cacert-gosigner/pkg/messages/messages.go

/*
Copyright 2022 CAcert Inc.
SPDX-License-Identifier: Apache-2.0

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.
*/

//go:generate go run github.com/shamaton/msgpackgen

// Package messages contains structure definitions for protocol messages
package messages

import (
	"crypto/x509"
	"encoding/pem"
	"fmt"
	"strings"
	"time"
)

type CommandCode int8

const (
	CmdHealth CommandCode = iota
	CmdFetchCRL
)

var commandNames = map[CommandCode]string{
	CmdHealth:   "HEALTH",
	CmdFetchCRL: "FETCH URL",
}

func (c CommandCode) String() string {
	if name, ok := commandNames[c]; ok {
		return name
	}

	return fmt.Sprintf("unknown %d", c)
}

type ResponseCode int8

const (
	RespError  ResponseCode = -1
	RespHealth ResponseCode = iota
	RespFetchCRL
)

var responseNames = map[ResponseCode]string{
	RespError:    "ERROR",
	RespHealth:   "HEALTH",
	RespFetchCRL: "FETCH CRL",
}

func (c ResponseCode) String() string {
	if name, ok := responseNames[c]; ok {
		return name
	}

	return fmt.Sprintf("unknown %d", c)
}

type CommandAnnounce struct {
	Code    CommandCode `msgpack:"code"`
	Created time.Time   `msgpack:"created"`
}

func (r *CommandAnnounce) String() string {
	return fmt.Sprintf("CommandAnnounce[code=%s, created=%s]", r.Code, r.Created)
}

type ResponseAnnounce struct {
	Code    ResponseCode `msgpack:"code"`
	Created time.Time    `msgpack:"created"`
}

func (r *ResponseAnnounce) String() string {
	return fmt.Sprintf("ResponseAnnounce[code=%s, created=%s]", r.Code, r.Created)
}

type FetchCRLCommand struct {
	IssuerID      string `msgpack:"issuer_id"`
	LastKnownHash struct {
		Algorithm string `msgpack:"algorithm"`
		Value     string `msgpack:"value"`
	} `msgpack:"last_known_hash"` // optional last known hash in format
}

type HealthCommand struct {
}

type HealthInfo struct {
	Source   string
	Healthy  bool
	MoreInfo map[string]string
}

func (i *HealthInfo) String() string {
	builder := &strings.Builder{}

	_, _ = fmt.Fprintf(builder, "source: %s, healthy: %v, [\n", i.Source, i.Healthy)

	for k, v := range i.MoreInfo {
		_, _ = fmt.Fprintf(builder, "  %s: '%s'\n", k, v)
	}

	_, _ = builder.WriteRune(']')

	return builder.String()
}

type HealthResponse struct {
	Version string `msgpack:"version"`
	Healthy bool   `msgpack:"healthy"`
	Info    []*HealthInfo
}

func (h *HealthResponse) String() string {
	builder := &strings.Builder{}

	_, _ = fmt.Fprintf(builder, "signer version=%s, healthy=%v, health data:\n", h.Version, h.Healthy)

	for _, info := range h.Info {
		_, _ = fmt.Fprintf(builder, " - %s", info)
	}

	return builder.String()
}

type FetchCRLResponse struct {
	IssuerID string `msgpack:"issuer_id"`
	IsDelta  bool   `msgpack:"is_delta"`
	CRLData  []byte `msgpack:"crl_data"`
}

func (r *FetchCRLResponse) String() string {
	builder := &strings.Builder{}

	_, _ = fmt.Fprintf(builder, "issuer id=%s, delta CRL data=%v", r.IssuerID, r.IsDelta)

	if r.IsDelta {
		_, _ = fmt.Fprint(builder, ", delta CRL data not shown")
	} else {
		revlist, err := x509.ParseRevocationList(r.CRLData)
		if err != nil {
			_, _ = fmt.Fprintf(builder, ", could not parse CRL: %s", err.Error())
		} else {
			_, _ = fmt.Fprintf(builder, ", CRL info: issuer=%s, number=%s, next update=%s, revoked certificates=%d",
				revlist.Issuer, revlist.Number, revlist.NextUpdate, len(revlist.RevokedCertificates))
			_, _ = builder.WriteString(", CRL data:\n")
			_ = pem.Encode(builder, &pem.Block{
				Type:  "CERTIFICATE REVOCATION LIST",
				Bytes: r.CRLData,
			})
		}
	}

	return builder.String()
}

type ErrorResponse struct {
	Message string `msgpack:"message"`
}

func BuildCommandAnnounce(code CommandCode) *CommandAnnounce {
	return &CommandAnnounce{Code: code, Created: time.Now().UTC()}
}

func BuildResponseAnnounce(code ResponseCode) *ResponseAnnounce {
	return &ResponseAnnounce{Code: code, Created: time.Now().UTC()}
}