open https://gitlab.synchro.net/main/sbbs/-/issues/699

I'm going to paste in the text from a message I posted on DoveNet regarding this:

I've been off-and-on fighting with using 'setcap' to allow binding to ±
low ports as a non-root user, and today found (I think) what might be ±
causing my difficulties. ±
±
I've been doing my updates with an automated script, and the setcap °
option on the make line didn't seem to work. So, I was trying to use it °
in the update script as a command (sudo setcap ...<blah>). That didn't °
work either, and I think it's because there are weird/complicated things °
with 'setuid' and 'inherited' permissions type things in a bash script. °
With both of those issues not working, I just manually did the setcap °
command after the build was complete, and that works as expected. °
°
So today I once again used the command on the make line, thus: °
°
cd /sbbs/repo/src/sbbs3; make RELEASE=1 setcap install °
°
That *appears* to work, as the relevant make output is this:
°
Linking gcc.linux.x64.exe.release/umonitor °
make[1]: Leaving directory '/sbbs/repo/src/sbbs3/umonitor' °
sudo `whereis -b setcap | cut -d" " -f2` 'cap_net_bind_service=+ep' °
gcc.linux.x64.exe.release/sbbs °
install gcc.linux.x64.exe.release/* /sbbs/exec ±
install gcc.linux.x64.lib.release/* /sbbs/exec ±
install */gcc.linux.x64.exe.release/* /sbbs/exec ±
±
(side note: it doesn't prompt me for user password because I have my °
user allowed to run all sudo commands without a password). °
°
The problem is that it.... still doesn't work, 'sbbs' fails to bind to a °
low port number. So I started looking closer. In a Linux terminal °
window, my files appear in different colors depending on file °
extensions, when using the 'ls' command. The executable files in °
/sbbs/exec are green, for example. The 'sbbs' executable is green after running the build. If I manually use setcap to give it binding °
capabilities, it now shows as black text on a red background, which I'm °
sure means it is now considered some kind of "special" file. °
However.... the 'sbbs' executable in °
/sbbs/repo/src/sbbs3/gcc.linux.x64.exe.release/ is.... RED, even when °
the 'sbbs' executable in /sbbs/exec is green (not capable). What's °
happening is that the install commands there above that copy the newly °
compiled executables to /sbbs/exec remove the special capabilities. °
°
This problem isn't noticed by those that use 'symlinks' on their make ±
line, only when a person uses 'install', because that copies the file ±
somewhere else, which apparently breaks the capabilites that it's been ±
given.
--- SBBSecho 3.20-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)