Max path length for Onedrive + crypt

[bandwidth]

Hi,
I'm using Onedrive with the crypt backend, using standard encryption for filenames. I'm trying to understand path and filename length limitations:

1. What is the maximum path length I can use (before encryption), given https://rclone.org/onedrive/ states Onedrive supports maximum path lengths of 400 chars?

2. https://rclone.org/crypt/ states the maximum support filename length is 143 chars, before encryption. Where is the fundamental limit coming from? Local filesystems?

3. What is crypt's overhead for filename encryption?

Thanks a ton for writing and maintaining rclone. It's beautifully designed, written, and documented, and the rare piece of software that behaves exactly as expected, which made it super simple to get up and running in minutes!

[calisro (Rob)]

@bandwidth

What is the maximum path length I can use (before encryption), given https://rclone.org/onedrive/ states Onedrive supports maximum path lengths of 400 chars?

Invalid file names and file types in OneDrive and SharePoint

It says 400.

@bandwidth

https://rclone.org/crypt/ states the maximum support filename length is 143 chars, before encryption. Where is the fundamental limit coming from? Local filesystems?

That's coming as a general statement to be safe across mostly all providers and the OS. On one drive it would be higher given the limit is 400. But your OS likely has limits if you want to copy it back down.

@bandwidth

What is crypt's overhead for filename encryption?

https://rclone.org/crypt/#name-encryption

[ncw (Nick Craig-Wood)]

If you try this rclone will work out what length it supports

rclone info --check-control=false --check-length=true --check-normalization=false --check-streaming=false cryptremote:

Note that is an internal debug command and not documented!

[bandwidth]

@calisro

It says 400.

I mentioned this in my question. What I'm wanting to find out is what this means for before-encryption length.

@calisro

That's coming as a general statement to be safe across mostly all providers and
the OS. On one drive it would be higher given the limit is 400. But your OS
likely has limits if you want to copy it back down.

I think you may be confusing path length and filename length. See my question.

@calisro

https://rclone.org/crypt/#name-encryption

I did read that before posting, but it unfortunately doesn't answer my question.

[bandwidth]

@ncw

Note that is an internal debug command and not documented!

Super helpful, thank you!

For the curious, OneDrive via Webdav shows me a limit of 362. My " /personal/[YOUR-EMAIL]/Documents" part of the URL happens to be 38 characters (see https://rclone.org/webdav/), making the sum 400. I assume this is more than a coincidence.

[ncw (Nick Craig-Wood)]

That command will leave a load of files called aaaa....aaa behind you'll need to delete BTW!

[bandwidth]

Yes, I noticed. This helped confirm to me that the command determines the length empirically.

I noticed the command also creates the remote path (mkdir) if it didn't exist

[ncw (Nick Craig-Wood)]

Yes there are all sorts of dangerous things on that command... I should probably tidy it up a bit!