )
if eth [ ethernet . Ethernet , ip . IP , tcp . TCP ] is not None :
print ( "%d: %s:%s -> %s:%s" % ( ts , eth [ ip . IP ]. src_s , eth [ tcp . TCP ]. sport ,
eth [ ip . IP ]. dst_s , eth [ tcp . TCP ]. dport ))
pwriter . write ( eth . bin ())
pwriter . close ()拦截（和修改）数据包，例如 MITM：
# Add iptables rule:
# iptables -I INPUT 1 -p icmp -j NFQUEUE --queue-balance 0:2
import time
from pypacker import interceptor
from pypacker . layer3 import ip , icmp
# ICMP Echo request intercepting
def verdict_cb ( ll_data , ll_proto_id , data , ctx ):
ip1 = ip . IP ( data )
icmp1 = ip1 [ icmp . ICMP ]
if icmp1 is None or icmp1 . type != icmp . ICMP_TYPE_ECHO_REQ :
return data , interceptor . NF_ACCEPT
echo1 = icmp1 [ icmp . ICMP . Echo ]
if echo1 is None :
return data , interceptor . NF_ACCEPT
pp_bts = b"PYPACKER"
print ( "changing ICMP echo request packet" )
echo1 . body_bytes = echo1 . body_bytes [: - len ( pp_bts )] + pp_bts
return ip1 . bin (), interceptor . NF_ACCEPT
ictor = interceptor . Interceptor ()
ictor . start ( verdict_cb , queue_ids = [ 0 , 1 , 2 ])
print ( "now sind a ICMP echo request to localhost: ping 127.0.0.1" )
time . sleep ( 999 )
ictor . stop ()发送和接收数据包：
# send/receive raw bytes
from pypacker import psocket
from pypacker . layer12 import ethernet
from pypacker . layer3 import ip
psock = psocket . SocketHndl ( mode = psocket . SocketHndl . MODE_LAYER_2 , timeout = 10 )
for raw_bytes in psock :
eth = ethernet . Ethernet ( raw_bytes )
print ( "Got packet: %r" % eth )
eth . reverse_address ()
eth . ip . reverse_address ()
psock . send ( eth . bin ())
# stop on first packet
break
psock . close () # send/receive using filter
from pypacker import psocket
from pypacker . layer3 import ip
from pypacker . layer4 import tcp
packet_ip = ip . IP ( src_s = "127.0.0.1" , dst_s = "127.0.0.1" ) + tcp . TCP ( dport = 80 )
psock = psocket . SocketHndl ( mode = psocket . SocketHndl . MODE_LAYER_3 , timeout = 10 )
def filter_pkt ( pkt ):
return pkt . ip . tcp . sport == 80
psock . send ( packet_ip . bin (), dst = packet_ip . dst_s )
pkts = psock . recvp ( filter_match_recv = filter_pkt )
for pkt in pkts :
print ( "got answer: %r" % pkt )
psock . close () # Send/receive based on source/destination data
from pypacker import psocket
from pypacker . layer3 import ip
from pypacker . layer4 import tcp
packet_ip = ip . IP ( src_s = "127.0.0.1" , dst_s = "127.0.0.1" ) + tcp . TCP ( dport = 80 )
psock = psocket . SocketHndl ( mode = psocket . SocketHndl . MODE_LAYER_3 , timeout = 10 )
packets = psock . sr ( packet_ip , max_packets_recv = 1 )
for p in packets :
print ( "got layer 3 packet: %s" % p )
psock . close ()一些例子：
请参阅示例/和测试/test_pypacker.py。
测试执行如下：
性能测试结果：pypacker
orC = Intel Core2 Duo CPU @ 1,866 GHz, 2GB RAM, CPython v3.6
orP = Intel Core2 Duo CPU @ 1,866 GHz, 2GB RAM, Pypy 5.10.1
rounds per test: 10000
=====================================
>>> parsing (IP + ICMP)
orC = 86064 p/s
orP = 208346 p/s
>>> creating/direct assigning (IP only header)
orC = 41623 p/s
orP = 59370 p/s
>>> bin() without change (IP)
orC = 170356 p/s
orP = 292133 p/s
>>> output with change/checksum recalculation (IP)
orC = 10104 p/s
orP = 23851 p/s
>>> basic/first layer parsing (Ethernet + IP + TCP + HTTP)
orC = 62748 p/s
orP = 241047 p/s
>>> changing Triggerlist element value (Ethernet + IP + TCP + HTTP)
orC = 101552 p/s
orP = 201994 p/s
>>> changing Triggerlist/text based proto (Ethernet + IP + TCP + HTTP)
orC = 37249 p/s
orP = 272972 p/s
>>> direct assigning and concatination (Ethernet + IP + TCP + HTTP)
orC = 7428 p/s
orP = 14315 p/s
>>> full packet parsing (Ethernet + IP + TCP + HTTP)
orC = 6886 p/s
orP = 17040 p/s
性能测试结果：pypacker vs. dpkt vs. scapy
Comparing pypacker, dpkt and scapy performance (parsing Ethernet + IP + TCP + HTTP)
orC = Intel Core2 Duo CPU @ 1,866 GHz, 2GB RAM, CPython v3.6
orC2 = Intel Core2 Duo CPU @ 1,866 GHz, 2GB RAM, CPython v2.7
rounds per test: 10000
=====================================
>>> testing pypacker parsing speed
orC = 17938 p/s
>>> testing dpkt parsing speed
orC = 12431 p/s
>>> testing scapy parsing speed
orC2 = 726 p/s
Q : 我应该从哪里开始学习使用 Pypacker ？
答：如果你通过阅读示例就已经了解了 Scapy 应该没问题。另外，文档中包含 pypacker 的一般介绍，其中显示了 pypacker 的用法和概念。
问：pypacker 有多快？
答：参见上面的结果。要获得机器上的详细结果，请执行测试。
问：有文档吗？
答：Pypacker 是基于 dpkt 的代码，而 dpkt 没有任何官方且内部代码文档很少。这使得理解内部行为变得棘手。毕竟 Pypacker 的代码文档已经得到了很大的扩展。文档可以在这些目录和文件中找到：
协议本身（参见 LayerXYZ）通常没有太多文档，因为这些文档是由各自的 RFC/官方标准记录的。
问：支持哪些协议？
答：目前最低支持的协议有：Ethernet、Radiotap、IEEE80211、ARP、DNS、STP、PPP、OSPF、VRRP、DTP、IP、ICMP、PIM、IGMP、IPX、TCP、UDP、SCTP、HTTP、NTP、RTP、 DHCP、RIP、SIP、Telnet、HSRP、直径、SSL、TPKT、Pmap、半径、BGP
问：如何添加协议？
答：简短的回答：扩展 Packet 类并添加类变量__hdr__来定义标头字段。长答案：有关非常完整的示例，请参阅examples/examples_new_protocol.py。
问：我如何为这个项目做出贡献？
答：请使用 Github 错误跟踪器来获取错误/功能请求。在提交新错误之前，请阅读错误跟踪器以了解已知的错误。补丁可以通过拉取请求发送。
问：Pypacker 在哪个许可证下发布？
答：这是 GPLv2 许可证（有关详细信息，请参阅许可证文件）。
问：有计划支持[协议xyz]吗？
答：Pypacker 中添加了对特定协议的支持，这是人们贡献该支持的结果 - 没有正式计划在特定的未来版本中添加对特定协议的支持。
问：使用 Windows 3.11/XP/7/8/mobile 等的 Pypacker 存在问题 xyz。您能解决这个问题吗？
答：基本功能应该适用于任何操作系统。可选的可能会带来麻烦（例如拦截器），并且不会对此提供支持。为什么？因为质量很重要，我不会为劣质系统提供支持。在选择操作系统之前要三思而后行并应对后果；不要因为你的决定而责怪别人。或者：给我金钱补偿，我看看我能做什么(;
# This will lazy parse only needed layers behind the scenes
if ether.src == "...":
...
elif ip.src == "...":
...
elif tcp.sport == "...":
...
pkt = Ethernet() + IP() + TCP()
# This parses ALL layers
packet_print = "%s" % pkt
packet_found = pkt[Telnet]
# Alternative: Use multi-value index-notation. This will stop parsing at any non-matching layer:
packet_found = pkt[Ethernet,IP,TCP,Telnet]
pkt = ip.IP(src_s="1.2.3.4", dst_s="1.2.3.5") + tcp.TCP()
# Disable checksum calculation (and any other update) for IP and TCP (only THIS packet instance)
pkt.sum_au_active = False
pkt.tcp.sum_au_active = False
bts = pkt.bin(update_auto_fields=False)
sysctl -w net.core.rmem_max=12582912
sysctl -w net.core.rmem_default=12582912
sysctl -w net.core.wmem_max=12582912
sysctl -w net.core.wmem_default=12582912
sysctl -w net.core.optmem_max=2048000
sysctl -w net.core.netdev_max_backlog=5000
sysctl -w net.unix.max_dgram_qlen=1000
sysctl -w net.ipv4.tcp_rmem="10240 87380 12582912"
sysctl -w net.ipv4.tcp_wmem="10240 87380 12582912"
sysctl -w net.ipv4.tcp_mem="21228 87380 12582912"
sysctl -w net.ipv4.udp_mem="21228 87380 12582912"
sysctl -w net.ipv4.tcp_window_scaling=1
sysctl -w net.ipv4.tcp_timestamps=1
sysctl -w net.ipv4.tcp_sack=1
