Added a hook to modify proposal numbers

2011-01-05 16:45:47 +01:00
parent 5dca645d46
commit 6dd6b0ef95
2 changed files with 164 additions and 1 deletions
@@ -7,7 +7,7 @@ conftest_SOURCES = conftest.c conftest.h config.c config.h actions.c actions.h \
 	hooks/add_notify.c hooks/unencrypted_notify.c hooks/ignore_message.c \
 	hooks/add_payload.c hooks/set_critical.c hooks/force_cookie.c \
 	hooks/set_ike_version.c hooks/pretend_auth.c hooks/set_length.c \
-	hooks/log_proposals.c
+	hooks/log_proposals.c hooks/set_proposal_number.c

 INCLUDES = \
 	-I$(top_srcdir)/src/libstrongswan \
@@ -0,0 +1,163 @@
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Copyright (C) 2010 revosec AG
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "hook.h"
+
+#include <encoding/payloads/sa_payload.h>
+
+typedef struct private_set_proposal_number_t private_set_proposal_number_t;
+
+/**
+ * Private data of an set_proposal_number_t object.
+ */
+struct private_set_proposal_number_t {
+
+	/**
+	 * Implements the hook_t interface.
+	 */
+	hook_t hook;
+
+	/**
+	 * Alter requests or responses?
+	 */
+	bool req;
+
+	/**
+	 * ID of message to alter.
+	 */
+	int id;
+
+	/**
+	 * Proposal number to modify
+	 */
+	int from;
+
+	/**
+	 * Proposal number to set
+	 */
+	int to;
+};
+
+/**
+ * Copy all algs from given type from one proposal to another
+ */
+static void copy_proposal_algs(proposal_t *from, proposal_t *to,
+							   transform_type_t type)
+{
+	enumerator_t *enumerator;
+	u_int16_t alg, key_size;
+
+	enumerator = from->create_enumerator(from, type);
+	while (enumerator->enumerate(enumerator, &alg, &key_size))
+	{
+		to->add_algorithm(to, type, alg, key_size);
+	}
+	enumerator->destroy(enumerator);
+}
+
+METHOD(listener_t, message, bool,
+	private_set_proposal_number_t *this, ike_sa_t *ike_sa, message_t *message,
+	bool incoming)
+{
+	if (!incoming &&
+		message->get_request(message) == this->req &&
+		message->get_message_id(message) == this->id)
+	{
+		enumerator_t *enumerator;
+		payload_t *payload;
+		linked_list_t *list = NULL, *updated;
+		sa_payload_t *sa;
+		proposal_t *proposal, *new;
+
+		updated = linked_list_create();
+		enumerator = message->create_payload_enumerator(message);
+		while (enumerator->enumerate(enumerator, &payload))
+		{
+			if (payload->get_type(payload) == SECURITY_ASSOCIATION)
+			{
+				sa = (sa_payload_t*)payload;
+				list = sa->get_proposals(sa);
+				message->remove_payload_at(message, enumerator);
+				sa->destroy(sa);
+			}
+		}
+		enumerator->destroy(enumerator);
+
+		if (list)
+		{
+			enumerator = list->create_enumerator(list);
+			while (enumerator->enumerate(enumerator, &proposal))
+			{
+				if (proposal->get_number(proposal) == this->from)
+				{
+					DBG1(DBG_CFG, "setting proposal number from %d to %d",
+						 this->from, this->to);
+					new = proposal_create(proposal->get_protocol(proposal),
+										  this->to);
+					copy_proposal_algs(proposal, new, ENCRYPTION_ALGORITHM);
+					copy_proposal_algs(proposal, new, INTEGRITY_ALGORITHM);
+					copy_proposal_algs(proposal, new, PSEUDO_RANDOM_FUNCTION);
+					copy_proposal_algs(proposal, new, DIFFIE_HELLMAN_GROUP);
+					copy_proposal_algs(proposal, new, EXTENDED_SEQUENCE_NUMBERS);
+					updated->insert_last(updated, new);
+				}
+				else
+				{
+					list->remove_at(list, enumerator);
+					updated->insert_last(updated, proposal);
+				}
+			}
+			enumerator->destroy(enumerator);
+		}
+		sa = sa_payload_create_from_proposal_list(updated);
+		list->destroy_offset(list, offsetof(proposal_t, destroy));
+		updated->destroy_offset(updated, offsetof(proposal_t, destroy));
+		message->add_payload(message, (payload_t*)sa);
+	}
+	return TRUE;
+}
+
+METHOD(hook_t, destroy, void,
+	private_set_proposal_number_t *this)
+{
+	free(this);
+}
+
+/**
+ * Create the IKE_AUTH fill hook
+ */
+hook_t *set_proposal_number_hook_create(char *name)
+{
+	private_set_proposal_number_t *this;
+
+	INIT(this,
+		.hook = {
+			.listener = {
+				.message = _message,
+			},
+			.destroy = _destroy,
+		},
+		.req = conftest->test->get_bool(conftest->test,
+										"hooks.%s.request", TRUE, name),
+		.id = conftest->test->get_int(conftest->test,
+										"hooks.%s.id", 0, name),
+		.from = conftest->test->get_int(conftest->test,
+										"hooks.%s.from", 0, name),
+		.to = conftest->test->get_int(conftest->test,
+										"hooks.%s.to", 1, name),
+	);
+
+	return &this->hook;
+}