server/symlink.c

   1 /*
   2  * Server-side symbolic link object management
   3  *
   4  * Copyright (C) 2005 Vitaliy Margolen
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include "config.h"
  23 #include "wine/port.h"
  24
  25 #include <assert.h>
  26 #include <stdarg.h>
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <sys/types.h>
  30
  31 #include "ntstatus.h"
  32 #define WIN32_NO_STATUS
  33 #include "winternl.h"
  34 #include "ddk/wdm.h"
  35
  36 #include "handle.h"
  37 #include "request.h"
  38 #include "object.h"
  39 #include "unicode.h"
  40
  41 struct symlink
  42 {
  43     struct object    obj;       /* object header */
  44     WCHAR           *target;    /* target of the symlink */
  45     size_t           len;       /* target len in bytes */
  46 };
  47
  48 static void symlink_dump( struct object *obj, int verbose );
  49 static struct object *symlink_lookup_name( struct object *obj, struct unicode_str *name,
  50                                            unsigned int attr );
  51 static void symlink_destroy( struct object *obj );
  52
  53 static const struct object_ops symlink_ops =
  54 {
  55     sizeof(struct symlink),       /* size */
  56     symlink_dump,                 /* dump */
  57     no_add_queue,                 /* add_queue */
  58     NULL,                         /* remove_queue */
  59     NULL,                         /* signaled */
  60     NULL,                         /* satisfied */
  61     no_signal,                    /* signal */
  62     no_get_fd,                    /* get_fd */
  63     symlink_lookup_name,          /* lookup_name */
  64     no_close_handle,              /* close_handle */
  65     symlink_destroy               /* destroy */
  66 };
  67
  68 static void symlink_dump( struct object *obj, int verbose )
  69 {
  70     struct symlink *symlink = (struct symlink *)obj;
  71     assert( obj->ops == &symlink_ops );
  72
  73     fprintf( stderr, "Symlink " );
  74     dump_object_name( obj );
  75     fprintf( stderr, " -> L\"" );
  76     dump_strW( symlink->target, symlink->len / sizeof(WCHAR), stderr, "\"\"" );
  77     fprintf( stderr, "\"\n" );
  78 }
  79
  80 static struct object *symlink_lookup_name( struct object *obj, struct unicode_str *name,
  81                                            unsigned int attr )
  82 {
  83     struct symlink *symlink = (struct symlink *)obj;
  84     struct unicode_str target_str, name_left;
  85     struct object *target;
  86
  87     assert( obj->ops == &symlink_ops );
  88     if (attr & OBJ_OPENLINK) return NULL;
  89
  90     target_str.str = symlink->target;
  91     target_str.len = symlink->len;
  92     if ((target = find_object_dir( NULL, &target_str, attr, &name_left )))
  93     {
  94         if (name_left.len)
  95         {
  96             release_object( target );
  97             target = NULL;
  98             set_error( STATUS_OBJECT_PATH_NOT_FOUND );
  99         }
 100     }
 101     return target;
 102 }
 103
 104 static void symlink_destroy( struct object *obj )
 105 {
 106     struct symlink *symlink = (struct symlink *)obj;
 107     assert( obj->ops == &symlink_ops );
 108     free( symlink->target );
 109 }
 110
 111 struct symlink *create_symlink( struct directory *root, const struct unicode_str *name,
 112                                 unsigned int attr, const struct unicode_str *target )
 113 {
 114     struct symlink *symlink;
 115
 116     if (!target->len)
 117     {
 118         set_error( STATUS_INVALID_PARAMETER );
 119         return NULL;
 120     }
 121     if ((symlink = create_named_object_dir( root, name, attr, &symlink_ops )) &&
 122         (get_error() != STATUS_OBJECT_NAME_EXISTS))
 123     {
 124         if ((symlink->target = memdup( target->str, target->len )))
 125             symlink->len = target->len;
 126         else
 127         {
 128             release_object( symlink );
 129             symlink = NULL;
 130         }
 131     }
 132     return symlink;
 133 }
 134
 135
 136 /* create a symbolic link object */
 137 DECL_HANDLER(create_symlink)
 138 {
 139     struct symlink *symlink;
 140     struct unicode_str name, target;
 141     struct directory *root = NULL;
 142
 143     if (req->name_len > get_req_data_size())
 144     {
 145         set_error( STATUS_INVALID_PARAMETER );
 146         return;
 147     }
 148     name.str   = get_req_data();
 149     target.str = name.str + req->name_len / sizeof(WCHAR);
 150     name.len   = (target.str - name.str) * sizeof(WCHAR);
 151     target.len = ((get_req_data_size() - name.len) / sizeof(WCHAR)) * sizeof(WCHAR);
 152
 153     if (req->rootdir && !(root = get_directory_obj( current->process, req->rootdir, 0 )))
 154         return;
 155
 156     if ((symlink = create_symlink( root, &name, req->attributes, &target )))
 157     {
 158         reply->handle = alloc_handle( current->process, symlink, req->access,
 159                                       req->attributes & OBJ_INHERIT );
 160         release_object( symlink );
 161     }
 162
 163     if (root) release_object( root );
 164 }
 165
 166 /* open a symbolic link object */
 167 DECL_HANDLER(open_symlink)
 168 {
 169     struct unicode_str name;
 170     struct directory *root = NULL;
 171
 172     get_req_unicode_str( &name );
 173     if (req->rootdir && !(root = get_directory_obj( current->process, req->rootdir, 0 )))
 174         return;
 175
 176     reply->handle = open_object_dir( root, &name, req->attributes | OBJ_OPENLINK,
 177                                      &symlink_ops, req->access );
 178
 179     if (root) release_object( root );
 180 }
 181
 182 /* query a symbolic link object */
 183 DECL_HANDLER(query_symlink)
 184 {
 185     struct symlink *symlink;
 186
 187     symlink = (struct symlink *)get_handle_obj( current->process, req->handle,
 188                                                 SYMBOLIC_LINK_QUERY, &symlink_ops );
 189     if (!symlink) return;
 190
 191     if (get_reply_max_size() < symlink->len)
 192         set_error( STATUS_BUFFER_TOO_SMALL );
 193     else
 194         set_reply_data( symlink->target, symlink->len );
 195     release_object( symlink );
 196 }