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