This commit enhances the stub resolver to reload the configuration
in the per-thread _res object if the /etc/resolv.conf file has
changed. The resolver checks whether the application has modified
_res and will not overwrite the _res object in that case.
The struct resolv_context mechanism is used to check the
configuration file only once per name lookup.
This commit adds the remaining unchanging members (which are loaded
from /etc/resolv.conf) to struct resolv_conf.
The extended name server list is currently not used by the stub
resolver. The switch depends on a cleanup: The _u._ext.nssocks
array stores just a single socket, and needs to be replaced with
a single socket value.
(The compatibility gethostname implementation does not use the
extended addres sort list, either. Updating the compat code is
not worthwhile.)
This change uses the extended resolver state in struct resolv_conf to
store the search list. If applications have not patched the _res
object directly, this extended search list will be used by the stub
resolver during name resolution.
This change provides additional resolver configuration state which
is not exposed through the _res ABI. It reuses the existing
initstamp field in the supposedly-private part of _res. Some effort
is undertaken to avoid memory safety issues introduced by applications
which directly patch the _res object.
With this commit, only the initstamp field is moved into struct
resolv_conf. Additional members will be added later, eventually
migrating the entire resolver configuration.
struct resolv_context objects provide a temporary resolver context
which does not change during a name lookup operation. Only when the
outmost context is created, the stub resolver configuration is
verified to be current (at present, only against previous res_init
calls). Subsequent attempts to obtain the context will reuse the
result of the initial verification operation.
struct resolv_context can also be extended in the future to store
data which needs to be deallocated during thread cancellation.
Some Linux kernels have very aggressive ICMP rate limiting on the
loopback interface. This commit introduces a minimal echoing DNS server
inside the network namespace, so that there is no need for ICMP error
messages anymore.
Many callers of __res_maybe_init also call _res_hconf_init.
Additional calls to the latter do not hurt because the function
does its work only once. (/etc/hosts.conf is not reloaded or
even checked for changes.) This means that we can simplify the
code by calling _res_hconf_init directly from __res_vinit.
Every file that uses libc_hidden_nolink_sunrpc or
libnsl_hidden_nolink_def needs to include shlib-compat.h. Currently,
most of them are getting it via stdio.h, because libio.h refers to
SHLIB_COMPAT when _LIBC is defined, so it includes shlib-compat.h. My
experimental patch to not install libio.h breaks that chain; stdio.h
no longer pulls in libio.h even for internal users.
Accordingly, this patch adds #include <shlib-compat.h> to many files
in sunrpc/ and nis/. There are also a small number of really obvious
fixups to includes that caught my eye while proofreading the patch -
not including headers twice in a row, not worrying about portability
to Ultrix anymore, sort of thing.
* nis/nis_add.c, nis/nis_addmember.c, nis/nis_call.c
* nis/nis_checkpoint.c, nis/nis_clone_dir.c, nis/nis_clone_obj.c
* nis/nis_clone_res.c, nis/nis_creategroup.c, nis/nis_defaults.c
* nis/nis_destroygroup.c, nis/nis_domain_of.c
* nis/nis_domain_of_r.c, nis/nis_error.c, nis/nis_file.c
* nis/nis_free.c, nis/nis_getservlist.c, nis/nis_ismember.c
* nis/nis_local_names.c, nis/nis_lookup.c, nis/nis_mkdir.c
* nis/nis_modify.c, nis/nis_ping.c, nis/nis_print.c
* nis/nis_print_group_entry.c, nis/nis_remove.c
* nis/nis_removemember.c, nis/nis_rmdir.c, nis/nis_server.c
* nis/nis_subr.c, nis/nis_table.c, nis/nis_util.c
* nis/nis_verifygroup.c, nis/nis_xdr.c, nis/yp_xdr.c
* nis/ypclnt.c, nis/ypupdate_xdr.c, sunrpc/auth_des.c
* sunrpc/auth_none.c, sunrpc/auth_unix.c, sunrpc/authdes_prot.c
* sunrpc/authuxprot.c, sunrpc/clnt_gen.c, sunrpc/clnt_perr.c
* sunrpc/clnt_raw.c, sunrpc/clnt_simp.c, sunrpc/clnt_tcp.c
* sunrpc/clnt_udp.c, sunrpc/clnt_unix.c, sunrpc/des_crypt.c
* sunrpc/des_soft.c, sunrpc/get_myaddr.c, sunrpc/key_call.c
* sunrpc/key_prot.c, sunrpc/netname.c, sunrpc/pm_getmaps.c
* sunrpc/pm_getport.c, sunrpc/pmap_clnt.c, sunrpc/pmap_prot.c
* sunrpc/pmap_prot2.c, sunrpc/pmap_rmt.c, sunrpc/publickey.c
* sunrpc/rpc_cmsg.c, sunrpc/rpc_dtable.c, sunrpc/rpc_prot.c
* sunrpc/rpc_thread.c, sunrpc/rtime.c, sunrpc/svc.c
* sunrpc/svc_auth.c, sunrpc/svc_raw.c, sunrpc/svc_run.c
* sunrpc/svc_tcp.c, sunrpc/svc_udp.c, sunrpc/svc_unix.c
* sunrpc/svcauth_des.c, sunrpc/xdr.c, sunrpc/xdr_array.c
* sunrpc/xdr_float.c, sunrpc/xdr_intXX_t.c, sunrpc/xdr_mem.c
* sunrpc/xdr_rec.c, sunrpc/xdr_ref.c, sunrpc/xdr_sizeof.c
* sunrpc/xdr_stdio.c: Include shlib-compat.h.
* sunrpc/des_crypt.c, sunrpc/des_soft.c: No need to include
abi-versions.h as well as shlib-compat.h.
* sunrpc/get_myaddr.c: Remove obsolete comment.
* sunrpc/pmap_rmt.c: Remove obsolete comment and #undef.
* sunrpc/rpc_thread.c: Include libc-lock.h only once.
* resolv/res_libc.c: Include shlib-compat.h only once.
The types affected are __sig_atomic_t, sig_atomic_t, __sigset_t,
sigset_t, sigval_t, sigevent_t, and siginfo_t. __sig_atomic_t is a
scalar, so it's now directly available from bits/types.h. The others
get bits/types/ headers.
Side effects include: There have been small changes to which
non-signal headers expose which subset of the signal-related types.
A couple of architectures' nested siginfo_t fields had to be renamed
to prevent undesired macro expansion. Internal code that wants to
manipulate signal masks must now include <sigsetops.h> (which is not
installed) and should be aware that __sigaddset, __sigandset,
__sigdelset, __sigemptyset, and __sigorset no longer return a value
(unlike the public API). Relatedly, the public signal.h no longer
declares any of those functions. The obsolete sigmask() macro no
longer has a system-specific definition -- in the cases where it
matters, it didn't work anyway.
New Linux architectures should create bits/siginfo-arch.h and/or
bits/siginfo-consts-arch.h to customize their siginfo_t, rather than
duplicating everything in bits/siginfo.h (which no longer exists).
Add new __SI_* macros if necessary. Ports to other operating systems
are strongly encouraged to generalize this scheme further.
* bits/sigevent-consts.h
* bits/siginfo-consts.h
* bits/types/__sigset_t.h
* bits/types/sigevent_t.h
* bits/types/siginfo_t.h
* sysdeps/unix/sysv/linux/bits/sigevent-consts.h
* sysdeps/unix/sysv/linux/bits/siginfo-consts.h
* sysdeps/unix/sysv/linux/bits/types/__sigset_t.h
* sysdeps/unix/sysv/linux/bits/types/sigevent_t.h
* sysdeps/unix/sysv/linux/bits/types/siginfo_t.h:
New system-dependent bits headers.
* sysdeps/unix/sysv/linux/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/bits/siginfo-consts-arch.h
* sysdeps/unix/sysv/linux/ia64/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/ia64/bits/siginfo-consts-arch.h
* sysdeps/unix/sysv/linux/mips/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/sparc/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/tile/bits/siginfo-arch.h
* sysdeps/unix/sysv/linux/tile/bits/siginfo-consts-arch.h
* sysdeps/unix/sysv/linux/x86/bits/siginfo-arch.h:
New Linux-only system-dependent bits headers.
* signal/bits/types/sig_atomic_t.h
* signal/bits/types/sigset_t.h
* signal/bits/types/sigval_t.h:
New non-system-dependent bits headers.
* sysdeps/generic/sigsetops.h
* sysdeps/unix/sysv/linux/sigsetops.h:
New internal headers.
* include/bits/types/sig_atomic_t.h
* include/bits/types/sigset_t.h
* include/bits/types/sigval_t.h:
New wrappers.
* signal/sigsetops.h
* bits/siginfo.h
* bits/sigset.h
* sysdeps/unix/sysv/linux/bits/siginfo.h
* sysdeps/unix/sysv/linux/bits/sigset.h
* sysdeps/unix/sysv/linux/ia64/bits/siginfo.h
* sysdeps/unix/sysv/linux/mips/bits/siginfo.h
* sysdeps/unix/sysv/linux/s390/bits/siginfo.h
* sysdeps/unix/sysv/linux/sparc/bits/siginfo.h
* sysdeps/unix/sysv/linux/tile/bits/siginfo.h
* sysdeps/unix/sysv/linux/x86/bits/siginfo.h:
Deleted.
* signal/Makefile, sysdeps/unix/sysv/linux/Makefile:
Update lists of installed headers.
* posix/bits/types.h: Define __sig_atomic_t here.
* signal/signal.h: Use the new bits headers; no need to handle
__need_sig_atomic_t nor __need_sigset_t. Don't use __sigmask
to define sigmask.
* include/signal.h: No need to handle __need_sig_atomic_t
nor __need_sigset_t. Don't define __sigemptyset.
* io/sys/poll.h, setjmp/setjmp.h
* sysdeps/arm/sys/ucontext.h, sysdeps/generic/sys/ucontext.h
* sysdeps/i386/sys/ucontext.h, sysdeps/m68k/sys/ucontext.h
* sysdeps/mach/hurd/i386/bits/sigcontext.h
* sysdeps/mips/sys/ucontext.h, sysdeps/powerpc/novmxsetjmp.h
* sysdeps/pthread/bits/sigthread.h
* sysdeps/unix/sysv/linux/hppa/sys/ucontext.h
* sysdeps/unix/sysv/linux/m68k/sys/ucontext.h
* sysdeps/unix/sysv/linux/mips/sys/ucontext.h
* sysdeps/unix/sysv/linux/nios2/sys/ucontext.h
* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
* sysdeps/unix/sysv/linux/s390/sys/ucontext.h
* sysdeps/unix/sysv/linux/sh/sys/ucontext.h
* sysdeps/unix/sysv/linux/sparc/sys/ucontext.h
* sysdeps/unix/sysv/linux/tile/sys/ucontext.h
* sysdeps/unix/sysv/linux/x86/sys/ucontext.h:
Use bits/types/__sigset_t.h.
* misc/sys/select.h, posix/spawn.h
* sysdeps/unix/sysv/linux/powerpc/sys/ucontext.h
* sysdeps/unix/sysv/linux/sys/epoll.h
* sysdeps/unix/sysv/linux/sys/signalfd.h:
Use bits/types/sigset_t.h.
* resolv/netdb.h, rt/mqueue.h: Use bits/types/sigevent_t.h.
* rt/aio.h: Use bits/types/sigevent_t.h and bits/sigevent-consts.h.
* socket/sys/socket.h: Don't include bits/sigset.h.
* login/utmp_file.c, shadow/lckpwdf.c, signal/sigandset.c
* signal/sigisempty.c, stdlib/abort.c, sysdeps/posix/profil.c
* sysdeps/posix/sigignore.c, sysdeps/posix/sigintr.c
* sysdeps/posix/signal.c, sysdeps/posix/sigset.c
* sysdeps/posix/sprofil.c, sysdeps/posix/sysv_signal.c
* sysdeps/unix/sysv/linux/nptl-signals.h:
Include sigsetops.h.
* signal/sigaddset.c, signal/sigandset.c, signal/sigdelset.c
* signal/sigorset.c, stdlib/abort.c, sysdeps/posix/sigignore.c
* sysdeps/posix/signal.c, sysdeps/posix/sigset.c:
__sigaddset, __sigandset, __sigdelset, __sigemptyset, __sigorset
now return no value.
* signal/sigaddset.c, signal/sigdelset.c, signal/sigismem.c
Include <errno.h>, <signal.h>, and <sigsetops.h> instead of
"sigsetops.h".
* signal/sigsetops.c: Explicitly define __sigismember,
__sigaddset, and __sigdelset as compatibility symbols.
* signal/Versions: Correct commentary on __sigpause,
__sigaddset, __sigdelset, __sigismember.
* inet/rcmd.c: Include sigsetops.h. Convert old code using
__sigblock/__sigsetmask to use __sigprocmask and friends.
These __need macros are only used internally, by nptl/descr.h.
However, including all of resolv.h from descr.h causes build failures
due to resolv.h's dozens of pseudo-struct-field macros, some of which
collide with struct fields in NPTL internal data structures.
Similarly, including all of list.h from descr.h produces an include
cycle, atomic.h -> atomic-machine.h -> tls.h -> descr.h -> list.h ->
atomic.h, and then list.h tries to use atomic.h macros that haven't
been defined yet. So we do need mini-headers for these. In the
list.h case I called it include/list_t.h since it isn't going to be
installed.
* resolv/resolv.h: Remove __need_res_state logic.
Move definition of res_state and related constants to ...
* resolv/bits/types/res_state.h: ...this new file.
* resolv/Makefile: Install bits/types/res_state.h.
* include/bits/types/res_state.h: New wrapper.
* include/list.h: Remove __need_list_t logic.
Move definition of list_t to ...
* include/list_t.h: ...this new file.
* nptl/descr.h: Include list_t.h and bits/types/res_state.h
instead of list.h and resolv.h.
The address family splitting via format_ai_family made unpredictable
the place where the canonname field was printed. This commit adjusts
the implementation so that the ai_flags is checked for consistency
across the list, and ai_canonname must only be present on the first
list element.
Tests for AI_CANONNAME are added to resolv/tst-resolv-basic.
conform/ namespace tests of arpa/inet.h, netdb.h and netinet/in.h fail
for UNIX98 and XPG42 because of inclusion of stdint.h, which defines
macros not permitted in those headers for those standards. UNIX98
allows them to include inttypes.h, but (predating C99) has restricted
inttypes.h contents (not yet tested in the conform/ tests) not
including those macros; XPG4.2 has no such permission and no
inttypes.h / stdint.h at all.
This patch rearranges the headers to avoid this issue. intN_t
definitions move to bits/stdint-intn.h, and uintN_t definitions to
bits/stdint-uintn.h. (These are not bits/types/ headers because they
each define four types. They are separate rather than just a single
header because sys/types.h defines intN_t but u_intN_t rather than
uintN_t - and while sys/types.h could define uintN_t because of the
POSIX reservation of *_t, existing practice there is largely to
condition types on appropriate feature test macros, and indeed there
is at least one open bug report (14553) about a type that's not
so-conditioned, so maybe types there should actually have conditions
added where appropriate.) The affected network headers are then made
to include bits/stdint-uintn.h instead of stdint.h. This allows six
XFAILs to be removed.
This doesn't do anything about inttypes.h defining more than it should
for UNIX98, but we don't have conformtest expectations for that case
at present (and my inclination is that a fix for that should be as
local as possible - affecting only inttypes.h, not stdint.h, only for
the case of __USE_UNIX98 && !__USE_ISOC99).
Tested for x86_64.
[BZ #21455]
* bits/stdint-intn.h: New file.
* bits/stdint-uintn.h: Likewise.
* stdlib/Makefile (headers): Add bits/stdint-intn.h and
bits/stdint-uintn.h.
* inet/netinet/in.h: Include <bits/stdint-uintn.h> instead of
<stdint.h>.
* posix/sys/types.h: Include <bits/stdint-intn.h>.
(__int8_t_defined): Do not define here.
(int8_t): Likewise.
(int16_t): Likewise.
(int32_t): Likewise.
(int64_t): Likewise.
[__GNUC_PREREQ (2, 7)] (__intN_t): Likewise.
* resolv/netdb.h: Include <bits/stdint-uintn.h> instead of
<stdint.h>.
* include/netdb.h [_ISOMAC]: Do not include <stdint.h>.
* sysdeps/generic/stdint.h: Include <bits/stdint-intn.h> and
<bits/stdint-uintn.h>.
(int8_t): Do not define here.
(int16_t): Likewise.
(int32_t): Likewise.
(int64_t): Likewise.
(uint8_t): Likewise.
(uint16_t): Likewise.
(uint32_t): Likewise.
(uint64_t): Likewise.
* conform/Makefile (test-xfail-XPG42/arpa/inet.h/conform): Remove
variable.
(test-xfail-XPG42/netdb.h/conform): Likewise.
(test-xfail-XPG42/netinet/in.h/conform): Likewise.
(test-xfail-UNIX98/arpa/inet.h/conform): Likewise.
(test-xfail-UNIX98/netdb.h/conform): Likewise.
(test-xfail-UNIX98/netinet/in.h/conform): Likewise.
EDNS is disabled by default (so there is interoperability issue), and
the fallback code is problematic because it prevents an application
from obtaining DNSSEC data after a FORMERR response.
This bug did not affect name resolution because those functions
indirectly call ns_name_pack with a buffer which is always larger
than the generated query packet, even in the case of the
longest-possible domain name.
