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metasploit-gs/How-to-Send-an-HTTP-Request-Using-HTTPClient.md
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This is an example of how to write a module that uses the [HttpClient](https://dev.metasploit.com/api/Msf/Exploit/Remote/HttpClient.html) mixin to send a basic HTTP request.
### There are mainly two common methods you will see:
* **[send_request_raw](https://dev.metasploit.com/api/Msf/Exploit/Remote/HttpClient.html#send_request_raw-instance_method)** - You use this to send a raw HTTP request. Usually, you will want this method if you need something that violates the specification; in most other cases, you should prefer `send_request_cgi`. If you wish to learn about how this method works, look at the documentation for [`Rex::Proto::Http::Client#request_raw`](https://dev.metasploit.com/api/Rex/Proto/Http/Client.html#request_raw-instance_method).
Here's a basic example of how to use `send_request_raw`:
```ruby
send_request_raw({'uri'=>'/index.php'})
```
* **[send_request_cgi](https://dev.metasploit.com/api/Msf/Exploit/Remote/HttpClient.html#send_request_cgi-instance_method)** - You use this to send a higher-level HTTP request. For example, if your request contains a query string (or POST data), then you should use this. If you wish to learn about how this method works, check out [`Rex::Proto::Http::Client#request_cgi`](https://dev.metasploit.com/api/Rex/Proto/Http/Client.html#request_cgi-instance_method).
Both methods can automatically do the HTTP authentication if the user sets the "USERNAME" and "PASSWORD" advanced options.
Here's a very basic example for `send_request_cgi`:
```ruby
send_request_cgi({
'method' => 'GET',
'uri' => '/hello_world.php',
'vars_get' => {
'param_1' => 'abc',
'param_2' => '123'
}
})
```
**Please note**: `send_request_raw` and `send_request_cgi` will return a `nil` if there's a timeout, so please make sure to account for that condition when you handle the return value.
### URI Parsing
Before you send a HTTP request, you will most likely have to do some URI parsing. This is a tricky task, because sometimes when you join paths, you may accidentally get double slashes, like this: "/test//index.php". Or for some reason you have a missing slash. These are really commonly made mistakes. So here's how you can handle it safely:
1. Register your default URI datastore option as 'TARGETURI':
Example:
```ruby
register_options(
[
OptString.new('TARGETURI', [true, 'The base path to XXX application', '/xxx_v1/'])
], self.class)
```
2. Load your TARGETURI with [`target_uri`](https://dev.metasploit.com/api/Msf/Exploit/Remote/HttpClient.html#target_uri-instance_method), that way you get a real `URI` object:
In this example, we'll just load the path:
```ruby
uri = target_uri.path
```
3. When you want to join another URI, always use [`normalize_uri`](https://dev.metasploit.com/api/Msf/Exploit/Remote/HttpClient.html#normalize_uri-instance_method):
Example:
```ruby
# Returns: "/xxx_v1/admin/upload.php"
uri = normalize_uri(uri, 'admin', 'upload.php')
```
4. When you're done normalizing the URI, you're ready to use `send_request_cgi` or `send_request_raw`
Please note: The `normalize_uri` method will always follow these rules:
1. The URI should always begin with a slash.
2. You will have to decide if you need the trailing slash or not.
3. There should be no double slashes.
### Full Example
```ruby
require 'msf/core'
class Metasploit3 < Msf::Auxiliary
include Msf::Exploit::Remote::HttpClient
def initialize(info = {})
super(update_info(info,
'Name' => 'HttpClient Example',
'Description' => %q{
Do a send_request_cgi()
},
'Author' => [ 'sinn3r' ],
'License' => MSF_LICENSE
))
register_options(
[
OptString.new('TARGETURI', [true, 'The base path', '/'])
], self.class)
end
def run
uri = target_uri.path
res = send_request_cgi({
'method' => 'GET',
'uri' => normalize_uri(uri, 'admin', 'index.phpp'),
'vars_get' => {
'p1' => "This is param 1",
'p2' => "This is param 2"
}
})
if res && res.code == 200
print_good("I got a 200, awesome")
else
print_error("No 200, feeling blue")
end
end
end
```
### Common question(s):
1 - Can I use ```vars_get``` and ```vars_post``` together?
Yes. When you supply a hash to ```vars_get```, basically it means "put all this data in the query string". When you supply a hash to ```vars_post```, it means "put all this data in the body." All of them will be in the same request.