Mercurial > hg > nginx-quic
view src/core/ngx_regex.c @ 4664:356c91151658 stable-1.2
Merge of r4618: rewrite escaping fix (ticket #162).
The following code resulted in incorrect escaping of uri and possible
segfault:
location / {
rewrite ^(.*) $1?c=$1;
return 200 "$uri";
}
If there were arguments in a rewrite's replacement string, and length was
actually calculated (due to duplicate captures as in the example above,
or variables present), the is_args flag was set and incorrectly copied
after length calculation. This resulted in escaping applied to the uri part
of the replacement, resulting in incorrect escaping. Additionally, buffer
was allocated without escaping expected, thus this also resulted in buffer
overrun and possible segfault.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 04 Jun 2012 11:07:19 +0000 |
parents | 196c3dacff0d |
children | 6e1a48bcf915 |
line wrap: on
line source
/* * 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_TAKE1, 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) { #if (NGX_THREADS) ngx_core_tls_t *tls; if (ngx_threaded) { tls = ngx_thread_get_tls(ngx_core_tls_key); tls->pool = pool; return; } #endif ngx_pcre_pool = pool; } static ngx_inline void ngx_regex_malloc_done(void) { #if (NGX_THREADS) ngx_core_tls_t *tls; if (ngx_threaded) { tls = ngx_thread_get_tls(ngx_core_tls_key); tls->pool = NULL; return; } #endif 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) { return NGX_ERROR; } rc->regex->pcre = re; /* do not study at runtime */ if (ngx_pcre_studies != NULL) { elt = ngx_list_push(ngx_pcre_studies); if (elt == NULL) { return NGX_ERROR; } 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_OK; } 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; #if (NGX_THREADS) ngx_core_tls_t *tls; if (ngx_threaded) { tls = ngx_thread_get_tls(ngx_core_tls_key); pool = tls->pool; } else { pool = ngx_pcre_pool; } #else pool = ngx_pcre_pool; #endif 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->pcre, 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->pcre, 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; }