Postgres

README.md

@@ -170,7 +170,5 @@ The service uses the following enironment variables:
 ## TODOs:
 
 * Fix the Stop method to hash the input instead of the output.
-* Fix more timing attacks.
-* Write a postgres storage backend.
 * Write errors messages as output.
 * Use the main key to encrypt the stored data (poll keys and poll hashes)

decrypt/decrypt.go

@@ -71,7 +71,7 @@ func (d *Decrypt) Start(ctx context.Context, pollID string) (pubKey []byte, pubK
 	}
 
 	// TODO: Load Key and CreatePoll Key have probably be atomic.
-	pollKey, err := d.store.LoadKey(pollID)
+	pollKey, err := d.store.LoadKey(ctx, pollID)
 	if err != nil {
 		if !errors.Is(err, errorcode.NotExist) {
 			return nil, nil, fmt.Errorf("loading poll key: %w", err)
@@ -83,7 +83,7 @@ func (d *Decrypt) Start(ctx context.Context, pollID string) (pubKey []byte, pubK
 		}
 
 		pollKey = key
-		if err := d.store.SaveKey(pollID, key); err != nil {
+		if err := d.store.SaveKey(ctx, pollID, key); err != nil {
 			return nil, nil, fmt.Errorf("saving poll key: %w", err)
 		}
 	}
@@ -107,7 +107,7 @@ func (d *Decrypt) Start(ctx context.Context, pollID string) (pubKey []byte, pubK
 //
 // TODO: This implementation is wrong. Not the output has to be hashed and saved, but the input.
 func (d *Decrypt) Stop(ctx context.Context, pollID string, voteList [][]byte) (decryptedContent, signature []byte, err error) {
-	pollKey, err := d.store.LoadKey(pollID)
+	pollKey, err := d.store.LoadKey(ctx, pollID)
 	if err != nil {
 		return nil, nil, fmt.Errorf("loading poll key: %w", err)
 	}
@@ -131,7 +131,7 @@ func (d *Decrypt) Stop(ctx context.Context, pollID string, voteList [][]byte) (d
 	// This has to be the last step of this function to protect agains timing
 	// attacks. All other steps have to be run, even when the calll is doomed to
 	// fail in this step
-	if err := d.store.ValidateSignature(pollID, signature); err != nil {
+	if err := d.store.ValidateSignature(ctx, pollID, signature); err != nil {
 		if errors.Is(err, errorcode.Invalid) {
 			return nil, nil, fmt.Errorf("stop was called with different parameters before")
 		}
@@ -143,7 +143,7 @@ func (d *Decrypt) Stop(ctx context.Context, pollID string, voteList [][]byte) (d
 
 // Clear stops a poll by removing the generated cryptographic key.
 func (d *Decrypt) Clear(ctx context.Context, pollID string) error {
-	if err := d.store.ClearPoll(pollID); err != nil {
+	if err := d.store.ClearPoll(ctx, pollID); err != nil {
 		return fmt.Errorf("clearing poll from store: %w", err)
 	}
 	return nil
@@ -261,12 +261,12 @@ type Store interface {
 	// SaveKey stores the private key.
 	//
 	// Has to return an error `errorcode.Exist` if the key is already known.
-	SaveKey(id string, key []byte) error
+	SaveKey(ctx context.Context, id string, key []byte) error
 
 	// LoadKey returns the private key from the store.
 	//
 	// If the poll is unknown return `errorcode.NotExist`
-	LoadKey(id string) (key []byte, err error)
+	LoadKey(ctx context.Context, id string) (key []byte, err error)
 
 	// ValidateSignature makes sure, that no other signature is saved for a
 	// poll. Saves the signature for future calls.
@@ -275,12 +275,12 @@ type Store interface {
 	// call.
 	//
 	// Has to return `errorcode.NotExist` when the id does not exist.
-	ValidateSignature(id string, hash []byte) error
+	ValidateSignature(ctx context.Context, id string, hash []byte) error
 
 	// ClearPoll removes all data for the poll.
 	//
 	// Does not return an error if poll does not exist.
-	ClearPoll(id string) error
+	ClearPoll(ctx context.Context, id string) error
 }
 
 // jsonListToContent creates one byte slice from a list of votes in json format.

decrypt/mock_test.go

@@ -2,6 +2,7 @@ package decrypt_test
 
 import (
 	"bytes"
+	"context"
 	"fmt"
 	"sync"
 
@@ -53,7 +54,7 @@ func NewStoreMock() *StoreMock {
 	}
 }
 
-func (s *StoreMock) SaveKey(id string, key []byte) error {
+func (s *StoreMock) SaveKey(_ context.Context, id string, key []byte) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
@@ -68,7 +69,7 @@ func (s *StoreMock) SaveKey(id string, key []byte) error {
 // LoadKey returns the private key from the store.
 //
 // If the poll is unknown return (nil, nil)
-func (s *StoreMock) LoadKey(id string) ([]byte, error) {
+func (s *StoreMock) LoadKey(_ context.Context, id string) ([]byte, error) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
@@ -83,7 +84,7 @@ func (s *StoreMock) LoadKey(id string) ([]byte, error) {
 // poll. Saves the signature for future calls.
 //
 // Has to return an error if the id is unknown in the store.
-func (s *StoreMock) ValidateSignature(id string, signature []byte) error {
+func (s *StoreMock) ValidateSignature(_ context.Context, id string, signature []byte) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
@@ -106,7 +107,7 @@ func (s *StoreMock) ValidateSignature(id string, signature []byte) error {
 }
 
 // Clear removes all data for the poll.
-func (s *StoreMock) ClearPoll(id string) error {
+func (s *StoreMock) ClearPoll(_ context.Context, id string) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 

go.mod

@@ -5,14 +5,46 @@ go 1.22
 require (
 	github.com/alecthomas/kong v0.9.0
 	github.com/golang/protobuf v1.5.4
+	github.com/jackc/pgx/v5 v5.6.0
+	github.com/ory/dockertest/v3 v3.10.0
 	golang.org/x/crypto v0.25.0
 	golang.org/x/sys v0.22.0
 	google.golang.org/grpc v1.65.0
 	google.golang.org/protobuf v1.34.2
 )
 
 require (
-	golang.org/x/net v0.25.0 // indirect
+	dario.cat/mergo v1.0.0 // indirect
+	github.com/Azure/go-ansiterm v0.0.0-20230124172434-306776ec8161 // indirect
+	github.com/Microsoft/go-winio v0.6.2 // indirect
+	github.com/Nvveen/Gotty v0.0.0-20120604004816-cd527374f1e5 // indirect
+	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
+	github.com/containerd/continuity v0.4.3 // indirect
+	github.com/docker/cli v27.0.3+incompatible // indirect
+	github.com/docker/docker v27.0.3+incompatible // indirect
+	github.com/docker/go-connections v0.5.0 // indirect
+	github.com/docker/go-units v0.5.0 // indirect
+	github.com/go-viper/mapstructure/v2 v2.0.0 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
+	github.com/jackc/puddle/v2 v2.2.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/moby/docker-image-spec v1.3.1 // indirect
+	github.com/moby/term v0.5.0 // indirect
+	github.com/opencontainers/go-digest v1.0.0 // indirect
+	github.com/opencontainers/image-spec v1.1.0 // indirect
+	github.com/opencontainers/runc v1.1.13 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/rogpeppe/go-internal v1.12.0 // indirect
+	github.com/sirupsen/logrus v1.9.3 // indirect
+	github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb // indirect
+	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
+	github.com/xeipuuv/gojsonschema v1.2.0 // indirect
+	golang.org/x/net v0.27.0 // indirect
+	golang.org/x/sync v0.7.0 // indirect
 	golang.org/x/text v0.16.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20240528184218-531527333157 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
 )