QUIC: updated specification references.

This includes updating citations and further clarification.

11 files changed, 128 insertions, 70 deletions

diff --git a/src/event/quic/ngx_event_quic.c b/src/event/quic/ngx_event_quic.c
index c89a99223..f0dd943a6 100644
--- a/src/event/quic/ngx_event_quic.c
+++ b/src/event/quic/ngx_event_quic.c
@@ -506,10 +506,11 @@ ngx_quic_close_quic(ngx_connection_t *c, ngx_int_t rc)
         if (rc == NGX_DONE) {
 
             /*
-             *  10.2.  Idle Timeout
+             * RFC 9000, 10.1.  Idle Timeout
              *
-             *  If the idle timeout is enabled by either peer, a connection is
-             *  silently closed and its state is discarded when it remains idle
+             *  If a max_idle_timeout is specified by either endpoint in its
+             *  transport parameters (Section 18.2), the connection is silently
+             *  closed and its state is discarded when it remains idle
              */
 
             ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
@@ -519,7 +520,7 @@ ngx_quic_close_quic(ngx_connection_t *c, ngx_int_t rc)
         } else {
 
             /*
-             * 10.3.  Immediate Close
+             * RFC 9000, 10.2.  Immediate Close
              *
              *  An endpoint sends a CONNECTION_CLOSE frame (Section 19.19)
              *  to terminate the connection immediately.
@@ -708,10 +709,10 @@ ngx_quic_input(ngx_connection_t *c, ngx_buf_t *b, ngx_quic_conf_t *conf)
          * Instead of queueing it, we ignore it and rely on the sender's
          * retransmission:
          *
-         * 12.2.  Coalescing Packets:
+         * RFC 9000, 12.2.  Coalescing Packets
          *
          * For example, if decryption fails (because the keys are
-         * not available or any other reason), the receiver MAY either
+         * not available or for any other reason), the receiver MAY either
          * discard or buffer the packet for later processing and MUST
          * attempt to process the remaining packets.
          *
@@ -831,7 +832,7 @@ ngx_quic_process_packet(ngx_connection_t *c, ngx_quic_conf_t *conf,
     c->log->action = "processing initial packet";
 
     if (pkt->dcid.len < NGX_QUIC_CID_LEN_MIN) {
-        /* 7.2.  Negotiating Connection IDs */
+        /* RFC 9000, 7.2.  Negotiating Connection IDs */
         ngx_log_error(NGX_LOG_INFO, c->log, 0,
                       "quic too short dcid in initial"
                       " packet: len:%i", pkt->dcid.len);
@@ -944,7 +945,9 @@ ngx_quic_process_payload(ngx_connection_t *c, ngx_quic_header_t *pkt)
 
     if (pkt->level == ssl_encryption_handshake) {
         /*
-         * 4.10.1. The successful use of Handshake packets indicates
+         * RFC 9001, 4.9.1.  Discarding Initial Keys
+         *
+         * The successful use of Handshake packets indicates
          * that no more Initial packets need to be exchanged
          */
         ngx_quic_discard_ctx(c, ssl_encryption_initial);
@@ -957,12 +960,13 @@ ngx_quic_process_payload(ngx_connection_t *c, ngx_quic_header_t *pkt)
 
     if (qc->closing) {
         /*
-         * 10.1  Closing and Draining Connection States
+         * RFC 9000, 10.2.  Immediate Close
+         *
          * ... delayed or reordered packets are properly discarded.
          *
-         *  An endpoint retains only enough information to generate
-         *  a packet containing a CONNECTION_CLOSE frame and to identify
-         *  packets as belonging to the connection.
+         *  In the closing state, an endpoint retains only enough information
+         *  to generate a packet containing a CONNECTION_CLOSE frame and to
+         *  identify packets as belonging to the connection.
          */
 
         qc->error_level = pkt->level;
@@ -1331,6 +1335,8 @@ ngx_quic_handle_frames(ngx_connection_t *c, ngx_quic_header_t *pkt)
 
         if (qsock->path != qc->socket->path && nonprobing) {
             /*
+             * RFC 9000, 9.2.  Initiating Connection Migration
+             *
              * An endpoint can migrate a connection to a new local
              * address by sending packets containing non-probing frames
              * from that address.
diff --git a/src/event/quic/ngx_event_quic_ack.c b/src/event/quic/ngx_event_quic_ack.c
index 368e868d8..c4e924c8e 100644
--- a/src/event/quic/ngx_event_quic_ack.c
+++ b/src/event/quic/ngx_event_quic_ack.c
@@ -12,13 +12,13 @@
 
 #define NGX_QUIC_MAX_ACK_GAP                 2
 
-/* quic-recovery, section 6.1.1, Packet Threshold */
+/* RFC 9002, 6.1.1. Packet Threshold: kPacketThreshold */
 #define NGX_QUIC_PKT_THR                     3 /* packets */
-/* quic-recovery, section 6.1.2, Time Threshold */
+/* RFC 9002, 6.1.2. Time Threshold: kTimeThreshold, kGranularity */
 #define NGX_QUIC_TIME_THR                    1.125
 #define NGX_QUIC_TIME_GRANULARITY            1 /* ms */
 
-/* quic-recovery, section 7.6.1 Persistent congestion duration */
+/* RFC 9002, 7.6.1. Duration: kPersistentCongestionThreshold */
 #define NGX_QUIC_PERSISTENT_CONGESTION_THR   3
 
 #define ngx_quic_lost_threshold(qc)                                           \
@@ -73,9 +73,10 @@ ngx_quic_handle_ack_frame(ngx_connection_t *c, ngx_quic_header_t *pkt,
     ack = &f->u.ack;
 
     /*
+     * RFC 9000, 19.3.1.  ACK Ranges
+     *
      *  If any computed packet number is negative, an endpoint MUST
      *  generate a connection error of type FRAME_ENCODING_ERROR.
-     *  (19.3.1)
      */
 
     if (ack->first_range > ack->largest) {
@@ -97,13 +98,15 @@ ngx_quic_handle_ack_frame(ngx_connection_t *c, ngx_quic_header_t *pkt,
         return NGX_ERROR;
     }
 
-    /* 13.2.3.  Receiver Tracking of ACK Frames */
+    /* RFC 9000, 13.2.4.  Limiting Ranges by Tracking ACK Frames */
     if (ctx->largest_ack < max || ctx->largest_ack == NGX_QUIC_UNSET_PN) {
         ctx->largest_ack = max;
         ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
                        "quic updated largest received ack:%uL", max);
 
         /*
+         * RFC 9002, 5.1.  Generating RTT Samples
+         *
          *  An endpoint generates an RTT sample on receiving an
          *  ACK frame that meets the following two conditions:
          *
@@ -470,7 +473,7 @@ ngx_quic_detect_lost(ngx_connection_t *c, ngx_quic_ack_stat_t *st)
     }
 
 
-    /* Establishing Persistent Congestion (7.6.2) */
+    /* RFC 9002, 7.6.2.  Establishing Persistent Congestion */
 
     /*
      * Once acknowledged, packets are no longer tracked. Thus no send time
@@ -757,7 +760,7 @@ ngx_quic_pto(ngx_connection_t *c, ngx_quic_send_ctx_t *ctx)
 
     qc = ngx_quic_get_connection(c);
 
-    /* PTO calculation: quic-recovery, Appendix 8 */
+    /* RFC 9002, Appendix A.8.  Setting the Loss Detection Timer */
     duration = qc->avg_rtt;
 
     duration += ngx_max(4 * qc->rttvar, NGX_QUIC_TIME_GRANULARITY);
diff --git a/src/event/quic/ngx_event_quic_connection.h b/src/event/quic/ngx_event_quic_connection.h
index e6ef438e4..79c95a13e 100644
--- a/src/event/quic/ngx_event_quic_connection.h
+++ b/src/event/quic/ngx_event_quic_connection.h
@@ -38,7 +38,7 @@ typedef struct ngx_quic_keys_s        ngx_quic_keys_t;
 #include <ngx_event_quic_socket.h>
 
 
-/* quic-recovery, section 6.2.2, kInitialRtt */
+/* RFC 9002, 6.2.2.  Handshakes and New Paths: kInitialRtt */
 #define NGX_QUIC_INITIAL_RTT                 333 /* ms */
 
 #define NGX_QUIC_UNSET_PN                    (uint64_t) -1
@@ -143,13 +143,13 @@ typedef struct {
 
 
 /*
- * 12.3.  Packet Numbers
+ * RFC 9000, 12.3.  Packet Numbers
  *
  *  Conceptually, a packet number space is the context in which a packet
  *  can be processed and acknowledged.  Initial packets can only be sent
- *  with Initial packet protection keys and acknowledged in packets which
+ *  with Initial packet protection keys and acknowledged in packets that
  *  are also Initial packets.
-*/
+ */
 struct ngx_quic_send_ctx_s {
     enum ssl_encryption_level_t       level;
 
diff --git a/src/event/quic/ngx_event_quic_connid.c b/src/event/quic/ngx_event_quic_connid.c
index ca9218fcb..273b58c65 100644
--- a/src/event/quic/ngx_event_quic_connid.c
+++ b/src/event/quic/ngx_event_quic_connid.c
@@ -86,11 +86,13 @@ ngx_quic_handle_new_connection_id_frame(ngx_connection_t *c,
 
     if (f->seqnum < qc->max_retired_seqnum) {
         /*
+         * RFC 9000, 19.15.  NEW_CONNECTION_ID Frame
+         *
          *  An endpoint that receives a NEW_CONNECTION_ID frame with
          *  a sequence number smaller than the Retire Prior To field
          *  of a previously received NEW_CONNECTION_ID frame MUST send
          *  a corresponding RETIRE_CONNECTION_ID frame that retires
-         *  the newly received connection  ID, unless it has already
+         *  the newly received connection ID, unless it has already
          *  done so for that sequence number.
          */
 
@@ -117,8 +119,8 @@ ngx_quic_handle_new_connection_id_frame(ngx_connection_t *c,
 
     if (cid) {
         /*
-         * Transmission errors, timeouts and retransmissions might cause the
-         * same NEW_CONNECTION_ID frame to be received multiple times
+         * Transmission errors, timeouts, and retransmissions might cause the
+         * same NEW_CONNECTION_ID frame to be received multiple times.
          */
 
         if (cid->len != f->len
@@ -126,7 +128,7 @@ ngx_quic_handle_new_connection_id_frame(ngx_connection_t *c,
             || ngx_strncmp(cid->sr_token, f->srt, NGX_QUIC_SR_TOKEN_LEN) != 0)
         {
             /*
-             * ..a sequence number is used for different connection IDs,
+             * ..if a sequence number is used for different connection IDs,
              * the endpoint MAY treat that receipt as a connection error
              * of type PROTOCOL_VIOLATION.
              */
@@ -190,6 +192,8 @@ done:
 
     if (qc->nclient_ids > qc->tp.active_connection_id_limit) {
         /*
+         * RFC 9000, 5.1.1.  Issuing Connection IDs
+         *
          * After processing a NEW_CONNECTION_ID frame and
          * adding and retiring active connection IDs, if the number of active
          * connection IDs exceeds the value advertised in its
diff --git a/src/event/quic/ngx_event_quic_migration.c b/src/event/quic/ngx_event_quic_migration.c
index d6300012d..53e11d9c6 100644
--- a/src/event/quic/ngx_event_quic_migration.c
+++ b/src/event/quic/ngx_event_quic_migration.c
@@ -38,15 +38,17 @@ ngx_quic_handle_path_challenge_frame(ngx_connection_t *c,
     frame.u.path_response = *f;
 
     /*
+     * RFC 9000, 8.2.2.  Path Validation Responses
+     *
      * A PATH_RESPONSE frame MUST be sent on the network path where the
-     * PATH_CHALLENGE was received.
+     * PATH_CHALLENGE frame was received.
      */
     qsock = ngx_quic_get_socket(c);
     path = qsock->path;
 
     /*
-     *  An endpoint MUST NOT expand the datagram containing the PATH_RESPONSE
-     *  if the resulting data exceeds the anti-amplification limit.
+     * An endpoint MUST NOT expand the datagram containing the PATH_RESPONSE
+     * if the resulting data exceeds the anti-amplification limit.
      */
     max = path->received * 3;
     max = (path->sent >= max) ? 0 : max - path->sent;
@@ -61,6 +63,8 @@ ngx_quic_handle_path_challenge_frame(ngx_connection_t *c,
 
     if (qsock == qc->socket) {
         /*
+         * RFC 9000, 9.3.3.  Off-Path Packet Forwarding
+         *
          * An endpoint that receives a PATH_CHALLENGE on an active path SHOULD
          * send a non-probing packet in response.
          */
@@ -91,6 +95,8 @@ ngx_quic_handle_path_response_frame(ngx_connection_t *c,
     qc = ngx_quic_get_connection(c);
 
     /*
+     * RFC 9000, 8.2.3.  Successful Path Validation
+     *
      * A PATH_RESPONSE frame received on any network path validates the path
      * on which the PATH_CHALLENGE was sent.
      */
@@ -120,11 +126,12 @@ ngx_quic_handle_path_response_frame(ngx_connection_t *c,
 valid:
 
     /*
+     * RFC 9000, 9.4.  Loss Detection and Congestion Control
+     *
      * On confirming a peer's ownership of its new address,
      * an endpoint MUST immediately reset the congestion controller
-     * and round-trip time estimator for the new path
-     * to initial values
-     * ...unless the only change in the peer's address is its port number.
+     * and round-trip time estimator for the new path to initial values
+     * unless the only change in the peer's address is its port number.
      */
 
     prev = qc->backup->path;
@@ -144,6 +151,8 @@ valid:
     }
 
     /*
+     * RFC 9000, 9.3.  Responding to Connection Migration
+     *
      *  After verifying a new client address, the server SHOULD
      *  send new address validation tokens (Section 8) to the client.
      */
@@ -474,6 +483,8 @@ ngx_quic_handle_migration(ngx_connection_t *c, ngx_quic_header_t *pkt)
     ctx = ngx_quic_get_send_ctx(qc, pkt->level);
 
     /*
+     * RFC 9000, 9.3.  Responding to Connection Migration
+     *
      * An endpoint only changes the address to which it sends packets in
      * response to the highest-numbered non-probing packet.
      */
@@ -486,6 +497,8 @@ ngx_quic_handle_migration(ngx_connection_t *c, ngx_quic_header_t *pkt)
     ngx_quic_set_connection_path(c, next);
 
     /*
+     * RFC 9000, 9.5.  Privacy Implications of Connection Migration
+     *
      * An endpoint MUST NOT reuse a connection ID when sending to
      * more than one destination address.
      */
@@ -578,6 +591,8 @@ ngx_quic_send_path_challenge(ngx_connection_t *c, ngx_quic_path_t *path)
     ngx_memcpy(frame.u.path_challenge.data, path->challenge1, 8);
 
     /*
+     * RFC 9000, 8.2.1.  Initiating Path Validation
+     *
      * An endpoint MUST expand datagrams that contain a PATH_CHALLENGE frame
      * to at least the smallest allowed maximum datagram size of 1200 bytes,
      * unless the anti-amplification limit for the path does not permit
@@ -675,9 +690,11 @@ ngx_quic_path_validation_handler(ngx_event_t *ev)
         path->state = NGX_QUIC_PATH_NEW;
 
         /*
+         * RFC 9000, 9.4.  Loss Detection and Congestion Control
+         *
          * If the timer fires before the PATH_RESPONSE is received, the
-         * endpoint might send a new PATH_CHALLENGE, and restart the timer for
-         * a longer period of time. This timer SHOULD be set as described in
+         * endpoint might send a new PATH_CHALLENGE and restart the timer for
+         * a longer period of time.  This timer SHOULD be set as described in
          * Section 6.2.1 of [QUIC-RECOVERY] and MUST NOT be more aggressive.
          */
 
@@ -708,9 +725,13 @@ ngx_quic_path_restore(ngx_connection_t *c)
 
     qc = ngx_quic_get_connection(c);
 
-    /* Failure to validate a path does not cause the connection to end */
-
     /*
+     * RFC 9000, 9.1.  Probing a New Path
+     *
+     * Failure to validate a path does not cause the connection to end
+     *
+     * RFC 9000, 9.3.2.  On-Path Address Spoofing
+     *
      * To protect the connection from failing due to such a spurious
      * migration, an endpoint MUST revert to using the last validated
      * peer address when validation of a new peer address fails.
diff --git a/src/event/quic/ngx_event_quic_output.c b/src/event/quic/ngx_event_quic_output.c
index d6085db8b..26b046b14 100644
--- a/src/event/quic/ngx_event_quic_output.c
+++ b/src/event/quic/ngx_event_quic_output.c
@@ -23,9 +23,11 @@
     /* 1 flags + 4 version + 3 x (1 + 20) s/o/dcid + itag + token(64) */
 
 /*
+ * RFC 9000, 10.3.  Stateless Reset
+ *
  * Endpoints MUST discard packets that are too small to be valid QUIC
  * packets.  With the set of AEAD functions defined in [QUIC-TLS],
- * packets that are smaller than 21 bytes are never valid.
+ * short header packets that are smaller than 21 bytes are never valid.
  */
 #define NGX_QUIC_MIN_PKT_LEN             21
 
@@ -170,11 +172,11 @@ ngx_quic_get_padding_level(ngx_connection_t *c)
     ngx_quic_connection_t  *qc;
 
     /*
-     * 14.1.  Initial Datagram Size
+     * RFC 9000, 14.1.  Initial Datagram Size
      *
      * Similarly, a server MUST expand the payload of all UDP datagrams
      * carrying ack-eliciting Initial packets to at least the smallest
-     * allowed maximum datagram size of 1200 bytes
+     * allowed maximum datagram size of 1200 bytes.
      */
 
     qc = ngx_quic_get_connection(c);
@@ -345,6 +347,8 @@ ngx_quic_output_packet(ngx_connection_t *c, ngx_quic_send_ctx_t *ctx,
                + ngx_quic_create_header(&pkt, NULL, out.len, NULL);
 
         /*
+         * RFC 9000, 8.2.1.  Initiating Path Validation
+         *
          * An endpoint MUST expand datagrams that contain a
          * PATH_CHALLENGE frame to at least the smallest allowed
          * maximum datagram size of 1200 bytes, unless the
@@ -777,7 +781,9 @@ ngx_quic_send_retry(ngx_connection_t *c, ngx_quic_conf_t *conf,
                    "quic retry packet sent to %xV", &pkt.dcid);
 
     /*
-     * quic-transport 17.2.5.1:  A server MUST NOT send more than one Retry
+     * RFC 9000, 17.2.5.1.  Sending a Retry Packet
+     *
+     * A server MUST NOT send more than one Retry
      * packet in response to a single UDP datagram.
      * NGX_DONE will stop quic_input() from processing further
      */
diff --git a/src/event/quic/ngx_event_quic_protection.c b/src/event/quic/ngx_event_quic_protection.c
index d1801d05f..82db65921 100644
--- a/src/event/quic/ngx_event_quic_protection.c
+++ b/src/event/quic/ngx_event_quic_protection.c
@@ -160,7 +160,12 @@ ngx_quic_keys_set_initial_secret(ngx_pool_t *pool, ngx_quic_keys_t *keys,
     client = &keys->secrets[ssl_encryption_initial].client;
     server = &keys->secrets[ssl_encryption_initial].server;
 
-    /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.3 */
+    /*
+     * RFC 9001, section 5.  Packet Protection
+     *
+     * Initial packets use AEAD_AES_128_GCM.  The hash function
+     * for HKDF when deriving initial secrets and keys is SHA-256.
+     */
 
     cipher = EVP_aes_128_gcm();
     digest = EVP_sha256();
@@ -187,7 +192,6 @@ ngx_quic_keys_set_initial_secret(ngx_pool_t *pool, ngx_quic_keys_t *keys,
                    "quic initial secret len:%uz %*xs", is_len, is_len, is);
 #endif
 
-    /* draft-ietf-quic-tls-23#section-5.2 */
     client->secret.len = SHA256_DIGEST_LENGTH;
     server->secret.len = SHA256_DIGEST_LENGTH;
 
@@ -206,7 +210,7 @@ ngx_quic_keys_set_initial_secret(ngx_pool_t *pool, ngx_quic_keys_t *keys,
         ngx_str_t  *prk;
     } seq[] = {
 
-        /* draft-ietf-quic-tls-23#section-5.2 */
+        /* labels per RFC 9001, 5.1. Packet Protection Keys */
         { ngx_string("tls13 client in"), &client->secret, &iss },
         {
             ngx_string("tls13 quic key"),
@@ -219,14 +223,12 @@ ngx_quic_keys_set_initial_secret(ngx_pool_t *pool, ngx_quic_keys_t *keys,
             &client->secret,
         },
         {
-            /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.4.1 */
             ngx_string("tls13 quic hp"),
             &client->hp,
             &client->secret,
         },
         { ngx_string("tls13 server in"), &server->secret, &iss },
         {
-            /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.3 */
             ngx_string("tls13 quic key"),
             &server->key,
             &server->secret,
@@ -237,7 +239,6 @@ ngx_quic_keys_set_initial_secret(ngx_pool_t *pool, ngx_quic_keys_t *keys,
             &server->secret,
         },
         {
-            /* AEAD_AES_128_GCM prior to handshake, quic-tls-23#section-5.4.1 */
             ngx_string("tls13 quic hp"),
             &server->hp,
             &server->secret,
@@ -894,7 +895,7 @@ ngx_quic_create_packet(ngx_quic_header_t *pkt, ngx_str_t *res)
         return NGX_ERROR;
     }
 
-    /* quic-tls: 5.4.1.  Header Protection Application */
+    /* RFC 9001, 5.4.1.  Header Protection Application */
     ad.data[0] ^= mask[0] & ngx_quic_pkt_hp_mask(pkt->flags);
 
     for (i = 0; i < pkt->num_len; i++) {
@@ -1095,10 +1096,13 @@ ngx_quic_decrypt(ngx_quic_header_t *pkt, uint64_t *largest_pn)
     p = pkt->raw->pos;
     len = pkt->data + pkt->len - p;
 
-    /* draft-ietf-quic-tls-23#section-5.4.2:
+    /*
+     * RFC 9001, 5.4.2. Header Protection Sample
+     *           5.4.3. AES-Based Header Protection
+     *           5.4.4. ChaCha20-Based Header Protection
+     *
      * the Packet Number field is assumed to be 4 bytes long
-     * draft-ietf-quic-tls-23#section-5.4.[34]:
-     * AES-Based and ChaCha20-Based header protections sample 16 bytes
+     * AES and ChaCha20 algorithms sample 16 bytes
      */
 
     if (len < EVP_GCM_TLS_TAG_LEN + 4) {
@@ -1172,6 +1176,8 @@ ngx_quic_decrypt(ngx_quic_header_t *pkt, uint64_t *largest_pn)
 
     if (pkt->payload.len == 0) {
         /*
+         * RFC 9000, 12.4.  Frames and Frame Types
+         *
          * An endpoint MUST treat receipt of a packet containing no
          * frames as a connection error of type PROTOCOL_VIOLATION.
          */
@@ -1182,6 +1188,8 @@ ngx_quic_decrypt(ngx_quic_header_t *pkt, uint64_t *largest_pn)
 
     if (pkt->flags & ngx_quic_pkt_rb_mask(pkt->flags)) {
         /*
+         * RFC 9000, Reserved Bits
+         *
          * An endpoint MUST treat receipt of a packet that has
          * a non-zero value for these bits, after removing both
          * packet and header protection, as a connection error
diff --git a/src/event/quic/ngx_event_quic_ssl.c b/src/event/quic/ngx_event_quic_ssl.c
index 1ee687b38..5e2827f23 100644
--- a/src/event/quic/ngx_event_quic_ssl.c
+++ b/src/event/quic/ngx_event_quic_ssl.c
@@ -11,8 +11,9 @@
 
 
 /*
- * 7.4.  Cryptographic Message Buffering
- *       Implementations MUST support buffering at least 4096 bytes of data
+ * RFC 9000, 7.5.  Cryptographic Message Buffering
+ *
+ * Implementations MUST support buffering at least 4096 bytes of data
  */
 #define NGX_QUIC_MAX_BUFFERED    65535
 
@@ -198,7 +199,7 @@ ngx_quic_add_handshake_data(ngx_ssl_conn_t *ssl_conn,
                        " params_len:%ui", client_params_len);
 
         if (client_params_len == 0) {
-            /* quic-tls 8.2 */
+            /* RFC 9001, 8.2.  QUIC Transport Parameters Extension */
             qc->error = NGX_QUIC_ERR_CRYPTO(SSL_AD_MISSING_EXTENSION);
             qc->error_reason = "missing transport parameters";
 
@@ -428,7 +429,6 @@ ngx_quic_crypto_input(ngx_connection_t *c, ngx_chain_t *data)
         return NGX_ERROR;
     }
 
-    /* 12.4 Frames and frame types, figure 8 */
     frame->level = ssl_encryption_application;
     frame->type = NGX_QUIC_FT_HANDSHAKE_DONE;
     ngx_quic_queue_frame(qc, frame);
@@ -440,8 +440,9 @@ ngx_quic_crypto_input(ngx_connection_t *c, ngx_chain_t *data)
     }
 
     /*
+     * RFC 9001, 9.5.  Header Protection Timing Side Channels
+     *
      * Generating next keys before a key update is received.
-     * See quic-tls 9.4 Header Protection Timing Side-Channels.
      */
 
     if (ngx_quic_keys_update(c, qc->keys) != NGX_OK) {
@@ -449,8 +450,10 @@ ngx_quic_crypto_input(ngx_connection_t *c, ngx_chain_t *data)
     }
 
     /*
-     * 4.10.2 An endpoint MUST discard its handshake keys
-     * when the TLS handshake is confirmed
+     * RFC 9001, 4.9.2.  Discarding Handshake Keys
+     *
+     * An endpoint MUST discard its Handshake keys
+     * when the TLS handshake is confirmed.
      */
     ngx_quic_discard_ctx(c, ssl_encryption_handshake);
 
diff --git a/src/event/quic/ngx_event_quic_streams.c b/src/event/quic/ngx_event_quic_streams.c
index c6f02a37f..24ccdea03 100644
--- a/src/event/quic/ngx_event_quic_streams.c
+++ b/src/event/quic/ngx_event_quic_streams.c
@@ -296,12 +296,11 @@ ngx_quic_create_client_stream(ngx_connection_t *c, uint64_t id)
     }
 
     /*
-     *   2.1.  Stream Types and Identifiers
+     * RFC 9000, 2.1.  Stream Types and Identifiers
      *
-     *   Within each type, streams are created with numerically increasing
-     *   stream IDs.  A stream ID that is used out of order results in all
-     *   streams of that type with lower-numbered stream IDs also being
-     *   opened.
+     * successive streams of each type are created with numerically increasing
+     * stream IDs.  A stream ID that is used out of order results in all
+     * streams of that type with lower-numbered stream IDs also being opened.
      */
 
     for ( /* void */ ; min_id < id; min_id += 0x04) {
diff --git a/src/event/quic/ngx_event_quic_transport.c b/src/event/quic/ngx_event_quic_transport.c
index c13155c55..894595fbc 100644
--- a/src/event/quic/ngx_event_quic_transport.c
+++ b/src/event/quic/ngx_event_quic_transport.c
@@ -1127,7 +1127,11 @@ ngx_quic_frame_allowed(ngx_quic_header_t *pkt, ngx_uint_t frame_type)
 {
     uint8_t  ptype;
 
-    /* frame permissions per packet: 4 bits: IH01: 12.4, Table 3 */
+    /*
+     * RFC 9000, 12.4. Frames and Frame Types: Table 3
+     *
+     * Frame permissions per packet: 4 bits: IH01
+     */
     static uint8_t ngx_quic_frame_masks[] = {
          /* PADDING  */              0xF,
          /* PING */                  0xF,
@@ -1242,9 +1246,9 @@ ssize_t
 ngx_quic_create_frame(u_char *p, ngx_quic_frame_t *f)
 {
     /*
-     *  QUIC-recovery, section 2:
+     *  RFC 9002, 2.  Conventions and Definitions
      *
-     *  Ack-eliciting Frames:  All frames other than ACK, PADDING, and
+     *  Ack-eliciting frames:  All frames other than ACK, PADDING, and
      *  CONNECTION_CLOSE are considered ack-eliciting.
      */
     f->need_ack = 1;
diff --git a/src/event/quic/ngx_event_quic_transport.h b/src/event/quic/ngx_event_quic_transport.h
index 9fb621721..b35ba1839 100644
--- a/src/event/quic/ngx_event_quic_transport.h
+++ b/src/event/quic/ngx_event_quic_transport.h
@@ -12,8 +12,12 @@
 #include <ngx_core.h>
 
 
-/* QUIC flags in first byte, see quic-transport 17.2 and 17.3 */
-
+/*
+ * RFC 9000, 17.2.  Long Header Packets
+ *           17.3.  Short Header Packets
+ *
+ * QUIC flags in first byte
+ */
 #define NGX_QUIC_PKT_LONG       0x80  /* header form */
 #define NGX_QUIC_PKT_FIXED_BIT  0x40
 #define NGX_QUIC_PKT_TYPE       0x30  /* in long packet */
@@ -85,7 +89,7 @@
 
 #define NGX_QUIC_FT_LAST  NGX_QUIC_FT_HANDSHAKE_DONE
 
-/* 22.4.  QUIC Transport Error Codes Registry */
+/* 22.5.  QUIC Transport Error Codes Registry */
 /* Keep in sync with ngx_quic_errors[] */
 #define NGX_QUIC_ERR_NO_ERROR                            0x00
 #define NGX_QUIC_ERR_INTERNAL_ERROR                      0x01
@@ -111,7 +115,7 @@
 #define NGX_QUIC_ERR_CRYPTO(e)  (NGX_QUIC_ERR_CRYPTO_ERROR + (e))
 
 
-/* Transport parameters */
+/* 22.3.  QUIC Transport Parameters Registry */
 #define NGX_QUIC_TP_ORIGINAL_DCID                        0x00
 #define NGX_QUIC_TP_MAX_IDLE_TIMEOUT                     0x01
 #define NGX_QUIC_TP_SR_TOKEN                             0x02