I am writing a desktop application which requires the user's email id to be validated.
Can someone please tell me the c#.net implementation of the http://php.net/manual/en/function.checkdnsrr.php'>checkdnsrr() function in php and if it doesn't exist, give me some pointers to write my own implementation of it? I've searched the web for hours to get the answer but couldn't find one.
Thanks in advance.
Edit(s):
Please note that this question is NOT a duplicate of How to check if an email address exists without sending an email?
There really is no bulletproof way of doing this which can be relied upon, even though it has existed for years within the FINGER protocol; which for privacy/security/spam sake is disabled on most systems.
So that leaves us with several standard methods to verify, none of which is perfect. The most common ones I have seen in .NET have been of these varieties:
Regular Expressions: A variety of patterns are available to see if the pattern matches what the RFC says is a legitimate address.
System.Net.Mail Usage of the MailAddress class to see if a designated input can be a valid address. This actually does a pretty good job; however, it will allow items through that we would not consider valid addresses, such as no top level domain.
private bool isValidEmail (string emailAddress) {
bool ReturnValue;
try {
MailAddress ma = new MailAddress(emailAddress);
ReturnValue = true;
}
catch (Exception) {
ReturnValue = false;
}
return ReturnValue;
}
But what you are looking for will take a little more it seems. What I am reading is that you want to verify the host exists, and check to see if it can accept mail. I know of know pretty way to do that, but you can use a command shell to run nslookup with a type of MX to see if you get an acceptable return. The following code sample is incomplete in this regard, you will have to create a parsing function and develop to your own standard.
protected static bool DnsLookup(string HostName) {
ProcessStartInfo ProcInfo = new ProcessStartInfo("cmd");
ProcInfo.UseShellExecute = false;
ProcInfo.RedirectStandardInput = true;
ProcInfo.RedirectStandardOutput = true;
ProcInfo.CreateNoWindow = true;
bool ReturnValue;
using (Process process__1 = Process.Start(ProcInfo)) {
StreamWriter sw = process__1.StandardInput;
StreamReader sr = process__1.StandardOutput;
sw.WriteLine("nslookup -type=mx " + HostName);
sw.Close();
string Result = sr.ReadToEnd();
// Parse the Result string to determine validity
// and set ReturnValue
}
return ReturnValue;
}
What I would do would probably be to use a combination of the above. Use the MailAddress class to see if the format is valid, and then try to do the nslookup to see if the domain exists and has a mail server.
One caveat to the MailAddress class is that it parse the addresses into the local and domain portions, and appears to have an internal trim on the local portion; it will allow a space immediately before the # symbol; I generally do a space-check prior to implementation.
Related
Thank you in advance for any and all help.
I have seen several post on Stack Overflow and other sites on the net (including Microsoft Docs), but none seeming to help resolve my issue.
I am working on a project that connects to a xml file on a remote file share from WinPE. I have used suggestions from another post on SO about using the XmlUriResolver class to "moderate" success.
The issue I am currently being faced with is either a "Access Denied" error (several attempts to modify the XmlUriResolver.Credentials class) or a complete failure without any reason for failure. I am assuming it is going to be another "Access Denied" error, but my try/catch (Exception e) isn't capturing the reason.
Below is a snippet and relevant part of the method I am trying to implement:
relativeSysData = relativeSysData.Replace(#"\", "/");
SysdataXml = $"file://{_globaldata.Server}/{_globaldata.Share}/{relativeSysData}";
XmlUrlResolver XmlResolver = new XmlUrlResolver();
XmlResolver.Credentials = new NetworkCredential(_UserName,
_Password);
XmlReaderSettings xmlSettings = new XmlReaderSettings();
xmlSettings.XmlResolver = XmlResolver;
LogWriter.WriteLogFile((int)LogWriter.EventID.Xml, (int)LogWriter.EventType.Info,
$"Connecting to (remote) System information store at: {SysdataXml}");
xDoc = XDocument.Load(XmlReader.Create(SysdataXml, xmlSettings));
if (xDoc == null)
{
LogWriter.WriteLogFile((int)LogWriter.EventID.XmlError, (int)LogWriter.EventType.Error,
$"Unable to connect to the (remote) data store located at: {SysdataXml}");
deploy = false;
capture = false;
return result;
}
This part of the method is specific to accessing the remote data. I have a try/catch statement encompassing all of the method.
If I have an open connection to the Network Share, the method will work flawlessly, but will cause the application this application starts to fail - due to an open connection already.
I have a possible alternative to work round this solution but will cost extra lines of code.
Any help in resolving this matter, without resorting to WNetAddConnection() will be gratefully received
Kind Regards
Richie
N.B. I am aware that this is an authentication issue.
After research into how the XmlUrlResolver class works, I think that it may be referencing/accessing API's that are not included within the WinPE API framework.
After testing, I have used the WNetAddConnection2() API to connect to the Server and authenticate before anything happens, ensuring that the local name of the NETRESOURCE structure is left null, and that DisplayType is set to Server.
public static int ConnectToServer()
{
int result = 0;
var _netresource = new NetResource()
{
scope = _ResourceScope.GlobalNetwork,
ResourceType = _ResourceType.Any,
DisplayType = _ResourceDisplayType.Server,
RemoteName = $#"\\{Program._globaldata.Server}"
};
string _username = $#"{Program._globaldata.Server}\RemoteDKBuild";
string _passsword = "Hic3nuasno6epyndtenars4yDifrts";
var _connectiontype = (int)_ConnectionType.Interactive | (int)_ConnectionType.Temporary;
LogWriter.WriteLogFile((int)LogWriter.EventID.NetMan, (int)LogWriter.EventType.Info,
$#"Attempting to connect to: \\{_netresource.RemoteName}");
result = WNetAddConnection2(_netresource, _passsword, _username, _connectiontype);
var res = Marshal.GetLastWin32Error();
if (result !=0)
{
LogWriter.WriteLogFile((int)LogWriter.EventID.NetMan, (int)LogWriter.EventType.Error,
$#"Failed to connect to: \\{_netresource.RemoteName}, Return Result: {result.ToString()}, Win32 Error Code: {res.ToString()}");
result = res;
}
else
{
LogWriter.WriteLogFile((int)LogWriter.EventID.NetMan, (int)LogWriter.EventType.Info,
$#"Connection to: \\{_netresource.RemoteName} has been successfull.");
}
return result;
}
[DllImport("mpr.dll", SetLastError = true)]
private static extern int WNetAddConnection2(NetResource netResource, string password, string username, int flags);
I've seen many ways in powershell to force a computer to do a client action from the configuration manager.
Where I do work, it is not possible because we can't invoke commands on distant computer because it is blocked and the senior IT do not want to unlock it.
I did find a library in c# that allow me to do some action in sccm :
AdminUI.SmsTraceListener.dll
AdminUI.WqlQueryEngine.dll
I can add/remove computer to a collections, make queries and get the data, but I didn't find the way to force a computer to make an action from the configuration manager.
Is there someone here that knows if it is possible and how?
Thanks.
Edit 1: While searching in the MSDN documentation, I did find the TriggerSchedule Method in Class SMS_Client but I don't find the way to use it correctly. I think it might be the way to go, but i'm still stuck on this.
It is possible to trigger an Machine Policy Update via TriggerSchedule like this
ManagementScope scope = new ManagementScope(#"\\.\root\ccm");
ManagementClass cls = new ManagementClass(scope.Path.Path, "SMS_Client", null);
ManagementBaseObject inParams = cls.GetMethodParameters("TriggerSchedule");
inParams["sScheduleID"] = "{00000000-0000-0000-0000-000000000021}";
ManagementBaseObject outMPParams = cls.InvokeMethod("TriggerSchedule", inParams, null);
You already found the other Parameters for the sScheduleID in the link you posted. This uses standard WMI. With WqlQueryEngine you would get access to some WMI wrappers that can basically do the same thing. I do not see many advantages however.
Using the scope like this
\\.\root\ccm
makes the whole thing only work locally which is what you want if I understood you correctly. Otherwise replacing the . With a hostname or IP would make it work remotely. Only thing I found a bit strange is that it needs administrative rights, which should in theory not be necessary for a policy update request.
if someone is having the issue that nothing is happening, it is because WMI required higher rights. To leave triggering the actions also by the user, I switched to use the CPApplet:
TriggerSccmActions("Request & Evaluate", true);
private static List<string> TriggerSccmActions(string stringActions, bool boolContains)
{
List<string> actionName = new List<string>();
try {
const string ProgID = "CPApplet.CPAppletMgr";
Type foo = Type.GetTypeFromProgID(ProgID);
dynamic COMobject = Activator.CreateInstance(foo);
var oClientActions = COMobject.GetClientActions;
foreach (var oClientAction in oClientActions)
{
if (oClientAction.Name.ToString().Contains(stringActions) && boolContains)
{
var result = oClientAction.PerformAction();
actionName.Add(oClientAction.Name.ToString());
}
else if (!(oClientAction.Name.ToString().Contains(stringActions)) && !(boolContains))
{
var result = oClientAction.PerformAction();
actionName.Add(oClientAction.Name.ToString());
}
}
} catch(Exception e)
{
actionName.Add("Error: " + e.Message.ToString());
}
return actionName;
}
For me, EvaluateMachinePolicy Method in Class SMS_Client class worked. Here is the code:
public static void RefreshMachinePolicy(string machineName)
{
ManagementScope scope = new ManagementScope(string.Format(#"\\{0}\root\ccm", machineName));
ManagementClass cls = new ManagementClass(scope.Path.Path, "SMS_Client", null);
ManagementBaseObject inParams = cls.GetMethodParameters("EvaluateMachinePolicy");
ManagementBaseObject outMPParams = cls.InvokeMethod("EvaluateMachinePolicy", inParams, null);
Console.WriteLine("Policy refreshed successfully by EvaluateMachinePolicy method");
}
Here is the MSDN link for method details. Please include below namespace at the top of your source code file:
using System.Management;
I have a sonicwall on a network of around 100 machines.
I have tried and tried to find a way of creating 2 combobox's that will contain both the IP addresses linked to the sonicwall, as well as the currently logged in user of the machine as well.
What i am trying to create is a employee monitoring software (like Interguard/ActivTrak/etc), but am unable at present to even get near to finding this information?
I've been researching A LOT of stuff (~25 pages of google, with not a single link not clicked), and have met no conclusion as to get this information.
I'm not exactly a great programmer, but I would LOVE to be able to get this sort of information into two combobox's/arrays/other suitable object/control.
If anyone knows a way of even creating an array of IP addresses, along with corresponding Logins, that would be of great help to this project!
(PLEASE NOTE: I know there is a Networking exchange site, but I have already looked! Also, since i'm designing a piece of software for this, I thought i'd ask it here!)
Thanks for any advice/suggestions much appreciated!
What you looking for is similar to a packet sniffer application like wireshark or ethereal. But if you want to design it yourself, I think your best solution is a collection/list to store the data that is binded to a datagrid.
If you're in an Active Directory domain, you could use the code from my S/O question. Instead of using the CheckConnectionAsync() method to check for connectivity, you could just re-write it to get the IP address using System.Net.Dns.
To retrieve the user, you can use WMI. For this, you need to make a reference to the System.Management namespace.
public Task<string> GetUserName(string ComputerName)
{
return Task.Run(() =>
{
ConnectionOptions conn = ConnectionOptions()
{
EnablePrivileges = true,
Username = // string in format of #"DomainName\UserName",
Password = password,
Authentication = AuthenticationLevel.PacketPrivacy,
Impersonation = ImpersonationLevel.Impersonate
};
ManagementScope scope = new ManagementScope(#"\\" + ComputerName + #"\root\cimv2", conn);
try
{
scope.Connect();
ObjectQuery user = new ObjectQuery("Select UserName From Win32_ComputerSystem");
ManagementObjectSearcher searcher = new ManagementObjectSearcher(scope, user);
ManagementObjectCollection collection = searcher.Get();
foreach (ManagementObject m in collection)
{
string username = m["UserName"].ToString().Trim();
if(!String.IsNullOrEmpty(username))
{
return username;
}
}
return null; // no current logged in user
}
catch (Exception) // error handling...
});
}
Then, just iterate through your collection of computers and retrieve the username like so:
private async Task RetrieveUsers()
{
Parallel.ForEach(Computers, c =>
{
string user = await GetUserName(c.Name); // or c.IP. both work.
});
}
Can anyone tell me how to get track information from the MusicBrainz database from an audio file (mp3, wav, wma, ogg, etc...) using audio fingerprinting. I'm using MusicBrainz Sharp library, but any other library is ok.
I've seen that you must use the libofa library, that you can't use MusicBrainz Sharp to get puid from the audio file, but I can't figure out how to use libofa with C#.
Please show some examples and code snippets to help me, because I can't find them anywhere.
Thanks in advance!
The thing is that you can probably use libofa to get a fingerprint of the audio file, but if the file has no PUID available, you will be stuck and will have to use something like genpuid to submit the audio fingerprint to AmpliFIND and wait about a day to get a PUID.
That being said, I tried something similar about two years ago, but kinda lost interest in the project when I failed to write the IDv3 tags, if I remember correctly. However, the source code is available on Bitbucket.
I basically wrapped libofa using a DllImport and also wrapped genpuid (ie. read the output XML) to be able to read the fingerprint and submit the file for fingerprinting if I did not get one from libofa. I also wrote some code that reads information from MusicBrainz using MusicBrainz Sharp.
Well, at least that was what I planned back then, I think. :) I hope this helps you to solve your problem and I'd love to see an update on this.
Edit: I just noticed that I created a bug report for myself, which basically says that I still needed an implementation for my decoder which is probably why I created this question in SO. So I guess I did not implement the genpuid fingerprinter just to be able to do the fingerprint/get the guid, because I did not get the libofa fingerprinter to work correctly.
I did the wrapped genpuid approach suggested above.
private string GetPUID(string fileName)
{
Process p;
ProcessStartInfo si;
string outRow;
string puidReturned;
string gendPuidPath = #"C:\Program Files\genpuid\genpuid.exe";
string gendPuidKey = "your key here";
System.Text.RegularExpressions.Regex puidRex = new System.Text.RegularExpressions.Regex( #"puid: (\S+)" ); // sample: puid: 3c62e009-ec93-1c0f-e078-8829e885df67
System.Text.RegularExpressions.Match m;
if (File.Exists(gendPuidPath))
{
try
{
si = new ProcessStartInfo(gendPuidPath, gendPuidKey + " \"" + fileName + "\"");
si.RedirectStandardOutput = true;
si.UseShellExecute = false;
p = new Process();
p.StartInfo = si;
p.Start();
puidReturned = "";
while ((outRow = p.StandardOutput.ReadLine()) != null)
{
m = puidRex.Match(outRow);
if (m.Success)
puidReturned = m.Groups[1].Value;
Debug.WriteLine(outRow);
}
p.WaitForExit();
p.Close();
return puidReturned;
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
Debug.WriteLine(ex.StackTrace);
throw new Exception("Unexpexted Error obtaining PUID for file: " + fileName, ex);
}
}
else
{
Debug.WriteLine("genpuid.exe not found");
return "";
}
}
I can't seem to find a solution to this issue. I'm trying to get my Compact Framework application on Windows Mobile 6 to have the ability to move a file on its local filesystem to another system.
Here's the solutions I'm aware of:
FTP - Problem with that is most of
the APIs are way to expensive to use.
HTTP PUT - As far as I have been able to find, I can't use anonymous PUT with IIS7, and that's the web server the system is running. (An extreme workaround for this would be to use a different web server to PUT the file, and have that other system transfer it to the IIS system).
Windows share - I would need authentication on the shares, and I haven't seen that a way to pass this authentication through windows mobile.
The last resort would be to require that the devices be cradled to transfer these files, but I'd really like to be able to have these files be transferred wirelessly.
FTP: define "too expensive". Do you mean performance or byte overhead or dollar cost? Here's a free one with source.
HTTP: IIS7 certainly supports hosting web services or custom IHttpHandlers. You could use either for a data upload pretty easily.
A Windows Share simply requires that you to P/Invoke the WNet APIs to map the share, but it's not terribly complex.
I ended up just passing information to a web server via a PHP script.
The options provided above just didn't work out for my situation.
Here's the gist of it. I've got some code in there with progress bars and various checks and handlers unrelated to simply sending a file, but I'm sure you can pick through it. I've removed my authentication code from both the C# and the PHP, but it shouldn't be too hard to roll your own, if necessary.
in C#:
/*
* Here's the short+sweet about how I'm doing this
* 1) Copy the file from mobile device to web server by querying PHP script with paramaters for each line
* 2) PHP script checks 1) If we got the whole data file 2) If this is a duplicate data file
* 3) If it is a duplicate, or we didn't get the whole thing, it goes away. The mobile
* device will hang on to it's data file in the first case (if it's duplicate it deletes it)
* to be tried again later
* 4) The server will then process the data files using a scheduled task/cron job at an appropriate time
*/
private void process_attempts()
{
Uri CheckUrl = new Uri("http://path/to/php/script?action=check");
WebRequest checkReq = WebRequest.Create(CheckUrl);
try
{
WebResponse CheckResp = checkReq.GetResponse();
CheckResp.Close();
}
catch
{
MessageBox.Show("Error! Connection not available. Please make sure you are online.");
this.Invoke(new Close(closeme));
}
StreamReader dataReader = File.OpenText(datafile);
String line = null;
line = dataReader.ReadLine();
while (line != null)
{
Uri Url = new Uri("http://path/to/php/script?action=process&line=" + line);
WebRequest WebReq = WebRequest.Create(Url);
try
{
WebResponse Resp = WebReq.GetResponse();
Resp.Close();
}
catch
{
MessageBox.Show("Error! Connection not available. Please make sure you are online.");
this.Invoke(new Close(closeme));
return;
}
try
{
process_bar.Invoke(new SetInt(SetBarValue), new object[] { processed });
}
catch { }
process_num.Invoke(new SetString(SetNumValue), new object[] { processed + "/" + attempts });
processed++;
line = dataReader.ReadLine();
}
dataReader.Close();
Uri Url2 = new Uri("http://path/to/php/script?action=finalize&lines=" + attempts);
Boolean finalized = false;
WebRequest WebReq2 = WebRequest.Create(Url2);
try
{
WebResponse Resp = WebReq2.GetResponse();
Resp.Close();
finalized = true;
}
catch
{
MessageBox.Show("Error! Connection not available. Please make sure you are online.");
this.Invoke(new Close(closeme));
finalized = false;
}
MessageBox.Show("Done!");
this.Invoke(new Close(closeme));
}
In PHP (thoroughly commented for your benefit!):
<?php
//Get the GET'd values from the C#
//The current line being processed
$line = $_GET['line'];
//Which action we are doing
$action = $_GET['action'];
//# of lines in the source file
$totalLines = $_GET['lines'];
//If we are processing the line, open the data file, and append this new line and a newline.
if($action == "process"){
$dataFile = "tempdata/SOME_KIND_OF_UNIQUE_FILENAME.dat";
//open the file
$fh = fopen($dataFile, 'a');
//Write the line, and a newline to the file
fwrite($fh, $line."\r\n");
//Close the file
fclose($fh);
//Exit the script
exit();
}
//If we are done processing the original file from the C# application, make sure the number of lines in the new file matches that in the
//file we are transferring. An expansion of this could be to compare some kind of hash function value of both files...
if($action == "finalize"){
$dataFile = "tempdata/SOME_KIND_OF_UNIQUE_FILENAME.dat";
//Count the number of lines in the new file
$lines = count(file($dataFile));
//If the new file and the old file have the same number of lines...
if($lines == $totalLines){
//File has the matching number of lines, good enough for me over TCP.
//We should move or rename this file.
}else{
//File does NOT have the same number of lines as the source file.
}
exit();
}
if($action == "check"){
//If a file with this unique file name already exists, delete it.
$dataFile = "tempdata/SOME_KIND_OF_UNIQUE_FILENAME.dat";
if(file_exists($dataFile)){
unlink($dataFile);
}
}
?>