Cache timezone data in capsicum sandbox.

From emaste at freebsd.org, originally part of FreeBSD commit r339216
/ fc3c19a9 with autoconf bits added by me.

configure.ac

@@ -504,12 +504,20 @@ AC_CHECK_HEADERS([sys/audit.h], [], [], [
 ])
 
 # sys/capsicum.h requires sys/types.h
-AC_CHECK_HEADERS([sys/capsicum.h], [], [], [
+AC_CHECK_HEADERS([sys/capsicum.h capsicum_helpers.h], [], [], [
 #ifdef HAVE_SYS_TYPES_H
 # include <sys/types.h>
 #endif
 ])
 
+AC_MSG_CHECKING([for caph_cache_tzdata])
+AC_LINK_IFELSE(
+    [AC_LANG_PROGRAM([[ #include <capsicum_helpers.h> ]],
+	[[caph_cache_tzdata();]])],
+    [ AC_MSG_RESULT([yes]) ],
+    [ AC_MSG_RESULT([no]) ]
+)
+
 # net/route.h requires sys/socket.h and sys/types.h.
 # sys/sysctl.h also requires sys/param.h
 AC_CHECK_HEADERS([net/route.h sys/sysctl.h], [], [], [

sandbox-capsicum.c

@@ -29,6 +29,9 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#ifdef HAVE_CAPSICUM_HELPERS_H
+#include <capsicum_helpers.h>
+#endif
 
 #include "log.h"
 #include "monitor.h"
@@ -69,6 +72,10 @@ ssh_sandbox_child(struct ssh_sandbox *box)
 	struct rlimit rl_zero;
 	cap_rights_t rights;
 
+#ifdef HAVE_CAPH_CACHE_TZDATA
+	caph_cache_tzdata();
+#endif
+
 	rl_zero.rlim_cur = rl_zero.rlim_max = 0;
 
 	if (setrlimit(RLIMIT_FSIZE, &rl_zero) == -1)