Change _rs_allocate so it can combine the two regions (rs and rsx)

into one if a system has an awesome getentropy().  In that case it
is valid to totally throw away the rsx state in the child.  If the
getentropy() is not very good and has a lazy reseed operation, this
combining is a bad idea, and the reseed should probably continue to
use the "something old, something new" mix.  _rs_allocate() can
accomodate either method, but not on the fly.
ok matthew

1 files changed, 14 insertions, 15 deletions

diff --git a/src/lib/libcrypto/crypto/arc4random_linux.h b/src/lib/libcrypto/crypto/arc4random_linux.h
index f02ae388d5..a713d15e06 100644
--- a/src/lib/libcrypto/crypto/arc4random_linux.h
+++ b/src/lib/libcrypto/crypto/arc4random_linux.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: arc4random_linux.h,v 1.2 2014/07/18 21:40:54 matthew Exp $    */
+/*      $OpenBSD: arc4random_linux.h,v 1.3 2014/07/19 00:08:43 deraadt Exp $    */
 
 /*
  * Copyright (c) 1996, David Mazieres <dm@uun.org>
@@ -22,15 +22,21 @@
  * Stub functions for portability.
  */
 
-static inline void *
-_rs_allocate(size_t len)
+static inline int
+_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
 {
-        void *p;
-
-        if ((p = mmap(NULL, len, PROT_READ|PROT_WRITE,
+        if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE,
             MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
-                return (NULL);
-        return (p);
+                return (-1);
+
+        if ((*rsxp = mmap(NULL, sizeof(**rsxp) PROT_READ|PROT_WRITE,
+            MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) {
+                munmap(*rsxp, sizeof(**rsxp);
+                return (-1);
+        }
+
+        _ARC4_ATFORK(_rs_forkhandler);
+        return (0);
 }
 
 static volatile sig_atomic_t _rs_forked;
@@ -54,10 +60,3 @@ _rs_forkdetect(void)
                         memset(rs, 0, sizeof(*rs));
         }
 }
-
-static inline void
-_rs_forkdetectsetup(struct _rs *rs, size_t len)
-{
-        _ARC4_ATFORK(_rs_forkhandler);
-}
-