timestamps: setattr uses attributes cansettime,time_delta

added time_delta argument to xdr_settime4().  if the normal 'time' argument is within time_delta of the current time (get_nfs_time()), it uses time_how=SET_TO_SERVER_TIME4.  otherwise, it uses SET_TO_CLIENT_TIME4 and encodes the time as usual

handle_nfs41_setattr() ignores times if superblock->cansettime==0.  otherwise, it passes in superblock->time_delta (via info.time_delta) along with the other time attributes, for use with xdr_settime4()

Signed-off-by: Casey Bodley <cbodley@umich.edu>

daemon/nfs41_xdr.c

@@ -27,8 +27,10 @@
 #include "nfs41_compound.h"
 #include "nfs41_ops.h"
 #include "nfs41_xdr.h"
+#include "util.h"
 #include "daemon_debug.h"
 
+
 static bool_t encode_file_attrs(
     fattr4 *attrs,
     nfs41_file_info *info);
@@ -95,22 +97,38 @@ static bool_t xdr_nfstime4(
 
 
 /* settime4 */
+static uint32_t settime_how(
+    nfstime4 *newtime,
+    const nfstime4 *time_delta)
+{
+    nfstime4 current;
+    get_nfs_time(&current);
+    /* get the absolute difference between current and newtime */
+    nfstime_diff(&current, newtime, &current);
+    nfstime_abs(&current, &current);
+    /* compare the difference with time_delta */
+    nfstime_diff(time_delta, &current, &current);
+    /* use client time if diff > delta (i.e. time_delta - current < 0) */
+    return current.seconds < 0 ? SET_TO_CLIENT_TIME4 : SET_TO_SERVER_TIME4;
+}
+
 static bool_t xdr_settime4(
     XDR *xdr,
-    nfstime4 *nt)
+    nfstime4 *nt,
+    const nfstime4 *time_delta)
 {
-    if (xdr->x_op == XDR_ENCODE) {
+    uint32_t how = settime_how(nt, time_delta);
-        uint32_t send_value = SET_TO_CLIENT_TIME4;
+
-        if (!xdr_u_int32_t(xdr, &send_value))
+    if (xdr->x_op != XDR_ENCODE) /* not used for decode */
-            return FALSE;
-    } else if (xdr->x_op == XDR_DECODE) {
-        uint32_t ignored_value;
-        if (!xdr_u_int32_t(xdr, &ignored_value))
-            return FALSE;
-    } else
         return FALSE;
 
+    if (!xdr_u_int32_t(xdr, &how))
+        return FALSE;
+
+    if (how == SET_TO_CLIENT_TIME4)
         return xdr_nfstime4(xdr, nt);
+
+    return TRUE;
 }
 
 /* stateid4 */
@@ -2334,7 +2352,7 @@ static bool_t encode_file_attrs(
             attrs->attrmask.arr[1] |= FATTR4_WORD1_MODE;
         }
         if (info->attrmask.arr[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
-            if (!xdr_settime4(&localxdr, &info->time_access))
+            if (!xdr_settime4(&localxdr, &info->time_access, info->time_delta))
                 return FALSE;
             attrs->attrmask.arr[1] |= FATTR4_WORD1_TIME_ACCESS_SET;
         }
@@ -2344,7 +2362,7 @@ static bool_t encode_file_attrs(
             attrs->attrmask.arr[1] |= FATTR4_WORD1_TIME_CREATE;
         }
         if (info->attrmask.arr[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
-            if (!xdr_settime4(&localxdr, &info->time_modify))
+            if (!xdr_settime4(&localxdr, &info->time_modify, info->time_delta))
                 return FALSE;
             attrs->attrmask.arr[1] |= FATTR4_WORD1_TIME_MODIFY_SET;
         }

daemon/setattr.c

@@ -98,12 +98,12 @@ static void remove_unsupported_attrs(
 
 static int handle_nfs41_setattr(setattr_upcall_args *args)
 {
-    int status;
     PFILE_BASIC_INFO basic_info = (PFILE_BASIC_INFO)args->buf;
     nfs41_open_state *state = args->state;
     nfs41_superblock *superblock = state->file.fh.superblock;
     stateid4 stateid, *pstateid;
     nfs41_file_info info;
+    int status = NO_ERROR;
 
     pstateid = nfs41_lock_stateid_copy(&state->last_lock, &stateid);
     if (pstateid == NULL)
@@ -115,24 +115,35 @@ static int handle_nfs41_setattr(setattr_upcall_args *args)
     info.hidden = basic_info->FileAttributes & FILE_ATTRIBUTE_HIDDEN ? 1 : 0;
     info.attrmask.arr[0] |= FATTR4_WORD0_HIDDEN;
     info.attrmask.count = 1;
+
+    if (superblock->cansettime) {
+        /* set the time_delta so xdr_settime4() can decide
+         * whether or not to use SET_TO_SERVER_TIME4 */
+        info.time_delta = &superblock->time_delta;
+
         /* time_create */
         if (basic_info->CreationTime.QuadPart > 0) {
-        file_time_to_nfs_time(&basic_info->CreationTime, &info.time_create);
+            file_time_to_nfs_time(&basic_info->CreationTime,
+                &info.time_create);
             info.attrmask.arr[1] |= FATTR4_WORD1_TIME_CREATE;
             info.attrmask.count = 2;
         }
         /* time_access_set */
         if (basic_info->LastAccessTime.QuadPart > 0) {
-        file_time_to_nfs_time(&basic_info->LastAccessTime, &info.time_access);
+            file_time_to_nfs_time(&basic_info->LastAccessTime,
+                &info.time_access);
             info.attrmask.arr[1] |= FATTR4_WORD1_TIME_ACCESS_SET;
             info.attrmask.count = 2;
         }
         /* time_modify_set */
         if (basic_info->LastWriteTime.QuadPart > 0) {
-        file_time_to_nfs_time(&basic_info->LastWriteTime, &info.time_modify);
+            file_time_to_nfs_time(&basic_info->LastWriteTime,
+                &info.time_modify);
             info.attrmask.arr[1] |= FATTR4_WORD1_TIME_MODIFY_SET;
             info.attrmask.count = 2;
         }
+    }
+
     /* mode */
     if (basic_info->FileAttributes & FILE_ATTRIBUTE_READONLY) {
         info.mode = 0444;
@@ -140,19 +151,22 @@ static int handle_nfs41_setattr(setattr_upcall_args *args)
         info.attrmask.count = 2;
     }
 
+    /* only ask for attributes that are supported by the filesystem */
     AcquireSRWLockShared(&superblock->lock);
     remove_unsupported_attrs(&superblock->supported_attrs, &info.attrmask);
     ReleaseSRWLockShared(&superblock->lock);
 
     if (!info.attrmask.count)
-        return 0;
+        goto out;
 
     status = nfs41_setattr(state->session, &state->file, pstateid, &info);
-    if (status)
+    if (status) {
         dprintf(1, "nfs41_setattr() failed with error %s.\n",
             nfs_error_string(status));
-
+        status = nfs_to_windows_error(status, ERROR_NOT_SUPPORTED);
-    return nfs_to_windows_error(status, ERROR_NOT_SUPPORTED);
+    }
+out:
+    return status;
 }
 
 static int handle_nfs41_remove(setattr_upcall_args *args)