SNI Routing with BIG-IP
In the previous article, The Three HTTP Routing Patterns, Lori MacVittie covers 3 methods of routing. Today we will look at Server Name Indication (SNI) routing as an additional method of routing HTTPS or any protocol that uses TLS and SNI. Using SNI we can route traffic to a destination without having to terminate the SSL connection. This enables several benefits including: Reduced number of Public IPs Simplified configuration More intelligent routing of TLS traffic Terminating SSL Connections When you havea SSL certificate and key you can perform the cryptographic actions required to encrypt traffic using TLS. This is what I refer to as “terminating the SSL connection” throughout this article. When you want to route traffic this is a chickenand an egg problem, becausefor TLS traffic you want to be able to route the traffic by being able to inspect the contents, but this normally requires being able to “terminate the SSL connection”. The goal of this article is to layer in traffic routing for TLS traffic without having to require having/knowing the original SSL certificate and key. Server Name Indication (SNI) SNI is a TLS extension that makes it possible to "share" certificates on a single IP address. This is possible due to a client using a TLS extension that requests a specific name before the server responds with a SSL certificate. Prior to SNI, the other options would be a wildcard certificate or Subject Alternative Name (SAN) that allows you to specify multiple names with a single certificate. SNI with Virtual Servers It has been possible to use SNI on F5 BIG-IP since TMOS 11.3.0. The following KB13452 outlines how it can be configured. In this scenario (from the KB article) the BIG-IP is terminating the SSL connection. Not all clients support SNI and you will always need to specify a “fallback” profile that will be used if a SNI name is not used or matched. The next example will look at how to use SNI without terminating the SSL connection. SNI Routing Occasionally you may have the need to have a hybrid configuration of terminating SSL connections on the BIG-IP and sending connections without terminating SSL. One method is to create two separate virtual servers, one for SSL connections that the BIG-IP will handle (using clientssl profile) and one that it will not handle SSL (just TCP). This works OK for a small number of backends, but does not scale well if you have many backends (run out of Public IP addresses). Using SNI Routing we can handle everything on a single virtual server / Public IP address. There are 3 methods for performing SNI Routing with BIG-IP iRule with binary scan a. Article by Colin Walker code attribute to Joel Moses b. Code Share by Stanislas Piron iRule with SSL::extensions Local Traffic Policy Option #1 is for folks that prefer complete control of the TLS protocol. It only requires the use of a TCP profile. Options #2 and #3 only require the use of a SSL persistence profile and TCP profile. SNI Routing with Local Traffic Policy We will skip option #1 and #2 in this article and look at using a Local Traffic Policy for SNI Routing. For a review of Local Traffic Policies check out the following DevCentral articles: LTM Policy Jan 2015 Simplifying Local Traffic Policies in BIG-IP 12.1 June 2016 In previous articles about Local Traffic Policiesthe focus was on routing HTTP traffic, but today we will use it to route SSL connections using SNI. In the following example, using a Local Traffic Policy named “sni_routing”, we are setting a condition on the SSL Extension “servername” and sending the traffic to a pool without terminating the SSL connection. The pool member could be another server or another BIG-IP device. The next example will forward the traffic to another virtual server that is configured with a clientssl profile. This uses VIP targeting to send traffic to another virtual server on the same device. In both examples it is important to note that the “condition”/“action” has been changed from occurring on “request” (that maps to a HTTP L7 request) to “ssl client hello”. By performing the action prior to any L7 functions occurring, we can forward the traffic without terminating the SSL connection. The previous example policy, “sni_routing”, can be attached to a Virtual Server that only has a TCP profile and SSL persistence profile. No HTTP or clientssl profile is required! This method can also be used to solve the issue of how to consolidate multiple SSL virtual servers behind a single virtual server that have different APM and/or ASM policies. This is similar to the architecture that is used by the Container Connector for Cloud Foundry; in creating a two-tier load balancing solution on a single device. Routed Correctly? TLS 1.3 has interesting proposals on how to obscure the servername (TLS in TLS?), but for now this is a useful and practical method of handling multiple SSL certs on a single IP. In the future this may still be possible as well with TLS 1.3. For example the use of a HTTP Fronting service could be a tier 1 virtual server (this is just my personal speculation, I have not tried, at the time of publishing this was still a draft proposal). In other news it has been demonstrated that a combination of using SNI and a different host header can be used for “domain fronting”. A method to enforce consistent policy (prevent domain fronting) would be to layer in additional conditions that match requested SNI servername (TLS extension) with requested HOST header (L7 HTTP header). This would help enforce that a tenant is using a certificate that is associated with their application and not “borrowing” the name and certificate that is being used by an adjacent service. We don’t think of a TLS extension as an attribute that can be used to route application traffic, but it is useful and possible on BIG-IP.
TLS server_name extension based routing without clientssl profile
Problem this snippet solves: Some configuration requires to not decrypt SSL traffic on F5 appliances to select pool based on HTTP Host header. I found a useful irule and this code keeps the structure and most of binary commands of it. I'm not sure if the first author was Kevin Stewart or Colin Walker. thanks both of them to have provided such code. I worked to understand it reading TLS 1.2 RFC 5246 and TLS 1.3 draft-23 and provided some enhancements and following description with irule variables references. According to TLS 1.3 draft-23, this code will still be valid with next TLS version. the following network diagram shows one use cases where this code will help. This diagram show how this code works based on the tls_servername_routing_dg Datagroup values and detected server name and TLS versions detected in the CLIENT_HELLO packet. For performances reasons, only the first TCP data packet is analyzed. Versions : 1.1 : Updated to support TLS version detection and SSL offload feature. (05/03/2018) 1.2 : Updated to support TLS Handshake Failure Messages instead of reject. (09/03/2018) 1.3 : Updated to support node forwarding, logs only for debug (disabled with static variable), and changed the Datagroup name to tls_servername_routing_dg . (16/03/2018) 1.4 : Added 16K handshake length limit defined in RFC 1.2 in variable payload. (13/04/2018) 1.5 : Added supported version extension recursion, to bypass unknown TLS version if a known and allowed version is in the list. This correct an issue with Google chrome which include not documented TLS version on top of the list. (30/04/2018) How to use this snippet: create a virtual server with following configuration: type : Standard SSL Profile (client) : Only if you want to enable SSL offload for some pools irule : code bellow create all objects used in following datagroup (virtual servers, pools) create a data-group named tls_servername_routing_dg. if you want to forward to pool, add the value pool NameOfPool if you want to forward to pool and enable SSL Offload (ClientSSL profile must be enabled on virtual server), add the value pool NameOfPool ssl_offload if you want to forward to virtual server, add the value virtual NameOfVirtual if you want to forward to an IP address, add the value node IPOfServer , backend server will not be translated if you want to reject the connection with RFC compliant handshake_failure message, add the value handshake_failure if you want to reject the connection, add the value reject if you want to drop the connection, add the value drop The default value keyword is search if there is no TLS server name extension or if TLS server name extension is not found in the data group. here is an example: ltm data-group internal tls_servername_routing_dg { records { app1.company.com { data "virtual vs_app1.company.com" } app2.company.com { data "pool p_app2" } app3.company.com { data "pool p_app3 ssl_offload" } app4.company.com { reject } default { data "handshake_failure" } } type string } Code : when RULE_INIT { set static::sni_routing_debug 0 } when CLIENT_ACCEPTED { if { [PROFILE::exists clientssl] } { # We have a clientssl profile attached to this VIP but we need # to find an SNI record in the client handshake. To do so, we'll # disable SSL processing and collect the initial TCP payload. set ssldisable "SSL::disable" set sslenable "SSL::enable" eval $ssldisable } TCP::collect set default_pool [LB::server pool] set tls_servername "" set tls_handshake_prefered_version "0000" } when CLIENT_DATA { # Store TCP Payload up to 2^14 + 5 bytes (Handshake length is up to 2^14) set payload [TCP::payload 16389] set payloadlen [TCP::payload length] # - Record layer content-type (1 byte) --> variable tls_record_content_type # Handshake value is 22 (required for CLIENT_HELLO packet) # - SSLv3 / TLS version. (2 byte) --> variable tls_version # SSLv3 value is 0x0300 (doesn't support SNI, not valid in first condition) # TLS_1.0 value is 0x0301 # TLS_1.1 value is 0x0302, 0x0301 in CLIENT_HELLO handskake packet for backward compatibility (not specified in RFC, that's why the value 0x0302 is allowed in condition) # TLS_1.2 value is 0x0303, 0x0301 in CLIENT_HELLO handskake packet for backward compatibility (not specified in RFC, that's why the value 0x0303 is allowed in condition) # TLS_1.3 value is 0x0304, 0x0301 in CLIENT_HELLO handskake packet for backward compatibility (explicitly specified in RFC) # TLS_1.3 drafts values are 0x7FXX (XX is the hexadecimal encoded draft version), 0x0301 in CLIENT_HELLO handskake packet for backward compatibility (explicitly specified in RFC) # - Record layer content length (2 bytes) : must match payload length --> variable tls_recordlen # - TLS Hanshake protocol (length defined by Record layer content length value) # - Handshake action (1 byte) : CLIENT_HELLO = 1 --> variable tls_handshake_action # - handshake length (3 bytes) # - SSL / TLS handshake version (2 byte) # In TLS 1.3 CLIENT_HELLO handskake packet, TLS hanshake version is sent whith 0303 (TLS 1.2) version for backward compatibility. a new TLS extension add version negociation. # - hanshake random (32 bytes) # - handshake sessionID length (1 byte) --> variable tls_handshake_sessidlen # - handshake sessionID (length defined by sessionID length value, max 32-bit) # - CipherSuites length (2 bytes) --> variable tls_ciphlen # - CipherSuites (length defined by CipherSuites length value) # - Compression length (2 bytes) --> variable tls_complen # - Compression methods (length defined by Compression length value) # - Extensions # - Extension length (2 bytes) --> variable tls_extension_length # - list of Extensions records (length defined by extension length value) # - extension record type (2 bytes) : server_name = 0, supported_versions = 43--> variable tls_extension_type # - extension record length (2 bytes) --> variable tls_extension_record_length # - extension data (length defined by extension record length value) # # TLS server_name extension data format: # - SNI record length (2 bytes) # - SNI record data (length defined by SNI record length value) # - SNI record type (1 byte) # - SNI record value length (2 bytes) # - SNI record value (length defined by SNI record value length value) --> variable tls_servername # # TLS supported_version extension data format (added in TLS 1.3): # - supported version length (1 bytes) --> variable tls_supported_versions_length # - List of supported versions (2 bytes per version) --> variable tls_supported_versions # If valid TLS 1.X CLIENT_HELLO handshake packet if { [binary scan $payload cH4Scx3H4x32c tls_record_content_type tls_version tls_recordlen tls_handshake_action tls_handshake_version tls_handshake_sessidlen] == 6 && \ ($tls_record_content_type == 22) && \ ([string match {030[1-3]} $tls_version]) && \ ($tls_handshake_action == 1) && \ ($payloadlen == $tls_recordlen+5)} { # store in a variable the handshake version set tls_handshake_prefered_version $tls_handshake_version # skip past the session id set record_offset [expr {44 + $tls_handshake_sessidlen}] # skip past the cipher list binary scan $payload @${record_offset}S tls_ciphlen set record_offset [expr {$record_offset + 2 + $tls_ciphlen}] # skip past the compression list binary scan $payload @${record_offset}c tls_complen set record_offset [expr {$record_offset + 1 + $tls_complen}] # check for the existence of ssl extensions if { ($payloadlen > $record_offset) } { # skip to the start of the first extension binary scan $payload @${record_offset}S tls_extension_length set record_offset [expr {$record_offset + 2}] # Check if extension length + offset equals payload length if {$record_offset + $tls_extension_length == $payloadlen} { # for each extension while { $record_offset < $payloadlen } { binary scan $payload @${record_offset}SS tls_extension_type tls_extension_record_length if { $tls_extension_type == 0 } { # if it's a servername extension read the servername # SNI record value start after extension type (2 bytes), extension record length (2 bytes), record type (2 bytes), record type (1 byte), record value length (2 bytes) = 9 bytes binary scan $payload @[expr {$record_offset + 9}]A[expr {$tls_extension_record_length - 5}] tls_servername set record_offset [expr {$record_offset + $tls_extension_record_length + 4}] } elseif { $tls_extension_type == 43 } { # if it's a supported_version extension (starting with TLS 1.3), extract supported version in a list binary scan $payload @[expr {${record_offset} + 4}]cS[expr {($tls_extension_record_length -1)/2}] tls_supported_versions_length tls_supported_versions set tls_handshake_prefered_version [list] foreach version $tls_supported_versions { lappend tls_handshake_prefered_version [format %04X [expr { $version & 0xffff }] ] } if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : prefered version list : $tls_handshake_prefered_version"} set record_offset [expr {$record_offset + $tls_extension_record_length + 4}] } else { # skip over other extensions set record_offset [expr {$record_offset + $tls_extension_record_length + 4}] } } } } } elseif { [binary scan $payload cH4 ssl_record_content_type ssl_version] == 2 && \ ($tls_record_content_type == 22) && \ ($tls_version == 0300)} { # SSLv3 detected set tls_handshake_prefered_version "0300" } elseif { [binary scan $payload H2x1H2 ssl_version handshake_protocol_message] == 2 && \ ($ssl_version == 80) && \ ($handshake_protocol_message == 01)} { # SSLv2 detected set tls_handshake_prefered_version "0200" } unset -nocomplain payload payloadlen tls_record_content_type tls_recordlen tls_handshake_action tls_handshake_sessidlen record_offset tls_ciphlen tls_complen tls_extension_length tls_extension_type tls_extension_record_length tls_supported_versions_length tls_supported_versions foreach version $tls_handshake_prefered_version { switch -glob -- $version { "0200" { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : SSLv2 ; connection is rejected"} reject return } "0300" - "0301" { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : SSL/TLS ; connection is rejected (0x$version)"} # Handshake Failure packet format: # # - Record layer content-type (1 byte) --> variable tls_record_content_type # Alert value is 21 (required for Handshake Failure packet) # - SSLv3 / TLS version. (2 bytes) --> from variable tls_version # - Record layer content length (2 bytes) : value is 2 for Alert message # - TLS Message (length defined by Record layer content length value) # - Level (1 byte) : value is 2 (fatal) # - Description (1 bytes) : value is 40 (Handshake Failure) TCP::respond [binary format cH4Scc 21 $tls_version 2 2 40] after 10 TCP::close #drop #reject return } "030[2-9]" - "7F[0-9A-F][0-9A-F]" { # TLS version allowed, do nothing break } "0000" { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : No SSL/TLS protocol detected ; connection is rejected (0x$version)"} reject return } default { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : Unknown CLIENT_HELLO TLS handshake prefered version : 0x$version"} } } } if { $tls_servername equals "" || ([set sni_dg_value [class match -value [string tolower $tls_servername] equals tls_servername_routing_dg]] equals "")} { set sni_dg_value [class match -value "default" equals tls_servername_routing_dg] } switch [lindex $sni_dg_value 0] { "virtual" { if {[catch {virtual [lindex $sni_dg_value 1]}]} { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; Virtual server [lindex $sni_dg_value 1] doesn't exist"} } else { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; forwarded to Virtual server [lindex $sni_dg_value 1]"} } } "pool" { if {[catch {pool [lindex $sni_dg_value 1]}]} { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; Pool [lindex $sni_dg_value 1] doesn't exist"} } else { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; forwarded to Pool [lindex $sni_dg_value 1]"} } if {[lindex $sni_dg_value 2] equals "ssl_offload" && [info exists sslenable]} { eval $sslenable } } "node" { if {[catch {node [lindex $sni_dg_value 1]}]} { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; Invalid Node value [lindex $sni_dg_value 1]"} } else { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; forwarded to Node [lindex $sni_dg_value 1]"} } } "handshake_failure" { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; connection is rejected (with Handshake Failure message)"} TCP::respond [binary format cH4Scc 21 $tls_handshake_prefered_version 2 2 40] after 10 TCP::close return } "reject" { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; connection is rejected"} reject return } "drop" { if {$static::sni_routing_debug} {log local0. "[IP::remote_addr] : TLS server_name value = ${tls_servername} ; TLS prefered version = 0x${tls_handshake_prefered_version} ; connection is dropped"} drop return } } TCP::release }Serverside SNI injection iRule
Problem this snippet solves: Hi Folks, the iRule below can be used to inject a TLS SNI extension to the server side based on e.g. HOST-Header values. The iRule is usefull if your pool servers depending on valid SNI records and you don't want to configure dedicated Server SSL Profiles for each single web application. Cheers, Kai How to use this snippet: Attach the iRule to the Virtual Server where you need to insert a TLS SNI expension Tweak the $sni_value variable within the HTTP_REQUEST to meet your requirements or move it to a different event as needed. Make sure you've cleared the "Server Name" option in your Server_SSL_Profile. Code : when HTTP_REQUEST { #Set the SNI value (e.g. HTTP::host) set sni_value [getfield [HTTP::host] ":" 1] } when SERVERSSL_CLIENTHELLO_SEND { # SNI extension record as defined in RFC 3546/3.1 # # - TLS Extension Type = int16( 0 = SNI ) # - TLS Extension Length = int16( $sni_length + 5 byte ) # - SNI Record Length = int16( $sni_length + 3 byte) # - SNI Record Type = int8( 0 = HOST ) # - SNI Record Value Length = int16( $sni_length ) # - SNI Record Value = str( $sni_value ) # # Calculate the length of the SNI value, Compute the SNI Record / TLS extension fields and add the result to the SERVERSSL_CLIENTHELLO SSL::extensions insert [binary format SSScSa* 0 [expr { [set sni_length [string length $sni_value]] + 5 }] [expr { $sni_length + 3 }] 0 $sni_length $sni_value] } Tested this on version: 12.0
APM :: Portal Access Lists :: SNI & HTTP
I'm trying to create a Portal Access List with a few web resources, and one of the links does not work because it is an Apache server that is validating that the SNI and HTTP hostname match. The problem is, that when the user logs into APM and launches the web link, they are launching a request to the APM and not the backend server... therefore the SNI is for APM and does not match the HTTP hostname in the header (which is specified in the Portal Access link via Application URI). [ssl:error] [pid 11111] AH02032: Hostname xxx.yyy.com provided via SNI and hostname aaa.bbb.com provided via HTTP are different From what I've read, this cannot be disabled on the Apache server without removing SNI and recompiling... which is not an option for me. However this F5 use-case seems like it would be fairly common, so I'm not sure what I'm missing here. Anybody have any thoughts? Thanks-
BIG-IP DNS SNI monitoring
We are trying to get a SNI monitor to work on a BIG-IP DNS to a generic host. Using the external ADFS monitors the checks fail. When running a CURL to the destination servers we receive Unknown SSL protocol error in connection while a openssl test returns the cert and the CN we are grepping for but the moniotr still fails. We have tried with the standard ADFS external monitor provided by F5 along with the amended version for TLS1.1 and above. Also tried another custom one from Devcentral. Can anyone provide any pointers in how we could get this to work? Monitor 1: !/bin/sh These arguments supplied automatically for all external monitors: $1 = IP (nnn.nnn.nnn.nnn notation) $2 = port (decimal, host byte order) This script expects the following Name/Value pairs: HOST = the host name of the SNI-enabled site URI = the URI to request RECV = the expected response Remove IPv6/IPv4 compatibility prefix (LTM passes addresses in IPv6 format) NODE= echo ${1} | sed 's/::ffff://' if [[ $NODE =~ ^[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}$ ]]; then NODE=${NODE} else NODE=[${NODE}] fi PORT=${2} PIDFILE="/var/run/ basename ${0} .sni_monitor_${HOST}_${PORT}_${NODE}.pid" if [ -f $PIDFILE ] then echo "EAV exceeded runtime needed to kill ${HOST}:${PORT}:${NODE}" | logger -p local0.error kill -9 cat $PIDFILE > /dev/null 2>&1 fi echo "$$" > $PIDFILE (echo -e "GET $URI HTTP/1.1\r\nHost: $HOST\r\nConnection: Close\r\n\r\n"; sleep 2) | openssl s_client -cipher 'ECDHE-RSA-AES256-SHA' -servername '$HOST' STATUS=$? rm -f $PIDFILE if [ $STATUS -eq 0 ] then echo "UP" fi exit Monitor 2 !/bin/sh These arguments supplied automatically for all external monitors: $1 = IP (nnn.nnn.nnn.nnn notation) $2 = port (decimal, host byte order) This script expects the following Name/Value pairs: HOST = the host name of the SNI-enabled site URI = the URI to request RECV = the expected response Remove IPv6/IPv4 compatibility prefix (LTM passes addresses in IPv6 format) NODE= echo ${1} | sed 's/::ffff://' if [[ $NODE =~ ^[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}$ ]]; then NODE=${NODE} else NODE=[${NODE}] fi PORT=${2} PIDFILE="/var/run/ basename ${0} .sni_monitor_${HOST}_${PORT}_${NODE}.pid" if [ -f $PIDFILE ] then echo "EAV exceeded runtime needed to kill ${HOST}:${PORT}:${NODE}" | logger -p local0.error kill -9 cat $PIDFILE > /dev/null 2>&1 fi echo "$$" > $PIDFILE curl-apd -k -i --resolve $HOST:$PORT:$NODE https://$HOST$URI | grep -i "${RECV}" > /dev/null 2>&1 STATUS=$? rm -f $PIDFILE if [ $STATUS -eq 0 ] then echo "UP" fi exit Monitor 3 !/bin/bash pidfile="/var/run/$MONITOR_NAME.$1..$2.pid" if [ -f $pidfile ] then kill -9 - cat $pidfile > /dev/null 2>&1 fi echo "$$" > $pidfile node_ip= echo $1 |sed 's/::ffff://' node_port=$2 getscript () { echo 'GET / HTTP/1.1' echo 'Host: ..*.com' echo '' while sleep 0; do echo 'quit\n' done } docurl () { IFS=$'\n' arr=($(getscript | openssl s_client -connect ...:443 -servername ...com 2>/dev/nul |grep -E CN=...com)) unset IFS } docurl echo ${arr[0]} if [ -n "${arr[0]}" ] then Remove the pidfile before the script echoes anything to stdout and is killed by bigd rm -f $pidfile echo "up" fi Remove the pidfile before the script ends rm -f $pidfileSelected client SSL does not match security policies for VS after cipher update
Hi, I'm trying to update ciphers on one of my profiles. The one I want to use is: !LOW:!SSLv2:!SSLv3:!MD5:!RC4+SHA:!EXPORT:!DHE:ECDHE+AES-GCM:ECDHE+AES:AES+SHA+RSA:@STRENGTH This works fine on another VS, but an attemtp of installing it on this one results in this error: 0107157c:3: Selected client SSL profiles do not match security policies for Virtual Server /EXTERNAL/vs_server_443. Now the OK and NOK vs are a bit different, but I can't figure out which portion of the config can be responsible for this error. Let me summarize the differences: vs_NOK_443 Protocol Profile (Client): prot_tcp_client_name_WAN (based on tcp_wan_optimized) Protocol Profile (Server): prot_tcp_client_name_LAN (based on tcp-lan-optimized) HTTP Profile: http_xff vs_OK_https Protocol Profile (Client): tcp Protocol Profile (Server): (use Client Profile) HTTP Profile: http_xff_redir-rewrite Now i do not see any difference between http-xff and http-xff_redir_rewrite is that the latter uses a Server Agent Name Both server have two client ssl profiles and the profile in question is marked as the default profile for SNI.Client SSL profiles using SNI not able to use the subject alternative name
We have a clientssl profile using a *.domain.com wildcard SSL certificate. This profile is set as the default for SNI. We also have specific clientssl profiles using the application specific SSL certificate. The application specific certs have their subject as www.application.com with the subject alternative name with application.com. There may also be several other SAN listed depending on the web app. In testing everything works great when accessing the site via https://www.application.com. However when using https://application.com we receive a cert error and the *.domain.com wildcard SSL certificate is used. This is the same for any domain listed as a SAN. My main question is can SNI use subject alternative names? My testing indicates no, but I wanted to put this out to the group. Here is my sanitized config: ltm profile client-ssl domain.com_wildcard { app-service none cert domain.com_wildcard.crt chain ComodoCA.crt defaults-from clientssl key domain.com_wildcard.key sni-default true } ltm profile client-ssl prod-www_application_com { app-service none cert prod-www_application_com.crt chain prod-www_application_com.intermediate.ca.crt key prod-www_application_com.key } ltm virtual vs-x.x.x.x_443 { destination x.x.x.x:https ip-protocol tcp mask 255.255.255.255 pool site-x.x.x.x_443 profiles { http-x-forward { } domain.com_wildcard { context clientside } prod-www_application_com { context clientside } serverssl-insecure-compatible { context serverside } tcp { } websecurity { } } source 0.0.0.0/0 source-address-translation { pool snat_pool type snat } vs-index 2539 }issue with ssl client profile when adding irule sni injection to a vs
Hello, We want to add SNI field to our MQTT/TLS trafic between clients and a broker servers (acting as servers). unfortunatelly, the client do not support SNI extension field. The F5 is acting in TLS passthrough. the broker servers are the TLS server end point. For that I use an irule with SSL::extensions insert (check below). I am creating my self the SNI extension. unfortunatelly, When adding my irule to my virtual server, I cannot validated my virtual server, i get an error that a client ssl profile is not present. here is my irule: when CLIENTSSL_CLIENTHELLO { SNI extension record as defined in RFC 3546/3.1 - TLS Extension Type = int16( 0 = SNI ) - TLS Extension Length = int16( $sni_length + 5 byte ) - SNI Record Length = int16( $sni_length + 3 byte) - SNI Record Type = int8( 0 = HOST ) - SNI Record Value Length = int16( $sni_length ) - SNI Record Value = str( $sni_value ) Calculate the length of the SNI value, Compute the SNI Record / TLS extension fields and add the result to the SERVERSSL_CLIENTHELLO SSL::extensions insert [binary format SSScSa* 0 [expr { [set sni_length [string length "testname"]] + 5 }] [expr { $sni_length + 3 }] 0 $sni_length "testname"] } I don't understand why i need to add a ssl profile to my virtual server, as F5 is TLS passthrough. thanks for your answer.
