RC-6

cmd/client/api.go

@@ -117,10 +117,38 @@ func (c *apiClient) do(ctx context.Context, method, path string, body, out any)
 	return nil
 }
 
+func leadingZeroBitsClient(b []byte) int {
+	n := 0
+	for _, x := range b {
+		if x == 0 {
+			n += 8
+			continue
+		}
+		for m := byte(0x80); m != 0 && x&m == 0; m >>= 1 {
+			n++
+		}
+		break
+	}
+	return n
+}
+
+func solveProofClient(challenge, cid string, bits int) string {
+	if bits <= 0 {
+		return ""
+	}
+	for i := uint64(0); ; i++ {
+		counter := strconv.FormatUint(i, 10)
+		h := sha256.Sum256([]byte("nh-pow-v1|" + challenge + "|" + cid + "|" + counter))
+		if leadingZeroBitsClient(h[:]) >= bits {
+			return counter
+		}
+	}
+}
 func (c *apiClient) login(ctx context.Context) error {
 	var ch struct {
-		ClientID  string `json:"client_id"`
-		Challenge string `json:"challenge"`
+		ClientID        string `json:"client_id"`
+		Challenge       string `json:"challenge"`
+		ProofOfWorkBits int    `json:"proof_of_work_bits"`
 	}
 	if err := c.do(ctx, http.MethodPost, "/api/auth/challenge", map[string]any{"public_jwk": c.id.PublicJWK}, &ch); err != nil {
 		return fmt.Errorf("challenge: %w", err)
@@ -133,10 +161,12 @@ func (c *apiClient) login(ctx context.Context) error {
 		Token    string `json:"token"`
 		ClientID string `json:"client_id"`
 	}
+	pow := solveProofClient(ch.Challenge, ch.ClientID, ch.ProofOfWorkBits)
 	if err := c.do(ctx, http.MethodPost, "/api/auth/login", map[string]any{
-		"public_jwk": c.id.PublicJWK,
-		"challenge":  ch.Challenge,
-		"signature":  sig,
+		"public_jwk":            c.id.PublicJWK,
+		"challenge":             ch.Challenge,
+		"signature":             sig,
+		"proof_of_work_counter": pow,
 	}, &lg); err != nil {
 		return fmt.Errorf("login: %w", err)
 	}
@@ -276,10 +306,11 @@ func (c *apiClient) dialWS(ctx context.Context, maxNodes int) (*websocket.Conn,
 		scheme = "wss"
 	}
 	q := url.Values{}
-	q.Set("token", c.token)
 	q.Set("max_nodes", strconv.Itoa(maxNodes))
 	wu := scheme + "://" + u.Host + "/api/ws?" + q.Encode()
-	conn, resp, err := websocket.DefaultDialer.DialContext(ctx, wu, nil)
+	h := http.Header{}
+	h.Set("Authorization", "Bearer "+c.token)
+	conn, resp, err := websocket.DefaultDialer.DialContext(ctx, wu, h)
 	if err != nil && resp != nil {
 		b, _ := io.ReadAll(io.LimitReader(resp.Body, 4096))
 		_ = resp.Body.Close()