Implemented a hook to inject custom proposals

src/conftest/Makefile.am

@@ -8,7 +8,7 @@ conftest_SOURCES = conftest.c conftest.h config.c config.h actions.c actions.h \
 	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/set_proposal_number.c hooks/log_ke.c \
-	hooks/log_id.c
+	hooks/log_id.c hooks/custom_proposal.c
 
 INCLUDES = \
 	-I$(top_srcdir)/src/libstrongswan \

src/conftest/hooks/custom_proposal.c

@@ -0,0 +1,188 @@
+/*
+ * 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 <errno.h>
+
+#include <encoding/payloads/sa_payload.h>
+#include <config/proposal.h>
+#include <crypto/proposal/proposal_keywords.h>
+
+typedef struct private_custom_proposal_t private_custom_proposal_t;
+
+/**
+ * Private data of an custom_proposal_t object.
+ */
+struct private_custom_proposal_t {
+
+	/**
+	 * Implements the hook_t interface.
+	 */
+	hook_t hook;
+
+	/**
+	 * Alter requests or responses?
+	 */
+	bool req;
+
+	/**
+	 * ID of message to alter.
+	 */
+	int id;
+
+	/**
+	 * hook name
+	 */
+	char *name;
+};
+
+/**
+ * Load custom proposal configuration to proposal list
+ */
+static linked_list_t* load_proposals(private_custom_proposal_t *this,
+									 protocol_id_t proto, u_int64_t spi)
+{
+	enumerator_t *props, *algs;
+	char *number, *key, *value;
+	linked_list_t *list;
+
+	list = linked_list_create();
+	props = conftest->test->create_section_enumerator(conftest->test,
+													  "hooks.%s", this->name);
+	while (props->enumerate(props, &number))
+	{
+		const proposal_token_t *token = NULL;
+		proposal_t *proposal;
+		u_int16_t type, alg, keysize = 0;
+		char *end;
+
+		proposal = proposal_create(proto, atoi(number));
+		proposal->set_spi(proposal, spi);
+
+		algs = conftest->test->create_key_value_enumerator(conftest->test,
+											"hooks.%s.%s", this->name, number);
+		while (algs->enumerate(algs, &key, &value))
+		{
+			errno = 0;
+			type = strtoul(key, &end, 10);
+			if (end == key || errno)
+			{
+				type = enum_from_name(transform_type_names, key);
+				if (type == -1)
+				{
+					DBG1(DBG_CFG, "unknown transform: '%s', skipped", key);
+					continue;
+				}
+			}
+			errno = 0;
+			alg = strtoul(value, &end, 10);
+			if (end == value || errno)
+			{
+				token = proposal_get_token(value, strlen(value));
+				if (!token)
+				{
+					DBG1(DBG_CFG, "unknown algorithm: '%s', skipped", value);
+					continue;
+				}
+				keysize = token->keysize;
+				alg = token->algorithm;
+			}
+			proposal->add_algorithm(proposal, type, alg, keysize);
+		}
+		algs->destroy(algs);
+		list->insert_last(list, proposal);
+	}
+	props->destroy(props);
+	return list;
+}
+
+METHOD(listener_t, message, bool,
+	private_custom_proposal_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;
+		sa_payload_t *new, *old = NULL;
+		linked_list_t *new_props, *old_props;
+		proposal_t *proposal;
+
+		enumerator = message->create_payload_enumerator(message);
+		while (enumerator->enumerate(enumerator, &payload))
+		{
+			if (payload->get_type(payload) == SECURITY_ASSOCIATION)
+			{
+				old = (sa_payload_t*)payload;
+				message->remove_payload_at(message, enumerator);
+			}
+		}
+		enumerator->destroy(enumerator);
+
+		if (old)
+		{
+			old_props = old->get_proposals(old);
+			old->destroy(old);
+			enumerator = old_props->create_enumerator(old_props);
+			if (enumerator->enumerate(enumerator, &proposal))
+			{
+				new_props = load_proposals(this,
+										   proposal->get_protocol(proposal),
+										   proposal->get_spi(proposal));
+				DBG1(DBG_CFG, "injecting custom proposal: %#P", new_props);
+				new = sa_payload_create_from_proposal_list(new_props);
+				message->add_payload(message, (payload_t*)new);
+				new_props->destroy_offset(new_props, offsetof(proposal_t, destroy));
+			}
+			enumerator->destroy(enumerator);
+			old_props->destroy_offset(old_props, offsetof(proposal_t, destroy));
+		}
+	}
+	return TRUE;
+}
+
+METHOD(hook_t, destroy, void,
+	private_custom_proposal_t *this)
+{
+	free(this->name);
+	free(this);
+}
+
+/**
+ * Create the IKE_AUTH fill hook
+ */
+hook_t *custom_proposal_hook_create(char *name)
+{
+	private_custom_proposal_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),
+		.name = strdup(name),
+	);
+
+	return &this->hook;
+}