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Problem

Despite introduction of #1295, Electrons sometimes still end up corrupting their DCD data (mainly keys).

Solution

This PR introduces a bugfix for a scenario where a valid secondary sector (marked with SEAL_INVALID_V2) is treated as invalid if primary is lost, causing DCD erasure.

This PR also introduces a couple of footer validations and fixes an issue during v1 -> v2 format upgrade, where the footer is not getting properly initialized, as well as fixes EC public key extraction/write procedure.

Steps to Test

• unit tests

Example App

N/A

References

• [CH10214]
• [CH10075]
• [CH10192]
• v2 dcd format and tests #1295
• [Original #1295] v2 dcd format and tests #1330

Completeness

• User is totes amazing for contributing!
• Contributor has signed CLA (Info here)
• Problem and Solution clearly stated
• Run unit/integration/application tests on device
• Added documentation
• Added to CHANGELOG.md after merging (add links to docs and issues)