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, &bind_schannel,
 107                                                (ndr_pull_flags_fn_t)ndr_pull_schannel_bind);
 108                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 109                         status = ndr_map_error2ntstatus(ndr_err);
 110                         DEBUG(3, ("Could not parse incoming schannel bind: %s\n",
 111                                   nt_errstr(status)));
 112                         return status;
 113                 }
 114
 115                 if (bind_schannel.bind_type == 23) {
 116                         workstation = bind_schannel.u.info23.workstation;
 117                         domain = bind_schannel.u.info23.domain;
 118                 } else {
 119                         workstation = bind_schannel.u.info3.workstation;
 120                         domain = bind_schannel.u.info3.domain;
 121                 }
 122
 123                 /* pull the session key for this client */
 124                 status = schannel_fetch_session_key(out_mem_ctx, gensec_security->lp_ctx, workstation,
 125                                                     domain, &creds);
 126                 if (!NT_STATUS_IS_OK(status)) {
 127                         DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n",
 128                                   workstation, nt_errstr(status)));
 129                         if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
 130                                 return NT_STATUS_LOGON_FAILURE;
 131                         }
 132                         return status;
 133                 }
 134
 135                 state->creds = talloc_reference(state, creds);
 136
 137                 bind_schannel_ack.unknown1 = 1;
 138                 bind_schannel_ack.unknown2 = 0;
 139                 bind_schannel_ack.unknown3 = 0x6c0000;
 140
 141                 ndr_err = ndr_push_struct_blob(out, out_mem_ctx,
 142                                                lp_iconv_convenience(gensec_security->lp_ctx), &bind_schannel_ack,
 143                                                (ndr_push_flags_fn_t)ndr_push_schannel_bind_ack);
 144                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 145                         status = ndr_map_error2ntstatus(ndr_err);
 146                         DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n",
 147                                   workstation, nt_errstr(status)));
 148                         return status;
 149                 }
 150
 151                 state->state = SCHANNEL_STATE_UPDATE_1;
 152
 153                 return NT_STATUS_OK;
 154         }
 155         return NT_STATUS_INVALID_PARAMETER;
 156 }
 157
 158 /**
 159  * Return the struct creds_CredentialState.
 160  *
 161  * Make sure not to call this unless gensec is using schannel...
 162  */
 163
 164 /* TODO: make this non-public */
 165 _PUBLIC_ NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
 166                                TALLOC_CTX *mem_ctx,
 167                                struct creds_CredentialState **creds)
 168 {
 169         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 170
 171         *creds = talloc_reference(mem_ctx, state->creds);
 172         if (!*creds) {
 173                 return NT_STATUS_NO_MEMORY;
 174         }
 175         return NT_STATUS_OK;
 176 }
 177
 178
 179 /**
 180  * Returns anonymous credentials for schannel, matching Win2k3.
 181  *
 182  */
 183
 184 static NTSTATUS schannel_session_info(struct gensec_security *gensec_security,
 185                                          struct auth_session_info **_session_info)
 186 {
 187         struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state);
 188         return auth_anonymous_session_info(state, gensec_security->lp_ctx, _session_info);
 189 }
 190
 191 static NTSTATUS schannel_start(struct gensec_security *gensec_security)
 192 {
 193         struct schannel_state *state;
 194
 195         state = talloc(gensec_security, struct schannel_state);
 196         if (!state) {
 197                 return NT_STATUS_NO_MEMORY;
 198         }
 199
 200         state->state = SCHANNEL_STATE_START;
 201         state->seq_num = 0;
 202         gensec_security->private_data = state;
 203
 204         return NT_STATUS_OK;
 205 }
 206
 207 static NTSTATUS schannel_server_start(struct gensec_security *gensec_security)
 208 {
 209         NTSTATUS status;
 210         struct schannel_state *state;
 211
 212         status = schannel_start(gensec_security);
 213         if (!NT_STATUS_IS_OK(status)) {
 214                 return status;
 215         }
 216
 217         state = (struct schannel_state *)gensec_security->private_data;
 218         state->initiator = false;
 219
 220         return NT_STATUS_OK;
 221 }
 222
 223 static NTSTATUS schannel_client_start(struct gensec_security *gensec_security)
 224 {
 225         NTSTATUS status;
 226         struct schannel_state *state;
 227
 228         status = schannel_start(gensec_security);
 229         if (!NT_STATUS_IS_OK(status)) {
 230                 return status;
 231         }
 232
 233         state = (struct schannel_state *)gensec_security->private_data;
 234         state->initiator = true;
 235
 236         return NT_STATUS_OK;
 237 }
 238
 239
 240 static bool schannel_have_feature(struct gensec_security *gensec_security,
 241                                          uint32_t feature)
 242 {
 243         if (feature & (GENSEC_FEATURE_SIGN |
 244                        GENSEC_FEATURE_SEAL)) {
 245                 return true;
 246         }
 247         if (feature & GENSEC_FEATURE_DCE_STYLE) {
 248                 return true;
 249         }
 250         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
 251                 return true;
 252         }
 253         return false;
 254 }
 255
 256
 257 static const struct gensec_security_ops gensec_schannel_security_ops = {
 258         .name           = "schannel",
 259         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
 260         .client_start   = schannel_client_start,
 261         .server_start   = schannel_server_start,
 262         .update         = schannel_update,
 263         .seal_packet    = schannel_seal_packet,
 264         .sign_packet    = schannel_sign_packet,
 265         .check_packet   = schannel_check_packet,
 266         .unseal_packet  = schannel_unseal_packet,
 267         .session_key    = schannel_session_key,
 268         .session_info   = schannel_session_info,
 269         .sig_size       = schannel_sig_size,
 270         .have_feature   = schannel_have_feature,
 271         .enabled        = true,
 272         .priority       = GENSEC_SCHANNEL
 273 };
 274
 275 NTSTATUS gensec_schannel_init(void)
 276 {
 277         NTSTATUS ret;
 278         ret = gensec_register(&gensec_schannel_security_ops);
 279         if (!NT_STATUS_IS_OK(ret)) {
 280                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 281                         gensec_schannel_security_ops.name));
 282                 return ret;
 283         }
 284
 285         return ret;
 286 }