From: Hugo Landau <hlandau@openssl.org>
Date: Tue, 6 Jun 2023 15:25:10 +0000 (+0100)
Subject: QUIC QSM: Free unneeded stream buffers, calculate RESET_STREAM final size correctly
X-Git-Tag: openssl-3.2.0-alpha1~457
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=28d0e35cd675c67355d91caf65aa180df49f9db4;p=thirdparty%2Fopenssl.git

QUIC QSM: Free unneeded stream buffers, calculate RESET_STREAM final size correctly

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/21135)
---

diff --git a/ssl/quic/quic_stream_map.c b/ssl/quic/quic_stream_map.c
index a6fe8ab9bdc..007bef521c7 100644
--- a/ssl/quic/quic_stream_map.c
+++ b/ssl/quic/quic_stream_map.c
@@ -406,8 +406,8 @@ int ossl_quic_stream_map_notify_totally_acked(QUIC_STREAM_MAP *qsm,
     case QUIC_SSTREAM_STATE_DATA_SENT:
         qs->send_state = QUIC_SSTREAM_STATE_DATA_RECVD;
         /* We no longer need a QUIC_SSTREAM in this state. */
-        //ossl_quic_sstream_free(qs->sstream);
-        //qs->sstream = NULL;
+        ossl_quic_sstream_free(qs->sstream);
+        qs->sstream = NULL;
         return 1;
     }
 }
@@ -416,6 +416,8 @@ int ossl_quic_stream_map_reset_stream_send_part(QUIC_STREAM_MAP *qsm,
                                                 QUIC_STREAM *qs,
                                                 uint64_t aec)
 {
+    uint64_t final_size;
+
     switch (qs->send_state) {
     default:
     case QUIC_SSTREAM_STATE_NONE:
@@ -434,11 +436,27 @@ int ossl_quic_stream_map_reset_stream_send_part(QUIC_STREAM_MAP *qsm,
     case QUIC_SSTREAM_STATE_READY:
     case QUIC_SSTREAM_STATE_SEND:
     case QUIC_SSTREAM_STATE_DATA_SENT:
+        /*
+         * If we already have a final size (e.g. because we are coming from
+         * DATA_SENT), we have to be consistent with that, so don't change it.
+         * If we don't already have a final size, determine a final size value.
+         * This is the value which we will end up using for a RESET_STREAM frame
+         * for flow control purposes. We could send the stream size (total
+         * number of bytes appended to QUIC_SSTREAM by the application), but it
+         * is in our interest to exclude any bytes we have not actually
+         * transmitted yet, to avoid unnecessarily consuming flow control
+         * credit. We can get this from the TXFC.
+         */
+        if (!ossl_quic_stream_send_get_final_size(qs, &final_size))
+            qs->send_final_size = ossl_quic_txfc_get_swm(&qs->txfc);
+
         qs->reset_stream_aec    = aec;
-        qs->send_state          = QUIC_SSTREAM_STATE_RESET_SENT;
         qs->want_reset_stream   = 1;
+        qs->send_state          = QUIC_SSTREAM_STATE_RESET_SENT;
+
+        ossl_quic_sstream_free(qs->sstream);
+        qs->sstream = NULL;
 
-        /* TODO free */
         ossl_quic_stream_map_update_state(qsm, qs);
         return 1;
 
@@ -536,8 +554,8 @@ int ossl_quic_stream_map_notify_totally_read(QUIC_STREAM_MAP *qsm,
         qs->recv_state = QUIC_RSTREAM_STATE_DATA_READ;
 
         /* QUIC_RSTREAM is no longer needed */
-        //ossl_quic_rstream_free(qs->rstream);
-        //qs->rstream = NULL;
+        ossl_quic_rstream_free(qs->rstream);
+        qs->rstream = NULL;
         return 1;
     }
 }
@@ -562,8 +580,8 @@ int ossl_quic_stream_map_notify_reset_recv_part(QUIC_STREAM_MAP *qsm,
         qs->want_stop_sending       = 0;
 
         /* QUIC_RSTREAM is no longer needed */
-        //ossl_quic_rstream_free(qs->rstream);
-        //qs->rstream = NULL;
+        ossl_quic_rstream_free(qs->rstream);
+        qs->rstream = NULL;
 
         ossl_quic_stream_map_update_state(qsm, qs);
         return 1;
diff --git a/ssl/quic/quic_txp.c b/ssl/quic/quic_txp.c
index 6c11d4bed3f..cb44b0aa693 100644
--- a/ssl/quic/quic_txp.c
+++ b/ssl/quic/quic_txp.c
@@ -1839,8 +1839,9 @@ static int txp_generate_stream_related(OSSL_QUIC_TX_PACKETISER *txp,
 
             f.stream_id         = stream->id;
             f.app_error_code    = stream->reset_stream_aec;
-            /* XXX fix this - use how much we've actually sent */
-            f.final_size        = ossl_quic_sstream_get_cur_size(stream->sstream);
+            if (!ossl_quic_stream_send_get_final_size(stream, &f.final_size))
+                return 0; /* should not be possible */
+
             if (!ossl_quic_wire_encode_frame_reset_stream(wpkt, &f)) {
                 tx_helper_rollback(h); /* can't fit */
                 txp_enlink_tmp(tmp_head, stream);
diff --git a/test/quic_txp_test.c b/test/quic_txp_test.c
index 013f542170c..b733dcaf1c5 100644
--- a/test/quic_txp_test.c
+++ b/test/quic_txp_test.c
@@ -1033,7 +1033,7 @@ static ossl_unused int check_stream_13(struct helper *h)
 {
     if (!TEST_uint64_t_eq(h->frame.reset_stream.stream_id, 42)
         || !TEST_uint64_t_eq(h->frame.reset_stream.app_error_code, 4568)
-        || !TEST_uint64_t_eq(h->frame.reset_stream.final_size, 8))
+        || !TEST_uint64_t_eq(h->frame.reset_stream.final_size, 0))
         return 0;
 
     return 1;