-const char cgi_rcs[] = "$Id: cgi.c,v 1.80 2006/12/08 14:45:32 fabiankeil Exp $";
+const char cgi_rcs[] = "$Id: cgi.c,v 1.88 2007/01/23 13:14:32 fabiankeil Exp $";
/*********************************************************************
*
* File : $Source: /cvsroot/ijbswa/current/cgi.c,v $
* Functions declared include:
*
*
- * Copyright : Written by and Copyright (C) 2001 the SourceForge
- * Privoxy team. http://www.privoxy.org/
+ * Copyright : Written by and Copyright (C) 2001-2004, 2006-2007
+ * the SourceForge Privoxy team. http://www.privoxy.org/
*
* Based on the Internet Junkbuster originally written
* by and Copyright (C) 1997 Anonymous Coders and
*
* Revisions :
* $Log: cgi.c,v $
+ * Revision 1.88 2007/01/23 13:14:32 fabiankeil
+ * - Map variables that aren't guaranteed to be
+ * pure ASCII html_encoded.
+ * - Use CGI_PREFIX to generate URL for user manual
+ * CGI page to make sure CGI_SITE_2_PATH is included.
+ *
+ * Revision 1.87 2007/01/22 15:34:13 fabiankeil
+ * - "Protect" against a rather lame JavaScript-based
+ * Privoxy detection "attack" and check the referrer
+ * before delivering the CGI style sheet.
+ * - Move referrer check for unsafe CGI pages into
+ * referrer_is_safe() and log the result.
+ * - Map @url@ in cgi-error-disabled page.
+ * It's required for the "go there anyway" link.
+ * - Mark *csp as immutable for grep_cgi_referrer().
+ *
+ * Revision 1.86 2007/01/09 11:54:26 fabiankeil
+ * Fix strdup() error handling in cgi_error_unknown()
+ * and cgi_error_no_template(). Reported by Markus Elfring.
+ *
+ * Revision 1.85 2007/01/05 14:19:02 fabiankeil
+ * Handle pcrs_execute() errors in template_fill() properly.
+ *
+ * Revision 1.84 2006/12/28 17:54:22 fabiankeil
+ * Fixed gcc43 conversion warnings and replaced sprintf
+ * calls with snprintf to give OpenBSD's gcc one less reason
+ * to complain.
+ *
+ * Revision 1.83 2006/12/17 19:35:19 fabiankeil
+ * Escape ampersand in Privoxy menu.
+ *
+ * Revision 1.82 2006/12/17 17:53:39 fabiankeil
+ * Suppress the toggle link if remote toggling is disabled.
+ *
+ * Revision 1.81 2006/12/09 13:49:16 fabiankeil
+ * Fix configure option --disable-toggle.
+ * Thanks to Peter Thoenen for reporting this.
+ *
* Revision 1.80 2006/12/08 14:45:32 fabiankeil
* Don't lose the FORCE_PREFIX in case of
* connection problems. Fixes #612235.
{ "show-status",
cgi_show_status,
#ifdef FEATURE_CGI_EDIT_ACTIONS
- "View & change the current configuration",
+ "View & change the current configuration",
#else
"View the current configuration",
#endif
cgi_edit_actions_section_swap,
NULL, FALSE /* Swap two sections in the actionsfile */ },
#endif /* def FEATURE_CGI_EDIT_ACTIONS */
+ { "error-favicon.ico",
+ cgi_send_error_favicon,
+ NULL, TRUE /* Sends the favicon image for error pages. */ },
+ { "favicon.ico",
+ cgi_send_default_favicon,
+ NULL, TRUE /* Sends the default favicon image. */ },
{ "robots.txt",
cgi_robots_txt,
NULL, TRUE /* Sends a robots.txt file to tell robots to go away. */ },
NULL, TRUE /* Send a built-in image */ },
{ "send-stylesheet",
cgi_send_stylesheet,
- NULL, TRUE /* Send templates/cgi-style.css */ },
+ NULL, FALSE /* Send templates/cgi-style.css */ },
{ "t",
cgi_transparent_image,
NULL, TRUE /* Send a transparent image (short name) */ },
* Returns : pointer to value (no copy!), or NULL if none found.
*
*********************************************************************/
-char *grep_cgi_referrer(struct client_state *csp)
+char *grep_cgi_referrer(const struct client_state *csp)
{
struct list_entry *p;
}
+/*********************************************************************
+ *
+ * Function : referrer_is_safe
+ *
+ * Description : Decides whether we trust the Referer for
+ * CGI pages which are only meant to be reachable
+ * through Privoxy's web interface directly.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ *
+ * Returns : TRUE if the referrer is safe, or
+ * FALSE if the referrer is unsafe or not set.
+ *
+ *********************************************************************/
+int referrer_is_safe (const struct client_state *csp)
+{
+ char *referrer;
+ const char alternative_prefix[] = "http://" CGI_SITE_1_HOST "/";
+
+ referrer = grep_cgi_referrer(csp);
+
+ if (NULL == referrer)
+ {
+ /* No referrer, no access */
+ 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)))))
+ {
+ /* Trustworthy referrer */
+ log_error(LOG_LEVEL_CGI, "Granting access to %s, referrer %s is trustworthy.",
+ csp->http->url, referrer);
+
+ return TRUE;
+ }
+ else
+ {
+ /* Untrustworthy referrer */
+ log_error(LOG_LEVEL_ERROR, "Denying access to %s, referrer %s isn't trustworthy.",
+ csp->http->url, referrer);
+ }
+
+ return FALSE;
+
+}
+
/*********************************************************************
*
* Function : dispatch_known_cgi
struct http_response *rsp;
char *query_args_start;
char *path_copy;
- char *referrer;
jb_err err;
if (NULL == (path_copy = strdup(path)))
* If the called CGI is either harmless, or referred
* from a trusted source, start it.
*/
- if (d->harmless
- || ((NULL != (referrer = grep_cgi_referrer(csp)))
- && (0 == strncmp(referrer, CGI_PREFIX, sizeof(CGI_PREFIX)-1)))
- )
+ if (d->harmless || referrer_is_safe(csp))
{
err = (d->handler)(csp, rsp, param_list);
}
ch = *(lookup(parameters, param_name));
if ((ch >= 'a') && (ch <= 'z'))
{
- ch = ch - 'a' + 'A';
+ ch = (char)(ch - 'a' + 'A');
}
return ch;
return JB_ERR_CGI_PARAMS;
}
- ch -= '0';
+ ch = (char)(ch - '0');
/* Note:
*
return JB_ERR_CGI_PARAMS;
}
- value = value * 10 + ch;
+ value = value * 10 + (unsigned)ch;
}
/* Success */
* Description : CGI function that is called to generate an error
* response if the actions editor or toggle CGI are
* accessed despite having being disabled at compile-
- * or run-time.
+ * or run-time, or if the user followed an untrusted link
+ * to access a unsafe CGI feature that is only reachable
+ * through Privoxy directly.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
assert(csp);
assert(rsp);
- if (NULL == (exports = default_exports(csp, NULL)))
+ if (NULL == (exports = default_exports(csp, "cgi-error-disabled")))
{
return JB_ERR_MEMORY;
}
+ if (map(exports, "url", 1, html_encode(csp->http->url), 0))
+ {
+ /* Not important enough to do anything */
+ log_error(LOG_LEVEL_ERROR, "Failed to fill in url.");
+ }
return template_fill_for_cgi(csp, "cgi-error-disabled", exports, rsp);
}
strcat(rsp->body, body_suffix);
rsp->status = strdup(status);
- if (rsp->body == NULL)
+ if (rsp->status == NULL)
{
return JB_ERR_MEMORY;
}
rsp->head_length = 0;
rsp->is_static = 0;
- sprintf(errnumbuf, "%d", error_to_report);
+ snprintf(errnumbuf, sizeof(errnumbuf), "%d", error_to_report);
rsp->body = malloc(strlen(body_prefix) + strlen(errnumbuf) + strlen(body_suffix) + 1);
if (rsp->body == NULL)
strcat(rsp->body, body_suffix);
rsp->status = strdup(status);
- if (rsp->body == NULL)
+ if (rsp->status == NULL)
{
return JB_ERR_MEMORY;
}
/*
* Fill in the HTTP Status
*/
- sprintf(buf, "HTTP/1.0 %s", rsp->status ? rsp->status : "200 OK");
+ snprintf(buf, sizeof(buf), "HTTP/1.0 %s", rsp->status ? rsp->status : "200 OK");
err = enlist_first(rsp->headers, buf);
/*
}
if (!err)
{
- sprintf(buf, "Content-Length: %d", (int)rsp->content_length);
+ snprintf(buf, sizeof(buf), "Content-Length: %d", (int)rsp->content_length);
err = enlist(rsp->headers, buf);
}
* Caller must free().
* 2 : exports = map with fill in symbol -> name pairs
*
- * Returns : JB_ERR_OK on success
+ * Returns : JB_ERR_OK on success (and for uncritical errors)
* JB_ERR_MEMORY on out-of-memory error
*
*********************************************************************/
}
else
{
- pcrs_execute(job, file_buffer, size, &tmp_out_buffer, &size);
- free(file_buffer);
+ error = pcrs_execute(job, file_buffer, size, &tmp_out_buffer, &size);
+
pcrs_free_job(job);
if (NULL == tmp_out_buffer)
{
*template_ptr = NULL;
return JB_ERR_MEMORY;
}
- file_buffer = tmp_out_buffer;
+
+ if (error < 0)
+ {
+ /*
+ * Substitution failed, keep the original buffer,
+ * log the problem and ignore it.
+ *
+ * The user might see some unresolved @CGI_VARIABLES@,
+ * but returning a special CGI error page seems unreasonable
+ * and could mask more important error messages.
+ */
+ free(tmp_out_buffer);
+ log_error(LOG_LEVEL_ERROR, "Failed to execute s/%s/%s/%s. %s",
+ buf, m->value, flags, pcrs_strerror(error));
+ }
+ else
+ {
+ /* Substitution succeeded, use modified buffer. */
+ free(file_buffer);
+ file_buffer = tmp_out_buffer;
+ }
}
}
if (!err) err = map(exports, "my-hostname", 1, html_encode(csp->my_hostname ? csp->my_hostname : "unknown"), 0);
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), 0);
+ if (!err) err = map(exports, "menu", 1, make_menu(caller, csp->config->feature_flags), 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))
{
- if (!err) err = map(exports, "user-manual", 1, csp->config->usermanual ,1);
+ /* Manual is located somewhere else, just link to it. */
+ if (!err) err = map(exports, "user-manual", 1, html_encode(csp->config->usermanual), 0);
}
else
{
- if (!err) err = map(exports, "user-manual", 1, "http://"CGI_SITE_2_HOST"/user-manual/" ,1);
+ /* 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, "actions-help-prefix", 1, ACTIONS_HELP_PREFIX ,1);
#ifdef FEATURE_TOGGLE
*
* Description : Returns an HTML-formatted menu of the available
* unhidden CGIs, excluding the one given in <self>
+ * and the toggle CGI if toggling is disabled.
*
- * Parameters : self = name of CGI to leave out, can be NULL for
+ * Parameters :
+ * 1 : 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)
+char *make_menu(const char *self, const unsigned feature_flags)
{
const struct cgi_dispatcher *d;
char *result = strdup("");
/* List available unhidden CGI's and export as "other-cgis" */
for (d = cgi_dispatchers; d->name; d++)
{
+
+#ifdef FEATURE_TOGGLE
+ if (!(feature_flags & RUNTIME_FEATURE_CGI_TOGGLE) && !strcmp(d->name, "toggle"))
+ {
+ /*
+ * Suppress the toggle link if remote toggling is disabled.
+ */
+ continue;
+ }
+#endif /* def FEATURE_TOGGLE */
+
if (d->description && strcmp(d->name, self))
{
- string_append(&result, "<li><a href=\"" CGI_PREFIX);
+ char *html_encoded_prefix;
+
+ string_append(&result, "<li><a href=\"");
+ html_encoded_prefix = html_encode(CGI_PREFIX);
+ if (html_encoded_prefix == NULL)
+ {
+ return NULL;
+ }
+ else
+ {
+ string_append(&result, html_encoded_prefix);
+ free(html_encoded_prefix);
+ }
string_append(&result, d->name);
string_append(&result, "\">");
string_append(&result, d->description);
- string_append(&result, "</a></li>");
+ string_append(&result, "</a></li>\n");
}
}