/* -*-c-*-
*
- * $Id: noise.h,v 1.1 1999/09/03 08:41:12 mdw Exp $
+ * $Id: noise.h,v 1.6 2004/04/08 01:36:15 mdw Exp $
*
- * Acquisition of environmental noise (Unix specific)
+ * Acquisition of environmental noise (Unix-specific)
*
* (c) 1998 Straylight/Edgeware
*/
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: noise.h,v $
- * Revision 1.1 1999/09/03 08:41:12 mdw
- * Initial import.
- *
- */
-
-#ifndef NOISE_H
-#define NOISE_H
+#ifndef CATACOMB_NOISE_H
+#define CATACOMB_NOISE_H
#ifdef __cplusplus
extern "C" {
#include <sys/types.h>
-#ifndef RAND_H
+#ifndef CATACOMB_RAND_H
# include "rand.h"
#endif
/*----- Noise source definition -------------------------------------------*/
-extern rand_source noise_source;
+extern const rand_source noise_source;
/*----- Magic numbers -----------------------------------------------------*/
* Use: Sets the user and group ids to be used by @noise_filter@
* when running child processes. This is useful to avoid
* giving shell commands (even carefully written ones) undue
- * privileges.
+ * privileges. This interface is Unix-specific.
*/
extern void noise_setid(uid_t /*uid*/, gid_t /*gid*/);
* fails to complete within a short time period, it is killed.
* Paranoid use of close-on-exec flags for file descriptors is
* recommended.
+ *
+ * This interface is Unix-specific.
*/
extern int noise_filter(rand_pool */*r*/, int /*good*/, const char */*c*/);
+/* --- @noise_freewheel@ --- *
+ *
+ * Arguments: @rand_pool *r@ = pointer to a randomness pool
+ *
+ * Returns: Nonzero if some randomness was contributed.
+ *
+ * Use: Runs a free counter for a short while as a desparate attempt
+ * to get randomness from somewhere. This is actually quite
+ * effective.
+ */
+
+int noise_freewheel(rand_pool */*r*/);
+
+/* --- @noise_enquire@ --- *
+ *
+ * Arguments: @rand_pool *r@ = pointer to a randomness pool
+ *
+ * Returns: Nonzero if some randomness was contributed.
+ *
+ * Use: Runs some shell commands to enquire about the prevailing
+ * environment. This can gather quite a lot of low-quality
+ * entropy.
+ */
+
+extern int noise_enquire(rand_pool */*r*/);
+
/* --- @noise_acquire@ --- *
*
* Arguments: @rand_pool *r@ = pointer to a randomness pool