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 "auth/credentials/credentials.h"
  29 #include "libcli/auth/libcli_auth.h"
  30 #include "librpc/gen_ndr/ndr_netlogon.h"
  31 #include "librpc/gen_ndr/ndr_netlogon_c.h"
  32
  33 /* Oh, there is so much to keep an eye on when authenticating a user.  Oh my! */
  34 struct pam_auth_crap_state {
  35         struct composite_context *ctx;
  36         struct event_context *event_ctx;
  37         uint32_t logon_parameters;
  38         const char *domain_name;
  39         const char *user_name;
  40         char *unix_username;
  41         const char *workstation;
  42         DATA_BLOB chal, nt_resp, lm_resp;
  43
  44         struct creds_CredentialState *creds_state;
  45         struct netr_Authenticator auth, auth2;
  46         struct netr_NetworkInfo ninfo;
  47         struct netr_LogonSamLogon r;
  48
  49         struct netr_UserSessionKey user_session_key;
  50         struct netr_LMSessionKey lm_key;
  51         DATA_BLOB info3;
  52 };
  53
  54 /*
  55  * NTLM authentication.
  56 */
  57
  58 static void pam_auth_crap_recv_domain(struct composite_context *ctx);
  59 static void pam_auth_crap_recv_samlogon(struct rpc_request *req);
  60
  61 struct composite_context *wb_cmd_pam_auth_crap_send(TALLOC_CTX *mem_ctx,
  62                                                     struct wbsrv_service *service,
  63                                                     uint32_t logon_parameters,
  64                                                     const char *domain,
  65                                                     const char *user,
  66                                                     const char *workstation,
  67                                                     DATA_BLOB chal,
  68                                                     DATA_BLOB nt_resp,
  69                                                     DATA_BLOB lm_resp)
  70 {
  71         struct composite_context *result, *ctx;
  72         struct pam_auth_crap_state *state;
  73
  74         result = talloc(mem_ctx, struct composite_context);
  75         if (result == NULL) goto failed;
  76         result->state = COMPOSITE_STATE_IN_PROGRESS;
  77         result->async.fn = NULL;
  78         result->event_ctx = service->task->event_ctx;
  79
  80         state = talloc(result, struct pam_auth_crap_state);
  81         if (state == NULL) goto failed;
  82         state->ctx = result;
  83         result->private_data = state;
  84
  85         state->logon_parameters = logon_parameters;
  86
  87         state->domain_name = talloc_strdup(state, domain);
  88         if (state->domain_name == NULL) goto failed;
  89
  90         state->user_name = talloc_strdup(state, user);
  91         if (state->user_name == NULL) goto failed;
  92
  93         state->unix_username = NULL;
  94
  95         state->workstation = talloc_strdup(state, workstation);
  96         if (state->workstation == NULL) goto failed;
  97
  98         state->chal = data_blob_talloc(state, chal.data, chal.length);
  99         if ((chal.data != NULL) && (state->chal.data == NULL)) goto failed;
 100
 101         state->nt_resp = data_blob_talloc(state, nt_resp.data, nt_resp.length);
 102         if ((nt_resp.data != NULL) &&
 103             (state->nt_resp.data == NULL)) goto failed;
 104
 105         state->lm_resp = data_blob_talloc(state, lm_resp.data, lm_resp.length);
 106         if ((lm_resp.data != NULL) &&
 107             (state->lm_resp.data == NULL)) goto failed;
 108
 109         ctx = wb_sid2domain_send(state, service, service->primary_sid);
 110         if (ctx == NULL) goto failed;
 111
 112         ctx->async.fn = pam_auth_crap_recv_domain;
 113         ctx->async.private_data = state;
 114         return result;
 115
 116  failed:
 117         talloc_free(result);
 118         return NULL;
 119 }
 120
 121 /*
 122     NTLM Authentication
 123
 124     Send of a SamLogon request to authenticate a user.
 125 */
 126 static void pam_auth_crap_recv_domain(struct composite_context *ctx)
 127 {
 128         struct pam_auth_crap_state *state =
 129                 talloc_get_type(ctx->async.private_data,
 130                                 struct pam_auth_crap_state);
 131         struct rpc_request *req;
 132         struct wbsrv_domain *domain;
 133
 134         state->ctx->status = wb_sid2domain_recv(ctx, &domain);
 135         state->creds_state =
 136                 cli_credentials_get_netlogon_creds(domain->schannel_creds);
 137
 138         creds_client_authenticator(state->creds_state, &state->auth);
 139
 140         state->ninfo.identity_info.account_name.string = state->user_name;
 141         state->ninfo.identity_info.domain_name.string =  state->domain_name;
 142         state->ninfo.identity_info.parameter_control = state->logon_parameters;
 143         state->ninfo.identity_info.logon_id_low = 0;
 144         state->ninfo.identity_info.logon_id_high = 0;
 145         state->ninfo.identity_info.workstation.string = state->workstation;
 146
 147         SMB_ASSERT(state->chal.length == sizeof(state->ninfo.challenge));
 148         memcpy(state->ninfo.challenge, state->chal.data,
 149                sizeof(state->ninfo.challenge));
 150
 151         state->ninfo.nt.length = state->nt_resp.length;
 152         state->ninfo.nt.data = state->nt_resp.data;
 153         state->ninfo.lm.length = state->lm_resp.length;
 154         state->ninfo.lm.data = state->lm_resp.data;
 155
 156         state->r.in.server_name = talloc_asprintf(
 157                 state, "\\\\%s", dcerpc_server_name(domain->netlogon_pipe));
 158         if (composite_nomem(state->r.in.server_name, state->ctx)) return;
 159
 160         ZERO_STRUCT(state->auth2);
 161
 162         state->r.in.computer_name =
 163                 cli_credentials_get_workstation(domain->schannel_creds);
 164         state->r.in.credential = &state->auth;
 165         state->r.in.return_authenticator = &state->auth2;
 166         state->r.in.logon_level = 2;
 167         state->r.in.validation_level = 3;
 168         state->r.in.logon.network = &state->ninfo;
 169         state->r.out.return_authenticator = NULL;
 170
 171         req = dcerpc_netr_LogonSamLogon_send(domain->netlogon_pipe, state,
 172                                              &state->r);
 173         composite_continue_rpc(state->ctx, req, pam_auth_crap_recv_samlogon,
 174                                state);
 175 }
 176
 177 /*
 178    NTLM Authentication
 179
 180    Check the SamLogon reply, decrypt and parse out the session keys and the
 181    info3 structure.
 182 */
 183 static void pam_auth_crap_recv_samlogon(struct rpc_request *req)
 184 {
 185         struct pam_auth_crap_state *state =
 186                 talloc_get_type(req->async.private,
 187                                 struct pam_auth_crap_state);
 188         struct netr_SamBaseInfo *base;
 189         DATA_BLOB tmp_blob;
 190
 191         state->ctx->status = dcerpc_ndr_request_recv(req);
 192         if (!composite_is_ok(state->ctx)) return;
 193
 194         if ((state->r.out.return_authenticator == NULL) ||
 195             (!creds_client_check(state->creds_state,
 196                                  &state->r.out.return_authenticator->cred))) {
 197                 DEBUG(0, ("Credentials check failed!\n"));
 198                 composite_error(state->ctx, NT_STATUS_ACCESS_DENIED);
 199                 return;
 200         }
 201
 202         state->ctx->status = state->r.out.result;
 203         if (!composite_is_ok(state->ctx)) return;
 204
 205         /* Decrypt the session keys before we reform the info3, so the
 206          * person on the other end of winbindd pipe doesn't have to.
 207          * They won't have the encryption key anyway */
 208         creds_decrypt_samlogon(state->creds_state,
 209                                state->r.in.validation_level,
 210                                &state->r.out.validation);
 211
 212         state->ctx->status = ndr_push_struct_blob(
 213                 &tmp_blob, state, state->r.out.validation.sam3,
 214                 (ndr_push_flags_fn_t)ndr_push_netr_SamInfo3);
 215         if (!composite_is_ok(state->ctx)) return;
 216
 217         /* The Samba3 protocol is a bit broken (due to non-IDL
 218          * heritage, so for compatability we must add a non-zero 4
 219          * bytes to the info3 */
 220         state->info3 = data_blob_talloc(state, NULL, tmp_blob.length+4);
 221         if (composite_nomem(state->info3.data, state->ctx)) return;
 222
 223         SIVAL(state->info3.data, 0, 1);
 224         memcpy(state->info3.data+4, tmp_blob.data, tmp_blob.length);
 225
 226         /* We actually only ask for level 3, and assume it above, but
 227          * anyway... */
 228
 229         base = NULL;
 230         switch(state->r.in.validation_level) {
 231         case 2:
 232                 base = &state->r.out.validation.sam2->base;
 233                 break;
 234         case 3:
 235                 base = &state->r.out.validation.sam3->base;
 236                 break;
 237         case 6:
 238                 base = &state->r.out.validation.sam6->base;
 239                 break;
 240         }
 241         if (base == NULL) {
 242                 composite_error(state->ctx, NT_STATUS_INTERNAL_ERROR);
 243                 return;
 244         }
 245
 246         state->user_session_key = base->key;
 247         state->lm_key = base->LMSessKey;
 248
 249         /* Give the caller the most accurate username possible.
 250          * Assists where case sensitive comparisons may be done by our
 251          * ntlm_auth callers */
 252         if (base->account_name.string) {
 253                 state->user_name = base->account_name.string;
 254                 talloc_steal(state, base->account_name.string);
 255         }
 256         if (base->domain.string) {
 257                 state->domain_name = base->domain.string;
 258                 talloc_steal(state, base->domain.string);
 259         }
 260
 261         state->unix_username = talloc_asprintf(state, "%s%s%s",
 262                                                state->domain_name,
 263                                                lp_winbind_separator(),
 264                                                state->user_name);
 265         if (composite_nomem(state->unix_username, state->ctx)) return;
 266
 267         composite_done(state->ctx);
 268 }
 269
 270 NTSTATUS wb_cmd_pam_auth_crap_recv(struct composite_context *c,
 271                                    TALLOC_CTX *mem_ctx,
 272                                    DATA_BLOB *info3,
 273                                    struct netr_UserSessionKey *user_session_key,
 274                                    struct netr_LMSessionKey *lm_key,
 275                                    char **unix_username)
 276 {
 277         struct pam_auth_crap_state *state =
 278                 talloc_get_type(c->private_data, struct pam_auth_crap_state);
 279         NTSTATUS status = composite_wait(c);
 280         if (NT_STATUS_IS_OK(status)) {
 281                 info3->length = state->info3.length;
 282                 info3->data = talloc_steal(mem_ctx, state->info3.data);
 283                 *user_session_key = state->user_session_key;
 284                 *lm_key = state->lm_key;
 285                 *unix_username = talloc_steal(mem_ctx, state->unix_username);
 286         }
 287         talloc_free(state);
 288         return status;
 289 }
 290
 291 NTSTATUS wb_cmd_pam_auth_crap(TALLOC_CTX *mem_ctx,
 292                               struct wbsrv_service *service,
 293                               uint32_t logon_parameters,
 294                               const char *domain, const char *user,
 295                               const char *workstation,
 296                               DATA_BLOB chal, DATA_BLOB nt_resp,
 297                               DATA_BLOB lm_resp,
 298                               DATA_BLOB *info3,
 299                               struct netr_UserSessionKey *user_session_key,
 300                               struct netr_LMSessionKey *lm_key,
 301                               char **unix_username)
 302 {
 303         struct composite_context *c =
 304                 wb_cmd_pam_auth_crap_send(mem_ctx, service, logon_parameters,
 305                                           domain, user, workstation,
 306                                           chal, nt_resp, lm_resp);
 307         return wb_cmd_pam_auth_crap_recv(c, mem_ctx, info3, user_session_key,
 308                                          lm_key, unix_username);
 309 }
 310
 311 struct composite_context *wb_cmd_pam_auth_send(TALLOC_CTX *mem_ctx,
 312                                                struct wbsrv_service *service,
 313                                                const char *domain,
 314                                                const char *user,
 315                                                const char *password)
 316 {
 317         struct cli_credentials *credentials;
 318         const char *workstation;
 319         NTSTATUS status;
 320
 321         DATA_BLOB chal, nt_resp, lm_resp, names_blob;
 322         int flags = CLI_CRED_NTLM_AUTH;
 323         if (lp_client_lanman_auth()) {
 324                 flags |= CLI_CRED_LANMAN_AUTH;
 325         }
 326
 327         if (lp_client_ntlmv2_auth()) {
 328                 flags |= CLI_CRED_NTLMv2_AUTH;
 329         }
 330
 331         DEBUG(5, ("wbsrv_samba3_pam_auth called\n"));
 332
 333         credentials = cli_credentials_init(mem_ctx);
 334         if (!credentials) {
 335                 return NULL;
 336         }
 337         cli_credentials_set_conf(credentials);
 338         cli_credentials_set_domain(credentials, domain, CRED_SPECIFIED);
 339         cli_credentials_set_username(credentials, user, CRED_SPECIFIED);
 340
 341         cli_credentials_set_password(credentials, password, CRED_SPECIFIED);
 342
 343         chal = data_blob_talloc(mem_ctx, NULL, 8);
 344         if (!chal.data) {
 345                 return NULL;
 346         }
 347         generate_random_buffer(chal.data, chal.length);
 348         cli_credentials_get_ntlm_username_domain(credentials, mem_ctx,
 349                                                  &user, &domain);
 350         /* for best compatability with multiple vitual netbios names
 351          * on the host, this should be generated from the
 352          * cli_credentials associated with the machine account */
 353         workstation = cli_credentials_get_workstation(credentials);
 354
 355         names_blob = NTLMv2_generate_names_blob(
 356                 mem_ctx,
 357                 cli_credentials_get_workstation(credentials),
 358                 cli_credentials_get_domain(credentials));
 359
 360         status = cli_credentials_get_ntlm_response(
 361                 credentials, mem_ctx, &flags, chal, names_blob,
 362                 &lm_resp, &nt_resp, NULL, NULL);
 363         if (!NT_STATUS_IS_OK(status)) {
 364                 return NULL;
 365         }
 366         return wb_cmd_pam_auth_crap_send(mem_ctx, service,
 367                                          0 /* logon parameters */,
 368                                          domain, user, workstation,
 369                                          chal, nt_resp, lm_resp);
 370 }
 371
 372 NTSTATUS wb_cmd_pam_auth_recv(struct composite_context *c)
 373 {
 374         struct pam_auth_crap_state *state =
 375                 talloc_get_type(c->private_data, struct pam_auth_crap_state);
 376         NTSTATUS status = composite_wait(c);
 377         talloc_free(state);
 378         return status;
 379 }
 380
 381 NTSTATUS wb_cmd_pam_auth(TALLOC_CTX *mem_ctx, struct wbsrv_service *service,
 382                          const char *domain, const char *user,
 383                          const char *password)
 384 {
 385         struct composite_context *c =
 386                 wb_cmd_pam_auth_send(mem_ctx, service, domain, user, password);
 387         return wb_cmd_pam_auth_recv(c);
 388 }