Update userland arc4random() with OpenBSD's Chacha20 based arc4random().

  ObsoleteFiles.inc:

    Remove manual pages for arc4random_addrandom(3) and
    arc4random_stir(3).

  contrib/ntp/lib/isc/random.c:
  contrib/ntp/sntp/libevent/evutil_rand.c:

    Eliminate in-tree usage of arc4random_addrandom().

  crypto/heimdal/lib/roken/rand.c:
  crypto/openssh/config.h:

    Eliminate in-tree usage of arc4random_stir().

  include/stdlib.h:

    Remove arc4random_stir() and arc4random_addrandom() prototypes,
    provide temporary shims for transistion period.

  lib/libc/gen/Makefile.inc:

    Hook arc4random-compat.c to build, add hint for Chacha20 source for
    kernel, and remove arc4random_addrandom(3) and arc4random_stir(3)
    links.

  lib/libc/gen/arc4random.c:

    Adopt OpenBSD arc4random.c,v 1.54 with bare minimum changes, use the
    sys/crypto/chacha20 implementation of keystream.

  lib/libc/gen/Symbol.map:

    Remove arc4random_stir and arc4random_addrandom interfaces.

  lib/libc/gen/arc4random.h:

    Adopt OpenBSD arc4random.h,v 1.4 but provide _ARC4_LOCK of our own.

  lib/libc/gen/arc4random.3:

    Adopt OpenBSD arc4random.3,v 1.35 but keep FreeBSD r114444 and
    r118247.

  lib/libc/gen/arc4random-compat.c:

    Compatibility shims for arc4random_stir and arc4random_addrandom
    functions to preserve ABI.  Log once when called but do nothing
    otherwise.

  lib/libc/gen/getentropy.c:
  lib/libc/include/libc_private.h:

    Fold __arc4_sysctl into getentropy.c (renamed to arnd_sysctl).
    Remove from libc_private.h as a result.

  sys/crypto/chacha20/chacha.c:
  sys/crypto/chacha20/chacha.h:

    Make it possible to use the kernel implementation in libc.

PR:		182610
Reviewed by:	cem, markm
Obtained from:	OpenBSD
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D16760

1 files changed, 7 insertions, 2 deletions

diff --git a/include/stdlib.h b/include/stdlib.h
index d38952e15629..51f003171451 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -250,11 +250,16 @@ extern void (*malloc_message)(void *, const char *);
 void	 abort2(const char *, int, void **) __dead2;
 __uint32_t
 	 arc4random(void);
-void	 arc4random_addrandom(unsigned char *, int);
 void	 arc4random_buf(void *, size_t);
-void	 arc4random_stir(void);
 __uint32_t 
 	 arc4random_uniform(__uint32_t);
+
+#if !defined(BURN_BRIDGES)
+/* Deprecated arc4random() functions */
+#define arc4random_stir()
+#define arc4random_addrandom(a,b)
+#endif
+
 #ifdef __BLOCKS__
 int	 atexit_b(void (^ _Nonnull)(void));
 void	*bsearch_b(const void *, const void *, size_t,