.

.vscode/launch.json

@@ -4,14 +4,14 @@
     // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
     "version": "0.2.0",
     "configurations": [
-
         {
             "name": "Launch API",
             "type": "go",
             "request": "launch",
             "mode": "auto",
             "program": "${workspaceFolder}/cmd/api",
-            "envFile": "${workspaceFolder}/.env"
+            "envFile": "${workspaceFolder}/.env",
+            "args": ["--env=development"]
         }
     ]
 }

cmd/api/helpers.go

@@ -11,7 +11,10 @@ import (
 	"strconv"
 	"party.at/party/internal/validator"
 	"github.com/julienschmidt/httprouter"
-	
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"crypto/rand"
 )
 
 type envelope map[string]interface{}
@@ -191,3 +194,19 @@ func (app *application) background(fn func()) {
 		fn()
 	}()
 }
+
+func GenerateIssueKey() ([]byte, int, []byte, error) {
+	key, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		return nil, 0, nil, err
+	}
+
+	// Encode private key as PEM
+	privDER := x509.MarshalPKCS1PrivateKey(key)
+	privPEM := pem.EncodeToMemory(&pem.Block{
+		Type:  "RSA PRIVATE KEY",
+		Bytes: privDER,
+	})
+
+	return key.N.Bytes(), key.E, privPEM, err
+}

cmd/api/helpers_test.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"strconv"
+	"testing"
+
+	"github.com/julienschmidt/httprouter"
+)
+
+func TestReadIDParam(t *testing.T) {
+	app := newTestApplication(t)
+
+	const test_id int64 = 3
+
+	r := httptest.NewRequest(http.MethodGet, "/v1/issues/" + strconv.FormatInt(test_id, 10), nil)
+
+	params := httprouter.Params{{Key: "id", Value: "3"}}
+	ctx := context.WithValue(r.Context(), httprouter.ParamsKey, params)
+	r = r.WithContext(ctx)
+
+	id, err := app.readIDParam(r)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if id != test_id {
+		t.Errorf("want %d, got id %d", test_id, id)
+	}
+}

cmd/api/issues.go

@@ -12,35 +12,30 @@ import (
 	"errors"
 	"party.at/party/internal/data"
 	"party.at/party/internal/validator"
+	"encoding/hex"
 )
 
 func (app *application) listIssuesHandler(w http.ResponseWriter, r *http.Request) {
-	// To keep things consistent with our other handlers, we'll define an input struct
-	// to hold the expected values from the request query string.
+
 	var input struct {
 		Title string
 		data.Filters
 	}
 
-	// Initialize a new Validator instance.
+
 	v := validator.New()
-	// Call r.URL.Query() to get the url.Values map containing the query string data.
+
 	qs := r.URL.Query()
 
-	// Use our helpers to extract the title and genres query string values, falling back
-	// to defaults of an empty string and an empty slice respectively if they are not
-	// provided by the client.
+
 	input.Title = app.readString(qs, "title", "")
 	// input.Genres = app.readCSV(qs, "genres", []string{})
 
-	// Get the page and page_size query string values as integers. Notice that we set
-	// the default page value to 1 and default page_size to 20, and that we pass the
-	// validator instance as the final argument here.
+
 	input.Filters.Page = app.readInt(qs, "page", 1, v)
 	input.Filters.PageSize = app.readInt(qs, "page_size", 20, v)
 
-	// Extract the sort query string value, falling back to "id" if it is not provided
-	// by the client (which will imply a ascending sort on issue ID).
+
 	input.Filters.Sort = app.readString(qs, "sort", "id")
 	input.Filters.SortSafelist = []string{"id", "-id", "title", "-title", "description", "-description"}
 
@@ -77,11 +72,20 @@ func (app *application) createIssueHandler(w http.ResponseWriter, r *http.Reques
 		return
 	}
 
+	n, e, private_pem, err := GenerateIssueKey()
+	if err != nil {
+		app.serverErrorResponse(w, r, err)
+		return
+	}
+
 	issue := &data.Issue{
 		Title: input.Title,
 		Description: input.Description,
 		StartTime: input.StartTime,
 		EndTime: input.EndTime,
+		N: n,
+		E: e,
+		PrivatePem: private_pem,
 	}
 
 	v := validator.New()
@@ -219,3 +223,73 @@ func (app *application) deleteIssueHandler(w http.ResponseWriter, r *http.Reques
 		app.serverErrorResponse(w, r, err)
 	}
 }
+
+func (app *application) readIssuePubKeyHandler(w http.ResponseWriter, r *http.Request) {
+	id, err := app.readIDParam(r)
+	if err != nil {
+		app.notFoundResponse(w, r)
+		return
+	}
+
+	issue, err := app.models.Issues.Get(id)
+	if err != nil {
+		switch {
+		case errors.Is(err, data.ErrRecordNotFound):
+			app.notFoundResponse(w, r)
+		default:
+			app.serverErrorResponse(w, r, err)
+		}
+		return
+	}
+
+	type response struct {
+		N string `json:"n"`
+		E int    `json:"e"`
+	}
+
+	res := response{
+		N: hex.EncodeToString(issue.N),
+		E: issue.E,
+	}
+
+
+	err = app.writeJSON(w, http.StatusOK, envelope{"public_key": res}, nil)
+	if err != nil {
+		app.serverErrorResponse(w, r, err)
+	}
+}
+
+func (app *application) blindSignIssueVoteHandler(w http.ResponseWriter, r *http.Request) {
+	id, err := app.readIDParam(r)
+	if err != nil {
+		app.notFoundResponse(w, r)
+		return
+	}
+
+	issue, err := app.models.Issues.Get(id)
+	if err != nil {
+		switch {
+		case errors.Is(err, data.ErrRecordNotFound):
+			app.notFoundResponse(w, r)
+		default:
+			app.serverErrorResponse(w, r, err)
+		}
+		return
+	}
+
+	type response struct {
+		N string `json:"n"`
+		E int    `json:"e"`
+	}
+
+	res := response{
+		N: hex.EncodeToString(issue.N),
+		E: issue.E,
+	}
+
+
+	err = app.writeJSON(w, http.StatusOK, envelope{"public_key": res}, nil)
+	if err != nil {
+		app.serverErrorResponse(w, r, err)
+	}
+}

cmd/api/issues_test.go

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"strconv"
+	"testing"
+	"time"
+)
+
+func TestReadIssueHandler(t *testing.T) {
+	app := newTestApplication(t)
+	ts := newTestServer(t, app, app.routes())
+	defer ts.Close()
+
+	token := ts.registerAndLogin(t, uniqueEmail(), "pa$$word123")
+
+	req := map[string]any{
+		"title":       "An old silent pond...",
+		"description": "A frog jumps into the pond",
+		"start_time":  time.Now().Format(time.RFC3339),
+		"end_time":    time.Now().Add(24 * time.Hour).Format(time.RFC3339),
+	}
+
+	code, _, res := ts.postJSONWithToken(t, "/v1/issues", token, req)
+	if code != http.StatusCreated {
+        t.Fatalf("seed issue: want 201 got %d: %s", code, res)
+    }
+
+	var resp struct {
+        Issue struct {
+            ID int64 `json:"id"`
+        } `json:"issue"`
+    }
+    json.Unmarshal(res, &resp)
+    issueID := resp.Issue.ID
+
+	tests := []struct {
+		name string
+		urlPath string
+		wantCode int
+		wantBody []byte
+	}{
+		{"Valid ID",        "/v1/issues/" + strconv.Itoa(int(issueID)), http.StatusOK, []byte("An old silent pond...")},
+		{"Non-existent ID", "/v1/issues/" + strconv.Itoa(int(issueID + 1)), http.StatusNotFound, nil},
+		{"Negative ID",     "/v1/issues/-1", http.StatusNotFound, nil},
+		{"Decimal ID",      "/v1/issues/1.23", http.StatusNotFound, nil},
+		{"String ID",       "/v1/issues/foo", http.StatusNotFound, nil},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			code, _, body := ts.getWithToken(t, tt.urlPath, token)
+
+			if code != tt.wantCode {
+				t.Errorf("want %d; got %d", tt.wantCode, code)
+			}
+
+			if !bytes.Contains(body, tt.wantBody) {
+				t.Errorf("want body to contain %q; got %q", tt.wantBody, string(body))
+			}
+		})
+	}
+}

cmd/api/main.go

@@ -24,6 +24,10 @@ import (
 	"party.at/party/internal/data"
 	"party.at/party/internal/mailer"
 	"party.at/party/internal/jsonlog"
+
+	"crypto/rand"
+	"crypto/aes"
+	"crypto/cipher"
 )
 
 var version string
@@ -80,12 +84,31 @@ var upgrader = websocket.Upgrader{
 
 func main() {
 
-	fmt.Printf("Full Args: %v\n", os.Args)
+	// 32 bytes = AES-256
+	var key [32]byte
+	if _, err := rand.Read(key[:]); err != nil {
+		panic(err)
+	}
+
+	message := []byte("hello secure world")
+
+	nonce, ciphertext, err := encrypt(key, message)
+	if err != nil {
+		panic(err)
+	}
+
+	plaintext, err := decrypt(key, nonce, ciphertext)
+	if err != nil {
+		panic(err)
+	}
+
+	fmt.Printf("Original: %s\n", message)
+	fmt.Printf("Decrypted: %s\n", plaintext)
 
 	var cfg config
 
 	flag.IntVar(&cfg.port, "port", 4000, "API server port")
-	flag.StringVar(&cfg.env, "env", "development", "Environment (development|staging|production)")
+	flag.StringVar(&cfg.env, "env", "production", "Environment (development|staging|production)")
 	flag.StringVar(&cfg.db.dsn, "db-dsn", os.Getenv("PARTY_DB_DSN"), "PostgreSQL DSN")
 	//addr := flag.String("addr", ":8443", "HTTP network address")
 
@@ -97,7 +120,7 @@ func main() {
 	flag.IntVar(&cfg.smtp.port, "smtp-port", 25, "SMTP port")
 	flag.StringVar(&cfg.smtp.username, "smtp-username", "98cf60028d7fcb", "SMTP username")
 	flag.StringVar(&cfg.smtp.password, "smtp-password", "b9d4a35372e971", "SMTP password")
-	flag.StringVar(&cfg.smtp.sender, "smtp-sender", "Greenlight <no-reply@greenlight.alexedwards.net>", "SMTP sender")
+	flag.StringVar(&cfg.smtp.sender, "smtp-sender", "DPÖ <no-reply@party.at>", "SMTP sender")
 
 	flag.Float64Var(&cfg.limiter.rps, "limiter-rps", 2, "Rate limiter maximum requests per second")
 	flag.IntVar(&cfg.limiter.burst, "limiter-burst", 4, "Rate limiter maximum burst")
@@ -126,7 +149,6 @@ func main() {
 	if err != nil {
 		logger.PrintFatal(err, nil)
 	}
-	
 	defer db.Close()
 
 	expvar.NewString("version").Set(version)
@@ -188,3 +210,43 @@ func openDB(cfg config) (*sql.DB, error) {
 
 	return db, nil
 }
+
+func encrypt(key [32]byte, plaintext []byte) (nonce, ciphertext []byte, err error) {
+	block, err := aes.NewCipher(key[:])
+	if err != nil {
+		return nil, nil, err
+	}
+
+	aead, err := cipher.NewGCM(block)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	nonce = make([]byte, aead.NonceSize())
+	if _, err := rand.Read(nonce); err != nil {
+		panic(err)
+	}
+	
+
+	ciphertext = aead.Seal(nil, nonce, plaintext, nil)
+	return nonce, ciphertext, nil
+}
+
+func decrypt(key [32]byte, nonce, ciphertext []byte) ([]byte, error) {
+	block, err := aes.NewCipher(key[:])
+	if err != nil {
+		return nil, err
+	}
+
+	aead, err := cipher.NewGCM(block)
+	if err != nil {
+		return nil, err
+	}
+
+	plaintext, err := aead.Open(nil, nonce, ciphertext, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	return plaintext, nil
+}

cmd/api/middleware.go

@@ -64,7 +64,7 @@ func (app *application) rateLimit(next http.Handler) http.Handler {
 			// Loop through all clients. If they haven't been seen within the last three
 			// minutes, delete the corresponding entry from the map.
 			for ip, client := range clients {
-				if time.Since(client.lastSeen) > 3*time.Minute {
+				if time.Since(client.lastSeen) > 3 * time.Minute {
 					delete(clients, ip)
 				}
 			}

cmd/api/routes.go

@@ -27,15 +27,18 @@ func (app *application) routes() http.Handler {
 	router.HandlerFunc(http.MethodPatch,  "/v1/issues/:id", app.requirePermission("issues:write", app.updateIssueHandler))
 	router.HandlerFunc(http.MethodDelete, "/v1/issues/:id", app.requirePermission("issues:write", app.deleteIssueHandler))
 
-	router.HandlerFunc(http.MethodPost,  "/v1/users",     app.createUserHandler)
+	router.HandlerFunc(http.MethodGet,    "/v1/issues/:id/pubkey", app.requirePermission("issues:read", app.readIssuePubKeyHandler))
+	router.HandlerFunc(http.MethodPost,   "/v1/issues/:id/blind-sign", app.requirePermission("issues:read", app.blindSignIssueVoteHandler))
+
+	router.HandlerFunc(http.MethodPost,   "/v1/users",     app.createUserHandler)
 	// router.HandlerFunc(http.MethodGet,   "/v1/users/:id", app.readUserHandler)
 	// router.HandlerFunc(http.MethodPatch, "/v1/users/:id", app.updateUserHandler)
-	router.HandlerFunc(http.MethodDelete,  "/v1/users/:id", app.deleteUserHandler)
-	router.HandlerFunc(http.MethodPut, "/v1/users/activated", app.activateUserHandler)
+	router.HandlerFunc(http.MethodDelete, "/v1/users/:id", app.deleteUserHandler)
+	router.HandlerFunc(http.MethodPut,    "/v1/users/activated", app.activateUserHandler)
 
-	router.HandlerFunc(http.MethodPost, "/v1/tokens/authentication", app.createAuthenticationTokenHandler)
+	router.HandlerFunc(http.MethodPost,   "/v1/tokens/authentication", app.createAuthenticationTokenHandler)
 
-	router.Handler(http.MethodGet, "/debug/vars", expvar.Handler())
+	router.Handler    (http.MethodGet, "/debug/vars", expvar.Handler())
 
 	return app.metrics(app.recoverPanic(app.enableCORS(app.rateLimit(app.authenticate(router)))))
 }

cmd/api/testutils_test.go

@@ -0,0 +1,202 @@
+package main
+
+import (
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"os"
+	"encoding/json"
+	"bytes"
+	"fmt"
+	"time"
+
+	"party.at/party/internal/data"
+	"party.at/party/internal/jsonlog"
+)
+
+func newTestApplication(t *testing.T) *application {
+    cfg := config{}
+    cfg.db.dsn         = "postgres://party:password@localhost:5432/party?sslmode=disable"
+    cfg.db.maxOpenConns = 25
+    cfg.db.maxIdleConns = 25
+    cfg.db.maxIdleTime  = "15m"
+    cfg.limiter.enabled = false
+	cfg.env = "development"
+
+	logger := jsonlog.New(os.Stdout, jsonlog.LevelInfo)
+
+	db, err := openDB(cfg)
+	if err != nil {
+		logger.PrintFatal(err, nil)
+	}
+	t.Cleanup(func() {db.Close()})
+
+	return &application{
+		logger: logger,
+		models: data.NewModels(db),
+		config: cfg,
+	}
+}
+
+type testServer struct {
+	*httptest.Server
+	app *application
+}
+
+func newTestServer(t *testing.T, app *application, h http.Handler) *testServer {
+	ts := httptest.NewTLSServer(h)
+	return &testServer{ts, app}
+}
+
+func (ts *testServer) postJSON(t *testing.T, path string, body any) (int, http.Header, []byte) {
+    t.Helper()
+
+    b, err := json.Marshal(body)
+    if err != nil {
+        t.Fatal(err)
+    }
+
+    req, err := http.NewRequest(http.MethodPost, ts.URL+path, bytes.NewReader(b))
+    if err != nil {
+        t.Fatal(err)
+    }
+    req.Header.Set("Content-Type", "application/json")
+
+    resp, err := ts.Client().Do(req)
+    if err != nil {
+        t.Fatal(err)
+    }
+    defer resp.Body.Close()
+
+    respBody, err := io.ReadAll(resp.Body)
+    if err != nil {
+        t.Fatal(err)
+    }
+
+    return resp.StatusCode, resp.Header, respBody
+}
+
+func (ts *testServer) get(t *testing.T, path string) (int, http.Header, []byte) {
+	t.Helper()
+
+	rs, err := ts.Client().Get(ts.URL + path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer rs.Body.Close()
+	body, err := io.ReadAll(rs.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	return rs.StatusCode, rs.Header, body
+}
+
+// registers a user, activates them, logs in, returns the bearer token
+func (ts *testServer) registerAndLogin(t *testing.T, email, password string) string {
+    t.Helper()
+
+    // 1. Register
+    registerBody := map[string]any{
+		"email": email,
+		"password": password,
+		"username": email,
+		"name": "Test User",
+		"alt_name" : "",
+		"provider_id": 1,
+	}
+
+    code, _, body := ts.postJSON(t, "/v1/users", registerBody)
+    if code != http.StatusCreated {
+        t.Fatalf("register: want 201 got %d: %s", code, body)
+    }
+
+    // 2. Activate — if your flow requires it, either hit the endpoint
+    //    or directly flip the activated flag in the test DB
+    // ts.activateUser(t, email)
+
+    // 3. Login
+    loginBody := map[string]string{"email": email, "password": password}
+    code, _, body = ts.postJSON(t, "/v1/tokens/authentication", loginBody)
+    if code != http.StatusCreated {
+        t.Fatalf("login: want 201 got %d: %s", code, body)
+    }
+
+    // 4. Parse token out of response
+    var resp struct {
+        AuthenticationToken struct {
+            Token string `json:"token"`
+        } `json:"authentication_token"`
+    }
+    if err := json.Unmarshal(body, &resp); err != nil {
+        t.Fatalf("parse token: %v", err)
+    }
+    return resp.AuthenticationToken.Token
+}
+
+// activateUser directly updates the DB — avoids needing a real email flow
+// func (ts *testServer) activateUser(t *testing.T, email string) {
+//     t.Helper()
+//     _, err := ts.app.db.Exec("UPDATE users SET activated = true WHERE email = $1", email)
+//     if err != nil {
+//         t.Fatalf("activate user: %v", err)
+//     }
+// }
+
+// like ts.get but adds Authorization header
+func (ts *testServer) getWithToken(t *testing.T, path, token string) (int, http.Header, []byte) {
+    t.Helper()
+    req, err := http.NewRequest(http.MethodGet, ts.URL+path, nil)
+    if err != nil {
+        t.Fatal(err)
+    }
+    req.Header.Set("Authorization", "Bearer "+token)
+
+	rs, err := ts.Client().Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer rs.Body.Close()
+	body, err := io.ReadAll(rs.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	return rs.StatusCode, rs.Header, body
+}
+
+func (ts *testServer) postJSONWithToken(t *testing.T, path, token string, body any) (int, http.Header, []byte) {
+    t.Helper()
+
+	b, err := json.Marshal(body)
+    if err != nil {
+        t.Fatal(err)
+    }
+
+    req, err := http.NewRequest(http.MethodPost, ts.URL+path, bytes.NewReader(b))
+    if err != nil {
+        t.Fatal(err)
+    }
+	req.Header.Set("Content-Type", "application/json")
+    req.Header.Set("Authorization", "Bearer "+token)
+
+	rs, err := ts.Client().Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer rs.Body.Close()
+	respBody, err := io.ReadAll(rs.Body)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	return rs.StatusCode, rs.Header, respBody
+}
+
+func uniqueEmail() string {
+    return fmt.Sprintf("test_%d@example.com", time.Now().UnixNano())
+}

cmd/api/users.go

@@ -5,23 +5,22 @@ import (
 	"net/http"
 	"party.at/party/internal/data"
 	"party.at/party/internal/validator"
-	"database/sql"
 	"time"
 )
 
 func (app *application) createUserHandler(w http.ResponseWriter, r *http.Request) {
 
 	var input struct {
-		ProviderId  int64  `json:"provider_id"`
-		Username    string `json:"username"`
-		PhoneNumber string `json:"phone_number"`
-		Country     string `json:"country"`
-		Email       string `json:"email"`
-		Password    string `json:"password"`
-		Name        string `json:"name"`
-		AltName     string `json:"alt_name"`
+		ProviderId  int64     `json:"provider_id"`
+		Username    string    `json:"username"`
+		PhoneNumber string    `json:"phone_number"`
+		Country     string    `json:"country"`
+		Email       string    `json:"email"`
+		Password    string    `json:"password"`
+		Name        string    `json:"name"`
+		AltName     *string   `json:"alt_name"`
 		DateOfBirth time.Time `json:"date_of_birth"`
-		Address     string `json:"address"`
+		Address     string    `json:"address"`
 	}
 
 	err := app.readJSON(w, r, &input)
@@ -35,12 +34,16 @@ func (app *application) createUserHandler(w http.ResponseWriter, r *http.Request
 		PhoneNumber: input.PhoneNumber,
 		Country: input.Country,
 		Name: input.Name,
-		AltName: sql.NullString{String: input.AltName, Valid: true},
+		AltName: input.AltName,
 		DateOfBirth: input.DateOfBirth,
 		Address: input.Address,
 		Activated: false,
 	}
 
+	if app.config.env == "development" {
+		user.Activated = true
+	}
+
 	userIdentity := &data.UserIdentity{
 		ProviderID: input.ProviderId,
 		ProviderUserID: input.Username,
@@ -85,27 +88,43 @@ func (app *application) createUserHandler(w http.ResponseWriter, r *http.Request
 		return
 	}
 
-	token, err := app.models.Tokens.New(user.ID, userIdentity.ID, 3 * 24 * time.Hour, data.ScopeActivation)
+	if app.config.env == "development" {
+		err = app.models.Permissions.AddForUser(user.ID, "issues:write")
+		if err != nil {
+			app.serverErrorResponse(w, r, err)
+			return
+		}
+	}
+
+	if app.config.env == "production" {
+		token, err := app.models.Tokens.New(user.ID, userIdentity.ID, 3 * 24 * time.Hour, data.ScopeActivation)
+		if err != nil {
+			app.serverErrorResponse(w, r, err)
+			return
+		}
+
+		app.background(func() {
+			data := map[string]interface{}{
+				"token": token.Plaintext,
+				"userID": user.ID,
+			}
+
+			err = app.mailer.Send(user.Email, "user_welcome.tmpl", data)
+			if err != nil {
+				app.logger.PrintError(err, nil)
+			}
+		})
+	}
+
+	authentication_token, err := app.models.Tokens.New(user.ID, userIdentity.ID, 24 * time.Hour, data.ScopeAuthentication)
 	if err != nil {
 		app.serverErrorResponse(w, r, err)
 		return
 	}
 
-	app.background(func() {
-		data := map[string]interface{}{
-			"token": token.Plaintext,
-			"userID": user.ID,
-		}
-
-		err = app.mailer.Send(user.Email, "user_welcome.tmpl", data)
-		if err != nil {
-			app.logger.PrintError(err, nil)
-		}
-	})
-
 	// Write a JSON response containing the user data along with a 201 Created status
 	// code.
-	err = app.writeJSON(w, http.StatusCreated, envelope{"user": user}, nil)
+	err = app.writeJSON(w, http.StatusCreated, envelope{"user": user, "authentication_token": authentication_token}, nil)
 	if err != nil {
 		app.serverErrorResponse(w, r, err)
 	}

internal/data/blind_sign_requests.go

@@ -0,0 +1,88 @@
+package data
+
+import (
+	"time"
+	"database/sql"
+	"encoding/pem"
+	"context"
+	"errors"
+	"fmt"
+	"math/big"
+	"crypto/rsa"
+	"crypto/x509"
+)
+
+type BlindSignRequest struct {
+	UserID int64 `json:"user_id"`
+	IssueID int64 `json:"issue_id"`
+	Created time.Time `json:"created"`
+}
+
+type BlindSignRequestModel struct {
+	DB *sql.DB
+}
+
+func (m BlindSignRequestModel) Insert(blind_sign *BlindSignRequest) error {
+	query := `
+INSERT INTO blind_sign_requests (user_id, issue_id)
+VALUES ($1, $2)
+RETURNING created`
+
+	args := []interface{}{
+		blind_sign.UserID,
+		blind_sign.IssueID,
+	}
+
+	return m.DB.QueryRow(query, args...).Scan(
+		&blind_sign.Created,
+	)
+}
+
+func (m BlindSignRequestModel) BlindSign(issueID int64, blindedVoteBytes []byte) ([]byte, error) {
+	if issueID < 1 {
+		return nil, ErrRecordNotFound
+	}
+
+	query := `SELECT rsa_private_pem FROM issues WHERE id = $1`
+ 
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
+	defer cancel()
+ 
+	var pemBytes []byte
+	err := m.DB.QueryRowContext(ctx, query, issueID).Scan(&pemBytes)
+	if err != nil {
+		switch {
+		case errors.Is(err, sql.ErrNoRows):
+			return nil, ErrRecordNotFound
+		default:
+			return nil, err
+		}
+	}
+ 
+	key, err := parsePrivateKey(pemBytes)
+	if err != nil {
+		return nil, fmt.Errorf("parse private key: %w", err)
+	}
+ 
+	m_ := new(big.Int).SetBytes(blindedVoteBytes)
+ 
+	// Validate range: m′ must be in [1, n-1]
+	one := big.NewInt(1)
+	if m_.Cmp(one) < 0 || m_.Cmp(key.N) >= 0 {
+		return nil, ErrInvalidBlindedVote
+	}
+ 
+	// s′ = m′^d mod n
+	sig := new(big.Int).Exp(m_, key.D, key.N)
+ 
+	return sig.Bytes(), nil
+}
+
+func parsePrivateKey(pemBytes []byte) (*rsa.PrivateKey, error) {
+	block, _ := pem.Decode(pemBytes)
+	if block == nil {
+		return nil, errors.New("failed to decode PEM block")
+	}
+	return x509.ParsePKCS1PrivateKey(block.Bytes)
+}
+

internal/data/issues.go

@@ -10,13 +10,16 @@ import (
 )
 
 type Issue struct {
-	ID          int64     `json:"id"`
-	Title       string    `json:"title"`
-	Description string    `json:"description"`
-	StartTime   time.Time `json:"start_time"`
-	EndTime     time.Time `json:"end_time"`
-	Created     time.Time `json:"created"`
-	Version     int32     `json:"version"`
+	ID              int64     `json:"id"`
+	Title           string    `json:"title"`
+	Description     string    `json:"description"`
+	StartTime       time.Time `json:"start_time"`
+	EndTime         time.Time `json:"end_time"`
+	N               []byte    `json:"-"`
+    E               int       `json:"-"`
+    PrivatePem      []byte    `json:"-"`
+	Created         time.Time `json:"created"`
+	Version         int32     `json:"version"`
 }
 
 func ValidateIssue(v *validator.Validator, issue *Issue) {
@@ -36,8 +39,8 @@ type IssueModel struct {
 
 func (m IssueModel) Insert(issue *Issue) error {
 	query := `
-INSERT INTO issues (title, description, start_time, end_time)
-VALUES ($1, $2, $3, $4)
+INSERT INTO issues (title, description, start_time, end_time, rsa_n, rsa_e, rsa_private_pem)
+VALUES ($1, $2, $3, $4, $5, $6, $7)
 RETURNING id, created, version`
 
 	args := []interface{}{
@@ -45,6 +48,9 @@ RETURNING id, created, version`
 		issue.Description,
 		issue.StartTime,
 		issue.EndTime,
+		issue.N,
+		issue.E,
+		issue.PrivatePem,
 	}
 
 	return m.DB.QueryRow(query, args...).Scan(
@@ -60,32 +66,26 @@ func (m IssueModel) Get(id int64) (*Issue, error) {
 		return nil, ErrRecordNotFound
 	}
 
-	// Define the SQL query for retrieving the issue data.
-	query :=`
-SELECT id, title, description, start_time, end_time, created, version
+	query := `
+SELECT id, title, description, start_time, end_time, rsa_n, rsa_e, rsa_private_pem, created, version
 FROM issues
 WHERE id = $1`
 
-	// Declare a Issue struct to hold the data returned by the query.
 	var issue Issue
 
-	// Execute the query using the QueryRow() method, passing in the provided id value
-	// as a placeholder parameter, and scan the response data into the fields of the
-	// Issue struct. Importantly, notice that we need to convert the scan target for the
-	// genres column using the pq.Array() adapter function again.
 	err := m.DB.QueryRow(query, id).Scan(
 		&issue.ID,
 		&issue.Title,
 		&issue.Description,
 		&issue.StartTime,
 		&issue.EndTime,
+		&issue.N,
+		&issue.E,
+		&issue.PrivatePem,
 		&issue.Created,
 		&issue.Version,
 	)
 
-	// Handle any errors. If there was no matching issue found, Scan() will return
-	// a sql.ErrNoRows error. We check for this and return our custom ErrRecordNotFound
-	// error instead.
 	if err != nil {
 		switch {
 		case errors.Is(err, sql.ErrNoRows):
@@ -94,29 +94,37 @@ WHERE id = $1`
 			return nil, err
 		}
 	}
-	// Otherwise, return a pointer to the Issue struct.
+
 	return &issue, nil
 }
 
 func (m IssueModel) Update(issue *Issue) error {
 	query := `
 	UPDATE issues
-	SET title = $1, description = $2, start_time = $3, end_time = $4, version = version + 1
-	WHERE id = $5 AND version = $6
+	SET
+		title = $1,
+		description = $2,
+		start_time = $3,
+		end_time = $4,
+		rsa_n = $5,
+		rsa_e = $6,
+		rsa_private_pem = $7,
+		version = version + 1
+	WHERE id = $8 AND version = $9
 	RETURNING version`
 
-	// Create an args slice containing the values for the placeholder parameters.
 	args := []interface{}{
 		issue.Title,
 		issue.Description,
 		issue.StartTime,
 		issue.EndTime,
+		issue.N,
+		issue.E,
+		issue.PrivatePem,
 		issue.ID,
 		issue.Version,
 	}
 
-	// Use the QueryRow() method to execute the query, passing in the args slice as a
-	// variadic parameter and scanning the new version value into the issue struct.
 	err := m.DB.QueryRow(query, args...).Scan(&issue.Version)
 	if err != nil {
 		switch {
@@ -170,7 +178,7 @@ func (m IssueModel) GetAll(title string, filters Filters) ([]*Issue, Metadata, e
 	// Construct the SQL query to retrieve all issue records.
 	query := fmt.Sprintf(`
 	SELECT
-		COUNT(*) OVER(), id, title, description, start_time, end_time, created, version
+		COUNT(*) OVER(), id, title, description, start_time, end_time, rsa_n, rsa_e, rsa_private_pem, created, version
 	FROM
 		issues
 	WHERE
@@ -217,6 +225,9 @@ func (m IssueModel) GetAll(title string, filters Filters) ([]*Issue, Metadata, e
 			&issue.Description,
 			&issue.StartTime,
 			&issue.EndTime,
+			&issue.N,
+			&issue.E,
+			&issue.PrivatePem,
 			&issue.Created,
 			&issue.Version,
 		)

internal/data/models.go

@@ -6,24 +6,27 @@ import (
 )
 
 var (
-	ErrRecordNotFound = errors.New("record not found")
-	ErrEditConflict = errors.New("edit conflict")
+	ErrRecordNotFound     = errors.New("record not found")
+	ErrEditConflict       = errors.New("edit conflict")
+	ErrInvalidBlindedVote = errors.New("invalid blinded vote")
 )
 
 type Models struct {
-	Users          UserModel
-	UserIdentities UserIdentityModel
-	Issues         IssueModel
-	Tokens         TokenModel
-	Permissions    PermissionModel
+	Users             UserModel
+	UserIdentities    UserIdentityModel
+	Issues            IssueModel
+	Tokens            TokenModel
+	Permissions       PermissionModel
+	BlindSignRequests BlindSignRequestModel
 }
 
 func NewModels(db *sql.DB) Models {
 	return Models{
-		Users:          UserModel{DB: db},
-		UserIdentities: UserIdentityModel{DB: db},
-		Issues:         IssueModel{DB: db},
-		Tokens:         TokenModel{DB: db},
-		Permissions:    PermissionModel{DB: db},
+		Users:             UserModel{DB: db},
+		UserIdentities:    UserIdentityModel{DB: db},
+		Issues:            IssueModel{DB: db},
+		Tokens:            TokenModel{DB: db},
+		Permissions:       PermissionModel{DB: db},
+		BlindSignRequests: BlindSignRequestModel{DB: db},
 	}
 }

internal/data/permissions.go

@@ -31,7 +31,7 @@ INNER JOIN users_permissions ON users_permissions.permission_id = permissions.id
 INNER JOIN users ON users_permissions.user_id = users.id
 WHERE users.id = $1`
 
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 	defer cancel()
 
 	rows, err := m.DB.QueryContext(ctx, query, userID)
@@ -62,7 +62,7 @@ func (m PermissionModel) AddForUser(userID int64, codes ...string) error {
 INSERT INTO users_permissions
 SELECT $1, permissions.id FROM permissions WHERE permissions.code = ANY($2)`
 
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 	defer cancel()
 	_, err := m.DB.ExecContext(ctx, query, userID, pq.Array(codes))
 	return err

internal/data/tokens.go

@@ -75,7 +75,7 @@ func (m TokenModel) Insert(token *Token) error {
 
 	args := []interface{}{token.Hash, token.UserID, token.UserIdentityID, token.Expiry, token.Scope}
 
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 	defer cancel()
 
 	_, err := m.DB.ExecContext(ctx, query, args...)

internal/data/user_identities.go

@@ -90,7 +90,7 @@ type UserIdentityModel struct {
 // 		userIdentity.Password.hash,
 // 	}
 
-// 	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+// 	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 // 	defer cancel()
 
 // 	err := m.DB.QueryRowContext(ctx, query, args...).Scan(&userIdentity.ID, &userIdentity.Version)
@@ -214,7 +214,7 @@ AND tokens.expiry > $3`
 
 	var userIdentity UserIdentity
 
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 	defer cancel()
 
 	err := m.DB.QueryRowContext(ctx, query, args...).Scan(
@@ -252,7 +252,7 @@ func (m UserIdentityModel) Update(user *UserIdentity) error {
 		user.Version,
 	}
 
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 	defer cancel()
 
 	err := m.DB.QueryRowContext(ctx, query, args...).Scan(&user.Version)

internal/data/users.go

@@ -23,7 +23,7 @@ type User struct {
 	PhoneNumber string         `json:"phone_number"`
 	Country     string         `json:"country"`
 	Name        string         `json:"name"`
-	AltName     sql.NullString `json:"alt_name"`
+	AltName     *string        `json:"alt_name"`
 	DateOfBirth time.Time      `json:"date_of_birth"`
 	Address     string         `json:"address"`
 	Created     time.Time      `json:"created"`
@@ -60,8 +60,8 @@ func (m UserModel) ExecuteRegistrationTx(user *User, userIdentity *UserIdentity)
 	defer tx.Rollback()
 
 	query := `
-INSERT INTO users (email, phone_number, country, name, alt_name, date_of_birth, address)
-VALUES ($1, $2, $3, $4, $5, $6, $7)
+INSERT INTO users (email, phone_number, country, name, alt_name, date_of_birth, address, activated)
+VALUES ($1, $2, $3, $4, $5, $6, $7, $8)
 RETURNING id, created, last_login, version`
 
 	args := []interface{}{
@@ -72,6 +72,7 @@ RETURNING id, created, last_login, version`
 		user.AltName,
 		user.DateOfBirth,
 		user.Address,
+		user.Activated,
 	}
 	
 	err = tx.QueryRowContext(ctx, query, args...).Scan(&user.ID, &user.Created, &user.LastLogin, &user.Version)
@@ -163,7 +164,7 @@ WHERE id = $1`
 
 func (m UserModel) GetByEmail(email string) (*User, error) {
 	query :=`
-SELECT id, email, phone, country, name, alt_name, date_of_birth, address, created, last_login, activated, version
+SELECT id, email, phone_number, country, name, alt_name, date_of_birth, address, created, last_login, activated, version
 FROM users
 WHERE email = $1`
 
@@ -205,7 +206,17 @@ func (m UserModel) GetForToken(tokenScope, tokenPlaintext string) (*User, error)
 
 	// Set up the SQL query.
 	query :=`
-SELECT users.id, users.email, user.phone_number, user.country, users.name, users.date_of_birth, users.address, users.created, users.activated, users.version
+SELECT
+	users.id,
+	users.email,
+	users.phone_number,
+	users.country,
+	users.name,
+	users.date_of_birth,
+	users.address,
+	users.created,
+	users.activated,
+	users.version
 FROM users
 INNER JOIN tokens ON users.id = tokens.user_id
 WHERE tokens.hash = $1
@@ -218,7 +229,7 @@ AND tokens.expiry > $3`
 	// value to check against the token expiry.
 	args := []interface{}{tokenHash[:], tokenScope, time.Now()}
 	var user User
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 	defer cancel()
 
 	// Execute the query, scanning the return values into a User struct. If no matching
@@ -251,7 +262,16 @@ AND tokens.expiry > $3`
 func (m UserModel) Update(user *User) error {
 	query := `
 	UPDATE users
-	SET email = $1, phone_number = $2, country = $3, name = $4, alt_name = $5, date_of_birth = $6, address = $7, activated = $8, version = version + 1
+	SET
+		email = $1,
+		phone_number = $2,
+		country = $3,
+		name = $4,
+		alt_name = $5,
+		date_of_birth = $6,
+		address = $7,
+		activated = $8,
+		version = version + 1
 	WHERE id = $9 AND version = $10
 	RETURNING version`
 
@@ -269,7 +289,7 @@ func (m UserModel) Update(user *User) error {
 		user.Version,
 	}
 
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 3 * time.Second)
 	defer cancel()
 
 	err := m.DB.QueryRowContext(ctx, query, args...).Scan(&user.Version)

internal/jsonlog/jsonlog.go

@@ -1,26 +1,23 @@
 package jsonlog
 
 import (
-"encoding/json"
-"io"
-"os"
-"runtime/debug"
-"sync"
-"time"
+	"encoding/json"
+	"io"
+	"os"
+	"runtime/debug"
+	"sync"
+	"time"
 )
-// Define a Level type to represent the severity level for a log entry.
+
 type Level int8
 
-// Initialize constants which represent a specific severity level. We use the iota
-// keyword as a shortcut to assign successive integer values to the constants.
 const (
-	LevelInfo Level = iota // Has the value 0.
-	LevelError // Has the value 1.
-	LevelFatal // Has the value 2.
-	LevelOff // Has the value 3.
+	LevelInfo Level = iota
+	LevelError
+	LevelFatal
+	LevelOff
 )
 
-// Return a human-friendly string for the severity level.
 func (l Level) String() string {
 	switch l {
 	case LevelInfo:
@@ -34,17 +31,12 @@ func (l Level) String() string {
 	}
 }
 
-// Define a custom Logger type. This holds the output destination that the log entries
-// will be written to, the minimum severity level that log entries will be written for,
-// plus a mutex for coordinating the writes.
 type Logger struct {
 	out      io.Writer
 	minLevel Level
 	mu       sync.Mutex
 }
 
-// Return a new Logger instance which writes log entries at or above a minimum severity
-// level to a specific output destination.
 func New(out io.Writer, minLevel Level) *Logger {
 	return &Logger{
 	out: out,
@@ -52,9 +44,6 @@ func New(out io.Writer, minLevel Level) *Logger {
 	}
 }
 
-// Declare some helper methods for writing log entries at the different levels. Notice
-// that these all accept a map as the second parameter which can contain any arbitrary
-// 'properties' that you want to appear in the log entry.
 func (l *Logger) PrintInfo(message string, properties map[string]string) {
 	l.print(LevelInfo, message, properties)
 }
@@ -65,18 +54,14 @@ func (l *Logger) PrintError(err error, properties map[string]string) {
 
 func (l *Logger) PrintFatal(err error, properties map[string]string) {
 	l.print(LevelFatal, err.Error(), properties)
-	os.Exit(1) // For entries at the FATAL level, we also terminate the application.
+	os.Exit(1)
 }
 
-// Print is an internal method for writing the log entry.
 func (l *Logger) print(level Level, message string, properties map[string]string) (int, error) {
-	// If the severity level of the log entry is below the minimum severity for the
-	// logger, then return with no further action.
 	if level < l.minLevel {
 		return 0, nil
 	}
 
-	// Declare an anonymous struct holding the data for the log entry.
 	aux := struct {
 		Level      string            `json:"level"`
 		Time       string            `json:"time"`
@@ -90,35 +75,23 @@ func (l *Logger) print(level Level, message string, properties map[string]string
 		Properties: properties,
 	}
 
-	// Include a stack trace for entries at the ERROR and FATAL levels.
 	if level >= LevelError {
 		aux.Trace = string(debug.Stack())
 	}
 
-	// Declare a line variable for holding the actual log entry text.
 	var line []byte
 
-	// Marshal the anonymous struct to JSON and store it in the line variable. If there
-	// was a problem creating the JSON, set the contents of the log entry to be that
-	// plain-text error message instead.
 	line, err := json.Marshal(aux)
 	if err != nil {
 		line = []byte(LevelError.String() + ": unable to marshal log message:" + err.Error())
 	}
 
-	// Lock the mutex so that no two writes to the output destination cannot happen
-	// concurrently. If we don't do this, it's possible that the text for two or more
-	// log entries will be intermingled in the output.
 	l.mu.Lock()
 	defer l.mu.Unlock()
 
-	// Write the log entry followed by a newline.
 	return l.out.Write(append(line, '\n'))
 }
 
-// We also implement a Write() method on our Logger type so that it satisfies the
-// io.Writer interface. This writes a log entry at the ERROR level with no additional
-// properties.
 func (l *Logger) Write(message []byte) (n int, err error) {
 	return l.print(LevelError, string(message), nil)
 }

internal/mailer/templates/user_welcome.tmpl

@@ -26,7 +26,7 @@ The DigitalePartei Team
     <p>Hi,</p>
     <p>Thanks for signing up for a Digitale Partei Österreich account. We're excited to have you on board!</p>
     <p>For future reference, your user ID number is {{.ID}}.</p>
-    <p>Your activation token is {{.token}}</p>
+    <p><a href="dpoe://activate?token={{.token}}">Click here to activate!</a></p>
     <p>Thanks,</p>
     <p>The DigitalePartei Team</p>
 </body>

migrations/000001_create_users_table.up.sql

@@ -13,18 +13,18 @@ CREATE TABLE IF NOT EXISTS users (
     version INT NOT NULL DEFAULT 1
 );
 
-CREATE TABLE IF NOT EXISTS auth_provider (
+CREATE TABLE IF NOT EXISTS auth_providers (
     id BIGSERIAL PRIMARY KEY, -- e.g., 'local', 'id_austria',
     description TEXT NOT NULL,
     active BOOLEAN DEFAULT false
 );
 
-INSERT INTO auth_provider (description, active) VALUES ('local', true);
-INSERT INTO auth_provider (description, active) VALUES ('id_austria', false);
+INSERT INTO auth_providers (description, active) VALUES ('local', true);
+INSERT INTO auth_providers (description, active) VALUES ('id_austria', false);
 
 CREATE TABLE IF NOT EXISTS user_identities (
     id BIGSERIAL PRIMARY KEY,
-    provider_id BIGINT NOT NULL REFERENCES auth_provider(id),
+    provider_id BIGINT NOT NULL REFERENCES auth_providers(id),
     user_id BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
     
     -- For local: the username. For OIDC: the 'sub' (Subject ID)
@@ -33,9 +33,9 @@ CREATE TABLE IF NOT EXISTS user_identities (
     -- Nullable because OIDC users won't have a password in your DB
     password bytea,
 
-    version INT NOT NULL DEFAULT 1,
+    version INT NOT NULL DEFAULT 1
     
-    UNIQUE(provider_id, provider_user_id)
+    -- UNIQUE(provider_id, provider_user_id)
 );
 
 -- INSERT INTO users(

migrations/000002_create_additional_tables.down.sql

@@ -3,6 +3,7 @@ DROP INDEX IF EXISTS idx_vote_tokens_issue_id;
 DROP INDEX IF EXISTS idx_options_issue_id;
 
 DROP TABLE IF EXISTS votes;
+DROP TABLE IF EXISTS blind_sign_requests;
 DROP TABLE IF EXISTS vote_tokens;
 DROP TABLE IF EXISTS options;
 DROP TABLE IF EXISTS issues;

migrations/000002_create_additional_tables.up.sql

@@ -4,6 +4,9 @@ CREATE TABLE IF NOT EXISTS issues (
     description TEXT,
     start_time TIMESTAMPTZ NOT NULL,
     end_time TIMESTAMPTZ NOT NULL,
+    rsa_n BYTEA,
+    rsa_e INT,
+    rsa_private_pem BYTEA,
     created TIMESTAMPTZ NOT NULL DEFAULT now(),
     version INT NOT NULL DEFAULT 1
 );
@@ -25,6 +28,13 @@ CREATE TABLE IF NOT EXISTS vote_tokens (
     version INT NOT NULL DEFAULT 1
 );
 
+CREATE TABLE IF NOT EXISTS blind_sign_requests (
+    user_id  BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    issue_id BIGINT NOT NULL REFERENCES issues(id) ON DELETE CASCADE,
+    created  TIMESTAMPTZ NOT NULL DEFAULT now(),
+    PRIMARY KEY (user_id, issue_id)
+);
+
 CREATE TABLE IF NOT EXISTS votes (
     id BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
     token UUID NOT NULL UNIQUE REFERENCES vote_tokens(token) ON DELETE CASCADE,