hscontrol/api/v1: implement auth and policy endpoints

AuthRegister/Approve/Reject and GetPolicy/SetPolicy/CheckPolicy over the state
layer, completing all v1 operations. HTTP-parity tests included.

hscontrol/api/v1/auth.go

@@ -2,11 +2,15 @@ package apiv1
 
 import (
 	"context"
+	"errors"
 	"net/http"
 
 	oas "github.com/juanfont/headscale/gen/api/v1"
+	"github.com/juanfont/headscale/hscontrol/types"
 )
 
+var errAuthRejected = errors.New("auth request rejected")
+
 // HandleBearerAuth validates the API key bearer token against the state layer.
 // A missing or malformed Authorization header is reported by ogen before this
 // is reached. Any validation failure — a malformed/unknown key (which
@@ -25,3 +29,59 @@ func (s *Server) HandleBearerAuth(
 
 	return ctx, nil
 }
+
+// AuthRegister registers a node via an auth id; it is an alias of RegisterNode.
+func (s *Server) AuthRegister(
+	ctx context.Context,
+	req *oas.AuthRegisterReq,
+) (*oas.AuthRegisterOK, error) {
+	resp, err := s.RegisterNode(ctx, oas.RegisterNodeParams{
+		Key:  oas.NewOptString(req.AuthId.Or("")),
+		User: oas.NewOptString(req.User.Or("")),
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return &oas.AuthRegisterOK{Node: resp.Node}, nil
+}
+
+// AuthApprove approves a pending auth session.
+func (s *Server) AuthApprove(_ context.Context, req *oas.AuthApproveReq) error {
+	authReq, apiErr := s.pendingAuth(req.AuthId.Or(""))
+	if apiErr != nil {
+		return apiErr
+	}
+
+	authReq.FinishAuth(types.AuthVerdict{})
+
+	return nil
+}
+
+// AuthReject rejects a pending auth session.
+func (s *Server) AuthReject(_ context.Context, req *oas.AuthRejectReq) error {
+	authReq, apiErr := s.pendingAuth(req.AuthId.Or(""))
+	if apiErr != nil {
+		return apiErr
+	}
+
+	authReq.FinishAuth(types.AuthVerdict{Err: errAuthRejected})
+
+	return nil
+}
+
+// pendingAuth resolves an auth id to its cached, in-progress auth request.
+// An unparseable id is a 400; an unknown one is a 404.
+func (s *Server) pendingAuth(authID string) (*types.AuthRequest, *oas.ErrorStatusCode) {
+	id, err := types.AuthIDFromString(authID)
+	if err != nil {
+		return nil, badRequest("invalid auth_id: " + err.Error())
+	}
+
+	authReq, ok := s.state.GetAuthCacheEntry(id)
+	if !ok {
+		return nil, notFound("no pending auth session for auth_id " + id.String())
+	}
+
+	return authReq, nil
+}

hscontrol/api/v1/policy.go

@@ -0,0 +1,112 @@
+package apiv1
+
+import (
+	"context"
+	"os"
+
+	oas "github.com/juanfont/headscale/gen/api/v1"
+	policyv2 "github.com/juanfont/headscale/hscontrol/policy/v2"
+	"github.com/juanfont/headscale/hscontrol/types"
+	"github.com/juanfont/headscale/hscontrol/util"
+)
+
+// GetPolicy returns the current ACL policy, from the database or the policy
+// file depending on the configured policy mode.
+func (s *Server) GetPolicy(_ context.Context) (*oas.GetPolicyOK, error) {
+	switch s.cfg.Policy.Mode {
+	case types.PolicyModeDB:
+		p, err := s.state.GetPolicy()
+		if err != nil {
+			return nil, internalError("loading ACL from database: " + err.Error())
+		}
+
+		return &oas.GetPolicyOK{
+			Policy:    oas.NewOptString(p.Data),
+			UpdatedAt: oas.NewOptDateTime(p.UpdatedAt),
+		}, nil
+	case types.PolicyModeFile:
+		absPath := util.AbsolutePathFromConfigPath(s.cfg.Policy.Path)
+
+		b, err := os.ReadFile(absPath)
+		if err != nil {
+			return nil, internalError("reading policy from path " + absPath + ": " + err.Error())
+		}
+
+		return &oas.GetPolicyOK{Policy: oas.NewOptString(string(b))}, nil
+	}
+
+	return nil, internalError(
+		"no supported policy mode found in configuration, policy.mode: " +
+			string(s.cfg.Policy.Mode),
+	)
+}
+
+// SetPolicy stores a new ACL policy (database policy mode only), validating it
+// against the live nodes and distributing the resulting changes.
+func (s *Server) SetPolicy(_ context.Context, req *oas.SetPolicyReq) (*oas.SetPolicyOK, error) {
+	if s.cfg.Policy.Mode != types.PolicyModeDB {
+		return nil, badRequest(types.ErrPolicyUpdateIsDisabled.Error())
+	}
+
+	p := req.Policy.Or("")
+
+	// Validate against live nodes, where they exist, before storing.
+	nodes := s.state.ListNodes()
+
+	_, err := s.state.SetPolicy([]byte(p))
+	if err != nil {
+		return nil, badRequest("setting policy: " + err.Error())
+	}
+
+	if nodes.Len() > 0 {
+		_, err = s.state.SSHPolicy(nodes.At(0))
+		if err != nil {
+			return nil, badRequest("verifying SSH rules: " + err.Error())
+		}
+	}
+
+	updated, err := s.state.SetPolicyInDB(p)
+	if err != nil {
+		return nil, mapStateError(err)
+	}
+
+	// Always reload so routes are re-evaluated even when the content is unchanged.
+	cs, err := s.state.ReloadPolicy()
+	if err != nil {
+		return nil, internalError("reloading policy: " + err.Error())
+	}
+
+	if len(cs) > 0 {
+		s.change(cs...)
+	}
+
+	return &oas.SetPolicyOK{
+		Policy:    oas.NewOptString(updated.Data),
+		UpdatedAt: oas.NewOptDateTime(updated.UpdatedAt),
+	}, nil
+}
+
+// CheckPolicy validates a policy against the live users and nodes without
+// storing it. Works regardless of policy mode.
+func (s *Server) CheckPolicy(_ context.Context, req *oas.CheckPolicyReq) error {
+	polB := []byte(req.Policy.Or(""))
+
+	users, err := s.state.ListAllUsers()
+	if err != nil {
+		return internalError("loading users: " + err.Error())
+	}
+
+	nodes := s.state.ListNodes()
+
+	pm, err := policyv2.NewPolicyManager(polB, users, nodes)
+	if err != nil {
+		return badRequest(err.Error())
+	}
+
+	_, err = pm.SetPolicy(polB)
+	if err != nil {
+		return badRequest(err.Error())
+	}
+
+	return nil
+}

hscontrol/servertest/apiv1_auth_test.go

@@ -0,0 +1,94 @@
+package servertest_test
+
+import (
+	"context"
+	"net/http"
+	"testing"
+
+	apiv1 "github.com/juanfont/headscale/gen/api/v1"
+	"github.com/juanfont/headscale/hscontrol/types"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAPIv1_AuthRegister_Errors(t *testing.T) {
+	srv, client := apiClient(t)
+	ctx := context.Background()
+
+	srv.CreateUser(t, "alice")
+
+	// Malformed auth id is a 400.
+	_, err := client.AuthRegister(ctx, &apiv1.AuthRegisterReq{
+		User:   apiv1.NewOptString("alice"),
+		AuthId: apiv1.NewOptString("not-valid"),
+	})
+	requireProblem(t, err, http.StatusBadRequest)
+}
+
+func TestAPIv1_AuthApprove(t *testing.T) {
+	srv, client := apiClient(t)
+	ctx := context.Background()
+
+	srv.CreateUser(t, "alice")
+
+	authID := types.MustAuthID()
+	_, err := client.DebugCreateNode(ctx, &apiv1.DebugCreateNodeReq{
+		User: apiv1.NewOptString("alice"),
+		Key:  apiv1.NewOptString(authID.String()),
+		Name: apiv1.NewOptString("pending-node"),
+	})
+	require.NoError(t, err)
+
+	authReq, ok := srv.State().GetAuthCacheEntry(authID)
+	require.True(t, ok)
+
+	// FinishAuth sends on an unbuffered channel; drain it so AuthApprove returns.
+	verdict := make(chan types.AuthVerdict, 1)
+	go func() { verdict <- <-authReq.WaitForAuth() }()
+
+	require.NoError(t, client.AuthApprove(ctx, &apiv1.AuthApproveReq{
+		AuthId: apiv1.NewOptString(authID.String()),
+	}))
+	assert.NoError(t, (<-verdict).Err, "approval verdict should carry no error")
+}
+
+func TestAPIv1_AuthReject(t *testing.T) {
+	srv, client := apiClient(t)
+	ctx := context.Background()
+
+	srv.CreateUser(t, "alice")
+
+	authID := types.MustAuthID()
+	_, err := client.DebugCreateNode(ctx, &apiv1.DebugCreateNodeReq{
+		User: apiv1.NewOptString("alice"),
+		Key:  apiv1.NewOptString(authID.String()),
+		Name: apiv1.NewOptString("pending-node"),
+	})
+	require.NoError(t, err)
+
+	authReq, ok := srv.State().GetAuthCacheEntry(authID)
+	require.True(t, ok)
+
+	verdict := make(chan types.AuthVerdict, 1)
+	go func() { verdict <- <-authReq.WaitForAuth() }()
+
+	require.NoError(t, client.AuthReject(ctx, &apiv1.AuthRejectReq{
+		AuthId: apiv1.NewOptString(authID.String()),
+	}))
+	assert.Error(t, (<-verdict).Err, "rejection verdict should carry an error")
+}
+
+func TestAPIv1_AuthApprove_Errors(t *testing.T) {
+	_, client := apiClient(t)
+	ctx := context.Background()
+
+	// Malformed auth id is a 400.
+	requireProblem(t, client.AuthApprove(ctx, &apiv1.AuthApproveReq{
+		AuthId: apiv1.NewOptString("not-valid"),
+	}), http.StatusBadRequest)
+
+	// Unknown (but well-formed) auth id is a 404.
+	requireProblem(t, client.AuthApprove(ctx, &apiv1.AuthApproveReq{
+		AuthId: apiv1.NewOptString(types.MustAuthID().String()),
+	}), http.StatusNotFound)
+}

hscontrol/servertest/apiv1_policy_test.go

@@ -0,0 +1,42 @@
+package servertest_test
+
+import (
+	"context"
+	"net/http"
+	"testing"
+
+	apiv1 "github.com/juanfont/headscale/gen/api/v1"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+const validPolicy = `{"acls":[{"action":"accept","src":["*"],"dst":["*:*"]}]}`
+
+func TestAPIv1_SetAndGetPolicy(t *testing.T) {
+	_, client := apiClient(t)
+	ctx := context.Background()
+
+	setResp, err := client.SetPolicy(ctx, &apiv1.SetPolicyReq{
+		Policy: apiv1.NewOptString(validPolicy),
+	})
+	require.NoError(t, err)
+	require.NotEmpty(t, setResp.Policy.Value)
+
+	getResp, err := client.GetPolicy(ctx)
+	require.NoError(t, err)
+	assert.Equal(t, setResp.Policy.Value, getResp.Policy.Value)
+}
+
+func TestAPIv1_CheckPolicy(t *testing.T) {
+	_, client := apiClient(t)
+	ctx := context.Background()
+
+	require.NoError(t, client.CheckPolicy(ctx, &apiv1.CheckPolicyReq{
+		Policy: apiv1.NewOptString(validPolicy),
+	}))
+
+	// Invalid policy is a 400.
+	requireProblem(t, client.CheckPolicy(ctx, &apiv1.CheckPolicyReq{
+		Policy: apiv1.NewOptString("{not valid"),
+	}), http.StatusBadRequest)
+}