source4/winbind/wb_pam_auth.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Authenticate a user
   5
   6    Copyright (C) Volker Lendecke 2005
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 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 2 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, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24 #include "includes.h"
  25 #include "libcli/composite/composite.h"
  26 #include "winbind/wb_server.h"
  27 #include "smbd/service_task.h"
  28 #include "libcli/auth/credentials.h"
  29 #include "libcli/auth/proto.h"
  30
  31 /* Oh, there is so much to keep an eye on when authenticating a user.  Oh my! */
  32 struct pam_auth_crap_state {
  33         struct composite_context *ctx;
  34         struct event_context *event_ctx;
  35         uint32_t logon_parameters;
  36         const char *domain_name;
  37         const char *user_name;
  38         const char *workstation;
  39         DATA_BLOB chal, nt_resp, lm_resp;
  40
  41         struct creds_CredentialState *creds_state;
  42         struct netr_Authenticator auth, auth2;
  43         struct netr_NetworkInfo ninfo;
  44         struct netr_LogonSamLogon r;
  45
  46         struct netr_UserSessionKey user_session_key;
  47         struct netr_LMSessionKey lm_key;
  48         DATA_BLOB info3;
  49 };
  50
  51 /*
  52  * NTLM authentication.
  53 */
  54
  55 static void pam_auth_crap_recv_domain(struct composite_context *ctx);
  56 static void pam_auth_crap_recv_samlogon(struct rpc_request *req);
  57
  58 struct composite_context *wb_cmd_pam_auth_crap_send(TALLOC_CTX *mem_ctx,
  59                                                     struct wbsrv_service *service,
  60                                                     uint32_t logon_parameters,
  61                                                     const char *domain,
  62                                                     const char *user,
  63                                                     const char *workstation,
  64                                                     DATA_BLOB chal,
  65                                                     DATA_BLOB nt_resp,
  66                                                     DATA_BLOB lm_resp)
  67 {
  68         struct composite_context *result, *ctx;
  69         struct pam_auth_crap_state *state;
  70
  71         result = talloc(mem_ctx, struct composite_context);
  72         if (result == NULL) goto failed;
  73         result->state = COMPOSITE_STATE_IN_PROGRESS;
  74         result->async.fn = NULL;
  75         result->event_ctx = service->task->event_ctx;
  76
  77         state = talloc(result, struct pam_auth_crap_state);
  78         if (state == NULL) goto failed;
  79         state->ctx = result;
  80         result->private_data = state;
  81
  82         state->logon_parameters = logon_parameters;
  83
  84         state->domain_name = talloc_strdup(state, domain);
  85         if (state->domain_name == NULL) goto failed;
  86
  87         state->user_name = talloc_strdup(state, user);
  88         if (state->user_name == NULL) goto failed;
  89
  90         state->workstation = talloc_strdup(state, workstation);
  91         if (state->workstation == NULL) goto failed;
  92
  93         state->chal = data_blob_talloc(state, chal.data, chal.length);
  94         if ((chal.data != NULL) && (state->chal.data == NULL)) goto failed;
  95
  96         state->nt_resp = data_blob_talloc(state, nt_resp.data, nt_resp.length);
  97         if ((nt_resp.data != NULL) &&
  98             (state->nt_resp.data == NULL)) goto failed;
  99
 100         state->lm_resp = data_blob_talloc(state, lm_resp.data, lm_resp.length);
 101         if ((lm_resp.data != NULL) &&
 102             (state->lm_resp.data == NULL)) goto failed;
 103
 104         ctx = wb_sid2domain_send(state, service, service->primary_sid);
 105         if (ctx == NULL) goto failed;
 106
 107         ctx->async.fn = pam_auth_crap_recv_domain;
 108         ctx->async.private_data = state;
 109         return result;
 110
 111  failed:
 112         talloc_free(result);
 113         return NULL;
 114 }
 115
 116 /*
 117     NTLM Authentication
 118
 119     Send of a SamLogon request to authenticate a user.
 120 */
 121 static void pam_auth_crap_recv_domain(struct composite_context *ctx)
 122 {
 123         struct pam_auth_crap_state *state =
 124                 talloc_get_type(ctx->async.private_data,
 125                                 struct pam_auth_crap_state);
 126         struct rpc_request *req;
 127         struct wbsrv_domain *domain;
 128
 129         state->ctx->status = wb_sid2domain_recv(ctx, &domain);
 130         state->creds_state =
 131                 cli_credentials_get_netlogon_creds(domain->schannel_creds);
 132
 133         creds_client_authenticator(state->creds_state, &state->auth);
 134
 135         state->ninfo.identity_info.account_name.string = state->user_name;
 136         state->ninfo.identity_info.domain_name.string =  state->domain_name;
 137         state->ninfo.identity_info.parameter_control = state->logon_parameters;
 138         state->ninfo.identity_info.logon_id_low = 0;
 139         state->ninfo.identity_info.logon_id_high = 0;
 140         state->ninfo.identity_info.workstation.string = state->workstation;
 141
 142         SMB_ASSERT(state->chal.length == sizeof(state->ninfo.challenge));
 143         memcpy(state->ninfo.challenge, state->chal.data,
 144                sizeof(state->ninfo.challenge));
 145
 146         state->ninfo.nt.length = state->nt_resp.length;
 147         state->ninfo.nt.data = state->nt_resp.data;
 148         state->ninfo.lm.length = state->lm_resp.length;
 149         state->ninfo.lm.data = state->lm_resp.data;
 150
 151         state->r.in.server_name = talloc_asprintf(
 152                 state, "\\\\%s", dcerpc_server_name(domain->netlogon_pipe));
 153         if (composite_nomem(state->r.in.server_name, state->ctx)) return;
 154
 155         ZERO_STRUCT(state->auth2);
 156
 157         state->r.in.computer_name =
 158                 cli_credentials_get_workstation(domain->schannel_creds);
 159         state->r.in.credential = &state->auth;
 160         state->r.in.return_authenticator = &state->auth2;
 161         state->r.in.logon_level = 2;
 162         state->r.in.validation_level = 3;
 163         state->r.in.logon.network = &state->ninfo;
 164         state->r.out.return_authenticator = NULL;
 165
 166         req = dcerpc_netr_LogonSamLogon_send(domain->netlogon_pipe, state,
 167                                              &state->r);
 168         composite_continue_rpc(state->ctx, req, pam_auth_crap_recv_samlogon,
 169                                state);
 170 }
 171
 172 /*
 173    NTLM Authentication
 174
 175    Check the SamLogon reply, decrypt and parse out the session keys and the
 176    info3 structure.
 177 */
 178 static void pam_auth_crap_recv_samlogon(struct rpc_request *req)
 179 {
 180         struct pam_auth_crap_state *state =
 181                 talloc_get_type(req->async.private,
 182                                 struct pam_auth_crap_state);
 183         struct netr_SamBaseInfo *base;
 184         DATA_BLOB tmp_blob;
 185
 186         state->ctx->status = dcerpc_ndr_request_recv(req);
 187         if (!composite_is_ok(state->ctx)) return;
 188
 189         if ((state->r.out.return_authenticator == NULL) ||
 190             (!creds_client_check(state->creds_state,
 191                                  &state->r.out.return_authenticator->cred))) {
 192                 DEBUG(0, ("Credentials check failed!\n"));
 193                 composite_error(state->ctx, NT_STATUS_ACCESS_DENIED);
 194                 return;
 195         }
 196
 197         state->ctx->status = state->r.out.result;
 198         if (!composite_is_ok(state->ctx)) return;
 199
 200         /* Decrypt the session keys before we reform the info3, so the
 201          * person on the other end of winbindd pipe doesn't have to.
 202          * They won't have the encryption key anyway */
 203         creds_decrypt_samlogon(state->creds_state,
 204                                state->r.in.validation_level,
 205                                &state->r.out.validation);
 206
 207         state->ctx->status = ndr_push_struct_blob(
 208                 &tmp_blob, state, state->r.out.validation.sam3,
 209                 (ndr_push_flags_fn_t)ndr_push_netr_SamInfo3);
 210         if (!composite_is_ok(state->ctx)) return;
 211
 212         /* The Samba3 protocol is a bit broken (due to non-IDL
 213          * heritage, so for compatability we must add a non-zero 4
 214          * bytes to the info3 */
 215         state->info3 = data_blob_talloc(state, NULL, tmp_blob.length+4);
 216         if (composite_nomem(state->info3.data, state->ctx)) return;
 217
 218         SIVAL(state->info3.data, 0, 1);
 219         memcpy(state->info3.data+4, tmp_blob.data, tmp_blob.length);
 220
 221         /* We actually only ask for level 3, and assume it above, but
 222          * anyway... */
 223
 224         base = NULL;
 225         switch(state->r.in.validation_level) {
 226         case 2:
 227                 base = &state->r.out.validation.sam2->base;
 228                 break;
 229         case 3:
 230                 base = &state->r.out.validation.sam3->base;
 231                 break;
 232         case 6:
 233                 base = &state->r.out.validation.sam6->base;
 234                 break;
 235         }
 236         if (base == NULL) {
 237                 composite_error(state->ctx, NT_STATUS_INTERNAL_ERROR);
 238                 return;
 239         }
 240
 241         state->user_session_key = base->key;
 242         state->lm_key = base->LMSessKey;
 243
 244         /* Give the caller the most accurate username possible.
 245          * Assists where case sensitive comparisons may be done by our
 246          * ntlm_auth callers */
 247         if (base->account_name.string) {
 248                 state->user_name = base->account_name.string;
 249                 talloc_steal(state, base->account_name.string);
 250         }
 251         if (base->domain.string) {
 252                 state->domain_name = base->domain.string;
 253                 talloc_steal(state, base->domain.string);
 254         }
 255
 256         composite_done(state->ctx);
 257 }
 258
 259 NTSTATUS wb_cmd_pam_auth_crap_recv(struct composite_context *c,
 260                                    TALLOC_CTX *mem_ctx,
 261                                    DATA_BLOB *info3,
 262                                    struct netr_UserSessionKey *user_session_key,
 263                                    struct netr_LMSessionKey *lm_key,
 264                                    char **unix_username)
 265 {
 266         struct pam_auth_crap_state *state =
 267                 talloc_get_type(c->private_data, struct pam_auth_crap_state);
 268         NTSTATUS status = composite_wait(c);
 269         if (NT_STATUS_IS_OK(status)) {
 270                 info3->length = state->info3.length;
 271                 info3->data = talloc_steal(mem_ctx, state->info3.data);
 272                 *user_session_key = state->user_session_key;
 273                 *lm_key = state->lm_key;
 274                 *unix_username = talloc_asprintf(mem_ctx, "%s%s%s",
 275                                                  state->domain_name,
 276                                                  lp_winbind_separator(),
 277                                                  state->user_name);
 278                 if (!*unix_username) {
 279                         status = NT_STATUS_NO_MEMORY;
 280                 }
 281         }
 282         talloc_free(state);
 283         return status;
 284 }
 285
 286 NTSTATUS wb_cmd_pam_auth_crap(TALLOC_CTX *mem_ctx,
 287                               struct wbsrv_service *service,
 288                               uint32_t logon_parameters,
 289                               const char *domain, const char *user,
 290                               const char *workstation,
 291                               DATA_BLOB chal, DATA_BLOB nt_resp,
 292                               DATA_BLOB lm_resp,
 293                               DATA_BLOB *info3,
 294                               struct netr_UserSessionKey *user_session_key,
 295                               struct netr_LMSessionKey *lm_key,
 296                               char **unix_username)
 297 {
 298         struct composite_context *c =
 299                 wb_cmd_pam_auth_crap_send(mem_ctx, service, logon_parameters,
 300                                           domain, user, workstation,
 301                                           chal, nt_resp, lm_resp);
 302         return wb_cmd_pam_auth_crap_recv(c, mem_ctx, info3, user_session_key,
 303                                          lm_key, unix_username);
 304 }
 305
 306 struct composite_context *wb_cmd_pam_auth_send(TALLOC_CTX *mem_ctx,
 307                                                struct wbsrv_service *service,
 308                                                const char *domain,
 309                                                const char *user,
 310                                                const char *password)
 311 {
 312         struct cli_credentials *credentials;
 313         const char *workstation;
 314         NTSTATUS status;
 315
 316         DATA_BLOB chal, nt_resp, lm_resp, names_blob;
 317         int flags = CLI_CRED_NTLM_AUTH;
 318         if (lp_client_lanman_auth()) {
 319                 flags |= CLI_CRED_LANMAN_AUTH;
 320         }
 321
 322         if (lp_client_ntlmv2_auth()) {
 323                 flags |= CLI_CRED_NTLMv2_AUTH;
 324         }
 325
 326         DEBUG(5, ("wbsrv_samba3_pam_auth called\n"));
 327
 328         credentials = cli_credentials_init(mem_ctx);
 329         if (!credentials) {
 330                 return NULL;
 331         }
 332         cli_credentials_set_conf(credentials);
 333         cli_credentials_set_domain(credentials, domain, CRED_SPECIFIED);
 334         cli_credentials_set_username(credentials, user, CRED_SPECIFIED);
 335
 336         cli_credentials_set_password(credentials, password, CRED_SPECIFIED);
 337
 338         chal = data_blob_talloc(mem_ctx, NULL, 8);
 339         if (!chal.data) {
 340                 return NULL;
 341         }
 342         generate_random_buffer(chal.data, chal.length);
 343         cli_credentials_get_ntlm_username_domain(credentials, mem_ctx,
 344                                                  &user, &domain);
 345         /* for best compatability with multiple vitual netbios names
 346          * on the host, this should be generated from the
 347          * cli_credentials associated with the machine account */
 348         workstation = cli_credentials_get_workstation(credentials);
 349
 350         names_blob = NTLMv2_generate_names_blob(
 351                 mem_ctx,
 352                 cli_credentials_get_workstation(credentials),
 353                 cli_credentials_get_domain(credentials));
 354
 355         status = cli_credentials_get_ntlm_response(
 356                 credentials, mem_ctx, &flags, chal, names_blob,
 357                 &lm_resp, &nt_resp, NULL, NULL);
 358         if (!NT_STATUS_IS_OK(status)) {
 359                 return NULL;
 360         }
 361         return wb_cmd_pam_auth_crap_send(mem_ctx, service,
 362                                          0 /* logon parameters */,
 363                                          domain, user, workstation,
 364                                          chal, nt_resp, lm_resp);
 365 }
 366
 367 NTSTATUS wb_cmd_pam_auth_recv(struct composite_context *c)
 368 {
 369         struct pam_auth_crap_state *state =
 370                 talloc_get_type(c->private_data, struct pam_auth_crap_state);
 371         NTSTATUS status = composite_wait(c);
 372         talloc_free(state);
 373         return status;
 374 }
 375
 376 NTSTATUS wb_cmd_pam_auth(TALLOC_CTX *mem_ctx, struct wbsrv_service *service,
 377                          const char *domain, const char *user,
 378                          const char *password)
 379 {
 380         struct composite_context *c =
 381                 wb_cmd_pam_auth_send(mem_ctx, service, domain, user, password);
 382         return wb_cmd_pam_auth_recv(c);
 383 }