Mercurial > hg > nginx
view src/http/modules/ngx_http_stub_status_module.c @ 7507:ea05113adbdb
Range filter: fixed loss of incoming chain links.
Filters are not allowed to change incoming chain links, and should allocate
their own links if any modifications are needed. Nevertheless
ngx_http_range_singlepart_body() modified incoming chain links in some
cases, notably at the end of the requested range.
No problems caused by this are currently known, mostly because of
limited number of possible modifications and the position of the range
body filter in the filter chain. Though this behaviour is clearly incorrect
and tests demonstrate that it can at least cause some proxy buffers being
lost when using proxy_force_ranges, leading to less effective handling
of responses.
Fix is to always allocate new chain links in ngx_http_range_singlepart_body().
Links are explicitly freed to ensure constant memory usage with long-lived
requests.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 13 May 2019 22:44:02 +0300 |
parents | 2a288909abc6 |
children | 43a0a9e988be |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> static ngx_int_t ngx_http_stub_status_handler(ngx_http_request_t *r); static ngx_int_t ngx_http_stub_status_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_http_stub_status_add_variables(ngx_conf_t *cf); static char *ngx_http_set_stub_status(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_http_status_commands[] = { { ngx_string("stub_status"), NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_NOARGS|NGX_CONF_TAKE1, ngx_http_set_stub_status, 0, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_stub_status_module_ctx = { ngx_http_stub_status_add_variables, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_stub_status_module = { NGX_MODULE_V1, &ngx_http_stub_status_module_ctx, /* module context */ ngx_http_status_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_http_variable_t ngx_http_stub_status_vars[] = { { ngx_string("connections_active"), NULL, ngx_http_stub_status_variable, 0, NGX_HTTP_VAR_NOCACHEABLE, 0 }, { ngx_string("connections_reading"), NULL, ngx_http_stub_status_variable, 1, NGX_HTTP_VAR_NOCACHEABLE, 0 }, { ngx_string("connections_writing"), NULL, ngx_http_stub_status_variable, 2, NGX_HTTP_VAR_NOCACHEABLE, 0 }, { ngx_string("connections_waiting"), NULL, ngx_http_stub_status_variable, 3, NGX_HTTP_VAR_NOCACHEABLE, 0 }, ngx_http_null_variable }; static ngx_int_t ngx_http_stub_status_handler(ngx_http_request_t *r) { size_t size; ngx_int_t rc; ngx_buf_t *b; ngx_chain_t out; ngx_atomic_int_t ap, hn, ac, rq, rd, wr, wa; if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) { return NGX_HTTP_NOT_ALLOWED; } rc = ngx_http_discard_request_body(r); if (rc != NGX_OK) { return rc; } r->headers_out.content_type_len = sizeof("text/plain") - 1; ngx_str_set(&r->headers_out.content_type, "text/plain"); r->headers_out.content_type_lowcase = NULL; if (r->method == NGX_HTTP_HEAD) { r->headers_out.status = NGX_HTTP_OK; rc = ngx_http_send_header(r); if (rc == NGX_ERROR || rc > NGX_OK || r->header_only) { return rc; } } size = sizeof("Active connections: \n") + NGX_ATOMIC_T_LEN + sizeof("server accepts handled requests\n") - 1 + 6 + 3 * NGX_ATOMIC_T_LEN + sizeof("Reading: Writing: Waiting: \n") + 3 * NGX_ATOMIC_T_LEN; b = ngx_create_temp_buf(r->pool, size); if (b == NULL) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } out.buf = b; out.next = NULL; ap = *ngx_stat_accepted; hn = *ngx_stat_handled; ac = *ngx_stat_active; rq = *ngx_stat_requests; rd = *ngx_stat_reading; wr = *ngx_stat_writing; wa = *ngx_stat_waiting; b->last = ngx_sprintf(b->last, "Active connections: %uA \n", ac); b->last = ngx_cpymem(b->last, "server accepts handled requests\n", sizeof("server accepts handled requests\n") - 1); b->last = ngx_sprintf(b->last, " %uA %uA %uA \n", ap, hn, rq); b->last = ngx_sprintf(b->last, "Reading: %uA Writing: %uA Waiting: %uA \n", rd, wr, wa); r->headers_out.status = NGX_HTTP_OK; r->headers_out.content_length_n = b->last - b->pos; b->last_buf = (r == r->main) ? 1 : 0; b->last_in_chain = 1; rc = ngx_http_send_header(r); if (rc == NGX_ERROR || rc > NGX_OK || r->header_only) { return rc; } return ngx_http_output_filter(r, &out); } static ngx_int_t ngx_http_stub_status_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data) { u_char *p; ngx_atomic_int_t value; p = ngx_pnalloc(r->pool, NGX_ATOMIC_T_LEN); if (p == NULL) { return NGX_ERROR; } switch (data) { case 0: value = *ngx_stat_active; break; case 1: value = *ngx_stat_reading; break; case 2: value = *ngx_stat_writing; break; case 3: value = *ngx_stat_waiting; break; /* suppress warning */ default: value = 0; break; } v->len = ngx_sprintf(p, "%uA", value) - p; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; v->data = p; return NGX_OK; } static ngx_int_t ngx_http_stub_status_add_variables(ngx_conf_t *cf) { ngx_http_variable_t *var, *v; for (v = ngx_http_stub_status_vars; v->name.len; v++) { var = ngx_http_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 char * ngx_http_set_stub_status(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_core_loc_conf_t *clcf; clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module); clcf->handler = ngx_http_stub_status_handler; return NGX_CONF_OK; }