/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License.
*/
/* * delete all URL entities from the cache *
*/ int cache_remove_url(cache_request_rec *cache, request_rec *r)
{
cache_provider_list *list;
cache_handle_t *h;
list = cache->providers;
/* Remove the stale cache entry if present. If not, we're * being called from outside of a request; remove the * non-stale handle.
*/
h = cache->stale_handle ? cache->stale_handle : cache->handle; if (!h) { return OK;
}
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00691) "cache: Removing url %s from the cache", h->cache_obj->key);
/* for each specified cache type, delete the URL */ while (list) {
list->provider->remove_url(h, r);
list = list->next;
} return OK;
}
/* * create a new URL entity in the cache * * It is possible to store more than once entity per URL. This * function will always create a new entity, regardless of whether * other entities already exist for the same URL. * * The size of the entity is provided so that a cache module can * decide whether or not it wants to cache this particular entity. * If the size is unknown, a size of -1 should be set.
*/ int cache_create_entity(cache_request_rec *cache, request_rec *r,
apr_off_t size, apr_bucket_brigade *in)
{
cache_provider_list *list;
cache_handle_t *h = apr_pcalloc(r->pool, sizeof(cache_handle_t));
apr_status_t rv;
if (!cache) { /* This should never happen */
ap_log_rerror(APLOG_MARK, APLOG_ERR, APR_EGENERAL, r, APLOGNO(00692) "cache: No cache request information available for key" " generation"); return APR_EGENERAL;
}
if (!cache->key) {
rv = cache_generate_key(r, r->pool, &cache->key); if (rv != APR_SUCCESS) { return rv;
}
}
list = cache->providers; /* for each specified cache type, delete the URL */ while (list) { switch (rv = list->provider->create_entity(h, r, cache->key, size, in)) { case OK: {
cache->handle = h;
cache->provider = list->provider;
cache->provider_name = list->provider_name; return OK;
} case DECLINED: {
list = list->next; continue;
} default: { return rv;
}
}
} return DECLINED;
}
staticint filter_header_do(void *v, constchar *key, constchar *val)
{ if ((*key == 'W' || *key == 'w') && !ap_cstr_casecmp(key, "Warning")
&& *val == '1') { /* any stored Warning headers with warn-code 1xx (see section * 14.46) MUST be deleted from the cache entry and the forwarded * response.
*/
} else {
apr_table_addn(v, key, val);
} return 1;
} staticint remove_header_do(void *v, constchar *key, constchar *val)
{ if ((*key == 'W' || *key == 'w') && !ap_cstr_casecmp(key, "Warning")) { /* any stored Warning headers with warn-code 2xx MUST be retained * in the cache entry and the forwarded response.
*/
} else {
apr_table_unset(v, key);
} return 1;
} staticint add_header_do(void *v, constchar *key, constchar *val)
{
apr_table_addn(v, key, val); return 1;
}
/** * Take two sets of headers, sandwich them together, and apply the result to * r->headers_out. * * To complicate this, a header may be duplicated in either table. Should a * header exist in the top table, all matching headers will be removed from * the bottom table before the headers are combined. The Warning headers are * handled specially. Warnings are added rather than being replaced, while * in the case of revalidation 1xx Warnings are stripped. * * The Content-Type and Last-Modified headers are then re-parsed and inserted * into the request.
*/ void cache_accept_headers(cache_handle_t *h, request_rec *r, apr_table_t *top,
apr_table_t *bottom, int revalidation)
{ constchar *v;
v = apr_table_get(r->headers_out, "Content-Type"); if (v) {
ap_set_content_type(r, v); /* * Also unset possible Content-Type headers in r->headers_out and * r->err_headers_out as they may be different to what we have received * from the cache. * Actually they are not needed as r->content_type set by * ap_set_content_type above will be used in the store_headers functions * of the storage providers as a fallback and the HTTP_HEADER filter * does overwrite the Content-Type header with r->content_type anyway.
*/
apr_table_unset(r->headers_out, "Content-Type");
apr_table_unset(r->err_headers_out, "Content-Type");
}
/* If the cache gave us a Last-Modified header, we can't just * pass it on blindly because of restrictions on future values.
*/
v = apr_table_get(r->headers_out, "Last-Modified"); if (v) {
ap_update_mtime(r, apr_date_parse_http(v));
ap_set_last_modified(r);
}
}
/* * select a specific URL entity in the cache * * It is possible to store more than one entity per URL. Content * negotiation is used to select an entity. Once an entity is * selected, details of it are stored in the per request * config to save time when serving the request later. * * This function returns OK if successful, DECLINED if no * cached entity fits the bill.
*/ int cache_select(cache_request_rec *cache, request_rec *r)
{
cache_provider_list *list;
apr_status_t rv;
cache_handle_t *h;
if (!cache) { /* This should never happen */
ap_log_rerror(APLOG_MARK, APLOG_ERR, APR_EGENERAL, r, APLOGNO(00693) "cache: No cache request information available for key" " generation"); return DECLINED;
}
/* if no-cache, we can't serve from the cache, but we may store to the * cache.
*/ if (!ap_cache_check_no_cache(cache, r)) { return DECLINED;
}
if (!cache->key) {
rv = cache_generate_key(r, r->pool, &cache->key); if (rv != APR_SUCCESS) { return DECLINED;
}
}
/* go through the cache types till we get a match */
h = apr_palloc(r->pool, sizeof(cache_handle_t));
list = cache->providers;
while (list) { switch ((rv = list->provider->open_entity(h, r, cache->key))) { case OK: { char *vary = NULL; int mismatch = 0; char *last = NULL;
if (list->provider->recall_headers(h, r) != APR_SUCCESS) { /* try again with next cache type */
list = list->next; continue;
}
/* * Check Content-Negotiation - Vary * * At this point we need to make sure that the object we found in * the cache is the same object that would be delivered to the * client, when the effects of content negotiation are taken into * effect. * * In plain english, we want to make sure that a language-negotiated * document in one language is not given to a client asking for a * language negotiated document in a different language by mistake. * * This code makes the assumption that the storage manager will * cache the req_hdrs if the response contains a Vary header. * * RFC2616 13.6 and 14.44 describe the Vary mechanism.
*/
vary = cache_strqtok(
apr_pstrdup(r->pool,
cache_table_getm(r->pool, h->resp_hdrs, "Vary")),
CACHE_SEPARATOR, &last); while (vary) { constchar *h1, *h2;
/* * is this header in the request and the header in the cached * request identical? If not, we give up and do a straight get
*/
h1 = cache_table_getm(r->pool, r->headers_in, vary);
h2 = cache_table_getm(r->pool, h->req_hdrs, vary); if (h1 == h2) { /* both headers NULL, so a match - do nothing */
} elseif (h1 && h2 && !strcmp(h1, h2)) { /* both headers exist and are equal - do nothing */
} else { /* headers do not match, so Vary failed */
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS,
r, APLOGNO(00694) "cache_select(): Vary header mismatch.");
mismatch = 1; break;
}
vary = cache_strqtok(NULL, CACHE_SEPARATOR, &last);
}
/* no vary match, try next provider */ if (mismatch) { /* try again with next cache type */
list = list->next; continue;
}
/* * RFC2616 13.3.4 Rules for When to Use Entity Tags and Last-Modified * Dates: An HTTP/1.1 caching proxy, upon receiving a conditional request * that includes both a Last-Modified date and one or more entity tags as * cache validators, MUST NOT return a locally cached response to the * client unless that cached response is consistent with all of the * conditional header fields in the request.
*/ if (ap_condition_if_match(r, h->resp_hdrs) == AP_CONDITION_NOMATCH
|| ap_condition_if_unmodified_since(r, h->resp_hdrs)
== AP_CONDITION_NOMATCH
|| ap_condition_if_none_match(r, h->resp_hdrs)
== AP_CONDITION_NOMATCH
|| ap_condition_if_modified_since(r, h->resp_hdrs)
== AP_CONDITION_NOMATCH
|| ap_condition_if_range(r, h->resp_hdrs) == AP_CONDITION_NOMATCH) {
mismatch = 1;
}
/* Is our cached response fresh enough? */ if (mismatch || !cache_check_freshness(h, cache, r)) { constchar *etag, *lastmod;
/* Cache-Control: only-if-cached and revalidation required, try * the next provider
*/ if (cache->control_in.only_if_cached) { /* try again with next cache type */
list = list->next; continue;
}
/* set aside the stale entry for accessing later */
cache->stale_headers = apr_table_copy(r->pool,
r->headers_in);
cache->stale_handle = h;
/* if no existing conditionals, use conditionals of our own */ if (!mismatch) {
if (etag || lastmod) { /* If we have a cached etag and/or Last-Modified add in * our own conditionals.
*/
if (etag) {
apr_table_set(r->headers_in, "If-None-Match", etag);
}
if (lastmod) {
apr_table_set(r->headers_in, "If-Modified-Since",
lastmod);
}
/* * Do not do Range requests with our own conditionals: If * we get 304 the Range does not matter and otherwise the * entity changed and we want to have the complete entity
*/
apr_table_unset(r->headers_in, "Range");
}
}
/* ready to revalidate, pretend we were never here */ return DECLINED;
}
/* Okay, this response looks okay. Merge in our stuff and go. */
cache_accept_headers(h, r, h->resp_hdrs, r->headers_out, 0);
cache->handle = h; return OK;
} case DECLINED: { /* try again with next cache type */
list = list->next; continue;
} default: { /* oo-er! an error */ return rv;
}
}
}
/* if Cache-Control: only-if-cached, and not cached, return 504 */ if (cache->control_in.only_if_cached) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(00696) "cache: 'only-if-cached' requested and no cached entity, " "returning 504 Gateway Timeout for: %s", r->uri); return HTTP_GATEWAY_TIME_OUT;
}
if (*key) { /* * We have been here before during the processing of this request.
*/ return APR_SUCCESS;
}
/* * Get the module configuration. We need this for the CacheIgnoreQueryString * option below.
*/
conf = (cache_server_conf *) ap_get_module_config(r->server->module_config,
&cache_module);
/* * Use the canonical name to improve cache hit rate, but only if this is * not a proxy request or if this is a reverse proxy request. * We need to handle both cases in the same manner as for the reverse proxy * case we have the following situation: * * If a cached entry is looked up by mod_cache's quick handler r->proxyreq * is still unset in the reverse proxy case as it only gets set in the * translate name hook (either by ProxyPass or mod_rewrite) which is run * after the quick handler hook. This is different to the forward proxy * case where it gets set before the quick handler is run (in the * post_read_request hook). * If a cache entry is created by the CACHE_SAVE filter we always have * r->proxyreq set correctly. * So we must ensure that in the reverse proxy case we use the same code * path and using the canonical name seems to be the right thing to do * in the reverse proxy case.
*/ if (!r->proxyreq || (r->proxyreq == PROXYREQ_REVERSE)) { if (conf->base_uri && conf->base_uri->hostname) {
hostname = conf->base_uri->hostname;
} else { /* Use _default_ as the hostname if none present, as in mod_vhost */
hostname = ap_get_server_name(r); if (!hostname) {
hostname = "_default_";
}
}
} elseif (parsed_uri->hostname) { /* Copy the parsed uri hostname */
hn = apr_pstrdup(p, parsed_uri->hostname);
ap_str_tolower(hn); /* const work-around */
hostname = hn;
} else { /* We are a proxied request, with no hostname. Unlikely
* to get very far - but just in case */
hostname = "_default_";
}
/* * Copy the scheme, ensuring that it is lower case. If the parsed uri * contains no string or if this is not a proxy request get the http * scheme for this request. As r->parsed_uri.scheme is not set if this * is a reverse proxy request, it is ensured that the cases * "no proxy request" and "reverse proxy request" are handled in the same * manner (see above why this is needed).
*/ if (r->proxyreq && parsed_uri->scheme) { /* Copy the scheme and lower-case it */
lcs = apr_pstrdup(p, parsed_uri->scheme);
ap_str_tolower(lcs); /* const work-around */
scheme = lcs;
} else { if (conf->base_uri && conf->base_uri->scheme) {
scheme = conf->base_uri->scheme;
} else {
scheme = ap_http_scheme(r);
}
}
/* * If this is a proxy request, but not a reverse proxy request (see comment * above why these cases must be handled in the same manner), copy the * URI's port-string (which may be a service name). If the URI contains * no port-string, use apr-util's notion of the default port for that * scheme - if available. Otherwise use the port-number of the current * server.
*/ if (r->proxyreq && (r->proxyreq != PROXYREQ_REVERSE)) { if (parsed_uri->port_str) {
port_str = apr_pcalloc(p, strlen(parsed_uri->port_str) + 2);
port_str[0] = ':'; for (i = 0; parsed_uri->port_str[i]; i++) {
port_str[i + 1] = apr_tolower(parsed_uri->port_str[i]);
}
} elseif (apr_uri_port_of_scheme(scheme)) {
port_str = apr_psprintf(p, ":%u", apr_uri_port_of_scheme(scheme));
} else { /* No port string given in the AbsoluteUri, and we have no * idea what the default port for the scheme is. Leave it * blank and live with the inefficiency of some extra cached * entities.
*/
port_str = "";
}
} else { if (conf->base_uri && conf->base_uri->port_str) {
port_str = apr_pstrcat(p, ":", conf->base_uri->port_str, NULL);
} elseif (conf->base_uri && conf->base_uri->hostname) {
port_str = "";
} else { /* Use the server port */
port_str = apr_psprintf(p, ":%u", ap_get_server_port(r));
}
}
/* * Check if we need to ignore session identifiers in the URL and do so * if needed.
*/
kpath = path;
kquery = conf->ignorequerystring ? NULL : query; if (conf->ignore_session_id->nelts) { int i; char **identifier;
identifier = (char **) conf->ignore_session_id->elts; for (i = 0; i < conf->ignore_session_id->nelts; i++, identifier++) { int len; constchar *param;
len = strlen(*identifier); /* * Check that we have a parameter separator in the last segment * of the path and that the parameter matches our identifier
*/ if ((param = ap_strrchr_c(kpath, ';'))
&& !strncmp(param + 1, *identifier, len)
&& (*(param + len + 1) == '=')
&& !ap_strchr_c(param + len + 2, '/')) {
kpath = apr_pstrmemdup(p, kpath, param - kpath); continue;
} /* * Check if the identifier is in the query string and cut it out.
*/ if (kquery && *kquery) { /* * First check if the identifier is at the beginning of the * query string and followed by a '='
*/ if (!strncmp(kquery, *identifier, len) && kquery[len] == '=') {
param = kquery;
} else { char *complete;
/* * In order to avoid subkey matching (PR 48401) prepend * identifier with a '&' and append a '='
*/
complete = apr_pstrcat(p, "&", *identifier, "=", NULL);
param = ap_strstr_c(kquery, complete); /* If we found something we are sitting on the '&' */ if (param) {
param++;
}
} if (param) { constchar *amp; char *dup = NULL;
if ((amp = ap_strchr_c(param + len + 1, '&'))) {
kquery = apr_pstrcat(p, kquery, amp + 1, NULL);
} else { /* * If query string is not "", then we have the case * that the identifier parameter we removed was the * last one in the original query string. Hence we have * a trailing '&' which needs to be removed.
*/ if (dup) {
dup[strlen(dup) - 1] = '\0';
}
}
}
}
}
}
/* Key format is a URI, optionally without the query-string (NULL * per above if conf->ignorequerystring)
*/
*key = apr_pstrcat(p, scheme, "://", hostname, port_str,
kpath, "?", kquery, NULL);
/* * Store the key in the request_config for the cache as r->parsed_uri * might have changed in the time from our first visit here triggered by the * quick handler and our possible second visit triggered by the CACHE_SAVE * filter (e.g. r->parsed_uri got unescaped). In this case we would save the * resource in the cache under a key where it is never found by the quick * handler during following requests.
*/
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(00698) "cache: Key for entity %s?%s is %s", path, query, *key);
return APR_SUCCESS;
}
apr_status_t cache_generate_key_default(request_rec *r, apr_pool_t* p, constchar **key)
{ /* In early processing (quick-handler, forward proxy), we want the initial * query-string from r->parsed_uri, since any change before CACHE_SAVE * shouldn't modify the key. Otherwise we want the actual query-string.
*/ constchar *path = r->uri; constchar *query = r->args; if (cache_use_early_url(r)) {
path = r->parsed_uri.path;
query = r->parsed_uri.query;
} return cache_canonicalise_key(r, p, path, query, &r->parsed_uri, key);
}
/* * Invalidate a specific URL entity in all caches * * All cached entities for this URL are removed, usually in * response to a POST/PUT or DELETE. * * This function returns OK if at least one entity was found and * removed, and DECLINED if no cached entities were removed.
*/ int cache_invalidate(cache_request_rec *cache, request_rec *r)
{
cache_provider_list *list;
apr_status_t rv, status = DECLINED;
cache_handle_t *h;
apr_uri_t location_uri;
apr_uri_t content_location_uri;
if (!cache) { /* This should never happen */
ap_log_rerror(
APLOG_MARK, APLOG_ERR, APR_EGENERAL, r, APLOGNO(00697) "cache: No cache request information available for key" " generation"); return DECLINED;
}
if (!cache->key) {
rv = cache_generate_key(r, r->pool, &cache->key); if (rv != APR_SUCCESS) { return DECLINED;
}
}
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