On 11 Jan 2025, Warpslide said the following...

I opted for proftpd as well and use its "virtual user" functionality.

[...]

I still need to find a way to create a semaphore file when someone logs out of proftd. There is an "ExecOnExit" but these are limited to the user's chrooted path.

In case someone else finds this useful, I asked ChatCPT to help me with a script to run some commands when specified users log out of the proftpd server. It seems to work well enough but hasn't been battle tested as of yet:


[-- begin monitor_ftp_log.sh --]
#!/bin/bash

# Path to the log file
LOG_FILE="/var/log/proftpd/proftpd.log"

# Declare an associative array to store user login info (PID -> User)
declare -A user_sessions

# List of specific users to monitor
MONITORED_USERS=("node23" "node99")

# Action to be performed when the session is closed
perform_action() {
local user="$1"
case "$user" in
"node23") inbox="/home/ubuntu/fido/filebox/micronet_z618n400n23p1/in" ;;
"node99") inbox="/home/ubuntu/fido/filebox/micronet_z618n400n99/in" ;;
esac
[ ! -z "$(ls "${inbox}")" ] && mv -n ${inbox}/*.* /home/ubuntu/fido/inbound && /home/ubuntu/fido/mailin.sh
}

# Function to check if a user is in the monitored list
is_monitored_user() {
local user="$1"
for monitored_user in "${MONITORED_USERS[@]}"; do
if [[ "$user" == "$monitored_user" ]]; then
return 0 # User is in the list
fi
done
return 1 # User is not in the list
}

# Monitor the log file
tail -F "$LOG_FILE" | while read -r line; do

# Check for successful login lines (USER <username>: Login successful)
if [[ "$line" =~ USER\ ([a-zA-Z0-9]+):\ Login\ successful\. ]]; then
user="${BASH_REMATCH[1]}" # Extract the username

# Extract PID from the first set of square brackets []
pid=$(echo "$line" | awk -F'[][]' '{print $2}')

# Only monitor specific users
if is_monitored_user "$user"; then
# Store the user and PID in the associative array
user_sessions["$pid"]="$user"
fi
fi

# Check for FTP session closed (FTP session closed with PID in the first set of [])
if [[ "$line" =~ \[([0-9]+)\].*FTP\ session\ closed\. ]]; then
pid="${BASH_REMATCH[1]}" # Extract the process ID (PID)

# Check if this PID exists in the user_sessions array
if [[ -n "${user_sessions[$pid]}" ]]; then
user="${user_sessions[$pid]}"

# Only perform action for monitored users
if is_monitored_user "$user"; then
perform_action "$user" # Perform action for the associated user
fi
unset user_sessions["$pid"] # Remove the entry after the action
fi
fi
done
[-- end monitor_ftp_log.sh --]


You can also find a copy at:
https://nrbbs.net/monitor_ftp_log.sh.txt


Jay

... What if soy milk is just regular milk introducing itself in spanish?

--- Mystic BBS v1.12 A49 2024/05/29 (Linux/64)
* Origin: Northern Realms (618:400/23)