core: Add expression support to ErrorDocument. Switch from a fixed

sized 664 byte array per merge to a hash table.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1661448 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/CHANGES b/CHANGES
index 845244242804509da4e6fca5c8ae2f70b851c58d..d379baa03530c1944d6b2d13675bdb1b25e14b72 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -6,6 +6,9 @@ Changes with Apache 2.5.0
      calls r:wsupgrade() can cause a child process crash. 
      [Edward Lu <Chaosed0 gmail.com>]
 
+  *) core: Add expression support to ErrorDocument. Switch from a fixed
+     sized 664 byte array per merge to a hash table. [Graham Leggett]
+
   *) mod_ssl: Add the SSL_CLIENT_CERT_RFC4523_CEA variable, which provides
      a combination of certificate serialNumber and issuer as defined by
      CertificateExactMatch in RFC4523. [Graham Leggett]

diff --git a/docs/log-message-tags/next-number b/docs/log-message-tags/next-number
index e069f01702615b9dea7ccc69be344f7228a35c3d..55d9622930bed0dfdd41147458c8876ac1b4c48f 100644 (file)
--- a/docs/log-message-tags/next-number
+++ b/docs/log-message-tags/next-number
@@ -1 +1 @@
-2830
+2831

diff --git a/docs/manual/expr.xml b/docs/manual/expr.xml
index 44e35eaee90532fb86903f4b9a03a05eed65fa89..dc6a5052952ae0d4fc7ca78f0c8eb0b54eff7b7d 100644 (file)
--- a/docs/manual/expr.xml
+++ b/docs/manual/expr.xml
@@ -40,6 +40,7 @@
 <seealso><directive module="core" type="section">If</directive></seealso>
 <seealso><directive module="core" type="section">ElseIf</directive></seealso>
 <seealso><directive module="core" type="section">Else</directive></seealso>
+<seealso><directive module="core" type="section">ErrorDocument</directive></seealso>
 <seealso><directive module="mod_alias">Alias</directive></seealso>
 <seealso><directive module="mod_alias">ScriptAlias</directive></seealso>
 <seealso><directive module="mod_alias">Redirect</directive></seealso>

diff --git a/docs/manual/mod/core.xml b/docs/manual/mod/core.xml
index 19c1e3aade9a42665f65d0139af60c606c444444..0f6351ee9c61ae51df23fb82402db63de6072825 100644 (file)
--- a/docs/manual/mod/core.xml
+++ b/docs/manual/mod/core.xml
@@ -1254,10 +1254,15 @@ in case of an error</description>
     or a message. Apache httpd will sometimes offer additional information
     regarding the problem/error.</p>
 
+    <p>From 2.4.13, <a href="../expr.html">expression syntax</a> can be
+    used inside the directive to produce dynamic strings and URLs.</p>
+
     <p>URLs can begin with a slash (/) for local web-paths (relative
     to the <directive module="core">DocumentRoot</directive>), or be a
     full URL which the client can resolve. Alternatively, a message
-    can be provided to be displayed by the browser. Examples:</p>
+    can be provided to be displayed by the browser. Note that deciding
+    whether the parameter is an URL, a path or a message is performed
+    before any expression is parsed. Examples:</p>
 
     <highlight language="config">
 ErrorDocument 500 http://foo.example.com/cgi-bin/tester
@@ -1265,6 +1270,7 @@ ErrorDocument 404 /cgi-bin/bad_urls.pl
 ErrorDocument 401 /subscription_info.html
 ErrorDocument 403 "Sorry can't allow you access today"
 ErrorDocument 403 Forbidden!
+ErrorDocument 403 /cgi-bin/forbidden.pl?referrer=%{escape:%{HTTP_REFERER}}
     </highlight>
 
     <p>Additionally, the special value <code>default</code> can be used

diff --git a/include/ap_mmn.h b/include/ap_mmn.h
index c6790aba7128c0047a106ec9c17407836790adff..f92e106d3b7c114d9420b08c14fb4c817832c299 100644 (file)
--- a/include/ap_mmn.h
+++ b/include/ap_mmn.h
@@ -478,6 +478,7 @@
  * 20140627.10 (2.5.0-dev) Add ap_proxy_de_socketfy to mod_proxy.h
  * 20150121.0 (2.5.0-dev)  Revert field addition from core_dir_config; r1653666
  * 20150121.1 (2.5.0-dev)  Add cmd_parms_struct.parent to http_config.h
+ * 20150121.2 (2.5.0-dev)  Add response_code_exprs to http_core.h
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503235UL /* "AP25" */
@@ -485,7 +486,7 @@
 #ifndef MODULE_MAGIC_NUMBER_MAJOR
 #define MODULE_MAGIC_NUMBER_MAJOR 20150121
 #endif
-#define MODULE_MAGIC_NUMBER_MINOR 1                 /* 0...n */
+#define MODULE_MAGIC_NUMBER_MINOR 2                 /* 0...n */
 
 /**
  * Determine if the server's current MODULE_MAGIC_NUMBER is at least a

diff --git a/include/http_core.h b/include/http_core.h
index 33430880cb75acf4c354504f48bed20b7f55154f..87481268c197dac99353da17defe7622a2fb720e 100644 (file)
--- a/include/http_core.h
+++ b/include/http_core.h
@@ -497,12 +497,7 @@ typedef struct {
     overrides_t override;
     allow_options_t override_opts;
 
-    /* Custom response config. These can contain text or a URL to redirect to.
-     * if response_code_strings is NULL then there are none in the config,
-     * if it's not null then it's allocated to sizeof(char*)*RESPONSE_CODES.
-     * This lets us do quick merges in merge_core_dir_configs().
-     */
-
+    /* Used to be the custom response config. No longer used. */
     char **response_code_strings; /* from ErrorDocument, not from
                                    * ap_custom_response() */
 
@@ -632,6 +627,13 @@ typedef struct {
      * advice
      */
     unsigned int cgi_pass_auth : 2;
+
+    /** Custom response config with expression support. The hash table
+     * contains compiled expressions keyed against the custom response
+     * code.
+     */
+    apr_hash_t *response_code_exprs;
+
 } core_dir_config;
 
 /* macro to implement off by default behaviour */

diff --git a/server/core.c b/server/core.c
index 587e3751fbd020dca13ef2399d4db989c3a8f1a6..44187631c8a6357173d7a879953ef263416ed9b8 100644 (file)
--- a/server/core.c
+++ b/server/core.c
@@ -260,23 +260,14 @@ static void *merge_core_dir_configs(apr_pool_t *a, void *basev, void *newv)
         conf->override_list = new->override_list;
     }
 
-    if (conf->response_code_strings == NULL) {
-        conf->response_code_strings = new->response_code_strings;
+    if (conf->response_code_exprs == NULL) {
+        conf->response_code_exprs = new->response_code_exprs;
     }
-    else if (new->response_code_strings != NULL) {
-        /* If we merge, the merge-result must have its own array
-         */
-        conf->response_code_strings = apr_pmemdup(a,
-            base->response_code_strings,
-            sizeof(*conf->response_code_strings) * RESPONSE_CODES);
-
-        for (i = 0; i < RESPONSE_CODES; ++i) {
-            if (new->response_code_strings[i] != NULL) {
-                conf->response_code_strings[i] = new->response_code_strings[i];
-            }
-        }
+    else if (new->response_code_exprs != NULL) {
+        conf->response_code_exprs = apr_hash_overlay(a,
+                new->response_code_exprs, conf->response_code_exprs);
     }
-    /* Otherwise we simply use the base->response_code_strings array
+    /* Otherwise we simply use the base->response_code_exprs array
      */
 
     if (new->hostname_lookups != HOSTNAME_LOOKUP_UNSET) {
@@ -833,25 +824,46 @@ char *ap_response_code_string(request_rec *r, int error_index)
 {
     core_dir_config *dirconf;
     core_request_config *reqconf = ap_get_core_module_config(r->request_config);
+    const char *err;
+    const char *response;
+    void *val;
+    ap_expr_info_t *expr;
 
     /* check for string registered via ap_custom_response() first */
-    if (reqconf->response_code_strings != NULL &&
-        reqconf->response_code_strings[error_index] != NULL) {
+    if (reqconf->response_code_strings != NULL
+            && reqconf->response_code_strings[error_index] != NULL) {
         return reqconf->response_code_strings[error_index];
     }
 
     /* check for string specified via ErrorDocument */
     dirconf = ap_get_core_module_config(r->per_dir_config);
 
-    if (dirconf->response_code_strings == NULL) {
+    if (!dirconf->response_code_exprs) {
+        return NULL;
+    }
+
+    expr = apr_hash_get(dirconf->response_code_exprs, &error_index,
+            sizeof(error_index));
+    if (!expr) {
         return NULL;
     }
 
-    if (dirconf->response_code_strings[error_index] == &errordocument_default) {
+    /* special token to indicate revert back to default */
+    if ((char *) expr == &errordocument_default) {
         return NULL;
     }
 
-    return dirconf->response_code_strings[error_index];
+    err = NULL;
+    response = ap_expr_str_exec(r, expr, &err);
+    if (err) {
+        ap_log_rerror(
+                APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02830) "core: ErrorDocument: can't "
+                "evaluate require expression: %s", err);
+        return NULL;
+    }
+
+    /* alas, duplication required as we return not-const */
+    return apr_pstrdup(r->pool, response);
 }
 
 
@@ -1566,27 +1578,43 @@ static const char *set_error_document(cmd_parms *cmd, void *conf_,
                      "directive --- ignoring!", cmd->directive->filename, cmd->directive->line_num);
     }
     else { /* Store it... */
-        if (conf->response_code_strings == NULL) {
-            conf->response_code_strings =
-                apr_pcalloc(cmd->pool,
-                            sizeof(*conf->response_code_strings) *
-                            RESPONSE_CODES);
+        if (conf->response_code_exprs == NULL) {
+            conf->response_code_exprs = apr_hash_make(cmd->pool);
         }
 
         if (strcasecmp(msg, "default") == 0) {
             /* special case: ErrorDocument 404 default restores the
              * canned server error response
              */
-            conf->response_code_strings[index_number] = &errordocument_default;
+            apr_hash_set(conf->response_code_exprs,
+                    apr_pmemdup(cmd->pool, &index_number, sizeof(index_number)),
+                    sizeof(index_number), &errordocument_default);
         }
         else {
+            ap_expr_info_t *expr;
+            const char *expr_err = NULL;
+
             /* hack. Prefix a " if it is a msg; as that is what
              * http_protocol.c relies on to distinguish between
              * a msg and a (local) path.
              */
-            conf->response_code_strings[index_number] = (what == MSG) ?
-                    apr_pstrcat(cmd->pool, "\"", msg, NULL) :
-                    apr_pstrdup(cmd->pool, msg);
+            const char *response =
+                    (what == MSG) ? apr_pstrcat(cmd->pool, "\"", msg, NULL) :
+                            apr_pstrdup(cmd->pool, msg);
+
+            expr = ap_expr_parse_cmd(cmd, response, AP_EXPR_FLAG_STRING_RESULT,
+                    &expr_err, NULL);
+
+            if (expr_err) {
+                return apr_pstrcat(cmd->temp_pool,
+                                   "Cannot parse expression in ErrorDocument: ",
+                                   expr_err, NULL);
+            }
+
+            apr_hash_set(conf->response_code_exprs,
+                    apr_pmemdup(cmd->pool, &index_number, sizeof(index_number)),
+                    sizeof(index_number), expr);
+
         }
     }