pypacker
1.0.0
這是 Pypacker：Python 最快、最簡單的資料包操作庫。它允許您透過定義所有標頭資料的各個方面來手動建立資料包，透過解析原始資料包位元組來剖析資料包，在不同層上發送/接收資料包以及攔截資料包。
建立指定特定值的資料包或採用預設值：
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' )從檔案（pcap/tcpdump 格式）讀取資料包，分析並將其寫回：
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 ()攔截（和修改）資料包，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 ()發送和接收資料包：
# 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：
請參閱範例/和測試/test_pypacker.py。
測試執行如下：
效能測試結果：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
效能測試結果：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 : 我該從哪裡開始學習使用 Pypacker ？
答：如果你透過閱讀範例就已經了解 Scapy 應該沒問題了。另外，文件中包含 pypacker 的一般介紹，其中顯示了 pypacker 的用法和概念。
Q ：pypacker 有多快？
答：參見上面的結果。要獲得機器上的詳細結果，請執行測試。
Q ：有文檔嗎？
答：Pypacker 是基於 dpkt 的程式碼，而 dpkt 沒有任何官方且內部程式碼文件很少。這使得理解內在行為變得棘手。畢竟 Pypacker 的程式碼文件已經得到了很大的擴展。文件可以在這些目錄和文件中找到：
協議本身（參見 LayerXYZ）通常沒有太多文檔，因為這些文檔是由各自的 RFC/官方標準記錄的。
Q ：支援哪些協定？
答：目前最低支援的協定有：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、直徑、SSL、TPKT、Pmap、半徑、BGP
Q ：如何新增協議？
答：簡短的回答：擴展 Packet 類別並新增類別變數__hdr__來定義標頭欄位。長答案：有關非常完整的範例，請參閱examples/examples_new_protocol.py。
Q ：我如何為這個專案做出貢獻？
答：請使用 Github 錯誤追蹤器來取得錯誤/功能請求。在提交新錯誤之前，請閱讀錯誤追蹤器以了解已知的錯誤。補丁可以透過拉取請求發送。
Q ：Pypacker 在哪個許可證下發布？
答：這是 GPLv2 許可證（有關詳細信息，請參閱許可證文件）。
Q ：有計劃支援[協議xyz]嗎？
答：Pypacker 中添加了對特定協議的支持，這是人們貢獻該支持的結果 - 沒有正式計劃在特定的未來版本中添加對特定協議的支持。
Q ：使用 Windows 3.11/XP/7/8/mobile 等的 Pypacker 有問題 xyz。
答：基本功能應該適用於任何作業系統。可選的可能會帶來麻煩（例如攔截器），並且不會對此提供支援。為什麼？因為品質很重要，我不會為劣質系統提供支援。在選擇作業系統之前要三思而後行並應對後果；不要因為你的決定而責怪別人。或：給我金錢補償，我看看我能做什麼(;
# 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
