2006-12-15 18:54:24

by Anderson Briglia

[permalink] [raw]
Subject: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Implement MMC password force erase, remove password, change password,
unlock card and assign password operations. It uses the sysfs mechanism
to send commands to the MMC subsystem.

Signed-off-by: Carlos Eduardo Aguiar <carlos.aguiar <at> indt.org.br>
Signed-off-by: Anderson Lizardo <anderson.lizardo <at> indt.org.br>
Signed-off-by: Anderson Briglia <anderson.briglia <at> indt.org.br>

Index: linux-linus-2.6/drivers/mmc/mmc_sysfs.c
===================================================================
--- linux-linus-2.6.orig/drivers/mmc/mmc_sysfs.c 2006-12-15 14:35:14.000000000 -0400
+++ linux-linus-2.6/drivers/mmc/mmc_sysfs.c 2006-12-15 14:35:27.000000000 -0400
@@ -17,6 +17,7 @@
#include <linux/idr.h>
#include <linux/workqueue.h>
#include <linux/key.h>
+#include <linux/err.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
@@ -65,6 +66,100 @@ static struct device_attribute mmc_dev_a

static struct device_attribute mmc_dev_attr_scr = MMC_ATTR_RO(scr);

+#ifdef CONFIG_MMC_PASSWORDS
+
+static ssize_t
+mmc_lockable_show(struct device *dev, struct device_attribute *att, char *buf)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+
+ if (!mmc_card_lockable(card))
+ return sprintf(buf, "unsupported\n");
+ else
+ return sprintf(buf, "%slocked\n", mmc_card_locked(card) ?
+ "" : "un");
+}
+
+/*
+ * implement MMC password functions: force erase, remove password, change
+ * password, unlock card and assign password.
+ */
+static ssize_t
+mmc_lockable_store(struct device *dev, struct device_attribute *att,
+ const char *data, size_t len)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+ int err = 0;
+
+ err = mmc_card_claim_host(card);
+ if (err != MMC_ERR_NONE)
+ return -EINVAL;
+
+ if (!mmc_card_lockable(card))
+ return -EINVAL;
+
+ if (mmc_card_locked(card) && !strncmp(data, "erase", 5)) {
+ /* forced erase only works while card is locked */
+ mmc_lock_unlock(card, NULL, MMC_LOCK_MODE_ERASE);
+ goto out;
+ } else if (!mmc_card_locked(card) && !strncmp(data, "remove", 6)) {
+ /* remove password only works while card is unlocked */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "remove");
+
+ if (!IS_ERR(mmc_key)) {
+ int err = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_CLR_PWD);
+ if (!err)
+ goto out;
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (!mmc_card_locked(card) && ((!strncmp(data, "assign", 6)) ||
+ (!strncmp(data, "change", 6)))) {
+
+ /* assign or change */
+ struct key *mmc_key;
+
+ if(!strncmp(data, "assign", 6))
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "assign");
+ else
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "change");
+
+ if (!IS_ERR(mmc_key)) {
+ int err = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_SET_PWD);
+ if (!err)
+ goto out;
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (mmc_card_locked(card) && !strncmp(data, "unlock", 6)) {
+ /* unlock */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "unlock");
+ if (!IS_ERR(mmc_key)) {
+ int err = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_UNLOCK);
+ if (err) {
+ dev_dbg(&card->dev, "Wrong password\n");
+ }
+ else {
+ mmc_card_release_host(card);
+ device_release_driver(dev);
+ device_attach(dev);
+ return len;
+ }
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ }
+
+ mmc_card_release_host(card);
+ return -EINVAL;
+out:
+ mmc_card_release_host(card);
+ return len;
+}
+
+static struct device_attribute mmc_dev_attr_lockable =
+ __ATTR(lockable, S_IWUSR | S_IRUGO,
+ mmc_lockable_show, mmc_lockable_store);
+
+#endif
+

static void mmc_release_card(struct device *dev)
{
@@ -234,6 +329,11 @@ int mmc_register_card(struct mmc_card *c
if (ret)
device_del(&card->dev);
}
+#ifdef CONFIG_MMC_PASSWORDS
+ ret = device_create_file(&card->dev, &mmc_dev_attr_lockable);
+ if (ret)
+ device_del(&card->dev);
+#endif
}
return ret;
}
@@ -248,6 +348,9 @@ void mmc_remove_card(struct mmc_card *ca
if (mmc_card_sd(card))
device_remove_file(&card->dev, &mmc_dev_attr_scr);

+#ifdef CONFIG_MMC_PASSWORDS
+ device_remove_file(&card->dev, &mmc_dev_attr_lockable);
+#endif
device_del(&card->dev);
}


Attachments:
mmc_sysfs.diff (4.26 kB)

2007-01-03 12:02:49

by Anderson Briglia

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Implement MMC password force erase, remove password, change password,
unlock card and assign password operations. It uses the sysfs mechanism
to send commands to the MMC subsystem.

Signed-off-by: Carlos Eduardo Aguiar <[email protected]>
Signed-off-by: Anderson Lizardo <[email protected]>
Signed-off-by: Anderson Briglia <[email protected]>

Index: linux-linus-2.6/drivers/mmc/mmc_sysfs.c
===================================================================
--- linux-linus-2.6.orig/drivers/mmc/mmc_sysfs.c 2007-01-03 07:57:40.000000000 -0400
+++ linux-linus-2.6/drivers/mmc/mmc_sysfs.c 2007-01-03 07:58:14.000000000 -0400
@@ -17,6 +17,7 @@
#include <linux/idr.h>
#include <linux/workqueue.h>
#include <linux/key.h>
+#include <linux/err.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
@@ -65,6 +66,107 @@ static struct device_attribute mmc_dev_a

static struct device_attribute mmc_dev_attr_scr = MMC_ATTR_RO(scr);

+#ifdef CONFIG_MMC_PASSWORDS
+
+static ssize_t
+mmc_lockable_show(struct device *dev, struct device_attribute *att, char *buf)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+
+ if (!mmc_card_lockable(card))
+ return sprintf(buf, "unsupported\n");
+ else
+ return sprintf(buf, "%slocked\n", mmc_card_locked(card) ?
+ "" : "un");
+}
+
+/*
+ * implement MMC password functions: force erase, remove password, change
+ * password, unlock card and assign password.
+ */
+static ssize_t
+mmc_lockable_store(struct device *dev, struct device_attribute *att,
+ const char *data, size_t len)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+ int err;
+
+ err = mmc_card_claim_host(card);
+ if (err != MMC_ERR_NONE)
+ return -EINVAL;
+
+ err = mmc_card_lockable(card);
+ if (!err)
+ goto error;
+
+ if (mmc_card_locked(card) && !strncmp(data, "erase", 5)) {
+ /* forced erase only works while card is locked */
+ mmc_lock_unlock(card, NULL, MMC_LOCK_MODE_ERASE);
+ goto out;
+ } else if (!mmc_card_locked(card) && !strncmp(data, "remove", 6)) {
+ /* remove password only works while card is unlocked */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "remove");
+
+ if (!IS_ERR(mmc_key)) {
+ int err = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_CLR_PWD);
+ if (!err)
+ goto out;
+ } else
+ goto request_key_error;
+ } else if (!mmc_card_locked(card) && ((!strncmp(data, "assign", 6)) ||
+ (!strncmp(data, "change", 6)))) {
+
+ /* assign or change */
+ struct key *mmc_key;
+
+ if(!strncmp(data, "assign", 6))
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "assign");
+ else
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "change");
+
+ if (!IS_ERR(mmc_key)) {
+ int err = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_SET_PWD);
+ if (!err)
+ goto out;
+ } else
+ goto request_key_error;
+ } else if (mmc_card_locked(card) && !strncmp(data, "unlock", 6)) {
+ /* unlock */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "unlock");
+ if (!IS_ERR(mmc_key)) {
+ int err = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_UNLOCK);
+ if (err) {
+ dev_dbg(&card->dev, "Wrong password\n");
+ goto error;
+ }
+ else {
+ mmc_card_release_host(card);
+ goto out_unlocked;
+ }
+ } else
+ goto request_key_error;
+ }
+
+request_key_error:
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+error:
+ mmc_card_release_host(card);
+ return -EINVAL;
+out:
+ mmc_card_release_host(card);
+ return len;
+
+out_unlocked:
+ device_release_driver(dev);
+ device_attach(dev);
+ return len;
+}
+
+static struct device_attribute mmc_dev_attr_lockable =
+ __ATTR(lockable, S_IWUSR | S_IRUGO,
+ mmc_lockable_show, mmc_lockable_store);
+
+#endif

static void mmc_release_card(struct device *dev)
{
@@ -234,6 +336,11 @@ int mmc_register_card(struct mmc_card *c
if (ret)
device_del(&card->dev);
}
+#ifdef CONFIG_MMC_PASSWORDS
+ ret = device_create_file(&card->dev, &mmc_dev_attr_lockable);
+ if (ret)
+ device_del(&card->dev);
+#endif
}
return ret;
}
@@ -248,6 +355,9 @@ void mmc_remove_card(struct mmc_card *ca
if (mmc_card_sd(card))
device_remove_file(&card->dev, &mmc_dev_attr_scr);

+#ifdef CONFIG_MMC_PASSWORDS
+ device_remove_file(&card->dev, &mmc_dev_attr_lockable);
+#endif
device_del(&card->dev);
}


Attachments:
mmc_sysfs.diff (4.25 kB)

2007-01-06 13:35:46

by Pierre Ossman

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Anderson Briglia wrote:
> Hi all,
>
> I believe this code is following the latest Russel's comments.
>

Afraid not. mmc_card_claim_host() is incredibly unintuitive in that it
requires an unlock on error (the lock always succeeds, the card select
might fail). I'll fix that up and commit the patch set.

Rgds

--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org

2007-01-06 22:24:56

by Pierre Ossman

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

I've queued it up for -mm, but there a few more comments I want resolved
before this can move to Linus...

You need to clean up mmc_lockable_store(). It had a few broken variable
declarations that even prevented it from compiling, and after I fixed
that I still get:

drivers/mmc/mmc_sysfs.c: In function ?mmc_lockable_store?:
drivers/mmc/mmc_sysfs.c:160: warning: ignoring return value of
?device_attach?, declared with attribute warn_unused_result
drivers/mmc/mmc_sysfs.c:93: warning: ?mmc_key? may be used uninitialized
in this function

There's also no handling for an invalid string written to the sysfs node.

And third, you're a bit excessive on the goto:s. E.g. out_unlocked is
used in a single place, so it is completely unnecessary. Please do a
general cleanup of the control flow.

Rgds

--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org

2007-01-10 13:37:14

by Anderson Briglia

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

ext Pierre Ossman wrote:
> I've queued it up for -mm, but there a few more comments I want resolved
> before this can move to Linus...

Ok, thanks for the revisions.
>
> You need to clean up mmc_lockable_store(). It had a few broken variable
> declarations that even prevented it from compiling, and after I fixed
> that I still get:
>
> drivers/mmc/mmc_sysfs.c: In function ?mmc_lockable_store?:
> drivers/mmc/mmc_sysfs.c:160: warning: ignoring return value of
> ?device_attach?, declared with attribute warn_unused_result
> drivers/mmc/mmc_sysfs.c:93: warning: ?mmc_key? may be used uninitialized
> in this function

I did a modification at this patch and did not get those warnings anymore.
>
> There's also no handling for an invalid string written to the sysfs node.

Is this really needed? I thought the function just ignored other values sent to itself that were not handled.

>
> And third, you're a bit excessive on the goto:s. E.g. out_unlocked is
> used in a single place, so it is completely unnecessary. Please do a
> general cleanup of the control flow.

Ok.

Regards,

Anderson Briglia

2007-01-10 19:25:53

by Pierre Ossman

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Anderson Briglia wrote:
>> There's also no handling for an invalid string written to the sysfs node.
>>
>
> Is this really needed? I thought the function just ignored other values sent to itself that were not handled.
>
>

Well, returning an error on invalid data is the right<tm> thing to do.
And the warning about mmc_key is caused by this lack of error handling.

Rgds

--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org

2007-01-29 18:31:15

by Anderson Briglia

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Implement MMC password force erase, remove password, change password,
unlock card and assign password operations. It uses the sysfs mechanism
to send commands to the MMC subsystem.

Signed-off-by: Carlos Eduardo Aguiar <[email protected]>
Signed-off-by: Anderson Lizardo <[email protected]>
Signed-off-by: Anderson Briglia <[email protected]>

Index: linux-linus-2.6/drivers/mmc/mmc_sysfs.c
===================================================================
--- linux-linus-2.6.orig/drivers/mmc/mmc_sysfs.c 2007-01-29 14:26:21.000000000 -0400
+++ linux-linus-2.6/drivers/mmc/mmc_sysfs.c 2007-01-29 14:28:19.000000000 -0400
@@ -17,6 +17,7 @@
#include <linux/idr.h>
#include <linux/workqueue.h>
#include <linux/key.h>
+#include <linux/err.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
@@ -65,6 +66,102 @@ static struct device_attribute mmc_dev_a

static struct device_attribute mmc_dev_attr_scr = MMC_ATTR_RO(scr);

+#ifdef CONFIG_MMC_PASSWORDS
+
+static ssize_t
+mmc_lockable_show(struct device *dev, struct device_attribute *att, char *buf)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+
+ if (!mmc_card_lockable(card))
+ return sprintf(buf, "unsupported\n");
+ else
+ return sprintf(buf, "%slocked\n", mmc_card_locked(card) ?
+ "" : "un");
+}
+
+/*
+ * implement MMC password functions: force erase, remove password, change
+ * password, unlock card and assign password.
+ */
+static ssize_t
+mmc_lockable_store(struct device *dev, struct device_attribute *att,
+ const char *data, size_t len)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+ int ret;
+
+ ret = mmc_card_claim_host(card);
+ if ((ret != MMC_ERR_NONE) || (!mmc_card_lockable(card)))
+ return -EINVAL;
+
+ ret = -EINVAL;
+ if (mmc_card_locked(card) && !strncmp(data, "erase", 5)) {
+ /* forced erase only works while card is locked */
+ mmc_lock_unlock(card, NULL, MMC_LOCK_MODE_ERASE);
+ ret = len;
+ goto out;
+ } else if (!mmc_card_locked(card) && !strncmp(data, "remove", 6)) {
+ /* remove password only works while card is unlocked */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "remove");
+
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_CLR_PWD);
+ if (!ret) {
+ ret = len;
+ } goto out;
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (!mmc_card_locked(card) && ((!strncmp(data, "assign", 6)) ||
+ (!strncmp(data, "change", 6)))) {
+ /* assign or change */
+ struct key *mmc_key;
+
+ if(!(strncmp(data, "assign", 6)))
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "assign");
+ else
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "change");
+
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_SET_PWD);
+ if (!ret) {
+ ret = len;
+ goto out;
+ }
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (mmc_card_locked(card) && !strncmp(data, "unlock", 6)) {
+ /* unlock */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "unlock");
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_UNLOCK);
+ if (ret) {
+ dev_dbg(&card->dev, "Wrong password\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ else {
+ mmc_card_release_host(card);
+ device_release_driver(dev);
+ ret = device_attach(dev);
+ if(!ret)
+ return -EINVAL;
+ else
+ return len;
+ }
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ }
+out:
+ mmc_card_release_host(card);
+ return ret;
+}
+
+static struct device_attribute mmc_dev_attr_lockable =
+ __ATTR(lockable, S_IWUSR | S_IRUGO,
+ mmc_lockable_show, mmc_lockable_store);
+
+#endif

static void mmc_release_card(struct device *dev)
{
@@ -234,6 +331,11 @@ int mmc_register_card(struct mmc_card *c
if (ret)
device_del(&card->dev);
}
+#ifdef CONFIG_MMC_PASSWORDS
+ ret = device_create_file(&card->dev, &mmc_dev_attr_lockable);
+ if (ret)
+ device_del(&card->dev);
+#endif
}
return ret;
}
@@ -248,6 +350,9 @@ void mmc_remove_card(struct mmc_card *ca
if (mmc_card_sd(card))
device_remove_file(&card->dev, &mmc_dev_attr_scr);

+#ifdef CONFIG_MMC_PASSWORDS
+ device_remove_file(&card->dev, &mmc_dev_attr_lockable);
+#endif
device_del(&card->dev);
}


Attachments:
mmc_sysfs.diff (4.29 kB)

2007-01-30 18:10:56

by Pierre Ossman

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Anderson Briglia wrote:
> Hi Pierre,
>
> Sorry about the delay.
> I changed a bit the code to align with your latest suggestions.
>
>

Nice, but the locking is broken again.

> I believe now the number of goto's is ok.
>
>

Actually, the ones you have left are completely useless. So you can just
remove the last bunch aswell.

Rgds

--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org

2007-01-30 21:23:40

by Anderson Briglia

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Implement MMC password force erase, remove password, change password,
unlock card and assign password operations. It uses the sysfs mechanism
to send commands to the MMC subsystem.

Signed-off-by: Carlos Eduardo Aguiar <[email protected]>
Signed-off-by: Anderson Lizardo <[email protected]>
Signed-off-by: Anderson Briglia <[email protected]>

Index: linux-linus-2.6/drivers/mmc/mmc_sysfs.c
===================================================================
--- linux-linus-2.6.orig/drivers/mmc/mmc_sysfs.c 2007-01-30 16:28:38.000000000 -0400
+++ linux-linus-2.6/drivers/mmc/mmc_sysfs.c 2007-01-30 16:28:42.000000000 -0400
@@ -17,6 +17,7 @@
#include <linux/idr.h>
#include <linux/workqueue.h>
#include <linux/key.h>
+#include <linux/err.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
@@ -65,6 +66,100 @@ static struct device_attribute mmc_dev_a

static struct device_attribute mmc_dev_attr_scr = MMC_ATTR_RO(scr);

+#ifdef CONFIG_MMC_PASSWORDS
+
+static ssize_t
+mmc_lockable_show(struct device *dev, struct device_attribute *att, char *buf)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+
+ if (!mmc_card_lockable(card))
+ return sprintf(buf, "unsupported\n");
+ else
+ return sprintf(buf, "%slocked\n", mmc_card_locked(card) ?
+ "" : "un");
+}
+
+/*
+ * implement MMC password functions: force erase, remove password, change
+ * password, unlock card and assign password.
+ */
+static ssize_t
+mmc_lockable_store(struct device *dev, struct device_attribute *att,
+ const char *data, size_t len)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+ int ret;
+
+ if(!mmc_card_lockable(card))
+ return -EINVAL;
+
+ ret = mmc_card_claim_host(card);
+ if (ret != MMC_ERR_NONE)
+ return -EINVAL;
+
+ ret = -EINVAL;
+ if (mmc_card_locked(card) && !strncmp(data, "erase", 5)) {
+ /* forced erase only works while card is locked */
+ mmc_lock_unlock(card, NULL, MMC_LOCK_MODE_ERASE);
+ ret = len;
+ } else if (!mmc_card_locked(card) && !strncmp(data, "remove", 6)) {
+ /* remove password only works while card is unlocked */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "remove");
+
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_CLR_PWD);
+ if (!ret)
+ ret = len;
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (!mmc_card_locked(card) && ((!strncmp(data, "assign", 6)) ||
+ (!strncmp(data, "change", 6)))) {
+ /* assign or change */
+ struct key *mmc_key;
+
+ if(!(strncmp(data, "assign", 6)))
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "assign");
+ else
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "change");
+
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_SET_PWD);
+ if (!ret)
+ ret = len;
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (mmc_card_locked(card) && !strncmp(data, "unlock", 6)) {
+ /* unlock */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "unlock");
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_UNLOCK);
+ if (ret) {
+ dev_dbg(&card->dev, "Wrong password\n");
+ ret = -EINVAL;
+ }
+ else {
+ mmc_card_release_host(card);
+ device_release_driver(dev);
+ ret = device_attach(dev);
+ if(!ret)
+ return -EINVAL;
+ else
+ return len;
+ }
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ }
+
+ mmc_card_release_host(card);
+ return ret;
+}
+
+static struct device_attribute mmc_dev_attr_lockable =
+ __ATTR(lockable, S_IWUSR | S_IRUGO,
+ mmc_lockable_show, mmc_lockable_store);
+
+#endif

static void mmc_release_card(struct device *dev)
{
@@ -234,6 +329,11 @@ int mmc_register_card(struct mmc_card *c
if (ret)
device_del(&card->dev);
}
+#ifdef CONFIG_MMC_PASSWORDS
+ ret = device_create_file(&card->dev, &mmc_dev_attr_lockable);
+ if (ret)
+ device_del(&card->dev);
+#endif
}
return ret;
}
@@ -248,6 +348,9 @@ void mmc_remove_card(struct mmc_card *ca
if (mmc_card_sd(card))
device_remove_file(&card->dev, &mmc_dev_attr_scr);

+#ifdef CONFIG_MMC_PASSWORDS
+ device_remove_file(&card->dev, &mmc_dev_attr_lockable);
+#endif
device_del(&card->dev);
}


Attachments:
mmc_sysfs.diff (4.24 kB)

2007-02-03 14:45:24

by Pierre Ossman

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Anderson Briglia wrote:
> Hi Pierre,
>
> How about now? Is better?
>
>

Locking problem is still there. You need to unclaim the host even when
claim fails.

Rgds

--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org

2007-02-05 21:28:32

by Anderson Briglia

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Implement MMC password force erase, remove password, change password,
unlock card and assign password operations. It uses the sysfs mechanism
to send commands to the MMC subsystem.

Signed-off-by: Carlos Eduardo Aguiar <[email protected]>
Signed-off-by: Anderson Lizardo <[email protected]>
Signed-off-by: Anderson Briglia <[email protected]>

Index: linux-linus-2.6/drivers/mmc/mmc_sysfs.c
===================================================================
--- linux-linus-2.6.orig/drivers/mmc/mmc_sysfs.c 2007-02-05 17:32:05.000000000 -0400
+++ linux-linus-2.6/drivers/mmc/mmc_sysfs.c 2007-02-05 17:32:19.000000000 -0400
@@ -17,6 +17,7 @@
#include <linux/idr.h>
#include <linux/workqueue.h>
#include <linux/key.h>
+#include <linux/err.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
@@ -65,6 +66,102 @@ static struct device_attribute mmc_dev_a

static struct device_attribute mmc_dev_attr_scr = MMC_ATTR_RO(scr);

+#ifdef CONFIG_MMC_PASSWORDS
+
+static ssize_t
+mmc_lockable_show(struct device *dev, struct device_attribute *att, char *buf)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+
+ if (!mmc_card_lockable(card))
+ return sprintf(buf, "unsupported\n");
+ else
+ return sprintf(buf, "%slocked\n", mmc_card_locked(card) ?
+ "" : "un");
+}
+
+/*
+ * implement MMC password functions: force erase, remove password, change
+ * password, unlock card and assign password.
+ */
+static ssize_t
+mmc_lockable_store(struct device *dev, struct device_attribute *att,
+ const char *data, size_t len)
+{
+ struct mmc_card *card = dev_to_mmc_card(dev);
+ int ret;
+
+ if(!mmc_card_lockable(card))
+ return -EINVAL;
+
+ ret = mmc_card_claim_host(card);
+ if (ret != MMC_ERR_NONE) {
+ mmc_card_release_host(card);
+ return -EINVAL;
+ }
+
+ ret = -EINVAL;
+ if (mmc_card_locked(card) && !strncmp(data, "erase", 5)) {
+ /* forced erase only works while card is locked */
+ mmc_lock_unlock(card, NULL, MMC_LOCK_MODE_ERASE);
+ ret = len;
+ } else if (!mmc_card_locked(card) && !strncmp(data, "remove", 6)) {
+ /* remove password only works while card is unlocked */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "remove");
+
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_CLR_PWD);
+ if (!ret)
+ ret = len;
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (!mmc_card_locked(card) && ((!strncmp(data, "assign", 6)) ||
+ (!strncmp(data, "change", 6)))) {
+ /* assign or change */
+ struct key *mmc_key;
+
+ if(!(strncmp(data, "assign", 6)))
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "assign");
+ else
+ mmc_key = request_key(&mmc_key_type, "mmc:key", "change");
+
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_SET_PWD);
+ if (!ret)
+ ret = len;
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ } else if (mmc_card_locked(card) && !strncmp(data, "unlock", 6)) {
+ /* unlock */
+ struct key *mmc_key = request_key(&mmc_key_type, "mmc:key", "unlock");
+ if (!IS_ERR(mmc_key)) {
+ ret = mmc_lock_unlock(card, mmc_key, MMC_LOCK_MODE_UNLOCK);
+ if (ret) {
+ dev_dbg(&card->dev, "Wrong password\n");
+ ret = -EINVAL;
+ }
+ else {
+ mmc_card_release_host(card);
+ device_release_driver(dev);
+ ret = device_attach(dev);
+ if(!ret)
+ return -EINVAL;
+ else
+ return len;
+ }
+ } else
+ dev_dbg(&card->dev, "request_key returned error %ld\n", PTR_ERR(mmc_key));
+ }
+
+ mmc_card_release_host(card);
+ return ret;
+}
+
+static struct device_attribute mmc_dev_attr_lockable =
+ __ATTR(lockable, S_IWUSR | S_IRUGO,
+ mmc_lockable_show, mmc_lockable_store);
+
+#endif

static void mmc_release_card(struct device *dev)
{
@@ -234,6 +331,11 @@ int mmc_register_card(struct mmc_card *c
if (ret)
device_del(&card->dev);
}
+#ifdef CONFIG_MMC_PASSWORDS
+ ret = device_create_file(&card->dev, &mmc_dev_attr_lockable);
+ if (ret)
+ device_del(&card->dev);
+#endif
}
return ret;
}
@@ -248,6 +350,9 @@ void mmc_remove_card(struct mmc_card *ca
if (mmc_card_sd(card))
device_remove_file(&card->dev, &mmc_dev_attr_scr);

+#ifdef CONFIG_MMC_PASSWORDS
+ device_remove_file(&card->dev, &mmc_dev_attr_lockable);
+#endif
device_del(&card->dev);
}


Attachments:
mmc_sysfs.diff (4.28 kB)

2007-02-06 11:55:21

by Pierre Ossman

[permalink] [raw]
Subject: Re: [PATCH 4/4] Add MMC Password Protection (lock/unlock) support V9: mmc_sysfs.diff

Anderson Briglia wrote:
> Bug fixed. Is there anything else to improve?
>
>

Great. All known issues should be fixed now.

I'm currently reorganising my -mm branch, so things might go missing
from there for a while. But it will be back eventually.

Btw, any progress on testing this with SD?

Rgds

--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org