From a5320408a5dc80e7ebd15757287789ac3d17ddfd Mon Sep 17 00:00:00 2001
From: Alex Vanin <alexey@nspcc.ru>
Date: Wed, 23 Dec 2020 12:54:34 +0300
Subject: [PATCH] [#271] service/audit: Implement PoR

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
---
 pkg/innerring/rpc.go                  |   2 +
 pkg/services/audit/auditor/context.go |  10 +++
 pkg/services/audit/auditor/exec.go    |   4 -
 pkg/services/audit/auditor/por.go     | 103 ++++++++++++++++++++++++++
 4 files changed, 115 insertions(+), 4 deletions(-)
 create mode 100644 pkg/services/audit/auditor/por.go

diff --git a/pkg/innerring/rpc.go b/pkg/innerring/rpc.go
index ec730fd5c..42b342629 100644
--- a/pkg/innerring/rpc.go
+++ b/pkg/innerring/rpc.go
@@ -90,6 +90,7 @@ func (c *ClientCache) GetSG(task *audit.Task, id *object.ID) (*storagegroup.Stor
 
 		cctx, cancel := context.WithTimeout(task.AuditContext(), c.sgTimeout)
 		obj, err := cli.GetObject(cctx, getParams)
+
 		cancel()
 
 		if err != nil {
@@ -135,6 +136,7 @@ func (c *ClientCache) GetHeader(task *audit.Task, node *netmap.Node, id *object.
 
 	cctx, cancel := context.WithTimeout(task.AuditContext(), c.headTimeout)
 	head, err := cli.GetObjectHeader(cctx, headParams, client.WithTTL(1))
+
 	cancel()
 
 	if err != nil {
diff --git a/pkg/services/audit/auditor/context.go b/pkg/services/audit/auditor/context.go
index 8b9bd53f3..de49e82ea 100644
--- a/pkg/services/audit/auditor/context.go
+++ b/pkg/services/audit/auditor/context.go
@@ -17,6 +17,12 @@ type Context struct {
 	task *audit.Task
 
 	report *audit.Report
+
+	// consider adding mutex to access caches
+
+	sgMembersCache map[int][]*object.ID
+
+	placementCache map[string][]netmap.Nodes
 }
 
 // ContextPrm groups components required to conduct data audit checks.
@@ -77,6 +83,10 @@ func (c *Context) containerID() *container.ID {
 func (c *Context) init() {
 	c.report = audit.NewReport(c.containerID())
 
+	c.sgMembersCache = make(map[int][]*object.ID)
+
+	c.placementCache = make(map[string][]netmap.Nodes)
+
 	c.log = c.log.With(
 		zap.Stringer("container ID", c.task.ContainerID()),
 	)
diff --git a/pkg/services/audit/auditor/exec.go b/pkg/services/audit/auditor/exec.go
index 5ed605b74..81c1cdbb2 100644
--- a/pkg/services/audit/auditor/exec.go
+++ b/pkg/services/audit/auditor/exec.go
@@ -34,10 +34,6 @@ func (c *Context) Execute() {
 	c.writeReport()
 }
 
-func (c *Context) executePoR() {
-	// TODO: implement me
-}
-
 func (c *Context) executePoP() {
 	// TODO: implement me
 }
diff --git a/pkg/services/audit/auditor/por.go b/pkg/services/audit/auditor/por.go
new file mode 100644
index 000000000..f2a703616
--- /dev/null
+++ b/pkg/services/audit/auditor/por.go
@@ -0,0 +1,103 @@
+package auditor
+
+import (
+	"bytes"
+
+	"github.com/nspcc-dev/neofs-api-go/pkg/object"
+	"github.com/nspcc-dev/neofs-node/pkg/services/object_manager/placement"
+	"github.com/nspcc-dev/tzhash/tz"
+	"go.uber.org/zap"
+)
+
+func (c *Context) executePoR() {
+	for i, sg := range c.task.StorageGroupList() {
+		c.checkStorageGroupPoR(i, sg) // consider parallel it
+	}
+}
+
+func (c *Context) checkStorageGroupPoR(ind int, sg *object.ID) {
+	storageGroup, err := c.cnrCom.GetSG(c.task, sg) // get storage group
+	if err != nil {
+		c.log.Warn("can't get storage group",
+			zap.Stringer("sgid", sg),
+			zap.String("error", err.Error()))
+
+		return
+	}
+
+	members := storageGroup.Members()
+	c.sgMembersCache[ind] = members
+
+	var (
+		tzHash    []byte
+		totalSize uint64
+	)
+
+	for i := range members {
+		objectPlacement, err := placement.BuildObjectPlacement(
+			c.task.NetworkMap(),
+			c.task.ContainerNodes(),
+			members[i],
+		)
+		if err != nil {
+			c.log.Info("can't build placement for storage group member",
+				zap.Stringer("sg", sg),
+				zap.Stringer("member_id", members[i]),
+			)
+
+			continue
+		}
+
+		c.placementCache[members[i].String()] = objectPlacement
+
+		for _, node := range placement.FlattenNodes(objectPlacement) {
+			hdr, err := c.cnrCom.GetHeader(c.task, node, members[i])
+			if err != nil {
+				c.log.Debug("can't head object",
+					zap.String("remote_node", node.Address()),
+					zap.Stringer("oid", members[i]))
+
+				continue
+			}
+
+			if len(tzHash) == 0 {
+				tzHash = hdr.PayloadHomomorphicHash().Sum()
+			} else {
+				tzHash, err = tz.Concat([][]byte{
+					tzHash,
+					hdr.PayloadHomomorphicHash().Sum(),
+				})
+				if err != nil {
+					c.log.Debug("can't concatenate tz hash",
+						zap.Stringer("oid", members[i]),
+						zap.String("error", err.Error()))
+
+					break
+				}
+			}
+
+			totalSize += hdr.PayloadSize()
+
+			break
+		}
+	}
+
+	sizeCheck := storageGroup.ValidationDataSize() == totalSize
+	tzCheck := bytes.Equal(tzHash, storageGroup.ValidationDataHash().Sum())
+
+	if sizeCheck && tzCheck {
+		c.report.PassedPoR(sg) // write report
+	} else {
+		if !sizeCheck {
+			c.log.Debug("storage group size check failed",
+				zap.Uint64("expected", storageGroup.ValidationDataSize()),
+				zap.Uint64("got", totalSize))
+		}
+
+		if !tzCheck {
+			c.log.Debug("storage group tz hash check failed")
+		}
+
+		c.report.FailedPoR(sg) // write report
+	}
+}