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