[Bro] Bro behind a TLS reverse proxy

Brandon Sterne brandon.sterne at gmail.com
Tue Apr 10 10:57:08 PDT 2018


Hi Philip,

I'm not sure what differs between your environment and mine. On my
VirtualBox C7 box I see the bad packet (pcaps attached):
[vagrant at localhost ~]$ sha1sum pcaps/lo-port80.pcap
6f44be24c1491ddf4285c6e4c585fc1d8b307439  pcaps/lo-port80.pcap
[vagrant at localhost ~]$ tshark -t ud -r pcaps/lo-port80.pcap | head -n6
  1 2018-04-09 23:16:28          ::1 -> ::1          TCP 94 58156 > http
[SYN] Seq=0 Win=43690 Len=0 MSS=65476 SACK_PERM=1 TSval=8358348 TSecr=0
WS=64
  2 2018-04-09 23:16:28          ::1 -> ::1          TCP 74 http > 58156
[RST, ACK] Seq=1 Ack=1 Win=0 Len=0
  3 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 74 43060 > http
[SYN] Seq=0 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=8358349 TSecr=0
WS=64
  4 1971-02-20 11:53:55    127.0.0.1 -> 127.0.0.1    TCP 74 http > 43060
[SYN, ACK] Seq=0 Ack=1 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=8358349
TSecr=8358349 WS=64
  5 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
[ACK] Seq=1 Ack=1 Win=43712 Len=0 TSval=8358349 TSecr=8358349
  6 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    HTTP 139 GET /
HTTP/1.1

I ran another test today on C7 bare metal, and this time I saw a problem
with the first SYN-ACK packet, but this time the timestamp was far in the
future:
[brandon.sterne at s-mxq61403r3 pcaps]$ sha1sum lo-port-80-bm.pcap
20dbe8f5e67668ef1f6e37724910470cd4e47d74  lo-port-80-bm.pcap
[brandon.sterne at s-mxq61403r3 pcaps]$ tshark -t ud -r lo-port-80-bm.pcap |
head -n6
  1 2018-04-10 17:13:22          ::1 -> ::1          TCP 94 53636 > http
[SYN] Seq=0 Win=43690 Len=0 MSS=65476 SACK_PERM=1 TSval=3967522213 TSecr=0
WS=128
  2 2018-04-10 17:13:22          ::1 -> ::1          TCP 74 http > 53636
[RST, ACK] Seq=1 Ack=1 Win=0 Len=0
  3 2018-04-10 17:13:22    127.0.0.1 -> 127.0.0.1    TCP 74 42944 > http
[SYN] Seq=0 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=3967522213 TSecr=0
WS=128
  4 2061-07-14 21:16:16    127.0.0.1 -> 127.0.0.1    TCP 74 http > 42944
[SYN, ACK] Seq=0 Ack=1 Win=43690 Len=0 MSS=65495 SACK_PERM=1
TSval=3967522213 TSecr=3967522213 WS=128
  5 2018-04-10 17:13:22    127.0.0.1 -> 127.0.0.1    TCP 66 42944 > http
[ACK] Seq=1 Ack=1 Win=43776 Len=0 TSval=3967522213 TSecr=3967522213
  6 2018-04-10 17:13:22    127.0.0.1 -> 127.0.0.1    HTTP 139 GET /
HTTP/1.1

Do others see anything like this? I appreciate any help you can offer in
reducing the testcase and identifying the offending software.

Best,
Brandon


On Tue, Apr 10, 2018 at 8:57 AM, Philip Romero <promero at cenic.org> wrote:

> FYI - I was able to run the test commands on a VirtualBox VM and the
> results show that the date appears correct.
>
> $ tshark -t ud -r lo-port-80.pcap
>   1 2018-04-10 15:36:12          ::1 -> ::1          TCP 94 37816 > http
> [SYN] Seq=0 Win=43690 Len=0 MSS=65476 SACK_PERM=1 TSval=4294908231 TSecr=0
> WS=128
>   2 2018-04-10 15:36:12          ::1 -> ::1          TCP 74 http > 37816
> [RST, ACK] Seq=1 Ack=1 Win=0 Len=0
>   3 2018-04-10 15:36:12    127.0.0.1 -> 127.0.0.1    TCP 74 32966 > http
> [SYN] Seq=0 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=4294908231 TSecr=0
> WS=128
>   4 2018-04-10 15:36:12    127.0.0.1 -> 127.0.0.1    TCP 54 http > 32966
> [RST, ACK] Seq=1 Ack=1 Win=0 Len=0
> $
>
> Philip
>
> On 4/10/18 8:21 AM, bro-request at bro.org wrote:
>
> Send Bro mailing list submissions to
> 	bro at bro.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
> 	http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/bro
> or, via email, send a message with subject or body 'help' to
> 	bro-request at bro.org
>
> You can reach the person managing the list at
> 	bro-owner at bro.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Bro digest..."
>
>
> Today's Topics:
>
>    1. building a bro plugin (erik clark)
>    2. Re: Bro behind a TLS reverse proxy (Philip Romero)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Tue, 10 Apr 2018 10:48:30 -0400
> From: erik clark <philosnef at gmail.com> <philosnef at gmail.com>
> Subject: [Bro] building a bro plugin
> To: Bro-IDS <bro at bro.org> <bro at bro.org>
> Message-ID:
> 	<CAK6atxqrZjAOXpj9QgtZV8WDjGUw8nFcSTLQSMMJgvS8i0Dj=A at mail.gmail.com> <CAK6atxqrZjAOXpj9QgtZV8WDjGUw8nFcSTLQSMMJgvS8i0Dj=A at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> I have tried everything I can think of to get this to compile:
> https://github.com/supriyask/Bro
>
> Can someone explain to me what needs to be provided either in the
> CMakeLists.txt or at the cmake cli to build this? Thanks. The readme has no
> information whatsoever.
> -------------- next part --------------
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> ------------------------------
>
> Message: 2
> Date: Tue, 10 Apr 2018 08:21:00 -0700
> From: Philip Romero <promero at cenic.org> <promero at cenic.org>
> Subject: Re: [Bro] Bro behind a TLS reverse proxy
> To: bro at bro.org
> Message-ID: <92728a56-e307-7513-5131-93a5ec749b94 at cenic.org> <92728a56-e307-7513-5131-93a5ec749b94 at cenic.org>
> Content-Type: text/plain; charset="utf-8"
>
> I don't know if this messes up your test, but I didn't have tshark on
> the physical box I'm running. Below is the output showing the date via
> tcpdump options. It looks correct.?
>
> $ tcpdump -ttttnnr lo-port-80.pcap
> reading from file lo-port-80.pcap, link-type EN10MB (Ethernet)
> 2018-04-10 08:13:20.209770 IP6 ::1.49258 > ::1.80: Flags [S], seq
> 485780875, win 43690, options [mss 65476,sackOK,TS val 1090368614 ecr
> 0,nop,wscale 7], length 0
> 2018-04-10 08:13:20.209809 IP6 ::1.80 > ::1.49258: Flags [R.], seq 0,
> ack 485780876, win 0, length 0
> 2018-04-10 08:13:20.210015 IP 127.0.0.1.43960 > 127.0.0.1.80: Flags [S],
> seq 859064153, win 43690, options [mss 65495,sackOK,TS val 1090368615
> ecr 0,nop,wscale 7], length 0
> 2018-04-10 08:13:20.210046 IP 127.0.0.1.80 > 127.0.0.1.43960: Flags
> [R.], seq 0, ack 859064154, win 0, length 0
> $
>
> Philip
>
>
> On 4/9/18 9:21 PM, bro-request at bro.org wrote:
>
> Send Bro mailing list submissions to
> 	bro at bro.org
>
> To subscribe or unsubscribe via the World Wide Web, visit
> 	http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/bro
> or, via email, send a message with subject or body 'help' to
> 	bro-request at bro.org
>
> You can reach the person managing the list at
> 	bro-owner at bro.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Bro digest..."
>
>
> Today's Topics:
>
>    1. Re: Bro behind a TLS reverse proxy (Brandon Sterne)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Mon, 9 Apr 2018 21:21:35 -0700
> From: Brandon Sterne <brandon.sterne at gmail.com> <brandon.sterne at gmail.com>
> Subject: Re: [Bro] Bro behind a TLS reverse proxy
> To: Micha? Purzy?ski <michalpurzynski1 at gmail.com> <michalpurzynski1 at gmail.com>
> Cc: Bro-IDS <bro at bro.org> <bro at bro.org>
> Message-ID:
> 	<CADXmT7CqnNFykCP0dQXmOz+B7wfhsEDrrT25Ct+62UjzA=bW0g at mail.gmail.com> <CADXmT7CqnNFykCP0dQXmOz+B7wfhsEDrrT25Ct+62UjzA=bW0g at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> I can confirm this also happens on a C7 OpenStack VM:
> [brandon.sterne at sterne-server ~]$ tshark -t ud -r pcaps/lo-port-80.pcap
>   1 2018-04-10 03:35:40    127.0.0.1 -> 127.0.0.1    TCP 74 51546 > http
> [SYN] Seq=0 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=595251 TSecr=0
> WS=128
>   2 2018-04-10 03:35:40    127.0.0.1 -> 127.0.0.1    TCP 54 http > 51546
> [RST, ACK] Seq=1 Ack=1 Win=0 Len=0
>   3 2018-04-10 03:35:52    127.0.0.1 -> 127.0.0.1    TCP 74 51548 > http
> [SYN] Seq=0 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=607469 TSecr=0
> WS=128
>   4 1970-01-31 04:44:20    127.0.0.1 -> 127.0.0.1    TCP 74 http > 51548
> [SYN, ACK] Seq=0 Ack=1 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=607469
> TSecr=607469 WS=128
>   5 2018-04-10 03:35:52    127.0.0.1 -> 127.0.0.1    TCP 66 51548 > http
> [ACK] Seq=1 Ack=1 Win=43776 Len=0 TSval=607469 TSecr=607469
>   6 2018-04-10 03:35:52    127.0.0.1 -> 127.0.0.1    HTTP 139 GET /
> HTTP/1.1
>   <snip>
>
> I can't locate a C7 bare metal server right at the moment but will try to
> test that tomorrow. If someone happens to have a C7 bare metal box and
> would be willing to test, here is the sequence of commands to run:
> [shell1]$ sudo tcpdump -s 0 -i lo -w lo-port-80.pcap "port 80"
> [shell2]$ curl localhost
> [shell1]$ ^C
> [shell1]$ tshark -t ud -r lo-port-80.pcap
>
>
> On Mon, Apr 9, 2018 at 4:25 PM, Brandon Sterne <brandon.sterne at gmail.com> <brandon.sterne at gmail.com>
> wrote:
>
>
> This is very interesting. It is totally reproducible with CentOS 7 VMs,
> but I confirmed the testcase works as expected with an Ubuntu Server VM. On
> a freshly provisioned C7 VM, I see "That 70s Packet" when I capture from
> the loopback interface, but not when I capture from the external interface:
>
> ```[vagrant at localhost pcaps]$ tshark -t ud -r lo-port80.pcap
>   1 2018-04-09 23:16:28          ::1 -> ::1          TCP 94 58156 > http
> [SYN] Seq=0 Win=43690 Len=0 MSS=65476 SACK_PERM=1 TSval=8358348 TSecr=0
> WS=64
>   2 2018-04-09 23:16:28          ::1 -> ::1          TCP 74 http > 58156
> [RST, ACK] Seq=1 Ack=1 Win=0 Len=0
>   3 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 74 43060 > http
> [SYN] Seq=0 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=8358349 TSecr=0
> WS=64
>   4 1971-02-20 11:53:55    127.0.0.1 -> 127.0.0.1    TCP 74 http > 43060
> [SYN, ACK] Seq=0 Ack=1 Win=43690 Len=0 MSS=65495 SACK_PERM=1 TSval=8358349
> TSecr=8358349 WS=64
>   5 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=1 Ack=1 Win=43712 Len=0 TSval=8358349 TSecr=8358349
>   6 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    HTTP 139 GET /
> HTTP/1.1
>   7 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 http > 43060
> [ACK] Seq=1 Ack=74 Win=43712 Len=0 TSval=8358349 TSecr=8358349
>   8 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 83 [TCP segment
> of a reassembled PDU]
>   9 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=74 Ack=18 Win=43712 Len=0 TSval=8358351 TSecr=8358351
>  10 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 103 [TCP segment
> of a reassembled PDU]
>  11 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=74 Ack=55 Win=43712 Len=0 TSval=8358351 TSecr=8358351
>  12 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 103 [TCP segment
> of a reassembled PDU]
>  13 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=74 Ack=92 Win=43712 Len=0 TSval=8358351 TSecr=8358351
>  14 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 106 [TCP segment
> of a reassembled PDU]
>  15 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=74 Ack=132 Win=43712 Len=0 TSval=8358351 TSecr=8358351
>  16 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 87 [TCP segment
> of a reassembled PDU]
>  17 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=74 Ack=153 Win=43712 Len=0 TSval=8358351 TSecr=8358351
>  18 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 68 [TCP segment
> of a reassembled PDU]
>  19 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=74 Ack=155 Win=43712 Len=0 TSval=8358351 TSecr=8358351
>  20 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    HTTP 512 HTTP/1.0 200
> OK  (text/html)
>  21 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [ACK] Seq=74 Ack=601 Win=44800 Len=0 TSval=8358351 TSecr=8358351
>  22 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 http > 43060
> [FIN, ACK] Seq=601 Ack=74 Win=43712 Len=0 TSval=8358351 TSecr=8358351
>  23 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 43060 > http
> [FIN, ACK] Seq=74 Ack=602 Win=44800 Len=0 TSval=8358351 TSecr=8358351
>  24 2018-04-09 23:16:28    127.0.0.1 -> 127.0.0.1    TCP 66 http > 43060
> [ACK] Seq=602 Ack=75 Win=43712 Len=0 TSval=8358351 TSecr=8358351
> [vagrant at localhost pcaps]$ tshark -t ud -r eth1-port80.pcap
>   1 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 78 53640 > http
> [SYN, ECN, CWR] Seq=0 Win=65535 Len=0 MSS=1460 WS=32 TSval=240784579
> TSecr=0 SACK_PERM=1
>   2 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 74 http > 53640
> [SYN, ACK, ECN] Seq=0 Ack=1 Win=28960 Len=0 MSS=1460 SACK_PERM=1
> TSval=556841 TSecr=240784579 WS=64
>   3 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [ACK] Seq=1 Ack=1 Win=131744 Len=0 TSval=240784579 TSecr=556841
>   4 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 HTTP 415 GET /
> HTTP/1.1
>   5 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 66 http > 53640
> [ACK] Seq=1 Ack=350 Win=30080 Len=0 TSval=556842 TSecr=240784579
>   6 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 83 [TCP segment
> of a reassembled PDU]
>   7 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [ACK] Seq=350 Ack=18 Win=131744 Len=0 TSval=240784581 TSecr=556843
>   8 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 103 [TCP segment
> of a reassembled PDU]
>   9 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [ACK] Seq=350 Ack=55 Win=131712 Len=0 TSval=240784581 TSecr=556844
>  10 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 103 [TCP segment
> of a reassembled PDU]
>  11 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [ACK] Seq=350 Ack=92 Win=131648 Len=0 TSval=240784581 TSecr=556844
>  12 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 106 [TCP segment
> of a reassembled PDU]
>  13 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [ACK] Seq=350 Ack=132 Win=131616 Len=0 TSval=240784581 TSecr=556844
>  14 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 87 [TCP segment
> of a reassembled PDU]
>  15 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 HTTP 466 HTTP/1.0
> 200 OK  (text/html)
>  16 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [ACK] Seq=350 Ack=153 Win=131616 Len=0 TSval=240784581 TSecr=556844
>  17 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [ACK] Seq=350 Ack=554 Win=131200 Len=0 TSval=240784581 TSecr=556844
>  18 2018-04-09 21:06:26 192.168.43.1 -> 192.168.43.10 TCP 66 53640 > http
> [FIN, ACK] Seq=350 Ack=554 Win=131200 Len=0 TSval=240784581 TSecr=556844
>  19 2018-04-09 21:06:26 192.168.43.10 -> 192.168.43.1 TCP 66 http > 53640
> [ACK] Seq=554 Ack=351 Win=30080 Len=0 TSval=556844 TSecr=240784581
> ```
>
> It's a good question, Micha?. Whose bug is this? I'm happy to go chase it
> down with the right audience if we can answer this question. Thanks for
> taking the time to look.
>
> Cheers,
> Brandon
>
>
> On Mon, Apr 9, 2018 at 3:34 PM, Micha? Purzy?ski <michalpurzynski1 at gmail.com> wrote:
>
>
> To help with the investigation, I also observed a similar behavior on
> some CentOS 7.x hosts, when capturing traffic into a pcap on a live system
> would result in some packets being saved with the 70's timestamp.
>
> The question remain - is that a kernel bug, a network card bug, a driver
> bug?
>
> On Mon, Apr 9, 2018 at 1:33 PM, Seth Hall <seth at corelight.com> <seth at corelight.com> wrote:
>
>
> I don't know how it happened, but the timestamp for the SYN/ACK packet
> in your pcap is March 22, 1970. Bro uses the timestamps from packets to
> track it's notion of time moving forward and with Bro's internal clock
> being shoved around by nearly 50 years twice in the span of three packets
> will throw it off pretty badly (lots of timeouts take place). ;)
>
> Any clue why the timestamp on that packet would be like that? It's just
> the one packet in your pcap that is messed up too.
>
> .Seth
>
> On 9 Apr 2018, at 11:56, Brandon Sterne wrote:
>
> Hi Justin,
>
> Thank you for the reply. I don't think it is the MTU that is preventing
> the sensor from decoding the traffic correctly. I ran the same test case
> with snaplen=65535 and still received only the connection_established
> event:
>
> [vagrant at localhost security-gateway]$ sudo bro -C -i lo snaplen=65535
> rules/bro/detect-http-request.bro
> <params>, line 1: listening on lo, capture length 65535 bytes
>
> Connection: , [id=[orig_h=127.0.0.1, orig_p=34902/tcp, resp_h=127.0.0.1,
> resp_p=80/tcp], orig=[size=0, state=4, num_pkts=1, num_bytes_ip=60,
> flow_label=0], resp=[size=0, state=4, num_pkts=0, num_bytes_ip=0,
> flow_label=0], start_time=1523289116.669146, duration=-1516793840.109909,
> service={
>
> }, history=Sh, uid=Ch6Tqk39qjgHi6li88, tunnel=<uninitialized>,
> dpd=<uninitialized>, conn=<uninitialized>, extract_orig=F, extract_resp=F,
> thresholds=<uninitialized>, dhcp=<uninitialized>, dnp3=<uninitialized>,
> dns=<uninitialized>, dns_state=<uninitialized>, ftp=<uninitialized>,
> ftp_data_reuse=F, ssl=<uninitialized>, http=<uninitialized>,
> http_state=<uninitialized>, irc=<uninitialized>, krb=<uninitialized>,
> modbus=<uninitialized>, mysql=<uninitialized>, radius=<uninitialized>,
> rdp=<uninitialized>, sip=<uninitialized>, sip_state=<uninitialized>,
> snmp=<uninitialized>, smtp=<uninitialized>, smtp_state=<uninitialized>,
> socks=<uninitialized>, ssh=<uninitialized>, syslog=<uninitialized>]
>
> I'm attaching the script I'm using and the pcap for the same request,
> taken with:
> sudo tcpdump -i lo -s 0 -w port8080.pcap
>
> Thanks,
> Brandon
>
>
> On Wed, Apr 4, 2018 at 3:01 PM, Azoff, Justin S <jazoff at illinois.edu> <jazoff at illinois.edu>
> wrote:
>
>
> On Apr 2, 2018, at 12:04 AM, Brandon Sterne <brandon.sterne at gmail.com> <brandon.sterne at gmail.com>
>
> wrote:
>
> Hello,
>
> I am attempting to get Bro working sitting behind a reverse proxy
>
> (nginx), which is receiving connections, terminating TLS, and forwarding
> cleartext HTTP to a local app server (Tomcat). I have a really simple test
> case that demonstrates the problem I'm running into, which is that Bro HTTP
> events are only detected when requests are sent plaintext (without TLS).
> Here is the test case I'm using:
>
> The output you have included is not enough to tell what is wrong.
> Minimally, full conn.log entries are required to figure out what bro is
> seeing.  Even better would be a full pcap of the traffic that bro is not
> properly decoding.
>
> To just guess, i'd say your problem is that the MTU on lo is 65536 and
> bro is not configured by default to handle that.  Throwing a
>
> redef Pcap::snaplen = 65536
>
> in your script may get things working.
>
>
> ?
> Justin Azoff
>
>
>
> _______________________________________________
> Bro mailing listbro at bro-ids.orghttp://mailman.ICSI.Berkeley.EDU/mailman/listinfo/bro
>
> --
> Seth Hall * Corelight, Inc * www.corelight.com
>
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> Bro mailing listbro at bro-ids.orghttp://mailman.ICSI.Berkeley.EDU/mailman/listinfo/bro
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>
> End of Bro Digest, Vol 144, Issue 12
> ************************************
>
>
> --
> Philip Romero, CISSP, CISA
> Sr. Information Security Analyst
> CENICpromero at cenic.org
> Phone: (714) 220-3430
> Mobile: (562) 237-9290
>
>
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