dropbear - compression is broken

[e9hack]

Am 26.02.2024 um 20:06 schrieb e9hack:
> in the past, it was possible to enable compression in WinSCP. Currently WinSCP reports an error when the copy operation starts:
> 
> Copying file 'D:\Download\carambola\openwrt-ath79-generic-tplink_archer-c7-v2-2-squashfs-sysupgrade-d240224.bin' fatally failed.
> Copying files to remote side failed.
> 
> Logread shows the following message:
> 
> Sat Feb 24 05:02:01 2024 authpriv.info dropbear[5311]: Exit (root) from <192.168.103.2:47725>: Bad packet size 34091

The issue is triggered by calling dropbear with parameter -W xxxx. If xxxx is larger than 32768, coping of large files does fail.

If option RecvWindowSize is not set in the dropbear configuration, a default window size of 262144 is used, which triggers the issue.

Regards,
Hartmut