details: http://hg.nginx.org/nginx/rev/12cadc4669a7 branches: changeset: 7100:12cadc4669a7 user: Piotr Sikora <[email protected]> date: Wed Aug 30 14:52:11 2017 -0700 description: HTTP/2: signal 0-byte HPACK's dynamic table size.
This change lets NGINX talk to clients with SETTINGS_HEADER_TABLE_SIZE smaller than the default 4KB. Previously, NGINX would ACK the SETTINGS frame with a small dynamic table size, but it would never send dynamic table size update, leading to a connection-level COMPRESSION_ERROR. Also, it allows clients to release 4KB of memory per connection, since NGINX doesn't use HPACK's dynamic table when encoding headers, however clients had to maintain it, since NGINX never signaled that it doesn't use it. Signed-off-by: Piotr Sikora <[email protected]> diffstat: src/http/v2/ngx_http_v2.c | 2 ++ src/http/v2/ngx_http_v2.h | 1 + src/http/v2/ngx_http_v2_filter_module.c | 14 +++++++++++++- 3 files changed, 16 insertions(+), 1 deletions(-) diffs (61 lines): diff --git a/src/http/v2/ngx_http_v2.c b/src/http/v2/ngx_http_v2.c --- a/src/http/v2/ngx_http_v2.c +++ b/src/http/v2/ngx_http_v2.c @@ -245,6 +245,8 @@ ngx_http_v2_init(ngx_event_t *rev) h2c->frame_size = NGX_HTTP_V2_DEFAULT_FRAME_SIZE; + h2c->table_update = 1; + h2scf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module); h2c->pool = ngx_create_pool(h2scf->pool_size, h2c->connection->log); diff --git a/src/http/v2/ngx_http_v2.h b/src/http/v2/ngx_http_v2.h --- a/src/http/v2/ngx_http_v2.h +++ b/src/http/v2/ngx_http_v2.h @@ -144,6 +144,7 @@ struct ngx_http_v2_connection_s { unsigned closed_nodes:8; unsigned settings_ack:1; + unsigned table_update:1; unsigned blocked:1; unsigned goaway:1; }; diff --git a/src/http/v2/ngx_http_v2_filter_module.c b/src/http/v2/ngx_http_v2_filter_module.c --- a/src/http/v2/ngx_http_v2_filter_module.c +++ b/src/http/v2/ngx_http_v2_filter_module.c @@ -139,6 +139,7 @@ ngx_http_v2_header_filter(ngx_http_reque ngx_connection_t *fc; ngx_http_cleanup_t *cln; ngx_http_v2_out_frame_t *frame; + ngx_http_v2_connection_t *h2c; ngx_http_core_loc_conf_t *clcf; ngx_http_core_srv_conf_t *cscf; u_char addr[NGX_SOCKADDR_STRLEN]; @@ -235,7 +236,11 @@ ngx_http_v2_header_filter(ngx_http_reque } } - len = status ? 1 : 1 + ngx_http_v2_literal_size("418"); + h2c = r->stream->connection; + + len = h2c->table_update ? 1 : 0; + + len += status ? 1 : 1 + ngx_http_v2_literal_size("418"); clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); @@ -423,6 +428,13 @@ ngx_http_v2_header_filter(ngx_http_reque start = pos; + if (h2c->table_update) { + ngx_log_debug0(NGX_LOG_DEBUG_HTTP, fc->log, 0, + "http2 table size update: 0"); + *pos++ = (1 << 5) | 0; + h2c->table_update = 0; + } + ngx_log_debug1(NGX_LOG_DEBUG_HTTP, fc->log, 0, "http2 output header: \":status: %03ui\"", r->headers_out.status); _______________________________________________ nginx-devel mailing list [email protected] http://mailman.nginx.org/mailman/listinfo/nginx-devel
