traefik/pkg/middlewares/auth/digest_auth_request_test.go
Ludovic Fernandez f1b085fa36 Move code to pkg
2019-03-15 09:42:03 +01:00

141 lines
3 KiB
Go

package auth
import (
"crypto/md5"
"crypto/rand"
"encoding/hex"
"fmt"
"io"
"net/http"
"strings"
)
const (
algorithm = "algorithm"
authorization = "Authorization"
nonce = "nonce"
opaque = "opaque"
qop = "qop"
realm = "realm"
wwwAuthenticate = "Www-Authenticate"
)
// DigestRequest is a client for digest authentication requests
type digestRequest struct {
client *http.Client
username, password string
nonceCount nonceCount
}
type nonceCount int
func (nc nonceCount) String() string {
return fmt.Sprintf("%08x", int(nc))
}
var wanted = []string{algorithm, nonce, opaque, qop, realm}
// New makes a DigestRequest instance
func newDigestRequest(username, password string, client *http.Client) *digestRequest {
return &digestRequest{
client: client,
username: username,
password: password,
}
}
// Do does requests as http.Do does
func (r *digestRequest) Do(req *http.Request) (*http.Response, error) {
parts, err := r.makeParts(req)
if err != nil {
return nil, err
}
if parts != nil {
req.Header.Set(authorization, r.makeAuthorization(req, parts))
}
return r.client.Do(req)
}
func (r *digestRequest) makeParts(req *http.Request) (map[string]string, error) {
authReq, err := http.NewRequest(req.Method, req.URL.String(), nil)
if err != nil {
return nil, err
}
resp, err := r.client.Do(authReq)
if err != nil {
return nil, err
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusUnauthorized {
return nil, nil
}
if len(resp.Header[wwwAuthenticate]) == 0 {
return nil, fmt.Errorf("headers do not have %s", wwwAuthenticate)
}
headers := strings.Split(resp.Header[wwwAuthenticate][0], ",")
parts := make(map[string]string, len(wanted))
for _, r := range headers {
for _, w := range wanted {
if strings.Contains(r, w) {
parts[w] = strings.Split(r, `"`)[1]
}
}
}
if len(parts) != len(wanted) {
return nil, fmt.Errorf("header is invalid: %+v", parts)
}
return parts, nil
}
func getMD5(texts []string) string {
h := md5.New()
_, _ = io.WriteString(h, strings.Join(texts, ":"))
return hex.EncodeToString(h.Sum(nil))
}
func (r *digestRequest) getNonceCount() string {
r.nonceCount++
return r.nonceCount.String()
}
func (r *digestRequest) makeAuthorization(req *http.Request, parts map[string]string) string {
ha1 := getMD5([]string{r.username, parts[realm], r.password})
ha2 := getMD5([]string{req.Method, req.URL.String()})
cnonce := generateRandom(16)
nc := r.getNonceCount()
response := getMD5([]string{
ha1,
parts[nonce],
nc,
cnonce,
parts[qop],
ha2,
})
return fmt.Sprintf(
`Digest username="%s", realm="%s", nonce="%s", uri="%s", algorithm=%s, qop=%s, nc=%s, cnonce="%s", response="%s", opaque="%s"`,
r.username,
parts[realm],
parts[nonce],
req.URL.String(),
parts[algorithm],
parts[qop],
nc,
cnonce,
response,
parts[opaque],
)
}
// GenerateRandom generates random string
func generateRandom(n int) string {
b := make([]byte, 8)
_, _ = io.ReadFull(rand.Reader, b)
return fmt.Sprintf("%x", b)[:n]
}