diff --git a/pimd/pim_ssmpingd.c b/pimd/pim_ssmpingd.c
index 652999d..fd1eac0 100644
--- a/pimd/pim_ssmpingd.c
+++ b/pimd/pim_ssmpingd.c
@@ -215,7 +215,7 @@
 }
 
 static void ssmpingd_sendto(struct ssmpingd_sock *ss,
-			    const char *buf,
+			    const uint8_t *buf,
 			    int len,
 			    struct sockaddr_in to)
 {
@@ -250,7 +250,7 @@
   socklen_t fromlen = sizeof(from);
   socklen_t tolen = sizeof(to);
   int ifindex = -1;
-  char buf[1000];
+  uint8_t buf[1000];
   int len;
 
   ++ss->requests;