rand/rand.c: Mix the pool key in `rand_gate' and `rand_stretch'.

[catacomb] / rand / rand.c

diff --git a/rand/rand.c b/rand/rand.c
index aa3fb45..6787c11 100644 (file)
--- a/rand/rand.c
+++ b/rand/rand.c
@@ -161,8 +161,26 @@ CPU_DISPATCH(static, return, int, quick, (rand_pool *r), (r),
 
 static int trivial_quick(rand_pool *r) { return (-1); }
 
+#if __GNUC__ && (CPUFAM_X86 || CPUFAM_AMD64)
+static int rdrand_quick(rand_pool *r)
+{
+  unsigned long rr;
+  int i = 16;
+
+  __asm__ ("0: rdrand %0; jc 9f; dec %1; jnz 0b; 9:"
+          : "=r" (rr), "=r" (i) : "1" (i) : "cc");
+  if (!i) return (-1);
+  rand_add(r, &rr, sizeof(rr), 8*sizeof(rr));
+  return (0);
+}
+#endif
+
 static quick__functype *pick_quick(void)
 {
+#if __GNUC__ && (CPUFAM_X86 || CPUFAM_AMD64)
+  DISPATCH_PICK_COND(rand_quick, rdrand_quick,
+                    cpu_feature_p(CPUFEAT_X86_RDRAND));
+#endif
   DISPATCH_PICK_FALLBACK(rand_quick, trivial_quick);
 }
 
@@ -305,6 +323,7 @@ void rand_gate(rand_pool *r)
 
   HASH_INIT(&hc);
   STORE32(g, r->gen); HASH(&hc, g, sizeof(g));
+  HASH(&hc, r->k.k, RAND_KEYSZ);
   HASH(&hc, r->pool, RAND_POOLSZ);
   HASH(&hc, r->buf, RAND_BUFSZ);
   HASH_DONE(&hc, h);
@@ -355,6 +374,7 @@ void rand_stretch(rand_pool *r)
 
   HASH_INIT(&hc);
   STORE32(g, r->gen); HASH(&hc, g, sizeof(g));
+  HASH(&hc, r->k.k, RAND_KEYSZ);
   HASH(&hc, r->pool, RAND_POOLSZ);
   HASH(&hc, r->buf, RAND_BUFSZ);
   HASH_DONE(&hc, h);