1 files changed, 194 insertions, 0 deletions
diff --git a/modules/caddypki/adminpki.go b/modules/caddypki/adminpki.go
new file mode 100644
index 0000000..5933bcd
--- /dev/null
+++ b/modules/caddypki/adminpki.go
@@ -0,0 +1,194 @@
+// 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"
+	"encoding/pem"
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/caddyserver/caddy/v2"
+	"go.uber.org/zap"
+)
+
+func init() {
+	caddy.RegisterModule(adminPKI{})
+}
+
+// adminPKI is a module that serves a PKI endpoint to retrieve
+// information about the CAs being managed by Caddy.
+type adminPKI struct {
+	ctx    caddy.Context
+	log    *zap.Logger
+	pkiApp *PKI
+}
+
+// CaddyModule returns the Caddy module information.
+func (adminPKI) CaddyModule() caddy.ModuleInfo {
+	return caddy.ModuleInfo{
+		ID:  "admin.api.pki",
+		New: func() caddy.Module { return new(adminPKI) },
+	}
+}
+
+// Provision sets up the adminPKI module.
+func (a *adminPKI) Provision(ctx caddy.Context) error {
+	a.ctx = ctx
+	a.log = ctx.Logger(a)
+
+	// First check if the PKI app was configured, because
+	// a.ctx.App() has the side effect of instantiating
+	// and provisioning an app even if it wasn't configured.
+	pkiAppConfigured := a.ctx.AppIsConfigured("pki")
+	if !pkiAppConfigured {
+		return nil
+	}
+
+	// Load the PKI app, so we can query it for information.
+	appModule, err := a.ctx.App("pki")
+	if err != nil {
+		return err
+	}
+	a.pkiApp = appModule.(*PKI)
+
+	return nil
+}
+
+// Routes returns the admin routes for the PKI app.
+func (a *adminPKI) Routes() []caddy.AdminRoute {
+	return []caddy.AdminRoute{
+		{
+			Pattern: adminPKICertificatesEndpoint,
+			Handler: caddy.AdminHandlerFunc(a.handleCertificates),
+		},
+	}
+}
+
+// handleCertificates returns certificate 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 *adminPKI) handleCertificates(w http.ResponseWriter, r *http.Request) error {
+	if r.Method != http.MethodGet {
+		return caddy.APIError{
+			HTTPStatus: http.StatusMethodNotAllowed,
+			Err:        fmt.Errorf("method not allowed"),
+		}
+	}
+
+	// Prep for a JSON response
+	w.Header().Set("Content-Type", "application/json")
+	enc := json.NewEncoder(w)
+
+	idPath := r.URL.Path
+
+	// Grab the CA ID from the request path, it should be the 4th segment
+	parts := strings.Split(idPath, "/")
+	if len(parts) < 4 || parts[3] == "" {
+		return caddy.APIError{
+			HTTPStatus: http.StatusBadRequest,
+			Err:        fmt.Errorf("request path is missing the CA ID"),
+		}
+	}
+	if parts[0] != "" || parts[1] != "pki" || parts[2] != "certificates" {
+		return caddy.APIError{
+			HTTPStatus: http.StatusBadRequest,
+			Err:        fmt.Errorf("malformed object path"),
+		}
+	}
+	id := parts[3]
+
+	// Find the CA by ID, if PKI is configured
+	var ca *CA
+	ok := false
+	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 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 caddy.APIError{
+				HTTPStatus: http.StatusInternalServerError,
+				Err:        fmt.Errorf("failed to provision CA %s, %w", id, err),
+			}
+		}
+	}
+
+	// Convert the root certificate to PEM
+	rootPem := string(pem.EncodeToMemory(&pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: ca.RootCertificate().Raw,
+	}))
+
+	// Convert the intermediate certificate to PEM
+	interPem := string(pem.EncodeToMemory(&pem.Block{
+		Type:  "CERTIFICATE",
+		Bytes: ca.IntermediateCertificate().Raw,
+	}))
+
+	// Build the response
+	response := CAInfo{
+		ID:           ca.ID,
+		Name:         ca.Name,
+		Root:         rootPem,
+		Intermediate: interPem,
+	}
+
+	// Encode and write the JSON response
+	err := enc.Encode(response)
+	if err != nil {
+		return caddy.APIError{
+			HTTPStatus: http.StatusInternalServerError,
+			Err:        err,
+		}
+	}
+
+	return nil
+}
+
+// CAInfo is the response from the certificates API endpoint
+type CAInfo struct {
+	ID           string `json:"id"`
+	Name         string `json:"name"`
+	Root         string `json:"root"`
+	Intermediate string `json:"intermediate"`
+}
+
+const adminPKICertificatesEndpoint = "/pki/certificates/"
+
+// Interface guards
+var (
+	_ caddy.AdminRouter = (*adminPKI)(nil)
+	_ caddy.Provisioner = (*adminPKI)(nil)
+)