# Working with Security Groups in Amazon EC2
<a name="examples-ec2-security-groups"></a>

## Prerequisites
<a name="codeExamplePrereq"></a>

Before you begin, we recommend you read [Getting started using the AWS SDK for C\$1\$1](getting-started.md). 

Download the example code and build the solution as described in [Getting started on code examples](getting-started-code-examples.md). 

To run the examples, the user profile your code uses to make the requests must have proper permissions in AWS (for the service and the action). For more information, see [Providing AWS credentials](credentials.md).

## Create a Security Group
<a name="create-a-security-group"></a>

To create a security group, call the EC2Client’s `CreateSecurityGroup` function with a [CreateSecurityGroupRequest](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_create_security_group_request.html) that contains the key’s name.

 **Includes** 

```
#include <aws/ec2/EC2Client.h>
#include <aws/ec2/model/CreateSecurityGroupRequest.h>
```

 **Code** 

```
    Aws::EC2::EC2Client ec2Client(clientConfiguration);

    Aws::EC2::Model::CreateSecurityGroupRequest request;

    request.SetGroupName(groupName);
    request.SetDescription(description);
    request.SetVpcId(vpcID);

    const Aws::EC2::Model::CreateSecurityGroupOutcome outcome =
            ec2Client.CreateSecurityGroup(request);

    if (!outcome.IsSuccess()) {
        std::cerr << "Failed to create security group:" <<
                  outcome.GetError().GetMessage() << std::endl;
        return false;
    }

    std::cout << "Successfully created security group named " << groupName <<
              std::endl;
```

See the [complete example](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/cpp/example_code/ec2/create_security_group.cpp).

## Configure a Security Group
<a name="configure-a-security-group"></a>

A security group can control both inbound (ingress) and outbound (egress) traffic to your Amazon EC2 instances.

To add ingress rules to your security group, use the EC2Client’s `AuthorizeSecurityGroupIngress` function, providing the name of the security group and the access rules ([IpPermission](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_ip_permission.html)) you want to assign to it within an [AuthorizeSecurityGroupIngressRequest](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_authorize_security_group_ingress_request.html) object. The following example shows how to add IP permissions to a security group.

 **Includes** 

```
#include <aws/ec2/model/AuthorizeSecurityGroupIngressRequest.h>
```

 **Code** 

```
    Aws::EC2::Model::AuthorizeSecurityGroupIngressRequest authorizeSecurityGroupIngressRequest;
    authorizeSecurityGroupIngressRequest.SetGroupId(groupID);
```

```
    Aws::String ingressIPRange = "203.0.113.0/24";  // Configure this for your allowed IP range.
    Aws::EC2::Model::IpRange ip_range;
    ip_range.SetCidrIp(ingressIPRange);

    Aws::EC2::Model::IpPermission permission1;
    permission1.SetIpProtocol("tcp");
    permission1.SetToPort(80);
    permission1.SetFromPort(80);
    permission1.AddIpRanges(ip_range);

    authorize_request.AddIpPermissions(permission1);

    Aws::EC2::Model::IpPermission permission2;
    permission2.SetIpProtocol("tcp");
    permission2.SetToPort(22);
    permission2.SetFromPort(22);
    permission2.AddIpRanges(ip_range);

    authorize_request.AddIpPermissions(permission2);
```

```
    Aws::EC2::Model::AuthorizeSecurityGroupIngressOutcome authorizeSecurityGroupIngressOutcome =
            ec2Client.AuthorizeSecurityGroupIngress(authorizeSecurityGroupIngressRequest);

    if (authorizeSecurityGroupIngressOutcome.IsSuccess()) {
        std::cout << "Successfully authorized security group ingress." << std::endl;
    } else {
        std::cerr << "Error authorizing security group ingress: "
                  << authorizeSecurityGroupIngressOutcome.GetError().GetMessage() << std::endl;
    }
```

To add an egress rule to the security group, provide similar data in an [AuthorizeSecurityGroupEgressRequest](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_authorize_security_group_egress_request.html) to the EC2Client’s `AuthorizeSecurityGroupEgress` function.

See the [complete example](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/cpp/example_code/ec2/create_security_group.cpp).

## Describe Security Groups
<a name="describe-security-groups"></a>

To describe your security groups or get information about them, call the EC2Client’s `DescribeSecurityGroups` function with a [DescribeSecurityGroupsRequest](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_describe_security_groups_request.html).

You will receive a [DescribeSecurityGroupsResponse](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_describe_security_groups_response.html) in the outcome object that you can use to access the list of security groups by calling its `GetSecurityGroups` function, which returns a list of [SecurityGroup](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_security_group.html) objects.

 **Includes** 

```
#include <aws/ec2/EC2Client.h>
#include <aws/ec2/model/DescribeSecurityGroupsRequest.h>
#include <aws/ec2/model/DescribeSecurityGroupsResponse.h>
#include <iomanip>
#include <iostream>
```

 **Code** 

```
    Aws::EC2::EC2Client ec2Client(clientConfiguration);
    Aws::EC2::Model::DescribeSecurityGroupsRequest request;

    if (!groupID.empty()) {
        request.AddGroupIds(groupID);
    }

    Aws::String nextToken;
    do {
        if (!nextToken.empty()) {
            request.SetNextToken(nextToken);
        }

        Aws::EC2::Model::DescribeSecurityGroupsOutcome outcome = ec2Client.DescribeSecurityGroups(request);
        if (outcome.IsSuccess()) {
            std::cout << std::left <<
                      std::setw(32) << "Name" <<
                      std::setw(30) << "GroupId" <<
                      std::setw(30) << "VpcId" <<
                      std::setw(64) << "Description" << std::endl;

            const std::vector<Aws::EC2::Model::SecurityGroup> &securityGroups =
                    outcome.GetResult().GetSecurityGroups();

            for (const auto &securityGroup: securityGroups) {
                std::cout << std::left <<
                          std::setw(32) << securityGroup.GetGroupName() <<
                          std::setw(30) << securityGroup.GetGroupId() <<
                          std::setw(30) << securityGroup.GetVpcId() <<
                          std::setw(64) << securityGroup.GetDescription() <<
                          std::endl;
            }
        } else {
            std::cerr << "Failed to describe security groups:" <<
                      outcome.GetError().GetMessage() << std::endl;
            return false;
        }

        nextToken = outcome.GetResult().GetNextToken();
    } while (!nextToken.empty());
```

See the [complete example](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/cpp/example_code/ec2/describe_security_groups.cpp).

## Delete a Security Group
<a name="delete-a-security-group"></a>

To delete a security group, call the EC2Client’s `DeleteSecurityGroup` function, passing it a [DeleteSecurityGroupRequest](https://docs.aws.amazon.com/sdk-for-cpp/latest/api/aws-cpp-sdk-ec2/html/class_aws_1_1_e_c2_1_1_model_1_1_delete_security_group_request.html) that contains the ID of the security group to delete.

 **Includes** 

```
#include <aws/ec2/EC2Client.h>
#include <aws/ec2/model/DeleteSecurityGroupRequest.h>
#include <iostream>
```

 **Code** 

```
    Aws::EC2::EC2Client ec2Client(clientConfiguration);
    Aws::EC2::Model::DeleteSecurityGroupRequest request;

    request.SetGroupId(securityGroupID);
    Aws::EC2::Model::DeleteSecurityGroupOutcome outcome = ec2Client.DeleteSecurityGroup(request);

    if (!outcome.IsSuccess()) {
        std::cerr << "Failed to delete security group " << securityGroupID <<
                  ":" << outcome.GetError().GetMessage() << std::endl;
    } else {
        std::cout << "Successfully deleted security group " << securityGroupID <<
                  std::endl;
    }
```

See the [complete example](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/cpp/example_code/ec2/delete_security_group.cpp).

## More Information
<a name="more-information"></a>
+  [Amazon EC2 Security Groups](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-key-pairs.html) in the Amazon EC2 User Guide
+  [Authorizing Inbound Traffic for Your Linux Instances](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/authorizing-access-to-an-instance.html) in the Amazon EC2 User Guide
+  [CreateSecurityGroup](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_CreateSecurityGroup.html) in the Amazon EC2 API Reference
+  [DescribeSecurityGroups](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeSecurityGroups.html) in the Amazon EC2 API Reference
+  [DeleteSecurityGroup](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DeleteSecurityGroup.html) in the Amazon EC2 API Reference
+  [AuthorizeSecurityGroupIngress](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_AuthorizeSecurityGroupIngress.html) in the Amazon EC2 API Reference