Release 2.18.1

- [FEATURE] Implement the "QUIC bit grease" extension.
- [BUGFIX] Selecting CID used for logging on client.
- [BUGFIX] Header protection assertion.
- [BUGFIX] Server: enable SSL key logging when cert lookup callback
  is not set.
- Remove some dead code.

CHANGELOG

@@ -1,3 +1,12 @@
+2020-07-14
+    - 2.18.1
+    - [FEATURE] Implement the "QUIC bit grease" extension.
+    - [BUGFIX] Selecting CID used for logging on client.
+    - [BUGFIX] Header protection assertion.
+    - [BUGFIX] Server: enable SSL key logging when cert lookup callback
+      is not set.
+    - Remove some dead code.
+
 2020-07-06
     - 2.18.0
     - [API] Rename "0-RTT" to "session resumption." In IETF QUIC, "0-RTT"

bin/test_common.c

@@ -1920,6 +1920,11 @@ set_engine_option (struct lsquic_engine_settings *settings,
             settings->es_allow_migration = atoi(val);
             return 0;
         }
+        if (0 == strncmp(name, "grease_quic_bit", 15))
+        {
+            settings->es_grease_quic_bit = atoi(val);
+            return 0;
+        }
         break;
     case 16:
         if (0 == strncmp(name, "proc_time_thresh", 16))

docs/apiref.rst

@@ -752,6 +752,14 @@ settings structure:
        Default value is :macro:`LSQUIC_DF_NOPROGRESS_TIMEOUT_SERVER` in server
        mode and :macro:`LSQUIC_DF_NOPROGRESS_TIMEOUT_CLIENT` in client mode.
 
+    .. member:: int             es_grease_quic_bit
+
+       Enable the "QUIC bit grease" extension.  When set to a true value,
+       lsquic will grease the QUIC bit on the outgoing QUIC packets if
+       the peer sent the "grease_quic_bit" transport parameter.
+
+       Default value is :macro:`LSQUIC_DF_GREASE_QUIC_BIT`
+
 To initialize the settings structure to library defaults, use the following
 convenience function:
 
@@ -938,6 +946,11 @@ out of date.  Please check your :file:`lsquic.h` for actual values.*
 
     By default, do not use no-progress timeout on the client.
 
+.. macro:: LSQUIC_DF_GREASE_QUIC_BIT
+
+    By default, greasing the QUIC bit is enabled (if peer sent
+    the "grease_quic_bit" transport parameter).
+
 Receiving Packets
 -----------------
 

docs/conf.py

@@ -26,7 +26,7 @@
 # The short X.Y version
 version = u'2.18'
 # The full version, including alpha/beta/rc tags
-release = u'2.18.0'
+release = u'2.18.1'
 
 
 # -- General configuration ---------------------------------------------------

include/lsquic.h

@@ -25,7 +25,7 @@ extern "C" {
 
 #define LSQUIC_MAJOR_VERSION 2
 #define LSQUIC_MINOR_VERSION 18
-#define LSQUIC_PATCH_VERSION 0
+#define LSQUIC_PATCH_VERSION 1
 
 /**
  * Engine flags:
@@ -101,7 +101,7 @@ enum lsquic_version
 };
 
 /**
- * We currently support versions 43, 46, 50, Draft-27, and Draft-28.
+ * We currently support versions 43, 46, 50, Draft-27, Draft-28, and Draft-29.
  * @see lsquic_version
  */
 #define LSQUIC_SUPPORTED_VERSIONS ((1 << N_LSQVER) - 1)
@@ -344,6 +344,12 @@ typedef struct ssl_ctx_st * (*lsquic_lookup_cert_f)(
 /** By default, incoming packet size is not limited. */
 #define LSQUIC_DF_MAX_UDP_PAYLOAD_SIZE_RX 0
 
+/**
+ * By default, greasing the QUIC bit is enabled (if peer sent
+ * the "grease_quic_bit" transport parameter).
+ */
+#define LSQUIC_DF_GREASE_QUIC_BIT 1
+
 /** By default, drop no-progress connections after 60 seconds on the server */
 #define LSQUIC_DF_NOPROGRESS_TIMEOUT_SERVER 60
 
@@ -803,6 +809,15 @@ struct lsquic_engine_settings {
      * Default value is @ref LSQUIC_DF_MAX_UDP_PAYLOAD_SIZE_RX
      */
     unsigned short  es_max_udp_payload_size_rx;
+
+    /**
+     * Enable the "QUIC bit grease" extension.  When set to a true value,
+     * lsquic will grease the QUIC bit on the outgoing QUIC packets if
+     * the peer sent the "grease_quic_bit" transport parameter.
+     *
+     * Default value is @ref LSQUIC_DF_GREASE_QUIC_BIT
+     */
+    int             es_grease_quic_bit;
 };
 
 /* Initialize `settings' to default values */

src/liblsquic/lsquic_enc_sess_ietf.c

@@ -273,6 +273,7 @@ struct enc_sess_iquic
     struct lsquic_packet_out *
                          esi_hp_batch_packets[HP_BATCH_SIZE];
     unsigned char        esi_hp_batch_samples[HP_BATCH_SIZE][SAMPLE_SZ];
+    unsigned char        esi_grease;
 };
 
 
@@ -792,6 +793,7 @@ iquic_esfi_create_client (const char *hostname,
 
     enc_sess->esi_odcid = *dcid;
     enc_sess->esi_flags |= ESI_ODCID;
+    enc_sess->esi_grease = 0xFF;
 
     LSQ_DEBUGC("created client, DCID: %"CID_FMT, CID_BITS(dcid));
     {
@@ -878,6 +880,7 @@ iquic_esfi_create_server (struct lsquic_engine_public *enpub,
     enc_sess->esi_cryst_if = cryst_if;
     enc_sess->esi_enpub = enpub;
     enc_sess->esi_conn = lconn;
+    enc_sess->esi_grease = 0xFF;
 
     if (odcid)
     {
@@ -1259,6 +1262,8 @@ iquic_esfi_init_server (enc_session_t *enc_session_p)
         return -1;
     }
     maybe_setup_key_logging(enc_sess);
+    if (!enc_sess->esi_enpub->enp_lookup_cert && enc_sess->esi_keylog_handle)
+        SSL_CTX_set_keylog_callback(ssl_ctx, keylog_callback);
 
     transpa_len = gen_trans_params(enc_sess, u.trans_params,
                                                     sizeof(u.trans_params));
@@ -1711,6 +1716,17 @@ get_peer_transport_params (struct enc_sess_iquic *enc_sess)
     else
         LSQ_DEBUG("no QL bits");
 
+    if (trans_params->tp_set & (1 << TPI_GREASE_QUIC_BIT))
+    {
+        if (enc_sess->esi_enpub->enp_settings.es_grease_quic_bit)
+        {
+            LSQ_DEBUG("will grease the QUIC bit");
+            enc_sess->esi_grease = ~QUIC_BIT;
+        }
+        else
+            LSQ_DEBUG("greasing turned off: won't grease the QUIC bit");
+    }
+
     return 0;
 }
 
@@ -1980,6 +1996,7 @@ iquic_esf_encrypt_packet (enc_session_t *enc_session_p,
         goto err;
     if (enc_level == ENC_LEV_FORW)
         dst[0] |= enc_sess->esi_key_phase << 2;
+    dst[0] &= enc_sess->esi_grease | packet_out->po_path->np_dcid.idbuf[0];
 
     if (s_log_seal_and_open)
     {

src/liblsquic/lsquic_engine.c

@@ -356,6 +356,7 @@ lsquic_engine_init_settings (struct lsquic_engine_settings *settings,
     settings->es_spin            = LSQUIC_DF_SPIN;
     settings->es_delayed_acks    = LSQUIC_DF_DELAYED_ACKS;
     settings->es_timestamps      = LSQUIC_DF_TIMESTAMPS;
+    settings->es_grease_quic_bit = LSQUIC_DF_GREASE_QUIC_BIT;
 }
 
 

src/liblsquic/lsquic_full_conn_ietf.c

@@ -3825,6 +3825,9 @@ generate_connection_close_packet (struct ietf_full_conn *conn)
     struct lsquic_packet_out *packet_out;
     int sz;
 
+    /* FIXME Select PNS based on handshake status (possible on the client): if
+     * appropriate keys are not available, encryption will fail.
+     */
     packet_out = lsquic_send_ctl_new_packet_out(&conn->ifc_send_ctl, 0, PNS_APP,
                                                                 CUR_NPATH(conn));
     if (!packet_out)
@@ -6610,7 +6613,8 @@ ietf_full_conn_ci_packet_not_sent (struct lsquic_conn *lconn,
                                    struct lsquic_packet_out *packet_out)
 {
 #ifndef NDEBUG
-    assert(packet_out->po_lflags & POL_HEADER_PROT);
+    if (packet_out->po_flags & PO_ENCRYPTED)
+        assert(packet_out->po_lflags & POL_HEADER_PROT);
 #endif
     struct ietf_full_conn *conn = (struct ietf_full_conn *) lconn;
     lsquic_send_ctl_delayed_one(&conn->ifc_send_ctl, packet_out);
@@ -6625,7 +6629,8 @@ pre_hsk_packet_sent_or_delayed (struct ietf_full_conn *conn,
                                const struct lsquic_packet_out *packet_out)
 {
 #ifndef NDEBUG
-    assert(packet_out->po_lflags & POL_HEADER_PROT);
+    if (packet_out->po_flags & PO_ENCRYPTED)
+        assert(packet_out->po_lflags & POL_HEADER_PROT);
 #endif
     /* Once IFC_IGNORE_INIT is set, the pre-hsk wrapper is removed: */
     assert(!(conn->ifc_flags & IFC_IGNORE_INIT));
@@ -7192,7 +7197,7 @@ ietf_full_conn_ci_get_log_cid (const struct lsquic_conn *lconn)
         else
             return CN_SCID(lconn);
     }
-    if (CUR_DCID(conn)->len)
+    if (CN_SCID(lconn)->len)
         return CN_SCID(lconn);
     else
         return CUR_DCID(conn);

src/liblsquic/lsquic_packet_ietf.h

@@ -28,4 +28,6 @@
  */
 #define IQUIC_MAX_OUT_PACKET_SZ ((1u << 14) - 1)
 
+#define QUIC_BIT 0x40
+
 #endif

src/liblsquic/lsquic_parse_ietf_v1.c

@@ -264,7 +264,7 @@ gen_short_pkt_header (const struct lsquic_conn *lconn,
     if (need > bufsz)
         return -1;
 
-    buf[0] = 0x40
+    buf[0] = QUIC_BIT
            | (lsquic_packet_out_spin_bit(packet_out) << 5)
            | (lsquic_packet_out_square_bit(packet_out) << 4)
            | (lsquic_packet_out_loss_bit(packet_out) << 3)
@@ -2007,7 +2007,7 @@ lsquic_ietf_v1_gen_ver_nego_pkt (unsigned char *buf, size_t bufsz,
     if (need > bufsz)
         return -1;
 
-    *buf++ = 0x80 | 0x40 | rand;
+    *buf++ = 0x80 | QUIC_BIT | rand;
     memset(buf, 0, 4);
     buf += 4;
 

src/liblsquic/lsquic_stream.c

@@ -3869,15 +3869,7 @@ stream_uh_in_gquic (struct lsquic_stream *stream,
         LSQ_DEBUG("received uncompressed headers");
         stream->stream_flags |= STREAM_HAVE_UH;
         if (uh->uh_flags & UH_FIN)
-        {
-            /* IETF QUIC only sets UH_FIN for a pushed stream on the server to
-             * mark request as done:
-             */
-            if (stream->sm_bflags & SMBF_IETF)
-                assert((stream->sm_bflags & SMBF_SERVER)
-                                            && lsquic_stream_is_pushed(stream));
             stream->stream_flags |= STREAM_FIN_RECVD|STREAM_HEAD_IN_FIN;
-        }
         stream->uh = uh;
         if (uh->uh_oth_stream_id == 0)
         {

src/liblsquic/lsquic_trans_params.c

@@ -58,6 +58,7 @@ tpi_val_2_enum (uint64_t tpi_val)
     case 0xC37:     return TPI_QUANTUM_READINESS;
 #endif
     case 0x1057:    return TPI_LOSS_BITS;
+    case 0x2AB2:    return TPI_GREASE_QUIC_BIT;
     case 0xDE1A:    return TPI_MIN_ACK_DELAY;
     case 0x7157:    return TPI_TIMESTAMPS;
     default:        return INT_MAX;
@@ -90,6 +91,7 @@ static const unsigned enum_2_tpi_val[LAST_TPI + 1] =
     [TPI_LOSS_BITS]                         =  0x1057,
     [TPI_MIN_ACK_DELAY]                     =  0xDE1A,
     [TPI_TIMESTAMPS]                        =  0x7157,
+    [TPI_GREASE_QUIC_BIT]                   =  0x2AB2,
 };
 
 
@@ -118,6 +120,7 @@ const char * const lsquic_tpi2str[LAST_TPI + 1] =
     [TPI_LOSS_BITS]                         =  "loss_bits",
     [TPI_MIN_ACK_DELAY]                     =  "min_ack_delay",
     [TPI_TIMESTAMPS]                        =  "timestamps",
+    [TPI_GREASE_QUIC_BIT]                   =  "grease_quic_bit",
 };
 #define tpi2str lsquic_tpi2str
 
@@ -410,6 +413,7 @@ lsquic_tp_encode (const struct transport_params *params, int is_server,
                 break;
             case TPI_DISABLE_ACTIVE_MIGRATION:
             case TPI_TIMESTAMPS:
+            case TPI_GREASE_QUIC_BIT:
                 *p++ = 0;
                 break;
 #if LSQUIC_TEST_QUANTUM_READINESS
@@ -533,6 +537,7 @@ lsquic_tp_decode (const unsigned char *const buf, size_t bufsz,
             break;
         case TPI_DISABLE_ACTIVE_MIGRATION:
         case TPI_TIMESTAMPS:
+        case TPI_GREASE_QUIC_BIT:
             EXPECT_LEN(0);
             break;
         case TPI_STATELESS_RESET_TOKEN:
@@ -919,6 +924,7 @@ lsquic_tp_encode_27 (const struct transport_params *params, int is_server,
                 break;
             case TPI_DISABLE_ACTIVE_MIGRATION:
             case TPI_TIMESTAMPS:
+            case TPI_GREASE_QUIC_BIT:
                 *p++ = 0;
                 break;
 #if LSQUIC_TEST_QUANTUM_READINESS

src/liblsquic/lsquic_trans_params.h

@@ -39,6 +39,7 @@ enum transport_param_id
      * Empty transport parameters:
      */
     TPI_TIMESTAMPS,
+    TPI_GREASE_QUIC_BIT,
     TPI_DISABLE_ACTIVE_MIGRATION,           MAX_EMPTY_TPI = TPI_DISABLE_ACTIVE_MIGRATION,
 
     /*