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     no_map_access,                /* map_access */
  64     symlink_lookup_name,          /* lookup_name */
  65     no_close_handle,              /* close_handle */
  66     symlink_destroy               /* destroy */
  67 };
  68
  69 static void symlink_dump( struct object *obj, int verbose )
  70 {
  71     struct symlink *symlink = (struct symlink *)obj;
  72     assert( obj->ops == &symlink_ops );
  73
  74     fprintf( stderr, "Symlink " );
  75     dump_object_name( obj );
  76     fprintf( stderr, " -> L\"" );
  77     dump_strW( symlink->target, symlink->len / sizeof(WCHAR), stderr, "\"\"" );
  78     fprintf( stderr, "\"\n" );
  79 }
  80
  81 static struct object *symlink_lookup_name( struct object *obj, struct unicode_str *name,
  82                                            unsigned int attr )
  83 {
  84     struct symlink *symlink = (struct symlink *)obj;
  85     struct unicode_str target_str, name_left;
  86     struct object *target;
  87
  88     assert( obj->ops == &symlink_ops );
  89     if (attr & OBJ_OPENLINK) return NULL;
  90
  91     target_str.str = symlink->target;
  92     target_str.len = symlink->len;
  93     if ((target = find_object_dir( NULL, &target_str, attr, &name_left )))
  94     {
  95         if (name_left.len)
  96         {
  97             release_object( target );
  98             target = NULL;
  99             set_error( STATUS_OBJECT_PATH_NOT_FOUND );
 100         }
 101     }
 102     return target;
 103 }
 104
 105 static void symlink_destroy( struct object *obj )
 106 {
 107     struct symlink *symlink = (struct symlink *)obj;
 108     assert( obj->ops == &symlink_ops );
 109     free( symlink->target );
 110 }
 111
 112 struct symlink *create_symlink( struct directory *root, const struct unicode_str *name,
 113                                 unsigned int attr, const struct unicode_str *target )
 114 {
 115     struct symlink *symlink;
 116
 117     if (!target->len)
 118     {
 119         set_error( STATUS_INVALID_PARAMETER );
 120         return NULL;
 121     }
 122     if ((symlink = create_named_object_dir( root, name, attr, &symlink_ops )) &&
 123         (get_error() != STATUS_OBJECT_NAME_EXISTS))
 124     {
 125         if ((symlink->target = memdup( target->str, target->len )))
 126             symlink->len = target->len;
 127         else
 128         {
 129             release_object( symlink );
 130             symlink = NULL;
 131         }
 132     }
 133     return symlink;
 134 }
 135
 136
 137 /* create a symbolic link object */
 138 DECL_HANDLER(create_symlink)
 139 {
 140     struct symlink *symlink;
 141     struct unicode_str name, target;
 142     struct directory *root = NULL;
 143
 144     if (req->name_len > get_req_data_size())
 145     {
 146         set_error( STATUS_INVALID_PARAMETER );
 147         return;
 148     }
 149     name.str   = get_req_data();
 150     target.str = name.str + req->name_len / sizeof(WCHAR);
 151     name.len   = (target.str - name.str) * sizeof(WCHAR);
 152     target.len = ((get_req_data_size() - name.len) / sizeof(WCHAR)) * sizeof(WCHAR);
 153
 154     if (req->rootdir && !(root = get_directory_obj( current->process, req->rootdir, 0 )))
 155         return;
 156
 157     if ((symlink = create_symlink( root, &name, req->attributes, &target )))
 158     {
 159         reply->handle = alloc_handle( current->process, symlink, req->access, req->attributes );
 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     struct symlink *symlink;
 172
 173     get_req_unicode_str( &name );
 174     if (req->rootdir && !(root = get_directory_obj( current->process, req->rootdir, 0 )))
 175         return;
 176
 177     if ((symlink = open_object_dir( root, &name, req->attributes | OBJ_OPENLINK, &symlink_ops )))
 178     {
 179         reply->handle = alloc_handle( current->process, &symlink->obj, req->access, req->attributes );
 180         release_object( symlink );
 181     }
 182
 183     if (root) release_object( root );
 184 }
 185
 186 /* query a symbolic link object */
 187 DECL_HANDLER(query_symlink)
 188 {
 189     struct symlink *symlink;
 190
 191     symlink = (struct symlink *)get_handle_obj( current->process, req->handle,
 192                                                 SYMBOLIC_LINK_QUERY, &symlink_ops );
 193     if (!symlink) return;
 194
 195     if (get_reply_max_size() < symlink->len)
 196         set_error( STATUS_BUFFER_TOO_SMALL );
 197     else
 198         set_reply_data( symlink->target, symlink->len );
 199     release_object( symlink );
 200 }