Add command line tool to generate otp.bin

Author: danielinux

.gitignore

@@ -75,6 +75,9 @@ tools/keytools/otp/otp-keystore-primer
 tools/delta/bmdiff
 tools/delta/bmpatch
 
+# otp-keystore-gen binary
+tools/keytools/otp/otp-keystore-gen
+
 # Vim swap files
 .*.swp
 

Makefile

@@ -377,6 +377,9 @@ cppcheck:
 
 otp: tools/keytools/otp/otp-keystore-primer.bin FORCE
 
+otpgen:
+	make -C tools/keytools/otp otp-keystore-gen
+
 tools/keytools/otp/otp-keystore-primer.bin: FORCE
 	make -C tools/keytools/otp clean
 	make -C tools/keytools/otp

include/otp_keystore.h

@@ -34,8 +34,6 @@
     #include "hal/stm32h7.h"
 #elif defined TARGET_stm32h5
     #include "hal/stm32h5.h"
-#else
-    #error "Unsupported target for OTP"
 #endif
 
 #include "keystore.h"

tools/keytools/otp/Makefile

@@ -32,6 +32,12 @@ CC=$(CROSS_COMPILE)gcc
 OBJCOPY?=$(CROSS_COMPILE)objcopy
 SIZE?=$(CROSS_COMPILE)size
 
+all: otp-keystore-primer.bin otp-keystore-gen
+
+otp-keystore-gen: otp-keystore-gen.c ../../../src/keystore.c
+	gcc -o $@ $^ -I. -I../../../ -I../../../include -DFLASH_OTP_KEYSTORE
+
+
 otp-keystore-primer.bin: otp-keystore-primer.elf
 	$(Q)$(OBJCOPY) -O binary $(^) $(@)
 

tools/keytools/otp/otp-keystore-gen.c

@@ -0,0 +1,89 @@
+/* otp-keystore-primer.c
+ *
+ * Command line utility to create a OTP image
+ *
+ *
+ * Copyright (C) 2024 wolfSSL Inc.
+ *
+ * This file is part of wolfBoot.
+ *
+ * wolfBoot is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfBoot is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
+ */
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+
+#define OTP_SIZE 4096
+
+#include "wolfboot/wolfboot.h"
+#include "keystore.h"
+#include "otp_keystore.h"
+
+extern struct keystore_slot PubKeys[];
+
+const char outfile[] = "otp.bin";
+
+int main(void)
+{
+    int n_keys = keystore_num_pubkeys();
+    int i;
+    struct wolfBoot_otp_hdr hdr;
+    uint32_t tot_len;
+    int ofd;
+    int slot_size;
+
+    memcpy(hdr.keystore_hdr_magic, KEYSTORE_HDR_MAGIC, 8);
+    hdr.item_count = n_keys;
+    hdr.flags = 0;
+    hdr.version = WOLFBOOT_VERSION;
+
+    /* Sanity check to avoid writing an empty keystore */
+    if (n_keys < 1) {
+        fprintf(stderr, "Error: too few keys (%d), refusing to create %s\n", n_keys, outfile);
+        exit(1);
+    }
+    
+    slot_size = keystore_get_size(0);
+    slot_size += KEYSTORE_HDR_SIZE;
+    fprintf(stderr, "Slot size: %d\n", slot_size);
+
+    ofd = open(outfile, O_WRONLY|O_CREAT|O_TRUNC, 0600);
+    if (ofd < 0) {
+        perror("opening output file");
+        exit(2);
+    }
+     
+    /* Write the header to the beginning of the OTP binary file */
+    if (write(ofd, &hdr, sizeof(hdr)) != sizeof(hdr)) {
+        fprintf(stderr, "Error writing to %s: %s\n", outfile, strerror(errno));
+    }
+
+    for (i = 0; i < n_keys; i++) {
+        /* Write each public key to its slot in OTP */
+        if (write(ofd, &PubKeys[i],
+                slot_size) < 0) {
+        fprintf(stderr, "Error adding key %d to %s: %s\n", i, outfile, strerror(errno));
+        exit(3);
+        }
+    }
+    fprintf(stderr, "%s successfully created.\nGoodbye.\n", outfile);
+    close(ofd);
+    return 0;
+}