source4/auth/gensec/schannel.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    dcerpc schannel operations
   5
   6    Copyright (C) Andrew Tridgell 2004
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   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 "librpc/gen_ndr/ndr_schannel.h"
  25 #include "auth/auth.h"
  26 #include "auth/credentials/credentials.h"
  27 #include "auth/gensec/gensec.h"
  28 #include "auth/gensec/gensec_proto.h"
  29 #include "auth/gensec/schannel.h"
  30 #include "auth/gensec/schannel_state.h"
  31 #include "auth/gensec/schannel_proto.h"
  32 #include "librpc/rpc/dcerpc.h"
  33 #include "param/param.h"
  34 #include "auth/session_proto.h"
  35
  36 static size_t schannel_sig_size(struct gensec_security *gensec_security, size_t data_size)
  37 {
  38         return 32;
  39 }
  40
  41 static NTSTATUS schannel_session_key(struct gensec_security *gensec_security,
  42                                             DATA_BLOB *session_key)
  43 {
  44         return NT_STATUS_NOT_IMPLEMENTED;
  45 }
  46
  47 static NTSTATUS schannel_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
  48                                        const DATA_BLOB in, DATA_BLOB *out)
  49 {
  50         struct schannel_state *state = (struct schannel_state *)gensec_security->private_data;
  51         NTSTATUS status;
  52         enum ndr_err_code ndr_err;
  53         struct schannel_bind bind_schannel;
  54         struct schannel_bind_ack bind_schannel_ack;
  55         struct creds_CredentialState *creds;
  56
  57         const char *workstation;
  58         const char *domain;
  59         *out = data_blob(NULL, 0);
  60
  61         switch (gensec_security->gensec_role) {
  62         case GENSEC_CLIENT:
  63                 if (state->state != SCHANNEL_STATE_START) {
  64                         /* we could parse the bind ack, but we don't know what it is yet */
  65                         return NT_STATUS_OK;
  66                 }
  67
  68                 state->creds = talloc_reference(state, cli_credentials_get_netlogon_creds(gensec_security->credentials));
  69
  70                 bind_schannel.unknown1 = 0;
  71 #if 0
  72                 /* to support this we'd need to have access to the full domain name */
  73                 bind_schannel.bind_type = 23;
  74                 bind_schannel.u.info23.domain = cli_credentials_get_domain(gensec_security->credentials);
  75                 bind_schannel.u.info23.workstation = cli_credentials_get_workstation(gensec_security->credentials);
  76                 bind_schannel.u.info23.dnsdomain = cli_credentials_get_realm(gensec_security->credentials);
  77                 /* w2k3 refuses us if we use the full DNS workstation?
  78                  why? perhaps because we don't fill in the dNSHostName
  79                  attribute in the machine account? */
  80                 bind_schannel.u.info23.dnsworkstation = cli_credentials_get_workstation(gensec_security->credentials);
  81 #else
  82                 bind_schannel.bind_type = 3;
  83                 bind_schannel.u.info3.domain = cli_credentials_get_domain(gensec_security->credentials);
  84                 bind_schannel.u.info3.workstation = cli_credentials_get_workstation(gensec_security->credentials);
  85 #endif
  86
  87                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx,
  88                                                lp_iconv_convenience(gensec_security->lp_ctx), &bind_schannel,
  89                                                (ndr_push_flags_fn_t)ndr_push_schannel_bind);
  90                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  91                         status = ndr_map_error2ntstatus(ndr_err);
  92                         DEBUG(3, ("Could not create schannel bind: %s\n",
  93                                   nt_errstr(status)));
  94                         return status;
  95                 }
  96
  97                 state->state = SCHANNEL_STATE_UPDATE_1;
  98
  99                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 100         case GENSEC_SERVER:
 101
 102                 if (state->state != SCHANNEL_STATE_START) {
 103                         /* no third leg on this protocol */
 104                         return NT_STATUS_INVALID_PARAMETER;
 105                 }
 106
 107                 /* parse the schannel startup blob */
 108                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx,
 109                         lp_iconv_convenience(gensec_security->lp_ctx),
 110                         &bind_schannel,
 111                         (ndr_pull_flags_fn_t)ndr_pull_schannel_bind);
 112                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 113                         status = ndr_map_error2ntstatus(ndr_err);
 114                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 115                                   nt_errstr(status)));
 116                         return status;
 117                 }
 118
 119                 if (bind_schannel.bind_type == 23) {
 120                         workstation = bind_schannel.u.info23.workstation;
 121                         domain = bind_schannel.u.info23.domain;
 122                 } else {
 123                         workstation = bind_schannel.u.info3.workstation;
 124                         domain = bind_schannel.u.info3.domain;
 125                 }
 126
 127                 /* pull the session key for this client */
 128                 status = schannel_fetch_session_key(out_mem_ctx, gensec_security->lp_ctx, workstation,
 129                                                     domain, &creds);
 130                 if (!NT_STATUS_IS_OK(status)) {
 131                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 132                                   workstation, nt_errstr(status)));
 133                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 134                                 return NT_STATUS_LOGON_FAILURE;
 135                         }
 136                         return status;
 137                 }
 138
 139                 state->creds = talloc_reference(state, creds);
 140
 141                 bind_schannel_ack.unknown1 = 1;
 142                 bind_schannel_ack.unknown2 = 0;
 143                 bind_schannel_ack.unknown3 = 0x6c0000;
 144
 145                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx,
 146                                                lp_iconv_convenience(gensec_security->lp_ctx), &bind_schannel_ack,
 147                                                (ndr_push_flags_fn_t)ndr_push_schannel_bind_ack);
 148                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 149                         status = ndr_map_error2ntstatus(ndr_err);
 150                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 151                                   workstation, nt_errstr(status)));
 152                         return status;
 153                 }
 154
 155                 state->state = SCHANNEL_STATE_UPDATE_1;
 156
 157                 return NT_STATUS_OK;
 158         }
 159         return NT_STATUS_INVALID_PARAMETER;
 160 }
 161
 162 /**
 163  * Return the struct creds_CredentialState.
 164  *
 165  * Make sure not to call this unless gensec is using schannel...
 166  */
 167
 168 /* TODO: make this non-public */
 169 _PUBLIC_ NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
 170                                TALLOC_CTX *mem_ctx,
 171                                struct creds_CredentialState **creds)
 172 {
 173         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 174
 175         *creds = talloc_reference(mem_ctx, state->creds);
 176         if (!*creds) {
 177                 return NT_STATUS_NO_MEMORY;
 178         }
 179         return NT_STATUS_OK;
 180 }
 181
 182
 183 /**
 184  * Returns anonymous credentials for schannel, matching Win2k3.
 185  *
 186  */
 187
 188 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 189                                          struct auth_session_info **_session_info)
 190 {
 191         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 192         return auth_anonymous_session_info(state, gensec_security->lp_ctx, _session_info);
 193 }
 194
 195 static NTSTATUS schannel_start(struct gensec_security *gensec_security)
 196 {
 197         struct schannel_state *state;
 198
 199         state = talloc(gensec_security, struct schannel_state);
 200         if (!state) {
 201                 return NT_STATUS_NO_MEMORY;
 202         }
 203
 204         state->state = SCHANNEL_STATE_START;
 205         state->seq_num = 0;
 206         gensec_security->private_data = state;
 207
 208         return NT_STATUS_OK;
 209 }
 210
 211 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 212 {
 213         NTSTATUS status;
 214         struct schannel_state *state;
 215
 216         status = schannel_start(gensec_security);
 217         if (!NT_STATUS_IS_OK(status)) {
 218                 return status;
 219         }
 220
 221         state = (struct schannel_state *)gensec_security->private_data;
 222         state->initiator = false;
 223
 224         return NT_STATUS_OK;
 225 }
 226
 227 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 228 {
 229         NTSTATUS status;
 230         struct schannel_state *state;
 231
 232         status = schannel_start(gensec_security);
 233         if (!NT_STATUS_IS_OK(status)) {
 234                 return status;
 235         }
 236
 237         state = (struct schannel_state *)gensec_security->private_data;
 238         state->initiator = true;
 239
 240         return NT_STATUS_OK;
 241 }
 242
 243
 244 static bool schannel_have_feature(struct gensec_security *gensec_security,
 245                                          uint32_t feature)
 246 {
 247         if (feature & (GENSEC_FEATURE_SIGN |
 248                        GENSEC_FEATURE_SEAL)) {
 249                 return true;
 250         }
 251         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 252                 return true;
 253         }
 254         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
 255                 return true;
 256         }
 257         return false;
 258 }
 259
 260
 261 static const struct gensec_security_ops gensec_schannel_security_ops = {
 262         .name           = "schannel",
 263         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 264         .client_start   = schannel_client_start,
 265         .server_start   = schannel_server_start,
 266         .update         = schannel_update,
 267         .seal_packet    = schannel_seal_packet,
 268         .sign_packet    = schannel_sign_packet,
 269         .check_packet   = schannel_check_packet,
 270         .unseal_packet  = schannel_unseal_packet,
 271         .session_key    = schannel_session_key,
 272         .session_info   = schannel_session_info,
 273         .sig_size       = schannel_sig_size,
 274         .have_feature   = schannel_have_feature,
 275         .enabled        = true,
 276         .priority       = GENSEC_SCHANNEL
 277 };
 278
 279 _PUBLIC_ NTSTATUS gensec_schannel_init(void)
 280 {
 281         NTSTATUS ret;
 282         ret = gensec_register(&gensec_schannel_security_ops);
 283         if (!NT_STATUS_IS_OK(ret)) {
 284                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 285                         gensec_schannel_security_ops.name));
 286                 return ret;
 287         }
 288
 289         return ret;
 290 }