Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261720AbVCJE3y (ORCPT ); Wed, 9 Mar 2005 23:29:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262562AbVCIXyP (ORCPT ); Wed, 9 Mar 2005 18:54:15 -0500 Received: from lakshmi.addtoit.com ([198.99.130.6]:15630 "EHLO lakshmi.solana.com") by vger.kernel.org with ESMTP id S261565AbVCIXpl (ORCPT ); Wed, 9 Mar 2005 18:45:41 -0500 Message-Id: <200503100215.j2A2FuDN015227@ccure.user-mode-linux.org> X-Mailer: exmh version 2.4 06/23/2000 with nmh-1.1-RC1 To: torvalds@osdl.org cc: akpm@osdl.org, linux-kernel@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net Subject: [PATCH 3/9] UML - "Hardware" random number generator Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 09 Mar 2005 21:15:56 -0500 From: Jeff Dike Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5927 Lines: 196 This implements a hardware random number generator for UML which attaches itself to the host's /dev/random. Signed-off-by: Jeff Dike Index: linux-2.6.11/arch/um/Kconfig_char =================================================================== --- linux-2.6.11.orig/arch/um/Kconfig_char 2005-03-08 20:13:55.000000000 -0500 +++ linux-2.6.11/arch/um/Kconfig_char 2005-03-08 20:22:24.000000000 -0500 @@ -190,5 +190,19 @@ tristate default UML_SOUND +config UML_RANDOM + tristate "Hardware random number generator" + help + This option enables UML's "hardware" random number generator. It + attaches itself to the host's /dev/random, supplying as much entropy + as the host has, rather than the small amount the UML gets from its + own drivers. It registers itself as a standard hardware random number + generator, major 10, minor 183, and the canonical device name is + /dev/hwrng. + The way to make use of this is to install the rng-tools package + (check your distro, or download from + http://sourceforge.net/projects/gkernel/). rngd periodically reads + /dev/hwrng and injects the entropy into /dev/random. + endmenu Index: linux-2.6.11/arch/um/defconfig =================================================================== --- linux-2.6.11.orig/arch/um/defconfig 2005-03-08 20:13:55.000000000 -0500 +++ linux-2.6.11/arch/um/defconfig 2005-03-08 20:22:24.000000000 -0500 @@ -111,6 +111,7 @@ CONFIG_UML_SOUND=m CONFIG_SOUND=m CONFIG_HOSTAUDIO=m +CONFIG_UML_RANDOM=y # # Block devices Index: linux-2.6.11/arch/um/drivers/Makefile =================================================================== --- linux-2.6.11.orig/arch/um/drivers/Makefile 2005-03-08 20:17:34.000000000 -0500 +++ linux-2.6.11/arch/um/drivers/Makefile 2005-03-08 20:22:24.000000000 -0500 @@ -3,7 +3,7 @@ # Licensed under the GPL # -CHAN_OBJS := chan_kern.o chan_user.o line.o +CHAN_OBJS := chan_kern.o chan_user.o line.o # pcap is broken in 2.5 because kbuild doesn't allow pcap.a to be linked # in to pcap.o @@ -41,7 +41,7 @@ obj-$(CONFIG_XTERM_CHAN) += xterm.o xterm_kern.o obj-$(CONFIG_UML_WATCHDOG) += harddog.o obj-$(CONFIG_BLK_DEV_COW_COMMON) += cow_user.o - +obj-$(CONFIG_UML_RANDOM) += random.o USER_SINGLE_OBJS = $(foreach f,$(patsubst %.o,%,$(obj-y) $(obj-m)),$($(f)-objs)) Index: linux-2.6.11/arch/um/drivers/random.c =================================================================== --- linux-2.6.11.orig/arch/um/drivers/random.c 2003-09-15 09:40:47.000000000 -0400 +++ linux-2.6.11/arch/um/drivers/random.c 2005-03-08 20:22:24.000000000 -0500 @@ -0,0 +1,122 @@ +/* Much of this ripped from hw_random.c */ + +#include +#include +#include +#include +#include +#include "os.h" + +/* + * core module and version information + */ +#define RNG_VERSION "1.0.0" +#define RNG_MODULE_NAME "random" +#define RNG_DRIVER_NAME RNG_MODULE_NAME " virtual driver " RNG_VERSION +#define PFX RNG_MODULE_NAME ": " + +#define RNG_MISCDEV_MINOR 183 /* official */ + +static int random_fd = -1; + +static int rng_dev_open (struct inode *inode, struct file *filp) +{ + /* enforce read-only access to this chrdev */ + if ((filp->f_mode & FMODE_READ) == 0) + return -EINVAL; + if (filp->f_mode & FMODE_WRITE) + return -EINVAL; + + return 0; +} + +static ssize_t rng_dev_read (struct file *filp, char __user *buf, size_t size, + loff_t * offp) +{ + u32 data; + int n, ret = 0, have_data; + + while(size){ + n = os_read_file(random_fd, &data, sizeof(data)); + if(n > 0){ + have_data = n; + while (have_data && size) { + if (put_user((u8)data, buf++)) { + ret = ret ? : -EFAULT; + break; + } + size--; + ret++; + have_data--; + data>>=8; + } + } + else if(n == -EAGAIN){ + if (filp->f_flags & O_NONBLOCK) + return ret ? : -EAGAIN; + + if(need_resched()){ + current->state = TASK_INTERRUPTIBLE; + schedule_timeout(1); + } + } + else return n; + if (signal_pending (current)) + return ret ? : -ERESTARTSYS; + } + return ret; +} + +static struct file_operations rng_chrdev_ops = { + .owner = THIS_MODULE, + .open = rng_dev_open, + .read = rng_dev_read, +}; + +static struct miscdevice rng_miscdev = { + RNG_MISCDEV_MINOR, + RNG_MODULE_NAME, + &rng_chrdev_ops, +}; + +/* + * rng_init - initialize RNG module + */ +static int __init rng_init (void) +{ + int err; + + err = os_open_file("/dev/random", of_read(OPENFLAGS()), 0); + if(err < 0) + goto out; + + random_fd = err; + + err = os_set_fd_block(random_fd, 0); + if(err) + goto err_out_cleanup_hw; + + err = misc_register (&rng_miscdev); + if (err) { + printk (KERN_ERR PFX "misc device register failed\n"); + goto err_out_cleanup_hw; + } + + out: + return err; + + err_out_cleanup_hw: + random_fd = -1; + goto out; +} + +/* + * rng_cleanup - shutdown RNG module + */ +static void __exit rng_cleanup (void) +{ + misc_deregister (&rng_miscdev); +} + +module_init (rng_init); +module_exit (rng_cleanup); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/