1 Changelog for the c-ares project
3 Version 1.7.4 (December 9, 2010)
7 o local-bind: Support binding to local interface/IPs, see
8 ares_set_local_ip4, ares_set_local_ip6, ares_set_local_dev
12 o memory leak in ares_getnameinfo
13 o add missing break that caused get_ares_servers to fail
14 o ares_parse_a_reply: fix CNAME response parsing
15 o init_by_options: don't copy an empty sortlist
16 o Replaced uint32_t with unsigned int to fix broken builds
17 on a couple of platforms
18 o Fix lookup with HOSTALIASES set
19 o adig: fix NAPTR parsing
20 o compiler warning cleanups
22 Version 1.7.3 (June 11, 2010)
27 o now includes all files necessary to build it (1.7.2 lacked a file)
29 Version 1.7.2 (June 10, 2010)
33 o Added ares_parse_mx_reply()
37 o ares_init: Last, not first instance of domain or search should win
38 o improve alternative definition of bool
39 o fix VS2010 compiler warnings
42 Version 1.7.1 (Mar 23, 2010)
44 * May 31, 2010 (Jakub Hrozek)
45 - Use the last instance of domain/search, not the first one
47 * March 23, 2010 (Daniel Stenberg)
48 - We switched from CVS to git. See http://github.com/bagder/c-ares
50 * March 5, 2010 (Daniel Stenberg)
51 - Daniel Johnson provided fixes for building with the clang compiler.
53 * March 5, 2010 (Yang Tse)
54 - Added IPv6 name servers support. Implementation has been based on code,
55 comments and feedback provided November and December of 2008 by Daniel
56 Stenberg, Gregor Jasny, Phil Blundell and myself, December 2009 by Cedric
57 Bail, and February 2010 by Jakub Hrozek on the c-ares mailing list. On
58 March I reviewed all that, selected the best of each, and adjusted or
59 extended parts of it to make the best fit.
61 The external and visible result of all this is that two new functions are
62 added to the external API, ares_get_servers() and ares_set_servers(), which
63 becomes now the preferred way of getting and setting name servers for any
64 ares channel as these support both IPv4 and IPv6 name servers.
66 In order to not break ABI compatibility, ares_init_options() with option
67 mask ARES_OPT_SERVERS and ares_save_options() may still be used in code
68 which is intended to run on IPv4-only stacks. But remember that these
69 functions do not support IPv6 name servers. This implies that if the user
70 is capable of defining or providing an IPv6 name server, and the app is
71 using ares_init_options() or ares_save_options() at some point to handle
72 the name servers, the app will likely lose IPv6 name servers.
74 * January 28, 2010 (Daniel Stenberg)
75 - Tommie Gannert pointed out a silly bug in ares_process_fd() since it didn't
76 check for broken connections like ares_process() did. Based on that, I
77 merged the two functions into a single generic one with two front-ends.
79 * December 29, 2009 (Yang Tse)
80 - Laszlo Tamas Szabo adjusted Makefile.msvc compiler options so that where
81 run-time error checks enabling compiler option /GZ was used it is replaced
82 with equivalent /RTCsu for Visual Studio 2003 and newer versions. Option
83 /GX is replaced with equivalent /EHsc for all versions. Also fixed socket
84 data type for internal configure_socket function.
86 * December 21, 2009 (Yang Tse)
87 - Ingmar Runge noticed that Windows config-win32.h configuration file
88 did not include a definition for HAVE_CLOSESOCKET which resulted in
89 function close() being inappropriately used to close sockets.
91 Version 1.7.0 (Nov 30, 2009)
93 * November 26, 2009 (Yang Tse)
94 - Larry Lansing fixed ares_parse_srv_reply to properly parse replies
95 which might contain non-SRV answers, skipping over potential non-SRV
98 * November 23, 2009 (Yang Tse)
99 - Changed naming convention for c-ares libraries built with MSVC, details
100 and build instructions provided in README.msvc file.
102 * November 22, 2009 (Yang Tse)
103 - Jakub Hrozek fixed more function prototypes in man pages to sync them
104 with the ones declared in ares.h
106 - Jakub Hrozek renamed addrttl and addr6ttl structs to ares_addrttl and
107 ares_addr6ttl in order to prevent name space pollution, along with
108 necessary changes to code base and man pages.This change does not break
109 ABI, there is no need to recompile existing applications. But existing
110 applications using these structs with the old name will need source code
111 adjustments when recompiled using c-ares 1.7.0.
113 * November 21, 2009 (Yang Tse)
114 - Added manifest stuff to Makefile.msvc.
116 * November 20, 2009 (Yang Tse)
117 - Fixed several function prototypes in man pages that were out of sync
118 with the ones declared in ares.h. Added ares_free_data() along with
119 man page. Updated ares_parse_srv_reply() and ares_parse_txt_reply()
120 with changes from Jakub Hrozek making these now return linked lists
121 instead of arrays, and merging the ares_free_data() adjustments.
123 * November 10, 2009 (Yang Tse)
124 - Updated MSVC 6.0 project files to match settings from Makefile.msvc.
126 * November 9, 2009 (Yang Tse)
127 - Makefile.msvc is now the reference method to build c-ares and sample
128 programs with any MSVC compiler or MS Visual Studio version. If no
129 option or target are specified it builds dynamic and static c-ares
130 libraries in debug and release flavours and also builds all sample
131 programs using each of the different c-ares libraries.
133 * November 2, 2009 (Yang Tse)
134 - Renamed c-ares setup.h to ares_setup.h
136 * October 31, 2009 (Yang Tse)
137 - Symbol hiding configure options are named now --enable-symbol-hiding
138 and --disable-symbol-hiding in an attempt to make them less ambiguous.
140 * October 30, 2009 (Yang Tse)
141 - Many fixes for ares_parse_txt_reply()
143 * October 29, 2009 (Daniel Stenberg)
144 - Jakub Hrozek added ares_parse_txt_reply() for TXT parsing
146 * October 29, 2009 (Yang Tse)
147 - Updated MSVC 6.0 workspace and project files that allows building
148 dynamic and static c-ares libraries in debug and release flavours.
149 Additionally each of the three sample programs is built against
150 each of the four possible c-ares libraries, generating all this
151 a total number of 12 executables and 4 libraries.
153 * October 28, 2009 (Yang Tse)
154 - Initial step towards the ability to reduce c-ares exported symbols
155 when built as a shared library based on the 'visibility' attribute
156 for GNUC and Intel compilers and based on __global for Sun compilers,
157 taking also in account __declspec function decoration for Win32 and
160 * October 27, 2009 (Yang Tse)
161 - Fixed Pelles C Win32 target compilation issues.
163 * October 23, 2009 (Yang Tse)
164 - John Engelhart noticed an unreleased problem relative to a duplicate
165 ARES_ECANCELLED error code value and missing error code description.
167 * October 7, 2009 (Yang Tse)
168 - Overhauled ares__get_hostent() Fixing out of bounds memory overwrite
169 triggered with malformed /etc/hosts file. Improving parsing of /etc/hosts
170 file. Validating requested address family. Ensuring that failures always
171 return a NULL pointer. Adjusting header inclusions.
173 * October 6, 2009 (Yang Tse)
174 - Fix ssize_t redefinition errors on WIN64 reported by Alexey Simak.
176 * September 29, 2009 (Yang Tse)
177 - Make configure script also check if _REENTRANT definition is required to
178 make errno available as a preprocessor macro.
180 * September 7, 2009 (Yang Tse)
181 - Add T_SRV portability check to ares_parse_srv_reply.c
183 * 4 Sep 2009 (Daniel Stenberg)
184 - Jakub Hrozek added ares_parse_srv_reply() for SRV parsing
186 * 3 Aug 2009 (Daniel Stenberg)
187 - Joshua Kwan fixed the init routine to fill in the defaults for stuff that
188 fails to get inited by other means. This fixes a case of when the c-ares
189 init fails when internet access is fone.
191 - Timo Teras changed the reason code used in the resolve callback done when
192 ares_cancel() is used, to be ARES_ECANCELLED instead of ARES_ETIMEOUT to
193 better allow the callback to know what's happening.
195 * 14 Jul 2009 (Guenter Knauf)
196 - renamed generated config.h to ares_config.h to avoid any future clashes
197 with config.h from other projects.
199 * June 20 2009 (Yang Tse)
200 - Refactor how libraries are checked for connect() function in configure
201 script and check for connect() as it is done for other functions.
203 * June 19 2009 (Yang Tse)
204 - Make sclose() function-like macro definition used to close a socket,
205 now solely based on HAVE_CLOSESOCKET and HAVE_CLOSESOCKET_CAMEL
206 config file preprocessor definitions
208 * June 18 2009 (Yang Tse)
209 - Add CloseSocket camel case function check for configure script.
211 * June 17 2009 (Yang Tse)
212 - Check for socket() and closesocket() as it is done for other functions
215 * June 11 2009 (Yang Tse)
216 - Modified buildconf so that when automake runs it copies missing files
217 instead of symlinking them.
219 * June 8 2009 (Yang Tse)
220 - Removed buildconf.bat from release and daily snapshot archives. This
221 file is only for CVS tree checkout builds.
223 * May 26 2009 (Yang Tse)
224 - Added --enable-curldebug configure option to enable and disable building
225 with the low-level curl debug memory tracking 'feature' to allow decoupled
226 setting from --enable-debug, allowing again to build c-ares independently
229 For the c-ares library option --enable-debug enables debug build features
230 which are _not_ related with memory tracking. For the c-ares library when
231 --enable-debug is given it does not enable the memory tracking feature. If
232 you wish to enable the curl debug memory tracking you must use configure
233 option --enable-curldebug explicitily to do so.
235 Internally, definition of preprocessor symbol DEBUGBUILD restricts code
236 which is only compiled for debug enabled builds. And symbol CURLDEBUG is
237 used to differentiate code which is _only_ used for memory tracking.
239 Make ares_init(), ares_dup() and ares_init_options() fail returning
240 ARES_ENOTINITIALIZED if library initialization has not been performed
241 calling ares_library_init().
243 * May 20 2009 (Yang Tse)
244 - Added ares_library_init() and ares_library_cleanup() man pages.
246 * May 19 2009 (Yang Tse)
247 - Introduced ares_library_init() and ares_library_cleanup() functions.
249 This is an API and ABI break for Win32/64 systems. Non-Win32/64 build targets
250 using c-ares 1.7.0 can still survive without calling these functions. Read all
251 the details on ares_library_init(3) and ares_library_cleanup(3) man pages that
254 curl/libcurl 7.19.5 is fully compatible with c-ares 1.7.0 on all systems.
256 In order to use c-ares 1.7.0 with curl/libcurl on Win32/64 systems it is
257 required that curl/libcurl is 7.19.5 or newer. In other words, it is not
258 possible on Win32/64 to use c-ares 1.7.0 with a curl/libcurl version less
261 * May 11 2009 (Daniel Stenberg)
262 - Gregor Jasny made c-ares link with libtool 's -export-symbols-regex option to
263 only expose functions starting with ares_.
265 * May 7 2009 (Yang Tse)
266 - Fix an m4 overquoting triggering a spurious 'AS_TR_CPP' symbol definition
267 attempt in generated config.h
269 * May 2 2009 (Yang Tse)
270 - Use a build-time configured ares_socklen_t data type instead of socklen_t.
272 * April 21 2009 (Yang Tse)
273 - Moved potential inclusion of system's malloc.h and memory.h header files to
274 setup_once.h. Inclusion of each header file is based on the definition of
275 NEED_MALLOC_H and NEED_MEMORY_H respectively.
277 * March 11 2009 (Yang Tse)
278 - Japheth Cleaver fixed acountry.c replacing u_long with unsigned long.
280 * February 20 2009 (Yang Tse)
281 - Do not halt compilation when using VS2008 to build a Windows 2000 target.
283 * February 3 2009 (Phil Blundell)
284 - If the server returns garbage or nothing at all in response to an AAAA query,
285 go on and ask for A records anyway.
287 * January 31 2009 (Daniel Stenberg)
288 - ares_gethostbyname() now accepts 'AF_UNSPEC' as a family for resolving
289 either AF_INET6 or AF_INET. It works by accepting any of the looksups in the
290 hosts file, and it resolves the AAAA field with a fallback to A.
292 * January 14 2009 (Daniel Stenberg)
293 - ares.h no longer uses the HAVE_STRUCT_IN6_ADDR define check, but instead it
294 now declares the private struct ares_in6_addr for all systems instead of
295 relying on one possibly not present in the system.
297 * January 13 2009 (Phil Blundell)
298 - ares__send_query() now varies the retry timeout pseudo-randomly to avoid
299 packet storms when several queries were started at the same time.
301 * January 11 2009 (Daniel Stenberg)
302 - Phil Blundell added the internal function ares__expand_name_for_response()
303 that is now used by the ares_parse_*_reply() functions instead of the
304 ares_expand_name() simply to easier return ARES_EBADRESP for the cases where
305 the name expansion fails as in responses that really isn't expected.
307 Version 1.6.0 (Dec 9, 2008)
309 * December 9 2008 (Gisle Vanem)
311 Fixes for Win32 targets using the Watt-32 tcp/ip stack.
313 * Dec 4 2008 (Daniel Stenberg)
315 Gregor Jasny provided the patch that introduces ares_set_socket_callback(),
316 and I edited it to also get duped by ares_dup().
318 * Dec 3 2008 (Daniel Stenberg)
322 I made sure the public ares_config struct looks like before and yet it
323 supports the ROTATE option thanks to c-ares now storing the "optmask"
324 internally. Thus we should be ABI compatible with the past release(s)
325 now. My efforts mentioned below should not break backwards ABI compliance.
327 Here's how I suggest we proceed with the API:
329 ares_init() will be primary "channel creator" function.
331 ares_init_options() will continue to work exactly like now and before. For
332 starters, it will be the (only) way to set the existing options.
334 ares_save_options() will continue to work like today, but will ONLY save
335 options that you can set today (including ARES_OPT_ROTATE actually) but new
336 options that we add may not be saved with this.
338 Instead we introduce:
340 ares_dup() that instead can make a new channel and clone the config used
341 from an existing channel. It will then clone all config options, including
342 future new things we add.
344 ares_set_*() style functions that set (new) config options. As a start we
345 simply add these for new functionality, but over time we can also introduce
346 them for existing "struct ares_options" so that we can eventually deprecate
347 the two ares_*_options() functions.
349 ares_get_*() style functions for extracting info from a channel handle that
350 should be used instead of ares_save_options().
352 * Nov 26 2008 (Yang Tse)
353 - Brad Spencer provided changes to allow buildconf to work on OS X.
355 - Gerald Combs fixed a bug in ares_parse_ptr_reply() which would cause a
356 buffer to shrink instead of expand if a reply contained 8 or more records.
358 * Nov 25 2008 (Yang Tse)
359 - In preparation for the upcomming IPv6 nameservers patch, the internal
360 ares_addr union is now changed into an internal struct which also holds
363 * Nov 19 2008 (Daniel Stenberg)
364 - Brad Spencer brought the new function ares_gethostbyname_file() which simply
365 resolves a host name from the given file, using the regular hosts syntax.
367 * Nov 1 2008 (Daniel Stenberg)
368 - Carlo Contavalli added support for the glibc "rotate" option, as documented
371 causes round robin selection of nameservers from among those listed. This
372 has the effect of spreading the query load among all listed servers, rather
373 than having all clients try the first listed server first every time.
375 You can enable it with ARES_OPT_ROTATE
377 * Oct 21 2008 (Yang Tse)
378 Charles Hardin added handling of EINPROGRESS for UDP connects.
380 * Oct 18 2008 (Daniel Stenberg)
381 Charles Hardin made adig support a regular numerical dotted IP address for the
384 * Oct 7 2008 (Yang Tse)
385 - Added --enable-optimize configure option to enable and disable compiler
386 optimizations to allow decoupled setting from --enable-debug.
388 * Oct 2 2008 (Yang Tse)
389 - Added --enable-warnings configure option to enable and disable strict
390 compiler warnings to allow decoupled setting from --enable-debug.
392 * Sep 17 2008 (Yang Tse)
393 - Code reorganization to allow internal/private use of "nameser.h" to any
394 system that lacks arpa/nameser.h or arpa/nameser_compat.h header files.
396 * Sep 16 2008 (Yang Tse)
397 - Code reorganization to allow internal/private use of ares_writev to any
398 system that lacks the writev function.
400 * Sep 15 2008 (Yang Tse)
401 - Code reorganization to allow internal/private use of ares_strcasecmp to any
402 system that lacks the strcasecmp function.
404 - Improve configure detection of some string functions.
406 * Sep 11 2008 (Yang Tse)
407 - Code reorganization to allow internal/private use of ares_strdup to any
408 system that lacks the strdup function.
410 Version 1.5.3 (Aug 29, 2008)
412 * Aug 25 2008 (Yang Tse)
413 - Improvement by Brad House:
415 This patch addresses an issue in which a response could be sent back to the
416 source port of a client from a different address than the request was made to.
417 This is one form of a DNS cache poisoning attack.
419 The patch simply uses recvfrom() rather than recv() and validates that the
420 address returned from recvfrom() matches the address of the server we have
421 connected to. Only necessary on UDP sockets as they are connection-less, TCP
424 - Fix by George Neill:
425 Fixed compilation of acountry sample application failure on some systems.
427 * Aug 4 2008 (Daniel Stenberg)
428 - Fix by Tofu Linden:
431 * Users (usually, but not always) on 2-Wire routers and the Comcast service
432 and a wired connection to their router would find that the second and
433 subsequent DNS lookups from fresh processes using c-ares to resolve the same
434 address would cause the process to never see a reply (it keeps polling for
435 around 1m15s before giving up).
438 * On such a machine (and yeah, it took us a lot of QA to find the systems
439 that reproduce such a specific problem!), do 'ahost www.secondlife.com',
440 then do it again. The first process's lookup will work, subsequent lookups
441 will time-out and fail.
444 * init_id_key() was calling randomize_key() *before* it initialized
445 key->state, meaning that the randomness generated by randomize_key() is
446 immediately overwritten with deterministic values. (/dev/urandom was also
447 being read incorrectly in the c-ares version we were using, but this was
448 fixed in a later version.)
449 * This makes the stream of generated query-IDs from any new c-ares process
450 be an identical and predictable sequence of IDs.
451 * This makes the 2-Wire's default built-in DNS server detect these queries
452 as probable-duplicates and (erroneously) not respond at all.
455 * Aug 4 2008 (Yang Tse)
456 - Autoconf 2.62 has changed the behaviour of the AC_AIX macro which we use.
457 Prior versions of autoconf defined _ALL_SOURCE if _AIX was defined. 2.62
458 version of AC_AIX defines _ALL_SOURCE and other four preprocessor symbols
459 no matter if the system is AIX or not. To keep the traditional behaviour,
460 and an uniform one across autoconf versions AC_AIX is replaced with our
461 own internal macro CARES_CHECK_AIX_ALL_SOURCE.
463 * Aug 1 2008 (Yang Tse)
464 - Configure process now checks if the preprocessor _REENTRANT symbol is already
465 defined. If it isn't currently defined a set of checks are performed to test
466 if its definition is required to make visible to the compiler a set of *_r
467 functions. Finally, if _REENTRANT is already defined or needed it takes care
468 of making adjustments necessary to ensure that it is defined equally for the
469 configure process tests and generated config file.
471 * Jul 20 2008 (Yang Tse)
472 - When recvfrom prototype uses a void pointer for arguments 2, 5 or 6 this will
473 now cause the definition, as appropriate, of RECVFROM_TYPE_ARG2_IS_VOID,
474 RECVFROM_TYPE_ARG5_IS_VOID or RECVFROM_TYPE_ARG6_IS_VOID.
476 * Jul 17 2008 (Yang Tse)
477 - RECVFROM_TYPE_ARG2, RECVFROM_TYPE_ARG5 and RECVFROM_TYPE_ARG6 are now defined
478 to the data type pointed by its respective argument and not the pointer type.
480 * Jul 16 2008 (Yang Tse)
481 - Improved configure detection of number of arguments for getservbyport_r.
482 Detection is now based on compilation checks instead of linker ones.
484 - Configure process now checks availability of recvfrom() socket function and
485 finds out its return type and the types of its arguments. Added definitions
486 for non-configure systems config files, and introduced macro sreadfrom which
487 will be used on udp sockets as a recvfrom() wrapper in the future.
489 * Jul 15 2008 (Yang Tse)
490 - Introduce definition of _REENTRANT symbol in setup.h to improve library
491 usability. Previously the configure process only used the AC_SYS_LARGEFILE
492 macro for debug builds, now it is also used for non-debug ones enabling the
493 use of configure options --enable-largefile and --disable-largefile which
494 might be needed for library compatibility. Remove checking the size of
495 curl_off_t, it is no longer needed.
497 * Jul 3 2008 (Daniel Stenberg)
498 - Phil Blundell: If you ask ares_gethostbyname() to do an AF_INET6 lookup and
499 the target host has only A records, it automatically falls back to an
500 AF_INET lookup and gives you the A results. However, if the target host has
501 a CNAME record, this behaviour is defeated since the original query does
502 return some data even though ares_parse_aaa_reply() doesn't consider it
503 relevant. Here's a small patch to make it behave the same with and without
506 * Jul 2 2008 (Yang Tse)
507 - Fallback to gettimeofday when monotonic clock is unavailable at run-time.
509 * Jun 30 2008 (Daniel Stenberg)
511 - As was pointed out to me by Andreas Schuldei, the MAXHOSTNAMELEN define is
512 not posix or anything and thus c-ares failed to build on hurd (and possibly
513 elsewhere). The define was also somewhat artificially used in the windows
514 port. Now, I instead rewrote the use of gethostbyname to enlarge the host
515 name buffer in case of need and totally avoid the use of the MAXHOSTNAMELEN
516 define. I thus also removed the defien from the namser.h file where it was
517 once added for the windows build.
519 I also fixed init_by_defaults() function to not leak memory in case if
522 * Jun 9 2008 (Yang Tse)
524 - Make libcares.pc generated file for pkg-config include information relative
525 to the libraries needed for the static linking of c-ares.
527 * May 30 2008 (Yang Tse)
529 - Brad House fixed a missing header file inclusion in adig sample program.
531 Version 1.5.2 (May 29, 2008)
533 * May 13 2008 (Daniel Stenberg)
535 - Introducing millisecond resolution support for the timeout option. See
536 ares_init_options()'s ARES_OPT_TIMEOUTMS.
538 * May 9 2008 (Yang Tse)
540 - Use monotonic time source if available, for private function ares__tvnow()
542 * May 7 2008 (Daniel Stenberg)
544 - Sebastian made c-ares able to return all PTR-records when doing reverse
545 lookups. It is not common practice to have multiple PTR-Records for a single
546 IP, but its perfectly legal and some sites have those.
548 - Doug Goldstein provided a configure patch: updates autoconf 2.13 usage to
549 autoconf 2.57 usage (which is the version you have specified as the minimum
550 version). It's a minor change but it does clean up some warnings with newer
551 autoconf (specifically 2.62).
553 * May 5 2008 (Yang Tse)
555 - Improved parsing of resolver configuration files.
557 * April 4 2008 (Daniel Stenberg)
559 - Eino Tuominen improved the code when a file is used to seed the randomizer.
561 - Alexey Simak made adig support NAPTR records
563 - Alexey Simak fixed the VC dsp file by adding the missing source file
566 * December 11 2007 (Gisle Vanem)
568 - Added another sample application; acountry.c which converts an
569 IPv4-address(es) and/or host-name(s) to country-name and country-code.
570 This uses the service of the DNSBL at countries.nerd.dk.
572 * December 3 2007 (Daniel Stenberg)
574 - Brad Spencer fixed the configure script to assume that there's no
575 /dev/urandom when built cross-compiled as then the script cannot check for
578 - Erik Kline cleaned up ares_gethostbyaddr.c:next_lookup() somewhat
580 Version 1.5.1 (Nov 21, 2007)
582 * November 21 2007 (Daniel Stenberg)
584 - Robin Cornelius pointed out that ares_llist.h was missing in the release
587 Version 1.5.0 (Nov 21, 2007)
589 * October 2 2007 (Daniel Stenberg)
591 - ares_strerror() segfaulted if the input error number was out of the currently
594 - Yang Tse: Avoid a segfault when generating a DNS "Transaction ID" in
595 internal function init_id_key() under low memory conditions.
597 * September 28 2007 (Daniel Stenberg)
599 - Bumped version to 1.5.0 for next release and soname bumped to 2 due to ABI
600 and API changes in the progress callback (and possibly more coming up from
603 * September 28 2007 (Steinar H. Gunderson)
605 - Don't skip a server if it's the only one. (Bugfix from the Google tree.)
607 - Made the query callbacks receive the number of timeouts that happened during
608 the execution of a query, and updated documentation accordingly. (Patch from
611 - Support a few more socket options: ARES_OPT_SOCK_SNDBUF and
614 - Always register for TCP events even if there are no outstanding queries, as
615 the other side could always close the connection, which is a valid event
616 which should be responded to.
618 * September 22 2007 (Daniel Stenberg)
620 - Steinar H. Gunderson fixed: Correctly clear sockets from the fd_set on in
621 several functions (write_tcp_data, read_tcp_data, read_udp_packets) so that
622 if it fails and the socket is closed the following code doesn't try to use
625 - Steinar H. Gunderson modified c-ares to now also do to DNS retries even when
626 TCP is used since there are several edge cases where it still makes sense.
628 - Brad House provided a fix for ares_save_options():
630 Apparently I overlooked something with the ares_save_options() where it
631 would try to do a malloc(0) when no options of that type needed to be saved.
632 On most platforms, this was fine because malloc(0) doesn't actually return
633 NULL, but on AIX it does, so ares_save_options would return ARES_ENOMEM.
635 * July 14 2007 (Daniel Stenberg)
637 - Vlad Dinulescu fixed two outstanding valgrind reports:
639 1. In ares_query.c , in find_query_by_id we compare q->qid (which is a short
640 int variable) with qid, which is declared as an int variable. Moreover,
641 DNS_HEADER_SET_QID is used to set the value of qid, but DNS_HEADER_SET_QID
642 sets only the first two bytes of qid. I think that qid should be declared as
643 "unsigned short" in this function.
645 2. The same problem occurs in ares_process.c, process_answer() . query->qid
646 (an unsigned short integer variable) is compared with id, which is an
647 integer variable. Moreover, id is initialized from DNS_HEADER_QID which sets
648 only the first two bytes of id. I think that the id variable should be
649 declared as "unsigned short" in this function.
651 Even after declaring these variables as "unsigned short", the valgrind
652 errors are still there. Which brings us to the third problem.
654 3. The third problem is that Valgrind assumes that query->qid is not
655 initialised correctly. And it does that because query->qid is set from
656 DNS_HEADER_QID(qbuf); Valgrind says that qbuf has unitialised bytes. And
657 qbuf has uninitialised bytes because of channel->next_id . And next_id is
658 set by ares_init.c:ares__generate_new_id() . I found that putting short r=0
659 in this function (instead of short r) makes all Valgrind warnings go away.
660 I have studied ares__rc4() too, and this is the offending line:
662 buffer_ptr[counter] ^= state[xorIndex]; (ares_query.c:62)
664 This is what triggers Valgrind.. buffer_ptr is unitialised in this function,
665 and by applying ^= on it, it remains unitialised.
667 Version 1.4.0 (June 8, 2007)
669 * June 4 2007 (Daniel Stenberg)
671 - James Bursa reported a major memory problem when resolving multi-IP names
672 and I found and fixed the problem. It was added by Ashish Sharma's patch
675 When I then tried to verify multiple entries in /etc/hosts after my fix, I
676 got another segfault and decided this code was not ripe for inclusion and I
681 - Brad Spencer found and fixed three flaws in the code, found with the new
682 gcc 4.2.0 warning: -Waddress
684 - Brad House fixed VS2005 compiler warnings due to time_t being 64bit.
685 He also made recent Microsoft compilers use _strdup() instead of strdup().
687 - Brad House's man pages for ares_save_options() and ares_destroy_options()
690 - Ashish Sharma provided a patch for supporting multiple entries in the
691 /etc/hosts file. Patch edited for coding style and functionality by me
696 - Shmulik Regev brought cryptographically secure transaction IDs:
698 The c-ares library implementation uses a DNS "Transaction ID" field that is
699 seeded with a pseudo random number (based on gettimeofday) which is
700 incremented (++) between consecutive calls and is therefore rather
701 predictable. In general, predictability of DNS Transaction ID is a well
702 known security problem (e.g.
703 http://bak.spc.org/dms/archive/dns_id_attack.txt) and makes a c-ares based
704 implementation vulnerable to DNS poisoning. Credit goes to Amit Klein
705 (Trusteer) for identifying this problem.
707 The patch I wrote changes the implementation to use a more secure way of
708 generating unique IDs. It starts by obtaining a key with reasonable entropy
709 which is used with an RC4 stream to generate the cryptographically secure
712 Note that the key generation code (in ares_init:randomize_key) has two
713 versions, the Windows specific one uses a cryptographically safe function
714 provided (but undocumented :) by the operating system (described at
715 http://blogs.msdn.com/michael_howard/archive/2005/01/14/353379.aspx). The
716 default implementation is a bit naive and uses the standard 'rand'
717 function. Surely a better way to generate random keys exists for other
720 The patch can be tested by using the adig utility and using the '-s' option.
722 - Brad House added ares_save_options() and ares_destroy_options() that can be
723 used to keep options for later re-usal when ares_init_options() is used.
725 Problem: Calling ares_init() for each lookup can be unnecessarily resource
726 intensive. On windows, it must LoadLibrary() or search the registry
727 on each call to ares_init(). On unix, it must read and parse
728 multiple files to obtain the necessary configuration information. In
729 a single-threaded environment, it would make sense to only
730 ares_init() once, but in a heavily multi-threaded environment, it is
731 undesirable to ares_init() and ares_destroy() for each thread created
734 Solution: Create ares_save_options() and ares_destroy_options() functions to
735 retrieve and free options obtained from an initialized channel. The
736 options populated can be used to pass back into ares_init_options(),
737 it should populate all needed fields and not retrieve any information
738 from the system. Probably wise to destroy the cache every minute or
739 so to prevent the data from becoming stale.
741 - Daniel S added ares_process_fd() to allow applications to ask for processing
742 on specific sockets and thus avoiding select() and associated
743 functions/macros. This function will be used by upcoming libcurl releases
744 for this very reason. It also made me export the ares_socket_t type in the
745 public ares.h header file, since ares_process_fd() uses that type for two of
750 - Ravi Pratap fixed a flaw in the init_by_resolv_conf() function for windows
751 that could cause it to return a bad return code.
755 - Yang Tse: Provide ares_getopt() command-line parser function as a source
756 code helper function, not belonging to the actual c-ares library.
760 - Vlad Dinulescu added ares_parse_ns_reply().
764 - Yang Tse: Fix failure to get the search sequence of /etc/hosts and
765 DNS from /etc/nsswitch.conf, /etc/host.conf or /etc/svc.conf when
766 /etc/resolv.conf did not exist or was unable to read it.
770 - Install ares_dns.h too
772 - Michael Wallner fixed this problem: When I set domains in the options
773 struct, and there are domain/search entries in /etc/resolv.conf, the domains
774 of the options struct will be overridden.
778 - Yang Tse removed a couple of potential zero size memory allocations.
780 - Andreas Rieke fixed the line endings in the areslib.dsp file that I (Daniel)
781 broke in the 1.3.2 release. We should switch to a system where that file is
782 auto-generated. We could rip some code for that from curl...
784 Version 1.3.2 (November 3, 2006)
788 - Prevent ares_getsock() to overflow if more than 16 sockets are used.
792 - Guilherme Balena Versiani: I noted a strange BUG in Win32 port
793 (ares_init.c/get_iphlpapi_dns_info() function): when I disable the network
794 by hand or disconnect the network cable in Windows 2000 or Windows XP, my
795 application gets 127.0.0.1 as the only name server. The problem comes from
796 'GetNetworkParams' function, that returns the empty string "" as the only
797 name server in that case. Moreover, the Windows implementation of
798 inet_addr() returns INADDR_LOOPBACK instead of INADDR_NONE.
804 o made ares_version.h use extern "C" for c++ compilers
805 o fixed compiler warnings in ares_getnameinfo.c
806 o fixed a buffer position init for TCP reads
810 - Ravi Pratap fixed ares_getsock() to actually return the proper bitmap and
813 Version 1.3.1 (June 24, 2006)
817 - Gisle Vanem added getopt() to the ahost program. Currently accepts
818 only [-t {a|aaaa}] to specify address family in ares_gethostbyname().
822 - (wahern) Removed "big endian" DNS section and RR data integer parser
823 macros from ares_dns.h, which break c-ares on my Sparc64. Bit-wise
824 operations in C operate on logical values. And in any event the octets are
825 already in big-endian (aka network) byte order so they're being reversed
826 (thus the source of the breakage).
830 - William Ahern handles EAGAIN/EWOULDBLOCK errors in most of the I/O calls
833 TODO: Handle one last EAGAIN for a UDP socket send(2) in
838 - Bram Matthys brought my attention to a libtool peculiarity where detecting
839 things such as C++ compiler actually is a bad thing and since we don't need
840 that detection I added a work-around, much inspired by a previous patch by
841 Paolo Bonzini. This also shortens the configure script quite a lot.
845 - Nick Mathewson added the ARES_OPT_SOCK_STATE_CB option that when set makes
846 c-ares call a callback on socket state changes. A better way than the
847 ares_getsock() to get full control over the socket state.
851 - Alexander Lazic improved the getservbyport_r() configure check.
855 - Alexander Lazic pointed out that the buildconf should use the ACLOCAL_FLAGS
856 variable for easier controlling what it does and how it runs.
860 - James Bursa fixed c-ares to find the hosts file on RISC OS, and made it
861 build with newer gcc versions that no longer defines "riscos".
865 - Daniel Stenberg added ares_getsock() that extracts the set of sockets to
866 wait for action on. Similar to ares_fds() but not restricted to using
867 select() for the waiting.
871 - Yang Tse fixed some send() / recv() compiler warnings
875 - Added constants that will be used by ares_getaddrinfo
877 - Made ares_getnameinfo use the reentrant getservbyport (getservbyport_r) if it
878 is available to ensure it works properly in a threaded environment.
882 - configure fix for detecting a member in the sockaddr_in6 struct which failed
883 on ipv6-enabled HP-UX 11.00
885 Version 1.3.0 (August 29, 2005)
889 - Alfredo Tupone provided a fix for the Windows code in get_iphlpapi_dns_info()
890 when getting the DNS server etc.
894 - Added some checks for the addrinfo structure.
900 Make UDP sockets non-blocking. I've confirmed that at least on Linux 2.4 a
901 read event can come back from poll() on a valid SOCK_DGRAM socket but
902 recv(2) will still block. This patch doesn't ignore EAGAIN in
903 read_udp_packets(), though maybe it should. (This patch was edited by Daniel
904 Stenberg and a new configure test was added (imported from curl's configure)
905 to properly detect what non-blocking socket approach to use.)
907 I'm not quite sure how this was happening, but I've been seeing PTR queries
908 which seem to return empty responses. At least, they were empty when calling
909 ares_expand_name() on the record. Here's a patch which guarantees to
910 NUL-terminate the expanded name. The old behavior failed to NUL-terminate if
911 len was 0, and this was causing strlen() to run past the end of the buffer
912 after calling ares_expand_name() and getting ARES_SUCCESS as the return
913 value. If q is not greater than *s then it's equal and *s is always
914 allocated with at least one byte.
918 - Added ares_getnameinfo which mimics the getnameinfo API (another feature
919 that could use testing).
923 - Added an inet_ntop function from BIND for systems that do not have it.
927 - Made sortlist support IPv6 (this can probably use some testing).
929 - Made sortlist support CIDR matching for IPv4.
933 - Added preliminary IPv6 support to ares_gethostbyname. Currently, sortlist
934 does not work with IPv6. Also provided an implementation of bitncmp from
935 BIND for systems that do not supply this function. This will be used to add
936 IPv6 support to sortlist.
938 - Made ares_gethostbyaddr support IPv6 by specifying AF_INET6 as the family.
939 The function can lookup IPv6 addresses both from files (/etc/hosts) and
944 - Tupone Alfredo fixed includes of arpa/nameser_compat.h to build fine on Mac
949 - Dominick Meglio: Provided implementations of inet_net_pton and inet_pton
950 from BIND for systems that do not include these functions.
954 - Dominick Meglio added ares_parse_aaaa_reply.c and did various
955 adjustments. The first little steps towards IPv6 support!
959 - Fixed the VC project and makefile to use ares_cancel and ares_version
963 - The released ares_version.h from 1.2.1 says 1.2.0 due to a maketgz flaw.
966 Version 1.2.1 (October 20, 2004)
970 - Henrik Stoerner fix: got a report that Tru64 Unix (the unix from Digital
971 when they made Alpha's) uses /etc/svc.conf for the purpose fixed below for
972 other OSes. He made c-ares check for and understand it if present.
974 - Now c-ares will use local host name lookup _before_ DNS resolving by default
975 if nothing else is told.
979 - Henrik Stoerner: found out that c-ares does not look at the /etc/host.conf
980 file to determine the sequence in which to search /etc/hosts and DNS. So on
981 systems where this order is defined by /etc/host.conf instead of a "lookup"
982 entry in /etc/resolv.conf, c-ares will always default to looking in DNS
983 first, and /etc/hosts second.
987 1) resolv.conf (for the "lookup" line);
988 2) nsswitch.fon (for the "hosts:" line);
989 3) host.conf (for the "order" line).
993 - Dominick Meglio patched: C-ares on Windows assumed that the HOSTS file is
994 located in a static location. It assumed
995 C:\Windows\System32\Drivers\Etc. This is a poor assumption to make. In fact,
996 the location of the HOSTS file can be changed via a registry setting.
998 There is a key called DatabasePath which specifies the path to the HOSTS
1000 http://www.microsoft.com/technet/itsolutions/network/deploy/depovg/tcpip2k.mspx
1002 The patch will make c-ares correctly consult the registry for the location
1007 - Gisle Vanem fixed the MSVC build files.
1011 - Gisle Vanem made c-ares build and work with his Watt-32 TCP/IP stack.
1015 - Harshal Pradhan made a minor syntax change in ares_init.c to make it build
1020 - Made the lib get built static only if --enable-debug is used.
1022 - Gisle Vanem fixed:
1024 Basically in loops like handle_errors(), 'query->next' was assigned a local
1025 variable and then query was referenced after the memory was freed by
1026 next_server(). I've changed that so next_server() and end_query() returns
1027 the next query. So callers should use this ret-value.
1029 The next problem was that 'server->tcp_buffer_pos' had a random value at
1030 entry to 1st recv() (luckily causing Winsock to return ENOBUFS).
1032 I've also added a ares_writev() for Windows to streamline the code a bit
1036 - Fixed a few variable return types for some system calls. Made configure
1037 check for ssize_t to make it possible to use that when receiving the send()
1038 error code. This is necessary to prevent compiler warnings on some systems.
1040 - Made configure create config.h, and all source files now include setup.h that
1041 might include the proper config.h (or a handicrafted alternative).
1043 - Switched to 'ares_socket_t' type for sockets in ares, since Windows don't
1046 - automake-ified and libool-ified c-ares. Now it builds libcares as a shared
1047 lib on most platforms if wanted. (This bloated the size of the release
1048 archive with another 200K!)
1050 - Makefile.am now uses Makefile.inc for the c sources, h headers and man
1051 pages, to make it easier for other makefiles to use the exact same set of
1054 - Adjusted 'maketgz' to use the new automake magic when building distribution
1057 - Anyone desires HTML and/or PDF versions of the man pages in the release
1061 - Günter Knauf made c-ares build and run on Novell Netware.
1064 - Gisle Vanem provided Makefile.dj to build with djgpp, added a few more djgpp
1065 fixes and made ares not use 'errno' to provide further info on Windows.
1068 - Gisle Vanem made it build with djgpp and run fine with the Watt-32 stack.
1071 - Gisle Vanem's init patch for Windows:
1073 The init_by_resolv_conf() function fetches the DNS-server(s)
1074 from a series of registry branches.
1076 This can be wrong in the case where DHCP has assigned nameservers, but the
1077 user has overridden these servers with other prefered settings. Then it's
1078 wrong to use the DHCPNAMESERVER setting in registry.
1080 In the case of no global DHCP-assigned or fixed servers, but DNS server(s)
1081 per adapter, one has to query the adapter branches. But how can c-ares know
1082 which adapter is valid for use? AFAICS it can't. There could be one adapter
1083 that is down (e.g. a VPN adapter).
1085 So it's better to leave this to the IP Helper API (iphlapi) available in
1086 Win-98/2000 and later. My patch falls-back to the old way if not available.
1089 - James Bursa fixed an init issue for RISC OS.
1092 - Nico Stappenbelt reported that when processing domain and search lines in
1093 the resolv.conf file, the first entry encountered is processed and used as
1094 the search list. According to the manual pages for both Linux, Solaris and
1095 Tru64, the last entry of either a domain or a search field is used.
1097 This is now adjusted in the code
1099 Version 1.2.0 (April 13, 2004)
1102 - Updated various man pages to look nicer when converted to HTML on the web
1106 - Dirk Manske provided a new function that is now named ares_cancel(). It is
1107 used to cancel/cleanup a resolve/request made using ares functions on the
1108 given ares channel. It does not destroy/kill the ares channel itself.
1110 - Dominick Meglio cleaned up the formatting in several man pages.
1113 - Dominick Meglio's new ares_expand_string. A helper function when decoding
1114 incoming DNS packages.
1116 - Daniel Stenberg modified the Makefile.in to use a for loop for the man page
1117 installation to improve overview and make it easier to add man pages.
1119 Version 1.1.0 (March 11, 2004)
1122 - Gisle Vanem improved build on Windows.
1125 - Dan Fandrich found a flaw in the Feb 22 fix.
1127 - Added better configure --enable-debug logic (taken from the curl configure
1128 script). Added acinclude.m4 to the tarball.
1131 - Removed ares_free_errmem(), the function, the file and the man page. It was
1132 not used and it did nothing.
1134 - Fixed a lot of code that wasn't "64bit clean" and thus caused a lot of
1135 compiler warnings on picky compilers.
1138 - Dominick Meglio made ares init support multiple name servers in the
1139 NameServer key on Windows.
1142 - Modified ares_private.h to include libcurl's memory debug header if
1143 CURLDEBUG is set. This makes all the ares-functions supervised properly by
1144 the curl test suite. This also forced me to add inclusion of the
1145 ares_private.h header in a few more files that are using some kind of
1146 memory-related resources.
1148 - Made the makefile only build ahost and adig if 'make demos' is used.
1151 - Dirk Manske made ares_version.h installed with 'make install'
1154 - ares_free_errmem() is subject for removal, it is simply present for future
1155 purposes, and since we removed the extra parameter in strerror() it won't
1157 - configure --enable-debug now enables picky compiler options if gcc is used
1158 - fixed several compiler warnings --enable-debug showed and Joerg Mueller-Tolk
1161 Version 1.0.0 (February 3, 2004)
1164 - now we produce the libcares.a library instead of the previous libares.a
1165 since we are no longer compatible
1169 - ares_strerror() has one argument less. This is the first official
1170 modification of the existing provided ares API.
1174 - Dirk Manske fixed how the socket is set non-blocking.
1178 - Dominick Meglio made the private gettimeofday() become ares_gettimeofday()
1179 instead in order to not pollute the name space and risk colliding with
1180 other libraries' versions of this function.
1182 * October 24, 2003. Daniel Stenberg
1184 Added ares_version().
1186 Version 1.0-pre1 (8 October 2003)
1188 - James Bursa made it run on RISC OS
1190 - Dominick Meglio made it run fine on NT4
1192 - Duncan Wilcox made it work fine on Mac OS X
1194 - Daniel Stenberg adjusted the windows port
1196 - liren at vivisimo.com made the initial windows port
1198 * Imported the sources from ares 1.1.1