fix(auth): owner allowlist trusts pass-through-authenticated callers (#59)

Allowlist.Check now takes ctx: when the caller authenticated with
their own Gitea PAT (pass-through, v0.12.0), it skips the static
GITEA_MCP_ALLOWED_OWNERS check entirely — Gitea's own permission
model already gates that caller's access more precisely than a coarse
owner-name list can. The static list still applies unchanged for the
shared static-token/JWT path, where it's the only defense against the
service token's blast radius.

Mechanical: every tool call site already had ctx in scope, so this is
a signature-only change at 41 call sites, no other tool behavior
changes. Closes the "Deferred" item from #59.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

internal/allowlist/allowlist.go

@@ -1,6 +1,11 @@
 package allowlist
 
-import "fmt"
+import (
+	"context"
+	"fmt"
+
+	"git.d-ma.be/mathias/gitea-mcp/internal/gitea"
+)
 
 type Allowlist struct {
 	owners map[string]struct{}
@@ -14,10 +19,17 @@ func New(owners []string) *Allowlist {
 	return &Allowlist{owners: m}
 }
 
-func (a *Allowlist) Check(owner string) error {
+// Check gates owner access to the static list — except for a caller
+// authenticated with their own Gitea PAT (pass-through, gitea-mcp#59), whose
+// access Gitea's own permission model already gates more precisely than a
+// coarse owner name list ever could.
+func (a *Allowlist) Check(ctx context.Context, owner string) error {
 	if owner == "" {
 		return fmt.Errorf("owner required")
 	}
+	if _, ok := gitea.TokenFromContext(ctx); ok {
+		return nil
+	}
 	if _, ok := a.owners[owner]; !ok {
 		return fmt.Errorf("owner %q not in allowlist", owner)
 	}

internal/allowlist/allowlist_test.go

@@ -1,16 +1,36 @@
 package allowlist_test
 
 import (
+	"context"
 	"testing"
 
 	"git.d-ma.be/mathias/gitea-mcp/internal/allowlist"
+	"git.d-ma.be/mathias/gitea-mcp/internal/gitea"
 	"github.com/stretchr/testify/assert"
 )
 
 func TestAllowlistCheck(t *testing.T) {
 	a := allowlist.New([]string{"mathias", "acme"})
-	assert.NoError(t, a.Check("mathias"))
+	ctx := context.Background()
-	assert.NoError(t, a.Check("acme"))
+	assert.NoError(t, a.Check(ctx, "mathias"))
-	assert.Error(t, a.Check("evil"))
+	assert.NoError(t, a.Check(ctx, "acme"))
-	assert.Error(t, a.Check(""))
+	assert.Error(t, a.Check(ctx, "evil"))
+	assert.Error(t, a.Check(ctx, ""))
+}
+
+// A caller authenticated with their own Gitea PAT (pass-through, gitea-mcp#59)
+// is gated by Gitea's own permission model, not the MCP's static owner list —
+// otherwise a legitimate second user could never touch their own repos.
+func TestAllowlistCheckTrustsPassthroughAuthenticatedCaller(t *testing.T) {
+	a := allowlist.New([]string{"mathias"})
+	ctx := gitea.WithToken(context.Background(), "someone-elses-pat")
+	assert.NoError(t, a.Check(ctx, "someone-else"))
+}
+
+// Empty owner is a structural input error, not an authz question — still
+// rejected even on the pass-through path.
+func TestAllowlistCheckStillRejectsEmptyOwnerOnPassthrough(t *testing.T) {
+	a := allowlist.New([]string{"mathias"})
+	ctx := gitea.WithToken(context.Background(), "someone-elses-pat")
+	assert.Error(t, a.Check(ctx, ""))
 }

internal/tools/branch_delete.go

@@ -46,7 +46,7 @@ func (t *BranchDelete) Call(ctx context.Context, raw json.RawMessage) (json.RawM
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Branch == "" {

internal/tools/branch_list.go

@@ -47,7 +47,7 @@ func (t *BranchList) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 

internal/tools/branch_protection_get.go

@@ -45,7 +45,7 @@ func (t *BranchProtectionGet) Call(ctx context.Context, raw json.RawMessage) (js
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 

internal/tools/code_search.go

@@ -70,7 +70,7 @@ func (t *CodeSearch) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if args.Q == "" {
 		return nil, fmt.Errorf("q is required: %w", gitea.ErrValidation)
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Page < 1 {

internal/tools/create_project_from_template.go

@@ -111,7 +111,7 @@ func (t *CreateProjectFromTemplate) Call(ctx context.Context, raw json.RawMessag
 	}
 
 	// Allowlist check first.
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 

internal/tools/dir_list.go

@@ -47,7 +47,7 @@ func (t *DirList) Call(ctx context.Context, raw json.RawMessage) (json.RawMessag
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 

internal/tools/file_delete.go

@@ -52,7 +52,7 @@ func (t *FileDelete) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Sha == "" {

internal/tools/file_read.go

@@ -51,7 +51,7 @@ func (t *FileRead) Call(ctx context.Context, raw json.RawMessage) (json.RawMessa
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 

internal/tools/file_write_branch.go

@@ -57,7 +57,7 @@ func (t *FileWriteBranch) Call(ctx context.Context, raw json.RawMessage) (json.R
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Branch == "" {

internal/tools/issue_close.go

@@ -45,7 +45,7 @@ func (t *IssueClose) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	iss, err := t.c.SetIssueState(ctx, args.Owner, args.Repo, args.Number, "closed")

internal/tools/issue_comment.go

@@ -50,7 +50,7 @@ func (t *IssueComment) Call(ctx context.Context, raw json.RawMessage) (json.RawM
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Number < 1 {

internal/tools/issue_create.go

@@ -56,7 +56,7 @@ func (t *IssueCreate) Call(ctx context.Context, raw json.RawMessage) (json.RawMe
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Title == "" {

internal/tools/issue_edit.go

@@ -53,7 +53,7 @@ func (t *IssueEdit) Call(ctx context.Context, raw json.RawMessage) (json.RawMess
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Number < 1 {

internal/tools/issue_get.go

@@ -43,7 +43,7 @@ func (t *IssueGet) Call(ctx context.Context, raw json.RawMessage) (json.RawMessa
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	iss, err := t.c.GetIssue(ctx, args.Owner, args.Repo, args.Number)

internal/tools/issue_label.go

@@ -50,7 +50,7 @@ func (t *IssueLabel) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Number < 1 {

internal/tools/issue_list.go

@@ -53,7 +53,7 @@ func (t *IssueList) Call(ctx context.Context, raw json.RawMessage) (json.RawMess
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.State == "" {

internal/tools/issue_list_comments.go

@@ -45,7 +45,7 @@ func (t *IssueListComments) Call(ctx context.Context, raw json.RawMessage) (json
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	comments, err := t.c.ListIssueComments(ctx, args.Owner, args.Repo, args.Number)

internal/tools/issue_reopen.go

@@ -45,7 +45,7 @@ func (t *IssueReopen) Call(ctx context.Context, raw json.RawMessage) (json.RawMe
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	iss, err := t.c.SetIssueState(ctx, args.Owner, args.Repo, args.Number, "open")

internal/tools/label_list.go

@@ -43,7 +43,7 @@ func (t *LabelList) Call(ctx context.Context, raw json.RawMessage) (json.RawMess
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	labels, err := t.c.ListLabels(ctx, args.Owner, args.Repo)

internal/tools/pr_comment.go

@@ -50,7 +50,7 @@ func (t *PRComment) Call(ctx context.Context, raw json.RawMessage) (json.RawMess
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Number < 1 {

internal/tools/pr_create.go

@@ -56,7 +56,7 @@ func (t *PRCreate) Call(ctx context.Context, raw json.RawMessage) (json.RawMessa
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Title == "" {

internal/tools/pr_files_diff.go

@@ -63,7 +63,7 @@ func (t *PRFilesDiff) Call(ctx context.Context, raw json.RawMessage) (json.RawMe
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Number < 1 {

internal/tools/pr_get.go

@@ -44,7 +44,7 @@ func (t *PRGet) Call(ctx context.Context, raw json.RawMessage) (json.RawMessage,
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Number < 1 {

internal/tools/pr_list.go

@@ -51,7 +51,7 @@ func (t *PRList) Call(ctx context.Context, raw json.RawMessage) (json.RawMessage
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	state := args.State

internal/tools/pr_merge.go

@@ -52,7 +52,7 @@ func (t *PRMerge) Call(ctx context.Context, raw json.RawMessage) (json.RawMessag
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Number < 1 {

internal/tools/release_create.go

@@ -55,7 +55,7 @@ func (t *ReleaseCreate) Call(ctx context.Context, raw json.RawMessage) (json.Raw
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	rel, err := t.c.CreateRelease(ctx, args.Owner, args.Repo, gitea.CreateReleaseArgs{

internal/tools/repo_create.go

@@ -53,7 +53,7 @@ func (t *RepoCreate) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	createArgs := gitea.CreateRepoArgs{

internal/tools/repo_delete.go

@@ -46,7 +46,7 @@ func (t *RepoDelete) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Confirm != args.Repo {

internal/tools/repo_get.go

@@ -38,7 +38,7 @@ func (t *RepoGet) Call(ctx context.Context, raw json.RawMessage) (json.RawMessag
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	r, err := t.c.GetRepo(ctx, args.Owner, args.Repo)

internal/tools/repo_list.go

@@ -45,7 +45,7 @@ func (t *RepoList) Call(ctx context.Context, raw json.RawMessage) (json.RawMessa
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	args.Limit = capLimit(args.Limit, 30)

internal/tools/repo_mirror_push.go

@@ -96,7 +96,7 @@ func (t *RepoMirrorPush) Call(ctx context.Context, raw json.RawMessage) (json.Ra
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	switch args.Action {

internal/tools/repo_search.go

@@ -53,7 +53,7 @@ func (t *RepoSearch) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 		return nil, fmt.Errorf("q is required: %w", gitea.ErrValidation)
 	}
 	if args.Owner != "" {
-		if err := t.a.Check(args.Owner); err != nil {
+		if err := t.a.Check(ctx, args.Owner); err != nil {
 			return nil, err
 		}
 	}
@@ -75,7 +75,7 @@ func (t *RepoSearch) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 			if len(parts) != 2 {
 				continue
 			}
-			if t.a.Check(parts[0]) == nil {
+			if t.a.Check(ctx, parts[0]) == nil {
 				filtered = append(filtered, r)
 			}
 		}

internal/tools/repo_status.go

@@ -45,7 +45,7 @@ func (t *RepoStatus) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 

internal/tools/repo_topics_update.go

@@ -45,7 +45,7 @@ func (t *RepoTopicsUpdate) Call(ctx context.Context, raw json.RawMessage) (json.
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if err := t.c.UpdateTopics(ctx, args.Owner, args.Repo, args.Topics); err != nil {

internal/tools/repo_tree.go

@@ -45,7 +45,7 @@ func (t *RepoTree) Call(ctx context.Context, raw json.RawMessage) (json.RawMessa
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	tree, err := t.c.GetTree(ctx, args.Owner, args.Repo, args.Ref, true)

internal/tools/repo_update.go

@@ -60,7 +60,7 @@ func (t *RepoUpdate) Call(ctx context.Context, raw json.RawMessage) (json.RawMes
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 

internal/tools/tag_create.go

@@ -50,7 +50,7 @@ func (t *TagCreate) Call(ctx context.Context, raw json.RawMessage) (json.RawMess
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Tag == "" {

internal/tools/tbd_ship.go

@@ -145,7 +145,7 @@ func (t *TBDShip) Call(ctx context.Context, raw json.RawMessage) (json.RawMessag
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Path == "" || args.Content == "" || args.Message == "" {

internal/tools/workflow_run_list.go

@@ -57,7 +57,7 @@ func (t *WorkflowRunList) Call(ctx context.Context, raw json.RawMessage) (json.R
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	args.Limit = capLimit(args.Limit, 10)

internal/tools/workflow_run_status.go

@@ -47,7 +47,7 @@ func (t *WorkflowRunStatus) Call(ctx context.Context, raw json.RawMessage) (json
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.RunID < 1 {

internal/tools/workflow_run_trigger.go

@@ -62,7 +62,7 @@ func (t *WorkflowRunTrigger) Call(ctx context.Context, raw json.RawMessage) (jso
 	if err := parseArgs(raw, &args); err != nil {
 		return nil, err
 	}
-	if err := t.a.Check(args.Owner); err != nil {
+	if err := t.a.Check(ctx, args.Owner); err != nil {
 		return nil, err
 	}
 	if args.Workflow == "" {