imx: hab: Check if CSF is valid before authenticating image

For proper authentication the HAB code must check if the CSF is valid.
Users must call the csf_is_valid() function to parse the CSF prior to
authenticating any additional images. The function will return a failure
if any of the following invalid conditions are met:

- CSF pointer is NULL
- CSF Header does not exist
- CSF does not lie within the image bounds
- CSF command length zero

Signed-off-by: Utkarsh Gupta <utkarsh.gupta@nxp.com>
Signed-off-by: Breno Lima <breno.lima@nxp.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/arm/include/asm/mach-imx/hab.h b/arch/arm/include/asm/mach-imx/hab.h
index a0cb19db2f..bb732030e9 100644
--- a/arch/arm/include/asm/mach-imx/hab.h
+++ b/arch/arm/include/asm/mach-imx/hab.h
@@ -38,6 +38,12 @@ struct ivt {
 	uint32_t reserved2;	/* Reserved should be zero */
 };
 
+struct __packed hab_hdr {
+	u8 tag;              /* Tag field */
+	u8 len[2];           /* Length field in bytes (big-endian) */
+	u8 par;              /* Parameters field */
+};
+
 /* -------- start of HAB API updates ------------*/
 /* The following are taken from HAB4 SIS */
 
@@ -182,6 +188,8 @@ typedef void hapi_clock_init_t(void);
 #define HAB_CID_ROM 0 /**< ROM Caller ID */
 #define HAB_CID_UBOOT 1 /**< UBOOT Caller ID*/
 
+#define HAB_CMD_HDR          0xD4  /* CSF Header */
+
 #define IVT_SIZE			0x20
 #define CSF_PAD_SIZE			0x2000