-const char parsers_rcs[] = "$Id: parsers.c,v 1.107 2007/08/28 18:16:32 fabiankeil Exp $";
+const char parsers_rcs[] = "$Id: parsers.c,v 1.108 2007/08/28 18:21:03 fabiankeil Exp $";
/*********************************************************************
*
* File : $Source: /cvsroot/ijbswa/current/parsers.c,v $
*
* Revisions :
* $Log: parsers.c,v $
+ * Revision 1.108 2007/08/28 18:21:03 fabiankeil
+ * A bunch of whitespace fixes, pointy hat to me.
+ *
* Revision 1.107 2007/08/28 18:16:32 fabiankeil
* Fix possible memory corruption in server_http, make sure it's not
* executed for ordinary server headers and mark some problems for later.
static jb_err client_x_forwarded_adder(struct client_state *csp);
static jb_err connection_close_adder (struct client_state *csp);
+static jb_err create_forged_referrer(char **header, const char *hostport);
+static jb_err create_fake_referrer(char **header, const char *fake_referrer);
+static jb_err handle_conditional_hide_referrer_parameter(char **header,
+ const char *host, const int parameter_conditional_block);
+
const struct parsers client_patterns[] = {
{ "referer:", 8, client_referrer },
{ "user-agent:", 11, client_uagent },
return JB_ERR_OK;
}
+
/*********************************************************************
*
* Function : client_referrer
*********************************************************************/
static jb_err client_referrer(struct client_state *csp, char **header)
{
- const char *newval;
- const char *host;
- char *referer;
- size_t hostlenght;
+ const char *parameter;
+ /* booleans for parameters we have to check multiple times */
+ int parameter_conditional_block;
+ int parameter_conditional_forge;
#ifdef FEATURE_FORCE_LOAD
- /* Since the referrer can include the prefix even
+ /*
+ * Since the referrer can include the prefix even
* if the request itself is non-forced, we must
- * clean it unconditionally
+ * clean it unconditionally.
+ *
+ * XXX: strclean is too broad
*/
strclean(*header, FORCE_PREFIX);
#endif /* def FEATURE_FORCE_LOAD */
- /*
- * Are we sending referer?
- */
if ((csp->action->flags & ACTION_HIDE_REFERER) == 0)
{
+ /* Nothing left to do */
return JB_ERR_OK;
}
- newval = csp->action->string[ACTION_STRING_REFERER];
+ parameter = csp->action->string[ACTION_STRING_REFERER];
+ assert(parameter != NULL);
+ parameter_conditional_block = (0 == strcmpic(parameter, "conditional-block"));
+ parameter_conditional_forge = (0 == strcmpic(parameter, "conditional-forge"));
- if ((0 != strcmpic(newval, "conditional-block")))
- {
- freez(*header);
- }
- if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
+ if (!parameter_conditional_block && !parameter_conditional_forge)
{
/*
- * Blocking referer
+ * As conditional-block and conditional-forge are the only
+ * parameters that rely on the original referrer, we can
+ * remove it now for all the others.
*/
+ freez(*header);
+ }
+
+ if (0 == strcmpic(parameter, "block"))
+ {
log_error(LOG_LEVEL_HEADER, "Referer crunched!");
return JB_ERR_OK;
}
- else if (0 == strcmpic(newval, "conditional-block"))
+ else if (parameter_conditional_block || parameter_conditional_forge)
{
- /*
- * Block referer if host has changed.
- */
-
- if (NULL == (host = strdup(csp->http->hostport)))
- {
- freez(*header);
- log_error(LOG_LEVEL_HEADER, "Referer crunched! Couldn't allocate memory for temporary host copy.");
- return JB_ERR_MEMORY;
- }
- if (NULL == (referer = strdup(*header)))
- {
- freez(*header);
- freez(host);
- log_error(LOG_LEVEL_HEADER, "Referer crunched! Couldn't allocate memory for temporary referer copy.");
- return JB_ERR_MEMORY;
- }
- hostlenght = strlen(host);
- if ( hostlenght < (strlen(referer)-17) ) /*referer begins with 'Referer: http[s]://'*/
- {
- /*Shorten referer to make sure the referer is blocked
- *if www.example.org/www.example.com-shall-see-the-referer/
- *links to www.example.com/
- */
- referer[hostlenght+17] = '\0';
- }
- if ( 0 == strstr(referer, host)) /*Host has changed*/
- {
- log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
- freez(*header);
- }
- else
- {
- log_error(LOG_LEVEL_HEADER, "%s (not modified, still on %s)", *header, host);
- }
- freez(referer);
- freez(host);
- return JB_ERR_OK;
+ return handle_conditional_hide_referrer_parameter(header,
+ csp->http->hostport, parameter_conditional_block);
}
- else if (0 != strcmpic(newval, "forge"))
+ else if (0 == strcmpic(parameter, "forge"))
{
- /*
- * We have a specific (fixed) referer we want to send.
- */
- if ((0 != strncmpic(newval, "http://", 7)) && (0 != strncmpic(newval, "https://", 8)))
- {
- log_error(LOG_LEVEL_HEADER, "Parameter: +referrer{%s} is a bad idea, but I don't care.", newval);
- }
- *header = strdup("Referer: ");
- string_append(header, newval);
- log_error(LOG_LEVEL_HEADER, "Referer overwritten with: %s", *header);
-
- return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
+ return create_forged_referrer(header, csp->http->hostport);
}
else
{
- /*
- * Forge a referer as http://[hostname:port of REQUEST]/
- * to fool stupid checks for in-site links
- */
-
- *header = strdup("Referer: http://");
- string_append(header, csp->http->hostport);
- string_append(header, "/");
- log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
-
- return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
+ /* interpret parameter as user-supplied referer to fake */
+ return create_fake_referrer(header, parameter);
}
}
+
/*********************************************************************
*
* Function : client_accept_language
return err;
}
+
#if 0
/*********************************************************************
*
}
#endif
+
/*********************************************************************
*
* Function : client_xtra_adder
*********************************************************************/
static jb_err server_http(struct client_state *csp, char **header)
{
- /* XXX: Doesn't belong here. */
sscanf(*header, "HTTP/%*d.%*d %d", &(csp->http->status));
if (csp->http->status == 206)
{
}
+/*********************************************************************
+ *
+ * Function : create_forged_referrer
+ *
+ * Description : Helper for client_referrer to forge a referer as
+ * 'http://[hostname:port/' to fool stupid
+ * checks for in-site links
+ *
+ * Parameters :
+ * 1 : header = Pointer to header pointer
+ * 2 : hostport = Host and optionally port as string
+ *
+ * Returns : JB_ERR_OK in case of success, or
+ * JB_ERR_MEMORY in case of memory problems.
+ *
+ *********************************************************************/
+static jb_err create_forged_referrer(char **header, const char *hostport)
+{
+ assert(NULL == *header);
+
+ *header = strdup("Referer: http://");
+ string_append(header, hostport);
+ string_append(header, "/");
+
+ if (NULL == *header)
+ {
+ return JB_ERR_MEMORY;
+ }
+
+ log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
+
+ return JB_ERR_OK;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : create_fake_referrer
+ *
+ * Description : Helper for client_referrer to create a fake referrer
+ * based on a string supplied by the user.
+ *
+ * Parameters :
+ * 1 : header = Pointer to header pointer
+ * 2 : hosthost = Referrer to fake
+ *
+ * Returns : JB_ERR_OK in case of success, or
+ * JB_ERR_MEMORY in case of memory problems.
+ *
+ *********************************************************************/
+static jb_err create_fake_referrer(char **header, const char *fake_referrer)
+{
+ assert(NULL == *header);
+
+ if ((0 != strncmpic(fake_referrer, "http://", 7)) && (0 != strncmpic(fake_referrer, "https://", 8)))
+ {
+ log_error(LOG_LEVEL_HEADER,
+ "Parameter: +hide-referrer{%s} is a bad idea, but I don't care.", fake_referrer);
+ }
+ *header = strdup("Referer: ");
+ string_append(header, fake_referrer);
+
+ if (NULL == *header)
+ {
+ return JB_ERR_MEMORY;
+ }
+
+ log_error(LOG_LEVEL_HEADER, "Referer replaced with: %s", *header);
+
+ return JB_ERR_OK;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : handle_conditional_hide_referrer_parameter
+ *
+ * Description : Helper for client_referrer to crunch or forge
+ * the referrer header if the host has changed.
+ *
+ * Parameters :
+ * 1 : header = Pointer to header pointer
+ * 2 : host = The target host (may include the port)
+ * 3 : parameter_conditional_block = Boolean to signal
+ * if we're in conditional-block mode. If not set,
+ * we're in conditional-forge mode.
+ *
+ * Returns : JB_ERR_OK in case of success, or
+ * JB_ERR_MEMORY in case of memory problems.
+ *
+ *********************************************************************/
+static jb_err handle_conditional_hide_referrer_parameter(char **header,
+ const char *host, const int parameter_conditional_block)
+{
+ char *referer = strdup(*header);
+ const size_t hostlenght = strlen(host);
+
+ if (NULL == referer)
+ {
+ freez(*header);
+ return JB_ERR_MEMORY;
+ }
+
+ /* referer begins with 'Referer: http[s]://' */
+ if (hostlenght < (strlen(referer)-17))
+ {
+ /*
+ * Shorten referer to make sure the referer is blocked
+ * if www.example.org/www.example.com-shall-see-the-referer/
+ * links to www.example.com/
+ */
+ referer[hostlenght+17] = '\0';
+ }
+ if (NULL == strstr(referer, host))
+ {
+ /* Host has changed */
+ if (parameter_conditional_block)
+ {
+ log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
+ freez(*header);
+ }
+ else
+ {
+ freez(*header);
+ freez(referer);
+ return create_forged_referrer(header, host);
+ }
+ }
+ freez(referer);
+
+ return JB_ERR_OK;
+
+}
+
/*
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projects / privoxy.git / blobdiff