Decouple yarrow from random(4) device.

* Make Yarrow an optional kernel component -- enabled by "YARROW_RNG" option.
  The files sha2.c, hash.c, randomdev_soft.c and yarrow.c comprise yarrow.

* random(4) device doesn't really depend on rijndael-*.  Yarrow, however, does.

* Add random_adaptors.[ch] which is basically a store of random_adaptor's.
  random_adaptor is basically an adapter that plugs in to random(4).
  random_adaptor can only be plugged in to random(4) very early in bootup.
  Unplugging random_adaptor from random(4) is not supported, and is probably a
  bad idea anyway, due to potential loss of entropy pools.
  We currently have 3 random_adaptors:
  + yarrow
  + rdrand (ivy.c)
  + nehemeiah

* Remove platform dependent logic from probe.c, and move it into
  corresponding registration routines of each random_adaptor provider.
  probe.c doesn't do anything other than picking a specific random_adaptor
  from a list of registered ones.

* If the kernel doesn't have any random_adaptor adapters present then the
  creation of /dev/random is postponed until next random_adaptor is kldload'ed.

* Fix randomdev_soft.c to refer to its own random_adaptor, instead of a
  system wide one.

Submitted by: arthurmesh@gmail.com, obrien
Obtained from: Juniper Networks
Reviewed by: obrien

1 files changed, 2 insertions, 2 deletions

diff --git a/sys/dev/random/randomdev_soft.h b/sys/dev/random/randomdev_soft.h
index 489d45a..2007694 100644
--- a/sys/dev/random/randomdev_soft.h
+++ b/sys/dev/random/randomdev_soft.h
@@ -72,10 +72,10 @@ void random_process_event(struct harvest *event);
 void random_yarrow_reseed(void);
 void random_yarrow_unblock(void);
 
-void random_yarrow_init_alg(struct sysctl_ctx_list *, struct sysctl_oid *);
+void random_yarrow_init_alg(struct sysctl_ctx_list *);
 void random_yarrow_deinit_alg(void);
 
-extern struct random_systat random_yarrow;
+extern struct random_adaptor random_yarrow;
 extern struct mtx random_reseed_mtx;
 
 /* If this was c++, this would be a template */