ha: Add support to sync IKE and Child SAs with multiple key exchanges

Synchronization for the additional transforms in the IKE and Child SA proposals is added. Details of the IKE_SA synchronization are changed to support IKE_INTERMEDIATE exchanges that cause multiple HA_IKE_ADD messages and key derivations. The cache has been extended to handle multiple such messages. Co-authored-by: Thomas Egerer <[email protected]>
2025-02-28 16:02:41 +01:00
parent f717bb5249
commit e7848e36fa
8 changed files with 263 additions and 121 deletions
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2015-2024 Tobias Brunner
 * Copyright (C) 2010 Martin Willi
 *
 * Copyright (C) secunet Security Networks AG
@@ -70,9 +71,9 @@ struct private_ha_cache_t {
 typedef struct {
 	/* segment this entry is associate to */
 	u_int segment;
-	/* ADD message */
-	ha_message_t *add;
-	/* list of updates UPDATE message */
+	/* list of ADD messages */
+	linked_list_t *add;
+	/* list of UPDATE messages */
 	linked_list_t *updates;
 	/* last initiator mid */
 	ha_message_t *midi;
@@ -83,27 +84,27 @@ typedef struct {
 } entry_t;

 /**
- * Create a entry with an add message
+ * Create a entry
 */
-static entry_t *entry_create(ha_message_t *add)
+static entry_t *entry_create()
 {
 	entry_t *entry;

 	INIT(entry,
-		.add = add,
+		.add = linked_list_create(),
 		.updates = linked_list_create(),
 	);
 	return entry;
 }

 /**
- * clean up a entry
+ * Clean up a entry
 */
 static void entry_destroy(entry_t *entry)
 {
 	entry->updates->destroy_offset(entry->updates,
-									offsetof(ha_message_t, destroy));
-	entry->add->destroy(entry->add);
+								   offsetof(ha_message_t, destroy));
+	entry->add->destroy_offset(entry->add, offsetof(ha_message_t, destroy));
 	DESTROY_IF(entry->midi);
 	DESTROY_IF(entry->midr);
 	DESTROY_IF(entry->iv);
@@ -119,12 +120,13 @@ METHOD(ha_cache_t, cache, void,
 	switch (message->get_type(message))
 	{
 		case HA_IKE_ADD:
-			entry = entry_create(message);
-			entry = this->cache->put(this->cache, ike_sa, entry);
-			if (entry)
+			entry = this->cache->get(this->cache, ike_sa);
+			if (!entry)
 			{
-				entry_destroy(entry);
+				entry = entry_create();
+				this->cache->put(this->cache, ike_sa, entry);
 			}
+			entry->add->insert_last(entry->add, message);
 			break;
 		case HA_IKE_UPDATE:
 			entry = this->cache->get(this->cache, ike_sa);
@@ -305,7 +307,7 @@ static void rekey_segment(private_ha_cache_t *this, u_int segment)
 METHOD(ha_cache_t, resync, void,
 	private_ha_cache_t *this, u_int segment)
 {
-	enumerator_t *enumerator, *updates;
+	enumerator_t *enumerator, *messages;
 	ike_sa_t *ike_sa;
 	entry_t *entry;
 	ha_message_t *message;
@@ -318,13 +320,18 @@ METHOD(ha_cache_t, resync, void,
 	{
 		if (entry->segment == segment)
 		{
-			this->socket->push(this->socket, entry->add);
-			updates = entry->updates->create_enumerator(entry->updates);
-			while (updates->enumerate(updates, &message))
+			messages = entry->add->create_enumerator(entry->add);
+			while (messages->enumerate(messages, &message))
 			{
 				this->socket->push(this->socket, message);
 			}
-			updates->destroy(updates);
+			messages->destroy(messages);
+			messages = entry->updates->create_enumerator(entry->updates);
+			while (messages->enumerate(messages, &message))
+			{
+				this->socket->push(this->socket, message);
+			}
+			messages->destroy(messages);
 			if (entry->midi)
 			{
 				this->socket->push(this->socket, entry->midi);
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2024 Tobias Brunner
 * Copyright (C) 2008 Martin Willi
 *
 * Copyright (C) secunet Security Networks AG
@@ -91,21 +92,23 @@ METHOD(listener_t, child_keys, bool,
 	{
 		m->add_attribute(m, HA_ALG_INTEG, alg);
 	}
-	if (proposal->get_algorithm(proposal, KEY_EXCHANGE_METHOD, &alg, NULL))
-	{
-		m->add_attribute(m, HA_ALG_DH, alg);
-	}
+	m->add_key_exchange_methods(m, proposal);
 	if (proposal->get_algorithm(proposal, EXTENDED_SEQUENCE_NUMBERS, &alg, NULL))
 	{
 		m->add_attribute(m, HA_ESN, alg);
 	}
+
 	m->add_attribute(m, HA_NONCE_I, nonce_i);
 	m->add_attribute(m, HA_NONCE_R, nonce_r);
 	if (kes && key_exchange_concat_secrets(kes, &secret, &add_secret))
 	{
 		m->add_attribute(m, HA_SECRET, secret);
 		chunk_clear(&secret);
-		chunk_clear(&add_secret);
+		if (add_secret.len)
+		{
+			m->add_attribute(m, HA_ADD_SECRET, add_secret);
+			chunk_clear(&add_secret);
+		}
 	}

 	local_ts = linked_list_create();
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2016-2024 Tobias Brunner
 * Copyright (C) 2008 Martin Willi
 *
 * Copyright (C) secunet Security Networks AG
@@ -23,7 +24,7 @@
 #include <processing/jobs/adopt_children_job.h>

 typedef struct private_ha_dispatcher_t private_ha_dispatcher_t;
-typedef struct ha_diffie_hellman_t ha_diffie_hellman_t;
+typedef struct ha_key_exchange_t ha_key_exchange_t;

 /**
 * Private data of an ha_dispatcher_t object.
@@ -62,14 +63,14 @@ struct private_ha_dispatcher_t {
 };

 /**
- * DH implementation for HA synced DH values
+ * KE implementation for HA synced KE shared secrets
 */
-struct ha_diffie_hellman_t {
+struct ha_key_exchange_t {

 	/**
-	 * Implements key_exchange_t
+	 * Public interface
 	 */
-	key_exchange_t dh;
+	key_exchange_t ke;

 	/**
 	 * Shared secret
@@ -77,49 +78,73 @@ struct ha_diffie_hellman_t {
 	chunk_t secret;

 	/**
-	 * Own public value
+	 * Own public value (IKEv1 only)
 	 */
 	chunk_t pub;
 };

-METHOD(key_exchange_t, dh_get_shared_secret, bool,
-	ha_diffie_hellman_t *this, chunk_t *secret)
+METHOD(key_exchange_t, ke_get_shared_secret, bool,
+	ha_key_exchange_t *this, chunk_t *secret)
 {
 	*secret = chunk_clone(this->secret);
 	return TRUE;
 }

-METHOD(key_exchange_t, dh_get_public_key, bool,
-	ha_diffie_hellman_t *this, chunk_t *value)
+METHOD(key_exchange_t, ke_get_public_key, bool,
+	ha_key_exchange_t *this, chunk_t *value)
 {
 	*value = chunk_clone(this->pub);
 	return TRUE;
 }

-METHOD(key_exchange_t, dh_destroy, void,
-	ha_diffie_hellman_t *this)
+METHOD(key_exchange_t, ke_destroy, void,
+	ha_key_exchange_t *this)
 {
 	free(this);
 }

 /**
- * Create a HA synced DH implementation
+ * Create a HA synced KE implementation
 */
-static key_exchange_t *ha_diffie_hellman_create(chunk_t secret, chunk_t pub)
+static key_exchange_t *ha_key_exchange_create(chunk_t secret, chunk_t pub)
 {
-	ha_diffie_hellman_t *this;
+	ha_key_exchange_t *this;

 	INIT(this,
-		.dh = {
-			.get_shared_secret = _dh_get_shared_secret,
-			.get_public_key = _dh_get_public_key,
-			.destroy = _dh_destroy,
+		.ke = {
+			.get_shared_secret = _ke_get_shared_secret,
+			.get_public_key = _ke_get_public_key,
+			.destroy = _ke_destroy,
 		},
 		.secret = secret,
 		.pub = pub,
 	);

-	return &this->dh;
+	return &this->ke;
+}
+
+/**
+ * Add the given KE methods to a proposal
+ */
+static void add_ke_methods_to_proposal(proposal_t *proposal, uint16_t ke_alg,
+									   chunk_t add_kes)
+{
+	int i, count;
+
+	if (ke_alg)
+	{
+		proposal->add_algorithm(proposal, KEY_EXCHANGE_METHOD, ke_alg, 0);
+	}
+	count = min(add_kes.len / sizeof(uint16_t), MAX_ADDITIONAL_KEY_EXCHANGES);
+	for (i = 0; i < count; i++)
+	{
+		ke_alg = ntohs(((uint16_t*)add_kes.ptr)[i]);
+		if (ke_alg)
+		{
+			proposal->add_algorithm(proposal, i + ADDITIONAL_KEY_EXCHANGE_1,
+									ke_alg, 0);
+		}
+	}
 }

 /**
@@ -133,9 +158,10 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 	ike_sa_t *ike_sa = NULL, *old_sa = NULL;
 	ike_version_t version = IKEV2;
 	uint16_t encr = 0, len = 0, integ = 0, prf = 0, old_prf = PRF_UNDEFINED;
-	uint16_t dh_grp = 0;
+	uint16_t ke_alg = 0;
 	chunk_t nonce_i = chunk_empty, nonce_r = chunk_empty;
 	chunk_t secret = chunk_empty, old_skd = chunk_empty;
+	chunk_t add_secret = chunk_empty, add_kes = chunk_empty;
 	chunk_t dh_local = chunk_empty, dh_remote = chunk_empty, psk = chunk_empty;
 	host_t *other = NULL;
 	bool ok = FALSE;
@@ -147,8 +173,13 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 		switch (attribute)
 		{
 			case HA_IKE_ID:
-				ike_sa = ike_sa_create(value.ike_sa_id,
+				ike_sa = charon->ike_sa_manager->checkout(charon->ike_sa_manager,
+														  value.ike_sa_id);
+				if (!ike_sa)
+				{
+					ike_sa = ike_sa_create(value.ike_sa_id,
 						value.ike_sa_id->is_initiator(value.ike_sa_id), version);
+				}
 				break;
 			case HA_IKE_REKEY_ID:
 				old_sa = charon->ike_sa_manager->checkout(charon->ike_sa_manager,
@@ -169,6 +200,9 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 			case HA_SECRET:
 				secret = value.chunk;
 				break;
+			case HA_ADD_SECRET:
+				add_secret = value.chunk;
+				break;
 			case HA_LOCAL_DH:
 				dh_local = value.chunk;
 				break;
@@ -196,11 +230,15 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 			case HA_ALG_OLD_PRF:
 				old_prf = value.u16;
 				break;
-			case HA_ALG_DH:
-				dh_grp = value.u16;
+			case HA_ALG_KE:
+				ke_alg = value.u16;
+				break;
+			case HA_ALG_ADD_KES:
+				add_kes = value.chunk;
 				break;
 			case HA_AUTH_METHOD:
 				method = value.u16;
+				break;
 			default:
 				break;
 		}
@@ -210,38 +248,52 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 	if (ike_sa)
 	{
 		proposal_t *proposal;
-		key_exchange_t *dh;
+		key_exchange_t *ke;
+		array_t *kes = NULL;
+		bool key_update = FALSE;

-		proposal = proposal_create(PROTO_IKE, 0);
-		if (integ)
+		proposal = ike_sa->get_proposal(ike_sa);
+		if (!proposal)
 		{
-			proposal->add_algorithm(proposal, INTEGRITY_ALGORITHM, integ, 0);
+			proposal = proposal_create(PROTO_IKE, 0);
+			if (integ)
+			{
+				proposal->add_algorithm(proposal, INTEGRITY_ALGORITHM, integ, 0);
+			}
+			if (encr)
+			{
+				proposal->add_algorithm(proposal, ENCRYPTION_ALGORITHM, encr, len);
+			}
+			if (prf)
+			{
+				proposal->add_algorithm(proposal, PSEUDO_RANDOM_FUNCTION, prf, 0);
+			}
+			add_ke_methods_to_proposal(proposal, ke_alg, add_kes);
 		}
-		if (encr)
+		else
 		{
-			proposal->add_algorithm(proposal, ENCRYPTION_ALGORITHM, encr, len);
-		}
-		if (prf)
-		{
-			proposal->add_algorithm(proposal, PSEUDO_RANDOM_FUNCTION, prf, 0);
-		}
-		if (dh_grp)
-		{
-			proposal->add_algorithm(proposal, KEY_EXCHANGE_METHOD, dh_grp, 0);
+			key_update = TRUE;
 		}
 		charon->bus->set_sa(charon->bus, ike_sa);
-		dh = ha_diffie_hellman_create(secret, dh_local);
+		ke = ha_key_exchange_create(secret, dh_local);
+		array_insert_create(&kes, ARRAY_HEAD, ke);
 		if (ike_sa->get_version(ike_sa) == IKEV2)
 		{
 			keymat_v2_t *keymat_v2 = (keymat_v2_t*)ike_sa->get_keymat(ike_sa);
-			array_t *kes = NULL;

-			array_insert_create(&kes, ARRAY_HEAD, dh);
+			if (add_secret.len)
+			{
+				ke = ha_key_exchange_create(add_secret, chunk_empty);
+				array_insert_create(&kes, ARRAY_TAIL, ke);
+			}
+			if (key_update)
+			{
+				old_prf = keymat_v2->get_skd(keymat_v2, &old_skd);
+			}
 			ok = keymat_v2->derive_ike_keys(keymat_v2, proposal, kes, nonce_i,
 							nonce_r, ike_sa->get_id(ike_sa), old_prf, old_skd);
-			array_destroy(kes);
 		}
-		if (ike_sa->get_version(ike_sa) == IKEV1)
+		else if (ike_sa->get_version(ike_sa) == IKEV1)
 		{
 			keymat_v1_t *keymat_v1 = (keymat_v1_t*)ike_sa->get_keymat(ike_sa);
 			shared_key_t *shared = NULL;
@@ -254,12 +306,12 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 			if (keymat_v1->create_hasher(keymat_v1, proposal))
 			{
 				ok = keymat_v1->derive_ike_keys(keymat_v1, proposal,
-								dh, dh_remote, nonce_i, nonce_r,
+								ke, dh_remote, nonce_i, nonce_r,
 								ike_sa->get_id(ike_sa), method, shared);
 			}
 			DESTROY_IF(shared);
 		}
-		dh->destroy(dh);
+		array_destroy_offset(kes, offsetof(key_exchange_t, destroy));
 		if (ok)
 		{
 			if (old_sa)
@@ -278,8 +330,11 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 				ike_sa->set_other_host(ike_sa, other);
 				other = NULL;
 			}
-			ike_sa->set_state(ike_sa, IKE_CONNECTING);
-			ike_sa->set_proposal(ike_sa, proposal);
+			if (!key_update)
+			{
+				ike_sa->set_state(ike_sa, IKE_CONNECTING);
+				ike_sa->set_proposal(ike_sa, proposal);
+			}
 			this->cache->cache(this->cache, ike_sa, message);
 			message = NULL;
 			charon->ike_sa_manager->checkin(charon->ike_sa_manager, ike_sa);
@@ -287,10 +342,21 @@ static void process_ike_add(private_ha_dispatcher_t *this, ha_message_t *message
 		else
 		{
 			DBG1(DBG_IKE, "HA keymat derivation failed");
-			ike_sa->destroy(ike_sa);
+			if (key_update)
+			{
+				charon->ike_sa_manager->checkin_and_destroy(charon->ike_sa_manager,
+															ike_sa);
+			}
+			else
+			{
+				ike_sa->destroy(ike_sa);
+				charon->bus->set_sa(charon->bus, NULL);
+			}
+		}
+		if (!key_update)
+		{
+			proposal->destroy(proposal);
 		}
-		charon->bus->set_sa(charon->bus, NULL);
-		proposal->destroy(proposal);
 	}
 	if (old_sa)
 	{
@@ -659,12 +725,13 @@ static void process_child_add(private_ha_dispatcher_t *this,
 	uint32_t inbound_spi = 0, outbound_spi = 0;
 	uint16_t inbound_cpi = 0, outbound_cpi = 0;
 	uint8_t mode = MODE_TUNNEL, ipcomp = 0;
-	uint16_t encr = 0, integ = 0, len = 0, dh_grp = 0;
+	uint16_t encr = 0, integ = 0, len = 0, ke_alg = 0;
 	uint16_t esn = NO_EXT_SEQ_NUMBERS;
 	chunk_t nonce_i = chunk_empty, nonce_r = chunk_empty, secret = chunk_empty;
+	chunk_t add_secret = chunk_empty, add_kes = chunk_empty;
 	chunk_t encr_i, integ_i, encr_r, integ_r;
 	linked_list_t *local_ts, *remote_ts;
-	key_exchange_t *dh = NULL;
+	key_exchange_t *ke = NULL;
 	array_t *kes = NULL;

 	enumerator = message->create_attribute_enumerator(message);
@@ -709,8 +776,11 @@ static void process_child_add(private_ha_dispatcher_t *this,
 			case HA_ALG_INTEG:
 				integ = value.u16;
 				break;
-			case HA_ALG_DH:
-				dh_grp = value.u16;
+			case HA_ALG_KE:
+				ke_alg = value.u16;
+				break;
+			case HA_ALG_ADD_KES:
+				add_kes = value.chunk;
 				break;
 			case HA_ESN:
 				esn = value.u16;
@@ -724,6 +794,9 @@ static void process_child_add(private_ha_dispatcher_t *this,
 			case HA_SECRET:
 				secret = value.chunk;
 				break;
+			case HA_ADD_SECRET:
+				add_secret = value.chunk;
+				break;
 			default:
 				break;
 		}
@@ -763,15 +836,18 @@ static void process_child_add(private_ha_dispatcher_t *this,
 	{
 		proposal->add_algorithm(proposal, ENCRYPTION_ALGORITHM, encr, len);
 	}
-	if (dh_grp)
-	{
-		proposal->add_algorithm(proposal, KEY_EXCHANGE_METHOD, dh_grp, 0);
-	}
+	add_ke_methods_to_proposal(proposal, ke_alg, add_kes);
 	proposal->add_algorithm(proposal, EXTENDED_SEQUENCE_NUMBERS, esn, 0);
+
 	if (secret.len)
 	{
-		dh = ha_diffie_hellman_create(secret, chunk_empty);
-		array_insert_create(&kes, ARRAY_HEAD, dh);
+		ke = ha_key_exchange_create(secret, chunk_empty);
+		array_insert_create(&kes, ARRAY_HEAD, ke);
+	}
+	if (add_secret.len)
+	{
+		ke = ha_key_exchange_create(add_secret, chunk_empty);
+		array_insert_create(&kes, ARRAY_TAIL, ke);
 	}
 	if (ike_sa->get_version(ike_sa) == IKEV2)
 	{
@@ -780,7 +856,7 @@ static void process_child_add(private_ha_dispatcher_t *this,
 		ok = keymat_v2->derive_child_keys(keymat_v2, proposal, kes,
 						nonce_i, nonce_r, &encr_i, &integ_i, &encr_r, &integ_r);
 	}
-	if (ike_sa->get_version(ike_sa) == IKEV1)
+	else if (ike_sa->get_version(ike_sa) == IKEV1)
 	{
 		keymat_v1_t *keymat_v1 = (keymat_v1_t*)ike_sa->get_keymat(ike_sa);
 		uint32_t spi_i, spi_r;
@@ -788,11 +864,10 @@ static void process_child_add(private_ha_dispatcher_t *this,
 		spi_i = initiator ? inbound_spi : outbound_spi;
 		spi_r = initiator ? outbound_spi : inbound_spi;

-		ok = keymat_v1->derive_child_keys(keymat_v1, proposal, dh, spi_i, spi_r,
+		ok = keymat_v1->derive_child_keys(keymat_v1, proposal, ke, spi_i, spi_r,
 						nonce_i, nonce_r, &encr_i, &integ_i, &encr_r, &integ_r);
 	}
-	array_destroy(kes);
-	DESTROY_IF(dh);
+	array_destroy_offset(kes, offsetof(key_exchange_t, destroy));
 	if (!ok)
 	{
 		DBG1(DBG_CHD, "HA CHILD_SA key derivation failed");
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2024 Tobias Brunner
 * Copyright (C) 2008 Martin Willi
 *
 * Copyright (C) secunet Security Networks AG
@@ -97,8 +98,7 @@ METHOD(listener_t, ike_keys, bool,
 		return TRUE;
 	}
 	if (!key_exchange_concat_secrets(kes, &secret, &add_secret) ||
-		!array_get(kes, ARRAY_HEAD, &ke) ||
-		add_secret.len > 0)
+		!array_get(kes, ARRAY_HEAD, &ke))
 	{
 		chunk_clear(&secret);
 		chunk_clear(&add_secret);
@@ -109,7 +109,7 @@ METHOD(listener_t, ike_keys, bool,
 	m->add_attribute(m, HA_IKE_VERSION, ike_sa->get_version(ike_sa));
 	m->add_attribute(m, HA_IKE_ID, ike_sa->get_id(ike_sa));

-	if (rekey && rekey->get_version(rekey) == IKEV2)
+	if (rekey && rekey != ike_sa && rekey->get_version(rekey) == IKEV2)
 	{
 		chunk_t skd;
 		keymat_v2_t *keymat;
@@ -119,32 +119,37 @@ METHOD(listener_t, ike_keys, bool,
 		m->add_attribute(m, HA_ALG_OLD_PRF, keymat->get_skd(keymat, &skd));
 		m->add_attribute(m, HA_OLD_SKD, skd);
 	}
-
-	proposal = ike_sa->get_proposal(ike_sa);
-	if (proposal->get_algorithm(proposal, ENCRYPTION_ALGORITHM, &alg, &len))
+	if (rekey != ike_sa)
 	{
-		m->add_attribute(m, HA_ALG_ENCR, alg);
-		if (len)
+		/* only sync the proposal for initial key derivation and rekeyings */
+		proposal = ike_sa->get_proposal(ike_sa);
+		if (proposal->get_algorithm(proposal, ENCRYPTION_ALGORITHM, &alg, &len))
 		{
-			m->add_attribute(m, HA_ALG_ENCR_LEN, len);
+			m->add_attribute(m, HA_ALG_ENCR, alg);
+			if (len)
+			{
+				m->add_attribute(m, HA_ALG_ENCR_LEN, len);
+			}
 		}
-	}
-	if (proposal->get_algorithm(proposal, INTEGRITY_ALGORITHM, &alg, NULL))
-	{
-		m->add_attribute(m, HA_ALG_INTEG, alg);
-	}
-	if (proposal->get_algorithm(proposal, PSEUDO_RANDOM_FUNCTION, &alg, NULL))
-	{
-		m->add_attribute(m, HA_ALG_PRF, alg);
-	}
-	if (proposal->get_algorithm(proposal, KEY_EXCHANGE_METHOD, &alg, NULL))
-	{
-		m->add_attribute(m, HA_ALG_DH, alg);
+		if (proposal->get_algorithm(proposal, INTEGRITY_ALGORITHM, &alg, NULL))
+		{
+			m->add_attribute(m, HA_ALG_INTEG, alg);
+		}
+		if (proposal->get_algorithm(proposal, PSEUDO_RANDOM_FUNCTION, &alg, NULL))
+		{
+			m->add_attribute(m, HA_ALG_PRF, alg);
+		}
+		m->add_key_exchange_methods(m, proposal);
 	}
 	m->add_attribute(m, HA_NONCE_I, nonce_i);
 	m->add_attribute(m, HA_NONCE_R, nonce_r);
 	m->add_attribute(m, HA_SECRET, secret);
 	chunk_clear(&secret);
+	if (add_secret.len)
+	{
+		m->add_attribute(m, HA_ADD_SECRET, add_secret);
+		chunk_clear(&add_secret);
+	}
 	if (ike_sa->get_version(ike_sa) == IKEV1)
 	{
 		if (ke->get_public_key(ke, &secret))
@@ -421,4 +426,3 @@ ha_ike_t *ha_ike_create(ha_socket_t *socket, ha_tunnel_t *tunnel,

 	return &this->public;
 }
-
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2024 Tobias Brunner
 * Copyright (C) 2008 Martin Willi
 *
 * Copyright (C) secunet Security Networks AG
@@ -231,7 +232,7 @@ METHOD(ha_message_t, add_attribute, void,
 			break;
 		}
 		/* uint16_t */
-		case HA_ALG_DH:
+		case HA_ALG_KE:
 		case HA_ALG_PRF:
 		case HA_ALG_OLD_PRF:
 		case HA_ALG_ENCR:
@@ -270,11 +271,13 @@ METHOD(ha_message_t, add_attribute, void,
 		case HA_NONCE_I:
 		case HA_NONCE_R:
 		case HA_SECRET:
+		case HA_ADD_SECRET:
 		case HA_LOCAL_DH:
 		case HA_REMOTE_DH:
 		case HA_PSK:
 		case HA_IV:
 		case HA_OLD_SKD:
+		case HA_ALG_ADD_KES:
 		{
 			chunk_t chunk;

@@ -318,6 +321,36 @@ METHOD(ha_message_t, add_attribute, void,
 	va_end(args);
 }

+METHOD(ha_message_t, add_key_exchange_methods, void,
+	private_ha_message_t *this, proposal_t *proposal)
+{
+	uint16_t algs[MAX_ADDITIONAL_KEY_EXCHANGES] = {};
+	int i, count = 0;
+
+	if (proposal->get_algorithm(proposal, KEY_EXCHANGE_METHOD, &algs[0], NULL))
+	{
+		add_attribute(this, HA_ALG_KE, algs[0]);
+		algs[0] = 0;
+	}
+	for (i = 0; i < countof(algs); i++)
+	{
+		if (proposal->get_algorithm(proposal, i + ADDITIONAL_KEY_EXCHANGE_1,
+									&algs[i], NULL))
+		{
+			count = i+1;
+		}
+	}
+	if (count)
+	{
+		for (i = 0; i < count; i++)
+		{
+			algs[i] = htons(algs[i]);
+		}
+		add_attribute(this, HA_ALG_ADD_KES,
+					  chunk_create((u_char*)algs, count * sizeof(uint16_t)));
+	}
+}
+
 /**
 * Attribute enumerator implementation
 */
@@ -455,7 +488,7 @@ METHOD(enumerator_t, attribute_enumerate, bool,
 			return TRUE;
 		}
 		/** uint16_t */
-		case HA_ALG_DH:
+		case HA_ALG_KE:
 		case HA_ALG_PRF:
 		case HA_ALG_OLD_PRF:
 		case HA_ALG_ENCR:
@@ -496,11 +529,13 @@ METHOD(enumerator_t, attribute_enumerate, bool,
 		case HA_NONCE_I:
 		case HA_NONCE_R:
 		case HA_SECRET:
+		case HA_ADD_SECRET:
 		case HA_LOCAL_DH:
 		case HA_REMOTE_DH:
 		case HA_PSK:
 		case HA_IV:
 		case HA_OLD_SKD:
+		case HA_ALG_ADD_KES:
 		{
 			size_t len;

@@ -626,7 +661,7 @@ METHOD(ha_message_t, get_encoding, chunk_t,
 METHOD(ha_message_t, destroy, void,
 	private_ha_message_t *this)
 {
-	free(this->buf.ptr);
+	chunk_clear(&this->buf);
 	free(this);
 }

@@ -639,6 +674,7 @@ static private_ha_message_t *ha_message_create_generic()
 		.public = {
 			.get_type = _get_type,
 			.add_attribute = _add_attribute,
+			.add_key_exchange_methods = _add_key_exchange_methods,
 			.create_attribute_enumerator = _create_attribute_enumerator,
 			.get_encoding = _get_encoding,
 			.destroy = _destroy,
@@ -688,4 +724,3 @@ ha_message_t *ha_message_parse(chunk_t data)

 	return &this->public;
 }
-
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2024 Tobias Brunner
 * Copyright (C) 2008 Martin Willi
 *
 * Copyright (C) secunet Security Networks AG
@@ -26,12 +27,13 @@
 #include <networking/host.h>
 #include <utils/identification.h>
 #include <sa/ike_sa_id.h>
+#include <crypto/proposal/proposal.h>
 #include <selectors/traffic_selector.h>

 /**
 * Protocol version of this implementation
 */
-#define HA_MESSAGE_VERSION 3
+#define HA_MESSAGE_VERSION 4

 typedef struct ha_message_t ha_message_t;
 typedef enum ha_message_type_t ha_message_type_t;
@@ -109,8 +111,10 @@ enum ha_message_attribute_t {
 	HA_NONCE_I,
 	/** chunk_t, responders nonce */
 	HA_NONCE_R,
-	/** chunk_t, diffie hellman shared secret */
+	/** chunk_t, KE shared secret */
 	HA_SECRET,
+	/** chunk_t, optional additional KE shared secret(s) */
+	HA_ADD_SECRET,
 	/** chunk_t, SKd of old SA if rekeying */
 	HA_OLD_SKD,
 	/** uint16_t, pseudo random function */
@@ -123,8 +127,10 @@ enum ha_message_attribute_t {
 	HA_ALG_ENCR_LEN,
 	/** uint16_t, integrity protection algorithm */
 	HA_ALG_INTEG,
-	/** uint16_t, DH group */
-	HA_ALG_DH,
+	/** uint16_t, KE method */
+	HA_ALG_KE,
+	/** chunk_t of uint16_t[], optional additional KE methods (IKEv2 only) */
+	HA_ALG_ADD_KES,
 	/** uint8_t, IPsec mode, TUNNEL|TRANSPORT|... */
 	HA_IPSEC_MODE,
 	/** uint8_t, IPComp protocol */
@@ -149,9 +155,9 @@ enum ha_message_attribute_t {
 	HA_ESN,
 	/** uint8_t, IKE version */
 	HA_IKE_VERSION,
-	/** chunk_t, own DH public value */
+	/** chunk_t, own DH public value (IKEv1 only) */
 	HA_LOCAL_DH,
-	/** chunk_t, remote DH public value */
+	/** chunk_t, remote DH public value (IKEv1 only) */
 	HA_REMOTE_DH,
 	/** chunk_t, shared secret for IKEv1 key derivation */
 	HA_PSK,
@@ -197,6 +203,13 @@ struct ha_message_t {
 	void (*add_attribute)(ha_message_t *this,
 						  ha_message_attribute_t attribute, ...);

+	/**
+	 * Add attributes for key exchange methods in the given proposal.
+	 *
+	 * @param proposal		proposal from which to get key exchange methods
+	 */
+	void (*add_key_exchange_methods)(ha_message_t *this, proposal_t *proposal);
+
 	/**
 	 * Create an enumerator over all attributes in a message.
 	 *
@@ -33,8 +33,7 @@
 #include <processing/jobs/initiate_tasks_job.h>

 /** Maximum number of key exchanges (including the initial one, if any) */
-#define MAX_KEY_EXCHANGES (ADDITIONAL_KEY_EXCHANGE_7 - \
-						   ADDITIONAL_KEY_EXCHANGE_1 + 2)
+#define MAX_KEY_EXCHANGES (MAX_ADDITIONAL_KEY_EXCHANGES + 1)

 typedef struct private_child_create_t private_child_create_t;

@@ -52,6 +52,12 @@ enum transform_type_t {
 	KEY_DERIVATION_FUNCTION = 262,
 };

+/**
+ * Maximum number of additional key exchanges.
+ */
+#define MAX_ADDITIONAL_KEY_EXCHANGES (ADDITIONAL_KEY_EXCHANGE_7 - \
+									  ADDITIONAL_KEY_EXCHANGE_1 + 1)
+
 /**
 * enum names for transform_type_t.
 */