ustream-mbedtls: Use getrandom() instead of /dev/urandom

[project/ustream-ssl.git] / ustream-mbedtls.c

diff --git a/ustream-mbedtls.c b/ustream-mbedtls.c
index e79e37ba5051e05642e83911526cce5831766a25..7fc78742f7c409389a5af5e1cc39d73ff87c78e3 100644 (file)
--- a/ustream-mbedtls.c
+++ b/ustream-mbedtls.c
@@ -17,6 +17,7 @@
  */
 
 #include <sys/types.h>
+#include <sys/random.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <stdlib.h>
@@ -25,8 +26,6 @@
 #include "ustream-ssl.h"
 #include "ustream-internal.h"
 
-static int urandom_fd = -1;
-
 static int s_ustream_read(void *ctx, unsigned char *buf, size_t len)
 {
        struct ustream *s = ctx;
@@ -66,21 +65,12 @@ __hidden void ustream_set_io(struct ustream_ssl_ctx *ctx, void *ssl, struct ustr
        mbedtls_ssl_set_bio(ssl, conn, s_ustream_write, s_ustream_read, NULL);
 }
 
-static bool urandom_init(void)
+static int _random(void *ctx, unsigned char *out, size_t len)
 {
-       if (urandom_fd > -1)
-               return true;
+       ssize_t ret;
 
-       urandom_fd = open("/dev/urandom", O_RDONLY);
-       if (urandom_fd < 0)
-               return false;
-
-       return true;
-}
-
-static int _urandom(void *ctx, unsigned char *out, size_t len)
-{
-       if (read(urandom_fd, out, len) < 0)
+       ret = getrandom(out, len, 0);
+       if (ret < 0 || (size_t)ret != len)
                return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
 
        return 0;
@@ -134,9 +124,6 @@ __ustream_ssl_context_new(bool server)
        mbedtls_ssl_config *conf;
        int ep;
 
-       if (!urandom_init())
-               return NULL;
-
        ctx = calloc(1, sizeof(*ctx));
        if (!ctx)
                return NULL;
@@ -159,7 +146,7 @@ __ustream_ssl_context_new(bool server)
 
        mbedtls_ssl_config_defaults(conf, ep, MBEDTLS_SSL_TRANSPORT_STREAM,
                                    MBEDTLS_SSL_PRESET_DEFAULT);
-       mbedtls_ssl_conf_rng(conf, _urandom, NULL);
+       mbedtls_ssl_conf_rng(conf, _random, NULL);
 
        if (server) {
                mbedtls_ssl_conf_authmode(conf, MBEDTLS_SSL_VERIFY_NONE);