On Thu, Jan 7, 2021 at 2:19 PM <yla...@apache.org> wrote:
>
> Author: ylavic
> Date: Thu Jan 7 13:19:08 2021
> New Revision: 1885239
>
> URL: http://svn.apache.org/viewvc?rev=1885239&view=rev
> Log:
> mod_proxy_wstunnel: leave Upgrade requests handling to mod_proxy_http.
[snip]
> +static int proxy_wstunnel_post_config(apr_pool_t *pconf, apr_pool_t *plog,
> + apr_pool_t *ptemp, server_rec *s)
> +{
> + fallback_to_mod_proxy_http = 0;
> + if (ap_state_query(AP_SQ_MAIN_STATE) != AP_SQ_MS_CREATE_PRE_CONFIG) {
> + apr_size_t i = 0;
> + const module *mod;
> + while ((mod = ap_loaded_modules[i++])) {
> + if (strcmp(mod->name, "mod_proxy_http.c") == 0) {
> + fallback_to_mod_proxy_http = 1;
> + break;
> + }
> + }
> + }
I wonder if, instead of the above loop to check whether mod_proxy_http
is loaded, we'd better have an OPTIONAL_FN registered by
mod_proxy_http and retrieved here.
ISTR that we allow for different versions of (proxy) modules to run
together, so if a user upgrades to the latest mod_proxy_wstunnel but
keeps an older mod_proxy_http the above would not work..
Maybe I should apply the attached patch instead, or is it overkill?
Cheers;
Yann.
Index: include/ap_mmn.h
===================================================================
--- include/ap_mmn.h (revision 1885238)
+++ include/ap_mmn.h (working copy)
@@ -664,6 +664,7 @@
* ap_proxy_read_input().
* 20200705.4 (2.5.1-dev) Add ap_get_status_line_ex()
* 20201214.0 (2.5.1-dev) Axe struct core_net_rec
+ * 20201214.1 (2.5.1-dev) Add optional proxy_http_module_can_upgrade()
*/
#define MODULE_MAGIC_COOKIE 0x41503235UL /* "AP25" */
@@ -671,7 +672,7 @@
#ifndef MODULE_MAGIC_NUMBER_MAJOR
#define MODULE_MAGIC_NUMBER_MAJOR 20201214
#endif
-#define MODULE_MAGIC_NUMBER_MINOR 0 /* 0...n */
+#define MODULE_MAGIC_NUMBER_MINOR 1 /* 0...n */
/**
* Determine if the server's current MODULE_MAGIC_NUMBER is at least a
Index: modules/proxy/mod_proxy.h
===================================================================
--- modules/proxy/mod_proxy.h (revision 1885239)
+++ modules/proxy/mod_proxy.h (working copy)
@@ -1454,6 +1454,21 @@ PROXY_DECLARE(apr_status_t) ap_proxy_transfer_betw
apr_off_t bsize,
int flags);
+/**
+ * Whether mod_proxy_http can switch/upgrade to another protocol (tunneling).
+ * @return 1
+ * @note This optional function exists for 2.4 compatibility, should a
+ * mod_proxy_wstunnel able to fallback to proxy_http for upgrades be
+ * running with an older mod_proxy_http unable to handle it. The mere
+ * existence of the optional function is enough to determine whether
+ * mod_proxy_http handles upgrades, since the function is registered
+ * there and in the capable versions only, so there is actually no
+ * need to call the function (its return value is always true anyway),
+ * thus APR_RETRIEVE_OPTIONAL_FN(proxy_http_module_can_upgrade) != NULL
+ * is the relevant test.
+ */
+APR_DECLARE_OPTIONAL_FN(int, proxy_http_module_can_upgrade, (void));
+
extern module PROXY_DECLARE_DATA proxy_module;
#endif /*MOD_PROXY_H*/
Index: modules/proxy/mod_proxy_http.c
===================================================================
--- modules/proxy/mod_proxy_http.c (revision 1885240)
+++ modules/proxy/mod_proxy_http.c (working copy)
@@ -2160,6 +2160,11 @@ static int proxy_http_post_config(apr_pool_t *pcon
return OK;
}
+static int proxy_http_module_can_upgrade(void)
+{
+ return 1;
+}
+
static void ap_proxy_http_register_hook(apr_pool_t *p)
{
ap_hook_post_config(proxy_http_post_config, NULL, NULL, APR_HOOK_MIDDLE);
@@ -2166,6 +2171,7 @@ static void ap_proxy_http_register_hook(apr_pool_t
proxy_hook_scheme_handler(proxy_http_handler, NULL, NULL, APR_HOOK_FIRST);
proxy_hook_canon_handler(proxy_http_canon, NULL, NULL, APR_HOOK_FIRST);
warn_rx = ap_pregcomp(p, "[0-9]{3}[ \t]+[^ \t]+[ \t]+\"[^\"]*\"([ \t]+\"([^\"]+)\")?", 0);
+ APR_REGISTER_OPTIONAL_FN(proxy_http_module_can_upgrade);
}
AP_DECLARE_MODULE(proxy_http) = {
Index: modules/proxy/mod_proxy_wstunnel.c
===================================================================
--- modules/proxy/mod_proxy_wstunnel.c (revision 1885239)
+++ modules/proxy/mod_proxy_wstunnel.c (working copy)
@@ -452,17 +452,8 @@ static const char * proxyws_set_asynch_delay(cmd_p
static int proxy_wstunnel_post_config(apr_pool_t *pconf, apr_pool_t *plog,
apr_pool_t *ptemp, server_rec *s)
{
- fallback_to_mod_proxy_http = 0;
- if (ap_state_query(AP_SQ_MAIN_STATE) != AP_SQ_MS_CREATE_PRE_CONFIG) {
- apr_size_t i = 0;
- const module *mod;
- while ((mod = ap_loaded_modules[i++])) {
- if (strcmp(mod->name, "mod_proxy_http.c") == 0) {
- fallback_to_mod_proxy_http = 1;
- break;
- }
- }
- }
+ fallback_to_mod_proxy_http =
+ APR_RETRIEVE_OPTIONAL_FN(proxy_http_module_can_upgrade) != NULL;
return OK;
}
