From: Yann Ylavic <ylavic@apache.org>
Date: Wed, 15 Dec 2021 11:35:36 +0000 (+0000)
Subject: mod_proxy: follow up to r1895921: Don't prevent forwarding URIs w/ no hostname.
X-Git-Tag: 2.5.0-alpha2-ci-test-only~642
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=15a5cde91626a68425f7f5e215f5a816dbb956f7;p=thirdparty%2Fapache%2Fhttpd.git

mod_proxy: follow up to r1895921: Don't prevent forwarding URIs w/ no hostname.

r1895921 changed proxy_detect() to disable forward proxying for URIs with no
hostname which is wrong, there might exist a third-party proxy module handling
the "urn:" scheme for instance (thanks Roy for the catch!).

For this to work, we also need to leave the forward proxied URI alone in
ap_proxy_pre_request() with no UDS special case or alike, a proxy module can
then catch (or not) the original URI as expected.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1895981 13f79535-47bb-0310-9956-ffa450edef68
---

diff --git a/modules/proxy/mod_proxy.c b/modules/proxy/mod_proxy.c
index b0dc09ecdf1..27f31185787 100644
--- a/modules/proxy/mod_proxy.c
+++ b/modules/proxy/mod_proxy.c
@@ -781,9 +781,10 @@ static int proxy_detect(request_rec *r)
 
     /* Ick... msvc (perhaps others) promotes ternary short results to int */
 
-    if (conf->req && r->parsed_uri.scheme && r->parsed_uri.hostname) {
+    if (conf->req && r->parsed_uri.scheme) {
         /* but it might be something vhosted */
-        if (ap_cstr_casecmp(r->parsed_uri.scheme, ap_http_scheme(r)) != 0
+        if (!r->parsed_uri.hostname
+            || ap_cstr_casecmp(r->parsed_uri.scheme, ap_http_scheme(r)) != 0
             || !ap_matches_request_vhost(r, r->parsed_uri.hostname,
                                          (apr_port_t)(r->parsed_uri.port_str
                                                       ? r->parsed_uri.port
diff --git a/modules/proxy/mod_proxy.h b/modules/proxy/mod_proxy.h
index f0f09947886..9ba736d01f1 100644
--- a/modules/proxy/mod_proxy.h
+++ b/modules/proxy/mod_proxy.h
@@ -768,6 +768,7 @@ PROXY_DECLARE(int) ap_proxy_worker_can_upgrade(apr_pool_t *p,
 #define AP_PROXY_WORKER_IS_PREFIX   (1u << 0)
 #define AP_PROXY_WORKER_IS_MATCH    (1u << 1)
 #define AP_PROXY_WORKER_IS_MALLOCED (1u << 2)
+#define AP_PROXY_WORKER_NO_UDS      (1u << 3)
 
 /**
  * Get the worker from proxy configuration, looking for either PREFIXED or
diff --git a/modules/proxy/proxy_util.c b/modules/proxy/proxy_util.c
index f4adfe55426..b77b92f7b8f 100644
--- a/modules/proxy/proxy_util.c
+++ b/modules/proxy/proxy_util.c
@@ -1734,9 +1734,11 @@ PROXY_DECLARE(proxy_worker *) ap_proxy_get_worker_ex(apr_pool_t *p,
         return NULL;
     }
 
-    url = ap_proxy_de_socketfy(p, url);
-    if (!url) {
-        return NULL;
+    if (!(mask & AP_PROXY_WORKER_NO_UDS)) {
+        url = ap_proxy_de_socketfy(p, url);
+        if (!url) {
+            return NULL;
+        }
     }
 
     c = ap_strchr_c(url, ':');
@@ -2319,18 +2321,20 @@ PROXY_DECLARE(int) ap_proxy_pre_request(proxy_worker **worker,
 
     access_status = proxy_run_pre_request(worker, balancer, r, conf, url);
     if (access_status == DECLINED && *balancer == NULL) {
-        *worker = ap_proxy_get_worker(r->pool, NULL, conf, *url);
+        const int forward = (r->proxyreq == PROXYREQ_PROXY);
+        *worker = ap_proxy_get_worker_ex(r->pool, NULL, conf, *url,
+                                         forward ? AP_PROXY_WORKER_NO_UDS : 0);
         if (*worker) {
             ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
                           "%s: found worker %s for %s",
                           (*worker)->s->scheme, (*worker)->s->name, *url);
             *balancer = NULL;
-            if (!fix_uds_filename(r, url)) {
+            if (!forward && !fix_uds_filename(r, url)) {
                 return HTTP_INTERNAL_SERVER_ERROR;
             }
             access_status = OK;
         }
-        else if (r->proxyreq == PROXYREQ_PROXY) {
+        else if (forward) {
             if (conf->forward) {
                 ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
                               "*: found forward proxy worker for %s", *url);