protocol/server: do not do root-squashing for trusted clients

* As of now clients mounting within the storage pool using that machine's
  ip/hostname are trusted clients (i.e clients local to the glusterd).

* Be careful when the request itself comes in as nfsnobody (ex: posix tests).
  So move the squashing part to protocol/server when it creates a new frame
  for the request, instead of auth part of rpc layer.

* For nfs servers do root-squashing without checking if it is trusted client,
  as all the nfs servers would be running within the storage pool, hence will
  be trusted clients for the bricks.

* Provide one more option for mounting which actually says root-squash
  should/should not happen. This value is given priority only for the trusted
  clients. For non trusted clients, the volume option takes the priority. But
  for trusted clients if root-squash should not happen, then they have to be
  mounted with root-squash=no option. (This is done because by default
  blocking root-squashing for the trusted clients will cause problems for smb
  and UFO clients for which the requests have to be squashed if the option is
  enabled).

* For geo-replication and defrag clients do not do root-squashing.

* Introduce a new option in open-behind for doing read after successful open.

Change-Id: I8a8359840313dffc34824f3ea80a9c48375067f0
BUG: 954057
Signed-off-by: Raghavendra Bhat <raghavendra@redhat.com>
Reviewed-on: http://review.gluster.org/4863
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

3 files changed, 42 insertions, 1 deletions

diff --git a/xlators/mount/fuse/src/fuse-bridge.c b/xlators/mount/fuse/src/fuse-bridge.c
index 315259ece7b..d9055468e43 100644
--- a/xlators/mount/fuse/src/fuse-bridge.c
+++ b/xlators/mount/fuse/src/fuse-bridge.c
@@ -5323,6 +5323,18 @@ init (xlator_t *this_xl)
         GF_OPTION_INIT ("congestion-threshold", priv->congestion_threshold,
                         int32, cleanup_exit);
 
+        GF_OPTION_INIT("no-root-squash", priv->no_root_squash, bool,
+                       cleanup_exit);
+        /* change the client_pid to no-root-squash pid only if the
+           client is none of defrag process, hadoop access and gsyncd process.
+        */
+        if (!priv->client_pid_set) {
+                if (priv->no_root_squash == _gf_true) {
+                        priv->client_pid_set = _gf_true;
+                        priv->client_pid = GF_CLIENT_PID_NO_ROOT_SQUASH;
+                }
+        }
+
         /* user has set only background-qlen, not congestion-threshold,
            use the fuse kernel driver formula to set congestion. ie, 75% */
         if (dict_get (this_xl->options, "background-qlen") &&
@@ -5563,5 +5575,15 @@ struct volume_options options[] = {
           .type = GF_OPTION_TYPE_BOOL,
           .default_value = "yes"
         },
+        { .key = {"no-root-squash"},
+          .type = GF_OPTION_TYPE_BOOL,
+          .default_value = "false",
+          .description = "This is the mount option for disabling the "
+          "root squash for the client irrespective of whether the root-squash "
+          "option for the volume is set or not. But this option is honoured "
+          "only for the trusted clients. For non trusted clients this value "
+          "does not have any affect and the volume option for root-squash is "
+          "honoured.",
+        },
         { .key = {NULL} },
 };
diff --git a/xlators/mount/fuse/src/fuse-bridge.h b/xlators/mount/fuse/src/fuse-bridge.h
index 34794b6ea45..f1c4cb3f0d8 100644
--- a/xlators/mount/fuse/src/fuse-bridge.h
+++ b/xlators/mount/fuse/src/fuse-bridge.h
@@ -104,6 +104,14 @@ struct fuse_private {
 	int32_t	             fopen_keep_cache;
 	int32_t		     gid_cache_timeout;
         gf_boolean_t         enable_ino32;
+        /* This is the mount option for disabling the root-squash for the
+           mount irrespective of whether the root-squash option for the
+           volume is set or not. But this option is honoured only for
+           thr trusted clients. For non trusted clients this value does
+           not have any affect and the volume option for root-squash is
+           honoured.
+        */
+        gf_boolean_t        no_root_squash;
         fdtable_t           *fdtable;
 	gid_cache_t	     gid_cache;
         char                *fuse_mountopts;
diff --git a/xlators/mount/fuse/utils/mount.glusterfs.in b/xlators/mount/fuse/utils/mount.glusterfs.in
index ff6b524605a..d22f6a69b1e 100755
--- a/xlators/mount/fuse/utils/mount.glusterfs.in
+++ b/xlators/mount/fuse/utils/mount.glusterfs.in
@@ -171,7 +171,11 @@ start_glusterfs ()
         cmd_line=$(echo "$cmd_line --aux-gfid-mount");
     fi
 
-    # options with values start here
+    if [ -n "$no_root_squash" ]; then
+        cmd_line=$(echo "$cmd_line --no-root-squash");
+    fi
+
+#options with values start here
     if [ -n "$log_level" ]; then
         cmd_line=$(echo "$cmd_line --log-level=$log_level");
     fi
@@ -442,6 +446,13 @@ with_options()
         "use-readdirp")
             use_readdirp=$value
             ;;
+        "root-squash")
+            if [ $value == "no" ] ||
+                [ $value == "off" ] ||
+                [ $value == "disable" ] ||
+                [ $value == "false" ] ; then
+                no_root_squash=1;
+            fi ;;
         *)
             echo "Invalid option: $key"
             exit 0