Re: [squid-users] Capturing HTTPS traffic

From: James R. Leu <jleu_at_mindspring.com>
Date: Sun, 5 Feb 2012 13:37:58 -0600

I do not have sslbump working yet, but as I understand it the packets
on the wire are always encrypted. The only place the information exists
in a decrypted form is in squids memory. Just think of squid as a bridge
between two SSL streams.

On Sun, Feb 05, 2012 at 02:12:44PM -0500, PS wrote:
> I tried using ssldump and tshark and I can't seem to get this working. I am using squid's private key to try to decrypt the traffic.
>
> The connection goes from the client (192.168.2.2) to squid server (192.168.2.1) on port 3128. If I understand correctly, the client establishes a connection with squid on port 3128 and then squid establishes a connection with https://www.gmail.com on port 443.
>
> Shouldn't I be able to decrypt the connection between the client and the squid server in order to see the traffic that is being sent to gmail?
>
> On Feb 3, 2012, at 2:08 PM, "Alfonso Alejandro Reyes Jimenez" <aareyes_at_scitum.com.mx> wrote:
>
> > Sorry. SSLDUMP is like tcpdump but for ssl, it Works on layer 3 and has nothing to do with squid, that what we use.
> >
> > Regards.
> >
> >
> >
> > -----Mensaje original-----
> > De: PS [mailto:packetstack_at_gmail.com]
> > Enviado el: viernes, 03 de febrero de 2012 12:56 p.m.
> > Para: Alfonso Alejandro Reyes Jimenez
> > CC: squid-users_at_squid-cache.org
> > Asunto: Re: [squid-users] Capturing HTTPS traffic
> >
> > Could you please be a little more specific? Is there something else called ssldump that I am supposed to use?
> >
> > This is what my config looks like. I am currently using ssl_bump.
> >
> >
> > acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
> > acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
> > acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
> > acl localnet src fc00::/7 # RFC 4193 local private network range
> > acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines
> > acl SSL_ports port 443
> > acl Safe_ports port 80 # http
> > acl Safe_ports port 21 # ftp
> > acl Safe_ports port 443 # https
> > acl Safe_ports port 70 # gopher
> > acl Safe_ports port 210 # wais
> > acl Safe_ports port 1025-65535 # unregistered ports
> > acl Safe_ports port 280 # http-mgmt
> > acl Safe_ports port 488 # gss-http
> > acl Safe_ports port 591 # filemaker
> > acl Safe_ports port 777 # multiling http
> > acl CONNECT method CONNECT
> > http_access allow localhost manager
> > http_access deny manager
> > http_access deny !Safe_ports
> > http_access deny CONNECT !SSL_ports
> > http_access allow localnet
> > http_access allow localhost
> > http_access deny all
> > http_port 3128 ssl-bump generate-host-certificates=on dynamic_cert_mem_cache_size=4MB cert=/usr/local/squid/ssl_cert/squid.pem
> > always_direct allow all
> > ssl_bump allow all
> > sslproxy_cert_error allow all
> > sslproxy_flags DONT_VERIFY_PEER
> > coredump_dir /usr/local/squid/var/cache/squid
> > refresh_pattern ^ftp: 1440 20% 10080
> > refresh_pattern ^gopher: 1440 0% 1440
> > refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
> > refresh_pattern . 0 20% 4320
> > logformat squid %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %un %Sh/%<A %mt access_log /usr/local/squid/var/logs/access.log squid
> >
> > Thanks for the quick response!
> >
> > On Feb 3, 2012, at 1:20 PM, Alfonso Alejandro Reyes Jimenez wrote:
> >
> >> Hi.
> >>
> >> If you have the certifícate information you may use ssldump to decode the information. I hope this helps.
> >>
> >>
> >> Regards.
> >>
> >> -----Mensaje original-----
> >> De: PS [mailto:packetstack_at_gmail.com] Enviado el: viernes, 03 de
> >> febrero de 2012 12:11 p.m.
> >> Para: squid-users_at_squid-cache.org
> >> Asunto: [squid-users] Capturing HTTPS traffic
> >>
> >> Hello,
> >>
> >> I am currently running the following version of Squid:
> >>
> >> Squid Cache: Version 3.2.0.14-20120202-r11500 configure options: '--enable-ssl' '--enable-ssl-crtd'
> >>
> >> I configured it so that certs are generated on the fly and I am able to get to HTTPS websites without getting a certificate warning.
> >>
> >> I want to do a packet capture of all HTTPS traffic while in cleartext. I would think that it can be done on the Squid box. Is that possible?
> >>
> >> If I use tcpdump on the Squid box, I only see the encrypted traffic. Do I have to recompile Squid with another configuration option to be able to do what I want to do?
> >>
> >> Thanks
> >

-- 
James R. Leu
jleu_at_mindspring.com

Received on Sun Feb 05 2012 - 19:38:05 MST

This archive was generated by hypermail 2.2.0 : Mon Feb 06 2012 - 12:00:01 MST