Mercurial > hg > nginx
view src/http/modules/ngx_http_referer_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 | 7564a919d333 |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #define NGX_HTTP_REFERER_NO_URI_PART ((void *) 4) typedef struct { ngx_hash_combined_t hash; #if (NGX_PCRE) ngx_array_t *regex; ngx_array_t *server_name_regex; #endif ngx_flag_t no_referer; ngx_flag_t blocked_referer; ngx_flag_t server_names; ngx_hash_keys_arrays_t *keys; ngx_uint_t referer_hash_max_size; ngx_uint_t referer_hash_bucket_size; } ngx_http_referer_conf_t; static ngx_int_t ngx_http_referer_add_variables(ngx_conf_t *cf); static void * ngx_http_referer_create_conf(ngx_conf_t *cf); static char * ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent, void *child); static char *ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_int_t ngx_http_add_referer(ngx_conf_t *cf, ngx_hash_keys_arrays_t *keys, ngx_str_t *value, ngx_str_t *uri); static ngx_int_t ngx_http_add_regex_referer(ngx_conf_t *cf, ngx_http_referer_conf_t *rlcf, ngx_str_t *name); #if (NGX_PCRE) static ngx_int_t ngx_http_add_regex_server_name(ngx_conf_t *cf, ngx_http_referer_conf_t *rlcf, ngx_http_regex_t *regex); #endif static int ngx_libc_cdecl ngx_http_cmp_referer_wildcards(const void *one, const void *two); static ngx_command_t ngx_http_referer_commands[] = { { ngx_string("valid_referers"), NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE, ngx_http_valid_referers, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, { ngx_string("referer_hash_max_size"), NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_referer_conf_t, referer_hash_max_size), NULL }, { ngx_string("referer_hash_bucket_size"), NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_referer_conf_t, referer_hash_bucket_size), NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_referer_module_ctx = { ngx_http_referer_add_variables, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_referer_create_conf, /* create location configuration */ ngx_http_referer_merge_conf /* merge location configuration */ }; ngx_module_t ngx_http_referer_module = { NGX_MODULE_V1, &ngx_http_referer_module_ctx, /* module context */ ngx_http_referer_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_str_t ngx_http_invalid_referer_name = ngx_string("invalid_referer"); static ngx_int_t ngx_http_referer_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data) { u_char *p, *ref, *last; size_t len; ngx_str_t *uri; ngx_uint_t i, key; ngx_http_referer_conf_t *rlcf; u_char buf[256]; #if (NGX_PCRE) ngx_int_t rc; ngx_str_t referer; #endif rlcf = ngx_http_get_module_loc_conf(r, ngx_http_referer_module); if (rlcf->hash.hash.buckets == NULL && rlcf->hash.wc_head == NULL && rlcf->hash.wc_tail == NULL #if (NGX_PCRE) && rlcf->regex == NULL && rlcf->server_name_regex == NULL #endif ) { goto valid; } if (r->headers_in.referer == NULL) { if (rlcf->no_referer) { goto valid; } goto invalid; } len = r->headers_in.referer->value.len; ref = r->headers_in.referer->value.data; if (len >= sizeof("http://i.ru") - 1) { last = ref + len; if (ngx_strncasecmp(ref, (u_char *) "http://", 7) == 0) { ref += 7; len -= 7; goto valid_scheme; } else if (ngx_strncasecmp(ref, (u_char *) "https://", 8) == 0) { ref += 8; len -= 8; goto valid_scheme; } } if (rlcf->blocked_referer) { goto valid; } goto invalid; valid_scheme: i = 0; key = 0; for (p = ref; p < last; p++) { if (*p == '/' || *p == ':') { break; } if (i == 256) { goto invalid; } buf[i] = ngx_tolower(*p); key = ngx_hash(key, buf[i++]); } uri = ngx_hash_find_combined(&rlcf->hash, key, buf, p - ref); if (uri) { goto uri; } #if (NGX_PCRE) if (rlcf->server_name_regex) { referer.len = p - ref; referer.data = buf; rc = ngx_regex_exec_array(rlcf->server_name_regex, &referer, r->connection->log); if (rc == NGX_OK) { goto valid; } if (rc == NGX_ERROR) { return rc; } /* NGX_DECLINED */ } if (rlcf->regex) { referer.len = len; referer.data = ref; rc = ngx_regex_exec_array(rlcf->regex, &referer, r->connection->log); if (rc == NGX_OK) { goto valid; } if (rc == NGX_ERROR) { return rc; } /* NGX_DECLINED */ } #endif invalid: *v = ngx_http_variable_true_value; return NGX_OK; uri: for ( /* void */ ; p < last; p++) { if (*p == '/') { break; } } len = last - p; if (uri == NGX_HTTP_REFERER_NO_URI_PART) { goto valid; } if (len < uri->len || ngx_strncmp(uri->data, p, uri->len) != 0) { goto invalid; } valid: *v = ngx_http_variable_null_value; return NGX_OK; } static ngx_int_t ngx_http_referer_add_variables(ngx_conf_t *cf) { ngx_http_variable_t *var; var = ngx_http_add_variable(cf, &ngx_http_invalid_referer_name, NGX_HTTP_VAR_CHANGEABLE); if (var == NULL) { return NGX_ERROR; } var->get_handler = ngx_http_referer_variable; return NGX_OK; } static void * ngx_http_referer_create_conf(ngx_conf_t *cf) { ngx_http_referer_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_referer_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->hash = { NULL }; * conf->server_names = 0; * conf->keys = NULL; */ #if (NGX_PCRE) conf->regex = NGX_CONF_UNSET_PTR; conf->server_name_regex = NGX_CONF_UNSET_PTR; #endif conf->no_referer = NGX_CONF_UNSET; conf->blocked_referer = NGX_CONF_UNSET; conf->referer_hash_max_size = NGX_CONF_UNSET_UINT; conf->referer_hash_bucket_size = NGX_CONF_UNSET_UINT; return conf; } static char * ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_referer_conf_t *prev = parent; ngx_http_referer_conf_t *conf = child; ngx_uint_t n; ngx_hash_init_t hash; ngx_http_server_name_t *sn; ngx_http_core_srv_conf_t *cscf; if (conf->keys == NULL) { conf->hash = prev->hash; #if (NGX_PCRE) ngx_conf_merge_ptr_value(conf->regex, prev->regex, NULL); ngx_conf_merge_ptr_value(conf->server_name_regex, prev->server_name_regex, NULL); #endif ngx_conf_merge_value(conf->no_referer, prev->no_referer, 0); ngx_conf_merge_value(conf->blocked_referer, prev->blocked_referer, 0); ngx_conf_merge_uint_value(conf->referer_hash_max_size, prev->referer_hash_max_size, 2048); ngx_conf_merge_uint_value(conf->referer_hash_bucket_size, prev->referer_hash_bucket_size, 64); return NGX_CONF_OK; } if (conf->server_names == 1) { cscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_core_module); sn = cscf->server_names.elts; for (n = 0; n < cscf->server_names.nelts; n++) { #if (NGX_PCRE) if (sn[n].regex) { if (ngx_http_add_regex_server_name(cf, conf, sn[n].regex) != NGX_OK) { return NGX_CONF_ERROR; } continue; } #endif if (ngx_http_add_referer(cf, conf->keys, &sn[n].name, NULL) != NGX_OK) { return NGX_CONF_ERROR; } } } if ((conf->no_referer == 1 || conf->blocked_referer == 1) && conf->keys->keys.nelts == 0 && conf->keys->dns_wc_head.nelts == 0 && conf->keys->dns_wc_tail.nelts == 0) { ngx_log_error(NGX_LOG_EMERG, cf->log, 0, "the \"none\" or \"blocked\" referers are specified " "in the \"valid_referers\" directive " "without any valid referer"); return NGX_CONF_ERROR; } ngx_conf_merge_uint_value(conf->referer_hash_max_size, prev->referer_hash_max_size, 2048); ngx_conf_merge_uint_value(conf->referer_hash_bucket_size, prev->referer_hash_bucket_size, 64); conf->referer_hash_bucket_size = ngx_align(conf->referer_hash_bucket_size, ngx_cacheline_size); hash.key = ngx_hash_key_lc; hash.max_size = conf->referer_hash_max_size; hash.bucket_size = conf->referer_hash_bucket_size; hash.name = "referer_hash"; hash.pool = cf->pool; if (conf->keys->keys.nelts) { hash.hash = &conf->hash.hash; hash.temp_pool = NULL; if (ngx_hash_init(&hash, conf->keys->keys.elts, conf->keys->keys.nelts) != NGX_OK) { return NGX_CONF_ERROR; } } if (conf->keys->dns_wc_head.nelts) { ngx_qsort(conf->keys->dns_wc_head.elts, (size_t) conf->keys->dns_wc_head.nelts, sizeof(ngx_hash_key_t), ngx_http_cmp_referer_wildcards); hash.hash = NULL; hash.temp_pool = cf->temp_pool; if (ngx_hash_wildcard_init(&hash, conf->keys->dns_wc_head.elts, conf->keys->dns_wc_head.nelts) != NGX_OK) { return NGX_CONF_ERROR; } conf->hash.wc_head = (ngx_hash_wildcard_t *) hash.hash; } if (conf->keys->dns_wc_tail.nelts) { ngx_qsort(conf->keys->dns_wc_tail.elts, (size_t) conf->keys->dns_wc_tail.nelts, sizeof(ngx_hash_key_t), ngx_http_cmp_referer_wildcards); hash.hash = NULL; hash.temp_pool = cf->temp_pool; if (ngx_hash_wildcard_init(&hash, conf->keys->dns_wc_tail.elts, conf->keys->dns_wc_tail.nelts) != NGX_OK) { return NGX_CONF_ERROR; } conf->hash.wc_tail = (ngx_hash_wildcard_t *) hash.hash; } #if (NGX_PCRE) ngx_conf_merge_ptr_value(conf->regex, prev->regex, NULL); ngx_conf_merge_ptr_value(conf->server_name_regex, prev->server_name_regex, NULL); #endif if (conf->no_referer == NGX_CONF_UNSET) { conf->no_referer = 0; } if (conf->blocked_referer == NGX_CONF_UNSET) { conf->blocked_referer = 0; } conf->keys = NULL; return NGX_CONF_OK; } static char * ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_referer_conf_t *rlcf = conf; u_char *p; ngx_str_t *value, uri; ngx_uint_t i; if (rlcf->keys == NULL) { rlcf->keys = ngx_pcalloc(cf->temp_pool, sizeof(ngx_hash_keys_arrays_t)); if (rlcf->keys == NULL) { return NGX_CONF_ERROR; } rlcf->keys->pool = cf->pool; rlcf->keys->temp_pool = cf->pool; if (ngx_hash_keys_array_init(rlcf->keys, NGX_HASH_SMALL) != NGX_OK) { return NGX_CONF_ERROR; } } value = cf->args->elts; for (i = 1; i < cf->args->nelts; i++) { if (value[i].len == 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid referer \"%V\"", &value[i]); return NGX_CONF_ERROR; } if (ngx_strcmp(value[i].data, "none") == 0) { rlcf->no_referer = 1; continue; } if (ngx_strcmp(value[i].data, "blocked") == 0) { rlcf->blocked_referer = 1; continue; } if (ngx_strcmp(value[i].data, "server_names") == 0) { rlcf->server_names = 1; continue; } if (value[i].data[0] == '~') { if (ngx_http_add_regex_referer(cf, rlcf, &value[i]) != NGX_OK) { return NGX_CONF_ERROR; } continue; } ngx_str_null(&uri); p = (u_char *) ngx_strchr(value[i].data, '/'); if (p) { uri.len = (value[i].data + value[i].len) - p; uri.data = p; value[i].len = p - value[i].data; } if (ngx_http_add_referer(cf, rlcf->keys, &value[i], &uri) != NGX_OK) { return NGX_CONF_ERROR; } } return NGX_CONF_OK; } static ngx_int_t ngx_http_add_referer(ngx_conf_t *cf, ngx_hash_keys_arrays_t *keys, ngx_str_t *value, ngx_str_t *uri) { ngx_int_t rc; ngx_str_t *u; if (uri == NULL || uri->len == 0) { u = NGX_HTTP_REFERER_NO_URI_PART; } else { u = ngx_palloc(cf->pool, sizeof(ngx_str_t)); if (u == NULL) { return NGX_ERROR; } *u = *uri; } rc = ngx_hash_add_key(keys, value, u, NGX_HASH_WILDCARD_KEY); if (rc == NGX_OK) { return NGX_OK; } if (rc == NGX_DECLINED) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid hostname or wildcard \"%V\"", value); } if (rc == NGX_BUSY) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "conflicting parameter \"%V\"", value); } return NGX_ERROR; } static ngx_int_t ngx_http_add_regex_referer(ngx_conf_t *cf, ngx_http_referer_conf_t *rlcf, ngx_str_t *name) { #if (NGX_PCRE) ngx_regex_elt_t *re; ngx_regex_compile_t rc; u_char errstr[NGX_MAX_CONF_ERRSTR]; if (name->len == 1) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "empty regex in \"%V\"", name); return NGX_ERROR; } if (rlcf->regex == NGX_CONF_UNSET_PTR) { rlcf->regex = ngx_array_create(cf->pool, 2, sizeof(ngx_regex_elt_t)); if (rlcf->regex == NULL) { return NGX_ERROR; } } re = ngx_array_push(rlcf->regex); if (re == NULL) { return NGX_ERROR; } name->len--; name->data++; ngx_memzero(&rc, sizeof(ngx_regex_compile_t)); rc.pattern = *name; rc.pool = cf->pool; rc.options = NGX_REGEX_CASELESS; rc.err.len = NGX_MAX_CONF_ERRSTR; rc.err.data = errstr; if (ngx_regex_compile(&rc) != NGX_OK) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%V", &rc.err); return NGX_ERROR; } re->regex = rc.regex; re->name = name->data; return NGX_OK; #else ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "the using of the regex \"%V\" requires PCRE library", name); return NGX_ERROR; #endif } #if (NGX_PCRE) static ngx_int_t ngx_http_add_regex_server_name(ngx_conf_t *cf, ngx_http_referer_conf_t *rlcf, ngx_http_regex_t *regex) { ngx_regex_elt_t *re; if (rlcf->server_name_regex == NGX_CONF_UNSET_PTR) { rlcf->server_name_regex = ngx_array_create(cf->pool, 2, sizeof(ngx_regex_elt_t)); if (rlcf->server_name_regex == NULL) { return NGX_ERROR; } } re = ngx_array_push(rlcf->server_name_regex); if (re == NULL) { return NGX_ERROR; } re->regex = regex->regex; re->name = regex->name.data; return NGX_OK; } #endif static int ngx_libc_cdecl ngx_http_cmp_referer_wildcards(const void *one, const void *two) { ngx_hash_key_t *first, *second; first = (ngx_hash_key_t *) one; second = (ngx_hash_key_t *) two; return ngx_dns_strcmp(first->key.data, second->key.data); }