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

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

[Anderson Briglia]

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[-- Attachment #2: mmc_sysfs.diff --]
[-- Type: text/plain, Size: 4363 bytes --]

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);
 	}
 

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

[Anderson Briglia]

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Hi all,

I believe this code is following the latest Russel's comments.

Regards,

Anderson Briglia

---> cut here <----

[-- Attachment #2: mmc_sysfs.diff --]
[-- Type: text/plain, Size: 4351 bytes --]

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@indt.org.br>
Signed-off-by: Anderson Lizardo <anderson.lizardo@indt.org.br>
Signed-off-by: Anderson Briglia <anderson.briglia@indt.org.br>

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);
 	}
 

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

[Pierre Ossman]

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

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

[Pierre Ossman]

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

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

[Anderson Briglia]

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

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

[Pierre Ossman]

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

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

[Anderson Briglia]

[-- Attachment #1: Type: text/plain, Size: 1151 bytes --]

Hi Pierre,

Sorry about the delay.
I changed a bit the code to align with your latest suggestions.

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...
> 
> 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'm not getting those errors anymore.
> 
> There's also no handling for an invalid string written to the sysfs node.

I believe now it is ok. If you send an invalid string to sysfs it will return -EINVAL.
> 
> 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.

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

Regards,

Anderson Briglia

[-- Attachment #2: mmc_sysfs.diff --]
[-- Type: text/plain, Size: 4393 bytes --]

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@indt.org.br>
Signed-off-by: Anderson Lizardo <anderson.lizardo@indt.org.br>
Signed-off-by: Anderson Briglia <anderson.briglia@indt.org.br>

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);
 	}
 

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

[Pierre Ossman]

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

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

[Anderson Briglia]

[-- Attachment #1: Type: text/plain, Size: 462 bytes --]

Hi Pierre,

How about now? Is better?

Regards,

Anderson Briglia

ext Pierre Ossman wrote:
> 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
> 


[-- Attachment #2: mmc_sysfs.diff --]
[-- Type: text/plain, Size: 4340 bytes --]

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@indt.org.br>
Signed-off-by: Anderson Lizardo <anderson.lizardo@indt.org.br>
Signed-off-by: Anderson Briglia <anderson.briglia@indt.org.br>

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);
 	}
 

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

[Pierre Ossman]

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

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

[Anderson Briglia]

[-- Attachment #1: Type: text/plain, Size: 284 bytes --]

Hi Pierre,

ext Pierre Ossman wrote:
> 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.

Bug fixed. Is there anything else to improve?

Regards,

Anderson Briglia

[-- Attachment #2: mmc_sysfs.diff --]
[-- Type: text/plain, Size: 4378 bytes --]

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@indt.org.br>
Signed-off-by: Anderson Lizardo <anderson.lizardo@indt.org.br>
Signed-off-by: Anderson Briglia <anderson.briglia@indt.org.br>

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);
 	}
 

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

[Pierre Ossman]

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