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-rw-r--r--source3/libads/krb5_setpw.c468
1 files changed, 468 insertions, 0 deletions
diff --git a/source3/libads/krb5_setpw.c b/source3/libads/krb5_setpw.c
new file mode 100644
index 0000000000..ec79a8658f
--- /dev/null
+++ b/source3/libads/krb5_setpw.c
@@ -0,0 +1,468 @@
+/*
+ Unix SMB/CIFS implementation.
+ krb5 set password implementation
+ Copyright (C) Andrew Tridgell 2001
+ Copyright (C) Remus Koos 2001 (remuskoos@yahoo.com)
+
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+#ifdef HAVE_KRB5
+
+#define DEFAULT_KPASSWD_PORT 464
+#define KRB5_KPASSWD_VERS_CHANGEPW 1
+#define KRB5_KPASSWD_VERS_SETPW 0xff80
+#define KRB5_KPASSWD_ACCESSDENIED 5
+#define KRB5_KPASSWD_BAD_VERSION 6
+
+/* This implements the Kerb password change protocol as specifed in
+ * kerb-chg-password-02.txt
+ */
+static DATA_BLOB encode_krb5_setpw(const char *principal, const char *password)
+{
+ char* princ_part1 = NULL;
+ char* princ_part2 = NULL;
+ char* realm = NULL;
+ char* c;
+ char* princ;
+
+ ASN1_DATA req;
+ DATA_BLOB ret;
+
+
+ princ = strdup(principal);
+
+ if ((c = strchr(princ, '/')) == NULL) {
+ c = princ;
+ } else {
+ *c = '\0';
+ c++;
+ princ_part1 = princ;
+ }
+
+ princ_part2 = c;
+
+ if ((c = strchr(c, '@')) != NULL) {
+ *c = '\0';
+ c++;
+ realm = c;
+ }
+
+ memset(&req, 0, sizeof(req));
+
+ asn1_push_tag(&req, ASN1_SEQUENCE(0));
+ asn1_push_tag(&req, ASN1_CONTEXT(0));
+ asn1_write_OctetString(&req, password, strlen(password));
+ asn1_pop_tag(&req);
+
+ asn1_push_tag(&req, ASN1_CONTEXT(1));
+ asn1_push_tag(&req, ASN1_SEQUENCE(0));
+
+ asn1_push_tag(&req, ASN1_CONTEXT(0));
+ asn1_write_Integer(&req, 1);
+ asn1_pop_tag(&req);
+
+ asn1_push_tag(&req, ASN1_CONTEXT(1));
+ asn1_push_tag(&req, ASN1_SEQUENCE(0));
+
+ if (princ_part1)
+ asn1_write_GeneralString(&req, princ_part1);
+
+ asn1_write_GeneralString(&req, princ_part2);
+ asn1_pop_tag(&req);
+ asn1_pop_tag(&req);
+ asn1_pop_tag(&req);
+ asn1_pop_tag(&req);
+
+ asn1_push_tag(&req, ASN1_CONTEXT(2));
+ asn1_write_GeneralString(&req, realm);
+ asn1_pop_tag(&req);
+ asn1_pop_tag(&req);
+
+ ret = data_blob(req.data, req.length);
+ asn1_free(&req);
+
+ free(princ);
+
+ return ret;
+}
+
+static krb5_error_code build_setpw_request(krb5_context context,
+ krb5_auth_context auth_context,
+ krb5_data *ap_req,
+ const char *princ,
+ const char *passwd,
+ krb5_data *packet)
+{
+ krb5_error_code ret;
+ krb5_data cipherpw;
+ krb5_data encoded_setpw;
+ krb5_replay_data replay;
+ char *p;
+ DATA_BLOB setpw;
+
+ ret = krb5_auth_con_setflags(context,
+ auth_context,KRB5_AUTH_CONTEXT_DO_SEQUENCE);
+ if (ret) {
+ DEBUG(1,("krb5_auth_con_setflags failed (%s)\n",
+ error_message(ret)));
+ return ret;
+ }
+
+ setpw = encode_krb5_setpw(princ, passwd);
+
+ encoded_setpw.data = setpw.data;
+ encoded_setpw.length = setpw.length;
+
+ ret = krb5_mk_priv(context, auth_context,
+ &encoded_setpw, &cipherpw, &replay);
+
+ data_blob_free(&setpw); /*from 'encode_krb5_setpw(...)' */
+
+ if (ret) {
+ DEBUG(1,("krb5_mk_priv failed (%s)\n", error_message(ret)));
+ return ret;
+ }
+
+ packet->data = (char *)malloc(ap_req->length + cipherpw.length + 6);
+
+ /* see the RFC for details */
+ p = packet->data + 2;
+ RSSVAL(p, 0, 0xff80); p += 2;
+ RSSVAL(p, 0, ap_req->length); p += 2;
+ memcpy(p, ap_req->data, ap_req->length); p += ap_req->length;
+ memcpy(p, cipherpw.data, cipherpw.length); p += cipherpw.length;
+ packet->length = PTR_DIFF(p,packet->data);
+ RSSVAL(packet->data, 0, packet->length);
+
+ free(cipherpw.data); /* from 'krb5_mk_priv(...)' */
+
+ return 0;
+}
+
+static krb5_error_code parse_setpw_reply(krb5_context context,
+ krb5_auth_context auth_context,
+ krb5_data *packet)
+{
+ krb5_data ap_rep;
+ char *p;
+ int vnum, ret, res_code;
+ krb5_data cipherresult;
+ krb5_data clearresult;
+ krb5_ap_rep_enc_part *ap_rep_enc;
+ krb5_replay_data replay;
+
+ if (packet->length < 4) {
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ p = packet->data;
+
+ if (packet->data[0] == 0x7e || packet->data[0] == 0x5e) {
+ /* it's an error packet. We should parse it ... */
+ DEBUG(1,("Got error packet 0x%x from kpasswd server\n",
+ packet->data[0]));
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ if (RSVAL(p, 0) != packet->length) {
+ DEBUG(1,("Bad packet length (%d/%d) from kpasswd server\n",
+ RSVAL(p, 0), packet->length));
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ p += 2;
+
+ vnum = RSVAL(p, 0); p += 2;
+
+ if (vnum != KRB5_KPASSWD_VERS_SETPW && vnum != KRB5_KPASSWD_VERS_CHANGEPW) {
+ DEBUG(1,("Bad vnum (%d) from kpasswd server\n", vnum));
+ return KRB5KDC_ERR_BAD_PVNO;
+ }
+
+ ap_rep.length = RSVAL(p, 0); p += 2;
+
+ if (p + ap_rep.length >= packet->data + packet->length) {
+ DEBUG(1,("ptr beyond end of packet from kpasswd server\n"));
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ if (ap_rep.length == 0) {
+ DEBUG(1,("got unencrypted setpw result?!\n"));
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ /* verify ap_rep */
+ ap_rep.data = p;
+ p += ap_rep.length;
+
+ ret = krb5_rd_rep(context, auth_context, &ap_rep, &ap_rep_enc);
+ if (ret) {
+ DEBUG(1,("failed to rd setpw reply (%s)\n", error_message(ret)));
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ krb5_free_ap_rep_enc_part(context, ap_rep_enc);
+
+ cipherresult.data = p;
+ cipherresult.length = (packet->data + packet->length) - p;
+
+ ret = krb5_rd_priv(context, auth_context, &cipherresult, &clearresult,
+ &replay);
+ if (ret) {
+ DEBUG(1,("failed to decrypt setpw reply (%s)\n", error_message(ret)));
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ if (clearresult.length < 2) {
+ free(clearresult.data);
+ ret = KRB5KRB_AP_ERR_MODIFIED;
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ p = clearresult.data;
+
+ res_code = RSVAL(p, 0);
+
+ free(clearresult.data);
+
+ if ((res_code < KRB5_KPASSWD_SUCCESS) ||
+ (res_code >= KRB5_KPASSWD_ACCESSDENIED)) {
+ return KRB5KRB_AP_ERR_MODIFIED;
+ }
+
+ return 0;
+}
+
+ADS_STATUS krb5_set_password(const char *kdc_host, const char *princ, const char *newpw)
+{
+ krb5_context context;
+ krb5_auth_context auth_context = NULL;
+ krb5_principal principal;
+ char *princ_name;
+ char *realm;
+ krb5_creds creds, *credsp;
+ krb5_ccache ccache;
+ krb5_data ap_req, chpw_req, chpw_rep;
+ int ret, sock, addr_len;
+ struct sockaddr remote_addr, local_addr;
+ krb5_address local_kaddr, remote_kaddr;
+
+ ret = krb5_init_context(&context);
+ if (ret) {
+ DEBUG(1,("Failed to init krb5 context (%s)\n", error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ ret = krb5_cc_default(context, &ccache);
+ if (ret) {
+ krb5_free_context(context);
+ DEBUG(1,("Failed to get default creds (%s)\n", error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ ZERO_STRUCT(creds);
+
+ realm = strchr(princ, '@');
+ realm++;
+
+ asprintf(&princ_name, "kadmin/changepw@%s", realm);
+ ret = krb5_parse_name(context, princ_name, &creds.server);
+ if (ret) {
+ krb5_free_context(context);
+ DEBUG(1,("Failed to parse kadmin/changepw (%s)\n", error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+ free(princ_name);
+
+ /* parse the principal we got as a function argument */
+ ret = krb5_parse_name(context, princ, &principal);
+ if (ret) {
+ krb5_free_context(context);
+ DEBUG(1,("Failed to parse %s (%s)\n", princ_name, error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ krb5_princ_set_realm(context, creds.server,
+ krb5_princ_realm(context, principal));
+
+ ret = krb5_cc_get_principal(context, ccache, &creds.client);
+ if (ret) {
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("Failed to get principal from ccache (%s)\n",
+ error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ ret = krb5_get_credentials(context, 0, ccache, &creds, &credsp);
+ if (ret) {
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("krb5_get_credentials failed (%s)\n", error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ /* we might have to call krb5_free_creds(...) from now on ... */
+ ret = krb5_mk_req_extended(context, &auth_context, AP_OPTS_USE_SUBKEY,
+ NULL, credsp, &ap_req);
+ if (ret) {
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("krb5_mk_req_extended failed (%s)\n", error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ sock = open_udp_socket(kdc_host, DEFAULT_KPASSWD_PORT);
+ if (sock == -1) {
+ int rc = errno;
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("failed to open kpasswd socket to %s (%s)\n",
+ kdc_host, strerror(errno)));
+ return ADS_ERROR_SYSTEM(rc);
+ }
+
+ addr_len = sizeof(remote_addr);
+ getpeername(sock, &remote_addr, &addr_len);
+ addr_len = sizeof(local_addr);
+ getsockname(sock, &local_addr, &addr_len);
+
+ remote_kaddr.addrtype = ADDRTYPE_INET;
+ remote_kaddr.length = sizeof(((struct sockaddr_in *)&remote_addr)->sin_addr);
+ remote_kaddr.contents = (char *)&(((struct sockaddr_in *)&remote_addr)->sin_addr);
+ local_kaddr.addrtype = ADDRTYPE_INET;
+ local_kaddr.length = sizeof(((struct sockaddr_in *)&local_addr)->sin_addr);
+ local_kaddr.contents = (char *)&(((struct sockaddr_in *)&local_addr)->sin_addr);
+
+ ret = krb5_auth_con_setaddrs(context, auth_context, &local_kaddr, NULL);
+ if (ret) {
+ close(sock);
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n", error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ ret = build_setpw_request(context, auth_context, &ap_req,
+ princ, newpw, &chpw_req);
+ if (ret) {
+ close(sock);
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("build_setpw_request failed (%s)\n", error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ if (write(sock, chpw_req.data, chpw_req.length) != chpw_req.length) {
+ close(sock);
+ free(chpw_req.data);
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("send of chpw failed (%s)\n", strerror(errno)));
+ return ADS_ERROR_SYSTEM(errno);
+ }
+
+ free(chpw_req.data);
+
+ chpw_rep.length = 1500;
+ chpw_rep.data = (char *) malloc(chpw_rep.length);
+
+ ret = read(sock, chpw_rep.data, chpw_rep.length);
+ if (ret < 0) {
+ close(sock);
+ free(chpw_rep.data);
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("recv of chpw reply failed (%s)\n", strerror(errno)));
+ return ADS_ERROR_SYSTEM(errno);
+ }
+
+ close(sock);
+ chpw_rep.length = ret;
+
+ ret = krb5_auth_con_setaddrs(context, auth_context, NULL,&remote_kaddr);
+ if (ret) {
+ free(chpw_rep.data);
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("krb5_auth_con_setaddrs on reply failed (%s)\n",
+ error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ ret = parse_setpw_reply(context, auth_context, &chpw_rep);
+ free(chpw_rep.data);
+
+ if (ret) {
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+ DEBUG(1,("parse_setpw_reply failed (%s)\n",
+ error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ free(ap_req.data);
+ krb5_free_creds(context, credsp);
+ krb5_free_principal(context, creds.client);
+ krb5_free_principal(context, principal);
+ krb5_free_context(context);
+
+ return ADS_SUCCESS;
+}
+
+
+ADS_STATUS kerberos_set_password(const char *kpasswd_server,
+ const char *auth_principal, const char *auth_password,
+ const char *target_principal, const char *new_password)
+{
+ int ret;
+
+ if ((ret = kerberos_kinit_password(auth_principal, auth_password))) {
+ DEBUG(1,("Failed kinit for principal %s (%s)\n", auth_principal, error_message(ret)));
+ return ADS_ERROR_KRB5(ret);
+ }
+
+ return krb5_set_password(kpasswd_server, target_principal, new_password);
+}
+
+
+#endif