Using encrypted 7z archives (Ubuntu, zip, 7zip)

7z.md

Using 7zip to create encrypted archives

Let's use 7zip for strong AES256 encrypted archives with a password. The guide assumes you're on Ubuntu 22 or newer. Note: this creates .7z archives, which is not the same as the regular .zip!

# Install 7zip. Note: don't install "p7zip-full" or "p7zip" (it's an older version!)
# Source, version things: https://askubuntu.com/questions/1465853/difference-between-several-command-line-tools-provided-for-7-zip-compression-li
sudo apt update
sudo apt install 7zip

# --> Version used here
7z --help

7-Zip 23.01 (x64) : Copyright (c) 1999-2023 Igor Pavlov : 2023-06-20
64-bit locale=en_US.UTF-8 Threads:18 OPEN_MAX:1024

# --> Create encrypted archive with sensible defaults (-p makes it ask for a password)
# The command works recursively on subfolders, too.
7z a \
  -t7z -m0=lzma2 -mx=9 -mfb=64 \
  -md=32m -ms=on -mhe=on -p \
   archive_name.7z ./my_folder

# --> Extract the archive to a non-existing output folder my_output (created when this is run)
7z x archive_name.7z -o./my_output

---

Bonus, view technical specs of archive:

# Command to check specs
7z l -slt archive_name.7z                                                                                                 Py sleepy


7-Zip 23.01 (x64) : Copyright (c) 1999-2023 Igor Pavlov : 2023-06-20
 64-bit locale=en_US.UTF-8 Threads:18 OPEN_MAX:1024

Scanning the drive for archives:
1 file, 943200 bytes (922 KiB)

Listing archive: archive.7z

Enter password (will not be echoed):  # <- you need to enter password again, here

--
Path = archive_name.7z
Type = 7z
Physical Size = 94320
Headers Size = 832
Method = LZMA2:1536k 7zAES     # <- 7zAES means AES256 encryption
Solid = +
Blocks = 1