optimize-server-for-all-zero-nonce-case.patch

Signed-off-by: Andy Green <andy.green@linaro.org>

diff --git a/lib/parsers.c b/lib/parsers.c
index a785438..bb0963f 100644 (file)
--- a/lib/parsers.c
+++ b/lib/parsers.c
@@ -267,7 +267,10 @@ static int libwebsocket_rx_sm(struct libwebsocket *wsi, unsigned char c)
                        break;
                case 4:
                case 5:
+                       wsi->all_zero_nonce = 1;
                        wsi->frame_masking_nonce_04[0] = c;
+                       if (c)
+                               wsi->all_zero_nonce = 0;
                        wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_1;
                        break;
                default:
@@ -278,14 +281,20 @@ static int libwebsocket_rx_sm(struct libwebsocket *wsi, unsigned char c)
                break;
        case LWS_RXPS_04_MASK_NONCE_1:
                wsi->frame_masking_nonce_04[1] = c;
+               if (c)
+                       wsi->all_zero_nonce = 0;
                wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_2;
                break;
        case LWS_RXPS_04_MASK_NONCE_2:
                wsi->frame_masking_nonce_04[2] = c;
+               if (c)
+                       wsi->all_zero_nonce = 0;
                wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_3;
                break;
        case LWS_RXPS_04_MASK_NONCE_3:
                wsi->frame_masking_nonce_04[3] = c;
+               if (c)
+                       wsi->all_zero_nonce = 0;
 
                if (wsi->protocol->owning_server->options &
                                           LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK)
@@ -561,7 +570,11 @@ issue:
                break;
 
        case LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED:
-               wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
+               if (wsi->all_zero_nonce && wsi->ietf_spec_revision >= 5)
+                       wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
+                              (wsi->rx_user_buffer_head++)] = c;
+               else
+                       wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
                               (wsi->rx_user_buffer_head++)] =
                                                          wsi->xor_mask(wsi, c);
 
@@ -1226,13 +1239,22 @@ int libwebsocket_write(struct libwebsocket *wsi, unsigned char *buf,
 
                        for (n = 0; n < (len + pre + post); n++)
                                buf[n - pre] = wsi->xor_mask(wsi, buf[n - pre]);
-               }
 
-               /* make space for the frame nonce in clear */
-               pre += 4;
 
-               /* copy the frame nonce into place */
-               memcpy(&buf[0 - pre], wsi->frame_masking_nonce_04, 4);
+                       /* make space for the frame nonce in clear */
+                       pre += 4;
+
+                       /* copy the frame nonce into place */
+                       memcpy(&buf[0 - pre], wsi->frame_masking_nonce_04, 4);
+               } else {
+                       /* make space for the frame nonce in clear */
+                       pre += 4;
+
+                       buf[0 - pre] = 0;
+                       buf[1 - pre] = 0;
+                       buf[2 - pre] = 0;
+                       buf[3 - pre] = 0;
+               }
 
        }
 

diff --git a/lib/private-libwebsockets.h b/lib/private-libwebsockets.h
index 71241e7..a164252 100644 (file)
--- a/lib/private-libwebsockets.h
+++ b/lib/private-libwebsockets.h
@@ -229,6 +229,7 @@ struct libwebsocket {
 
        int pings_vs_pongs;
        unsigned char (*xor_mask)(struct libwebsocket *, unsigned char);
+       char all_zero_nonce;
 
        /* client support */
        char initial_handshake_hash_base64[30];