1 _ _ ____ _ 2 ___| | | | _ \| | 3 / __| | | | |_) | | 4 | (__| |_| | _ <| |___ 5 \___|\___/|_| \_\_____| 6 7 Things that could be nice to do in the future 8 9 Things to do in project cURL. Please tell us what you think, contribute and 10 send us patches that improve things! 11 12 All bugs documented in the KNOWN_BUGS document are subject for fixing! 13 14 1. libcurl 15 1.2 More data sharing 16 1.3 struct lifreq 17 1.4 signal-based resolver timeouts 18 1.5 get rid of PATH_MAX 19 1.6 Modified buffer size approach 20 1.7 Detect when called from within callbacks 21 1.8 Allow SSL (HTTPS) to proxy 22 23 2. libcurl - multi interface 24 2.1 More non-blocking 25 2.2 Fix HTTP Pipelining for PUT 26 27 3. Documentation 28 3.1 Update date and version in man pages 29 30 4. FTP 31 4.1 HOST 32 4.2 Alter passive/active on failure and retry 33 4.3 Earlier bad letter detection 34 4.4 REST for large files 35 4.5 ASCII support 36 37 5. HTTP 38 5.1 Better persistency for HTTP 1.0 39 5.2 support FF3 sqlite cookie files 40 5.3 Rearrange request header order 41 5.4 SPDY 42 5.5 auth= in URLs 43 44 6. TELNET 45 6.1 ditch stdin 46 6.2 ditch telnet-specific select 47 6.3 feature negotiation debug data 48 6.4 send data in chunks 49 50 7. SMTP 51 7.1 Pipelining 52 7.2 Enhanced capability support 53 54 8. POP3 55 8.1 Pipelining 56 8.2 Enhanced capability support 57 58 9. IMAP 59 9.1 Enhanced capability support 60 61 10. LDAP 62 10.1 SASL based authentication mechanisms 63 64 11. New protocols 65 11.1 RSYNC 66 67 12. SSL 68 12.1 Disable specific versions 69 12.2 Provide mutex locking API 70 12.3 Evaluate SSL patches 71 12.4 Cache OpenSSL contexts 72 12.5 Export session ids 73 12.6 Provide callback for cert verification 74 12.7 improve configure --with-ssl 75 12.8 Support DANE 76 77 13. GnuTLS 78 13.1 SSL engine stuff 79 13.2 check connection 80 81 14. SASL 82 14.1 Other authentication mechanisms 83 84 15. Client 85 15.1 sync 86 15.2 glob posts 87 15.3 prevent file overwriting 88 15.4 simultaneous parallel transfers 89 15.5 provide formpost headers 90 15.6 warning when setting an option 91 92 16. Build 93 16.1 roffit 94 95 17. Test suite 96 17.1 SSL tunnel 97 17.2 nicer lacking perl message 98 17.3 more protocols supported 99 17.4 more platforms supported 100 17.5 Add support for concurrent connections 101 102 18. Next SONAME bump 103 18.1 http-style HEAD output for FTP 104 18.2 combine error codes 105 18.3 extend CURLOPT_SOCKOPTFUNCTION prototype 106 107 19. Next major release 108 19.1 cleanup return codes 109 19.2 remove obsolete defines 110 19.3 size_t 111 19.4 remove several functions 112 19.5 remove CURLOPT_FAILONERROR 113 19.6 remove CURLOPT_DNS_USE_GLOBAL_CACHE 114 19.7 remove progress meter from libcurl 115 19.8 remove 'curl_httppost' from public 116 19.9 have form functions use CURL handle argument 117 19.10 Add CURLOPT_MAIL_CLIENT option 118 119============================================================================== 120 1211. libcurl 122 1231.2 More data sharing 124 125 curl_share_* functions already exist and work, and they can be extended to 126 share more. For example, enable sharing of the ares channel and the 127 connection cache. 128 1291.3 struct lifreq 130 131 Use 'struct lifreq' and SIOCGLIFADDR instead of 'struct ifreq' and 132 SIOCGIFADDR on newer Solaris versions as they claim the latter is obsolete. 133 To support ipv6 interface addresses for network interfaces properly. 134 1351.4 signal-based resolver timeouts 136 137 libcurl built without an asynchronous resolver library uses alarm() to time 138 out DNS lookups. When a timeout occurs, this causes libcurl to jump from the 139 signal handler back into the library with a sigsetjmp, which effectively 140 causes libcurl to continue running within the signal handler. This is 141 non-portable and could cause problems on some platforms. A discussion on the 142 problem is available at http://curl.haxx.se/mail/lib-2008-09/0197.html 143 144 Also, alarm() provides timeout resolution only to the nearest second. alarm 145 ought to be replaced by setitimer on systems that support it. 146 1471.5 get rid of PATH_MAX 148 149 Having code use and rely on PATH_MAX is not nice: 150 http://insanecoding.blogspot.com/2007/11/pathmax-simply-isnt.html 151 152 Currently the SSH based code uses it a bit, but to remove PATH_MAX from there 153 we need libssh2 to properly tell us when we pass in a too small buffer and 154 its current API (as of libssh2 1.2.7) doesn't. 155 1561.6 Modified buffer size approach 157 158 Current libcurl allocates a fixed 16K size buffer for download and an 159 additional 16K for upload. They are always unconditionally part of the easy 160 handle. If CRLF translations are requested, an additional 32K "scratch 161 buffer" is allocated. A total of 64K transfer buffers in the worst case. 162 163 First, while the handles are not actually in use these buffers could be freed 164 so that lingering handles just kept in queues or whatever waste less memory. 165 166 Secondly, SFTP is a protocol that needs to handle many ~30K blocks at once 167 since each need to be individually acked and therefore libssh2 must be 168 allowed to send (or receive) many separate ones in parallel to achieve high 169 transfer speeds. A current libcurl build with a 16K buffer makes that 170 impossible, but one with a 512K buffer will reach MUCH faster transfers. But 171 allocating 512K unconditionally for all buffers just in case they would like 172 to do fast SFTP transfers at some point is not a good solution either. 173 174 Dynamically allocate buffer size depending on protocol in use in combination 175 with freeing it after each individual transfer? Other suggestions? 176 1771.7 Detect when called from within callbacks 178 179 We should set a state variable before calling callbacks, so that we 180 subsequently can add code within libcurl that returns error if called within 181 callbacks for when that's not supported. 182 1831.8 Allow SSL (HTTPS) to proxy 184 185 To prevent local users from snooping on your traffic to the proxy. Supported 186 by Chrome already: 187 http://www.chromium.org/developers/design-documents/secure-web-proxy 188 189 ...and by Firefox soon: 190 https://bugzilla.mozilla.org/show_bug.cgi?id=378637 191 1922. libcurl - multi interface 193 1942.1 More non-blocking 195 196 Make sure we don't ever loop because of non-blocking sockets returning 197 EWOULDBLOCK or similar. Blocking cases include: 198 199 - Name resolves on non-windows unless c-ares is used 200 - NSS SSL connections 201 - HTTP proxy CONNECT operations 202 - SOCKS proxy handshakes 203 - file:// transfers 204 - TELNET transfers 205 - The "DONE" operation (post transfer protocol-specific actions) for the 206 protocols SFTP, SMTP, FTP. Fixing Curl_done() for this is a worthy task. 207 2082.2 Fix HTTP Pipelining for PUT 209 210 HTTP Pipelining can be a way to greatly enhance performance for multiple 211 serial requests and currently libcurl only supports that for HEAD and GET 212 requests but it should also be possible for PUT. 213 2143. Documentation 215 2163.1 Update date and version in man pages 217 218 'maketgz' or another suitable script could update the .TH sections of the man 219 pages at release time to use the current date and curl/libcurl version 220 number. 221 2224. FTP 223 2244.1 HOST 225 226 HOST is a command for a client to tell which host name to use, to offer FTP 227 servers named-based virtual hosting: 228 229 http://tools.ietf.org/html/rfc7151 230 2314.2 Alter passive/active on failure and retry 232 233 When trying to connect passively to a server which only supports active 234 connections, libcurl returns CURLE_FTP_WEIRD_PASV_REPLY and closes the 235 connection. There could be a way to fallback to an active connection (and 236 vice versa). http://curl.haxx.se/bug/feature.cgi?id=1754793 237 2384.3 Earlier bad letter detection 239 240 Make the detection of (bad) %0d and %0a codes in FTP URL parts earlier in the 241 process to avoid doing a resolve and connect in vain. 242 2434.4 REST for large files 244 245 REST fix for servers not behaving well on >2GB requests. This should fail if 246 the server doesn't set the pointer to the requested index. The tricky 247 (impossible?) part is to figure out if the server did the right thing or not. 248 2494.5 ASCII support 250 251 FTP ASCII transfers do not follow RFC959. They don't convert the data 252 accordingly. 253 2545. HTTP 255 2565.1 Better persistency for HTTP 1.0 257 258 "Better" support for persistent connections over HTTP 1.0 259 http://curl.haxx.se/bug/feature.cgi?id=1089001 260 2615.2 support FF3 sqlite cookie files 262 263 Firefox 3 is changing from its former format to a a sqlite database instead. 264 We should consider how (lib)curl can/should support this. 265 http://curl.haxx.se/bug/feature.cgi?id=1871388 266 2675.3 Rearrange request header order 268 269 Server implementors often make an effort to detect browser and to reject 270 clients it can detect to not match. One of the last details we cannot yet 271 control in libcurl's HTTP requests, which also can be exploited to detect 272 that libcurl is in fact used even when it tries to impersonate a browser, is 273 the order of the request headers. I propose that we introduce a new option in 274 which you give headers a value, and then when the HTTP request is built it 275 sorts the headers based on that number. We could then have internally created 276 headers use a default value so only headers that need to be moved have to be 277 specified. 278 2795.4 SPDY 280 281 Chrome and Firefox already support SPDY and lots of web services do. There's 282 a library for us to use for this (spdylay) that has a similar API and the 283 same author as nghttp2. 284 285 spdylay: https://github.com/tatsuhiro-t/spdylay 286 2875.5 auth= in URLs 288 289 Add the ability to specify the preferred authentication mechanism to use by 290 using ;auth=<mech> in the login part of the URL. 291 292 For example: 293 294 http://test:pass;auth=NTLM@example.com would be equivalent to specifying --user 295 test:pass;auth=NTLM or --user test:pass --ntlm from the command line. 296 297 Additionally this should be implemented for proxy base URLs as well. 298 2996. TELNET 300 3016.1 ditch stdin 302 303Reading input (to send to the remote server) on stdin is a crappy solution for 304library purposes. We need to invent a good way for the application to be able 305to provide the data to send. 306 3076.2 ditch telnet-specific select 308 309 Move the telnet support's network select() loop go away and merge the code 310 into the main transfer loop. Until this is done, the multi interface won't 311 work for telnet. 312 3136.3 feature negotiation debug data 314 315 Add telnet feature negotiation data to the debug callback as header data. 316 3176.4 send data in chunks 318 319 Currently, telnet sends data one byte at a time. This is fine for interactive 320 use, but inefficient for any other. Sent data should be sent in larger 321 chunks. 322 3237. SMTP 324 3257.1 Pipelining 326 327 Add support for pipelining emails. 328 3297.2 Enhanced capability support 330 331 Add the ability, for an application that uses libcurl, to obtain the list of 332 capabilities returned from the EHLO command. 333 3348. POP3 335 3368.1 Pipelining 337 338 Add support for pipelining commands. 339 3408.2 Enhanced capability support 341 342 Add the ability, for an application that uses libcurl, to obtain the list of 343 capabilities returned from the CAPA command. 344 3459. IMAP 346 3479.1 Enhanced capability support 348 349 Add the ability, for an application that uses libcurl, to obtain the list of 350 capabilities returned from the CAPABILITY command. 351 35210. LDAP 353 35410.1 SASL based authentication mechanisms 355 356 Currently the LDAP module only supports ldap_simple_bind_s() in order to bind 357 to an LDAP server. However, this function sends username and password details 358 using the simple authentication mechanism (as clear text). However, it should 359 be possible to use ldap_bind_s() instead specifying the security context 360 information ourselves. 361 36211. New protocols 363 36411.1 RSYNC 365 366 There's no RFC for the protocol or an URI/URL format. An implementation 367 should most probably use an existing rsync library, such as librsync. 368 36912. SSL 370 37112.1 Disable specific versions 372 373 Provide an option that allows for disabling specific SSL versions, such as 374 SSLv2 http://curl.haxx.se/bug/feature.cgi?id=1767276 375 37612.2 Provide mutex locking API 377 378 Provide a libcurl API for setting mutex callbacks in the underlying SSL 379 library, so that the same application code can use mutex-locking 380 independently of OpenSSL or GnutTLS being used. 381 38212.3 Evaluate SSL patches 383 384 Evaluate/apply Gertjan van Wingerde's SSL patches: 385 http://curl.haxx.se/mail/lib-2004-03/0087.html 386 38712.4 Cache OpenSSL contexts 388 389 "Look at SSL cafile - quick traces look to me like these are done on every 390 request as well, when they should only be necessary once per SSL context (or 391 once per handle)". The major improvement we can rather easily do is to make 392 sure we don't create and kill a new SSL "context" for every request, but 393 instead make one for every connection and re-use that SSL context in the same 394 style connections are re-used. It will make us use slightly more memory but 395 it will libcurl do less creations and deletions of SSL contexts. 396 39712.5 Export session ids 398 399 Add an interface to libcurl that enables "session IDs" to get 400 exported/imported. Cris Bailiff said: "OpenSSL has functions which can 401 serialise the current SSL state to a buffer of your choice, and recover/reset 402 the state from such a buffer at a later date - this is used by mod_ssl for 403 apache to implement and SSL session ID cache". 404 40512.6 Provide callback for cert verification 406 407 OpenSSL supports a callback for customised verification of the peer 408 certificate, but this doesn't seem to be exposed in the libcurl APIs. Could 409 it be? There's so much that could be done if it were! 410 41112.7 improve configure --with-ssl 412 413 make the configure --with-ssl option first check for OpenSSL, then GnuTLS, 414 then NSS... 415 41612.8 Support DANE 417 418 DNS-Based Authentication of Named Entities (DANE) is a way to provide SSL 419 keys and certs over DNS using DNSSEC as an alternative to the CA model. 420 http://www.rfc-editor.org/rfc/rfc6698.txt 421 422 An initial patch was posted by Suresh Krishnaswamy on March 7th 2013 423 (http://curl.haxx.se/mail/lib-2013-03/0075.html) but it was a too simple 424 approach. See Daniel's comments: 425 http://curl.haxx.se/mail/lib-2013-03/0103.html . libunbound may be the 426 correct library to base this development on. 427 42813. GnuTLS 429 43013.1 SSL engine stuff 431 432 Is this even possible? 433 43413.2 check connection 435 436 Add a way to check if the connection seems to be alive, to correspond to the 437 SSL_peak() way we use with OpenSSL. 438 43914. SASL 440 44114.1 Other authentication mechanisms 442 443 Add support for GSSAPI to SMTP, POP3 and IMAP. 444 44515. Client 446 44715.1 sync 448 449 "curl --sync http://example.com/feed[1-100].rss" or 450 "curl --sync http://example.net/{index,calendar,history}.html" 451 452 Downloads a range or set of URLs using the remote name, but only if the 453 remote file is newer than the local file. A Last-Modified HTTP date header 454 should also be used to set the mod date on the downloaded file. 455 45615.2 glob posts 457 458 Globbing support for -d and -F, as in 'curl -d "name=foo[0-9]" URL'. 459 This is easily scripted though. 460 46115.3 prevent file overwriting 462 463 Add an option that prevents cURL from overwriting existing local files. When 464 used, and there already is an existing file with the target file name 465 (either -O or -o), a number should be appended (and increased if already 466 existing). So that index.html becomes first index.html.1 and then 467 index.html.2 etc. 468 46915.4 simultaneous parallel transfers 470 471 The client could be told to use maximum N simultaneous parallel transfers and 472 then just make sure that happens. It should of course not make more than one 473 connection to the same remote host. This would require the client to use the 474 multi interface. http://curl.haxx.se/bug/feature.cgi?id=1558595 475 47615.5 provide formpost headers 477 478 Extending the capabilities of the multipart formposting. How about leaving 479 the ';type=foo' syntax as it is and adding an extra tag (headers) which 480 works like this: curl -F "coolfiles=@fil1.txt;headers=@fil1.hdr" where 481 fil1.hdr contains extra headers like 482 483 Content-Type: text/plain; charset=KOI8-R" 484 Content-Transfer-Encoding: base64 485 X-User-Comment: Please don't use browser specific HTML code 486 487 which should overwrite the program reasonable defaults (plain/text, 488 8bit...) 489 49015.6 warning when setting an option 491 492 Display a warning when libcurl returns an error when setting an option. 493 This can be useful to tell when support for a particular feature hasn't been 494 compiled into the library. 495 49616. Build 497 49816.1 roffit 499 500 Consider extending 'roffit' to produce decent ASCII output, and use that 501 instead of (g)nroff when building src/tool_hugehelp.c 502 50317. Test suite 504 50517.1 SSL tunnel 506 507 Make our own version of stunnel for simple port forwarding to enable HTTPS 508 and FTP-SSL tests without the stunnel dependency, and it could allow us to 509 provide test tools built with either OpenSSL or GnuTLS 510 51117.2 nicer lacking perl message 512 513 If perl wasn't found by the configure script, don't attempt to run the tests 514 but explain something nice why it doesn't. 515 51617.3 more protocols supported 517 518 Extend the test suite to include more protocols. The telnet could just do FTP 519 or http operations (for which we have test servers). 520 52117.4 more platforms supported 522 523 Make the test suite work on more platforms. OpenBSD and Mac OS. Remove 524 fork()s and it should become even more portable. 525 52617.5 Add support for concurrent connections 527 528 Tests 836, 882 and 938 were designed to verify that separate connections aren't 529 used when using different login credentials in protocols that shouldn't re-use 530 a connection under such circumstances. 531 532 Unfortunately, ftpserver.pl doesn't appear to support multiple concurrent 533 connections. The read while() loop seems to loop until it receives a disconnect 534 from the client, where it then enters the waiting for connections loop. When 535 the client opens a second connection to the server, the first connection hasn't 536 been dropped (unless it has been forced - which we shouldn't do in these tests) 537 and thus the wait for connections loop is never entered to receive the second 538 connection. 539 54018. Next SONAME bump 541 54218.1 http-style HEAD output for FTP 543 544 #undef CURL_FTP_HTTPSTYLE_HEAD in lib/ftp.c to remove the HTTP-style headers 545 from being output in NOBODY requests over FTP 546 54718.2 combine error codes 548 549 Combine some of the error codes to remove duplicates. The original 550 numbering should not be changed, and the old identifiers would be 551 macroed to the new ones in an CURL_NO_OLDIES section to help with 552 backward compatibility. 553 554 Candidates for removal and their replacements: 555 556 CURLE_FILE_COULDNT_READ_FILE => CURLE_REMOTE_FILE_NOT_FOUND 557 558 CURLE_FTP_COULDNT_RETR_FILE => CURLE_REMOTE_FILE_NOT_FOUND 559 560 CURLE_FTP_COULDNT_USE_REST => CURLE_RANGE_ERROR 561 562 CURLE_FUNCTION_NOT_FOUND => CURLE_FAILED_INIT 563 564 CURLE_LDAP_INVALID_URL => CURLE_URL_MALFORMAT 565 566 CURLE_TFTP_NOSUCHUSER => CURLE_TFTP_ILLEGAL 567 568 CURLE_TFTP_NOTFOUND => CURLE_REMOTE_FILE_NOT_FOUND 569 570 CURLE_TFTP_PERM => CURLE_REMOTE_ACCESS_DENIED 571 57218.3 extend CURLOPT_SOCKOPTFUNCTION prototype 573 574 The current prototype only provides 'purpose' that tells what the 575 connection/socket is for, but not any protocol or similar. It makes it hard 576 for applications to differentiate on TCP vs UDP and even HTTP vs FTP and 577 similar. 578 57919. Next major release 580 58119.1 cleanup return codes 582 583 curl_easy_cleanup() returns void, but curl_multi_cleanup() returns a 584 CURLMcode. These should be changed to be the same. 585 58619.2 remove obsolete defines 587 588 remove obsolete defines from curl/curl.h 589 59019.3 size_t 591 592 make several functions use size_t instead of int in their APIs 593 59419.4 remove several functions 595 596 remove the following functions from the public API: 597 598 curl_getenv 599 600 curl_mprintf (and variations) 601 602 curl_strequal 603 604 curl_strnequal 605 606 They will instead become curlx_ - alternatives. That makes the curl app 607 still capable of using them, by building with them from source. 608 609 These functions have no purpose anymore: 610 611 curl_multi_socket 612 613 curl_multi_socket_all 614 61519.5 remove CURLOPT_FAILONERROR 616 617 Remove support for CURLOPT_FAILONERROR, it has gotten too kludgy and weird 618 internally. Let the app judge success or not for itself. 619 62019.6 remove CURLOPT_DNS_USE_GLOBAL_CACHE 621 622 Remove support for a global DNS cache. Anything global is silly, and we 623 already offer the share interface for the same functionality but done 624 "right". 625 62619.7 remove progress meter from libcurl 627 628 The internally provided progress meter output doesn't belong in the library. 629 Basically no application wants it (apart from curl) but instead applications 630 can and should do their own progress meters using the progress callback. 631 632 The progress callback should then be bumped as well to get proper 64bit 633 variable types passed to it instead of doubles so that big files work 634 correctly. 635 63619.8 remove 'curl_httppost' from public 637 638 curl_formadd() was made to fill in a public struct, but the fact that the 639 struct is public is never really used by application for their own advantage 640 but instead often restricts how the form functions can or can't be modified. 641 642 Changing them to return a private handle will benefit the implementation and 643 allow us much greater freedoms while still maintaining a solid API and ABI. 644 64519.9 have form functions use CURL handle argument 646 647 curl_formadd() and curl_formget() both currently have no CURL handle 648 argument, but both can use a callback that is set in the easy handle, and 649 thus curl_formget() with callback cannot function without first having 650 curl_easy_perform() (or similar) called - which is hard to grasp and a design 651 mistake. 652 65319.10 Add CURLOPT_MAIL_CLIENT option 654 655 Rather than use the URL to specify the mail client string to present in the 656 HELO and EHLO commands, libcurl should support a new CURLOPT specifically for 657 specifying this data as the URL is non-standard and to be honest a bit of a 658 hack ;-) 659 660 Please see the following thread for more information: 661 http://curl.haxx.se/mail/lib-2012-05/0178.html 662 663