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-rw-r--r--modules/cache/mod_cache.c393
1 files changed, 297 insertions, 96 deletions
diff --git a/modules/cache/mod_cache.c b/modules/cache/mod_cache.c
index 4f2d3e04..06bdf460 100644
--- a/modules/cache/mod_cache.c
+++ b/modules/cache/mod_cache.c
@@ -34,6 +34,7 @@ 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;
+static ap_filter_rec_t *cache_invalidate_filter_handle;
/*
* CACHE handler
@@ -75,11 +76,6 @@ static int cache_quick_handler(request_rec *r, int lookup)
ap_filter_rec_t *cache_out_handle;
cache_server_conf *conf;
- /* 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);
@@ -106,6 +102,9 @@ static int cache_quick_handler(request_rec *r, int lookup)
/*
* Are we allowed to serve cached info at all?
*/
+ if (!ap_cache_check_no_store(cache, r)) {
+ return DECLINED;
+ }
/* find certain cache controlling headers */
auth = apr_table_get(r->headers_in, "Authorization");
@@ -117,6 +116,40 @@ static int cache_quick_handler(request_rec *r, int lookup)
return DECLINED;
}
+ /* Are we PUT/POST/DELETE? If so, prepare to invalidate the cached entities.
+ */
+ switch (r->method_number) {
+ case M_PUT:
+ case M_POST:
+ case M_DELETE:
+ {
+
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(02461)
+ "PUT/POST/DELETE: Adding CACHE_INVALIDATE filter for %s",
+ r->uri);
+
+ /* Add cache_invalidate filter to this request to force a
+ * cache entry to be invalidated if the response is
+ * ultimately successful (2xx).
+ */
+ ap_add_output_filter_handle(
+ cache_invalidate_filter_handle, cache, r,
+ r->connection);
+
+ return DECLINED;
+ }
+ case M_GET: {
+ break;
+ }
+ default : {
+
+ ap_log_rerror(
+ APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(02462) "cache: Method '%s' not cacheable by mod_cache, ignoring: %s", r->method, r->uri);
+
+ return DECLINED;
+ }
+ }
+
/*
* Try to serve this request from the cache.
*
@@ -176,9 +209,10 @@ static int cache_quick_handler(request_rec *r, int lookup)
* is available later during running the filter may be
* different due to an internal redirect.
*/
- cache->remove_url_filter =
- ap_add_output_filter_handle(cache_remove_url_filter_handle,
- cache, r, r->connection);
+ cache->remove_url_filter = ap_add_output_filter_handle(
+ cache_remove_url_filter_handle, cache, r,
+ r->connection);
+
}
else {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv,
@@ -347,11 +381,6 @@ static int cache_handler(request_rec *r)
ap_filter_rec_t *cache_save_handle;
cache_server_conf *conf;
- /* 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);
@@ -376,6 +405,47 @@ static int cache_handler(request_rec *r)
cache->providers = providers;
/*
+ * Are we allowed to serve cached info at all?
+ */
+ if (!ap_cache_check_no_store(cache, r)) {
+ return DECLINED;
+ }
+
+ /* Are we PUT/POST/DELETE? If so, prepare to invalidate the cached entities.
+ */
+ switch (r->method_number) {
+ case M_PUT:
+ case M_POST:
+ case M_DELETE:
+ {
+
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(02463)
+ "PUT/POST/DELETE: Adding CACHE_INVALIDATE filter for %s",
+ r->uri);
+
+ /* Add cache_invalidate filter to this request to force a
+ * cache entry to be invalidated if the response is
+ * ultimately successful (2xx).
+ */
+ ap_add_output_filter_handle(
+ cache_invalidate_filter_handle, cache, r,
+ r->connection);
+
+ return DECLINED;
+ }
+ case M_GET: {
+ break;
+ }
+ default : {
+
+ ap_log_rerror(
+ APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(02464) "cache: Method '%s' not cacheable by mod_cache, ignoring: %s", r->method, r->uri);
+
+ return DECLINED;
+ }
+ }
+
+ /*
* Try to serve this request from the cache.
*
* If no existing cache file (DECLINED)
@@ -455,9 +525,10 @@ static int cache_handler(request_rec *r)
* is available later during running the filter may be
* different due to an internal redirect.
*/
- cache->remove_url_filter =
- ap_add_output_filter_handle(cache_remove_url_filter_handle,
- cache, r, r->connection);
+ cache->remove_url_filter
+ = ap_add_output_filter_handle(
+ cache_remove_url_filter_handle, cache, r,
+ r->connection);
}
else {
@@ -665,7 +736,7 @@ static int cache_save_store(ap_filter_t *f, apr_bucket_brigade *in,
*/
ap_log_rerror(APLOG_MARK, APLOG_WARNING, rv, f->r, APLOGNO(00766)
"cache: Cache provider's store_body returned an "
- "empty brigade, but didn't consume all of the"
+ "empty brigade, but didn't consume all of the "
"input brigade, standing down to prevent a spin");
ap_remove_output_filter(f);
@@ -682,6 +753,22 @@ static int cache_save_store(ap_filter_t *f, apr_bucket_brigade *in,
return rv;
}
+/**
+ * Sanity check for 304 Not Modified responses, as per RFC2616 Section 10.3.5.
+ */
+static const char *cache_header_cmp(apr_pool_t *pool, apr_table_t *left,
+ apr_table_t *right, const char *key)
+{
+ const char *h1, *h2;
+
+ if ((h1 = cache_table_getm(pool, left, key))
+ && (h2 = cache_table_getm(pool, right, key)) && (strcmp(h1, h2))) {
+ return apr_pstrcat(pool, "contradiction: 304 Not Modified, but ", key,
+ " modified", NULL);
+ }
+ return NULL;
+}
+
/*
* CACHE_SAVE filter
* ---------------
@@ -715,7 +802,7 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
apr_time_t exp, date, lastmod, now;
apr_off_t size = -1;
cache_info *info = NULL;
- char *reason;
+ const char *reason;
apr_pool_t *p;
apr_bucket *e;
apr_table_t *headers;
@@ -857,12 +944,12 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
if (etag == NULL) {
etag = apr_table_get(r->headers_out, "Etag");
}
- cc_out = apr_table_get(r->err_headers_out, "Cache-Control");
- pragma = apr_table_get(r->err_headers_out, "Pragma");
+ cc_out = cache_table_getm(r->pool, r->err_headers_out, "Cache-Control");
+ pragma = cache_table_getm(r->pool, r->err_headers_out, "Pragma");
headers = r->err_headers_out;
if (!cc_out && !pragma) {
- cc_out = apr_table_get(r->headers_out, "Cache-Control");
- pragma = apr_table_get(r->headers_out, "Pragma");
+ cc_out = cache_table_getm(r->pool, r->headers_out, "Cache-Control");
+ pragma = cache_table_getm(r->pool, r->headers_out, "Pragma");
headers = r->headers_out;
}
@@ -871,8 +958,10 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
*/
if (r->status == HTTP_NOT_MODIFIED && cache->stale_handle && !cc_out
&& !pragma) {
- cc_out = apr_table_get(cache->stale_handle->resp_hdrs, "Cache-Control");
- pragma = apr_table_get(cache->stale_handle->resp_hdrs, "Pragma");
+ cc_out = cache_table_getm(r->pool, cache->stale_handle->resp_hdrs,
+ "Cache-Control");
+ pragma = cache_table_getm(r->pool, cache->stale_handle->resp_hdrs,
+ "Pragma");
}
/* Parse the cache control header */
@@ -1000,78 +1089,117 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
/* or we've been asked not to cache it above */
reason = "r->no_cache present";
}
+ else if (cache->stale_handle
+ && APR_DATE_BAD
+ != (date = apr_date_parse_http(
+ apr_table_get(r->headers_out, "Date")))
+ && date < cache->stale_handle->cache_obj->info.date) {
- /* Hold the phone. Some servers might allow us to cache a 2xx, but
- * then make their 304 responses non cacheable. This leaves us in a
- * sticky position. If the 304 is in answer to our own conditional
- * request, we cannot send this 304 back to the client because the
- * client isn't expecting it. Instead, our only option is to respect
- * the answer to the question we asked (has it changed, answer was
- * no) and return the cached item to the client, and then respect
- * the uncacheable nature of this 304 by allowing the remove_url
- * filter to kick in and remove the cached entity.
- */
- if (reason && r->status == HTTP_NOT_MODIFIED &&
- cache->stale_handle) {
- apr_bucket_brigade *bb;
- apr_bucket *bkt;
- int status;
-
- cache->handle = cache->stale_handle;
- info = &cache->handle->cache_obj->info;
-
- /* Load in the saved status and clear the status line. */
- r->status = info->status;
- r->status_line = NULL;
-
- bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
+ /**
+ * 13.12 Cache Replacement:
+ *
+ * Note: a new response that has an older Date header value than
+ * existing cached responses is not cacheable.
+ */
+ reason = "updated entity is older than cached entity";
- r->headers_in = cache->stale_headers;
- status = ap_meets_conditions(r);
- if (status != OK) {
- r->status = status;
+ /* while this response is not cacheable, the previous response still is */
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00770)
+ "cache: Removing CACHE_REMOVE_URL filter.");
+ ap_remove_output_filter(cache->remove_url_filter);
+ }
+ else if (r->status == HTTP_NOT_MODIFIED && cache->stale_handle) {
+ apr_table_t *left = cache->stale_handle->resp_hdrs;
+ apr_table_t *right = r->headers_out;
- bkt = apr_bucket_flush_create(bb->bucket_alloc);
- APR_BRIGADE_INSERT_TAIL(bb, bkt);
+ /* and lastly, contradiction checks for revalidated responses
+ * as per RFC2616 Section 10.3.5
+ */
+ if (((reason = cache_header_cmp(r->pool, left, right, "Allow")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Content-Encoding")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Content-Language")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Content-Length")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Content-Location")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Content-MD5")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Content-Range")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Content-Type")))
+ || ((reason = cache_header_cmp(r->pool, left, right, "Expires")))
+ || ((reason = cache_header_cmp(r->pool, left, right, "ETag")))
+ || ((reason = cache_header_cmp(r->pool, left, right,
+ "Last-Modified")))) {
+ /* contradiction: 304 Not Modified, but entity header modified */
}
- else {
- /* 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 = ap_cache_cacheable_headers_out(r);
-
- /* Merge in our cached headers. However, keep any updated values. */
- cache_accept_headers(cache->handle, r, 1);
+ }
- cache->provider->recall_body(cache->handle, r->pool, bb);
+ /**
+ * Enforce RFC2616 Section 10.3.5, just in case. We caught any
+ * inconsistencies above.
+ *
+ * If the conditional GET used a strong cache validator (see section
+ * 13.3.3), the response SHOULD NOT include other entity-headers.
+ * Otherwise (i.e., the conditional GET used a weak validator), the
+ * response MUST NOT include other entity-headers; this prevents
+ * inconsistencies between cached entity-bodies and updated headers.
+ */
+ if (r->status == HTTP_NOT_MODIFIED) {
+ apr_table_unset(r->headers_out, "Allow");
+ apr_table_unset(r->headers_out, "Content-Encoding");
+ apr_table_unset(r->headers_out, "Content-Language");
+ apr_table_unset(r->headers_out, "Content-Length");
+ apr_table_unset(r->headers_out, "Content-MD5");
+ apr_table_unset(r->headers_out, "Content-Range");
+ apr_table_unset(r->headers_out, "Content-Type");
+ apr_table_unset(r->headers_out, "Last-Modified");
+ }
- bkt = apr_bucket_eos_create(bb->bucket_alloc);
- APR_BRIGADE_INSERT_TAIL(bb, bkt);
- }
+ /* Hold the phone. Some servers might allow us to cache a 2xx, but
+ * then make their 304 responses non cacheable. RFC2616 says this:
+ *
+ * If a 304 response indicates an entity not currently cached, then
+ * the cache MUST disregard the response and repeat the request
+ * without the conditional.
+ *
+ * A 304 response with contradictory headers is technically a
+ * different entity, to be safe, we remove the entity from the cache.
+ */
+ if (reason && r->status == HTTP_NOT_MODIFIED && cache->stale_handle) {
- cache->block_response = 1;
+ ap_log_rerror(
+ APLOG_MARK, APLOG_INFO, 0, r, APLOGNO() "cache: %s responded with an uncacheable 304, retrying the request. Reason: %s", r->unparsed_uri, reason);
- /* we've got a cache conditional hit! tell anyone who cares */
- cache_run_cache_status(
- cache->handle,
- r,
- r->headers_out,
- AP_CACHE_REVALIDATE,
- apr_psprintf(
- r->pool,
- "conditional cache hit: 304 was uncacheable though (%s); entity removed",
+ /* we've got a cache conditional miss! tell anyone who cares */
+ cache_run_cache_status(cache->handle, r, r->headers_out, AP_CACHE_MISS,
+ apr_psprintf(r->pool,
+ "conditional cache miss: 304 was uncacheable, entity removed: %s",
reason));
+ /* remove the cached entity immediately, we might cache it again */
+ ap_remove_output_filter(cache->remove_url_filter);
+ cache_remove_url(cache, r);
+
/* let someone else attempt to cache */
cache_remove_lock(conf, cache, r, NULL);
- return ap_pass_brigade(f->next, bb);
+ /* remove this filter from the chain */
+ ap_remove_output_filter(f);
+
+ /* retry without the conditionals */
+ apr_table_unset(r->headers_in, "If-Match");
+ apr_table_unset(r->headers_in, "If-Modified-Since");
+ apr_table_unset(r->headers_in, "If-None-Match");
+ apr_table_unset(r->headers_in, "If-Range");
+ apr_table_unset(r->headers_in, "If-Unmodified-Since");
+
+ ap_internal_redirect(r->uri, r);
+
+ return APR_SUCCESS;
}
if (reason) {
@@ -1186,7 +1314,7 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
if (rv != OK) {
/* we've got a cache miss! tell anyone who cares */
cache_run_cache_status(cache->handle, r, r->headers_out, AP_CACHE_MISS,
- "cache miss: create_entity failed");
+ "cache miss: cache unwilling to store response");
/* Caching layer declined the opportunity to cache the response */
ap_remove_output_filter(f);
@@ -1303,9 +1431,6 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
/* 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
@@ -1319,7 +1444,9 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
r->headers_out = ap_cache_cacheable_headers_out(r);
/* Merge in our cached headers. However, keep any updated values. */
- cache_accept_headers(cache->handle, r, 1);
+ /* take output, overlay on top of cached */
+ cache_accept_headers(cache->handle, r, r->headers_out,
+ cache->handle->resp_hdrs, 1);
}
/* Write away header information to cache. It is possible that we are
@@ -1342,6 +1469,10 @@ static apr_status_t cache_save_filter(ap_filter_t *f, apr_bucket_brigade *in)
apr_bucket *bkt;
int status;
+ /* Load in the saved status and clear the status line. */
+ r->status = info->status;
+ r->status_line = NULL;
+
/* We're just saving response headers, so we are done. Commit
* the response at this point, unless there was a previous error.
*/
@@ -1483,6 +1614,70 @@ static apr_status_t cache_remove_url_filter(ap_filter_t *f,
}
/*
+ * CACHE_INVALIDATE filter
+ * -----------------------
+ *
+ * This filter gets added in the quick handler should a PUT, POST or DELETE
+ * method be detected. If the response is successful, we must invalidate any
+ * cached entity as per RFC2616 section 13.10.
+ *
+ * CACHE_INVALIDATE 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
+ * from the chain.
+ *
+ * CACHE_INVALIDATE 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.
+ */
+static apr_status_t cache_invalidate_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_INVALIDATE manually; they should really
+ * use mod_cache configuration to do that. So:
+ * 1. Remove ourselves
+ * 2. Do nothing and bail out
+ */
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02465)
+ "cache: CACHE_INVALIDATE enabled unexpectedly: %s", r->uri);
+ }
+ else {
+
+ if (r->status > 299) {
+
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02466)
+ "cache: response status to '%s' method is %d (>299), not invalidating cached entity: %s", r->method, r->status, r->uri);
+
+ }
+ else {
+
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, APR_SUCCESS, r, APLOGNO(02467)
+ "cache: Invalidating all cached entities in response to '%s' request for %s",
+ r->method, r->uri);
+
+ cache_invalidate(cache, r);
+
+ /* we've got a cache invalidate! tell everyone who cares */
+ cache_run_cache_status(cache->handle, r, r->headers_out,
+ AP_CACHE_INVALIDATE, apr_psprintf(r->pool,
+ "cache invalidated by %s", r->method));
+
+ }
+
+ }
+
+ /* remove ourselves */
+ ap_remove_output_filter(f);
+ return ap_pass_brigade(f->next, in);
+}
+
+/*
* CACHE filter
* ------------
*
@@ -1579,11 +1774,11 @@ static int cache_status(cache_handle_t *h, request_rec *r,
x_cache = conf->x_cache;
}
if (x_cache) {
- apr_table_setn(headers, "X-Cache",
- apr_psprintf(r->pool, "%s from %s",
- status == AP_CACHE_HIT ? "HIT" : status
- == AP_CACHE_REVALIDATE ? "REVALIDATE" : "MISS",
- r->server->server_hostname));
+ apr_table_setn(headers, "X-Cache", apr_psprintf(r->pool, "%s from %s",
+ status == AP_CACHE_HIT ? "HIT"
+ : status == AP_CACHE_REVALIDATE ? "REVALIDATE" : status
+ == AP_CACHE_INVALIDATE ? "INVALIDATE" : "MISS",
+ r->server->server_hostname));
}
if (dconf && dconf->x_cache_detail_set) {
@@ -1640,7 +1835,8 @@ static void cache_insert_error_filter(request_rec *r)
if (cache->stale_handle && cache->save_filter
&& !cache->stale_handle->cache_obj->info.control.must_revalidate
- && !cache->stale_handle->cache_obj->info.control.proxy_revalidate) {
+ && !cache->stale_handle->cache_obj->info.control.proxy_revalidate
+ && !cache->stale_handle->cache_obj->info.control.s_maxage) {
const char *warn_head;
cache_server_conf
*conf =
@@ -1773,7 +1969,7 @@ static void *merge_dir_config(apr_pool_t *p, void *basev, void *addv) {
static void * create_cache_config(apr_pool_t *p, server_rec *s)
{
- const char *tmppath;
+ const char *tmppath = NULL;
cache_server_conf *ps = apr_pcalloc(p, sizeof(cache_server_conf));
/* array of URL prefixes for which caching is enabled */
@@ -2068,7 +2264,7 @@ static const char *add_cache_disable(cmd_parms *parms, void *dummy,
&cache_module);
if (parms->path) {
- if (!strcmp(url, "on")) {
+ if (!strcasecmp(url, "on")) {
dconf->disable = 1;
dconf->disable_set = 1;
return NULL;
@@ -2454,6 +2650,11 @@ static void register_hooks(apr_pool_t *p)
cache_remove_url_filter,
NULL,
AP_FTYPE_PROTOCOL);
+ cache_invalidate_filter_handle =
+ ap_register_output_filter("CACHE_INVALIDATE",
+ cache_invalidate_filter,
+ NULL,
+ AP_FTYPE_PROTOCOL);
ap_hook_post_config(cache_post_config, NULL, NULL, APR_HOOK_REALLY_FIRST);
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-03-02 14:58:33 +0000