swarm/storage/mru: Client-side MRU signatures (#784)

* swarm/storage/mru: Add embedded publickey and remove ENS dep

This commit breaks swarm, swarm/api...
but tests in swarm/storage/mru pass

* swarm: Refactor swarm, swarm/api to mru changes, make tests pass

* swarm/storage/mru: Remove self from recv, remove test ens vldtr

* swarm/storage/mru: Remove redundant test, expose ResourceHash mthd

* swarm/storage/mru: Make HeaderGetter mandatory + godoc fixes

* swarm/storage: Remove validator prefix for metadata chunk

* swarm/storage/mru: Use Address instead of PublicKey

* swarm/storage/mru: Change index from name to metadata chunk addr

* swarm/storage/mru: Refactor swarm/api/... to MRU index changes

* swarm/storage/mru: Refactor cleanup

* swarm/storage/mru: Rebase cleanup

* swarm: Use constructor for GenericSigner MRU in swarm.go

* swarm/storage: Change to BMTHash for MRU hashing

* swarm/storage: Reduce loglevel on chunk validator logs

* swarm/storage/mru: Delint

* swarm: MRU Rebase cleanup

* swarm/storage/mru: client-side mru signatures

Rebase to PR #668 and fix all conflicts

* swarm/storage/mru:  refactor and documentation

* swarm/resource/mru: error-checking  tests for parseUpdate/newUpdateChunk

* swarm/storage/mru: Added resourcemetadata tests

* swarm/storage/mru: Added tests  for UpdateRequest

* swarm/storage/mru: more test coverage for UpdateRequest and comments

* swarm/storage/mru: Avoid fake chunks in parseUpdate()

* swarm/storage/mru: Documented resource.go extensively

moved some functions where they make most sense

* swarm/storage/mru: increase test coverage for UpdateRequest and

variable name changes throughout to increase consistency

* swarm/storage/mru: moved default timestamp to NewCreateRequest-

* swarm/storage/mru: lookup refactor

* swarm/storage/mru: added comments and renamed raw flag to rawmru

* swarm/storage/mru: fix receiver typo

* swarm/storage/mru: refactored update chunk new/create

* swarm/storage/mru:  refactored signature digest to avoid malleability

* swarm/storage/mru: optimize update data serialization

* swarm/storage/mru: refactor and cleanup

* swarm/storage/mru: add timestamp struct and serialization

* swarm/storage/mru: fix lint error and mark some old code for deletion

* swarm/storage/mru: remove unnecessary variable

* swarm/storage/mru: Added more comments throughout

* swarm/storage/mru: Refactored metadata chunk layout + extensive error...

* swarm/storage/mru: refactor cli parser
Changed resource info output to JSON

* swarm/storage/mru: refactor serialization for extensibility

refactored error messages to NewErrorf

* swarm/storage/mru: Moved Signature to resource_sign.
Check Sign errors in server tests

* swarm/storage/mru: Remove isSafeName() checks

* swarm/storage/mru: scrubbed off all references to "block" for time

* swarm/storage/mru: removed superfluous isSynced() call.

* swarm/storage/mru: remove isMultihash() and ToSafeName functions

* swarm/storage/mru: various fixes and comments

* swarm/storage/mru: decoupled cli for independent create/update
* Made resource name optional
* Removed unused LookupPrevious

* swarm/storage/mru: Decoupled resource create / update & refactor

* swarm/storage/mru: Fixed some comments as per issues raised in PR #743

* swarm/storage/mru: Cosmetic changes as per #743 comments

* swarm/storage/mru: refct request encoder/decoder > marshal/unmarshal

* swarm/storage/mru: Cosmetic changes as per review in #748

* swarm/storage/mru: removed timestamp proof placeholder

* swarm/storage/mru: cosmetic/doc/fixes changes as per comments in #704

* swarm/storage/mru: removed unnecessary check in Handler.update

* swarm/storage/mru: Implemented Marshaler/Unmarshaler iface in Request

* swarm/storage/mru: Fixed linter error

* swarm/storage/mru: removed redundant address in signature digest

* swarm/storage/mru: fixed bug: LookupLatestVersionInPeriod not working

* swarm/storage/mru: Unfold Request creation API for create or update+create
set common time source for mru package

* swarm/api/http: fix HandleGetResource error variable shadowed
when requesting a resource that does not exist

* swarm/storage/mru: Add simple check to detect duplicate updates

* swarm/storage/mru: moved Multihash() to the right place.

* cmd/swarm: remove unneeded clientaccountmanager.go

* swarm/storage/mru: Changed some comments as per reviews in #784

* swarm/storage/mru: Made SignedResourceUpdate.GetDigest() public

* swarm/storage/mru: cosmetic changes as per comments in #784

* cmd/swarm: Inverted --multihash flag default

* swarm/storage/mru: removed Verify from SignedResourceUpdate.fromChunk

* swarm/storage/mru: Moved validation code out of serializer
Cosmetic / comment changes

* swarm/storage/mru: Added unit tests for UpdateLookup

* swarm/storage/mru: Increased coverage of metadata serialization

* swarm/storage/mru: Increased test coverage of updateHeader serializers

* swarm/storage/mru: Add resourceUpdate serializer test

1 files changed, 88 insertions, 0 deletions

diff --git a/swarm/storage/mru/updateheader.go b/swarm/storage/mru/updateheader.go
new file mode 100644
index 000000000..3ac20c189
--- /dev/null
+++ b/swarm/storage/mru/updateheader.go
@@ -0,0 +1,88 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package mru
+
+import (
+	"github.com/ethereum/go-ethereum/swarm/storage"
+)
+
+// updateHeader models the non-payload components of a Resource Update
+type updateHeader struct {
+	UpdateLookup        // UpdateLookup contains the information required to locate this resource (components of the search key used to find it)
+	multihash    bool   // Whether the data in this Resource Update should be interpreted as multihash
+	metaHash     []byte // SHA3 hash of the metadata chunk (less ownerAddr). Used to prove ownerhsip of the resource.
+}
+
+const metaHashLength = storage.KeyLength
+
+// updateLookupLength bytes
+// 1 byte flags (multihash bool for now)
+// 32 bytes metaHash
+const updateHeaderLength = updateLookupLength + 1 + metaHashLength
+
+// binaryPut serializes the resource header information into the given slice
+func (h *updateHeader) binaryPut(serializedData []byte) error {
+	if len(serializedData) != updateHeaderLength {
+		return NewErrorf(ErrInvalidValue, "Incorrect slice size to serialize updateHeaderLength. Expected %d, got %d", updateHeaderLength, len(serializedData))
+	}
+	if len(h.metaHash) != metaHashLength {
+		return NewError(ErrInvalidValue, "updateHeader.binaryPut called without metaHash set")
+	}
+	if err := h.UpdateLookup.binaryPut(serializedData[:updateLookupLength]); err != nil {
+		return err
+	}
+	cursor := updateLookupLength
+	copy(serializedData[cursor:], h.metaHash[:metaHashLength])
+	cursor += metaHashLength
+
+	var flags byte
+	if h.multihash {
+		flags |= 0x01
+	}
+
+	serializedData[cursor] = flags
+	cursor++
+
+	return nil
+}
+
+// binaryLength returns the expected size of this structure when serialized
+func (h *updateHeader) binaryLength() int {
+	return updateHeaderLength
+}
+
+// binaryGet restores the current updateHeader instance from the information contained in the passed slice
+func (h *updateHeader) binaryGet(serializedData []byte) error {
+	if len(serializedData) != updateHeaderLength {
+		return NewErrorf(ErrInvalidValue, "Incorrect slice size to read updateHeaderLength. Expected %d, got %d", updateHeaderLength, len(serializedData))
+	}
+
+	if err := h.UpdateLookup.binaryGet(serializedData[:updateLookupLength]); err != nil {
+		return err
+	}
+	cursor := updateLookupLength
+	h.metaHash = make([]byte, metaHashLength)
+	copy(h.metaHash[:storage.KeyLength], serializedData[cursor:cursor+storage.KeyLength])
+	cursor += metaHashLength
+
+	flags := serializedData[cursor]
+	cursor++
+
+	h.multihash = flags&0x01 != 0
+
+	return nil
+}