armored: harden image integrity check against fault injections

[danielinux]

zd22067

[Copilot]

Pull request overview

This PR strengthens wolfBoot’s image integrity verification against fault-injection attacks by adding redundant digest comparison logic and additional hardened sanity checks to ensure integrity is confirmed before signature verification proceeds.

Changes:

• Replace the single digest compare in wolfBoot_verify_integrity() with a hardened comparison macro and a hardened success condition.
• Add new ARMORED integrity state redundancy (not_sha_ok, canary_FEEDCAFE) plus helper setters/clearers in struct wolfBoot_image.
• Add SHA_SANITY_CHECK() in wolfBoot_verify_authenticity() to assert integrity in a fault-hardened way before signature verification.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/image.c	Switch integrity verification to a redundant/hardened comparison flow and add an integrity sanity check before authenticity verification continues.
include/image.h	Extend ARMORED integrity state with redundant flags/canaries and add hardened macros for integrity verification and integrity sanity checking.

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