- `DHPARAM_FILE` is a local var not intended for overriding via ENV. Clarified that with `local` declaration.
- `FFDHE_GROUP` var uses default assignment (_`:=4096` instead of only substitute `:-4096`_), so that `DHPARAM_BITS` retains the default 4096 value in subsequent references if no custom size was provided.
- Refactored the conditional statements to only handle early failure conditions. Shifting out the RFC7919 support that can run after all checks have passed.
- Revised comments.
Implicit URL is unnecessary (_and presently relies on Github redirecting from it's original mapped URL_).
Use an explicit URL instead to reduce the guesswork/trust of where the shortener was going to redirect to.
- `==` for string equality since we're using bash `[[ test ]]` already.
- Uppercase `socket_file` variable to be consistent with other internal variables used in the script.
- Convert `[ test ]` to `[[ test ]]` for consistency, improving maintenance. Double-bracket (_not posix compatible_) does not require quoted variables, ShellCheck lint knows this is safe too :)
- `-z` test for `$RESOLVERS` is native syntax to check for empty string value.
- Referenced variables should generally be wrapped like so `"${VAR}"`.
- Variable assignments with string values should be double quotes for content with variables, otherwise use single quotes (_no interpolation_).
- Converted my if statements to use the same style used in the rest of the file.
- While the anonymous VOLUME can be dropped from Dockerfile, the path needs to be valid at run-time, might as well ensure it's available by creating the dhparam folder at build.
- Generation logic no longer necessary, dropped.
- Standardized RFC 7919 groups added (2048, 3072, 4096), with 4096-bit remaining the default size. The DH logic can live in the entrypoint script as well.
- Third-party supplied pre-generated DH params removed as they're not considered trustworthy compared to RFC 7919 groups.
