summaryrefslogtreecommitdiff
path: root/src/sss_client/sssd_pac.c
blob: 469758a65c1ec3502becb48175753a965a48773c (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
/*
    Authors:
        Sumit Bose <sbose@redhat.com>

    Copyright (C) 2011, 2012, 2013 Red Hat

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU Lesser 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 Lesser General Public License for more details.

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

/* A short documentation about authdata plugins can be found in
 * http://http://k5wiki.kerberos.org/wiki/Projects/VerifyAuthData */

#include <krb5/krb5.h>
#include <errno.h>

#include "krb5_authdata_int.h"
#include "sss_cli.h"


struct sssd_context {
    krb5_data data;
};

static krb5_error_code
sssdpac_init(krb5_context kcontext, void **plugin_context)
{
    *plugin_context = NULL;
    return 0;
}

static void
sssdpac_flags(krb5_context kcontext,
              void *plugin_context,
              krb5_authdatatype ad_type,
              krb5_flags *flags)
{
    *flags = AD_USAGE_KDC_ISSUED | AD_USAGE_TGS_REQ;
}

static void
sssdpac_fini(krb5_context kcontext, void *plugin_context)
{
    return;
}

static krb5_error_code
sssdpac_request_init(krb5_context kcontext,
                     krb5_authdata_context context,
                     void *plugin_context,
                     void **request_context)
{
    struct sssd_context *sssdctx;

    sssdctx = (struct sssd_context *)calloc(1, sizeof(*sssdctx));
    if (sssdctx == NULL) {
        return ENOMEM;
    }

    *request_context = sssdctx;

    return 0;
}

static krb5_error_code
sssdpac_import_authdata(krb5_context kcontext,
                        krb5_authdata_context context,
                        void *plugin_context,
                        void *request_context,
                        krb5_authdata **authdata,
                        krb5_boolean kdc_issued,
                        krb5_const_principal kdc_issuer)
{
    char *data = NULL;
    struct sssd_context *sssdctx = (struct sssd_context *)request_context;

    if (authdata[0] == NULL) {
        return EINVAL;
    }

    if (authdata[0]->length > 0) {
        data = malloc(sizeof(char) * authdata[0]->length);
        if (data == NULL) {
            return ENOMEM;
        }
        memcpy(data, authdata[0]->contents, authdata[0]->length);
    }

    if (sssdctx->data.data != NULL) {
        krb5_free_data_contents(kcontext, &sssdctx->data);
    }

    sssdctx->data.length = authdata[0]->length;
    sssdctx->data.data = data;
    return 0;
}

static void
sssdpac_request_fini(krb5_context kcontext,
                     krb5_authdata_context context,
                     void *plugin_context,
                     void *request_context)
{
    struct sssd_context *sssdctx = (struct sssd_context *)request_context;

    if (sssdctx != NULL) {
        if (sssdctx->data.data != NULL) {
            krb5_free_data_contents(kcontext, &sssdctx->data);
        }

        free(sssdctx);
    }
}

static krb5_error_code sssdpac_verify(krb5_context kcontext,
                                      krb5_authdata_context context,
                                      void *plugin_context,
                                      void *request_context,
                                      const krb5_auth_context *auth_context,
                                      const krb5_keyblock *key,
                                      const krb5_ap_req *req)
{
    krb5_error_code kerr;
    int ret;
    krb5_pac pac;
    struct sssd_context *sssdctx = (struct sssd_context *)request_context;
    struct sss_cli_req_data sss_data;
    int errnop;

    if (sssdctx == NULL || sssdctx->data.data == NULL) {
        return EINVAL;
    }

    kerr = krb5_pac_parse(kcontext, sssdctx->data.data,
                          sssdctx->data.length, &pac);
    if (kerr != 0) {
        return EINVAL;
    }

    kerr = krb5_pac_verify(kcontext, pac,
                           req->ticket->enc_part2->times.authtime,
                           req->ticket->enc_part2->client, key, NULL);
    if (kerr != 0) {
        return EINVAL;
    }

    sss_data.len = sssdctx->data.length;
    sss_data.data = sssdctx->data.data;

    ret = sss_pac_make_request(SSS_PAC_ADD_PAC_USER, &sss_data,
                               NULL, NULL, &errnop);
    if (ret != 0) {
        /* Ignore the error */
    }

    return 0;
}

static krb5_error_code
sssdpac_size(krb5_context kcontext,
             krb5_authdata_context context,
             void *plugin_context,
             void *request_context,
             size_t *sizep)
{
    struct sssd_context *sssdctx = (struct sssd_context *)request_context;

    *sizep += sizeof(krb5_int32);

    *sizep += sssdctx->data.length;

    *sizep += sizeof(krb5_int32);

    return 0;
}

static krb5_error_code
sssdpac_externalize(krb5_context kcontext,
                    krb5_authdata_context context,
                    void *plugin_context,
                    void *request_context,
                    krb5_octet **buffer,
                    size_t *lenremain)
{
    krb5_error_code code = 0;
    struct sssd_context *sssdctx = (struct sssd_context *)request_context;
    size_t required = 0;
    krb5_octet *bp;
    size_t remain;

    bp = *buffer;
    remain = *lenremain;

    if (sssdctx->data.data != NULL) {
        sssdpac_size(kcontext, context, plugin_context,
                   request_context, &required);

        if (required <= remain) {
            krb5_ser_pack_int32((krb5_int32)sssdctx->data.length,
                                &bp, &remain);
            krb5_ser_pack_bytes((krb5_octet *)sssdctx->data.data,
                                (size_t)sssdctx->data.length,
                                &bp, &remain);
            krb5_ser_pack_int32(0,
                                &bp, &remain);
        } else {
            code = ENOMEM;
        }
    } else {
        krb5_ser_pack_int32(0, &bp, &remain); /* length */
        krb5_ser_pack_int32(0, &bp, &remain); /* verified */
    }

    *buffer = bp;
    *lenremain = remain;

    return code;
}

static krb5_error_code
sssdpac_internalize(krb5_context kcontext,
                    krb5_authdata_context context,
                    void *plugin_context,
                    void *request_context,
                    krb5_octet **buffer,
                    size_t *lenremain)
{
    struct sssd_context *sssdctx = (struct sssd_context *)request_context;
    krb5_error_code code;
    krb5_int32 ibuf;
    krb5_octet *bp;
    size_t remain;
    krb5_data data;

    bp = *buffer;
    remain = *lenremain;

    /* length */
    code = krb5_ser_unpack_int32(&ibuf, &bp, &remain);
    if (code != 0) {
        return code;
    }

    if (ibuf != 0) {

        data.length = ibuf;
        data.data = malloc(sizeof(char) * ibuf);
        if (data.data == NULL) {
            return ENOMEM;
        }
        memcpy(data.data, bp, ibuf);

        bp += ibuf;
        remain -= ibuf;
    } else {
        data.length = 0;
        data.data = NULL;
    }

    /* verified */
    code = krb5_ser_unpack_int32(&ibuf, &bp, &remain);
    if (code != 0) {
        return code;
    }

    if (sssdctx->data.data != NULL) {
        krb5_free_data_contents(kcontext, &sssdctx->data);
    }

    sssdctx->data.length = data.length;
    sssdctx->data.data = data.data;

    *buffer = bp;
    *lenremain = remain;

    return 0;
}

static krb5_authdatatype sssdpac_ad_types[] = { KRB5_AUTHDATA_WIN2K_PAC, 0 };

krb5plugin_authdata_client_ftable_v0 authdata_client_0 = {
    ((void *)((uintptr_t)("sssd_sssdpac"))),
    sssdpac_ad_types,
    sssdpac_init,
    sssdpac_fini,
    sssdpac_flags,
    sssdpac_request_init,
    sssdpac_request_fini,
    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
    sssdpac_import_authdata,
    NULL,
    NULL,
    sssdpac_verify,
    sssdpac_size,
    sssdpac_externalize,
    sssdpac_internalize,
    NULL
};