# Advanced SIP Testing with sipp$

## Section 1: Installation and Configuration on Kali Linux

### 1.1 Overview of SIP Testing with sipp$

The Session Initiation Protocol (SIP) is widely used for setting up voice and video calls over the Internet. sipp$ is a powerful tool for testing SIP protocols, allowing penetration testers and network administrators to simulate SIP traffic, conduct performance testing, and identify vulnerabilities in SIP implementations. As a white-hat pentester, mastering tools like sipp$ can help you secure VoIP systems against potential attacks.

### 1.2 Installing sipp$ on Kali Linux

Before you start using sipp$, you need to install it on your Kali Linux system. Here’s a step-by-step guide:

1. **Update Your Package Repository:**
Open your terminal and ensure that your package list is up-to-date. Run the following command:

2. **Install sipp$:**
You can easily install sipp$ using the following command:

3. **Verify Installation:**
After installation, verify that sipp$ is installed correctly by checking its version. Run:


This command should display the version of sipp$ installed on your system.

### 1.3 Configuration of sipp$

While sipp$ can be used with its default settings, you may want to configure it for specific testing. Here are a few essential configuration options:

1. **Configuration Files:**
sipp$ comes with several predefined xml files for scenarios. You can edit these or create your own in the `/usr/share/sipp/` directory.

2. **Setting Up a Custom SIP Scenario:**
If you wish to define specific SIP messages and their responses, you can create an XML file. A basic example is:

[/dm_code_snippet]xml










[/dm_code_snippet]

3. **Running sipp$ with Custom Configurations:**
To run sipp$ with your custom scenario, use the following command:


sipp -sf your_scenario.xml -m 1 -s 101 local-sip-server

## Step-by-Step Usage of sipp$

### 2.1 Basic Usage Scenarios

The following are some common usage scenarios for sipp$ along with step-by-step instructions:

#### 2.1.1 Basic INVITE/ACK Test

1. **Define Your SIP Server:**
Specify the SIP server you want to test. Replace `local-sip-server` with your SIP server's IP or hostname.

2. **Run the Command:**

This command sets sipp$ to act as a User Agent Server (UAS) listening on port 5060.

3. **Simulate a Call:**
In another terminal, initiate a call from a User Agent Client (UAC):

4. **Observe the Traffic:**
Use tools like Wireshark or tcpdump to capture and analyze SIP packets.

### 2.2 Real-World Use Cases

#### 2.2.1 Penetration Testing VoIP Systems

Using sipp$ for penetration tests can help identify security weaknesses such as:

– **SIP INVITE Flooding:**
Simulate a DoS attack by flooding the SIP server with INVITE requests. Run:


sipp -sn uac -r 10 -rp 2 local-sip-server:5060

In this command, `-r` indicates the number of calls per second, and `-rp` indicates the rate of calls generated.

– **Authentication Testing:**
Test for weak credentials by brute-forcing registration attempts:


sipp -sf register.xml -m 10 local-sip-server:5060

Ensure you have explicit permission before performing such tests.

#### 2.2.2 Load Testing SIP Servers

Load testing is crucial for assessing how SIP servers handle high traffic. Use sipp$ to simulate multiple calls:

1. **Simulate Multiple Call Flows:**


sipp -sn uac -m 100 -r 10 local-sip-server:5060

This command initiates 100 calls at a rate of 10 calls per second.

2. **Monitor Server Response:**
Check server logs or use performance monitoring tools to assess the server's capacity under load.

## Detailed Technical Explanations

### 3.1 SIP Protocol Structure

Understanding the structure of SIP messages is essential for effective testing. SIP is a text-based protocol, similar to HTTP, consisting of:

– **Requests:**
Requests are initiated by a client and can include methods such as INVITE, BYE, REGISTER, and ACK.

– **Responses:**
Responses from the server indicate the status of the request. They are categorized by response codes, e.g., 200 OK, 404 Not Found.

### 3.2 SIP Message Flow

To understand how to craft effective tests, it’s important to recognize the typical SIP message flow:

1. **Registration:**
Clients register their contact information with a SIP server.
2. **Call Setup:**
The INVITE request is used to initiate a call.
3. **Call Management:**
During a call, multiple methods like BYE (to end a call) and OPTIONS (to check the capabilities of a server) are used.
4. **Termination:**
Calls can be terminated gracefully with a BYE message.

## External Reference Links

– [SIP Protocol Overview – IETF](https://tools.ietf.org/html/rfc3261)
– [sipp$ Official Documentation](https://sipp.sourceforge.net/)
– [VoIP Security Best Practices](https://www.cisecurity.org/white-papers/voip-security-best-practices/)

By mastering these concepts and hands-on practices with sipp$, you will establish a strong foundation in SIP security testing, allowing you to proactively defend against potential vulnerabilities in VoIP systems.

Made by pablo rotem / פבלו רותם

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