backerman/poudrierec2

Azure Functions-based C2 for Poudriere package building. (WIP)

PoudriereC2

© Brad Ackerman. MIT license.

Not an official Microsoft project. This README is not yet complete.

Setup

Load database

To log in with Azure Active Directory, specify the username as the tenant user (without the tenant domain) and set the password to a bearer token:

$Env:PGPASSWORD=(Get-AzAccessToken -ResourceUrl "https://ossrdbms-aad$((Get-AzContext).Environment.SqlDatabaseDnsSuffix)").Token

or

export PGPASSWORD=$(az account get-access-token --resource-type oss-rdbms --query "[accessToken]" -o tsv)

Redeploying the function

If the function is deleted and redeployed, its AAD managed service identity will have a different GUID, and PostgreSQL authentication will fail. To fix this issue, query AAD for the new GUID:

# Get the SP ID
az ad sp list --display-name ffpoudrierec2 --filter "servicePrincipalType eq 'ManagedIdentity'" --query '[].id'

Then open psql and update the role's security label:

security label for "pgaadauth" on role ffpoudrierec2 is 'aadauth,oid=<SP-GUID-goes-here>,type=service';

Discussion: Azure Database for PostgreSQL vs IaaS

CREATE USER poudrierec2 WITH PASSWORD '«some random and entropic password»';
GRANT poudriereadmin TO poudrierec2;

Azure Function

Authentication. Create new application.

Configuration -

• PostgresConnection: the connection string for the production database. (FIXME: support Key Vault)

Deployment:

dotnet publish --configuration Release /property:GenerateFullPaths=true /consoleloggerparameters:NoSummary 
func azure functionapp publish ffpoudrierec2

Azure Active Directory

Create application roles

Go to the AAD application created in the "Azure Function" step above. Select the "Create App Role" button and create three:

Display name	Value	Allowed member types	Description
Administrator	PoudriereC2.Administrator	Users/Groups	Read and modify all settings.
Viewer	PoudriereC2.Viewer	Users/Groups	Read all non-sensitive settings.
Worker node	PoudriereC2.WorkerNode	Applications	Obtain and report status of build jobs.

(FIXME: Use app manifest here instead?)

Select the application in the "Enterprise applications" blade. Under "Users and groups", add your user to the Administrator role.

Grant VM permission to call functions

It's not yet possible to grant a role to a managed identity from the portal, so you'll need to do it from the command line.

appId=$(az ad app list --display-name "PoudriereC2 API" --query '[0].appId' --output tsv)
appSPID=$(az ad sp show --id $appId --query 'objectId' --output tsv)
workerNodeRoleID=$(az ad app list --display-name PoudriereC2 --query "[0].appRoles[?value=='PoudriereC2.WorkerNode'].id | [0]" --output tsv)
workerSPID=$(az identity list --query "[?name=='poudriereidentity'].principalId | [0]" --output tsv)
az rest --method post \
    --uri "https://graph.microsoft.com/v1.0/servicePrincipals/${appSPID}/appRoleAssignedTo" \
    --body "{ \"principalId\": \"${workerSPID}\", \"appRoleId\": \"${workerNodeRoleID}\", \"resourceId\": \"${appSPID}\" }"

The az rest command will return an appRoleAssignment object and the poudriereidentity service principal will now appear in the application's "Users and Groups" blade.

Get MSI from worker and validate role present

Security

Local development

Install Azure Functions Core Tools. Then set PostgresConnection with the development database connection string and run func start in backend/Poudrierec2 to start the server.

In a different session, run yarn dev to start a webserver hosting the client after configuring the following variables:

Name	Value
NEXT_PUBLIC_AAD_CLIENT_ID	The client ID of the frontend's AAD application
NEXT_PUBLIC_AAD_TENANT_ID	The ID of the tenant containing the frontend application
NEXT_PUBLIC_API_BASE_URL	The URL of the development API server; normally http://localhost:7071/
NEXT_PUBLIC_IS_DEVELOPMENT	"TRUE" or "YES" (case-insensitive) iff a development instance
NEXT_PUBLIC_API_SCOPE	The API scope exposed by the Azure Function

poudrierec2's Issues

Ports tree model needs to match poudriere

Compare vs man poudrirere-ports.

Convert GUID parameters to Guid type

Azure Functions .NET SDK 1.5.1 now supports Guid parameters. Convert GUID parameters that are currently typed as String to Guid.