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Commit 97e4a55c authored by Shivaprasad Hongal's avatar Shivaprasad Hongal
Browse files

pfk_ice: Check km version before ICE calls 



Check the keymaster version to decide where the wrapped
keys are unwrapped.

Change-Id: Id91bfd33d9719d99de5e5cf39938bc148de7da5c
Signed-off-by: default avatarShivaprasad Hongal <shongal@codeaurora.org>
parent 4f5a0984

security/pfe/pfk_ice.c

+72 −12
Original line number Diff line number Diff line
@@ -58,38 +58,98 @@ 
#define CONTEXT_SIZE 0x1000



#define KEYMASTER_UTILS_CMD_ID 0x200UL

#define KEYMASTER_GET_VERSION (KEYMASTER_UTILS_CMD_ID + 0UL)

#define KEYMASTER_SET_ICE_KEY (KEYMASTER_UTILS_CMD_ID + 18UL)

#define KEYMASTER_CLEAR_ICE_KEY (KEYMASTER_UTILS_CMD_ID + 19UL)



#define USE_KM_MAJOR_VERSION 4

#define USE_KM_MINOR_VERSION 513



#define ICE_KEY_SIZE 32

#define ICE_SALT_SIZE 32



static uint32_t keymaster_minor_version;

static uint32_t keymaster_major_version;



static uint8_t ice_key[ICE_KEY_SIZE];

static uint8_t ice_salt[ICE_KEY_SIZE];



static struct qseecom_handle *qhandle;



static int set_wrapped_key(uint32_t index, const uint8_t *key,

				const uint8_t *salt)

static uint32_t get_keymaster_version(struct qseecom_handle *qhandle)

{

	int ret = 0;

	u32 set_req_len = 0;

	u32 set_rsp_len = 0;

	struct pfk_ice_key_req *set_req_buf;

	struct pfk_ice_key_rsp *set_rsp_buf;

	struct pfk_km_get_version_req *req;

	struct pfk_km_get_version_rsp *rsp;



	memcpy(ice_key, key, sizeof(ice_key));

	memcpy(ice_salt, salt, sizeof(ice_salt));

	req = (struct pfk_km_get_version_req *) qhandle->sbuf;

	req->cmd_id = KEYMASTER_GET_VERSION;



	rsp = (struct pfk_km_get_version_rsp *) (qhandle->sbuf

		+ sizeof(struct pfk_km_get_version_req));



	ret = qseecom_send_command(qhandle,

			req, sizeof(struct pfk_km_get_version_req),

			rsp, sizeof(struct pfk_km_get_version_rsp));



	if (ret) {

		pr_err("%s: Get KM version error: Status %d\n", __func__,

						rsp->status);

		return ret;

	}



	keymaster_major_version = rsp->ta_major_version;

	keymaster_minor_version = rsp->ta_minor_version;



	return ret;

}



/*

 * This change is to make sure there are no issues when pfk calls into

 * keymaster for unwrapping keys before setting them. This can happen when

 * an older version of keymaster is used which means the unwrapping logic

 * cannot be done in trustzone.

 */



static bool should_use_keymaster(void)

{

	int ret = -1;

	if (!qhandle) {

		ret = qseecom_start_app(&qhandle, "keymaster64",

			CONTEXT_SIZE);

		if (ret) {

			pr_err("Qseecom start app failed\n");

			return ret;

			return false;

		}

	}



	if (keymaster_major_version == 0 || keymaster_minor_version == 0) {

		ret = get_keymaster_version(qhandle);

		if (ret) {

			pr_err("Error in getting keymaster version\n");

			return false;

		}

	}



	if (keymaster_major_version == USE_KM_MAJOR_VERSION &&

			keymaster_minor_version < USE_KM_MINOR_VERSION)

		return true;

	else

		return false;

}



static int set_wrapped_key(uint32_t index, const uint8_t *key,

				const uint8_t *salt)

{

	int ret = 0;

	u32 set_req_len = 0;

	u32 set_rsp_len = 0;

	struct pfk_ice_key_req *set_req_buf;

	struct pfk_ice_key_rsp *set_rsp_buf;



	memcpy(ice_key, key, sizeof(ice_key));

	memcpy(ice_salt, salt, sizeof(ice_salt));



	set_req_buf = (struct pfk_ice_key_req *) qhandle->sbuf;

	set_req_buf->cmd_id = KEYMASTER_SET_ICE_KEY;

	set_req_buf->index = index;
@@ -232,7 +292,7 @@ int qti_pfk_ice_set_key(uint32_t index, uint8_t *key, uint8_t *salt, 
		goto out;

	}



	if (pfk_wrapped_key_supported()) {

	if (pfk_wrapped_key_supported() && should_use_keymaster()) {

		pr_debug("%s: Setting wrapped key\n", __func__);

		ret = set_wrapped_key(index, key, salt);

	} else {
@@ -248,7 +308,7 @@ int qti_pfk_ice_set_key(uint32_t index, uint8_t *key, uint8_t *salt, 
				goto out;

		}

		/* Try to invalidate the key to keep ICE in proper state */

		if (pfk_wrapped_key_supported())

		if (pfk_wrapped_key_supported() && should_use_keymaster())

			ret1 = clear_wrapped_key(index);

		else

			ret1 = clear_key(index);
@@ -285,7 +345,7 @@ int qti_pfk_ice_invalidate_key(uint32_t index, char *storage_type) 
		return ret;

	}



	if (pfk_wrapped_key_supported()) {

	if (pfk_wrapped_key_supported() && should_use_keymaster()) {

		ret = clear_wrapped_key(index);

		pr_debug("%s: Clearing wrapped key\n", __func__);

	} else {

security/pfe/pfk_ice.h

+16 −4
Original line number Diff line number Diff line
@@ -22,19 +22,31 @@ 


#include <linux/types.h>



struct __attribute__ ((__packed__)) pfk_ice_key_req {

struct pfk_ice_key_req {

	uint32_t cmd_id;

	uint32_t index;

	uint32_t ice_key_offset;

	uint32_t ice_key_size;

	uint32_t ice_salt_offset;

	uint32_t ice_salt_size;

};

} __packed;



struct __attribute__ ((__packed__)) pfk_ice_key_rsp {

struct pfk_ice_key_rsp {

	uint32_t ret;

	uint32_t cmd_id;

};

} __packed;



struct pfk_km_get_version_req {

	uint32_t cmd_id;

} __packed;



struct pfk_km_get_version_rsp {

	int status;

	uint32_t major_version;

	uint32_t minor_version;

	uint32_t ta_major_version;

	uint32_t ta_minor_version;

} __packed;



int pfk_ice_init(void);

int pfk_ice_deinit(void);