Featured Nginx How to use Brotli compression for Centmin Mod Nginx web servers

yeah seems we aren't seeing brotli served from Cloudflare's servers at all

 

yeah that page shows Brotli only for HTTP/2 pushed assets while at normal cloudflare site Cloudflare - The Web Performance & Security Company | Cloudflare it's showing gzip only so maybe only for HTTP/2 pushed assets?

 

FYI, for folks playing with the pre-compress brotli.sh tool, I have made a few big improvement updates to it outlined at centminmod.com/brotlistatic

 

in favour of which ? brotli.sh precompresses gz and br versions. So would make some sense as Centmin Mod Nginx will uses gzip_static and brotli_static meaning if you pre-gzip static file, Centmin Mod Nginx will serve that pre-gzipped static file to Cloudflare and they'd cache it to serve from their edge. Just that Cloudflare seems to ignore the pre-brotli compressed static files I guess. Pre-gzipped is still faster than on the fly gzip whether it be on backend origin or Cloudflare's edge servers.

 

you used brotli.sh to precompress gz and br versions or just use brotli on the fly compression ?

 

From what i understand Cloudflare takes your backend server (Centmin Mod Nginx) requests as uncompressed as you disabled on the fly gzip compression. Then Cloudflare serves that request as either gzip or non-gzip depending on the client's browser request header for Accept Encoding. In your specific case Cloudflare now compresses that uncompressed data sent from your backend on their Cloudflare Nginx server side.

i.e. request header would tell Cloudflare server or Centmin Mod Nginx (in non Cloudflare configs) that browser supports gzip, deflate, sdch and br compression

Code (Text):

accept-encoding: gzip, deflate, sdch, br

Why it would be faster for @SFLC with brotli.sh pre-gzipped or pre-brotli compressed assets is that both Centmin Mod Nginx and I assume Cloudflare Nginx servers support gzip_static directive so if a pre-gzipped asset is detected it is served bypassing the time it takes to compress on the fly at either Cloudflare Nginx server or Centmin Mod Nginx server side.

Also brotli.sh pre-gzipped and pre-brotli compressed assets will use higher compression levels on average than on the fly Nginx configured gzip and brotli compression so assets are compressed to smaller size = faster page loads. Though Cloudflare Nginx from what I read even uses gzip compression level 9 for on the fly as they have alot more cpu resources available and offset by caching at server and browser cache level. Whereas, Centmin Mod Nginx defaults to gzip compression level 5 or 6 depending on branch for on the fly compression so to balance cpu load to compression time. For brotli.sh pre-gzipped and pre-brotli compressed assets, compression levels for pre-gzipped files uses pigz level 11 which is Zopfli based compression which results in smaller compressed files than gzip max level 9 if more than 1 cpu thread is detected. If 1 cpu thread only detected falls back from pigz to gzip level 6 compression for pre-gzipped files.

Folks can use webpagetest.org to test their Brotli vs Gzip enabled configurations

edit: added some example numbers for compressed file sizes vs original file for brotli and gzip (via pigz)

Code (Text):

ls -lah /usr/local/nginx/html/brotlitests/
total 364K
drwxr-sr-x  2 root  nginx 4.0K Mar  5 13:10 .
drwxr-sr-x. 4 nginx nginx 4.0K Mar  5 12:44 ..
-rw-r--r--  1 root  nginx 119K Jul 25  2016 bootstrap.min.css
-rw-r--r--  1 root  nginx  16K Jul 25  2016 bootstrap.min.css.br
-rw-r--r--  1 root  nginx  20K Jul 25  2016 bootstrap.min.css-bro4.br
-rw-r--r--  1 root  nginx  18K Jul 25  2016 bootstrap.min.css-bro5.br
-rw-r--r--  1 root  nginx  18K Jul 25  2016 bootstrap.min.css-bro6.br
-rw-r--r--  1 root  nginx  18K Jul 25  2016 bootstrap.min.css-pigz11.gz
-rw-r--r--  1 root  nginx  20K Jul 25  2016 bootstrap.min.css-pigz6.gz
-rw-r--r--  1 root  nginx  37K Jul 25  2016 bootstrap.min.js
-rw-r--r--  1 root  nginx 8.6K Jul 25  2016 bootstrap.min.js.br
-rw-r--r--  1 root  nginx  11K Jul 25  2016 bootstrap.min.js-bro4.br
-rw-r--r--  1 root  nginx 9.3K Jul 25  2016 bootstrap.min.js-bro5.br
-rw-r--r--  1 root  nginx 9.3K Jul 25  2016 bootstrap.min.js-bro6.br
-rw-r--r--  1 root  nginx 9.3K Jul 25  2016 bootstrap.min.js-pigz11.gz
-rw-r--r--  1 root  nginx  11K Jul 25  2016 bootstrap.min.js-pigz6.gz

 

yup Alex's second response is pretty much what i said here. So for you probably be worth re-enabling gzip compression on Centmin Mod Nginx

 

Might want to ask Cloudflare as they would be better informed as to current state of BREACH attack and mitigation - afterall the whole internet and security based WAF firewalls online still enable gzip compression.

FYI, Centmin Mod 123.09beta01 optionally supports that nginx-length-hiding-filter-module for nginx via variable you can set in persistent config /etc/centminmod/custom_config.inc prior to nginx recompile via centmin.sh menu option 4

Code (Text):

NGINX_LENGTHHIDE='n'         # https://github.com/nulab/nginx-length-hiding-filter-module

Unfortunately, i haven't be able to get it to work i.e. can't see the random string inserted into my site's html pages. Edit: apparently that was fixed for incompatibility with HTTP/2 nginx 1.11.3 ? · Issue #4 · nulab/nginx-length-hiding-filter-module · GitHub so worth retrying/retesting Edit: tried and still doesn't work for me heh

Might want to start a separate thread for that NGINX_LENGTHHIDE option or ask at https://community.centminmod.com/th...ilter-module-in-123-09beta01.8360/#post-34764

example of it enabled with NGINX_LENGTHHIDE='y' and nginx recompiled via centmin.sh menu option 4

 

still not working for me heh https://community.centminmod.com/posts/45877/

 

Note, CRIME and BREACH only apply to HTTPS based requests not non-HTTPS. More explained on BREACH here Anatomy of a cryptographic oracle – understanding (and mitigating) the BREACH attack

Lets test against cloudflare.com web site via dev ssllabs and testssl tools and compare to Centmin Mod HTTP/2 HTTPS defaults - results should both are migitated for common vulnerabilities though not sure if CRIME, TLS includes BREACH ?

dev ssllabs SSL Server Test: cloudflare.com (Powered by Qualys SSL Labs)

cloudflare testssl excerpt for vulnerabilities test

Code (Text):

 Testing vulnerabilities

 Heartbleed (CVE-2014-0160)                not vulnerable (OK), no heartbeat extension
 CCS (CVE-2014-0224)                       not vulnerable (OK)
 Secure Renegotiation (CVE-2009-3555)      not vulnerable (OK)
 Secure Client-Initiated Renegotiation     VULNERABLE (NOT ok), potential DoS threat
 CRIME, TLS (CVE-2012-4929)                not vulnerable (OK) (not using HTTP anyway)
 POODLE, SSL (CVE-2014-3566)               not vulnerable (OK)
 TLS_FALLBACK_SCSV (RFC 7507),             Downgrade attack prevention supported (OK)
 FREAK (CVE-2015-0204)                     not vulnerable (OK)
 DROWN (2016-0800, CVE-2016-0703)          not vulnerable on this port (OK)
                                           make sure you don't use this certificate elsewhere with SSLv2 enabled services
                                           https://censys.io/ipv4?q=BAD392E96D1E8C5772D3AB26B5EF1034B40F760BDC6BBC075265B17020602899 SHA256 12C4A5747ED56E372C87890225E4CD51896D8EAD7D55CF76BFD19B6B746C70D0 SHA256 30BA61012FFE7CEAAF9A148A0CB0C5C852A9C04F4B1C27DB6EFA9919C7F49CCF could help you to find out
 LOGJAM (CVE-2015-4000), experimental      not vulnerable (OK), common primes not checked. See below for any DH ciphers + bit size
 BEAST (CVE-2011-3389)                     TLS1: DES-CBC3-SHA AES128-SHA
                                                 AES256-SHA ECDHE-RSA-DES-CBC3-SHA ECDHE-RSA-AES128-SHA
                                                 ECDHE-RSA-AES256-SHA
                                           VULNERABLE -- but also supports higher protocols (possible mitigation): TLSv1.1 TLSv1.2
 RC4 (CVE-2013-2566, CVE-2015-2808)        no RC4 ciphers detected (OK)

Spoiler: click to expand testssl full results

Code (Text):

###########################################################
    testssl       2.8pre1 from https://testssl.sh/
    (1.571 2017/02/24 15:30:28)

      This program is free software. Distribution and
             modification under GPLv2 permitted.
      USAGE w/o ANY WARRANTY. USE IT AT YOUR OWN RISK!

       Please file bugs @ https://testssl.sh/bugs/

###########################################################

 Using "OpenSSL 1.0.2-chacha (1.0.2k-dev)" [~183 ciphers]
 on 2570dffad70d:/usr/local/http2-15/bin/openssl
 (built: "reproducible build, date unspecified", platform: "linux-x86_64")


Testing all IPv4 addresses (port 443): 198.41.215.162 198.41.214.162
----------------------------------------------------------------------------------------------------------------------------------------------------------------------
 Start 2017-03-07 13:50:20    -->> 198.41.215.162:443 (cloudflare.com) <<--

 further IP addresses:   198.41.214.162 2400:cb00:2048:1::c629:d7a2 2400:cb00:2048:1::c629:d6a2
 rDNS (198.41.215.162):  --
 Service detected:       Couldn't determine what's running on port 443, assuming no HTTP service => skipping all HTTP checks


 Testing protocols (via sockets except TLS 1.2, SPDY+HTTP2)

 SSLv2               not offered (OK)
 SSLv3               not offered (OK)
 TLS 1               offered
 TLS 1.1             offered
 TLS 1.2             offered (OK)
 Version tolerance   downgraded to TLSv1.2 (OK)
 SPDY/NPN            (SPDY is an HTTP protocol and thus not tested here)
 HTTP2/ALPN          (HTTP/2 is a HTTP protocol and thus not tested here)


 Testing ~standard cipher lists

 Null Ciphers                 not offered (OK)
 Anonymous NULL Ciphers       not offered (OK)
 Anonymous DH Ciphers         not offered (OK)
 40 Bit encryption            not offered (OK)
 56 Bit export ciphers        not offered (OK)
 Export Ciphers (general)     not offered (OK)
 Low (<=64 Bit)               not offered (OK)
 DES Ciphers                  not offered (OK)
 "Medium" grade encryption    not offered (OK)
 Triple DES Ciphers           not offered (OK)
 High grade encryption        offered (OK)


 Testing robust (perfect) forward secrecy, (P)FS -- omitting Null Authentication/Encryption, 3DES, RC4

 PFS is offered (OK)          ECDHE-ECDSA-AES128-GCM-SHA256 ECDHE-ECDSA-AES128-SHA256 ECDHE-ECDSA-AES256-GCM-SHA384 ECDHE-ECDSA-AES256-SHA384 ECDHE-ECDSA-CHACHA20-POLY1305-OLD ECDHE-RSA-AES128-GCM-SHA256 ECDHE-RSA-AES128-SHA256 ECDHE-RSA-AES128-SHA ECDHE-RSA-AES256-GCM-SHA384 ECDHE-RSA-AES256-SHA384 ECDHE-RSA-AES256-SHA ECDHE-RSA-CHACHA20-POLY1305-OLD
 Elliptic curves offered:     prime256v1


 Testing server preferences

 Has server cipher order?     yes (OK)
 Negotiated protocol          TLSv1.2
 Negotiated cipher            ECDHE-ECDSA-CHACHA20-POLY1305-OLD, 256 bit ECDH
 Cipher order
    TLSv1:     ECDHE-RSA-AES128-SHA AES128-SHA ECDHE-RSA-AES256-SHA AES256-SHA ECDHE-RSA-DES-CBC3-SHA DES-CBC3-SHA
    TLSv1.1:   ECDHE-RSA-AES128-SHA AES128-SHA ECDHE-RSA-AES256-SHA AES256-SHA
    TLSv1.2:   ECDHE-ECDSA-CHACHA20-POLY1305-OLD ECDHE-ECDSA-AES128-GCM-SHA256 ECDHE-ECDSA-AES128-SHA256 ECDHE-ECDSA-AES128-SHA ECDHE-ECDSA-AES256-GCM-SHA384 ECDHE-ECDSA-AES256-SHA384 ECDHE-ECDSA-AES256-SHA
     SPDY/NPN: (SPDY is an HTTP protocol and thus not tested here)


 Testing server defaults (Server Hello)

 TLS extensions (standard)    "renegotiation info/#65281" "EC point formats/#11" "session ticket/#35" "status request/#5" "server name/#0" "application layer protocol negotiation/#16" "next protocol/#13172"
 Session Tickets RFC 5077     64800 seconds (PFS requires session ticket keys to be rotated <= daily)
 SSL Session ID support       yes
 TLS clock skew               random values, no fingerprinting possible

  Server Certificate #1
   Signature Algorithm          SHA256 with RSA
   Server key size              RSA 2048 bits
   Fingerprint / Serial         SHA1 2940BC13ECF7DAF30B9084CC734C3B971D73B3BB / 01BFD1DC15006E0ABBA7C670FF5E1101
                                SHA256 30BA61012FFE7CEAAF9A148A0CB0C5C852A9C04F4B1C27DB6EFA9919C7F49CCF
   Common Name (CN)             "cloudflare.com"
   subjectAltName (SAN)         "cloudflare.com" "www.cloudflare.com"
   Issuer                       "DigiCert SHA2 Extended Validation Server CA" ("DigiCert Inc" from "US")
   Trust (hostname)             Ok via SAN and CN (works w/o SNI)
   Chain of trust               "/usr/bin/etc/*.pem" cannot be found / not readable
   EV cert (experimental)       yes
   Certificate Expiration       604 >= 60 days (2016-10-28 00:00 --> 2018-11-02 12:00 +0000)
   # of certificates provided   2
   Certificate Revocation List  http://crl3.digicert.com/sha2-ev-server-g1.crl
   OCSP URI                     http://ocsp.digicert.com
   OCSP stapling                offered

  Server Certificate #2
   Signature Algorithm          ECDSA with SHA256
   Server key size              ECDSA 256 bits
   Fingerprint / Serial         SHA1 D4ADAB1B95728D3D6E264A7070B11E882FCA7167 / 03613EFFC0FB82D6A4D8458E8F18043A
                                SHA256 12C4A5747ED56E372C87890225E4CD51896D8EAD7D55CF76BFD19B6B746C70D0
   Common Name (CN)             "cloudflare.com"
   subjectAltName (SAN)         "cloudflare.com" "www.cloudflare.com"
   Issuer                       "DigiCert ECC Extended Validation Server CA" ("DigiCert Inc" from "US")
   Trust (hostname)             Ok via SAN and CN (works w/o SNI)
   Chain of trust               "/usr/bin/etc/*.pem" cannot be found / not readable
   EV cert (experimental)       yes
   Certificate Expiration       604 >= 60 days (2016-10-28 00:00 --> 2018-11-02 12:00 +0000)
   # of certificates provided   2
   Certificate Revocation List  http://crl3.digicert.com/DigiCertECCExtendedValidationServerCA.crl
   OCSP URI                     http://ocsp.digicert.com
   OCSP stapling                offered

  Server Certificate #3 (in response to request w/o SNI)
   Signature Algorithm          SHA1 with RSA
   Server key size              RSA 2048 bits
   Fingerprint / Serial         SHA1 D572871BB4A72BBF4D59A7FE465FCA0299F0AEB7 / 05C3D9EBE33EFDCD6C9777A694AEC7E5
                                SHA256 BAD392E96D1E8C5772D3AB26B5EF1034B40F760BDC6BBC075265B17020602899
   Common Name (CN)             "cloudflare.com"
   subjectAltName (SAN)         "cloudflare.com" "www.cloudflare.com"
   Issuer                       "Compatibility Intermediate CA" ("PKI Services" from "US")
   Trust (hostname)             Ok via SAN and CN
   Chain of trust               "/usr/bin/etc/*.pem" cannot be found / not readable
   EV cert (experimental)       no
   Certificate Expiration       518 >= 60 days (2016-11-04 00:00 --> 2018-08-08 12:00 +0000)
   # of certificates provided   2
   Certificate Revocation List  http://crl3.digicert.com/CompatibilityIntermediateCA.crl
   OCSP URI                     http://ocsp.digicert.com
   OCSP stapling                offered


 Testing vulnerabilities

 Heartbleed (CVE-2014-0160)                not vulnerable (OK), no heartbeat extension
 CCS (CVE-2014-0224)                       not vulnerable (OK)
 Secure Renegotiation (CVE-2009-3555)      not vulnerable (OK)
 Secure Client-Initiated Renegotiation     VULNERABLE (NOT ok), potential DoS threat
 CRIME, TLS (CVE-2012-4929)                not vulnerable (OK) (not using HTTP anyway)
 POODLE, SSL (CVE-2014-3566)               not vulnerable (OK)
 TLS_FALLBACK_SCSV (RFC 7507),             Downgrade attack prevention supported (OK)
 FREAK (CVE-2015-0204)                     not vulnerable (OK)
 DROWN (2016-0800, CVE-2016-0703)          not vulnerable on this port (OK)
                                           make sure you don't use this certificate elsewhere with SSLv2 enabled services
                                           https://censys.io/ipv4?q=BAD392E96D1E8C5772D3AB26B5EF1034B40F760BDC6BBC075265B17020602899 SHA256 12C4A5747ED56E372C87890225E4CD51896D8EAD7D55CF76BFD19B6B746C70D0 SHA256 30BA61012FFE7CEAAF9A148A0CB0C5C852A9C04F4B1C27DB6EFA9919C7F49CCF could help you to find out
 LOGJAM (CVE-2015-4000), experimental      not vulnerable (OK), common primes not checked. See below for any DH ciphers + bit size
 BEAST (CVE-2011-3389)                     TLS1: DES-CBC3-SHA AES128-SHA
                                                 AES256-SHA ECDHE-RSA-DES-CBC3-SHA ECDHE-RSA-AES128-SHA
                                                 ECDHE-RSA-AES256-SHA
                                           VULNERABLE -- but also supports higher protocols (possible mitigation): TLSv1.1 TLSv1.2
 RC4 (CVE-2013-2566, CVE-2015-2808)        no RC4 ciphers detected (OK)


 Testing all 183 locally available ciphers against the server, ordered by encryption strength

Hexcode  Cipher Suite Name (OpenSSL)       KeyExch.  Encryption Bits
------------------------------------------------------------------------
 xcc14   ECDHE-ECDSA-CHACHA20-POLY1305-OLD ECDH 256   ChaCha20  256
 xcc13   ECDHE-RSA-CHACHA20-POLY1305-OLD   ECDH 256   ChaCha20  256
 xc030   ECDHE-RSA-AES256-GCM-SHA384       ECDH 256   AESGCM    256
 xc02c   ECDHE-ECDSA-AES256-GCM-SHA384     ECDH 256   AESGCM    256
 xc028   ECDHE-RSA-AES256-SHA384           ECDH 256   AES       256
 xc024   ECDHE-ECDSA-AES256-SHA384         ECDH 256   AES       256
 xc014   ECDHE-RSA-AES256-SHA              ECDH 256   AES       256
 x9d     AES256-GCM-SHA384                 RSA        AESGCM    256
 x3d     AES256-SHA256                     RSA        AES       256
 x35     AES256-SHA                        RSA        AES       256
 xc02f   ECDHE-RSA-AES128-GCM-SHA256       ECDH 256   AESGCM    128
 xc02b   ECDHE-ECDSA-AES128-GCM-SHA256     ECDH 256   AESGCM    128
 xc027   ECDHE-RSA-AES128-SHA256           ECDH 256   AES       128
 xc023   ECDHE-ECDSA-AES128-SHA256         ECDH 256   AES       128
 xc013   ECDHE-RSA-AES128-SHA              ECDH 256   AES       128

Centmin Mod default HTTP/2 HTTPS testssl excerpt

Code (Text):

Testing vulnerabilities

 Heartbleed (CVE-2014-0160)                not vulnerable (OK), no heartbeat extension
 CCS (CVE-2014-0224)                       not vulnerable (OK)
 Secure Renegotiation (CVE-2009-3555)      not vulnerable (OK)
 Secure Client-Initiated Renegotiation     VULNERABLE (NOT ok), potential DoS threat
 CRIME, TLS (CVE-2012-4929)                not vulnerable (OK) (not using HTTP anyway)
 POODLE, SSL (CVE-2014-3566)               not vulnerable (OK)
 TLS_FALLBACK_SCSV (RFC 7507),             Downgrade attack prevention supported (OK)
 FREAK (CVE-2015-0204)                     not vulnerable (OK)
 DROWN (2016-0800, CVE-2016-0703)          not vulnerable on this port (OK)
                                           make sure you don't use this certificate elsewhere with SSLv2 enabled services
                                           https://censys.io/ipv4?q=A1039C3118E5828DE5ADAA27975F8FA96B55D83258BEBD3AEAD559F320AA9F73 could help you to find out
 LOGJAM (CVE-2015-4000), experimental      not vulnerable (OK), common primes not checked. See below for any DH ciphers + bit size
 BEAST (CVE-2011-3389)                     TLS1: ECDHE-RSA-AES128-SHA
                                           VULNERABLE -- but also supports higher protocols (possible mitigation): TLSv1.1 TLSv1.2
 RC4 (CVE-2013-2566, CVE-2015-2808)        no RC4 ciphers detected (OK)


 Testing all 183 locally available ciphers against the server, ordered by encryption strength

Hexcode  Cipher Suite Name (OpenSSL)       KeyExch.  Encryption Bits
------------------------------------------------------------------------
 xcc13   ECDHE-RSA-CHACHA20-POLY1305-OLD   ECDH 256   ChaCha20  256
 xc030   ECDHE-RSA-AES256-GCM-SHA384       ECDH 256   AESGCM    256
 xc028   ECDHE-RSA-AES256-SHA384           ECDH 256   AES       256
 xc02f   ECDHE-RSA-AES128-GCM-SHA256       ECDH 256   AESGCM    128
 xc027   ECDHE-RSA-AES128-SHA256           ECDH 256   AES       128
 xc013   ECDHE-RSA-AES128-SHA              ECDH 256   AES       128

cloudflare (left) vs centmin mod http/2 https defaults (right) for dev ssllabs results. Centmin Mod HTTP/2 HTTPS generated vhosts default to disable HSTS as that forces HTTPS on revisits something end users will need to decide for themselves if they want to disable.



Edit: also nice article at https://www.sjoerdlangkemper.nl/2016/11/07/current-state-of-breach-attack/

TLS 1.3 will have more protections for such, Cloudflare already enables TLS 1.3 but Chrome has temporarily disabled TLS 1.3 due to issues with connection hangs. OpenSSL isn't due to add TLS 1.3 support until OpenSSL 1.1.1 comes so current LibreSSL and OpenSSL 1.0.2/1.1.0 doesn't support TLS 1.3. So Nginx can't use TLS 1.3 for HTTPS until OpenSSL 1.1.1 comes around.