Fix alice_priv_free in implementations (#293)

* fix

replaced free by OQS_MEM_secure_free where necessary

* commit

* commit

* removed //free(alice_priv)

.gitignore

@@ -105,3 +105,7 @@ data/
 # Exceptions
 !/src/kex_sidh_msr/config.h
 !src/sig_picnic/external/config.h.in
+
+# Misc (master branch)
+.objs_upstream
+*_kem*

src/kex/minimal_kex_oqs.c

@@ -66,7 +66,7 @@ int main(void) {
 	printf("===============================================================\n");
 
 	/* Alice's initial message */
-	int success = OQS_KEX_alice_0(kex, &alice_priv, &alice_msg, &alice_msg_len);
+	OQS_STATUS success = OQS_KEX_alice_0(kex, &alice_priv, &alice_msg, &alice_msg_len);
 	if (success != OQS_SUCCESS) {
 		eprintf("ERROR: OQS_KEX_alice_0 failed!\n");
 		cleanup(alice_msg, alice_msg_len, alice_key, alice_key_len, bob_msg,

src/kex_code_mcbits/kex_code_mcbits.c

@@ -145,7 +145,7 @@ cleanup:
 
 void OQS_KEX_code_mcbits_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
 	if (alice_priv) {
-		free(alice_priv);
+		OQS_MEM_secure_free(alice_priv, CRYPTO_SECRETKEYBYTES);
 	}
 }
 

src/kex_lwe_frodo/kex_lwe_frodo.c

@@ -20,12 +20,13 @@
 #include "recommended.h"
 #define MACRIFY(NAME) NAME##_recommended
 #include "kex_lwe_frodo_macrify.c"
+static size_t alice_priv_key_len = PARAMS_N * PARAMS_NBAR * sizeof(uint16_t);
 // undefine macros to avoid any confusion later
 #include "recommended.h"
 #undef MACRIFY
 
 void OQS_KEX_lwe_frodo_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
-	free(alice_priv);
+	OQS_MEM_secure_free(alice_priv, alice_priv_key_len);
 }
 
 void OQS_KEX_lwe_frodo_free(OQS_KEX *k) {

src/kex_ntru/kex_ntru.c

@@ -222,7 +222,7 @@ cleanup:
 void OQS_KEX_ntru_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
 	if (alice_priv) {
 		OQS_KEX_ntru_alice_priv *ntru_alice_priv = (OQS_KEX_ntru_alice_priv *) alice_priv;
-		free(ntru_alice_priv->priv_key);
+		OQS_MEM_secure_free(ntru_alice_priv->priv_key, ntru_alice_priv->priv_key_len);
 	}
 	free(alice_priv);
 }

src/kex_rlwe_bcns15/kex_rlwe_bcns15.c

@@ -175,7 +175,7 @@ cleanup:
 
 void OQS_KEX_rlwe_bcns15_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
 	if (alice_priv) {
-		free(alice_priv);
+		OQS_MEM_secure_free(alice_priv, 1024 * sizeof(uint32_t));
 	}
 }
 

src/kex_rlwe_msrln16/kex_rlwe_msrln16.c

@@ -155,7 +155,7 @@ cleanup:
 
 void OQS_KEX_rlwe_msrln16_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
 	if (alice_priv) {
-		free(alice_priv);
+		OQS_MEM_secure_free(alice_priv, 1024 * sizeof(uint32_t));
 	}
 }
 

src/kex_rlwe_newhope/kex_rlwe_newhope.c

@@ -150,7 +150,7 @@ cleanup:
 
 void OQS_KEX_rlwe_newhope_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
 	if (alice_priv) {
-		free(alice_priv);
+		OQS_MEM_secure_free(alice_priv, sizeof(poly));
 	}
 }
 

src/kex_sidh_iqc_ref/kex_sidh_iqc_ref.c

@@ -206,7 +206,9 @@ OQS_STATUS OQS_KEX_sidh_iqc_ref_alice_1(OQS_KEX *k, const void *alice_priv,
 
 void OQS_KEX_sidh_iqc_ref_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
 	if (alice_priv) {
-		free(alice_priv);
+		uint32_t prime_size = (mpz_sizeinbase(characteristic, 2) + 7) / 8;
+		uint32_t private_key_size = 2 * prime_size;
+		OQS_MEM_secure_free(alice_priv, private_key_size);
 	}
 }
 

src/kex_sidh_msr/kex_sidh_msr.c

@@ -302,9 +302,10 @@ cleanup:
 	return ret;
 }
 
-void OQS_KEX_sidh_msr_alice_priv_free(UNUSED OQS_KEX *k, void *alice_priv) {
+void OQS_KEX_sidh_msr_alice_priv_free(OQS_KEX *k, void *alice_priv) {
 	if (alice_priv) {
-		free(alice_priv);
+		SIDH_CTX *sidh_ctx = (SIDH_CTX *) k->ctx;
+		OQS_MEM_secure_free(alice_priv, (sidh_ctx->priv_key_len) * sizeof(uint8_t));
 	}
 }
 

src/sig/minimal_sig_oqs.c

@@ -71,7 +71,7 @@ int main(void) {
 	}
 
 	/* Generates the signature key pair */
-	int success = OQS_SIG_keygen(s, priv, pub);
+	OQS_STATUS success = OQS_SIG_keygen(s, priv, pub);
 	if (success != OQS_SUCCESS) {
 		eprintf("ERROR: OQS_SIG_keygen failed!\n");
 		cleanup(msg, msg_len, sig, sig_len, pub, priv, s, rnd);