Adds SSE-KMS and SSE-C config to S3 Objstore

CHANGELOG.md

@@ -13,6 +13,16 @@ We use *breaking* word for marking changes that are not backward compatible (rel
 
 :warning: **WARNING** :warning: Thanos Rule's `/api/v1/rules` endpoint no longer returns the old, deprecated `partial_response_strategy`. The old, deprecated value has been fixed to `WARN` for quite some time. _Please_ use `partialResponseStrategy`.
 
+:warning: **WARNING** :warning: The `sse_encryption` value is now deprecated in favour of `sse_config`. If you used `sse_encryption`, the migration strategy is to set up the following block:
+
+```yaml
+
+---
+sse_config:
+  type: SSE-S3
+```
+
+
 ### Fixed
 
 - [#2937](https://github.com/thanos-io/thanos/pull/2937) Receive: Fixing auto-configuration of --receive.local-endpoint
@@ -29,6 +39,7 @@ We use *breaking* word for marking changes that are not backward compatible (rel
 - [#2976](https://github.com/thanos-io/thanos/pull/2976) Query: Better rounding for incoming query timestamps.
 - [#2929](https://github.com/thanos-io/thanos/pull/2929) Mixin: Fix expression for 'unhealthy sidecar' alert and also increase the timeout for 10 minutes.
 - [#3024](https://github.com/thanos-io/thanos/pull/3024) Query: consider group name and file for deduplication
+- [#3064](https://github.com/thanos-io/thanos/pull/3064) s3: Add SSE/SSE-KMS/SSE-C configuration.
 
 ### Added
 

docs/storage.md

@@ -83,7 +83,6 @@ config:
   access_key: ""
   insecure: false
   signature_version2: false
-  encrypt_sse: false
   secret_key: ""
   put_user_metadata: {}
   http_config:
@@ -93,6 +92,11 @@ config:
   trace:
     enable: false
   part_size: 134217728
+  sse_config:
+    type: ""
+    kms_key_id: ""
+    kms_encryption_context: {}
+    encryption_key: ""
 ```
 
 At a minimum, you will need to provide a value for the `bucket`, `endpoint`, `access_key`, and `secret_key` keys. The rest of the keys are optional.
@@ -115,6 +119,38 @@ For debug and testing purposes you can set
 
 * `trace.enable: true` to enable the minio client's verbose logging. Each request and response will be logged into the debug logger, so debug level logging must be enabled for this functionality.
 
+#### S3 Server-Side Encryption
+
+SSE can be configued using the `sse_config`. [SSE-S3](https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingServerSideEncryption.html), [SSE-KMS](https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingKMSEncryption.html), and [SSE-C](https://docs.aws.amazon.com/AmazonS3/latest/dev/ServerSideEncryptionCustomerKeys.html) are supported.
+
+* If type is set to `SSE-S3` you do not need to configure other options.
+
+* If type is set to `SSE-KMS` you must set `kms_key_id`. The `kms_encryption_context` is optional, as [AWS provides a default encryption context](https://docs.aws.amazon.com/kms/latest/developerguide/services-s3.html#s3-encryption-context).
+
+* If type is set to `SSE-C` you must provide a path to the encryption key using `encryption_key`.
+
+If the SSE Config block is set but the `type` is not one of `SSE-S3`, `SSE-KMS`, or `SSE-C`, an error is raised.
+
+You will also need to apply the following AWS IAM policy for the user to access the KMS key:
+
+```json
+{
+    "Version": "2012-10-17",
+    "Statement": [
+        {
+            "Sid": "KMSAccess",
+            "Effect": "Allow",
+            "Action": [
+                "kms:GenerateDataKey",
+                "kms:Encrypt",
+                "kms:Decrypt"
+            ],
+            "Resource": "arn:aws:kms:<region>:<account>:key/<KMS key id>"
+        }
+    ]
+}
+```
+
 #### Credentials
 
 By default Thanos will try to retrieve credentials from the following sources:

pkg/objstore/s3/s3.go

@@ -9,6 +9,7 @@ import (
 	"crypto/tls"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net"
 	"net/http"
 	"os"
@@ -31,8 +32,19 @@ import (
 	"gopkg.in/yaml.v2"
 )
 
-// DirDelim is the delimiter used to model a directory structure in an object store bucket.
-const DirDelim = "/"
+const (
+	// DirDelim is the delimiter used to model a directory structure in an object store bucket.
+	DirDelim = "/"
+
+	// SSEKMS is the name of the SSE-KMS method for objectstore encryption.
+	SSEKMS = "SSE-KMS"
+
+	// SSEC is the name of the SSE-C method for objstore encryption.
+	SSEC = "SSE-C"
+
+	// SSES3 is the name of the SSE-S3 method for objstore encryption.
+	SSES3 = "SSE-S3"
+)
 
 var DefaultConfig = Config{
 	PutUserMetadata: map[string]string{},
@@ -53,13 +65,22 @@ type Config struct {
 	AccessKey       string            `yaml:"access_key"`
 	Insecure        bool              `yaml:"insecure"`
 	SignatureV2     bool              `yaml:"signature_version2"`
-	SSEEncryption   bool              `yaml:"encrypt_sse"`
 	SecretKey       string            `yaml:"secret_key"`
 	PutUserMetadata map[string]string `yaml:"put_user_metadata"`
 	HTTPConfig      HTTPConfig        `yaml:"http_config"`
 	TraceConfig     TraceConfig       `yaml:"trace"`
 	// PartSize used for multipart upload. Only used if uploaded object size is known and larger than configured PartSize.
-	PartSize uint64 `yaml:"part_size"`
+	PartSize  uint64    `yaml:"part_size"`
+	SSEConfig SSEConfig `yaml:"sse_config"`
+}
+
+// SSEConfig deals with the configuration of SSE for Minio. The following options are valid:
+// kmsencryptioncontext == https://docs.aws.amazon.com/kms/latest/developerguide/services-s3.html#s3-encryption-context
+type SSEConfig struct {
+	Type                 string            `yaml:"type"`
+	KMSKeyID             string            `yaml:"kms_key_id"`
+	KMSEncryptionContext map[string]string `yaml:"kms_encryption_context"`
+	EncryptionKey        string            `yaml:"encryption_key"`
 }
 
 type TraceConfig struct {
@@ -173,8 +194,32 @@ func NewBucketWithConfig(logger log.Logger, config Config, component string) (*B
 	client.SetAppInfo(fmt.Sprintf("thanos-%s", component), fmt.Sprintf("%s (%s)", version.Version, runtime.Version()))
 
 	var sse encrypt.ServerSide
-	if config.SSEEncryption {
-		sse = encrypt.NewSSE()
+	if config.SSEConfig.Type != "" {
+		switch config.SSEConfig.Type {
+		case SSEKMS:
+			sse, err = encrypt.NewSSEKMS(config.SSEConfig.KMSKeyID, config.SSEConfig.KMSEncryptionContext)
+			if err != nil {
+				return nil, errors.Wrap(err, "initialize s3 client SSE-KMS")
+			}
+
+		case SSEC:
+			key, err := ioutil.ReadFile(config.SSEConfig.EncryptionKey)
+			if err != nil {
+				return nil, err
+			}
+
+			sse, err = encrypt.NewSSEC(key)
+			if err != nil {
+				return nil, errors.Wrap(err, "initialize s3 client SSE-C")
+			}
+
+		case SSES3:
+			sse = encrypt.NewSSE()
+
+		default:
+			sseErrMsg := errors.Errorf("Unsupported type %q was provided. Supported types are SSE-S3, SSE-KMS, SSE-C", config.SSEConfig.Type)
+			return nil, errors.Wrap(sseErrMsg, "Initialize s3 client SSE Config")
+		}
 	}
 
 	if config.TraceConfig.Enable {
@@ -211,6 +256,15 @@ func validate(conf Config) error {
 	if conf.AccessKey != "" && conf.SecretKey == "" {
 		return errors.New("no s3 secret_key specified while access_key is present in config file; either both should be present in config or envvars/IAM should be used.")
 	}
+
+	if conf.SSEConfig.Type == SSEC && conf.SSEConfig.EncryptionKey == "" {
+		return errors.New("encryption_key must be set if sse_config.type is set to 'SSE-C'")
+	}
+
+	if conf.SSEConfig.Type == SSEKMS && conf.SSEConfig.KMSKeyID == "" {
+		return errors.New("kms_key_id must be set if sse_config.type is set to 'SSE-KMS'")
+	}
+
 	return nil
 }
 

pkg/objstore/s3/s3_test.go

@@ -24,6 +24,91 @@ insecure: false`)
 	}
 }
 
+func TestParseConfig_SSEConfig(t *testing.T) {
+	input := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-S3`)
+
+	cfg, err := parseConfig(input)
+	testutil.Ok(t, err)
+	testutil.Ok(t, validate(cfg))
+
+	input2 := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-C`)
+
+	cfg, err = parseConfig(input2)
+	testutil.Ok(t, err)
+	testutil.NotOk(t, validate(cfg))
+
+	input3 := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-C
+  kms_key_id: qweasd`)
+
+	cfg, err = parseConfig(input3)
+	testutil.Ok(t, err)
+	testutil.NotOk(t, validate(cfg))
+
+	input4 := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-C
+  encryption_key: /some/file`)
+
+	cfg, err = parseConfig(input4)
+	testutil.Ok(t, err)
+	testutil.Ok(t, validate(cfg))
+
+	input5 := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-KMS`)
+
+	cfg, err = parseConfig(input5)
+	testutil.Ok(t, err)
+	testutil.NotOk(t, validate(cfg))
+
+	input6 := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-KMS
+  kms_key_id: abcd1234-ab12-cd34-1234567890ab`)
+
+	cfg, err = parseConfig(input6)
+	testutil.Ok(t, err)
+	testutil.Ok(t, validate(cfg))
+
+	input7 := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-KMS
+  kms_key_id: abcd1234-ab12-cd34-1234567890ab
+  kms_encryption_context:
+    key: value
+    something: else
+    a: b`)
+
+	cfg, err = parseConfig(input7)
+	testutil.Ok(t, err)
+	testutil.Ok(t, validate(cfg))
+
+	input8 := []byte(`bucket: abdd
+endpoint: "s3-endpoint"
+sse_config:
+  type: SSE-MagicKey
+  kms_key_id: abcd1234-ab12-cd34-1234567890ab
+  encryption_key: /some/file`)
+
+	cfg, err = parseConfig(input8)
+	testutil.Ok(t, err)
+	// Since the error handling for "proper type" if done as we're setting up the bucket.
+	testutil.Ok(t, validate(cfg))
+}
+
 func TestParseConfig_DefaultHTTPConfig(t *testing.T) {
 	input := []byte(`bucket: abcd
 insecure: false`)