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, &bind_schannel,
  86                                                (ndr_push_flags_fn_t)ndr_push_schannel_bind);
  87                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
  88                         status = ndr_map_error2ntstatus(ndr_err);
  89                         DEBUG(3, ("Could not create schannel bind: %s\n",
  90                                   nt_errstr(status)));
  91                         return status;
  92                 }
  93
  94                 state->state = SCHANNEL_STATE_UPDATE_1;
  95
  96                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
  97         case GENSEC_SERVER:
  98
  99                 if (state->state != SCHANNEL_STATE_START) {
 100                         /* no third leg on this protocol */
 101                         return NT_STATUS_INVALID_PARAMETER;
 102                 }
 103
 104                 /* parse the schannel startup blob */
 105                 ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel,
 106                                                (ndr_pull_flags_fn_t)ndr_pull_schannel_bind);
 107                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 108                         status = ndr_map_error2ntstatus(ndr_err);
 109                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 110                                   nt_errstr(status)));
 111                         return status;
 112                 }
 113
 114                 if (bind_schannel.bind_type == 23) {
 115                         workstation = bind_schannel.u.info23.workstation;
 116                         domain = bind_schannel.u.info23.domain;
 117                 } else {
 118                         workstation = bind_schannel.u.info3.workstation;
 119                         domain = bind_schannel.u.info3.domain;
 120                 }
 121
 122                 /* pull the session key for this client */
 123                 status = schannel_fetch_session_key(out_mem_ctx, gensec_security->lp_ctx, workstation,
 124                                                     domain, &creds);
 125                 if (!NT_STATUS_IS_OK(status)) {
 126                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 127                                   workstation, nt_errstr(status)));
 128                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 129                                 return NT_STATUS_LOGON_FAILURE;
 130                         }
 131                         return status;
 132                 }
 133
 134                 state->creds = talloc_reference(state, creds);
 135
 136                 bind_schannel_ack.unknown1 = 1;
 137                 bind_schannel_ack.unknown2 = 0;
 138                 bind_schannel_ack.unknown3 = 0x6c0000;
 139
 140                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack,
 141                                                (ndr_push_flags_fn_t)ndr_push_schannel_bind_ack);
 142                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 143                         status = ndr_map_error2ntstatus(ndr_err);
 144                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 145                                   workstation, nt_errstr(status)));
 146                         return status;
 147                 }
 148
 149                 state->state = SCHANNEL_STATE_UPDATE_1;
 150
 151                 return NT_STATUS_OK;
 152         }
 153         return NT_STATUS_INVALID_PARAMETER;
 154 }
 155
 156 /**
 157  * Return the struct creds_CredentialState.
 158  *
 159  * Make sure not to call this unless gensec is using schannel...
 160  */
 161
 162 /* TODO: make this non-public */
 163 _PUBLIC_ NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
 164                                TALLOC_CTX *mem_ctx,
 165                                struct creds_CredentialState **creds)
 166 {
 167         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 168
 169         *creds = talloc_reference(mem_ctx, state->creds);
 170         if (!*creds) {
 171                 return NT_STATUS_NO_MEMORY;
 172         }
 173         return NT_STATUS_OK;
 174 }
 175
 176
 177 /**
 178  * Returns anonymous credentials for schannel, matching Win2k3.
 179  *
 180  */
 181
 182 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 183                                          struct auth_session_info **_session_info)
 184 {
 185         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 186         return auth_anonymous_session_info(state, gensec_security->lp_ctx, _session_info);
 187 }
 188
 189 static NTSTATUS schannel_start(struct gensec_security *gensec_security)
 190 {
 191         struct schannel_state *state;
 192
 193         state = talloc(gensec_security, struct schannel_state);
 194         if (!state) {
 195                 return NT_STATUS_NO_MEMORY;
 196         }
 197
 198         state->state = SCHANNEL_STATE_START;
 199         state->seq_num = 0;
 200         gensec_security->private_data = state;
 201
 202         return NT_STATUS_OK;
 203 }
 204
 205 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 206 {
 207         NTSTATUS status;
 208         struct schannel_state *state;
 209
 210         status = schannel_start(gensec_security);
 211         if (!NT_STATUS_IS_OK(status)) {
 212                 return status;
 213         }
 214
 215         state = (struct schannel_state *)gensec_security->private_data;
 216         state->initiator = false;
 217
 218         return NT_STATUS_OK;
 219 }
 220
 221 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 222 {
 223         NTSTATUS status;
 224         struct schannel_state *state;
 225
 226         status = schannel_start(gensec_security);
 227         if (!NT_STATUS_IS_OK(status)) {
 228                 return status;
 229         }
 230
 231         state = (struct schannel_state *)gensec_security->private_data;
 232         state->initiator = true;
 233
 234         return NT_STATUS_OK;
 235 }
 236
 237
 238 static bool schannel_have_feature(struct gensec_security *gensec_security,
 239                                          uint32_t feature)
 240 {
 241         if (feature & (GENSEC_FEATURE_SIGN |
 242                        GENSEC_FEATURE_SEAL)) {
 243                 return true;
 244         }
 245         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 246                 return true;
 247         }
 248         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
 249                 return true;
 250         }
 251         return false;
 252 }
 253
 254
 255 static const struct gensec_security_ops gensec_schannel_security_ops = {
 256         .name           = "schannel",
 257         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 258         .client_start   = schannel_client_start,
 259         .server_start   = schannel_server_start,
 260         .update         = schannel_update,
 261         .seal_packet    = schannel_seal_packet,
 262         .sign_packet    = schannel_sign_packet,
 263         .check_packet   = schannel_check_packet,
 264         .unseal_packet  = schannel_unseal_packet,
 265         .session_key    = schannel_session_key,
 266         .session_info   = schannel_session_info,
 267         .sig_size       = schannel_sig_size,
 268         .have_feature   = schannel_have_feature,
 269         .enabled        = true,
 270         .priority       = GENSEC_SCHANNEL
 271 };
 272
 273 NTSTATUS gensec_schannel_init(void)
 274 {
 275         NTSTATUS ret;
 276         ret = gensec_register(&gensec_schannel_security_ops);
 277         if (!NT_STATUS_IS_OK(ret)) {
 278                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 279                         gensec_schannel_security_ops.name));
 280                 return ret;
 281         }
 282
 283         return ret;
 284 }