/* Unix SMB/CIFS implementation. KDC Server startup Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005-2008 Copyright (C) Andrew Tridgell 2005 Copyright (C) Stefan Metzmacher 2005 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "includes.h" #include "smbd/service_task.h" #include "smbd/service.h" #include "smbd/service_stream.h" #include "smbd/process_model.h" #include "lib/events/events.h" #include "lib/socket/socket.h" #include "lib/tsocket/tsocket.h" #include "libcli/util/tstream.h" #include "system/network.h" #include "../lib/util/dlinklist.h" #include "lib/messaging/irpc.h" #include "lib/stream/packet.h" #include "librpc/gen_ndr/samr.h" #include "librpc/gen_ndr/ndr_irpc.h" #include "librpc/gen_ndr/ndr_krb5pac.h" #include "lib/socket/netif.h" #include "param/param.h" #include "kdc/kdc.h" #include "librpc/gen_ndr/ndr_misc.h" extern struct krb5plugin_windc_ftable windc_plugin_table; extern struct hdb_method hdb_samba4; typedef bool (*kdc_process_fn_t)(struct kdc_server *kdc, TALLOC_CTX *mem_ctx, DATA_BLOB *input, DATA_BLOB *reply, struct tsocket_address *peer_addr, struct tsocket_address *my_addr, int datagram); /* hold information about one kdc socket */ struct kdc_socket { struct kdc_server *kdc; struct tsocket_address *local_address; kdc_process_fn_t process; }; /* state of an open tcp connection */ struct kdc_tcp_connection { /* stream connection we belong to */ struct stream_connection *conn; /* the kdc_server the connection belongs to */ struct kdc_socket *kdc_socket; struct tstream_context *tstream; struct tevent_queue *send_queue; }; static void kdc_tcp_terminate_connection(struct kdc_tcp_connection *kdcconn, const char *reason) { stream_terminate_connection(kdcconn->conn, reason); } static void kdc_tcp_recv(struct stream_connection *conn, uint16_t flags) { struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private_data, struct kdc_tcp_connection); /* this should never be triggered! */ kdc_tcp_terminate_connection(kdcconn, "kdc_tcp_recv: called"); } static void kdc_tcp_send(struct stream_connection *conn, uint16_t flags) { struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private_data, struct kdc_tcp_connection); /* this should never be triggered! */ kdc_tcp_terminate_connection(kdcconn, "kdc_tcp_send: called"); } /** Wrapper for krb5_kdc_process_krb5_request, converting to/from Samba calling conventions */ static bool kdc_process(struct kdc_server *kdc, TALLOC_CTX *mem_ctx, DATA_BLOB *input, DATA_BLOB *reply, struct tsocket_address *peer_addr, struct tsocket_address *my_addr, int datagram_reply) { int ret; char *pa; struct sockaddr_storage ss; krb5_data k5_reply; krb5_data_zero(&k5_reply); krb5_kdc_update_time(NULL); ret = tsocket_address_bsd_sockaddr(peer_addr, (struct sockaddr *) &ss, sizeof(struct sockaddr_storage)); if (ret < 0) { return false; } pa = tsocket_address_string(peer_addr, mem_ctx); if (pa == NULL) { return false; } DEBUG(10,("Received KDC packet of length %lu from %s\n", (long)input->length - 4, pa)); ret = krb5_kdc_process_krb5_request(kdc->smb_krb5_context->krb5_context, kdc->config, input->data, input->length, &k5_reply, pa, (struct sockaddr *) &ss, datagram_reply); if (ret == -1) { *reply = data_blob(NULL, 0); return false; } if (k5_reply.length) { *reply = data_blob_talloc(mem_ctx, k5_reply.data, k5_reply.length); krb5_data_free(&k5_reply); } else { *reply = data_blob(NULL, 0); } return true; } struct kdc_tcp_call { struct kdc_tcp_connection *kdc_conn; DATA_BLOB in; DATA_BLOB out; uint8_t out_hdr[4]; struct iovec out_iov[2]; }; static void kdc_tcp_call_writev_done(struct tevent_req *subreq); static void kdc_tcp_call_loop(struct tevent_req *subreq) { struct kdc_tcp_connection *kdc_conn = tevent_req_callback_data(subreq, struct kdc_tcp_connection); struct kdc_tcp_call *call; NTSTATUS status; bool ok; call = talloc(kdc_conn, struct kdc_tcp_call); if (call == NULL) { kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: " "no memory for kdc_tcp_call"); return; } call->kdc_conn = kdc_conn; status = tstream_read_pdu_blob_recv(subreq, call, &call->in); TALLOC_FREE(subreq); if (!NT_STATUS_IS_OK(status)) { const char *reason; reason = talloc_asprintf(call, "kdc_tcp_call_loop: " "tstream_read_pdu_blob_recv() - %s", nt_errstr(status)); if (!reason) { reason = nt_errstr(status); } kdc_tcp_terminate_connection(kdc_conn, reason); return; } DEBUG(10,("Received krb5 TCP packet of length %lu from %s\n", (long) call->in.length, tsocket_address_string(kdc_conn->conn->remote_address, call))); /* skip length header */ call->in.data +=4; call->in.length -= 4; /* Call krb5 */ ok = kdc_conn->kdc_socket->process(kdc_conn->kdc_socket->kdc, call, &call->in, &call->out, kdc_conn->conn->remote_address, kdc_conn->conn->local_address, 0 /* Stream */); if (!ok) { kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: process function failed"); return; } /* First add the length of the out buffer */ RSIVAL(call->out_hdr, 0, call->out.length); call->out_iov[0].iov_base = (char *) call->out_hdr; call->out_iov[0].iov_len = 4; call->out_iov[1].iov_base = (char *) call->out.data; call->out_iov[1].iov_len = call->out.length; subreq = tstream_writev_queue_send(call, kdc_conn->conn->event.ctx, kdc_conn->tstream, kdc_conn->send_queue, call->out_iov, 2); if (subreq == NULL) { kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: " "no memory for tstream_writev_queue_send"); return; } tevent_req_set_callback(subreq, kdc_tcp_call_writev_done, call); /* * The krb5 tcp pdu's has the length as 4 byte (initial_read_size), * packet_full_request_u32 provides the pdu length then. */ subreq = tstream_read_pdu_blob_send(kdc_conn, kdc_conn->conn->event.ctx, kdc_conn->tstream, 4, /* initial_read_size */ packet_full_request_u32, kdc_conn); if (subreq == NULL) { kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_call_loop: " "no memory for tstream_read_pdu_blob_send"); return; } tevent_req_set_callback(subreq, kdc_tcp_call_loop, kdc_conn); } static void kdc_tcp_call_writev_done(struct tevent_req *subreq) { struct kdc_tcp_call *call = tevent_req_callback_data(subreq, struct kdc_tcp_call); int sys_errno; int rc; rc = tstream_writev_queue_recv(subreq, &sys_errno); TALLOC_FREE(subreq); if (rc == -1) { const char *reason; reason = talloc_asprintf(call, "kdc_tcp_call_writev_done: " "tstream_writev_queue_recv() - %d:%s", sys_errno, strerror(sys_errno)); if (!reason) { reason = "kdc_tcp_call_writev_done: tstream_writev_queue_recv() failed"; } kdc_tcp_terminate_connection(call->kdc_conn, reason); return; } /* We don't care about errors */ talloc_free(call); } /* called when we get a new connection */ static void kdc_tcp_accept(struct stream_connection *conn) { struct kdc_socket *kdc_socket; struct kdc_tcp_connection *kdc_conn; struct tevent_req *subreq; int rc; kdc_conn = talloc_zero(conn, struct kdc_tcp_connection); if (kdc_conn == NULL) { stream_terminate_connection(conn, "kdc_tcp_accept: out of memory"); return; } kdc_conn->send_queue = tevent_queue_create(conn, "kdc_tcp_accept"); if (kdc_conn->send_queue == NULL) { stream_terminate_connection(conn, "kdc_tcp_accept: out of memory"); return; } kdc_socket = talloc_get_type(conn->private_data, struct kdc_socket); TALLOC_FREE(conn->event.fde); rc = tstream_bsd_existing_socket(kdc_conn, socket_get_fd(conn->socket), &kdc_conn->tstream); if (rc < 0) { stream_terminate_connection(conn, "kdc_tcp_accept: out of memory"); return; } kdc_conn->conn = conn; kdc_conn->kdc_socket = kdc_socket; conn->private_data = kdc_conn; /* * The krb5 tcp pdu's has the length as 4 byte (initial_read_size), * packet_full_request_u32 provides the pdu length then. */ subreq = tstream_read_pdu_blob_send(kdc_conn, kdc_conn->conn->event.ctx, kdc_conn->tstream, 4, /* initial_read_size */ packet_full_request_u32, kdc_conn); if (subreq == NULL) { kdc_tcp_terminate_connection(kdc_conn, "kdc_tcp_accept: " "no memory for tstream_read_pdu_blob_send"); return; } tevent_req_set_callback(subreq, kdc_tcp_call_loop, kdc_conn); } static const struct stream_server_ops kdc_tcp_stream_ops = { .name = "kdc_tcp", .accept_connection = kdc_tcp_accept, .recv_handler = kdc_tcp_recv, .send_handler = kdc_tcp_send }; /* hold information about one kdc/kpasswd udp socket */ struct kdc_udp_socket { struct kdc_socket *kdc_socket; struct tdgram_context *dgram; struct tevent_queue *send_queue; }; struct kdc_udp_call { struct tsocket_address *src; DATA_BLOB in; DATA_BLOB out; }; static void kdc_udp_call_sendto_done(struct tevent_req *subreq); static void kdc_udp_call_loop(struct tevent_req *subreq) { struct kdc_udp_socket *sock = tevent_req_callback_data(subreq, struct kdc_udp_socket); struct kdc_udp_call *call; uint8_t *buf; ssize_t len; int sys_errno; bool ok; call = talloc(sock, struct kdc_udp_call); if (call == NULL) { talloc_free(call); goto done; } len = tdgram_recvfrom_recv(subreq, &sys_errno, call, &buf, &call->src); TALLOC_FREE(subreq); if (len == -1) { talloc_free(call); goto done; } call->in.data = buf; call->in.length = len; DEBUG(10,("Received krb5 UDP packet of length %lu from %s\n", (long)call->in.length, tsocket_address_string(call->src, call))); /* Call krb5 */ ok = sock->kdc_socket->process(sock->kdc_socket->kdc, call, &call->in, &call->out, call->src, sock->kdc_socket->local_address, 1 /* Datagram */); if (!ok) { talloc_free(call); goto done; } subreq = tdgram_sendto_queue_send(call, sock->kdc_socket->kdc->task->event_ctx, sock->dgram, sock->send_queue, call->out.data, call->out.length, call->src); if (subreq == NULL) { talloc_free(call); goto done; } tevent_req_set_callback(subreq, kdc_udp_call_sendto_done, call); done: subreq = tdgram_recvfrom_send(sock, sock->kdc_socket->kdc->task->event_ctx, sock->dgram); if (subreq == NULL) { task_server_terminate(sock->kdc_socket->kdc->task, "no memory for tdgram_recvfrom_send", true); return; } tevent_req_set_callback(subreq, kdc_udp_call_loop, sock); } static void kdc_udp_call_sendto_done(struct tevent_req *subreq) { struct kdc_udp_call *call = tevent_req_callback_data(subreq, struct kdc_udp_call); ssize_t ret; int sys_errno; ret = tdgram_sendto_queue_recv(subreq, &sys_errno); /* We don't care about errors */ talloc_free(call); } /* start listening on the given address */ static NTSTATUS kdc_add_socket(struct kdc_server *kdc, const struct model_ops *model_ops, const char *name, const char *address, uint16_t port, kdc_process_fn_t process) { struct kdc_socket *kdc_socket; struct kdc_udp_socket *kdc_udp_socket; struct tevent_req *udpsubreq; NTSTATUS status; int ret; kdc_socket = talloc(kdc, struct kdc_socket); NT_STATUS_HAVE_NO_MEMORY(kdc_socket); kdc_socket->kdc = kdc; kdc_socket->process = process; ret = tsocket_address_inet_from_strings(kdc_socket, "ip", address, port, &kdc_socket->local_address); if (ret != 0) { status = map_nt_error_from_unix(errno); return status; } status = stream_setup_socket(kdc->task->event_ctx, kdc->task->lp_ctx, model_ops, &kdc_tcp_stream_ops, "ip", address, &port, lpcfg_socket_options(kdc->task->lp_ctx), kdc_socket); if (!NT_STATUS_IS_OK(status)) { DEBUG(0,("Failed to bind to %s:%u TCP - %s\n", address, port, nt_errstr(status))); talloc_free(kdc_socket); return status; } kdc_udp_socket = talloc(kdc_socket, struct kdc_udp_socket); NT_STATUS_HAVE_NO_MEMORY(kdc_udp_socket); kdc_udp_socket->kdc_socket = kdc_socket; ret = tdgram_inet_udp_socket(kdc_socket->local_address, NULL, kdc_udp_socket, &kdc_udp_socket->dgram); if (ret != 0) { status = map_nt_error_from_unix(errno); DEBUG(0,("Failed to bind to %s:%u UDP - %s\n", address, port, nt_errstr(status))); return status; } kdc_udp_socket->send_queue = tevent_queue_create(kdc_udp_socket, "kdc_udp_send_queue"); NT_STATUS_HAVE_NO_MEMORY(kdc_udp_socket->send_queue); udpsubreq = tdgram_recvfrom_send(kdc_udp_socket, kdc->task->event_ctx, kdc_udp_socket->dgram); NT_STATUS_HAVE_NO_MEMORY(udpsubreq); tevent_req_set_callback(udpsubreq, kdc_udp_call_loop, kdc_udp_socket); return NT_STATUS_OK; } /* setup our listening sockets on the configured network interfaces */ static NTSTATUS kdc_startup_interfaces(struct kdc_server *kdc, struct loadparm_context *lp_ctx, struct interface *ifaces) { const struct model_ops *model_ops; int num_interfaces; TALLOC_CTX *tmp_ctx = talloc_new(kdc); NTSTATUS status; int i; /* within the kdc task we want to be a single process, so ask for the single process model ops and pass these to the stream_setup_socket() call. */ model_ops = process_model_startup(kdc->task->event_ctx, "single"); if (!model_ops) { DEBUG(0,("Can't find 'single' process model_ops\n")); return NT_STATUS_INTERNAL_ERROR; } num_interfaces = iface_count(ifaces); for (i=0; i<num_interfaces; i++) { const char *address = talloc_strdup(tmp_ctx, iface_n_ip(ifaces, i)); uint16_t kdc_port = lpcfg_krb5_port(lp_ctx); uint16_t kpasswd_port = lpcfg_kpasswd_port(lp_ctx); if (kdc_port) { status = kdc_add_socket(kdc, model_ops, "kdc", address, kdc_port, kdc_process); NT_STATUS_NOT_OK_RETURN(status); } if (kpasswd_port) { status = kdc_add_socket(kdc, model_ops, "kpasswd", address, kpasswd_port, kpasswdd_process); NT_STATUS_NOT_OK_RETURN(status); } } talloc_free(tmp_ctx); return NT_STATUS_OK; } static NTSTATUS kdc_check_generic_kerberos(struct irpc_message *msg, struct kdc_check_generic_kerberos *r) { struct PAC_Validate pac_validate; DATA_BLOB srv_sig; struct PAC_SIGNATURE_DATA kdc_sig; struct kdc_server *kdc = talloc_get_type(msg->private_data, struct kdc_server); enum ndr_err_code ndr_err; krb5_enctype etype; int ret; hdb_entry_ex ent; krb5_principal principal; krb5_keyblock keyblock; Key *key; /* There is no reply to this request */ r->out.generic_reply = data_blob(NULL, 0); ndr_err = ndr_pull_struct_blob(&r->in.generic_request, msg, &pac_validate, (ndr_pull_flags_fn_t)ndr_pull_PAC_Validate); if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { return NT_STATUS_INVALID_PARAMETER; } if (pac_validate.MessageType != 3) { /* We don't implement any other message types - such as certificate validation - yet */ return NT_STATUS_INVALID_PARAMETER; } if (pac_validate.ChecksumAndSignature.length != (pac_validate.ChecksumLength + pac_validate.SignatureLength) || pac_validate.ChecksumAndSignature.length < pac_validate.ChecksumLength || pac_validate.ChecksumAndSignature.length < pac_validate.SignatureLength ) { return NT_STATUS_INVALID_PARAMETER; } srv_sig = data_blob_const(pac_validate.ChecksumAndSignature.data, pac_validate.ChecksumLength); if (pac_validate.SignatureType == CKSUMTYPE_HMAC_MD5) { etype = ETYPE_ARCFOUR_HMAC_MD5; } else { ret = krb5_cksumtype_to_enctype(kdc->smb_krb5_context->krb5_context, pac_validate.SignatureType, &etype); if (ret != 0) { return NT_STATUS_LOGON_FAILURE; } } ret = krb5_make_principal(kdc->smb_krb5_context->krb5_context, &principal, lpcfg_realm(kdc->task->lp_ctx), "krbtgt", lpcfg_realm(kdc->task->lp_ctx), NULL); if (ret != 0) { return NT_STATUS_NO_MEMORY; } ret = kdc->config->db[0]->hdb_fetch(kdc->smb_krb5_context->krb5_context, kdc->config->db[0], principal, HDB_F_GET_KRBTGT | HDB_F_DECRYPT, &ent); if (ret != 0) { hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent); krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal); return NT_STATUS_LOGON_FAILURE; } ret = hdb_enctype2key(kdc->smb_krb5_context->krb5_context, &ent.entry, etype, &key); if (ret != 0) { hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent); krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal); return NT_STATUS_LOGON_FAILURE; } keyblock = key->key; kdc_sig.type = pac_validate.SignatureType; kdc_sig.signature = data_blob_const(&pac_validate.ChecksumAndSignature.data[pac_validate.ChecksumLength], pac_validate.SignatureLength); ret = check_pac_checksum(msg, srv_sig, &kdc_sig, kdc->smb_krb5_context->krb5_context, &keyblock); hdb_free_entry(kdc->smb_krb5_context->krb5_context, &ent); krb5_free_principal(kdc->smb_krb5_context->krb5_context, principal); if (ret != 0) { return NT_STATUS_LOGON_FAILURE; } return NT_STATUS_OK; } /* startup the kdc task */ static void kdc_task_init(struct task_server *task) { struct kdc_server *kdc; NTSTATUS status; krb5_error_code ret; struct interface *ifaces; switch (lpcfg_server_role(task->lp_ctx)) { case ROLE_STANDALONE: task_server_terminate(task, "kdc: no KDC required in standalone configuration", false); return; case ROLE_DOMAIN_MEMBER: task_server_terminate(task, "kdc: no KDC required in member server configuration", false); return; case ROLE_DOMAIN_CONTROLLER: /* Yes, we want a KDC */ break; } load_interfaces(task, lpcfg_interfaces(task->lp_ctx), &ifaces); if (iface_count(ifaces) == 0) { task_server_terminate(task, "kdc: no network interfaces configured", false); return; } task_server_set_title(task, "task[kdc]"); kdc = talloc(task, struct kdc_server); if (kdc == NULL) { task_server_terminate(task, "kdc: out of memory", true); return; } kdc->task = task; initialize_krb5_error_table(); ret = smb_krb5_init_context(kdc, task->event_ctx, task->lp_ctx, &kdc->smb_krb5_context); if (ret) { DEBUG(1,("kdc_task_init: krb5_init_context failed (%s)\n", error_message(ret))); task_server_terminate(task, "kdc: krb5_init_context failed", true); return; } krb5_add_et_list(kdc->smb_krb5_context->krb5_context, initialize_hdb_error_table_r); ret = krb5_kdc_get_config(kdc->smb_krb5_context->krb5_context, &kdc->config); if(ret) { task_server_terminate(task, "kdc: failed to get KDC configuration", true); return; } kdc->config->logf = kdc->smb_krb5_context->logf; kdc->config->db = talloc(kdc, struct HDB *); if (!kdc->config->db) { task_server_terminate(task, "kdc: out of memory", true); return; } kdc->config->num_db = 1; /* Register hdb-samba4 hooks for use as a keytab */ kdc->base_ctx = talloc_zero(kdc, struct samba_kdc_base_context); if (!kdc->base_ctx) { task_server_terminate(task, "kdc: out of memory", true); return; } kdc->base_ctx->ev_ctx = task->event_ctx; kdc->base_ctx->lp_ctx = task->lp_ctx; status = hdb_samba4_create_kdc(kdc->base_ctx, kdc->smb_krb5_context->krb5_context, &kdc->config->db[0]); if (!NT_STATUS_IS_OK(status)) { task_server_terminate(task, "kdc: hdb_samba4_create_kdc (setup KDC database) failed", true); return; } ret = krb5_plugin_register(kdc->smb_krb5_context->krb5_context, PLUGIN_TYPE_DATA, "hdb", &hdb_samba4); if(ret) { task_server_terminate(task, "kdc: failed to register hdb plugin", true); return; } ret = krb5_kt_register(kdc->smb_krb5_context->krb5_context, &hdb_kt_ops); if(ret) { task_server_terminate(task, "kdc: failed to register keytab plugin", true); return; } /* Register WinDC hooks */ ret = krb5_plugin_register(kdc->smb_krb5_context->krb5_context, PLUGIN_TYPE_DATA, "windc", &windc_plugin_table); if(ret) { task_server_terminate(task, "kdc: failed to register windc plugin", true); return; } krb5_kdc_windc_init(kdc->smb_krb5_context->krb5_context); /* start listening on the configured network interfaces */ status = kdc_startup_interfaces(kdc, task->lp_ctx, ifaces); if (!NT_STATUS_IS_OK(status)) { task_server_terminate(task, "kdc failed to setup interfaces", true); return; } status = IRPC_REGISTER(task->msg_ctx, irpc, KDC_CHECK_GENERIC_KERBEROS, kdc_check_generic_kerberos, kdc); if (!NT_STATUS_IS_OK(status)) { task_server_terminate(task, "nbtd failed to setup monitoring", true); return; } irpc_add_name(task->msg_ctx, "kdc_server"); } /* called at smbd startup - register ourselves as a server service */ NTSTATUS server_service_kdc_init(void) { return register_server_service("kdc", kdc_task_init); }