From: Ruediger Pluem Date: Mon, 14 Oct 2024 06:56:45 +0000 Subject: When a rewrite to proxy is configured in the server config, a check is made to make sure mod_proxy is active. But the same is not done if a rewrite to proxy is configured in an .htaccess file. Basically this patch is the block of code from hook_uri2file that does the proxy check, copied to hook_fixup. Patch provided by Michael Streeter [mstreeter1 gmail.com], slightly modified to use a new APLOGNO PR 56264 mod_rewrite, mod_proxy: mod_proxy to cononicalize rewritten [P] URLs. PR 69235. When mod_rewrite sets a "proxy:" URL with [P], it should be canonicalized by mod_proxy still, notably to handle any "unix:" local socket part. To avoid double encoding in perdir context, a follow up commit should remove the ap_escape_uri() done in mod_rewrite since it's now on mod_proxy to canonicalize, per PR 69260. * Leave the proper escaping of the URL and the adding of r->args to the proxy module which runs after us after r1920570. Just take care to add r->args in case the proxy rule has the [NE] flag set and tell the proxy module to not escape in this case. * Mention the additional bug Submitted by: jailletc36, ylavic, rpluem Reviewed by: rpluem, ylavic, covener Github: closes #484 git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1921299 13f79535-47bb-0310-9956-ffa450edef68 origin: backport, https://github.com/apache/httpd/commit/88ebfaa60d3a1987dda88d74eb820294c16edc3d bug: https://bz.apache.org/bugzilla/show_bug.cgi?id=69241 bug-debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1081266 --- modules/mappers/mod_rewrite.c | 38 ++++++++++++++++++++++++++------------ modules/proxy/mod_proxy.c | 13 ++++++------- 2 files changed, 32 insertions(+), 19 deletions(-) diff --git a/modules/mappers/mod_rewrite.c b/modules/mappers/mod_rewrite.c index c8c5dbd..13f4dde 100644 --- a/modules/mappers/mod_rewrite.c +++ b/modules/mappers/mod_rewrite.c @@ -5009,7 +5009,7 @@ static int hook_uri2file(request_rec *r) } if ((r->args != NULL) && ((r->proxyreq == PROXYREQ_PROXY) - || (rulestatus == ACTION_NOESCAPE))) { + || apr_table_get(r->notes, "proxy-nocanon"))) { /* see proxy_http:proxy_http_canon() */ r->filename = apr_pstrcat(r->pool, r->filename, "?", r->args, NULL); @@ -5300,13 +5300,28 @@ static int hook_fixup(request_rec *r) if (to_proxyreq) { /* it should go on as an internal proxy request */ - /* make sure the QUERY_STRING and - * PATH_INFO parts get incorporated + /* check if the proxy module is enabled, so + * we can actually use it! + */ + if (!proxy_available) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10160) + "attempt to make remote request from mod_rewrite " + "without proxy enabled: %s", r->filename); + return HTTP_FORBIDDEN; + } + + if (rulestatus == ACTION_NOESCAPE) { + apr_table_setn(r->notes, "proxy-nocanon", "1"); + } + + /* make sure the QUERY_STRING gets incorporated in the case + * [NE] was specified on the Proxy rule. We are preventing + * mod_proxy canon handler from incorporating r->args as well + * as escaping the URL. * (r->path_info was already appended by the * rewriting engine because of the per-dir context!) */ - if (r->args != NULL) { - /* see proxy_http:proxy_http_canon() */ + if ((r->args != NULL) && apr_table_get(r->notes, "proxy-nocanon")) { r->filename = apr_pstrcat(r->pool, r->filename, "?", r->args, NULL); } @@ -5606,10 +5621,7 @@ static void ap_register_rewrite_mapfunc(char *name, rewrite_mapfunc_t *func) static void register_hooks(apr_pool_t *p) { - /* fixup after mod_proxy, so that the proxied url will not - * escaped accidentally by mod_proxy's fixup. - */ - static const char * const aszPre[]={ "mod_proxy.c", NULL }; + static const char * const aszModProxy[] = { "mod_proxy.c", NULL }; /* make the hashtable before registering the function, so that * other modules are prevented from accessing uninitialized memory. @@ -5621,10 +5633,12 @@ static void register_hooks(apr_pool_t *p) ap_hook_pre_config(pre_config, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_post_config(post_config, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_child_init(init_child, NULL, NULL, APR_HOOK_MIDDLE); - - ap_hook_fixups(hook_fixup, aszPre, NULL, APR_HOOK_FIRST); + + /* allow to change the uri before mod_proxy takes over it */ + ap_hook_translate_name(hook_uri2file, NULL, aszModProxy, APR_HOOK_FIRST); + /* fixup before mod_proxy so that a [P] URL gets fixed up there */ + ap_hook_fixups(hook_fixup, NULL, aszModProxy, APR_HOOK_FIRST); ap_hook_fixups(hook_mimetype, NULL, NULL, APR_HOOK_LAST); - ap_hook_translate_name(hook_uri2file, NULL, NULL, APR_HOOK_FIRST); } /* the main config structure */ diff --git a/modules/proxy/mod_proxy.c b/modules/proxy/mod_proxy.c index 16cd5aa..4047d58 100644 --- a/modules/proxy/mod_proxy.c +++ b/modules/proxy/mod_proxy.c @@ -3349,27 +3349,26 @@ static int proxy_pre_config(apr_pool_t *pconf, apr_pool_t *plog, } static void register_hooks(apr_pool_t *p) { - /* fixup before mod_rewrite, so that the proxied url will not - * escaped accidentally by our fixup. - */ - static const char * const aszSucc[] = { "mod_rewrite.c", NULL}; /* Only the mpm_winnt has child init hook handler. * make sure that we are called after the mpm * initializes. */ static const char *const aszPred[] = { "mpm_winnt.c", "mod_proxy_balancer.c", "mod_proxy_hcheck.c", NULL}; + static const char * const aszModRewrite[] = { "mod_rewrite.c", NULL }; + /* handler */ ap_hook_handler(proxy_handler, NULL, NULL, APR_HOOK_FIRST); /* filename-to-URI translation */ ap_hook_pre_translate_name(proxy_pre_translate_name, NULL, NULL, APR_HOOK_MIDDLE); - ap_hook_translate_name(proxy_translate_name, aszSucc, NULL, + /* mod_rewrite has a say on the uri before proxy translation */ + ap_hook_translate_name(proxy_translate_name, aszModRewrite, NULL, APR_HOOK_FIRST); /* walk entries and suppress default TRACE behavior */ ap_hook_map_to_storage(proxy_map_location, NULL,NULL, APR_HOOK_FIRST); - /* fixups */ - ap_hook_fixups(proxy_fixup, NULL, aszSucc, APR_HOOK_FIRST); + /* fixup after mod_rewrite so that a [P] URL from there gets fixed up */ + ap_hook_fixups(proxy_fixup, aszModRewrite, NULL, APR_HOOK_FIRST); /* post read_request handling */ ap_hook_post_read_request(proxy_detect, NULL, NULL, APR_HOOK_FIRST); /* pre config handling */