1 files changed, 89 insertions, 0 deletions
diff --git a/openbsd-compat/arc4random.h b/openbsd-compat/arc4random.h
new file mode 100644
index 0000000..5af3a44
--- /dev/null
+++ b/openbsd-compat/arc4random.h
@@ -0,0 +1,89 @@
+/*	$OpenBSD: arc4random_linux.h,v 1.12 2019/07/11 10:37:28 inoguchi Exp $	*/
+
+/*
+ * Copyright (c) 1996, David Mazieres <dm@uun.org>
+ * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
+ * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
+ * Copyright (c) 2014, Theo de Raadt <deraadt@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.
+ */
+
+/*
+ * Stub functions for portability.  From LibreSSL with some adaptations.
+ */
+
+#include <sys/mman.h>
+
+#include <signal.h>
+
+/* OpenSSH isn't multithreaded */
+#define _ARC4_LOCK()
+#define _ARC4_UNLOCK()
+#define _ARC4_ATFORK(f)
+
+static inline void
+_getentropy_fail(void)
+{
+	fatal("getentropy failed");
+}
+
+static volatile sig_atomic_t _rs_forked;
+
+static inline void
+_rs_forkhandler(void)
+{
+	_rs_forked = 1;
+}
+
+static inline void
+_rs_forkdetect(void)
+{
+	static pid_t _rs_pid = 0;
+	pid_t pid = getpid();
+
+	if (_rs_pid == 0 || _rs_pid == 1 || _rs_pid != pid || _rs_forked) {
+		_rs_pid = pid;
+		_rs_forked = 0;
+		if (rs)
+			memset(rs, 0, sizeof(*rs));
+	}
+}
+
+static inline int
+_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
+{
+#if defined(MAP_ANON) && defined(MAP_PRIVATE)
+	if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE,
+	    MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
+		return (-1);
+
+	if ((*rsxp = mmap(NULL, sizeof(**rsxp), PROT_READ|PROT_WRITE,
+	    MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) {
+		munmap(*rsp, sizeof(**rsp));
+		*rsp = NULL;
+		return (-1);
+	}
+#else
+	if ((*rsp = calloc(1, sizeof(**rsp))) == NULL)
+		return (-1);
+	if ((*rsxp = calloc(1, sizeof(**rsxp))) == NULL) {
+		free(*rsp);
+		*rsp = NULL;
+		return (-1);
+	}
+#endif
+
+	_ARC4_ATFORK(_rs_forkhandler);
+	return (0);
+}