update go api

go/gmssl/rand.go

@@ -0,0 +1,26 @@
+/* +build cgo */
+package gmssl
+
+/*
+#include <openssl/rand.h>
+*/
+import "C"
+
+import (
+	"errors"
+	"unsafe"
+)
+
+func SeedRandom(seed []byte) error {
+	C.RAND_seed(unsafe.Pointer(&seed[0]), C.int(len(seed)))
+	return nil
+}
+
+func GenerateRandom(length int) ([]byte, error) {
+	outbuf := make([]byte, length)
+	if 1 != C.RAND_bytes((*C.uchar)(&outbuf[0]), C.int(length)) {
+		return nil, errors.New("GmSSL Failure")
+	}
+
+	return outbuf[:length], nil
+}