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@LeeBrotherston
Created February 21, 2016 05:38
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Detect TLS Client Hello in many things using a BPF
Match TLS Client Hello packets with a BPF:
IPv4 + TCP: (tcp[tcp[12]/16*4]=22 and (tcp[tcp[12]/16*4+5]=1) and (tcp[tcp[12]/16*4+9]=3) and (tcp[tcp[12]/16*4+1]=3))
IPv6 + TCP: (ip6[(ip6[52]/16*4)+40]=22 and (ip6[(ip6[52]/16*4+5)+40]=1) and (ip6[(ip6[52]/16*4+9)+40]=3) and (ip6[(ip6[52]/16*4+1)+40]=3))
Teredo
(IPv6 + TCP over IPv4 + UDP): ((udp[14] = 6 and udp[16] = 32 and udp[17] = 1) and ((udp[(udp[60]/16*4)+48]=22) and (udp[(udp[60]/16*4)+53]=1) and (udp[(udp[60]/16*4)+57]=3) and (udp[(udp[60]/16*4)+49]=3)))
6in4 (IPv6 + TCP over IPv4): (proto 41 and ip[26] = 6 and ip[(ip[72]/16*4)+60]=22 and (ip[(ip[72]/16*4+5)+60]=1) and (ip[(ip[72]/16*4+9)+60]=3) and (ip[(ip[72]/16*4+1)+60]=3)
Complete: (tcp[tcp[12]/16*4]=22 and (tcp[tcp[12]/16*4+5]=1) and (tcp[tcp[12]/16*4+9]=3) and (tcp[tcp[12]/16*4+1]=3)) or (ip6[(ip6[52]/16*4)+40]=22 and (ip6[(ip6[52]/16*4+5)+40]=1) and (ip6[(ip6[52]/16*4+9)+40]=3) and (ip6[(ip6[52]/16*4+1)+40]=3)) or ((udp[14] = 6 and udp[16] = 32 and udp[17] = 1) and ((udp[(udp[60]/16*4)+48]=22) and (udp[(udp[60]/16*4)+53]=1) and (udp[(udp[60]/16*4)+57]=3) and (udp[(udp[60]/16*4)+49]=3))) or (proto 41 and ip[26] = 6 and ip[(ip[72]/16*4)+60]=22 and (ip[(ip[72]/16*4+5)+60]=1) and (ip[(ip[72]/16*4+9)+60]=3) and (ip[(ip[72]/16*4+1)+60]=3))
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