source4/kdc/kpasswd-service-heimdal.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Samba kpasswd implementation
   5
   6    Copyright (c) 2016      Andreas Schneider <asn@samba.org>
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "smbd/service_task.h"
  24 #include "param/param.h"
  25 #include "auth/auth.h"
  26 #include "auth/gensec/gensec.h"
  27 #include "kdc/kdc-server.h"
  28 #include "kdc/kpasswd_glue.h"
  29 #include "kdc/kpasswd-service.h"
  30 #include "kdc/kpasswd-helper.h"
  31
  32 static krb5_error_code kpasswd_change_password(struct kdc_server *kdc,
  33                                                TALLOC_CTX *mem_ctx,
  34                                                struct auth_session_info *session_info,
  35                                                DATA_BLOB *password,
  36                                                DATA_BLOB *kpasswd_reply,
  37                                                const char **error_string)
  38 {
  39         NTSTATUS status;
  40         NTSTATUS result = NT_STATUS_UNSUCCESSFUL;
  41         enum samPwdChangeReason reject_reason;
  42         const char *reject_string = NULL;
  43         struct samr_DomInfo1 *dominfo;
  44         bool ok;
  45
  46         status = samdb_kpasswd_change_password(mem_ctx,
  47                                                kdc->task->lp_ctx,
  48                                                kdc->task->event_ctx,
  49                                                kdc->samdb,
  50                                                session_info,
  51                                                password,
  52                                                &reject_reason,
  53                                                &dominfo,
  54                                                &reject_string,
  55                                                &result);
  56         if (!NT_STATUS_IS_OK(status)) {
  57                 ok = kpasswd_make_error_reply(mem_ctx,
  58                                               KRB5_KPASSWD_ACCESSDENIED,
  59                                               reject_string,
  60                                               kpasswd_reply);
  61                 if (!ok) {
  62                         *error_string = "Failed to create reply";
  63                         return KRB5_KPASSWD_HARDERROR;
  64                 }
  65                 /* We want to send an an authenticated packet. */
  66                 return 0;
  67         }
  68
  69         ok = kpasswd_make_pwchange_reply(mem_ctx,
  70                                          result,
  71                                          reject_reason,
  72                                          dominfo,
  73                                          kpasswd_reply);
  74         if (!ok) {
  75                 *error_string = "Failed to create reply";
  76                 return KRB5_KPASSWD_HARDERROR;
  77         }
  78
  79         return 0;
  80 }
  81
  82 static krb5_error_code kpasswd_set_password(struct kdc_server *kdc,
  83                                             TALLOC_CTX *mem_ctx,
  84                                             struct auth_session_info *session_info,
  85                                             DATA_BLOB *decoded_data,
  86                                             DATA_BLOB *kpasswd_reply,
  87                                             const char **error_string)
  88 {
  89         krb5_context context = kdc->smb_krb5_context->krb5_context;
  90         krb5_error_code code;
  91         krb5_principal target_principal;
  92         ChangePasswdDataMS chpw = {};
  93         size_t chpw_len = 0;
  94         DATA_BLOB password = data_blob_null;
  95         enum samPwdChangeReason reject_reason = SAM_PWD_CHANGE_NO_ERROR;
  96         struct samr_DomInfo1 *dominfo = NULL;
  97         char *target_principal_string = NULL;
  98         bool is_service_principal = false;
  99         NTSTATUS status;
 100         bool ok;
 101
 102         code = decode_ChangePasswdDataMS(decoded_data->data,
 103                                          decoded_data->length,
 104                                          &chpw,
 105                                          &chpw_len);
 106         if (code != 0) {
 107                 DBG_WARNING("decode_ChangePasswdDataMS failed\n");
 108                 ok = kpasswd_make_error_reply(mem_ctx,
 109                                               KRB5_KPASSWD_MALFORMED,
 110                                               "Failed to decode packet",
 111                                               kpasswd_reply);
 112                 if (!ok) {
 113                         *error_string = "Failed to create reply";
 114                         return KRB5_KPASSWD_HARDERROR;
 115                 }
 116                 return 0;
 117         }
 118
 119         ok = convert_string_talloc_handle(mem_ctx,
 120                                           lpcfg_iconv_handle(kdc->task->lp_ctx),
 121                                           CH_UTF8,
 122                                           CH_UTF16,
 123                                           (const char *)chpw.newpasswd.data,
 124                                           chpw.newpasswd.length,
 125                                           (void **)&password.data,
 126                                           &password.length);
 127         if (!ok) {
 128                 free_ChangePasswdDataMS(&chpw);
 129                 DBG_WARNING("String conversion failed\n");
 130                 *error_string = "String conversion failed";
 131                 return KRB5_KPASSWD_HARDERROR;
 132         }
 133
 134         if ((chpw.targname != NULL && chpw.targrealm == NULL) ||
 135             (chpw.targname == NULL && chpw.targrealm != NULL)) {
 136                 free_ChangePasswdDataMS(&chpw);
 137                 ok = kpasswd_make_error_reply(mem_ctx,
 138                                               KRB5_KPASSWD_MALFORMED,
 139                                               "Realm and principal must be "
 140                                               "both present, or neither present",
 141                                               kpasswd_reply);
 142                 if (!ok) {
 143                         *error_string = "Failed to create reply";
 144                         return KRB5_KPASSWD_HARDERROR;
 145                 }
 146                 return 0;
 147         }
 148
 149         if (chpw.targname != NULL && chpw.targrealm != NULL) {
 150                 code = krb5_build_principal_ext(context,
 151                                                &target_principal,
 152                                                strlen(*chpw.targrealm),
 153                                                *chpw.targrealm,
 154                                                0);
 155                 if (code != 0) {
 156                         free_ChangePasswdDataMS(&chpw);
 157                         return kpasswd_make_error_reply(mem_ctx,
 158                                                         KRB5_KPASSWD_MALFORMED,
 159                                                         "Failed to parse principal",
 160                                                         kpasswd_reply);
 161                 }
 162                 code = copy_PrincipalName(chpw.targname,
 163                                           &target_principal->name);
 164                 if (code != 0) {
 165                         free_ChangePasswdDataMS(&chpw);
 166                         krb5_free_principal(context, target_principal);
 167                         return kpasswd_make_error_reply(mem_ctx,
 168                                                         KRB5_KPASSWD_MALFORMED,
 169                                                         "Failed to parse principal",
 170                                                         kpasswd_reply);
 171                 }
 172         } else {
 173                 free_ChangePasswdDataMS(&chpw);
 174                 return kpasswd_change_password(kdc,
 175                                                mem_ctx,
 176                                                session_info,
 177                                                &password,
 178                                                kpasswd_reply,
 179                                                error_string);
 180         }
 181         free_ChangePasswdDataMS(&chpw);
 182
 183         if (target_principal->name.name_string.len >= 2) {
 184                 is_service_principal = true;
 185
 186                 code = krb5_unparse_name_short(context,
 187                                                target_principal,
 188                                                &target_principal_string);
 189         } else {
 190                 code = krb5_unparse_name(context,
 191                                          target_principal,
 192                                          &target_principal_string);
 193         }
 194         krb5_free_principal(context, target_principal);
 195         if (code != 0) {
 196                 ok = kpasswd_make_error_reply(mem_ctx,
 197                                               KRB5_KPASSWD_MALFORMED,
 198                                               "Failed to parse principal",
 199                                               kpasswd_reply);
 200                 if (!ok) {
 201                         *error_string = "Failed to create reply";
 202                         return KRB5_KPASSWD_HARDERROR;
 203                 }
 204         }
 205
 206         status = kpasswd_samdb_set_password(mem_ctx,
 207                                             kdc->task->event_ctx,
 208                                             kdc->task->lp_ctx,
 209                                             session_info,
 210                                             is_service_principal,
 211                                             target_principal_string,
 212                                             &password,
 213                                             &reject_reason,
 214                                             &dominfo);
 215         if (!NT_STATUS_IS_OK(status)) {
 216                 DBG_ERR("kpasswd_samdb_set_password failed - %s\n",
 217                         nt_errstr(status));
 218         }
 219
 220         ok = kpasswd_make_pwchange_reply(mem_ctx,
 221                                          status,
 222                                          reject_reason,
 223                                          dominfo,
 224                                          kpasswd_reply);
 225         if (!ok) {
 226                 *error_string = "Failed to create reply";
 227                 return KRB5_KPASSWD_HARDERROR;
 228         }
 229
 230         return 0;
 231 }
 232
 233 krb5_error_code kpasswd_handle_request(struct kdc_server *kdc,
 234                                        TALLOC_CTX *mem_ctx,
 235                                        struct gensec_security *gensec_security,
 236                                        uint16_t verno,
 237                                        DATA_BLOB *decoded_data,
 238                                        DATA_BLOB *kpasswd_reply,
 239                                        const char **error_string)
 240 {
 241         struct auth_session_info *session_info;
 242         NTSTATUS status;
 243
 244         status = gensec_session_info(gensec_security,
 245                                      mem_ctx,
 246                                      &session_info);
 247         if (!NT_STATUS_IS_OK(status)) {
 248                 *error_string = talloc_asprintf(mem_ctx,
 249                                                 "gensec_session_info failed - %s",
 250                                                 nt_errstr(status));
 251                 return KRB5_KPASSWD_HARDERROR;
 252         }
 253
 254         switch(verno) {
 255         case KRB5_KPASSWD_VERS_CHANGEPW: {
 256                 DATA_BLOB password = data_blob_null;
 257                 bool ok;
 258
 259                 ok = convert_string_talloc_handle(mem_ctx,
 260                                                   lpcfg_iconv_handle(kdc->task->lp_ctx),
 261                                                   CH_UTF8,
 262                                                   CH_UTF16,
 263                                                   (const char *)decoded_data->data,
 264                                                   decoded_data->length,
 265                                                   (void **)&password.data,
 266                                                   &password.length);
 267                 if (!ok) {
 268                         *error_string = "String conversion failed!";
 269                         DBG_WARNING("%s\n", *error_string);
 270                         return KRB5_KPASSWD_HARDERROR;
 271                 }
 272
 273                 return kpasswd_change_password(kdc,
 274                                                mem_ctx,
 275                                                session_info,
 276                                                &password,
 277                                                kpasswd_reply,
 278                                                error_string);
 279         }
 280         case KRB5_KPASSWD_VERS_SETPW: {
 281                 return kpasswd_set_password(kdc,
 282                                             mem_ctx,
 283                                             session_info,
 284                                             decoded_data,
 285                                             kpasswd_reply,
 286                                             error_string);
 287         }
 288         default:
 289                 *error_string = talloc_asprintf(mem_ctx,
 290                                                 "Protocol version %u not supported",
 291                                                 verno);
 292                 return KRB5_KPASSWD_BAD_VERSION;
 293         }
 294
 295         return 0;
 296 }