I'm using Node.js and Express as backend to my app, and wish to upload a photo to facebook.
I came across this method of uploading an image by url: https://developers.facebook.com/blog/post/526/
Now all I need to figure out is what is my own base url, so I can assemble the full address of mt photo (say /photos/12345 should be http://www.mydomain.com/photos/12345)
Is there any way to do so? some Node env variable perhaps?
Thank
Basically, you bind Node.js / Express to a port, and perhaps to an IP address. So your question comes down to:
Is it possible to find out just by an IP address which domain name it is used by?
And the answer to that is simply: No, unfortunately not.
Reason: You can bind several domain names to the same IP address. So all you could do is query the DNS server of your choice for a reverse-lookup of the IP address to get a list of domain names. If you are lucky, there is only one. If not, there are more.
And, as an additional problem: If your code does not explicitly bind itself to a specific IP address you do not even know which IP address to use - there will be more than one: At least a IPv4 one, loopback, probably IPv6, ... potentially more if there is more than one network card, ...
So, bottom line: If you have a lot of good luck, yes, but there is no reliable method that works under every circumstance.
Related
I noticed that one of Google's mail servers (alt4.aspmx.l.google.com) points to 74.125.200.26, but when I do a reverse DNS lookup on that IP I see that the hostname associated with it is sa-in-f26.1e100.net. My limited understanding of DNS is that when you have a situation like that, one hostname is an alias of the other, but that's not the case here.
My initial goal was making a Python program that given an IP address and a hostname, returns a boolean answer indicating whether the IP belongs to a mail server of that domain. The algorithm I implemented used dig to search all mail servers of a domain and then tried to match any of them to the hostname associated with the given IP (which I found using dig -x). My program fails with the case I mentioned before. What am I missing?
Sorry for my bad english. Thanks!
Many services can run on one server/ipaddress, and many hostnames can resolve to one IP address. In the other direction, one ip address will most often resolve to only one hostname (if it has PTR record at all), and the name will very often be something generic like ip-xx-yy-zz-qq.networkcarrier.net (so unrelated to any of the services that are legitimately running on that server).
Depending on the purpose of your check, perhaps you can just test if the hostname A record points to the required IP address (because your initial requirement is flawed: ip addresses do not belong to domains, they belong to network providers).
(Still, for some purposes, most notably as anti spam measure, there is a use case for checking if ip address resolves to some particular hostname.)
I have a .csv file with a bunch of IP addresses. I am looking for a way to run a script to import the file and convert them to URLs and maybe export them to another .csv or something similar. Is this possible? How would I do this? Admittedly, I am a novice when it comes to python. I have done enough research to know that a call to sockets is involved, but that's where the trail ends. I don't know where to go from there. Any and all help is greatly appreciated. Thank you in advance.
You cannot convert them to specific URL's, but I guess you want to get the domain names. This is called Reverse DNS Lookup.
You can run this command nslookup <IP-ADDRESS> and get the domain name (besides other info).
Example:
nslookup 75.126.153.206
However, this does not guarantee that only that domain is associated with that IP. This is due to load balancers, and you will get the load balancer's domain name as a result most of the times. To avoid that you can try to do a Reverse IP Lookup. This will provide you all the domains associated with that IP address (online example https://hackertarget.com/reverse-ip-lookup).
Besides that, detecting the protocol (http/s, ftp) is another story. You have to scan the targets for specific ports like 80 (http), 443 (https), 21 (ftp) etc. to verify for they services they run. Again this does not guarantee that a service is definitively running on default ports (like web servers a lot of time may run on 8080 or some other port). To avoid that you may need to scan for a wider range of ports and detect their services which will be far more time consuming and you may get into trouble by getting your IP banned since somewhere this may be considered illegal.
Anyway for port scanning I suggest you to take a look at Nmap (https://nmap.org/)
import requests
def ip_to_url(ip):
try:
r = requests.get(f'http://{ip}', timeout=1).url
return r
except:
return 'not found'
print(ip_to_url('142.250.189.238'))
Output
http://www.google.com/
I want to get host name from ip. I know a few command who does the work like host, nslookup and dig but they are not completely reliable. In many of the cases they fail to give the host name. So, is there any command who can always give me the host name.
For ex: If I check "host stackoverflow.com" then it gives me a list of five different ip addresses. But when I check "host ip_address (each of the five different ip addresses)" than it's not able to find the host name.
DNS has a forward and reverse zones and what are you going to get by requesting a domain name for an IP-address depends on reverse DNS-zone configuration of that domain name, that's not an application malfunction or something - it's just asking DNS-servers. So no, there's no such command that you're looking for.
If you are not getting IP to hostname resolution, this means that the reverse lookup is either not allowed or not configured properly at the dns server (you are pointing to). In other words, PTR record does not exist, or you are not allowed access to it.
All the dns commands use the same or similar methods and underlying system calls to get the name; they search for the PTR record.
Without going into too much detail. If this is something you really want to do, you can look at other options like looking at the reconnaissance tools in Kali.
This might be a stupid question, but i run a business in a strip mall and internet is included (because of this I have no access to the router). the router assigns dynamic ip address and when I set a static ip I lose connection.
is there a way to change the address to my node app from "http:/ /[my-server-ip]:3000" to something like "http:/ /[business-name]:3000". (/ / should be // but stack wont let me post with dead links)
the main reason for this is I have multiple tablets and devices that use this system however recently after they made some changes to the routers setting my computer will be assigned two or three ip addresses a day (I notified the landlord he says its normal). and everytime my ip address changes I lose connection to my app.
is there a possible fix that doesnt require me to host on a web server or enable port forwarding?
perhaps I should reword the question. How do I go about setting up local dns zones from mac? (I know this can be achieved with most linux distros)
No you can't.
Your server IP will always change as the router gives you a new IP address, so change the hosts will not work unless every time the ip on the server changes, you change your ip as well on the devices.
You may try to create an account on dns sites like http://www.noip.com/. They will give you an "external" internet address like mybusiness.noip.com and then you will point your programs on tablets and cell phones to this address.
You will then install a program on your server that will tell noip what the new address is maintaining the same mybusiness.noip.com on them.
I am hoping there is a simple answer to this! My webserver has a number of IP addresses. one particular website has one of these IP addresses mapped to it. On said website, I have a java applet which is making outbound http requests.
Now, I am wondering what is the IP address that people will see for my server? Will they see the machine's default IP address or the IP address mapped in IIS for this website?
Java applet? So it's client side? It feels like a red herring.
The IP people will "see" (if they go looking) is whatever you set in the DNS, surely...
Perhaps you should specify which "people" you expect to see seeing your IP. If you mean the people owning the server you are making HTTPS requests to, and this is client side, they will see the IP of the website user. They won't see any of your IPs.
If this is server-side logic (ie something like a Java servlet), they will see whichever IP is the default outbound IP on that server. In some situations on some servers, the server will use the mapped IP, but as soon as you layer things out through connectors, it's anybody's guess which network adapter/IP actually gets used.
The java applet will be run by your visitors. So the IP address to be seen will be the visitor one and not one that your server owns.