caddy/modules/caddypki/adminapi.go

250 lines
7.0 KiB
Go

// Copyright 2020 Matthew Holt and The Caddy Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package caddypki
import (
"encoding/json"
"fmt"
"net/http"
"strings"
"go.uber.org/zap"
"github.com/caddyserver/caddy/v2"
)
func init() {
caddy.RegisterModule(adminAPI{})
}
// adminAPI is a module that serves PKI endpoints to retrieve
// information about the CAs being managed by Caddy.
type adminAPI struct {
ctx caddy.Context
log *zap.Logger
pkiApp *PKI
}
// CaddyModule returns the Caddy module information.
func (adminAPI) CaddyModule() caddy.ModuleInfo {
return caddy.ModuleInfo{
ID: "admin.api.pki",
New: func() caddy.Module { return new(adminAPI) },
}
}
// Provision sets up the adminAPI module.
func (a *adminAPI) Provision(ctx caddy.Context) error {
a.ctx = ctx
a.log = ctx.Logger(a) // TODO: passing in 'a' is a hack until the admin API is officially extensible (see #5032)
// Avoid initializing PKI if it wasn't configured.
// We intentionally ignore the error since it's not
// fatal if the PKI app is not explicitly configured.
pkiApp, err := ctx.AppIfConfigured("pki")
if err == nil {
a.pkiApp = pkiApp.(*PKI)
}
return nil
}
// Routes returns the admin routes for the PKI app.
func (a *adminAPI) Routes() []caddy.AdminRoute {
return []caddy.AdminRoute{
{
Pattern: adminPKIEndpointBase,
Handler: caddy.AdminHandlerFunc(a.handleAPIEndpoints),
},
}
}
// handleAPIEndpoints routes API requests within adminPKIEndpointBase.
func (a *adminAPI) handleAPIEndpoints(w http.ResponseWriter, r *http.Request) error {
uri := strings.TrimPrefix(r.URL.Path, "/pki/")
parts := strings.Split(uri, "/")
switch {
case len(parts) == 2 && parts[0] == "ca" && parts[1] != "":
return a.handleCAInfo(w, r)
case len(parts) == 3 && parts[0] == "ca" && parts[1] != "" && parts[2] == "certificates":
return a.handleCACerts(w, r)
}
return caddy.APIError{
HTTPStatus: http.StatusNotFound,
Err: fmt.Errorf("resource not found: %v", r.URL.Path),
}
}
// handleCAInfo returns information about a particular
// CA by its ID. If the CA ID is the default, then the CA will be
// provisioned if it has not already been. Other CA IDs will return an
// error if they have not been previously provisioned.
func (a *adminAPI) handleCAInfo(w http.ResponseWriter, r *http.Request) error {
if r.Method != http.MethodGet {
return caddy.APIError{
HTTPStatus: http.StatusMethodNotAllowed,
Err: fmt.Errorf("method not allowed: %v", r.Method),
}
}
ca, err := a.getCAFromAPIRequestPath(r)
if err != nil {
return err
}
rootCert, interCert, err := rootAndIntermediatePEM(ca)
if err != nil {
return caddy.APIError{
HTTPStatus: http.StatusInternalServerError,
Err: fmt.Errorf("failed to get root and intermediate cert for CA %s: %v", ca.ID, err),
}
}
repl := ca.newReplacer()
response := caInfo{
ID: ca.ID,
Name: ca.Name,
RootCN: repl.ReplaceAll(ca.RootCommonName, ""),
IntermediateCN: repl.ReplaceAll(ca.IntermediateCommonName, ""),
RootCert: string(rootCert),
IntermediateCert: string(interCert),
}
encoded, err := json.Marshal(response)
if err != nil {
return caddy.APIError{
HTTPStatus: http.StatusInternalServerError,
Err: err,
}
}
w.Header().Set("Content-Type", "application/json")
_, _ = w.Write(encoded)
return nil
}
// handleCACerts returns the certificate chain for a particular
// CA by its ID. If the CA ID is the default, then the CA will be
// provisioned if it has not already been. Other CA IDs will return an
// error if they have not been previously provisioned.
func (a *adminAPI) handleCACerts(w http.ResponseWriter, r *http.Request) error {
if r.Method != http.MethodGet {
return caddy.APIError{
HTTPStatus: http.StatusMethodNotAllowed,
Err: fmt.Errorf("method not allowed: %v", r.Method),
}
}
ca, err := a.getCAFromAPIRequestPath(r)
if err != nil {
return err
}
rootCert, interCert, err := rootAndIntermediatePEM(ca)
if err != nil {
return caddy.APIError{
HTTPStatus: http.StatusInternalServerError,
Err: fmt.Errorf("failed to get root and intermediate cert for CA %s: %v", ca.ID, err),
}
}
w.Header().Set("Content-Type", "application/pem-certificate-chain")
_, err = w.Write(interCert)
if err == nil {
_, _ = w.Write(rootCert)
}
return nil
}
func (a *adminAPI) getCAFromAPIRequestPath(r *http.Request) (*CA, error) {
// Grab the CA ID from the request path, it should be the 4th segment (/pki/ca/<ca>)
id := strings.Split(r.URL.Path, "/")[3]
if id == "" {
return nil, caddy.APIError{
HTTPStatus: http.StatusBadRequest,
Err: fmt.Errorf("missing CA in path"),
}
}
// Find the CA by ID, if PKI is configured
var ca *CA
var ok bool
if a.pkiApp != nil {
ca, ok = a.pkiApp.CAs[id]
}
// If we didn't find the CA, and PKI is not configured
// then we'll either error out if the CA ID is not the
// default. If the CA ID is the default, then we'll
// provision it, because the user probably aims to
// change their config to enable PKI immediately after
// if they actually requested the local CA ID.
if !ok {
if id != DefaultCAID {
return nil, caddy.APIError{
HTTPStatus: http.StatusNotFound,
Err: fmt.Errorf("no certificate authority configured with id: %s", id),
}
}
// Provision the default CA, which generates and stores a root
// certificate in storage, if one doesn't already exist.
ca = new(CA)
err := ca.Provision(a.ctx, id, a.log)
if err != nil {
return nil, caddy.APIError{
HTTPStatus: http.StatusInternalServerError,
Err: fmt.Errorf("failed to provision CA %s, %w", id, err),
}
}
}
return ca, nil
}
func rootAndIntermediatePEM(ca *CA) (root, inter []byte, err error) {
root, err = pemEncodeCert(ca.RootCertificate().Raw)
if err != nil {
return
}
inter, err = pemEncodeCert(ca.IntermediateCertificate().Raw)
if err != nil {
return
}
return
}
// caInfo is the response structure for the CA info API endpoint.
type caInfo struct {
ID string `json:"id"`
Name string `json:"name"`
RootCN string `json:"root_common_name"`
IntermediateCN string `json:"intermediate_common_name"`
RootCert string `json:"root_certificate"`
IntermediateCert string `json:"intermediate_certificate"`
}
// adminPKIEndpointBase is the base admin endpoint under which all PKI admin endpoints exist.
const adminPKIEndpointBase = "/pki/"
// Interface guards
var (
_ caddy.AdminRouter = (*adminAPI)(nil)
_ caddy.Provisioner = (*adminAPI)(nil)
)