5 files changed, 35 insertions, 10 deletions

diff --git a/src/cm/cm.c b/src/cm/cm.c
index 587f497..8fa174d 100644
--- a/src/cm/cm.c
+++ b/src/cm/cm.c
@@ -11,13 +11,18 @@
 int cm_do() {
 	debug_log_start("Starting Complex Multiplication method");
 
+	int result = 0;
 	curve_t *curve = custom_curve();
-	output_o_begin();
-	output_o(curve);
-	output_o_end();
+	if (curve) {
+		output_o_begin();
+		output_o(curve);
+		output_o_end();
 
-	curve_free(&curve);
+		curve_free(&curve);
+	} else {
+		result = 1;
+	}
 
 	debug_log_start("Finished Complex Multiplication method");
-	return 0;
+	return result;
 }
diff --git a/src/cm/custom.c b/src/cm/custom.c
index 33ebde3..71d6625 100644
--- a/src/cm/custom.c
+++ b/src/cm/custom.c
@@ -3,7 +3,6 @@
  * Copyright (C) 2017 J08nY
  */
 #include "custom.h"
-#include "io/input.h"
 #include "io/output.h"
 #include "obj/curve.h"
 #include "obj/point.h"
@@ -16,7 +15,6 @@ static size_t custom_add_primes(GEN r, GEN order, GEN **primes,
 	if (nprimes == 0) {
 		nalloc = 10;
 		*primes = try_calloc(sizeof(GEN) * nalloc);
-		debug_log("calloc %lu", sizeof(GEN) * nalloc);
 	}
 
 	GEN logN = ground(glog(order, BIGDEFAULTPREC));
@@ -48,7 +46,7 @@ static size_t custom_add_primes(GEN r, GEN order, GEN **primes,
 	return nprimes;
 }
 
-static custom_quadr_t custom_prime_random(GEN order) {
+static custom_quadr_t custom_quadr(GEN order) {
 	pari_sp ltop = avma;
 	custom_quadr_t result = {0};
 
@@ -115,8 +113,12 @@ static custom_quadr_t custom_prime_random(GEN order) {
 
 curve_t *custom_curve() {
 	GEN order = strtoi(cfg->cm_order);
+	if (!isprime(order)) {
+		fprintf(err, "Currently, order must be prime for CM to work.\n");
+		return NULL;
+	}
 
-	custom_quadr_t quadr = custom_prime_random(order);
+	custom_quadr_t quadr = custom_quadr(order);
 	debug_log("order = %Pi", order);
 	debug_log("p = %Pi, t = %Pi, v = %Pi, D = %Pi, ", quadr.p, quadr.t, quadr.v,
 	          quadr.D);
diff --git a/src/io/cli.c b/src/io/cli.c
index bc5764f..37c1a8e 100644
--- a/src/io/cli.c
+++ b/src/io/cli.c
@@ -149,6 +149,10 @@ static void cli_end(struct argp_state *state) {
 		argp_failure(state, 1, 0,
 		             "Brainpool algorithm only creates prime field curves.");
 	}
+	if (cfg->method == METHOD_CM && cfg->field == FIELD_BINARY) {
+		argp_failure(state, 1, 0,
+		             "Complex multiplication only creates prime field curves.");
+	}
 	// default values
 	if (!cfg->count) {
 		cfg->count = 1;
diff --git a/test/ecgen.sh b/test/ecgen.sh
index 2383e34..46ee998 100755
--- a/test/ecgen.sh
+++ b/test/ecgen.sh
@@ -136,6 +136,12 @@ function hex() {
 	assert_raises "${ecgen} --fp -r --hex-check=\"abc\" 32 | grep \"abc\""
 }
 
+function cm() {
+    start_test
+    assert_raises "${ecgen} --fp --order=2147483723 32" 1
+    assert_raises "${ecgen} --fp --order=2147483783 32"
+}
+
 . ${ASSERT} -v
 start_suite
 runs
@@ -148,4 +154,5 @@ invalid
 twist
 cli
 hex
+cm
 end_suite ecgen
diff --git a/test/src/cm/test_custom.c b/test/src/cm/test_custom.c
index c94657d..df1ada8 100644
--- a/test/src/cm/test_custom.c
+++ b/test/src/cm/test_custom.c
@@ -30,11 +30,18 @@ Test(custom, test_curve_one) {
 	cfg->bits = 128;
 	cfg->cm_order = "263473633827487324648193013259296339349";
 	GEN order = strtoi(cfg->cm_order);
-	cfg->random = RANDOM_ALL;
 
 	curve_t *curve = custom_curve();
 	cr_assert_not_null(curve, );
 	cr_assert(equalii(curve->order, order), );
 	cr_assert(equalii(ellcard(curve->curve, NULL), order), );
 	curve_free(&curve);
+}
+
+Test(custom, test_curve_other) {
+	cfg->bits = 32;
+	cfg->cm_order = "2147483723";
+
+	curve_t *curve = custom_curve();
+	cr_assert_null(curve, );
 }
\ No newline at end of file