From 9bc1917a27a2323e535aadb081e38172ae0e3fc2 Mon Sep 17 00:00:00 2001
From: Stefan Eissing <icing@apache.org>
Date: Mon, 18 Mar 2019 08:49:59 +0000
Subject: [PATCH] Merge of r1855705 from trunk:

core: merge consecutive slashes in the path



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1855737 13f79535-47bb-0310-9956-ffa450edef68
---
 include/http_core.h      |  2 +-
 include/httpd.h          | 14 ++++++++++++--
 server/core.c            | 13 +++++++++++++
 server/request.c         | 25 +++++++++----------------
 server/util.c            | 10 +++++++---
 5 files changed, 43 insertions(+), 21 deletions(-)

diff --git a/include/http_core.h b/include/http_core.h
index 35df5dc9601..8e109882244 100644
--- a/include/http_core.h
+++ b/include/http_core.h
@@ -740,7 +740,7 @@ typedef struct {
 #define AP_HTTP_METHODS_LENIENT       1
 #define AP_HTTP_METHODS_REGISTERED    2
     char http_methods;
-
+    unsigned int merge_slashes;
 } core_server_config;
 
 /* for AddOutputFiltersByType in core.c */
diff --git a/include/httpd.h b/include/httpd.h
index 65392f83546..99f7f041aea 100644
--- a/include/httpd.h
+++ b/include/httpd.h
@@ -1697,11 +1697,21 @@ AP_DECLARE(int) ap_unescape_url_keep2f(char *url, int decode_slashes);
 AP_DECLARE(int) ap_unescape_urlencoded(char *query);
 
 /**
- * Convert all double slashes to single slashes
- * @param name The string to convert
+ * Convert all double slashes to single slashes, except where significant
+ * to the filesystem on the current platform.
+ * @param name The string to convert, assumed to be a filesystem path
  */
 AP_DECLARE(void) ap_no2slash(char *name);
 
+/**
+ * Convert all double slashes to single slashes, except where significant
+ * to the filesystem on the current platform.
+ * @param name The string to convert
+ * @param is_fs_path if set to 0, the significance of any double-slashes is 
+ *        ignored.
+ */
+AP_DECLARE(void) ap_no2slash_ex(char *name, int is_fs_path);
+
 /**
  * Remove all ./ and xx/../ substrings from a file name. Also remove
  * any leading ../ or /../ substrings.
diff --git a/server/core.c b/server/core.c
index e2a91c7a0c6..eacb54fecec 100644
--- a/server/core.c
+++ b/server/core.c
@@ -490,6 +490,7 @@ static void *create_core_server_config(apr_pool_t *a, server_rec *s)
 
     conf->protocols = apr_array_make(a, 5, sizeof(const char *));
     conf->protocols_honor_order = -1;
+    conf->merge_slashes = AP_CORE_CONFIG_UNSET; 
     
     return (void *)conf;
 }
@@ -555,6 +556,7 @@ static void *merge_core_server_configs(apr_pool_t *p, void *basev, void *virtv)
     conf->protocols_honor_order = ((virt->protocols_honor_order < 0)?
                                        base->protocols_honor_order :
                                        virt->protocols_honor_order);
+    AP_CORE_MERGE_FLAG(merge_slashes, conf, base, virt);
     
     return conf;
 }
@@ -1863,6 +1865,13 @@ static const char *set_qualify_redirect_url(cmd_parms *cmd, void *d_, int flag)
     return NULL;
 }
 
+static const char *set_core_server_flag(cmd_parms *cmd, void *s_, int flag)
+{
+    core_server_config *conf =
+        ap_get_core_module_config(cmd->server->module_config);
+    return ap_set_flag_slot(cmd, conf, flag);
+}
+
 static const char *set_override_list(cmd_parms *cmd, void *d_, int argc, char *const argv[])
 {
     core_dir_config *d = d_;
@@ -4562,6 +4571,10 @@ AP_INIT_ITERATE("HttpProtocolOptions", set_http_protocol_options, NULL, RSRC_CON
                 "'Unsafe' or 'Strict' (default). Sets HTTP acceptance rules"),
 AP_INIT_ITERATE("RegisterHttpMethod", set_http_method, NULL, RSRC_CONF,
                 "Registers non-standard HTTP methods"),
+AP_INIT_FLAG("MergeSlashes", set_core_server_flag, 
+             (void *)APR_OFFSETOF(core_server_config, merge_slashes),  
+             RSRC_CONF,
+             "Controls whether consecutive slashes in the URI path are merged"),
 { NULL }
 };
 
diff --git a/server/request.c b/server/request.c
index dbe3e07f150..1ce8908824b 100644
--- a/server/request.c
+++ b/server/request.c
@@ -167,6 +167,8 @@ AP_DECLARE(int) ap_process_request_internal(request_rec *r)
     int file_req = (r->main && r->filename);
     int access_status;
     core_dir_config *d;
+    core_server_config *sconf =
+        ap_get_core_module_config(r->server->module_config);
 
     /* Ignore embedded %2F's in path for proxy requests */
     if (!r->proxyreq && r->parsed_uri.path) {
@@ -191,6 +193,10 @@ AP_DECLARE(int) ap_process_request_internal(request_rec *r)
     }
 
     ap_getparents(r->uri);     /* OK --- shrinking transformations... */
+    if (sconf->merge_slashes != AP_CORE_CONFIG_OFF) { 
+        ap_no2slash(r->uri);
+        ap_no2slash(r->parsed_uri.path);
+     }
 
     /* All file subrequests are a huge pain... they cannot bubble through the
      * next several steps.  Only file subrequests are allowed an empty uri,
@@ -1411,20 +1417,7 @@ AP_DECLARE(int) ap_location_walk(request_rec *r)
 
     cache = prep_walk_cache(AP_NOTE_LOCATION_WALK, r);
     cached = (cache->cached != NULL);
-
-    /* Location and LocationMatch differ on their behaviour w.r.t. multiple
-     * slashes.  Location matches multiple slashes with a single slash,
-     * LocationMatch doesn't.  An exception, for backwards brokenness is
-     * absoluteURIs... in which case neither match multiple slashes.
-     */
-    if (r->uri[0] != '/') {
-        entry_uri = r->uri;
-    }
-    else {
-        char *uri = apr_pstrdup(r->pool, r->uri);
-        ap_no2slash(uri);
-        entry_uri = uri;
-    }
+    entry_uri = r->uri;
 
     /* If we have an cache->cached location that matches r->uri,
      * and the vhost's list of locations hasn't changed, we can skip
@@ -1491,7 +1484,7 @@ AP_DECLARE(int) ap_location_walk(request_rec *r)
                     pmatch = apr_palloc(rxpool, nmatch*sizeof(ap_regmatch_t));
                 }
 
-                if (ap_regexec(entry_core->r, r->uri, nmatch, pmatch, 0)) {
+                if (ap_regexec(entry_core->r, entry_uri, nmatch, pmatch, 0)) {
                     continue;
                 }
 
@@ -1501,7 +1494,7 @@ AP_DECLARE(int) ap_location_walk(request_rec *r)
                         apr_table_setn(r->subprocess_env,
                                        ((const char **)entry_core->refs->elts)[i],
                                        apr_pstrndup(r->pool,
-                                       r->uri + pmatch[i].rm_so,
+                                       entry_uri + pmatch[i].rm_so,
                                        pmatch[i].rm_eo - pmatch[i].rm_so));
                     }
                 }
diff --git a/server/util.c b/server/util.c
index fd7a0a14763..607c4850d86 100644
--- a/server/util.c
+++ b/server/util.c
@@ -561,16 +561,16 @@ AP_DECLARE(void) ap_getparents(char *name)
         name[l] = '\0';
     }
 }
-
-AP_DECLARE(void) ap_no2slash(char *name)
+AP_DECLARE(void) ap_no2slash_ex(char *name, int is_fs_path)
 {
+
     char *d, *s;
 
     s = d = name;
 
 #ifdef HAVE_UNC_PATHS
     /* Check for UNC names.  Leave leading two slashes. */
-    if (s[0] == '/' && s[1] == '/')
+    if (is_fs_path && s[0] == '/' && s[1] == '/')
         *d++ = *s++;
 #endif
 
@@ -587,6 +587,10 @@ AP_DECLARE(void) ap_no2slash(char *name)
     *d = '\0';
 }
 
+AP_DECLARE(void) ap_no2slash(char *name)
+{
+    ap_no2slash_ex(name, 1);
+}
 
 /*
  * copy at most n leading directories of s into d
