Logo Search packages:      
Sourcecode: samba4 version File versions  Download package

db-glue.c

/*
   Unix SMB/CIFS implementation.

   Database Glue between Samba and the KDC

   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2009
   Copyright (C) Simo Sorce <idra@samba.org> 2010

   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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "system/time.h"
#include "../libds/common/flags.h"
#include "lib/ldb/include/ldb.h"
#include "librpc/gen_ndr/netlogon.h"
#include "libcli/security/security.h"
#include "auth/auth.h"
#include "auth/credentials/credentials.h"
#include "auth/auth_sam.h"
#include "../lib/util/util_ldb.h"
#include "dsdb/samdb/samdb.h"
#include "dsdb/common/util.h"
#include "librpc/ndr/libndr.h"
#include "librpc/gen_ndr/ndr_drsblobs.h"
#include "librpc/gen_ndr/lsa.h"
#include "libcli/auth/libcli_auth.h"
#include "param/param.h"
#include "../lib/crypto/md4.h"
#include "system/kerberos.h"
#include "auth/kerberos/kerberos.h"
#include <hdb.h>
#include "kdc/samba_kdc.h"
#include "kdc/db-glue.h"

enum samba_kdc_ent_type
{ SAMBA_KDC_ENT_TYPE_CLIENT, SAMBA_KDC_ENT_TYPE_SERVER,
  SAMBA_KDC_ENT_TYPE_KRBTGT, SAMBA_KDC_ENT_TYPE_TRUST, SAMBA_KDC_ENT_TYPE_ANY };

enum trust_direction {
      UNKNOWN = 0,
      INBOUND = LSA_TRUST_DIRECTION_INBOUND,
      OUTBOUND = LSA_TRUST_DIRECTION_OUTBOUND
};

static const char *trust_attrs[] = {
      "trustPartner",
      "trustAuthIncoming",
      "trustAuthOutgoing",
      "whenCreated",
      "msDS-SupportedEncryptionTypes",
      "trustAttributes",
      "trustDirection",
      "trustType",
      NULL
};

static KerberosTime ldb_msg_find_krb5time_ldap_time(struct ldb_message *msg, const char *attr, KerberosTime default_val)
{
    const char *tmp;
    const char *gentime;
    struct tm tm;

    gentime = ldb_msg_find_attr_as_string(msg, attr, NULL);
    if (!gentime)
      return default_val;

    tmp = strptime(gentime, "%Y%m%d%H%M%SZ", &tm);
    if (tmp == NULL) {
          return default_val;
    }

    return timegm(&tm);
}

static HDBFlags uf2HDBFlags(krb5_context context, int userAccountControl, enum samba_kdc_ent_type ent_type)
{
      HDBFlags flags = int2HDBFlags(0);

      /* we don't allow kadmin deletes */
      flags.immutable = 1;

      /* mark the principal as invalid to start with */
      flags.invalid = 1;

      flags.renewable = 1;

      /* All accounts are servers, but this may be disabled again in the caller */
      flags.server = 1;

      /* Account types - clear the invalid bit if it turns out to be valid */
      if (userAccountControl & UF_NORMAL_ACCOUNT) {
            if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
                  flags.client = 1;
            }
            flags.invalid = 0;
      }

      if (userAccountControl & UF_INTERDOMAIN_TRUST_ACCOUNT) {
            if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
                  flags.client = 1;
            }
            flags.invalid = 0;
      }
      if (userAccountControl & UF_WORKSTATION_TRUST_ACCOUNT) {
            if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
                  flags.client = 1;
            }
            flags.invalid = 0;
      }
      if (userAccountControl & UF_SERVER_TRUST_ACCOUNT) {
            if (ent_type == SAMBA_KDC_ENT_TYPE_CLIENT || ent_type == SAMBA_KDC_ENT_TYPE_ANY) {
                  flags.client = 1;
            }
            flags.invalid = 0;
      }

      /* Not permitted to act as a client if disabled */
      if (userAccountControl & UF_ACCOUNTDISABLE) {
            flags.client = 0;
      }
      if (userAccountControl & UF_LOCKOUT) {
            flags.invalid = 1;
      }
/*
      if (userAccountControl & UF_PASSWORD_NOTREQD) {
            flags.invalid = 1;
      }
*/
/*
      UF_PASSWORD_CANT_CHANGE and UF_ENCRYPTED_TEXT_PASSWORD_ALLOWED are irrelevent
*/
      if (userAccountControl & UF_TEMP_DUPLICATE_ACCOUNT) {
            flags.invalid = 1;
      }

/* UF_DONT_EXPIRE_PASSWD and UF_USE_DES_KEY_ONLY handled in samba_kdc_message2entry() */

/*
      if (userAccountControl & UF_MNS_LOGON_ACCOUNT) {
            flags.invalid = 1;
      }
*/
      if (userAccountControl & UF_SMARTCARD_REQUIRED) {
            flags.require_hwauth = 1;
      }
      if (userAccountControl & UF_TRUSTED_FOR_DELEGATION) {
            flags.ok_as_delegate = 1;
      }
      if (!(userAccountControl & UF_NOT_DELEGATED)) {
            flags.forwardable = 1;
            flags.proxiable = 1;
      }

      if (userAccountControl & UF_DONT_REQUIRE_PREAUTH) {
            flags.require_preauth = 0;
      } else {
            flags.require_preauth = 1;

      }
      return flags;
}

static int samba_kdc_entry_destructor(struct samba_kdc_entry *p)
{
    hdb_entry_ex *entry_ex = p->entry_ex;
    free_hdb_entry(&entry_ex->entry);
    return 0;
}

static void samba_kdc_free_entry(krb5_context context, hdb_entry_ex *entry_ex)
{
      /* this function is called only from hdb_free_entry().
       * Make sure we neutralize the destructor or we will
       * get a double free later when hdb_free_entry() will
       * try to call free_hdb_entry() */
      talloc_set_destructor(entry_ex->ctx, NULL);

      /* now proceed to free the talloc part */
      talloc_free(entry_ex->ctx);
}

static krb5_error_code samba_kdc_message2entry_keys(krb5_context context,
                                        TALLOC_CTX *mem_ctx,
                                        struct ldb_message *msg,
                                        uint32_t rid,
                                        unsigned int userAccountControl,
                                        enum samba_kdc_ent_type ent_type,
                                        hdb_entry_ex *entry_ex)
{
      krb5_error_code ret = 0;
      enum ndr_err_code ndr_err;
      struct samr_Password *hash;
      const struct ldb_val *sc_val;
      struct supplementalCredentialsBlob scb;
      struct supplementalCredentialsPackage *scpk = NULL;
      bool newer_keys = false;
      struct package_PrimaryKerberosBlob _pkb;
      struct package_PrimaryKerberosCtr3 *pkb3 = NULL;
      struct package_PrimaryKerberosCtr4 *pkb4 = NULL;
      uint16_t i;
      uint16_t allocated_keys = 0;

      /* Supported Enc for this entry */
      uint32_t supported_enctypes = ENC_ALL_TYPES; /* by default, we support all enc types */

      /* However, if this is a TGS-REQ, then lock it down to a
       * reasonable guess as to what the server can decode.  The
       * krbtgt is special - default to use what is stored for the KDC */
      if (rid != DOMAIN_RID_KRBTGT && ent_type == SAMBA_KDC_ENT_TYPE_SERVER) {
            /* This is the standard set for a server that has not declared a msDS-SupportedEncryptionTypes */
            supported_enctypes = ENC_CRC32 | ENC_RSA_MD5 | ENC_RC4_HMAC_MD5;
      }
      supported_enctypes = ldb_msg_find_attr_as_uint(msg, "msDS-SupportedEncryptionTypes",
                                          supported_enctypes);
      if (rid == DOMAIN_RID_KRBTGT) {
            /* Be double-sure never to use DES here */
            supported_enctypes &= ~(ENC_CRC32|ENC_RSA_MD5);
      }

      switch (ent_type) {
      case SAMBA_KDC_ENT_TYPE_KRBTGT:
      case SAMBA_KDC_ENT_TYPE_TRUST:
            /* Disallow krbtgt and trust tickets to be DES encrypted, it's just too dangerous */
            supported_enctypes &= ~(ENC_CRC32|ENC_RSA_MD5);
            break;
      default:
            break;
            /* No further restrictions */
      }

      /* If UF_USE_DES_KEY_ONLY has been set, then don't allow use of the newer enc types */
      if (userAccountControl & UF_USE_DES_KEY_ONLY) {
            /* However, don't allow use of DES, if we were told not to by msDS-SupportedEncTypes */
            supported_enctypes &= ENC_CRC32|ENC_RSA_MD5;
      }

      entry_ex->entry.keys.val = NULL;
      entry_ex->entry.keys.len = 0;

      entry_ex->entry.kvno = ldb_msg_find_attr_as_int(msg, "msDS-KeyVersionNumber", 0);

      /* Get keys from the db */

      hash = samdb_result_hash(mem_ctx, msg, "unicodePwd");
      sc_val = ldb_msg_find_ldb_val(msg, "supplementalCredentials");

      /* unicodePwd for enctype 0x17 (23) if present */
      if (hash) {
            allocated_keys++;
      }

      /* supplementalCredentials if present */
      if (sc_val) {
            ndr_err = ndr_pull_struct_blob_all(sc_val, mem_ctx, &scb,
                                       (ndr_pull_flags_fn_t)ndr_pull_supplementalCredentialsBlob);
            if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
                  dump_data(0, sc_val->data, sc_val->length);
                  ret = EINVAL;
                  goto out;
            }

            if (scb.sub.signature != SUPPLEMENTAL_CREDENTIALS_SIGNATURE) {
                  NDR_PRINT_DEBUG(supplementalCredentialsBlob, &scb);
                  ret = EINVAL;
                  goto out;
            }

            for (i=0; i < scb.sub.num_packages; i++) {
                  if (strcmp("Primary:Kerberos-Newer-Keys", scb.sub.packages[i].name) == 0) {
                        scpk = &scb.sub.packages[i];
                        if (!scpk->data || !scpk->data[0]) {
                              scpk = NULL;
                              continue;
                        }
                        newer_keys = true;
                        break;
                  } else if (strcmp("Primary:Kerberos", scb.sub.packages[i].name) == 0) {
                        scpk = &scb.sub.packages[i];
                        if (!scpk->data || !scpk->data[0]) {
                              scpk = NULL;
                        }
                        /*
                         * we don't break here in hope to find
                         * a Kerberos-Newer-Keys package
                         */
                  }
            }
      }
      /*
       * Primary:Kerberos-Newer-Keys or Primary:Kerberos element
       * of supplementalCredentials
       */
      if (scpk) {
            DATA_BLOB blob;

            blob = strhex_to_data_blob(mem_ctx, scpk->data);
            if (!blob.data) {
                  ret = ENOMEM;
                  goto out;
            }

            /* we cannot use ndr_pull_struct_blob_all() here, as w2k and w2k3 add padding bytes */
            ndr_err = ndr_pull_struct_blob(&blob, mem_ctx, &_pkb,
                                     (ndr_pull_flags_fn_t)ndr_pull_package_PrimaryKerberosBlob);
            if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
                  ret = EINVAL;
                  krb5_set_error_message(context, ret, "samba_kdc_message2entry_keys: could not parse package_PrimaryKerberosBlob");
                  krb5_warnx(context, "samba_kdc_message2entry_keys: could not parse package_PrimaryKerberosBlob");
                  goto out;
            }

            if (newer_keys && _pkb.version != 4) {
                  ret = EINVAL;
                  krb5_set_error_message(context, ret, "samba_kdc_message2entry_keys: Primary:Kerberos-Newer-Keys not version 4");
                  krb5_warnx(context, "samba_kdc_message2entry_keys: Primary:Kerberos-Newer-Keys not version 4");
                  goto out;
            }

            if (!newer_keys && _pkb.version != 3) {
                  ret = EINVAL;
                  krb5_set_error_message(context, ret, "samba_kdc_message2entry_keys: could not parse Primary:Kerberos not version 3");
                  krb5_warnx(context, "samba_kdc_message2entry_keys: could not parse Primary:Kerberos not version 3");
                  goto out;
            }

            if (_pkb.version == 4) {
                  pkb4 = &_pkb.ctr.ctr4;
                  allocated_keys += pkb4->num_keys;
            } else if (_pkb.version == 3) {
                  pkb3 = &_pkb.ctr.ctr3;
                  allocated_keys += pkb3->num_keys;
            }
      }

      if (allocated_keys == 0) {
            /* oh, no password.  Apparently (comment in
             * hdb-ldap.c) this violates the ASN.1, but this
             * allows an entry with no keys (yet). */
            return 0;
      }

      /* allocate space to decode into */
      entry_ex->entry.keys.len = 0;
      entry_ex->entry.keys.val = calloc(allocated_keys, sizeof(Key));
      if (entry_ex->entry.keys.val == NULL) {
            ret = ENOMEM;
            goto out;
      }

      if (hash && (supported_enctypes & ENC_RC4_HMAC_MD5)) {
            Key key;

            key.mkvno = 0;
            key.salt = NULL; /* No salt for this enc type */

            ret = krb5_keyblock_init(context,
                               ENCTYPE_ARCFOUR_HMAC,
                               hash->hash, sizeof(hash->hash),
                               &key.key);
            if (ret) {
                  goto out;
            }

            entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
            entry_ex->entry.keys.len++;
      }

      if (pkb4) {
            for (i=0; i < pkb4->num_keys; i++) {
                  Key key;

                  if (!pkb4->keys[i].value) continue;

                  if (!(kerberos_enctype_to_bitmap(pkb4->keys[i].keytype) & supported_enctypes)) {
                        continue;
                  }

                  key.mkvno = 0;
                  key.salt = NULL;

                  if (pkb4->salt.string) {
                        DATA_BLOB salt;

                        salt = data_blob_string_const(pkb4->salt.string);

                        key.salt = calloc(1, sizeof(*key.salt));
                        if (key.salt == NULL) {
                              ret = ENOMEM;
                              goto out;
                        }

                        key.salt->type = hdb_pw_salt;

                        ret = krb5_data_copy(&key.salt->salt, salt.data, salt.length);
                        if (ret) {
                              free(key.salt);
                              key.salt = NULL;
                              goto out;
                        }
                  }

                  /* TODO: maybe pass the iteration_count somehow... */

                  ret = krb5_keyblock_init(context,
                                     pkb4->keys[i].keytype,
                                     pkb4->keys[i].value->data,
                                     pkb4->keys[i].value->length,
                                     &key.key);
                  if (ret == KRB5_PROG_ETYPE_NOSUPP) {
                        DEBUG(2,("Unsupported keytype ignored - type %u\n",
                               pkb4->keys[i].keytype));
                        ret = 0;
                        continue;
                  }
                  if (ret) {
                        if (key.salt) {
                              free_Salt(key.salt);
                              free(key.salt);
                              key.salt = NULL;
                        }
                        goto out;
                  }

                  entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
                  entry_ex->entry.keys.len++;
            }
      } else if (pkb3) {
            for (i=0; i < pkb3->num_keys; i++) {
                  Key key;

                  if (!pkb3->keys[i].value) continue;

                  if (!(kerberos_enctype_to_bitmap(pkb3->keys[i].keytype) & supported_enctypes)) {
                        continue;
                  }

                  key.mkvno = 0;
                  key.salt = NULL;

                  if (pkb3->salt.string) {
                        DATA_BLOB salt;

                        salt = data_blob_string_const(pkb3->salt.string);

                        key.salt = calloc(1, sizeof(*key.salt));
                        if (key.salt == NULL) {
                              ret = ENOMEM;
                              goto out;
                        }

                        key.salt->type = hdb_pw_salt;

                        ret = krb5_data_copy(&key.salt->salt, salt.data, salt.length);
                        if (ret) {
                              free(key.salt);
                              key.salt = NULL;
                              goto out;
                        }
                  }

                  ret = krb5_keyblock_init(context,
                                     pkb3->keys[i].keytype,
                                     pkb3->keys[i].value->data,
                                     pkb3->keys[i].value->length,
                                     &key.key);
                  if (ret) {
                        if (key.salt) {
                              free_Salt(key.salt);
                              free(key.salt);
                              key.salt = NULL;
                        }
                        goto out;
                  }

                  entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
                  entry_ex->entry.keys.len++;
            }
      }

out:
      if (ret != 0) {
            entry_ex->entry.keys.len = 0;
      }
      if (entry_ex->entry.keys.len == 0 && entry_ex->entry.keys.val) {
            free(entry_ex->entry.keys.val);
            entry_ex->entry.keys.val = NULL;
      }
      return ret;
}

/*
 * Construct an hdb_entry from a directory entry.
 */
static krb5_error_code samba_kdc_message2entry(krb5_context context,
                               struct samba_kdc_db_context *kdc_db_ctx,
                               TALLOC_CTX *mem_ctx, krb5_const_principal principal,
                               enum samba_kdc_ent_type ent_type,
                               struct ldb_dn *realm_dn,
                               struct ldb_message *msg,
                               hdb_entry_ex *entry_ex)
{
      struct loadparm_context *lp_ctx = kdc_db_ctx->lp_ctx;
      unsigned int userAccountControl;
      unsigned int i;
      krb5_error_code ret = 0;
      krb5_boolean is_computer = FALSE;
      char *realm = strupper_talloc(mem_ctx, lpcfg_realm(lp_ctx));

      struct samba_kdc_entry *p;
      NTTIME acct_expiry;
      NTSTATUS status;

      uint32_t rid;
      struct ldb_message_element *objectclasses;
      struct ldb_val computer_val;
      const char *samAccountName = ldb_msg_find_attr_as_string(msg, "samAccountName", NULL);
      computer_val.data = discard_const_p(uint8_t,"computer");
      computer_val.length = strlen((const char *)computer_val.data);

      if (!samAccountName) {
            ret = ENOENT;
            krb5_set_error_message(context, ret, "samba_kdc_message2entry: no samAccountName present");
            goto out;
      }

      objectclasses = ldb_msg_find_element(msg, "objectClass");

      if (objectclasses && ldb_msg_find_val(objectclasses, &computer_val)) {
            is_computer = TRUE;
      }

      memset(entry_ex, 0, sizeof(*entry_ex));

      if (!realm) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "talloc_strdup: out of memory");
            goto out;
      }

      p = talloc(mem_ctx, struct samba_kdc_entry);
      if (!p) {
            ret = ENOMEM;
            goto out;
      }

      p->kdc_db_ctx = kdc_db_ctx;
      p->entry_ex = entry_ex;
      p->realm_dn = talloc_reference(p, realm_dn);
      if (!p->realm_dn) {
            ret = ENOMEM;
            goto out;
      }

      talloc_set_destructor(p, samba_kdc_entry_destructor);

      /* make sure we do not have bogus data in there */
      memset(&entry_ex->entry, 0, sizeof(hdb_entry));

      entry_ex->ctx = p;
      entry_ex->free_entry = samba_kdc_free_entry;

      userAccountControl = ldb_msg_find_attr_as_uint(msg, "userAccountControl", 0);


      entry_ex->entry.principal = malloc(sizeof(*(entry_ex->entry.principal)));
      if (ent_type == SAMBA_KDC_ENT_TYPE_ANY && principal == NULL) {
            krb5_make_principal(context, &entry_ex->entry.principal, realm, samAccountName, NULL);
      } else {
            ret = copy_Principal(principal, entry_ex->entry.principal);
            if (ret) {
                  krb5_clear_error_message(context);
                  goto out;
            }

            /* While we have copied the client principal, tests
             * show that Win2k3 returns the 'corrected' realm, not
             * the client-specified realm.  This code attempts to
             * replace the client principal's realm with the one
             * we determine from our records */

            /* this has to be with malloc() */
            krb5_principal_set_realm(context, entry_ex->entry.principal, realm);
      }

      /* First try and figure out the flags based on the userAccountControl */
      entry_ex->entry.flags = uf2HDBFlags(context, userAccountControl, ent_type);

      /* Windows 2008 seems to enforce this (very sensible) rule by
       * default - don't allow offline attacks on a user's password
       * by asking for a ticket to them as a service (encrypted with
       * their probably patheticly insecure password) */

      if (entry_ex->entry.flags.server
          && lpcfg_parm_bool(lp_ctx, NULL, "kdc", "require spn for service", true)) {
            if (!is_computer && !ldb_msg_find_attr_as_string(msg, "servicePrincipalName", NULL)) {
                  entry_ex->entry.flags.server = 0;
            }
      }

      {
            /* These (created_by, modified_by) parts of the entry are not relevant for Samba4's use
             * of the Heimdal KDC.  They are stored in a the traditional
             * DB for audit purposes, and still form part of the structure
             * we must return */

            /* use 'whenCreated' */
            entry_ex->entry.created_by.time = ldb_msg_find_krb5time_ldap_time(msg, "whenCreated", 0);
            /* use 'kadmin' for now (needed by mit_samba) */
            krb5_make_principal(context,
                            &entry_ex->entry.created_by.principal,
                            realm, "kadmin", NULL);

            entry_ex->entry.modified_by = (Event *) malloc(sizeof(Event));
            if (entry_ex->entry.modified_by == NULL) {
                  ret = ENOMEM;
                  krb5_set_error_message(context, ret, "malloc: out of memory");
                  goto out;
            }

            /* use 'whenChanged' */
            entry_ex->entry.modified_by->time = ldb_msg_find_krb5time_ldap_time(msg, "whenChanged", 0);
            /* use 'kadmin' for now (needed by mit_samba) */
            krb5_make_principal(context,
                            &entry_ex->entry.modified_by->principal,
                            realm, "kadmin", NULL);
      }


      /* The lack of password controls etc applies to krbtgt by
       * virtue of being that particular RID */
      status = dom_sid_split_rid(NULL, samdb_result_dom_sid(mem_ctx, msg, "objectSid"), NULL, &rid);

      if (!NT_STATUS_IS_OK(status)) {
            ret = EINVAL;
            goto out;
      }

      if (rid == DOMAIN_RID_KRBTGT) {
            entry_ex->entry.valid_end = NULL;
            entry_ex->entry.pw_end = NULL;

            entry_ex->entry.flags.invalid = 0;
            entry_ex->entry.flags.server = 1;

            /* Don't mark all requests for the krbtgt/realm as
             * 'change password', as otherwise we could get into
             * trouble, and not enforce the password expirty.
             * Instead, only do it when request is for the kpasswd service */
            if (ent_type == SAMBA_KDC_ENT_TYPE_SERVER
                && principal->name.name_string.len == 2
                && (strcmp(principal->name.name_string.val[0], "kadmin") == 0)
                && (strcmp(principal->name.name_string.val[1], "changepw") == 0)
                && lpcfg_is_my_domain_or_realm(lp_ctx, principal->realm)) {
                  entry_ex->entry.flags.change_pw = 1;
            }
            entry_ex->entry.flags.client = 0;
            entry_ex->entry.flags.forwardable = 1;
            entry_ex->entry.flags.ok_as_delegate = 1;
      } else if (entry_ex->entry.flags.server && ent_type == SAMBA_KDC_ENT_TYPE_SERVER) {
            /* The account/password expiry only applies when the account is used as a
             * client (ie password login), not when used as a server */

            /* Make very well sure we don't use this for a client,
             * it could bypass the password restrictions */
            entry_ex->entry.flags.client = 0;

            entry_ex->entry.valid_end = NULL;
            entry_ex->entry.pw_end = NULL;

      } else {
            NTTIME must_change_time
                  = samdb_result_force_password_change(kdc_db_ctx->samdb, mem_ctx,
                                               realm_dn, msg);
            if (must_change_time == 0x7FFFFFFFFFFFFFFFULL) {
                  entry_ex->entry.pw_end = NULL;
            } else {
                  entry_ex->entry.pw_end = malloc(sizeof(*entry_ex->entry.pw_end));
                  if (entry_ex->entry.pw_end == NULL) {
                        ret = ENOMEM;
                        goto out;
                  }
                  *entry_ex->entry.pw_end = nt_time_to_unix(must_change_time);
            }

            acct_expiry = samdb_result_account_expires(msg);
            if (acct_expiry == 0x7FFFFFFFFFFFFFFFULL) {
                  entry_ex->entry.valid_end = NULL;
            } else {
                  entry_ex->entry.valid_end = malloc(sizeof(*entry_ex->entry.valid_end));
                  if (entry_ex->entry.valid_end == NULL) {
                        ret = ENOMEM;
                        goto out;
                  }
                  *entry_ex->entry.valid_end = nt_time_to_unix(acct_expiry);
            }
      }

      entry_ex->entry.valid_start = NULL;

      entry_ex->entry.max_life = NULL;

      entry_ex->entry.max_renew = NULL;

      entry_ex->entry.generation = NULL;

      /* Get keys from the db */
      ret = samba_kdc_message2entry_keys(context, p, msg, 
                                 rid, userAccountControl,
                                 ent_type, entry_ex);
      if (ret) {
            /* Could be bougus data in the entry, or out of memory */
            goto out;
      }

      entry_ex->entry.etypes = malloc(sizeof(*(entry_ex->entry.etypes)));
      if (entry_ex->entry.etypes == NULL) {
            krb5_clear_error_message(context);
            ret = ENOMEM;
            goto out;
      }
      entry_ex->entry.etypes->len = entry_ex->entry.keys.len;
      entry_ex->entry.etypes->val = calloc(entry_ex->entry.etypes->len, sizeof(int));
      if (entry_ex->entry.etypes->val == NULL) {
            krb5_clear_error_message(context);
            ret = ENOMEM;
            goto out;
      }
      for (i=0; i < entry_ex->entry.etypes->len; i++) {
            entry_ex->entry.etypes->val[i] = entry_ex->entry.keys.val[i].key.keytype;
      }


      p->msg = talloc_steal(p, msg);

out:
      if (ret != 0) {
            /* This doesn't free ent itself, that is for the eventual caller to do */
            hdb_free_entry(context, entry_ex);
      } else {
            talloc_steal(kdc_db_ctx, entry_ex->ctx);
      }

      return ret;
}

/*
 * Construct an hdb_entry from a directory entry.
 */
static krb5_error_code samba_kdc_trust_message2entry(krb5_context context,
                                     struct samba_kdc_db_context *kdc_db_ctx,
                                     TALLOC_CTX *mem_ctx, krb5_const_principal principal,
                                     enum trust_direction direction,
                                     struct ldb_dn *realm_dn,
                                     struct ldb_message *msg,
                                     hdb_entry_ex *entry_ex)
{
      struct loadparm_context *lp_ctx = kdc_db_ctx->lp_ctx;
      const char *dnsdomain;
      char *realm = strupper_talloc(mem_ctx, lpcfg_realm(lp_ctx));
      DATA_BLOB password_utf16;
      struct samr_Password password_hash;
      const struct ldb_val *password_val;
      struct trustAuthInOutBlob password_blob;
      struct samba_kdc_entry *p;

      enum ndr_err_code ndr_err;
      int ret, trust_direction_flags;
      unsigned int i;

      p = talloc(mem_ctx, struct samba_kdc_entry);
      if (!p) {
            ret = ENOMEM;
            goto out;
      }

      p->kdc_db_ctx = kdc_db_ctx;
      p->entry_ex = entry_ex;
      p->realm_dn = realm_dn;

      talloc_set_destructor(p, samba_kdc_entry_destructor);

      /* make sure we do not have bogus data in there */
      memset(&entry_ex->entry, 0, sizeof(hdb_entry));

      entry_ex->ctx = p;
      entry_ex->free_entry = samba_kdc_free_entry;

      /* use 'whenCreated' */
      entry_ex->entry.created_by.time = ldb_msg_find_krb5time_ldap_time(msg, "whenCreated", 0);
      /* use 'kadmin' for now (needed by mit_samba) */
      krb5_make_principal(context,
                      &entry_ex->entry.created_by.principal,
                      realm, "kadmin", NULL);

      entry_ex->entry.valid_start = NULL;

      trust_direction_flags = ldb_msg_find_attr_as_int(msg, "trustDirection", 0);

      if (direction == INBOUND) {
            password_val = ldb_msg_find_ldb_val(msg, "trustAuthIncoming");

      } else { /* OUTBOUND */
            dnsdomain = ldb_msg_find_attr_as_string(msg, "trustPartner", NULL);
            /* replace realm */
            talloc_free(realm);
            realm = strupper_talloc(mem_ctx, dnsdomain);
            password_val = ldb_msg_find_ldb_val(msg, "trustAuthOutgoing");
      }

      if (!password_val || !(trust_direction_flags & direction)) {
            ret = ENOENT;
            goto out;
      }

      ndr_err = ndr_pull_struct_blob(password_val, mem_ctx, &password_blob,
                                 (ndr_pull_flags_fn_t)ndr_pull_trustAuthInOutBlob);
      if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
            ret = EINVAL;
            goto out;
      }

      entry_ex->entry.kvno = -1;
      for (i=0; i < password_blob.count; i++) {
            if (password_blob.current->array[i].AuthType == TRUST_AUTH_TYPE_VERSION) {
                  entry_ex->entry.kvno = password_blob.current->array[i].AuthInfo.version.version;
            }
      }

      for (i=0; i < password_blob.count; i++) {
            if (password_blob.current->array[i].AuthType == TRUST_AUTH_TYPE_CLEAR) {
                  password_utf16 = data_blob_const(password_blob.current->array[i].AuthInfo.clear.password,
                                           password_blob.current->array[i].AuthInfo.clear.size);
                  /* In the future, generate all sorts of
                   * hashes, but for now we can't safely convert
                   * the random strings windows uses into
                   * utf8 */

                  /* but as it is utf16 already, we can get the NT password/arcfour-hmac-md5 key */
                  mdfour(password_hash.hash, password_utf16.data, password_utf16.length);
                  break;
            } else if (password_blob.current->array[i].AuthType == TRUST_AUTH_TYPE_NT4OWF) {
                  password_hash = password_blob.current->array[i].AuthInfo.nt4owf.password;
                  break;
            }
      }

      if (i < password_blob.count) {
            Key key;
            /* Must have found a cleartext or MD4 password */
            entry_ex->entry.keys.val = calloc(1, sizeof(Key));

            key.mkvno = 0;
            key.salt = NULL; /* No salt for this enc type */

            if (entry_ex->entry.keys.val == NULL) {
                  ret = ENOMEM;
                  goto out;
            }

            ret = krb5_keyblock_init(context,
                               ENCTYPE_ARCFOUR_HMAC,
                               password_hash.hash, sizeof(password_hash.hash),
                               &key.key);

            entry_ex->entry.keys.val[entry_ex->entry.keys.len] = key;
            entry_ex->entry.keys.len++;
      }

      entry_ex->entry.principal = malloc(sizeof(*(entry_ex->entry.principal)));

      ret = copy_Principal(principal, entry_ex->entry.principal);
      if (ret) {
            krb5_clear_error_message(context);
            goto out;
      }

      /* While we have copied the client principal, tests
       * show that Win2k3 returns the 'corrected' realm, not
       * the client-specified realm.  This code attempts to
       * replace the client principal's realm with the one
       * we determine from our records */

      krb5_principal_set_realm(context, entry_ex->entry.principal, realm);
      entry_ex->entry.flags = int2HDBFlags(0);
      entry_ex->entry.flags.immutable = 1;
      entry_ex->entry.flags.invalid = 0;
      entry_ex->entry.flags.server = 1;
      entry_ex->entry.flags.require_preauth = 1;

      entry_ex->entry.pw_end = NULL;

      entry_ex->entry.max_life = NULL;

      entry_ex->entry.max_renew = NULL;

      entry_ex->entry.generation = NULL;

      entry_ex->entry.etypes = malloc(sizeof(*(entry_ex->entry.etypes)));
      if (entry_ex->entry.etypes == NULL) {
            krb5_clear_error_message(context);
            ret = ENOMEM;
            goto out;
      }
      entry_ex->entry.etypes->len = entry_ex->entry.keys.len;
      entry_ex->entry.etypes->val = calloc(entry_ex->entry.etypes->len, sizeof(int));
      if (entry_ex->entry.etypes->val == NULL) {
            krb5_clear_error_message(context);
            ret = ENOMEM;
            goto out;
      }
      for (i=0; i < entry_ex->entry.etypes->len; i++) {
            entry_ex->entry.etypes->val[i] = entry_ex->entry.keys.val[i].key.keytype;
      }


      p->msg = talloc_steal(p, msg);

out:
      if (ret != 0) {
            /* This doesn't free ent itself, that is for the eventual caller to do */
            hdb_free_entry(context, entry_ex);
      } else {
            talloc_steal(kdc_db_ctx, entry_ex->ctx);
      }

      return ret;

}

static krb5_error_code samba_kdc_lookup_trust(krb5_context context, struct ldb_context *ldb_ctx,
                              TALLOC_CTX *mem_ctx,
                              const char *realm,
                              struct ldb_dn *realm_dn,
                              struct ldb_message **pmsg)
{
      int lret;
      krb5_error_code ret;
      char *filter = NULL;
      const char * const *attrs = trust_attrs;

      struct ldb_result *res = NULL;
      filter = talloc_asprintf(mem_ctx, "(&(objectClass=trustedDomain)(|(flatname=%s)(trustPartner=%s)))", realm, realm);

      if (!filter) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "talloc_asprintf: out of memory");
            return ret;
      }

      lret = ldb_search(ldb_ctx, mem_ctx, &res,
                    ldb_get_default_basedn(ldb_ctx),
                    LDB_SCOPE_SUBTREE, attrs, "%s", filter);
      if (lret != LDB_SUCCESS) {
            DEBUG(3, ("Failed to search for %s: %s\n", filter, ldb_errstring(ldb_ctx)));
            return HDB_ERR_NOENTRY;
      } else if (res->count == 0 || res->count > 1) {
            DEBUG(3, ("Failed find a single entry for %s: got %d\n", filter, res->count));
            talloc_free(res);
            return HDB_ERR_NOENTRY;
      }
      talloc_steal(mem_ctx, res->msgs);
      *pmsg = res->msgs[0];
      talloc_free(res);
      return 0;
}

static krb5_error_code samba_kdc_lookup_client(krb5_context context,
                                    struct samba_kdc_db_context *kdc_db_ctx,
                                    TALLOC_CTX *mem_ctx,
                                    krb5_const_principal principal,
                                    const char **attrs,
                                    struct ldb_dn **realm_dn,
                                    struct ldb_message **msg) {
      NTSTATUS nt_status;
      char *principal_string;
      krb5_error_code ret;

      ret = krb5_unparse_name(context, principal, &principal_string);

      if (ret != 0) {
            return ret;
      }

      nt_status = sam_get_results_principal(kdc_db_ctx->samdb,
                                    mem_ctx, principal_string, attrs,
                                    realm_dn, msg);
      free(principal_string);
      if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_SUCH_USER)) {
            return HDB_ERR_NOENTRY;
      } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_MEMORY)) {
            return ENOMEM;
      } else if (!NT_STATUS_IS_OK(nt_status)) {
            return EINVAL;
      }

      return ret;
}

static krb5_error_code samba_kdc_fetch_client(krb5_context context,
                                     struct samba_kdc_db_context *kdc_db_ctx,
                                     TALLOC_CTX *mem_ctx,
                                     krb5_const_principal principal,
                                     hdb_entry_ex *entry_ex) {
      struct ldb_dn *realm_dn;
      krb5_error_code ret;
      struct ldb_message *msg = NULL;

      ret = samba_kdc_lookup_client(context, kdc_db_ctx,
                               mem_ctx, principal, user_attrs,
                               &realm_dn, &msg);
      if (ret != 0) {
            return ret;
      }

      ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
                               principal, SAMBA_KDC_ENT_TYPE_CLIENT,
                               realm_dn, msg, entry_ex);
      return ret;
}

static krb5_error_code samba_kdc_fetch_krbtgt(krb5_context context,
                              struct samba_kdc_db_context *kdc_db_ctx,
                              TALLOC_CTX *mem_ctx,
                              krb5_const_principal principal,
                              hdb_entry_ex *entry_ex)
{
      struct loadparm_context *lp_ctx = kdc_db_ctx->lp_ctx;
      krb5_error_code ret;
      struct ldb_message *msg = NULL;
      struct ldb_dn *realm_dn = ldb_get_default_basedn(kdc_db_ctx->samdb);
      const char *realm;

      krb5_principal alloc_principal = NULL;
      if (principal->name.name_string.len != 2
          || (strcmp(principal->name.name_string.val[0], KRB5_TGS_NAME) != 0)) {
            /* Not a krbtgt */
            return HDB_ERR_NOENTRY;
      }

      /* krbtgt case.  Either us or a trusted realm */

      if (lpcfg_is_my_domain_or_realm(lp_ctx, principal->realm)
          && lpcfg_is_my_domain_or_realm(lp_ctx, principal->name.name_string.val[1])) {
            /* us */
            /* Cludge, cludge cludge.  If the realm part of krbtgt/realm,
             * is in our db, then direct the caller at our primary
             * krbtgt */

            int lret;
            char *realm_fixed;

            lret = dsdb_search_one(kdc_db_ctx->samdb, mem_ctx,
                               &msg, realm_dn, LDB_SCOPE_SUBTREE,
                               krbtgt_attrs,
                               DSDB_SEARCH_SHOW_EXTENDED_DN,
                               "(&(objectClass=user)(samAccountName=krbtgt))");
            if (lret == LDB_ERR_NO_SUCH_OBJECT) {
                  krb5_warnx(context, "samba_kdc_fetch: could not find own KRBTGT in DB!");
                  krb5_set_error_message(context, HDB_ERR_NOENTRY, "samba_kdc_fetch: could not find own KRBTGT in DB!");
                  return HDB_ERR_NOENTRY;
            } else if (lret != LDB_SUCCESS) {
                  krb5_warnx(context, "samba_kdc_fetch: could not find own KRBTGT in DB: %s", ldb_errstring(kdc_db_ctx->samdb));
                  krb5_set_error_message(context, HDB_ERR_NOENTRY, "samba_kdc_fetch: could not find own KRBTGT in DB: %s", ldb_errstring(kdc_db_ctx->samdb));
                  return HDB_ERR_NOENTRY;
            }

            realm_fixed = strupper_talloc(mem_ctx, lpcfg_realm(lp_ctx));
            if (!realm_fixed) {
                  ret = ENOMEM;
                  krb5_set_error_message(context, ret, "strupper_talloc: out of memory");
                  return ret;
            }

            ret = krb5_copy_principal(context, principal, &alloc_principal);
            if (ret) {
                  return ret;
            }

            free(alloc_principal->name.name_string.val[1]);
            alloc_principal->name.name_string.val[1] = strdup(realm_fixed);
            talloc_free(realm_fixed);
            if (!alloc_principal->name.name_string.val[1]) {
                  ret = ENOMEM;
                  krb5_set_error_message(context, ret, "samba_kdc_fetch: strdup() failed!");
                  return ret;
            }
            principal = alloc_principal;

            ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
                              principal, SAMBA_KDC_ENT_TYPE_KRBTGT,
                              realm_dn, msg, entry_ex);
            if (ret != 0) {
                  krb5_warnx(context, "samba_kdc_fetch: self krbtgt message2entry failed");
            }
            return ret;

      } else {
            enum trust_direction direction = UNKNOWN;

            /* Either an inbound or outbound trust */

            if (strcasecmp(lpcfg_realm(lp_ctx), principal->realm) == 0) {
                  /* look for inbound trust */
                  direction = INBOUND;
                  realm = principal->name.name_string.val[1];
            }

            if (strcasecmp(lpcfg_realm(lp_ctx), principal->name.name_string.val[1]) == 0) {
                  /* look for outbound trust */
                  direction = OUTBOUND;
                  realm = principal->realm;
            }

            /* Trusted domains are under CN=system */

            ret = samba_kdc_lookup_trust(context, kdc_db_ctx->samdb,
                               mem_ctx,
                               realm, realm_dn, &msg);

            if (ret != 0) {
                  krb5_warnx(context, "samba_kdc_fetch: could not find principal in DB");
                  krb5_set_error_message(context, ret, "samba_kdc_fetch: could not find principal in DB");
                  return ret;
            }

            ret = samba_kdc_trust_message2entry(context, kdc_db_ctx, mem_ctx,
                                    principal, direction,
                                    realm_dn, msg, entry_ex);
            if (ret != 0) {
                  krb5_warnx(context, "samba_kdc_fetch: trust_message2entry failed");
            }
            return ret;
      }

}

static krb5_error_code samba_kdc_lookup_server(krb5_context context,
                                    struct samba_kdc_db_context *kdc_db_ctx,
                                    TALLOC_CTX *mem_ctx,
                                    krb5_const_principal principal,
                                    const char **attrs,
                                    struct ldb_dn **realm_dn,
                                    struct ldb_message **msg)
{
      krb5_error_code ret;
      const char *realm;
      if (principal->name.name_string.len >= 2) {
            /* 'normal server' case */
            int ldb_ret;
            NTSTATUS nt_status;
            struct ldb_dn *user_dn;
            char *principal_string;

            ret = krb5_unparse_name_flags(context, principal,
                                    KRB5_PRINCIPAL_UNPARSE_NO_REALM,
                                    &principal_string);
            if (ret != 0) {
                  return ret;
            }

            /* At this point we may find the host is known to be
             * in a different realm, so we should generate a
             * referral instead */
            nt_status = crack_service_principal_name(kdc_db_ctx->samdb,
                                           mem_ctx, principal_string,
                                           &user_dn, realm_dn);
            free(principal_string);

            if (!NT_STATUS_IS_OK(nt_status)) {
                  return HDB_ERR_NOENTRY;
            }

            ldb_ret = dsdb_search_one(kdc_db_ctx->samdb,
                                mem_ctx,
                                msg, user_dn, LDB_SCOPE_BASE,
                                attrs, DSDB_SEARCH_SHOW_EXTENDED_DN, "(objectClass=*)");
            if (ldb_ret != LDB_SUCCESS) {
                  return HDB_ERR_NOENTRY;
            }

      } else {
            int lret;
            char *filter = NULL;
            char *short_princ;
            /* server as client principal case, but we must not lookup userPrincipalNames */
            *realm_dn = ldb_get_default_basedn(kdc_db_ctx->samdb);
            realm = krb5_principal_get_realm(context, principal);

            /* TODO: Check if it is our realm, otherwise give referall */

            ret = krb5_unparse_name_flags(context, principal,  KRB5_PRINCIPAL_UNPARSE_NO_REALM, &short_princ);

            if (ret != 0) {
                  krb5_set_error_message(context, ret, "samba_kdc_lookup_principal: could not parse principal");
                  krb5_warnx(context, "samba_kdc_lookup_principal: could not parse principal");
                  return ret;
            }

            lret = dsdb_search_one(kdc_db_ctx->samdb, mem_ctx, msg,
                               *realm_dn, LDB_SCOPE_SUBTREE,
                               attrs,
                               DSDB_SEARCH_SHOW_EXTENDED_DN,
                               "(&(objectClass=user)(samAccountName=%s))",
                               ldb_binary_encode_string(mem_ctx, short_princ));
            free(short_princ);
            if (lret == LDB_ERR_NO_SUCH_OBJECT) {
                  DEBUG(3, ("Failed find a entry for %s\n", filter));
                  return HDB_ERR_NOENTRY;
            }
            if (lret != LDB_SUCCESS) {
                  DEBUG(3, ("Failed single search for for %s - %s\n",
                          filter, ldb_errstring(kdc_db_ctx->samdb)));
                  return HDB_ERR_NOENTRY;
            }
      }

      return 0;
}

static krb5_error_code samba_kdc_fetch_server(krb5_context context,
                                     struct samba_kdc_db_context *kdc_db_ctx,
                                     TALLOC_CTX *mem_ctx,
                                     krb5_const_principal principal,
                                     hdb_entry_ex *entry_ex)
{
      krb5_error_code ret;
      struct ldb_dn *realm_dn;
      struct ldb_message *msg;

      ret = samba_kdc_lookup_server(context, kdc_db_ctx, mem_ctx, principal,
                               server_attrs, &realm_dn, &msg);
      if (ret != 0) {
            return ret;
      }

      ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
                        principal, SAMBA_KDC_ENT_TYPE_SERVER,
                        realm_dn, msg, entry_ex);
      if (ret != 0) {
            krb5_warnx(context, "samba_kdc_fetch: message2entry failed");
      }

      return ret;
}

krb5_error_code samba_kdc_fetch(krb5_context context,
                        struct samba_kdc_db_context *kdc_db_ctx,
                        krb5_const_principal principal,
                        unsigned flags,
                        hdb_entry_ex *entry_ex)
{
      krb5_error_code ret = HDB_ERR_NOENTRY;
      TALLOC_CTX *mem_ctx = talloc_named(kdc_db_ctx, 0, "samba_kdc_fetch context");

      if (!mem_ctx) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "samba_kdc_fetch: talloc_named() failed!");
            return ret;
      }

      if (flags & HDB_F_GET_CLIENT) {
            ret = samba_kdc_fetch_client(context, kdc_db_ctx, mem_ctx, principal, entry_ex);
            if (ret != HDB_ERR_NOENTRY) goto done;
      }
      if (flags & HDB_F_GET_SERVER) {
            /* krbtgt fits into this situation for trusted realms, and for resolving different versions of our own realm name */
            ret = samba_kdc_fetch_krbtgt(context, kdc_db_ctx, mem_ctx, principal, entry_ex);
            if (ret != HDB_ERR_NOENTRY) goto done;

            /* We return 'no entry' if it does not start with krbtgt/, so move to the common case quickly */
            ret = samba_kdc_fetch_server(context, kdc_db_ctx, mem_ctx, principal, entry_ex);
            if (ret != HDB_ERR_NOENTRY) goto done;
      }
      if (flags & HDB_F_GET_KRBTGT) {
            ret = samba_kdc_fetch_krbtgt(context, kdc_db_ctx, mem_ctx, principal, entry_ex);
            if (ret != HDB_ERR_NOENTRY) goto done;
      }

done:
      talloc_free(mem_ctx);
      return ret;
}

struct samba_kdc_seq {
      unsigned int index;
      unsigned int count;
      struct ldb_message **msgs;
      struct ldb_dn *realm_dn;
};

static krb5_error_code samba_kdc_seq(krb5_context context,
                             struct samba_kdc_db_context *kdc_db_ctx,
                             hdb_entry_ex *entry)
{
      krb5_error_code ret;
      struct samba_kdc_seq *priv = kdc_db_ctx->seq_ctx;
      TALLOC_CTX *mem_ctx;
      hdb_entry_ex entry_ex;
      memset(&entry_ex, '\0', sizeof(entry_ex));

      if (!priv) {
            return HDB_ERR_NOENTRY;
      }

      mem_ctx = talloc_named(priv, 0, "samba_kdc_seq context");

      if (!mem_ctx) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "samba_kdc_seq: talloc_named() failed!");
            return ret;
      }

      if (priv->index < priv->count) {
            ret = samba_kdc_message2entry(context, kdc_db_ctx, mem_ctx,
                              NULL, SAMBA_KDC_ENT_TYPE_ANY,
                              priv->realm_dn, priv->msgs[priv->index++], entry);
      } else {
            ret = HDB_ERR_NOENTRY;
      }

      if (ret != 0) {
            TALLOC_FREE(priv);
            kdc_db_ctx->seq_ctx = NULL;
      } else {
            talloc_free(mem_ctx);
      }

      return ret;
}

krb5_error_code samba_kdc_firstkey(krb5_context context,
                           struct samba_kdc_db_context *kdc_db_ctx,
                           hdb_entry_ex *entry)
{
      struct ldb_context *ldb_ctx = kdc_db_ctx->samdb;
      struct samba_kdc_seq *priv = kdc_db_ctx->seq_ctx;
      char *realm;
      struct ldb_result *res = NULL;
      krb5_error_code ret;
      TALLOC_CTX *mem_ctx;
      int lret;

      if (priv) {
            TALLOC_FREE(priv);
            kdc_db_ctx->seq_ctx = NULL;
      }

      priv = (struct samba_kdc_seq *) talloc(kdc_db_ctx, struct samba_kdc_seq);
      if (!priv) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "talloc: out of memory");
            return ret;
      }

      priv->index = 0;
      priv->msgs = NULL;
      priv->realm_dn = ldb_get_default_basedn(ldb_ctx);
      priv->count = 0;

      mem_ctx = talloc_named(priv, 0, "samba_kdc_firstkey context");

      if (!mem_ctx) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "samba_kdc_firstkey: talloc_named() failed!");
            return ret;
      }

      ret = krb5_get_default_realm(context, &realm);
      if (ret != 0) {
            TALLOC_FREE(priv);
            return ret;
      }

      lret = ldb_search(ldb_ctx, priv, &res,
                    priv->realm_dn, LDB_SCOPE_SUBTREE, user_attrs,
                    "(objectClass=user)");

      if (lret != LDB_SUCCESS) {
            TALLOC_FREE(priv);
            return HDB_ERR_NOENTRY;
      }

      priv->count = res->count;
      priv->msgs = talloc_steal(priv, res->msgs);
      talloc_free(res);

      kdc_db_ctx->seq_ctx = priv;

      ret = samba_kdc_seq(context, kdc_db_ctx, entry);

      if (ret != 0) {
            TALLOC_FREE(priv);
            kdc_db_ctx->seq_ctx = NULL;
      } else {
            talloc_free(mem_ctx);
      }
      return ret;
}

krb5_error_code samba_kdc_nextkey(krb5_context context,
                          struct samba_kdc_db_context *kdc_db_ctx,
                          hdb_entry_ex *entry)
{
      return samba_kdc_seq(context, kdc_db_ctx, entry);
}

/* Check if a given entry may delegate or do s4u2self to this target principal
 *
 * This is currently a very nasty hack - allowing only delegation to itself.
 *
 * This is shared between the constrained delegation and S4U2Self code.
 */
krb5_error_code
samba_kdc_check_identical_client_and_server(krb5_context context,
                                  struct samba_kdc_db_context *kdc_db_ctx,
                                  hdb_entry_ex *entry,
                                  krb5_const_principal target_principal)
{
      krb5_error_code ret;
      krb5_principal enterprise_prinicpal = NULL;
      struct ldb_dn *realm_dn;
      struct ldb_message *msg;
      struct dom_sid *orig_sid;
      struct dom_sid *target_sid;
      struct samba_kdc_entry *p = talloc_get_type(entry->ctx, struct samba_kdc_entry);
      const char *delegation_check_attrs[] = {
            "objectSid", NULL
      };

      TALLOC_CTX *mem_ctx = talloc_named(kdc_db_ctx, 0, "samba_kdc_check_constrained_delegation");

      if (!mem_ctx) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "samba_kdc_fetch: talloc_named() failed!");
            return ret;
      }

      if (target_principal->name.name_type == KRB5_NT_ENTERPRISE_PRINCIPAL) {
            /* Need to reparse the enterprise principal to find the real target */
            if (target_principal->name.name_string.len != 1) {
                  ret = KRB5_PARSE_MALFORMED;
                  krb5_set_error_message(context, ret, "samba_kdc_check_constrained_delegation: request for delegation to enterprise principal with wrong (%d) number of components",
                                     target_principal->name.name_string.len);
                  talloc_free(mem_ctx);
                  return ret;
            }
            ret = krb5_parse_name(context, target_principal->name.name_string.val[0],
                              &enterprise_prinicpal);
            if (ret) {
                  talloc_free(mem_ctx);
                  return ret;
            }
            target_principal = enterprise_prinicpal;
      }

      ret = samba_kdc_lookup_server(context, kdc_db_ctx, mem_ctx, target_principal,
                               delegation_check_attrs, &realm_dn, &msg);

      krb5_free_principal(context, enterprise_prinicpal);

      if (ret != 0) {
            talloc_free(mem_ctx);
            return ret;
      }

      orig_sid = samdb_result_dom_sid(mem_ctx, p->msg, "objectSid");
      target_sid = samdb_result_dom_sid(mem_ctx, msg, "objectSid");

      /* Allow delegation to the same principal, even if by a different
       * name.  The easy and safe way to prove this is by SID
       * comparison */
      if (!(orig_sid && target_sid && dom_sid_equal(orig_sid, target_sid))) {
            talloc_free(mem_ctx);
            return KRB5KDC_ERR_BADOPTION;
      }

      talloc_free(mem_ctx);
      return ret;
}

/* Certificates printed by a the Certificate Authority might have a
 * slightly different form of the user principal name to that in the
 * database.  Allow a mismatch where they both refer to the same
 * SID */

krb5_error_code
samba_kdc_check_pkinit_ms_upn_match(krb5_context context,
                            struct samba_kdc_db_context *kdc_db_ctx,
                             hdb_entry_ex *entry,
                             krb5_const_principal certificate_principal)
{
      krb5_error_code ret;
      struct ldb_dn *realm_dn;
      struct ldb_message *msg;
      struct dom_sid *orig_sid;
      struct dom_sid *target_sid;
      struct samba_kdc_entry *p = talloc_get_type(entry->ctx, struct samba_kdc_entry);
      const char *ms_upn_check_attrs[] = {
            "objectSid", NULL
      };

      TALLOC_CTX *mem_ctx = talloc_named(kdc_db_ctx, 0, "samba_kdc_check_pkinit_ms_upn_match");

      if (!mem_ctx) {
            ret = ENOMEM;
            krb5_set_error_message(context, ret, "samba_kdc_fetch: talloc_named() failed!");
            return ret;
      }

      ret = samba_kdc_lookup_client(context, kdc_db_ctx,
                               mem_ctx, certificate_principal,
                               ms_upn_check_attrs, &realm_dn, &msg);

      if (ret != 0) {
            talloc_free(mem_ctx);
            return ret;
      }

      orig_sid = samdb_result_dom_sid(mem_ctx, p->msg, "objectSid");
      target_sid = samdb_result_dom_sid(mem_ctx, msg, "objectSid");

      /* Consider these to be the same principal, even if by a different
       * name.  The easy and safe way to prove this is by SID
       * comparison */
      if (!(orig_sid && target_sid && dom_sid_equal(orig_sid, target_sid))) {
            talloc_free(mem_ctx);
            return KRB5_KDC_ERR_CLIENT_NAME_MISMATCH;
      }

      talloc_free(mem_ctx);
      return ret;
}


Generated by  Doxygen 1.6.0   Back to index