1 files changed, 52 insertions, 0 deletions
diff --git a/src/crypto/crypto_ops_builder/randombytes.c b/src/crypto/crypto_ops_builder/randombytes.c
new file mode 100755
index 000000000..fa7d42149
--- /dev/null
+++ b/src/crypto/crypto_ops_builder/randombytes.c
@@ -0,0 +1,52 @@
+#ifndef _WIN32
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+/* it's really stupid that there isn't a syscall for this */
+
+static int ed25519_random_fd = -1;
+
+static inline void ed25519_randombytes(unsigned char *x,unsigned long long xlen)
+{
+  int i;
+
+  if (ed25519_random_fd == -1) {
+    for (;;) {
+      ed25519_random_fd = open("/dev/urandom",O_RDONLY);
+      if (ed25519_random_fd != -1) break;
+      sleep(1);
+    }
+  }
+
+  while (xlen > 0) {
+    if (xlen < 1048576) i = xlen; else i = 1048576;
+
+    i = read(ed25519_random_fd,x,i);
+    if (i < 1) {
+      sleep(1);
+      continue;
+    }
+
+    x += i;
+    xlen -= i;
+  }
+}
+
+#else
+#include <windows.h>
+#include <wincrypt.h>
+
+static inline void ed25519_randombytes(unsigned char *x,unsigned long long xlen)
+{
+  HCRYPTPROV prov = 0;
+
+  CryptAcquireContextW(&prov, NULL, NULL,
+    PROV_RSA_FULL, CRYPT_VERIFYCONTEXT | CRYPT_SILENT);
+
+  CryptGenRandom(prov, xlen, x);
+  CryptReleaseContext(prov, 0);
+}
+
+#endif /* _WIN32  */