From 4b1eb63b59b9ca92e9d90bdcf7c0d3692c1a0082 Mon Sep 17 00:00:00 2001
From: Stanislav Bogatyrev <stanislav@nspcc.ru>
Date: Tue, 11 Aug 2020 17:49:31 +0300
Subject: [PATCH] [#37] Add matryoska-style meta and verification headers

Signed-off-by: Stanislav Bogatyrev <stanislav@nspcc.ru>
---
 service/meta.proto   | 49 ++++++++++++++++++++++++++++++++------------
 service/verify.proto | 22 +++++++++++++-------
 2 files changed, 51 insertions(+), 20 deletions(-)

diff --git a/service/meta.proto b/service/meta.proto
index ff5ceac..77e5793 100644
--- a/service/meta.proto
+++ b/service/meta.proto
@@ -5,6 +5,16 @@ package service;
 option go_package = "github.com/nspcc-dev/neofs-api-go/service";
 option csharp_namespace = "NeoFS.API.Service";
 
+import "acl/types.proto";
+import "service/verify.proto";
+
+message XHeader {
+  // Key of the X-Header.
+  string key = 1;
+  // Value of the X-Header.
+  string value = 2;
+}
+
 // Represents API version used by node.
 message Version {
   // Major API version.
@@ -13,19 +23,32 @@ message Version {
   uint32 minor = 2;
 }
 
-// RequestMetaHeader contains information about request meta headers.
+// Information about the request
 message RequestMetaHeader {
-  // Carries maximum number of nodes in the request route.
-  uint32 ttl = 1;
+  // Client API version.
+  Version version = 1;
+  // Client local epoch number. Set to 0 if unknown.
+  uint64 epoch = 2;
+  // Maximum number of nodes in the request route.
+  uint32 ttl = 3;
+  // Request X-Headers.
+  repeated XHeader x_headers = 4;
 
-  message XHeader {
-    // Carries key to the X-Header.
-    string key = 1;
-
-    // Carries value of the X-Header.
-    string value = 2;
-  }
-
-  // Carries request X-Headers.
-  repeated XHeader x_headers = 2;
+  // RequestMetaHeader of the origin request.
+  RequestMetaHeader origin = 98;
+}
+
+// Information about the response
+message ResponseMetaHeader {
+  // Server API version.
+  Version version = 1;
+  // Server local epoch number.
+  uint64 epoch = 2;
+  // Maximum number of nodes in the response route.
+  uint32 ttl = 3;
+  // Response X-Headers.
+  repeated XHeader x_headers = 4;
+
+  // Carries response meta header of the origin response.
+  ResponseMetaHeader origin = 98;
 }
diff --git a/service/verify.proto b/service/verify.proto
index 4ae10a9..a1deab8 100644
--- a/service/verify.proto
+++ b/service/verify.proto
@@ -15,17 +15,17 @@ message Signature {
   bytes sign = 2;
 }
 
-// RequestVerificationHeader is a set of signatures of every NeoFS Node that
-// processed request.
+// Verification info for request signed by all intermediate nodes
 message RequestVerificationHeader {
-  // Signatures is a set of signatures of every passed NeoFS Node
-  repeated Signature signatures = 1;
+  Signature body_signature = 1;
+  Signature meta_signature = 2;
 
   // Token is a token of the session within which the request is sent
-  SessionToken token = 2;
-
+  SessionToken token = 3;
   // Bearer is a Bearer token of the request
-  BearerTokenMsg bearer = 3;
+  BearerTokenMsg bearer = 4;
+
+  RequestVerificationHeader origin = 5;
 }
 
 // Represents the NeoFS session token.
@@ -112,3 +112,11 @@ message BearerTokenMsg {
   // Signature is a signature of token information
   bytes signature = 3;
 }
+
+// Verification info for response signed by all intermediate nodes
+message ResponseVerificationHeader {
+  Signature body_signature = 1;
+  Signature meta_signature = 2;
+
+  ResponseVerificationHeader origin = 3;
+}