lego/providers/dns/nearlyfreespeech/internal/client.go
2023-08-21 00:25:40 +02:00

143 lines
3.3 KiB
Go

package internal
import (
"context"
"crypto/sha1"
"encoding/json"
"fmt"
"io"
"math/rand"
"net/http"
"net/url"
"strconv"
"strings"
"time"
"github.com/go-acme/lego/v4/challenge/dns01"
"github.com/go-acme/lego/v4/providers/dns/internal/errutils"
querystring "github.com/google/go-querystring/query"
)
const apiURL = "https://api.nearlyfreespeech.net"
const authenticationHeader = "X-NFSN-Authentication"
const saltBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
type Client struct {
login string
apiKey string
signer *Signer
baseURL *url.URL
HTTPClient *http.Client
}
func NewClient(login string, apiKey string) *Client {
baseURL, _ := url.Parse(apiURL)
return &Client{
login: login,
apiKey: apiKey,
signer: NewSigner(),
baseURL: baseURL,
HTTPClient: &http.Client{Timeout: 10 * time.Second},
}
}
func (c Client) AddRecord(ctx context.Context, domain string, record Record) error {
endpoint := c.baseURL.JoinPath("dns", dns01.UnFqdn(domain), "addRR")
params, err := querystring.Values(record)
if err != nil {
return err
}
return c.doRequest(ctx, endpoint, params)
}
func (c Client) RemoveRecord(ctx context.Context, domain string, record Record) error {
endpoint := c.baseURL.JoinPath("dns", dns01.UnFqdn(domain), "removeRR")
params, err := querystring.Values(record)
if err != nil {
return err
}
return c.doRequest(ctx, endpoint, params)
}
func (c Client) doRequest(ctx context.Context, endpoint *url.URL, params url.Values) error {
payload := params.Encode()
req, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint.String(), strings.NewReader(payload))
if err != nil {
return fmt.Errorf("unable to create request: %w", err)
}
req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
req.Header.Set(authenticationHeader, c.signer.Sign(endpoint.Path, payload, c.login, c.apiKey))
resp, err := c.HTTPClient.Do(req)
if err != nil {
return errutils.NewHTTPDoError(req, err)
}
defer func() { _ = resp.Body.Close() }()
if resp.StatusCode != http.StatusOK {
return parseError(req, resp)
}
return nil
}
func parseError(req *http.Request, resp *http.Response) error {
raw, _ := io.ReadAll(resp.Body)
errAPI := &APIError{}
err := json.Unmarshal(raw, errAPI)
if err != nil {
return errutils.NewUnexpectedStatusCodeError(req, resp.StatusCode, raw)
}
return errAPI
}
type Signer struct {
saltShaker func() []byte
clock func() time.Time
}
func NewSigner() *Signer {
return &Signer{saltShaker: getRandomSalt, clock: time.Now}
}
func (c Signer) Sign(uri string, body, login, apiKey string) string {
// Header is "login;timestamp;salt;hash".
// hash is SHA1("login;timestamp;salt;api-key;request-uri;body-hash")
// and body-hash is SHA1(body).
bodyHash := sha1.Sum([]byte(body))
timestamp := strconv.FormatInt(c.clock().Unix(), 10)
// Workaround for https://golang.org/issue/58605
uri = "/" + strings.TrimLeft(uri, "/")
salt := c.saltShaker()
hashInput := fmt.Sprintf("%s;%s;%s;%s;%s;%02x", login, timestamp, salt, apiKey, uri, bodyHash)
return fmt.Sprintf("%s;%s;%s;%02x", login, timestamp, salt, sha1.Sum([]byte(hashInput)))
}
func getRandomSalt() []byte {
// This is the only part of this that needs to be serialized.
salt := make([]byte, 16)
for i := 0; i < 16; i++ {
salt[i] = saltBytes[rand.Intn(len(saltBytes))]
}
return salt
}