SecureRequest.GcpSecretManager 1.0.0

SecureRequest.GcpSecretManager

Google Cloud Secret Manager provider for the SecureRequest NuGet package.

Stores the RSA private key inside GCP Secret Manager instead of Redis/IDistributedCache, protected by IAM access control, Cloud Audit Logs, and optional CMEK encryption.

Installation

dotnet add package SecureRequest
dotnet add package SecureRequest.GcpSecretManager

Usage

Chain .WithGcpSecretManager() onto AddSecureRequest():

builder.Services
    .AddSecureRequest(builder.Configuration)
    .WithGcpSecretManager(projectId: "my-gcp-project");

Application Default Credentials (ADC) are used automatically — picks up Workload Identity in GKE, GOOGLE_APPLICATION_CREDENTIALS environment variable, and gcloud auth application-default login in development.

Custom secret ID

builder.Services
    .AddSecureRequest(builder.Configuration)
    .WithGcpSecretManager(
        projectId : "my-gcp-project",
        secretId  : "myapp-rsa-private-key");

Bring your own client (already in DI)

builder.Services.AddSingleton(SecretManagerServiceClient.Create());

builder.Services
    .AddSecureRequest(builder.Configuration)
    .WithGcpSecretManager(
        projectId     : "my-gcp-project",
        clientFactory : sp => sp.GetRequiredService<SecretManagerServiceClient>());

Required IAM permissions

Grant the service account running the application the following roles on the secret resource:

Minimum policy (after secret is created):

roles/secretmanager.secretAccessor
roles/secretmanager.secretVersionAdder

How it works

• First startup — if the secret doesn't exist, GcpSecretManagerKeyStorageProvider creates it (Automatic replication policy) and adds the first version.
• Subsequent startups — reads the latest version to load the private key.
• Key rotation — adds a new version. Previous versions remain accessible (useful for auditing) but latest points to the new key.

appsettings.json

No changes needed — SecureRequest options are bound from the same section:

"SecureRequest": {
  "Enabled": true,
  "EnableBodyEncryption": true,
  "EnableHmacSigning": true,
  "TimestampToleranceSeconds": 300,
  "NonceCacheTtlSeconds": 700,
  "SecuredMethods": ["POST", "PUT", "PATCH"],
  "ExcludedPaths": []
}

Note: IDistributedCache is still required for nonce anti-replay storage. Only the RSA private key moves to Secret Manager — nonces remain in Redis/in-memory cache.

Comparison

License

MIT