Http-proxy: fix bug preventing proxy credentials caching

Caching proxy credentials was not working due to the
lack of handling already defined creds in get_user_pass(),
which prevented the caching from working properly.

Fix this issue by getting the value of c->first_time,
that indicates if we're at the first iteration
of the main loop and use it as second argument of the
get_user_pass_http(). Otherwise, on SIGUSR1 or SIGHUP
upon instance context restart credentials would be erased
every time.

The nocache member has been added to the struct
http_proxy_options and also a getter method to retrieve
that option from ssl has been added, by doing this
we're able to erase previous queried user credentials
to ensure correct operation.

Fixes: Trac #1187
Signed-off-by: Gianmarco De Gregori <[email protected]>
Acked-by: Gert Doering <[email protected]>
Change-Id: Ia3e06c0832c4ca0ab868c845279fb71c01a1a78a
Acked-by: Frank Lichtenheld <[email protected]>
Message-Id: <[email protected]>
URL: https://www.mail-archive.com/[email protected]/msg28835.html
Signed-off-by: Gert Doering <[email protected]>

doc/man-sections/generic-options.rst

@@ -19,9 +19,6 @@ which mode OpenVPN is configured as.
   When using ``--auth-nocache`` in combination with a user/password file
   and ``--chroot`` or ``--daemon``, make sure to use an absolute path.
 
-  This directive does not affect the ``--http-proxy`` username/password.
-  It is always cached.
-
 --cd dir
   Change directory to ``dir`` prior to reading any files such as
   configuration files, key files, scripts, etc. ``dir`` should be an

src/openvpn/init.c

@@ -691,6 +691,8 @@ init_proxy_dowork(struct context *c)
 
     if (c->options.ce.http_proxy_options)
     {
+        c->options.ce.http_proxy_options->first_time = c->first_time;
+
         /* Possible HTTP proxy user/pass input */
         c->c1.http_proxy = http_proxy_new(c->options.ce.http_proxy_options);
         if (c->c1.http_proxy)

src/openvpn/options.c

@@ -1650,6 +1650,7 @@ show_http_proxy_options(const struct http_proxy_options *o)
     SHOW_STR(auth_file);
     SHOW_STR(auth_file_up);
     SHOW_BOOL(inline_creds);
+    SHOW_BOOL(nocache);
     SHOW_STR(http_version);
     SHOW_STR(user_agent);
     for  (i = 0; i < MAX_CUSTOM_HTTP_HEADER && o->custom_headers[i].name; i++)
@@ -3151,6 +3152,11 @@ options_postprocess_mutate_ce(struct options *o, struct connection_entry *ce)
         ce->flags |= CE_DISABLED;
     }
 
+    if (ce->http_proxy_options)
+    {
+        ce->http_proxy_options->nocache = ssl_get_auth_nocache();
+    }
+
     /* our socks code is not fully IPv6 enabled yet (TCP works, UDP not)
      * so fall back to IPv4-only (trac #1221)
      */

src/openvpn/proxy.c

@@ -276,7 +276,7 @@ get_user_pass_http(struct http_proxy_info *p, const bool force)
         {
             auth_file = p->options.auth_file_up;
         }
-        if (p->queried_creds)
+        if (p->queried_creds && !static_proxy_user_pass.nocache)
         {
             flags |= GET_USER_PASS_PREVIOUS_CREDS_FAILED;
         }
@@ -288,9 +288,14 @@ get_user_pass_http(struct http_proxy_info *p, const bool force)
                       auth_file,
                       UP_TYPE_PROXY,
                       flags);
-        p->queried_creds = true;
-        p->up = static_proxy_user_pass;
+        static_proxy_user_pass.nocache = p->options.nocache;
     }
+
+    /*
+     * Using cached credentials
+     */
+    p->queried_creds = true;
+    p->up = static_proxy_user_pass;
 }
 
 #if 0
@@ -542,7 +547,7 @@ http_proxy_new(const struct http_proxy_options *o)
      * we know whether we need any. */
     if (p->auth_method == HTTP_AUTH_BASIC || p->auth_method == HTTP_AUTH_NTLM2)
     {
-        get_user_pass_http(p, true);
+        get_user_pass_http(p, p->options.first_time);
     }
 
 #if !NTLM
@@ -656,6 +661,11 @@ establish_http_proxy_passthru(struct http_proxy_info *p,
         || p->auth_method == HTTP_AUTH_NTLM2)
     {
         get_user_pass_http(p, false);
+
+        if (p->up.nocache)
+        {
+            clear_user_pass_http();
+        }
     }
 
     /* are we being called again after getting the digest server nonce in the previous transaction? */
@@ -1036,13 +1046,6 @@ establish_http_proxy_passthru(struct http_proxy_info *p,
             }
             goto error;
         }
-
-        /* clear state */
-        if (p->options.auth_retry)
-        {
-            clear_user_pass_http();
-        }
-        store_proxy_authenticate(p, NULL);
     }
 
     /* check return code, success = 200 */

src/openvpn/proxy.h

@@ -57,6 +57,8 @@ struct http_proxy_options {
     const char *user_agent;
     struct http_custom_header custom_headers[MAX_CUSTOM_HTTP_HEADER];
     bool inline_creds; /* auth_file_up is inline credentials */
+    bool first_time; /* indicates if we need to wipe user creds at the first iteration of the main loop */
+    bool nocache;
 };
 
 struct http_proxy_options_simple {

src/openvpn/ssl.c

@@ -334,6 +334,15 @@ ssl_set_auth_nocache(void)
     auth_user_pass.nocache = true;
 }
 
+/*
+ * Get the password caching
+ */
+bool
+ssl_get_auth_nocache(void)
+{
+    return passbuf.nocache;
+}
+
 /*
  * Set an authentication token
  */

src/openvpn/ssl.h

@@ -396,6 +396,11 @@ void auth_user_pass_setup(const char *auth_file, bool is_inline,
  */
 void ssl_set_auth_nocache(void);
 
+/*
+ * Getter method for retrieving the auth-nocache option.
+ */
+bool ssl_get_auth_nocache(void);
+
 /*
  * Purge any stored authentication information, both for key files and tunnel
  * authentication. If PCKS #11 is enabled, purge authentication for that too.