Added the code with implementation of AES in CBC mode

[Northstrix]

AES_in_CBC_mode_for_microcontrollers-master.zip contains the code that enables the developer to easily integrate the AES-128, AES-192, and AES-256 in CBC mode to the RTL8720DN project.

By completing this PR sufficiently, please help us to review and improve the quality of this PR and Release Notes

Checklist

1. Please provide specific title that describe the change (eg. Update Readme.md)
2. Please provide related links (eg. This Pull Request is a fix of #issue_number)
3. Please update the license/declaration if applicable (eg. Usage of other projects/apis/libs code)
4. Please check Contributing guide
5. Please confirm option to "Allow edits and access to secrets by maintainers" when opening a Pull Request

This entire section above can be deleted if all items are checked.

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Description of Change

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• Feature:
• API Updates:
• Misc:

Tests and Environments

Please describe on what Hardware, SDK, IDE, OS that tested this Pull Request and how if necessary.
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• AMB21
• ambd_arduino V3.1.7
• Arduino IDE 2.3.0
• Windows 10

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• Closes #issue_number

[designer2k2]

There is a huge image in this zip, 14.208 x 3124 pixels, with 2,37MB. Is this really needed?

For example, just running the file over https://tinypng.com/ reduces it down to 0,3MB.

Also are you shure this is a valid arduino library?

[Northstrix]

There is a huge image in this zip, 14.208 x 3124 pixels, with 2,37MB. Is this really needed?

For example, just running the file over https://tinypng.com/ reduces it down to 0,3MB.

I updated the pull request and compressed the image.
Yes, Image is needed, it demonstrates how the algorithm works. The reason why I put it there in the first place is that CBC mode can be implemented with or without the IV encryption. The IV is encrypted in this particular implementation. Additionally I added the key incrementation after each block.

Also are you shure this is a valid arduino library?

Yes, I'm sure. I've used this library in several of my projects. In the archive that I included to the pull request, I put the library and the code that enables the developer to utilize that library to encrypt and decrypt data in AES in CBC mode.

[M-ichae-l]

Many thanks for the contribution.