\u7b97\u6cd5\u5982\u4e0b<\/div>\n

#Created by vessial<\/div>\n

<\/p>\n

def p2p_udp_encrypt(pkt):<\/p>\n

header=random.randint(0,0xffff)<\/p>\n

t=((header&0x1fff)+0x4000)<<0x10<\/p>\n

t+=random.randint(0,0xffff)<\/p>\n

body=struct.pack(‘I’,t)<\/p>\n

sec2=random.randint(0,0xff)<\/p>\n

body+=struct.pack(‘B’,sec2)<\/p>\n

length=(sec2&0x03)+9<\/p>\n

pos=length<\/p>\n

for i in range(length-5):<\/p>\n

x=random.randint(0,0xff)<\/p>\n

body+=struct.pack(‘B’,x)<\/p>\n

l=pos*7<\/p>\n

t=struct.unpack(‘B’,body[pos-3])[0]<\/p>\n

t*=0x0d<\/p>\n

t&=0xff<\/p>\n

k=l^t<\/p>\n

header=body[:pos-2]+struct.pack(‘B’,k)<\/p>\n

t=struct.unpack(‘B’,header[-1])[0]<\/p>\n

t*=0x0d<\/p>\n

t&=0xff<\/p>\n

k=(l+7)^t<\/p>\n

header=header+struct.pack(‘B’,k)<\/p>\n

out=”<\/p>\n

j=0<\/p>\n

t=array.array(‘B’,header)<\/p>\n

buf=array.array(‘B’,pkt)<\/p>\n

body_len=len(pkt)<\/p>\n

for i in range(body_len):<\/p>\n

j+=1<\/p>\n

if j==pos:<\/p>\n

j=0<\/p>\n

x=t[j]+0x5b<\/p>\n

x&=0xff<\/p>\n

x^=t[j-1]<\/p>\n

t[j-1]=x<\/p>\n

buf[i]=(buf[i]+x)&0xff<\/p>\n

out=header+buf.tostring()<\/p>\n

#print “out buf len is %d”%len(out)<\/p>\n

#print hexdump(out)<\/p>\n

#print hexdump(p2p_udp_decrypt(out))<\/p>\n

return out<\/p>\n

def p2p_udp_decrypt(pkt):<\/p>\n

if len(pkt)<=8:<\/p>\n

return False<\/p>\n

header=struct.unpack(‘<I’,pkt[:4])[0]<\/p>\n

header>>=0x1d<\/p>\n

if header>3:<\/p>\n

return False<\/p>\n

elif header ==1:<\/p>\n

pass<\/p>\n

elif header ==2:<\/p>\n

byte5=struct.unpack(‘B’,pkt[4])[0]<\/p>\n

byte5&=0x80000003<\/p>\n

byte5+=9<\/p>\n

if byte5>len(pkt):<\/p>\n

return False<\/p>\n

pos=byte5<\/p>\n

head_check=array.array(‘B’,pkt[:pos])<\/p>\n

t=struct.unpack(‘B’,pkt[pos-2])[0]<\/p>\n

mid=pos*7<\/p>\n

p=7*pos+7<\/p>\n

t*=0x0d<\/p>\n

t&=0xff<\/p>\n

p^=t<\/p>\n

s=struct.unpack(‘B’,pkt[pos-1])[0]<\/p>\n

if p != s:<\/p>\n

return False<\/p>\n

t=struct.unpack(‘B’,pkt[pos-3])[0]<\/p>\n

t*=0x0d<\/p>\n

t&=0xff<\/p>\n

t^=mid<\/p>\n

if t !=struct.unpack(‘B’,pkt[pos-2])[0]:<\/p>\n

return False<\/p>\n

j=0<\/p>\n

body=array.array(‘B’,pkt[pos:])<\/p>\n

body_len=len(pkt)-pos<\/p>\n

for i in range(body_len):<\/p>\n

j+=1<\/p>\n

if j==pos:<\/p>\n

j=0<\/p>\n

x=head_check[j]+0x5b<\/p>\n

x&=0xff<\/p>\n

x^=head_check[j-1]<\/p>\n

head_check[j-1]=x<\/p>\n

body[i]=(body[i]-x)&0xff<\/p>\n

x=body.tostring()<\/p>\n

#print hexdump(x)<\/p>\n

return x<\/p>\n

elif header ==3:<\/p>\n

pass<\/p>\n

return False<\/p>\n","protected":false},"excerpt":{"rendered":"

\u6765\u6e90\uff1ahttp:\/\/hi.baidu.com\/vessial\/blog\/item …<\/p>\n