Release 2.4.2

- [BUGFIX] H3 framing: fix zero-byte write when space is available
- [BUGFIX] Don't send STREAM frame when incoming unidirectgional stream
  is closed
- [BUGFIX] Cancel all pending writes by stream reset by a GOAWAY
- [BUGFIX] Fix use-after-free in IETF full conn
- [OPTIMIZATION] Wait for session tickets for two seconds and then drop
  SSL object and crypto streams.

CHANGELOG

@@ -1,3 +1,13 @@
+2019-09-23
+    - 2.4.2
+    - [BUGFIX] H3 framing: fix zero-byte write when space is available
+    - [BUGFIX] Don't send STREAM frame when incoming unidirectgional stream
+      is closed
+    - [BUGFIX] Cancel all pending writes by stream reset by a GOAWAY
+    - [BUGFIX] Fix use-after-free in IETF full conn
+    - [OPTIMIZATION] Wait for session tickets for two seconds and then drop
+      SSL object and crypto streams.
+
 2019-09-18
     - 2.4.0
     - [FEATURE] QUIC and HTTP/3 Internet Draft 23 support

include/lsquic.h

@@ -25,7 +25,7 @@ extern "C" {
 
 #define LSQUIC_MAJOR_VERSION 2
 #define LSQUIC_MINOR_VERSION 4
-#define LSQUIC_PATCH_VERSION 0
+#define LSQUIC_PATCH_VERSION 2
 
 /**
  * Engine flags:

src/liblsquic/lsquic_alarmset.c

@@ -47,6 +47,7 @@ static const char *const lsquic_alid2str[] =
     [AL_CID_THROT]  =  "CID_THROT",
     [AL_PATH_CHAL_0] = "PATH_CHAL_0",
     [AL_PATH_CHAL_1] = "PATH_CHAL_1",
+    [AL_SESS_TICKET] = "SESS_TICKET",
 };
 
 

src/liblsquic/lsquic_alarmset.h

@@ -35,6 +35,7 @@ enum alarm_id {
     AL_PATH_CHAL,
     AL_PATH_CHAL_0 = AL_PATH_CHAL,
     AL_PATH_CHAL_1,
+    AL_SESS_TICKET,
     MAX_LSQUIC_ALARMS
 };
 
@@ -54,6 +55,7 @@ enum alarm_id_bit {
     ALBIT_PATH_CHAL = 1 << AL_PATH_CHAL,
     ALBIT_PATH_CHAL_0 = 1 << AL_PATH_CHAL_0,
     ALBIT_PATH_CHAL_1 = 1 << AL_PATH_CHAL_1,
+    ALBIT_SESS_TICKET = 1 << AL_SESS_TICKET,
 };
 
 

src/liblsquic/lsquic_conn.h

@@ -240,6 +240,10 @@ struct conn_iface
 
     const lsquic_cid_t *
     (*ci_get_log_cid) (const struct lsquic_conn *);
+
+    /* Optional method.  Only used by the IETF client code. */
+    void
+    (*ci_drop_crypto_streams) (struct lsquic_conn *);
 };
 
 #define LSCONN_CCE_BITS 3

src/liblsquic/lsquic_enc_sess.h

@@ -2,6 +2,7 @@
 #ifndef LSQUIC_ENC_SESS_H
 #define LSQUIC_ENC_SESS_H 1
 
+struct lsquic_alarmset;
 struct lsquic_engine_public;
 struct lsquic_packet_out;
 struct lsquic_packet_in;
@@ -262,7 +263,8 @@ struct enc_session_funcs_iquic
                            struct lsquic_conn *, const struct lsquic_cid *,
                            const struct ver_neg *, void *(crypto_streams)[4],
                            const struct crypto_stream_if *,
-                           const unsigned char *, size_t);
+                           const unsigned char *, size_t,
+                           struct lsquic_alarmset *);
 
     void
     (*esfi_destroy) (enc_session_t *);

src/liblsquic/lsquic_enc_sess_ietf.c

@@ -44,6 +44,7 @@
 #include "lsquic_frab_list.h"
 #include "lsquic_tokgen.h"
 #include "lsquic_ietf.h"
+#include "lsquic_alarmset.h"
 
 #if __GNUC__
 #   define UNLIKELY(cond) __builtin_expect(cond, 0)
@@ -106,6 +107,10 @@ iquic_esf_get_server_cert_chain (enc_session_t *);
 static void
 maybe_drop_SSL (struct enc_sess_iquic *);
 
+static void
+no_sess_ticket (enum alarm_id alarm_id, void *ctx,
+                                  lsquic_time_t expiry, lsquic_time_t now);
+
 
 typedef void (*gen_hp_mask_f)(struct enc_sess_iquic *,
     const struct header_prot *, unsigned cliser,
@@ -236,6 +241,7 @@ struct enc_sess_iquic
         ESI_ALPN_CHECKED = 1 << 8,
         ESI_CACHED_INFO  = 1 << 9,
         ESI_1RTT_ACKED   = 1 << 10,
+        ESI_WANT_TICKET  = 1 << 11,
     }                    esi_flags;
     enum evp_aead_direction_t
                          esi_dir[2];        /* client, server */
@@ -264,6 +270,8 @@ struct enc_sess_iquic
     struct frab_list     esi_frals[N_ENC_LEVS];
     struct transport_params
                          esi_peer_tp;
+    struct lsquic_alarmset
+                        *esi_alset;
 };
 
 
@@ -651,7 +659,8 @@ iquic_esfi_create_client (const char *hostname,
             struct lsquic_engine_public *enpub, struct lsquic_conn *lconn,
             const lsquic_cid_t *dcid, const struct ver_neg *ver_neg,
             void *crypto_streams[4], const struct crypto_stream_if *cryst_if,
-            const unsigned char *zero_rtt, size_t zero_rtt_sz)
+            const unsigned char *zero_rtt, size_t zero_rtt_sz,
+            struct lsquic_alarmset *alset)
 {
     struct enc_sess_iquic *enc_sess;
 
@@ -720,6 +729,12 @@ iquic_esfi_create_client (const char *hostname,
         enc_sess->esi_zero_rtt_sz = 0;
     }
 
+    if (enc_sess->esi_enpub->enp_stream_if->on_zero_rtt_info)
+        enc_sess->esi_flags |= ESI_WANT_TICKET;
+    enc_sess->esi_alset = alset;
+    lsquic_alarmset_init_alarm(enc_sess->esi_alset, AL_SESS_TICKET,
+                                            no_sess_ticket, enc_sess);
+
     return enc_sess;
 }
 
@@ -1192,6 +1207,8 @@ iquic_new_session_cb (SSL *ssl, SSL_SESSION *session)
     enc_sess->esi_enpub->enp_stream_if->on_zero_rtt_info(enc_sess->esi_conn,
                                                                 buf, buf_sz);
     free(buf);
+    enc_sess->esi_flags &= ~ESI_WANT_TICKET;
+    lsquic_alarmset_unset(enc_sess->esi_alset, AL_SESS_TICKET);
     return 0;
 }
 
@@ -2202,6 +2219,20 @@ cache_info (struct enc_sess_iquic *enc_sess)
 }
 
 
+static void
+drop_SSL (struct enc_sess_iquic *enc_sess)
+{
+    LSQ_DEBUG("drop SSL object");
+    if (enc_sess->esi_conn->cn_if->ci_drop_crypto_streams)
+        enc_sess->esi_conn->cn_if->ci_drop_crypto_streams(
+                                                    enc_sess->esi_conn);
+    cache_info(enc_sess);
+    SSL_free(enc_sess->esi_ssl);
+    enc_sess->esi_ssl = NULL;
+    free_handshake_keys(enc_sess);
+}
+
+
 static void
 maybe_drop_SSL (struct enc_sess_iquic *enc_sess)
 {
@@ -2216,15 +2247,32 @@ maybe_drop_SSL (struct enc_sess_iquic *enc_sess)
         && enc_sess->esi_ssl
         && lsquic_frab_list_empty(&enc_sess->esi_frals[ENC_LEV_FORW]))
     {
-        LSQ_DEBUG("drop SSL object");
-        cache_info(enc_sess);
-        SSL_free(enc_sess->esi_ssl);
-        enc_sess->esi_ssl = NULL;
-        free_handshake_keys(enc_sess);
+        if ((enc_sess->esi_flags & (ESI_SERVER|ESI_WANT_TICKET))
+                                                            != ESI_WANT_TICKET)
+            drop_SSL(enc_sess);
+        else if (enc_sess->esi_alset
+                && !lsquic_alarmset_is_set(enc_sess->esi_alset, AL_SESS_TICKET))
+        {
+            LSQ_DEBUG("no session ticket: delay dropping SSL object");
+            lsquic_alarmset_set(enc_sess->esi_alset, AL_SESS_TICKET,
+                /* Wait up to two seconds for session tickets */
+                                                lsquic_time_now() + 2000000);
+        }
     }
 }
 
 
+static void
+no_sess_ticket (enum alarm_id alarm_id, void *ctx,
+                                  lsquic_time_t expiry, lsquic_time_t now)
+{
+    struct enc_sess_iquic *enc_sess = ctx;
+
+    LSQ_DEBUG("no session tickets forthcoming -- drop SSL");
+    drop_SSL(enc_sess);
+}
+
+
 typedef char enums_have_the_same_value[
     (int) ssl_encryption_initial     == (int) ENC_LEV_CLEAR &&
     (int) ssl_encryption_early_data  == (int) ENC_LEV_EARLY &&
@@ -2583,23 +2631,43 @@ readf_cb (void *ctx, const unsigned char *buf, size_t len, int fin)
 }
 
 
+static size_t
+discard_cb (void *ctx, const unsigned char *buf, size_t len, int fin)
+{
+    return len;
+}
+
+
 static void
 chsk_ietf_on_read (struct lsquic_stream *stream, lsquic_stream_ctx_t *ctx)
 {
     struct enc_sess_iquic *const enc_sess = (void *) ctx;
     enum enc_level enc_level = enc_sess->esi_cryst_if->csi_enc_level(stream);
     struct readf_ctx readf_ctx = { enc_sess, enc_level, 0, };
+    ssize_t nread;
 
 
-    ssize_t nread = enc_sess->esi_cryst_if->csi_readf(stream,
-                                                    readf_cb, &readf_ctx);
-
-    if (!(nread < 0 || readf_ctx.err))
-        iquic_esfi_shake_stream((enc_session_t *)enc_sess, stream, "on_read");
+    if (enc_sess->esi_ssl)
+    {
+        nread = enc_sess->esi_cryst_if->csi_readf(stream, readf_cb, &readf_ctx);
+        if (!(nread < 0 || readf_ctx.err))
+            iquic_esfi_shake_stream((enc_session_t *)enc_sess, stream,
+                                                                    "on_read");
+        else
+            enc_sess->esi_conn->cn_if->ci_internal_error(enc_sess->esi_conn,
+                "shaking stream failed: nread: %zd, err: %d, SSL err: %"PRIu32,
+                nread, readf_ctx.err, ERR_get_error());
+    }
     else
-        enc_sess->esi_conn->cn_if->ci_internal_error(enc_sess->esi_conn,
-            "shaking stream failed: nread: %zd, err: %d, SSL err: %"PRIu32,
-            nread, readf_ctx.err, ERR_get_error());
+    {
+        /* This branch is reached when we don't want TLS ticket and drop
+         * the SSL object before we process TLS tickets that have been
+         * already received and waiting in the incoming stream buffer.
+         */
+        nread = enc_sess->esi_cryst_if->csi_readf(stream, discard_cb, NULL);
+        lsquic_stream_wantread(stream, 0);
+        LSQ_DEBUG("no SSL object: discard %zd bytes of SSL data", nread);
+    }
 }