FIPS-140 requires that all random number generators implement continuous self
tests in which each extracted block of data is compared against the last block
for repetition. The ansi_cprng implements such a test, but it would be nice if
the hw rng's did the same thing. Obviously its not something thats always
needed, but it seems like it would be a nice feature to have on occasion. I've
written the below patch which allows individual entropy stores to be flagged as
desiring a continuous test to be run on them as is extracted. By default this
option is off, but is enabled in the event that fips mode is selected during
bootup.
Neil
Signed-off-by: Neil Horman <[email protected]>
diff --git a/crypto/internal.h b/crypto/internal.h
index fc76e1f..150d389 100644
--- a/crypto/internal.h
+++ b/crypto/internal.h
@@ -26,12 +26,6 @@
#include <linux/rwsem.h>
#include <linux/slab.h>
-#ifdef CONFIG_CRYPTO_FIPS
-extern int fips_enabled;
-#else
-#define fips_enabled 0
-#endif
-
/* Crypto notification events. */
enum {
CRYPTO_MSG_ALG_REQUEST,
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 8c74448..fbdfc70 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -250,6 +250,8 @@
#include <asm/irq.h>
#include <asm/io.h>
+#include <crypto/algapi.h>
+
/*
* Configuration information
*/
@@ -400,6 +402,7 @@ module_param(debug, bool, 0644);
**********************************************************************/
struct entropy_store;
+#define ENT_F_CONT_TEST 1
struct entropy_store {
/* read-only data: */
struct poolinfo *poolinfo;
@@ -413,6 +416,8 @@ struct entropy_store {
unsigned add_ptr;
int entropy_count;
int input_rotate;
+ int flags;
+ __u8 *last_data;
};
static __u32 input_pool_data[INPUT_POOL_WORDS];
@@ -424,7 +429,9 @@ static struct entropy_store input_pool = {
.name = "input",
.limit = 1,
.lock = __SPIN_LOCK_UNLOCKED(&input_pool.lock),
- .pool = input_pool_data
+ .pool = input_pool_data,
+ .flags = 0,
+ .last_data = NULL
};
static struct entropy_store blocking_pool = {
@@ -433,7 +440,9 @@ static struct entropy_store blocking_pool = {
.limit = 1,
.pull = &input_pool,
.lock = __SPIN_LOCK_UNLOCKED(&blocking_pool.lock),
- .pool = blocking_pool_data
+ .pool = blocking_pool_data,
+ .flags = 0,
+ .last_data = NULL
};
static struct entropy_store nonblocking_pool = {
@@ -441,7 +450,9 @@ static struct entropy_store nonblocking_pool = {
.name = "nonblocking",
.pull = &input_pool,
.lock = __SPIN_LOCK_UNLOCKED(&nonblocking_pool.lock),
- .pool = nonblocking_pool_data
+ .pool = nonblocking_pool_data,
+ .flags = 0,
+ .last_data = NULL
};
/*
@@ -852,12 +863,21 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf,
{
ssize_t ret = 0, i;
__u8 tmp[EXTRACT_SIZE];
+ unsigned long flags;
xfer_secondary_pool(r, nbytes);
nbytes = account(r, nbytes, min, reserved);
while (nbytes) {
extract_buf(r, tmp);
+
+ if (r->flags & ENT_F_CONT_TEST) {
+ spin_lock_irqsave(&r->lock, flags);
+ if (!memcmp(tmp, r->last_data, EXTRACT_SIZE))
+ panic("Hardware RNG duplicated output!\n");
+ memcpy(r->last_data, tmp, EXTRACT_SIZE);
+ spin_unlock_irqrestore(&r->lock, flags);
+ }
i = min_t(int, nbytes, EXTRACT_SIZE);
memcpy(buf, tmp, i);
nbytes -= i;
@@ -940,6 +960,14 @@ static void init_std_data(struct entropy_store *r)
now = ktime_get_real();
mix_pool_bytes(r, &now, sizeof(now));
mix_pool_bytes(r, utsname(), sizeof(*(utsname())));
+ /* Enable continuous test in fips mode */
+ if (fips_enabled) {
+ r->last_data = kmalloc(EXTRACT_SIZE, GFP_KERNEL);
+ if (r->last_data)
+ r->flags |= ENT_F_CONT_TEST;
+ else
+ panic("Could not alloc data for rng test\n");
+ }
}
static int rand_initialize(void)
diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index 0105454..88e9535 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -20,6 +20,12 @@ struct module;
struct rtattr;
struct seq_file;
+#ifdef CONFIG_CRYPTO_FIPS
+extern int fips_enabled;
+#else
+#define fips_enabled 0
+#endif
+
struct crypto_type {
unsigned int (*ctxsize)(struct crypto_alg *alg, u32 type, u32 mask);
unsigned int (*extsize)(struct crypto_alg *alg,
On Thu, 2009-06-04 at 15:50 -0400, Neil Horman wrote:
> FIPS-140 requires that all random number generators implement continuous self
> tests in which each extracted block of data is compared against the last block
> for repetition. The ansi_cprng implements such a test, but it would be nice if
> the hw rng's did the same thing. Obviously its not something thats always
> needed, but it seems like it would be a nice feature to have on occasion. I've
> written the below patch which allows individual entropy stores to be flagged as
> desiring a continuous test to be run on them as is extracted. By default this
> option is off, but is enabled in the event that fips mode is selected during
> bootup.
>
> Neil
>
> Signed-off-by: Neil Horman <[email protected]>
>
> diff --git a/crypto/internal.h b/crypto/internal.h
> index fc76e1f..150d389 100644
> --- a/crypto/internal.h
> +++ b/crypto/internal.h
> @@ -26,12 +26,6 @@
> #include <linux/rwsem.h>
> #include <linux/slab.h>
>
> -#ifdef CONFIG_CRYPTO_FIPS
> -extern int fips_enabled;
> -#else
> -#define fips_enabled 0
> -#endif
> -
> /* Crypto notification events. */
> enum {
> CRYPTO_MSG_ALG_REQUEST,
> diff --git a/drivers/char/random.c b/drivers/char/random.c
> index 8c74448..fbdfc70 100644
> --- a/drivers/char/random.c
> +++ b/drivers/char/random.c
> @@ -250,6 +250,8 @@
> #include <asm/irq.h>
> #include <asm/io.h>
>
> +#include <crypto/algapi.h>
> +
I think we'd rather not make random.c incestuous with crypto/.
> /*
> * Configuration information
> */
> @@ -400,6 +402,7 @@ module_param(debug, bool, 0644);
> **********************************************************************/
>
> struct entropy_store;
> +#define ENT_F_CONT_TEST 1
> struct entropy_store {
> /* read-only data: */
> struct poolinfo *poolinfo;
> @@ -413,6 +416,8 @@ struct entropy_store {
> unsigned add_ptr;
> int entropy_count;
> int input_rotate;
> + int flags;
> + __u8 *last_data;
> };
>
> static __u32 input_pool_data[INPUT_POOL_WORDS];
> @@ -424,7 +429,9 @@ static struct entropy_store input_pool = {
> .name = "input",
> .limit = 1,
> .lock = __SPIN_LOCK_UNLOCKED(&input_pool.lock),
> - .pool = input_pool_data
> + .pool = input_pool_data,
> + .flags = 0,
> + .last_data = NULL
> };
No need to null-initialize these things.
> static struct entropy_store blocking_pool = {
> @@ -433,7 +440,9 @@ static struct entropy_store blocking_pool = {
> .limit = 1,
> .pull = &input_pool,
> .lock = __SPIN_LOCK_UNLOCKED(&blocking_pool.lock),
> - .pool = blocking_pool_data
> + .pool = blocking_pool_data,
> + .flags = 0,
> + .last_data = NULL
> };
>
> static struct entropy_store nonblocking_pool = {
> @@ -441,7 +450,9 @@ static struct entropy_store nonblocking_pool = {
> .name = "nonblocking",
> .pull = &input_pool,
> .lock = __SPIN_LOCK_UNLOCKED(&nonblocking_pool.lock),
> - .pool = nonblocking_pool_data
> + .pool = nonblocking_pool_data,
> + .flags = 0,
> + .last_data = NULL
> };
>
> /*
> @@ -852,12 +863,21 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf,
> {
> ssize_t ret = 0, i;
> __u8 tmp[EXTRACT_SIZE];
> + unsigned long flags;
>
> xfer_secondary_pool(r, nbytes);
> nbytes = account(r, nbytes, min, reserved);
>
> while (nbytes) {
> extract_buf(r, tmp);
> +
> + if (r->flags & ENT_F_CONT_TEST) {
> + spin_lock_irqsave(&r->lock, flags);
> + if (!memcmp(tmp, r->last_data, EXTRACT_SIZE))
> + panic("Hardware RNG duplicated output!\n");
> + memcpy(r->last_data, tmp, EXTRACT_SIZE);
> + spin_unlock_irqrestore(&r->lock, flags);
> + }
This should go in extract_buf. I think we can avoid adding flags to the
pool struct by simply checking that last_data is not null.
> i = min_t(int, nbytes, EXTRACT_SIZE);
> memcpy(buf, tmp, i);
> nbytes -= i;
> @@ -940,6 +960,14 @@ static void init_std_data(struct entropy_store *r)
> now = ktime_get_real();
> mix_pool_bytes(r, &now, sizeof(now));
> mix_pool_bytes(r, utsname(), sizeof(*(utsname())));
> + /* Enable continuous test in fips mode */
> + if (fips_enabled) {
> + r->last_data = kmalloc(EXTRACT_SIZE, GFP_KERNEL);
> + if (r->last_data)
> + r->flags |= ENT_F_CONT_TEST;
> + else
> + panic("Could not alloc data for rng test\n");
> + }
> }
>
> static int rand_initialize(void)
> diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
> index 0105454..88e9535 100644
> --- a/include/crypto/algapi.h
> +++ b/include/crypto/algapi.h
> @@ -20,6 +20,12 @@ struct module;
> struct rtattr;
> struct seq_file;
>
> +#ifdef CONFIG_CRYPTO_FIPS
> +extern int fips_enabled;
> +#else
> +#define fips_enabled 0
> +#endif
> +
> struct crypto_type {
> unsigned int (*ctxsize)(struct crypto_alg *alg, u32 type, u32 mask);
> unsigned int (*extsize)(struct crypto_alg *alg,
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
--
http://selenic.com : development and support for Mercurial and Linux
On Thu, Jun 04, 2009 at 03:14:10PM -0500, Matt Mackall wrote:
> On Thu, 2009-06-04 at 15:50 -0400, Neil Horman wrote:
> > FIPS-140 requires that all random number generators implement continuous self
> > tests in which each extracted block of data is compared against the last block
> > for repetition. The ansi_cprng implements such a test, but it would be nice if
> > the hw rng's did the same thing. Obviously its not something thats always
> > needed, but it seems like it would be a nice feature to have on occasion. I've
> > written the below patch which allows individual entropy stores to be flagged as
> > desiring a continuous test to be run on them as is extracted. By default this
> > option is off, but is enabled in the event that fips mode is selected during
> > bootup.
> >
> > Neil
> >
> > Signed-off-by: Neil Horman <[email protected]>
> >
> > diff --git a/crypto/internal.h b/crypto/internal.h
> > index fc76e1f..150d389 100644
> > --- a/crypto/internal.h
> > +++ b/crypto/internal.h
> > @@ -26,12 +26,6 @@
> > #include <linux/rwsem.h>
> > #include <linux/slab.h>
> >
> > -#ifdef CONFIG_CRYPTO_FIPS
> > -extern int fips_enabled;
> > -#else
> > -#define fips_enabled 0
> > -#endif
> > -
> > /* Crypto notification events. */
> > enum {
> > CRYPTO_MSG_ALG_REQUEST,
> > diff --git a/drivers/char/random.c b/drivers/char/random.c
> > index 8c74448..fbdfc70 100644
> > --- a/drivers/char/random.c
> > +++ b/drivers/char/random.c
> > @@ -250,6 +250,8 @@
> > #include <asm/irq.h>
> > #include <asm/io.h>
> >
> > +#include <crypto/algapi.h>
> > +
>
> I think we'd rather not make random.c incestuous with crypto/.
>
Not sure what to do about this. The intent is to provide the external reference
to the fips_enabled flag (which is either defined as an extern in or #defined to
0 dependent on CONFIG_CRYPTO_FIPS). I can cut'n'paste the code block from the
include file and put it in here, but that seems like a worse solution to me.
Let me know your thoughts, and I can change this accordingly.
As for the other comments, they all seem good to me, let me know what you want
to do about the above, and I'll respin/repost the patch for you
Thanks!
Neil
On Thu, Jun 04, 2009 at 08:04:56PM -0400, Neil Horman wrote:
>
> Not sure what to do about this. The intent is to provide the external reference
> to the fips_enabled flag (which is either defined as an extern in or #defined to
> 0 dependent on CONFIG_CRYPTO_FIPS). I can cut'n'paste the code block from the
> include file and put it in here, but that seems like a worse solution to me.
> Let me know your thoughts, and I can change this accordingly.
You can put the fips flag into its own header file, e.g., linux/fips.h.
Cheers,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
On Fri, Jun 05, 2009 at 10:30:06AM +1000, Herbert Xu wrote:
> On Thu, Jun 04, 2009 at 08:04:56PM -0400, Neil Horman wrote:
> >
> > Not sure what to do about this. The intent is to provide the external reference
> > to the fips_enabled flag (which is either defined as an extern in or #defined to
> > 0 dependent on CONFIG_CRYPTO_FIPS). I can cut'n'paste the code block from the
> > include file and put it in here, but that seems like a worse solution to me.
> > Let me know your thoughts, and I can change this accordingly.
>
> You can put the fips flag into its own header file, e.g., linux/fips.h.
>
Ok, that seems like a reasonable idea. new patch below
Change Notes:
1) Moved fips_enabled flag into its own header, included in all the appropriate
places
2) removed flags field from entropy store, keying continuous test on the
non-null status of the last_data pointer
FIPS-140 requires that all random number generators implement continuous self
tests in which each extracted block of data is compared against the last block
for repetition. The ansi_cprng implements such a test, but it would be nice if
the hw rng's did the same thing. Obviously its not something thats always
needed, but it seems like it would be a nice feature to have on occasion. I've
written the below patch which allows individual entropy stores to be flagged as
desiring a continuous test to be run on them as is extracted. By default this
option is off, but is enabled in the event that fips mode is selected during
bootup.
Neil
Signed-off-by: Neil Horman <[email protected]>
crypto/internal.h | 7 +------
drivers/char/random.c | 14 ++++++++++++++
include/linux/fips.h | 10 ++++++++++
3 files changed, 25 insertions(+), 6 deletions(-)
diff --git a/crypto/internal.h b/crypto/internal.h
index fc76e1f..769b713 100644
--- a/crypto/internal.h
+++ b/crypto/internal.h
@@ -25,12 +25,7 @@
#include <linux/notifier.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
-
-#ifdef CONFIG_CRYPTO_FIPS
-extern int fips_enabled;
-#else
-#define fips_enabled 0
-#endif
+#include <linux/fips.h>
/* Crypto notification events. */
enum {
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 8c74448..d8a9255 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -240,6 +240,7 @@
#include <linux/spinlock.h>
#include <linux/percpu.h>
#include <linux/cryptohash.h>
+#include <linux/fips.h>
#ifdef CONFIG_GENERIC_HARDIRQS
# include <linux/irq.h>
@@ -413,6 +414,7 @@ struct entropy_store {
unsigned add_ptr;
int entropy_count;
int input_rotate;
+ __u8 *last_data;
};
static __u32 input_pool_data[INPUT_POOL_WORDS];
@@ -852,12 +854,21 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf,
{
ssize_t ret = 0, i;
__u8 tmp[EXTRACT_SIZE];
+ unsigned long flags;
xfer_secondary_pool(r, nbytes);
nbytes = account(r, nbytes, min, reserved);
while (nbytes) {
extract_buf(r, tmp);
+
+ if (r->last_data) {
+ spin_lock_irqsave(&r->lock, flags);
+ if (!memcmp(tmp, r->last_data, EXTRACT_SIZE))
+ panic("Hardware RNG duplicated output!\n");
+ memcpy(r->last_data, tmp, EXTRACT_SIZE);
+ spin_unlock_irqrestore(&r->lock, flags);
+ }
i = min_t(int, nbytes, EXTRACT_SIZE);
memcpy(buf, tmp, i);
nbytes -= i;
@@ -940,6 +951,9 @@ static void init_std_data(struct entropy_store *r)
now = ktime_get_real();
mix_pool_bytes(r, &now, sizeof(now));
mix_pool_bytes(r, utsname(), sizeof(*(utsname())));
+ /* Enable continuous test in fips mode */
+ if (fips_enabled)
+ r->last_data = kmalloc(EXTRACT_SIZE, GFP_KERNEL);
}
static int rand_initialize(void)
diff --git a/include/linux/fips.h b/include/linux/fips.h
new file mode 100644
index 0000000..f8fb07b
--- /dev/null
+++ b/include/linux/fips.h
@@ -0,0 +1,10 @@
+#ifndef _FIPS_H
+#define _FIPS_H
+
+#ifdef CONFIG_CRYPTO_FIPS
+extern int fips_enabled;
+#else
+#define fips_enabled 0
+#endif
+
+#endif
> Cheers,
> --
> Visit Openswan at http://www.openswan.org/
> Email: Herbert Xu ~{PmV>HI~} <[email protected]>
> Home Page: http://gondor.apana.org.au/~herbert/
> PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
>
On Thu, Jun 04, 2009 at 09:48:16PM -0400, Neil Horman wrote:
> On Fri, Jun 05, 2009 at 10:30:06AM +1000, Herbert Xu wrote:
> > On Thu, Jun 04, 2009 at 08:04:56PM -0400, Neil Horman wrote:
> > >
> > > Not sure what to do about this. The intent is to provide the external reference
> > > to the fips_enabled flag (which is either defined as an extern in or #defined to
> > > 0 dependent on CONFIG_CRYPTO_FIPS). I can cut'n'paste the code block from the
> > > include file and put it in here, but that seems like a worse solution to me.
> > > Let me know your thoughts, and I can change this accordingly.
> >
> > You can put the fips flag into its own header file, e.g., linux/fips.h.
> >
>
> Ok, that seems like a reasonable idea. new patch below
> Change Notes:
>
> 1) Moved fips_enabled flag into its own header, included in all the appropriate
> places
>
> 2) removed flags field from entropy store, keying continuous test on the
> non-null status of the last_data pointer
>
>
> FIPS-140 requires that all random number generators implement continuous self
> tests in which each extracted block of data is compared against the last block
> for repetition. The ansi_cprng implements such a test, but it would be nice if
> the hw rng's did the same thing. Obviously its not something thats always
> needed, but it seems like it would be a nice feature to have on occasion. I've
> written the below patch which allows individual entropy stores to be flagged as
> desiring a continuous test to be run on them as is extracted. By default this
> option is off, but is enabled in the event that fips mode is selected during
> bootup.
>
> Neil
>
> Signed-off-by: Neil Horman <[email protected]>
>
Ping, I don't see that this got picked up in the crypto tree. Are there
subsequent objections?
Neil
On Fri, Jun 12, 2009 at 10:23:08AM -0400, Neil Horman wrote:
>
> > Ok, that seems like a reasonable idea. new patch below
> > Change Notes:
> >
> > 1) Moved fips_enabled flag into its own header, included in all the appropriate
> > places
> >
> > 2) removed flags field from entropy store, keying continuous test on the
> > non-null status of the last_data pointer
> >
> >
> > FIPS-140 requires that all random number generators implement continuous self
> > tests in which each extracted block of data is compared against the last block
> > for repetition. The ansi_cprng implements such a test, but it would be nice if
> > the hw rng's did the same thing. Obviously its not something thats always
> > needed, but it seems like it would be a nice feature to have on occasion. I've
> > written the below patch which allows individual entropy stores to be flagged as
> > desiring a continuous test to be run on them as is extracted. By default this
> > option is off, but is enabled in the event that fips mode is selected during
> > bootup.
> >
> > Neil
> >
> > Signed-off-by: Neil Horman <[email protected]>
> >
> Ping, I don't see that this got picked up in the crypto tree. Are there
> subsequent objections?
Matt, are you OK with me picking this up or do you want to pick it
up?
Cheers,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
On Sat, 2009-06-13 at 00:26 +1000, Herbert Xu wrote:
> On Fri, Jun 12, 2009 at 10:23:08AM -0400, Neil Horman wrote:
> >
> > > Ok, that seems like a reasonable idea. new patch below
> > > Change Notes:
> > >
> > > 1) Moved fips_enabled flag into its own header, included in all the appropriate
> > > places
> > >
> > > 2) removed flags field from entropy store, keying continuous test on the
> > > non-null status of the last_data pointer
> > >
> > >
> > > FIPS-140 requires that all random number generators implement continuous self
> > > tests in which each extracted block of data is compared against the last block
> > > for repetition. The ansi_cprng implements such a test, but it would be nice if
> > > the hw rng's did the same thing. Obviously its not something thats always
> > > needed, but it seems like it would be a nice feature to have on occasion. I've
> > > written the below patch which allows individual entropy stores to be flagged as
> > > desiring a continuous test to be run on them as is extracted. By default this
> > > option is off, but is enabled in the event that fips mode is selected during
> > > bootup.
> > >
> > > Neil
> > >
> > > Signed-off-by: Neil Horman <[email protected]>
> > >
> > Ping, I don't see that this got picked up in the crypto tree. Are there
> > subsequent objections?
>
> Matt, are you OK with me picking this up or do you want to pick it
> up?
Acked-by: Matt Mackall <[email protected]>
You can pick it up. Speaking of, do you care if I route other RNG bits
through your crypto tree? I usually just bounce patches to Andrew.
--
http://selenic.com : development and support for Mercurial and Linux
On Fri, Jun 12, 2009 at 11:31:11AM -0500, Matt Mackall wrote:
>
> Acked-by: Matt Mackall <[email protected]>
Thanks, I'll add it to cryptodev.
> You can pick it up. Speaking of, do you care if I route other RNG bits
> through your crypto tree? I usually just bounce patches to Andrew.
Sure no problems. Just cc me or [email protected] when
you ack it and I can pick them up.
Cheers,
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
On Fri, Jun 12, 2009 at 11:31:11AM -0500, Matt Mackall wrote:
>
> Acked-by: Matt Mackall <[email protected]>
Patch applied to cryptodev. Thanks everyone.
--
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt