3 files changed, 83 insertions, 0 deletions

diff --git a/utils/mount/network.c b/utils/mount/network.c
index c092571..a5b0b71 100644
--- a/utils/mount/network.c
+++ b/utils/mount/network.c
@@ -53,6 +53,10 @@
 #define NFS_PORT 2049
 #endif
 
+#if SIZEOF_SOCKLEN_T - 0 == 0
+#define socklen_t unsigned int
+#endif
+
 extern int nfs_mount_data_version;
 extern char *progname;
 extern int verbose;
@@ -510,3 +514,78 @@ void mnt_closeclnt(CLIENT *clnt, int msock)
 	clnt_destroy(clnt);
 	close(msock);
 }
+
+/*
+ * Sigh... getport() doesn't actually check the version number.
+ * In order to make sure that the server actually supports the service
+ * we're requesting, we open and RPC client, and fire off a NULL
+ * RPC call.
+ */
+int clnt_ping(struct sockaddr_in *saddr, const unsigned long prog,
+		const unsigned long vers, const unsigned int prot,
+		struct sockaddr_in *caddr)
+{
+	CLIENT *clnt = NULL;
+	int sock, stat;
+	static char clnt_res;
+	struct sockaddr dissolve;
+
+	rpc_createerr.cf_stat = stat = errno = 0;
+	sock = get_socket(saddr, prot, FALSE, TRUE);
+	if (sock == RPC_ANYSOCK) {
+		if (errno == ETIMEDOUT) {
+			/*
+			 * TCP timeout. Bubble up the error to see 
+			 * how it should be handled.
+			 */
+			rpc_createerr.cf_stat = RPC_TIMEDOUT;
+		}
+		return 0;
+	}
+
+	if (caddr) {
+		/* Get the address of our end of this connection */
+		socklen_t len = sizeof(*caddr);
+		if (getsockname(sock, caddr, &len) != 0)
+			caddr->sin_family = 0;
+	}
+
+	switch(prot) {
+	case IPPROTO_UDP:
+		/* The socket is connected (so we could getsockname successfully),
+		 * but some servers on multi-homed hosts reply from
+		 * the wrong address, so if we stay connected, we lose the reply.
+		 */
+		dissolve.sa_family = AF_UNSPEC;
+		connect(sock, &dissolve, sizeof(dissolve));
+
+		clnt = clntudp_bufcreate(saddr, prog, vers,
+					 RETRY_TIMEOUT, &sock,
+					 RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
+		break;
+	case IPPROTO_TCP:
+		clnt = clnttcp_create(saddr, prog, vers, &sock,
+				      RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
+		break;
+	}
+	if (!clnt) {
+		close(sock);
+		return 0;
+	}
+	memset(&clnt_res, 0, sizeof(clnt_res));
+	stat = clnt_call(clnt, NULLPROC,
+			 (xdrproc_t)xdr_void, (caddr_t)NULL,
+			 (xdrproc_t)xdr_void, (caddr_t)&clnt_res,
+			 TIMEOUT);
+	if (stat) {
+		clnt_geterr(clnt, &rpc_createerr.cf_error);
+		rpc_createerr.cf_stat = stat;
+	}
+	clnt_destroy(clnt);
+	close(sock);
+
+	if (stat == RPC_SUCCESS)
+		return 1;
+	else
+		return 0;
+}
diff --git a/utils/mount/network.h b/utils/mount/network.h
index b3a5525..0f24a32 100644
--- a/utils/mount/network.h
+++ b/utils/mount/network.h
@@ -30,6 +30,9 @@
 int probe_bothports(clnt_addr_t *, clnt_addr_t *);
 int nfs_gethostbyname(const char *, struct sockaddr_in *);
 int nfs_call_umount(clnt_addr_t *, dirpath *);
+int clnt_ping(struct sockaddr_in *, const unsigned long,
+		const unsigned long, const unsigned int,
+		struct sockaddr_in *);
 
 int start_statd(void);
 
diff --git a/utils/mount/nfs4mount.c b/utils/mount/nfs4mount.c
index 26a6896..52b0261 100644
--- a/utils/mount/nfs4mount.c
+++ b/utils/mount/nfs4mount.c
@@ -46,6 +46,7 @@
 #include "nfs4_mount.h"
 #include "nfs_mount.h"
 #include "error.h"
+#include "network.h"
 
 #if defined(VAR_LOCK_DIR)
 #define DEFAULT_DIR VAR_LOCK_DIR