summaryrefslogtreecommitdiff
path: root/src/providers/ipa/ipa_auth.c
blob: f0bdd429ea9c99cb345057369835d8126a935b07 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
/*
    SSSD

    IPA Backend Module -- Authentication

    Authors:
        Sumit Bose <sbose@redhat.com>

    Copyright (C) 2009 Red Hat

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <sys/param.h>
#include <security/pam_modules.h>

#include "util/util.h"
#include "providers/ldap/ldap_common.h"
#include "providers/ldap/sdap_async.h"
#include "providers/krb5/krb5_auth.h"
#include "providers/ipa/ipa_common.h"

#define IPA_CONFIG_MIRATION_ENABLED "ipaMigrationEnabled"
#define IPA_CONFIG_SEARCH_BASE_TEMPLATE "cn=etc,%s"
#define IPA_CONFIG_FILTER "(&(cn=ipaConfig)(objectClass=ipaGuiConfig))"

static void ipa_auth_reply(struct be_req *be_req, int dp_err, int result)
{
    be_req->fn(be_req, dp_err, result, NULL);
}

struct get_password_migration_flag_state {
    struct tevent_context *ev;
    struct sdap_auth_ctx *sdap_auth_ctx;
    struct sdap_handle *sh;
    enum sdap_result result;
    struct fo_server *srv;
    char *ipa_realm;
    bool password_migration;
};

static void get_password_migration_flag_auth_done(struct tevent_req *subreq);
static void get_password_migration_flag_done(struct tevent_req *subreq);

static struct tevent_req *get_password_migration_flag_send(TALLOC_CTX *memctx,
                                            struct tevent_context *ev,
                                            struct sdap_auth_ctx *sdap_auth_ctx,
                                            char *ipa_realm)
{
    int ret;
    struct tevent_req *req, *subreq;
    struct get_password_migration_flag_state *state;

    if (sdap_auth_ctx == NULL || ipa_realm == NULL) {
        DEBUG(1, ("Missing parameter.\n"));
        return NULL;
    }

    req = tevent_req_create(memctx, &state,
                            struct get_password_migration_flag_state);
    if (req == NULL) {
        DEBUG(1, ("tevent_req_create failed.\n"));
        return NULL;
    }

    state->ev = ev;
    state->sdap_auth_ctx = sdap_auth_ctx;
    state->sh = NULL;
    state->result = SDAP_ERROR;
    state->srv = NULL;
    state->password_migration = false;
    state->ipa_realm = ipa_realm;

    /* We request to use StartTLS here, because if password migration is
     * enabled we will use this connection for authentication, too. */
    ret = dp_opt_set_bool(sdap_auth_ctx->opts->basic, SDAP_ID_TLS, true);
    if (ret != EOK) {
        DEBUG(1, ("Failed to set SDAP_ID_TLS to true.\n"));
        goto fail;
    }

    subreq = sdap_cli_connect_send(state, ev, sdap_auth_ctx->opts,
                                   sdap_auth_ctx->be, sdap_auth_ctx->service,
                                   true);
    if (subreq == NULL) {
        DEBUG(1, ("sdap_cli_connect_send failed.\n"));
        goto fail;
    }
    tevent_req_set_callback(subreq, get_password_migration_flag_auth_done,
                            req);

    return req;

fail:
    talloc_zfree(req);
    return NULL;
}

static void get_password_migration_flag_auth_done(struct tevent_req *subreq)
{
    struct tevent_req *req = tevent_req_callback_data(subreq,
                                                      struct tevent_req);
    struct get_password_migration_flag_state *state = tevent_req_data(req,
                                      struct get_password_migration_flag_state);
    int ret;
    char *ldap_basedn;
    char *search_base;
    const char **attrs;

    ret = sdap_cli_connect_recv(subreq, state, NULL, &state->sh, NULL);
    talloc_zfree(subreq);
    if (ret) {
        DEBUG(1, ("sdap_auth request failed.\n"));
        tevent_req_error(req, ret);
        return;
    }

    ret = domain_to_basedn(state, state->ipa_realm, &ldap_basedn);
    if (ret != EOK) {
        DEBUG(1, ("domain_to_basedn failed.\n"));
        tevent_req_error(req, ret);
        return;
    }

    search_base = talloc_asprintf(state, IPA_CONFIG_SEARCH_BASE_TEMPLATE,
                                  ldap_basedn);
    if (search_base == NULL) {
        DEBUG(1, ("talloc_asprintf failed.\n"));
        tevent_req_error(req, ENOMEM);
        return;
    }

    attrs = talloc_array(state, const char*, 2);
    if (attrs == NULL) {
        DEBUG(1, ("talloc_array failed.\n"));
        tevent_req_error(req, ENOMEM);
        return;
    }

    attrs[0] = IPA_CONFIG_MIRATION_ENABLED;
    attrs[1] = NULL;

    subreq = sdap_get_generic_send(state, state->ev, state->sdap_auth_ctx->opts,
                                   state->sh, search_base, LDAP_SCOPE_SUBTREE,
                                   IPA_CONFIG_FILTER, attrs, NULL, 0,
                                   dp_opt_get_int(state->sdap_auth_ctx->opts->basic,
                                                  SDAP_SEARCH_TIMEOUT));
    if (!subreq) {
        tevent_req_error(req, ENOMEM);
        return;
    }

    tevent_req_set_callback(subreq, get_password_migration_flag_done, req);
}

static void get_password_migration_flag_done(struct tevent_req *subreq)
{
    struct tevent_req *req = tevent_req_callback_data(subreq,
                                                      struct tevent_req);
    struct get_password_migration_flag_state *state = tevent_req_data(req,
                                      struct get_password_migration_flag_state);
    int ret;
    size_t reply_count;
    struct sysdb_attrs **reply = NULL;
    const char *value = NULL;

    ret = sdap_get_generic_recv(subreq, state, &reply_count, &reply);
    talloc_zfree(subreq);
    if (ret) {
        tevent_req_error(req, ret);
        return;
    }

    if (reply_count != 1) {
        DEBUG(1, ("Unexpected number of results, expected 1, got %d.\n",
                  reply_count));
        tevent_req_error(req, EINVAL);
        return;
    }

    ret = sysdb_attrs_get_string(reply[0], IPA_CONFIG_MIRATION_ENABLED, &value);
    if (ret == EOK && strcasecmp(value, "true") == 0) {
        state->password_migration = true;
    }

    tevent_req_done(req);
}

static int get_password_migration_flag_recv(struct tevent_req *req,
                                            TALLOC_CTX *mem_ctx,
                                            bool *password_migration,
                                            struct sdap_handle **sh)
{
    struct get_password_migration_flag_state *state = tevent_req_data(req,
                                      struct get_password_migration_flag_state);

    TEVENT_REQ_RETURN_ON_ERROR(req);

    *password_migration = state->password_migration;
    if (sh != NULL) {
        *sh = talloc_steal(mem_ctx, state->sh);
    }

    return EOK;
}


struct ipa_auth_state {
    struct be_req *be_req;
    struct tevent_context *ev;
    struct ipa_auth_ctx *ipa_auth_ctx;
    struct pam_data *pd;
    bool password_migration;
    struct sdap_handle *sh;
};

static void ipa_auth_handler_done(struct tevent_req *req);
static void ipa_get_migration_flag_done(struct tevent_req *req);
static void ipa_auth_ldap_done(struct tevent_req *req);
static void ipa_auth_handler_retry_done(struct tevent_req *req);

void ipa_auth(struct be_req *be_req)
{
    struct tevent_req *req;
    struct ipa_auth_state *state;
    struct pam_data *pd = talloc_get_type(be_req->req_data, struct pam_data);

    state = talloc_zero(be_req, struct ipa_auth_state);
    if (state == NULL) {
        DEBUG(1, ("talloc_zero failed.\n"));
        goto fail;
    }

    state->password_migration = false;
    state->sh = NULL;

    state->be_req = be_req;
    state->ev = be_req->be_ctx->ev;

    state->pd = pd;

    switch (state->pd->cmd) {
        case SSS_PAM_AUTHENTICATE:
            state->ipa_auth_ctx = talloc_get_type(
                                be_req->be_ctx->bet_info[BET_AUTH].pvt_bet_data,
                                struct ipa_auth_ctx);
            break;
        case SSS_PAM_CHAUTHTOK:
        case SSS_PAM_CHAUTHTOK_PRELIM:
            state->ipa_auth_ctx = talloc_get_type(
                              be_req->be_ctx->bet_info[BET_CHPASS].pvt_bet_data,
                              struct ipa_auth_ctx);
            break;
        default:
            DEBUG(1, ("Unsupported PAM task.\n"));
            goto fail;
    }

    req = krb5_auth_send(state, state->ev, be_req->be_ctx, state->pd,
                         state->ipa_auth_ctx->krb5_auth_ctx);
    if (req == NULL) {
        DEBUG(1, ("krb5_auth_send failed.\n"));
        goto fail;
    }

    tevent_req_set_callback(req, ipa_auth_handler_done, state);
    return;

fail:
    talloc_free(state);
    pd->pam_status = PAM_SYSTEM_ERR;
    ipa_auth_reply(be_req, DP_ERR_FATAL, pd->pam_status);
}

static void ipa_auth_handler_done(struct tevent_req *req)
{
    struct ipa_auth_state *state = tevent_req_callback_data(req,
                                                         struct ipa_auth_state);
    int ret;
    int pam_status = PAM_SYSTEM_ERR;
    int dp_err;

    ret = krb5_auth_recv(req, &pam_status, &dp_err);
    talloc_zfree(req);
    state->pd->pam_status = pam_status;
    if (ret != EOK && pam_status != PAM_CRED_ERR) {
        DEBUG(1, ("krb5_auth_recv request failed.\n"));
        dp_err = DP_ERR_OK;
        goto done;
    }

    if (dp_err != DP_ERR_OK) {
        goto done;
    }

    if (state->pd->cmd == SSS_PAM_AUTHENTICATE &&
        state->pd->pam_status == PAM_CRED_ERR) {

        req = get_password_migration_flag_send(state, state->ev,
                                             state->ipa_auth_ctx->sdap_auth_ctx,
                                             dp_opt_get_string(
                                               state->ipa_auth_ctx->ipa_options,
                                               IPA_KRB5_REALM));
        if (req == NULL) {
            DEBUG(1, ("get_password_migration_flag failed.\n"));
            goto done;
        }

        tevent_req_set_callback(req, ipa_get_migration_flag_done, state);
        return;
    }

done:
    ipa_auth_reply(state->be_req, dp_err, state->pd->pam_status);
}

static void ipa_get_migration_flag_done(struct tevent_req *req)
{
    struct ipa_auth_state *state = tevent_req_callback_data(req,
                                                         struct ipa_auth_state);
    int ret;
    int dp_err = DP_ERR_FATAL;
    const char **attrs;
    struct ldb_message *user_msg;
    const char *dn;
    struct dp_opt_blob password;

    ret = get_password_migration_flag_recv(req, state,
                                           &state->password_migration,
                                           &state->sh);
    talloc_zfree(req);
    if (ret != EOK) {
        DEBUG(1, ("get_password_migration_flag request failed.\n"));
        state->pd->pam_status = PAM_SYSTEM_ERR;
        dp_err = DP_ERR_OK;
        goto done;
    }

    if (state->password_migration) {
        state->pd->pam_status = PAM_SYSTEM_ERR;
        DEBUG(1, ("Assuming Kerberos password is missing, "
                  "starting password migration.\n"));

        attrs = talloc_array(state, const char *, 2);
        if (attrs == NULL) {
            DEBUG(1, ("talloc_array failed.\n"));
            state->pd->pam_status = PAM_SYSTEM_ERR;
            dp_err = DP_ERR_OK;
            goto done;
        }
        attrs[0] = SYSDB_ORIG_DN;
        attrs[1] = NULL;

        ret = sysdb_search_user_by_name(state, state->be_req->be_ctx->sysdb,
                                        state->pd->user, attrs, &user_msg);
        if (ret != EOK) {
            DEBUG(1, ("sysdb_search_user_by_name failed.\n"));
            goto done;
        }

        dn = ldb_msg_find_attr_as_string(user_msg, SYSDB_ORIG_DN, NULL);
        if (dn == NULL) {
            DEBUG(1, ("Missing original DN for user [%s].\n", state->pd->user));
            state->pd->pam_status = PAM_SYSTEM_ERR;
            dp_err = DP_ERR_OK;
            goto done;
        }

        password.data = state->pd->authtok;
        password.length = state->pd->authtok_size;

        req = sdap_auth_send(state, state->ev, state->sh, NULL, NULL, dn,
                             "password", password);
        if (req == NULL) {
            DEBUG(1, ("sdap_auth_send failed.\n"));
            goto done;
        }

        tevent_req_set_callback(req, ipa_auth_ldap_done, state);
        return;

    } else {
        DEBUG(5, ("Password migration is not enabled.\n"));
    }

    dp_err = DP_ERR_OK;

done:
    ipa_auth_reply(state->be_req, dp_err, state->pd->pam_status);
}

static void ipa_auth_ldap_done(struct tevent_req *req)
{
    struct ipa_auth_state *state = tevent_req_callback_data(req,
                                                         struct ipa_auth_state);
    int ret;
    int dp_err = DP_ERR_FATAL;
    enum sdap_result result;

    ret = sdap_auth_recv(req, state, &result, NULL);
    talloc_zfree(req);
    if (ret != EOK) {
        DEBUG(1, ("auth_send request failed.\n"));
        state->pd->pam_status = PAM_SYSTEM_ERR;
        dp_err = DP_ERR_OK;
        goto done;
    }

/* TODO: do we need to handle expired passwords? */
    if (result != SDAP_AUTH_SUCCESS) {
        DEBUG(1, ("LDAP authentication failed, "
                  "Password migration not possible.\n"));
        state->pd->pam_status = PAM_CRED_INSUFFICIENT;
        dp_err = DP_ERR_OK;
        goto done;
    }

    DEBUG(1, ("LDAP authentication succeded, "
              "trying Kerberos authentication again.\n"));

    req = krb5_auth_send(state, state->ev,
                         state->be_req->be_ctx, state->pd,
                         state->ipa_auth_ctx->krb5_auth_ctx);
    if (req == NULL) {
        DEBUG(1, ("krb5_auth_send failed.\n"));
        goto done;
    }

    tevent_req_set_callback(req, ipa_auth_handler_retry_done, state);
    return;

done:
    ipa_auth_reply(state->be_req, dp_err, state->pd->pam_status);
}

static void ipa_auth_handler_retry_done(struct tevent_req *req)
{
    struct ipa_auth_state *state = tevent_req_callback_data(req,
                                                         struct ipa_auth_state);
    int ret;
    int pam_status;
    int dp_err;

    ret = krb5_auth_recv(req, &pam_status, &dp_err);
    talloc_zfree(req);
    if (ret != EOK) {
        DEBUG(1, ("krb5_auth_recv request failed.\n"));
        state->pd->pam_status = PAM_SYSTEM_ERR;
        dp_err = DP_ERR_OK;
        goto done;
    }

    state->pd->pam_status = pam_status;

done:
    ipa_auth_reply(state->be_req, dp_err, state->pd->pam_status);
}