factotum/libressl-portable
1
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

override native arc4random_buf on FreeBSD

Browse Source 
The FreeBSD-native arc4random_buf implementation falls back to weak
sources of entropy if the sysctl fails. Remove these dangerous fallbacks
by overriding locally.

Unfortunately, pthread_atfork() is broken on FreeBSD (at least 9 and 10)
if a program does not link to -lthr. Callbacks registered with
pthread_atfork() simply fail silently. So, it is not always possible to
detect a PID wraparound. I wish we could do better.

This improves arc4random_buf's safety compared to the native FreeBSD
implementation. Tested on FreeBSD 9 and 10.

ok beck@ deraadt@
This commit is contained in:
Brent Cook 2014-10-27 19:22:03 -05:00
parent 8abf8e1e15
commit 0aeb93b9fc
5 changed files with 19 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
apps/Makefile.am.tpl
View File

@ -3,7 +3,7 @@ include $(top_srcdir)/Makefile.am.common
bin_PROGRAMS = openssl
openssl_CFLAGS = $(USER_CFLAGS)
openssl_LDADD = $(PLATFORM_LDADD)
openssl_LDADD = $(PLATFORM_LDADD) $(PROG_LDADD)
openssl_LDADD += $(top_builddir)/ssl/libssl.la
openssl_LDADD += $(top_builddir)/crypto/libcrypto.la

7
configure.ac
View File

@ -13,6 +13,10 @@ case $host_os in
HOST_OS=darwin;
LDFLAGS="$LDFLAGS -Qunused-arguments"
;;
*freebsd*)
HOST_OS=freebsd;
AC_SUBST([PROG_LDADD], ['-lthr'])
;;
*linux*)
HOST_OS=linux;
CFLAGS="$CFLAGS -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_POSIX_SOURCE -D_GNU_SOURCE"
@ -33,6 +37,7 @@ case $host_os in
esac
AM_CONDITIONAL(HOST_DARWIN, test x$HOST_OS = xdarwin)
AM_CONDITIONAL(HOST_FREEBSD, test x$HOST_OS = xfreebsd)
AM_CONDITIONAL(HOST_LINUX, test x$HOST_OS = xlinux)
AM_CONDITIONAL(HOST_SOLARIS, test x$HOST_OS = xsolaris)
AM_CONDITIONAL(HOST_WIN, test x$HOST_OS = xwin)
@ -81,7 +86,7 @@ AM_CONDITIONAL([HAVE_TIMINGSAFE_MEMCMP], [test "x$ac_cv_func_timingsafe_memcmp"
# overrides for arc4random_buf implementations with known issues
AM_CONDITIONAL([HAVE_ARC4RANDOM_BUF],
[test "x$HOST_OS" != xdarwin -a "x$NO_ARC4RANDOM_BUF" = xtrue])
[test "x$HOST_OS" != xdarwin -a "x$HOST_OS" != xfreebsd -a "x$ac_cv_func_arc4random_buf" = xyes])
AC_CACHE_CHECK([whether va_copy exists], ac_cv_have_va_copy, [
AC_LINK_IFELSE([AC_LANG_PROGRAM([[

4
crypto/Makefile.am.tpl
View File

@ -61,6 +61,9 @@ if !HAVE_ARC4RANDOM_BUF
libcompat_la_SOURCES += compat/arc4random.c
if !HAVE_GETENTROPY
if HOST_FREEBSD
libcompat_la_SOURCES += compat/getentropy_freebsd.c
endif
if HOST_LINUX
libcompat_la_SOURCES += compat/getentropy_linux.c
endif
@ -88,6 +91,7 @@ endif
noinst_HEADERS = des/ncbc_enc.c
noinst_HEADERS += compat/arc4random.h
noinst_HEADERS += compat/arc4random_freebsd.h
noinst_HEADERS += compat/arc4random_linux.h
noinst_HEADERS += compat/arc4random_osx.h
noinst_HEADERS += compat/arc4random_solaris.h

7
crypto/compat/arc4random.h
View File

@ -1,7 +1,12 @@
#ifndef LIBCRYPTOCOMPAT_ARC4RANDOM_H
#define LIBCRYPTOCOMPAT_ARC4RANDOM_H
#if defined(__linux__)
#include <sys/param.h>
#if defined(__FreeBSD__)
#include "arc4random_freebsd.h"
#elif defined(__linux__)
#include "arc4random_linux.h"
#elif defined(__APPLE__)

3
tests/Makefile.am.tpl
View File

@ -3,7 +3,8 @@ include $(top_srcdir)/Makefile.am.common
AM_CPPFLAGS += -I $(top_srcdir)/crypto/modes
AM_CPPFLAGS += -I $(top_srcdir)/crypto/asn1
LDADD = $(top_builddir)/ssl/libssl.la
LDADD = $(PLATFORM_LDADD) $(PROG_LDADD)
LDADD += $(top_builddir)/ssl/libssl.la
LDADD += $(top_builddir)/crypto/libcrypto.la
TESTS =