--- src/event/ngx_event_openssl.c.orig 2021-04-20 13:35:47 UTC +++ src/event/ngx_event_openssl.c @@ -1616,6 +1616,7 @@ ngx_ssl_create_connection(ngx_ssl_t *ssl sc->buffer = ((flags & NGX_SSL_BUFFER) != 0); sc->buffer_size = ssl->buffer_size; + sc->dyn_rec = ssl->dyn_rec; sc->session_ctx = ssl->ctx; @@ -2555,6 +2556,41 @@ ngx_ssl_send_chain(ngx_connection_t *c, for ( ;; ) { + /* Dynamic record resizing: + We want the initial records to fit into one TCP segment + so we don't get TCP HoL blocking due to TCP Slow Start. + A connection always starts with small records, but after + a given amount of records sent, we make the records larger + to reduce header overhead. + After a connection has idled for a given timeout, begin + the process from the start. The actual parameters are + configurable. If dyn_rec_timeout is 0, we assume dyn_rec is off. */ + + if (c->ssl->dyn_rec.timeout > 0 ) { + + if (ngx_current_msec - c->ssl->dyn_rec_last_write > + c->ssl->dyn_rec.timeout) + { + buf->end = buf->start + c->ssl->dyn_rec.size_lo; + c->ssl->dyn_rec_records_sent = 0; + + } else { + if (c->ssl->dyn_rec_records_sent > + c->ssl->dyn_rec.threshold * 2) + { + buf->end = buf->start + c->ssl->buffer_size; + + } else if (c->ssl->dyn_rec_records_sent > + c->ssl->dyn_rec.threshold) + { + buf->end = buf->start + c->ssl->dyn_rec.size_hi; + + } else { + buf->end = buf->start + c->ssl->dyn_rec.size_lo; + } + } + } + while (in && buf->last < buf->end && send < limit) { if (in->buf->last_buf || in->buf->flush) { flush = 1; @@ -2662,6 +2698,9 @@ ngx_ssl_write(ngx_connection_t *c, u_cha if (n > 0) { + c->ssl->dyn_rec_records_sent++; + c->ssl->dyn_rec_last_write = ngx_current_msec; + if (c->ssl->saved_read_handler) { c->read->handler = c->ssl->saved_read_handler; --- src/event/ngx_event_openssl.h.orig 2021-04-20 13:35:47 UTC +++ src/event/ngx_event_openssl.h @@ -66,11 +66,19 @@ typedef struct ngx_ssl_ocsp_s ngx_ssl_ocsp_t; +typedef struct { + ngx_msec_t timeout; + ngx_uint_t threshold; + size_t size_lo; + size_t size_hi; +} ngx_ssl_dyn_rec_t; + struct ngx_ssl_s { SSL_CTX *ctx; ngx_log_t *log; size_t buffer_size; + ngx_ssl_dyn_rec_t dyn_rec; }; @@ -106,6 +114,10 @@ struct ngx_ssl_connection_s { unsigned in_ocsp:1; unsigned early_preread:1; unsigned write_blocked:1; + + ngx_ssl_dyn_rec_t dyn_rec; + ngx_msec_t dyn_rec_last_write; + ngx_uint_t dyn_rec_records_sent; }; @@ -115,7 +127,7 @@ struct ngx_ssl_connection_s { #define NGX_SSL_DFLT_BUILTIN_SCACHE -5 -#define NGX_SSL_MAX_SESSION_SIZE 4096 +#define NGX_SSL_MAX_SESSION_SIZE 16384 typedef struct ngx_ssl_sess_id_s ngx_ssl_sess_id_t; --- src/http/modules/ngx_http_ssl_module.c.orig 2021-04-20 13:35:47 UTC +++ src/http/modules/ngx_http_ssl_module.c @@ -301,6 +301,41 @@ static ngx_command_t ngx_http_ssl_comma offsetof(ngx_http_ssl_srv_conf_t, reject_handshake), NULL }, + { ngx_string("ssl_dyn_rec_enable"), + NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG, + ngx_conf_set_flag_slot, + NGX_HTTP_SRV_CONF_OFFSET, + offsetof(ngx_http_ssl_srv_conf_t, dyn_rec_enable), + NULL }, + + { ngx_string("ssl_dyn_rec_timeout"), + NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG, + ngx_conf_set_msec_slot, + NGX_HTTP_SRV_CONF_OFFSET, + offsetof(ngx_http_ssl_srv_conf_t, dyn_rec_timeout), + NULL }, + + { ngx_string("ssl_dyn_rec_size_lo"), + NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG, + ngx_conf_set_size_slot, + NGX_HTTP_SRV_CONF_OFFSET, + offsetof(ngx_http_ssl_srv_conf_t, dyn_rec_size_lo), + NULL }, + + { ngx_string("ssl_dyn_rec_size_hi"), + NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG, + ngx_conf_set_size_slot, + NGX_HTTP_SRV_CONF_OFFSET, + offsetof(ngx_http_ssl_srv_conf_t, dyn_rec_size_hi), + NULL }, + + { ngx_string("ssl_dyn_rec_threshold"), + NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG, + ngx_conf_set_num_slot, + NGX_HTTP_SRV_CONF_OFFSET, + offsetof(ngx_http_ssl_srv_conf_t, dyn_rec_threshold), + NULL }, + ngx_null_command }; @@ -637,6 +672,11 @@ ngx_http_ssl_create_srv_conf(ngx_conf_t sscf->ocsp_cache_zone = NGX_CONF_UNSET_PTR; sscf->stapling = NGX_CONF_UNSET; sscf->stapling_verify = NGX_CONF_UNSET; + sscf->dyn_rec_enable = NGX_CONF_UNSET; + sscf->dyn_rec_timeout = NGX_CONF_UNSET_MSEC; + sscf->dyn_rec_size_lo = NGX_CONF_UNSET_SIZE; + sscf->dyn_rec_size_hi = NGX_CONF_UNSET_SIZE; + sscf->dyn_rec_threshold = NGX_CONF_UNSET_UINT; return sscf; } @@ -712,6 +752,20 @@ ngx_http_ssl_merge_srv_conf(ngx_conf_t * ngx_conf_merge_str_value(conf->stapling_responder, prev->stapling_responder, ""); + ngx_conf_merge_value(conf->dyn_rec_enable, prev->dyn_rec_enable, 0); + ngx_conf_merge_msec_value(conf->dyn_rec_timeout, prev->dyn_rec_timeout, + 1000); + /* Default sizes for the dynamic record sizes are defined to fit maximal + TLS + IPv6 overhead in a single TCP segment for lo and 3 segments for hi: + 1369 = 1500 - 40 (IP) - 20 (TCP) - 10 (Time) - 61 (Max TLS overhead) */ + ngx_conf_merge_size_value(conf->dyn_rec_size_lo, prev->dyn_rec_size_lo, + 1369); + /* 4229 = (1500 - 40 - 20 - 10) * 3 - 61 */ + ngx_conf_merge_size_value(conf->dyn_rec_size_hi, prev->dyn_rec_size_hi, + 4229); + ngx_conf_merge_uint_value(conf->dyn_rec_threshold, prev->dyn_rec_threshold, + 40); + conf->ssl.log = cf->log; if (conf->enable) { @@ -943,6 +997,28 @@ ngx_http_ssl_merge_srv_conf(ngx_conf_t * return NGX_CONF_ERROR; } + if (conf->dyn_rec_enable) { + conf->ssl.dyn_rec.timeout = conf->dyn_rec_timeout; + conf->ssl.dyn_rec.threshold = conf->dyn_rec_threshold; + + if (conf->buffer_size > conf->dyn_rec_size_lo) { + conf->ssl.dyn_rec.size_lo = conf->dyn_rec_size_lo; + + } else { + conf->ssl.dyn_rec.size_lo = conf->buffer_size; + } + + if (conf->buffer_size > conf->dyn_rec_size_hi) { + conf->ssl.dyn_rec.size_hi = conf->dyn_rec_size_hi; + + } else { + conf->ssl.dyn_rec.size_hi = conf->buffer_size; + } + + } else { + conf->ssl.dyn_rec.timeout = 0; + } + return NGX_CONF_OK; } --- src/http/modules/ngx_http_ssl_module.h.orig 2021-04-20 13:35:47 UTC +++ src/http/modules/ngx_http_ssl_module.h @@ -67,6 +67,12 @@ typedef struct { u_char *file; ngx_uint_t line; + + ngx_flag_t dyn_rec_enable; + ngx_msec_t dyn_rec_timeout; + size_t dyn_rec_size_lo; + size_t dyn_rec_size_hi; + ngx_uint_t dyn_rec_threshold; } ngx_http_ssl_srv_conf_t;