Mercurial > hg > nginx
view src/stream/ngx_stream_upstream.c @ 9300:5be23505292b
SSI: fixed incorrect or duplicate stub output.
Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set
if there are data in the first buffer sent in the subrequest. As a
result, following the change mentioned this flag cannot be used to
prevent duplicate ngx_http_ssi_stub_output() calls, since it is not
set if there was already some output, but the first buffer was empty.
Still, when there are multiple subrequests, even an empty subrequest
response might be delayed by the postpone filter, leading to a second
call of ngx_http_ssi_stub_output() during finalization from
ngx_http_writer() the subreqest buffers are released by the postpone
filter. Since r->request_output is not set after the first call, this
resulted in duplicate stub output.
Additionally, checking only the first buffer might be wrong in some
unusual cases. For example, the first buffer might be empty if
$r->flush() is called before printing any data in the embedded Perl
module.
Depending on the postpone_output value and corresponding sizes, this
issue can result in either duplicate or unexpected stub output, or
"zero size buf in writer" alerts.
Following 8124:f5515e727656 (1.23.4), it became slightly easier to
reproduce the issue, as empty static files and empty cache items now
result in a response with an empty buffer. Before the change, an empty
proxied response can be used to reproduce the issue.
Fix is check all buffers and set r->request_output if any non-empty
buffers are sent. This ensures that all unusual cases of non-empty
responses are covered, and also that r->request_output will be set
after the first stub output, preventing duplicate output.
Reported by Jan Gassen.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 04 Jul 2024 17:41:28 +0300 |
parents | 860d3907da1c |
children |
line wrap: on
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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) { ms = state[i].first_byte_time; } else if (data == 2) { ms = state[i].connect_time; } else { ms = state[i].response_time; } if (ms != -1) { ms = ngx_max(ms, 0); p = ngx_sprintf(p, "%T.%03M", (time_t) ms / 1000, ms % 1000); } else { *p++ = '-'; } 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; }