rpc protocol

Signed-off-by: Amar Tumballi <amar@gluster.com>
Signed-off-by: Raghavendra G <raghavendra@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 875 (Implement a new protocol to provide proper backward/forward compatibility)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=875

1 files changed, 189 insertions, 0 deletions

diff --git a/xlators/protocol/rpc/rpc-lib/src/xdr-rpc.c b/xlators/protocol/rpc/rpc-lib/src/xdr-rpc.c
new file mode 100644
index 00000000000..1bcd9bbaa4c
--- /dev/null
+++ b/xlators/protocol/rpc/rpc-lib/src/xdr-rpc.c
@@ -0,0 +1,189 @@
+/*
+  Copyright (c) 2010 Gluster, Inc. <http://www.gluster.com>
+  This file is part of GlusterFS.
+
+  GlusterFS is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published
+  by the Free Software Foundation; either version 3 of the License,
+  or (at your option) any later version.
+
+  GlusterFS is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see
+  <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include <rpc/rpc.h>
+#include <rpc/pmap_clnt.h>
+#include <arpa/inet.h>
+#include <rpc/xdr.h>
+#include <sys/uio.h>
+#include <rpc/auth_unix.h>
+
+#include "mem-pool.h"
+#include "xdr-rpc.h"
+#include "xdr-common.h"
+#include "logging.h"
+
+/* Decodes the XDR format in msgbuf into rpc_msg.
+ * The remaining payload is returned into payload.
+ */
+int
+xdr_to_rpc_call (char *msgbuf, size_t len, struct rpc_msg *call,
+                 struct iovec *payload, char *credbytes, char *verfbytes)
+{
+        XDR                     xdr;
+        char                    opaquebytes[MAX_AUTH_BYTES];
+        struct opaque_auth      *oa = NULL;
+
+        if ((!msgbuf) || (!call))
+                return -1;
+
+        memset (call, 0, sizeof (*call));
+
+        oa = &call->rm_call.cb_cred;
+        if (!credbytes)
+                oa->oa_base = opaquebytes;
+        else
+                oa->oa_base = credbytes;
+
+        oa = &call->rm_call.cb_verf;
+        if (!verfbytes)
+                oa->oa_base = opaquebytes;
+        else
+                oa->oa_base = verfbytes;
+
+        xdrmem_create (&xdr, msgbuf, len, XDR_DECODE);
+        if (!xdr_callmsg (&xdr, call))
+                return -1;
+
+        if (payload) {
+                payload->iov_base = xdr_decoded_remaining_addr (xdr);
+                payload->iov_len = xdr_decoded_remaining_len (xdr);
+        }
+
+        return 0;
+}
+
+
+bool_t
+true_func (XDR *s, caddr_t *a)
+{
+        return TRUE;
+}
+
+
+int
+rpc_fill_empty_reply (struct rpc_msg *reply, uint32_t xid)
+{
+        if (!reply)
+                return -1;
+
+        /* Setting to 0 also results in reply verifier flavor to be
+         * set to AUTH_NULL which is what we want right now.
+         */
+        memset (reply, 0, sizeof (*reply));
+        reply->rm_xid = xid;
+        reply->rm_direction = REPLY;
+
+        return 0;
+}
+
+int
+rpc_fill_denied_reply (struct rpc_msg *reply, int rjstat, int auth_err)
+{
+        if (!reply)
+                return -1;
+
+        reply->rm_reply.rp_stat = MSG_DENIED;
+        reply->rjcted_rply.rj_stat = rjstat;
+        if (rjstat == RPC_MISMATCH) {
+                /* No problem with hardocoding
+                 * RPC version numbers. We only support
+                 * v2 anyway.
+                 */
+                reply->rjcted_rply.rj_vers.low = 2;
+                reply->rjcted_rply.rj_vers.high = 2;
+        } else if (rjstat == AUTH_ERROR)
+                reply->rjcted_rply.rj_why = auth_err;
+
+        return 0;
+}
+
+
+int
+rpc_fill_accepted_reply (struct rpc_msg *reply, int arstat, int proglow,
+                         int proghigh, int verf, int len, char *vdata)
+{
+        if (!reply)
+                return -1;
+
+        reply->rm_reply.rp_stat = MSG_ACCEPTED;
+        reply->acpted_rply.ar_stat = arstat;
+
+        reply->acpted_rply.ar_verf.oa_flavor = verf;
+        reply->acpted_rply.ar_verf.oa_length = len;
+        reply->acpted_rply.ar_verf.oa_base = vdata;
+        if (arstat == PROG_MISMATCH) {
+                reply->acpted_rply.ar_vers.low = proglow;
+                reply->acpted_rply.ar_vers.high = proghigh;
+        } else if (arstat == SUCCESS) {
+
+                /* This is a hack. I'd really like to build a custom
+                 * XDR library because Sun RPC interface is not very flexible.
+                 */
+                reply->acpted_rply.ar_results.proc = (xdrproc_t)true_func;
+                reply->acpted_rply.ar_results.where = NULL;
+        }
+
+        return 0;
+}
+
+int
+rpc_reply_to_xdr (struct rpc_msg *reply, char *dest, size_t len,
+                  struct iovec *dst)
+{
+        XDR             xdr;
+
+        if ((!dest) || (!reply) || (!dst))
+                return -1;
+
+        xdrmem_create (&xdr, dest, len, XDR_ENCODE);
+        if (!xdr_replymsg(&xdr, reply))
+                return -1;
+
+        dst->iov_base = dest;
+        dst->iov_len = xdr_encoded_length (xdr);
+
+        return 0;
+}
+
+
+int
+xdr_to_auth_unix_cred (char *msgbuf, int msglen, struct authunix_parms *au,
+                       char *machname, gid_t *gids)
+{
+        XDR             xdr;
+
+        if ((!msgbuf) || (!machname) || (!gids) || (!au))
+                return -1;
+
+        au->aup_machname = machname;
+        au->aup_gids = gids;
+
+        xdrmem_create (&xdr, msgbuf, msglen, XDR_DECODE);
+
+        if (!xdr_authunix_parms (&xdr, au))
+                return -1;
+
+        return 0;
+}