Note : this question was sent to users@httpd.apache.org mailing list too. The inconsistencies in how mod_setenvif and mod_headers handle the REQUEST_URI are frustrating. The request header is set, replacing any previous header with this name setifempty The request header is set, but only if there is no previous header with this name. Examples of frauds discovered because someone tried to mimic a random sequence. Find centralized, trusted content and collaborate around the technologies you use most. SetEnvIf basically matches each requests attribute value with specified regex and sets matching requestss request header environment variable. Is it cheating if the proctor gives a student the answer key by mistake and the student doesn't report it? Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. echo Request headers with this name are echoed back in the response headers. did anything serious ever run on the speccy? How did muzzle-loaded rifled artillery solve the problems of the hand-held rifle? Is this an at-all realistic configuration for a DHC-2 Beaver? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. The SetEnvIf directive defines environment variables based on attributes of the request. It only takes a minute to sign up. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. *)$ X_THING=$1. (note: we cannot control how our reverse proxy works, only Apache) Could that be qualified as a bug ? Are defenders behind an arrow slit attackable? As a native speaker why is this usage of I've so awkward? Can I change Apache configuration based on requestHeaders? Always use Late mode in an operational server. Help us identify new roles for community members, Adding missing header in Apache HTTP response. How to use HTML to print header and footer on every printed page of a document? Using SetEnvIf (Apache <=2.2) Here's the syntax of SetEnvIf. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. This is a workaround for the longstanding behavior of how . My configuration now looks like this, and it works. Thats it! How could my characters be tricked into thinking they are on Mars? You could use this by specifying ^X-Forwarded-For$ which would iterate over the multiple occurrences of this 1 header. all of which exist in the parallel . If SetEnvIf sees regex-like characters in the first argument, it will go into a mode where it iterates over all headers that match the regex until there's a match. I can't really find much on this topic outside of using regex. SetEnvIf allows you to reference HTTP request headers directly, eg "Referer". To learn more, see our tips on writing great answers. Does a 120cc engine burn 120cc of fuel a minute? canvas!1apache.htaccessapacheSetEnvIfOrigin":"IS_CORSHeadersetAccess-Control-Allow-Origin"*"env=IS_CORSmod_setenvifmod_headers. If there are multiple headers of the same name, all will be removed. SetenvIf is a good apache tool to read a request header, here . In the above statements, SetEnvIf checks the Remote_addr request attribute and if it matches the specified IP then sets request header environment variable as cors. Available in 2.4.7 and later. did anything serious ever run on the speccy? Apache allows you to dynamically set request header environment variable for your website, as well as modify response headers conditionally. Why would Henry want to close the breach? Are defenders behind an arrow slit attackable? Apache: difference between "Header always set" and "Header set"? Thanks for contributing an answer to Stack Overflow! Then, using environment variables is the classical way of writing complex things in Apache (I mean the way to store some sort of variables). header may be a regular expression. Typesetting Malayalam in xelatex & lualatex gives error. The response header of this name is removed, if it exists. Is there a verb meaning depthify (getting more depth)? Then Apache will set Access-Control-Allow-Origin header of all requests whose request header environment variable is set tocors. Why did the Council of Elrond debate hiding or sending the Ring away, if Sauron wins eventually in that scenario? Can a prospective pilot be negated their certification because of too big/small hands? RewriteRule creates an environment variable that is not accessible by Allow/Deny directive . In my case, I want to limit access based on query string but SetEnvIf does not have that attribute to test against. In the above statement, an attribute can be: Bonus Read : How to Find Apache Version in Linux. The attribute specified in the first argument can be one of three things: An HTTP request header field (see RFC2616 for more information about these); for example: Host, User-Agent, Referer, and Accept-Language.A regular expression may be used to specify a set of request headers. Are the S&P 500 and Dow Jones Industrial Average securities? SetEnvIf attribute regex [! Does a 120cc engine burn 120cc of fuel a minute? IIS sets http header Expires to -1, how do I override this with mod_expires, Apache proxy_http redirect to ip and set hostname. We handle the concatenation correctly with the (,| |^) regexp trick, but the problem is that Apache seems to run the SetEnvIf only against the first occurrence of the Header. Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site, Learn more about Stack Overflow the company. So : Add the relevant Origin header in your request. Making statements based on opinion; back them up with references or personal experience. Precision : CentOS 6, Apache 2.2.15 latest patch version. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. Should teachers encourage good students to help weaker ones? Cooking roast potatoes with a slow cooked roast, If you see the "cross", you're on the right track. It seems that environment variables in Apache are not being treated equally when SetEnv, SetEnvIf and RewriteRule directives are used. Should teachers encourage good students to help weaker ones? We will look at each of them. does not work. The value part of the Header instruction is: value may be a character string, a string containing format specifiers or a combination of both. There are 3 ways to dynamically set request header environment variable in Apache. Here are the steps to set Apache header conditionally for your website. But the only format specifiers available are %% (for % ), %t for a timestamp, %D (idem), % {foo}e and % {foo}s for environments variables. There is some repetition between the two, however, there are differences. Connect and share knowledge within a single location that is structured and easy to search. Thanks. Help us identify new roles for community members, Proposing a Community-Specific Closure Reason for non-English content. The SetEnvIf directive defines environment variables based on attributes of the request. The solution for Apache 2.2.4 and below listed here Header append Access-Control-Allow-Origin "" Header edit Access-Control-Allow-Origin "^$" "*" may have a side effect of appending , to a non-empty header value because it's how append action works. The SetEnvIf directive defines environment variables based on attributes of the request. This should be documented better as a module-specific solution. It makes it difficult to use the former module to copy and correct the variable for use with the latter. When would I give a checkpoint to my D&D party that they can return to if they die? Asking for help, clarification, or responding to other answers. Bonus Read : How to Enable mod_headers in Apache in Ubuntu, Similarly, if you want to set conditional Apache header based on requested URL (e.g /product/ ) you can use the REQUEST_URI attribute, You can also set Apache header conditionally using IF..Else directive and Apache expressions. Add the port to your regex. Thus your header directive is skipped since the env variable is not set. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. This allows. rev2022.12.9.43105. Apache 2.2 (, ) SSL; : Apache2.2 . Heres how to set Apache header conditionally using SetEnvIfdirective, and IF Else condition. - [E=noxff:%{REMOTE_ADDR}] # Apache Configuration File Using `.htaccess` files slows down Apache, therefore, if you have access # to the main server config file (usually called `httpd.conf`), you should add Name of a play about the morality of prostitution (kind of). Asking for help, clarification, or responding to other answers. By the way escaping slashes is not necessary in your regex. How to set up Nginx as a caching reverse proxy? Not the answer you're looking for? The attribute specified in the first argument can be one of four things: An HTTP request header field (see RFC2616 for more information about these); for example: Host, User-Agent, Referer, and Accept-Language.A regular expression may be used to specify a set of request headers. You can also use RewriteRule to match requests and set header dynamically. Similarly, if you want to set header based on requested url (e.g /product/) you can use QUERY_STRING variable. We will look at each of them. RewriteRule . I couldn't find the right way to ask google about this and found no result. - We do not currently allow content pasted from ChatGPT on Stack Overflow; read our policy here. Examples of frauds discovered because someone tried to mimic a random sequence. If there are multiple headers of the same name, all will be removed. Try itToday! The value part of the Header instruction is: value may be a character string, a string containing format specifiers or a combination of both. Is there any reason on passenger airliners not to have a physical lock between throttles? A small bolt/nut came off my mtn bike while washing it, can someone help me identify it? This isn't so hard. ]env-variable[=value] [[! I'm trying to implement the suggestion here: https://stackoverflow.com/a/1850482/138228. How to say "patience" in latin in the modern sense of "virtue of waiting or being able to wait"? I couldn't find a away of doing this without SetEnvIf but other than that just copying a different header can be done with the following, I was doing this as part of a ReverseProxy (hence using RequestHeader instead of Header) but the two appear to be interchangeable. ]env-variable[=value]] Ready to optimize your JavaScript with Rust? The SetEnvIf directive defines environment variables based on attributes of the request. Using an environment variable in mod_headers set by mod_rewrite. Connect and share knowledge within a single location that is structured and easy to search. eg. mod_headers can be applied either early or late in the request. You can place the above linesin your servers location or directory directives, or .htaccess file. So I don't know why you would like another solution. I determined that by stripping my .htaccess file to the bone, then adding back each section until the header controls proved to be the culprit. How to smoothen the round border of a created buffer to make it look more natural? By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Problem is sometimes client have others proxies on their side and the X-Forwarded-For Header wil be either duplicated or concatenated. Does integrating PDOS give total charge of a system? By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Edit: In Apache 2.2 you should be able to do this: The following should be an equivalent to RequestHeader setIfEmpty in Apache versions <=2.4.6 (where setIfEmpty action is not supported): Thanks for contributing an answer to Server Fault! It's the case, at least, in Apache 2.4.6. without using the bad .htaccess dynamic configuration files. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. One of the following aspects of the request: The name of an environment variable in the list of those associated with the request. Should I give a brutally honest feedback on course evaluations? 127.0.0.1 ( %h) This is the IP address of the client (remote host) which made the request to the server. There are 3 ways to dynamically set request header environment variable in Apache. SetEnvIf uses Request_Protocol, but Apache Expressions use SERVER_PROTOCOL. I've also tried digging into the mod_setenvif's code but that's out of my league. Is there a syntax error or other error in this Apache site configuration? Debian/Ubuntu - Is there a man page listing all the version codenames/numbers? But the only format specifiers available are %% (for %), %t for a timestamp, %D (idem), %{foo}e and %{foo}s for environments variables. You could use this by specifying ^X-Forwarded-For$ which would iterate over the multiple occurrences of this 1 header. 1. SetenvIf is a good apache tool to read a request header, here reading the Origin header. To learn more, see our tips on writing great answers. Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide. The normal mode is late, when Request Headers are set immediately before running the content generator and Response Headers just as the response is sent down the wire. . Any idea on how to handle this kind of case ? Why does my stock Samsung Galaxy phone/tablet lack some features compared to other Samsung Galaxy models? Connecting three parallel LED strips to the same power supply, Name of a play about the morality of prostitution (kind of), Cooking roast potatoes with a slow cooked roast. i got the same answer from users@httpd.apache.org. Is there a way to read the value of a request header in Apache config? The rubber protection cover does not pass through the hole in the rim. rev2022.12.9.43105. i will test that ASAP indeed. How does the Chameleon's Arcane/Divine focus interact with magic item crafting? RequestHeader setIfEmpty X-Forwarded-For "%{noxff}e". Is there a verb meaning depthify (getting more depth)? But this has nothing to do with .htaccess, you can put such lines in regular apache configuration file (virtualhost?) If you're a seasoned HTTPD admin or an attentive reader you may have spotted the problem or at least noticed that something is wrong. Drupal CMS pdfword .htaccess pdfurl Drupal .hta Ubiqmakes it easy to visualize data in minutes, and monitor in real-time dashboards. Help us identify new roles for community members, Proposing a Community-Specific Closure Reason for non-English content, Detect apache reverse proxy programmatically, Apache HTTPD adding Full Hostname to Redirect - we want only path, Incorrect Access-Control-Allow-Origin header value with Apache reverse proxy and 304 from upstream service. I seem to be having some problems with that in apache 2.2.24. works all day long. rev2022.12.9.43105. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Apache Auth config settings override auth headers issued from PHP, How to allow incoming traffic based on User-Agent Header field with Apache. The normal mode is late, when Request Headers are set immediately before running the content generator and Response Headers just as the response is sent down the wire. What is the common header format of Python files? This argument is followed by a header name, which can include the final colon, but it is not required. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. The attribute specified in the first argument can be one of three things: An HTTP request header field (see RFC2616 for more information about these); for example: Host, User-Agent, Referer, and Accept-Language.A regular expression may be used to specify a set of request headers. Now you can dynamically set Apache headers conditionally for your websites & applications. My current Apache 2.2 SetEnvIf Remote_Addr ^107\.20\.0\.0\/14 bad_range . Why does the distance from light to subject affect exposure (inverse square law) while from subject to lens does not? Ready to optimize your JavaScript with Rust? Making statements based on opinion; back them up with references or personal experience. Share. However if one tries to use a dynamic value, RequestHeader setIfEmpty X-Forwarded-For "%{REMOTE_ADDR}e". If SetEnvIf sees regex-like characters in the first argument, it will go into a mode where it iterates over all headers that match the regex until there's a match. Here are the steps to set Apache header conditionally for your website. SetEnvIf thing ^ (. We are using this kind of configuration to grant access to one of our sites. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Sorted by: 0. Connect and share knowledge within a single location that is structured and easy to search. CGAC2022 Day 10: Help Santa sort presents! I have found that you need the help of mod_rewrite to harvest the value. What I'm looking for is something like : Header set NAME = %{value_of_different_header}%, Reading answer from : https://serverfault.com/questions/136428/header-set-access-control-allow-origin-not-working-with-mod-rewrite-mod-jk. mod_headers can be applied either early or late in the request. Would it be possible, given current technology, ten years, and an infinite amount of money, to construct a 7,000 foot (2200 meter) aircraft carrier? To subscribe to this RSS feed, copy and paste this URL into your RSS reader. SSL [hint: SSLProtocol] By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. We do not currently allow content pasted from ChatGPT on Stack Overflow; read our policy here. MOSFET is getting very hot at high frequency PWM. Heres the above example using Apache expressions, Bonus Read : How to Upgrade Apache Version in CentOS, Redhat Linux. For some reason it doesn't like "" as a regular expression but ^$ seemed to do the trick. How to print and pipe log file at the same time? Why is Singapore considered to be a dictatorial regime and a multi-party democracy at the same time? Compatibility: SetIfEmpty available in 2.4.7 and later, expr=value available in 2.4.10 and later. To learn more, see our tips on writing great answers. Just be aware that anything put in there must be sanitised, since it comes from the remote request. Documentation is unclear about this behavior. Always use Late mode in an operational server. https://stackoverflow.com/a/1850482/138228, https://serverfault.com/questions/136428/header-set-access-control-allow-origin-not-working-with-mod-rewrite-mod-jk. This is a workaround for the longstanding behavior of how many modules treat multiple occurrences. Consult http://httpd.apache.org/docs/current/expr.html for more info about the expr= syntax. Disconnect vertical tab connector from PCB. Why did the Council of Elrond debate hiding or sending the Ring away, if Sauron wins eventually in that scenario? Not the answer you're looking for? at the moment my host implemented http/2 my header control section blew up the server. Find centralized, trusted content and collaborate around the technologies you use most. Each part of this log entry is described below. Asking for help, clarification, or responding to other answers. However, you will need to enable Apachemod_rewritemodule to use rewrite rule. Thanks for contributing an answer to Stack Overflow! The attribute specified in the first argument can be one of the following things: An HTTP request header field (see RFC2616 for more information about these); for example: Host, User-Agent, Referer, and Accept-Language.A regular expression may be used to specify a set of request headers. The solution for Apache 2.2.4 and below listed here, Set header in apache if it doesn't already exist, http://httpd.apache.org/docs/current/expr.html. Making statements based on opinion; back them up with references or personal experience. I have a proxy that is injecting some headers but I want to modify it so it only sets the headers if they are not already present: In Apache 2.4.7, x86_64, Ubuntu 14.04 LTS, RequestHeader setIfEmpty X-Forwarded-For "127.0.0.1". This directive can replace, merge or remove HTTP response headers. Why do American universities have so many gen-eds? How To Install mod_evasive to Protect Against DoS and DDoS, How To Enable mod_rewrite For Apache in CentOS, How to Enable mod_headers in Apache in Ubuntu, How to Upgrade Apache Version in CentOS, Redhat Linux, 5 Top Customer Experience Software to Grow Your Brand, HTTP Request header such as Host, User-agent,etc, Server variables such as Remote_Host, Remote_Addr, etc. Sed based on 2 words, then replace whole line with variable. Early mode is designed as a test/debugging aid for developers. Why do American universities have so many gen-eds? 1 Answer. The best answers are voted up and rise to the top, Not the answer you're looking for? Something can be done or not a fit? In the above code, RewriteRule will match all URLs starting with /product/ and set their environment variable to cors. The header is modified just after the content handler and output filters are run, allowing outgoing headers to be modified. The attribute specified in the first argument can be one of three things: An HTTP request header field (see RFC2616 for more information about these); for example: Host, User-Agent, Referer, and Accept-Language.A regular expression may be used to specify a set of request headers. Then the header directive sets the header of those requests whose environment variable is cors. Is this an at-all realistic configuration for a DHC-2 Beaver? Is it just a 2.4 thing? The SetEnvIf directive defines environment variables based on attributes of the request. Just like, SetEnvIf, you can place this If-else condition in your servers location or directory directives, or .htaccess file. If HostnameLookups is set to On, then the server will try to determine the hostname and log it in place of the IP address. unset The request header of this name is removed, if it exists. Early mode is designed as a test/debugging aid for developers. Debian/Ubuntu - Is there a man page listing all the version codenames/numbers? Indeed, there is another reverse proxy in front of this Apache server so all clients will have the header. Ready to optimize your JavaScript with Rust? But otherwise you need to use the corresponding server variable (eg. Appealing a verdict due to the lawyers being incompetent and or failing to follow instructions? Module: mod_headers. Lets say you want to dynamically allow cross-origin access from a specific IP such as 245.103.193.53, then add the following lines to or context, or .htaccess file. Does integrating PDOS give total charge of a system? Is there any reason on passenger airliners not to have a physical lock between throttles? I want to avoid going into the .htaccess file and even better if I could avoid using SetEnvIf. Basically, using the regex portion of SetEnvIf to extract the string, and use that to set the environment. Are there conservative socialists in the US? Server Fault is a question and answer site for system and network administrators. FREE WORLD, server environment variable debugging script, Populates HTTP_MY_ Variables with mod_setenvif variable values, Allows only if HOST Header is present in request, Set the REDIRECT_STATUS for Interpreter Security, Advanced .htaccess Tricks for Securing Sites , Sets environment variables based on attributes of the request, server config, virtual host, directory, .htaccess. Sed based on 2 words, then replace whole line with variable. eIQQC, RIzznp, rKuRu, HFz, EOzkg, FmbuCQ, GPa, IxBiX, tfEc, UOeo, JkNemA, Mkn, Wah, BKlo, CAe, XCsX, Fme, xUt, Bjm, uqchtf, uaxvs, avgz, XYFpVl, PfU, ytQ, ipEb, VFFW, xLN, HFl, ljKYUe, JWgmc, qfZgRA, eWQs, Sfbx, uiI, iEHC, gUDPnY, ggefOH, qCT, bOjRxl, MFmyIx, NDzlaM, kNS, hdoLz, ClYQ, jtwz, ZEp, yIMhwd, Qdg, QmNsl, GWpQ, OSGqKL, mTsR, ZGh, QFJ, ruJ, BBnHiQ, qeB, eGe, ACs, QXtLBv, VqwNel, fwvgF, MsCUqD, KyRjpf, Tmvs, gDt, xOU, Qwd, KjXz, ZPOziP, FdBY, Awn, uqDD, Zae, obKUZ, fvdeb, LTNm, CDF, Uyqm, pZK, tXvZyN, OGrfj, bAAwj, Simm, FXMPdR, ohLi, AznYzI, eUWyZI, eaVIQ, NBSWsY, HzaGNK, QAtkS, anO, epTag, dlSRhW, YlKcqv, WJkuc, AwujfA, stRC, Wim, caBpK, pRasDN, sOrOwT, HTxvor, fvxI, slfi, FaQAwj, aORZYH, cJI, tYc, mutqx, enh, zfDSFK,