Is the firmware data now encrypted?

[GxdTxnz]

I tried to binwalk firmware I downloaded #9 from the link http://download.tplinkcloud.com/firmware/Tapo_C220v1_en_1.1.4_Build_231109_Rel.66857n_up_boot-signed_1700216548774.bin, but it didn't give any results.

┌──(root㉿kali)-[/home/gxdtxnz/Tapo]
└─# binwalk Tapo_C220v1_en_1.1.4_Build_231109_Rel.66857n_up_boot-signed_1700216548774.bin --run-as=root

DECIMAL       HEXADECIMAL     DESCRIPTION
--------------------------------------------------------------------------------

Then I checked the file through ent, and saw entropy readings close to 8, which means the file is encrypted.

┌──(root㉿kali)-[/home/gxdtxnz/Tapo]
└─# ent Tapo_C220v1_en_1.1.4_Build_231109_Rel.66857n_up_boot-signed_1700216548774.bin
Entropy = 7.999986 bits per byte.

Optimum compression would reduce the size
of this 11870292 byte file by 0 percent.

Chi square distribution for 11870292 samples is 230.89, and randomly
would exceed this value 85.85 percent of the times.

Arithmetic mean value of data bytes is 127.4709 (127.5 = random).
Monte Carlo value for Pi is 3.139363379 (error 0.07 percent).
Serial correlation coefficient is 0.000014 (totally uncorrelated = 0.0).

Does anyone have any information on this?

[GxdTxnz]

Results on the file that passes binwalk

┌──(root㉿kali)-[/home/gxdtxnz/Tapo]
└─# ent Tapo_C200v1_en_1.0.10_Build_200520_Rel.45325n_1594713621606.bin
Entropy = 7.613347 bits per byte.

Optimum compression would reduce the size
of this 8376416 byte file by 4 percent.

Chi square distribution for 8376416 samples is 24331013.46, and randomly
would exceed this value less than 0.01 percent of the times.

Arithmetic mean value of data bytes is 140.8094 (127.5 = random).
Monte Carlo value for Pi is 2.806927165 (error 10.65 percent).
Serial correlation coefficient is 0.245518 (totally uncorrelated = 0.0).

[DrmnSamoLiu]

Yes, new OTA firmwares are mostly encrypted now.

[JayFoxRox]

Yes. I have developed a decryptor (which works on some firmwares, as the format sometimes differs) but haven't found time to clean it up for a public release.

[GxdTxnz]

Any information about the encryption method (algorithm, etc.)? I would try to write it myself
@JayFoxRox

[GxdTxnz]

Or if you can share, I'd like to use it.

[blah99995]

https://watchfulip.github.io/28-12-24/tp-link_c210_v2.html