What can be done to know and list all running processes on a remote computer?
One idea is to have a server listening to our request on the remote machine and the other one is to use ssh.
The problem is i dont know whether there will be such a server running on the remote machine and i cannot use ssh because it needs authentication.
Is there any other way out ?
If you
cannot install a server program on the remote machine
cannot use anything that requires authentication
then you should not be allowed to know the list of all running processes on a machine. That request would be a security nightmare!
You can do something much simpler without (as many) security problems: scan the publicly-available ports for programs that are running. Programs like nmap.org let you know a fair bit of information about the publicly-running programs on machines.
I have done something similar in the past using SNMP. I don't have the specifics in front of me, but something like "snmpwalk -v2 -c public hostname prTable" got me the process table. I recall later configuring SNMP to generate errors when the number of processes didn't meet our specified requirement, like httpd must have at least 1 and less than 50.
I suggest you look at the code for a remote login, rlogin. You could remotely login to an account that has the privileges that you need. Once logged in, you can fetch a list of processes.
This looks like a good application for a script rather than a C or C++ program.
Related
I have a problem with a web service that is installed and started with a .msi that is created with the WiX toolset.
The service can be installed and started on all the machines I tested so far (shown as running in the Services Manager) but on some machines it is not reachable (for example via a browser) and not shown in the list of listening ports on that machine (displayed with 'netstat -a').
I am trying to figure out what's going wrong but I am not really familiar with web service development and configuration. It's a third party service, thus I don't know how it works internally.
A good starting point for me would be to find out, what exactly happens when a service is installed and started during the execution of the .msi-file.
Maybe I could try to tackle the problem on a lower level then.
Below is my code in the ServiceInstall-Element:
<ServiceInstall
Id="ServiceID"
Type="ownProcess"
Vital="yes"
Name="ServiceName"
DisplayName="ServiceDisplayName"
Description="Lorem Ipsum"
Start="auto"
Account="LocalSystem"
ErrorControl="normal"
Interactive="no"
Arguments="action=run">
</ServiceInstall>
The argument is important - without it, the service won't start or run.
Maybe someone else encounterd the same or a similar problem and can help me out.
Thanks already in advance - each hint is appreciated.
EDIT I (15.04.18):
As it might be a problem with the specific service, I will add some further information here:
It's a third party software called CryptoLicensing:
http://www.ssware.com/cryptolicensing/cryptolicensing_net.htm
Part of this software is that specific program, that serves as a License Server and does the license registration, for example in a customer's network.
The service can be run as a Windows application or installed and run as a Windows service. In both cases it should be listening on a (pre-)specified port on the installed machine.
Whenever I start the .exe as an application, everything works as intended. The service is reachable (for example with the browser) and can be accessed from other machines in the network.
When the .exe is installed and started as a service, it does not work as intended on every machine. For example if I install and start the service on my laptop, it is shown as running in the Services Manager, but is not reachable on its assigned URL (not even on the localhost) nor is the specific port displayed in the active listening ports, for example with 'netstat -a'.
The service itself starts without any error messages and does not log any errors or exceptions as it seems to be running without any problems.
I contacted the vendor, but sometimes he doesn't reply quickly and he is not very specific in his replies.
Before asking the question I assumed that it was a problem with the Windows user rights and the WiX installer but during the discussion here I had the feeling that it might a problem with the service itself.
I hope this 'new' piece of information helps in isolating and location the problem.
Thanks to everyone who helped so far!
Hopefully not stating the obvious here, but WiX doesn't do much except populate the ServiceInstall table in the MSI file, so this is about why Windows Installer won't start the service. ServiceInstall table:
https://msdn.microsoft.com/en-us/library/windows/desktop/aa371637(v=vs.85).aspx
Also, this isn't really about ServiceInstall - it's probably about the ServiceControl element in your WiX source, but it's not clear whether that's how you're starting it or if you're starting it manually later on. That does make a difference. What is the error message and where are you getting it, and is it a 1920 or 1921 error (in the context of ServiceControl).
The main reason a service will start on one system but not another is missing dependencies. If your service is C++ based (the post doesn't say) then there are probably dependencies on C runtimes, UCRT runtimes, MFC or ATL runtimes and so on.
First: are you sure this service is intended to run as LocalSystem? (MSDN, SO).
Second: did you check the event logs in detail for anything obvious? If the service is good you should find a hint at least. Something to start with. I find that I sometimes miss the actual logs in the event viewer because it is so "crowded". My take on it: empty the log and stop and restart the service.
Something locking / blocking: If the service installs and runs OK I would suspect other factors such as firewalls (hardware & software), security software in general (anti-virus, malware scanners), network configuration issues (proxies, WINS, DNS and all the complexities involved in networking). Is the service trying to reach an UNC path?
Diverse Machines: What are the target machines? Are they virtual, are they physical, are they test machines, are they operative SOE machines in corporate networks? Are they the same OS version and edition?
Further Ideas: It is not quite related, but maybe skim this list of suggestions for debugging from another answer (I am not sure why it was down-voted, I think it is an OK list to inspire debugging ideas): Windows Application Startup Error Exception code: 0xe0434352 (maybe just skim the bolded words for ideas - Recommended).
sc.exe: And finally, perhaps check the sc.exe tool (Service Control) and see if it can provide you with some useful information for debugging.
sc.exe in the context of killing hung services (sample use).
sc.exe from MSDN
Some further links:
Windows Services Frequently Asked Questions (FAQ). Content seems to be up to date - at face value at least. These guys claim to be experts on services. I have no idea who they are.
Essential Tools for Windows Services: SC.EXE
Run Service Control (sc.exe) command on secure port
After almost 20 months we finally (and accidentally) found a solution to the problem! For the few machines, on which the service did not run properly, setting the NoInteractiveServices value in the registry to 0 did the trick. A value of 1 (which is default) means that no service is allowed to run interactively, regardless of whether it has the SERVICE_INTERACTIVE_PROCESS property. More information on Interactive Services.
I am not completely satisfied with the solution, because on all the other machines NoInteractiveServices is set to 1 AND the service runs properly anyway. However, on the machines where the service did not run interactively this solution worked for us. Thus I will accept this as an answer.
If anyone has more information on this issue and can explain why this works, feel free to
add them - I would be very interested!
I'm writing a cross-platform app that I would like to run on Linux-based operating systems like Fedora and Ubuntu. I use QSerialPort and it works fine. I can use QSerialPortInfo to get a list of serial ports in the system and present them to the user who can select which one s/he wants to use.
However, on Linux systems, by default the user doesn't have permissions to the serial ports. I know that it is wrong to run my app with sudo and I also know that it is not user friendly to ask the user to run chmod 666 on the serial port manually every time the app is used. So I looked around and it seems to me that polkit is the answer, however I haven't been able to find any example which would show me how to do it.
Can you please tell me how to use polkit (formerly known as policykit) to request permission for my app to use a specific serial port?
EDIT:
What I'm looking for is a way to:
Check if the user has access to the serial port
If not, pop up a dialog that asks for permission (like the Gnome settings app for example)
If the user authenticated successfully, make the serial port available to the app.
Some more thoughts
I do NOT want to set up an udev rule that gives perimission to every serial port
I do NOT want to ask the user to run a script
I do NOT want my app to run as the superuser
I do NOT want any other actions performed as root, just the serial port access
Yes I've found the official polkit docs, but they are not very clear on how to do this.
General thinking:
It is not a good idea to try to make an application "universal".
I understand that you want your software to be easy to use, but for things like this (system's settings), you should rely on the system packagers.
At anytime, polkit can be replaced by another solution, or ressource's name can be changed, or whatever and your application would be no more usable.
I advise you to:
at most, raise a polkit windows that woulde ask for password
or better, to make distribution packages that will do the necessary tweaks through regular scripts
An idea
I didn't do it (but I played a lot in the past with pam :-) )
So here are links that I found and what I understood:
polkit acts the same way as sudo do: it allow you to run program with another identity (explanations)
so you can run your program either as root or as one having enough right access to the serial
So you could create:
an install script that allow to run your program with the good identity (e.g. example). That way you would ask root password once (at the install for creating the polkit policy), and each time the user wanted to run your program. That identity maybe root or any identity as long as that identity has R/W access.
a policy file: you can look either at 1 or documentation
a script for lauching your program containing something like this: pkexec <path>/<pgm>
Here are some pointers:
an admin guide to polkit: 3
(I'm a debian user but I like their docs)
the official documentation: https://www.freedesktop.org/software/polkit/docs/master/index.html
I want to run Linux command remotely from Window based Qt C++ application programmatically. What is the simpliest way to do it?
You need some sort of server on the Linux machine and your Windows machine will be a client. I'd say the easiest way would be just make a php script to run your command and drop it in your www root and have your Windows machine fetch that URL.
At the end of the day, without knowing what your requirements are with regard to security and with regard to what kind of commands you'll be running is, it's very difficult to give a definitive answer to this question.
Simply connect to telnet server on the linux using sockets, and send the commands.
This actually requires very little code. Check the Java version here:
Sending telnet commands and reading the response with Java
You can do similarly with Qt/C++ as well.
Simple server-side program witch will handle the requests and then using ex system() function will be this "remotely" part of solution.
And on client-side simple text field handled by function witch will be able to connect to server to send command run request.
The most important thing in this solution will be to take care about security.
One way to do it is, to have a client-server model, the server resides in linux and client can be your computer. That way you can send commands to the server and have its output thrown at you. That's one way I think of this problem.
Use UPnP to get past the firewall(or use NAT traversal or UDP/TCP hole punching). Otherwise (without forwarding the port) it would be impossible to reach the server.
The second is to write your own RSH and SSH utility. (or use putty or other pre-existing software)
You could use Plink if you are on Windows whatever version. If you can run PuTTY, then you can run PLink. PuTTY Plink Documentation. Using that you could use the executable, and automate things. Otherwise, if you're looking for a specific programming language, they'd still be dependent upon some SSH Library. If you're writing your own installer, you could include the PLink.exe in your installer, and distribute it with your application.
From the documentation page:
Z:\sysosd>plink login.example.com 'echo "Hello World"'
Either this this question isn't asked often (possible), everyone knows how to do it (doubtful), or I don't know how to search for it (likely).
I want to get my C++ program talking to my MySQL server and able to run commands on it. I know MySQL has connector code available, but 1) it seems like much more than I need and 2) I just cannot seem to get it to work anyway.
I want to be able to test the program on my computer, so remote access would be necessary. I do have SSH for the server.
My final deployment will be able to run on the server itself.
Executing and receiving/parsing output from MySQL databases is quite easy to do by hand. I can't however, figure out which way to go to get my program to do this.
I figure I should be able to:
1. ssh into the web server (with password)
2. access the MySQL database
3. execute statements and retrieve their output
I've read a lot about fork() and popen(), but due to their read-only or write-only limitations (unless I misunderstand), I just don't know where to go. Obviously I'd just take out the SSH step when the time comes to deploy it on the server. Can somebody give me some direction on this, or is this just not possible (doubtful).
It is our own dedicated server so we have full reign with ssh and WHM, but I'd rather minimize the "intrusion" since I don't know enough about all the software on there if I broke something. I just want to communicate [directly] with the MySQL database.
Thanks so much! You guys are awesome!
If you have SSH access, then you're way overcomplicating this.
Step 1: Set up an SSH tunnel:
ssh -L 3306:localhost:3306 user#your.host.com
Step 2: Use the local port like normal (i.e. just refer to localhost)
mysql -u root -p < somescript.sql
However since you're using C++, you really should use a proper library (e.g. MySQL++). Educate yourself on SSH tunnels, they make life so much easier once you know about them.
I am a total newbie in servers/hosting etc, although I have some experience in programming in C,Java,etc. So excuse me if the question is 'absurd'.
I recently bought service from a hosting site,namely this(hostmds). I have some code I've written in C++ and I want to run it in the hosting site. So my question is:
Is this possible, or will I have to rewrite everything in a new language?
What should my approach be?
Edit: I have a Shared-Hosting account.
You will have to get a "virtual private server" account from your host in order to do this. This will enable you to compile your program on your host machine and run it essentially as if it were a separate machine under your control.
This means you will also be responsible for maintaining your own HTTP server program (such as Apache, if running on a Linux/Unix host), and your own database servers and other support.
If you have a "shared hosting" account (the most common low cost option) with SSH support, you may be able to compile your program, and even run it, but you will be subject to the whims (capricious or otherwise) of the administrators of your system (that it, you may find that libraries you need are removed or moved around)
What type of hosting is this?
What kind of application is this, is it a daemon?
Depending on the amount of access rights you have, you can run the code in the cgi-bin folder or through the shell of the server.
Depending on the OS/compiler you've used to write your code in you might have to modify some things so that it'll work on the target OS. You should probably add some more details. :)
Many hosting services provide CGI/FastCGI/SCGI that can be used for running C++ webapps. However, it depends on your host whether you can actually do this, as it may be difficult to get binaries built on some other system to run on the web hosting service (if you even can upload them in the first place).
On shell services and virtual servers you can also run daemons (that directly listen to a port), but especially on shell services you cannot listen on low ports (0..1024), for security reasons.
Notice that the cheapest hosting packages generally only allow PHP at most, so you will need something more expensive for more access.
It is best to ask the hosting provider for further information, as these things wildly differ from host to another.