**uFTP - FTP Server configuration** uFTP server can be configured with the "uftpd.cfg" configuration file, the location of the file can be either on the same path of the binary application or under "/etc/uftpd.cfg". Here below a sample "uftpd.cfg" configuration file. #FTP CONFIGURATION SAMPLE "/etc/uftpd.cfg" ####################################################### # UFTP SERVER SETTINGS # ####################################################### #MAXIMUM ALLOWED CONNECTIONS ON THE SERVER MAXIMUM_ALLOWED_FTP_CONNECTION = 30 #TCP/IP PORT SETTINGS (DEFAULT 21) FTP_PORT = 21 #Allow only one server instance (true or false) SINGLE_INSTANCE = true #Run in background, daemon mode ok DAEMON_MODE = true # Folder where to save the logs, use the same format below, the folder must terminate with / LOG_FOLDER = /var/log/ # Maximum number of logs to keep, if 0 log functionality is disabled MAXIMUM_LOG_FILES = 0 # Idle timeout in seconds, client are disconnected for inactivity after the # specified amount of time in seconds, set to 0 to disable IDLE_MAX_TIMEOUT = 3600 #MAX CONNECTIONS PER IP #LIMIT THE MAXIMUM NUMBER OF CONNECTION FOR EACH IP ADDRESS # 0 TO DISABLE MAX_CONNECTION_NUMBER_PER_IP = 10 #MAX LOGIN TRY PER IP #THE IP ADDRESS WILL BE BLOCKED FOR 5 MINUTES AFTER WRONG LOGIN USERNAME AND PASSWORD #0 TO DISABLE MAX_CONNECTION_TRY_PER_IP = 10 #USE THE SERVER IP PARAMETER IF THE FTP SERVER IS UNDER NAT #SERVER IP SHOULD BE SET TO ROUTER IP IN THIS CASE #IF NOT IN USE LEAVE IT COMMENTED OR BLANK #USE , instad of . eg: 192,168,1,1 #SERVER_IP = 192,168,1,1 #TLS CERTIFICATE FILE PATH CERTIFICATE_PATH=/etc/uFTP/cert.pem PRIVATE_CERTIFICATE_PATH=/etc/uFTP/key.pem #Enable system authentication based on /etc/passwd #and /etc/shadow ENABLE_PAM_AUTH = false # Force usage of the TLS # If enabled, only TLS connections will be allowed FORCE_TLS = false # # Random port for passive FTP connections range # RANDOM_PORT_START = 10000 RANDOM_PORT_END = 50000 #USERS #START FROM USER 0 TO XXX USER_0 = username PASSWORD_0 = password HOME_0 = / GROUP_NAME_OWNER_0 = usergroup USER_NAME_OWNER_0 = user USER_1 = apache PASSWORD_1 = apachePassword HOME_1 = /var/www/html/ GROUP_NAME_OWNER_1 = www-data USER_NAME_OWNER_1 = www-data USER_2 = anotherUsername PASSWORD_2 = anotherPassowrd HOME_2 = / #blocked user that are not allowed to login BLOCK_USER_0 = user1 BLOCK_USER_1 = user2 BLOCK_USER_2 = user3 **Parameters explained.** MAXIMUM_ALLOWED_FTP_CONNECTION = 30 Define the number of maximum client allowed connections on the FTP server, to reduce server memory usage this number can be reduced. FTP_PORT = 21 FTP server TCP/IP port, 21 is the standard FTP service port. SINGLE_INSTANCE = true If the single instance check is enabled, only one server instance can be executed. DAEMON_MODE = true When the daemon mode is activated uFTP server runs as a service in background, this option can be deactivated to run the server from the console for debug purpose. IDLE_MAX_TIMEOUT = 3600 Ftp clients are automatically closed if there is no activity for more than the specified number of seconds, every FTP commands reset the counter inside uFTP. MAX_CONNECTION_NUMBER_PER_IP = 2 FTP resource can be limited for each IP address by setting a maximum number of connections limit per IP. MAX_CONNECTION_TRY_PER_IP = 3 To prevent brute force attacks IP address are banned from the server for 5 minutes after the specified number of wrong login attempts. CERTIFICATE_PATH=/etc/uFTP/cert.pem The path of the public certificate (needed only if TLS/SSL support is enabled). # Force usage of the TLS # If enabled, only TLS connections will be allowed FORCE_TLS = true To enforce security, you can set FORCE_TLS = true, clients will need to use SSL. ENABLE_PAM_AUTH = true Enables/Disables the standard /etc/passwd, /etc/shadow authentication. PRIVATE_CERTIFICATE_PATH=/etc/uFTP/key.pem The path of the private certificate (needed only if TLS/SSL support is enabled). RANDOM_PORT_START = 10000 RANDOM_PORT_END = 50000 The range of random port will be used for data exchange between data and server for pasv mode. #USE THE SERVER IP PARAMETER IF THE FTP SERVER IS UNDER NAT #SERVER IP SHOULD BE SET TO ROUTER IP IN THIS CASE #IF NOT IN USE LEAVE IT COMMENTED OR BLANK #USE , instad of . eg: 192,168,1,1 SERVER_IP = 192,168,1,1 You can set SERVER_IP if you are under NAT, uFTP will respond to PASV commands with the address in the parameter if set. USER_0 = username PASSWORD_0 = password HOME_0 = / GROUP_NAME_OWNER_0 = usergroup USER_NAME_OWNER_0 = user USER_1 = apache PASSWORD_1 = apachePassword HOME_1 = /var/www/html/ GROUP_NAME_OWNER_1 = www-data USER_NAME_OWNER_1 = www-data USER_2 = anotherUsername PASSWORD_2 = anotherPassowrd HOME_2 = / #blocked user that are not allowed to login BLOCK_USER_0 = user1 BLOCK_USER_1 = user2 BLOCK_USER_2 = user3 Ftp users can be configured by using the user list pattern, the ids suffix must be added to each user list parameter the pattern is from "_0" to "(N)" for instance USER_0, USER_1, USER_2 ... USER_(N). Mandatory user list parameters: **USER_**(N) is the FTP username parameter. **PASSWORD_**(N) is the FTP password parameter written in plain text. **HOME_**(N) is the user home path, every user can be limited inside a directory. Option parameters: **GROUP_NAME_OWNER_**(N) if set to match an existing user group in the OS, every new file created by the FTP client associated with the N username and password will be created with the group ownership of the parameter. **USER_NAME_OWNER_**(N) if specified an existing user in the OS, every new file created by the FTP client associated with the N username and password will be created with the user ownership of the parameter. If one of the 2 optional parameter GROUP_NAME_OWNER_(N), USER_NAME_OWNER_(N) are not specified, the default uFTP user and group ownership are used for new file creations, typically root:root. #blocked user that are not allowed to login BLOCK_USER_0 = user1 BLOCK_USER_1 = user2 BLOCK_USER_2 = user3 You can list in the format above the user you want to block the access, they will be rejected if they attempt to login.