1.4. Network API

The Network API provides utility functions to deal with IP addresses and send HTTP requests.

Functions

function httpGet(string url, string username = nil, string password = nil, int timeout = nil, bool return_content = false, bool cookie_auth = false)

Performs an HTTP GET request to the specified URL.

Parameters:

  • url – the URL to fetch.

  • username – for HTTP authentication.

  • password – the password for HTTP authentication.

  • timeout – maximum connection timeout in seconds.

  • return_content – enable sending response content back to the caller.

  • cookie_auth – Use basic (default) or cookie (used by ntopng) authentication

Returns:

table (RESPONSE_CODE, CONTENT_TYPE, EFFECTIVE_URL), with additional CONTENT and CONTENT_LEN if return_content is enabled on success, nil otherwise.

function httpPost(string url, string data, string username = nil, string password = nil, int timeout = nil, bool return_content = false, bool cookie_auth = false)

Send an HTTP POST request with url encoded data.

Parameters:

  • url – the target URL.

  • data – the url encoded data to send.

  • username – for HTTP authentication.

  • password – for HTTP authentication.

  • timeout – maximum connection timeout in seconds.

  • return_content – enable sending response content back to the caller.

  • cookie_auth – Use basic (default) or cookie (used by ntopng) authentication

Returns:

table (RESPONSE_CODE, CONTENT_TYPE, EFFECTIVE_URL), with additional CONTENT and CONTENT_LEN if return_content is enabled on success, nil otherwise.

function postHTTPJsonData(string username, string password, string url, string json)

Send an HTTP POST request with json content.

Note

HTTP header “Content-Type: application/json” is sent.

Parameters:

  • username – for HTTP authentication. Pass empty string to disable authentication.

  • password – for HTTP authentication. Pass empty string to disable authentication.

  • url – the target URL.

  • json – the data to post.

Returns:

true on success, false otherwise.

function send_udp_data(string host, int port, string data)

Send raw UDP data to a given host and port.

Parameters:

  • host – the host IP address.

  • port – the host port.

  • data – the data to send.

function inet_ntoa(int numeric_ip)

This is the equivalent C inet_ntoa for Lua.

Parameters:

numeric_ip – the numeric IP address to convert.

Returns:

the symbolic IP address.

function networkPrefix(string address, int netmask)

Apply a netmask to the specified IP address.

Parameters:

  • address – the IP address.

  • netmask – the network mask to apply.

Returns:

the masked IP address.

function httpRedirect(string url)

Send an HTTP redirection header to the specified URL.

Note

this must be called before sending any other HTTP data.

Parameters:

url – the URL to redirect to.

function httpPurifyParam(string str)

Purify a string from the HTTP standpoint. Used to purify HTTP params.

Note

The ourigied inout string with _ that replaced chars not allowed

Parameters:

str – the string to purify

function getservbyport(int port, string proto)

A wrapper for C getservbyport.

Parameters:

  • port – service port.

  • proto – service protocol, e.g. “tcp”.

Returns:

getservbyport result on success, the port value on failure.

function pingHost(string host, bool is_v6)

Send an ICMP request to the given host.

Note

this can be called multiple times on different hosts and then ntop.collectPingResults() can be used to collect the results.

Parameters:

  • host – the host name/IP address.

  • is_v6 – true for IPv6 connections, false for IPv4.

function collectPingResults()

Collect the ICMP replies after ntop.pingHost() calles.

Returns:

a table with IP address -> RTT mappings

function sendMail(string from, string to, string msg, string smtp_server, string username = nil, string password = nil)

Send an email to the specified address.

Parameters:

  • from – sender email and name

  • to – recipient email and name

  • msg – the message to send

  • smtp_server – the SMTP server address (e.g. smtp://myserver.com)

  • username – an optional username for the SMTP authentication

  • password – an optional password for the SMTP authentication

Returns:

true on success, false otherwise

function resolveHost(string ip)

Resolve the given IP into an host name.

Note

this call is blocking. Use getResolvedAddress() for a non blocking approach.

Parameters:

ip – the host IP

Returns:

the resolved host on success, nil otherwise.

function snmpget(string agent_host, string community, string oid, int timeout = 5, int version = 1, string oids)

Perform an SNMP GET request.

Parameters:

  • agent_host – the target SNMP host

  • community – the SNMP community

  • oid – the OID to query

  • timeout – maximum seconds before aborting the request

  • version – the SNMP version to use

  • oids – additional OIDs to query

Returns:

a table with the results on success, nil otherwise

function snmpgetnext(string agent_host, string community, string oid, int timeout = 5, int version = 1, string oids)

Perform an SNMP GETNEXT request.

Parameters:

  • agent_host – the target SNMP host

  • community – the SNMP community

  • oid – the OID to query

  • timeout – maximum seconds before aborting the request

  • version – the SNMP version to use

  • oids – additional OIDs to query

Returns:

a table with the results on success, nil otherwise

function tcpProbe(string server_ip, int server_port = 5, int timeout = 3)

Send a TCP probe and get the returned banner string.

Parameters:

  • server_ip – the server IP address

  • server_port – the TCP service port

  • timeout – maximum timeout for the operation

Returns:

the banner string on success, nil otherwise.

function isIPv6(string addr)

Check if the given address is an IPv6 address.

Parameters:

addr – the IP address to check

Returns:

true if the addtess is a valid IPv6 address, false otherwise.