Commit Graph

783 Commits

Author SHA1 Message Date
Florian Weimer
dbc0e02dbb resolv: Fix tst-resolv-short-response for older GCC (bug 32042)
Previous GCC versions do not support the C23 change that
allows labels on declarations.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
(cherry picked from commit ec119972cb)
2024-08-01 21:12:01 +02:00
Florian Weimer
7285630e0e resolv: Track single-request fallback via _res._flags (bug 31476)
This avoids changing _res.options, which inteferes with change
detection as part of automatic reloading of /etc/resolv.conf.

Reviewed-by: DJ Delorie <dj@redhat.com>
(cherry picked from commit 868ab8923a)
2024-07-24 15:58:18 +02:00
Florian Weimer
df808340fd resolv: Do not wait for non-existing second DNS response after error (bug 30081)
In single-request mode, there is no second response after an error
because the second query has not been sent yet.  Waiting for it
introduces an unnecessary timeout.

Reviewed-by: DJ Delorie <dj@redhat.com>
(cherry picked from commit af625987d6)
2024-07-24 14:56:29 +02:00
Florian Weimer
c44ea7914c resolv: Allow short error responses to match any query (bug 31890)
Reviewed-by: DJ Delorie <dj@redhat.com>
(cherry picked from commit 691a3b2e9b)
2024-07-24 14:56:03 +02:00
Martin Sebor
92d5c52aaa resolv: Avoid GCC 12 false positive warning [BZ #28439].
Replace a call to sprintf with an equivalent pair of stpcpy/strcpy calls
to avoid a GCC 12 -Wformat-overflow false positive due to recent optimizer
improvements.

(cherry picked from commit eb73b87897)
2023-01-11 13:34:00 +01:00
Florian Weimer
044755e2fa resolv: Fix building tst-resolv-invalid-cname for earlier C standards
This fixes this compiler error:

tst-resolv-invalid-cname.c: In function ‘test_mode_to_string’:
tst-resolv-invalid-cname.c:164:10: error: label at end of compound statement
     case test_mode_num:
          ^~~~~~~~~~~~~

Fixes commit 9caf782276
("resolv: Add new tst-resolv-invalid-cname").

(cherry picked from commit d09aa4a172)
2022-09-21 19:37:24 +02:00
Florian Weimer
2def56a349 nss_dns: Rewrite _nss_dns_gethostbyname4_r using current interfaces
Introduce struct alloc_buffer to this function, and use it and
struct ns_rr_cursor in gaih_getanswer_slice.  Adjust gaih_getanswer
and gaih_getanswer_noaaaa accordingly.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 1d495912a7)
(conflict in resolv/nss_dns/dns-host.c due to missing noaaaa support)
2022-09-21 19:37:24 +02:00
Florian Weimer
480c820493 resolv: Add new tst-resolv-invalid-cname
This test checks resolution through CNAME chains that do not contain
host names (bug 12154).

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 9caf782276)
2022-09-21 19:37:24 +02:00
Florian Weimer
c36e7cca35 nss_dns: In gaih_getanswer_slice, skip strange aliases (bug 12154)
If the name is not a host name, skip adding it to the result, instead
of reporting query failure.  This fixes bug 12154 for getaddrinfo.

This commit still keeps the old parsing code, and only adjusts when
a host name is copied.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 32b599ac8c)
2022-09-21 19:37:24 +02:00
Florian Weimer
9abc40d9b5 nss_dns: Rewrite getanswer_r to match getanswer_ptr (bug 12154, bug 29305)
Allocate the pointer arrays only at the end, when their sizes
are known.  This addresses bug 29305.

Skip over invalid names instead of failing lookups.  This partially
fixes bug 12154 (for gethostbyname, fixing getaddrinfo requires
different changes).

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit d101d836e7)
2022-09-21 19:37:17 +02:00
Florian Weimer
7267341ec1 nss_dns: Remove remnants of IPv6 address mapping
res_use_inet6 always returns false since commit 3f8b44be0a
("resolv: Remove support for RES_USE_INET6 and the inet6 option").

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit a7fc30b522)
2022-09-21 19:36:12 +02:00
Florian Weimer
32e5db3768 nss_dns: Rewrite _nss_dns_gethostbyaddr2_r and getanswer_ptr
The simplification takes advantage of the split from getanswer_r.
It fixes various aliases issues, and optimizes NSS buffer usage.
The new DNS packet parsing helpers are used, too.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit e32547d661)
2022-09-21 19:36:12 +02:00
Florian Weimer
d9c979abf9 nss_dns: Split getanswer_ptr from getanswer_r
And expand the use of name_ok and qtype in getanswer_ptr (the
former also in getanswer_r).

After further cleanups, not much code will be shared between the
two functions.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 0dcc43e998)
2022-09-21 19:36:12 +02:00
Florian Weimer
e7c03f4765 resolv: Add DNS packet parsing helpers geared towards wire format
The public parser functions around the ns_rr record type produce
textual domain names, but usually, this is not what we need while
parsing DNS packets within glibc.  This commit adds two new helper
functions, __ns_rr_cursor_init and __ns_rr_cursor_next, for writing
packet parsers, and struct ns_rr_cursor, struct ns_rr_wire as
supporting types.

In theory, it is possible to avoid copying the owner name
into the rname field in __ns_rr_cursor_next, but this would need
more functions that work on compressed names.

Eventually, __res_context_send could be enhanced to preserve the
result of the packet parsing that is necessary for matching the
incoming UDP packets, so that this works does not have to be done
twice.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 857c890d9b)
2022-09-21 19:36:12 +02:00
Florian Weimer
c288e032ae resolv: Add internal __ns_name_length_uncompressed function
This function is useful for checking that the question name is
uncompressed (as it should be).

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 78b1a4f0e4)
2022-09-21 19:36:12 +02:00
Florian Weimer
bb8adbba4f resolv: Add the __ns_samebinaryname function
During packet parsing, only the binary name is available.  If the name
equality check is performed before conversion to text, we can sometimes
skip the last step.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 394085a34d)
2022-09-21 19:36:12 +02:00
Florian Weimer
4d2e67d6e5 resolv: Add internal __res_binary_hnok function
During package parsing, only the binary representation is available,
and it is convenient to check that directly for conformance with host
name requirements.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit c79327bf00)
2022-09-21 19:36:12 +02:00
Florian Weimer
6a833d798e resolv: Add tst-resolv-aliases
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 87aa98aa80)
2022-09-21 19:36:12 +02:00
Florian Weimer
1a3afdfe31 resolv: Add tst-resolv-byaddr for testing reverse lookup
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 0b99828d54)
2022-09-21 19:36:12 +02:00
Siddhesh Poyarekar
2d2d9f2b48 Move malloc hooks into a compat DSO
Remove all malloc hook uses from core malloc functions and move it
into a new library libc_malloc_debug.so.  With this, the hooks now no
longer have any effect on the core library.

libc_malloc_debug.so is a malloc interposer that needs to be preloaded
to get hooks functionality back so that the debugging features that
depend on the hooks, i.e. malloc-check, mcheck and mtrace work again.
Without the preloaded DSO these debugging features will be nops.
These features will be ported away from hooks in subsequent patches.

Similarly, legacy applications that need hooks functionality need to
preload libc_malloc_debug.so.

The symbols exported by libc_malloc_debug.so are maintained at exactly
the same version as libc.so.

Finally, static binaries will no longer be able to use malloc
debugging features since they cannot preload the debugging DSO.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-22 18:37:59 +05:30
Florian Weimer
20be978f05 resolv: Do not install libnss_dns.a, libnss_dns.so
Fixes commit e1fcf21474 ("resolv: Move nss_dns into libc").
2021-07-20 12:29:27 +02:00
Florian Weimer
ee5ed99922 nss: Directly load nss_dns, without going through dlsym/dlopen
This partially fixes static-only NSS support (bug 27959): The dns
module no longer needs dlopen.  Support for disabling dlopen altogher
remains to be added.

This commit introduces module_load_builtin into nss/nss_module.c, which
handles the common parts of loading the built-in nss_files and nss_dns
modules.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:57 +02:00
Florian Weimer
e1fcf21474 resolv: Move nss_dns into libc
No abilist updates are needed because the symbols were GLIBC_PRIVATE.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:57 +02:00
Florian Weimer
ea9878ec27 resolv: Move res_query functions into libc
This switches to public symbols without __ prefixes, due to improved
namespace management in glibc.

The script was used with --no-new-version to move the symbols
__res_nquery, __res_nquerydomain, __res_nsearch, __res_query,
__res_querydomain, __res_search, res_query, res_querydomain,
res_search.  The public symbols res_nquery, res_nquerydomain,
res_nsearch, res_ownok, res_query, res_querydomain, res_search
were added with make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:57 +02:00
Florian Weimer
21a497cc58 resolv: Move res_mkquery, res_nmkquery into libc
This switches to public symbols without __ prefixes, due to improved
namespace management in glibc.

The symbols res_mkquery, __res_mkquery, __res_nmkquery were
moved with the script (using --no-new-version).
res_mkquery@@GLIBC_2.34, res_nmkquery@@GLIBC_2.34 were added using
make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:57 +02:00
Florian Weimer
b165c65c35 resolv: Move res_send, res_nsend into libc
Switch to public symbols without __ prefix (due to improved
namespace management).

__res_send, __res_nsend were moved using the script (with
--no-new-version).  res_send@@GLIBC_2.34 and res_nsend@@GLIBC_2.34
were added using make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:45 +02:00
Florian Weimer
66ac4268f4 resolv: Move res_hostalias into its own file, along with hostalias
These deprecated symbols continue to be exported from libresolv.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
be5773e166 resolv: Move __res_context_hostalias into its own file and into libc
And reformat it to GNU style.  Remove the unecessary setbuf call.
Use __fgets_unlocked for PLT avoidance; no locking is required here.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
7131727c6b resolv: Move res_queriesmatch to its own file and into libc
And reformat it to GNU style.

The treatment of this function matches res_nameinquery, for the
reasons stated there.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
72a51ac647 resolv: Move res_nameinquery to its own file and into libc
And reformat to GNU style.

This deprecated function is used in the implementation of the stub
resolver (for now).  Keep the public symbol in libresolv for now
(so that no new symbol version is needed), and add a forwarder to
libresolv.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
762a2b2d34 resolv: Move ns_samename into its own file, and into libc
But only as an internal symbol, __libc_ns_samename.  The libresolv
ABI is preserved.  This is because the function is deprecated, and
it does not make sense to add new symbol versions for deprecated
functions.

Also reformat the implementation to GNU style.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
08d4a98070 resolv: Move ns_makecanon into its own file, and into libc
But only as an internal symbol, __libc_ns_makecanon.  The libresolv
ABI is preserved.  This is because the function is deprecated, and
it does not make sense to add new symbol versions for deprecated
functions.

Also reformat the implementation to GNU style.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
17d0407a5c resolv: Move res_isourserver to its own file and reformat to GNU style
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
9515126f90 resolv: Move __res_get_nsaddr to its own file and into libc
Eliminate the use of the EXT macro from it because it does not
add clarity.  The function was added to res_send.c in 2015, and
the copyright year reflects that.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
2fbe5860d3 resolv: Rename res_comp.c to res-name-checking.c and move into libc
This reflects what the remaining functions in the file do.

The __res_dnok, __res_hnok, __res_mailok, __res_ownok were moved
with the script, using --no-new-version, and turned into compat
symbols.  __libc_res_dnok@@GLIBC_PRIVATE and
__libc_res_hnok@@GLIBC_PRIVATE are added for internal use, to avoid
accidentally binding to compatibility symbols.  The new public
symbols res_dnok, res_hnok, res_mailok, res_ownok were added using
make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
391e02236b resolv: Move dn_skipname to its own file and into libc
And reformat it to GNU style.

dn_skipname is used outside glibc, so do not deprecate it,
and export it as dn_skipname (not __dn_skipname).  Due to internal
users, provide a __libc_dn_skipname alias, and keep __dn_skipname
as a pure compatibility symbol.

__dn_skipname@GLIBC_2.0 was moved using the script, and
dn_skipname@@GLIBC_2.34 was added using make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
fd8a87c0c1 resolv: Move dn_comp to its own file and into libc
And reformat it to GNU style.

dn_comp is used in various programs, so keep it as a non-deprecated
symbol.  Switch to dn_comp (not __dn_comp) for the ABI name.  There
are no internal users, so interposition is not a problem.

The __dn_comp symbol was moved with scripts/move-symbol-to-libc.py
--no-new-version.  dn_comp@@GLIBC_2.34 was added with
make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
7ec366a08a resolv: Move _getlong, _getshort, __putlong, __putshort to res-putget
And reformat to GNU style.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
640bbdf71c resolv: Move dn_expand to its own file and into libc
And reformat to GNU style.

This switches back to the dn_expand name for the ABI symbol and turns
__dn_expand into a compatibility symbol.  With the improved namespace
management in current glibc, it is no longer necessary to use a
private namespace symbol.  To avoid old code binding to a
GLIBC_PRIVATE symbol by accident, use __libc_dn_expand for the
internal symbol name.

The symbols dn_expand, __dnexpand were moved using
scripts/move-symbol-to-libc.py, followed by an adjustment to make
dn_expand the only GLIBC_2.34 symbol.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
13e1f86706 resolv: Move ns_name_compress into its own file and into libc
And reformat to GNU style.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
7ed1ac6da3 resolv: Move ns_name_pack into its own file and into libc
And reformat to GNU style, and eliminate the labellen function.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
276e9822b3 resolv: Move ns_name_pton into its own file and into libc
And reformat to GNU style, and eliminate the digits variable.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
4e1d3db1e8 resolv: Move ns_name_uncompress into its own file and into libc
And reformat to GNU style.  Check for negative error returns
(instead of -1).

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
cff2c78c51 resolv: Move ns_name_skip to its own file and into libc (bug 28091)
And reformat to GNU style.  Avoid out-of-bounds pointer arithmetic.
This also results in a fix of bug 28091 due to the additional packet
length checks.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@systemhalted.org>
2021-07-19 07:56:13 +02:00
Florian Weimer
248dbed118 resolv: Deprecate legacy interfaces in libresolv
Debugging interfaces: p_*, fp_*, and sym_* could conceivably be
used to produce debug out, but these functions have not been
updated to parse more resource records, so they are not very useful
today.  Likewise for ns_sprintrr and ns_sprintrrf.  ns_format_ttl and
ns_parse_ttl are related to these.

Internal implementation details: res_isourserver is probably only
useful in the implementation of a stub resolver, and so is
res_nameinquery.

Unclear semantics and bad performance: ns_samedomain, ns_subdomain,
ns_makecanon, ns_samename do textual converions & copies instead of
checking equivalence of the wire format.

inet_neta cannot handle IPv6 addresses.

res_hostalias has been superseded by getaddrinfo with AI_CANONNAME.
hostalias is not thread-safe.

Some functions have int as size arguments instead of size_t, so they
do not follow current coding practices.  However, dn_expand and
b64_ntop are somewhat widely used (to name just two examples), so
deprecating them seems problematic.

Reviewed-by: Carlos O'Donell <carlos@systemhalted.org>
2021-07-19 07:55:42 +02:00
Florian Weimer
820bb23ff0 resolv: Move ns_name_unpack to its own file and into libc
Reformat to GNU style. Avoid out-of-bounds buffer arithmetic.
Eliminate the labellen function.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 09:00:27 +02:00
Florian Weimer
ee3639e0fe resolv: Remove unnecessary res_isourserver_p call from send_dg
As the comment indicates, the check is unnecessary due to the way the
UDP socket is set up.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 09:00:24 +02:00
Florian Weimer
adcc572a29 resolv: Move ns_name_ntop to its own file and into libc
Reformat to GNU style.  Avoid out-of-bounds pointer arithmetic
(e.g., use eom - dn < 2 instead of dn + 1 >= eom).  Inline the
labellen function and fold the compression pointer check into
the length check (l >= 64).  Assume ASCII encoding.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 08:39:31 +02:00
Florian Weimer
2ff32dd492 nss_dns: Do not use deprecated packet parsing functions
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 08:39:02 +02:00
Florian Weimer
389c1114d1 resolv: Sort Makefile routines and Versions lexicographically
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 08:37:45 +02:00