msnfs41client: Patches to implement |FileNormalizedNameInformation| support+NFS traffic watcher script subcmd, 2025-02-27
Posted by Anonymous on Thu 27th Feb 2025 13:45
raw | new post

From 2dcf3e2806282633000d55e626ba4526c86dc077 Mon Sep 17 00:00:00 2001
From: Roland Mainz <roland.mainz@nrubsig.org>
Date: Thu, 27 Feb 2025 13:13:50 +0100
Subject: [PATCH 1/2] sys: Implement |FileNormalizedNameInformation|

Implement support for |FileNormalizedNameInformation|, assuming we do
not build 8.3 filename support (which we do not have) and the exported
NFS filesystem is case-sensitive.

Signed-off-by: Cedric Blancher <cedric.blancher@gmail.com>
---
 sys/nfs41sys_fileinfo.c | 60 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/sys/nfs41sys_fileinfo.c b/sys/nfs41sys_fileinfo.c
index 5f59d7d..c8ae273 100644
--- a/sys/nfs41sys_fileinfo.c
+++ b/sys/nfs41sys_fileinfo.c
@@ -220,6 +220,66 @@ NTSTATUS nfs41_QueryFileInformation(
 #endif

     switch (InfoClass) {
+#ifdef NFS41_DRIVER_DISABLE_8DOT3_SHORTNAME_GENERATION
+    /*
+     * |FileNormalizedNameInformation| is specified to return an
+     * absolute pathname where each short name component (e.g. 8.3
+     * file name) has been replaced with the corresponding long
+     * name component, and each name component uses the exact
+     * letter casing stored on disk.
+     *
+     * So if we do not support 8.3 names (i.e.
+     * |NFS41_DRIVER_DISABLE_8DOT3_SHORTNAME_GENERATION| being
+     * defined) and the exported NFS filesystem is case-sensitive,
+     * then just handle |FileNormalizedNameInformation| like
+     * |FileNameInformation|.
+     */
+    case FileNormalizedNameInformation:
+    {
+        ULONG fsattrs = pVNetRootContext->FsAttrs.FileSystemAttributes;
+
+        /*
+         * FIXME: If the underlying filesystem is case-insensitive we
+         * would have to make an upcall to fetch the exact casing
+         * from our namecache or the NFS server.
+         */
+        if ((fsattrs & FILE_CASE_SENSITIVE_SEARCH) == 0) {
+            print_error("nfs41_QueryFileInformation: "
+                "FileNormalizedNameInformation not supported for "
+                "case-insensitive filesystems\n");
+            status = STATUS_NOT_SUPPORTED;
+            goto out;
+        }
+
+        if (RxContext->Info.LengthRemaining <
+            FIELD_OFFSET(FILE_NAME_INFORMATION, FileName)) {
+            RxContext->Info.Length = 0;
+            status = STATUS_BUFFER_OVERFLOW;
+            goto out;
+        }
+
+        PFILE_NAME_INFORMATION nameinfo =
+            (PFILE_NAME_INFORMATION)RxContext->Info.Buffer;
+        RxContext->Info.LengthRemaining -=
+            FIELD_OFFSET(FILE_NAME_INFORMATION, FileName);
+
+        RxConjureOriginalName((PFCB)RxContext->pFcb,
+            (PFOBX)RxContext->pFobx,
+            &nameinfo->FileNameLength,
+            &nameinfo->FileName[0],
+            &RxContext->Info.Length,
+            VNetRoot_As_UNC_Name);
+
+        if (RxContext->Info.LengthRemaining < 0) {
+            RxContext->Info.Length = 0;
+            status = STATUS_BUFFER_OVERFLOW;
+            goto out;
+        }
+
+        status = STATUS_SUCCESS;
+        goto out;
+    }
+#endif /* NFS41_DRIVER_DISABLE_8DOT3_SHORTNAME_GENERATION */
     case FileEaInformation:
     {
         if (RxContext->Info.LengthRemaining <
--
2.45.1

From a8c2d216b63d80e03c76d5f957716cb4f40ae385 Mon Sep 17 00:00:00 2001
From: Roland Mainz <roland.mainz@nrubsig.org>
Date: Thu, 27 Feb 2025 14:28:39 +0100
Subject: [PATCH 2/2] cygwin: Add msnfs41client subcmd "watch_nfs_traffic" to
 watch NFS traffic

Add msnfs41client.bash subcmd "watch_nfs_traffic" to watch NFS network
traffic.
Requires "tshark" utility from WireShark.

Signed-off-by: Cedric Blancher <cedric.blancher@gmail.com>
---
 cygwin/README.bintarball.txt    | 11 ++++++----
 cygwin/devel/msnfs41client.bash | 39 +++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/cygwin/README.bintarball.txt b/cygwin/README.bintarball.txt
index 76ec183..407576a 100644
--- a/cygwin/README.bintarball.txt
+++ b/cygwin/README.bintarball.txt
@@ -680,10 +680,13 @@ $ mount -t drvfs '\0.49.202.230@2049\nfs4\bigdisk' /mnt/bigdisk
   to be installed.

 - Watching network traffic:
-  WireShark has a command line tool called "tshark", which can be used
-  to see NFSv4 traffic. As NFSv4 uses RPC you have to filter for RPC,
-  and the RPC filter automatically identifies NFSv4 traffic on it's RPC
-  id.
+  - Use $ /sbin/msnfs41client watch_nfs_traffic # to watch the
+  NFS network traffic
+
+  - WireShark has a command line tool called "tshark", which can be
+  used to see NFSv4 traffic. As NFSv4 uses RPC you have to filter for
+  RPC, and the RPC filter automatically identifies NFSv4 traffic on
+  it's RPC id.
   Example for Windows:
   (for NFSv4 default TCP port "2049", replace "2049" with the
   desired port if you use a custom port ; use "ipconfig" to find the
diff --git a/cygwin/devel/msnfs41client.bash b/cygwin/devel/msnfs41client.bash
index b12eb1e..42b4a86 100755
--- a/cygwin/devel/msnfs41client.bash
+++ b/cygwin/devel/msnfs41client.bash
@@ -726,6 +726,35 @@ function watch_kernel_debuglog
        return 0
 }

+function watch_nfs_traffic
+{
+       typeset -i nfsv4port=2049
+       typeset s
+       typeset -a eth_interface_list=()
+
+       printf '# %s: Reading ethernet interface list\n' "$0"
+       while read s ; do
+               eth_interface_list+=( "${s/$'\r'/}" )
+       done < <(powershell -Command 'Get-NetAdapter -Physical | Where-Object { $_.Status -eq "Up"} | ForEach-Object {$_.Name}')
+
+       printf '# Found interface %q\n' "${eth_interface_list[@]}"
+
+       # args to watch NFSv4.x RFC traffic
+       typeset -a tshark_args=(
+               '-f' "port $nfsv4port"
+               '-d' "tcp.port==${nfsv4port},rpc"
+       )
+
+       # add ethernet interface names
+       for s in "${eth_interface_list[@]}" ; do
+               tshark_args+=( '-i' "$s" )
+       done
+
+       '/cygdrive/c/Program Files/Wireshark/tshark' "${tshark_args[@]}"
+
+       return 0
+}
+
 function nfsclient_system_mount_globaldirs
 {
        set -o xtrace
@@ -1024,6 +1053,16 @@ function main
                        watch_kernel_debuglog
                        return $?
                        ;;
+               'watch_nfs_traffic')
+                       check_machine_arch || (( numerr++ ))
+                       require_cmd 'powershell' || (( numerr++ ))
+                       require_cmd '/cygdrive/c/Program Files/Wireshark/tshark' || (( numerr++ ))
+
+                       (( numerr > 0 )) && return 1
+
+                       watch_nfs_traffic
+                       return $?
+                       ;;
                'sys_terminal')
                        check_machine_arch || (( numerr++ ))
                        require_cmd 'mintty.exe' || (( numerr++ ))
--
2.45.1