1 files changed, 83 insertions, 0 deletions
diff --git a/openbsd-compat/bsd-getentropy.c b/openbsd-compat/bsd-getentropy.c
new file mode 100644
index 0000000..554dfad
--- /dev/null
+++ b/openbsd-compat/bsd-getentropy.c
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 1996, David Mazieres <dm@uun.org>
+ * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
+ * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "includes.h"
+
+#ifndef SSH_RANDOM_DEV
+# define SSH_RANDOM_DEV "/dev/urandom"
+#endif /* SSH_RANDOM_DEV */
+
+#include <sys/types.h>
+#ifdef HAVE_SYS_RANDOM_H
+# include <sys/random.h>
+#endif
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#ifdef WITH_OPENSSL
+#include <openssl/rand.h>
+#include <openssl/err.h>
+#endif
+
+#include "log.h"
+
+int
+_ssh_compat_getentropy(void *s, size_t len)
+{
+#ifdef WITH_OPENSSL
+	if (RAND_bytes(s, len) <= 0)
+		fatal("Couldn't obtain random bytes (error 0x%lx)",
+		    (unsigned long)ERR_get_error());
+#else
+	int fd, save_errno;
+	ssize_t r;
+	size_t o = 0;
+
+#ifdef HAVE_GETENTROPY
+	if (r = getentropy(s, len) == 0)
+		return 0;
+#endif /* HAVE_GETENTROPY */
+#ifdef HAVE_GETRANDOM
+	if ((r = getrandom(s, len, 0)) > 0 && (size_t)r == len)
+		return 0;
+#endif /* HAVE_GETRANDOM */
+
+	if ((fd = open(SSH_RANDOM_DEV, O_RDONLY)) == -1) {
+		save_errno = errno;
+		/* Try egd/prngd before giving up. */
+		if (seed_from_prngd(s, len) == 0)
+			return 0;
+		fatal("Couldn't open %s: %s", SSH_RANDOM_DEV,
+		    strerror(save_errno));
+	}
+	while (o < len) {
+		r = read(fd, (u_char *)s + o, len - o);
+		if (r < 0) {
+			if (errno == EAGAIN || errno == EINTR ||
+			    errno == EWOULDBLOCK)
+				continue;
+			fatal("read %s: %s", SSH_RANDOM_DEV, strerror(errno));
+		}
+		o += r;
+	}
+	close(fd);
+#endif /* WITH_OPENSSL */
+	return 0;
+}