* [PATCH v2 0/2] tempname ALSR etc. fixes from Gnulib
@ 2022-08-25 21:46 Paul Eggert
2022-08-25 21:46 ` Paul Eggert
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: Paul Eggert @ 2022-08-25 21:46 UTC (permalink / raw)
To: libc-alpha; +Cc: Paul Eggert
This updates v1 as follows:
* It omits v1's first two patches as they have been installed into glibc already.
* It appends a patch to split __path_search into a separate file, as suggested by Bruno Haible on the Gnulib mailing list <https://lists.gnu.org/r/bug-gnulib/2022-08/msg00077.html> and now implemented in Gnulib <https://git.savannah.gnu.org/cgit/gnulib.git/commit/?id=044bf893acee0a55b22b4be0ede0e3ce010c480a>.
v2's first patch is identical to v1's third patch. v2's second patch is new.
Paul Eggert (2):
Merge tempname ASLR etc. patch from Gnulib
Split __path_search into a separate file
stdio-common/Makefile | 2 +
stdio-common/path-search.c | 31 +++++++
stdio-common/tempname.c | 14 ---
sysdeps/posix/path-search.c | 92 ++++++++++++++++++++
sysdeps/posix/tempname.c | 164 ++++++++++++------------------------
5 files changed, 178 insertions(+), 125 deletions(-)
create mode 100644 stdio-common/path-search.c
create mode 100644 sysdeps/posix/path-search.c
--
2.37.2
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 0/2] tempname ALSR etc. fixes from Gnulib
2022-08-25 21:46 [PATCH v2 0/2] tempname ALSR etc. fixes from Gnulib Paul Eggert
@ 2022-08-25 21:46 ` Paul Eggert
2022-08-25 21:46 ` [PATCH v2 1/2] Merge tempname ASLR etc. patch " Paul Eggert
2022-08-25 21:46 ` [PATCH v2 2/2] Split __path_search into a separate file Paul Eggert
2 siblings, 0 replies; 7+ messages in thread
From: Paul Eggert @ 2022-08-25 21:46 UTC (permalink / raw)
To: libc-alpha
This updates v1 as follows:
* It omits v1's first two patches as they have been installed into glibc already.
* It appends a patch to split __path_search into a separate file, as suggested by Bruno Haible on the Gnulib mailing list <https://lists.gnu.org/r/bug-gnulib/2022-08/msg00077.html> and now implemented in Gnulib <https://git.savannah.gnu.org/cgit/gnulib.git/commit/?id=044bf893acee0a55b22b4be0ede0e3ce010c480a>.
v2's first patch is identical to v1's third patch. v2's second patch is new.
Paul Eggert (2):
Merge tempname ASLR etc. patch from Gnulib
Split __path_search into a separate file
stdio-common/Makefile | 2 +
stdio-common/path-search.c | 31 +++++++
stdio-common/tempname.c | 14 ---
sysdeps/posix/path-search.c | 92 ++++++++++++++++++++
sysdeps/posix/tempname.c | 164 ++++++++++++------------------------
5 files changed, 178 insertions(+), 125 deletions(-)
create mode 100644 stdio-common/path-search.c
create mode 100644 sysdeps/posix/path-search.c
--
2.37.2
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 1/2] Merge tempname ASLR etc. patch from Gnulib
2022-08-25 21:46 [PATCH v2 0/2] tempname ALSR etc. fixes from Gnulib Paul Eggert
2022-08-25 21:46 ` Paul Eggert
@ 2022-08-25 21:46 ` Paul Eggert
2022-08-25 21:46 ` Paul Eggert
2022-08-25 21:46 ` [PATCH v2 2/2] Split __path_search into a separate file Paul Eggert
2 siblings, 1 reply; 7+ messages in thread
From: Paul Eggert @ 2022-08-25 21:46 UTC (permalink / raw)
To: libc-alpha; +Cc: Paul Eggert
Merge patch from Gnulib that fixes problems with ASLR info leak
and entropy loss. This syncs tempname.c with Gnulib commit
564b523fe97a8d63493aa68acb627b8c40744fb9 (2022-08-22) and
fixes <https://bugs.gnu.org/57129> which was reported against
Emacs and uncovered some unlikely Glibc bugs.
* sysdeps/posix/tempname.c: Don't include stdalign.h.
(mix_random_values): New function.
(random_bits): Use it. Args are now new value address and
old value, and this function now returns a success indicator.
Omit old USE_GETRANDOM argument: always try getrandom now, as
there is no good reason not to now that GRND_NONBLOCK is used.
Caller changed. Use CLOCK_REALTIME for for ersatz entropy,
as CLOCK_MONOTONIC doesn't work on some platforms.
Also, mix in ersatz entropy from tv_sec and from clock ().
(try_tempname_len): Do not mix in ASLR-based entropy, as
the result is published to the world and ASLR should be private.
Do not try to use a static var as that has issues if multithreaded.
Instead, simply generate new random bits.
Worry about bias only with high-quality random bits.
---
sysdeps/posix/tempname.c | 94 +++++++++++++++++++++++++---------------
1 file changed, 59 insertions(+), 35 deletions(-)
diff --git a/sysdeps/posix/tempname.c b/sysdeps/posix/tempname.c
index 60f8541085..0e2f29f5de 100644
--- a/sysdeps/posix/tempname.c
+++ b/sysdeps/posix/tempname.c
@@ -48,7 +48,6 @@
#include <string.h>
#include <fcntl.h>
-#include <stdalign.h>
#include <stdint.h>
#include <sys/random.h>
#include <sys/stat.h>
@@ -77,20 +76,55 @@ typedef uint_fast64_t random_value;
#define BASE_62_DIGITS 10 /* 62**10 < UINT_FAST64_MAX */
#define BASE_62_POWER (62LL * 62 * 62 * 62 * 62 * 62 * 62 * 62 * 62 * 62)
+/* Return the result of mixing the entropy from R and S.
+ Assume that R and S are not particularly random,
+ and that the result should look randomish to an untrained eye. */
+
static random_value
-random_bits (random_value var, bool use_getrandom)
+mix_random_values (random_value r, random_value s)
+{
+ /* As this code is used only when high-quality randomness is neither
+ available nor necessary, there is no need for fancier polynomials
+ such as those in the Linux kernel's 'random' driver. */
+ return (2862933555777941757 * r + 3037000493) ^ s;
+}
+
+/* Set *R to a random value.
+ Return true if *R is set to high-quality value taken from getrandom.
+ Otherwise return false, falling back to a low-quality *R that might
+ depend on S.
+
+ This function returns false only when getrandom fails.
+ On GNU systems this should happen only early in the boot process,
+ when the fallback should be good enough for programs using tempname
+ because any attacker likely has root privileges already. */
+
+static bool
+random_bits (random_value *r, random_value s)
{
- random_value r;
/* Without GRND_NONBLOCK it can be blocked for minutes on some systems. */
- if (use_getrandom && __getrandom (&r, sizeof r, GRND_NONBLOCK) == sizeof r)
- return r;
-#if _LIBC || (defined CLOCK_MONOTONIC && HAVE_CLOCK_GETTIME)
- /* Add entropy if getrandom did not work. */
+ if (__getrandom (r, sizeof *r, GRND_NONBLOCK) == sizeof *r)
+ return true;
+
+ /* If getrandom did not work, use ersatz entropy based on low-order
+ clock bits. On GNU systems getrandom should fail only
+ early in booting, when ersatz should be good enough.
+ Do not use ASLR-based entropy, as that would leak ASLR info into
+ the resulting file name which is typically public.
+
+ Of course we are in a state of sin here. */
+
+ random_value v = s;
+
+#if _LIBC || (defined CLOCK_REALTIME && HAVE_CLOCK_GETTIME)
struct __timespec64 tv;
- __clock_gettime64 (CLOCK_MONOTONIC, &tv);
- var ^= tv.tv_nsec;
+ __clock_gettime64 (CLOCK_REALTIME, &tv);
+ v = mix_random_values (v, tv.tv_sec);
+ v = mix_random_values (v, tv.tv_nsec);
#endif
- return 2862933555777941757 * var + 3037000493;
+
+ *r = mix_random_values (v, clock ());
+ return false;
}
#if _LIBC
@@ -213,7 +247,7 @@ static const char letters[] =
and return a read-write fd. The file is mode 0600.
__GT_DIR: create a directory, which will be mode 0700.
- We use a clever algorithm to get hard-to-predict names. */
+ */
#ifdef _LIBC
static
#endif
@@ -261,25 +295,17 @@ try_tempname_len (char *tmpl, int suffixlen, void *args,
unsigned int attempts = ATTEMPTS_MIN;
#endif
- /* A random variable. The initial value is used only the for fallback path
- on 'random_bits' on 'getrandom' failure. Its initial value tries to use
- some entropy from the ASLR and ignore possible bits from the stack
- alignment. */
- random_value v = ((uintptr_t) &v) / alignof (max_align_t);
+ /* A random variable. */
+ random_value v = 0;
- /* How many random base-62 digits can currently be extracted from V. */
+ /* A value derived from the random variable, and how many random
+ base-62 digits can currently be extracted from VDIGBUF. */
+ random_value vdigbuf;
int vdigits = 0;
- /* Whether to consume entropy when acquiring random bits. On the
- first try it's worth the entropy cost with __GT_NOCREATE, which
- is inherently insecure and can use the entropy to make it a bit
- less secure. On the (rare) second and later attempts it might
- help against DoS attacks. */
- bool use_getrandom = tryfunc == try_nocreate;
-
- /* Least unfair value for V. If V is less than this, V can generate
- BASE_62_DIGITS digits fairly. Otherwise it might be biased. */
- random_value const unfair_min
+ /* Least biased value for V. If V is less than this, V can generate
+ BASE_62_DIGITS unbiased digits. Otherwise the digits are biased. */
+ random_value const biased_min
= RANDOM_VALUE_MAX - RANDOM_VALUE_MAX % BASE_62_POWER;
len = strlen (tmpl);
@@ -299,18 +325,16 @@ try_tempname_len (char *tmpl, int suffixlen, void *args,
{
if (vdigits == 0)
{
- do
- {
- v = random_bits (v, use_getrandom);
- use_getrandom = true;
- }
- while (unfair_min <= v);
+ /* Worry about bias only if the bits are high quality. */
+ while (random_bits (&v, v) && biased_min <= v)
+ continue;
+ vdigbuf = v;
vdigits = BASE_62_DIGITS;
}
- XXXXXX[i] = letters[v % 62];
- v /= 62;
+ XXXXXX[i] = letters[vdigbuf % 62];
+ vdigbuf /= 62;
vdigits--;
}
--
2.37.2
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 1/2] Merge tempname ASLR etc. patch from Gnulib
2022-08-25 21:46 ` [PATCH v2 1/2] Merge tempname ASLR etc. patch " Paul Eggert
@ 2022-08-25 21:46 ` Paul Eggert
0 siblings, 0 replies; 7+ messages in thread
From: Paul Eggert @ 2022-08-25 21:46 UTC (permalink / raw)
To: libc-alpha
Merge patch from Gnulib that fixes problems with ASLR info leak
and entropy loss. This syncs tempname.c with Gnulib commit
564b523fe97a8d63493aa68acb627b8c40744fb9 (2022-08-22) and
fixes <https://bugs.gnu.org/57129> which was reported against
Emacs and uncovered some unlikely Glibc bugs.
* sysdeps/posix/tempname.c: Don't include stdalign.h.
(mix_random_values): New function.
(random_bits): Use it. Args are now new value address and
old value, and this function now returns a success indicator.
Omit old USE_GETRANDOM argument: always try getrandom now, as
there is no good reason not to now that GRND_NONBLOCK is used.
Caller changed. Use CLOCK_REALTIME for for ersatz entropy,
as CLOCK_MONOTONIC doesn't work on some platforms.
Also, mix in ersatz entropy from tv_sec and from clock ().
(try_tempname_len): Do not mix in ASLR-based entropy, as
the result is published to the world and ASLR should be private.
Do not try to use a static var as that has issues if multithreaded.
Instead, simply generate new random bits.
Worry about bias only with high-quality random bits.
---
sysdeps/posix/tempname.c | 94 +++++++++++++++++++++++++---------------
1 file changed, 59 insertions(+), 35 deletions(-)
diff --git a/sysdeps/posix/tempname.c b/sysdeps/posix/tempname.c
index 60f8541085..0e2f29f5de 100644
--- a/sysdeps/posix/tempname.c
+++ b/sysdeps/posix/tempname.c
@@ -48,7 +48,6 @@
#include <string.h>
#include <fcntl.h>
-#include <stdalign.h>
#include <stdint.h>
#include <sys/random.h>
#include <sys/stat.h>
@@ -77,20 +76,55 @@ typedef uint_fast64_t random_value;
#define BASE_62_DIGITS 10 /* 62**10 < UINT_FAST64_MAX */
#define BASE_62_POWER (62LL * 62 * 62 * 62 * 62 * 62 * 62 * 62 * 62 * 62)
+/* Return the result of mixing the entropy from R and S.
+ Assume that R and S are not particularly random,
+ and that the result should look randomish to an untrained eye. */
+
static random_value
-random_bits (random_value var, bool use_getrandom)
+mix_random_values (random_value r, random_value s)
+{
+ /* As this code is used only when high-quality randomness is neither
+ available nor necessary, there is no need for fancier polynomials
+ such as those in the Linux kernel's 'random' driver. */
+ return (2862933555777941757 * r + 3037000493) ^ s;
+}
+
+/* Set *R to a random value.
+ Return true if *R is set to high-quality value taken from getrandom.
+ Otherwise return false, falling back to a low-quality *R that might
+ depend on S.
+
+ This function returns false only when getrandom fails.
+ On GNU systems this should happen only early in the boot process,
+ when the fallback should be good enough for programs using tempname
+ because any attacker likely has root privileges already. */
+
+static bool
+random_bits (random_value *r, random_value s)
{
- random_value r;
/* Without GRND_NONBLOCK it can be blocked for minutes on some systems. */
- if (use_getrandom && __getrandom (&r, sizeof r, GRND_NONBLOCK) == sizeof r)
- return r;
-#if _LIBC || (defined CLOCK_MONOTONIC && HAVE_CLOCK_GETTIME)
- /* Add entropy if getrandom did not work. */
+ if (__getrandom (r, sizeof *r, GRND_NONBLOCK) == sizeof *r)
+ return true;
+
+ /* If getrandom did not work, use ersatz entropy based on low-order
+ clock bits. On GNU systems getrandom should fail only
+ early in booting, when ersatz should be good enough.
+ Do not use ASLR-based entropy, as that would leak ASLR info into
+ the resulting file name which is typically public.
+
+ Of course we are in a state of sin here. */
+
+ random_value v = s;
+
+#if _LIBC || (defined CLOCK_REALTIME && HAVE_CLOCK_GETTIME)
struct __timespec64 tv;
- __clock_gettime64 (CLOCK_MONOTONIC, &tv);
- var ^= tv.tv_nsec;
+ __clock_gettime64 (CLOCK_REALTIME, &tv);
+ v = mix_random_values (v, tv.tv_sec);
+ v = mix_random_values (v, tv.tv_nsec);
#endif
- return 2862933555777941757 * var + 3037000493;
+
+ *r = mix_random_values (v, clock ());
+ return false;
}
#if _LIBC
@@ -213,7 +247,7 @@ static const char letters[] =
and return a read-write fd. The file is mode 0600.
__GT_DIR: create a directory, which will be mode 0700.
- We use a clever algorithm to get hard-to-predict names. */
+ */
#ifdef _LIBC
static
#endif
@@ -261,25 +295,17 @@ try_tempname_len (char *tmpl, int suffixlen, void *args,
unsigned int attempts = ATTEMPTS_MIN;
#endif
- /* A random variable. The initial value is used only the for fallback path
- on 'random_bits' on 'getrandom' failure. Its initial value tries to use
- some entropy from the ASLR and ignore possible bits from the stack
- alignment. */
- random_value v = ((uintptr_t) &v) / alignof (max_align_t);
+ /* A random variable. */
+ random_value v = 0;
- /* How many random base-62 digits can currently be extracted from V. */
+ /* A value derived from the random variable, and how many random
+ base-62 digits can currently be extracted from VDIGBUF. */
+ random_value vdigbuf;
int vdigits = 0;
- /* Whether to consume entropy when acquiring random bits. On the
- first try it's worth the entropy cost with __GT_NOCREATE, which
- is inherently insecure and can use the entropy to make it a bit
- less secure. On the (rare) second and later attempts it might
- help against DoS attacks. */
- bool use_getrandom = tryfunc == try_nocreate;
-
- /* Least unfair value for V. If V is less than this, V can generate
- BASE_62_DIGITS digits fairly. Otherwise it might be biased. */
- random_value const unfair_min
+ /* Least biased value for V. If V is less than this, V can generate
+ BASE_62_DIGITS unbiased digits. Otherwise the digits are biased. */
+ random_value const biased_min
= RANDOM_VALUE_MAX - RANDOM_VALUE_MAX % BASE_62_POWER;
len = strlen (tmpl);
@@ -299,18 +325,16 @@ try_tempname_len (char *tmpl, int suffixlen, void *args,
{
if (vdigits == 0)
{
- do
- {
- v = random_bits (v, use_getrandom);
- use_getrandom = true;
- }
- while (unfair_min <= v);
+ /* Worry about bias only if the bits are high quality. */
+ while (random_bits (&v, v) && biased_min <= v)
+ continue;
+ vdigbuf = v;
vdigits = BASE_62_DIGITS;
}
- XXXXXX[i] = letters[v % 62];
- v /= 62;
+ XXXXXX[i] = letters[vdigbuf % 62];
+ vdigbuf /= 62;
vdigits--;
}
--
2.37.2
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 2/2] Split __path_search into a separate file
2022-08-25 21:46 [PATCH v2 0/2] tempname ALSR etc. fixes from Gnulib Paul Eggert
2022-08-25 21:46 ` Paul Eggert
2022-08-25 21:46 ` [PATCH v2 1/2] Merge tempname ASLR etc. patch " Paul Eggert
@ 2022-08-25 21:46 ` Paul Eggert
2022-08-25 21:46 ` Paul Eggert
2022-08-26 9:47 ` Florian Weimer
2 siblings, 2 replies; 7+ messages in thread
From: Paul Eggert @ 2022-08-25 21:46 UTC (permalink / raw)
To: libc-alpha; +Cc: Paul Eggert
This simplifies sharing tempname with Gnulib.
Suggested by Bruno Haible in:
https://lists.gnu.org/r/bug-gnulib/2022-08/msg00077.html
* stdio-common/Makefile (routines): Add path-search.
(CFLAGS-path-search.c): New macro, which has -fexceptions
because tempname.c has it.
* stdio-common/path-search.c, sysdeps/posix/path-search.c:
New files.
* stdio-common/tempname.c (__need_size_t): Do not define.
No need to include stddef.h, since stdio.h declares size_t.
(__path_search): Move to path-search.c.
* sysdeps/posix/tempname.c:
Don't include sys/types.h, assert.h, stddef.h; not needed.
(P_tmpdir): Remove.
(__secure_getenv) [_LIBC]: Remove.
(__stat64) [!_LIBC]: Remove.
(direxists, __path_search) [_LIBC]: Move to path-search.c.
---
stdio-common/Makefile | 2 +
stdio-common/path-search.c | 31 +++++++++++++
stdio-common/tempname.c | 14 ------
sysdeps/posix/path-search.c | 92 +++++++++++++++++++++++++++++++++++++
sysdeps/posix/tempname.c | 82 ---------------------------------
5 files changed, 125 insertions(+), 96 deletions(-)
create mode 100644 stdio-common/path-search.c
create mode 100644 sysdeps/posix/path-search.c
diff --git a/stdio-common/Makefile b/stdio-common/Makefile
index b1e9144de0..1543b5414b 100644
--- a/stdio-common/Makefile
+++ b/stdio-common/Makefile
@@ -49,6 +49,7 @@ routines := \
itoa-digits \
itoa-udigits \
itowa-digits \
+ path-search \
perror \
printf \
printf-prs \
@@ -351,6 +352,7 @@ $(objpfx)tst-errno-manual.out: tst-errno-manual.py \
CFLAGS-vfprintf.c += -Wno-uninitialized
CFLAGS-vfwprintf.c += -Wno-uninitialized
+CFLAGS-path-search.c += -fexceptions
CFLAGS-tmpfile.c += -fexceptions
CFLAGS-tmpfile64.c += -fexceptions
CFLAGS-tempname.c += -fexceptions
diff --git a/stdio-common/path-search.c b/stdio-common/path-search.c
new file mode 100644
index 0000000000..6ad7002d7c
--- /dev/null
+++ b/stdio-common/path-search.c
@@ -0,0 +1,31 @@
+/* Copyright (C) 1991-2022 Free Software Foundation, Inc.
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <stdio.h>
+#include <errno.h>
+
+/* Perform the "SVID path search malarkey" on DIR and PFX. Write a
+ template suitable for use in __gen_tempname into TMPL, bounded
+ by TMPL_LEN. */
+int
+__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
+ int try_tmpdir)
+{
+ __set_errno (ENOSYS);
+ return -1;
+}
+stub_warning (__path_search)
diff --git a/stdio-common/tempname.c b/stdio-common/tempname.c
index 621876a9d9..6538fb1777 100644
--- a/stdio-common/tempname.c
+++ b/stdio-common/tempname.c
@@ -15,23 +15,9 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#define __need_size_t
-#include <stddef.h>
#include <stdio.h>
#include <errno.h>
-/* Perform the "SVID path search malarkey" on DIR and PFX. Write a
- template suitable for use in __gen_tempname into TMPL, bounded
- by TMPL_LEN. */
-int
-__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
- int try_tmpdir)
-{
- __set_errno (ENOSYS);
- return -1;
-}
-stub_warning (__path_search)
-
/* Generate a (hopefully) unique temporary filename
in DIR (if applicable), using template TMPL.
KIND determines what to do with that name. It may be one of:
diff --git a/sysdeps/posix/path-search.c b/sysdeps/posix/path-search.c
new file mode 100644
index 0000000000..ae2f404f58
--- /dev/null
+++ b/sysdeps/posix/path-search.c
@@ -0,0 +1,92 @@
+/* Copyright (C) 1991-2022 Free Software Foundation, Inc.
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+
+/* Return nonzero if DIR is an existent directory. */
+static int
+direxists (const char *dir)
+{
+ struct __stat64_t64 buf;
+ return __stat64_time64 (dir, &buf) == 0 && S_ISDIR (buf.st_mode);
+}
+
+/* Path search algorithm, for tmpnam, tmpfile, etc. If DIR is
+ non-null and exists, uses it; otherwise uses the first of $TMPDIR,
+ P_tmpdir, /tmp that exists. Copies into TMPL a template suitable
+ for use with mk[s]temp. Will fail (-1) if DIR is non-null and
+ doesn't exist, none of the searched dirs exists, or there's not
+ enough space in TMPL. */
+int
+__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
+ int try_tmpdir)
+{
+ const char *d;
+ size_t dlen, plen;
+
+ if (!pfx || !pfx[0])
+ {
+ pfx = "file";
+ plen = 4;
+ }
+ else
+ {
+ plen = strlen (pfx);
+ if (plen > 5)
+ plen = 5;
+ }
+
+ if (try_tmpdir)
+ {
+ d = __libc_secure_getenv ("TMPDIR");
+ if (d != NULL && direxists (d))
+ dir = d;
+ else if (dir != NULL && direxists (dir))
+ /* nothing */ ;
+ else
+ dir = NULL;
+ }
+ if (dir == NULL)
+ {
+ if (direxists (P_tmpdir))
+ dir = P_tmpdir;
+ else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp"))
+ dir = "/tmp";
+ else
+ {
+ __set_errno (ENOENT);
+ return -1;
+ }
+ }
+
+ dlen = strlen (dir);
+ while (dlen > 1 && dir[dlen - 1] == '/')
+ dlen--; /* remove trailing slashes */
+
+ /* check we have room for "${dir}/${pfx}XXXXXX\0" */
+ if (tmpl_len < dlen + 1 + plen + 6 + 1)
+ {
+ __set_errno (EINVAL);
+ return -1;
+ }
+
+ sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx);
+ return 0;
+}
diff --git a/sysdeps/posix/tempname.c b/sysdeps/posix/tempname.c
index 0e2f29f5de..11b4796b34 100644
--- a/sysdeps/posix/tempname.c
+++ b/sysdeps/posix/tempname.c
@@ -20,16 +20,10 @@
# include "tempname.h"
#endif
-#include <sys/types.h>
-#include <assert.h>
#include <stdbool.h>
-
#include <errno.h>
#include <stdio.h>
-#ifndef P_tmpdir
-# define P_tmpdir "/tmp"
-#endif
#ifndef TMP_MAX
# define TMP_MAX 238328
#endif
@@ -43,7 +37,6 @@
# error report this to bug-gnulib@gnu.org
#endif
-#include <stddef.h>
#include <stdlib.h>
#include <string.h>
@@ -55,14 +48,12 @@
#if _LIBC
# define struct_stat64 struct __stat64_t64
-# define __secure_getenv __libc_secure_getenv
#else
# define struct_stat64 struct stat
# define __gen_tempname gen_tempname
# define __mkdir mkdir
# define __open open
# define __lstat64_time64(file, buf) lstat (file, buf)
-# define __stat64(file, buf) stat (file, buf)
# define __getrandom getrandom
# define __clock_gettime64 clock_gettime
# define __timespec64 timespec
@@ -127,79 +118,6 @@ random_bits (random_value *r, random_value s)
return false;
}
-#if _LIBC
-/* Return nonzero if DIR is an existent directory. */
-static int
-direxists (const char *dir)
-{
- struct_stat64 buf;
- return __stat64_time64 (dir, &buf) == 0 && S_ISDIR (buf.st_mode);
-}
-
-/* Path search algorithm, for tmpnam, tmpfile, etc. If DIR is
- non-null and exists, uses it; otherwise uses the first of $TMPDIR,
- P_tmpdir, /tmp that exists. Copies into TMPL a template suitable
- for use with mk[s]temp. Will fail (-1) if DIR is non-null and
- doesn't exist, none of the searched dirs exists, or there's not
- enough space in TMPL. */
-int
-__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
- int try_tmpdir)
-{
- const char *d;
- size_t dlen, plen;
-
- if (!pfx || !pfx[0])
- {
- pfx = "file";
- plen = 4;
- }
- else
- {
- plen = strlen (pfx);
- if (plen > 5)
- plen = 5;
- }
-
- if (try_tmpdir)
- {
- d = __secure_getenv ("TMPDIR");
- if (d != NULL && direxists (d))
- dir = d;
- else if (dir != NULL && direxists (dir))
- /* nothing */ ;
- else
- dir = NULL;
- }
- if (dir == NULL)
- {
- if (direxists (P_tmpdir))
- dir = P_tmpdir;
- else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp"))
- dir = "/tmp";
- else
- {
- __set_errno (ENOENT);
- return -1;
- }
- }
-
- dlen = strlen (dir);
- while (dlen > 1 && dir[dlen - 1] == '/')
- dlen--; /* remove trailing slashes */
-
- /* check we have room for "${dir}/${pfx}XXXXXX\0" */
- if (tmpl_len < dlen + 1 + plen + 6 + 1)
- {
- __set_errno (EINVAL);
- return -1;
- }
-
- sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx);
- return 0;
-}
-#endif /* _LIBC */
-
#if _LIBC
static int try_tempname_len (char *, int, void *, int (*) (char *, void *),
size_t);
--
2.37.2
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 2/2] Split __path_search into a separate file
2022-08-25 21:46 ` [PATCH v2 2/2] Split __path_search into a separate file Paul Eggert
@ 2022-08-25 21:46 ` Paul Eggert
2022-08-26 9:47 ` Florian Weimer
1 sibling, 0 replies; 7+ messages in thread
From: Paul Eggert @ 2022-08-25 21:46 UTC (permalink / raw)
To: libc-alpha
This simplifies sharing tempname with Gnulib.
Suggested by Bruno Haible in:
https://lists.gnu.org/r/bug-gnulib/2022-08/msg00077.html
* stdio-common/Makefile (routines): Add path-search.
(CFLAGS-path-search.c): New macro, which has -fexceptions
because tempname.c has it.
* stdio-common/path-search.c, sysdeps/posix/path-search.c:
New files.
* stdio-common/tempname.c (__need_size_t): Do not define.
No need to include stddef.h, since stdio.h declares size_t.
(__path_search): Move to path-search.c.
* sysdeps/posix/tempname.c:
Don't include sys/types.h, assert.h, stddef.h; not needed.
(P_tmpdir): Remove.
(__secure_getenv) [_LIBC]: Remove.
(__stat64) [!_LIBC]: Remove.
(direxists, __path_search) [_LIBC]: Move to path-search.c.
---
stdio-common/Makefile | 2 +
stdio-common/path-search.c | 31 +++++++++++++
stdio-common/tempname.c | 14 ------
sysdeps/posix/path-search.c | 92 +++++++++++++++++++++++++++++++++++++
sysdeps/posix/tempname.c | 82 ---------------------------------
5 files changed, 125 insertions(+), 96 deletions(-)
create mode 100644 stdio-common/path-search.c
create mode 100644 sysdeps/posix/path-search.c
diff --git a/stdio-common/Makefile b/stdio-common/Makefile
index b1e9144de0..1543b5414b 100644
--- a/stdio-common/Makefile
+++ b/stdio-common/Makefile
@@ -49,6 +49,7 @@ routines := \
itoa-digits \
itoa-udigits \
itowa-digits \
+ path-search \
perror \
printf \
printf-prs \
@@ -351,6 +352,7 @@ $(objpfx)tst-errno-manual.out: tst-errno-manual.py \
CFLAGS-vfprintf.c += -Wno-uninitialized
CFLAGS-vfwprintf.c += -Wno-uninitialized
+CFLAGS-path-search.c += -fexceptions
CFLAGS-tmpfile.c += -fexceptions
CFLAGS-tmpfile64.c += -fexceptions
CFLAGS-tempname.c += -fexceptions
diff --git a/stdio-common/path-search.c b/stdio-common/path-search.c
new file mode 100644
index 0000000000..6ad7002d7c
--- /dev/null
+++ b/stdio-common/path-search.c
@@ -0,0 +1,31 @@
+/* Copyright (C) 1991-2022 Free Software Foundation, Inc.
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <stdio.h>
+#include <errno.h>
+
+/* Perform the "SVID path search malarkey" on DIR and PFX. Write a
+ template suitable for use in __gen_tempname into TMPL, bounded
+ by TMPL_LEN. */
+int
+__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
+ int try_tmpdir)
+{
+ __set_errno (ENOSYS);
+ return -1;
+}
+stub_warning (__path_search)
diff --git a/stdio-common/tempname.c b/stdio-common/tempname.c
index 621876a9d9..6538fb1777 100644
--- a/stdio-common/tempname.c
+++ b/stdio-common/tempname.c
@@ -15,23 +15,9 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#define __need_size_t
-#include <stddef.h>
#include <stdio.h>
#include <errno.h>
-/* Perform the "SVID path search malarkey" on DIR and PFX. Write a
- template suitable for use in __gen_tempname into TMPL, bounded
- by TMPL_LEN. */
-int
-__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
- int try_tmpdir)
-{
- __set_errno (ENOSYS);
- return -1;
-}
-stub_warning (__path_search)
-
/* Generate a (hopefully) unique temporary filename
in DIR (if applicable), using template TMPL.
KIND determines what to do with that name. It may be one of:
diff --git a/sysdeps/posix/path-search.c b/sysdeps/posix/path-search.c
new file mode 100644
index 0000000000..ae2f404f58
--- /dev/null
+++ b/sysdeps/posix/path-search.c
@@ -0,0 +1,92 @@
+/* Copyright (C) 1991-2022 Free Software Foundation, Inc.
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+
+/* Return nonzero if DIR is an existent directory. */
+static int
+direxists (const char *dir)
+{
+ struct __stat64_t64 buf;
+ return __stat64_time64 (dir, &buf) == 0 && S_ISDIR (buf.st_mode);
+}
+
+/* Path search algorithm, for tmpnam, tmpfile, etc. If DIR is
+ non-null and exists, uses it; otherwise uses the first of $TMPDIR,
+ P_tmpdir, /tmp that exists. Copies into TMPL a template suitable
+ for use with mk[s]temp. Will fail (-1) if DIR is non-null and
+ doesn't exist, none of the searched dirs exists, or there's not
+ enough space in TMPL. */
+int
+__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
+ int try_tmpdir)
+{
+ const char *d;
+ size_t dlen, plen;
+
+ if (!pfx || !pfx[0])
+ {
+ pfx = "file";
+ plen = 4;
+ }
+ else
+ {
+ plen = strlen (pfx);
+ if (plen > 5)
+ plen = 5;
+ }
+
+ if (try_tmpdir)
+ {
+ d = __libc_secure_getenv ("TMPDIR");
+ if (d != NULL && direxists (d))
+ dir = d;
+ else if (dir != NULL && direxists (dir))
+ /* nothing */ ;
+ else
+ dir = NULL;
+ }
+ if (dir == NULL)
+ {
+ if (direxists (P_tmpdir))
+ dir = P_tmpdir;
+ else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp"))
+ dir = "/tmp";
+ else
+ {
+ __set_errno (ENOENT);
+ return -1;
+ }
+ }
+
+ dlen = strlen (dir);
+ while (dlen > 1 && dir[dlen - 1] == '/')
+ dlen--; /* remove trailing slashes */
+
+ /* check we have room for "${dir}/${pfx}XXXXXX\0" */
+ if (tmpl_len < dlen + 1 + plen + 6 + 1)
+ {
+ __set_errno (EINVAL);
+ return -1;
+ }
+
+ sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx);
+ return 0;
+}
diff --git a/sysdeps/posix/tempname.c b/sysdeps/posix/tempname.c
index 0e2f29f5de..11b4796b34 100644
--- a/sysdeps/posix/tempname.c
+++ b/sysdeps/posix/tempname.c
@@ -20,16 +20,10 @@
# include "tempname.h"
#endif
-#include <sys/types.h>
-#include <assert.h>
#include <stdbool.h>
-
#include <errno.h>
#include <stdio.h>
-#ifndef P_tmpdir
-# define P_tmpdir "/tmp"
-#endif
#ifndef TMP_MAX
# define TMP_MAX 238328
#endif
@@ -43,7 +37,6 @@
# error report this to bug-gnulib@gnu.org
#endif
-#include <stddef.h>
#include <stdlib.h>
#include <string.h>
@@ -55,14 +48,12 @@
#if _LIBC
# define struct_stat64 struct __stat64_t64
-# define __secure_getenv __libc_secure_getenv
#else
# define struct_stat64 struct stat
# define __gen_tempname gen_tempname
# define __mkdir mkdir
# define __open open
# define __lstat64_time64(file, buf) lstat (file, buf)
-# define __stat64(file, buf) stat (file, buf)
# define __getrandom getrandom
# define __clock_gettime64 clock_gettime
# define __timespec64 timespec
@@ -127,79 +118,6 @@ random_bits (random_value *r, random_value s)
return false;
}
-#if _LIBC
-/* Return nonzero if DIR is an existent directory. */
-static int
-direxists (const char *dir)
-{
- struct_stat64 buf;
- return __stat64_time64 (dir, &buf) == 0 && S_ISDIR (buf.st_mode);
-}
-
-/* Path search algorithm, for tmpnam, tmpfile, etc. If DIR is
- non-null and exists, uses it; otherwise uses the first of $TMPDIR,
- P_tmpdir, /tmp that exists. Copies into TMPL a template suitable
- for use with mk[s]temp. Will fail (-1) if DIR is non-null and
- doesn't exist, none of the searched dirs exists, or there's not
- enough space in TMPL. */
-int
-__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
- int try_tmpdir)
-{
- const char *d;
- size_t dlen, plen;
-
- if (!pfx || !pfx[0])
- {
- pfx = "file";
- plen = 4;
- }
- else
- {
- plen = strlen (pfx);
- if (plen > 5)
- plen = 5;
- }
-
- if (try_tmpdir)
- {
- d = __secure_getenv ("TMPDIR");
- if (d != NULL && direxists (d))
- dir = d;
- else if (dir != NULL && direxists (dir))
- /* nothing */ ;
- else
- dir = NULL;
- }
- if (dir == NULL)
- {
- if (direxists (P_tmpdir))
- dir = P_tmpdir;
- else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp"))
- dir = "/tmp";
- else
- {
- __set_errno (ENOENT);
- return -1;
- }
- }
-
- dlen = strlen (dir);
- while (dlen > 1 && dir[dlen - 1] == '/')
- dlen--; /* remove trailing slashes */
-
- /* check we have room for "${dir}/${pfx}XXXXXX\0" */
- if (tmpl_len < dlen + 1 + plen + 6 + 1)
- {
- __set_errno (EINVAL);
- return -1;
- }
-
- sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx);
- return 0;
-}
-#endif /* _LIBC */
-
#if _LIBC
static int try_tempname_len (char *, int, void *, int (*) (char *, void *),
size_t);
--
2.37.2
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v2 2/2] Split __path_search into a separate file
2022-08-25 21:46 ` [PATCH v2 2/2] Split __path_search into a separate file Paul Eggert
2022-08-25 21:46 ` Paul Eggert
@ 2022-08-26 9:47 ` Florian Weimer
1 sibling, 0 replies; 7+ messages in thread
From: Florian Weimer @ 2022-08-26 9:47 UTC (permalink / raw)
To: Paul Eggert; +Cc: libc-alpha
* Paul Eggert:
> This simplifies sharing tempname with Gnulib.
> Suggested by Bruno Haible in:
> https://lists.gnu.org/r/bug-gnulib/2022-08/msg00077.html
> * stdio-common/Makefile (routines): Add path-search.
> (CFLAGS-path-search.c): New macro, which has -fexceptions
> because tempname.c has it.
> * stdio-common/path-search.c, sysdeps/posix/path-search.c:
> New files.
> * stdio-common/tempname.c (__need_size_t): Do not define.
> No need to include stddef.h, since stdio.h declares size_t.
> (__path_search): Move to path-search.c.
> * sysdeps/posix/tempname.c:
> Don't include sys/types.h, assert.h, stddef.h; not needed.
> (P_tmpdir): Remove.
> (__secure_getenv) [_LIBC]: Remove.
> (__stat64) [!_LIBC]: Remove.
> (direxists, __path_search) [_LIBC]: Move to path-search.c.
sysdeps/posix/path-search.c is not intended to be shared with gnulib,
right? Change looks okay to me.
Thanks,
Florian
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2022-08-26 9:47 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-08-25 21:46 [PATCH v2 0/2] tempname ALSR etc. fixes from Gnulib Paul Eggert
2022-08-25 21:46 ` Paul Eggert
2022-08-25 21:46 ` [PATCH v2 1/2] Merge tempname ASLR etc. patch " Paul Eggert
2022-08-25 21:46 ` Paul Eggert
2022-08-25 21:46 ` [PATCH v2 2/2] Split __path_search into a separate file Paul Eggert
2022-08-25 21:46 ` Paul Eggert
2022-08-26 9:47 ` Florian Weimer
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