[v7,3/3] SMAF: add fake secure module

Message ID 1462806459-8124-4-git-send-email-benjamin.gaignard@linaro.org
State Superseded
Headers show

Commit Message

Benjamin Gaignard May 9, 2016, 3:07 p.m.
This module is allow testing secure calls of SMAF.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
---
 drivers/smaf/Kconfig           |  6 +++
 drivers/smaf/Makefile          |  1 +
 drivers/smaf/smaf-fakesecure.c | 85 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+)
 create mode 100644 drivers/smaf/smaf-fakesecure.c

Comments

Benjamin Gaignard May 17, 2016, 3:17 p.m. | #1
2016-05-17 1:10 GMT+02:00 Emil Velikov <emil.l.velikov@gmail.com>:
> Hi Benjamin,
>
> On 9 May 2016 at 16:07, Benjamin Gaignard <benjamin.gaignard@linaro.org> wrote:
>> This module is allow testing secure calls of SMAF.
>>
> "Add fake secure module" does sound like something not (m)any people
> want to hear ;-)
> Have you considered calling it 'dummy', 'test' or similar ?

"test" is better name, I will change to that

>
>
>> --- /dev/null
>> +++ b/drivers/smaf/smaf-fakesecure.c
>> @@ -0,0 +1,85 @@
>> +/*
>> + * smaf-fakesecure.c
>> + *
>> + * Copyright (C) Linaro SA 2015
>> + * Author: Benjamin Gaignard <benjamin.gaignard@linaro.org> for Linaro.
>> + * License terms:  GNU General Public License (GPL), version 2
>> + */
>> +#include <linux/module.h>
>> +#include <linux/slab.h>
>> +#include <linux/smaf-secure.h>
>> +
>> +#define MAGIC 0xDEADBEEF
>> +
>> +struct fake_private {
>> +       int magic;
>> +};
>> +
>> +static void *smaf_fakesecure_create(void)
>> +{
>> +       struct fake_private *priv;
>> +
>> +       priv = kzalloc(sizeof(*priv), GFP_KERNEL);
> Missing ENOMEM handling ?
>
>> +       priv->magic = MAGIC;
>> +
>> +       return priv;
>> +}
>> +
>> +static int smaf_fakesecure_destroy(void *ctx)
>> +{
>> +       struct fake_private *priv = (struct fake_private *)ctx;
> You might want to flesh this cast into a (inline) helper and use it throughout ?
>
>
> ... and that is all. Hope these were useful, or at the very least not
> utterly wrong, suggestions :-)
>
>
> Regards,
> Emil
>
> P.S. From a quick look userspace has some subtle bugs/odd practises.
> Let me know if you're interested in my input.

Your advices are welcome for userspace too

Thanks
Benjamin

Patch

diff --git a/drivers/smaf/Kconfig b/drivers/smaf/Kconfig
index 058ec4c..fd17005 100644
--- a/drivers/smaf/Kconfig
+++ b/drivers/smaf/Kconfig
@@ -9,3 +9,9 @@  config SMAF_CMA
 	depends on SMAF && HAVE_DMA_ATTRS
 	help
 	  Choose this option to enable CMA allocation within SMAF
+
+config SMAF_FAKE_SECURE
+	tristate "SMAF fake secure module"
+	depends on SMAF
+	help
+	  Choose this option to enable fake secure module for test purpose
diff --git a/drivers/smaf/Makefile b/drivers/smaf/Makefile
index 05bab01b..00d5cd4 100644
--- a/drivers/smaf/Makefile
+++ b/drivers/smaf/Makefile
@@ -1,2 +1,3 @@ 
 obj-$(CONFIG_SMAF) += smaf-core.o
 obj-$(CONFIG_SMAF_CMA) += smaf-cma.o
+obj-$(CONFIG_SMAF_FAKE_SECURE) += smaf-fakesecure.o
diff --git a/drivers/smaf/smaf-fakesecure.c b/drivers/smaf/smaf-fakesecure.c
new file mode 100644
index 0000000..5f3d355
--- /dev/null
+++ b/drivers/smaf/smaf-fakesecure.c
@@ -0,0 +1,85 @@ 
+/*
+ * smaf-fakesecure.c
+ *
+ * Copyright (C) Linaro SA 2015
+ * Author: Benjamin Gaignard <benjamin.gaignard@linaro.org> for Linaro.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/smaf-secure.h>
+
+#define MAGIC 0xDEADBEEF
+
+struct fake_private {
+	int magic;
+};
+
+static void *smaf_fakesecure_create(void)
+{
+	struct fake_private *priv;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	priv->magic = MAGIC;
+
+	return priv;
+}
+
+static int smaf_fakesecure_destroy(void *ctx)
+{
+	struct fake_private *priv = (struct fake_private *)ctx;
+
+	WARN_ON(!priv || (priv->magic != MAGIC));
+	kfree(priv);
+
+	return 0;
+}
+
+static bool smaf_fakesecure_grant_access(void *ctx,
+					 struct device *dev,
+					 size_t addr, size_t size,
+					 enum dma_data_direction direction)
+{
+	struct fake_private *priv = (struct fake_private *)ctx;
+
+	WARN_ON(!priv || (priv->magic != MAGIC));
+	pr_debug("grant requested by device %s\n",
+		 dev->driver ? dev->driver->name : "cpu");
+
+	return priv->magic == MAGIC;
+}
+
+static void smaf_fakesecure_revoke_access(void *ctx,
+					  struct device *dev,
+					  size_t addr, size_t size,
+					  enum dma_data_direction direction)
+{
+	struct fake_private *priv = (struct fake_private *)ctx;
+
+	WARN_ON(!priv || (priv->magic != MAGIC));
+	pr_debug("revoke requested by device %s\n",
+		 dev->driver ? dev->driver->name : "cpu");
+}
+
+static struct smaf_secure fake = {
+	.create_ctx = smaf_fakesecure_create,
+	.destroy_ctx = smaf_fakesecure_destroy,
+	.grant_access = smaf_fakesecure_grant_access,
+	.revoke_access = smaf_fakesecure_revoke_access,
+};
+
+static int __init smaf_fakesecure_init(void)
+{
+	return smaf_register_secure(&fake);
+}
+module_init(smaf_fakesecure_init);
+
+static void __exit smaf_fakesecure_deinit(void)
+{
+	smaf_unregister_secure(&fake);
+}
+module_exit(smaf_fakesecure_deinit);
+
+MODULE_DESCRIPTION("SMAF fake secure module for test purpose");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@linaro.org>");