diff options
author | Damien Miller <djm@mindrot.org> | 2011-06-23 08:30:03 +1000 |
---|---|---|
committer | Damien Miller <djm@mindrot.org> | 2011-06-23 08:30:03 +1000 |
commit | 69ff1df952eebf0489b775a60ede094eaf596a05 (patch) | |
tree | 6eb76b4632b7c131e0fbb52d8ce7cccf658b6bfa /configure.ac | |
parent | 82c558761d0fa42dc954d62812b9e4b4a94f64bd (diff) |
- djm@cvs.openbsd.org 2011/06/22 21:57:01
[servconf.c servconf.h sshd.c sshd_config.5 sandbox-rlimit.c]
[sandbox-systrace.c sandbox.h configure.ac Makefile.in]
introduce sandboxing of the pre-auth privsep child using systrace(4).
This introduces a new "UsePrivilegeSeparation=sandbox" option for
sshd_config that applies mandatory restrictions on the syscalls the
privsep child can perform. This prevents a compromised privsep child
from being used to attack other hosts (by opening sockets and proxying)
or probing local kernel attack surface.
The sandbox is implemented using systrace(4) in unsupervised "fast-path"
mode, where a list of permitted syscalls is supplied. Any syscall not
on the list results in SIGKILL being sent to the privsep child. Note
that this requires a kernel with the new SYSTR_POLICY_KILL option.
UsePrivilegeSeparation=sandbox will become the default in the future
so please start testing it now.
feedback dtucker@; ok markus@
Diffstat (limited to 'configure.ac')
-rw-r--r-- | configure.ac | 43 |
1 files changed, 41 insertions, 2 deletions
diff --git a/configure.ac b/configure.ac index 8f36338f..380a8b94 100644 --- a/configure.ac +++ b/configure.ac @@ -1,4 +1,4 @@ -# $Id: configure.ac,v 1.476 2011/06/03 02:11:38 djm Exp $ +# $Id: configure.ac,v 1.477 2011/06/22 22:30:03 djm Exp $ # # Copyright (c) 1999-2004 Damien Miller # @@ -15,7 +15,7 @@ # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. AC_INIT([OpenSSH], [Portable], [openssh-unix-dev@mindrot.org]) -AC_REVISION($Revision: 1.476 $) +AC_REVISION($Revision: 1.477 $) AC_CONFIG_SRCDIR([ssh.c]) AC_LANG([C]) @@ -106,6 +106,16 @@ AC_SUBST([LD]) AC_C_INLINE AC_CHECK_DECL([LLONG_MAX], [have_llong_max=1], , [#include <limits.h>]) +AC_CHECK_DECL([SYSTR_POLICY_KILL], [have_systr_policy_kill=1], , [ + #include <sys/types.h> + #include <sys/param.h> + #include <dev/systrace.h> +]) +AC_CHECK_DECL([RLIMIT_NPROC], + [AC_DEFINE([HAVE_RLIMIT_NPROC], [], [sys/resource.h has RLIMIT_NPROC])], , [ + #include <sys/types.h> + #include <sys/resource.h> +]) use_stack_protector=1 AC_ARG_WITH([stackprotect], @@ -2461,6 +2471,34 @@ AC_DEFINE_UNQUOTED([SSH_PRIVSEP_USER], ["$SSH_PRIVSEP_USER"], [non-privileged user for privilege separation]) AC_SUBST([SSH_PRIVSEP_USER]) +# Decide which sandbox style to use +sandbox_arg="" +AC_ARG_WITH([sandbox], + [ --with-sandbox=style Specify privilege separation sandbox (no, rlimit, systrace)], + [ + if test "x$withval" = "xyes" ; then + sandbox_arg="" + else + sandbox_arg="$withval" + fi + ] +) +if test "x$sandbox_arg" = "xsystrace" || \ + ( test -z "$sandbox_arg" && test "x$have_systr_policy_kill" = "x1" ) ; then + SANDBOX_STYLE="systrace" + AC_DEFINE([SANDBOX_SYSTRACE], [1], [Sandbox using systrace(4)]) +elif test "x$sandbox_arg" = "xrlimit" || \ + ( test -z "$sandbox_arg" && test "x$ac_cv_func_setrlimit" = "xyes" ) ; then + SANDBOX_STYLE="rlimit" + AC_DEFINE([SANDBOX_RLIMIT], [1], [Sandbox using setrlimit(2)]) +elif test -z "$sandbox_arg" || test "x$sandbox_arg" = "xno" || \ + test "x$sandbox_arg" = "xnone" || test "x$sandbox_arg" = "xnull" ; then + SANDBOX_STYLE="none" + AC_DEFINE([SANDBOX_NULL], [1], [no privsep sandboxing]) +else + AC_MSG_ERROR([unsupported -with-sandbox]) +fi + # Cheap hack to ensure NEWS-OS libraries are arranged right. if test ! -z "$SONY" ; then LIBS="$LIBS -liberty"; @@ -4191,6 +4229,7 @@ echo " IP address in \$DISPLAY hack: $DISPLAY_HACK_MSG" echo " Translate v4 in v6 hack: $IPV4_IN6_HACK_MSG" echo " BSD Auth support: $BSD_AUTH_MSG" echo " Random number source: $RAND_MSG" +echo " Privsep sandbox style: $SANDBOX_STYLE" echo "" |