path: root/swarm/storage/feeds/request_test.go

// 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 feeds

import (
    "bytes"
    "encoding/binary"
    "encoding/json"
    "fmt"
    "reflect"
    "testing"

    "github.com/ethereum/go-ethereum/crypto"
    "github.com/ethereum/go-ethereum/swarm/storage"
    "github.com/ethereum/go-ethereum/swarm/storage/feeds/lookup"
)

func areEqualJSON(s1, s2 string) (bool, error) {
    //credit for the trick: turtlemonvh https://gist.github.com/turtlemonvh/e4f7404e28387fadb8ad275a99596f67
    var o1 interface{}
    var o2 interface{}

    err := json.Unmarshal([]byte(s1), &o1)
    if err != nil {
        return false, fmt.Errorf("Error mashalling string 1 :: %s", err.Error())
    }
    err = json.Unmarshal([]byte(s2), &o2)
    if err != nil {
        return false, fmt.Errorf("Error mashalling string 2 :: %s", err.Error())
    }

    return reflect.DeepEqual(o1, o2), nil
}

// TestEncodingDecodingUpdateRequests ensures that requests are serialized properly
// while also checking cryptographically that only the owner of a feed can update it.
func TestEncodingDecodingUpdateRequests(t *testing.T) {

    charlie := newCharlieSigner() //Charlie
    bob := newBobSigner()         //Bob

    // Create a feed to our good guy Charlie's name
    topic, _ := NewTopic("a good topic name", nil)
    firstRequest := NewFirstRequest(topic)
    firstRequest.User = charlie.Address()

    // We now encode the create message to simulate we send it over the wire
    messageRawData, err := firstRequest.MarshalJSON()
    if err != nil {
        t.Fatalf("Error encoding first feed update request: %s", err)
    }

    // ... the message arrives and is decoded...
    var recoveredFirstRequest Request
    if err := recoveredFirstRequest.UnmarshalJSON(messageRawData); err != nil {
        t.Fatalf("Error decoding first feed update request: %s", err)
    }

    // ... but verification should fail because it is not signed!
    if err := recoveredFirstRequest.Verify(); err == nil {
        t.Fatal("Expected Verify to fail since the message is not signed")
    }

    // We now assume that the feed ypdate was created and propagated.

    const expectedSignature = "0x7235b27a68372ddebcf78eba48543fa460864b0b0e99cb533fcd3664820e603312d29426dd00fb39628f5299480a69bf6e462838d78de49ce0704c754c9deb2601"
    const expectedJSON = `{"feed":{"topic":"0x6120676f6f6420746f706963206e616d65000000000000000000000000000000","user":"0x876a8936a7cd0b79ef0735ad0896c1afe278781c"},"epoch":{"time":1000,"level":1},"protocolVersion":0,"data":"0x5468697320686f75722773207570646174653a20537761726d2039392e3020686173206265656e2072656c656173656421"}`

    //Put together an unsigned update request that we will serialize to send it to the signer.
    data := []byte("This hour's update: Swarm 99.0 has been released!")
    request := &Request{
        Update: Update{
            ID: ID{
                Epoch: lookup.Epoch{
                    Time:  1000,
                    Level: 1,
                },
                Feed: firstRequest.Update.Feed,
            },
            data: data,
        },
    }

    messageRawData, err = request.MarshalJSON()
    if err != nil {
        t.Fatalf("Error encoding update request: %s", err)
    }

    equalJSON, err := areEqualJSON(string(messageRawData), expectedJSON)
    if err != nil {
        t.Fatalf("Error decoding update request JSON: %s", err)
    }
    if !equalJSON {
        t.Fatalf("Received a different JSON message. Expected %s, got %s", expectedJSON, string(messageRawData))
    }

    // now the encoded message messageRawData is sent over the wire and arrives to the signer

    //Attempt to extract an UpdateRequest out of the encoded message
    var recoveredRequest Request
    if err := recoveredRequest.UnmarshalJSON(messageRawData); err != nil {
        t.Fatalf("Error decoding update request: %s", err)
    }

    //sign the request and see if it matches our predefined signature above.
    if err := recoveredRequest.Sign(charlie); err != nil {
        t.Fatalf("Error signing request: %s", err)
    }

    compareByteSliceToExpectedHex(t, "signature", recoveredRequest.Signature[:], expectedSignature)

    // mess with the signature and see what happens. To alter the signature, we briefly decode it as JSON
    // to alter the signature field.
    var j updateRequestJSON
    if err := json.Unmarshal([]byte(expectedJSON), &j); err != nil {
        t.Fatal("Error unmarshalling test json, check expectedJSON constant")
    }
    j.Signature = "Certainly not a signature"
    corruptMessage, _ := json.Marshal(j) // encode the message with the bad signature
    var corruptRequest Request
    if err = corruptRequest.UnmarshalJSON(corruptMessage); err == nil {
        t.Fatal("Expected DecodeUpdateRequest to fail when trying to interpret a corrupt message with an invalid signature")
    }

    // Now imagine Bob wants to create an update of his own about the same feed,
    // signing a message with his private key
    if err := request.Sign(bob); err != nil {
        t.Fatalf("Error signing: %s", err)
    }

    // Now Bob encodes the message to send it over the wire...
    messageRawData, err = request.MarshalJSON()
    if err != nil {
        t.Fatalf("Error encoding message:%s", err)
    }

    // ... the message arrives to our Swarm node and it is decoded.
    recoveredRequest = Request{}
    if err := recoveredRequest.UnmarshalJSON(messageRawData); err != nil {
        t.Fatalf("Error decoding message:%s", err)
    }

    // Before checking what happened with Bob's update, let's see what would happen if we mess
    // with the signature big time to see if Verify catches it
    savedSignature := *recoveredRequest.Signature                               // save the signature for later
    binary.LittleEndian.PutUint64(recoveredRequest.Signature[5:], 556845463424) // write some random data to break the signature
    if err = recoveredRequest.Verify(); err == nil {
        t.Fatal("Expected Verify to fail on corrupt signature")
    }

    // restore the Bob's signature from corruption
    *recoveredRequest.Signature = savedSignature

    // Now the signature is not corrupt
    if err = recoveredRequest.Verify(); err != nil {
        t.Fatal(err)
    }

    // Reuse object and sign with our friend Charlie's private key
    if err := recoveredRequest.Sign(charlie); err != nil {
        t.Fatalf("Error signing with the correct private key: %s", err)
    }

    // And now, Verify should work since this update now belongs to Charlie
    if err = recoveredRequest.Verify(); err != nil {
        t.Fatalf("Error verifying that Charlie, can sign a reused request object:%s", err)
    }

    // mess with the lookup key to make sure Verify fails:
    recoveredRequest.Time = 77999 // this will alter the lookup key
    if err = recoveredRequest.Verify(); err == nil {
        t.Fatalf("Expected Verify to fail since the lookup key has been altered")
    }
}

func getTestRequest() *Request {
    return &Request{
        Update: *getTestFeedUpdate(),
    }
}

func TestUpdateChunkSerializationErrorChecking(t *testing.T) {

    // Test that parseUpdate fails if the chunk is too small
    var r Request
    if err := r.fromChunk(storage.ZeroAddr, make([]byte, minimumUpdateDataLength-1+signatureLength)); err == nil {
        t.Fatalf("Expected request.fromChunk to fail when chunkData contains less than %d bytes", minimumUpdateDataLength)
    }

    r = *getTestRequest()

    _, err := r.toChunk()
    if err == nil {
        t.Fatal("Expected request.toChunk to fail when there is no data")
    }
    r.data = []byte("Al bien hacer jamás le falta premio") // put some arbitrary length data
    _, err = r.toChunk()
    if err == nil {
        t.Fatal("expected request.toChunk to fail when there is no signature")
    }

    charlie := newCharlieSigner()
    if err := r.Sign(charlie); err != nil {
        t.Fatalf("error signing:%s", err)
    }

    chunk, err := r.toChunk()
    if err != nil {
        t.Fatalf("error creating update chunk:%s", err)
    }

    compareByteSliceToExpectedHex(t, "chunk", chunk.Data(), "0x0000000000000000776f726c64206e657773207265706f72742c20657665727920686f7572000000876a8936a7cd0b79ef0735ad0896c1afe278781ce803000000000019416c206269656e206861636572206a616dc3a173206c652066616c7461207072656d696f5a0ffe0bc27f207cd5b00944c8b9cee93e08b89b5ada777f123ac535189333f174a6a4ca2f43a92c4a477a49d774813c36ce8288552c58e6205b0ac35d0507eb00")

    var recovered Request
    recovered.fromChunk(chunk.Address(), chunk.Data())
    if !reflect.DeepEqual(recovered, r) {
        t.Fatal("Expected recovered feed update request to equal the original one")
    }
}

// check that signature address matches update signer address
func TestReverse(t *testing.T) {

    epoch := lookup.Epoch{
        Time:  7888,
        Level: 6,
    }

    // make fake timeProvider
    timeProvider := &fakeTimeProvider{
        currentTime: startTime.Time,
    }

    // signer containing private key
    signer := newAliceSigner()

    // set up rpc and create feeds handler
    _, _, teardownTest, err := setupTest(timeProvider, signer)
    if err != nil {
        t.Fatal(err)
    }
    defer teardownTest()

    topic, _ := NewTopic("Cervantes quotes", nil)
    feed := Feed{
        Topic: topic,
        User:  signer.Address(),
    }

    data := []byte("Donde una puerta se cierra, otra se abre")

    request := new(Request)
    request.Feed = feed
    request.Epoch = epoch
    request.data = data

    // generate a chunk key for this request
    key := request.Addr()

    if err = request.Sign(signer); err != nil {
        t.Fatal(err)
    }

    chunk, err := request.toChunk()
    if err != nil {
        t.Fatal(err)
    }

    // check that we can recover the owner account from the update chunk's signature
    var checkUpdate Request
    if err := checkUpdate.fromChunk(chunk.Address(), chunk.Data()); err != nil {
        t.Fatal(err)
    }
    checkdigest, err := checkUpdate.GetDigest()
    if err != nil {
        t.Fatal(err)
    }
    recoveredAddr, err := getUserAddr(checkdigest, *checkUpdate.Signature)
    if err != nil {
        t.Fatalf("Retrieve address from signature fail: %v", err)
    }
    originalAddr := crypto.PubkeyToAddress(signer.PrivKey.PublicKey)

    // check that the metadata retrieved from the chunk matches what we gave it
    if recoveredAddr != originalAddr {
        t.Fatalf("addresses dont match: %x != %x", originalAddr, recoveredAddr)
    }

    if !bytes.Equal(key[:], chunk.Address()[:]) {
        t.Fatalf("Expected chunk key '%x', was '%x'", key, chunk.Address())
    }
    if epoch != checkUpdate.Epoch {
        t.Fatalf("Expected epoch to be '%s', was '%s'", epoch.String(), checkUpdate.Epoch.String())
    }
    if !bytes.Equal(data, checkUpdate.data) {
        t.Fatalf("Expected data '%x', was '%x'", data, checkUpdate.data)
    }
}