Allwyn
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The Tale of A Spoofed EMAIL In A Poem

Humans have for long used myths, poems and such to express our deepest fears, feelings and awe with the world.

And along the same spirit, I found this poem below on stackexchange. This explains the deepest feelings of a lonely mail server.

The question is why is it so easy to SPAM emails. Me sending you one which looks like it’s from barack.obama@whitehouse.gov or from your bank or mom, or whoever.

I have a copy here below, but even I’d prefer you go read it where I found it.

Context: an e-mail server, alone in a bay, somewhere in Moscow. The server just sits there idly, with an expression of expectancy.

Server:
Ah, long are the days of my servitude,
That shall be spent in ever solitude,
‘Ere comes hailing from the outer rings
The swift bearer of external tidings.

A connection is opened.

Server:
An incoming client ! Perchance a mail
To my guardianship shall be entrusted
That I may convey as the fairest steed
And to the recipient bring the full tale.

220 mailserver.kremlin.ru ESMTP Postfix (Ubuntu)

Welcome to my realm, net wanderer,
Learn that I am a mighty mail server.
How will you in this day be addressed
Shall the need rise, for your name to be guessed ?

Client:
HELO whitehouse.gov

Hail to thee, keeper of the networking,
Know that I am spawned from the pale building.

Server:
250 mailserver.kremlin.ru

The incoming IP address resolves through the DNS to “nastyhackerz.cn”.

Noble envoy, I am yours to command,
Even though your voice comes from the hot plains
Of the land beyond the Asian mountains,
I will comply to your flimsiest demand.

Client:
MAIL FROM: barack.obama@whitehouse.gov
RCPT TO: vladimir.putin@kremlin.ru
Subject: biggest bomb

I challenge you to a contest of the biggest nuclear missile,
you pathetic dummy ! First Oussama, then the Commies !
.

Here is my message, for you to send,
And faithfully transmit on the ether;
Mind the addresses, and name of sender
That shall be displayed at the other end.

Server:
250 Ok

So it was written, so it shall be done.
The message is sent, and to Russia gone.

The server sends the email as is, adding only a “Received:” header to mark the name which the client gave in its first command. Then Third World War begins. The End.

Commentary: there’s no security whatsoever in email. All the sender and receiver names are indicative and there is no reliable way to detect spoofing (otherwise there would me much fewer spams).

Allwyn
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Printers, NAS and other devices on different LANs on the same Fortigate

I started this thread on the network engineering Q&A site.

I have now found the answer to it as well. It’s a weird situation.

I had opened a ticket with Fortinet’s TAC for the printer query which I have posted and he just enabled NAT on the WI-FI interface on which the printer is connected and the issue was resolved.

After this with another client of mine, I faced the same situation this time with an NAS storage device. And voila I had to enable NAT on the interface to which the NAS box was connected to.

For some reason any such device like printers, NAS etc. don’t seem to respond to communication from another subnet on the same fortigate and NAT solves the problem.

The same setup works fine if it was a PC in place of the printer.

UPDATE – 5th Feb 2016

One of those light bulb moments! The printers and NAS devices probably were NOT configured with a default gateway and so they never had a default route to send packets to with a destination IP address other than a directly connected one. They never had a route for any other network other than the one they were directly plugged into!

Hence when NAT was enabled, the printers could reply to the fortigate’s interface IP which would NAT the source IP of the other subnet.

The PCs on the other hand configured with a little more caution had the default gateway and hence would send all packets with unknown IP address to their default gateway.

Allwyn
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Blocking HTTPs websites without SSL inspection on Fortigate

One of my clients wanted to block facebook but without using SSL inspection as he didn’t want to install the cert to 100s of his staff computers.
I explained that with that there would be no other way to get it done. This coming from all of Fortinet’s own documentation obviously. 
Then to convince the client I opened a fortinet ticket and got the same response that this can’t be done without the ssl inspection and certificate installation.
Now this guy hired some other service provider and those guys simply blocked social media signatures in app control and applied it to the policy and IT HAS WORKED.
It doesn’t say “fortiguard blocked” but just keeps the loading icon spinning and facebook doesn’t load at all.
The whole situation turned pretty embarrassing for us.

 

The Confusion

 

Fortinet must spend some time on cleaning up its archives of posts and videos with outdated info i guess.

 

Here in this and this video its displayed how https is blocked seamlessly by just using the SSL inspection inspect all ports method without any importing any certificate. And nothing about SSL certificate warnings is touched upon which almost always pops up when using HTTPs inspection. The Fortinet TAC’s response was also appeared what I can call very non-committal, TAC simply told “you must install the certificate if you get any errors”, really now I doubt there’s ever a situation when you don’t get cert errors which ssl inspection on. 
Allwyn
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Automatic backup fortigate firewalls with batch file

Firewall configuration backups can save hours of reconfiguration when one of your firewalls goes nuked due to any reason whatsoever.

While fortigates have a backup button, that gets boring and repetitive soon when you reach 10 fortigates to backup daily.

I put up this following backup utility using windows batch programming and of course credit goes to all those blogs and posts I referred. This uses secure copy which must be enabled on the device.

Here is the batch code along with the .txt file you can download. Once you download the .txt just rename it to .bat for it to work.

@echo off
for /f ” eol=# tokens=1-4 delims=,”  %%i in (fgts.txt) do CALL :oneaddr %%i %%j %%k %%l
echo end
goto :EOF
:oneaddr
cd c:Program FilesPuTTY
pscp -pw %3 %2@%1:sys_config C:backup%4-%DATE%-%TIME::=%.conf

Download The Bat File

What I have highlighted in red is another .txt file which is to be fed as input to the .bat code above and both should be in the same directory.

The folder where the config files will be downloaded should already exist. And the file will be downloaded with the .conf extension there.

Also highlighted is the location where your putty is installed should match with the one in the batch file (and yes putty can be installed).

What this input file contains is the IP address, admin name, admin password and device name.
The format must be: (Keep adding more on each line.)

 x.x.x.x,username,password,devicename
y.y.y.y,username2,password2,devicename2
z.z.z.z,username3,password3,devicename3

The interface of the IP you’re providing should have SSH enabled.

Once you have everything ready just put both the bat and input txt file in a folder.

Now the last thing you need is to enable admin-scp on your foritgate device. The CLI way to do it is:

config system global
    set admin-scp enable
end

And now you just have to doubleclick the .bat file and you will see all your fortigates being backed up one by one with a name-date-time stamp.

I can hear your worries about storing passwords to firewalls in txt. You can minimize the risk by configuring read_only admin accounts on the firewalls or else just take of the that input .txt file.
Allwyn
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Checking to confirm fortigate port forwarding by debugging

fortigate destination NAT debug CLI

A few days back one of my clients had doubts whether the port he required was forwarded correctly on the FGT.

I assured him it was and asked him to check with his IT teams whether the port was accepting traffic on the server locally, I guess many people get confused that for port forwarding to work correctly the port in question should also be open on the server or the application. These people were using Tomcat7.

Since his other IT team wasn’t convinced I decided to just send him a log of the debug from FGT.

After little quick googling I got to this post on the fortinet forum and found the debug code below on that very post.

Here’s the debug command to check this.

diag debug enable
diag debug flow filter dport 80(the destination port which you have configured in VIP)
diag debug flow filter saddr
diag debug flow  show console enable
diag debug flow trace start 100(this I guess is the number of packets or hits..will have to look this up)

<Your public IP address> I say public because when you would be sending traffic to this FGT to generate the debug logs, your incoming traffic will have the source IP of your wan which is aka your public IP. I’m sure someone out there is getting no logs at all because he’s gone all ipconfig and added his 192.168… in there which is the internal LAN network IP aka your private address.

To clear the debug filters use
diag debug reset
diad debug disable
diag debug flow filter clear
You should clear the filters every time before running the debug again.

Once your debug commands are in, just go through your browser and access the FGT’s IP as
http://x.x.x.x:yy where yy is the forwarded port, for eg: 8080, 8888, 3389 and so on. I was working with the simple port 80 so all i needed to do was http://x.x.x.x as http uses port 80.

The debug generated is as follows:

BSH # id=36871 trace_id=525 msg=”vd-root received a packet(proto=6, z.z.z.z:52957->x.x.x.x:80) from wan2.”
id=36871 trace_id=525 msg=”allocate a new session-0036f1c2″
id=36871 trace_id=525 msg=”find SNAT: IP-172.168.1.2(from IPPOOL), port-80″
id=36871 trace_id=525 msg=”VIP-172.168.1.2:80, outdev-wan2″
id=36871 trace_id=525 msg=”DNAT x.x.x.x:80->172.168.1.2:80″
id=36871 trace_id=525 msg=”find a route: gw-172.168.1.2 via internal”
id=36871 trace_id=525 msg=”Allowed by Policy-2:” 

Again x.x.x.x is the target FGT’s public IP and z.z.z.z is my public IP from where I sent the traffic to generate the logs.

I swear this is the easiest to understand debug output ever. Everything is just right there.
Allwyn
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Unblocking Google earth on Fortigate and probably other firewalls

google earth fortigate

Google earth servers keep changing and you could be connecting to anyone which serves you the best.

 

At a client’s google earth would work fine but the street view would feature which should be as clear as standing on the road in some city would look all scrambled and jumbled up.

 

Their support forum here has a list of URLs to be allowed:
and some IPs:

74.125.227.1
74.125.227.3
74.125.227.7
74.125.227.17
67.215.65.132  
74.125.79.120 

Instead of allowing each of them, you just have to check their Fortiguard rating and confirm which webfilter category they fall into. Most them are in the following.
Reference
Search engines
Content servers

I was stuck with the last one—content server. None of the URLs above actually fall into it and the street view was still jumbled up.

Then I decided to get the big guns out—Fortinet Debugger. I could sense the errors already shaking in their boots.
diag debug enable
diagnose debug urlfilter src-addr <Your LAN PC IP here>
diag debug flow show console enable
diag debug flow trace start 100 (the no. of lines you want to be traced)

 

then stop and reset the debugging:
diag debug reset
diag debug disable

You will see the destination URL in the log and then again check the Fortiguard category or just allow the URL.

Allwyn
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Blocking facebook, youtube over HTTPS on Fortigate

A few months back I was in hell over blocking Youtube for one of my clients.

I blocked it on webfilter  with certificate SSL inspection turned on and later even applied application control to it, in the end — the page opened straight away like nothing exists in between.

Later the good old fortinet TAC put me out of misery and showed my how YouTube slid past by the SSL certificate inspection as knife through butter because some of google’s websites now use a very different form of SSL — QUIC.

Look in the lock icon to the left of your address bar to see this:

Says right there the connection uses QUIC.

Fortinet has a nice little doc here on how to block it.

I’d just recommend you make this a part of your base configuration and always disable QUIC. This interferes with not only for webfilter and app control but say you want to do some email filtering, blocking gmail attachments or even stop google drive the traffic will just slip by with QUIC enabled.

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