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 1.8 2001/09/27 15:31:17 markus Exp $");
36 static int auth2_challenge_start(Authctxt *);
37 static int send_userauth_info_request(Authctxt *);
38 static void input_userauth_info_response(int, int, void *);
41 extern KbdintDevice bsdauth_device;
44 extern KbdintDevice skey_device;
48 KbdintDevice *devices[] = {
59 typedef struct KbdintAuthctxt KbdintAuthctxt;
67 static KbdintAuthctxt *
68 kbdint_alloc(const char *devs)
70 KbdintAuthctxt *kbdintctxt;
74 kbdintctxt = xmalloc(sizeof(KbdintAuthctxt));
75 if (strcmp(devs, "") == 0) {
77 for (i = 0; devices[i]; i++) {
79 strlcat(buf, ",", sizeof(buf));
80 strlcat(buf, devices[i]->name, sizeof(buf));
82 debug("kbdint_alloc: devices '%s'", buf);
83 kbdintctxt->devices = xstrdup(buf);
85 kbdintctxt->devices = xstrdup(devs);
87 kbdintctxt->ctxt = NULL;
88 kbdintctxt->device = NULL;
93 kbdint_reset_device(KbdintAuthctxt *kbdintctxt)
95 if (kbdintctxt->ctxt) {
96 kbdintctxt->device->free_ctx(kbdintctxt->ctxt);
97 kbdintctxt->ctxt = NULL;
99 kbdintctxt->device = NULL;
102 kbdint_free(KbdintAuthctxt *kbdintctxt)
104 if (kbdintctxt->device)
105 kbdint_reset_device(kbdintctxt);
106 if (kbdintctxt->devices) {
107 xfree(kbdintctxt->devices);
108 kbdintctxt->devices = NULL;
112 /* get next device */
114 kbdint_next_device(KbdintAuthctxt *kbdintctxt)
120 if (kbdintctxt->device)
121 kbdint_reset_device(kbdintctxt);
123 len = kbdintctxt->devices ?
124 strcspn(kbdintctxt->devices, ",") : 0;
128 for (i = 0; devices[i]; i++)
129 if (strncmp(kbdintctxt->devices, devices[i]->name, len) == 0)
130 kbdintctxt->device = devices[i];
131 t = kbdintctxt->devices;
132 kbdintctxt->devices = t[len] ? xstrdup(t+len+1) : NULL;
134 debug2("kbdint_next_device: devices %s", kbdintctxt->devices ?
135 kbdintctxt->devices : "<empty>");
136 } while (kbdintctxt->devices && !kbdintctxt->device);
138 return kbdintctxt->device ? 1 : 0;
142 * try challenge-response, set authctxt->postponed if we have to
143 * wait for the response.
146 auth2_challenge(Authctxt *authctxt, char *devs)
148 debug("auth2_challenge: user=%s devs=%s",
149 authctxt->user ? authctxt->user : "<nouser>",
150 devs ? devs : "<no devs>");
152 if (authctxt->user == NULL || !devs)
154 if (authctxt->kbdintctxt == NULL)
155 authctxt->kbdintctxt = kbdint_alloc(devs);
156 return auth2_challenge_start(authctxt);
159 /* side effect: sets authctxt->postponed if a reply was sent*/
161 auth2_challenge_start(Authctxt *authctxt)
163 KbdintAuthctxt *kbdintctxt = authctxt->kbdintctxt;
165 debug2("auth2_challenge_start: devices %s",
166 kbdintctxt->devices ? kbdintctxt->devices : "<empty>");
168 if (kbdint_next_device(kbdintctxt) == 0) {
169 kbdint_free(kbdintctxt);
170 authctxt->kbdintctxt = NULL;
173 debug("auth2_challenge_start: trying authentication method '%s'",
174 kbdintctxt->device->name);
176 if ((kbdintctxt->ctxt = kbdintctxt->device->init_ctx(authctxt)) == NULL) {
177 kbdint_free(kbdintctxt);
178 authctxt->kbdintctxt = NULL;
181 if (send_userauth_info_request(authctxt) == 0) {
182 kbdint_free(kbdintctxt);
183 authctxt->kbdintctxt = NULL;
186 dispatch_set(SSH2_MSG_USERAUTH_INFO_RESPONSE,
187 &input_userauth_info_response);
189 authctxt->postponed = 1;
194 send_userauth_info_request(Authctxt *authctxt)
196 KbdintAuthctxt *kbdintctxt;
197 char *name, *instr, **prompts;
199 u_int numprompts, *echo_on;
201 kbdintctxt = authctxt->kbdintctxt;
202 if (kbdintctxt->device->query(kbdintctxt->ctxt,
203 &name, &instr, &numprompts, &prompts, &echo_on))
206 packet_start(SSH2_MSG_USERAUTH_INFO_REQUEST);
207 packet_put_cstring(name);
208 packet_put_cstring(instr);
209 packet_put_cstring(""); /* language not used */
210 packet_put_int(numprompts);
211 for (i = 0; i < numprompts; i++) {
212 packet_put_cstring(prompts[i]);
213 packet_put_char(echo_on[i]);
218 for (i = 0; i < numprompts; i++)
228 input_userauth_info_response(int type, int plen, void *ctxt)
230 Authctxt *authctxt = ctxt;
231 KbdintAuthctxt *kbdintctxt;
232 int i, authenticated = 0, res, len;
234 char **response = NULL, *method;
236 if (authctxt == NULL)
237 fatal("input_userauth_info_response: no authctxt");
238 kbdintctxt = authctxt->kbdintctxt;
239 if (kbdintctxt == NULL || kbdintctxt->ctxt == NULL)
240 fatal("input_userauth_info_response: no kbdintctxt");
241 if (kbdintctxt->device == NULL)
242 fatal("input_userauth_info_response: no device");
244 authctxt->postponed = 0; /* reset */
245 nresp = packet_get_int();
247 response = xmalloc(nresp * sizeof(char*));
248 for (i = 0; i < nresp; i++)
249 response[i] = packet_get_string(NULL);
253 if (authctxt->valid) {
254 res = kbdintctxt->device->respond(kbdintctxt->ctxt,
260 for (i = 0; i < nresp; i++) {
261 memset(response[i], 'r', strlen(response[i]));
273 /* Authentication needs further interaction */
274 authctxt->postponed = 1;
275 if (send_userauth_info_request(authctxt) == 0) {
276 authctxt->postponed = 0;
284 len = strlen("keyboard-interactive") + 2 +
285 strlen(kbdintctxt->device->name);
286 method = xmalloc(len);
288 strlcat(method, "keyboard-interactive", len);
289 strlcat(method, "/", len);
290 strlcat(method, kbdintctxt->device->name, len);
292 if (!authctxt->postponed) {
293 /* unregister callback */
294 dispatch_set(SSH2_MSG_USERAUTH_INFO_RESPONSE, NULL);
297 kbdint_free(kbdintctxt);
298 authctxt->kbdintctxt = NULL;
300 /* start next device */
301 /* may set authctxt->postponed */
302 auth2_challenge_start(authctxt);
305 userauth_finish(authctxt, authenticated, method);