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