Mercurial > hg > nginx-quic
view src/stream/ngx_stream_return_module.c @ 8743:5d09596909c6 stable-1.20
Upstream: fixed timeouts with gRPC, SSL and select (ticket #2229).
With SSL it is possible that an established connection is ready for
reading after the handshake. Further, events might be already disabled
in case of level-triggered event methods. If this happens and
ngx_http_upstream_send_request() blocks waiting for some data from
the upstream, such as flow control in case of gRPC, the connection
will time out due to no read events on the upstream connection.
Fix is to explicitly check the c->read->ready flag if sending request
blocks and post a read event if it is set.
Note that while it is possible to modify ngx_ssl_handshake() to keep
read events active, this won't completely resolve the issue, since
there can be data already received during the SSL handshake
(see 573bd30e46b4).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Fri, 20 Aug 2021 03:53:56 +0300 |
parents | 56fc55e32f23 |
children |
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/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> typedef struct { ngx_stream_complex_value_t text; } ngx_stream_return_srv_conf_t; typedef struct { ngx_chain_t *out; } ngx_stream_return_ctx_t; static void ngx_stream_return_handler(ngx_stream_session_t *s); static void ngx_stream_return_write_handler(ngx_event_t *ev); static void *ngx_stream_return_create_srv_conf(ngx_conf_t *cf); static char *ngx_stream_return(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_stream_return_commands[] = { { ngx_string("return"), NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1, ngx_stream_return, NGX_STREAM_SRV_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_return_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_stream_return_create_srv_conf, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_return_module = { NGX_MODULE_V1, &ngx_stream_return_module_ctx, /* module context */ ngx_stream_return_commands, /* module directives */ NGX_STREAM_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static void ngx_stream_return_handler(ngx_stream_session_t *s) { ngx_str_t text; ngx_buf_t *b; ngx_connection_t *c; ngx_stream_return_ctx_t *ctx; ngx_stream_return_srv_conf_t *rscf; c = s->connection; c->log->action = "returning text"; rscf = ngx_stream_get_module_srv_conf(s, ngx_stream_return_module); if (ngx_stream_complex_value(s, &rscf->text, &text) != NGX_OK) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ngx_log_debug1(NGX_LOG_DEBUG_STREAM, c->log, 0, "stream return text: \"%V\"", &text); if (text.len == 0) { ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } ctx = ngx_pcalloc(c->pool, sizeof(ngx_stream_return_ctx_t)); if (ctx == NULL) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ngx_stream_set_ctx(s, ctx, ngx_stream_return_module); b = ngx_calloc_buf(c->pool); if (b == NULL) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } b->memory = 1; b->pos = text.data; b->last = text.data + text.len; b->last_buf = 1; ctx->out = ngx_alloc_chain_link(c->pool); if (ctx->out == NULL) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ctx->out->buf = b; ctx->out->next = NULL; c->write->handler = ngx_stream_return_write_handler; ngx_stream_return_write_handler(c->write); } static void ngx_stream_return_write_handler(ngx_event_t *ev) { ngx_connection_t *c; ngx_stream_session_t *s; ngx_stream_return_ctx_t *ctx; c = ev->data; s = c->data; if (ev->timedout) { ngx_connection_error(c, NGX_ETIMEDOUT, "connection timed out"); ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } ctx = ngx_stream_get_module_ctx(s, ngx_stream_return_module); if (ngx_stream_top_filter(s, ctx->out, 1) == NGX_ERROR) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ctx->out = NULL; if (!c->buffered) { ngx_log_debug0(NGX_LOG_DEBUG_STREAM, c->log, 0, "stream return done sending"); ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } if (ngx_handle_write_event(ev, 0) != NGX_OK) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ngx_add_timer(ev, 5000); } static void * ngx_stream_return_create_srv_conf(ngx_conf_t *cf) { ngx_stream_return_srv_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_return_srv_conf_t)); if (conf == NULL) { return NULL; } return conf; } static char * ngx_stream_return(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_stream_return_srv_conf_t *rscf = conf; ngx_str_t *value; ngx_stream_core_srv_conf_t *cscf; ngx_stream_compile_complex_value_t ccv; if (rscf->text.value.data) { return "is duplicate"; } value = cf->args->elts; ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t)); ccv.cf = cf; ccv.value = &value[1]; ccv.complex_value = &rscf->text; if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } cscf = ngx_stream_conf_get_module_srv_conf(cf, ngx_stream_core_module); cscf->handler = ngx_stream_return_handler; return NGX_CONF_OK; }