From a95a41b3e12781b8c99cd429e0a3801847455348 Mon Sep 17 00:00:00 2001
From: Marek Pieta <Marek.Pieta@nordicsemi.no>
Date: Fri, 21 Apr 2023 14:03:19 +0200
Subject: [PATCH] boot: bootutil: loader: Let image version comparison use
 build number

Change allows using build number in image version comparison.

Signed-off-by: Marek Pieta <Marek.Pieta@nordicsemi.no>
---
 boot/bootutil/src/loader.c                    | 22 ++++++++++++++-----
 boot/zephyr/Kconfig                           |  9 ++++++++
 .../include/mcuboot_config/mcuboot_config.h   |  4 ++++
 3 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/boot/bootutil/src/loader.c b/boot/bootutil/src/loader.c
index b49de922..311e72e1 100644
--- a/boot/bootutil/src/loader.c
+++ b/boot/bootutil/src/loader.c
@@ -622,15 +622,17 @@ boot_check_header_erased(struct boot_loader_state *state, int slot)
     defined(MCUBOOT_RAM_LOAD) || \
     defined(MCUBOOT_DOWNGRADE_PREVENTION)
 /**
- * Compare image version numbers not including the build number
+ * Compare image version numbers
+ *
+ * By default, the comparison does not take build number into account.
+ * Enable MCUBOOT_VERSION_CMP_USE_BUILD_NUMBER to take the build number into account.
  *
  * @param ver1           Pointer to the first image version to compare.
  * @param ver2           Pointer to the second image version to compare.
  *
- * @retval -1           If ver1 is strictly less than ver2.
- * @retval 0            If the image version numbers are equal,
- *                      (not including the build number).
- * @retval 1            If ver1 is strictly greater than ver2.
+ * @retval -1           If ver1 is less than ver2.
+ * @retval 0            If the image version numbers are equal.
+ * @retval 1            If ver1 is greater than ver2.
  */
 static int
 boot_version_cmp(const struct image_version *ver1,
@@ -657,6 +659,16 @@ boot_version_cmp(const struct image_version *ver1,
         return -1;
     }
 
+#if defined(MCUBOOT_VERSION_CMP_USE_BUILD_NUMBER)
+    /* The revisions are equal, continue comparison. */
+    if (ver1->iv_build_num > ver2->iv_build_num) {
+        return 1;
+    }
+    if (ver1->iv_build_num < ver2->iv_build_num) {
+        return -1;
+    }
+#endif
+
     return 0;
 }
 #endif
diff --git a/boot/zephyr/Kconfig b/boot/zephyr/Kconfig
index b2321103..1493dc31 100644
--- a/boot/zephyr/Kconfig
+++ b/boot/zephyr/Kconfig
@@ -522,6 +522,15 @@ config UPDATEABLE_IMAGE_NUMBER
 	help
 	  Enables support of multi image update.
 
+config BOOT_VERSION_CMP_USE_BUILD_NUMBER
+	bool "Use build number while comparing image version"
+	depends on (UPDATEABLE_IMAGE_NUMBER > 1) || BOOT_DIRECT_XIP || \
+		   BOOT_RAM_LOAD || MCUBOOT_DOWNGRADE_PREVENTION
+	help
+	  By default, the image version comparison relies only on version major,
+	  minor and revision. Enable this option to take into account the build
+	  number as well.
+
 choice BOOT_DOWNGRADE_PREVENTION_CHOICE
 	prompt "Downgrade prevention"
 	optional
diff --git a/boot/zephyr/include/mcuboot_config/mcuboot_config.h b/boot/zephyr/include/mcuboot_config/mcuboot_config.h
index a235e15a..e14bf4c0 100644
--- a/boot/zephyr/include/mcuboot_config/mcuboot_config.h
+++ b/boot/zephyr/include/mcuboot_config/mcuboot_config.h
@@ -93,6 +93,10 @@
 #define MCUBOOT_IMAGE_NUMBER    1
 #endif
 
+#ifdef CONFIG_BOOT_VERSION_CMP_USE_BUILD_NUMBER
+#define MCUBOOT_VERSION_CMP_USE_BUILD_NUMBER
+#endif
+
 #ifdef CONFIG_BOOT_SWAP_SAVE_ENCTLV
 #define MCUBOOT_SWAP_SAVE_ENCTLV 1
 #endif