prf_plus_create() can return NULL on failure

src/libcharon/sa/ikev1/keymat_v1.c

@@ -614,6 +614,11 @@ METHOD(keymat_v1_t, derive_child_keys, bool,
 	DBG4(DBG_CHD, "initiator SA seed %B", &seed);
 
 	prf_plus = prf_plus_create(this->prf, FALSE, seed);
+	if (!prf_plus)
+	{
+		chunk_clear(&secret);
+		return FALSE;
+	}
 	if (!prf_plus->allocate_bytes(prf_plus, enc_size, encr_i) ||
 		!prf_plus->allocate_bytes(prf_plus, int_size, integ_i))
 	{
@@ -627,6 +632,11 @@ METHOD(keymat_v1_t, derive_child_keys, bool,
 					  chunk_from_thing(spi_i), nonce_i, nonce_r);
 	DBG4(DBG_CHD, "responder SA seed %B", &seed);
 	prf_plus = prf_plus_create(this->prf, FALSE, seed);
+	if (!prf_plus)
+	{
+		chunk_clear(&secret);
+		return FALSE;
+	}
 	if (!prf_plus->allocate_bytes(prf_plus, enc_size, encr_r) ||
 		!prf_plus->allocate_bytes(prf_plus, int_size, integ_r))
 	{

src/libcharon/sa/ikev2/keymat_v2.c

@@ -355,6 +355,12 @@ METHOD(keymat_v2_t, derive_ike_keys, bool,
 	chunk_free(&fixed_nonce);
 	chunk_clear(&prf_plus_seed);
 
+	if (!prf_plus)
+	{
+		DESTROY_IF(rekey_prf);
+		return FALSE;
+	}
+
 	/* KEYMAT = SK_d | SK_ai | SK_ar | SK_ei | SK_er | SK_pi | SK_pr */
 
 	/* SK_d is used for generating CHILD_SA key mat => store for later use */
@@ -528,6 +534,10 @@ METHOD(keymat_v2_t, derive_child_keys, bool,
 
 	this->prf->set_key(this->prf, this->skd);
 	prf_plus = prf_plus_create(this->prf, TRUE, seed);
+	if (!prf_plus)
+	{
+		return FALSE;
+	}
 
 	if (!prf_plus->allocate_bytes(prf_plus, enc_size, encr_i) ||
 		!prf_plus->allocate_bytes(prf_plus, int_size, integ_i) ||

src/libstrongswan/crypto/prf_plus.h

@@ -63,7 +63,7 @@ struct prf_plus_t {
  * @param prf				prf object to use, must be destroyd after prf+.
  * @param counter			use an appending counter byte (for IKEv2 variant)
  * @param seed				input seed for prf
- * @return					prf_plus_t object
+ * @return					prf_plus_t object, NULL on failure
  */
 prf_plus_t *prf_plus_create(prf_t *prf, bool counter, chunk_t seed);