/* -*-c-*-
*
- * $Id: noise.h,v 1.2 1999/12/10 23:29:48 mdw Exp $
+ * $Id: noise.h,v 1.4 2000/06/17 12:57:47 mdw Exp $
*
- * Acquisition of environmental noise (Unix specific)
+ * Acquisition of environmental noise (Unix-specific)
*
* (c) 1998 Straylight/Edgeware
*/
/*----- Revision history --------------------------------------------------*
*
* $Log: noise.h,v $
+ * Revision 1.4 2000/06/17 12:57:47 mdw
+ * New free counter noise generator, for use if /dev/random is
+ * unavailable.
+ *
+ * Revision 1.3 1999/12/22 15:57:55 mdw
+ * Label system-specific parts more clearly.
+ *
* Revision 1.2 1999/12/10 23:29:48 mdw
* Change header file guard names.
*
* 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