Mercurial > hg > nginx
view src/stream/ngx_stream_upstream.c @ 7098:7bfbf73db920
Stream: relaxed next upstream condition (ticket #1317).
When switching to a next upstream, some buffers could be stuck in the middle
of the filter chain. A condition existed that raised an error when this
happened. As it turned out, this condition prevented switching to a next
upstream if ssl preread was used with the TCP protocol (see the ticket).
In fact, the condition does not make sense for TCP, since after successful
connection to an upstream switching to another upstream never happens. As for
UDP, the issue with stuck buffers is unlikely to happen, but is still possible.
Specifically, if a filter delays sending data to upstream.
The condition can be relaxed to only check the "buffered" bitmask of the
upstream connection. The new condition is simpler and fixes the ticket issue
as well. Additionally, the upstream_out chain is now reset for UDP prior to
connecting to a new upstream to prevent repeating the client data twice.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 11 Sep 2017 15:32:31 +0300 |
parents | 2a288909abc6 |
children | 860d3907da1c |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> static ngx_int_t ngx_stream_upstream_add_variables(ngx_conf_t *cf); static ngx_int_t ngx_stream_upstream_addr_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_stream_upstream_response_time_variable( ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_stream_upstream_bytes_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); static char *ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *dummy); static char *ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static void *ngx_stream_upstream_create_main_conf(ngx_conf_t *cf); static char *ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf); static ngx_command_t ngx_stream_upstream_commands[] = { { ngx_string("upstream"), NGX_STREAM_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE1, ngx_stream_upstream, 0, 0, NULL }, { ngx_string("server"), NGX_STREAM_UPS_CONF|NGX_CONF_1MORE, ngx_stream_upstream_server, NGX_STREAM_SRV_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_upstream_module_ctx = { ngx_stream_upstream_add_variables, /* preconfiguration */ NULL, /* postconfiguration */ ngx_stream_upstream_create_main_conf, /* create main configuration */ ngx_stream_upstream_init_main_conf, /* init main configuration */ NULL, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_upstream_module = { NGX_MODULE_V1, &ngx_stream_upstream_module_ctx, /* module context */ ngx_stream_upstream_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 ngx_stream_variable_t ngx_stream_upstream_vars[] = { { ngx_string("upstream_addr"), NULL, ngx_stream_upstream_addr_variable, 0, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_bytes_sent"), NULL, ngx_stream_upstream_bytes_variable, 0, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_connect_time"), NULL, ngx_stream_upstream_response_time_variable, 2, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_first_byte_time"), NULL, ngx_stream_upstream_response_time_variable, 1, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_session_time"), NULL, ngx_stream_upstream_response_time_variable, 0, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_bytes_received"), NULL, ngx_stream_upstream_bytes_variable, 1, NGX_STREAM_VAR_NOCACHEABLE, 0 }, ngx_stream_null_variable }; static ngx_int_t ngx_stream_upstream_add_variables(ngx_conf_t *cf) { ngx_stream_variable_t *var, *v; for (v = ngx_stream_upstream_vars; v->name.len; v++) { var = ngx_stream_add_variable(cf, &v->name, v->flags); if (var == NULL) { return NGX_ERROR; } var->get_handler = v->get_handler; var->data = v->data; } return NGX_OK; } static ngx_int_t ngx_stream_upstream_addr_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data) { u_char *p; size_t len; ngx_uint_t i; ngx_stream_upstream_state_t *state; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; if (s->upstream_states == NULL || s->upstream_states->nelts == 0) { v->not_found = 1; return NGX_OK; } len = 0; state = s->upstream_states->elts; for (i = 0; i < s->upstream_states->nelts; i++) { if (state[i].peer) { len += state[i].peer->len; } len += 2; } p = ngx_pnalloc(s->connection->pool, len); if (p == NULL) { return NGX_ERROR; } v->data = p; i = 0; for ( ;; ) { if (state[i].peer) { p = ngx_cpymem(p, state[i].peer->data, state[i].peer->len); } if (++i == s->upstream_states->nelts) { break; } *p++ = ','; *p++ = ' '; } v->len = p - v->data; return NGX_OK; } static ngx_int_t ngx_stream_upstream_bytes_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data) { u_char *p; size_t len; ngx_uint_t i; ngx_stream_upstream_state_t *state; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; if (s->upstream_states == NULL || s->upstream_states->nelts == 0) { v->not_found = 1; return NGX_OK; } len = s->upstream_states->nelts * (NGX_OFF_T_LEN + 2); p = ngx_pnalloc(s->connection->pool, len); if (p == NULL) { return NGX_ERROR; } v->data = p; i = 0; state = s->upstream_states->elts; for ( ;; ) { if (data == 1) { p = ngx_sprintf(p, "%O", state[i].bytes_received); } else { p = ngx_sprintf(p, "%O", state[i].bytes_sent); } if (++i == s->upstream_states->nelts) { break; } *p++ = ','; *p++ = ' '; } v->len = p - v->data; return NGX_OK; } static ngx_int_t ngx_stream_upstream_response_time_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data) { u_char *p; size_t len; ngx_uint_t i; ngx_msec_int_t ms; ngx_stream_upstream_state_t *state; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; if (s->upstream_states == NULL || s->upstream_states->nelts == 0) { v->not_found = 1; return NGX_OK; } len = s->upstream_states->nelts * (NGX_TIME_T_LEN + 4 + 2); p = ngx_pnalloc(s->connection->pool, len); if (p == NULL) { return NGX_ERROR; } v->data = p; i = 0; state = s->upstream_states->elts; for ( ;; ) { if (data == 1) { if (state[i].first_byte_time == (ngx_msec_t) -1) { *p++ = '-'; goto next; } ms = state[i].first_byte_time; } else if (data == 2 && state[i].connect_time != (ngx_msec_t) -1) { ms = state[i].connect_time; } else { ms = state[i].response_time; } ms = ngx_max(ms, 0); p = ngx_sprintf(p, "%T.%03M", (time_t) ms / 1000, ms % 1000); next: if (++i == s->upstream_states->nelts) { break; } *p++ = ','; *p++ = ' '; } v->len = p - v->data; return NGX_OK; } static char * ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *dummy) { char *rv; void *mconf; ngx_str_t *value; ngx_url_t u; ngx_uint_t m; ngx_conf_t pcf; ngx_stream_module_t *module; ngx_stream_conf_ctx_t *ctx, *stream_ctx; ngx_stream_upstream_srv_conf_t *uscf; ngx_memzero(&u, sizeof(ngx_url_t)); value = cf->args->elts; u.host = value[1]; u.no_resolve = 1; u.no_port = 1; uscf = ngx_stream_upstream_add(cf, &u, NGX_STREAM_UPSTREAM_CREATE |NGX_STREAM_UPSTREAM_WEIGHT |NGX_STREAM_UPSTREAM_MAX_CONNS |NGX_STREAM_UPSTREAM_MAX_FAILS |NGX_STREAM_UPSTREAM_FAIL_TIMEOUT |NGX_STREAM_UPSTREAM_DOWN |NGX_STREAM_UPSTREAM_BACKUP); if (uscf == NULL) { return NGX_CONF_ERROR; } ctx = ngx_pcalloc(cf->pool, sizeof(ngx_stream_conf_ctx_t)); if (ctx == NULL) { return NGX_CONF_ERROR; } stream_ctx = cf->ctx; ctx->main_conf = stream_ctx->main_conf; /* the upstream{}'s srv_conf */ ctx->srv_conf = ngx_pcalloc(cf->pool, sizeof(void *) * ngx_stream_max_module); if (ctx->srv_conf == NULL) { return NGX_CONF_ERROR; } ctx->srv_conf[ngx_stream_upstream_module.ctx_index] = uscf; uscf->srv_conf = ctx->srv_conf; for (m = 0; cf->cycle->modules[m]; m++) { if (cf->cycle->modules[m]->type != NGX_STREAM_MODULE) { continue; } module = cf->cycle->modules[m]->ctx; if (module->create_srv_conf) { mconf = module->create_srv_conf(cf); if (mconf == NULL) { return NGX_CONF_ERROR; } ctx->srv_conf[cf->cycle->modules[m]->ctx_index] = mconf; } } uscf->servers = ngx_array_create(cf->pool, 4, sizeof(ngx_stream_upstream_server_t)); if (uscf->servers == NULL) { return NGX_CONF_ERROR; } /* parse inside upstream{} */ pcf = *cf; cf->ctx = ctx; cf->cmd_type = NGX_STREAM_UPS_CONF; rv = ngx_conf_parse(cf, NULL); *cf = pcf; if (rv != NGX_CONF_OK) { return rv; } if (uscf->servers->nelts == 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "no servers are inside upstream"); return NGX_CONF_ERROR; } return rv; } static char * ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_stream_upstream_srv_conf_t *uscf = conf; time_t fail_timeout; ngx_str_t *value, s; ngx_url_t u; ngx_int_t weight, max_conns, max_fails; ngx_uint_t i; ngx_stream_upstream_server_t *us; us = ngx_array_push(uscf->servers); if (us == NULL) { return NGX_CONF_ERROR; } ngx_memzero(us, sizeof(ngx_stream_upstream_server_t)); value = cf->args->elts; weight = 1; max_conns = 0; max_fails = 1; fail_timeout = 10; for (i = 2; i < cf->args->nelts; i++) { if (ngx_strncmp(value[i].data, "weight=", 7) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_WEIGHT)) { goto not_supported; } weight = ngx_atoi(&value[i].data[7], value[i].len - 7); if (weight == NGX_ERROR || weight == 0) { goto invalid; } continue; } if (ngx_strncmp(value[i].data, "max_conns=", 10) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_MAX_CONNS)) { goto not_supported; } max_conns = ngx_atoi(&value[i].data[10], value[i].len - 10); if (max_conns == NGX_ERROR) { goto invalid; } continue; } if (ngx_strncmp(value[i].data, "max_fails=", 10) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_MAX_FAILS)) { goto not_supported; } max_fails = ngx_atoi(&value[i].data[10], value[i].len - 10); if (max_fails == NGX_ERROR) { goto invalid; } continue; } if (ngx_strncmp(value[i].data, "fail_timeout=", 13) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_FAIL_TIMEOUT)) { goto not_supported; } s.len = value[i].len - 13; s.data = &value[i].data[13]; fail_timeout = ngx_parse_time(&s, 1); if (fail_timeout == (time_t) NGX_ERROR) { goto invalid; } continue; } if (ngx_strcmp(value[i].data, "backup") == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_BACKUP)) { goto not_supported; } us->backup = 1; continue; } if (ngx_strcmp(value[i].data, "down") == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_DOWN)) { goto not_supported; } us->down = 1; continue; } goto invalid; } ngx_memzero(&u, sizeof(ngx_url_t)); u.url = value[1]; if (ngx_parse_url(cf->pool, &u) != NGX_OK) { if (u.err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in upstream \"%V\"", u.err, &u.url); } return NGX_CONF_ERROR; } if (u.no_port) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "no port in upstream \"%V\"", &u.url); return NGX_CONF_ERROR; } us->name = u.url; us->addrs = u.addrs; us->naddrs = u.naddrs; us->weight = weight; us->max_conns = max_conns; us->max_fails = max_fails; us->fail_timeout = fail_timeout; return NGX_CONF_OK; invalid: ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"", &value[i]); return NGX_CONF_ERROR; not_supported: ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "balancing method does not support parameter \"%V\"", &value[i]); return NGX_CONF_ERROR; } ngx_stream_upstream_srv_conf_t * ngx_stream_upstream_add(ngx_conf_t *cf, ngx_url_t *u, ngx_uint_t flags) { ngx_uint_t i; ngx_stream_upstream_server_t *us; ngx_stream_upstream_srv_conf_t *uscf, **uscfp; ngx_stream_upstream_main_conf_t *umcf; if (!(flags & NGX_STREAM_UPSTREAM_CREATE)) { if (ngx_parse_url(cf->pool, u) != NGX_OK) { if (u->err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in upstream \"%V\"", u->err, &u->url); } return NULL; } } umcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_upstream_module); uscfp = umcf->upstreams.elts; for (i = 0; i < umcf->upstreams.nelts; i++) { if (uscfp[i]->host.len != u->host.len || ngx_strncasecmp(uscfp[i]->host.data, u->host.data, u->host.len) != 0) { continue; } if ((flags & NGX_STREAM_UPSTREAM_CREATE) && (uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE)) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate upstream \"%V\"", &u->host); return NULL; } if ((uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE) && !u->no_port) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "upstream \"%V\" may not have port %d", &u->host, u->port); return NULL; } if ((flags & NGX_STREAM_UPSTREAM_CREATE) && !uscfp[i]->no_port) { ngx_log_error(NGX_LOG_EMERG, cf->log, 0, "upstream \"%V\" may not have port %d in %s:%ui", &u->host, uscfp[i]->port, uscfp[i]->file_name, uscfp[i]->line); return NULL; } if (uscfp[i]->port != u->port) { continue; } if (flags & NGX_STREAM_UPSTREAM_CREATE) { uscfp[i]->flags = flags; } return uscfp[i]; } uscf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_srv_conf_t)); if (uscf == NULL) { return NULL; } uscf->flags = flags; uscf->host = u->host; uscf->file_name = cf->conf_file->file.name.data; uscf->line = cf->conf_file->line; uscf->port = u->port; uscf->no_port = u->no_port; if (u->naddrs == 1 && (u->port || u->family == AF_UNIX)) { uscf->servers = ngx_array_create(cf->pool, 1, sizeof(ngx_stream_upstream_server_t)); if (uscf->servers == NULL) { return NULL; } us = ngx_array_push(uscf->servers); if (us == NULL) { return NULL; } ngx_memzero(us, sizeof(ngx_stream_upstream_server_t)); us->addrs = u->addrs; us->naddrs = 1; } uscfp = ngx_array_push(&umcf->upstreams); if (uscfp == NULL) { return NULL; } *uscfp = uscf; return uscf; } static void * ngx_stream_upstream_create_main_conf(ngx_conf_t *cf) { ngx_stream_upstream_main_conf_t *umcf; umcf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_main_conf_t)); if (umcf == NULL) { return NULL; } if (ngx_array_init(&umcf->upstreams, cf->pool, 4, sizeof(ngx_stream_upstream_srv_conf_t *)) != NGX_OK) { return NULL; } return umcf; } static char * ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf) { ngx_stream_upstream_main_conf_t *umcf = conf; ngx_uint_t i; ngx_stream_upstream_init_pt init; ngx_stream_upstream_srv_conf_t **uscfp; uscfp = umcf->upstreams.elts; for (i = 0; i < umcf->upstreams.nelts; i++) { init = uscfp[i]->peer.init_upstream ? uscfp[i]->peer.init_upstream : ngx_stream_upstream_init_round_robin; if (init(cf, uscfp[i]) != NGX_OK) { return NGX_CONF_ERROR; } } return NGX_CONF_OK; }