From: Fabian Keil <fk@fabiankeil.de>
Date: Wed, 27 May 2020 07:02:47 +0000 (+0200)
Subject: If a dynamic CGI page has been requested through https, use https URLs
X-Git-Tag: v_3_0_29~369
X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=commitdiff_plain;h=3dfff657b0fc14d0af804e566b69e4d83629ddc6

If a dynamic CGI page has been requested through https, use https URLs

... and accept https versions of the CGI pages as trusted referrers.

This prevents mixed-content warnings when accessing the
CGI pages through https.

Sponsored by: Robert Klemme
---

diff --git a/cgi.c b/cgi.c
index 96ce16f3..acae0fe7 100644
--- a/cgi.c
+++ b/cgi.c
@@ -62,12 +62,17 @@
 #if defined(FEATURE_CGI_EDIT_ACTIONS) || defined(FEATURE_TOGGLE)
 #include "cgiedit.h"
 #endif /* defined(FEATURE_CGI_EDIT_ACTIONS) || defined (FEATURE_TOGGLE) */
+#ifdef FEATURE_HTTPS_INSPECTION
+#include "ssl.h"
+#endif
 
 /* loadcfg.h is for global_toggle_state only */
 #include "loadcfg.h"
 /* jcc.h is for mutex semaphore globals only */
 #include "jcc.h"
 
+static char *make_menu(const struct client_state *csp, const char *self);
+
 /*
  * List of CGI functions: name, handler, description
  * Note: Do NOT use single quotes in the description;
@@ -401,8 +406,13 @@ struct http_response *dispatch_cgi(struct client_state *csp)
 static char *grep_cgi_referrer(const struct client_state *csp)
 {
    struct list_entry *p;
+   struct list_entry *first_header =
+#ifdef FEATURE_HTTPS_INSPECTION
+      client_use_ssl(csp) ? csp->https_headers->first :
+#endif
+      csp->headers->first;
 
-   for (p = csp->headers->first; p != NULL; p = p->next)
+   for (p = first_header; p != NULL; p = p->next)
    {
       if (p->str == NULL) continue;
       if (strncmpic(p->str, "Referer: ", 9) == 0)
@@ -434,6 +444,7 @@ static int referrer_is_safe(const struct client_state *csp)
 {
    char *referrer;
    static const char alternative_prefix[] = "http://" CGI_SITE_1_HOST "/";
+   static const char alt_prefix_https[] = "https://" CGI_SITE_1_HOST "/";
    const char *trusted_cgi_referrer = csp->config->trusted_cgi_referrer;
 
    referrer = grep_cgi_referrer(csp);
@@ -444,8 +455,12 @@ static int referrer_is_safe(const struct client_state *csp)
       log_error(LOG_LEVEL_ERROR, "Denying access to %s. No referrer found.",
          csp->http->url);
    }
-   else if ((0 == strncmp(referrer, CGI_PREFIX, sizeof(CGI_PREFIX)-1)
-         || (0 == strncmp(referrer, alternative_prefix, strlen(alternative_prefix)))))
+   else if ((0 == strncmp(referrer, CGI_PREFIX, sizeof(CGI_PREFIX)-1))
+#ifdef FEATURE_HTTPS_INSPECTION
+         || (0 == strncmp(referrer, CGI_PREFIX_HTTPS, sizeof(CGI_PREFIX_HTTPS)-1))
+         || (0 == strncmp(referrer, alt_prefix_https, strlen(alt_prefix_https)))
+#endif
+         || (0 == strncmp(referrer, alternative_prefix, strlen(alternative_prefix))))
    {
       /* Trustworthy referrer */
       log_error(LOG_LEVEL_CGI, "Granting access to %s, referrer %s is trustworthy.",
@@ -2194,8 +2209,15 @@ struct map *default_exports(const struct client_state *csp, const char *caller)
    if (!err) err = map(exports, "my-hostname",   1, html_encode(hostname ? hostname : "unknown"), 0);
    freez(hostname);
    if (!err) err = map(exports, "homepage",      1, html_encode(HOME_PAGE_URL), 0);
-   if (!err) err = map(exports, "default-cgi",   1, html_encode(CGI_PREFIX), 0);
-   if (!err) err = map(exports, "menu",          1, make_menu(caller, csp->config->feature_flags), 0);
+   if (!err)
+   {
+      err = map(exports, "default-cgi",   1, html_encode(
+#ifdef FEATURE_HTTPS_INSPECTION
+        client_use_ssl(csp) ? CGI_PREFIX_HTTPS :
+#endif
+        CGI_PREFIX), 0);
+   }
+   if (!err) err = map(exports, "menu",          1, make_menu(csp, caller), 0);
    if (!err) err = map(exports, "code-status",   1, CODE_STATUS, 1);
    if (!strncmpic(csp->config->usermanual, "file://", 7) ||
        !strncmpic(csp->config->usermanual, "http", 4))
@@ -2206,7 +2228,14 @@ struct map *default_exports(const struct client_state *csp, const char *caller)
    else
    {
       /* Manual is delivered by Privoxy. */
-      if (!err) err = map(exports, "user-manual", 1, html_encode(CGI_PREFIX"user-manual/"), 0);
+      if (!err)
+      {
+         err = map(exports, "user-manual", 1, html_encode(
+#ifdef FEATURE_HTTPS_INSPECTION
+           client_use_ssl(csp) ? CGI_PREFIX_HTTPS"user-manual/" :
+#endif
+           CGI_PREFIX"user-manual/"), 0);
+      }
    }
    if (!err) err = map(exports, "actions-help-prefix", 1, ACTIONS_HELP_PREFIX ,1);
 #ifdef FEATURE_TOGGLE
@@ -2383,15 +2412,14 @@ jb_err map_conditional(struct map *exports, const char *name, int choose_first)
  *                and the toggle CGI if toggling is disabled.
  *
  * Parameters  :
- *          1  :  self = name of CGI to leave out, can be NULL for
+ *          1  :  csp = Current client state (buffers, headers, etc...)
+ *          2  :  self = name of CGI to leave out, can be NULL for
  *                complete listing.
- *          2  :  feature_flags = feature bitmap from csp->config
- *
  *
  * Returns     :  menu string, or NULL on out-of-memory error.
  *
  *********************************************************************/
-char *make_menu(const char *self, const unsigned feature_flags)
+char *make_menu(const struct client_state *csp, const char *self)
 {
    const struct cgi_dispatcher *d;
    char *result = strdup("");
@@ -2406,7 +2434,7 @@ char *make_menu(const char *self, const unsigned feature_flags)
    {
 
 #ifdef FEATURE_TOGGLE
-      if (!(feature_flags & RUNTIME_FEATURE_CGI_TOGGLE) && !strcmp(d->name, "toggle"))
+      if (!(csp->config->feature_flags & RUNTIME_FEATURE_CGI_TOGGLE) && !strcmp(d->name, "toggle"))
       {
          /*
           * Suppress the toggle link if remote toggling is disabled.
@@ -2424,7 +2452,11 @@ char *make_menu(const char *self, const unsigned feature_flags)
           * the "blocked" template's JavaScript.
           */
          string_append(&result, "<li><a href=\"");
-         html_encoded_prefix = html_encode(CGI_PREFIX);
+         html_encoded_prefix = html_encode(
+#ifdef FEATURE_HTTPS_INSPECTION
+            client_use_ssl(csp) ? CGI_PREFIX_HTTPS :
+#endif
+            CGI_PREFIX);
          if (html_encoded_prefix == NULL)
          {
             return NULL;
diff --git a/cgi.h b/cgi.h
index a2cf4331..e4a132ee 100644
--- a/cgi.h
+++ b/cgi.h
@@ -110,7 +110,6 @@ extern char *compress_buffer(char *buffer, size_t *buffer_length, int compressio
  */
 extern void get_http_time(int time_offset, char *buf, size_t buffer_size);
 extern char *add_help_link(const char *item, struct configuration_spec *config);
-extern char *make_menu(const char *self, const unsigned feature_flags);
 extern char *dump_map(const struct map *the_map);
 
 /*
diff --git a/project.h b/project.h
index 8b132a57..943e66da 100644
--- a/project.h
+++ b/project.h
@@ -1603,6 +1603,7 @@ struct configuration_spec
  * INCLUDES the trailing slash.
  */
 #define CGI_PREFIX  "http://" CGI_SITE_2_HOST CGI_SITE_2_PATH "/"
+#define CGI_PREFIX_HTTPS "https://" CGI_SITE_2_HOST CGI_SITE_2_PATH "/"
 
 #endif /* ndef PROJECT_H_INCLUDED */