Clean up and optimize Frodo implementation (#60)

Makefile

@@ -47,7 +47,7 @@ endif
 
 all: links lib tests
 
-objs/%.o: src/%.c
+objs/%.o: src/%.c | links
 	@mkdir -p $(@D)
 	$(CC) -c  $(CFLAGS) $(INCLUDES) $< -o $@
 
@@ -95,7 +95,7 @@ $(KEX_RLWE_MSRLN16_OBJS): $(KEX_RLWE_MSRLN16_HEADERS)
 
 # KEX_LWE_FRODO
 KEX_LWE_FRODO_OBJS := $(addprefix objs/kex_lwe_frodo/, lwe.o kex_lwe_frodo.o lwe_noise.o)
-KEX_LWE_FRODO_HEADERS := $(addprefix src/kex_lwe_frodo/, kex_lwe_frodo.h local.h)
+KEX_LWE_FRODO_HEADERS := $(addprefix src/kex_lwe_frodo/, kex_lwe_frodo.h local.h kex_lwe_frodo_macrify.c lwe_macrify.c)
 $(KEX_LWE_FRODO_OBJS): $(KEX_LWE_FRODO_HEADERS)
 
 # KEX_SIDH_CLN16

src/kex/kex.c

@@ -18,7 +18,7 @@ OQS_KEX *OQS_KEX_new(OQS_RAND *rand, enum OQS_KEX_alg_name alg_name, const uint8
 	case OQS_KEX_alg_rlwe_newhope:
 		return OQS_KEX_rlwe_newhope_new(rand);
 	case OQS_KEX_alg_lwe_frodo:
-		return OQS_KEX_lwe_frodo_new(rand, seed, seed_len, named_parameters);
+		return OQS_KEX_lwe_frodo_new_recommended(rand, seed, seed_len, named_parameters);
 	case OQS_KEX_alg_sidh_cln16:
 		return OQS_KEX_sidh_cln16_new(rand);
 	default:

src/kex_lwe_frodo/kex_lwe_frodo.c

@@ -13,6 +13,7 @@
 
 #include <oqs/kex.h>
 #include <oqs/rand.h>
+#include <oqs/common.h>
 
 #include "kex_lwe_frodo.h"
 #include "local.h"
@@ -21,115 +22,16 @@
 
 #include <stdio.h>
 
-OQS_KEX *OQS_KEX_lwe_frodo_new(OQS_RAND *rand, const uint8_t *seed, const size_t seed_len, const char *named_parameters) {
-
-	OQS_KEX *k;
-	struct oqs_kex_lwe_frodo_params *params;
-
-	if ((seed_len == 0) || (seed == NULL)) {
-		return NULL;
-	}
-
-	k = malloc(sizeof(OQS_KEX));
-	if (k == NULL) {
-		goto err;
-	}
-	k->named_parameters = NULL;
-	k->method_name = NULL;
-
-	k->params = malloc(sizeof(struct oqs_kex_lwe_frodo_params));
-	if (NULL == k->params) {
-		goto err;
-	}
-	params = (struct oqs_kex_lwe_frodo_params *) k->params;
-	params->cdf_table = NULL;
-	params->seed = NULL;
-	params->param_name = NULL;
-
-	k->rand = rand;
-	k->ctx = NULL;
-	k->alice_priv_free = &OQS_KEX_lwe_frodo_alice_priv_free;
-	k->free = &OQS_KEX_lwe_frodo_free;
-
-	if (strcmp(named_parameters, "recommended") == 0) {
-
-		k->alice_0 = &OQS_KEX_lwe_frodo_alice_0_recommended;
-		k->bob = &OQS_KEX_lwe_frodo_bob_recommended;
-		k->alice_1 = &OQS_KEX_lwe_frodo_alice_1_recommended;
-
-		k->method_name = strdup("LWE Frodo recommended");
-		if (NULL == k->method_name) {
-			goto err;
-		}
-		k->estimated_classical_security = 144;
-		k->estimated_quantum_security = 130;
-		k->named_parameters = strdup(named_parameters);
-		if (k->named_parameters == NULL) {
-			goto err;
-		}
-
-		params->seed = malloc(seed_len);
-		if (NULL == params->seed) {
-			goto err;
-		}
-		memcpy(params->seed, seed, seed_len);
-		params->seed_len = seed_len;
-		params->param_name = strdup("recommended");
-		if (NULL == params->param_name) {
-			goto err;
-		}
-		params->log2_q = 15;
-		params->q = 1 << params->log2_q;
-		params->n = 752;
-		params->extracted_bits = 4;
-		params->nbar = 8;
-		params->key_bits = 256;
-		params->rec_hint_len = LWE_DIV_ROUNDUP(params->nbar * params->nbar, 8);
-		params->pub_len = LWE_DIV_ROUNDUP(params->n * params->nbar * params->log2_q, 8);
-		params->stripe_step = 8;
-		params->sampler_num = 12;
-		params->cdf_table_len = 6;
-		params->cdf_table = malloc(params->cdf_table_len * sizeof(uint16_t));
-		if (NULL == params->cdf_table) {
-			goto err;
-		}
-		uint16_t cdf_table_tmp[6] = {602, 1521, 1927, 2031, 2046, 2047};
-		memcpy(params->cdf_table, cdf_table_tmp, sizeof(cdf_table_tmp));
-
-	} else {
-
-		goto err;
-
-	}
-
-	return k;
-
-err:
-	if (k) {
-		if (k->params) {
-			free(params->cdf_table);
-			free(params->seed);
-			free(params->param_name);
-			free(k->params);
-		}
-		free(k->named_parameters);
-		free(k->method_name);
-		free(k);
-	}
-	return NULL;
-
-}
-
 // pre-process code to obtain "recommended" functions
+#include "recommended.h"
 #define MACRIFY(NAME) NAME ## _recommended
 #include "kex_lwe_frodo_macrify.c"
 // 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) {
-	if (alice_priv) {
-		free(alice_priv);
-	}
+	free(alice_priv);
 }
 
 void OQS_KEX_lwe_frodo_free(OQS_KEX *k) {

src/kex_lwe_frodo/kex_lwe_frodo.h

@@ -12,7 +12,7 @@
 #include <oqs/kex.h>
 #include <oqs/rand.h>
 
-OQS_KEX *OQS_KEX_lwe_frodo_new(OQS_RAND *rand, const uint8_t *seed, const size_t seed_len, const char *named_parameters);
+OQS_KEX *OQS_KEX_lwe_frodo_new_recommended(OQS_RAND *rand, const uint8_t *seed, const size_t seed_len, const char *named_parameters);
 
 int OQS_KEX_lwe_frodo_alice_0_recommended(OQS_KEX *k, void **alice_priv, uint8_t **alice_msg, size_t *alice_msg_len);
 int OQS_KEX_lwe_frodo_bob_recommended(OQS_KEX *k, const uint8_t *alice_msg, const size_t alice_msg_len, uint8_t **bob_msg, size_t *bob_msg_len, uint8_t **key, size_t *key_len);