options to set-log-level silent for failed or error connections
Hi everyone, wanted to ask for help regarding error logs and log silencing. I played around with silencing some monitoring hosts with the "set-log-level silent" option. During testing I noticed that silencing the logs worked, but only on "successfull" connections. As soon as the connect is regarded as some sort of failure, the silencing does not work and the log gets written. For example when you are recevinging TCP checks on a TLS listener, all of them are regarded as failures and hence don't get silenced. Cant find a solution in the descriptions provided via the cbonte.github.io docs configuration.html. Is there a reason error/failed connections are regarded differently when it comes to "set-log-level" ? Does it have to do with the connect not beeing in the stage of "tcp-request content", but "tcp-request connection" when the failure occurs? Do I have other options of working around this? Please find my configuration and information to reproduce the steps at the end. Thanks and best Regards, Micha OS: # grep PRETTY /etc/os-release PRETTY_NAME="Ubuntu 20.04.5 LTS" I tested with these 2 versions of haproxy: # haproxy -version HAProxy version 2.5.9-1ppa1~focal 2022/09/24 - https://haproxy.org/ Status: stable branch - will stop receiving fixes around Q1 2023. Known bugs: http://www.haproxy.org/bugs/bugs-2.5.9.html Running on: Linux 5.4.0-131-generic #147-Ubuntu SMP Fri Oct 14 17:07:22 UTC 2022 x86_64 # haproxy -version HAProxy version 2.6.6-1ppa1~focal 2022/09/22 - https://haproxy.org/ Status: long-term supported branch - will stop receiving fixes around Q2 2027. Known bugs: http://www.haproxy.org/bugs/bugs-2.6.6.html Running on: Linux 5.4.0-131-generic #147-Ubuntu SMP Fri Oct 14 17:07:22 UTC 2022 x86_64 Here is the configuration i used (should work out of the box, once the snakeoil certs are symlinked). I used the openssl/nc commands at the end for testing (via localhost). # cat haproxy.cfg.set-log-level global log stdout format raw local0 info pidfile /var/run/haproxytest.pid crt-base /etc/ssl/private defaults timeout connect 3s timeout client 3s timeout server 3s frontend fend # ln -s /etc/ssl/certs/ssl-cert-snakeoil.pem /etc/ssl/private/ssl-cert-snakeoil.pem # ln -s /etc/ssl/private/ssl-cert-snakeoil.key /etc/ssl/private/ssl-cert-snakeoil.pem.key bind :1234 ssl crt ssl-cert-snakeoil.pem mode tcp log global no option dontlognull tcp-request content set-log-level silent if { src 127.0.0.1/32 } log-format "[%t] %ci:%cp > %fi:%fp %ft %b %s %Tw/%Tc/%Tt rtx:%U/%B %ts" #option log-separate-errors error-log-format 'ERROR: [%t] %ci:%cp > %fi:%fp %ft %b %s %Tw/%Tc/%Tt rtx:%U/%B %ts' default_backend bend backend bend server local-nc-k-l8000 localhost:8000 # echo | openssl s_client -connect localhost:1234 -quiet # echo | nc -vw1 localhost 1234
Re: payload inspection using req.payload
Hey Mathias, wow, brilliant! Made my day, really! - I was about getting frustrated during troubleshooting :) That was exactly what I needed. Thanks a bunch! Failed to find something like that, because I was not exactly knowing what to search for. > As a side note: In case you want to match the payload in a binary (non-HTTP) protocol, > make sure you convert the payload to hex first, see section 7.1.3 in the > newest configuration docs, here's the excerpt: Yes, thats right. Luckily I already had some experience how to handle that type of stuff from previous scripting jobs. I wrote a bin2hex function for the LUA script I am testing. Not sure, maybe in terms of performance(?) it makes more sense to leave that to haproxy "payload(),hex" and just evaluate the converted result in my script. Will have a look into that. So far I got the impression tshooting and testing patterns is more "obvious" and debug-able when implemented in my own LUA script. Felt a bit "blind" on tracking decision making when testing a haproxy ACLs equivalent (maybe just my first impression) Used "set-var" + "if acl" and printed that via log-format, not sure if there is a better way when testing ACLs? Thanks again, BR Micha On 12.02.2020 12:09, Mathias Weiersmüller (cyberheads GmbH) wrote: Hi Micha, My problem is that the "req.payload(0,10)" fetch, which I am using for that purpose, does not seem to reliably have access to the payload at all times. The problem is not the fetch per se, it is the timing of the evaluation of the rule: tcp-request content rules are evaluated very early - there's a high probability the payload buffer is empty at this moment. if you add a condition to check if there is already any content present, it will always match (checked using your config, thanks!): example: tcp-request content set-var(txn.rawPayload) req.payload(0,2),hex if { req_len gt 0 } As a side note: In case you want to match the payload in a binary (non-HTTP) protocol, make sure you convert the payload to hex first, see section 7.1.3 in the newest configuration docs, here's the excerpt: Do not use string matches for binary fetches which might contain null bytes (0x00), as the comparison stops at the occurrence of the first null byte. Instead, convert the binary fetch to a hex string with the hex converter first. Example: # matches if the string is present in the binary sample acl tag_found req.payload(0,0),hex -m sub 3C7461673E Best regards Mathias
payload inspection using req.payload
Hi everyone, writing to get some help on a setup I am building with haproxy. Part of the setup is a content inspection of the tcp payload (binary stream), for which the load balancing will be done. Testing with content inspection based on simple ACL pattern matches but also tried evaluating the payload in LUA scripts. Where the latter is my personal preference. In the end the incoming requests should be accepted/rejected, based on the payload evaluation result. My target is to process multiple hundreds of simultaneous requests at peak times, which *ALL* should undergo a payload inspection for the initial request. Scenario will also terminate TLS later on, but this should make no difference for the inspection (at least to my understanding) My problem is that the "req.payload(0,10)" fetch, which I am using for that purpose, does not seem to reliably have access to the payload at all times. So far I was not able to find out, what the cause of that could be. There were several mitigation hints on that problem, but somehow I am failing to get it to work. For troubleshooting I got down to a very simplistic setup, which just accesses the payload and prints it to the logfile. I am using apache benchmark "ab" to generate ingress traffic for larger batches. An apache server acts as a test backend. Please not this is just for testing purposes. The final protocol is *NOT* http. I think this is negligible atm(?) as the part I am focussing on is actual inboud/eval stuff, before the backend is contacted. So out of a 100 requests sent with "ab" about 10-50% of the requests are failing to display payload content. I also noticed, that localhost generated ab requests have a much higher chance of failing to print the payload. Have the strong feeling that the payload is trying to be accessed before its fully available to haproxy - even if its just a few bytes (testing with 2-8) Kind of lost here at the moment and I would really be grateful for any suggestions and help on that one. Is there a reasonable way to reliably "wait" for incoming requests w/o delaying the requests too much in the end? Best Regards Micha Below you can find the setup I came up with: # VERSIONS $ grep VERSION= /etc/os-release VERSION="18.04.4 LTS (Bionic Beaver)" $ grep 2.1 /etc/apt/sources.list.d/vbernat-ubuntu-haproxy-2_0-bionic.list deb http://ppa.launchpad.net/vbernat/haproxy-2.1/ubuntu bionic main $ haproxy -vv HA-Proxy version 2.1.2-1ppa1~bionic 2019/12/21 - https://haproxy.org/ Status: stable branch - will stop receiving fixes around Q1 2021. Known bugs: http://www.haproxy.org/bugs/bugs-2.1.2.html Build options : TARGET = linux-glibc CPU = generic CC = gcc CFLAGS = -O2 -g -O2 -fdebug-prefix-map=/build/haproxy-HuTwKZ/haproxy-2.1.2=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -fno-strict-aliasing -Wdeclaration-after-statement -fwrapv -Wno-unused-label -Wno-sign-compare -Wno-unused-parameter -Wno-old-style-declaration -Wno-ignored-qualifiers -Wno-clobbered -Wno-missing-field-initializers -Wno-implicit-fallthrough -Wno-stringop-overflow -Wtype-limits -Wshift-negative-value -Wshift-overflow=2 -Wduplicated-cond -Wnull-dereference OPTIONS = USE_PCRE2=1 USE_PCRE2_JIT=1 USE_REGPARM=1 USE_OPENSSL=1 USE_LUA=1 USE_ZLIB=1 USE_SYSTEMD=1 Feature list : +EPOLL -KQUEUE -MY_EPOLL -MY_SPLICE +NETFILTER -PCRE -PCRE_JIT +PCRE2 +PCRE2_JIT +POLL -PRIVATE_CACHE +THREAD -PTHREAD_PSHARED +REGPARM -STATIC_PCRE -STATIC_PCRE2 +TPROXY +LINUX_TPROXY +LINUX_SPLICE +LIBCRYPT +CRYPT_H -VSYSCALL +GETADDRINFO +OPENSSL +LUA +FUTEX +ACCEPT4 -MY_ACCEPT4 +ZLIB -SLZ +CPU_AFFINITY +TFO +NS +DL +RT -DEVICEATLAS -51DEGREES -WURFL +SYSTEMD -OBSOLETE_LINKER +PRCTL +THREAD_DUMP -EVPORTS Default settings : bufsize = 16384, maxrewrite = 1024, maxpollevents = 200 Built with multi-threading support (MAX_THREADS=64, default=2). Built with OpenSSL version : OpenSSL 1.1.1 11 Sep 2018 Running on OpenSSL version : OpenSSL 1.1.1 11 Sep 2018 OpenSSL library supports TLS extensions : yes OpenSSL library supports SNI : yes OpenSSL library supports : TLSv1.0 TLSv1.1 TLSv1.2 TLSv1.3 Built with Lua version : Lua 5.3.3 Built with network namespace support. Built with transparent proxy support using: IP_TRANSPARENT IPV6_TRANSPARENT IP_FREEBIND Built with PCRE2 version : 10.31 2018-02-12 PCRE2 library supports JIT : yes Encrypted password support via crypt(3): yes Built with zlib version : 1.2.11 Running on zlib version : 1.2.11 Compression algorithms supported : identity("identity"), deflate("deflate"), raw-deflate("deflate"), gzip("gzip") Built with the Prometheus exporter as a service Available polling systems : epoll : pref=300, test result OK poll : pref=200, test result OK select : pref=150, test result OK Total: 3 (3 usable), will use epoll. Available multiplexer protocols : (protocols marked as cannot be specified using 'proto' keyword) h2 : mode=HTTP side=FE|BE mux=H2