Always use compat getentropy.

Have it call native getentropy and fall back as required.  Should fix
issues of platforms where libc has getentropy but it is not implemented
in the kernel.  Based on github PR#354 from simsergey.

diff --git a/openbsd-compat/arc4random.c b/openbsd-compat/arc4random.c
index 02f15f9c3bfad9baaf30615d7bbfc4d631e3c86b..ffd33734db5647250745b06a6b0afa7f886055c5 100644 (file)
--- a/openbsd-compat/arc4random.c
+++ b/openbsd-compat/arc4random.c
@@ -44,13 +44,15 @@
 #ifndef HAVE_ARC4RANDOM
 
 /*
- * If we're not using a native getentropy, use the one from bsd-getentropy.c
- * under a different name, so that if in future these binaries are run on
- * a system that has a native getentropy OpenSSL cannot call the wrong one.
+ * Always use the getentropy implementation from bsd-getentropy.c, which
+ * will call a native getentropy if available then fall back as required.
+ * We use a different name so that OpenSSL cannot call the wrong getentropy.
  */
-#ifndef HAVE_GETENTROPY
-# define getentropy(x, y) (_ssh_compat_getentropy((x), (y)))
+int _ssh_compat_getentropy(void *, size_t);
+#ifdef getentropy
+# undef getentropy
 #endif
+#define getentropy(x, y) (_ssh_compat_getentropy((x), (y)))
 
 #include "log.h"
 

diff --git a/openbsd-compat/bsd-getentropy.c b/openbsd-compat/bsd-getentropy.c
index bd4b6695acc6f038a435801c6dd902f77eee6596..554dfad70524ce6eeb492d02e8ce18809c7d58ae 100644 (file)
--- a/openbsd-compat/bsd-getentropy.c
+++ b/openbsd-compat/bsd-getentropy.c
@@ -18,8 +18,6 @@
 
 #include "includes.h"
 
-#ifndef HAVE_GETENTROPY
-
 #ifndef SSH_RANDOM_DEV
 # define SSH_RANDOM_DEV "/dev/urandom"
 #endif /* SSH_RANDOM_DEV */
@@ -52,6 +50,10 @@ _ssh_compat_getentropy(void *s, size_t len)
        ssize_t r;
        size_t o = 0;
 
+#ifdef HAVE_GETENTROPY
+       if (r = getentropy(s, len) == 0)
+               return 0;
+#endif /* HAVE_GETENTROPY */
 #ifdef HAVE_GETRANDOM
        if ((r = getrandom(s, len, 0)) > 0 && (size_t)r == len)
                return 0;
@@ -79,4 +81,3 @@ _ssh_compat_getentropy(void *s, size_t len)
 #endif /* WITH_OPENSSL */
        return 0;
 }
-#endif /* WITH_GETENTROPY */

diff --git a/openbsd-compat/openbsd-compat.h b/openbsd-compat/openbsd-compat.h
index 4af207cdd40f63d244f84f85deb8af1280cb9687..8f8150905c15c546e20119284ba71e34a21ebd1a 100644 (file)
--- a/openbsd-compat/openbsd-compat.h
+++ b/openbsd-compat/openbsd-compat.h
@@ -69,10 +69,6 @@ void closefrom(int);
 int ftruncate(int filedes, off_t length);
 #endif
 
-#if defined(HAVE_DECL_GETENTROPY) && HAVE_DECL_GETENTROPY == 0
-int _ssh_compat_getentropy(void *, size_t);
-#endif
-
 #ifndef HAVE_GETLINE
 #include <stdio.h>
 ssize_t getline(char **, size_t *, FILE *);