From 99b82bf53792d48b5d0c3f9edcccc6e53c9510fe Mon Sep 17 00:00:00 2001

Message-Id: <99b82bf53792d48b5d0c3f9edcccc6e53c9510fe.1488376601.git.dcaratti@redhat.com>

From: Sabrina Dubroca <sd@queasysnail.net>

Date: Fri, 21 Oct 2016 14:45:29 +0200

Subject: [PATCH] mka: Implement reference counting on data_key

struct data_key already had a 'user' field for reference counting, but

it was basically unused.

Add an ieee802_1x_kay_use_data_key() function to take a reference on a

key, and use ieee802_1x_kay_deinit_data_key() to release the reference.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>

---

 src/pae/ieee802_1x_kay.c | 28 ++++++++++++++++++++++++----

 src/pae/ieee802_1x_kay.h |  2 +-

 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/src/pae/ieee802_1x_kay.c b/src/pae/ieee802_1x_kay.c

index e312d04..63bbd13 100644

--- a/src/pae/ieee802_1x_kay.c

+++ b/src/pae/ieee802_1x_kay.c

@@ -411,6 +411,8 @@ ieee802_1x_kay_get_peer_sci(struct ieee802_1x_mka_participant *participant,

 }

+static void ieee802_1x_kay_use_data_key(struct data_key *pkey);

+

 /**

  * ieee802_1x_kay_init_receive_sa -

  */

@@ -429,6 +431,7 @@ ieee802_1x_kay_init_receive_sa(struct receive_sc *psc, u8 an, u32 lowest_pn,

 		return NULL;

 	}

+	ieee802_1x_kay_use_data_key(key);

 	psa->pkey = key;

 	psa->lowest_pn = lowest_pn;

 	psa->next_pn = lowest_pn;

@@ -447,11 +450,14 @@ ieee802_1x_kay_init_receive_sa(struct receive_sc *psc, u8 an, u32 lowest_pn,

 }

+static void ieee802_1x_kay_deinit_data_key(struct data_key *pkey);

+

 /**

  * ieee802_1x_kay_deinit_receive_sa -

  */

 static void ieee802_1x_kay_deinit_receive_sa(struct receive_sa *psa)

 {

+	ieee802_1x_kay_deinit_data_key(psa->pkey);

 	psa->pkey = NULL;

 	wpa_printf(MSG_DEBUG,

 		   "KaY: Delete receive SA(an: %hhu) of SC",

@@ -1612,6 +1618,7 @@ ieee802_1x_mka_decode_dist_sak_body(

 	sa_key->an = body->dan;

 	ieee802_1x_kay_init_data_key(sa_key);

+	ieee802_1x_kay_use_data_key(sa_key);

 	dl_list_add(&participant->sak_list, &sa_key->list);

 	ieee802_1x_cp_set_ciphersuite(kay->cp, cs->id);

@@ -1873,7 +1880,17 @@ static struct mka_param_body_handler mka_body_handler[] = {

 /**

- * ieee802_1x_kay_deinit_data_key -

+ * ieee802_1x_kay_use_data_key - Take reference on a key

+ */

+static void ieee802_1x_kay_use_data_key(struct data_key *pkey)

+{

+	pkey->user++;

+}

+

+

+/**

+ * ieee802_1x_kay_deinit_data_key - Release reference on a key and

+ * free if there are no remaining users

  */

 static void ieee802_1x_kay_deinit_data_key(struct data_key *pkey)

 {

@@ -1884,7 +1901,6 @@ static void ieee802_1x_kay_deinit_data_key(struct data_key *pkey)

 	if (pkey->user > 1)

 		return;

-	dl_list_del(&pkey->list);

 	os_free(pkey->key);

 	os_free(pkey);

 }

@@ -1994,7 +2010,9 @@ ieee802_1x_kay_generate_new_sak(struct ieee802_1x_mka_participant *participant)

 	participant->new_key = sa_key;

+	ieee802_1x_kay_use_data_key(sa_key);

 	dl_list_add(&participant->sak_list, &sa_key->list);

+

 	ieee802_1x_cp_set_ciphersuite(kay->cp, cs->id);

 	ieee802_1x_cp_sm_step(kay->cp);

 	ieee802_1x_cp_set_offset(kay->cp, kay->macsec_confidentiality);

@@ -2436,6 +2454,7 @@ ieee802_1x_kay_init_transmit_sa(struct transmit_sc *psc, u8 an, u32 next_PN,

 		psa->confidentiality = FALSE;

 	psa->an = an;

+	ieee802_1x_kay_use_data_key(key);

 	psa->pkey = key;

 	psa->next_pn = next_PN;

 	psa->sc = psc;

@@ -2457,6 +2476,7 @@ ieee802_1x_kay_init_transmit_sa(struct transmit_sc *psc, u8 an, u32 next_PN,

  */

 static void ieee802_1x_kay_deinit_transmit_sa(struct transmit_sa *psa)

 {

+	ieee802_1x_kay_deinit_data_key(psa->pkey);

 	psa->pkey = NULL;

 	wpa_printf(MSG_DEBUG,

 		   "KaY: Delete transmit SA(an: %hhu) of SC",

@@ -2708,6 +2728,7 @@ int ieee802_1x_kay_delete_sas(struct ieee802_1x_kay *kay,

 	dl_list_for_each_safe(sa_key, pre_key, &principal->sak_list,

 			      struct data_key, list) {

 		if (is_ki_equal(&sa_key->key_identifier, ki)) {

+			dl_list_del(&sa_key->list);

 			ieee802_1x_kay_deinit_data_key(sa_key);

 			break;

 		}

@@ -3375,8 +3396,7 @@ ieee802_1x_kay_delete_mka(struct ieee802_1x_kay *kay, struct mka_key_name *ckn)

 		sak = dl_list_entry(participant->sak_list.next,

 				    struct data_key, list);

 		dl_list_del(&sak->list);

-		os_free(sak->key);

-		os_free(sak);

+		ieee802_1x_kay_deinit_data_key(sak);

 	}

 	while (!dl_list_empty(&participant->rxsc_list)) {

 		rxsc = dl_list_entry(participant->rxsc_list.next,

diff --git a/src/pae/ieee802_1x_kay.h b/src/pae/ieee802_1x_kay.h

index 5233cb2..576a8a0 100644

--- a/src/pae/ieee802_1x_kay.h

+++ b/src/pae/ieee802_1x_kay.h

@@ -70,7 +70,7 @@ struct data_key {

 	Boolean rx_latest;

 	Boolean tx_latest;

-	int user;  /* FIXME: to indicate if it can be delete safely */

+	int user;

 	struct dl_list list;

 };

-- 

2.7.4