Mercurial > hg > nginx
changeset 9165:cdda286c0f1b
HTTP/2: per-iteration stream handling limit.
To ensure that attempts to flood servers with many streams are detected
early, a limit of no more than 2 * max_concurrent_streams new streams per one
event loop iteration was introduced. This limit is applied even if
max_concurrent_streams is not yet reached - for example, if corresponding
streams are handled synchronously or reset.
Further, refused streams are now limited to maximum of max_concurrent_streams
and 100, similarly to priority_limit initial value, providing some tolerance
to clients trying to open several streams at the connection start, yet
low tolerance to flooding attempts.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Tue, 10 Oct 2023 15:13:39 +0300 |
parents | 3db945fda515 |
children | 533bc2336df4 |
files | src/http/v2/ngx_http_v2.c src/http/v2/ngx_http_v2.h |
diffstat | 2 files changed, 17 insertions(+), 0 deletions(-) [+] |
line wrap: on
line diff
--- a/src/http/v2/ngx_http_v2.c Fri Sep 22 19:23:57 2023 +0400 +++ b/src/http/v2/ngx_http_v2.c Tue Oct 10 15:13:39 2023 +0300 @@ -347,6 +347,7 @@ ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http2 read handler"); h2c->blocked = 1; + h2c->new_streams = 0; if (c->close) { c->close = 0; @@ -1284,6 +1285,14 @@ goto rst_stream; } + if (h2c->new_streams++ >= 2 * h2scf->concurrent_streams) { + ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0, + "client sent too many streams at once"); + + status = NGX_HTTP_V2_REFUSED_STREAM; + goto rst_stream; + } + if (!h2c->settings_ack && !(h2c->state.flags & NGX_HTTP_V2_END_STREAM_FLAG) && h2scf->preread_size < NGX_HTTP_V2_DEFAULT_WINDOW) @@ -1349,6 +1358,12 @@ rst_stream: + if (h2c->refused_streams++ > ngx_max(h2scf->concurrent_streams, 100)) { + ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0, + "client sent too many refused streams"); + return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_NO_ERROR); + } + if (ngx_http_v2_send_rst_stream(h2c, h2c->state.sid, status) != NGX_OK) { return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR); }
--- a/src/http/v2/ngx_http_v2.h Fri Sep 22 19:23:57 2023 +0400 +++ b/src/http/v2/ngx_http_v2.h Tue Oct 10 15:13:39 2023 +0300 @@ -131,6 +131,8 @@ ngx_uint_t processing; ngx_uint_t frames; ngx_uint_t idle; + ngx_uint_t new_streams; + ngx_uint_t refused_streams; ngx_uint_t priority_limit; size_t send_window;