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 "samba/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                                                session_info,
  50                                                password,
  51                                                &reject_reason,
  52                                                &dominfo,
  53                                                &reject_string,
  54                                                &result);
  55         if (!NT_STATUS_IS_OK(status)) {
  56                 ok = kpasswd_make_error_reply(mem_ctx,
  57                                               KRB5_KPASSWD_ACCESSDENIED,
  58                                               reject_string,
  59                                               kpasswd_reply);
  60                 if (!ok) {
  61                         *error_string = "Failed to create reply";
  62                         return KRB5_KPASSWD_HARDERROR;
  63                 }
  64                 /* We want to send an an authenticated packet. */
  65                 return 0;
  66         }
  67
  68         ok = kpasswd_make_pwchange_reply(mem_ctx,
  69                                          result,
  70                                          reject_reason,
  71                                          dominfo,
  72                                          kpasswd_reply);
  73         if (!ok) {
  74                 *error_string = "Failed to create reply";
  75                 return KRB5_KPASSWD_HARDERROR;
  76         }
  77
  78         return 0;
  79 }
  80
  81 static krb5_error_code kpasswd_set_password(struct kdc_server *kdc,
  82                                             TALLOC_CTX *mem_ctx,
  83                                             struct auth_session_info *session_info,
  84                                             DATA_BLOB *decoded_data,
  85                                             DATA_BLOB *kpasswd_reply,
  86                                             const char **error_string)
  87 {
  88         krb5_context context = kdc->smb_krb5_context->krb5_context;
  89         krb5_error_code code;
  90         krb5_principal target_principal;
  91         ChangePasswdDataMS chpw = {};
  92         size_t chpw_len = 0;
  93         DATA_BLOB password = data_blob_null;
  94         enum samPwdChangeReason reject_reason = SAM_PWD_CHANGE_NO_ERROR;
  95         struct samr_DomInfo1 *dominfo = NULL;
  96         char *target_principal_string = NULL;
  97         bool is_service_principal = false;
  98         NTSTATUS status;
  99         bool ok;
 100
 101         code = decode_ChangePasswdDataMS(decoded_data->data,
 102                                          decoded_data->length,
 103                                          &chpw,
 104                                          &chpw_len);
 105         if (code != 0) {
 106                 DBG_WARNING("decode_ChangePasswdDataMS failed\n");
 107                 ok = kpasswd_make_error_reply(mem_ctx,
 108                                               KRB5_KPASSWD_MALFORMED,
 109                                               "Failed to decode packet",
 110                                               kpasswd_reply);
 111                 if (!ok) {
 112                         *error_string = "Failed to create reply";
 113                         return KRB5_KPASSWD_HARDERROR;
 114                 }
 115                 return 0;
 116         }
 117
 118         ok = convert_string_talloc_handle(mem_ctx,
 119                                           lpcfg_iconv_handle(kdc->task->lp_ctx),
 120                                           CH_UTF8,
 121                                           CH_UTF16,
 122                                           (const char *)chpw.newpasswd.data,
 123                                           chpw.newpasswd.length,
 124                                           (void **)&password.data,
 125                                           &password.length);
 126         if (!ok) {
 127                 free_ChangePasswdDataMS(&chpw);
 128                 DBG_WARNING("String conversion failed\n");
 129                 *error_string = "String conversion failed";
 130                 return KRB5_KPASSWD_HARDERROR;
 131         }
 132
 133         if ((chpw.targname != NULL && chpw.targrealm == NULL) ||
 134             (chpw.targname == NULL && chpw.targrealm != NULL)) {
 135                 free_ChangePasswdDataMS(&chpw);
 136                 ok = kpasswd_make_error_reply(mem_ctx,
 137                                               KRB5_KPASSWD_MALFORMED,
 138                                               "Realm and principal must be "
 139                                               "both present, or neither present",
 140                                               kpasswd_reply);
 141                 if (!ok) {
 142                         *error_string = "Failed to create reply";
 143                         return KRB5_KPASSWD_HARDERROR;
 144                 }
 145                 return 0;
 146         }
 147
 148         if (chpw.targname != NULL && chpw.targrealm != NULL) {
 149                 code = krb5_build_principal_ext(context,
 150                                                &target_principal,
 151                                                strlen(*chpw.targrealm),
 152                                                *chpw.targrealm,
 153                                                0);
 154                 if (code != 0) {
 155                         free_ChangePasswdDataMS(&chpw);
 156                         return kpasswd_make_error_reply(mem_ctx,
 157                                                         KRB5_KPASSWD_MALFORMED,
 158                                                         "Failed to parse principal",
 159                                                         kpasswd_reply);
 160                 }
 161                 code = copy_PrincipalName(chpw.targname,
 162                                           &target_principal->name);
 163                 if (code != 0) {
 164                         free_ChangePasswdDataMS(&chpw);
 165                         krb5_free_principal(context, target_principal);
 166                         return kpasswd_make_error_reply(mem_ctx,
 167                                                         KRB5_KPASSWD_MALFORMED,
 168                                                         "Failed to parse principal",
 169                                                         kpasswd_reply);
 170                 }
 171         } else {
 172                 free_ChangePasswdDataMS(&chpw);
 173                 return kpasswd_change_password(kdc,
 174                                                mem_ctx,
 175                                                session_info,
 176                                                &password,
 177                                                kpasswd_reply,
 178                                                error_string);
 179         }
 180         free_ChangePasswdDataMS(&chpw);
 181
 182         if (target_principal->name.name_string.len >= 2) {
 183                 is_service_principal = true;
 184
 185                 code = krb5_unparse_name_short(context,
 186                                                target_principal,
 187                                                &target_principal_string);
 188         } else {
 189                 code = krb5_unparse_name(context,
 190                                          target_principal,
 191                                          &target_principal_string);
 192         }
 193         krb5_free_principal(context, target_principal);
 194         if (code != 0) {
 195                 ok = kpasswd_make_error_reply(mem_ctx,
 196                                               KRB5_KPASSWD_MALFORMED,
 197                                               "Failed to parse principal",
 198                                               kpasswd_reply);
 199                 if (!ok) {
 200                         *error_string = "Failed to create reply";
 201                         return KRB5_KPASSWD_HARDERROR;
 202                 }
 203         }
 204
 205         status = kpasswd_samdb_set_password(mem_ctx,
 206                                             kdc->task->event_ctx,
 207                                             kdc->task->lp_ctx,
 208                                             session_info,
 209                                             is_service_principal,
 210                                             target_principal_string,
 211                                             &password,
 212                                             &reject_reason,
 213                                             &dominfo);
 214         if (!NT_STATUS_IS_OK(status)) {
 215                 DBG_ERR("kpasswd_samdb_set_password failed - %s\n",
 216                         nt_errstr(status));
 217         }
 218
 219         ok = kpasswd_make_pwchange_reply(mem_ctx,
 220                                          status,
 221                                          reject_reason,
 222                                          dominfo,
 223                                          kpasswd_reply);
 224         if (!ok) {
 225                 *error_string = "Failed to create reply";
 226                 return KRB5_KPASSWD_HARDERROR;
 227         }
 228
 229         return 0;
 230 }
 231
 232 krb5_error_code kpasswd_handle_request(struct kdc_server *kdc,
 233                                        TALLOC_CTX *mem_ctx,
 234                                        struct gensec_security *gensec_security,
 235                                        uint16_t verno,
 236                                        DATA_BLOB *decoded_data,
 237                                        DATA_BLOB *kpasswd_reply,
 238                                        const char **error_string)
 239 {
 240         struct auth_session_info *session_info;
 241         NTSTATUS status;
 242
 243         status = gensec_session_info(gensec_security,
 244                                      mem_ctx,
 245                                      &session_info);
 246         if (!NT_STATUS_IS_OK(status)) {
 247                 *error_string = talloc_asprintf(mem_ctx,
 248                                                 "gensec_session_info failed - %s",
 249                                                 nt_errstr(status));
 250                 return KRB5_KPASSWD_HARDERROR;
 251         }
 252
 253         switch(verno) {
 254         case KRB5_KPASSWD_VERS_CHANGEPW: {
 255                 DATA_BLOB password = data_blob_null;
 256                 bool ok;
 257
 258                 ok = convert_string_talloc_handle(mem_ctx,
 259                                                   lpcfg_iconv_handle(kdc->task->lp_ctx),
 260                                                   CH_UTF8,
 261                                                   CH_UTF16,
 262                                                   (const char *)decoded_data->data,
 263                                                   decoded_data->length,
 264                                                   (void **)&password.data,
 265                                                   &password.length);
 266                 if (!ok) {
 267                         *error_string = "String conversion failed!";
 268                         DBG_WARNING("%s\n", *error_string);
 269                         return KRB5_KPASSWD_HARDERROR;
 270                 }
 271
 272                 return kpasswd_change_password(kdc,
 273                                                mem_ctx,
 274                                                session_info,
 275                                                &password,
 276                                                kpasswd_reply,
 277                                                error_string);
 278         }
 279         case KRB5_KPASSWD_VERS_SETPW: {
 280                 return kpasswd_set_password(kdc,
 281                                             mem_ctx,
 282                                             session_info,
 283                                             decoded_data,
 284                                             kpasswd_reply,
 285                                             error_string);
 286         }
 287         default:
 288                 *error_string = talloc_asprintf(mem_ctx,
 289                                                 "Protocol version %u not supported",
 290                                                 verno);
 291                 return KRB5_KPASSWD_BAD_VERSION;
 292         }
 293
 294         return 0;
 295 }