httpd/httpd-2.4.51-CVE-2021-44224.patch
Luboš Uhliarik bdf0e9e785 Resolves: #2065251 - CVE-2022-22720 httpd: HTTP request smuggling
vulnerability in Apache HTTP Server 2.4.52 and earlier
Resolves: #2066311 - CVE-2021-44224 httpd: possible NULL dereference or SSRF
  in forward proxy configurations
2022-03-21 14:25:44 +01:00

253 lines
10 KiB
Diff

diff --git a/include/http_protocol.h b/include/http_protocol.h
index 9ccac89..20bd202 100644
--- a/include/http_protocol.h
+++ b/include/http_protocol.h
@@ -96,6 +96,13 @@ AP_DECLARE(void) ap_get_mime_headers(request_rec *r);
AP_DECLARE(void) ap_get_mime_headers_core(request_rec *r,
apr_bucket_brigade *bb);
+/**
+ * Run post_read_request hook and validate.
+ * @param r The current request
+ * @return OK or HTTP_...
+ */
+AP_DECLARE(int) ap_post_read_request(request_rec *r);
+
/* Finish up stuff after a request */
/**
diff --git a/modules/http/http_request.c b/modules/http/http_request.c
index c9ae5af..d59cfe2 100644
--- a/modules/http/http_request.c
+++ b/modules/http/http_request.c
@@ -680,7 +680,7 @@ static request_rec *internal_internal_redirect(const char *new_uri,
* to do their thing on internal redirects as well. Perhaps this is a
* misnamed function.
*/
- if ((access_status = ap_run_post_read_request(new))) {
+ if ((access_status = ap_post_read_request(new))) {
ap_die(access_status, new);
return NULL;
}
diff --git a/modules/proxy/mod_proxy.c b/modules/proxy/mod_proxy.c
index ee4f1fb..ff9f81d 100644
--- a/modules/proxy/mod_proxy.c
+++ b/modules/proxy/mod_proxy.c
@@ -777,11 +777,12 @@ static int proxy_detect(request_rec *r)
if (conf->req && r->parsed_uri.scheme) {
/* but it might be something vhosted */
- if (!(r->parsed_uri.hostname
- && !ap_cstr_casecmp(r->parsed_uri.scheme, ap_http_scheme(r))
- && ap_matches_request_vhost(r, r->parsed_uri.hostname,
- (apr_port_t)(r->parsed_uri.port_str ? r->parsed_uri.port
- : ap_default_port(r))))) {
+ 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
+ : ap_default_port(r)))) {
r->proxyreq = PROXYREQ_PROXY;
r->uri = r->unparsed_uri;
r->filename = apr_pstrcat(r->pool, "proxy:", r->uri, NULL);
@@ -2021,6 +2022,7 @@ static const char *
struct proxy_alias *new;
char *f = cmd->path;
char *r = NULL;
+ const char *real;
char *word;
apr_table_t *params = apr_table_make(cmd->pool, 5);
const apr_array_header_t *arr;
@@ -2107,6 +2109,10 @@ static const char *
if (r == NULL) {
return "ProxyPass|ProxyPassMatch needs a path when not defined in a location";
}
+ if (!(real = ap_proxy_de_socketfy(cmd->temp_pool, r))) {
+ return "ProxyPass|ProxyPassMatch uses an invalid \"unix:\" URL";
+ }
+
/* if per directory, save away the single alias */
if (cmd->path) {
@@ -2123,7 +2129,7 @@ static const char *
}
new->fake = apr_pstrdup(cmd->pool, f);
- new->real = apr_pstrdup(cmd->pool, ap_proxy_de_socketfy(cmd->pool, r));
+ new->real = apr_pstrdup(cmd->pool, real);
new->flags = flags;
if (worker_type & AP_PROXY_WORKER_IS_MATCH) {
new->regex = ap_pregcomp(cmd->pool, f, AP_REG_EXTENDED);
@@ -2649,6 +2655,7 @@ static const char *add_member(cmd_parms *cmd, void *dummy, const char *arg)
proxy_worker *worker;
char *path = cmd->path;
char *name = NULL;
+ const char *real;
char *word;
apr_table_t *params = apr_table_make(cmd->pool, 5);
const apr_array_header_t *arr;
@@ -2689,6 +2696,9 @@ static const char *add_member(cmd_parms *cmd, void *dummy, const char *arg)
return "BalancerMember must define balancer name when outside <Proxy > section";
if (!name)
return "BalancerMember must define remote proxy server";
+ if (!(real = ap_proxy_de_socketfy(cmd->temp_pool, name))) {
+ return "BalancerMember uses an invalid \"unix:\" URL";
+ }
ap_str_tolower(path); /* lowercase scheme://hostname */
@@ -2701,8 +2711,7 @@ static const char *add_member(cmd_parms *cmd, void *dummy, const char *arg)
}
/* Try to find existing worker */
- worker = ap_proxy_get_worker(cmd->temp_pool, balancer, conf,
- ap_proxy_de_socketfy(cmd->temp_pool, name));
+ worker = ap_proxy_get_worker(cmd->temp_pool, balancer, conf, real);
if (!worker) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, cmd->server, APLOGNO(01147)
"Defining worker '%s' for balancer '%s'",
@@ -2799,9 +2808,14 @@ static const char *
}
}
else {
+ const char *real;
+
+ if (!(real = ap_proxy_de_socketfy(cmd->temp_pool, name))) {
+ return "ProxySet uses an invalid \"unix:\" URL";
+ }
+
worker = ap_proxy_get_worker_ex(cmd->temp_pool, NULL, conf,
- ap_proxy_de_socketfy(cmd->temp_pool, name),
- worker_type);
+ real, worker_type);
if (!worker) {
if (in_proxy_section) {
err = ap_proxy_define_worker_ex(cmd->pool, &worker, NULL,
@@ -2944,9 +2958,14 @@ static const char *proxysection(cmd_parms *cmd, void *mconfig, const char *arg)
}
}
else {
+ const char *real;
+
+ if (!(real = ap_proxy_de_socketfy(cmd->temp_pool, conf->p))) {
+ return "<Proxy/ProxyMatch > uses an invalid \"unix:\" URL";
+ }
+
worker = ap_proxy_get_worker_ex(cmd->temp_pool, NULL, sconf,
- ap_proxy_de_socketfy(cmd->temp_pool, conf->p),
- worker_type);
+ real, worker_type);
if (!worker) {
err = ap_proxy_define_worker_ex(cmd->pool, &worker, NULL, sconf,
conf->p, worker_type);
diff --git a/modules/proxy/mod_proxy.h b/modules/proxy/mod_proxy.h
index 044a6c4..c21c4d8 100644
--- a/modules/proxy/mod_proxy.h
+++ b/modules/proxy/mod_proxy.h
@@ -751,6 +751,7 @@ 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 8225045..cbe300f 100644
--- a/modules/proxy/proxy_util.c
+++ b/modules/proxy/proxy_util.c
@@ -1741,7 +1741,12 @@ PROXY_DECLARE(proxy_worker *) ap_proxy_get_worker_ex(apr_pool_t *p,
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, ':');
if (c == NULL || c[1] != '/' || c[2] != '/' || c[3] == '\0') {
@@ -2323,22 +2328,22 @@ 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);
- *balancer = NULL;
*worker = conf->forward;
access_status = OK;
/*
@@ -2352,8 +2357,8 @@ PROXY_DECLARE(int) ap_proxy_pre_request(proxy_worker **worker,
else if (r->proxyreq == PROXYREQ_REVERSE) {
if (conf->reverse) {
ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
- "*: using default reverse proxy worker for %s (no keepalive)", *url);
- *balancer = NULL;
+ "*: using default reverse proxy worker for %s "
+ "(no keepalive)", *url);
*worker = conf->reverse;
access_status = OK;
/*
diff --git a/server/protocol.c b/server/protocol.c
index 3d74c5b..2214f72 100644
--- a/server/protocol.c
+++ b/server/protocol.c
@@ -1548,7 +1548,7 @@ request_rec *ap_read_request(conn_rec *conn)
/* we may have switched to another server */
apply_server_config(r);
- if ((access_status = ap_run_post_read_request(r))) {
+ if ((access_status = ap_post_read_request(r))) {
goto die;
}
@@ -1603,6 +1603,27 @@ ignore:
return NULL;
}
+AP_DECLARE(int) ap_post_read_request(request_rec *r)
+{
+ int status;
+
+ if ((status = ap_run_post_read_request(r))) {
+ return status;
+ }
+
+ /* Enforce http(s) only scheme for non-forward-proxy requests */
+ if (!r->proxyreq
+ && r->parsed_uri.scheme
+ && (ap_cstr_casecmpn(r->parsed_uri.scheme, "http", 4) != 0
+ || (r->parsed_uri.scheme[4] != '\0'
+ && (apr_tolower(r->parsed_uri.scheme[4]) != 's'
+ || r->parsed_uri.scheme[5] != '\0')))) {
+ return HTTP_BAD_REQUEST;
+ }
+
+ return OK;
+}
+
/* if a request with a body creates a subrequest, remove original request's
* input headers which pertain to the body which has already been read.
* out-of-line helper function for ap_set_sub_req_protocol.