This is a major rewrite of the description of 'crypt', 'getentropy',
and 'getrandom'.
A few highlights of the content changes:
- Throughout the manual, public headers, and user-visible messages,
I replaced the term "password" with "passphrase", the term
"password database" with "user database", and the term
"encrypt(ion)" with "(one-way) hashing" whenever it was applied to
passphrases. I didn't bother making this change in internal code
or tests. The use of the term "password" in ruserpass.c survives,
because that refers to a keyword in netrc files, but it is adjusted
to make this clearer.
There is a note in crypt.texi explaining that they were
traditionally called passwords but single words are not good enough
anymore, and a note in users.texi explaining that actual passphrase
hashes are found in a "shadow" database nowadays.
- There is a new short introduction to the "Cryptographic Functions"
section, explaining how we do not intend to be a general-purpose
cryptography library, and cautioning that there _are_, or have
been, legal restrictions on the use of cryptography in many
countries, without getting into any kind of detail that we can't
promise to keep up to date.
- I added more detail about what a "one-way function" is, and why
they are used to obscure passphrases for storage. I removed the
paragraph saying that systems not connected to a network need no
user authentication, because that's a pretty rare situation
nowadays. (It still says "sometimes it is necessary" to
authenticate the user, though.)
- I added documentation for all of the hash functions that glibc
actually supports, but not for the additional hash functions
supported by libxcrypt. If we're going to keep this manual section
around after the transition is more advanced, it would probably
make sense to add them then.
- There is much more detailed discussion of how to generate a salt,
and the failure behavior for crypt is documented. (Returning an
invalid hash on failure is what libxcrypt does; Solar Designer's
notes say that this was done "for compatibility with old programs
that assume crypt can never fail".)
- As far as I can tell, the header 'crypt.h' is entirely a GNU
invention, and never existed on any other Unix lineage. The
function 'crypt', however, was in Issue 1 of the SVID and is now
in the XSI component of POSIX. I tried to make all of the
@standards annotations consistent with this, but I'm not sure I got
them perfectly right.
- The genpass.c example has been improved to use getentropy instead
of the current time to generate the salt, and to use a SHA-256 hash
instead of MD5. It uses more random bytes than is strictly
necessary because I didn't want to complicate the code with proper
base64 encoding.
- The testpass.c example has three hardwired hashes now, to
demonstrate that different one-way functions produce different
hashes for the same input. It also demonstrates how DES hashing
only pays attention to the first eight characters of the input.
- There is new text explaining in more detail how a CSPRNG differs
from a regular random number generator, and how
getentropy/getrandom are not exactly a CSPRNG. I tried not to make
specific falsifiable claims here. I also tried to make the
blocking/cancellation/error behavior of both getentropy and
getrandom clearer.
In preparation for a major revision of the documentation for
crypt(_r), getentropy, and getrandom, reorganize crypt.texi. This
patch does not change any text; it only deletes and moves text.
The description of 'getpass' moves to terminal.texi, since all it does
is read a password from the controlling terminal with echo disabled.
The "Legal Problems" section of crypt.texi is dropped, and the
introductory text is shifted down to the "Encrypting Passwords"
section; the next patch will add some new introductory text.
Also, it is no longer true that crypt.texi's top @node needs to have
no pointers. That was a vestige of crypt/ being an add-on. (makeinfo
itself doesn't need @node pointers anymore, but the scripts that
assemble the libc manual's topmost node rely on each chapter-level
node having them.)
The functions encrypt, setkey, encrypt_r, setkey_r, cbc_crypt,
ecb_crypt, and des_setparity should not be used in new programs,
because they use the DES block cipher, which is unacceptably weak by
modern standards. Demote all of them to compatibility symbols, and
remove their prototypes from installed headers. cbc_crypt, ecb_crypt,
and des_setparity were already compat symbols when glibc was
configured with --disable-obsolete-rpc.
POSIX requires encrypt and setkey to be available when _XOPEN_CRYPT
is defined, so this change also removes the definition of X_OPEN_CRYPT
from <unistd.h>.
The entire "DES Encryption" section is dropped from the manual, as is
the mention of AUTH_DES and FIPS 140-2 in the introduction to
crypt.texi. The documentation of 'memfrob' cross-referenced the DES
Encryption section, which is replaced by a hyperlink to libgcrypt, and
while I was in there I spruced up the actual documentation of
'memfrob' and 'strfry' a little. It's still fairly jokey, because
those functions _are_ jokes, but they do also have real use cases, so
people trying to use them for real should have all the information
they need.
DES-based authentication for Sun RPC is also insecure and should be
deprecated or even removed, but maybe that can be left as TI-RPC's
problem.
A lookup operation in map_newlink could turn into an insert because of
holes in the interface part of the map. This leads to incorrectly set
the name of the interface to NULL when the interface is not present
for the address being processed (most likely because the interface was
added between the RTM_GETLINK and RTM_GETADDR calls to the kernel).
When such changes are detected by the kernel, it'll mark the dump as
"inconsistent" by setting NLM_F_DUMP_INTR flag on the next netlink
message.
This patch checks this condition and retries the whole operation.
Hopes are that next time the interface corresponding to the address
entry is present in the list and correct name is returned.
After commit d76d370355 ("Fix missing
timespec definition for sys/stat.h (BZ #21371)") in combination with
kernel UAPI changes, GCC sanitizer builds start to fail due to a
conflicting definition of struct timespec in <linux/time.h>. Use
_STRUCT_TIMESPEC as the header file inclusion guard, which is already
checked in the kernel header, to support including <linux/time.h> and
<sys/stat.h> in the same translation unit.
This patch adds __*ieee128 symbols for strfrom, strtold, strtold_l, wcstold
and wcstold_l functions. Redirection from *l to *ieee128 will be handled
in separate patch once we start building these new files.
2018-06-28 Rajalakshmi Srinivasaraghavan <raji@linux.vnet.ibm.com>
* sysdeps/ieee754/ldbl-128ibm-compat/Versions: Add __strfromieee128,
__strtoieee128, __strtoieee128_l,__wcstoieee128 and __wcstoieee128_l.
* sysdeps/ieee754/ldbl-128ibm-compat/strfromf128.c: New file.
* sysdeps/ieee754/ldbl-128ibm-compat/strtof128.c: New file.
* sysdeps/ieee754/ldbl-128ibm-compat/strtof128_l.c: New file.
* sysdeps/ieee754/ldbl-128ibm-compat/wcstof128.c: New file.
* sysdeps/ieee754/ldbl-128ibm-compat/wcstof128_l.c: New file.
Copy and null-terminate NIS+ password file UID and GID entries whose
length is non-zero and are not terminated, in addition to empty ones,
fixing a bug and a compilation issue causing an error with GCC 8:
nss_nisplus/nisplus-parser.c: In function '_nss_nisplus_parse_pwent':
nss_nisplus/nisplus-parser.c:90:7: error: 'strncpy' destination unchanged after copying no bytes [-Werror=stringop-truncation]
strncpy (first_unused, numstr, len);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
nss_nisplus/nisplus-parser.c:106:7: error: 'strncpy' destination unchanged after copying no bytes [-Werror=stringop-truncation]
strncpy (first_unused, numstr, len);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
introduced with commit ac05397075:
commit ac05397075
Author: Ulrich Drepper <drepper@redhat.com>
Date: Sun Apr 30 07:01:26 2006 +0000
* nis/nss_nisplus/nisplus-parser.c: Minor optimizations and
cleanups. Avoid copying data if it can be used in the old place.
(no mailing list reference available). Obviously regardless of the
recently added compiler diagnostics causing a build error this code has
been long non-functional, so I guess NIS+ servers have been supplying
strings that are non-empty and have already been null-terminated.
Which in turn made it unnecessary to make a null-terminated copy,
masking this bug.
[BZ #23266]
* nis/nss_nisplus/nisplus-parser.c (_nss_nisplus_parse_pwent):
Copy and null-terminate entries that are not terminated, in
addition to empty ones.
This patch removes nptl/sockperf.c, an unused, x86-specific program
with a hardcoded path in /tmp. If someone finds some of this code in
future for adding a proper benchmark, that does not of course rule out
adding it back in that form, but for now I think it's best to
eliminate this code with the hardcoded /tmp path.
Tested for x86_64.
* nptl/sockperf.c: Remove file.
The function comment suggests that _dl_map_object_deps cannot use
malloc, but it already allocates the l_initfini array on the heap, so
the additional allocation should be acceptable.
As noted in bug 13888, and as I noted previously in
<https://sourceware.org/ml/libc-alpha/2000-10/msg00111.html>, various
tests used hardcoded paths in /tmp, so posing issues for simultaneous
test runs from different build directories.
This patch fixes such uses of hardcoded file names to put them in the
build directory instead (in the case of stdio-common/bug5 the file
names are changed as well, to avoid a conflict with the name bug5.out
also used for the automatic test output redirection). It also fixes
test-installation.pl likewise (that was using filenames with $$ in
them rather than strictly hardcoded names, but that's still not good
practice for temporary file naming).
Note that my list of files changed is not identical to that in bug
13888. I added tst-spawn3.c and test-installation.pl, and removed
some tests that seem to me (now) to create temporary files securely
(simply using /tmp is not itself a problem if the temporary files are
handled properly with mkstemp; I haven't checked whether those tests
used to do things insecurely). conformtest is not changed because the
makefiles always pass a --tmpdir option so the /tmp default is
irrelevant, and for the same reason there is no actual problem with
nptl/tst-umask1.c because again the makefiles always override the
default.
nptl/sockperf.c is ignored because there is no code to run it;
probably that file should actually be removed.
Some tests use the mktemp function, but I think they all use it in a
way that *is* secure (for generating names for directories / sockets /
fifos / symlinks, where the operation using the name will not follow
symlinks and so there is no potential for a symlink attack on the
account running the testsuite).
Some tests use the tmpnam function to generate temporary file names.
This is in principle insecure, but not addressed by this patch (I
consider it a separate issue from the fully hardcoded paths).
Tested for x86_64.
[BZ #13888]
* posix/Makefile (CFLAGS-tst-spawn3.c): New variable.
* posix/tst-spawn3.c (do_test): Put tst-spwan3.pid in OBJPFX, not
/tmp.
* scripts/test-installation.pl: Put temporary files in build
directory, not /tmp.
* stdio-common/Makefile (CFLAGS-bug3.c): New variable.
(CFLAGS-bug4.c): Likewise.
(CFLAGS-bug5.c): Likewise.
(CFLAGS-test-fseek.c): Likewise.
(CFLAGS-test-popen.c): Likewise.
(CFLAGS-test_rdwr.c): Likewise.
* stdio-common/bug3.c (main): Put temporary file in OBJPFX, not
/tmp.
* stdio-common/bug4.c (main): Likewise.
* stdio-common/bug5.c (main): Likewise.
* stdio-common/test-fseek.c (TESTFILE): Likewise.
* stdio-common/test-popen.c (do_test): Likewise.
* stdio-common/test_rdwr.c (main): Likewise.
true. On some arches this caused valgrind to warn about uninitialized
bytes when the struct was written to the file system.
This patch moves the initialization of pad outside of the
conditional.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
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.
If the caller-supplied buffer is not large enough, fall back directly
malloc.
The previous __libc_use_alloca check was incorrect because it did not
take into account that extend_alloca may fail to merge allocations, so
it would underestimate the stack space being used by roughly a factor
of two.
The pre-allocation of the three scratch buffers increased the initial
stack size somewhat, but if retries are needed, the previous version
used more stack space if extend_alloca could not merge allocations.
Lack of alloca accounting also means could be problematic with
extremely large NSS responses, too.
[BZ #18023]
* nscd/aicache.c (addhstaiX): Use struct scratch_buffer instead
of extend_alloca.
Kashubian language is not supported by CLDR, data copied from Wikipedia
and documents released by RJK (official Kashubian Language Council),
also consulted with a native speaker.
Note that this language also needs ab_alt_mon feature due to the month
May: nominative "môj", genitive "maja"; abbreviated nominative "môj",
abbreviated genitive "maj".
[BZ #23140]
* localedata/locales/csb_PL (mon): Rename to...
(alt_mon): This.
(abmon): Rename to...
(ab_alt_mon): This.
(mon): Add with proper genitive forms, copy from Wikipedia.
(abmon): Likewise.
Thank you Michal Ostrowski for the feedback.
[BZ #19485]
* localedata/locales/csb_PL (mon): Fix typos:
"łżëkwiôt" -> "łżëkwiat" (April); "lëpinc" -> "lëpińc" (July).
(yesstr): Add, value is "jo".
(nostr): Add, value is "nié".
Commit 5e79e0292b broke m68k after
s_significand.c became available in the build directory. All m68k
implementations of log1p and significand were including s_significand.c
and stopped working after the inclusion of the the auto-generated file.
This patch reorganizes the implementation of log1p and significand for
m680x0 in order to avoid hitting this problem.
* sysdeps/m68k/m680x0/fpu/s_log1p.c: Set as the generic file for
all log1p and significand functions on m680x0.
* sysdeps/m68k/m680x0/fpu/s_log1pf.c: Include s_log1p.c instead
of s_significand.c..
* sysdeps/m68k/m680x0/fpu/s_log1pl.c: Likewise.
* sysdeps/m68k/m680x0/fpu/s_significandf.c: Likewise.
* sysdeps/m68k/m680x0/fpu/s_significandl.c: Likewise.
* sysdeps/m68k/m680x0/fpu/s_significand.c: Move all the code to
s_log1p.c and include it..
Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
The BPF ELF format has new relocation types R_BPF_64_64 and R_BPF_64_32.
The existing R_BPF_MAP_FD was an extension that never got implemented.
Remove it, because the constant conflicts with the official R_BPF_64_64.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Building the testsuite with GCC mainline fails with
-Wstringop-overflow= errors in string/tst-cmp.c. These are for calls
to strncmp and strncasecmp with SIZE_MAX size argument. The tests are
deliberately using this size that would be dubious in normal code, so
this patch disables the warning for the calls in question.
Tested with build-many-glibcs.py for aarch64-linux-gnu.
* string/tst-cmp.c: Include <libc-diag.h>.
(strncmp_max): Disable -Wstringop-overflow= around call to
strncmp.
(strncasecmp_max): Disable -Wstringop-overflow= around call to
strncasecmp.
Building the testsuite with GCC mainline fails with:
bug-strspn1.c: In function 'main':
bug-strspn1.c:14:3: error: right-hand operand of comma expression has no effect [-Werror=unused-value]
strspn (b++, "");
^~~~~~~~~~~~~~~~
and a similar error for bug-strpbrk1.c. I'm not sure what GCC change
introduced this, and the wording of the message is a bit off (in the
source it's not a comma expression, that must reflect GCC's IR). But
the warning is correct (strspn is a pure function, the call is
useless, and if there wasn't an argument with a side effect much older
GCC would have warned); the point of the test is to verify that the
side effect in an argument still occurs for this useless call that can
otherwise be optimized to an (unused) constant (testing for a bug
there once was in an old strspn macro). This patch duly arranges for
the warning to be disabled for this code.
Tested with build-many-glibcs.py for aarch64-linux-gnu.
* string/bug-strpbrk1.c: Include <libc-diag.h>.
(main): Disable -Wunused-value around call to strpbrk.
* string/bug-strspn1.c: Include <libc-diag.h>.
(main): Disable -Wunused-value around call to strspn.
Add a new libm-alias-float128.h in order to provide the __*ieee128
aliases for the existing *f128 that do not have a globally exported
symbol.
* sysdeps/ieee754/ldbl-128ibm-compat/Versions: New file.
* sysdeps/ieee754/ldbl-128ibm-compat/libm-alias-float128.h: New file.
Move declare_mgen_finite_alias, declare_mgen_finite_alias_s and
declare_mgen_finite_alias_x to a shared place in order to reuse them in
other files that also declare _finite aliases.
* math/e_exp2_template.c (declare_mgen_finite_alias,
declare_mgen_finite_alias_s, declare_mgen_finite_alias_x): Move to...
* sysdeps/generic/math-type-macros.h (declare_mgen_finite_alias,
declare_mgen_finite_alias_s, declare_mgen_finite_alias_x): ... here.
Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
As reported in bug 23280, scanf functions produce incorrectly rounded
result for floating-point formats in FE_UPWARD and FE_DOWNWARD modes,
because they pass the input with sign removed to strtod functions, and
then negate the result if there was a '-' at the start of the input.
This patch fixes this by arranging for the sign to be passed to strtod
rather than scanf doing the negation itself. In turn, keeping the
sign around in the buffer being built up for strtod requires updating
places that examine char_buffer_size (&charbuf) to allow for the sign
being there as an extra character.
Tested for x86_64.
[BZ #23280]
* stdio-common/vfscanf.c (_IO_vfscanf_internal): Pass sign of
floating-point number to strtod functions rather than possibly
negating result of those functions.
* stdio-common/tst-scanf-round.c: New file.
* stdio-common/Makefile (tests): Add tst-scanf-round.
($(objpfx)tst-scanf-round): Depend on $(libm).
This patch updates the hppa definition of MAP_TYPE to reflect a
corresponding change in the Linux kernel in 4.17 (so the value now has
four bits set, as it does on other architectures, although they are
different from other architectures because of hppa differences in
other MAP_* bits).
Tested with build-many-glibcs.py for hppa.
* sysdeps/unix/sysv/linux/hppa/bits/mman.h [__USE_MISC]
(MAP_TYPE): Change value to 0x2b.
