Ignored loopback ip in ip probing

README.md

@@ -1,5 +1,135 @@
-# ftpserver2
+# Go FTP Secure server with support for local file system and Microsft Azure Blob storage
 
 [![Build Status](https://drone.io/github.com/MindFlavor/ftpserver2/status.png)](https://drone.io/github.com/MindFlavor/ftpserver2/latest)
 
 [![Coverage Status](https://coveralls.io/repos/MindFlavor/ftpserver2/badge.svg?branch=master&service=github)](https://coveralls.io/github/MindFlavor/ftpserver2?branch=master)
+
+### A pure go FTP Secure server with support for local file system and [Microsoft Azure Blob storage](https://azure.microsoft.com/en-us/documentation/services/storage/).
+
+
+
+The interface based file system makes easy to support different file systems. Please tell me if you are interested in something not covered here.
+
+## Features
+This server implements most - not all - the FTP commands available. This should be enough for most *passive* clients, below you will find a tested program list.
+
+The main features are:
+* Local file system support (ie standard FTP)
+* Azure blob storage backed file system
+* Unsecure (plain) FTP
+* FTP Secure explicit
+* FTP Secure implicit
+* File system agnostic
+* Pluggable logging system (thanks to [logrus](https://github.com/Sirupsen/logrus))
+
+### Implemented commands
+
+*	USER
+*	PASS
+*	PWD
+*	TYPE
+*	PASV
+*	EPSV
+*	LIST
+*	SYST
+*	CWD
+*	CDUP
+*	SIZE
+*	RETR
+*	STOR
+*	DELE
+*	FEAT
+*	QUIT
+*	NOOP
+*	MKD
+*	RMD
+*	REST
+*	AUTH
+*	PROT
+
+This list may not be updated: please refer to [session.go](ftp/session/session.go) source file to the updated list.
+
+
+## How to use
+The main FTP server object can be called on its own in your project. Here, however, I give you a very simple program to test it. In order to use it download it, compile it and launch it (here we assume you have a folder called ```ftphome``` in your ```C:\``` disk):
+
+```
+go get -u github.com/mindflavor/ftpserver2
+go install github.com/mindflavor/ftpserver2
+
+%GOPATH%\bin\ftpserver2 -lfs C:\ftphome
+```
+If you are in linux replace the last line with
+
+```
+sudo $GOPATH%/bin/ftpserver2 -lfs /mnt/ftphome
+```
+
+You need to be *su* in order to listen on port 21 (standard FTP command port). If you use another port you can start the program without *sudo*. Check the parameters section for how to do it.
+
+### Azure blob storage
+In order to have the FTP server serve the azure storage blobs simply replace the ```-lfs``` parameter with ```-ak``` and ```-an``` like this:
+
+```
+$GOPATH%/bin/ftpserver2 -ak <mystorageaccount> -as <shared_key_primary_or_secondary>
+```
+
+## Some screenshots
+
+This is an example of execution in ubuntu:
+
+![](http://i.imgur.com/NDupZcK.jpg)
+
+As you can see here, TLS is available (it's up to you to use valid certs however):
+
+![](http://i.imgur.com/Iv7d85S.jpg)
+
+Here is how an Azure storage account appears in Chrome:
+
+![](http://i.imgur.com/2cWdtM1.jpg)
+
+## Parameters
+At any time you can call the executable with ```-help``` flag in order to be reminded of the parameters.
+
+|Flag|Type|Description|Default|
+|---|---|---|---|
+|```an```| string |        Azure blob storage account name (*¢*)|```nil```|
+|```ak```|string|Azure blob storage account key (either primary or secondary) (*¢*)|```nil```|
+|```crt```| string|        TLS certificate file (*¢¢*)|```nil```|
+|```key```| string|        TLS certificate key file (*¢¢*)|```nil```|
+|```lDebug```| string|        Debug level log file|```nil```|
+|```lError```| string|        Error level log file|```nil```|
+|```lInfo```| string|        Info level log file|```nil```|
+|```lWarn```| string|        Warn level log file|```nil```|
+|```lfs```| string|        Local file system root (*¢¢¢*)|```nil```|
+|```ll```| string|        Minimum log level. Available values are ```Debug```, ```Info```, ```Warn```, ```Error``` |```Info```
+|```maxPasvPort```| int|        Higher passive port range |50100
+|```minPasvPort```| int|        Lower passive port range |50000
+|```plainPort```| int|        Plain FTP port (unencrypted). If you specify a TLS certificate and key encryption you can pass -1 to start a SFTP implicit server only |21
+|```tlsPort```| int|        Encrypted FTP port. If you do not specify a TLS certificate this port is ignored. If you specify -1 the implicit SFTP is disabled |990
+
+#### Notes
+
+(*¢*) These two flags must be specified together. If you need to retrieve the storage account key look here [http://stackoverflow.com/questions/6985921/where-can-i-find-my-azure-account-name-and-account-key](http://stackoverflow.com/questions/6985921/where-can-i-find-my-azure-account-name-and-account-key). You cannot both specify this flags and the local file system one (```lfs```).
+(*¢¢*) These two flags must be specified together. Without either one the secure extensions of FTP will be disabled. This article ([http://stackoverflow.com/questions/12871565/how-to-create-pem-files-for-https-web-server](http://stackoverflow.com/questions/12871565/how-to-create-pem-files-for-https-web-server)) explains how to generate both the certificate file and the key one.
+(*¢¢¢*) You cannot both specify this flag and the azure storage ones (```an``` and ```ak```).
+
+
+## ToDo
+
+* Better tests. Coverage is abysmal. Script unit testing for a distributed state machine such as FTP is a PITA though.
+* File access privilege check (right now is ignored).
+* Authentication. Right now the FTPServer delegates authentication to the caller but the provided executable does not validate the passed identity.
+
+## Tested clients  
+
+#### PC
+* [FileZilla](https://filezilla-project.org/).
+* [Chome](https://www.google.com/chrome/browser/desktop/).
+* [Firefox](https://www.mozilla.org/en-US/firefox/new/#).
+* [Internet Explorer](http://windows.microsoft.com/en-us/internet-explorer/download-ie).
+
+#### Android
+* [ES File Explorer File Manager](https://play.google.com/store/apps/details?id=com.estrongs.android.pop)
+* [Turbo FTP client & SFTP client](https://play.google.com/store/apps/details?id=turbo.client)
+* [FTP Client](https://play.google.com/store/apps/details?id=my.mobi.android.apps4u.ftpclient)

ftp/session/session.go

@@ -256,10 +256,16 @@ func getLocalIP() (net.IP, error) {
 			switch v := addr.(type) {
 			case *net.IPNet:
 				if v4 := v.IP.To4(); v4 != nil {
+					if v4.IsLoopback() {
+						continue
+					}
 					return v4, nil
 				}
 			case *net.IPAddr:
 				if v4 := v.IP.To4(); v4 != nil {
+					if v4.IsLoopback() {
+						continue
+					}
 					return v4, nil
 				}
 			}

main.go

@@ -21,7 +21,7 @@ import (
 	"github.com/rifflock/lfshook"
 )
 
-// example go install github.com/mindflavor/ftpserver2 && ftpserver2 -lfs C:\temp -ll Debug -lDebug D:\temp\ftp.log -lInfo D:\temp\ftp.log -lWarn D:\temp\ftp.log -lError D:\temp\ftp.log
+// example go install github.com/mindflavor/ftpserver2 && %GOPATH%\bin\ftpserver2 -lfs C:\temp -ll Debug -lDebug D:\temp\ftp.log -lInfo D:\temp\ftp.log -lWarn D:\temp\ftp.log -lError D:\temp\ftp.log -crt C:\temp\cert.pem -key C:\temp\key.pem
 
 func main() {
 	authFunc := func(username, password string) bool {