From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932386Ab2HOUBZ (ORCPT ); Wed, 15 Aug 2012 16:01:25 -0400 Received: from mail1.windriver.com ([147.11.146.13]:63145 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932139Ab2HOTwn (ORCPT ); Wed, 15 Aug 2012 15:52:43 -0400 From: Paul Gortmaker To: , CC: "H. Peter Anvin" , "H. Peter Anvin" , Fenghua Yu , Matt Mackall , Herbert Xu , "Theodore Ts'o" , Paul Gortmaker Subject: [v2.6.34-stable 144/165] random: Add support for architectural random hooks Date: Wed, 15 Aug 2012 15:48:08 -0400 Message-ID: <1345060109-9187-145-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.12.rc2 In-Reply-To: <1345060109-9187-1-git-send-email-paul.gortmaker@windriver.com> References: <1345060109-9187-1-git-send-email-paul.gortmaker@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "H. Peter Anvin" ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. ------------------- commit 63d77173266c1791f1553e9e8ccea65dc87c4485 upstream. Add support for architecture-specific hooks into the kernel-directed random number generator interfaces. This patchset does not use the architecture random number generator interfaces for the userspace-directed interfaces (/dev/random and /dev/urandom), thus eliminating the need to distinguish between them based on a pool pointer. Changes in version 3: - Moved the hooks from extract_entropy() to get_random_bytes(). - Changes the hooks to inlines. Signed-off-by: H. Peter Anvin Cc: Fenghua Yu Cc: Matt Mackall Cc: Herbert Xu Cc: "Theodore Ts'o" [PG: .34 already had "unsigned int ret" in get_random_int, so the diffstat here is slightly smaller than that of 63d7717. ] Signed-off-by: Paul Gortmaker --- drivers/char/random.c | 23 +++++++++++++++++++++-- include/linux/random.h | 13 +++++++++++++ 2 files changed, 34 insertions(+), 2 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 1e07bbe..6da0696 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -925,7 +925,21 @@ static ssize_t extract_entropy_user(struct entropy_store *r, void __user *buf, */ void get_random_bytes(void *buf, int nbytes) { - extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0); + char *p = buf; + + while (nbytes) { + unsigned long v; + int chunk = min(nbytes, (int)sizeof(unsigned long)); + + if (!arch_get_random_long(&v)) + break; + + memcpy(buf, &v, chunk); + p += chunk; + nbytes -= chunk; + } + + extract_entropy(&nonblocking_pool, p, nbytes, 0, 0); } EXPORT_SYMBOL(get_random_bytes); @@ -1309,9 +1323,14 @@ late_initcall(random_int_secret_init); DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash); unsigned int get_random_int(void) { - __u32 *hash = get_cpu_var(get_random_int_hash); + __u32 *hash; unsigned int ret; + if (arch_get_random_int(&ret)) + return ret; + + hash = get_cpu_var(get_random_int_hash); + hash[0] += current->pid + jiffies + get_cycles(); md5_transform(hash, random_int_secret); ret = hash[0]; diff --git a/include/linux/random.h b/include/linux/random.h index 2948046..0bf2936 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -63,6 +63,19 @@ unsigned long randomize_range(unsigned long start, unsigned long end, unsigned l u32 random32(void); void srandom32(u32 seed); +#ifdef CONFIG_ARCH_RANDOM +# include +#else +static inline int arch_get_random_long(unsigned long *v) +{ + return 0; +} +static inline int arch_get_random_int(unsigned int *v) +{ + return 0; +} +#endif + #endif /* __KERNEL___ */ #endif /* _LINUX_RANDOM_H */ -- 1.7.12.rc2