cli: support to declaratively set attestation policy

cli/internal/cloudcmd/BUILD.bazel

@@ -4,11 +4,11 @@ load("//bazel/go:go_test.bzl", "go_test")
 go_library(
     name = "cloudcmd",
     srcs = [
+        "attestationpolicy.go",
         "clients.go",
         "cloudcmd.go",
         "create.go",
         "iam.go",
-        "patch.go",
         "rollback.go",
         "terminate.go",
         "validators.go",
@@ -29,9 +29,6 @@ go_library(
         "//internal/config",
         "//internal/constants",
         "//internal/imagefetcher",
-        "@com_github_azure_azure_sdk_for_go//profiles/latest/attestation/attestation",
-        "@com_github_azure_azure_sdk_for_go_sdk_azcore//policy",
-        "@com_github_azure_azure_sdk_for_go_sdk_azidentity//:azidentity",
         "@com_github_hashicorp_terraform_json//:terraform-json",
         "@com_github_spf13_cobra//:cobra",
     ],
@@ -40,10 +37,10 @@ go_library(
 go_test(
     name = "cloudcmd_test",
     srcs = [
+        "attestationpolicy_test.go",
         "clients_test.go",
         "create_test.go",
         "iam_test.go",
-        "patch_test.go",
         "rollback_test.go",
         "terminate_test.go",
         "validators_test.go",

cli/internal/cloudcmd/attestationpolicy.go

@@ -0,0 +1,54 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+package cloudcmd
+
+import (
+	"encoding/base64"
+	"fmt"
+)
+
+// maaAttestationPolicy is the default attestation policy for Azure VMs on Constellation.
+const maaAttestationPolicy = `
+                version= 1.0;
+                authorizationrules
+                {
+                    [type=="x-ms-azurevm-default-securebootkeysvalidated", value==false] => deny();
+                    [type=="x-ms-azurevm-debuggersdisabled", value==false] => deny();
+                    // The line below was edited by the Constellation CLI. Do not edit manually.
+                    //[type=="secureboot", value==false] => deny();
+                    [type=="x-ms-azurevm-signingdisabled", value==false] => deny();
+                    [type=="x-ms-azurevm-dbvalidated", value==false] => deny();
+                    [type=="x-ms-azurevm-dbxvalidated", value==false] => deny();
+                    => permit();
+                };
+                issuancerules
+                {
+                };`
+
+// NewAzureMaaAttestationPolicy returns a new AzureAttestationPolicy to use with MAA.
+func NewAzureMaaAttestationPolicy() AzureAttestationPolicy {
+	return AzureAttestationPolicy{
+		policy: maaAttestationPolicy,
+	}
+}
+
+// AzureAttestationPolicy patches attestation policies on Azure.
+type AzureAttestationPolicy struct {
+	policy string
+}
+
+// Encode encodes the base64-encoded attestation policy in the JWS format specified here:
+// https://learn.microsoft.com/en-us/azure/attestation/author-sign-policy#creating-the-policy-file-in-json-web-signature-format
+func (p AzureAttestationPolicy) Encode() string {
+	encodedPolicy := base64.RawURLEncoding.EncodeToString([]byte(p.policy))
+	const header = `{"alg":"none"}`
+	payload := fmt.Sprintf(`{"AttestationPolicy":"%s"}`, encodedPolicy)
+
+	encodedHeader := base64.RawURLEncoding.EncodeToString([]byte(header))
+	encodedPayload := base64.RawURLEncoding.EncodeToString([]byte(payload))
+
+	return fmt.Sprintf("%s.%s.", encodedHeader, encodedPayload)
+}

cli/internal/cloudcmd/patch_test.go → cli/internal/cloudcmd/attestationpolicy_test.go

@@ -11,12 +11,12 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestEncodeAttestationPolicy(t *testing.T) {
+func TestAzureMaaAttestationPolicyEncode(t *testing.T) {
 	assert := assert.New(t)
 
-	p := AzurePolicyPatcher{}
+	p := NewAzureMaaAttestationPolicy()
 
 	// taken from <resource group url in the azure portal>/providers/Microsoft.Attestation/attestationProviders/<attestation provider name>/mrsg_item2
 	expected := "eyJhbGciOiJub25lIn0.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."
-	assert.Equal(expected, p.encodeAttestationPolicy())
+	assert.Equal(expected, p.Encode())
 }

cli/internal/cloudcmd/create.go

@@ -35,7 +35,6 @@ type Creator struct {
 	newTerraformClient func(ctx context.Context) (terraformClient, error)
 	newLibvirtRunner   func() libvirtRunner
 	newRawDownloader   func() rawDownloader
-	policyPatcher      policyPatcher
 }
 
 // NewCreator creates a new creator.
@@ -52,7 +51,6 @@ func NewCreator(out io.Writer) *Creator {
 		newRawDownloader: func() rawDownloader {
 			return imagefetcher.NewDownloader()
 		},
-		policyPatcher: NewAzurePolicyPatcher(),
 	}
 }
 
@@ -226,6 +224,7 @@ func (c *Creator) createAzure(ctx context.Context, cl terraformClient, opts Crea
 		ImageID:              opts.image,
 		SecureBoot:           *opts.Config.Provider.Azure.SecureBoot,
 		CreateMAA:            opts.Config.GetAttestationConfig().GetVariant().Equal(variant.AzureSEVSNP{}),
+		MAAPolicy:            NewAzureMaaAttestationPolicy().Encode(),
 		Debug:                opts.Config.IsDebugCluster(),
 	}
 
@@ -243,13 +242,6 @@ func (c *Creator) createAzure(ctx context.Context, cl terraformClient, opts Crea
 		return clusterid.File{}, err
 	}
 
-	if vars.CreateMAA {
-		// Patch the attestation policy to allow the cluster to boot while having secure boot disabled.
-		if err := c.policyPatcher.Patch(ctx, tfOutput.AttestationURL); err != nil {
-			return clusterid.File{}, err
-		}
-	}
-
 	return clusterid.File{
 		CloudProvider:  cloudprovider.Azure,
 		IP:             tfOutput.IP,
@@ -259,11 +251,6 @@ func (c *Creator) createAzure(ctx context.Context, cl terraformClient, opts Crea
 	}, nil
 }
 
-// policyPatcher interacts with the CSP (currently only applies for Azure) to update the attestation policy.
-type policyPatcher interface {
-	Patch(ctx context.Context, attestationURL string) error
-}
-
 // The azurerm Terraform provider enforces its own convention of case sensitivity for Azure URIs which Azure's API itself does not enforce or, even worse, actually returns.
 // Let's go loco with case insensitive Regexp here and fix the user input here to be compliant with this arbitrary design decision.
 var (

cli/internal/cloudcmd/create_test.go

@@ -33,7 +33,6 @@ func TestCreator(t *testing.T) {
 		libvirt               *stubLibvirtRunner
 		provider              cloudprovider.Provider
 		config                *config.Config
-		policyPatcher         *stubPolicyPatcher
 		wantErr               bool
 		wantRollback          bool // Use only together with stubClients.
 		wantTerraformRollback bool // When libvirt fails, don't call into Terraform.
@@ -65,7 +64,6 @@ func TestCreator(t *testing.T) {
 				cfg.RemoveProviderAndAttestationExcept(cloudprovider.Azure)
 				return cfg
 			}(),
-			policyPatcher: &stubPolicyPatcher{},
 		},
 		"azure trusted launch": {
 			tfClient: &stubTerraformClient{ip: ip},
@@ -77,18 +75,6 @@ func TestCreator(t *testing.T) {
 				}
 				return cfg
 			}(),
-			policyPatcher: &stubPolicyPatcher{},
-		},
-		"azure new policy patch error": {
-			tfClient: &stubTerraformClient{ip: ip},
-			provider: cloudprovider.Azure,
-			config: func() *config.Config {
-				cfg := config.Default()
-				cfg.RemoveProviderAndAttestationExcept(cloudprovider.Azure)
-				return cfg
-			}(),
-			policyPatcher: &stubPolicyPatcher{someErr},
-			wantErr:       true,
 		},
 		"azure newTerraformClient error": {
 			newTfClientErr: someErr,
@@ -98,8 +84,7 @@ func TestCreator(t *testing.T) {
 				cfg.RemoveProviderAndAttestationExcept(cloudprovider.Azure)
 				return cfg
 			}(),
-			policyPatcher: &stubPolicyPatcher{},
-			wantErr:       true,
+			wantErr: true,
 		},
 		"azure create cluster error": {
 			tfClient: &stubTerraformClient{createClusterErr: someErr},
@@ -109,7 +94,6 @@ func TestCreator(t *testing.T) {
 				cfg.RemoveProviderAndAttestationExcept(cloudprovider.Azure)
 				return cfg
 			}(),
-			policyPatcher:         &stubPolicyPatcher{},
 			wantErr:               true,
 			wantRollback:          true,
 			wantTerraformRollback: true,
@@ -213,7 +197,6 @@ func TestCreator(t *testing.T) {
 						destination: "some-destination",
 					}
 				},
-				policyPatcher: tc.policyPatcher,
 			}
 
 			opts := CreateOptions{
@@ -247,14 +230,6 @@ func TestCreator(t *testing.T) {
 	}
 }
 
-type stubPolicyPatcher struct {
-	patchErr error
-}
-
-func (s stubPolicyPatcher) Patch(_ context.Context, _ string) error {
-	return s.patchErr
-}
-
 func TestNormalizeAzureURIs(t *testing.T) {
 	testCases := map[string]struct {
 		in   terraform.AzureClusterVariables

cli/internal/cmd/upgradeapply.go

@@ -14,6 +14,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/edgelesssys/constellation/v2/cli/internal/cloudcmd"
 	"github.com/edgelesssys/constellation/v2/cli/internal/clusterid"
 	"github.com/edgelesssys/constellation/v2/cli/internal/helm"
 	"github.com/edgelesssys/constellation/v2/cli/internal/kubernetes"
@@ -253,6 +254,7 @@ func parseTerraformUpgradeVars(cmd *cobra.Command, conf *config.Config, fetcher
 			ImageID:              imageRef,
 			SecureBoot:           *conf.Provider.Azure.SecureBoot,
 			CreateMAA:            conf.GetAttestationConfig().GetVariant().Equal(variant.AzureSEVSNP{}),
+			MAAPolicy:            cloudcmd.NewAzureMaaAttestationPolicy().Encode(),
 			Debug:                conf.IsDebugCluster(),
 		}
 		return targets, vars, nil

cli/internal/terraform/terraform/azure/main.tf

@@ -48,17 +48,18 @@ resource "random_password" "initSecret" {
 resource "azurerm_attestation_provider" "attestation_provider" {
   count = var.create_maa ? 1 : 0
   # name must be between 3 and 24 characters in length and use numbers and lower-case letters only.
-  name                = format("constell%s", local.uid)
-  resource_group_name = var.resource_group
-  location            = var.location
+  name                   = format("constell%s", local.uid)
+  resource_group_name    = var.resource_group
+  location               = var.location
+  azure_vm_policy_base64 = var.maa_policy
 
   lifecycle {
     # Attestation policies will be set automatically upon creation, even if not specified in the resource,
     # while they aren't being incorporated into the Terraform state correctly.
     # To prevent them from being set to null when applying an upgrade, ignore the changes until the issue
     # is resolved by Azure.
     # Related issue: https://github.com/hashicorp/terraform-provider-azurerm/issues/21998
-    ignore_changes = [open_enclave_policy_base64, sgx_enclave_policy_base64, tpm_policy_base64]
+    ignore_changes = [open_enclave_policy_base64, sgx_enclave_policy_base64, tpm_policy_base64, azure_vm_policy_base64, sev_snp_policy_base64]
   }
 }
 

cli/internal/terraform/terraform/azure/variables.tf

@@ -69,6 +69,11 @@ variable "create_maa" {
   description = "Whether to create a Microsoft Azure attestation provider."
 }
 
+variable "maa_policy" {
+  type        = string
+  description = "Base64-encoded Attestation policy for the Microsoft Azure attestation provider."
+}
+
 variable "debug" {
   type        = bool
   default     = false

cli/internal/terraform/variables.go

@@ -183,6 +183,8 @@ type AzureClusterVariables struct {
 	SecureBoot bool
 	// CreateMAA sets whether a Microsoft Azure attestation provider should be created.
 	CreateMAA bool
+	// MAAPolicy sets the base64-encoded policy for the Microsoft Azure attestation provider.
+	MAAPolicy string
 	// Debug is true if debug mode is enabled.
 	Debug bool
 }
@@ -200,6 +202,7 @@ func (v *AzureClusterVariables) String() string {
 	writeLinef(b, "confidential_vm = %t", v.ConfidentialVM)
 	writeLinef(b, "secure_boot = %t", v.SecureBoot)
 	writeLinef(b, "create_maa = %t", v.CreateMAA)
+	writeLinef(b, "maa_policy = %q", v.MAAPolicy)
 	writeLinef(b, "debug = %t", v.Debug)
 
 	return b.String()