I discovered OpenSIPS and all the possibilities a few days ago. I would just use it as a simple SIP proxy to get started. Proxy between my designated UAC and my UAS (asterisk, not natted). The goal is to use a proxy to prevent bot attacks on my UAS.
After installing OpenSIPS, I tried to configure my XLITE (natted) by simply adding the proxy URL in the configuration. It works, I register and I can see in my UAS peers my extensions with proxy IP. But when I make a call, I got a forbidden error. In debug mode, the log does not talk to me, I see a lot of information but nothing about this error.
I did not make any changes to the default configuration script. Is this behavior normal?
I also tried with VM on public IP as UAC (so not named), same thing.
Thank you for your help.
Olivier
Most likely, your SIP INVITE is hitting this block:
if (!is_myself("$rd")) {
send_reply("403", "Relay Forbidden");
exit;
}
What this means is that your OpenSIPS does not consider itself responsible for the domain (or IP) that your SIP UA has placed in the Request-URI and is trying to route towards. To fix this, just whitelist the Asterisk IP as a local (recognized) domain using the alias statement:
listen = udp:*:5060
alias = 1.1.1.1
Related
I'm trying to get my head around SNMP for a project I'm working on. After I failed miserably getting it to work in my company's network, I set up a simple 3-device network to test things on, consisting of two Windows 10 PCs and a manageable switch between them.
I installed the optional feature "SNMP" on both PCs, made sure the service is running correctly and configured both services to accept SNMP queries from each other. I made sure to open up UDP port 161 in both PCs firewalls. Then I got the Net-SNMP binaries in order to use SNMPGET and SNMPWALK. As an alternative, I set up the SNMP extension for PHP through xampp (since I want to use PHP in my project once I get SNMP to work). Finally, I installed wireshark to monitor what exactly is going on and this is what I found:
When I try SNMPGET or SNMPWALK either through cmd or as a PHP command, I always get a timeout message. Wireshark is showing the get-next-request leaving one PC and arriving correctly on the other, so the network connection itself is working fine. But the receiving PC never sends a response. As I said, I'm pretty new to SNMP and I'm at a loss as to why this is happening. As I understand it, the optional feature for Windows 10 comes with its own SNMP agent, correct? If so, what could cause it to simply ignore an incoming request from a valid source IP?
The funny thing is that this even happens when I try to send an SNMP query to 127.0.0.1. I have no idea what I'm doing wrong...
Thanks to the comment of Lex Li, I was able to finally figure out which step I made a mistake with:
When setting up the SNMP service, under the security tab, I had to add 'public' as an accepted community name (with READ-ONLY rights). I figured since 'public' is sort of the standard read-only community, it would be accepted by default, which apparently it is not.
Alternatively, I guess I could have added my own communtiy name, but I didn't try that since I only want to read some values through SNMP anyways and read-only access is all I need for that.
Thank you very much Lex Li, I'm off to continue my project now!
In my current setup I have two interfaces, one is my normal connection and the other for my VPN, which is the default interface.
My VPN isn't nearly as fast as my connection so for some heavier load I use my normal connection. The problem I am having is that I want to send files to Google Drive by using their api via CMD, but googleapis.com simply resolves to too many IP's to route them all. Currently I am solving this issue by connecting through a proxy so I only have to route that proxy to my normal interface.
What I would rather do is just set the interface of my normal connection to the CMD session like I do with the proxy. I have tried playing around with netsh but so far with no success.
Does anyone have an idea on how to solve this problem?
It isn;t that your VPN is your "Default Interface" it's that it has a Lower Route Metric for Traffic because whoever set it up made it so that all traffic routes t the VPN instead of only internal traffic.
If this is intentional, and you don;t want to change it then your only real option is to use a Proxy as you need to be able to sniff the packet headers to match the API URL, and it's it's HTTPS traffic, that is encrypted, and only passing through a proxy will be able to get around that.
I tried using Burp suite to simulate the above for a particular domain. I am a beginner on this and don't know how to set it up. I couldn't find a built-in option for this.
Also, if there is no option, will I need to forward the request to some random IP address so that the connection gets timed out?
Update
Actually I doubt if redirecting to some invalid IP will give a connection timeout. Or will it give a timeout? I just want to know what response will I get if the server is down.
There isn't a feature to simulate "server down" but you can redirect as you suggest. If you redirect to an unused IP address (perhaps 192.168.99.99) you will normally get a timeout.
You can configure this in Proxy > Options > Proxy Listeners > Edit > Request Handling
You can just edit the response code to be a server error. You can do this automatically using match and replace as well.
I'm trying to get some protocols work through my company's firewall. Until now I have been succesfull in masking either http or https data by setting a http proxy on localhost and one on a remote server I own. The communication is done via $_POSTed and received modified .bmp files that contain a header and the encripted serialised request array.
This works fine, but there are a few drawbacks that make me think I might have taken a wrong approach.
Firstly I do not use apache's mod-proxy. instead I just created a local subdomain (proxy.localhost) and use that in browser's proxy settings. the subdomain's index.php does all the work. This creates some problems. I cannot use http and https simultaneously or the server will complain of using either "http on a https enabled port" or "incoresc ssl response length".
The second problem is, well, other protocols. I could make use of some ftp, sftp, remote deskoptop, ssh, nust name another... I need it
there are 2 solutions I can think of: First is if I run a php script in CLI so that it listens on a predefined port and handles the requests differently, or some sort of ssh tunnel. Problem is I haven't had any success with freeSSHd and putty because of my ignorance.
Thanks in advance for any advice.
I used the free version of bitvise SSH Client and server and it seems to work just fine.
We are attempting to connect to a WebDAV server using net use over SSL. On some servers we're seeing an issue in which this connection only succeeds if we specify port 443 in the URL.
Does Map
net use * "https://example.com:443/folder"
net use * "\\example.com#SSL#443\folder"
and, bizarrely, so does this:
net use * "\\example.com#SSLasdf\folder"
Does Not Map
net use * "https://example.com/folder"
net use * "\\example.com#SSL\folder"
In the non-working cases we consistently receive the following error:
System error 67 has occured.
The network name cannot be found.
We have noticed some things that might be useful information:
We have a test server that's configured the same way as the prod server and it works as expected.
In the non-working cases, no incoming requests are ever seen at the prod server from the failing host.
All clients are based on the same image.
The problem does not manifest uniformly on all clients -- some work, some don't.
There is an existing, valid entry for example.com in the client DNS cache.
Flushing the client DNS cache of the affected servers does not resolve the problem.
Once the problem appears, it seems to stick. That is, if I execute one of the working mappings, delete it, and then immediately execute one of the non-working mappings, the problem persists.
We are utterly stumped. Any theories?
You are seeing different behaviors because you are connecting using different names. Once a name has been attempted and failed, the WebClient (this is the service that enables WebDAV) will cache the response for a period. To clear the cache, locate the WebClient service in the Services console and restart it. Or from an administrative command prompt execute the following command:
net.exe stop webclient && net.exe start webclient
We ultimately determined that we were mis-interpreting the System Error 67 that net use was returning. We discovered two interesting things:
In the event that the WebDAV returns a 404 or a 50x on the initial, root folder PROPFIND, net use will (rightly) interpret this as the root folder being unavailable. The fact that it says the network name could not be found let us to believe that the problem was with the name resolution, but it was really just saying, 'hey, I couldn't find anything at this path.'
If 'net use' fails due to a 404/50x, it appears that for a brief period of time it will automatically fail any additional mappings for that same host without issuing a request. For example, if net use http://me.com/foo returns a 404, then net use http://me.com/bar will instantly fail if made in rapid succession to that first call, and no request record will be seen in the WebDAV server logs.
My best guess is that appending the #443 port didn't make any real difference. What it perhaps did do was to trick net use into thinking it was talking to a different host, at least for the purposes of its 'auto-fail' feature. But that's just a guess.