Mercurial > hg > nginx
view src/core/ngx_regex.c @ 7142:b9d919b53593 stable-1.12
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 | 640288d0e1bc |
children | f684178faec9 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> typedef struct { ngx_flag_t pcre_jit; } ngx_regex_conf_t; static void * ngx_libc_cdecl ngx_regex_malloc(size_t size); static void ngx_libc_cdecl ngx_regex_free(void *p); #if (NGX_HAVE_PCRE_JIT) static void ngx_pcre_free_studies(void *data); #endif static ngx_int_t ngx_regex_module_init(ngx_cycle_t *cycle); static void *ngx_regex_create_conf(ngx_cycle_t *cycle); static char *ngx_regex_init_conf(ngx_cycle_t *cycle, void *conf); static char *ngx_regex_pcre_jit(ngx_conf_t *cf, void *post, void *data); static ngx_conf_post_t ngx_regex_pcre_jit_post = { ngx_regex_pcre_jit }; static ngx_command_t ngx_regex_commands[] = { { ngx_string("pcre_jit"), NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_FLAG, ngx_conf_set_flag_slot, 0, offsetof(ngx_regex_conf_t, pcre_jit), &ngx_regex_pcre_jit_post }, ngx_null_command }; static ngx_core_module_t ngx_regex_module_ctx = { ngx_string("regex"), ngx_regex_create_conf, ngx_regex_init_conf }; ngx_module_t ngx_regex_module = { NGX_MODULE_V1, &ngx_regex_module_ctx, /* module context */ ngx_regex_commands, /* module directives */ NGX_CORE_MODULE, /* module type */ NULL, /* init master */ ngx_regex_module_init, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_pool_t *ngx_pcre_pool; static ngx_list_t *ngx_pcre_studies; void ngx_regex_init(void) { pcre_malloc = ngx_regex_malloc; pcre_free = ngx_regex_free; } static ngx_inline void ngx_regex_malloc_init(ngx_pool_t *pool) { ngx_pcre_pool = pool; } static ngx_inline void ngx_regex_malloc_done(void) { ngx_pcre_pool = NULL; } ngx_int_t ngx_regex_compile(ngx_regex_compile_t *rc) { int n, erroff; char *p; pcre *re; const char *errstr; ngx_regex_elt_t *elt; ngx_regex_malloc_init(rc->pool); re = pcre_compile((const char *) rc->pattern.data, (int) rc->options, &errstr, &erroff, NULL); /* ensure that there is no current pool */ ngx_regex_malloc_done(); if (re == NULL) { if ((size_t) erroff == rc->pattern.len) { rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, "pcre_compile() failed: %s in \"%V\"", errstr, &rc->pattern) - rc->err.data; } else { rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, "pcre_compile() failed: %s in \"%V\" at \"%s\"", errstr, &rc->pattern, rc->pattern.data + erroff) - rc->err.data; } return NGX_ERROR; } rc->regex = ngx_pcalloc(rc->pool, sizeof(ngx_regex_t)); if (rc->regex == NULL) { goto nomem; } rc->regex->code = re; /* do not study at runtime */ if (ngx_pcre_studies != NULL) { elt = ngx_list_push(ngx_pcre_studies); if (elt == NULL) { goto nomem; } elt->regex = rc->regex; elt->name = rc->pattern.data; } n = pcre_fullinfo(re, NULL, PCRE_INFO_CAPTURECOUNT, &rc->captures); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_CAPTURECOUNT) failed: %d"; goto failed; } if (rc->captures == 0) { return NGX_OK; } n = pcre_fullinfo(re, NULL, PCRE_INFO_NAMECOUNT, &rc->named_captures); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_NAMECOUNT) failed: %d"; goto failed; } if (rc->named_captures == 0) { return NGX_OK; } n = pcre_fullinfo(re, NULL, PCRE_INFO_NAMEENTRYSIZE, &rc->name_size); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_NAMEENTRYSIZE) failed: %d"; goto failed; } n = pcre_fullinfo(re, NULL, PCRE_INFO_NAMETABLE, &rc->names); if (n < 0) { p = "pcre_fullinfo(\"%V\", PCRE_INFO_NAMETABLE) failed: %d"; goto failed; } return NGX_OK; failed: rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, p, &rc->pattern, n) - rc->err.data; return NGX_ERROR; nomem: rc->err.len = ngx_snprintf(rc->err.data, rc->err.len, "regex \"%V\" compilation failed: no memory", &rc->pattern) - rc->err.data; return NGX_ERROR; } ngx_int_t ngx_regex_exec_array(ngx_array_t *a, ngx_str_t *s, ngx_log_t *log) { ngx_int_t n; ngx_uint_t i; ngx_regex_elt_t *re; re = a->elts; for (i = 0; i < a->nelts; i++) { n = ngx_regex_exec(re[i].regex, s, NULL, 0); if (n == NGX_REGEX_NO_MATCHED) { continue; } if (n < 0) { ngx_log_error(NGX_LOG_ALERT, log, 0, ngx_regex_exec_n " failed: %i on \"%V\" using \"%s\"", n, s, re[i].name); return NGX_ERROR; } /* match */ return NGX_OK; } return NGX_DECLINED; } static void * ngx_libc_cdecl ngx_regex_malloc(size_t size) { ngx_pool_t *pool; pool = ngx_pcre_pool; if (pool) { return ngx_palloc(pool, size); } return NULL; } static void ngx_libc_cdecl ngx_regex_free(void *p) { return; } #if (NGX_HAVE_PCRE_JIT) static void ngx_pcre_free_studies(void *data) { ngx_list_t *studies = data; ngx_uint_t i; ngx_list_part_t *part; ngx_regex_elt_t *elts; part = &studies->part; elts = part->elts; for (i = 0 ; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; elts = part->elts; i = 0; } if (elts[i].regex->extra != NULL) { pcre_free_study(elts[i].regex->extra); } } } #endif static ngx_int_t ngx_regex_module_init(ngx_cycle_t *cycle) { int opt; const char *errstr; ngx_uint_t i; ngx_list_part_t *part; ngx_regex_elt_t *elts; opt = 0; #if (NGX_HAVE_PCRE_JIT) { ngx_regex_conf_t *rcf; ngx_pool_cleanup_t *cln; rcf = (ngx_regex_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_regex_module); if (rcf->pcre_jit) { opt = PCRE_STUDY_JIT_COMPILE; /* * The PCRE JIT compiler uses mmap for its executable codes, so we * have to explicitly call the pcre_free_study() function to free * this memory. */ cln = ngx_pool_cleanup_add(cycle->pool, 0); if (cln == NULL) { return NGX_ERROR; } cln->handler = ngx_pcre_free_studies; cln->data = ngx_pcre_studies; } } #endif ngx_regex_malloc_init(cycle->pool); part = &ngx_pcre_studies->part; elts = part->elts; for (i = 0 ; /* void */ ; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; elts = part->elts; i = 0; } elts[i].regex->extra = pcre_study(elts[i].regex->code, opt, &errstr); if (errstr != NULL) { ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "pcre_study() failed: %s in \"%s\"", errstr, elts[i].name); } #if (NGX_HAVE_PCRE_JIT) if (opt & PCRE_STUDY_JIT_COMPILE) { int jit, n; jit = 0; n = pcre_fullinfo(elts[i].regex->code, elts[i].regex->extra, PCRE_INFO_JIT, &jit); if (n != 0 || jit != 1) { ngx_log_error(NGX_LOG_INFO, cycle->log, 0, "JIT compiler does not support pattern: \"%s\"", elts[i].name); } } #endif } ngx_regex_malloc_done(); ngx_pcre_studies = NULL; return NGX_OK; } static void * ngx_regex_create_conf(ngx_cycle_t *cycle) { ngx_regex_conf_t *rcf; rcf = ngx_pcalloc(cycle->pool, sizeof(ngx_regex_conf_t)); if (rcf == NULL) { return NULL; } rcf->pcre_jit = NGX_CONF_UNSET; ngx_pcre_studies = ngx_list_create(cycle->pool, 8, sizeof(ngx_regex_elt_t)); if (ngx_pcre_studies == NULL) { return NULL; } return rcf; } static char * ngx_regex_init_conf(ngx_cycle_t *cycle, void *conf) { ngx_regex_conf_t *rcf = conf; ngx_conf_init_value(rcf->pcre_jit, 0); return NGX_CONF_OK; } static char * ngx_regex_pcre_jit(ngx_conf_t *cf, void *post, void *data) { ngx_flag_t *fp = data; if (*fp == 0) { return NGX_CONF_OK; } #if (NGX_HAVE_PCRE_JIT) { int jit, r; jit = 0; r = pcre_config(PCRE_CONFIG_JIT, &jit); if (r != 0 || jit != 1) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "PCRE library does not support JIT"); *fp = 0; } } #else ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "nginx was built without PCRE JIT support"); *fp = 0; #endif return NGX_CONF_OK; }