X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fbasic%2Frandom-util.c;h=ad7b3eedf2c1d5ffb7ca92662bff43e070878872;hb=0f58036abf34e92313105839658420e95acfdd7e;hp=b230044f50994a12070c3a842c18563148211438;hpb=3b22396a4b2767a98172f6915929c47738cb0a1e;p=elogind.git
diff --git a/src/basic/random-util.c b/src/basic/random-util.c
index b230044f5..ad7b3eedf 100644
--- a/src/basic/random-util.c
+++ b/src/basic/random-util.c
@@ -17,21 +17,24 @@
along with systemd; If not, see .
***/
-#include
+#include
#include
-#include
-#include
#include
-#include
+#include
+#include
+#include
+#include
+#include
+
#ifdef HAVE_SYS_AUXV_H
#include
#endif
-#include
+#include "fd-util.h"
+#include "io-util.h"
+#include "missing.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;
@@ -43,7 +46,7 @@ int dev_urandom(void *p, size_t n) {
* 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
+ * returned entropy, but is good enough for our usual usecases
* of seeding the hash functions for hashtable */
/* Use the getrandom() syscall unless we know we don't have
@@ -92,17 +95,18 @@ void initialize_srand(void) {
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... */
+ /* The kernel provides us with 16 bytes 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;
+ if (auxv) {
+ assert_cc(sizeof(x) < 16);
+ memcpy(&x, auxv, sizeof(x));
+ } else
#endif
+ x = 0;
+
x ^= (unsigned) now(CLOCK_REALTIME);
x ^= (unsigned) gettid();