TBB: add non-volatile counter support

This patch adds support for non-volatile counter authentication to
the Authentication Module. This method consists of matching the
counter values provided in the certificates with the ones stored
in the platform. If the value from the certificate is lower than
the platform, the boot process is aborted. This mechanism protects
the system against rollback.

The TBBR CoT has been updated to include this method as part of the
authentication process. Two counters are used: one for the trusted
world images and another for the non trusted world images.

** NEW PLATFORM APIs (mandatory when TBB is enabled) **

int plat_get_nv_ctr(void *cookie, unsigned int *nv_ctr);

    This API returns the non-volatile counter value stored
    in the platform. The cookie in the first argument may be
    used to select the counter in case the platform provides
    more than one (i.e. TBSA compliant platforms must provide
    trusted and non-trusted counters). This cookie is specified
    in the CoT.

int plat_set_nv_ctr(void *cookie, unsigned int nv_ctr);

    This API sets a new counter value. The cookie may be
    used to select the counter to be updated.

An implementation of these new APIs for ARM platforms is also
provided. The values are obtained from the Trusted Non-Volatile
Counters peripheral. The cookie is used to pass the extension OID.
This OID may be interpreted by the platform to know which counter
must return. On Juno, The trusted and non-trusted counter values
have been tied to 31 and 223, respectively, and cannot be modified.

** IMPORTANT **

THIS PATCH BREAKS THE BUILD WHEN TRUSTED_BOARD_BOOT IS ENABLED. THE
NEW PLATFORM APIs INTRODUCED IN THIS PATCH MUST BE IMPLEMENTED IN
ORDER TO SUCCESSFULLY BUILD TF.

Change-Id: Ic943b76b25f2a37f490eaaab6d87b4a8b3cbc89a

3 files changed, 13 insertions, 1 deletions

diff --git a/include/drivers/auth/auth_common.h b/include/drivers/auth/auth_common.h
index 52a895e4..456f69f2 100644
--- a/include/drivers/auth/auth_common.h
+++ b/include/drivers/auth/auth_common.h
@@ -46,6 +46,7 @@ typedef enum auth_param_type_enum {
 	AUTH_PARAM_SIG_ALG,		/* The image signature algorithm */
 	AUTH_PARAM_HASH,		/* A hash (including the algorithm) */
 	AUTH_PARAM_PUB_KEY,		/* A public key */
+	AUTH_PARAM_NV_CTR,		/* A non-volatile counter */
 } auth_param_type_t;
 
 /*
@@ -80,6 +81,7 @@ typedef enum auth_method_type_enum {
 	AUTH_METHOD_NONE = 0,
 	AUTH_METHOD_HASH,	/* Authenticate by hash matching */
 	AUTH_METHOD_SIG,	/* Authenticate by PK operation */
+	AUTH_METHOD_NV_CTR,	/* Authenticate by Non-Volatile Counter */
 	AUTH_METHOD_NUM 	/* Number of methods */
 } auth_method_type_t;
 
@@ -105,7 +107,8 @@ typedef struct auth_method_param_sig_s {
  * Parameters for authentication by NV counter
  */
 typedef struct auth_method_param_nv_ctr_s {
-	auth_param_type_desc_t *nv_ctr;	/* NV counter value */
+	auth_param_type_desc_t *cert_nv_ctr;	/* NV counter in certificate */
+	auth_param_type_desc_t *plat_nv_ctr;	/* NV counter in platform */
 } auth_method_param_nv_ctr_t;
 
 /*
diff --git a/include/plat/arm/soc/common/soc_css_def.h b/include/plat/arm/soc/common/soc_css_def.h
index 428df4d2..f1396a6c 100644
--- a/include/plat/arm/soc/common/soc_css_def.h
+++ b/include/plat/arm/soc/common/soc_css_def.h
@@ -65,6 +65,13 @@
  */
 #define SOC_CSS_NIC400_APB4_BRIDGE	4
 
+/* Non-volatile counters */
+#define SOC_TRUSTED_NVCTR_BASE		0x7fe70000
+#define TFW_NVCTR_BASE			(SOC_TRUSTED_NVCTR_BASE + 0x0000)
+#define TFW_NVCTR_SIZE			4
+#define NTFW_CTR_BASE			(SOC_TRUSTED_NVCTR_BASE + 0x0004)
+#define NTFW_CTR_SIZE			4
+
 /* Keys */
 #define SOC_KEYS_BASE			0x7fe80000
 #define TZ_PUB_KEY_HASH_BASE		(SOC_KEYS_BASE + 0x0000)
diff --git a/include/plat/common/platform.h b/include/plat/common/platform.h
index 5c61f381..f4d91df3 100644
--- a/include/plat/common/platform.h
+++ b/include/plat/common/platform.h
@@ -249,6 +249,8 @@ void bl32_plat_enable_mmu(uint32_t flags);
  ******************************************************************************/
 int plat_get_rotpk_info(void *cookie, void **key_ptr, unsigned int *key_len,
 			unsigned int *flags);
+int plat_get_nv_ctr(void *cookie, unsigned int *nv_ctr);
+int plat_set_nv_ctr(void *cookie, unsigned int nv_ctr);
 
 #if ENABLE_PLAT_COMPAT
 /*