* eval_safe.c, safe.c: rename eval_safe.c to safe.c.

* common.mk, eval.c, safe.c, inits.c: separate safe.c from eval.c and
  make Init_safe().



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@19467 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 126 insertions, 0 deletions

diff --git a/safe.c b/safe.c
new file mode 100644
index 0000000000..e351579132
--- /dev/null
+++ b/safe.c
@@ -0,0 +1,126 @@
+/**********************************************************************
+
+  eval.c -
+
+  $Author$
+  created at: Tue Sep 23 09:44:32 JST 2008
+
+  Copyright (C) 2008 Yukihiro Matsumoto
+
+**********************************************************************/
+
+/* safe-level:
+   0 - strings from streams/environment/ARGV are tainted (default)
+   1 - no dangerous operation by tainted value
+   2 - process/file operations prohibited
+   3 - all generated objects are tainted
+   4 - no global (non-tainted) variable modification/no direct output
+*/
+
+#define SAFE_LEVEL_MAX 4
+
+#include "ruby/ruby.h"
+#include "vm_core.h"
+
+/* $SAFE accessor */
+
+int
+rb_safe_level(void)
+{
+    return GET_THREAD()->safe_level;
+}
+
+void
+rb_set_safe_level_force(int safe)
+{
+    GET_THREAD()->safe_level = safe;
+}
+
+void
+rb_set_safe_level(int level)
+{
+    rb_thread_t *th = GET_THREAD();
+
+    if (level > th->safe_level) {
+	if (level > SAFE_LEVEL_MAX) {
+	    level = SAFE_LEVEL_MAX;
+	}
+	th->safe_level = level;
+    }
+}
+
+static VALUE
+safe_getter(void)
+{
+    return INT2NUM(rb_safe_level());
+}
+
+static void
+safe_setter(VALUE val)
+{
+    int level = NUM2INT(val);
+    rb_thread_t *th = GET_THREAD();
+
+    if (level < th->safe_level) {
+	rb_raise(rb_eSecurityError,
+		 "tried to downgrade safe level from %d to %d",
+		 th->safe_level, level);
+    }
+    if (level > SAFE_LEVEL_MAX) {
+	level = SAFE_LEVEL_MAX;
+    }
+    th->safe_level = level;
+}
+
+void
+rb_secure(int level)
+{
+    if (level <= rb_safe_level()) {
+	if (rb_frame_callee()) {
+	    rb_raise(rb_eSecurityError, "Insecure operation `%s' at level %d",
+		     rb_id2name(rb_frame_callee()), rb_safe_level());
+	}
+	else {
+	    rb_raise(rb_eSecurityError, "Insecure operation at level %d",
+		     rb_safe_level());
+	}
+    }
+}
+
+void
+rb_secure_update(VALUE obj)
+{
+    if (!OBJ_TAINTED(obj))
+	rb_secure(4);
+}
+
+void
+rb_check_safe_obj(VALUE x)
+{
+    if (rb_safe_level() > 0 && OBJ_TAINTED(x)) {
+	if (rb_frame_callee()) {
+	    rb_raise(rb_eSecurityError, "Insecure operation - %s",
+		     rb_id2name(rb_frame_callee()));
+	}
+	else {
+	    rb_raise(rb_eSecurityError, "Insecure operation: -r");
+	}
+    }
+    rb_secure(4);
+}
+
+void
+rb_check_safe_str(VALUE x)
+{
+    rb_check_safe_obj(x);
+    if (TYPE(x) != T_STRING) {
+	rb_raise(rb_eTypeError, "wrong argument type %s (expected String)",
+		 rb_obj_classname(x));
+    }
+}
+
+void
+Init_safe(void)
+{
+    rb_define_virtual_variable("$SAFE", safe_getter, safe_setter);
+}