/* 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. */ #define CORE_PRIVATE #include "mod_cache.h" module AP_MODULE_DECLARE_DATA cache_module; APR_OPTIONAL_FN_TYPE(ap_cache_generate_key) *cache_generate_key; /* -------------------------------------------------------------- */ /* Handles for cache filters, resolved at startup to eliminate * a name-to-function mapping on each request */ static ap_filter_rec_t *cache_save_filter_handle; static ap_filter_rec_t *cache_save_subreq_filter_handle; static ap_filter_rec_t *cache_out_filter_handle; static ap_filter_rec_t *cache_out_subreq_filter_handle; static ap_filter_rec_t *cache_remove_url_filter_handle; /* * CACHE handler * ------------- * * Can we deliver this request from the cache? * If yes: * deliver the content by installing the CACHE_OUT filter. * If no: * check whether we're allowed to try cache it * If yes: * add CACHE_SAVE filter * If No: * oh well. */ static int cache_url_handler(request_rec *r, int lookup) { apr_status_t rv; const char *auth; cache_provider_list *providers; cache_request_rec *cache; cache_server_conf *conf; apr_bucket_brigade *out; ap_filter_t *next; ap_filter_rec_t *cache_out_handle; /* Delay initialization until we know we are handling a GET */ if (r->method_number != M_GET) { return DECLINED; } conf = (cache_server_conf *) ap_get_module_config(r->server->module_config, &cache_module); /* * Which cache module (if any) should handle this request? */ if (!(providers = ap_cache_get_providers(r, conf, r->parsed_uri))) { return DECLINED; } /* make space for the per request config */ cache = (cache_request_rec *) ap_get_module_config(r->request_config, &cache_module); if (!cache) { cache = apr_pcalloc(r->pool, sizeof(cache_request_rec)); ap_set_module_config(r->request_config, &cache_module, cache); } /* save away the possible providers */ cache->providers = providers; /* * Are we allowed to serve cached info at all? */ /* find certain cache controlling headers */ auth = apr_table_get(r->headers_in, "Authorization"); /* First things first - does the request allow us to return * cached information at all? If not, just decline the request. */ if (auth) { return DECLINED; } /* * Try to serve this request from the cache. * * If no existing cache file (DECLINED) * add cache_save filter * If cached file (OK) * clear filter stack * add cache_out filter * return OK */ rv = cache_select(r); if (rv != OK) { if (rv == DECLINED) { if (!lookup) { /* * Add cache_save filter to cache this request. Choose * the correct filter by checking if we are a subrequest * or not. */ if (r->main) { ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r->server, "Adding CACHE_SAVE_SUBREQ filter for %s", r->uri); ap_add_output_filter_handle(cache_save_subreq_filter_handle, NULL, r, r->connection); } else { ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r->server, "Adding CACHE_SAVE filter for %s", r->uri); ap_add_output_filter_handle(cache_save_filter_handle, NULL, r, r->connection); } ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r->server, "Adding CACHE_REMOVE_URL filter for %s", r->uri); /* Add cache_remove_url filter to this request to remove a * stale cache entry if needed. Also put the current cache * request rec in the filter context, as the request that * is available later during running the filter maybe * different due to an internal redirect. */ cache->remove_url_filter = ap_add_output_filter_handle(cache_remove_url_filter_handle, cache, r, r->connection); } else { if (cache->stale_headers) { ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r->server, "Restoring request headers for %s", r->uri); r->headers_in = cache->stale_headers; } /* Delete our per-request configuration. */ ap_set_module_config(r->request_config, &cache_module, NULL); } } else { /* error */ ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server, "cache: error returned while checking for cached " "file by %s cache", cache->provider_name); } return DECLINED; } /* if we are a lookup, we are exiting soon one way or another; Restore * the headers. */ if (lookup) { if (cache->stale_headers) { ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r->server, "Restoring request headers."); r->headers_in = cache->stale_headers; } /* Delete our per-request configuration. */ ap_set_module_config(r->request_config, &cache_module, NULL); } rv = ap_meets_conditions(r); if (rv != OK) { /* If we are a lookup, we have to return DECLINED as we have no * way of knowing if we will be able to serve the content. */ if (lookup) { return DECLINED; } /* Return cached status. */ return rv; } /* If we're a lookup, we can exit now instead of serving the content. */ if (lookup) { return OK; } /* Serve up the content */ /* We are in the quick handler hook, which means that no output * filters have been set. So lets run the insert_filter hook. */ ap_run_insert_filter(r); /* * Add cache_out filter to serve this request. Choose * the correct filter by checking if we are a subrequest * or not. */ if (r->main) { cache_out_handle = cache_out_subreq_filter_handle; } else { cache_out_handle = cache_out_filter_handle; } ap_add_output_filter_handle(cache_out_handle, NULL, r, r->connection); /* * Remove all filters that are before the cache_out filter. This ensures * that we kick off the filter stack with our cache_out filter being the * first in the chain. This make sense because we want to restore things * in the same manner as we saved them. * There may be filters before our cache_out filter, because * * 1. We call ap_set_content_type during cache_select. This causes * Content-Type specific filters to be added. * 2. We call the insert_filter hook. This causes filters e.g. like * the ones set with SetOutputFilter to be added. */ next = r->output_filters; while (next && (next->frec != cache_out_handle)) { ap_remove_output_filter(next); next = next->next; } /* kick off the filter stack */ out = apr_brigade_create(r->pool, r->connection->bucket_alloc); rv = ap_pass_brigade(r->output_filters, out); if (rv != APR_SUCCESS) { if (rv != AP_FILTER_ERROR) { ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server, "cache: error returned while trying to return %s " "cached data", cache->provider_name); } return rv; } return OK; } /* * CACHE_OUT filter * ---------------- * * Deliver cached content (headers and body) up the stack. */ static int cache_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { request_rec *r = f->r; cache_request_rec *cache; cache = (cache_request_rec *) ap_get_module_config(r->request_config, &cache_module); if (!cache) { /* user likely configured CACHE_OUT manually; they should use mod_cache * configuration to do that */ ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server, "CACHE_OUT enabled unexpectedly"); ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r->server, "cache: running CACHE_OUT filter"); /* restore status of cached response */ /* XXX: This exposes a bug in mem_cache, since it does not * restore the status into it's handle. */ r->status = cache->handle->cache_obj->info.status; /* recall_headers() was called in cache_select() */ cache->provider->recall_body(cache->handle, r->pool, bb); /* This filter is done once it has served up its content */ ap_remove_output_filter(f); ap_log_error(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r->server, "cache: serving %s", r->uri); return ap_pass_brigade(f->next, bb); } /* * CACHE_SAVE filter * --------------- * * Decide whether or not this content should be cached. * If we decide no it should not: * remove the filter from the chain * If we decide yes it should: * Have we already started saving the response? * If we have started, pass the data to the storage manager via store_body * Otherwise: * Check to see if we *can* save this particular response. * If we can, call cache_create_entity() and save the headers and body * Finally, pass the data to the next filter (the network or whatever) */ static int cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in) { int rv = !OK; request_rec *r = f->r; cache_request_rec *cache; cache_server_conf *conf; const char *cc_out, *cl; const char *exps, *lastmods, *dates, *etag; apr_time_t exp, date, lastmod, now; apr_off_t size; cache_info *info = NULL; char *reason; apr_pool_t *p; conf = (cache_server_conf *) ap_get_module_config(r->server->module_config, &cache_module); /* Setup cache_request_rec */ cache = (cache_request_rec *) ap_get_module_config(r->request_config, &cache_module); if (!cache) { /* user likely configured CACHE_SAVE manually; they should really use * mod_cache configuration to do that */ cache = apr_pcalloc(r->pool, sizeof(cache_request_rec)); ap_set_module_config(r->request_config, &cache_module, cache); } reason = NULL; p = r->pool; /* * Pass Data to Cache * ------------------ * This section passes the brigades into the cache modules, but only * if the setup section (see below) is complete. */ if (cache->block_response) { /* We've already sent down the response and EOS. So, ignore * whatever comes now. */ return APR_SUCCESS; } /* have we already run the cachability check and set up the * cached file handle? */ if (cache->in_checked) { /* pass the brigades into the cache, then pass them * up the filter stack */ rv = cache->provider->store_body(cache->handle, r, in); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_DEBUG, rv, r->server, "cache: Cache provider's store_body failed!"); ap_remove_output_filter(f); } return ap_pass_brigade(f->next, in); } /* * Setup Data in Cache * ------------------- * This section opens the cache entity and sets various caching * parameters, and decides whether this URL should be cached at * all. This section is* run before the above section. */ /* read expiry date; if a bad date, then leave it so the client can * read it */ exps = apr_table_get(r->err_headers_out, "Expires"); if (exps == NULL) { exps = apr_table_get(r->headers_out, "Expires"); } if (exps != NULL) { if (APR_DATE_BAD == (exp = apr_date_parse_http(exps))) { exps = NULL; } } else { exp = APR_DATE_BAD; } /* read the last-modified date; if the date is bad, then delete it */ lastmods = apr_table_get(r->err_headers_out, "Last-Modified"); if (lastmods == NULL) { lastmods = apr_table_get(r->headers_out, "Last-Modified"); } if (lastmods != NULL) { lastmod = apr_date_parse_http(lastmods); if (lastmod == APR_DATE_BAD) { lastmods = NULL; } } else { lastmod = APR_DATE_BAD; } /* read the etag and cache-control from the entity */ etag = apr_table_get(r->err_headers_out, "Etag"); if (etag == NULL) { etag = apr_table_get(r->headers_out, "Etag"); } cc_out = apr_table_get(r->err_headers_out, "Cache-Control"); if (cc_out == NULL) { cc_out = apr_table_get(r->headers_out, "Cache-Control"); } /* * what responses should we not cache? * * At this point we decide based on the response headers whether it * is appropriate _NOT_ to cache the data from the server. There are * a whole lot of conditions that prevent us from caching this data. * They are tested here one by one to be clear and unambiguous. */ if (r->status != HTTP_OK && r->status != HTTP_NON_AUTHORITATIVE && r->status != HTTP_MULTIPLE_CHOICES && r->status != HTTP_MOVED_PERMANENTLY && r->status != HTTP_NOT_MODIFIED) { /* RFC2616 13.4 we are allowed to cache 200, 203, 206, 300, 301 or 410 * We don't cache 206, because we don't (yet) cache partial responses. * We include 304 Not Modified here too as this is the origin server * telling us to serve the cached copy. */ reason = apr_psprintf(p, "Response status %d", r->status); } else if (exps != NULL && exp == APR_DATE_BAD) { /* if a broken Expires header is present, don't cache it */ reason = apr_pstrcat(p, "Broken expires header: ", exps, NULL); } else if (exp != APR_DATE_BAD && exp < r->request_time) { /* if a Expires header is in the past, don't cache it */ reason = "Expires header already expired, not cacheable"; } else if (!conf->ignorequerystring && r->parsed_uri.query && exps == NULL && !ap_cache_liststr(NULL, cc_out, "max-age", NULL)) { /* if a query string is present but no explicit expiration time, * don't cache it (RFC 2616/13.9 & 13.2.1) */ reason = "Query string present but no explicit expiration time"; } else if (r->status == HTTP_NOT_MODIFIED && !cache->handle && !cache->stale_handle) { /* if the server said 304 Not Modified but we have no cache * file - pass this untouched to the user agent, it's not for us. */ reason = "HTTP Status 304 Not Modified"; } else if (r->status == HTTP_OK && lastmods == NULL && etag == NULL && (exps == NULL) && (conf->no_last_mod_ignore ==0)) { /* 200 OK response from HTTP/1.0 and up without Last-Modified, * Etag, or Expires headers. */ /* Note: mod-include clears last_modified/expires/etags - this * is why we have an optional function for a key-gen ;-) */ reason = "No Last-Modified, Etag, or Expires headers"; } else if (r->header_only && !cache->stale_handle) { /* Forbid HEAD requests unless we have it cached already */ reason = "HTTP HEAD request"; } else if (!conf->store_nostore && ap_cache_liststr(NULL, cc_out, "no-store", NULL)) { /* RFC2616 14.9.2 Cache-Control: no-store response * indicating do not cache, or stop now if you are * trying to cache it. */ /* FIXME: The Cache-Control: no-store could have come in on a 304, * FIXME: while the original request wasn't conditional. IOW, we * FIXME: made the the request conditional earlier to revalidate * FIXME: our cached response. */ reason = "Cache-Control: no-store present"; } else if (!conf->store_private && ap_cache_liststr(NULL, cc_out, "private", NULL)) { /* RFC2616 14.9.1 Cache-Control: private response * this object is marked for this user's eyes only. Behave * as a tunnel. */ /* FIXME: See above (no-store) */ reason = "Cache-Control: private present"; } else if (apr_table_get(r->headers_in, "Authorization") != NULL && !(ap_cache_liststr(NULL, cc_out, "s-maxage", NULL) || ap_cache_liststr(NULL, cc_out, "must-revalidate", NULL) || ap_cache_liststr(NULL, cc_out, "public", NULL))) { /* RFC2616 14.8 Authorisation: * if authorisation is included in the request, we don't cache, * but we can cache if the following exceptions are true: * 1) If Cache-Control: s-maxage is included * 2) If Cache-Control: must-revalidate is included * 3) If Cache-Control: public is included */ reason = "Authorization required"; } else if (ap_cache_liststr(NULL, apr_table_get(r->headers_out, "Vary"), "*", NULL)) { reason = "Vary header contains '*'"; } else if (r->no_cache) { /* or we've been asked not to cache it above */ reason = "r->no_cache present"; } if (reason) { ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "cache: %s not cached. Reason: %s", r->unparsed_uri, reason); /* remove this filter from the chain */ ap_remove_output_filter(f); /* ship the data up the stack */ return ap_pass_brigade(f->next, in); } /* Make it so that we don't execute this path again. */ cache->in_checked = 1; /* Set the content length if known. */ cl = apr_table_get(r->err_headers_out, "Content-Length"); if (cl == NULL) { cl = apr_table_get(r->headers_out, "Content-Length"); } if (cl) { char *errp; if (apr_strtoff(&size, cl, &errp, 10) || *errp || size < 0) { cl = NULL; /* parse error, see next 'if' block */ } } if (!cl) { /* if we don't get the content-length, see if we have all the * buckets and use their length to calculate the size */ apr_bucket *e; int all_buckets_here=0; int unresolved_length = 0; size=0; for (e = APR_BRIGADE_FIRST(in); e != APR_BRIGADE_SENTINEL(in); e = APR_BUCKET_NEXT(e)) { if (APR_BUCKET_IS_EOS(e)) { all_buckets_here=1; break; } if (APR_BUCKET_IS_FLUSH(e)) { unresolved_length = 1; continue; } if (e->length == (apr_size_t)-1) { break; } size += e->length; } if (!all_buckets_here) { size = -1; } } /* It's safe to cache the response. * * There are two possiblities at this point: * - cache->handle == NULL. In this case there is no previously * cached entity anywhere on the system. We must create a brand * new entity and store the response in it. * - cache->stale_handle != NULL. In this case there is a stale * entity in the system which needs to be replaced by new * content (unless the result was 304 Not Modified, which means * the cached entity is actually fresh, and we should update * the headers). */ /* Did we have a stale cache entry that really is stale? * * Note that for HEAD requests, we won't get the body, so for a stale * HEAD request, we don't remove the entity - instead we let the * CACHE_REMOVE_URL filter remove the stale item from the cache. */ if (cache->stale_handle) { if (r->status == HTTP_NOT_MODIFIED) { /* Oh, hey. It isn't that stale! Yay! */ cache->handle = cache->stale_handle; info = &cache->handle->cache_obj->info; rv = OK; } else if (!r->header_only) { /* Oh, well. Toss it. */ cache->provider->remove_entity(cache->stale_handle); /* Treat the request as if it wasn't conditional. */ cache->stale_handle = NULL; /* * Restore the original request headers as they may be needed * by further output filters like the byterange filter to make * the correct decisions. */ r->headers_in = cache->stale_headers; } } /* no cache handle, create a new entity only for non-HEAD requests */ if (!cache->handle && !r->header_only) { rv = cache_create_entity(r, size); info = apr_pcalloc(r->pool, sizeof(cache_info)); /* We only set info->status upon the initial creation. */ info->status = r->status; } if (rv != OK) { /* Caching layer declined the opportunity to cache the response */ ap_remove_output_filter(f); return ap_pass_brigade(f->next, in); } ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "cache: Caching url: %s", r->unparsed_uri); /* We are actually caching this response. So it does not * make sense to remove this entity any more. */ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "cache: Removing CACHE_REMOVE_URL filter."); ap_remove_output_filter(cache->remove_url_filter); /* * We now want to update the cache file header information with * the new date, last modified, expire and content length and write * it away to our cache file. First, we determine these values from * the response, using heuristics if appropriate. * * In addition, we make HTTP/1.1 age calculations and write them away * too. */ /* Read the date. Generate one if one is not supplied */ dates = apr_table_get(r->err_headers_out, "Date"); if (dates == NULL) { dates = apr_table_get(r->headers_out, "Date"); } if (dates != NULL) { info->date = apr_date_parse_http(dates); } else { info->date = APR_DATE_BAD; } now = apr_time_now(); if (info->date == APR_DATE_BAD) { /* No, or bad date */ /* no date header (or bad header)! */ info->date = now; } date = info->date; /* set response_time for HTTP/1.1 age calculations */ info->response_time = now; /* get the request time */ info->request_time = r->request_time; /* check last-modified date */ if (lastmod != APR_DATE_BAD && lastmod > date) { /* if it's in the future, then replace by date */ lastmod = date; lastmods = dates; ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "cache: Last modified is in the future, " "replacing with now"); } /* if no expiry date then * if Cache-Control: max-age present * expiry date = date + max-age * else if lastmod * expiry date = date + min((date - lastmod) * factor, maxexpire) * else * expire date = date + defaultexpire */ if (exp == APR_DATE_BAD) { char *max_age_val; if (ap_cache_liststr(r->pool, cc_out, "max-age", &max_age_val) && max_age_val != NULL) { apr_int64_t x; errno = 0; x = apr_atoi64(max_age_val); if (errno) { x = conf->defex; } else { x = x * MSEC_ONE_SEC; } if (x > conf->maxex) { x = conf->maxex; } exp = date + x; } else if ((lastmod != APR_DATE_BAD) && (lastmod < date)) { /* if lastmod == date then you get 0*conf->factor which results in * an expiration time of now. This causes some problems with * freshness calculations, so we choose the else path... */ apr_time_t x = (apr_time_t) ((date - lastmod) * conf->factor); if (x > conf->maxex) { x = conf->maxex; } exp = date + x; } else { exp = date + conf->defex; } } info->expire = exp; /* We found a stale entry which wasn't really stale. */ if (cache->stale_handle) { /* Load in the saved status and clear the status line. */ r->status = info->status; r->status_line = NULL; /* RFC 2616 10.3.5 states that entity headers are not supposed * to be in the 304 response. Therefore, we need to combine the * response headers with the cached headers *before* we update * the cached headers. * * However, before doing that, we need to first merge in * err_headers_out and we also need to strip any hop-by-hop * headers that might have snuck in. */ r->headers_out = apr_table_overlay(r->pool, r->headers_out, r->err_headers_out); r->headers_out = ap_cache_cacheable_hdrs_out(r->pool, r->headers_out, r->server); apr_table_clear(r->err_headers_out); /* Merge in our cached headers. However, keep any updated values. */ ap_cache_accept_headers(cache->handle, r, 1); } /* Write away header information to cache. It is possible that we are * trying to update headers for an entity which has already been cached. * * This may fail, due to an unwritable cache area. E.g. filesystem full, * permissions problems or a read-only (re)mount. This must be handled * later. */ rv = cache->provider->store_headers(cache->handle, r, info); /* Did we just update the cached headers on a revalidated response? * * If so, we can now decide what to serve to the client. This is done in * the same way as with a regular response, but conditions are now checked * against the cached or merged response headers. */ if (cache->stale_handle) { apr_bucket_brigade *bb; apr_bucket *bkt; int status; bb = apr_brigade_create(r->pool, r->connection->bucket_alloc); /* Restore the original request headers and see if we need to * return anything else than the cached response (ie. the original * request was conditional). */ r->headers_in = cache->stale_headers; status = ap_meets_conditions(r); if (status != OK) { r->status = status; bkt = apr_bucket_flush_create(bb->bucket_alloc); APR_BRIGADE_INSERT_TAIL(bb, bkt); } else { cache->provider->recall_body(cache->handle, r->pool, bb); } cache->block_response = 1; /* Before returning we need to handle the possible case of an * unwritable cache. Rather than leaving the entity in the cache * and having it constantly re-validated, now that we have recalled * the body it is safe to try and remove the url from the cache. */ if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_DEBUG, rv, r->server, "cache: updating headers with store_headers failed. " "Removing cached url."); rv = cache->provider->remove_url(cache->stale_handle, r->pool); if (rv != OK) { /* Probably a mod_disk_cache cache area has been (re)mounted * read-only, or that there is a permissions problem. */ ap_log_error(APLOG_MARK, APLOG_DEBUG, rv, r->server, "cache: attempt to remove url from cache unsuccessful."); } } return ap_pass_brigade(f->next, bb); } if(rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_DEBUG, rv, r->server, "cache: store_headers failed"); ap_remove_output_filter(f); return ap_pass_brigade(f->next, in); } rv = cache->provider->store_body(cache->handle, r, in); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_DEBUG, rv, r->server, "cache: store_body failed"); ap_remove_output_filter(f); } return ap_pass_brigade(f->next, in); } /* * CACHE_REMOVE_URL filter * --------------- * * This filter gets added in the quick handler every time the CACHE_SAVE filter * gets inserted. Its purpose is to remove a confirmed stale cache entry from * the cache. * * CACHE_REMOVE_URL has to be a protocol filter to ensure that is run even if * the response is a canned error message, which removes the content filters * and thus the CACHE_SAVE filter from the chain. * * CACHE_REMOVE_URL expects cache request rec within its context because the * request this filter runs on can be different from the one whose cache entry * should be removed, due to internal redirects. * * Note that CACHE_SAVE_URL (as a content-set filter, hence run before the * protocol filters) will remove this filter if it decides to cache the file. * Therefore, if this filter is left in, it must mean we need to toss any * existing files. */ static int cache_remove_url_filter(ap_filter_t *f, apr_bucket_brigade *in) { request_rec *r = f->r; cache_request_rec *cache; /* Setup cache_request_rec */ cache = (cache_request_rec *) f->ctx; if (!cache) { /* user likely configured CACHE_REMOVE_URL manually; they should really * use mod_cache configuration to do that. So: * 1. Remove ourselves * 2. Do nothing and bail out */ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "cache: CACHE_REMOVE_URL enabled unexpectedly"); ap_remove_output_filter(f); return ap_pass_brigade(f->next, in); } /* Now remove this cache entry from the cache */ cache_remove_url(cache, r->pool); /* remove ourselves */ ap_remove_output_filter(f); return ap_pass_brigade(f->next, in); } /* -------------------------------------------------------------- */ /* Setup configurable data */ static void * create_cache_config(apr_pool_t *p, server_rec *s) { cache_server_conf *ps = apr_pcalloc(p, sizeof(cache_server_conf)); /* array of URL prefixes for which caching is enabled */ ps->cacheenable = apr_array_make(p, 10, sizeof(struct cache_enable)); /* array of URL prefixes for which caching is disabled */ ps->cachedisable = apr_array_make(p, 10, sizeof(struct cache_disable)); /* maximum time to cache a document */ ps->maxex = DEFAULT_CACHE_MAXEXPIRE; ps->maxex_set = 0; /* default time to cache a document */ ps->defex = DEFAULT_CACHE_EXPIRE; ps->defex_set = 0; /* factor used to estimate Expires date from LastModified date */ ps->factor = DEFAULT_CACHE_LMFACTOR; ps->factor_set = 0; ps->no_last_mod_ignore_set = 0; ps->no_last_mod_ignore = 0; ps->ignorecachecontrol = 0; ps->ignorecachecontrol_set = 0; ps->store_private = 0; ps->store_private_set = 0; ps->store_nostore = 0; ps->store_nostore_set = 0; /* array of headers that should not be stored in cache */ ps->ignore_headers = apr_array_make(p, 10, sizeof(char *)); ps->ignore_headers_set = CACHE_IGNORE_HEADERS_UNSET; /* flag indicating that query-string should be ignored when caching */ ps->ignorequerystring = 0; ps->ignorequerystring_set = 0; return ps; } static void * merge_cache_config(apr_pool_t *p, void *basev, void *overridesv) { cache_server_conf *ps = apr_pcalloc(p, sizeof(cache_server_conf)); cache_server_conf *base = (cache_server_conf *) basev; cache_server_conf *overrides = (cache_server_conf *) overridesv; /* array of URL prefixes for which caching is disabled */ ps->cachedisable = apr_array_append(p, base->cachedisable, overrides->cachedisable); /* array of URL prefixes for which caching is enabled */ ps->cacheenable = apr_array_append(p, base->cacheenable, overrides->cacheenable); /* maximum time to cache a document */ ps->maxex = (overrides->maxex_set == 0) ? base->maxex : overrides->maxex; /* default time to cache a document */ ps->defex = (overrides->defex_set == 0) ? base->defex : overrides->defex; /* factor used to estimate Expires date from LastModified date */ ps->factor = (overrides->factor_set == 0) ? base->factor : overrides->factor; ps->no_last_mod_ignore = (overrides->no_last_mod_ignore_set == 0) ? base->no_last_mod_ignore : overrides->no_last_mod_ignore; ps->ignorecachecontrol = (overrides->ignorecachecontrol_set == 0) ? base->ignorecachecontrol : overrides->ignorecachecontrol; ps->store_private = (overrides->store_private_set == 0) ? base->store_private : overrides->store_private; ps->store_nostore = (overrides->store_nostore_set == 0) ? base->store_nostore : overrides->store_nostore; ps->ignore_headers = (overrides->ignore_headers_set == CACHE_IGNORE_HEADERS_UNSET) ? base->ignore_headers : overrides->ignore_headers; ps->ignorequerystring = (overrides->ignorequerystring_set == 0) ? base->ignorequerystring : overrides->ignorequerystring; return ps; } static const char *set_cache_ignore_no_last_mod(cmd_parms *parms, void *dummy, int flag) { cache_server_conf *conf; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); conf->no_last_mod_ignore = flag; conf->no_last_mod_ignore_set = 1; return NULL; } static const char *set_cache_ignore_cachecontrol(cmd_parms *parms, void *dummy, int flag) { cache_server_conf *conf; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); conf->ignorecachecontrol = flag; conf->ignorecachecontrol_set = 1; return NULL; } static const char *set_cache_store_private(cmd_parms *parms, void *dummy, int flag) { cache_server_conf *conf; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); conf->store_private = flag; conf->store_private_set = 1; return NULL; } static const char *set_cache_store_nostore(cmd_parms *parms, void *dummy, int flag) { cache_server_conf *conf; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); conf->store_nostore = flag; conf->store_nostore_set = 1; return NULL; } static const char *add_ignore_header(cmd_parms *parms, void *dummy, const char *header) { cache_server_conf *conf; char **new; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); if (!strncasecmp(header, "None", 4)) { /* if header None is listed clear array */ conf->ignore_headers->nelts = 0; } else { if ((conf->ignore_headers_set == CACHE_IGNORE_HEADERS_UNSET) || (conf->ignore_headers->nelts)) { /* Only add header if no "None" has been found in header list * so far. * (When 'None' is passed, IGNORE_HEADERS_SET && nelts == 0.) */ new = (char **)apr_array_push(conf->ignore_headers); (*new) = (char *)header; } } conf->ignore_headers_set = CACHE_IGNORE_HEADERS_SET; return NULL; } static const char *add_cache_enable(cmd_parms *parms, void *dummy, const char *type, const char *url) { cache_server_conf *conf; struct cache_enable *new; if (*type == '/') { return apr_psprintf(parms->pool, "provider (%s) starts with a '/'. Are url and provider switched?", type); } conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); new = apr_array_push(conf->cacheenable); new->type = type; if (apr_uri_parse(parms->pool, url, &(new->url))) { return NULL; } if (new->url.path) { new->pathlen = strlen(new->url.path); } else { new->pathlen = 1; new->url.path = "/"; } return NULL; } static const char *add_cache_disable(cmd_parms *parms, void *dummy, const char *url) { cache_server_conf *conf; struct cache_disable *new; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); new = apr_array_push(conf->cachedisable); if (apr_uri_parse(parms->pool, url, &(new->url))) { return NULL; } if (new->url.path) { new->pathlen = strlen(new->url.path); } else { new->pathlen = 1; new->url.path = "/"; } return NULL; } static const char *set_cache_maxex(cmd_parms *parms, void *dummy, const char *arg) { cache_server_conf *conf; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); conf->maxex = (apr_time_t) (atol(arg) * MSEC_ONE_SEC); conf->maxex_set = 1; return NULL; } static const char *set_cache_defex(cmd_parms *parms, void *dummy, const char *arg) { cache_server_conf *conf; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); conf->defex = (apr_time_t) (atol(arg) * MSEC_ONE_SEC); conf->defex_set = 1; return NULL; } static const char *set_cache_factor(cmd_parms *parms, void *dummy, const char *arg) { cache_server_conf *conf; double val; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); if (sscanf(arg, "%lg", &val) != 1) { return "CacheLastModifiedFactor value must be a float"; } conf->factor = val; conf->factor_set = 1; return NULL; } static const char *set_cache_ignore_querystring(cmd_parms *parms, void *dummy, int flag) { cache_server_conf *conf; conf = (cache_server_conf *)ap_get_module_config(parms->server->module_config, &cache_module); conf->ignorequerystring = flag; conf->ignorequerystring_set = 1; return NULL; } static int cache_post_config(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s) { /* This is the means by which unusual (non-unix) os's may find alternate * means to run a given command (e.g. shebang/registry parsing on Win32) */ cache_generate_key = APR_RETRIEVE_OPTIONAL_FN(ap_cache_generate_key); if (!cache_generate_key) { cache_generate_key = cache_generate_key_default; } return OK; } static const command_rec cache_cmds[] = { /* XXX * Consider a new config directive that enables loading specific cache * implememtations (like mod_cache_mem, mod_cache_file, etc.). * Rather than using a LoadModule directive, admin would use something * like CacheModule mem_cache_module | file_cache_module, etc, * which would cause the approprpriate cache module to be loaded. * This is more intuitive that requiring a LoadModule directive. */ AP_INIT_TAKE2("CacheEnable", add_cache_enable, NULL, RSRC_CONF, "A cache type and partial URL prefix below which " "caching is enabled"), AP_INIT_TAKE1("CacheDisable", add_cache_disable, NULL, RSRC_CONF, "A partial URL prefix below which caching is disabled"), AP_INIT_TAKE1("CacheMaxExpire", set_cache_maxex, NULL, RSRC_CONF, "The maximum time in seconds to cache a document"), AP_INIT_TAKE1("CacheDefaultExpire", set_cache_defex, NULL, RSRC_CONF, "The default time in seconds to cache a document"), AP_INIT_FLAG("CacheIgnoreNoLastMod", set_cache_ignore_no_last_mod, NULL, RSRC_CONF, "Ignore Responses where there is no Last Modified Header"), AP_INIT_FLAG("CacheIgnoreCacheControl", set_cache_ignore_cachecontrol, NULL, RSRC_CONF, "Ignore requests from the client for uncached content"), AP_INIT_FLAG("CacheStorePrivate", set_cache_store_private, NULL, RSRC_CONF, "Ignore 'Cache-Control: private' and store private content"), AP_INIT_FLAG("CacheStoreNoStore", set_cache_store_nostore, NULL, RSRC_CONF, "Ignore 'Cache-Control: no-store' and store sensitive content"), AP_INIT_ITERATE("CacheIgnoreHeaders", add_ignore_header, NULL, RSRC_CONF, "A space separated list of headers that should not be " "stored by the cache"), AP_INIT_FLAG("CacheIgnoreQueryString", set_cache_ignore_querystring, NULL, RSRC_CONF, "Ignore query-string when caching"), AP_INIT_TAKE1("CacheLastModifiedFactor", set_cache_factor, NULL, RSRC_CONF, "The factor used to estimate Expires date from " "LastModified date"), {NULL} }; static void register_hooks(apr_pool_t *p) { /* cache initializer */ /* cache handler */ ap_hook_quick_handler(cache_url_handler, NULL, NULL, APR_HOOK_FIRST); /* cache filters * XXX The cache filters need to run right after the handlers and before * any other filters. Consider creating AP_FTYPE_CACHE for this purpose. * * Depending on the type of request (subrequest / main request) they * need to be run before AP_FTYPE_CONTENT_SET / after AP_FTYPE_CONTENT_SET * filters. Thus create two filter handles for each type: * cache_save_filter_handle / cache_out_filter_handle to be used by * main requests and * cache_save_subreq_filter_handle / cache_out_subreq_filter_handle * to be run by subrequest */ /* * CACHE_SAVE must go into the filter chain after a possible DEFLATE * filter to ensure that the compressed content is stored. * Incrementing filter type by 1 ensures his happens. */ cache_save_filter_handle = ap_register_output_filter("CACHE_SAVE", cache_save_filter, NULL, AP_FTYPE_CONTENT_SET+1); /* * CACHE_SAVE_SUBREQ must go into the filter chain before SUBREQ_CORE to * handle subrequsts. Decrementing filter type by 1 ensures this * happens. */ cache_save_subreq_filter_handle = ap_register_output_filter("CACHE_SAVE_SUBREQ", cache_save_filter, NULL, AP_FTYPE_CONTENT_SET-1); /* * CACHE_OUT must go into the filter chain after a possible DEFLATE * filter to ensure that already compressed cache objects do not * get compressed again. Incrementing filter type by 1 ensures * his happens. */ cache_out_filter_handle = ap_register_output_filter("CACHE_OUT", cache_out_filter, NULL, AP_FTYPE_CONTENT_SET+1); /* * CACHE_OUT_SUBREQ must go into the filter chain before SUBREQ_CORE to * handle subrequsts. Decrementing filter type by 1 ensures this * happens. */ cache_out_subreq_filter_handle = ap_register_output_filter("CACHE_OUT_SUBREQ", cache_out_filter, NULL, AP_FTYPE_CONTENT_SET-1); /* CACHE_REMOVE_URL has to be a protocol filter to ensure that is * run even if the response is a canned error message, which * removes the content filters. */ cache_remove_url_filter_handle = ap_register_output_filter("CACHE_REMOVE_URL", cache_remove_url_filter, NULL, AP_FTYPE_PROTOCOL); ap_hook_post_config(cache_post_config, NULL, NULL, APR_HOOK_REALLY_FIRST); } module AP_MODULE_DECLARE_DATA cache_module = { STANDARD20_MODULE_STUFF, NULL, /* create per-directory config structure */ NULL, /* merge per-directory config structures */ create_cache_config, /* create per-server config structure */ merge_cache_config, /* merge per-server config structures */ cache_cmds, /* command apr_table_t */ register_hooks };