Azure Storage Blob and Queue Secured access to external Application - azure

I have a Storage account in our Azure "https://MysecuredStorageaccount.blob.core.windows.net" where we need to provide access to an external vendor to push the data to our blob. Since it is a PAAS service by default it is accessible with "Shared access Signature" .
However, as part of Security compliance policy in our ORG, i can not allow any service publicly accessible, so i have created a private end points to access Storage account internally.
Do we have any other Network Firewall Solution to allow blob access to external vendor application that too without whitelisting their Public IP in Storage account Network Firewall.
Any Firewall/NAT kind of solution that can be used to provide a secured connection externally.

If it's being accessed manually or from a specific machine/user you can consider Azure Point-to-Site with a VPN Gateway else look into a Site-to-site VPN setup with the vendors firewall.
It's not that hard to setup and will give them access directly to the subnet/IP of your choice. The setup complexity would depend on the firewall the vendor uses but in general its not too bad.
That's the easiest option I can think of.

Related

Is my web app & table storage sufficiently secured from public facing internet?

Intro:
I have an asp.net core app service hosted in Azure.
This app service has an API controller that reads/writes to an Azure Table Storage.
The code for this is using Azure.Data.Table library w/ an Access Key that i setup from the Azure portal (for the table storage).
Now, under the storage account / Networking blade, I have selected the "Enabled from All Networks".
Question:
Does this mean this storage account is open to the entire internet? I am confused whether this is secured because my code is accessing it via the Access Key (which I mentioned above).
Thank you.
Regarding the settings above, Enabled from all networks means the storage account endpoints (i.e. blob, table, queue, etc.) will accept traffic from the internet but you still need access key to view any data.
Enabled from selected virtual networks and IP address means that traffic will only be allowed from resources on the same VNET or specific IP address that you've configured e.g. your local device public IP provided by your ISP. This is a more secured method because you essentially whitelisting your what can connect.
Disabled means nothing outside of Azure can access the storage account and you will connect via Private Endpoint.
If your access key is inside your code, then this isn't the best secured method. You would want to have your connection with access key in either Application Settings so it can be retrieved as an environment variable or through Azure Key Vault. Using Key Vault allows you dictate what service or user can retrieve that value.
I will suggest assigning the system assigned managed identity to the app Service. Then use the resource instance rules for storage setting to configure the firewall https://learn.microsoft.com/en-us/azure/storage/common/storage-network-security?tabs=azure-portal#grant-access-from-azure-resource-instances

Subnet Delegation and Service Endpoints for Azure SQL Database in a vnet?

If I am setting up an Azure SQL Database in a vnet which Azure App Service and Azure Function will access. Is using both Subnet Delegation and Service Endpoints the right way to go? I didn't fully understand the documentation.
Regarding subnet delegation, I read this Microsoft article and this stackoverflow post, which stated:
When you delegate a subnet to an Azure service, you allow that service to establish some basic network configuration rules for that subnet, which help the Azure service operate their instances in a stable manner.
That sounds like a good thing but makes me wonder how it worked efficiently w/o subnet delegation.
As for Service Endpoints, I read this Microsoft article, which states:
Virtual Network (VNet) service endpoint provides secure and direct connectivity to Azure services over an optimized route over the Azure backbone network. Endpoints allow you to secure your critical Azure service resources to only your virtual networks. Service Endpoints enables private IP addresses in the VNet to reach the endpoint of an Azure service without needing a public IP address on the VNet.
Does that mean I cannot reach the Azure SQL Database from my home machine w/a firewall rule?
They both sound like they have the same benefits and I'm struggling to understand the difference. I suppose the larger question is should I enable both for the simple architecture outlined above.
In the Microsoft service endpoints documentation they also mention:
Microsoft recommends use of Azure Private Link for secure and private access to services hosted on Azure platform. For more information, see Azure Private Link.
For some reason that seems like an Azure to on-premise thing.
• You cannot use a ‘Subnet Delegation’ along with a ‘Private endpoint’ since that subnet is delegated for the said service, in your case, the Azure SQL Database. Through a subnet delegation, you can define the NSG association for it, as well as associate multiple delegated subnets to a common NSG. You can also define the IP Address space for the delegated subnet, the route table association with it, the custom DNS entry configuration in Azure DNS as well as define the minimum number of IP Addresses available for that delegated subnet. Similarly, with regards to service endpoint, these stated functions are not available.
• In service endpoint, you do not have control over the routing mechanism as well as the IP address related allotment, reservation, or configuration. Also, managing DNS entries for the resources managed through them and controlling them through a firewall or NAT gateway isn’t required unlike a subnet delegation because all these things are managed by Microsoft Azure’s backbone network on your behalf.
Thus, both have their own features and specifications for enabling you to configure according to your own requirements.
Does that mean I cannot reach the Azure SQL Database from my home machine w/a firewall rule?
Yes, you will have to create a firewall rule to allow the access from on-premises system to Azure SQL Server/Database and configure the service endpoint accordingly to allow the VPN client IP Addresses for accessing the same over public internet.
Also, through Azure private link, you won’t be able to connect from on-premises to Azure as it uses a private IP address and a private DNS zone entry related to it to connect to Azure resources in the same virtual network.
To know more regarding the configuration of Azure service access from on-premises network, kindly refer to the below given link: -
https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-service-endpoints-overview#secure-azure-service-access-from-on-premises
Also, refer to the below snapshots regarding the configuration and selection of service endpoint for a particular subnet: -

Azure Storage firewall open to Azure App Service

I have an Azure Storage account and need to enable the storage firewall.
I have added the outbound IP addresses of my App Service, but the firewall still prevents access. (I know that these addresses can change, but they change predictably, so I can live with that.)
Is there a solution to grant an App Service access to the Storage account other than disabling the firewall (and other than using an ASE, which isn't an option)?
So it turns out that in a new Azure Storage account with a new App Service, setting the storage firewall to the outbound IPs of the App Service does work as expected. Unless the client browser is actually doing the download, adding the client's IP is not required.
Edit
This only works reliably when the storage account is in a different data centre to the App Service. When they are both in the same data centre, an internal outbound address (e.g. 10.x.x.x) is presented from the App Service to the Storage account. Internal addresses cannot be added to the Storage firewall.
If you access your web app service from on-premises networks, you need to grant access from your on-premise networks to your storage account with a public Internet-facing IP address used by your network. You can get more details from Grant access from an internet IP range
If you have VNet Integration with your apps. You should first enable service endpoints for storage in the VNet. You can refer to Grant access from a virtual network.

How do I restrict the clients that can access my Azure App Service?

Given that I create an Azure 'App Service'
How do I ensure that this service is only callable from ...
A.> 2 existing external servers (whose IP addresses will be known)
B.> 3 other App Services which I will be creating, but whose IP Addresses may not be known since I may need to scale those out (Over multiple additional instances)
To clarify... Is there some Azure service that will allow me to treat this collective of machines (both real and virtual) as a single group, such that I can apply some test on incoming requests to see if they originate from this group?
on Azure WebApps, You may wish to know; the IP Restrictions (https://learn.microsoft.com/en-us/azure/app-service/app-service-ip-restrictions) allow you to define a list of IP addresses that are allowed to access your app. The allow list can include individual IP addresses or a range of IP addresses defined by a subnet mask. When a request to the app is generated from a client, the IP address is evaluated against the allow list. If the IP address is not in the list, the app replies with an HTTP 403 status code.
You can use IP and Domain Restrictions to control the set of IP addresses, and address ranges, that are either allowed or denied access to in your websites. With Azure WebApps you can enable/disable the feature, as well as customize its behavior, using web.config files located in their website.
Additionally, VNET Integration gives your web app access to resources in your virtual network but does not grant private access to your web app from the virtual network. Private site access is only available with an ASE configured with an Internal Load Balancer (ILB).
If you haven’t checked this already, checkout Integrate your app with an Azure Virtual Network for more details on VNET Integration (https://learn.microsoft.com/en-us/azure/app-service/web-sites-integrate-with-vnet)
I strongly suggest dropping the whole what's my IP approach and throwing in OAuth. Azure AD gives you access tokens with moderate effort —
Service to service calls using client credentials (shared secret or certificate)
Else, TLS client authentication would be next on my list. Although that tends to really suck if you have to deal with several programming stacks, TLS offloaders and what not.

Access Azure Storage from Azure VM without outbound internet

I have VNET with DMZ and multiple internal subnets configured. There is security requirement to block all the outbound internet connection for the internal subnets.
Now, this VM needs to access Azure blob storage which hosted in the same region.
I am wondering to access Azure Blob storage without outbound internet connection.
Pondering on questions like
1) Can I attach Azure Storage account in my azure VNET
2) Can there is existing solution, where I am access internet via JUMP-BOX network configuration, where my VM internet traffic goes via Jump box
3) Can this be achieve via Network ACLs or some better solution?
Now, this question is mix of networking and azure services, not sure of the right forum for this, server-fault or stack-overflow?
Azure Storage uses a public endpoint, as it's a multi-tenant service. You cannot add your Azure storage account to your VNet, since this is not an endpoint you control.
You'll need to access storage directly, via its <storagename>.blob.core.windows.net endpoint. How you ultimately accomplish that is up to you.

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