lego/acme/client.go

144 lines
3.3 KiB
Go

package acme
import (
"bytes"
"crypto/rsa"
"encoding/json"
"errors"
"io/ioutil"
"log"
"net/http"
"os"
"regexp"
"strings"
"github.com/square/go-jose"
)
// Logger is used to log errors; if nil, the default log.Logger is used.
var Logger *log.Logger
// logger is an helper function to retrieve the available logger
func logger() *log.Logger {
if Logger == nil {
Logger = log.New(os.Stderr, "", log.LstdFlags)
}
return Logger
}
// User interface is to be implemented by users of this library.
// It is used by the client type to get user specific information.
type User interface {
GetEmail() string
GetRegistration() *RegistrationResource
GetPrivateKey() *rsa.PrivateKey
}
// Client is the user-friendy way to ACME
type Client struct {
regURL string
user User
}
// NewClient creates a new client for the set user.
func NewClient(caURL string, usr User) *Client {
if err := usr.GetPrivateKey().Validate(); err != nil {
logger().Fatalf("Could not validate the private account key of %s -> %v", usr.GetEmail(), err)
}
return &Client{regURL: caURL, user: usr}
}
// Posts a JWS signed message to the specified URL
func (c *Client) jwsPost(url string, content []byte) (*http.Response, error) {
signer, err := jose.NewSigner(jose.RS256, c.user.GetPrivateKey())
if err != nil {
return nil, err
}
signed, err := signer.Sign(content)
if err != nil {
return nil, err
}
signedContent := signed.FullSerialize()
resp, err := http.Post(url, "application/json", bytes.NewBuffer([]byte(signedContent)))
if err != nil {
return nil, err
}
return resp, err
}
// Register the current account to the ACME server.
func (c *Client) Register() (*RegistrationResource, error) {
logger().Print("Registering account ... ")
jsonBytes, err := json.Marshal(registrationMessage{Contact: []string{"mailto:" + c.user.GetEmail()}})
if err != nil {
return nil, err
}
resp, err := c.jwsPost(c.regURL, jsonBytes)
if err != nil {
return nil, err
}
if resp.StatusCode == http.StatusConflict {
// REVIEW: should this return an error?
return nil, errors.New("This account is already registered with this CA.")
}
var serverReg Registration
decoder := json.NewDecoder(resp.Body)
err = decoder.Decode(&serverReg)
if err != nil {
return nil, err
}
reg := &RegistrationResource{Body: serverReg}
links := parseLinks(resp.Header["Link"])
reg.URI = resp.Header.Get("Location")
if links["terms-of-service"] != "" {
reg.TosURL = links["terms-of-service"]
}
if links["next"] != "" {
reg.NewAuthzURL = links["next"]
} else {
return nil, errors.New("The server did not return enough information to proceed...")
}
return reg, nil
}
func logResponseHeaders(resp *http.Response) {
logger().Println(resp.Status)
for k, v := range resp.Header {
logger().Printf("-- %s: %s", k, v)
}
}
func logResponseBody(resp *http.Response) {
body, _ := ioutil.ReadAll(resp.Body)
logger().Printf("Returned json data: \n%s", body)
}
func parseLinks(links []string) map[string]string {
aBrkt := regexp.MustCompile("[<>]")
slver := regexp.MustCompile("(.+) *= *\"(.+)\"")
linkMap := make(map[string]string)
for _, link := range links {
link = aBrkt.ReplaceAllString(link, "")
parts := strings.Split(link, ";")
matches := slver.FindStringSubmatch(parts[1])
if len(matches) > 0 {
linkMap[matches[2]] = parts[0]
}
}
return linkMap
}