Mercurial > hg > nginx
view src/http/modules/ngx_http_upstream_keepalive_module.c @ 7235:c2a0a838c40f
gRPC: special handling of "trailer only" responses.
The gRPC protocol makes a distinction between HEADERS frame with
the END_STREAM flag set, and a HEADERS frame followed by an empty
DATA frame with the END_STREAM flag. The latter is not permitted,
and results in errors not being propagated through nginx. Instead,
gRPC clients complain that "server closed the stream without sending
trailers" (seen in grpc-go) or "13: Received RST_STREAM with error
code 2" (seen in grpc-c).
To fix this, nginx now returns HEADERS with the END_STREAM flag if
the response length is known to be 0, and we are not expecting
any trailer headers to be added. And the response length is
explicitly set to 0 in the gRPC proxy if we see initial HEADERS frame
with the END_STREAM flag set.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Sat, 17 Mar 2018 23:04:26 +0300 |
parents | 1cb92a2d672e |
children | 46174066b75f |
line wrap: on
line source
/* * Copyright (C) Maxim Dounin * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_uint_t max_cached; ngx_queue_t cache; ngx_queue_t free; ngx_http_upstream_init_pt original_init_upstream; ngx_http_upstream_init_peer_pt original_init_peer; } ngx_http_upstream_keepalive_srv_conf_t; typedef struct { ngx_http_upstream_keepalive_srv_conf_t *conf; ngx_queue_t queue; ngx_connection_t *connection; socklen_t socklen; ngx_sockaddr_t sockaddr; } ngx_http_upstream_keepalive_cache_t; typedef struct { ngx_http_upstream_keepalive_srv_conf_t *conf; ngx_http_upstream_t *upstream; void *data; ngx_event_get_peer_pt original_get_peer; ngx_event_free_peer_pt original_free_peer; #if (NGX_HTTP_SSL) ngx_event_set_peer_session_pt original_set_session; ngx_event_save_peer_session_pt original_save_session; #endif } ngx_http_upstream_keepalive_peer_data_t; static ngx_int_t ngx_http_upstream_init_keepalive_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us); static ngx_int_t ngx_http_upstream_get_keepalive_peer(ngx_peer_connection_t *pc, void *data); static void ngx_http_upstream_free_keepalive_peer(ngx_peer_connection_t *pc, void *data, ngx_uint_t state); static void ngx_http_upstream_keepalive_dummy_handler(ngx_event_t *ev); static void ngx_http_upstream_keepalive_close_handler(ngx_event_t *ev); static void ngx_http_upstream_keepalive_close(ngx_connection_t *c); #if (NGX_HTTP_SSL) static ngx_int_t ngx_http_upstream_keepalive_set_session( ngx_peer_connection_t *pc, void *data); static void ngx_http_upstream_keepalive_save_session(ngx_peer_connection_t *pc, void *data); #endif static void *ngx_http_upstream_keepalive_create_conf(ngx_conf_t *cf); static char *ngx_http_upstream_keepalive(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_http_upstream_keepalive_commands[] = { { ngx_string("keepalive"), NGX_HTTP_UPS_CONF|NGX_CONF_TAKE1, ngx_http_upstream_keepalive, NGX_HTTP_SRV_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_upstream_keepalive_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_http_upstream_keepalive_create_conf, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_upstream_keepalive_module = { NGX_MODULE_V1, &ngx_http_upstream_keepalive_module_ctx, /* module context */ ngx_http_upstream_keepalive_commands, /* module directives */ NGX_HTTP_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 ngx_int_t ngx_http_upstream_init_keepalive(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us) { ngx_uint_t i; ngx_http_upstream_keepalive_srv_conf_t *kcf; ngx_http_upstream_keepalive_cache_t *cached; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, cf->log, 0, "init keepalive"); kcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_keepalive_module); if (kcf->original_init_upstream(cf, us) != NGX_OK) { return NGX_ERROR; } kcf->original_init_peer = us->peer.init; us->peer.init = ngx_http_upstream_init_keepalive_peer; /* allocate cache items and add to free queue */ cached = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_keepalive_cache_t) * kcf->max_cached); if (cached == NULL) { return NGX_ERROR; } ngx_queue_init(&kcf->cache); ngx_queue_init(&kcf->free); for (i = 0; i < kcf->max_cached; i++) { ngx_queue_insert_head(&kcf->free, &cached[i].queue); cached[i].conf = kcf; } return NGX_OK; } static ngx_int_t ngx_http_upstream_init_keepalive_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us) { ngx_http_upstream_keepalive_peer_data_t *kp; ngx_http_upstream_keepalive_srv_conf_t *kcf; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "init keepalive peer"); kcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_keepalive_module); kp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_keepalive_peer_data_t)); if (kp == NULL) { return NGX_ERROR; } if (kcf->original_init_peer(r, us) != NGX_OK) { return NGX_ERROR; } kp->conf = kcf; kp->upstream = r->upstream; kp->data = r->upstream->peer.data; kp->original_get_peer = r->upstream->peer.get; kp->original_free_peer = r->upstream->peer.free; r->upstream->peer.data = kp; r->upstream->peer.get = ngx_http_upstream_get_keepalive_peer; r->upstream->peer.free = ngx_http_upstream_free_keepalive_peer; #if (NGX_HTTP_SSL) kp->original_set_session = r->upstream->peer.set_session; kp->original_save_session = r->upstream->peer.save_session; r->upstream->peer.set_session = ngx_http_upstream_keepalive_set_session; r->upstream->peer.save_session = ngx_http_upstream_keepalive_save_session; #endif return NGX_OK; } static ngx_int_t ngx_http_upstream_get_keepalive_peer(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_keepalive_peer_data_t *kp = data; ngx_http_upstream_keepalive_cache_t *item; ngx_int_t rc; ngx_queue_t *q, *cache; ngx_connection_t *c; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get keepalive peer"); /* ask balancer */ rc = kp->original_get_peer(pc, kp->data); if (rc != NGX_OK) { return rc; } /* search cache for suitable connection */ cache = &kp->conf->cache; for (q = ngx_queue_head(cache); q != ngx_queue_sentinel(cache); q = ngx_queue_next(q)) { item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue); c = item->connection; if (ngx_memn2cmp((u_char *) &item->sockaddr, (u_char *) pc->sockaddr, item->socklen, pc->socklen) == 0) { ngx_queue_remove(q); ngx_queue_insert_head(&kp->conf->free, q); goto found; } } return NGX_OK; found: ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get keepalive peer: using connection %p", c); c->idle = 0; c->sent = 0; c->log = pc->log; c->read->log = pc->log; c->write->log = pc->log; c->pool->log = pc->log; pc->connection = c; pc->cached = 1; return NGX_DONE; } static void ngx_http_upstream_free_keepalive_peer(ngx_peer_connection_t *pc, void *data, ngx_uint_t state) { ngx_http_upstream_keepalive_peer_data_t *kp = data; ngx_http_upstream_keepalive_cache_t *item; ngx_queue_t *q; ngx_connection_t *c; ngx_http_upstream_t *u; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0, "free keepalive peer"); /* cache valid connections */ u = kp->upstream; c = pc->connection; if (state & NGX_PEER_FAILED || c == NULL || c->read->eof || c->read->error || c->read->timedout || c->write->error || c->write->timedout) { goto invalid; } if (!u->keepalive) { goto invalid; } if (!u->request_body_sent) { goto invalid; } if (ngx_terminate || ngx_exiting) { goto invalid; } if (ngx_handle_read_event(c->read, 0) != NGX_OK) { goto invalid; } ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "free keepalive peer: saving connection %p", c); if (ngx_queue_empty(&kp->conf->free)) { q = ngx_queue_last(&kp->conf->cache); ngx_queue_remove(q); item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue); ngx_http_upstream_keepalive_close(item->connection); } else { q = ngx_queue_head(&kp->conf->free); ngx_queue_remove(q); item = ngx_queue_data(q, ngx_http_upstream_keepalive_cache_t, queue); } ngx_queue_insert_head(&kp->conf->cache, q); item->connection = c; pc->connection = NULL; if (c->read->timer_set) { c->read->delayed = 0; ngx_del_timer(c->read); } if (c->write->timer_set) { ngx_del_timer(c->write); } c->write->handler = ngx_http_upstream_keepalive_dummy_handler; c->read->handler = ngx_http_upstream_keepalive_close_handler; c->data = item; c->idle = 1; c->log = ngx_cycle->log; c->read->log = ngx_cycle->log; c->write->log = ngx_cycle->log; c->pool->log = ngx_cycle->log; item->socklen = pc->socklen; ngx_memcpy(&item->sockaddr, pc->sockaddr, pc->socklen); if (c->read->ready) { ngx_http_upstream_keepalive_close_handler(c->read); } invalid: kp->original_free_peer(pc, kp->data, state); } static void ngx_http_upstream_keepalive_dummy_handler(ngx_event_t *ev) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, ev->log, 0, "keepalive dummy handler"); } static void ngx_http_upstream_keepalive_close_handler(ngx_event_t *ev) { ngx_http_upstream_keepalive_srv_conf_t *conf; ngx_http_upstream_keepalive_cache_t *item; int n; char buf[1]; ngx_connection_t *c; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, ev->log, 0, "keepalive close handler"); c = ev->data; if (c->close) { goto close; } n = recv(c->fd, buf, 1, MSG_PEEK); if (n == -1 && ngx_socket_errno == NGX_EAGAIN) { ev->ready = 0; if (ngx_handle_read_event(c->read, 0) != NGX_OK) { goto close; } return; } close: item = c->data; conf = item->conf; ngx_http_upstream_keepalive_close(c); ngx_queue_remove(&item->queue); ngx_queue_insert_head(&conf->free, &item->queue); } static void ngx_http_upstream_keepalive_close(ngx_connection_t *c) { #if (NGX_HTTP_SSL) if (c->ssl) { c->ssl->no_wait_shutdown = 1; c->ssl->no_send_shutdown = 1; if (ngx_ssl_shutdown(c) == NGX_AGAIN) { c->ssl->handler = ngx_http_upstream_keepalive_close; return; } } #endif ngx_destroy_pool(c->pool); ngx_close_connection(c); } #if (NGX_HTTP_SSL) static ngx_int_t ngx_http_upstream_keepalive_set_session(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_keepalive_peer_data_t *kp = data; return kp->original_set_session(pc, kp->data); } static void ngx_http_upstream_keepalive_save_session(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_keepalive_peer_data_t *kp = data; kp->original_save_session(pc, kp->data); return; } #endif static void * ngx_http_upstream_keepalive_create_conf(ngx_conf_t *cf) { ngx_http_upstream_keepalive_srv_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_keepalive_srv_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->original_init_upstream = NULL; * conf->original_init_peer = NULL; * conf->max_cached = 0; */ return conf; } static char * ngx_http_upstream_keepalive(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_upstream_srv_conf_t *uscf; ngx_http_upstream_keepalive_srv_conf_t *kcf = conf; ngx_int_t n; ngx_str_t *value; if (kcf->max_cached) { return "is duplicate"; } /* read options */ value = cf->args->elts; n = ngx_atoi(value[1].data, value[1].len); if (n == NGX_ERROR || n == 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid value \"%V\" in \"%V\" directive", &value[1], &cmd->name); return NGX_CONF_ERROR; } kcf->max_cached = n; uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module); kcf->original_init_upstream = uscf->peer.init_upstream ? uscf->peer.init_upstream : ngx_http_upstream_init_round_robin; uscf->peer.init_upstream = ngx_http_upstream_init_keepalive; return NGX_CONF_OK; }