SMTP
是否可以使用Scapy执行最简单的会话?我试图读取tcpdump
使用Scapy
和发送数据包捕获的内容,但没有运气......
这就是我所拥有的
#!/usr/bin/python
from scapy.all import *
from scapy.layers.inet import IP, TCP
source_ip = '1.2.3.4'
source_port = 5100
source_isn = 1000
dest_ip = '1.2.3.5'
dest_port = 25
ip=IP(src=source_ip, dst=dest_ip)
SYN=TCP(sport=source_port, dport=dest_port, flags="S", seq=source_isn)
SYNACK=sr1(ip/SYN)
source_isn = SYN.seq + 1
source_ack = SYNACK.seq + 1
CK=TCP(ack=source_ack, sport=source_port, dport=dest_port, flags="A",seq=source_isn)
handshakedone=sr1(ip/ACK)
DTA=TCP(ack=handshakedone.seq+len(handshakedone.load), seq=source_isn, sport=source_port,dport=dest_port,flags="PA")
sr(ip/DTA/Raw(load='mail from: test@gmail.com\r\n'))
send(ip/DTA/Raw(load='rcpto to: me@gmail.com\r\n'))
source_isn = ACK.seq + len(mfrom)
.....
RST=TCP(ack=SYNACK.seq + 1, seq=source_isn, sport=source_port, dport=dest_port, flags="RA")
send(ip/RST)
握手是成功的,但在会话期间应该是什么ACK
和价值观?SEQ
我该如何计算它们?