1 files changed, 186 insertions, 0 deletions
diff --git a/arch/arm/mach-socfpga/secure_vab.c b/arch/arm/mach-socfpga/secure_vab.c
new file mode 100644
index 00000000000..e2db5885064
--- /dev/null
+++ b/arch/arm/mach-socfpga/secure_vab.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Intel Corporation <www.intel.com>
+ *
+ */
+
+#include <asm/arch/mailbox_s10.h>
+#include <asm/arch/secure_vab.h>
+#include <asm/arch/smc_api.h>
+#include <asm/unaligned.h>
+#include <common.h>
+#include <exports.h>
+#include <linux/errno.h>
+#include <linux/intel-smc.h>
+#include <log.h>
+
+#define CHUNKSZ_PER_WD_RESET		(256 * SZ_1K)
+
+/*
+ * Read the length of the VAB certificate from the end of image
+ * and calculate the actual image size (excluding the VAB certificate).
+ */
+static size_t get_img_size(u8 *img_buf, size_t img_buf_sz)
+{
+	u8 *img_buf_end = img_buf + img_buf_sz;
+	u32 cert_sz = get_unaligned_le32(img_buf_end - sizeof(u32));
+	u8 *p = img_buf_end - cert_sz - sizeof(u32);
+
+	/* Ensure p is pointing within the img_buf */
+	if (p < img_buf || p > (img_buf_end - VAB_CERT_HEADER_SIZE))
+		return 0;
+
+	if (get_unaligned_le32(p) == SDM_CERT_MAGIC_NUM)
+		return (size_t)(p - img_buf);
+
+	return 0;
+}
+
+/*
+ * Vendor Authorized Boot (VAB) is a security feature for authenticating
+ * the images such as U-Boot, ARM trusted Firmware, Linux kernel,
+ * device tree blob and etc loaded from FIT. User can also trigger
+ * the VAB authentication from U-Boot command.
+ *
+ * This function extracts the VAB certificate and signature block
+ * appended at the end of the image, then send to Secure Device Manager
+ * (SDM) for authentication. This function will validate the SHA384
+ * of the image against the SHA384 hash stored in the VAB certificate
+ * before sending the VAB certificate to SDM for authentication.
+ *
+ * RETURN
+ * 0 if authentication success or
+ *   if authentication is not required and bypassed on a non-secure device
+ * negative error code if authentication fail
+ */
+int socfpga_vendor_authentication(void **p_image, size_t *p_size)
+{
+	int retry_count = 20;
+	u8 hash384[SHA384_SUM_LEN];
+	u64 img_addr, mbox_data_addr;
+	size_t img_sz, mbox_data_sz;
+	u8 *cert_hash_ptr, *mbox_relocate_data_addr;
+	u32 resp = 0, resp_len = 1;
+	int ret;
+
+	img_addr = (uintptr_t)*p_image;
+
+	debug("Authenticating image at address 0x%016llx (%ld bytes)\n",
+	      img_addr, *p_size);
+
+	img_sz = get_img_size((u8 *)img_addr, *p_size);
+	debug("img_sz = %ld\n", img_sz);
+
+	if (!img_sz) {
+		puts("VAB certificate not found in image!\n");
+		return -ENOKEY;
+	}
+
+	if (!IS_ALIGNED(img_sz, sizeof(u32))) {
+		printf("Image size (%ld bytes) not aliged to 4 bytes!\n",
+		       img_sz);
+		return -EBFONT;
+	}
+
+	/* Generate HASH384 from the image */
+	sha384_csum_wd((u8 *)img_addr, img_sz, hash384, CHUNKSZ_PER_WD_RESET);
+
+	cert_hash_ptr = (u8 *)(img_addr + img_sz + VAB_CERT_MAGIC_OFFSET +
+			       VAB_CERT_FIT_SHA384_OFFSET);
+
+	/*
+	 * Compare the SHA384 found in certificate against the SHA384
+	 * calculated from image
+	 */
+	if (memcmp(hash384, cert_hash_ptr, SHA384_SUM_LEN)) {
+		puts("SHA384 not match!\n");
+		return -EKEYREJECTED;
+	}
+
+	mbox_data_addr = img_addr + img_sz - sizeof(u32);
+	/* Size in word (32bits) */
+	mbox_data_sz = (ALIGN(*p_size - img_sz, sizeof(u32))) >> 2;
+
+	debug("mbox_data_addr = 0x%016llx\n", mbox_data_addr);
+	debug("mbox_data_sz = %ld words\n", mbox_data_sz);
+
+	/*
+	 * Relocate certificate to first memory block before trigger SMC call
+	 * to send mailbox command because ATF only able to access first
+	 * memory block.
+	 */
+	mbox_relocate_data_addr = (u8 *)malloc(mbox_data_sz * sizeof(u32));
+	if (!mbox_relocate_data_addr) {
+		puts("Out of memory for VAB certificate relocation!\n");
+		return -ENOMEM;
+	}
+
+	memcpy(mbox_relocate_data_addr, (u8 *)mbox_data_addr, mbox_data_sz * sizeof(u32));
+	*(u32 *)mbox_relocate_data_addr = 0;
+
+	debug("mbox_relocate_data_addr = 0x%p\n", mbox_relocate_data_addr);
+
+	do {
+		if (!IS_ENABLED(CONFIG_SPL_BUILD) && IS_ENABLED(CONFIG_SPL_ATF)) {
+			/* Invoke SMC call to ATF to send the VAB certificate to SDM */
+			ret  = smc_send_mailbox(MBOX_VAB_SRC_CERT, mbox_data_sz,
+						(u32 *)mbox_relocate_data_addr, 0, &resp_len,
+						&resp);
+		} else {
+			/* Send the VAB certficate to SDM for authentication */
+			ret = mbox_send_cmd(MBOX_ID_UBOOT, MBOX_VAB_SRC_CERT,
+					    MBOX_CMD_DIRECT, mbox_data_sz,
+					    (u32 *)mbox_relocate_data_addr, 0, &resp_len,
+					    &resp);
+		}
+		/* If SDM is not available, just delay 50ms and retry again */
+		if (ret == MBOX_RESP_DEVICE_BUSY)
+			mdelay(50);
+		else
+			break;
+	} while (--retry_count);
+
+	/* Free the relocate certificate memory space */
+	free(mbox_relocate_data_addr);
+
+	/* Exclude the size of the VAB certificate from image size */
+	*p_size = img_sz;
+
+	debug("ret = 0x%08x, resp = 0x%08x, resp_len = %d\n", ret, resp,
+	      resp_len);
+
+	if (ret) {
+		/*
+		 * Unsupported mailbox command or device not in the
+		 * owned/secure state
+		 */
+		if (ret == MBOX_RESP_NOT_ALLOWED_UNDER_SECURITY_SETTINGS) {
+			/* SDM bypass authentication */
+			printf("%s 0x%016llx (%ld bytes)\n",
+			       "Image Authentication bypassed at address",
+			       img_addr, img_sz);
+			return 0;
+		}
+		puts("VAB certificate authentication failed in SDM");
+		if (ret == MBOX_RESP_DEVICE_BUSY) {
+			puts(" (SDM busy timeout)\n");
+			return -ETIMEDOUT;
+		} else if (ret == MBOX_RESP_UNKNOWN) {
+			puts(" (Not supported)\n");
+			return -ESRCH;
+		}
+		puts("\n");
+		return -EKEYREJECTED;
+	} else {
+		/* If Certificate Process Status has error */
+		if (resp) {
+			puts("VAB certificate process failed\n");
+			return -ENOEXEC;
+		}
+	}
+
+	printf("%s 0x%016llx (%ld bytes)\n",
+	       "Image Authentication passed at address", img_addr, img_sz);
+
+	return 0;
+}