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-rw-r--r--src/shared/Makefile.am2
-rw-r--r--src/shared/hashmap.c1
-rw-r--r--src/shared/random-util.c127
-rw-r--r--src/shared/random-util.h38
-rw-r--r--src/shared/util.c114
-rw-r--r--src/shared/util.h5
6 files changed, 181 insertions, 106 deletions
diff --git a/src/shared/Makefile.am b/src/shared/Makefile.am
index 9f2df41e70..b0b4f59a6c 100644
--- a/src/shared/Makefile.am
+++ b/src/shared/Makefile.am
@@ -20,6 +20,7 @@ libudev_shared_la_SOURCES=\
MurmurHash2.c \
path-util.c \
process-util.c \
+ random-util.c \
selinux-util.c \
siphash24.c \
smack-util.c \
@@ -53,6 +54,7 @@ noinst_HEADERS = \
MurmurHash2.h \
path-util.h \
process-util.h \
+ random-util.h \
selinux-util.h \
set.h \
siphash24.h \
diff --git a/src/shared/hashmap.c b/src/shared/hashmap.c
index 084743e4fb..49bccacb5c 100644
--- a/src/shared/hashmap.c
+++ b/src/shared/hashmap.c
@@ -33,6 +33,7 @@
#include "strv.h"
#include "list.h"
#include "mempool.h"
+#include "random-util.h"
/*
* Implementation of hashmaps.
diff --git a/src/shared/random-util.c b/src/shared/random-util.c
new file mode 100644
index 0000000000..88f5182508
--- /dev/null
+++ b/src/shared/random-util.c
@@ -0,0 +1,127 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd 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.
+
+ systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdint.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <time.h>
+#include <sys/auxv.h>
+#include <linux/random.h>
+
+#include "random-util.h"
+#include "time-util.h"
+#include "missing.h"
+#include "util.h"
+
+int dev_urandom(void *p, size_t n) {
+ static int have_syscall = -1;
+
+ _cleanup_close_ int fd = -1;
+ int r;
+
+ /* Gathers some randomness from the kernel. This call will
+ * never block, and will always return some data from the
+ * kernel, regardless if the random pool is fully initialized
+ * or not. It thus makes no guarantee for the quality of the
+ * returned entropy, but is good enough for or usual usecases
+ * of seeding the hash functions for hashtable */
+
+ /* Use the getrandom() syscall unless we know we don't have
+ * it, or when the requested size is too large for it. */
+ if (have_syscall != 0 || (size_t) (int) n != n) {
+ r = getrandom(p, n, GRND_NONBLOCK);
+ if (r == (int) n) {
+ have_syscall = true;
+ return 0;
+ }
+
+ if (r < 0) {
+ if (errno == ENOSYS)
+ /* we lack the syscall, continue with
+ * reading from /dev/urandom */
+ have_syscall = false;
+ else if (errno == EAGAIN)
+ /* not enough entropy for now. Let's
+ * remember to use the syscall the
+ * next time, again, but also read
+ * from /dev/urandom for now, which
+ * doesn't care about the current
+ * amount of entropy. */
+ have_syscall = true;
+ else
+ return -errno;
+ } else
+ /* too short read? */
+ return -ENODATA;
+ }
+
+ fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY);
+ if (fd < 0)
+ return errno == ENOENT ? -ENOSYS : -errno;
+
+ return loop_read_exact(fd, p, n, true);
+}
+
+void initialize_srand(void) {
+ static bool srand_called = false;
+ unsigned x;
+#ifdef HAVE_SYS_AUXV_H
+ void *auxv;
+#endif
+
+ if (srand_called)
+ return;
+
+ x = 0;
+
+#ifdef HAVE_SYS_AUXV_H
+ /* The kernel provides us with a bit of entropy in auxv, so
+ * let's try to make use of that to seed the pseudo-random
+ * generator. It's better than nothing... */
+
+ auxv = (void*) getauxval(AT_RANDOM);
+ if (auxv)
+ x ^= *(unsigned*) auxv;
+#endif
+
+ x ^= (unsigned) now(CLOCK_REALTIME);
+ x ^= (unsigned) gettid();
+
+ srand(x);
+ srand_called = true;
+}
+
+void random_bytes(void *p, size_t n) {
+ uint8_t *q;
+ int r;
+
+ r = dev_urandom(p, n);
+ if (r >= 0)
+ return;
+
+ /* If some idiot made /dev/urandom unavailable to us, he'll
+ * get a PRNG instead. */
+
+ initialize_srand();
+
+ for (q = p; q < (uint8_t*) p + n; q ++)
+ *q = rand();
+}
diff --git a/src/shared/random-util.h b/src/shared/random-util.h
new file mode 100644
index 0000000000..f7862c8c8b
--- /dev/null
+++ b/src/shared/random-util.h
@@ -0,0 +1,38 @@
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd 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.
+
+ systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdint.h>
+
+int dev_urandom(void *p, size_t n);
+void random_bytes(void *p, size_t n);
+void initialize_srand(void);
+
+static inline uint64_t random_u64(void) {
+ uint64_t u;
+ random_bytes(&u, sizeof(u));
+ return u;
+}
+
+static inline uint32_t random_u32(void) {
+ uint32_t u;
+ random_bytes(&u, sizeof(u));
+ return u;
+}
diff --git a/src/shared/util.c b/src/shared/util.c
index d22ab8631f..0b04411f82 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -70,6 +70,7 @@
#include "fileio.h"
#include "virt.h"
#include "process-util.h"
+#include "random-util.h"
/* Put this test here for a lack of better place */
assert_cc(EAGAIN == EWOULDBLOCK);
@@ -719,6 +720,17 @@ ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) {
return n;
}
+int loop_read_exact(int fd, void *buf, size_t nbytes, bool do_poll) {
+ ssize_t n;
+
+ n = loop_read(fd, buf, nbytes, do_poll);
+ if (n < 0)
+ return n;
+ if ((size_t) n != nbytes)
+ return -EIO;
+ return 0;
+}
+
char* dirname_malloc(const char *path) {
char *d, *dir, *dir2;
@@ -737,108 +749,6 @@ char* dirname_malloc(const char *path) {
return dir;
}
-int dev_urandom(void *p, size_t n) {
- static int have_syscall = -1;
- int r, fd;
- ssize_t k;
-
- /* Gathers some randomness from the kernel. This call will
- * never block, and will always return some data from the
- * kernel, regardless if the random pool is fully initialized
- * or not. It thus makes no guarantee for the quality of the
- * returned entropy, but is good enough for or usual usecases
- * of seeding the hash functions for hashtable */
-
- /* Use the getrandom() syscall unless we know we don't have
- * it, or when the requested size is too large for it. */
- if (have_syscall != 0 || (size_t) (int) n != n) {
- r = getrandom(p, n, GRND_NONBLOCK);
- if (r == (int) n) {
- have_syscall = true;
- return 0;
- }
-
- if (r < 0) {
- if (errno == ENOSYS)
- /* we lack the syscall, continue with
- * reading from /dev/urandom */
- have_syscall = false;
- else if (errno == EAGAIN)
- /* not enough entropy for now. Let's
- * remember to use the syscall the
- * next time, again, but also read
- * from /dev/urandom for now, which
- * doesn't care about the current
- * amount of entropy. */
- have_syscall = true;
- else
- return -errno;
- } else
- /* too short read? */
- return -EIO;
- }
-
- fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY);
- if (fd < 0)
- return errno == ENOENT ? -ENOSYS : -errno;
-
- k = loop_read(fd, p, n, true);
- safe_close(fd);
-
- if (k < 0)
- return (int) k;
- if ((size_t) k != n)
- return -EIO;
-
- return 0;
-}
-
-void initialize_srand(void) {
- static bool srand_called = false;
- unsigned x;
-#ifdef HAVE_SYS_AUXV_H
- void *auxv;
-#endif
-
- if (srand_called)
- return;
-
- x = 0;
-
-#ifdef HAVE_SYS_AUXV_H
- /* The kernel provides us with a bit of entropy in auxv, so
- * let's try to make use of that to seed the pseudo-random
- * generator. It's better than nothing... */
-
- auxv = (void*) getauxval(AT_RANDOM);
- if (auxv)
- x ^= *(unsigned*) auxv;
-#endif
-
- x ^= (unsigned) now(CLOCK_REALTIME);
- x ^= (unsigned) gettid();
-
- srand(x);
- srand_called = true;
-}
-
-void random_bytes(void *p, size_t n) {
- uint8_t *q;
- int r;
-
- r = dev_urandom(p, n);
- if (r >= 0)
- return;
-
- /* If some idiot made /dev/urandom unavailable to us, he'll
- * get a PRNG instead. */
-
- initialize_srand();
-
- for (q = p; q < (uint8_t*) p + n; q ++)
- *q = rand();
-}
-
_pure_ static int is_temporary_fs(struct statfs *s) {
assert(s);
diff --git a/src/shared/util.h b/src/shared/util.h
index 0f97873d8b..c5e535069c 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -160,10 +160,6 @@ bool dirent_is_file_with_suffix(const struct dirent *de, const char *suffix) _pu
bool hidden_file(const char *filename) _pure_;
-int dev_urandom(void *p, size_t n);
-void random_bytes(void *p, size_t n);
-void initialize_srand(void);
-
/* For basic lookup tables with strictly enumerated entries */
#define _DEFINE_STRING_TABLE_LOOKUP_TO_STRING(name,type,scope) \
scope const char *name##_to_string(type i) { \
@@ -234,6 +230,7 @@ int flush_fd(int fd);
int fopen_temporary(const char *path, FILE **_f, char **_temp_path);
ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll);
+int loop_read_exact(int fd, void *buf, size_t nbytes, bool do_poll);
char* dirname_malloc(const char *path);
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-09 00:54:41 +0000