source4/ntvfs/posix/pvfs_acl_nfs4.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    POSIX NTVFS backend - NT ACLs mapped to NFS4 ACLs, as per
   5    http://www.suse.de/~agruen/nfs4acl/
   6
   7    Copyright (C) Andrew Tridgell 2006
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "vfs_posix.h"
  25 #include "../lib/util/unix_privs.h"
  26 #include "librpc/gen_ndr/ndr_nfs4acl.h"
  27 #include "libcli/security/security.h"
  28
  29 NTSTATUS pvfs_acl_nfs4_init(void);
  30
  31 #define ACE4_IDENTIFIER_GROUP 0x40
  32
  33 /*
  34   load the current ACL from system.nfs4acl
  35 */
  36 static NTSTATUS pvfs_acl_load_nfs4(struct pvfs_state *pvfs, struct pvfs_filename *name, int fd,
  37                                    TALLOC_CTX *mem_ctx,
  38                                    struct security_descriptor **psd)
  39 {
  40         NTSTATUS status;
  41         struct nfs4acl *acl;
  42         struct security_descriptor *sd;
  43         int i, num_ids;
  44         struct id_map *ids;
  45
  46         acl = talloc_zero(mem_ctx, struct nfs4acl);
  47         NT_STATUS_HAVE_NO_MEMORY(acl);
  48
  49         status = pvfs_xattr_ndr_load(pvfs, mem_ctx, name->full_name, fd,
  50                                      NFS4ACL_XATTR_NAME,
  51                                      acl, (void *) ndr_pull_nfs4acl);
  52         if (!NT_STATUS_IS_OK(status)) {
  53                 talloc_free(acl);
  54                 return status;
  55         }
  56
  57         *psd = security_descriptor_initialise(mem_ctx);
  58         NT_STATUS_HAVE_NO_MEMORY(*psd);
  59
  60         sd = *psd;
  61
  62         sd->type |= acl->a_flags;
  63
  64         /* the number of ids to map is the acl count plus uid and gid */
  65         num_ids = acl->a_count +2;
  66         ids = talloc_array(sd, struct id_map, num_ids);
  67         NT_STATUS_HAVE_NO_MEMORY(ids);
  68
  69         ids[0].xid.id = name->st.st_uid;
  70         ids[0].xid.type = ID_TYPE_UID;
  71         ids[0].sid = NULL;
  72         ids[0].status = ID_UNKNOWN;
  73
  74         ids[1].xid.id = name->st.st_gid;
  75         ids[1].xid.type = ID_TYPE_GID;
  76         ids[1].sid = NULL;
  77         ids[1].status = ID_UNKNOWN;
  78
  79         for (i=0;i<acl->a_count;i++) {
  80                 struct nfs4ace *a = &acl->ace[i];
  81                 ids[i+2].xid.id = a->e_id;
  82                 if (a->e_flags & ACE4_IDENTIFIER_GROUP) {
  83                         ids[i+2].xid.type = ID_TYPE_GID;
  84                 } else {
  85                         ids[i+2].xid.type = ID_TYPE_UID;
  86                 }
  87                 ids[i+2].sid = NULL;
  88                 ids[i+2].status = ID_UNKNOWN;
  89         }
  90
  91         /* Allocate memory for the sids from the security descriptor to be on
  92          * the safe side. */
  93         status = wbc_xids_to_sids(pvfs->ntvfs->ctx->event_ctx, ids, num_ids);
  94         NT_STATUS_NOT_OK_RETURN(status);
  95
  96         sd->owner_sid = talloc_steal(sd, ids[0].sid);
  97         sd->group_sid = talloc_steal(sd, ids[1].sid);
  98
  99         for (i=0;i<acl->a_count;i++) {
 100                 struct nfs4ace *a = &acl->ace[i];
 101                 struct security_ace ace;
 102                 ace.type = a->e_type;
 103                 ace.flags = a->e_flags;
 104                 ace.access_mask = a->e_mask;
 105                 ace.trustee = *ids[i+2].sid;
 106                 security_descriptor_dacl_add(sd, &ace);
 107         }
 108
 109         return NT_STATUS_OK;
 110 }
 111
 112 /*
 113   save the acl for a file into system.nfs4acl
 114 */
 115 static NTSTATUS pvfs_acl_save_nfs4(struct pvfs_state *pvfs, struct pvfs_filename *name, int fd,
 116                                    struct security_descriptor *sd)
 117 {
 118         NTSTATUS status;
 119         void *privs;
 120         struct nfs4acl acl;
 121         int i;
 122         TALLOC_CTX *tmp_ctx;
 123         struct id_map *ids;
 124
 125         tmp_ctx = talloc_new(pvfs);
 126         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 127
 128         acl.a_version = 0;
 129         acl.a_flags   = sd->type;
 130         acl.a_count   = sd->dacl?sd->dacl->num_aces:0;
 131         acl.a_owner_mask = 0;
 132         acl.a_group_mask = 0;
 133         acl.a_other_mask = 0;
 134
 135         acl.ace = talloc_array(tmp_ctx, struct nfs4ace, acl.a_count);
 136         if (!acl.ace) {
 137                 talloc_free(tmp_ctx);
 138                 return NT_STATUS_NO_MEMORY;
 139         }
 140
 141         ids = talloc_array(tmp_ctx, struct id_map, acl.a_count);
 142         if (ids == NULL) {
 143                 talloc_free(tmp_ctx);
 144                 return NT_STATUS_NO_MEMORY;
 145         }
 146
 147         for (i=0;i<acl.a_count;i++) {
 148                 struct security_ace *ace = &sd->dacl->aces[i];
 149                 ZERO_STRUCT(ids[i].xid);
 150                 ids[i].sid = dom_sid_dup(ids, &ace->trustee);
 151                 if (ids[i].sid == NULL) {
 152                         talloc_free(tmp_ctx);
 153                         return NT_STATUS_NO_MEMORY;
 154                 }
 155                 ids[i].status = ID_UNKNOWN;
 156         }
 157
 158         status = wbc_sids_to_xids(pvfs->ntvfs->ctx->event_ctx, ids,
 159                                   acl.a_count);
 160         if (!NT_STATUS_IS_OK(status)) {
 161                 talloc_free(tmp_ctx);
 162                 return status;
 163         }
 164
 165         for (i=0;i<acl.a_count;i++) {
 166                 struct nfs4ace *a = &acl.ace[i];
 167                 struct security_ace *ace = &sd->dacl->aces[i];
 168                 a->e_type  = ace->type;
 169                 a->e_flags = ace->flags;
 170                 a->e_mask  = ace->access_mask;
 171                 if (ids[i].xid.type != ID_TYPE_UID) {
 172                         a->e_flags |= ACE4_IDENTIFIER_GROUP;
 173                 }
 174                 a->e_id = ids[i].xid.id;
 175                 a->e_who   = "";
 176         }
 177
 178         privs = root_privileges();
 179         status = pvfs_xattr_ndr_save(pvfs, name->full_name, fd,
 180                                      NFS4ACL_XATTR_NAME,
 181                                      &acl, (void *) ndr_push_nfs4acl);
 182         talloc_free(privs);
 183
 184         talloc_free(tmp_ctx);
 185         return status;
 186 }
 187
 188
 189 /*
 190   initialise pvfs acl NFS4 backend
 191 */
 192 NTSTATUS pvfs_acl_nfs4_init(void)
 193 {
 194         struct pvfs_acl_ops ops = {
 195                 .name = "nfs4acl",
 196                 .acl_load = pvfs_acl_load_nfs4,
 197                 .acl_save = pvfs_acl_save_nfs4
 198         };
 199         return pvfs_acl_register(&ops);
 200 }