winbind: Keep "force_reauth" in invalidate_cm_connection
[kai/samba-autobuild/.git] / source3 / winbindd / winbindd_cm.c
index 17ede8c5cf2295b2e59b143c4d5baae02d639ba7..bf5a2b4d7b1c06b85c2af8728145451be66952e8 100644 (file)
 #include "messages.h"
 #include "auth/gensec/gensec.h"
 #include "../libcli/smb/smbXcli_base.h"
-#include "lib/param/loadparm.h"
+#include "libcli/auth/netlogon_creds_cli.h"
+#include "auth.h"
+#include "rpc_server/rpc_ncacn_np.h"
+#include "auth/credentials/credentials.h"
+#include "lib/param/param.h"
 
 #undef DBGC_CLASS
 #define DBGC_CLASS DBGC_WINBIND
@@ -91,10 +95,12 @@ struct dc_name_ip {
 extern struct winbindd_methods reconnect_methods;
 extern bool override_logfile;
 
-static NTSTATUS init_dc_connection_network(struct winbindd_domain *domain);
+static NTSTATUS init_dc_connection_network(struct winbindd_domain *domain, bool need_rw_dc);
 static void set_dc_type_and_flags( struct winbindd_domain *domain );
+static bool set_dc_type_and_flags_trustinfo( struct winbindd_domain *domain );
 static bool get_dcs(TALLOC_CTX *mem_ctx, struct winbindd_domain *domain,
-                   struct dc_name_ip **dcs, int *num_dcs);
+                   struct dc_name_ip **dcs, int *num_dcs,
+                   uint32_t request_flags);
 
 /****************************************************************
  Child failed to find DC's. Reschedule check.
@@ -173,7 +179,7 @@ static void msg_try_to_go_online(struct messaging_context *msg,
                           the offline handler if false. Bypasses online
                           check so always does network calls. */
 
-                       init_dc_connection_network(domain);
+                       init_dc_connection_network(domain, true);
                        break;
                }
        }
@@ -193,6 +199,7 @@ static bool fork_child_dc_connect(struct winbindd_domain *domain)
        pid_t parent_pid = getpid();
        char *lfile = NULL;
        NTSTATUS status;
+       bool ok;
 
        if (domain->dc_probe_pid != (pid_t)-1) {
                /*
@@ -217,10 +224,10 @@ static bool fork_child_dc_connect(struct winbindd_domain *domain)
 
        if (domain->dc_probe_pid != (pid_t)0) {
                /* Parent */
-               messaging_register(winbind_messaging_context(), NULL,
+               messaging_register(server_messaging_context(), NULL,
                                   MSG_WINBIND_TRY_TO_GO_ONLINE,
                                   msg_try_to_go_online);
-               messaging_register(winbind_messaging_context(), NULL,
+               messaging_register(server_messaging_context(), NULL,
                                   MSG_WINBIND_FAILED_TO_GO_ONLINE,
                                   msg_failed_to_go_online);
                return True;
@@ -241,7 +248,7 @@ static bool fork_child_dc_connect(struct winbindd_domain *domain)
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(1, ("winbindd_reinit_after_fork failed: %s\n",
                          nt_errstr(status)));
-               messaging_send_buf(winbind_messaging_context(),
+               messaging_send_buf(server_messaging_context(),
                                   pid_to_procid(parent_pid),
                                   MSG_WINBIND_FAILED_TO_GO_ONLINE,
                                   (const uint8_t *)domain->name,
@@ -250,10 +257,12 @@ static bool fork_child_dc_connect(struct winbindd_domain *domain)
        }
        SAFE_FREE(lfile);
 
+       setproctitle("dc-connect child");
+
        mem_ctx = talloc_init("fork_child_dc_connect");
        if (!mem_ctx) {
                DEBUG(0,("talloc_init failed.\n"));
-               messaging_send_buf(winbind_messaging_context(),
+               messaging_send_buf(server_messaging_context(),
                                   pid_to_procid(parent_pid),
                                   MSG_WINBIND_FAILED_TO_GO_ONLINE,
                                   (const uint8_t *)domain->name,
@@ -261,9 +270,11 @@ static bool fork_child_dc_connect(struct winbindd_domain *domain)
                _exit(1);
        }
 
-       if ((!get_dcs(mem_ctx, domain, &dcs, &num_dcs)) || (num_dcs == 0)) {
+       ok = get_dcs(mem_ctx, domain, &dcs, &num_dcs, 0);
+       TALLOC_FREE(mem_ctx);
+       if (!ok || (num_dcs == 0)) {
                /* Still offline ? Can't find DC's. */
-               messaging_send_buf(winbind_messaging_context(),
+               messaging_send_buf(server_messaging_context(),
                                   pid_to_procid(parent_pid),
                                   MSG_WINBIND_FAILED_TO_GO_ONLINE,
                                   (const uint8_t *)domain->name,
@@ -274,7 +285,7 @@ static bool fork_child_dc_connect(struct winbindd_domain *domain)
        /* We got a DC. Send a message to our parent to get it to
           try and do the same. */
 
-       messaging_send_buf(winbind_messaging_context(),
+       messaging_send_buf(server_messaging_context(),
                           pid_to_procid(parent_pid),
                           MSG_WINBIND_TRY_TO_GO_ONLINE,
                           (const uint8_t *)domain->name,
@@ -340,6 +351,46 @@ static void calc_new_online_timeout_check(struct winbindd_domain *domain)
        }
 }
 
+void winbind_msg_domain_offline(struct messaging_context *msg_ctx,
+                               void *private_data,
+                               uint32_t msg_type,
+                               struct server_id server_id,
+                               DATA_BLOB *data)
+{
+       const char *domain_name = (const char *)data->data;
+       struct winbindd_domain *domain;
+
+       domain = find_domain_from_name_noinit(domain_name);
+       if (domain == NULL) {
+               return;
+       }
+
+       domain->online = false;
+
+       DEBUG(10, ("Domain %s is marked as offline now.\n",
+                  domain_name));
+}
+
+void winbind_msg_domain_online(struct messaging_context *msg_ctx,
+                               void *private_data,
+                               uint32_t msg_type,
+                               struct server_id server_id,
+                               DATA_BLOB *data)
+{
+       const char *domain_name = (const char *)data->data;
+       struct winbindd_domain *domain;
+
+       domain = find_domain_from_name_noinit(domain_name);
+       if (domain == NULL) {
+               return;
+       }
+
+       domain->online = true;
+
+       DEBUG(10, ("Domain %s is marked as online now.\n",
+                  domain_name));
+}
+
 /****************************************************************
  Set domain offline and also add handler to put us back online
  if we detect a DC.
@@ -347,6 +398,8 @@ static void calc_new_online_timeout_check(struct winbindd_domain *domain)
 
 void set_domain_offline(struct winbindd_domain *domain)
 {
+       pid_t parent_pid = getppid();
+
        DEBUG(10,("set_domain_offline: called for domain %s\n",
                domain->name ));
 
@@ -380,7 +433,7 @@ void set_domain_offline(struct winbindd_domain *domain)
 
        calc_new_online_timeout_check(domain);
 
-       domain->check_online_event = tevent_add_timer(winbind_event_context(),
+       domain->check_online_event = tevent_add_timer(server_event_context(),
                                                NULL,
                                                timeval_current_ofs(domain->check_online_timeout,0),
                                                check_domain_online_handler,
@@ -394,6 +447,15 @@ void set_domain_offline(struct winbindd_domain *domain)
        DEBUG(10,("set_domain_offline: added event handler for domain %s\n",
                domain->name ));
 
+       /* Send a message to the parent that the domain is offline. */
+       if (parent_pid > 1 && !domain->internal) {
+               messaging_send_buf(server_messaging_context(),
+                                  pid_to_procid(parent_pid),
+                                  MSG_WINBIND_DOMAIN_OFFLINE,
+                                  (uint8_t *)domain->name,
+                                  strlen(domain->name) + 1);
+       }
+
        /* Send an offline message to the idmap child when our
           primary domain goes offline */
 
@@ -401,7 +463,7 @@ void set_domain_offline(struct winbindd_domain *domain)
                struct winbindd_child *idmap = idmap_child();
 
                if ( idmap->pid != 0 ) {
-                       messaging_send_buf(winbind_messaging_context(),
+                       messaging_send_buf(server_messaging_context(),
                                           pid_to_procid(idmap->pid), 
                                           MSG_WINBIND_OFFLINE, 
                                           (const uint8_t *)domain->name,
@@ -418,6 +480,8 @@ void set_domain_offline(struct winbindd_domain *domain)
 
 static void set_domain_online(struct winbindd_domain *domain)
 {
+       pid_t parent_pid = getppid();
+
        DEBUG(10,("set_domain_online: called for domain %s\n",
                domain->name ));
 
@@ -462,13 +526,22 @@ static void set_domain_online(struct winbindd_domain *domain)
        TALLOC_FREE(domain->check_online_event);
 
        /* Ensure we ignore any pending child messages. */
-       messaging_deregister(winbind_messaging_context(),
+       messaging_deregister(server_messaging_context(),
                             MSG_WINBIND_TRY_TO_GO_ONLINE, NULL);
-       messaging_deregister(winbind_messaging_context(),
+       messaging_deregister(server_messaging_context(),
                             MSG_WINBIND_FAILED_TO_GO_ONLINE, NULL);
 
        domain->online = True;
 
+       /* Send a message to the parent that the domain is online. */
+       if (parent_pid > 1 && !domain->internal) {
+               messaging_send_buf(server_messaging_context(),
+                                  pid_to_procid(parent_pid),
+                                  MSG_WINBIND_DOMAIN_ONLINE,
+                                  (uint8_t *)domain->name,
+                                  strlen(domain->name) + 1);
+       }
+
        /* Send an online message to the idmap child when our
           primary domain comes online */
 
@@ -476,7 +549,7 @@ static void set_domain_online(struct winbindd_domain *domain)
                struct winbindd_child *idmap = idmap_child();
 
                if ( idmap->pid != 0 ) {
-                       messaging_send_buf(winbind_messaging_context(),
+                       messaging_send_buf(server_messaging_context(),
                                           pid_to_procid(idmap->pid), 
                                           MSG_WINBIND_ONLINE, 
                                           (const uint8_t *)domain->name,
@@ -536,7 +609,7 @@ void set_domain_online_request(struct winbindd_domain *domain)
 
        TALLOC_FREE(domain->check_online_event);
 
-       domain->check_online_event = tevent_add_timer(winbind_event_context(),
+       domain->check_online_event = tevent_add_timer(server_event_context(),
                                                     NULL,
                                                     tev,
                                                     check_domain_online_handler,
@@ -601,9 +674,109 @@ static void cm_get_ipc_userpass(char **username, char **domain, char **password)
        }
 }
 
+static NTSTATUS cm_get_ipc_credentials(TALLOC_CTX *mem_ctx,
+                                      struct cli_credentials **_creds)
+{
+
+       TALLOC_CTX *frame = talloc_stackframe();
+       NTSTATUS status = NT_STATUS_INTERNAL_ERROR;
+       struct loadparm_context *lp_ctx;
+       char *username = NULL;
+       char *netbios_domain = NULL;
+       char *password = NULL;
+       struct cli_credentials *creds = NULL;
+       bool ok;
+
+       cm_get_ipc_userpass(&username, &netbios_domain, &password);
+
+       lp_ctx = loadparm_init_s3(frame, loadparm_s3_helpers());
+       if (lp_ctx == NULL) {
+               DEBUG(1, ("loadparm_init_s3 failed\n"));
+               status = NT_STATUS_INTERNAL_ERROR;
+               goto fail;
+       }
+
+       creds = cli_credentials_init(mem_ctx);
+       if (creds == NULL) {
+               status = NT_STATUS_NO_MEMORY;
+               goto fail;
+       }
+
+       cli_credentials_set_conf(creds, lp_ctx);
+       cli_credentials_set_kerberos_state(creds, CRED_DONT_USE_KERBEROS);
+
+       ok = cli_credentials_set_domain(creds, netbios_domain, CRED_SPECIFIED);
+       if (!ok) {
+               status = NT_STATUS_NO_MEMORY;
+               goto fail;
+       }
+
+       ok = cli_credentials_set_username(creds, username, CRED_SPECIFIED);
+       if (!ok) {
+               status = NT_STATUS_NO_MEMORY;
+               goto fail;
+       }
+
+       ok = cli_credentials_set_password(creds, password, CRED_SPECIFIED);
+       if (!ok) {
+               status = NT_STATUS_NO_MEMORY;
+               goto fail;
+       }
+
+       *_creds = creds;
+       creds = NULL;
+       status = NT_STATUS_OK;
+ fail:
+       TALLOC_FREE(creds);
+       SAFE_FREE(username);
+       SAFE_FREE(netbios_domain);
+       SAFE_FREE(password);
+       TALLOC_FREE(frame);
+       return status;
+}
+
+static bool cm_is_ipc_credentials(struct cli_credentials *creds)
+{
+       TALLOC_CTX *frame = talloc_stackframe();
+       char *ipc_account = NULL;
+       char *ipc_domain = NULL;
+       char *ipc_password = NULL;
+       const char *creds_account = NULL;
+       const char *creds_domain = NULL;
+       const char *creds_password = NULL;
+       bool ret = false;
+
+       cm_get_ipc_userpass(&ipc_account, &ipc_domain, &ipc_password);
+
+       creds_account = cli_credentials_get_username(creds);
+       creds_domain = cli_credentials_get_domain(creds);
+       creds_password = cli_credentials_get_password(creds);
+
+       if (!strequal(ipc_domain, creds_domain)) {
+               goto done;
+       }
+
+       if (!strequal(ipc_account, creds_account)) {
+               goto done;
+       }
+
+       if (!strcsequal(ipc_password, creds_password)) {
+               goto done;
+       }
+
+       ret = true;
+ done:
+       SAFE_FREE(ipc_account);
+       SAFE_FREE(ipc_domain);
+       SAFE_FREE(ipc_password);
+       TALLOC_FREE(frame);
+       return ret;
+}
+
 static bool get_dc_name_via_netlogon(struct winbindd_domain *domain,
                                     fstring dcname,
-                                    struct sockaddr_storage *dc_ss)
+                                    struct sockaddr_storage *dc_ss,
+                                    uint32_t request_flags)
 {
        struct winbindd_domain *our_domain = NULL;
        struct rpc_pipe_client *netlogon_pipe = NULL;
@@ -648,13 +821,17 @@ static bool get_dc_name_via_netlogon(struct winbindd_domain *domain,
        if (our_domain->active_directory) {
                struct netr_DsRGetDCNameInfo *domain_info = NULL;
 
+               /*
+                * TODO request flags are not respected in the server
+                * (and in some cases, like REQUIRE_PDC, causes an error)
+                */
                result = dcerpc_netr_DsRGetDCName(b,
                                                  mem_ctx,
                                                  our_domain->dcname,
                                                  domain->name,
                                                  NULL,
                                                  NULL,
-                                                 DS_RETURN_DNS_NAME,
+                                                 request_flags|DS_RETURN_DNS_NAME,
                                                  &domain_info,
                                                  &werr);
                if (NT_STATUS_IS_OK(result) && W_ERROR_IS_OK(werr)) {
@@ -728,61 +905,70 @@ static bool get_dc_name_via_netlogon(struct winbindd_domain *domain,
 /**
  * Helper function to assemble trust password and account name
  */
-static NTSTATUS get_trust_creds(const struct winbindd_domain *domain,
-                               char **machine_password,
-                               char **machine_account,
-                               char **machine_krb5_principal)
+static NTSTATUS get_trust_credentials(struct winbindd_domain *domain,
+                                     TALLOC_CTX *mem_ctx,
+                                     bool netlogon,
+                                     struct cli_credentials **_creds)
 {
-       const char *account_name;
-       const char *name = NULL;
+       const struct winbindd_domain *creds_domain = NULL;
+       struct cli_credentials *creds;
+       NTSTATUS status;
+       bool force_machine_account = false;
 
        /* If we are a DC and this is not our own domain */
 
-       if (IS_DC) {
-               name = domain->name;
-       } else {
-               struct winbindd_domain *our_domain = find_our_domain();
-
-               if (!our_domain)
-                       return NT_STATUS_INVALID_SERVER_STATE;          
-
-               name = our_domain->name;                
-       }       
-
-       if (!get_trust_pw_clear(name, machine_password,
-                               &account_name, NULL))
-       {
-               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
+       if (!domain->active_directory) {
+               if (!netlogon) {
+                       /*
+                        * For non active directory domains
+                        * we can only use NTLMSSP for SMB.
+                        *
+                        * But the trust account is not allowed
+                        * to use SMB with NTLMSSP.
+                        */
+                       force_machine_account = true;
+               }
        }
 
-       if ((machine_account != NULL) &&
-           (asprintf(machine_account, "%s$", account_name) == -1))
-       {
-               return NT_STATUS_NO_MEMORY;
+       if (IS_DC && !force_machine_account) {
+               creds_domain = domain;
+       } else {
+               creds_domain = find_our_domain();
+               if (creds_domain == NULL) {
+                       return NT_STATUS_INVALID_SERVER_STATE;
+               }
        }
 
-       /* For now assume our machine account only exists in our domain */
+       status = pdb_get_trust_credentials(creds_domain->name,
+                                          creds_domain->alt_name,
+                                          mem_ctx,
+                                          &creds);
+       if (!NT_STATUS_IS_OK(status)) {
+               goto ipc_fallback;
+       }
 
-       if (machine_krb5_principal != NULL)
-       {
-               struct winbindd_domain *our_domain = find_our_domain();
+       if (creds_domain != domain) {
+               /*
+                * We can only use schannel against a direct trust
+                */
+               cli_credentials_set_secure_channel_type(creds,
+                                                       SEC_CHAN_NULL);
+       }
 
-               if (!our_domain) {
-                       return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;                       
-               }
+       *_creds = creds;
+       return NT_STATUS_OK;
 
-               if (asprintf(machine_krb5_principal, "%s$@%s",
-                            account_name, our_domain->alt_name) == -1)
-               {
-                       return NT_STATUS_NO_MEMORY;
-               }
+ ipc_fallback:
+       if (netlogon) {
+               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
+       }
 
-               if (!strupper_m(*machine_krb5_principal)) {
-                       SAFE_FREE(*machine_krb5_principal);
-                       return NT_STATUS_INVALID_PARAMETER;
-               }
+       status = cm_get_ipc_credentials(mem_ctx, &creds);
+       if (!NT_STATUS_IS_OK(status)) {
+               return status;
        }
 
+       *_creds = creds;
        return NT_STATUS_OK;
 }
 
@@ -791,26 +977,72 @@ static NTSTATUS get_trust_creds(const struct winbindd_domain *domain,
  to the pipe.
 ************************************************************************/
 
-static NTSTATUS cm_prepare_connection(const struct winbindd_domain *domain,
+static NTSTATUS cm_prepare_connection(struct winbindd_domain *domain,
                                      const int sockfd,
                                      const char *controller,
                                      struct cli_state **cli,
                                      bool *retry)
 {
-       bool try_spnego = false;
        bool try_ipc_auth = false;
-       char *machine_password = NULL;
-       char *machine_krb5_principal = NULL;
-       char *machine_account = NULL;
-       char *ipc_username = NULL;
-       char *ipc_domain = NULL;
-       char *ipc_password = NULL;
+       const char *machine_principal = NULL;
+       const char *machine_realm = NULL;
+       const char *machine_account = NULL;
+       const char *machine_domain = NULL;
        int flags = 0;
-       uint16_t sec_mode = 0;
+       struct cli_credentials *creds = NULL;
 
        struct named_mutex *mutex;
 
        NTSTATUS result = NT_STATUS_UNSUCCESSFUL;
+       NTSTATUS tmp_status;
+       NTSTATUS tcon_status = NT_STATUS_NETWORK_NAME_DELETED;
+
+       enum smb_signing_setting smb_sign_client_connections = lp_client_ipc_signing();
+
+       if (IS_AD_DC) {
+               if (domain->secure_channel_type == SEC_CHAN_NULL) {
+                       /*
+                        * Make sure we don't even try to
+                        * connect to a foreign domain
+                        * without a direct outbound trust.
+                        */
+                       return NT_STATUS_NO_TRUST_LSA_SECRET;
+               }
+
+               /*
+                * As AD DC we only use netlogon and lsa
+                * using schannel over an anonymous transport
+                * (ncacn_ip_tcp or ncacn_np).
+                *
+                * Currently we always establish the SMB connection,
+                * even if we don't use it, because we later use ncacn_ip_tcp.
+                *
+                * As we won't use the SMB connection there's no
+                * need to try kerberos. And NT4 domains expect
+                * an anonymous IPC$ connection anyway.
+                */
+               smb_sign_client_connections = SMB_SIGNING_OFF;
+       }
+
+       if (smb_sign_client_connections == SMB_SIGNING_DEFAULT) {
+               /*
+                * If we are connecting to our own AD domain, require
+                * smb signing to disrupt MITM attacks
+                */
+               if (domain->primary && lp_security() == SEC_ADS) {
+                       smb_sign_client_connections = SMB_SIGNING_REQUIRED;
+               /*
+                * If we are in or are an AD domain and connecting to another
+                * AD domain in our forest
+                * then require smb signing to disrupt MITM attacks
+                */
+               } else if ((lp_security() == SEC_ADS)
+                          && domain->active_directory
+                          && (domain->domain_trust_attribs
+                              & LSA_TRUST_ATTRIBUTE_WITHIN_FOREST)) {
+                       smb_sign_client_connections = SMB_SIGNING_REQUIRED;
+               }
+       }
 
        DEBUG(10,("cm_prepare_connection: connecting to DC %s for domain %s\n",
                controller, domain->name ));
@@ -827,11 +1059,8 @@ static NTSTATUS cm_prepare_connection(const struct winbindd_domain *domain,
                goto done;
        }
 
-       flags |= CLI_FULL_CONNECTION_USE_KERBEROS;
-
-       *cli = cli_state_create(NULL, sockfd,
-                               controller, domain->alt_name,
-                               SMB_SIGNING_DEFAULT, flags);
+       *cli = cli_state_create(NULL, sockfd, controller,
+                               smb_sign_client_connections, flags);
        if (*cli == NULL) {
                close(sockfd);
                DEBUG(1, ("Could not cli_initialize\n"));
@@ -841,9 +1070,11 @@ static NTSTATUS cm_prepare_connection(const struct winbindd_domain *domain,
 
        cli_set_timeout(*cli, 10000); /* 10 seconds */
 
+       set_socket_options(sockfd, lp_socket_options());
+
        result = smbXcli_negprot((*cli)->conn, (*cli)->timeout,
-                                lp_cli_minprotocol(),
-                                lp_cli_maxprotocol());
+                                lp_client_ipc_min_protocol(),
+                                lp_client_ipc_max_protocol());
 
        if (!NT_STATUS_IS_OK(result)) {
                DEBUG(1, ("cli_negprot failed: %s\n", nt_errstr(result)));
@@ -852,143 +1083,180 @@ static NTSTATUS cm_prepare_connection(const struct winbindd_domain *domain,
 
        if (smbXcli_conn_protocol((*cli)->conn) >= PROTOCOL_NT1 &&
            smb1cli_conn_capabilities((*cli)->conn) & CAP_EXTENDED_SECURITY) {
-               try_spnego = true;
+               try_ipc_auth = true;
        } else if (smbXcli_conn_protocol((*cli)->conn) >= PROTOCOL_SMB2_02) {
-               try_spnego = true;
+               try_ipc_auth = true;
+       } else if (smb_sign_client_connections == SMB_SIGNING_REQUIRED) {
+               /*
+                * If we are forcing on SMB signing, then we must
+                * require authentication unless this is a one-way
+                * trust, and we have no stored user/password
+                */
+               try_ipc_auth = true;
        }
 
-       if (!is_dc_trusted_domain_situation(domain->name) && try_spnego) {
-               result = get_trust_creds(domain, &machine_password,
-                                        &machine_account,
-                                        &machine_krb5_principal);
+       if (IS_AD_DC) {
+               /*
+                * As AD DC we only use netlogon and lsa
+                * using schannel over an anonymous transport
+                * (ncacn_ip_tcp or ncacn_np).
+                *
+                * Currently we always establish the SMB connection,
+                * even if we don't use it, because we later use ncacn_ip_tcp.
+                *
+                * As we won't use the SMB connection there's no
+                * need to try kerberos. And NT4 domains expect
+                * an anonymous IPC$ connection anyway.
+                */
+               try_ipc_auth = false;
+       }
+
+       if (try_ipc_auth) {
+               result = get_trust_credentials(domain, talloc_tos(), false, &creds);
                if (!NT_STATUS_IS_OK(result)) {
-                       goto anon_fallback;
+                       DEBUG(1, ("get_trust_credentials(%s) failed: %s\n",
+                                 domain->name, nt_errstr(result)));
+                       goto done;
+               }
+       } else {
+               /*
+                * Without SPNEGO or NTLMSSP (perhaps via SMB2) we
+                * would try and authentication with our machine
+                * account password and fail.  This is very rare in
+                * the modern world however
+                */
+               creds = cli_credentials_init_anon(talloc_tos());
+               if (creds == NULL) {
+                       result = NT_STATUS_NO_MEMORY;
+                       DEBUG(1, ("cli_credentials_init_anon(%s) failed: %s\n",
+                                 domain->name, nt_errstr(result)));
+                       goto done;
                }
+       }
 
-               if (lp_security() == SEC_ADS) {
+       machine_principal = cli_credentials_get_principal(creds,
+                                                       talloc_tos());
+       machine_realm = cli_credentials_get_realm(creds);
+       machine_account = cli_credentials_get_username(creds);
+       machine_domain = cli_credentials_get_domain(creds);
 
-                       /* Try a krb5 session */
+       DEBUG(5, ("connecting to %s (%s, %s) with account [%s\\%s] principal "
+                 "[%s] and realm [%s]\n",
+                 controller, domain->name, domain->alt_name,
+                 machine_domain, machine_account,
+                 machine_principal, machine_realm));
 
-                       (*cli)->use_kerberos = True;
-                       DEBUG(5, ("connecting to %s from %s with kerberos principal "
-                                 "[%s] and realm [%s]\n", controller, lp_netbios_name(),
-                                 machine_krb5_principal, domain->alt_name));
+       if (cli_credentials_is_anonymous(creds)) {
+               goto anon_fallback;
+       }
 
-                       winbindd_set_locator_kdc_envs(domain);
+       winbindd_set_locator_kdc_envs(domain);
 
-                       result = cli_session_setup(*cli,
-                                                  machine_krb5_principal,
-                                                  machine_password,
-                                                  strlen(machine_password)+1,
-                                                  machine_password,
-                                                  strlen(machine_password)+1,
-                                                  lp_workgroup());
+       result = cli_session_setup_creds(*cli, creds);
+       if (NT_STATUS_IS_OK(result)) {
+               goto session_setup_done;
+       }
 
-                       if (!NT_STATUS_IS_OK(result)) {
-                               DEBUG(4,("failed kerberos session setup with %s\n",
-                                       nt_errstr(result)));
-                       }
+       DEBUG(1, ("authenticated session setup to %s using %s failed with %s\n",
+                 controller,
+                 cli_credentials_get_unparsed_name(creds, talloc_tos()),
+                 nt_errstr(result)));
 
-                       if (NT_STATUS_IS_OK(result)) {
-                               /* Ensure creds are stored for NTLMSSP authenticated pipe access. */
-                               result = cli_init_creds(*cli, machine_account, lp_workgroup(), machine_password);
-                               if (!NT_STATUS_IS_OK(result)) {
-                                       goto done;
-                               }
-                               goto session_setup_done;
-                       }
+       /*
+        * If we are not going to validiate the conneciton
+        * with SMB signing, then allow us to fall back to
+        * anonymous
+        */
+       if (NT_STATUS_EQUAL(result, NT_STATUS_NOLOGON_WORKSTATION_TRUST_ACCOUNT)
+           || NT_STATUS_EQUAL(result, NT_STATUS_TRUSTED_DOMAIN_FAILURE)
+           || NT_STATUS_EQUAL(result, NT_STATUS_INVALID_ACCOUNT_NAME)
+           || NT_STATUS_EQUAL(result, NT_STATUS_NO_LOGON_SERVERS)
+           || NT_STATUS_EQUAL(result, NT_STATUS_LOGON_FAILURE))
+       {
+               if (!cm_is_ipc_credentials(creds)) {
+                       goto ipc_fallback;
                }
 
-               /* Fall back to non-kerberos session setup using NTLMSSP SPNEGO with the machine account. */
-               (*cli)->use_kerberos = False;
-
-               DEBUG(5, ("connecting to %s from %s with username "
-                         "[%s]\\[%s]\n",  controller, lp_netbios_name(),
-                         lp_workgroup(), machine_account));
-
-               result = cli_session_setup(*cli,
-                                          machine_account,
-                                          machine_password,
-                                          strlen(machine_password)+1,
-                                          machine_password,
-                                          strlen(machine_password)+1,
-                                          lp_workgroup());
-               if (!NT_STATUS_IS_OK(result)) {
-                       DEBUG(4, ("authenticated session setup failed with %s\n",
-                               nt_errstr(result)));
+               if (smb_sign_client_connections == SMB_SIGNING_REQUIRED) {
+                       goto done;
                }
 
-               if (NT_STATUS_IS_OK(result)) {
-                       /* Ensure creds are stored for NTLMSSP authenticated pipe access. */
-                       result = cli_init_creds(*cli, machine_account, lp_workgroup(), machine_password);
-                       if (!NT_STATUS_IS_OK(result)) {
-                               goto done;
-                       }
-                       goto session_setup_done;
-               }
+               goto anon_fallback;
        }
 
-       /* Fall back to non-kerberos session setup with auth_user */
-
-       (*cli)->use_kerberos = False;
-
-       cm_get_ipc_userpass(&ipc_username, &ipc_domain, &ipc_password);
+       goto done;
 
-       sec_mode = smb1cli_conn_server_security_mode((*cli)->conn);
+ ipc_fallback:
+       TALLOC_FREE(creds);
+       tmp_status = cm_get_ipc_credentials(talloc_tos(), &creds);
+       if (!NT_STATUS_IS_OK(tmp_status)) {
+               result = tmp_status;
+               goto done;
+       }
 
-       try_ipc_auth = false;
-       if (try_spnego) {
-               try_ipc_auth = true;
-       } else if (sec_mode & NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) {
-               try_ipc_auth = true;
+       if (cli_credentials_is_anonymous(creds)) {
+               goto anon_fallback;
        }
 
-       if (try_ipc_auth && (strlen(ipc_username) > 0)) {
+       machine_account = cli_credentials_get_username(creds);
+       machine_domain = cli_credentials_get_domain(creds);
 
-               /* Only try authenticated if we have a username */
+       DEBUG(5, ("connecting to %s from %s using NTLMSSP with username "
+                 "[%s]\\[%s]\n",  controller, lp_netbios_name(),
+                 machine_domain, machine_account));
+
+       result = cli_session_setup_creds(*cli, creds);
+       if (NT_STATUS_IS_OK(result)) {
+               goto session_setup_done;
+       }
 
-               DEBUG(5, ("connecting to %s from %s with username "
-                         "[%s]\\[%s]\n",  controller, lp_netbios_name(),
-                         ipc_domain, ipc_username));
+       DEBUG(1, ("authenticated session setup to %s using %s failed with %s\n",
+                 controller,
+                 cli_credentials_get_unparsed_name(creds, talloc_tos()),
+                 nt_errstr(result)));
 
-               if (NT_STATUS_IS_OK(cli_session_setup(
-                                           *cli, ipc_username,
-                                           ipc_password, strlen(ipc_password)+1,
-                                           ipc_password, strlen(ipc_password)+1,
-                                           ipc_domain))) {
-                       /* Successful logon with given username. */
-                       result = cli_init_creds(*cli, ipc_username, ipc_domain, ipc_password);
-                       if (!NT_STATUS_IS_OK(result)) {
-                               goto done;
-                       }
-                       goto session_setup_done;
-               } else {
-                       DEBUG(4, ("authenticated session setup with user %s\\%s failed.\n",
-                               ipc_domain, ipc_username ));
-               }
+       /*
+        * If we are not going to validiate the conneciton
+        * with SMB signing, then allow us to fall back to
+        * anonymous
+        */
+       if (NT_STATUS_EQUAL(result, NT_STATUS_NOLOGON_WORKSTATION_TRUST_ACCOUNT)
+           || NT_STATUS_EQUAL(result, NT_STATUS_TRUSTED_DOMAIN_FAILURE)
+           || NT_STATUS_EQUAL(result, NT_STATUS_INVALID_ACCOUNT_NAME)
+           || NT_STATUS_EQUAL(result, NT_STATUS_NO_LOGON_SERVERS)
+           || NT_STATUS_EQUAL(result, NT_STATUS_LOGON_FAILURE))
+       {
+               goto anon_fallback;
        }
 
+       goto done;
+
  anon_fallback:
+       TALLOC_FREE(creds);
+
+       if (smb_sign_client_connections == SMB_SIGNING_REQUIRED) {
+               goto done;
+       }
 
        /* Fall back to anonymous connection, this might fail later */
-       DEBUG(10,("cm_prepare_connection: falling back to anonymous "
+       DEBUG(5,("cm_prepare_connection: falling back to anonymous "
                "connection for DC %s\n",
                controller ));
 
-       result = cli_session_setup(*cli, "", NULL, 0, NULL, 0, "");
+       result = cli_session_setup_anon(*cli);
        if (NT_STATUS_IS_OK(result)) {
                DEBUG(5, ("Connected anonymously\n"));
-               result = cli_init_creds(*cli, "", "", "");
-               if (!NT_STATUS_IS_OK(result)) {
-                       goto done;
-               }
                goto session_setup_done;
        }
 
+       DEBUG(1, ("anonymous session setup to %s failed with %s\n",
+                 controller, nt_errstr(result)));
+
        /* We can't session setup */
        goto done;
 
  session_setup_done:
+       TALLOC_FREE(creds);
 
        /*
         * This should be a short term hack until
@@ -1001,48 +1269,38 @@ static NTSTATUS cm_prepare_connection(const struct winbindd_domain *domain,
                smbXcli_session_set_disconnect_expired((*cli)->smb2.session);
        }
 
+       result = cli_tree_connect(*cli, "IPC$", "IPC", NULL);
+       if (!NT_STATUS_IS_OK(result)) {
+               DEBUG(1,("failed tcon_X with %s\n", nt_errstr(result)));
+               goto done;
+       }
+       tcon_status = result;
+
        /* cache the server name for later connections */
 
        saf_store(domain->name, controller);
-       if (domain->alt_name && (*cli)->use_kerberos) {
+       if (domain->alt_name) {
                saf_store(domain->alt_name, controller);
        }
 
        winbindd_set_locator_kdc_envs(domain);
 
-       result = cli_tree_connect(*cli, "IPC$", "IPC", "", 0);
-
-       if (!NT_STATUS_IS_OK(result)) {
-               DEBUG(1,("failed tcon_X with %s\n", nt_errstr(result)));
-               goto done;
-       }
-
        TALLOC_FREE(mutex);
        *retry = False;
 
-       /* set the domain if empty; needed for schannel connections */
-       if ( !(*cli)->domain[0] ) {
-               result = cli_set_domain((*cli), domain->name);
-               if (!NT_STATUS_IS_OK(result)) {
-                       SAFE_FREE(ipc_username);
-                       SAFE_FREE(ipc_domain);
-                       SAFE_FREE(ipc_password);
-                       return result;
-               }
-       }
-
        result = NT_STATUS_OK;
 
  done:
        TALLOC_FREE(mutex);
-       SAFE_FREE(machine_account);
-       SAFE_FREE(machine_password);
-       SAFE_FREE(machine_krb5_principal);
-       SAFE_FREE(ipc_username);
-       SAFE_FREE(ipc_domain);
-       SAFE_FREE(ipc_password);
+       TALLOC_FREE(creds);
+
+       if (NT_STATUS_IS_OK(result)) {
+               result = tcon_status;
+       }
 
        if (!NT_STATUS_IS_OK(result)) {
+               DEBUG(1, ("Failed to prepare SMB connection to %s: %s\n",
+                         controller, nt_errstr(result)));
                winbind_add_failed_connection_entry(domain, controller, result);
                if ((*cli) != NULL) {
                        cli_shutdown(*cli);
@@ -1098,7 +1356,7 @@ static bool add_one_dc_unique(TALLOC_CTX *mem_ctx, const char *domain_name,
 }
 
 static bool add_sockaddr_to_array(TALLOC_CTX *mem_ctx,
-                                 struct sockaddr_storage *pss, uint16 port,
+                                 struct sockaddr_storage *pss, uint16_t port,
                                  struct sockaddr_storage **addrs, int *num)
 {
        *addrs = talloc_realloc(mem_ctx, *addrs, struct sockaddr_storage, (*num)+1);
@@ -1117,19 +1375,22 @@ static bool add_sockaddr_to_array(TALLOC_CTX *mem_ctx,
 
 /*******************************************************************
  convert an ip to a name
+ For an AD Domain, it checks the requirements of the request flags.
 *******************************************************************/
 
-static bool dcip_to_name(TALLOC_CTX *mem_ctx,
-               const struct winbindd_domain *domain,
-               struct sockaddr_storage *pss,
-               char **name)
+static bool dcip_check_name(TALLOC_CTX *mem_ctx,
+                           const struct winbindd_domain *domain,
+                           struct sockaddr_storage *pss,
+                           char **name, uint32_t request_flags)
 {
        struct ip_service ip_list;
        uint32_t nt_version = NETLOGON_NT_VERSION_1;
        NTSTATUS status;
        const char *dc_name;
        fstring nbtname;
-
+#ifdef HAVE_ADS
+       bool is_ad_domain = false;
+#endif
        ip_list.ss = *pss;
        ip_list.port = 0;
 
@@ -1137,7 +1398,13 @@ static bool dcip_to_name(TALLOC_CTX *mem_ctx,
        /* For active directory servers, try to get the ldap server name.
           None of these failures should be considered critical for now */
 
-       if (lp_security() == SEC_ADS) {
+       if ((lp_security() == SEC_ADS) && (domain->alt_name != NULL)) {
+               is_ad_domain = true;
+       } else if (lp_server_role() == ROLE_ACTIVE_DIRECTORY_DC) {
+               is_ad_domain = domain->active_directory;
+       }
+
+       if (is_ad_domain) {
                ADS_STRUCT *ads;
                ADS_STATUS ads_status;
                char addr[INET6_ADDRSTRLEN];
@@ -1146,6 +1413,8 @@ static bool dcip_to_name(TALLOC_CTX *mem_ctx,
 
                ads = ads_init(domain->alt_name, domain->name, addr);
                ads->auth.flags |= ADS_AUTH_NO_BIND;
+               ads->config.flags |= request_flags;
+               ads->server.no_fallback = true;
 
                ads_status = ads_connect(ads);
                if (ADS_ERR_OK(ads_status)) {
@@ -1157,7 +1426,7 @@ static bool dcip_to_name(TALLOC_CTX *mem_ctx,
                        }
                        namecache_store(*name, 0x20, 1, &ip_list);
 
-                       DEBUG(10,("dcip_to_name: flags = 0x%x\n", (unsigned int)ads->config.flags));
+                       DEBUG(10,("dcip_check_name: flags = 0x%x\n", (unsigned int)ads->config.flags));
 
                        if (domain->primary && (ads->config.flags & NBT_SERVER_KDC)) {
                                if (ads_closest_dc(ads)) {
@@ -1170,8 +1439,7 @@ static bool dcip_to_name(TALLOC_CTX *mem_ctx,
                                        create_local_private_krb5_conf_for_domain(domain->alt_name,
                                                                        domain->name,
                                                                        sitename,
-                                                                       pss,
-                                                                       *name);
+                                                                       pss);
 
                                        TALLOC_FREE(sitename);
                                } else {
@@ -1179,8 +1447,7 @@ static bool dcip_to_name(TALLOC_CTX *mem_ctx,
                                        create_local_private_krb5_conf_for_domain(domain->alt_name,
                                                                        domain->name,
                                                                        NULL,
-                                                                       pss,
-                                                                       *name);
+                                                                       pss);
                                }
                                winbindd_set_locator_kdc_envs(domain);
 
@@ -1198,7 +1465,7 @@ static bool dcip_to_name(TALLOC_CTX *mem_ctx,
        }
 #endif
 
-       status = nbt_getdc(winbind_messaging_context(), 10, pss, domain->name,
+       status = nbt_getdc(server_messaging_context(), 10, pss, domain->name,
                           &domain->sid, nt_version, mem_ctx, &nt_version,
                           &dc_name, NULL);
        if (NT_STATUS_IS_OK(status)) {
@@ -1240,7 +1507,8 @@ static bool dcip_to_name(TALLOC_CTX *mem_ctx,
 *******************************************************************/
 
 static bool get_dcs(TALLOC_CTX *mem_ctx, struct winbindd_domain *domain,
-                   struct dc_name_ip **dcs, int *num_dcs)
+                   struct dc_name_ip **dcs, int *num_dcs,
+                   uint32_t request_flags)
 {
        fstring dcname;
        struct  sockaddr_storage ss;
@@ -1254,7 +1522,7 @@ static bool get_dcs(TALLOC_CTX *mem_ctx, struct winbindd_domain *domain,
 
        /* If not our domain, get the preferred DC, by asking our primary DC */
        if ( !is_our_domain
-               && get_dc_name_via_netlogon(domain, dcname, &ss)
+               && get_dc_name_via_netlogon(domain, dcname, &ss, request_flags)
                && add_one_dc_unique(mem_ctx, domain->name, dcname, &ss, dcs,
                       num_dcs) )
        {
@@ -1265,7 +1533,7 @@ static bool get_dcs(TALLOC_CTX *mem_ctx, struct winbindd_domain *domain,
                return True;
        }
 
-       if (sec == SEC_ADS) {
+       if ((sec == SEC_ADS) && (domain->alt_name != NULL)) {
                char *sitename = NULL;
 
                /* We need to make sure we know the local site before
@@ -1371,13 +1639,14 @@ static bool get_dcs(TALLOC_CTX *mem_ctx, struct winbindd_domain *domain,
 
 static bool find_new_dc(TALLOC_CTX *mem_ctx,
                        struct winbindd_domain *domain,
-                       char **dcname, struct sockaddr_storage *pss, int *fd)
+                       char **dcname, struct sockaddr_storage *pss, int *fd,
+                       uint32_t request_flags)
 {
        struct dc_name_ip *dcs = NULL;
        int num_dcs = 0;
 
        const char **dcnames = NULL;
-       int num_dcnames = 0;
+       size_t num_dcnames = 0;
 
        struct sockaddr_storage *addrs = NULL;
        int num_addrs = 0;
@@ -1390,7 +1659,7 @@ static bool find_new_dc(TALLOC_CTX *mem_ctx,
        *fd = -1;
 
  again:
-       if (!get_dcs(mem_ctx, domain, &dcs, &num_dcs) || (num_dcs == 0))
+       if (!get_dcs(mem_ctx, domain, &dcs, &num_dcs, request_flags) || (num_dcs == 0))
                return False;
 
        for (i=0; i<num_dcs; i++) {
@@ -1438,7 +1707,7 @@ static bool find_new_dc(TALLOC_CTX *mem_ctx,
        }
 
        /* Try to figure out the name */
-       if (dcip_to_name(mem_ctx, domain, pss, dcname)) {
+       if (dcip_check_name(mem_ctx, domain, pss, dcname, request_flags)) {
                return True;
        }
 
@@ -1503,7 +1772,8 @@ bool fetch_current_dc_from_gencache(TALLOC_CTX *mem_ctx,
                                    const char *domain_name,
                                    char **p_dc_name, char **p_dc_ip)
 {
-       char *key, *value, *p;
+       char *key, *p;
+       char *value = NULL;
        bool ret = false;
        char *dc_name = NULL;
        char *dc_ip = NULL;
@@ -1512,7 +1782,7 @@ bool fetch_current_dc_from_gencache(TALLOC_CTX *mem_ctx,
        if (key == NULL) {
                goto done;
        }
-       if (!gencache_get(key, NULL, &value, NULL)) {
+       if (!gencache_get(key, mem_ctx, &value, NULL)) {
                goto done;
        }
        p = strchr(value, ' ');
@@ -1541,16 +1811,62 @@ done:
        TALLOC_FREE(dc_name);
        TALLOC_FREE(dc_ip);
        TALLOC_FREE(key);
+       TALLOC_FREE(value);
        return ret;
 }
 
+NTSTATUS wb_open_internal_pipe(TALLOC_CTX *mem_ctx,
+                              const struct ndr_interface_table *table,
+                              struct rpc_pipe_client **ret_pipe)
+{
+       struct rpc_pipe_client *cli = NULL;
+       const struct auth_session_info *session_info;
+       NTSTATUS status = NT_STATUS_UNSUCCESSFUL;
+
+
+       session_info = get_session_info_system();
+       SMB_ASSERT(session_info != NULL);
+
+       /* create a connection to the specified pipe */
+       if (lp_parm_bool(-1, "winbindd", "use external pipes", false)) {
+               status = rpc_pipe_open_interface(mem_ctx,
+                                                table,
+                                                session_info,
+                                                NULL,
+                                                NULL,
+                                                server_messaging_context(),
+                                                &cli);
+       } else {
+               status = rpc_pipe_open_internal(mem_ctx,
+                                               table,
+                                               session_info,
+                                               NULL,
+                                               NULL,
+                                               server_messaging_context(),
+                                               &cli);
+       }
+       if (!NT_STATUS_IS_OK(status)) {
+               DEBUG(0, ("open_internal_pipe: Could not connect to %s pipe: %s\n",
+                         table->name, nt_errstr(status)));
+               return status;
+       }
+
+       if (ret_pipe) {
+               *ret_pipe = cli;
+       }
+
+       return NT_STATUS_OK;
+}
+
 static NTSTATUS cm_open_connection(struct winbindd_domain *domain,
-                                  struct winbindd_cm_conn *new_conn)
+                                  struct winbindd_cm_conn *new_conn,
+                                  bool need_rw_dc)
 {
        TALLOC_CTX *mem_ctx;
        NTSTATUS result;
        char *saf_servername;
        int retries;
+       uint32_t request_flags = need_rw_dc ? DS_WRITABLE_REQUIRED : 0;
 
        if ((mem_ctx = talloc_init("cm_open_connection")) == NULL) {
                set_domain_offline(domain);
@@ -1566,39 +1882,39 @@ static NTSTATUS cm_open_connection(struct winbindd_domain *domain,
           before talking to it. It going down may have
           triggered the reconnection. */
 
-       if ( saf_servername && NT_STATUS_IS_OK(check_negative_conn_cache( domain->name, saf_servername))) {
+       if (saf_servername && NT_STATUS_IS_OK(check_negative_conn_cache(domain->name, saf_servername))) {
+               struct sockaddr_storage ss;
+               char *dcname = NULL;
+               bool resolved = true;
 
-               DEBUG(10,("cm_open_connection: saf_servername is '%s' for domain %s\n",
-                       saf_servername, domain->name ));
+               DEBUG(10, ("cm_open_connection: saf_servername is '%s' for domain %s\n",
+                          saf_servername, domain->name));
 
                /* convert an ip address to a name */
-               if (is_ipaddress( saf_servername ) ) {
-                       char *dcname = NULL;
-                       struct sockaddr_storage ss;
-
+               if (is_ipaddress(saf_servername)) {
                        if (!interpret_string_addr(&ss, saf_servername,
-                                               AI_NUMERICHOST)) {
+                                                  AI_NUMERICHOST)) {
                                TALLOC_FREE(mem_ctx);
                                return NT_STATUS_UNSUCCESSFUL;
                        }
-                       if (dcip_to_name(mem_ctx, domain, &ss, &dcname)) {
-                               domain->dcname = talloc_strdup(domain,
-                                                              dcname);
-                               if (domain->dcname == NULL) {
-                                       TALLOC_FREE(mem_ctx);
-                                       return NT_STATUS_NO_MEMORY;
-                               }
-                       } else {
-                               winbind_add_failed_connection_entry(
-                                       domain, saf_servername,
-                                       NT_STATUS_UNSUCCESSFUL);
-                       }
                } else {
-                       domain->dcname = talloc_strdup(domain, saf_servername);
+                       if (!resolve_name(saf_servername, &ss, 0x20, true)) {
+                               resolved = false;
+                       }
+               }
+
+               if (resolved && dcip_check_name(mem_ctx, domain, &ss, &dcname, request_flags)) {
+                       domain->dcname = talloc_strdup(domain,
+                                                      dcname);
                        if (domain->dcname == NULL) {
                                TALLOC_FREE(mem_ctx);
                                return NT_STATUS_NO_MEMORY;
                        }
+
+                       domain->dcaddr = ss;
+               } else {
+                       winbind_add_failed_connection_entry(domain, saf_servername,
+                                                           NT_STATUS_UNSUCCESSFUL);
                }
        }
 
@@ -1609,12 +1925,12 @@ static NTSTATUS cm_open_connection(struct winbindd_domain *domain,
 
                result = NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND;
 
-               DEBUG(10,("cm_open_connection: dcname is '%s' for domain %s\n",
-                       domain->dcname ? domain->dcname : "", domain->name ));
+               DEBUG(10, ("cm_open_connection: dcname is '%s' for domain %s\n",
+                          domain->dcname ? domain->dcname : "", domain->name));
 
-               if (domain->dcname != NULL
-                       && NT_STATUS_IS_OK(check_negative_conn_cache( domain->name, domain->dcname))
-                       && (resolve_name(domain->dcname, &domain->dcaddr, 0x20, true)))
+               if (domain->dcname != NULL &&
+                   NT_STATUS_IS_OK(check_negative_conn_cache(domain->name,
+                                                             domain->dcname)))
                {
                        NTSTATUS status;
 
@@ -1627,7 +1943,7 @@ static NTSTATUS cm_open_connection(struct winbindd_domain *domain,
                }
 
                if ((fd == -1) &&
-                   !find_new_dc(mem_ctx, domain, &dcname, &domain->dcaddr, &fd))
+                   !find_new_dc(mem_ctx, domain, &dcname, &domain->dcaddr, &fd, request_flags))
                {
                        /* This is the one place where we will
                           set the global winbindd offline state
@@ -1660,6 +1976,7 @@ static NTSTATUS cm_open_connection(struct winbindd_domain *domain,
        }
 
        if (NT_STATUS_IS_OK(result)) {
+               bool seal_pipes = true;
 
                winbindd_set_locator_kdc_envs(domain);
 
@@ -1679,6 +1996,17 @@ static NTSTATUS cm_open_connection(struct winbindd_domain *domain,
                 */
                store_current_dc_in_gencache(domain->name, domain->dcname,
                                             new_conn->cli);
+
+               seal_pipes = lp_winbind_sealed_pipes();
+               seal_pipes = lp_parm_bool(-1, "winbind sealed pipes",
+                                         domain->name,
+                                         seal_pipes);
+
+               if (seal_pipes) {
+                       new_conn->auth_level = DCERPC_AUTH_LEVEL_PRIVACY;
+               } else {
+                       new_conn->auth_level = DCERPC_AUTH_LEVEL_INTEGRITY;
+               }
        } else {
                /* Ensure we setup the retry handler. */
                set_domain_offline(domain);
@@ -1690,9 +2018,10 @@ static NTSTATUS cm_open_connection(struct winbindd_domain *domain,
 
 /* Close down all open pipes on a connection. */
 
-void invalidate_cm_connection(struct winbindd_cm_conn *conn)
+void invalidate_cm_connection(struct winbindd_domain *domain)
 {
        NTSTATUS result;
+       struct winbindd_cm_conn *conn = &domain->conn;
 
        /* We're closing down a possibly dead
           connection. Don't have impossibly long (10s) timeouts. */
@@ -1751,6 +2080,9 @@ void invalidate_cm_connection(struct winbindd_cm_conn *conn)
                }
        }
 
+       conn->auth_level = DCERPC_AUTH_LEVEL_PRIVACY;
+       TALLOC_FREE(conn->netlogon_creds_ctx);
+
        if (conn->cli) {
                cli_shutdown(conn->cli);
        }
@@ -1773,7 +2105,7 @@ void close_conns_after_fork(void)
                        smbXcli_conn_disconnect(domain->conn.cli->conn, NT_STATUS_OK);
                }
 
-               invalidate_cm_connection(&domain->conn);
+               invalidate_cm_connection(domain);
        }
 
        for (cli_state = winbindd_client_list();
@@ -1808,26 +2140,38 @@ static bool connection_ok(struct winbindd_domain *domain)
 /* Initialize a new connection up to the RPC BIND.
    Bypass online status check so always does network calls. */
 
-static NTSTATUS init_dc_connection_network(struct winbindd_domain *domain)
+static NTSTATUS init_dc_connection_network(struct winbindd_domain *domain, bool need_rw_dc)
 {
        NTSTATUS result;
+       bool skip_connection = domain->internal;
+       if (need_rw_dc && domain->rodc) {
+               skip_connection = false;
+       }
 
        /* Internal connections never use the network. */
-       if (domain->internal) {
-               domain->initialized = True;
-               return NT_STATUS_OK;
+       if (dom_sid_equal(&domain->sid, &global_sid_Builtin)) {
+               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
        }
 
-       if (connection_ok(domain)) {
+       /* Still ask the internal LSA and SAMR server about the local domain */
+       if (skip_connection || connection_ok(domain)) {
                if (!domain->initialized) {
                        set_dc_type_and_flags(domain);
                }
                return NT_STATUS_OK;
        }
 
-       invalidate_cm_connection(&domain->conn);
+       invalidate_cm_connection(domain);
+
+       if (!domain->primary && !domain->initialized) {
+               /*
+                * Before we connect to a trust, work out if it is an
+                * AD domain by asking our own domain.
+                */
+               set_dc_type_and_flags_trustinfo(domain);
+       }
 
-       result = cm_open_connection(domain, &domain->conn);
+       result = cm_open_connection(domain, &domain->conn, need_rw_dc);
 
        if (NT_STATUS_IS_OK(result) && !domain->initialized) {
                set_dc_type_and_flags(domain);
@@ -1836,9 +2180,9 @@ static NTSTATUS init_dc_connection_network(struct winbindd_domain *domain)
        return result;
 }
 
-NTSTATUS init_dc_connection(struct winbindd_domain *domain)
+NTSTATUS init_dc_connection(struct winbindd_domain *domain, bool need_rw_dc)
 {
-       if (domain->internal) {
+       if (dom_sid_equal(&domain->sid, &global_sid_Builtin)) {
                return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
        }
 
@@ -1847,14 +2191,14 @@ NTSTATUS init_dc_connection(struct winbindd_domain *domain)
                return NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND;
        }
 
-       return init_dc_connection_network(domain);
+       return init_dc_connection_network(domain, need_rw_dc);
 }
 
-static NTSTATUS init_dc_connection_rpc(struct winbindd_domain *domain)
+static NTSTATUS init_dc_connection_rpc(struct winbindd_domain *domain, bool need_rw_dc)
 {
        NTSTATUS status;
 
-       status = init_dc_connection(domain);
+       status = init_dc_connection(domain, need_rw_dc);
        if (!NT_STATUS_IS_OK(status)) {
                return status;
        }
@@ -1878,13 +2222,22 @@ static bool set_dc_type_and_flags_trustinfo( struct winbindd_domain *domain )
        WERROR werr;
        struct netr_DomainTrustList trusts;
        int i;
-       uint32 flags = (NETR_TRUST_FLAG_IN_FOREST |
+       uint32_t flags = (NETR_TRUST_FLAG_IN_FOREST |
                        NETR_TRUST_FLAG_OUTBOUND |
                        NETR_TRUST_FLAG_INBOUND);
        struct rpc_pipe_client *cli;
        TALLOC_CTX *mem_ctx = NULL;
        struct dcerpc_binding_handle *b;
 
+       if (IS_DC) {
+               /*
+                * On a DC we loaded all trusts
+                * from configuration and never learn
+                * new domains.
+                */
+               return true;
+       }
+
        DEBUG(5, ("set_dc_type_and_flags_trustinfo: domain %s\n", domain->name ));
 
        /* Our primary domain doesn't need to worry about trust flags.
@@ -1893,38 +2246,46 @@ static bool set_dc_type_and_flags_trustinfo( struct winbindd_domain *domain )
                return False;           
        }
 
+       mem_ctx = talloc_stackframe();
        our_domain = find_our_domain();
-
-       if ( !connection_ok(our_domain) ) {
-               DEBUG(3,("set_dc_type_and_flags_trustinfo: No connection to our domain!\n"));           
-               return False;
+       if (our_domain->internal) {
+               result = init_dc_connection(our_domain, false);
+               if (!NT_STATUS_IS_OK(result)) {
+                       DEBUG(3,("set_dc_type_and_flags_trustinfo: "
+                                "Not able to make a connection to our domain: %s\n",
+                                 nt_errstr(result)));
+                       TALLOC_FREE(mem_ctx);
+                       return false;
+               }
        }
 
        /* This won't work unless our domain is AD */
-
        if ( !our_domain->active_directory ) {
+               TALLOC_FREE(mem_ctx);
                return False;
        }
 
-       /* Use DsEnumerateDomainTrusts to get us the trust direction
-          and type */
-
-       result = cm_connect_netlogon(our_domain, &cli);
+       if (our_domain->internal) {
+               result = wb_open_internal_pipe(mem_ctx, &ndr_table_netlogon, &cli);
+       } else if (!connection_ok(our_domain)) {
+               DEBUG(3,("set_dc_type_and_flags_trustinfo: "
+                        "No connection to our domain!\n"));
+               TALLOC_FREE(mem_ctx);
+               return False;
+       } else {
+               result = cm_connect_netlogon(our_domain, &cli);
+       }
 
        if (!NT_STATUS_IS_OK(result)) {
                DEBUG(5, ("set_dc_type_and_flags_trustinfo: Could not open "
                          "a connection to %s for PIPE_NETLOGON (%s)\n", 
                          domain->name, nt_errstr(result)));
+               TALLOC_FREE(mem_ctx);
                return False;
        }
-
        b = cli->binding_handle;
 
-       if ( (mem_ctx = talloc_init("set_dc_type_and_flags_trustinfo")) == NULL ) {
-               DEBUG(0,("set_dc_type_and_flags_trustinfo: talloc_init() failed!\n"));
-               return False;
-       }       
-
+       /* Use DsEnumerateDomainTrusts to get us the trust direction and type. */
        result = dcerpc_netr_DsrEnumerateDomainTrusts(b, mem_ctx,
                                                      cli->desthost,
                                                      flags,
@@ -1934,14 +2295,14 @@ static bool set_dc_type_and_flags_trustinfo( struct winbindd_domain *domain )
                DEBUG(0,("set_dc_type_and_flags_trustinfo: "
                        "failed to query trusted domain list: %s\n",
                        nt_errstr(result)));
-               talloc_destroy(mem_ctx);
+               TALLOC_FREE(mem_ctx);
                return false;
        }
        if (!W_ERROR_IS_OK(werr)) {
                DEBUG(0,("set_dc_type_and_flags_trustinfo: "
                        "failed to query trusted domain list: %s\n",
                        win_errstr(werr)));
-               talloc_destroy(mem_ctx);
+               TALLOC_FREE(mem_ctx);
                return false;
        }
 
@@ -1953,7 +2314,7 @@ static bool set_dc_type_and_flags_trustinfo( struct winbindd_domain *domain )
                        domain->domain_type           = trusts.array[i].trust_type;
                        domain->domain_trust_attribs  = trusts.array[i].trust_attributes;
 
-                       if ( domain->domain_type == NETR_TRUST_TYPE_UPLEVEL )
+                       if ( domain->domain_type == LSA_TRUST_TYPE_UPLEVEL )
                                domain->active_directory = True;
 
                        /* This flag is only set if the domain is *our* 
@@ -1971,7 +2332,6 @@ static bool set_dc_type_and_flags_trustinfo( struct winbindd_domain *domain )
                                 domain->active_directory ? "" : "NOT "));
 
                        domain->can_do_ncacn_ip_tcp = domain->active_directory;
-                       domain->can_do_validation6 = domain->active_directory;
 
                        domain->initialized = True;
 
@@ -1979,7 +2339,7 @@ static bool set_dc_type_and_flags_trustinfo( struct winbindd_domain *domain )
                }               
        }
 
-       talloc_destroy( mem_ctx );
+       TALLOC_FREE(mem_ctx);
 
        return domain->initialized;     
 }
@@ -2002,7 +2362,7 @@ static void set_dc_type_and_flags_connect( struct winbindd_domain *domain )
        union dssetup_DsRoleInfo info;
        union lsa_PolicyInformation *lsa_info = NULL;
 
-       if (!connection_ok(domain)) {
+       if (!domain->internal && !connection_ok(domain)) {
                return;
        }
 
@@ -2015,9 +2375,15 @@ static void set_dc_type_and_flags_connect( struct winbindd_domain *domain )
 
        DEBUG(5, ("set_dc_type_and_flags_connect: domain %s\n", domain->name ));
 
-       status = cli_rpc_pipe_open_noauth(domain->conn.cli,
-                                         &ndr_table_dssetup,
-                                         &cli);
+       if (domain->internal) {
+               status = wb_open_internal_pipe(mem_ctx,
+                                              &ndr_table_dssetup,
+                                              &cli);
+       } else {
+               status = cli_rpc_pipe_open_noauth(domain->conn.cli,
+                                                 &ndr_table_dssetup,
+                                                 &cli);
+       }
 
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(5, ("set_dc_type_and_flags_connect: Could not bind to "
@@ -2066,9 +2432,14 @@ static void set_dc_type_and_flags_connect( struct winbindd_domain *domain )
        }
 
 no_dssetup:
-       status = cli_rpc_pipe_open_noauth(domain->conn.cli,
-                                         &ndr_table_lsarpc, &cli);
-
+       if (domain->internal) {
+               status = wb_open_internal_pipe(mem_ctx,
+                                              &ndr_table_lsarpc,
+                                              &cli);
+       } else {
+               status = cli_rpc_pipe_open_noauth(domain->conn.cli,
+                                                 &ndr_table_lsarpc, &cli);
+       }
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(5, ("set_dc_type_and_flags_connect: Could not bind to "
                          "PI_LSARPC on domain %s: (%s)\n",
@@ -2095,6 +2466,18 @@ no_dssetup:
                domain->active_directory = True;
 
                if (lsa_info->dns.name.string) {
+                       if (!strequal(domain->name, lsa_info->dns.name.string))
+                       {
+                               DEBUG(1, ("set_dc_type_and_flags_connect: DC "
+                                         "for domain %s claimed it was a DC "
+                                         "for domain %s, refusing to "
+                                         "initialize\n",
+                                         domain->name,
+                                         lsa_info->dns.name.string));
+                               TALLOC_FREE(cli);
+                               TALLOC_FREE(mem_ctx);
+                               return;
+                       }
                        talloc_free(domain->name);
                        domain->name = talloc_strdup(domain,
                                                     lsa_info->dns.name.string);
@@ -2104,6 +2487,20 @@ no_dssetup:
                }
 
                if (lsa_info->dns.dns_domain.string) {
+                       if (domain->alt_name != NULL &&
+                           !strequal(domain->alt_name,
+                                     lsa_info->dns.dns_domain.string))
+                       {
+                               DEBUG(1, ("set_dc_type_and_flags_connect: DC "
+                                         "for domain %s (%s) claimed it was "
+                                         "a DC for domain %s, refusing to "
+                                         "initialize\n",
+                                         domain->alt_name, domain->name,
+                                         lsa_info->dns.dns_domain.string));
+                               TALLOC_FREE(cli);
+                               TALLOC_FREE(mem_ctx);
+                               return;
+                       }
                        talloc_free(domain->alt_name);
                        domain->alt_name =
                                talloc_strdup(domain,
@@ -2131,6 +2528,23 @@ no_dssetup:
                }
 
                if (lsa_info->dns.sid) {
+                       if (!is_null_sid(&domain->sid) &&
+                           !dom_sid_equal(&domain->sid,
+                                          lsa_info->dns.sid))
+                       {
+                               DEBUG(1, ("set_dc_type_and_flags_connect: DC "
+                                         "for domain %s (%s) claimed it was "
+                                         "a DC for domain %s, refusing to "
+                                         "initialize\n",
+                                         dom_sid_string(talloc_tos(),
+                                                        &domain->sid),
+                                         domain->name,
+                                         dom_sid_string(talloc_tos(),
+                                                        lsa_info->dns.sid)));
+                               TALLOC_FREE(cli);
+                               TALLOC_FREE(mem_ctx);
+                               return;
+                       }
                        sid_copy(&domain->sid, lsa_info->dns.sid);
                }
        } else {
@@ -2152,6 +2566,20 @@ no_dssetup:
                if (NT_STATUS_IS_OK(status) && NT_STATUS_IS_OK(result)) {
 
                        if (lsa_info->account_domain.name.string) {
+                               if (!strequal(domain->name,
+                                       lsa_info->account_domain.name.string))
+                               {
+                                       DEBUG(1,
+                                             ("set_dc_type_and_flags_connect: "
+                                              "DC for domain %s claimed it was"
+                                              " a DC for domain %s, refusing "
+                                              "to initialize\n", domain->name,
+                                              lsa_info->
+                                               account_domain.name.string));
+                                       TALLOC_FREE(cli);
+                                       TALLOC_FREE(mem_ctx);
+                                       return;
+                               }
                                talloc_free(domain->name);
                                domain->name =
                                        talloc_strdup(domain,
@@ -2159,6 +2587,24 @@ no_dssetup:
                        }
 
                        if (lsa_info->account_domain.sid) {
+                               if (!is_null_sid(&domain->sid) &&
+                                   !dom_sid_equal(&domain->sid,
+                                               lsa_info->account_domain.sid))
+                               {
+                                       DEBUG(1,
+                                             ("set_dc_type_and_flags_connect: "
+                                              "DC for domain %s (%s) claimed "
+                                              "it was a DC for domain %s, "
+                                              "refusing to initialize\n",
+                                              dom_sid_string(talloc_tos(),
+                                                             &domain->sid),
+                                              domain->name,
+                                              dom_sid_string(talloc_tos(),
+                                               lsa_info->account_domain.sid)));
+                                       TALLOC_FREE(cli);
+                                       TALLOC_FREE(mem_ctx);
+                                       return;
+                               }
                                sid_copy(&domain->sid, lsa_info->account_domain.sid);
                        }
                }
@@ -2172,7 +2618,6 @@ done:
                  domain->name, domain->active_directory ? "" : "NOT "));
 
        domain->can_do_ncacn_ip_tcp = domain->active_directory;
-       domain->can_do_validation6 = domain->active_directory;
 
        TALLOC_FREE(cli);
 
@@ -2187,11 +2632,20 @@ done:
 
 static void set_dc_type_and_flags( struct winbindd_domain *domain )
 {
+       if (IS_DC) {
+               /*
+                * On a DC we loaded all trusts
+                * from configuration and never learn
+                * new domains.
+                */
+               return;
+       }
+
        /* we always have to contact our primary domain */
 
-       if ( domain->primary ) {
+       if ( domain->primary || domain->internal) {
                DEBUG(10,("set_dc_type_and_flags: setting up flags for "
-                         "primary domain\n"));
+                         "primary or internal domain\n"));
                set_dc_type_and_flags_connect( domain );
                return;         
        }
@@ -2213,46 +2667,62 @@ static void set_dc_type_and_flags( struct winbindd_domain *domain )
 ***********************************************************************/
 
 static NTSTATUS cm_get_schannel_creds(struct winbindd_domain *domain,
-                                  struct netlogon_creds_CredentialState **ppdc)
+                                  struct netlogon_creds_cli_context **ppdc)
 {
        NTSTATUS result = NT_STATUS_UNSUCCESSFUL;
        struct rpc_pipe_client *netlogon_pipe;
 
-       if (lp_client_schannel() == False) {
-               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
-       }
+       *ppdc = NULL;
 
-       result = cm_connect_netlogon(domain, &netlogon_pipe);
-       if (!NT_STATUS_IS_OK(result)) {
-               return result;
+       if ((!IS_DC) && (!domain->primary)) {
+               return NT_STATUS_TRUSTED_DOMAIN_FAILURE;
        }
 
-       /* Return a pointer to the struct netlogon_creds_CredentialState from the
-          netlogon pipe. */
+       if (domain->conn.netlogon_creds_ctx != NULL) {
+               *ppdc = domain->conn.netlogon_creds_ctx;
+               return NT_STATUS_OK;
+       }
 
-       if (!domain->conn.netlogon_pipe->dc) {
-               return NT_STATUS_INTERNAL_ERROR; /* This shouldn't happen. */
+       result = cm_connect_netlogon_secure(domain, &netlogon_pipe, ppdc);
+       if (!NT_STATUS_IS_OK(result)) {
+               return result;
        }
 
-       *ppdc = domain->conn.netlogon_pipe->dc;
        return NT_STATUS_OK;
 }
 
 NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
+                       bool need_rw_dc,
                        struct rpc_pipe_client **cli, struct policy_handle *sam_handle)
 {
        struct winbindd_cm_conn *conn;
        NTSTATUS status, result;
-       struct netlogon_creds_CredentialState *p_creds;
-       char *machine_password = NULL;
-       char *machine_account = NULL;
-       const char *domain_name = NULL;
+       struct netlogon_creds_cli_context *p_creds;
+       struct cli_credentials *creds = NULL;
+       bool retry = false; /* allow one retry attempt for expired session */
 
        if (sid_check_is_our_sam(&domain->sid)) {
-               return open_internal_samr_conn(mem_ctx, domain, cli, sam_handle);
+               if (domain->rodc == false || need_rw_dc == false) {
+                       return open_internal_samr_conn(mem_ctx, domain, cli, sam_handle);
+               }
        }
 
-       status = init_dc_connection_rpc(domain);
+       if (IS_AD_DC) {
+               /*
+                * In theory we should not use SAMR within
+                * winbindd at all, but that's a larger task to
+                * remove this and avoid breaking existing
+                * setups.
+                *
+                * At least as AD DC we have the restriction
+                * to avoid SAMR against trusted domains,
+                * as there're no existing setups.
+                */
+               return NT_STATUS_REQUEST_NOT_ACCEPTED;
+       }
+
+retry:
+       status = init_dc_connection_rpc(domain, need_rw_dc);
        if (!NT_STATUS_IS_OK(status)) {
                return status;
        }
@@ -2272,61 +2742,65 @@ NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
         * anonymous.
         */
 
-       if ((conn->cli->user_name[0] == '\0') ||
-           (conn->cli->domain[0] == '\0') || 
-           (conn->cli->password == NULL || conn->cli->password[0] == '\0'))
-       {
-               status = get_trust_creds(domain, &machine_password,
-                                        &machine_account, NULL);
-               if (!NT_STATUS_IS_OK(status)) {
-                       DEBUG(10, ("cm_connect_sam: No no user available for "
-                                  "domain %s, trying schannel\n", conn->cli->domain));
-                       goto schannel;
-               }
-               domain_name = domain->name;
-       } else {
-               machine_password = SMB_STRDUP(conn->cli->password);
-               machine_account = SMB_STRDUP(conn->cli->user_name);
-               domain_name = conn->cli->domain;
+       result = get_trust_credentials(domain, talloc_tos(), false, &creds);
+       if (!NT_STATUS_IS_OK(result)) {
+               DEBUG(10, ("cm_connect_sam: No user available for "
+                          "domain %s, trying schannel\n", domain->name));
+               goto schannel;
        }
 
-       if (!machine_password || !machine_account) {
-               status = NT_STATUS_NO_MEMORY;
-               goto done;
+       if (cli_credentials_is_anonymous(creds)) {
+               goto anonymous;
        }
 
-       /* We have an authenticated connection. Use a NTLMSSP SPNEGO
-          authenticated SAMR pipe with sign & seal. */
-       status = cli_rpc_pipe_open_spnego(conn->cli,
-                                         &ndr_table_samr,
-                                         NCACN_NP,
-                                         GENSEC_OID_NTLMSSP,
-                                         DCERPC_AUTH_LEVEL_PRIVACY,
-                                         smbXcli_conn_remote_name(conn->cli->conn),
-                                         domain_name,
-                                         machine_account,
-                                         machine_password,
-                                         &conn->samr_pipe);
+       /*
+        * We have an authenticated connection. Use a SPNEGO
+        * authenticated SAMR pipe with sign & seal.
+        */
+       status = cli_rpc_pipe_open_with_creds(conn->cli,
+                                             &ndr_table_samr,
+                                             NCACN_NP,
+                                             DCERPC_AUTH_TYPE_SPNEGO,
+                                             conn->auth_level,
+                                             smbXcli_conn_remote_name(conn->cli->conn),
+                                             creds,
+                                             &conn->samr_pipe);
+
+       if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_SESSION_EXPIRED)
+           && !retry) {
+               invalidate_cm_connection(domain);
+               retry = true;
+               goto retry;
+       }
 
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(10,("cm_connect_sam: failed to connect to SAMR "
                          "pipe for domain %s using NTLMSSP "
-                         "authenticated pipe: user %s\\%s. Error was "
-                         "%s\n", domain->name, domain_name,
-                         machine_account, nt_errstr(status)));
+                         "authenticated pipe: user %s. Error was "
+                         "%s\n", domain->name,
+                         cli_credentials_get_unparsed_name(creds, talloc_tos()),
+                         nt_errstr(status)));
                goto schannel;
        }
 
        DEBUG(10,("cm_connect_sam: connected to SAMR pipe for "
                  "domain %s using NTLMSSP authenticated "
-                 "pipe: user %s\\%s\n", domain->name,
-                 domain_name, machine_account));
+                 "pipe: user %s\n", domain->name,
+                 cli_credentials_get_unparsed_name(creds, talloc_tos())));
 
        status = dcerpc_samr_Connect2(conn->samr_pipe->binding_handle, mem_ctx,
                                      conn->samr_pipe->desthost,
                                      SEC_FLAG_MAXIMUM_ALLOWED,
                                      &conn->sam_connect_handle,
                                      &result);
+
+       if (NT_STATUS_EQUAL(status, NT_STATUS_IO_DEVICE_ERROR) && !retry) {
+               invalidate_cm_connection(domain);
+               TALLOC_FREE(conn->samr_pipe);
+               retry = true;
+               goto retry;
+       }
+
        if (NT_STATUS_IS_OK(status) && NT_STATUS_IS_OK(result)) {
                goto open_domain;
        }
@@ -2352,10 +2826,17 @@ NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
                        nt_errstr(status) ));
                goto anonymous;
        }
-       status = cli_rpc_pipe_open_schannel_with_key
-               (conn->cli, &ndr_table_samr, NCACN_NP,
-                DCERPC_AUTH_LEVEL_PRIVACY,
-                domain->name, &p_creds, &conn->samr_pipe);
+       TALLOC_FREE(creds);
+       status = cli_rpc_pipe_open_schannel_with_creds(
+               conn->cli, &ndr_table_samr, NCACN_NP, p_creds,
+               &conn->samr_pipe);
+
+       if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_SESSION_EXPIRED)
+           && !retry) {
+               invalidate_cm_connection(domain);
+               retry = true;
+               goto retry;
+       }
 
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(10,("cm_connect_sam: failed to connect to SAMR pipe for "
@@ -2371,6 +2852,14 @@ NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
                                      SEC_FLAG_MAXIMUM_ALLOWED,
                                      &conn->sam_connect_handle,
                                      &result);
+
+       if (NT_STATUS_EQUAL(status, NT_STATUS_IO_DEVICE_ERROR) && !retry) {
+               invalidate_cm_connection(domain);
+               TALLOC_FREE(conn->samr_pipe);
+               retry = true;
+               goto retry;
+       }
+
        if (NT_STATUS_IS_OK(status) && NT_STATUS_IS_OK(result)) {
                goto open_domain;
        }
@@ -2385,9 +2874,25 @@ NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
  anonymous:
 
        /* Finally fall back to anonymous. */
+       if (lp_winbind_sealed_pipes() || lp_require_strong_key()) {
+               status = NT_STATUS_DOWNGRADE_DETECTED;
+               DEBUG(1, ("Unwilling to make SAMR connection to domain %s "
+                         "without connection level security, "
+                         "must set 'winbind sealed pipes = false' and "
+                         "'require strong key = false' to proceed: %s\n",
+                         domain->name, nt_errstr(status)));
+               goto done;
+       }
        status = cli_rpc_pipe_open_noauth(conn->cli, &ndr_table_samr,
                                          &conn->samr_pipe);
 
+       if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_SESSION_EXPIRED)
+           && !retry) {
+               invalidate_cm_connection(domain);
+               retry = true;
+               goto retry;
+       }
+
        if (!NT_STATUS_IS_OK(status)) {
                goto done;
        }
@@ -2397,6 +2902,14 @@ NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
                                      SEC_FLAG_MAXIMUM_ALLOWED,
                                      &conn->sam_connect_handle,
                                      &result);
+
+       if (NT_STATUS_EQUAL(status, NT_STATUS_IO_DEVICE_ERROR) && !retry) {
+               invalidate_cm_connection(domain);
+               TALLOC_FREE(conn->samr_pipe);
+               retry = true;
+               goto retry;
+       }
+
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(10,("cm_connect_sam: rpccli_samr_Connect2 failed "
                          "for domain %s Error was %s\n",
@@ -2438,14 +2951,12 @@ NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
                ZERO_STRUCT(conn->sam_domain_handle);
                return status;
        } else if (!NT_STATUS_IS_OK(status)) {
-               invalidate_cm_connection(conn);
+               invalidate_cm_connection(domain);
                return status;
        }
 
        *cli = conn->samr_pipe;
        *sam_handle = conn->sam_domain_handle;
-       SAFE_FREE(machine_password);
-       SAFE_FREE(machine_account);
        return status;
 }
 
@@ -2453,44 +2964,44 @@ NTSTATUS cm_connect_sam(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
  open an schanneld ncacn_ip_tcp connection to LSA
 ***********************************************************************/
 
-NTSTATUS cm_connect_lsa_tcp(struct winbindd_domain *domain,
-                           TALLOC_CTX *mem_ctx,
-                           struct rpc_pipe_client **cli)
+static NTSTATUS cm_connect_lsa_tcp(struct winbindd_domain *domain,
+                                  TALLOC_CTX *mem_ctx,
+                                  struct rpc_pipe_client **cli)
 {
        struct winbindd_cm_conn *conn;
-       struct netlogon_creds_CredentialState *creds;
+       struct netlogon_creds_cli_context *p_creds = NULL;
        NTSTATUS status;
 
        DEBUG(10,("cm_connect_lsa_tcp\n"));
 
-       status = init_dc_connection_rpc(domain);
+       status = init_dc_connection_rpc(domain, false);
        if (!NT_STATUS_IS_OK(status)) {
                return status;
        }
 
        conn = &domain->conn;
 
-       if (conn->lsa_pipe_tcp &&
+       /*
+        * rpccli_is_connected handles more error cases
+        */
+       if (rpccli_is_connected(conn->lsa_pipe_tcp) &&
            conn->lsa_pipe_tcp->transport->transport == NCACN_IP_TCP &&
-           conn->lsa_pipe_tcp->auth->auth_level == DCERPC_AUTH_LEVEL_PRIVACY &&
-           rpccli_is_connected(conn->lsa_pipe_tcp)) {
+           conn->lsa_pipe_tcp->auth->auth_level >= DCERPC_AUTH_LEVEL_INTEGRITY) {
                goto done;
        }
 
        TALLOC_FREE(conn->lsa_pipe_tcp);
 
-       status = cm_get_schannel_creds(domain, &creds);
+       status = cm_get_schannel_creds(domain, &p_creds);
        if (!NT_STATUS_IS_OK(status)) {
                goto done;
        }
 
-       status = cli_rpc_pipe_open_schannel_with_key(conn->cli,
-                                                    &ndr_table_lsarpc,
-                                                    NCACN_IP_TCP,
-                                                    DCERPC_AUTH_LEVEL_PRIVACY,
-                                                    domain->name,
-                                                    &creds,
-                                                    &conn->lsa_pipe_tcp);
+       status = cli_rpc_pipe_open_schannel_with_creds(conn->cli,
+                                                      &ndr_table_lsarpc,
+                                                      NCACN_IP_TCP,
+                                                      p_creds,
+                                                      &conn->lsa_pipe_tcp);
        if (!NT_STATUS_IS_OK(status)) {
                DEBUG(10,("cli_rpc_pipe_open_schannel_with_key failed: %s\n",
                        nt_errstr(status)));
@@ -2513,9 +3024,12 @@ NTSTATUS cm_connect_lsa(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
 {
        struct winbindd_cm_conn *conn;
        NTSTATUS result = NT_STATUS_UNSUCCESSFUL;
-       struct netlogon_creds_CredentialState *p_creds;
+       struct netlogon_creds_cli_context *p_creds;
+       struct cli_credentials *creds = NULL;
+       bool retry = false; /* allow one retry attempt for expired session */
 
-       result = init_dc_connection_rpc(domain);
+retry:
+       result = init_dc_connection_rpc(domain, false);
        if (!NT_STATUS_IS_OK(result))
                return result;
 
@@ -2527,40 +3041,67 @@ NTSTATUS cm_connect_lsa(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
 
        TALLOC_FREE(conn->lsa_pipe);
 
-       if ((conn->cli->user_name[0] == '\0') ||
-           (conn->cli->domain[0] == '\0') || 
-           (conn->cli->password == NULL || conn->cli->password[0] == '\0')) {
-               DEBUG(10, ("cm_connect_lsa: No no user available for "
-                          "domain %s, trying schannel\n", conn->cli->domain));
+       if (IS_AD_DC) {
+               /*
+                * Make sure we only use schannel as AD DC.
+                */
                goto schannel;
        }
 
-       /* We have an authenticated connection. Use a NTLMSSP SPNEGO
-        * authenticated LSA pipe with sign & seal. */
-       result = cli_rpc_pipe_open_spnego
+       result = get_trust_credentials(domain, talloc_tos(), false, &creds);
+       if (!NT_STATUS_IS_OK(result)) {
+               DEBUG(10, ("cm_connect_lsa: No user available for "
+                          "domain %s, trying schannel\n", domain->name));
+               goto schannel;
+       }
+
+       if (cli_credentials_is_anonymous(creds)) {
+               goto anonymous;
+       }
+
+       /*
+        * We have an authenticated connection. Use a SPNEGO
+        * authenticated LSA pipe with sign & seal.
+        */
+       result = cli_rpc_pipe_open_with_creds
                (conn->cli, &ndr_table_lsarpc, NCACN_NP,
-                GENSEC_OID_NTLMSSP,
-                DCERPC_AUTH_LEVEL_PRIVACY,
+                DCERPC_AUTH_TYPE_SPNEGO,
+                conn->auth_level,
                 smbXcli_conn_remote_name(conn->cli->conn),
-                conn->cli->domain, conn->cli->user_name, conn->cli->password,
+                creds,
                 &conn->lsa_pipe);
 
+       if (NT_STATUS_EQUAL(result, NT_STATUS_NETWORK_SESSION_EXPIRED)
+           && !retry) {
+               invalidate_cm_connection(domain);
+               retry = true;
+               goto retry;
+       }
+
        if (!NT_STATUS_IS_OK(result)) {
                DEBUG(10,("cm_connect_lsa: failed to connect to LSA pipe for "
                          "domain %s using NTLMSSP authenticated pipe: user "
-                         "%s\\%s. Error was %s. Trying schannel.\n",
-                         domain->name, conn->cli->domain,
-                         conn->cli->user_name, nt_errstr(result)));
+                         "%s. Error was %s. Trying schannel.\n",
+                         domain->name,
+                         cli_credentials_get_unparsed_name(creds, talloc_tos()),
+                         nt_errstr(result)));
                goto schannel;
        }
 
        DEBUG(10,("cm_connect_lsa: connected to LSA pipe for domain %s using "
-                 "NTLMSSP authenticated pipe: user %s\\%s\n",
-                 domain->name, conn->cli->domain, conn->cli->user_name ));
+                 "NTLMSSP authenticated pipe: user %s\n",
+                 domain->name, cli_credentials_get_unparsed_name(creds, talloc_tos())));
 
        result = rpccli_lsa_open_policy(conn->lsa_pipe, mem_ctx, True,
                                        SEC_FLAG_MAXIMUM_ALLOWED,
                                        &conn->lsa_policy);
+       if (NT_STATUS_EQUAL(result, NT_STATUS_IO_DEVICE_ERROR) && !retry) {
+               invalidate_cm_connection(domain);
+               TALLOC_FREE(conn->lsa_pipe);
+               retry = true;
+               goto retry;
+       }
+
        if (NT_STATUS_IS_OK(result)) {
                goto done;
        }
@@ -2583,10 +3124,18 @@ NTSTATUS cm_connect_lsa(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
                        nt_errstr(result) ));
                goto anonymous;
        }
-       result = cli_rpc_pipe_open_schannel_with_key
-               (conn->cli, &ndr_table_lsarpc, NCACN_NP,
-                DCERPC_AUTH_LEVEL_PRIVACY,
-                domain->name, &p_creds, &conn->lsa_pipe);
+
+       TALLOC_FREE(creds);
+       result = cli_rpc_pipe_open_schannel_with_creds(
+               conn->cli, &ndr_table_lsarpc, NCACN_NP, p_creds,
+               &conn->lsa_pipe);
+
+       if (NT_STATUS_EQUAL(result, NT_STATUS_NETWORK_SESSION_EXPIRED)
+           && !retry) {
+               invalidate_cm_connection(domain);
+               retry = true;
+               goto retry;
+       }
 
        if (!NT_STATUS_IS_OK(result)) {
                DEBUG(10,("cm_connect_lsa: failed to connect to LSA pipe for "
@@ -2600,10 +3149,25 @@ NTSTATUS cm_connect_lsa(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
        result = rpccli_lsa_open_policy(conn->lsa_pipe, mem_ctx, True,
                                        SEC_FLAG_MAXIMUM_ALLOWED,
                                        &conn->lsa_policy);
+
+       if (NT_STATUS_EQUAL(result, NT_STATUS_IO_DEVICE_ERROR) && !retry) {
+               invalidate_cm_connection(domain);
+               TALLOC_FREE(conn->lsa_pipe);
+               retry = true;
+               goto retry;
+       }
+
        if (NT_STATUS_IS_OK(result)) {
                goto done;
        }
 
+       if (IS_AD_DC) {
+               /*
+                * Make sure we only use schannel as AD DC.
+                */
+               goto done;
+       }
+
        DEBUG(10,("cm_connect_lsa: rpccli_lsa_open_policy failed, trying "
                  "anonymous\n"));
 
@@ -2611,20 +3175,52 @@ NTSTATUS cm_connect_lsa(struct winbindd_domain *domain, TALLOC_CTX *mem_ctx,
 
  anonymous:
 
+       if (IS_AD_DC) {
+               /*
+                * Make sure we only use schannel as AD DC.
+                */
+               goto done;
+       }
+
+       if (lp_winbind_sealed_pipes() || lp_require_strong_key()) {
+               result = NT_STATUS_DOWNGRADE_DETECTED;
+               DEBUG(1, ("Unwilling to make LSA connection to domain %s "
+                         "without connection level security, "
+                         "must set 'winbind sealed pipes = false' and "
+                         "'require strong key = false' to proceed: %s\n",
+                         domain->name, nt_errstr(result)));
+               goto done;
+       }
+
        result = cli_rpc_pipe_open_noauth(conn->cli,
                                          &ndr_table_lsarpc,
                                          &conn->lsa_pipe);
+
+       if (NT_STATUS_EQUAL(result, NT_STATUS_NETWORK_SESSION_EXPIRED)
+           && !retry) {
+               invalidate_cm_connection(domain);
+               retry = true;
+               goto retry;
+       }
+
        if (!NT_STATUS_IS_OK(result)) {
-               result = NT_STATUS_PIPE_NOT_AVAILABLE;
                goto done;
        }
 
        result = rpccli_lsa_open_policy(conn->lsa_pipe, mem_ctx, True,
                                        SEC_FLAG_MAXIMUM_ALLOWED,
                                        &conn->lsa_policy);
+
+       if (NT_STATUS_EQUAL(result, NT_STATUS_IO_DEVICE_ERROR) && !retry) {
+               invalidate_cm_connection(domain);
+               TALLOC_FREE(conn->lsa_pipe);
+               retry = true;
+               goto retry;
+       }
+
  done:
        if (!NT_STATUS_IS_OK(result)) {
-               invalidate_cm_connection(conn);
+               invalidate_cm_connection(domain);
                return result;
        }
 
@@ -2649,7 +3245,7 @@ NTSTATUS cm_connect_lsat(struct winbindd_domain *domain,
                if (NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED) ||
                    NT_STATUS_EQUAL(status, NT_STATUS_RPC_SEC_PKG_ERROR) ||
                    NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_ACCESS_DENIED)) {
-                       invalidate_cm_connection(&domain->conn);
+                       invalidate_cm_connection(domain);
                        status = cm_connect_lsa_tcp(domain, mem_ctx, cli);
                }
                if (NT_STATUS_IS_OK(status)) {
@@ -2660,6 +3256,8 @@ NTSTATUS cm_connect_lsat(struct winbindd_domain *domain,
                 * we tried twice to connect via ncan_ip_tcp and schannel and
                 * failed - maybe it is a trusted domain we can't connect to ?
                 * do not try tcp next time - gd
+                *
+                * This also prevents NETLOGON over TCP
                 */
                domain->can_do_ncacn_ip_tcp = false;
        }
@@ -2670,25 +3268,33 @@ NTSTATUS cm_connect_lsat(struct winbindd_domain *domain,
 }
 
 /****************************************************************************
- Open the netlogon pipe to this DC. Use schannel if specified in client conf.
- session key stored in conn->netlogon_pipe->dc->sess_key.
+ Open the netlogon pipe to this DC.
 ****************************************************************************/
 
-NTSTATUS cm_connect_netlogon(struct winbindd_domain *domain,
-                            struct rpc_pipe_client **cli)
+static NTSTATUS cm_connect_netlogon_transport(struct winbindd_domain *domain,
+                                             enum dcerpc_transport_t transport,
+                                             struct rpc_pipe_client **cli)
 {
+       struct messaging_context *msg_ctx = server_messaging_context();
        struct winbindd_cm_conn *conn;
        NTSTATUS result;
-
-       uint32_t neg_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS | NETLOGON_NEG_SUPPORTS_AES;
-       uint8_t  mach_pwd[16];
        enum netr_SchannelType sec_chan_type;
-       const char *account_name;
-       struct rpc_pipe_client *netlogon_pipe = NULL;
+       struct cli_credentials *creds = NULL;
 
        *cli = NULL;
 
-       result = init_dc_connection_rpc(domain);
+       if (IS_AD_DC) {
+               if (domain->secure_channel_type == SEC_CHAN_NULL) {
+                       /*
+                        * Make sure we don't even try to
+                        * connect to a foreign domain
+                        * without a direct outbound trust.
+                        */
+                       return NT_STATUS_NO_TRUST_LSA_SECRET;
+               }
+       }
+
+       result = init_dc_connection_rpc(domain, domain->rodc);
        if (!NT_STATUS_IS_OK(result)) {
                return result;
        }
@@ -2701,99 +3307,146 @@ NTSTATUS cm_connect_netlogon(struct winbindd_domain *domain,
        }
 
        TALLOC_FREE(conn->netlogon_pipe);
+       TALLOC_FREE(conn->netlogon_creds_ctx);
 
-       result = cli_rpc_pipe_open_noauth(conn->cli,
-                                         &ndr_table_netlogon,
-                                         &netlogon_pipe);
+       result = get_trust_credentials(domain, talloc_tos(), true, &creds);
        if (!NT_STATUS_IS_OK(result)) {
-               return result;
+               DBG_DEBUG("No user available for domain %s when trying "
+                         "schannel\n", domain->name);
+               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
        }
 
-       if ((!IS_DC) && (!domain->primary)) {
-               /* Clear the schannel request bit and drop down */
-               neg_flags &= ~NETLOGON_NEG_SCHANNEL;            
-               goto no_schannel;
+       if (cli_credentials_is_anonymous(creds)) {
+               DBG_WARNING("get_trust_credential only gave anonymous for %s, "
+                           "unable to make get NETLOGON credentials\n",
+                           domain->name);
+               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
        }
 
-       if (lp_client_schannel() != False) {
-               neg_flags |= NETLOGON_NEG_SCHANNEL;
-       }
+       sec_chan_type = cli_credentials_get_secure_channel_type(creds);
+       if (sec_chan_type == SEC_CHAN_NULL) {
+               if (transport == NCACN_IP_TCP) {
+                       DBG_NOTICE("get_secure_channel_type gave SEC_CHAN_NULL "
+                                  "for %s, deny NCACN_IP_TCP and let the "
+                                  "caller fallback to NCACN_NP.\n",
+                                  domain->name);
+                       return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
+               }
 
-       if (!get_trust_pw_hash(domain->name, mach_pwd, &account_name,
-                              &sec_chan_type))
-       {
-               TALLOC_FREE(netlogon_pipe);
-               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
+               DBG_NOTICE("get_secure_channel_type gave SEC_CHAN_NULL for %s, "
+                          "fallback to noauth on NCACN_NP.\n",
+                          domain->name);
+
+               result = cli_rpc_pipe_open_noauth_transport(
+                       conn->cli,
+                       transport,
+                       &ndr_table_netlogon,
+                       &conn->netlogon_pipe);
+               if (!NT_STATUS_IS_OK(result)) {
+                       invalidate_cm_connection(domain);
+                       return result;
+               }
+
+               *cli = conn->netlogon_pipe;
+               return NT_STATUS_OK;
        }
 
-       result = rpccli_netlogon_setup_creds(
-                netlogon_pipe,
-                domain->dcname, /* server name. */
-                domain->name,   /* domain name */
-                lp_netbios_name(), /* client name */
-                account_name,   /* machine account */
-                mach_pwd,       /* machine password */
-                sec_chan_type,  /* from get_trust_pw */
-                &neg_flags);
+       result = rpccli_create_netlogon_creds_ctx(creds,
+                                                 domain->dcname,
+                                                 msg_ctx,
+                                                 domain,
+                                                 &conn->netlogon_creds_ctx);
+       if (!NT_STATUS_IS_OK(result)) {
+               DEBUG(1, ("rpccli_create_netlogon_creds failed for %s, "
+                         "unable to create NETLOGON credentials: %s\n",
+                         domain->name, nt_errstr(result)));
+               return result;
+       }
 
+       result = rpccli_connect_netlogon(
+               conn->cli, transport,
+               conn->netlogon_creds_ctx, conn->netlogon_force_reauth, creds,
+               &conn->netlogon_pipe);
+       conn->netlogon_force_reauth = false;
        if (!NT_STATUS_IS_OK(result)) {
-               TALLOC_FREE(netlogon_pipe);
+               DBG_DEBUG("rpccli_connect_netlogon failed: %s\n",
+                         nt_errstr(result));
                return result;
        }
 
-       if ((lp_client_schannel() == True) &&
-                       ((neg_flags & NETLOGON_NEG_SCHANNEL) == 0)) {
-               DEBUG(3, ("Server did not offer schannel\n"));
-               TALLOC_FREE(netlogon_pipe);
-               return NT_STATUS_ACCESS_DENIED;
+       *cli = conn->netlogon_pipe;
+       return NT_STATUS_OK;
+}
+
+/****************************************************************************
+Open a NETLOGON connection to a DC, suiteable for SamLogon calls.
+****************************************************************************/
+
+NTSTATUS cm_connect_netlogon(struct winbindd_domain *domain,
+                            struct rpc_pipe_client **cli)
+{
+       NTSTATUS status;
+
+       status = init_dc_connection_rpc(domain, domain->rodc);
+       if (!NT_STATUS_IS_OK(status)) {
+               return status;
        }
 
- no_schannel:
-       if ((lp_client_schannel() == False) ||
-                       ((neg_flags & NETLOGON_NEG_SCHANNEL) == 0)) {
+       if (domain->active_directory && domain->can_do_ncacn_ip_tcp) {
+               status = cm_connect_netlogon_transport(domain, NCACN_IP_TCP, cli);
+               if (NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED) ||
+                   NT_STATUS_EQUAL(status, NT_STATUS_RPC_SEC_PKG_ERROR) ||
+                   NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_ACCESS_DENIED)) {
+                       invalidate_cm_connection(domain);
+                       status = cm_connect_netlogon_transport(domain, NCACN_IP_TCP, cli);
+               }
+               if (NT_STATUS_IS_OK(status)) {
+                       return status;
+               }
+
                /*
-                * NetSamLogonEx only works for schannel
+                * we tried twice to connect via ncan_ip_tcp and schannel and
+                * failed - maybe it is a trusted domain we can't connect to ?
+                * do not try tcp next time - gd
+                *
+                * This also prevents LSA over TCP
                 */
-               domain->can_do_samlogon_ex = False;
-
-               /* We're done - just keep the existing connection to NETLOGON
-                * open */
-               conn->netlogon_pipe = netlogon_pipe;
-               *cli = conn->netlogon_pipe;
-               return NT_STATUS_OK;
+               domain->can_do_ncacn_ip_tcp = false;
        }
 
-       /* Using the credentials from the first pipe, open a signed and sealed
-          second netlogon pipe. The session key is stored in the schannel
-          part of the new pipe auth struct.
-       */
+       status = cm_connect_netlogon_transport(domain, NCACN_NP, cli);
+       if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_SESSION_EXPIRED)) {
+               /*
+                * SMB2 session expired, needs reauthentication. Drop
+                * connection and retry.
+                */
+               invalidate_cm_connection(domain);
+               status = cm_connect_netlogon_transport(domain, NCACN_NP, cli);
+       }
 
-       result = cli_rpc_pipe_open_schannel_with_key(
-               conn->cli, &ndr_table_netlogon, NCACN_NP,
-               DCERPC_AUTH_LEVEL_PRIVACY, domain->name, &netlogon_pipe->dc,
-               &conn->netlogon_pipe);
+       return status;
+}
 
-       /* We can now close the initial netlogon pipe. */
-       TALLOC_FREE(netlogon_pipe);
+NTSTATUS cm_connect_netlogon_secure(struct winbindd_domain *domain,
+                                   struct rpc_pipe_client **cli,
+                                   struct netlogon_creds_cli_context **ppdc)
+{
+       NTSTATUS status;
 
-       if (!NT_STATUS_IS_OK(result)) {
-               DEBUG(3, ("Could not open schannel'ed NETLOGON pipe. Error "
-                         "was %s\n", nt_errstr(result)));
+       if (domain->secure_channel_type == SEC_CHAN_NULL) {
+               return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
+       }
 
-               invalidate_cm_connection(conn);
-               return result;
+       status = cm_connect_netlogon(domain, cli);
+       if (!NT_STATUS_IS_OK(status)) {
+               return status;
        }
 
-       /*
-        * Always try netr_LogonSamLogonEx. We will fall back for NT4
-        * which gives DCERPC_FAULT_OP_RNG_ERROR (function not
-        * supported). We used to only try SamLogonEx for AD, but
-        * Samba DCs can also do it. And because we don't distinguish
-        * between Samba and NT4, always try it once.
-        */
-       domain->can_do_samlogon_ex = true;
+       if (domain->conn.netlogon_creds_ctx == NULL) {
+               return NT_STATUS_TRUSTED_DOMAIN_FAILURE;
+       }
 
-       *cli = conn->netlogon_pipe;
+       *ppdc = domain->conn.netlogon_creds_ctx;
        return NT_STATUS_OK;
 }
 
@@ -2856,3 +3509,19 @@ void winbind_msg_ip_dropped(struct messaging_context *msg_ctx,
        }
        TALLOC_FREE(freeit);
 }
+
+void winbind_msg_disconnect_dc(struct messaging_context *msg_ctx,
+                              void *private_data,
+                              uint32_t msg_type,
+                              struct server_id server_id,
+                              DATA_BLOB *data)
+{
+       struct winbindd_domain *domain;
+
+       for (domain = domain_list(); domain; domain = domain->next) {
+               if (domain->internal) {
+                       continue;
+               }
+               invalidate_cm_connection(domain);
+       }
+}