2 * Copyright (c) 2001 Markus Friedl. All rights reserved.
3 * Copyright (c) 2001 Per Allansson. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 RCSID("$OpenBSD: auth2-chall.c,v 1.20 2002/06/30 21:59:45 deraadt Exp $");
27 RCSID("$FreeBSD: src/crypto/openssh/auth2-chall.c,v 1.1.1.1.2.3 2003/02/03 17:31:06 des Exp $");
28 RCSID("$DragonFly: src/crypto/openssh/Attic/auth2-chall.c,v 1.2 2003/06/17 04:24:36 dillon Exp $");
39 static int auth2_challenge_start(Authctxt *);
40 static int send_userauth_info_request(Authctxt *);
41 static void input_userauth_info_response(int, u_int32_t, void *);
44 extern KbdintDevice bsdauth_device;
47 extern KbdintDevice pam_device;
50 extern KbdintDevice skey_device;
54 KbdintDevice *devices[] = {
68 typedef struct KbdintAuthctxt KbdintAuthctxt;
77 static KbdintAuthctxt *
78 kbdint_alloc(const char *devs)
80 KbdintAuthctxt *kbdintctxt;
84 kbdintctxt = xmalloc(sizeof(KbdintAuthctxt));
85 if (strcmp(devs, "") == 0) {
87 for (i = 0; devices[i]; i++) {
88 if (buffer_len(&b) > 0)
89 buffer_append(&b, ",", 1);
90 buffer_append(&b, devices[i]->name,
91 strlen(devices[i]->name));
93 buffer_append(&b, "\0", 1);
94 kbdintctxt->devices = xstrdup(buffer_ptr(&b));
97 kbdintctxt->devices = xstrdup(devs);
99 debug("kbdint_alloc: devices '%s'", kbdintctxt->devices);
100 kbdintctxt->ctxt = NULL;
101 kbdintctxt->device = NULL;
102 kbdintctxt->nreq = 0;
107 kbdint_reset_device(KbdintAuthctxt *kbdintctxt)
109 if (kbdintctxt->ctxt) {
110 kbdintctxt->device->free_ctx(kbdintctxt->ctxt);
111 kbdintctxt->ctxt = NULL;
113 kbdintctxt->device = NULL;
116 kbdint_free(KbdintAuthctxt *kbdintctxt)
118 if (kbdintctxt->device)
119 kbdint_reset_device(kbdintctxt);
120 if (kbdintctxt->devices) {
121 xfree(kbdintctxt->devices);
122 kbdintctxt->devices = NULL;
126 /* get next device */
128 kbdint_next_device(KbdintAuthctxt *kbdintctxt)
134 if (kbdintctxt->device)
135 kbdint_reset_device(kbdintctxt);
137 len = kbdintctxt->devices ?
138 strcspn(kbdintctxt->devices, ",") : 0;
142 for (i = 0; devices[i]; i++)
143 if (strncmp(kbdintctxt->devices, devices[i]->name, len) == 0)
144 kbdintctxt->device = devices[i];
145 t = kbdintctxt->devices;
146 kbdintctxt->devices = t[len] ? xstrdup(t+len+1) : NULL;
148 debug2("kbdint_next_device: devices %s", kbdintctxt->devices ?
149 kbdintctxt->devices : "<empty>");
150 } while (kbdintctxt->devices && !kbdintctxt->device);
152 return kbdintctxt->device ? 1 : 0;
156 * try challenge-response, set authctxt->postponed if we have to
157 * wait for the response.
160 auth2_challenge(Authctxt *authctxt, char *devs)
162 debug("auth2_challenge: user=%s devs=%s",
163 authctxt->user ? authctxt->user : "<nouser>",
164 devs ? devs : "<no devs>");
166 if (authctxt->user == NULL || !devs)
168 if (authctxt->kbdintctxt == NULL)
169 authctxt->kbdintctxt = kbdint_alloc(devs);
170 return auth2_challenge_start(authctxt);
173 /* unregister kbd-int callbacks and context */
175 auth2_challenge_stop(Authctxt *authctxt)
177 /* unregister callback */
178 dispatch_set(SSH2_MSG_USERAUTH_INFO_RESPONSE, NULL);
179 if (authctxt->kbdintctxt != NULL) {
180 kbdint_free(authctxt->kbdintctxt);
181 authctxt->kbdintctxt = NULL;
185 /* side effect: sets authctxt->postponed if a reply was sent*/
187 auth2_challenge_start(Authctxt *authctxt)
189 KbdintAuthctxt *kbdintctxt = authctxt->kbdintctxt;
191 debug2("auth2_challenge_start: devices %s",
192 kbdintctxt->devices ? kbdintctxt->devices : "<empty>");
194 if (kbdint_next_device(kbdintctxt) == 0) {
195 auth2_challenge_stop(authctxt);
198 debug("auth2_challenge_start: trying authentication method '%s'",
199 kbdintctxt->device->name);
201 if ((kbdintctxt->ctxt = kbdintctxt->device->init_ctx(authctxt)) == NULL) {
202 auth2_challenge_stop(authctxt);
205 if (send_userauth_info_request(authctxt) == 0) {
206 auth2_challenge_stop(authctxt);
209 dispatch_set(SSH2_MSG_USERAUTH_INFO_RESPONSE,
210 &input_userauth_info_response);
212 authctxt->postponed = 1;
217 send_userauth_info_request(Authctxt *authctxt)
219 KbdintAuthctxt *kbdintctxt;
220 char *name, *instr, **prompts;
224 kbdintctxt = authctxt->kbdintctxt;
225 if (kbdintctxt->device->query(kbdintctxt->ctxt,
226 &name, &instr, &kbdintctxt->nreq, &prompts, &echo_on))
229 packet_start(SSH2_MSG_USERAUTH_INFO_REQUEST);
230 packet_put_cstring(name);
231 packet_put_cstring(instr);
232 packet_put_cstring(""); /* language not used */
233 packet_put_int(kbdintctxt->nreq);
234 for (i = 0; i < kbdintctxt->nreq; i++) {
235 packet_put_cstring(prompts[i]);
236 packet_put_char(echo_on[i]);
241 for (i = 0; i < kbdintctxt->nreq; i++)
251 input_userauth_info_response(int type, u_int32_t seq, void *ctxt)
253 Authctxt *authctxt = ctxt;
254 KbdintAuthctxt *kbdintctxt;
255 int i, authenticated = 0, res, len;
257 char **response = NULL, *method;
259 if (authctxt == NULL)
260 fatal("input_userauth_info_response: no authctxt");
261 kbdintctxt = authctxt->kbdintctxt;
262 if (kbdintctxt == NULL || kbdintctxt->ctxt == NULL)
263 fatal("input_userauth_info_response: no kbdintctxt");
264 if (kbdintctxt->device == NULL)
265 fatal("input_userauth_info_response: no device");
267 authctxt->postponed = 0; /* reset */
268 nresp = packet_get_int();
269 if (nresp != kbdintctxt->nreq)
270 fatal("input_userauth_info_response: wrong number of replies");
272 fatal("input_userauth_info_response: too many replies");
274 response = xmalloc(nresp * sizeof(char *));
275 for (i = 0; i < nresp; i++)
276 response[i] = packet_get_string(NULL);
280 if (authctxt->valid) {
281 res = kbdintctxt->device->respond(kbdintctxt->ctxt,
287 for (i = 0; i < nresp; i++) {
288 memset(response[i], 'r', strlen(response[i]));
300 /* Authentication needs further interaction */
301 if (send_userauth_info_request(authctxt) == 1)
302 authctxt->postponed = 1;
309 len = strlen("keyboard-interactive") + 2 +
310 strlen(kbdintctxt->device->name);
311 method = xmalloc(len);
312 snprintf(method, len, "keyboard-interactive/%s",
313 kbdintctxt->device->name);
315 if (!authctxt->postponed) {
317 auth2_challenge_stop(authctxt);
319 /* start next device */
320 /* may set authctxt->postponed */
321 auth2_challenge_start(authctxt);
324 userauth_finish(authctxt, authenticated, method);
329 privsep_challenge_enable(void)
332 extern KbdintDevice mm_bsdauth_device;
335 extern KbdintDevice mm_pam_device;
338 extern KbdintDevice mm_skey_device;
343 devices[n++] = &mm_bsdauth_device;
346 devices[n++] = &mm_pam_device;
349 devices[n++] = &mm_skey_device;