glibc/sysdeps/generic/not-cancel.h

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Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
/* Uncancelable versions of cancelable interfaces. Generic version.
Copyright (C) 2003-2024 Free Software Foundation, Inc.
Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
Prefer https to http for gnu.org and fsf.org URLs Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 05:40:42 +00:00
<https://www.gnu.org/licenses/>. */
Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
#ifndef NOT_CANCEL_H
# define NOT_CANCEL_H
#include <fcntl.h>
arc4random: simplify design for better safety Rather than buffering 16 MiB of entropy in userspace (by way of chacha20), simply call getrandom() every time. This approach is doubtlessly slower, for now, but trying to prematurely optimize arc4random appears to be leading toward all sorts of nasty properties and gotchas. Instead, this patch takes a much more conservative approach. The interface is added as a basic loop wrapper around getrandom(), and then later, the kernel and libc together can work together on optimizing that. This prevents numerous issues in which userspace is unaware of when it really must throw away its buffer, since we avoid buffering all together. Future improvements may include userspace learning more from the kernel about when to do that, which might make these sorts of chacha20-based optimizations more possible. The current heuristic of 16 MiB is meaningless garbage that doesn't correspond to anything the kernel might know about. So for now, let's just do something conservative that we know is correct and won't lead to cryptographic issues for users of this function. This patch might be considered along the lines of, "optimization is the root of all evil," in that the much more complex implementation it replaces moves too fast without considering security implications, whereas the incremental approach done here is a much safer way of going about things. Once this lands, we can take our time in optimizing this properly using new interplay between the kernel and userspace. getrandom(0) is used, since that's the one that ensures the bytes returned are cryptographically secure. But on systems without it, we fallback to using /dev/urandom. This is unfortunate because it means opening a file descriptor, but there's not much of a choice. Secondly, as part of the fallback, in order to get more or less the same properties of getrandom(0), we poll on /dev/random, and if the poll succeeds at least once, then we assume the RNG is initialized. This is a rough approximation, as the ancient "non-blocking pool" initialized after the "blocking pool", not before, and it may not port back to all ancient kernels, though it does to all kernels supported by glibc (≥3.2), so generally it's the best approximation we can do. The motivation for including arc4random, in the first place, is to have source-level compatibility with existing code. That means this patch doesn't attempt to litigate the interface itself. It does, however, choose a conservative approach for implementing it. Cc: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: Cristian Rodríguez <crrodriguez@opensuse.org> Cc: Paul Eggert <eggert@cs.ucla.edu> Cc: Mark Harris <mark.hsj@gmail.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: linux-crypto@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2022-07-26 19:58:22 +00:00
#include <poll.h>
#include <unistd.h>
#include <sys/wait.h>
#include <time.h>
#include <sys/uio.h>
Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
/* By default we have none. Map the name to the normal functions. */
Consolidate non cancellable open call This patch consolidates all the non cancellable open calls to use the __open_nocancel identifier. For non cancellable targets it will be just a macro to call the default respective symbol while on Linux will be a internal one. To be consistent with the following non cancellable openat call, a new __open64_nocancel is also added (although not currently used). Checked on x86_64-linux-gnu, x86_64-linux-gnu-x32, and i686-linux-gnu. * sysdeps/generic/not-cancel.h (open_not_cancel): Remove macro. (open_not_cancel_2): Likewise. (open_nocancel): New macro. (open64_nocancel): Likewise. * sysdeps/unix/sysv/linux/not-cancel.h (open_not_cancel): Remove macro. (open_not_cancel_2): Likewise. (__open_nocancel): New prototype. (__open64_nocancel): Likewise. * sysdeps/unix/sysv/linux/Versions (libc) [GLIBC_PRIVATE]: Add __open_nocancel. * sysdeps/unix/sysv/linux/open.c (__open_nocancel): New function. * sysdeps/unix/sysv/linux/open64.c (__open64_nocancel): Likewise. * catgets/open_catalog.c (__open_catalog): Replace open_not_cancel{_2} with __open_nocancel. * csu/check_fds.c (check_one_fd): Likewise. * gmon/gmon.c (write_gmon): Likewise. * iconv/gconv_cache.c (__gconv_load_cached): Likewise. * intl/loadmsgcat.c (open): Likewise. * libio/fileops.c (_IO_file_open): Likewise. * locale/loadarchive.c (_nl_load_locale_from_archive): Likewise. * locale/loadlocale.c (_nl_load_locale): Likewise. * login/utmp_file.c (setutent_file): Likewise. * misc/daemon.c (daemon): Likewise. * nss/nss_db/db-open.c (internal_setent): Likewise. * sysdeps/mach/hurd/opendir.c (__opendirat): Likewise. * sysdeps/posix/libc_fatal.c (__libc_message): Likewise. * sysdeps/posix/opendir.c (tryopen_o_directory): Likewise. (__opendir): Likewise. * sysdeps/posix/spawni.c (__spawni_child): Likewise. * sysdeps/unix/sysv/linux/fips-private.h (fips_enable_p): Likewise. * sysdeps/unix/sysv/linux/gethostid.c (sethostid): Likewise. (gethostid): Likewise. * sysdeps/unix/sysv/linux/getloadavg.c (getloadavg): Likewise. * sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Likewise. * sysdeps/unix/sysv/linux/getsysstats.c (__get_nprocs): Likewise. * sysdeps/unix/sysv/linux/grantpt.c (__close_all_fds): Likewise. * sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system): Likewise. * sysdeps/unix/sysv/linux/ia64/has_cpuclock.c (has_cpuclock): Likewise. * sysdeps/unix/sysv/linux/libc_fatal.c (backtrace_and_maps): Likewise. * sysdeps/unix/sysv/linux/malloc-sysdep.h (check_may_shrink_heap): Likewise. * sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c (__get_clockfreq): Likewise. * sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np): Likewise. * sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np): Likewise. * sysdeps/unix/sysv/linux/spawni.c (__spawni_child): Likewise. * sysdeps/unix/sysv/linux/sysconf.c (__sysconf): Likewise.
2017-07-03 14:11:24 +00:00
#define __open_nocancel(...) \
__open (__VA_ARGS__)
#define __open64_nocancel(...) \
__open64 (__VA_ARGS__)
#define __openat_nocancel(...) \
__openat (__VA_ARGS__)
#define __openat64_nocancel(...) \
__openat64 (__VA_ARGS__)
Consolidate non cancellable close call This patch consolidates all the non cancellable close calls to use the __close_nocancel{_nostatus} identifier. For non cancellable targets it will be just a macro to call the default respective symbol while on Linux will be a internal one. Also, since it is used on libcrypto it is also exported in GLIBC_PRIVATE namespace. Checked on x86_64-linux-gnu, x86_64-linux-gnu-x32, and i686-linux-gnu. * sysdeps/generic/not-cancel.h (close_not_cancel): Remove macro. (close_not_cancel_no_status): Likewise. (__close_nocancel): New macro. (__close_nocancel_no_status): Likewise. * sysdeps/unix/sysv/linux/not-cancel.h (__close_nocancel): Remove macro. (close_not_cancel): Likewise. (close_not_cancel_no_status): Likewise. (__close_nocancel): New prototype. (__close_nocancel_no_status): New function. * sysdeps/unix/sysv/linux/close.c (__close_nocancel): New function. * catgets/open_catalog.c (__open_catalog): Replace close_not_cancel{_no_status) with __close_nocancel{_nostatus}. * gmon/gmon.c (write_gmon): Likewise. * iconv/gconv_cache.c (__gconv_load_cache): Likewise. * intl/loadmsgcat.c (close): Likewise. * io/ftw.c (open_dir_stream): Likewise. (ftw_startup): Likewise. * libio/fileops.c (_IO_file_open): Likewise. (_IO_file_close_mmap): Likewise. (_IO_file_close): Likewise. * libio/iopopen.c (_IO_dup2): Likewise. * locale/loadarchive.c (_nl_load_locale_from_archive): Likewise. * locale/loadlocale.c (_nl_load_locale): Likewise. * login/utmp_file.c (pututline_file): Likewise. (endutent_file): Likewise. * misc/daemon.c (daemon): Likewise. * nscd/nscd_getai.c (__nscd_getai): Likewise. * nscd/nscd_getgr_r.c (nscd_getgr_r): Likewise. * nscd/nscd_gethst_r.c (nscd_gethst_r): Likewise. * nscd/nscd_getpw_r.c (nscd_getpw_r): Likewise. * nscd/nscd_getserv_r.c (nscd_getserv_r): Likewise. * nscd/nscd_helper.c (open_socket): Likewise. (__nscd_open_socket): Likewise. * nscd/nscd_initgroups.c (__nscd_getgrouplist): Likewise. * nscd/nscd_netgroup.c (__nscd_setnetgrent): Likewise. (__nscd_innetgr): Likewise. * nss/nss_db/db-open.c (internal_setent): Likewise. * resolv/res-close.c (__res_iclose): Likewise. * sunrpc/pm_getmaps.c (pmap_getmaps): Likewise. * sysdeps/posix/closedir.c (__closedir): Likewise. * sysdeps/posix/getaddrinfo.c (getaddrinfo): Likewise. * sysdeps/posix/getcwd.c (__getcwd): Likewise. * sysdeps/posix/opendir.c (tryopen_o_directory): Likewise. (opendir_tail): Likewise. * sysdeps/posix/spawni.c (__spawni_child): Likewise. * sysdeps/unix/sysv/linux/check_native.c (__check_native): Likewise. * sysdeps/unix/sysv/linux/check_pf.c (__check_pf): Likewise. * sysdeps/unix/sysv/linux/fips-private.h (fips_enabled_p): Likewise. * sysdeps/unix/sysv/linux/gethostid.c (sethostid): Likewise. (gethostid): Likewise. * sysdeps/unix/sysv/linux/getloadavg.c (getloadavg): Likewise. * sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Likewise. * sysdeps/unix/sysv/linux/getsysstats.c (__get_nprocs): Likewise. * sysdeps/unix/sysv/linux/grantpt.c (close_all_fds): Likewise. * sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system): Likewise. * sysdeps/unix/sysv/linux/ia64/has_cpuclock.c (has_cpuclock): Likewise. * sysdeps/unix/sysv/linux/if_index.c (__if_nametoindex): Likewise. * sysdeps/unix/sysv/linux/libc_fatal.c (backtrace_and_maps): Likewise. * sysdeps/unix/sysv/linux/malloc-sysdep.h (check_may_shrink_heap): Likewise. * sysdeps/unix/sysv/linux/mq_notify.c (init_mq_netlink): Likewise. * sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np): Likewise. * sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np): Likewise. * sysdeps/unix/sysv/linux/spawni.c (__spawni_child): Likewise. * sysdeps/unix/sysv/linux/sysconf.c (__sysconf): Likewise.
2017-07-03 18:22:58 +00:00
#define __close_nocancel(fd) \
__close (fd)
Consolidate non cancellable close call This patch consolidates all the non cancellable close calls to use the __close_nocancel{_nostatus} identifier. For non cancellable targets it will be just a macro to call the default respective symbol while on Linux will be a internal one. Also, since it is used on libcrypto it is also exported in GLIBC_PRIVATE namespace. Checked on x86_64-linux-gnu, x86_64-linux-gnu-x32, and i686-linux-gnu. * sysdeps/generic/not-cancel.h (close_not_cancel): Remove macro. (close_not_cancel_no_status): Likewise. (__close_nocancel): New macro. (__close_nocancel_no_status): Likewise. * sysdeps/unix/sysv/linux/not-cancel.h (__close_nocancel): Remove macro. (close_not_cancel): Likewise. (close_not_cancel_no_status): Likewise. (__close_nocancel): New prototype. (__close_nocancel_no_status): New function. * sysdeps/unix/sysv/linux/close.c (__close_nocancel): New function. * catgets/open_catalog.c (__open_catalog): Replace close_not_cancel{_no_status) with __close_nocancel{_nostatus}. * gmon/gmon.c (write_gmon): Likewise. * iconv/gconv_cache.c (__gconv_load_cache): Likewise. * intl/loadmsgcat.c (close): Likewise. * io/ftw.c (open_dir_stream): Likewise. (ftw_startup): Likewise. * libio/fileops.c (_IO_file_open): Likewise. (_IO_file_close_mmap): Likewise. (_IO_file_close): Likewise. * libio/iopopen.c (_IO_dup2): Likewise. * locale/loadarchive.c (_nl_load_locale_from_archive): Likewise. * locale/loadlocale.c (_nl_load_locale): Likewise. * login/utmp_file.c (pututline_file): Likewise. (endutent_file): Likewise. * misc/daemon.c (daemon): Likewise. * nscd/nscd_getai.c (__nscd_getai): Likewise. * nscd/nscd_getgr_r.c (nscd_getgr_r): Likewise. * nscd/nscd_gethst_r.c (nscd_gethst_r): Likewise. * nscd/nscd_getpw_r.c (nscd_getpw_r): Likewise. * nscd/nscd_getserv_r.c (nscd_getserv_r): Likewise. * nscd/nscd_helper.c (open_socket): Likewise. (__nscd_open_socket): Likewise. * nscd/nscd_initgroups.c (__nscd_getgrouplist): Likewise. * nscd/nscd_netgroup.c (__nscd_setnetgrent): Likewise. (__nscd_innetgr): Likewise. * nss/nss_db/db-open.c (internal_setent): Likewise. * resolv/res-close.c (__res_iclose): Likewise. * sunrpc/pm_getmaps.c (pmap_getmaps): Likewise. * sysdeps/posix/closedir.c (__closedir): Likewise. * sysdeps/posix/getaddrinfo.c (getaddrinfo): Likewise. * sysdeps/posix/getcwd.c (__getcwd): Likewise. * sysdeps/posix/opendir.c (tryopen_o_directory): Likewise. (opendir_tail): Likewise. * sysdeps/posix/spawni.c (__spawni_child): Likewise. * sysdeps/unix/sysv/linux/check_native.c (__check_native): Likewise. * sysdeps/unix/sysv/linux/check_pf.c (__check_pf): Likewise. * sysdeps/unix/sysv/linux/fips-private.h (fips_enabled_p): Likewise. * sysdeps/unix/sysv/linux/gethostid.c (sethostid): Likewise. (gethostid): Likewise. * sysdeps/unix/sysv/linux/getloadavg.c (getloadavg): Likewise. * sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Likewise. * sysdeps/unix/sysv/linux/getsysstats.c (__get_nprocs): Likewise. * sysdeps/unix/sysv/linux/grantpt.c (close_all_fds): Likewise. * sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system): Likewise. * sysdeps/unix/sysv/linux/ia64/has_cpuclock.c (has_cpuclock): Likewise. * sysdeps/unix/sysv/linux/if_index.c (__if_nametoindex): Likewise. * sysdeps/unix/sysv/linux/libc_fatal.c (backtrace_and_maps): Likewise. * sysdeps/unix/sysv/linux/malloc-sysdep.h (check_may_shrink_heap): Likewise. * sysdeps/unix/sysv/linux/mq_notify.c (init_mq_netlink): Likewise. * sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np): Likewise. * sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np): Likewise. * sysdeps/unix/sysv/linux/spawni.c (__spawni_child): Likewise. * sysdeps/unix/sysv/linux/sysconf.c (__sysconf): Likewise.
2017-07-03 18:22:58 +00:00
#define __close_nocancel_nostatus(fd) \
Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
(void) __close (fd)
Consolidate non cancellable read call This patch consolidates all the non cancellable read calls to use the __read_nocancel identifier. For non cancellable targets it will be just a macro to call the default respective symbol while on Linux will be a internal one. Also, since it is used on libcrypto it is also exported in GLIBC_PRIVATE namespace. Checked on x86_64-linux-gnu, x86_64-linux-gnu-x32, and i686-linux-gnu. * sysdeps/generic/not-cancel.h (read_not_cancel): Remove macro. (__read_nocancel): New macro. * sysdeps/unix/sysv/linux/Versions (libc) [GLIBC_PRIVATE]: Add __read_nocancel. * sysdeps/unix/sysv/linux/not-cancel.h (__read_nocancel): Remove macro. (__read_nocancel): New prototype. * sysdeps/unix/sysv/linux/read.c (__read_nocancel): New function. * catgets/open_catalog.c (__open_catalog): Replace read_not_cancel with __read_nocancel. * intl/loadmsgcat.c (read): Likewise. * libio/fileops.c (_IO_file_read): Likewise. * locale/loadlocale.c (_nl_load_locale): Likewise. * login/utmp_file.c (getutent_r_file): Likewise. (internal_getut_r): Likewise. (getutline_r_file): Likewise. * sysdeps/unix/sysv/linux/fips-private.h (fips_enable_p): Likewise. * sysdeps/unix/sysv/linux/gethostid.c (gethostid): Likewise. * sysdeps/unix/sysv/linux/getloadavg.c (getloadavg): Likewise. * sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Likewise. * sysdeps/unix/sysv/linux/getsysstats.c (next_line): Likewise. * sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system): Likewise. * sysdeps/unix/sysv/linux/ia64/has_cpuclock.c (has_cpuclock): Likewise. * sysdeps/unix/sysv/linux/libc_fatal.c (backtrace_and_maps): Likewise. * sysdeps/unix/sysv/linux/malloc-sysdep.h (check_may_shrink_heap): Likewise. * sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np): Likewise. * sysdeps/unix/sysv/linux/sysconf.c (__sysconf): Likewise.
2017-07-03 17:20:46 +00:00
#define __read_nocancel(fd, buf, n) \
Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
__read (fd, buf, n)
#define __pread64_nocancel(fd, buf, count, offset) \
__pread64 (fd, buf, count, offset)
#define __write_nocancel(fd, buf, n) \
Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
__write (fd, buf, n)
#define __writev_nocancel_nostatus(fd, iov, n) \
Update. 2003-04-19 Ulrich Drepper <drepper@redhat.com> * catgets/nl_types.h: Remove __THROW marker from cancellation points. * dirent/dirent.h: Likewise. * dlfcn/dlfcn.h: Likewise. * grp/grp.h: Likewise. * iconv/iconv.h: Likewise. * io/fcntl.h: Likewise. * io/ftw.h: Likewise. * libio/stdio.h: Likewise. * misc/sys/mman.h: Likewise. * misc/sys/select.h: Likewise. * misc/sys/syslog.h: Likewise. * misc/sys/uio.h: Likewise. * posix/spawn.h: Likewise. * posix/unistd.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * rt/aio.h: Likewise. * shadow/shadow.h: Likewise. * signal/signal.h: Likewise. * socket/sys/socket.h: Likewise. * stdlib/stdlib.h: Likewise. * streams/stropts.h: Likewise. * string/string.h: Likewise. * sysdeps/gnu/utmpx.h: Likewise. * sysvipc/sys/msg.h: Likewise. * termios/termios.h: Likewise. * time/time.h: Likewise. * wcsmbs/wchar.h: Likewise. * iconv/gconv_cache.c: Include <not-cancel.h> and use non-cancelable functions. * misc/daemon.c: Likewise. * sysdeps/generic/backtracesymsfd.c: Likewise. * sysdeps/generic/check_fds.c: Likewise. * sysdeps/unix/sysv/linux/gethostid.c: Likewise. * sysdeps/unix/sysv/linux/not-cancel.h: New file. * sysdeps/generic/not-cancel.h: New file. * csu/Makefile (distribute): Add not-cancel.h. * sysdeps/unix/sysv/linux/fatal-prepare.h: New file. * sysdeps/unix/sysv/linux/Makefile: Define FATAL_PREPARE_INCLUDE for assert.c and assert-perr.c to include <fatal-prepare.h>. * sysdeps/unix/sysv/linux/Dist: Add fatal-prepare.h. * sysdeps/posix/remove.c (remove): Rewrite. No need to restore errno and unlink first. * io/ftw.c (ftw_dir): In all places assume fchdir is available. 2003-04-18 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/libc_fatal.c (__libc_fatal): Use INTERNAL_SYSCALL instead of INLINE_SYSCALL.
2003-04-19 16:57:17 +00:00
(void) __writev (fd, iov, n)
Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) This patch fixes the OFD ("file private") locks for architectures that support non-LFS flock definition (__USE_FILE_OFFSET64 not defined). The issue in this case is both F_OFD_{GETLK,SETLK,SETLKW} and F_{SET,GET}L{W}K64 expects a flock64 argument and when using old F_OFD_* flags with a non LFS flock argument the kernel might interpret the underlying data wrongly. Kernel idea originally was to avoid using such flags in non-LFS syscall, but since GLIBC uses fcntl with LFS semantic as default it is possible to provide the functionality and avoid the bogus struct kernel passing by adjusting the struct manually for the required flags. The idea follows other LFS interfaces that provide two symbols: 1. A new LFS fcntl64 is added on default ABI with the usual macros to select it for FILE_OFFSET_BITS=64. 2. The Linux non-LFS fcntl use a stack allocated struct flock64 for F_OFD_{GETLK,SETLK,SETLKW} copy the results on the user provided struct. 3. Keep a compat symbol with old broken semantic for architectures that do not define __OFF_T_MATCHES_OFF64_T. So for architectures which defines __USE_FILE_OFFSET64, fcntl64 will aliased to fcntl and no adjustment would be required. So to actually use F_OFD_* with LFS support the source must be built with LFS support (_FILE_OFFSET_BITS=64). Also F_OFD_SETLKW command is handled a cancellation point, as for F_SETLKW{64}. Checked on x86_64-linux-gnu and i686-linux-gnu. [BZ #20251] * NEWS: Mention fcntl64 addition. * csu/check_fds.c: Replace __fcntl_nocancel by __fcntl64_nocancel. * login/utmp_file.c: Likewise. * sysdeps/posix/fdopendir.c: Likewise. * sysdeps/posix/opendir.c: Likewise. * sysdeps/unix/pt-fcntl.c: Likewise. * include/fcntl.h (__libc_fcntl64, __fcntl64, __fcntl64_nocancel_adjusted): New prototype. (__fcntl_nocancel_adjusted): Remove prototype. * io/Makefile (routines): Add fcntl64. (CFLAGS-fcntl64.c): New rule. * io/Versions [GLIBC_2.28] (fcntl64): New symbol. [GLIBC_PRIVATE] (__libc_fcntl): Rename to __libc_fcntl64. * io/fcntl.h (fcntl64): Add prototype and redirect if __USE_FILE_OFFSET64 is defined. * io/fcntl64.c: New file. * manual/llio.text: Add a note for which commands fcntl acts a cancellation point. * nptl/Makefile (CFLAGS-fcntl64.c): New rule. * sysdeps/mach/hurd/fcntl.c: Alias fcntl to fcntl64 symbols. * sysdeps/mach/hurd/i386/libc.abilist [GLIBC_2.28] (fcntl, fcntl64): New symbols. * sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Fix F_GETLK64, F_OFD_GETLK, F_SETLK64, F_SETLKW64, F_OFD_SETLK, and F_OFD_SETLKW for non-LFS case. * sysdeps/unix/sysv/linux/fcntl64.c: New file. * sysdeps/unix/sysv/linux/fcntl_nocancel.c (__fcntl_nocancel): Rename to __fcntl64_nocancel. (__fcntl_nocancel_adjusted): Rename to __fcntl64_nocancel_adjusted. * sysdeps/unix/sysv/linux/not-cancel.h (__fcntl_nocancel): Rename to __fcntl64_nocancel. * sysdeps/unix/sysv/linux/tst-ofdlocks.c: New file. * sysdeps/unix/sysv/linux/tst-ofdlocks-compat.c: Likewise. * sysdeps/unix/sysv/linux/Makefile (tests): Add tst-ofdlocks. (tests-internal): Add tst-ofdlocks-compat. * sysdeps/unix/sysv/linux/aarch64/libc.abilist [GLIBC_2.28] (fcntl64): New symbol. * sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise. * sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/arm/libc.abilist [GLIBC_2.28] (fcntl, fcntl64): Likewise. * sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/i386/libc.abilis: Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
2018-04-04 14:24:15 +00:00
#define __fcntl64_nocancel(fd, cmd, ...) \
__fcntl64 (fd, cmd, __VA_ARGS__)
stdlib: Add arc4random, arc4random_buf, and arc4random_uniform (BZ #4417) The implementation is based on scalar Chacha20 with per-thread cache. It uses getrandom or /dev/urandom as fallback to get the initial entropy, and reseeds the internal state on every 16MB of consumed buffer. To improve performance and lower memory consumption the per-thread cache is allocated lazily on first arc4random functions call, and if the memory allocation fails getentropy or /dev/urandom is used as fallback. The cache is also cleared on thread exit iff it was initialized (so if arc4random is not called it is not touched). Although it is lock-free, arc4random is still not async-signal-safe (the per thread state is not updated atomically). The ChaCha20 implementation is based on RFC8439 [1], omitting the final XOR of the keystream with the plaintext because the plaintext is a stream of zeros. This strategy is similar to what OpenBSD arc4random does. The arc4random_uniform is based on previous work by Florian Weimer, where the algorithm is based on Jérémie Lumbroso paper Optimal Discrete Uniform Generation from Coin Flips, and Applications (2013) [2], who credits Donald E. Knuth and Andrew C. Yao, The complexity of nonuniform random number generation (1976), for solving the general case. The main advantage of this method is the that the unit of randomness is not the uniform random variable (uint32_t), but a random bit. It optimizes the internal buffer sampling by initially consuming a 32-bit random variable and then sampling byte per byte. Depending of the upper bound requested, it might lead to better CPU utilization. Checked on x86_64-linux-gnu, aarch64-linux, and powerpc64le-linux-gnu. Co-authored-by: Florian Weimer <fweimer@redhat.com> Reviewed-by: Yann Droneaud <ydroneaud@opteya.com> [1] https://datatracker.ietf.org/doc/html/rfc8439 [2] https://arxiv.org/pdf/1304.1916.pdf
2022-07-21 13:04:59 +00:00
#define __getrandom_nocancel(buf, size, flags) \
__getrandom (buf, size, flags)
#define __getrandom_nocancel_nostatus(buf, size, flags) \
__getrandom (buf, size, flags)
arc4random: simplify design for better safety Rather than buffering 16 MiB of entropy in userspace (by way of chacha20), simply call getrandom() every time. This approach is doubtlessly slower, for now, but trying to prematurely optimize arc4random appears to be leading toward all sorts of nasty properties and gotchas. Instead, this patch takes a much more conservative approach. The interface is added as a basic loop wrapper around getrandom(), and then later, the kernel and libc together can work together on optimizing that. This prevents numerous issues in which userspace is unaware of when it really must throw away its buffer, since we avoid buffering all together. Future improvements may include userspace learning more from the kernel about when to do that, which might make these sorts of chacha20-based optimizations more possible. The current heuristic of 16 MiB is meaningless garbage that doesn't correspond to anything the kernel might know about. So for now, let's just do something conservative that we know is correct and won't lead to cryptographic issues for users of this function. This patch might be considered along the lines of, "optimization is the root of all evil," in that the much more complex implementation it replaces moves too fast without considering security implications, whereas the incremental approach done here is a much safer way of going about things. Once this lands, we can take our time in optimizing this properly using new interplay between the kernel and userspace. getrandom(0) is used, since that's the one that ensures the bytes returned are cryptographically secure. But on systems without it, we fallback to using /dev/urandom. This is unfortunate because it means opening a file descriptor, but there's not much of a choice. Secondly, as part of the fallback, in order to get more or less the same properties of getrandom(0), we poll on /dev/random, and if the poll succeeds at least once, then we assume the RNG is initialized. This is a rough approximation, as the ancient "non-blocking pool" initialized after the "blocking pool", not before, and it may not port back to all ancient kernels, though it does to all kernels supported by glibc (≥3.2), so generally it's the best approximation we can do. The motivation for including arc4random, in the first place, is to have source-level compatibility with existing code. That means this patch doesn't attempt to litigate the interface itself. It does, however, choose a conservative approach for implementing it. Cc: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: Cristian Rodríguez <crrodriguez@opensuse.org> Cc: Paul Eggert <eggert@cs.ucla.edu> Cc: Mark Harris <mark.hsj@gmail.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: linux-crypto@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2022-07-26 19:58:22 +00:00
#define __poll_infinity_nocancel(fds, nfds) \
__poll (fds, nfds, -1)
#endif /* NOT_CANCEL_H */