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    SSLBUMP without MITM

    Scheduled Pinned Locked Moved Cache/Proxy
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    • D
      doktornotor Banned
      last edited by

      OK, so I guess there are no changes really required for the SquidGuard + SSL usecase. Thanks for feedback.

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      • jimpJ
        jimp Rebel Alliance Developer Netgate
        last edited by

        To summarize, this does work with transparent interception without installing a CA on clients, but I can only get it to see the domain name, not the full URL as some in the thread have stated.

        • Squid General tab, Show Advanced Options, Custom ACLs (before auth)
        acl bump_step1 at_step SslBump1
        ssl_bump peek bump_step1 all
        ssl_bump splice all
        sslproxy_cert_error deny all
        
        • ACLs tab, whitelist:```
          .*
        
        When squidGuard blocks it kills the connection, it doesn't redirect or do anything nice.
        
        And naturally this doesn't let you see the body so no chance for AV or similar to check the contents.

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        • D
          doktornotor Banned
          last edited by

          @jimp: As I understand the previous post, there's really no need to put anything into Custom ACLs; the code is equivalent to what we have in the package already when you whitelist everything (.*) - there's

          ssl_bump splice whitelist
          ssl_bump bump all

          (and the second line won't have anything to match left when you've whitelisted everything)

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          • jimpJ
            jimp Rebel Alliance Developer Netgate
            last edited by

            Ah, so all you need is the whitelist ".*" and the rest happens automatically? Cool. That does seem to work.

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            • D
              doktornotor Banned
              last edited by

              Yeah, it's basically "supertransparent", as in - no certificates forged/no need to install certs on clients. (And yeah, obviously it's limited in sense that you just get enough info about the connection for SquidGuard to do its job, but nothing else, i.e., no content filtering/AV/etc.)

              Perhaps could use some hints in the GUI…

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              • jimpJ
                jimp Rebel Alliance Developer Netgate
                last edited by

                Would be nice to kick that in somehow when CA = "None" when using SSL Interception, or at least allow CA = None to be set in that case. It doesn't seem like that should be necessary since it isn't going to be using the CA when acting in that role. I haven't tried it though, maybe squid is dumb and still needs it set.

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                • D
                  doktornotor Banned
                  last edited by

                  Yeah, afraid that's a no go, the certs are really required - plus, the ACL (whitelist) can be anything there and be changed at any time,  or have lines prepended/appended, really no way for Squid to figure out it's not going to need to fake any certs.

                  (But you could generate a temporary one for the CA in the background on each config resync; would need additional logic/code though in squid.inc. If you want something like this, I'd prefer having a separate checkbox for this, with some JS logic that'd gray out/disable unneeded MITM stuff in the GUI, and use a different ACL than the current whitelist for that, basically just use the built-in "all" one - like ssl_bump splice all)

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                  • S
                    shonjir
                    last edited by

                    I'm running a variation of this config in transparent mode with squidguard and shallalist quite successfully.

                    I'm not sure why exactly, but this configuration improves over basic step 1 peek and splice all by allowing logging of the server certificate (instead of just IP address), domain blocking of SSL sites via squidguard list, and provides an alternate splice operation for certain sites that for some reason cannot connect after the certificate name is captured.

                    # peek at client TLS-request to get SNI
                    # peek at server cert (for logging)
                    # splice earlySplice at step 3 only
                    acl earlySplice ssl::server_name "*.crashplan.com"
                    ssl_bump peek step1
                    ssl_bump peek step2 earlySplice
                    ssl_bump splice step3 earlySplice
                    ssl_bump splice all
                    sslproxy_cert_error deny all
                    
                    
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                    • D
                      doktornotor Banned
                      last edited by

                      Well yes, that will no doubt improve splice since you get whole lot more information available at steps 2/3, as explained here:
                      https://github.com/pfsense/FreeBSD-ports/blob/devel/www/pfSense-pkg-squid/files/usr/local/pkg/squid.inc#L1539

                      The above makes bumping impossible, however.

                      It's not possible to do zillion variants in the GUI. Use Advanced Options, Custom ACLs (before auth).

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                      • S
                        shonjir
                        last edited by

                        The above makes bumping impossible, however.

                        This is understood.  For my use case, I don't need full blown MiTM - logging the site name and simple domain blocking are sufficient.

                        Right now I'm using custom ACLs for this.  It's a hack (because it supersedes the auto-generated ssl_bump directives that follow), but it works.

                        It would be nice if it were available as a simple toggle in the config or if the various ssl config options were exposed for customization under 'advanced', but it works reasonably well as-is.

                        Thank you for your work making this tool available!

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                        • D
                          doktornotor Banned
                          last edited by

                          I'll see if something reasonable can be added for

                          • splice everything without bump (i.e., splice all)
                          • custom splice ACLs/settings (some advanced textarea burried somewhere, if you break it, your problem)

                          without overcomplicating the GUI and confusing everyone.

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                          • D
                            doktornotor Banned
                            last edited by

                            OK, how's this?

                            https://github.com/pfsense/FreeBSD-ports/pull/269

                            ssl_mitm_mode_01.png
                            ssl_mitm_mode_01.png_thumb
                            ssl_mitm_mode_02.png
                            ssl_mitm_mode_02.png_thumb

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                            • jimpJ
                              jimp Rebel Alliance Developer Netgate
                              last edited by

                              Looks great, we're getting that PR merged in right now, thanks!

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                              • D
                                doktornotor Banned
                                last edited by

                                Thanks for testing/feedback. Any volunteers to fixrewrite SquidGuard now? (No, I cannot do it. Tried many times, unable to work with that code for more than a couple of minutes.)

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                                • F
                                  fabiomello
                                  last edited by

                                  e2guardian its more active…
                                  if you want to replace squidGuard with e2guardian i could do this!

                                  what you think?

                                  https://github.com/e2guardian/e2guardian

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                                  • D
                                    doktornotor Banned
                                    last edited by

                                    @fabiomello:

                                    e2guardian its more active…
                                    if you want to replace squidGuard with e2guardian i could do this!

                                    what you think?

                                    https://github.com/e2guardian/e2guardian

                                    Hmmm… good luck.

                                    • https://forum.pfsense.org/index.php?topic=87526.0
                                    • https://github.com/pfsense/pfsense-packages/pull/866
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                                    • jimpJ
                                      jimp Rebel Alliance Developer Netgate
                                      last edited by

                                      From the history there it looks like it had a similar problem to squidGuard. Whatever happens, it needs a ground-up rewrite with up-to-date style and practices all-around.

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                                      Do not Chat/PM for help!

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                                      • D
                                        doktornotor Banned
                                        last edited by

                                        Yeah. The XMLs in the linked e2guardian PR would be a good starting point to get a grip of potential feature set. The PHP code there still needs major work, though it must have been a  lot better than SquidGuard, considering I've been able to somehow finish the code style at least. :P

                                        The PHP-generated package XML is a major can of worms there.

                                        Plus note, that PR was for 2.2.x, lots of changes meanwhile.

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                                        • S
                                          susamlicubuk
                                          last edited by

                                          Good job. Congratulations.
                                          Tag_none / 200 for all https and ip address is not good to appear in logs
                                          Do you have a solution for this problem?
                                          A manual DNS problem can sometimes cause the page not found error
                                          We continue to test this issue

                                          Tag_None.JPG
                                          Tag_None.JPG_thumb

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                                          • D
                                            doktornotor Banned
                                            last edited by

                                            And the issue is exactly what? TAG_NONE/XXX means spliced connection. It works. Really nothing to fix here. This is a TCP tunnel, Squid won't handle any HTTP there.

                                            http://squid-web-proxy-cache.1019090.n4.nabble.com/TAG-NONE-xxxx-td4672150.html

                                            If you have issues with some sites, you'll need to use some custom ACL and custom config for that at the moment, I'm afraid.

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