summaryrefslogtreecommitdiffstats
path: root/src/providers/krb5/krb5_access.c
blob: afa3a89df2932ec18984733009f3339e62046673 (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
/*
    SSSD

    Kerberos 5 Backend Module - access control

    Authors:
        Sumit Bose <sbose@redhat.com>

    Copyright (C) 2010 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 "util/util.h"
#include "providers/krb5/krb5_auth.h"
#include "providers/krb5/krb5_common.h"

struct krb5_access_state {
    struct tevent_context *ev;
    struct be_ctx *be_ctx;

    struct pam_data *pd;
    struct krb5_ctx *krb5_ctx;
    struct krb5child_req *kr;

    bool access_allowed;
};

static void krb5_access_child_done(struct tevent_req *subreq);
struct tevent_req *krb5_access_send(TALLOC_CTX *mem_ctx,
                                    struct tevent_context *ev,
                                    struct be_ctx *be_ctx,
                                    struct pam_data *pd,
                                    struct krb5_ctx *krb5_ctx)
{
    struct krb5_access_state *state;
    struct tevent_req *req;
    struct tevent_req *subreq;
    int ret;
    const char **attrs;
    struct ldb_result *res;

    req = tevent_req_create(mem_ctx, &state, struct krb5_access_state);
    if (req == NULL) {
        DEBUG(1, ("tevent_req_create failed.\n"));
        return NULL;
    }

    state->ev = ev;
    state->be_ctx = be_ctx;
    state->pd = pd;
    state->krb5_ctx = krb5_ctx;
    state->access_allowed = false;

    ret = krb5_setup(state, pd, krb5_ctx, &state->kr);
    if (ret != EOK) {
        DEBUG(1, ("krb5_setup failed.\n"));
        goto done;
    }

    if (pd->cmd != SSS_PAM_ACCT_MGMT) {
        DEBUG(1, ("Unexpected pam task.\n"));
        ret = EINVAL;
        goto done;
    }

    attrs = talloc_array(state, const char *, 4);
    if (attrs == NULL) {
        DEBUG(1, ("talloc_array failed.\n"));
        ret = ENOMEM;
        goto done;
    }

    attrs[0] = SYSDB_UPN;
    attrs[1] = SYSDB_UIDNUM;
    attrs[2] = SYSDB_GIDNUM;
    attrs[3] = NULL;

    ret = sysdb_get_user_attr(state, be_ctx->sysdb, state->pd->user, attrs,
                              &res);
    if (ret) {
        DEBUG(5, ("sysdb search for upn of user [%s] failed.\n", pd->user));
        goto done;
    }

    switch (res->count) {
    case 0:
        DEBUG(5, ("No attributes for user [%s] found.\n", pd->user));
        ret = ENOENT;
        goto done;
        break;
    case 1:
        state->kr->upn = ldb_msg_find_attr_as_string(res->msgs[0], SYSDB_UPN,
                                                     NULL);
        if (state->kr->upn == NULL) {
            ret = krb5_get_simple_upn(state, krb5_ctx, pd->user,
                                      &state->kr->upn);
            if (ret != EOK) {
                DEBUG(1, ("krb5_get_simple_upn failed.\n"));
                goto done;
            }
        }

        state->kr->uid = ldb_msg_find_attr_as_uint64(res->msgs[0], SYSDB_UIDNUM,
                                                     0);
        if (state->kr->uid == 0) {
            DEBUG(4, ("UID for user [%s] not known.\n", pd->user));
            ret = ENOENT;
            goto done;
        }

        state->kr->gid = ldb_msg_find_attr_as_uint64(res->msgs[0], SYSDB_GIDNUM,
                                                     0);
        if (state->kr->gid == 0) {
            DEBUG(4, ("GID for user [%s] not known.\n", pd->user));
            ret = ENOENT;
            goto done;
        }

        break;
    default:
        DEBUG(1, ("User search for [%s] returned > 1 results!\n", pd->user));
        ret = EINVAL;
        goto done;
        break;
    }

    subreq = handle_child_send(state, state->ev, state->kr);
    if (subreq == NULL) {
        DEBUG(1, ("handle_child_send failed.\n"));
        ret = ENOMEM;
        goto done;
    }

    tevent_req_set_callback(subreq, krb5_access_child_done, req);
    return req;

done:
    if (ret == EOK) {
        tevent_req_done(req);
    } else {
        tevent_req_error(req, ret);
    }
    tevent_req_post(req, state->ev);
    return req;
}

static void krb5_access_child_done(struct tevent_req *subreq)
{
    struct tevent_req *req = tevent_req_callback_data(subreq, struct tevent_req);
    struct krb5_access_state *state = tevent_req_data(req,
                                                      struct krb5_access_state);
    int ret;
    uint8_t *buf = NULL;
    ssize_t len = -1;
    int32_t msg_status;

    ret = handle_child_recv(subreq, state, &buf, &len);
    talloc_free(subreq);
    if (ret != EOK) {
        DEBUG(1, ("child failed [%d][%s].\n", ret, strerror(ret)));
        goto fail;
    }

    if ((size_t) len != sizeof(int32_t)) {
        DEBUG(1, ("message has the wrong size.\n"));
        ret = EINVAL;
        goto fail;
    }

    SAFEALIGN_COPY_INT32(&msg_status, buf, NULL);

    if (msg_status == EOK) {
        state->access_allowed = true;
    } else {
        state->access_allowed = false;
    }

    tevent_req_done(req);
    return;

fail:
    tevent_req_error(req, ret);
    return;
}

int krb5_access_recv(struct tevent_req *req, bool *access_allowed)
{
    struct krb5_access_state *state = tevent_req_data(req,
                                                      struct krb5_access_state);

    TEVENT_REQ_RETURN_ON_ERROR(req);

    *access_allowed = state->access_allowed;

    return EOK;
}