X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fcrypto.c;h=3244a0b4628bdd2e6ddb6f49dbf1a0c30fab17ad;hb=9cde0d32cf209388cc59b06b7dcb0c3432f97da5;hp=2e2fa5386555c02b1e8c5632ee597c6c52bd513d;hpb=7db92fb1932065e40cd4709989e429fca2d49778;p=meshlink

diff --git a/src/crypto.c b/src/crypto.c
index 2e2fa538..3244a0b4 100644
--- a/src/crypto.c
+++ b/src/crypto.c
@@ -28,9 +28,14 @@
 static int random_fd = -1;
 
 void crypto_init(void) {
+	assert(random_fd == -1);
+
 	random_fd = open("/dev/urandom", O_RDONLY);
-	if(random_fd < 0)
+
+	if(random_fd < 0) {
 		random_fd = open("/dev/random", O_RDONLY);
+	}
+
 	if(random_fd < 0) {
 		fprintf(stderr, "Could not open source of random numbers: %s\n", strerror(errno));
 		abort();
@@ -38,7 +43,32 @@ void crypto_init(void) {
 }
 
 void crypto_exit(void) {
+	assert(random_fd != -1);
+
 	close(random_fd);
+	random_fd = -1;
+}
+
+void randomize(void *out, size_t outlen) {
+	assert(outlen);
+
+	char *ptr = out;
+
+	while(outlen) {
+		size_t len = read(random_fd, ptr, outlen);
+
+		if(len <= 0) {
+			if(errno == EAGAIN || errno == EINTR) {
+				continue;
+			}
+
+			fprintf(stderr, "Could not read random numbers: %s\n", strerror(errno));
+			abort();
+		}
+
+		ptr += len;
+		outlen -= len;
+	}
 }
 
 #else
@@ -58,6 +88,8 @@ void crypto_exit(void) {
 }
 
 void randomize(void *out, size_t outlen) {
+	assert(outlen);
+
 	if(!CryptGenRandom(prov, outlen, out)) {
 		fprintf(stderr, "CryptGenRandom() failed\n");
 		abort();