As the blocking model has seems to be troublesome for many, disable

it for now with an option.

This option is already deprecated, and will be removed when the
entropy-harvesting code is fast enough to warrant it.

11 files changed, 30 insertions, 1 deletions

diff --git a/sys/alpha/conf/GENERIC b/sys/alpha/conf/GENERIC
index aac72b2..bd740b0 100644
--- a/sys/alpha/conf/GENERIC
+++ b/sys/alpha/conf/GENERIC
@@ -153,6 +153,7 @@ device		xl		# 3Com 3c90x (``Boomerang'', ``Cyclone'')
 
 # Pseudo devices - the number indicates how many units to allocated.
 device		random		# Entropy device
+options 	NOBLOCKRANDOM	# avoid any blocking on device random
 device		loop		# Network loopback
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
diff --git a/sys/alpha/conf/NOTES b/sys/alpha/conf/NOTES
index aac72b2..bd740b0 100644
--- a/sys/alpha/conf/NOTES
+++ b/sys/alpha/conf/NOTES
@@ -153,6 +153,7 @@ device		xl		# 3Com 3c90x (``Boomerang'', ``Cyclone'')
 
 # Pseudo devices - the number indicates how many units to allocated.
 device		random		# Entropy device
+options 	NOBLOCKRANDOM	# avoid any blocking on device random
 device		loop		# Network loopback
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
diff --git a/sys/amd64/conf/GENERIC b/sys/amd64/conf/GENERIC
index 694a55c..34887d3 100644
--- a/sys/amd64/conf/GENERIC
+++ b/sys/amd64/conf/GENERIC
@@ -207,6 +207,7 @@ device		lnc
 
 # Pseudo devices - the number indicates how many units to allocated.
 device		random		# Entropy device
+options 	NOBLOCKRANDOM	# avoid any blocking on device random
 device		loop		# Network loopback
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index 1103ccf..3a992c2 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -764,6 +764,9 @@ options 	ENABLE_VFS_IOOPT
 # Cryptographically secure random number generator; /dev/[u]random
 device		random
 
+# Avoid blocking the random device
+options		NOBLOCKRANDOM
+
 
 #####################################################################
 # POSIX P1003.1B
diff --git a/sys/conf/options b/sys/conf/options
index 6f86d74..f888a9f 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -477,3 +477,6 @@ ACPI_NO_ENABLE_ON_BOOT	opt_acpi.h
 # options for DEVFS, see sys/fs/devfs/devfs.h
 NDEVFSINO		opt_devfs.h
 NDEVFSOVERFLOW		opt_devfs.h
+
+# options for device random
+NOBLOCKRANDOM
diff --git a/sys/dev/random/randomdev.c b/sys/dev/random/randomdev.c
index c8d2eba..2f3e4a3 100644
--- a/sys/dev/random/randomdev.c
+++ b/sys/dev/random/randomdev.c
@@ -49,6 +49,8 @@
 #include <dev/random/hash.h>
 #include <dev/random/yarrow.h>
 
+#include "opt_noblockrandom.h"
+
 static d_open_t random_open;
 static d_read_t random_read;
 static d_write_t random_write;
@@ -109,6 +111,8 @@ random_read(dev_t dev, struct uio *uio, int flag)
 	int error = 0;
 	void *random_buf;
 
+/* XXX Temporary ifndef to allow users to have a nonblocking device */
+#ifndef NOBLOCKRANDOM
 	while (!random_state.seeded) {
 		if (flag & IO_NDELAY)
 			error =  EWOULDBLOCK;
@@ -117,6 +121,7 @@ random_read(dev_t dev, struct uio *uio, int flag)
 		if (error != 0)
 			return error;
 	}
+#endif
 	c = min(uio->uio_resid, PAGE_SIZE);
 	random_buf = (void *)malloc(c, M_TEMP, M_WAITOK);
 	while (uio->uio_resid > 0 && error == 0) {
diff --git a/sys/i386/conf/GENERIC b/sys/i386/conf/GENERIC
index 694a55c..34887d3 100644
--- a/sys/i386/conf/GENERIC
+++ b/sys/i386/conf/GENERIC
@@ -207,6 +207,7 @@ device		lnc
 
 # Pseudo devices - the number indicates how many units to allocated.
 device		random		# Entropy device
+options 	NOBLOCKRANDOM	# avoid any blocking on device random
 device		loop		# Network loopback
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index 1103ccf..3a992c2 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -764,6 +764,9 @@ options 	ENABLE_VFS_IOOPT
 # Cryptographically secure random number generator; /dev/[u]random
 device		random
 
+# Avoid blocking the random device
+options		NOBLOCKRANDOM
+
 
 #####################################################################
 # POSIX P1003.1B
diff --git a/sys/ia64/conf/GENERIC b/sys/ia64/conf/GENERIC
index 7ba5107..244659e 100644
--- a/sys/ia64/conf/GENERIC
+++ b/sys/ia64/conf/GENERIC
@@ -135,6 +135,7 @@ device		xl		# 3Com 3c90x (``Boomerang'', ``Cyclone'')
 
 # Pseudo devices - the number indicates how many units to allocated.
 device		random		# Entropy device
+options 	NOBLOCKRANDOM	# avoid any blocking on device random
 device		loop		# Network loopback
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
diff --git a/sys/modules/random/Makefile b/sys/modules/random/Makefile
index 5b2a261..d736feb 100644
--- a/sys/modules/random/Makefile
+++ b/sys/modules/random/Makefile
@@ -5,8 +5,17 @@
 KMOD	= random
 SRCS	= bus_if.h device_if.h randomdev.c yarrow.c hash.c
 SRCS	+= bf_cbc.c bf_skey.c bf_enc.c
-SRCS	+= vnode_if.h
+SRCS	+= vnode_if.h opt_noblockrandom.h
 CFLAGS	+= -I${.CURDIR}/../..
 NOMAN	= yes
 
+NOBLOCKRANDOM=	yes
+.if defined(NOBLOCKRANDOM)
+RANDOM_OPTS=     "\#define NOBLOCKRANDOM"
+.endif
+
+opt_noblockrandom.h:
+	touch opt_noblockrandom.h
+	echo $(RANDOM_OPTS) >> opt_noblockrandom.h
+
 .include <bsd.kmod.mk>
diff --git a/sys/pc98/conf/GENERIC b/sys/pc98/conf/GENERIC
index ab7e580..235a56c 100644
--- a/sys/pc98/conf/GENERIC
+++ b/sys/pc98/conf/GENERIC
@@ -222,6 +222,7 @@ device		xe
 
 # Pseudo devices - the number indicates how many units to allocated.
 device		random		# Entropy device
+options 	NOBLOCKRANDOM	# avoid any blocking on device random
 device		loop		# Network loopback
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP