From 00954da5fe9123f4df398568267c07f1273eb712 Mon Sep 17 00:00:00 2001
From: Pavol Rusnak <stick@gk2.sk>
Date: Mon, 4 May 2015 19:53:06 +0200
Subject: [PATCH] fix /dev/urandom problem

---
 rand.c         | 22 ++++++++++++----------
 rand.h         |  1 -
 test-openssl.c |  1 -
 tests.c        |  1 -
 4 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/rand.c b/rand.c
index eb74ae45a..6bb72c35d 100644
--- a/rand.c
+++ b/rand.c
@@ -26,17 +26,13 @@
 
 #include "rand.h"
 
-static FILE *f;
-
-void init_rand(void)
-{
-	f = fopen("/dev/urandom", "r");
-}
+static FILE *frand = NULL;
 
 int finalize_rand(void)
 {
-	int err = fclose(f);
-	f = NULL;
+	if (!frand) return 0;
+	int err = fclose(frand);
+	frand = NULL;
 	return err;
 }
 
@@ -44,7 +40,10 @@ uint32_t random32(void)
 {
 	uint32_t r;
 	size_t len = sizeof(r);
-	size_t len_read = fread(&r, 1, len, f);
+	if (!frand) {
+		frand = fopen("/dev/urandom", "r");
+	}
+	size_t len_read = fread(&r, 1, len, frand);
 	(void)len_read;
 	assert(len_read == len);
 	return r;
@@ -59,7 +58,10 @@ uint32_t random_uniform(uint32_t n)
 
 void random_buffer(uint8_t *buf, size_t len)
 {
-	size_t len_read = fread(buf, 1, len, f);
+	if (!frand) {
+		frand = fopen("/dev/urandom", "r");
+	}
+	size_t len_read = fread(buf, 1, len, frand);
 	(void)len_read;
 	assert(len_read == len);
 }
diff --git a/rand.h b/rand.h
index 8d8160887..3c9655999 100644
--- a/rand.h
+++ b/rand.h
@@ -27,7 +27,6 @@
 #include <stdint.h>
 #include <stdlib.h>
 
-void init_rand(void);
 int finalize_rand(void);
 uint32_t random32(void);
 uint32_t random_uniform(uint32_t n);
diff --git a/test-openssl.c b/test-openssl.c
index ccef802ce..7103260fe 100644
--- a/test-openssl.c
+++ b/test-openssl.c
@@ -38,7 +38,6 @@ int main(int argc, char *argv[])
 	EC_GROUP *ecgroup;
 	int cnt = 0;
 
-	init_rand();
 	ecgroup = EC_GROUP_new_by_curve_name(NID_secp256k1);
 
 	unsigned long max_iterations = -1;
diff --git a/tests.c b/tests.c
index 94c9449e6..fc797ee1d 100644
--- a/tests.c
+++ b/tests.c
@@ -1442,7 +1442,6 @@ Suite *test_suite(void)
 int main(void)
 {
 	int number_failed;
-	init_rand(); // needed for scalar_multiply()
 	Suite *s = test_suite();
 	SRunner *sr = srunner_create(s);
 	srunner_run_all(sr, CK_VERBOSE);