$Id: TODO,v 1.143 2016/02/13 11:18:15 fabiankeil Exp $ Some Privoxy-related tasks, sorted by the time they have been added, not by priority. The latest version should be available at: http://ijbswa.cvs.sourceforge.net/viewvc/ijbswa/current/TODO There's work in progress to fund development on these items using donations. If you want to donate, please have a look at: http://www.privoxy.org/faq/general.html#DONATE 1) Add more regression tests. Filters should be tested automatically (variables too). Could probably reuse large parts of Privoxy-Filter-Test. Note that there is currently work in progress to leverage curl's test suite, patches have been submitted upstream: http://curl.haxx.se/mail/lib-2014-06/0070.html 3) Fix some more XXX: comments. 6) Remove actions that aren't needed anymore: content-type-overwrite should probably stay as it's also used by some of the CGI pages (XXX: name them). crunch-client-header and crunch-server-header should probably go, their only advantage is that their search strings can be controlled through the CGI pages, other than that they only have disadvantages. crunch-if-none-match can be replaced with a header filter. prevent-compression has a misleading name and could be replaced with a header filter. 7) force-text-mode has a stupid name and should probably be renamed to force-filter-mode. 8) handle-as-empty-document and handle-as-image should be merged to something like handle-as{something} to prevent them from being activated at the same time. 10) There's a bug in the CGI editor that turns the first section's "Insert new section below" into a "Insert new section above" button. 11) CGI templates should use semantically-correct HTML and scale properly. Work in progress. 12) Support pipelining for outgoing connections. 14) Allow to filter POST parameters. 15) If trusted CGI pages are requested without trusted referrer, set the status code to 403 instead of 200. 16) Filter SSL encrypted content as well. At the beginning we could use a unencrypted connection between client and Privoxy, and use an encrypted connection between Privoxy and the server. This should be good enough for most of the content the user would want to filter. Interested donors: 2. 19) enable-forward-fallback. Syntax? Suggested by K.R. 21) User Manual delivery doesn't accept multiple slashes. Should it? 22) Verify action files properly (Including arguments) and act accordingly (should probably intercept all requests with a "Invalid option foo detected" CGI page). 23) Do the same in case of syntax errors in the configuration file, instead of just exiting or ignoring the problem. 25) Handle multiple filters with the same name better. Reject them? 26) Let show-url-info detect clearly invalid URLs. 27) Make errno logging less thread-unsafe. Verify that it's really an improvement. 28) Don't take default ports in case of invalid forwarding ports. 31) If a string action foo is disabled csp->action->string[ACTION_STRING_FOO] doesn't necessarily contain NULL, but may contain the string of an enabled foo action in an overruled section. Is it a bug? Does it matter? 32) In case of forwarding failures with socks port == 9050, show extra info about Tor (the whole FAQ entry?). 36) Unload unused action files directly, even if they are disabled without replacement. 38) In the final results, explicitly list disabled multi actions with their parameters. Not as trivial as it sounds. 40) When running in daemon mode, Privoxy's working directory is '/' which means it may not have permissions to dump core when necessary. Figure out a way to solve this. Introduce a cwd config option? 41) Change documentation framework to one that works cross-platform. Evaluate WML. 42) Add a DTrace USDT provider. Now that FreeBSD has userland DTrace support there's no longer any reason not to. 43) Write a tool to check URL patterns against URLs in the log file. This could be included in Privoxy-Regression-Test. 44) Privoxy-Log-Parser: Consider highlighting "Connection" in: 23:13:03.506 283b6100 Header: Replaced: 'Connection: Keep-Alive' with 'Connection: close' 50) Investigate possible PCRS template speedup when searching macros with strstr() before compiling pcrs commands. Investigated, needs some restructuring but is probably worth it. 51) Make user-manual directive more generic to allow serving the FAQ and files from user-specified directories. Consider changing the port for "same origin policy" issues. 53) Find a more reliable hoster. Involves finding out what our requirements are and which SF alternatives fulfil them. It would probably also make sense to look into what other projects did when migrating away from SF. 2014-05-13: Work in progress. Hosting wish list at the end of this file. Interested donors: 1. 54) Move away from CVS to a more modern revision control system. Find out if there are any objection against going with Git. Using Git would also have the advantage that SF now pretends to support it, so we could do it independently from 53). 58) Move more template strings from the code into the actual templates. 59) Import the German template translation. 60) Ask the Russian translators for input on how to make their life easier. 61) Consider (optionally?) skipping the hostname comparison when checking if a connections that goes to a HTTP proxy can be reused. Do all HTTP proxy support that? Is it worth it? 63) Reject clearly too large requests earlier? 64) Use proper copyright attribution. "Privoxy Developers" is no legal entity. 65) Polish Website. Probably involves ditching the Docbook mess in favour of wml. There are already several threads in the mailinglist archives about this. See also #41. 66) Stop hard-coding the number of action and filter files. 67) Clean up source code directory layout. Depends on 54 so we don't lose the revision history. 68) Use standard make syntax so we don't depend on GNU make. 69) Update autoconf setup (or move away from it). 70) If the server connection is reset but the headers are received, consider passing the mess to the client instead of showing the connect-failed template. Relates to #2698674. 74) Let Privoxy-Regression-Test optionally check that action sections which disable actions actually are preceded by sections that enable said actions. 75) Create a tool that creates Privoxy action (and filter?) files out of adblock files. Could be implemented as option for url-pattern-translator.pl. 76) Cache DNS responses. Note that this has been requested several times by users, but is not a developer priority. If you care about this, feel free to submit patches. 77) Allow to configure the IP address used in outgoing connections. 78) Allow to optionally use pcre's DFA algorithm. 79) Evaluate pcre alternatives. 80) Change FEATURE_EXTENDED_HOST_PATTERNS to support both extended and vanilla host patterns at the same time. Note that the requirement is to allow the user to decide if the domain pattern should be interpreted as regex or traditional host pattern and if it's not obvious that the user made any decision, default to the latter. Possible solutions would be: 1. An always-use-regex-domain-patterns config option 2. An enable-regex-domain-patterns-for-this-action-file option 3. An enable-regex-domain-patterns-for-this-action-file-until-the-user-says-otherwise option 4. A treat-the-domain-pattern-in-this-line-as-regex(-or-not) option 5. Combinations of the options above With 2+4, 3+4 or 2+3+4 being the preferences until further discussion. 82) Detect if the system time goes back in time let the user know if it caused any connections to get closed. 85) Once #84 is done, write a script that populates a directory with various common third-party icons (stumbleupon.png, facebook.png ...) and redirect requests for them to Privoxy. 86) Add a server-body-tagger action. This is trivial as as all the functionality required to do it already exists. 87) Add a client-body-tagger action. This is less trivial as we currently don't buffer client bodies. After 14) is implemented it would be trivial, though. 88) Investigate if there's a Perl module that Privoxy-Regression-Test could optionally use to keep connections alive, preferably while requiring less forks at the same time. 89) When multiple block actions apply, consider showing all the block reasons on the blocked page that haven't been overruled, not just the last one. 91) Add an optional limit for internal redirects. It would probably be reasonable to default to a limit of one and showing an error message if the request for the redirect URL would be redirected again. 92) The statistics currently aren't calculated correctly by Privoxy as each thread is only counted as one request which is no longer correct. This should be fixed, or the statistic code removed. Privoxy-Log-Parser's provides more detailed statistics, anyway. 93) Add a config directive to let Privoxy explicitly request either IPv4 (or IPv6) addresses, even if the system supports both. Could be useful as a workaround for misconfigured setups where the libc returns IPv6 addresses even if there's no IPv6 connectivity. 94) Add a config directive to let Privoxy prefer either IPv4 (or IPv6) addresses, instead of trusting the libc to return them in an order that makes sense. Like #93, this could be useful as a workaround for misconfigured setups. 95) Support a non-standard client header in CONNECT requests that contains the URL of the requested resource, which is then treated like the request URL. This way the client could opt-in for path-based blocking of https requests. Given that the headers from the CONNECT request aren't forwarded to the destination server, an unencrypted URL should be acceptable if the client and Privoxy are running on the same system or in a trusted environment. 96) Filters should be easier to look up. Currently get_filter() has to go through all filters and skip the filter types the caller isn't interested in. 98) When showing action section on the CGI pages, properly escape line breaks so they can be copy&pasted into action files without adjustments. 99) Figure out a mechanism through which a user can easily enable site-specific action sections that are too aggressive to be enabled by default. This could be similar to the presettings in default.action, but could also be just another action file that isn't used by default. 100) Create a cross-platform Privoxy control program and retire the win32 GUI. Integrate support for Privoxy-Regression-Test, Privoxy-Log-Parser, Privoxy-Filter-Test, uagen and similar tools. Interested donors: 1. 102) Add an include directive to split the config file into several parts. 103) Potential performance improvement for large action files: when figuring out which actions apply, check the action bit mask before pattern matching and skip section that wouldn't modify the actions already set. To increase the impact the sections would have to be applied in reverse. 104) The code to modify global_toggle_state should be factored out into a separate function. Currently we mess with it in three different files, but only in w32log.c the tray icon is explicitly set. The logging is inconsistent as well. For details see #3525694. 105) Add support for socks authentication. 106) actionlist.h should be embedded in a way that causes less text segment bloat. 107) Support more pcrs variables, for example $destination-ip-address and $source-ip-address. 108) Allow to use a somewhat random string instead of PRIVOXY-FORCE. 109) Let log_error() support the format specifier %S which should work like %s but escape new lines like %N. This would be useful to log the result of header filters which may inject new lines. 110) Add a global-buffer-limit directive that roughly limits how much malloc'ed memory Privoxy will use and can potentially be smaller than (buffer-limit * max-client-connections). 111) Reject requests if hosts and ports in request line and Host header don't match (before filters have been applied). 112) If a header filter is used to inject another header by inserting a \r\n (undocumented feature), detect it and split the headers so following header actions do not treat them as a single string. Alternatively add another header injection mechanism. 113) Log statistics upon receiving a certain signal (SIGINFO or SIGUSR1). 114) Properly deal with status code 100. The current "Continue hack" can cause problems for gpg when uploading keys through Privoxy. 115) Add ICAP (RFC 3507) support. FR #3615158. 116) Due to the use of sscanf(), Privoxy currently will fail to properly parse chunks whose size can't be represented with 32 bit. This is unlikely to cause problems in the real world, but should eventually be fixed anyway. See also: https://bugzilla.mozilla.org/show_bug.cgi?id=959100 118) There should be "escaped" dynamic variables that are guaranteed not to break filters. 119) Evaluate using pcre's jit mode. 120) Add an option to limit pcre's recursion limit below the default. On some platforms the recursion limit doesn't prevent pcre from running out of stack space, causing the kernel to kill Privoxy ungracefully. 121) Add HTTP/2 support. As a first step, incomming HTTP/1.x requests should be translated to outgoing HTTP/2 requests where possible (and if desired by the user). Interested donors: 1. 122) Allow customized log messages. 123) Evaluate if the voluntarily-disclose-session-keys option in Firefox (and other browsers) can be leveraged. Probably depends on #16. 124) Add support for the "lightweight OS capability and sandbox framework" Capsicum. http://www.cl.cam.ac.uk/research/security/capsicum/ Interested donors: 1. 125) Allow clients to HTTPS-encrypt the proxy connection. Interested donors: 1. 126) Run the Co-Advisor HTTP compliance tests, evaluate the results, fix the compliance issues that aren't by design and document the rest. Note that Privoxy developers qualify for free account upgrades: http://coad.measurement-factory.com/details.html#pricing 127) Add "real" CGI support (serve program output instead of forwarding the request). The work is mostly done due to +external-filter{}. 128) Add a config directive to control the stack limit. 129) Completely implement RFC 7230 4.1 (Chunked Transfer Coding). Currently Privoxy doesn't properly deal with trailers which are rarely used in the real world but should be supported anyway. 130) Move header_tagger() out of the parser structs and let it execute taggers one-by-one against all headers so the header order has less influence on the tagging result. As a bonus, dynamic taggers would have to be compiled less often. 131) The handle-as-empty-doc-returns-ok directive should be replaced with an action so the behaviour can be enabled on a per-request basis. Interested donors: 1. 133) Consider allowing bitcoin donations. Interested donors: 2. 134) Track the total number of bytes written to and received from a socket. 135) Add OpenBSM audit support. 136) Make builds reproducible. 137) Add a (preferably vector-based) logo. 138) Bring back the scripts to provide actions file feedback. Once upon a time (~2003) there were scripts on the webserver to make reporting action file feedback more convenient for the user and the actual reports more useful for the developers. They have been unusable for years and have thus been disabled, but making the reporting mechanism available again would be a good idea. 140) Toggling Privoxy off currently also disables stuff that probably shouldn't be affected (such as actions like forward-override). Investigate and fix or document. 141) Port Privoxy to CloudABI, which, despite the name, is actually rather neet. https://github.com/NuxiNL/cloudlibc 142) Remove or update the "internal" pcre version. 143) Add support for OpenBSD's pledge feature once it's stablelized. This should be a lot less work then #124. 144) Allow Privoxy admins to pre-define tags that are be set for clients that previously opted-in through the CGI interface. This would be useful in multi-user setups where admins may want to allow users to disable certain actions and filters for themselves without affecting others. Even in single-user setups this could be useful to allow more fine-grained toggling. For example to disable request blocking while still crunching cookies, or to disable experimental filters only. Interested donors: 1. 145) Once #144 is implemented, allow clients to opt-in to the tagging for a limited amount of time (or number of requests). Interested donors: 1. 146) Once #144 is implemented, optionally allow to save the opt-in status to disk. 147) Improve "Building from Source" section in the user manual. A common problem seems to be that it's not obvious to non-technical users how the listed dependencies can be installed on the commonly used platforms. Adding a couple of examples should also be useful for technical users (like Privoxy developers) who want to install or test Privoxy on platforms they are not familiar with. 146) Once #145 is implemented, allow clients to specify the time. ########################################################################## Hosting wish list (relevant for #53) What we need: - Bug tracker - Mailinglists (Mailman with public archives preferred) - Webspace (on a Unix-like OS that works with the webserver targets in GNUMakefile) - Source code repositories (currently CVS, but migrating away from it is TODO #54 anyway and shouldn't be too much trouble) - Commit mails (preferably with unified diffs) (Unsorted) details to look at when evaluating hosters: 1. Preferably no third-party ads and trackers. External images, CSS and JavaScript may count as trackers but texts like "supported by company XYZ" may be acceptable. 2. JavaScript should be optional or not used at all. 3. Services we don't need shouldn't be enabled anyway. (We currently don't use Web forums, wikis, surveys etc.) 4. It would be preferable if the hoster didn't have a bad track record as far as user experience, security and privacy are concerned and if the terms of service are "reasonable" and haven't changed too often in the past. Updates in the past should have been improvements and not regressions. 5. It would be preferable if most of the server administration is done by a trusted third-party (or at least not a lot of work for us). 6. The server(s) should be located in a country with laws we can understand and follow (or at least not unintentionally violate). 7. A server location in a country with some kind of due process and strong data protection laws (at least on paper) would be preferable. 8. Given that Privoxy is a free software project it would be preferable if the hoster would use free software where possible. 9. Migrating away from the hoster in the future without losing any important data should be possible without writing web scrapers first.