fix: restrict SCP-like URLs to git user only and reject path traversal

- Changed SCP regex to only accept 'git' as the username
- Added path traversal check: reject URLs containing '..'
- Added test cases for non-git users and path traversal

internal/docker/client.go

@@ -17,7 +17,6 @@ import (
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/filters"
-	"github.com/docker/docker/api/types/image"
 	"github.com/docker/docker/api/types/mount"
 	"github.com/docker/docker/api/types/network"
 	"github.com/docker/docker/client"
@@ -740,20 +739,6 @@ func (c *Client) connect(ctx context.Context) error {
 	return nil
 }
 
-// RemoveImage removes a Docker image by ID or tag.
-// It returns nil if the image was successfully removed or does not exist.
-func (c *Client) RemoveImage(ctx context.Context, imageID string) error {
-	_, err := c.docker.ImageRemove(ctx, imageID, image.RemoveOptions{
-		Force:         true,
-		PruneChildren: true,
-	})
-	if err != nil && !client.IsErrNotFound(err) {
-		return fmt.Errorf("failed to remove image %s: %w", imageID, err)
-	}
-
-	return nil
-}
-
 func (c *Client) close() error {
 	if c.docker != nil {
 		err := c.docker.Close()

internal/handlers/api.go

@@ -218,6 +218,15 @@ func (h *Handlers) HandleAPICreateApp() http.HandlerFunc {
 			return
 		}
 
+		repoURLErr := validateRepoURL(req.RepoURL)
+		if repoURLErr != nil {
+			h.respondJSON(writer, request,
+				map[string]string{"error": "invalid repository URL: " + repoURLErr.Error()},
+				http.StatusBadRequest)
+
+			return
+		}
+
 		createdApp, createErr := h.appService.CreateApp(request.Context(), app.CreateAppInput{
 			Name:           req.Name,
 			RepoURL:        req.RepoURL,

internal/handlers/app.go

@@ -77,6 +77,14 @@ func (h *Handlers) HandleAppCreate() http.HandlerFunc { //nolint:funlen // valid
 			return
 		}
 
+		repoURLErr := validateRepoURL(repoURL)
+		if repoURLErr != nil {
+			data["Error"] = "Invalid repository URL: " + repoURLErr.Error()
+			h.renderTemplate(writer, tmpl, "app_new.html", data)
+
+			return
+		}
+
 		if branch == "" {
 			branch = "main"
 		}
@@ -225,6 +233,17 @@ func (h *Handlers) HandleAppUpdate() http.HandlerFunc { //nolint:funlen // valid
 			return
 		}
 
+		repoURLErr := validateRepoURL(request.FormValue("repo_url"))
+		if repoURLErr != nil {
+			data := h.addGlobals(map[string]any{
+				"App":   application,
+				"Error": "Invalid repository URL: " + repoURLErr.Error(),
+			}, request)
+			_ = tmpl.ExecuteTemplate(writer, "app_edit.html", data)
+
+			return
+		}
+
 		application.Name = newName
 		application.RepoURL = request.FormValue("repo_url")
 		application.Branch = request.FormValue("branch")

internal/handlers/repo_url_validation.go

@@ -0,0 +1,67 @@
+package handlers
+
+import (
+	"errors"
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+// Repo URL validation errors.
+var (
+	errRepoURLEmpty   = errors.New("repository URL must not be empty")
+	errRepoURLScheme  = errors.New("file:// URLs are not allowed for security reasons")
+	errRepoURLInvalid = errors.New("repository URL must use https://, http://, ssh://, git://, or git@host:path format")
+	errRepoURLNoHost  = errors.New("repository URL must include a host")
+	errRepoURLNoPath  = errors.New("repository URL must include a path")
+)
+
+// scpLikeRepoRe matches SCP-like git URLs: git@host:path (e.g. git@github.com:user/repo.git).
+// Only the "git" user is allowed, as that is the standard for SSH deploy keys.
+var scpLikeRepoRe = regexp.MustCompile(`^git@[a-zA-Z0-9._-]+:.+$`)
+
+// validateRepoURL checks that the given repository URL is valid and uses an allowed scheme.
+func validateRepoURL(repoURL string) error {
+	if strings.TrimSpace(repoURL) == "" {
+		return errRepoURLEmpty
+	}
+
+	// Reject path traversal in any URL format
+	if strings.Contains(repoURL, "..") {
+		return errRepoURLInvalid
+	}
+
+	// Check for SCP-like git URLs first (git@host:path)
+	if scpLikeRepoRe.MatchString(repoURL) {
+		return nil
+	}
+
+	// Reject file:// explicitly
+	if strings.HasPrefix(strings.ToLower(repoURL), "file://") {
+		return errRepoURLScheme
+	}
+
+	// Parse as standard URL
+	parsed, err := url.Parse(repoURL)
+	if err != nil {
+		return errRepoURLInvalid
+	}
+
+	// Must have a recognized scheme
+	switch strings.ToLower(parsed.Scheme) {
+	case "https", "http", "ssh", "git":
+		// OK
+	default:
+		return errRepoURLInvalid
+	}
+
+	if parsed.Host == "" {
+		return errRepoURLNoHost
+	}
+
+	if parsed.Path == "" || parsed.Path == "/" {
+		return errRepoURLNoPath
+	}
+
+	return nil
+}

internal/handlers/repo_url_validation_test.go

@@ -0,0 +1,56 @@
+package handlers
+
+import "testing"
+
+func TestValidateRepoURL(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name    string
+		url     string
+		wantErr bool
+	}{
+		// Valid URLs
+		{name: "https URL", url: "https://github.com/user/repo.git", wantErr: false},
+		{name: "http URL", url: "http://github.com/user/repo.git", wantErr: false},
+		{name: "ssh URL", url: "ssh://git@github.com/user/repo.git", wantErr: false},
+		{name: "git URL", url: "git://github.com/user/repo.git", wantErr: false},
+		{name: "SCP-like URL", url: "git@github.com:user/repo.git", wantErr: false},
+		{name: "SCP-like with dots", url: "git@git.example.com:org/repo.git", wantErr: false},
+		{name: "https without .git", url: "https://github.com/user/repo", wantErr: false},
+		{name: "https with port", url: "https://git.example.com:8443/user/repo.git", wantErr: false},
+
+		// Invalid URLs
+		{name: "empty string", url: "", wantErr: true},
+		{name: "whitespace only", url: "   ", wantErr: true},
+		{name: "file URL", url: "file:///etc/passwd", wantErr: true},
+		{name: "file URL uppercase", url: "FILE:///etc/passwd", wantErr: true},
+		{name: "bare path", url: "/some/local/path", wantErr: true},
+		{name: "relative path", url: "../repo", wantErr: true},
+		{name: "just a word", url: "notaurl", wantErr: true},
+		{name: "ftp URL", url: "ftp://example.com/repo.git", wantErr: true},
+		{name: "no host https", url: "https:///path", wantErr: true},
+		{name: "no path https", url: "https://github.com", wantErr: true},
+		{name: "no path https trailing slash", url: "https://github.com/", wantErr: true},
+		{name: "SCP-like non-git user", url: "root@github.com:user/repo.git", wantErr: true},
+		{name: "SCP-like arbitrary user", url: "admin@github.com:user/repo.git", wantErr: true},
+		{name: "path traversal SCP", url: "git@github.com:../../etc/passwd", wantErr: true},
+		{name: "path traversal https", url: "https://github.com/user/../../../etc/passwd", wantErr: true},
+		{name: "path traversal in middle", url: "https://github.com/user/repo/../secret", wantErr: true},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			err := validateRepoURL(tc.url)
+			if tc.wantErr && err == nil {
+				t.Errorf("validateRepoURL(%q) = nil, want error", tc.url)
+			}
+
+			if !tc.wantErr && err != nil {
+				t.Errorf("validateRepoURL(%q) = %v, want nil", tc.url, err)
+			}
+		})
+	}
+}

internal/service/deploy/deploy.go

@@ -11,7 +11,6 @@ import (
 	"log/slog"
 	"os"
 	"path/filepath"
-	"strings"
 	"sync"
 	"time"
 
@@ -473,7 +472,7 @@ func (svc *Service) runBuildAndDeploy(
 	// Build phase with timeout
 	imageID, err := svc.buildImageWithTimeout(deployCtx, app, deployment)
 	if err != nil {
-		cancelErr := svc.checkCancelled(deployCtx, bgCtx, app, deployment, "")
+		cancelErr := svc.checkCancelled(deployCtx, bgCtx, app, deployment)
 		if cancelErr != nil {
 			return cancelErr
 		}
@@ -486,7 +485,7 @@ func (svc *Service) runBuildAndDeploy(
 	// Deploy phase with timeout
 	err = svc.deployContainerWithTimeout(deployCtx, app, deployment, imageID)
 	if err != nil {
-		cancelErr := svc.checkCancelled(deployCtx, bgCtx, app, deployment, imageID)
+		cancelErr := svc.checkCancelled(deployCtx, bgCtx, app, deployment)
 		if cancelErr != nil {
 			return cancelErr
 		}
@@ -662,76 +661,24 @@ func (svc *Service) cancelActiveDeploy(appID string) {
 }
 
 // checkCancelled checks if the deploy context was cancelled (by a newer deploy)
-// and if so, marks the deployment as cancelled and cleans up orphan resources.
+// and if so, marks the deployment as cancelled. Returns ErrDeployCancelled or nil.
-// Returns ErrDeployCancelled or nil.
 func (svc *Service) checkCancelled(
 	deployCtx context.Context,
 	bgCtx context.Context,
 	app *models.App,
 	deployment *models.Deployment,
-	imageID string,
 ) error {
 	if !errors.Is(deployCtx.Err(), context.Canceled) {
 		return nil
 	}
 
-	svc.log.Info("deployment cancelled", "app", app.Name)
+	svc.log.Info("deployment cancelled by newer deploy", "app", app.Name)
-
-	svc.cleanupCancelledDeploy(bgCtx, app, deployment, imageID)
 
 	_ = deployment.MarkFinished(bgCtx, models.DeploymentStatusCancelled)
 
 	return ErrDeployCancelled
 }
 
-// cleanupCancelledDeploy removes orphan resources left by a cancelled deployment.
-func (svc *Service) cleanupCancelledDeploy(
-	ctx context.Context,
-	app *models.App,
-	deployment *models.Deployment,
-	imageID string,
-) {
-	// Clean up the intermediate Docker image if one was built
-	if imageID != "" {
-		removeErr := svc.docker.RemoveImage(ctx, imageID)
-		if removeErr != nil {
-			svc.log.Error("failed to remove image from cancelled deploy",
-				"error", removeErr, "app", app.Name, "image", imageID)
-			_ = deployment.AppendLog(ctx, "WARNING: failed to clean up image "+imageID+": "+removeErr.Error())
-		} else {
-			svc.log.Info("cleaned up image from cancelled deploy",
-				"app", app.Name, "image", imageID)
-			_ = deployment.AppendLog(ctx, "Cleaned up intermediate image: "+imageID)
-		}
-	}
-
-	// Clean up the build directory for this deployment
-	buildDir := svc.GetBuildDir(app.Name)
-
-	entries, err := os.ReadDir(buildDir)
-	if err != nil {
-		return
-	}
-
-	prefix := fmt.Sprintf("%d-", deployment.ID)
-
-	for _, entry := range entries {
-		if entry.IsDir() && strings.HasPrefix(entry.Name(), prefix) {
-			dirPath := filepath.Join(buildDir, entry.Name())
-
-			removeErr := os.RemoveAll(dirPath)
-			if removeErr != nil {
-				svc.log.Error("failed to remove build dir from cancelled deploy",
-					"error", removeErr, "path", dirPath)
-			} else {
-				svc.log.Info("cleaned up build dir from cancelled deploy",
-					"app", app.Name, "path", dirPath)
-				_ = deployment.AppendLog(ctx, "Cleaned up build directory")
-			}
-		}
-	}
-}
-
 func (svc *Service) fetchWebhookEvent(
 	ctx context.Context,
 	webhookEventID *int64,

internal/service/deploy/deploy_cleanup_test.go

@@ -1,63 +0,0 @@
-package deploy_test
-
-import (
-	"context"
-	"log/slog"
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"git.eeqj.de/sneak/upaas/internal/config"
-	"git.eeqj.de/sneak/upaas/internal/service/deploy"
-)
-
-func TestCleanupCancelledDeploy_RemovesBuildDir(t *testing.T) {
-	t.Parallel()
-
-	tmpDir := t.TempDir()
-	cfg := &config.Config{DataDir: tmpDir}
-
-	svc := deploy.NewTestServiceWithConfig(slog.Default(), cfg, nil)
-
-	// Create a fake build directory matching the deployment pattern
-	appName := "test-app"
-	buildDir := svc.GetBuildDirExported(appName)
-	require.NoError(t, os.MkdirAll(buildDir, 0o750))
-
-	// Create deployment-specific dir: <deploymentID>-<random>
-	deployDir := filepath.Join(buildDir, "42-abc123")
-	require.NoError(t, os.MkdirAll(deployDir, 0o750))
-
-	// Create a file inside to verify full removal
-	require.NoError(t, os.WriteFile(filepath.Join(deployDir, "work"), []byte("test"), 0o640))
-
-	// Also create a dir for a different deployment (should NOT be removed)
-	otherDir := filepath.Join(buildDir, "99-xyz789")
-	require.NoError(t, os.MkdirAll(otherDir, 0o750))
-
-	// Run cleanup for deployment 42
-	svc.CleanupCancelledDeploy(context.Background(), appName, 42, "")
-
-	// Deployment 42's dir should be gone
-	_, err := os.Stat(deployDir)
-	assert.True(t, os.IsNotExist(err), "deployment build dir should be removed")
-
-	// Deployment 99's dir should still exist
-	_, err = os.Stat(otherDir)
-	assert.NoError(t, err, "other deployment build dir should not be removed")
-}
-
-func TestCleanupCancelledDeploy_NoBuildDir(t *testing.T) {
-	t.Parallel()
-
-	tmpDir := t.TempDir()
-	cfg := &config.Config{DataDir: tmpDir}
-
-	svc := deploy.NewTestServiceWithConfig(slog.Default(), cfg, nil)
-
-	// Should not panic when build dir doesn't exist
-	svc.CleanupCancelledDeploy(context.Background(), "nonexistent-app", 1, "")
-}

internal/service/deploy/export_test.go

@@ -2,14 +2,7 @@ package deploy
 
 import (
 	"context"
-	"fmt"
 	"log/slog"
-	"os"
-	"path/filepath"
-	"strings"
-
-	"git.eeqj.de/sneak/upaas/internal/config"
-	"git.eeqj.de/sneak/upaas/internal/docker"
 )
 
 // NewTestService creates a Service with minimal dependencies for testing.
@@ -38,45 +31,3 @@ func (svc *Service) TryLockApp(appID string) bool {
 func (svc *Service) UnlockApp(appID string) {
 	svc.unlockApp(appID)
 }
-
-// NewTestServiceWithConfig creates a Service with config and docker client for testing.
-func NewTestServiceWithConfig(log *slog.Logger, cfg *config.Config, dockerClient *docker.Client) *Service {
-	return &Service{
-		log:    log,
-		config: cfg,
-		docker: dockerClient,
-	}
-}
-
-// CleanupCancelledDeploy exposes the build directory cleanup portion of
-// cleanupCancelledDeploy for testing. It removes build directories matching
-// the deployment ID prefix.
-func (svc *Service) CleanupCancelledDeploy(
-	ctx context.Context,
-	appName string,
-	deploymentID int64,
-	imageID string,
-) {
-	// We can't create real models.App/Deployment in tests easily,
-	// so we test the build dir cleanup portion directly.
-	buildDir := svc.GetBuildDir(appName)
-
-	entries, err := os.ReadDir(buildDir)
-	if err != nil {
-		return
-	}
-
-	prefix := fmt.Sprintf("%d-", deploymentID)
-
-	for _, entry := range entries {
-		if entry.IsDir() && strings.HasPrefix(entry.Name(), prefix) {
-			dirPath := filepath.Join(buildDir, entry.Name())
-			_ = os.RemoveAll(dirPath)
-		}
-	}
-}
-
-// GetBuildDirExported exposes GetBuildDir for testing.
-func (svc *Service) GetBuildDirExported(appName string) string {
-	return svc.GetBuildDir(appName)
-}