Password prompt during --customize

[c-ftw]

First of all, excellent work on this. I was working on something similar myself - albeit far more rudimentary - when I stumbled on this while trying to work out how to add apps to an image file. I immediately ditched what I was working on. Using sdm has saved me many headaches. Anyway...

I've noticed that the password prompt in the user plugin only prompt for the password once. It really should ask twice and compare, which is pretty standard, so I re-wrote the getpassword function. Please feel free to add it to the next version.

function getpassword() {
    local pwd pwd2 pwuser="$1"

    while [ true ]
    do
        while [ true ]
        do
            echo -n "Password for $pwuser: " && read -u 0 -s pwd
            echo ""
            [ "$pwd" != "" ] && break
        done

        while [ true ]
        do
            echo -n "Retype Password for $pwuser: " && read -u 0 -s pwd2
            echo ""
            [ "$pwd2" != "" ] && break
        done
        [ "$pwd" = "$pwd2" ] && break || echo "Passwords do not match. Try again."
    done

    # userpwd must be defined in scope above this so it can be used
    # had problems calling this as a function
    printf -v userpwd "%s" "$pwd"
}

[gitbls]

Thanks. I'll add this to the TODO list.

[c-ftw]

I found a cheeky way around this. I added "stty -echo" to the start of sdm. Then made sure it ran "stty echo" before entering/exploring the image and also in the exit trap. Now I can just type the password twice when the script starts, and the buffer will place the 2 lines in the appropriate variables when it gets around to executing the read. This achieved my purpose without compromising security.

[gitbls]

Mine is a bit slower than that. The machine running sdm is a VM on an SSD, the IMG files are not on the VM, they're on a samba share on the VM host, spinning rust. If I copied the IMG files to the VM, it'd run much faster, but that would mean copying several large files to the VM/SSD, which I'm not really keen on doing.

There's probably no point in compromising security to save most people a few second, so maybe best to leave it as it is. The entire point of prompting for a password is that it's not saved anywhere.

OK, you're definitely more patient than I am 🤣

[gitbls]

I found a cheeky way around this. I added "stty -echo" to the start of sdm. Then made sure it ran "stty echo" before entering/exploring the image and also in the exit trap. Now I can just type the password twice when the script starts, and the buffer will place the 2 lines in the appropriate variables when it gets around to executing the read. This achieved my purpose without compromising security.

Great that you found a solution! As soon as I saw this I realized that sdm can help you with this. I'll add a method for you to run a script at sdm startup and in the exit trap, eliminating the need for you to edit sdm whenever you update it. Haven't fleshed out the details, but I'm thinking that the script would be called with an argument indicating 'begin' or 'end' or similar.

Would that be helpful from your perspective?

[c-ftw]

Well... it didn't quite work as expected. I made it turn echo off (stty -echo) when the script started, but for some reason it came back on again almost immediately. I'm not sure why. Perhaps they guy who wrote it might know. :)

Yeah, I think that would probably be handy in general. However I think in this case, it would also need to run before exploring the IMG file at the end. I don't know what would happen if echo was turned off when that started.

[c-ftw]

OK, you're definitely more patient than I am

TBH, I'm a little concerned about the issue of moving large amounts of data around on SSDs. They say it's fixed, but I know first hand that's there's still an issue. I have an SSD in a USB enclosure that started playing up immediately after the windows update that caused the issue, and it works fine on Linux. As these VMs run on a windows host, I'm just playing it safe.

[gitbls]

Here's a possible solution for you. LMK your thoughts.

Do the customize and add < /dev/tty or < /path/to/file on the end.

As soon as sdm starts up, type the password twice (if /dev/tty) or have the password on 2 lines in /path/to/file.

Also use the --batch switch so that sdm exits after the customize has completed.