On 07/12/2018 01:17 PM, --Ahmad-- wrote: > if i have pc# 1 and that pc open facebook . > > then i have other pc # 2 and that other pc open facebook . > > > now as we know facebook is https . > > so is the key/ cert that used on pc # 1 is same as cert in pc # 2 to decrypt the fb encrypted traffic ? Certificates themselves are not used (directly) to decrypt traffic AFAIK, but yes, both PCs will see the same server certificate (ignoring CDNs and other complications). > now in the presence of squid . > > if i used tcp connect method , will it be different than above ? If you are not bumping the connection, then both PCs will see the same real Facebook certificate as if those PCs did not use a proxy. If you are bumping the connection, then both PCs will see the same fake certificate generated by Squid. > say i used 200 proxies in same squid machine and i used to access FB from the same pc same browser . > > will facebook see my cert/key i used to decrypt its traffic ? If you are asking whether Facebook will know anything about the fake certificate generated by Squid for clients, then the answer is "no, unless Facebook runs some special client code to deliver (Squid) certificate back to Facebook". In general, the origin server assumes that the client is talking to it directly. Clients may pin or otherwise restrict certificates that they trust, but after the connection is successfully established, the server may assume that it is talking to the client directly. A paranoid server may deliver special code to double check that assumption, but there are other, more standard methods to prevent bumping such as certificate pinning and certificate transparency cervices. > is the key/cert of FB to decrypt the https content is same on all browsers on all computers ? If you are asking whether the generated certificates are going to be the same for all clients, then the answer is "yes, provided all those 200 Squids use the same configuration (including the CA certificate) and receive the same real certificate from Facebook". Squid's certificate generation algorithm generates the same certificate given the same configuration and the same origin server certificate. HTH, Alex. _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users