2 Unix SMB/CIFS implementation.
3 krb5 set password implementation
4 Copyright (C) Andrew Tridgell 2001
5 Copyright (C) Remus Koos 2001 (remuskoos@yahoo.com)
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 #define DEFAULT_KPASSWD_PORT 464
27 #define KRB5_KPASSWD_VERS_CHANGEPW 1
28 #define KRB5_KPASSWD_VERS_SETPW 0xff80
29 #define KRB5_KPASSWD_ACCESSDENIED 5
30 #define KRB5_KPASSWD_BAD_VERSION 6
32 /* This implements the Kerb password change protocol as specifed in
33 * kerb-chg-password-02.txt
35 static DATA_BLOB encode_krb5_setpw(const char *principal, const char *password)
37 char* princ_part1 = NULL;
38 char* princ_part2 = NULL;
47 princ = strdup(principal);
49 if ((c = strchr(princ, '/')) == NULL) {
59 if ((c = strchr(c, '@')) != NULL) {
65 memset(&req, 0, sizeof(req));
67 asn1_push_tag(&req, ASN1_SEQUENCE(0));
68 asn1_push_tag(&req, ASN1_CONTEXT(0));
69 asn1_write_OctetString(&req, password, strlen(password));
72 asn1_push_tag(&req, ASN1_CONTEXT(1));
73 asn1_push_tag(&req, ASN1_SEQUENCE(0));
75 asn1_push_tag(&req, ASN1_CONTEXT(0));
76 asn1_write_Integer(&req, 1);
79 asn1_push_tag(&req, ASN1_CONTEXT(1));
80 asn1_push_tag(&req, ASN1_SEQUENCE(0));
83 asn1_write_GeneralString(&req, princ_part1);
85 asn1_write_GeneralString(&req, princ_part2);
91 asn1_push_tag(&req, ASN1_CONTEXT(2));
92 asn1_write_GeneralString(&req, realm);
96 ret = data_blob(req.data, req.length);
104 static krb5_error_code build_setpw_request(krb5_context context,
105 krb5_auth_context auth_context,
113 krb5_data encoded_setpw;
114 krb5_replay_data replay;
118 ret = krb5_auth_con_setflags(context,
119 auth_context,KRB5_AUTH_CONTEXT_DO_SEQUENCE);
121 DEBUG(1,("krb5_auth_con_setflags failed (%s)\n",
122 error_message(ret)));
126 setpw = encode_krb5_setpw(princ, passwd);
128 encoded_setpw.data = setpw.data;
129 encoded_setpw.length = setpw.length;
131 ret = krb5_mk_priv(context, auth_context,
132 &encoded_setpw, &cipherpw, &replay);
134 data_blob_free(&setpw); /*from 'encode_krb5_setpw(...)' */
137 DEBUG(1,("krb5_mk_priv failed (%s)\n", error_message(ret)));
141 packet->data = (char *)malloc(ap_req->length + cipherpw.length + 6);
143 /* see the RFC for details */
144 p = ((char *)packet->data) + 2;
145 RSSVAL(p, 0, 0xff80); p += 2;
146 RSSVAL(p, 0, ap_req->length); p += 2;
147 memcpy(p, ap_req->data, ap_req->length); p += ap_req->length;
148 memcpy(p, cipherpw.data, cipherpw.length); p += cipherpw.length;
149 packet->length = PTR_DIFF(p,packet->data);
150 RSSVAL(packet->data, 0, packet->length);
152 free(cipherpw.data); /* from 'krb5_mk_priv(...)' */
157 static krb5_error_code parse_setpw_reply(krb5_context context,
158 krb5_auth_context auth_context,
163 int vnum, ret, res_code;
164 krb5_data cipherresult;
165 krb5_data clearresult;
166 krb5_ap_rep_enc_part *ap_rep_enc;
167 krb5_replay_data replay;
169 if (packet->length < 4) {
170 return KRB5KRB_AP_ERR_MODIFIED;
175 if (((char *)packet->data)[0] == 0x7e || ((char *)packet->data)[0] == 0x5e) {
176 /* it's an error packet. We should parse it ... */
177 DEBUG(1,("Got error packet 0x%x from kpasswd server\n",
178 ((char *)packet->data)[0]));
179 return KRB5KRB_AP_ERR_MODIFIED;
182 if (RSVAL(p, 0) != packet->length) {
183 DEBUG(1,("Bad packet length (%d/%d) from kpasswd server\n",
184 RSVAL(p, 0), packet->length));
185 return KRB5KRB_AP_ERR_MODIFIED;
190 vnum = RSVAL(p, 0); p += 2;
192 if (vnum != KRB5_KPASSWD_VERS_SETPW && vnum != KRB5_KPASSWD_VERS_CHANGEPW) {
193 DEBUG(1,("Bad vnum (%d) from kpasswd server\n", vnum));
194 return KRB5KDC_ERR_BAD_PVNO;
197 ap_rep.length = RSVAL(p, 0); p += 2;
199 if (p + ap_rep.length >= (char *)packet->data + packet->length) {
200 DEBUG(1,("ptr beyond end of packet from kpasswd server\n"));
201 return KRB5KRB_AP_ERR_MODIFIED;
204 if (ap_rep.length == 0) {
205 DEBUG(1,("got unencrypted setpw result?!\n"));
206 return KRB5KRB_AP_ERR_MODIFIED;
213 ret = krb5_rd_rep(context, auth_context, &ap_rep, &ap_rep_enc);
215 DEBUG(1,("failed to rd setpw reply (%s)\n", error_message(ret)));
216 return KRB5KRB_AP_ERR_MODIFIED;
219 krb5_free_ap_rep_enc_part(context, ap_rep_enc);
221 cipherresult.data = p;
222 cipherresult.length = ((char *)packet->data + packet->length) - p;
224 ret = krb5_rd_priv(context, auth_context, &cipherresult, &clearresult,
227 DEBUG(1,("failed to decrypt setpw reply (%s)\n", error_message(ret)));
228 return KRB5KRB_AP_ERR_MODIFIED;
231 if (clearresult.length < 2) {
232 free(clearresult.data);
233 ret = KRB5KRB_AP_ERR_MODIFIED;
234 return KRB5KRB_AP_ERR_MODIFIED;
237 p = clearresult.data;
239 res_code = RSVAL(p, 0);
241 free(clearresult.data);
243 if ((res_code < KRB5_KPASSWD_SUCCESS) ||
244 (res_code >= KRB5_KPASSWD_ACCESSDENIED)) {
245 return KRB5KRB_AP_ERR_MODIFIED;
251 ADS_STATUS krb5_set_password(const char *kdc_host, const char *princ, const char *newpw,
254 krb5_context context;
255 krb5_auth_context auth_context = NULL;
256 krb5_principal principal;
259 krb5_creds creds, *credsp;
261 krb5_data ap_req, chpw_req, chpw_rep;
262 int ret, sock, addr_len;
263 struct sockaddr remote_addr, local_addr;
264 krb5_address local_kaddr, remote_kaddr;
266 ret = krb5_init_context(&context);
268 DEBUG(1,("Failed to init krb5 context (%s)\n", error_message(ret)));
269 return ADS_ERROR_KRB5(ret);
272 if (time_offset != 0) {
273 krb5_set_real_time(context, time(NULL) + time_offset, 0);
276 ret = krb5_cc_default(context, &ccache);
278 krb5_free_context(context);
279 DEBUG(1,("Failed to get default creds (%s)\n", error_message(ret)));
280 return ADS_ERROR_KRB5(ret);
285 realm = strchr(princ, '@');
288 asprintf(&princ_name, "kadmin/changepw@%s", realm);
289 ret = krb5_parse_name(context, princ_name, &creds.server);
291 krb5_free_context(context);
292 DEBUG(1,("Failed to parse kadmin/changepw (%s)\n", error_message(ret)));
293 return ADS_ERROR_KRB5(ret);
297 /* parse the principal we got as a function argument */
298 ret = krb5_parse_name(context, princ, &principal);
300 krb5_free_context(context);
301 DEBUG(1,("Failed to parse %s (%s)\n", princ_name, error_message(ret)));
302 return ADS_ERROR_KRB5(ret);
305 krb5_princ_set_realm(context, creds.server,
306 krb5_princ_realm(context, principal));
308 ret = krb5_cc_get_principal(context, ccache, &creds.client);
310 krb5_free_principal(context, principal);
311 krb5_free_context(context);
312 DEBUG(1,("Failed to get principal from ccache (%s)\n",
313 error_message(ret)));
314 return ADS_ERROR_KRB5(ret);
317 ret = krb5_get_credentials(context, 0, ccache, &creds, &credsp);
319 krb5_free_principal(context, creds.client);
320 krb5_free_principal(context, principal);
321 krb5_free_context(context);
322 DEBUG(1,("krb5_get_credentials failed (%s)\n", error_message(ret)));
323 return ADS_ERROR_KRB5(ret);
326 /* we might have to call krb5_free_creds(...) from now on ... */
327 ret = krb5_mk_req_extended(context, &auth_context, AP_OPTS_USE_SUBKEY,
328 NULL, credsp, &ap_req);
330 krb5_free_creds(context, credsp);
331 krb5_free_principal(context, creds.client);
332 krb5_free_principal(context, principal);
333 krb5_free_context(context);
334 DEBUG(1,("krb5_mk_req_extended failed (%s)\n", error_message(ret)));
335 return ADS_ERROR_KRB5(ret);
338 sock = open_udp_socket(kdc_host, DEFAULT_KPASSWD_PORT);
342 krb5_free_creds(context, credsp);
343 krb5_free_principal(context, creds.client);
344 krb5_free_principal(context, principal);
345 krb5_free_context(context);
346 DEBUG(1,("failed to open kpasswd socket to %s (%s)\n",
347 kdc_host, strerror(errno)));
348 return ADS_ERROR_SYSTEM(rc);
351 addr_len = sizeof(remote_addr);
352 getpeername(sock, &remote_addr, &addr_len);
353 addr_len = sizeof(local_addr);
354 getsockname(sock, &local_addr, &addr_len);
356 setup_kaddr(&remote_kaddr, &remote_addr);
357 setup_kaddr(&local_kaddr, &local_addr);
359 ret = krb5_auth_con_setaddrs(context, auth_context, &local_kaddr, NULL);
363 krb5_free_creds(context, credsp);
364 krb5_free_principal(context, creds.client);
365 krb5_free_principal(context, principal);
366 krb5_free_context(context);
367 DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n", error_message(ret)));
368 return ADS_ERROR_KRB5(ret);
371 ret = build_setpw_request(context, auth_context, &ap_req,
372 princ, newpw, &chpw_req);
376 krb5_free_creds(context, credsp);
377 krb5_free_principal(context, creds.client);
378 krb5_free_principal(context, principal);
379 krb5_free_context(context);
380 DEBUG(1,("build_setpw_request failed (%s)\n", error_message(ret)));
381 return ADS_ERROR_KRB5(ret);
384 if (write(sock, chpw_req.data, chpw_req.length) != chpw_req.length) {
388 krb5_free_creds(context, credsp);
389 krb5_free_principal(context, creds.client);
390 krb5_free_principal(context, principal);
391 krb5_free_context(context);
392 DEBUG(1,("send of chpw failed (%s)\n", strerror(errno)));
393 return ADS_ERROR_SYSTEM(errno);
398 chpw_rep.length = 1500;
399 chpw_rep.data = (char *) malloc(chpw_rep.length);
401 ret = read(sock, chpw_rep.data, chpw_rep.length);
406 krb5_free_creds(context, credsp);
407 krb5_free_principal(context, creds.client);
408 krb5_free_principal(context, principal);
409 krb5_free_context(context);
410 DEBUG(1,("recv of chpw reply failed (%s)\n", strerror(errno)));
411 return ADS_ERROR_SYSTEM(errno);
415 chpw_rep.length = ret;
417 ret = krb5_auth_con_setaddrs(context, auth_context, NULL,&remote_kaddr);
421 krb5_free_creds(context, credsp);
422 krb5_free_principal(context, creds.client);
423 krb5_free_principal(context, principal);
424 krb5_free_context(context);
425 DEBUG(1,("krb5_auth_con_setaddrs on reply failed (%s)\n",
426 error_message(ret)));
427 return ADS_ERROR_KRB5(ret);
430 ret = parse_setpw_reply(context, auth_context, &chpw_rep);
435 krb5_free_creds(context, credsp);
436 krb5_free_principal(context, creds.client);
437 krb5_free_principal(context, principal);
438 krb5_free_context(context);
439 DEBUG(1,("parse_setpw_reply failed (%s)\n",
440 error_message(ret)));
441 return ADS_ERROR_KRB5(ret);
445 krb5_free_creds(context, credsp);
446 krb5_free_principal(context, creds.client);
447 krb5_free_principal(context, principal);
448 krb5_free_context(context);
454 ADS_STATUS kerberos_set_password(const char *kpasswd_server,
455 const char *auth_principal, const char *auth_password,
456 const char *target_principal, const char *new_password,
461 if ((ret = kerberos_kinit_password(auth_principal, auth_password, time_offset))) {
462 DEBUG(1,("Failed kinit for principal %s (%s)\n", auth_principal, error_message(ret)));
463 return ADS_ERROR_KRB5(ret);
466 return krb5_set_password(kpasswd_server, target_principal, new_password, time_offset);
471 * Set the machine account password
472 * @param ads connection to ads server
473 * @param hostname machine whose password is being set
474 * @param password new password
475 * @return status of password change
477 ADS_STATUS ads_set_machine_password(ADS_STRUCT *ads,
478 const char *hostname,
479 const char *password)
482 char *host = strdup(hostname);
488 we need to use the '$' form of the name here, as otherwise the
489 server might end up setting the password for a user instead
491 asprintf(&principal, "%s$@%s", host, ads->auth.realm);
493 status = krb5_set_password(ads->auth.kdc_server, principal, password, ads->auth.time_offset);