add resource aws kms policy attachment

.changelog/29923.txt

@@ -0,0 +1,3 @@
+```release-note:new-resource
+aws_kms_key_policy
+```

internal/conns/awsclient.go

@@ -53,3 +53,24 @@ func (client *AWSClient) CloudFrontDistributionHostedZoneID() string {
 	}
 	return "Z2FDTNDATAQYW2" // See https://docs.aws.amazon.com/Route53/latest/APIReference/API_AliasTarget.html#Route53-Type-AliasTarget-HostedZoneId
 }
+
+// DefaultKMSKeyPolicy returns the default policy for KMS keys in the configured AWS partition.
+func (client *AWSClient) DefaultKMSKeyPolicy() string {
+	return fmt.Sprintf(`
+{
+	"Id": "default",
+	"Version": "2012-10-17",
+	"Statement": [
+		{
+			"Sid": "Enable IAM User Permissions",
+			"Effect": "Allow",
+			"Principal": {
+				"AWS": "arn:%[1]s:iam::%[2]s:root"
+			},
+			"Action": "kms:*",
+			"Resource": "*"
+		}
+	]
+}	
+`, client.Partition, client.AccountID)
+}

internal/service/kms/key_policy.go

@@ -0,0 +1,123 @@
+package kms
+
+import (
+	"context"
+	"log"
+
+	"github.com/hashicorp/terraform-plugin-sdk/v2/diag"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/structure"
+	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/validation"
+	"github.com/hashicorp/terraform-provider-aws/internal/conns"
+	"github.com/hashicorp/terraform-provider-aws/internal/errs/sdkdiag"
+	"github.com/hashicorp/terraform-provider-aws/internal/tfresource"
+	"github.com/hashicorp/terraform-provider-aws/internal/verify"
+)
+
+// @SDKResource("aws_kms_key_policy")
+func ResourceKeyPolicy() *schema.Resource {
+	return &schema.Resource{
+		CreateWithoutTimeout: resourceKeyPolicyCreate,
+		ReadWithoutTimeout:   resourceKeyPolicyRead,
+		UpdateWithoutTimeout: resourceKeyPolicyUpdate,
+		DeleteWithoutTimeout: resourceKeyPolicyDelete,
+
+		Importer: &schema.ResourceImporter{
+			StateContext: schema.ImportStatePassthroughContext,
+		},
+
+		Schema: map[string]*schema.Schema{
+			"bypass_policy_lockout_safety_check": {
+				Type:     schema.TypeBool,
+				Optional: true,
+				Default:  false,
+			},
+			"key_id": {
+				Type:         schema.TypeString,
+				Required:     true,
+				ValidateFunc: validation.StringLenBetween(1, 2048),
+			},
+			"policy": {
+				Type:                  schema.TypeString,
+				Required:              true,
+				DiffSuppressFunc:      verify.SuppressEquivalentPolicyDiffs,
+				DiffSuppressOnRefresh: true,
+				ValidateFunc:          validation.StringIsJSON,
+				StateFunc: func(v interface{}) string {
+					json, _ := structure.NormalizeJsonString(v)
+					return json
+				},
+			},
+		},
+	}
+}
+
+func resourceKeyPolicyCreate(ctx context.Context, d *schema.ResourceData, meta interface{}) diag.Diagnostics {
+	var diags diag.Diagnostics
+	conn := meta.(*conns.AWSClient).KMSConn()
+
+	keyID := d.Get("key_id").(string)
+
+	if err := updateKeyPolicy(ctx, conn, keyID, d.Get("policy").(string), d.Get("bypass_policy_lockout_safety_check").(bool)); err != nil {
+		return sdkdiag.AppendErrorf(diags, "attaching KMS Key policy (%s): %s", keyID, err)
+	}
+
+	d.SetId(keyID)
+
+	return append(diags, resourceKeyPolicyRead(ctx, d, meta)...)
+}
+
+func resourceKeyPolicyRead(ctx context.Context, d *schema.ResourceData, meta interface{}) diag.Diagnostics {
+	var diags diag.Diagnostics
+	conn := meta.(*conns.AWSClient).KMSConn()
+
+	key, err := findKey(ctx, conn, d.Id(), d.IsNewResource())
+
+	if !d.IsNewResource() && tfresource.NotFound(err) {
+		log.Printf("[WARN] KMS Key (%s) not found, removing from state", d.Id())
+		d.SetId("")
+		return diags
+	}
+	if err != nil {
+		return sdkdiag.AppendErrorf(diags, "reading KMS Key (%s): %s", d.Id(), err)
+	}
+
+	d.Set("key_id", key.metadata.KeyId)
+
+	policyToSet, err := verify.PolicyToSet(d.Get("policy").(string), key.policy)
+	if err != nil {
+		return sdkdiag.AppendErrorf(diags, "while setting policy (%s), encountered: %s", key.policy, err)
+	}
+
+	d.Set("policy", policyToSet)
+
+	return diags
+}
+
+func resourceKeyPolicyUpdate(ctx context.Context, d *schema.ResourceData, meta interface{}) diag.Diagnostics {
+	var diags diag.Diagnostics
+	conn := meta.(*conns.AWSClient).KMSConn()
+
+	if d.HasChange("policy") {
+		if err := updateKeyPolicy(ctx, conn, d.Id(), d.Get("policy").(string), d.Get("bypass_policy_lockout_safety_check").(bool)); err != nil {
+			return sdkdiag.AppendErrorf(diags, "attaching KMS Key policy (%s): %s", d.Id(), err)
+		}
+	}
+
+	return append(diags, resourceKeyPolicyRead(ctx, d, meta)...)
+}
+
+func resourceKeyPolicyDelete(ctx context.Context, d *schema.ResourceData, meta interface{}) diag.Diagnostics {
+	var diags diag.Diagnostics
+	conn := meta.(*conns.AWSClient).KMSConn()
+
+	if !d.Get("bypass_policy_lockout_safety_check").(bool) {
+		if err := updateKeyPolicy(ctx, conn, d.Get("key_id").(string), meta.(*conns.AWSClient).DefaultKMSKeyPolicy(), d.Get("bypass_policy_lockout_safety_check").(bool)); err != nil {
+			return sdkdiag.AppendErrorf(diags, "attaching KMS Key policy (%s): %s", d.Id(), err)
+		} else {
+			log.Printf("[WARN] KMS Key Policy for Key (%s) does not allow PutKeyPolicy. Default Policy cannot be restored. Removing from state", d.Id())
+		}
+	}
+
+	return diags
+}