From fffd2823ba8bddcdfdffca47990c73cd4298208d Mon Sep 17 00:00:00 2001 From: Sergey Kandaurov Date: Fri, 20 Oct 2023 18:05:07 +0400 Subject: [PATCH] QUIC: added safety belt to prevent using discarded keys. In addition to triggering alert, it ensures that such packets won't be sent. With the previous change that marks server keys as discarded by zeroing the key lengh, it is now an error to send packets with discarded keys. OpenSSL based stacks tolerate such behaviour because key length isn't used in packet protection, but BoringSSL will raise the UNSUPPORTED_KEY_SIZE cipher error. It won't be possible to use discarded keys with reused crypto contexts as it happens in subsequent changes. --- src/event/quic/ngx_event_quic_output.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/src/event/quic/ngx_event_quic_output.c b/src/event/quic/ngx_event_quic_output.c index 587671bc6..bd3e7e3b0 100644 --- a/src/event/quic/ngx_event_quic_output.c +++ b/src/event/quic/ngx_event_quic_output.c @@ -519,6 +519,21 @@ ngx_quic_output_packet(ngx_connection_t *c, ngx_quic_send_ctx_t *ctx, qc = ngx_quic_get_connection(c); + if (!ngx_quic_keys_available(qc->keys, ctx->level, 1)) { + ngx_log_error(NGX_LOG_ALERT, c->log, 0, "quic %s write keys discarded", + ngx_quic_level_name(ctx->level)); + + while (!ngx_queue_empty(&ctx->frames)) { + q = ngx_queue_head(&ctx->frames); + ngx_queue_remove(q); + + f = ngx_queue_data(q, ngx_quic_frame_t, queue); + ngx_quic_free_frame(c, f); + } + + return 0; + } + ngx_quic_init_packet(c, ctx, &pkt, qc->path); min_payload = ngx_quic_payload_size(&pkt, min);