source4/ntptr/ntptr_base.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    NTPTR base code
   5
   6    Copyright (C) Stefan (metze) Metzmacher 2005
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21 /*
  22   this implements the core code for all NTPTR modules. Backends register themselves here.
  23 */
  24
  25 #include "includes.h"
  26 #include "ntptr/ntptr.h"
  27 #include "param/param.h"
  28
  29 /* the list of currently registered NTPTR backends */
  30 static struct ntptr_backend {
  31         const struct ntptr_ops *ops;
  32 } *backends = NULL;
  33 static int num_backends;
  34
  35 /*
  36   register a NTPTR backend.
  37
  38   The 'name' can be later used by other backends to find the operations
  39   structure for this backend.
  40 */
  41 NTSTATUS ntptr_register(const void *_ops)
  42 {
  43         const struct ntptr_ops *ops = _ops;
  44         struct ntptr_ops *new_ops;
  45
  46         if (ntptr_backend_byname(ops->name) != NULL) {
  47                 /* its already registered! */
  48                 DEBUG(0,("NTPTR backend '%s' already registered\n",
  49                          ops->name));
  50                 return NT_STATUS_OBJECT_NAME_COLLISION;
  51         }
  52
  53         backends = realloc_p(backends, struct ntptr_backend, num_backends+1);
  54         if (!backends) {
  55                 smb_panic("out of memory in ntptr_register");
  56         }
  57
  58         new_ops = smb_xmemdup(ops, sizeof(*ops));
  59         new_ops->name = smb_xstrdup(ops->name);
  60
  61         backends[num_backends].ops = new_ops;
  62
  63         num_backends++;
  64
  65         DEBUG(3,("NTPTR backend '%s'\n",
  66                  ops->name));
  67
  68         return NT_STATUS_OK;
  69 }
  70
  71 NTSTATUS ntptr_init(struct loadparm_context *lp_ctx)
  72 {
  73 #define _MODULE_PROTO(init) extern NTSTATUS init(void);
  74         STATIC_ntptr_MODULES_PROTO;
  75         init_module_fn static_init[] = { STATIC_ntptr_MODULES };
  76         init_module_fn *shared_init = load_samba_modules(NULL, lp_ctx, "ntptr");
  77
  78         run_init_functions(static_init);
  79         run_init_functions(shared_init);
  80
  81         talloc_free(shared_init);
  82
  83         return NT_STATUS_OK;
  84 }
  85
  86
  87 /*
  88   return the operations structure for a named backend
  89 */
  90 const struct ntptr_ops *ntptr_backend_byname(const char *name)
  91 {
  92         int i;
  93
  94         for (i=0;i<num_backends;i++) {
  95                 if (strcmp(backends[i].ops->name, name) == 0) {
  96                         return backends[i].ops;
  97                 }
  98         }
  99
 100         return NULL;
 101 }
 102
 103
 104 /*
 105   return the NTPTR interface version, and the size of some critical types
 106   This can be used by backends to either detect compilation errors, or provide
 107   multiple implementations for different smbd compilation options in one module
 108 */
 109 static const struct ntptr_critical_sizes critical_sizes = {
 110         .interface_version              = NTPTR_INTERFACE_VERSION,
 111         .sizeof_ntptr_critical_sizes    = sizeof(struct ntptr_critical_sizes),
 112         .sizeof_ntptr_context           = sizeof(struct ntptr_context),
 113         .sizeof_ntptr_ops               = sizeof(struct ntptr_ops),
 114 };
 115 const struct ntptr_critical_sizes *ntptr_interface_version(void)
 116 {
 117         return &critical_sizes;
 118 }
 119
 120 /*
 121   create a ntptr_context with a specified NTPTR backend
 122 */
 123 NTSTATUS ntptr_init_context(TALLOC_CTX *mem_ctx, struct tevent_context *ev_ctx,
 124                             struct loadparm_context *lp_ctx,
 125                             const char *providor, struct ntptr_context **_ntptr)
 126 {
 127         NTSTATUS status;
 128         struct ntptr_context *ntptr;
 129
 130         if (!providor) {
 131                 return NT_STATUS_INTERNAL_ERROR;
 132         }
 133
 134         ntptr = talloc(mem_ctx, struct ntptr_context);
 135         NT_STATUS_HAVE_NO_MEMORY(ntptr);
 136         ntptr->private_data     = NULL;
 137         ntptr->ops              = ntptr_backend_byname(providor);
 138         ntptr->ev_ctx           = ev_ctx;
 139         ntptr->lp_ctx           = lp_ctx;
 140
 141         if (!ntptr->ops) {
 142                 DEBUG(1,("ntptr_init_context: failed to find NTPTR providor='%s'\n",
 143                          providor));
 144                 return NT_STATUS_INTERNAL_ERROR;
 145         }
 146
 147         status = ntptr->ops->init_context(ntptr);
 148         NT_STATUS_NOT_OK_RETURN(status);
 149
 150         *_ntptr = ntptr;
 151         return NT_STATUS_OK;
 152 }