/* Unix SMB/CIFS implementation. KDC Server startup Copyright (C) Andrew Bartlett 2005 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 2 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, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "includes.h" #include "smbd/service_task.h" #include "smbd/service_stream.h" #include "lib/events/events.h" #include "lib/socket/socket.h" #include "kdc/kdc.h" #include "system/network.h" #include "dlinklist.h" #include "lib/messaging/irpc.h" /* hold all the info needed to send a reply */ struct kdc_reply { struct kdc_reply *next, *prev; const char *dest_address; int dest_port; DATA_BLOB packet; }; /* top level context structure for the kdc server */ struct kdc_server { struct task_server *task; krb5_kdc_configuration *config; struct smb_krb5_context *smb_krb5_context; }; /* hold information about one kdc socket */ struct kdc_socket { struct socket_context *sock; struct kdc_server *kdc; struct fd_event *fde; /* a queue of outgoing replies that have been deferred */ struct kdc_reply *send_queue; int (*process)(krb5_context context, krb5_kdc_configuration *config, unsigned char *buf, size_t len, krb5_data *reply, const char *from, struct sockaddr *addr); }; /* 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_server *kdc; /* the partial data we've receiced yet */ DATA_BLOB partial; /* the amount that we used yet from the partial buffer */ uint32_t partial_read; /* prevent loops when we use half async code, while processing a requuest */ BOOL processing; /* a queue of outgoing replies that have been deferred */ struct data_blob_list_item *send_queue; int (*process)(krb5_context context, krb5_kdc_configuration *config, unsigned char *buf, size_t len, krb5_data *reply, const char *from, struct sockaddr *addr); }; /* handle fd send events on a KDC socket */ static void kdc_send_handler(struct kdc_socket *kdc_socket) { while (kdc_socket->send_queue) { struct kdc_reply *rep = kdc_socket->send_queue; NTSTATUS status; size_t sendlen; status = socket_sendto(kdc_socket->sock, &rep->packet, &sendlen, 0, rep->dest_address, rep->dest_port); if (NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) { break; } DLIST_REMOVE(kdc_socket->send_queue, rep); talloc_free(rep); } if (kdc_socket->send_queue == NULL) { EVENT_FD_NOT_WRITEABLE(kdc_socket->fde); } } /* handle fd recv events on a KDC socket */ static void kdc_recv_handler(struct kdc_socket *kdc_socket) { NTSTATUS status; TALLOC_CTX *tmp_ctx = talloc_new(kdc_socket); DATA_BLOB blob; struct kdc_reply *rep; krb5_data reply; size_t nread, dsize; const char *src_addr; int src_port; struct sockaddr_in src_sock_addr; struct ipv4_addr addr; int ret; status = socket_pending(kdc_socket->sock, &dsize); if (!NT_STATUS_IS_OK(status)) { talloc_free(tmp_ctx); return; } blob = data_blob_talloc(kdc_socket, NULL, dsize); if (blob.data == NULL) { /* hope this is a temporary low memory condition */ talloc_free(tmp_ctx); return; } status = socket_recvfrom(kdc_socket->sock, blob.data, blob.length, &nread, 0, &src_addr, &src_port); if (!NT_STATUS_IS_OK(status)) { talloc_free(tmp_ctx); return; } talloc_steal(tmp_ctx, src_addr); blob.length = nread; DEBUG(2,("Received krb5 UDP packet of length %u from %s:%u\n", blob.length, src_addr, (uint16_t)src_port)); /* TODO: This really should be in a utility function somewhere */ ZERO_STRUCT(src_sock_addr); #ifdef HAVE_SOCK_SIN_LEN src_sock_addr.sin_len = sizeof(src_sock_addr); #endif addr = interpret_addr2(src_addr); src_sock_addr.sin_addr.s_addr = addr.addr; src_sock_addr.sin_port = htons(src_port); src_sock_addr.sin_family = PF_INET; /* Call krb5 */ ret = kdc_socket->process(kdc_socket->kdc->smb_krb5_context->krb5_context, kdc_socket->kdc->config, blob.data, blob.length, &reply, src_addr, (struct sockaddr *)&src_sock_addr); if (ret == -1) { talloc_free(tmp_ctx); return; } /* queue a pending reply */ rep = talloc(kdc_socket, struct kdc_reply); if (rep == NULL) { krb5_data_free(&reply); talloc_free(tmp_ctx); return; } rep->dest_address = talloc_steal(rep, src_addr); rep->dest_port = src_port; rep->packet = data_blob_talloc(rep, reply.data, reply.length); krb5_data_free(&reply); if (rep->packet.data == NULL) { talloc_free(rep); talloc_free(tmp_ctx); return; } DLIST_ADD_END(kdc_socket->send_queue, rep, struct kdc_reply *); EVENT_FD_WRITEABLE(kdc_socket->fde); talloc_free(tmp_ctx); } /* handle fd events on a KDC socket */ static void kdc_socket_handler(struct event_context *ev, struct fd_event *fde, uint16_t flags, void *private) { struct kdc_socket *kdc_socket = talloc_get_type(private, struct kdc_socket); if (flags & EVENT_FD_WRITE) { kdc_send_handler(kdc_socket); } if (flags & EVENT_FD_READ) { kdc_recv_handler(kdc_socket); } } static void kdc_tcp_terminate_connection(struct kdc_tcp_connection *kdcconn, const char *reason) { stream_terminate_connection(kdcconn->conn, reason); } /* called when we get a new connection */ static void kdc_tcp_accept(struct stream_connection *conn) { struct kdc_server *kdc = talloc_get_type(conn->private, struct kdc_server); struct kdc_tcp_connection *kdcconn; kdcconn = talloc_zero(conn, struct kdc_tcp_connection); if (!kdcconn) { stream_terminate_connection(conn, "kdc_tcp_accept: out of memory"); return; } kdcconn->conn = conn; kdcconn->kdc = kdc; kdcconn->process = krb5_kdc_process_krb5_request; conn->private = kdcconn; } /* receive some data on a KDC connection */ static void kdc_tcp_recv(struct stream_connection *conn, uint16_t flags) { struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private, struct kdc_tcp_connection); NTSTATUS status = NT_STATUS_UNSUCCESSFUL; TALLOC_CTX *tmp_ctx = talloc_new(kdcconn); struct data_blob_list_item *rep; krb5_data reply; size_t nread; const char *src_addr; int src_port; struct sockaddr_in src_sock_addr; struct ipv4_addr addr; int ret; /* avoid recursion, because of half async code */ if (kdcconn->processing) { EVENT_FD_NOT_READABLE(conn->event.fde); return; } if (kdcconn->partial.length == 0) { kdcconn->partial = data_blob_talloc(kdcconn, NULL, 4); if (!kdcconn->partial.data) goto nomem; kdcconn->partial_read = 0; } /* read in the packet length */ if (kdcconn->partial_read < 4) { uint32_t packet_length; status = socket_recv(conn->socket, kdcconn->partial.data + kdcconn->partial_read, 4 - kdcconn->partial_read, &nread, 0); if (NT_STATUS_IS_ERR(status)) goto failed; if (!NT_STATUS_IS_OK(status)) return; kdcconn->partial_read += nread; if (kdcconn->partial_read != 4) return; packet_length = RIVAL(kdcconn->partial.data, 0) + 4; kdcconn->partial.data = talloc_realloc(kdcconn, kdcconn->partial.data, uint8_t, packet_length); if (!kdcconn->partial.data) goto nomem; kdcconn->partial.length = packet_length; } /* read in the body */ status = socket_recv(conn->socket, kdcconn->partial.data + kdcconn->partial_read, kdcconn->partial.length - kdcconn->partial_read, &nread, 0); if (NT_STATUS_IS_ERR(status)) goto failed; if (!NT_STATUS_IS_OK(status)) return; kdcconn->partial_read += nread; if (kdcconn->partial_read != kdcconn->partial.length) return; /* * we have parsed the request, so we can reset the kdcconn->partial_read, * maybe we could also free kdcconn->partial, but for now we keep it, * and overwrite it the next time */ kdcconn->partial_read = 0; src_addr = socket_get_peer_addr(kdcconn->conn->socket, tmp_ctx); if (!src_addr) goto nomem; src_port = socket_get_peer_port(kdcconn->conn->socket); DEBUG(2,("Received krb5 TCP packet of length %u from %s:%u\n", kdcconn->partial.length - 4, src_addr, src_port)); /* TODO: This really should be in a utility function somewhere */ ZERO_STRUCT(src_sock_addr); #ifdef HAVE_SOCK_SIN_LEN src_sock_addr.sin_len = sizeof(src_sock_addr); #endif addr = interpret_addr2(src_addr); src_sock_addr.sin_addr.s_addr = addr.addr; src_sock_addr.sin_port = htons(src_port); src_sock_addr.sin_family = PF_INET; /* Call krb5 */ kdcconn->processing = True; ret = kdcconn->process(kdcconn->kdc->smb_krb5_context->krb5_context, kdcconn->kdc->config, kdcconn->partial.data + 4, kdcconn->partial.length - 4, &reply, src_addr, (struct sockaddr *)&src_sock_addr); kdcconn->processing = False; if (ret == -1) { status = NT_STATUS_INTERNAL_ERROR; goto failed; } /* and now encode the reply */ rep = talloc(kdcconn, struct data_blob_list_item); if (!rep) { krb5_data_free(&reply); goto nomem; } rep->blob = data_blob_talloc(rep, NULL, reply.length + 4); if (!rep->blob.data) { krb5_data_free(&reply); goto nomem; } RSIVAL(rep->blob.data, 0, reply.length); memcpy(rep->blob.data + 4, reply.data, reply.length); krb5_data_free(&reply); if (!kdcconn->send_queue) { EVENT_FD_WRITEABLE(kdcconn->conn->event.fde); } DLIST_ADD_END(kdcconn->send_queue, rep, struct data_blob_list_item *); EVENT_FD_READABLE(kdcconn->conn->event.fde); /* the call isn't needed any more */ talloc_free(tmp_ctx); return; nomem: status = NT_STATUS_NO_MEMORY; failed: kdc_tcp_terminate_connection(kdcconn, nt_errstr(status)); } /* called when we can write to a connection */ static void kdc_tcp_send(struct stream_connection *conn, uint16_t flags) { struct kdc_tcp_connection *kdcconn = talloc_get_type(conn->private, struct kdc_tcp_connection); NTSTATUS status; while (kdcconn->send_queue) { struct data_blob_list_item *q = kdcconn->send_queue; size_t sendlen; status = socket_send(conn->socket, &q->blob, &sendlen, 0); if (NT_STATUS_IS_ERR(status)) goto failed; if (!NT_STATUS_IS_OK(status)) return; q->blob.length -= sendlen; q->blob.data += sendlen; if (q->blob.length == 0) { DLIST_REMOVE(kdcconn->send_queue, q); talloc_free(q); } } EVENT_FD_NOT_WRITEABLE(conn->event.fde); return; failed: kdc_tcp_terminate_connection(kdcconn, nt_errstr(status)); } 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 }; /* start listening on the given address */ static NTSTATUS kdc_add_socket(struct kdc_server *kdc, const char *address) { const struct model_ops *model_ops; struct kdc_socket *kdc_socket; NTSTATUS status; uint16_t port = lp_krb5_port(); kdc_socket = talloc(kdc, struct kdc_socket); NT_STATUS_HAVE_NO_MEMORY(kdc_socket); status = socket_create("ip", SOCKET_TYPE_DGRAM, &kdc_socket->sock, 0); if (!NT_STATUS_IS_OK(status)) { talloc_free(kdc_socket); return status; } kdc_socket->kdc = kdc; kdc_socket->send_queue = NULL; kdc_socket->process = krb5_kdc_process_krb5_request; talloc_steal(kdc_socket, kdc_socket->sock); kdc_socket->fde = event_add_fd(kdc->task->event_ctx, kdc, socket_get_fd(kdc_socket->sock), EVENT_FD_READ, kdc_socket_handler, kdc_socket); status = socket_listen(kdc_socket->sock, address, port, 0, 0); if (!NT_STATUS_IS_OK(status)) { DEBUG(0,("Failed to bind to %s:%d UDP - %s\n", address, port, nt_errstr(status))); talloc_free(kdc_socket); return status; } /* 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_byname("single"); if (!model_ops) { DEBUG(0,("Can't find 'single' process model_ops\n")); talloc_free(kdc_socket); return NT_STATUS_INTERNAL_ERROR; } status = stream_setup_socket(kdc->task->event_ctx, model_ops, &kdc_tcp_stream_ops, "ip", address, &port, kdc); 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; } return NT_STATUS_OK; } /* setup our listening sockets on the configured network interfaces */ static NTSTATUS kdc_startup_interfaces(struct kdc_server *kdc) { int num_interfaces = iface_count(); TALLOC_CTX *tmp_ctx = talloc_new(kdc); NTSTATUS status; /* if we are allowing incoming packets from any address, then we need to bind to the wildcard address */ if (!lp_bind_interfaces_only()) { status = kdc_add_socket(kdc, "0.0.0.0"); NT_STATUS_NOT_OK_RETURN(status); } else { int i; for (i=0; itask = task; /* Setup the KDC configuration */ kdc->config = talloc(kdc, krb5_kdc_configuration); if (!kdc->config) { task_server_terminate(task, "kdc: out of memory"); return; } krb5_kdc_default_config(kdc->config); /* NAT and the like make this pointless, and painful */ kdc->config->check_ticket_addresses = FALSE; initialize_krb5_error_table(); ret = smb_krb5_init_context(kdc, &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"); return; } krb5_add_et_list(kdc->smb_krb5_context->krb5_context, initialize_hdb_error_table_r); kdc->config->logf = kdc->smb_krb5_context->logf; kdc->config->db = talloc(kdc->config, struct HDB *); if (!kdc->config->db) { task_server_terminate(task, "kdc: out of memory"); return; } kdc->config->num_db = 1; ret = hdb_ldb_create(kdc, kdc->smb_krb5_context->krb5_context, &kdc->config->db[0], lp_sam_url()); if (ret != 0) { DEBUG(1, ("kdc_task_init: hdb_ldb_create fails: %s\n", smb_get_krb5_error_message(kdc->smb_krb5_context->krb5_context, ret, kdc))); task_server_terminate(task, "kdc: hdb_ldb_create failed"); return; } /* start listening on the configured network interfaces */ status = kdc_startup_interfaces(kdc); if (!NT_STATUS_IS_OK(status)) { task_server_terminate(task, "kdc failed to setup interfaces"); return; } irpc_add_name(task->msg_ctx, "kdc_server"); } /* called on startup of the KDC service */ static NTSTATUS kdc_init(struct event_context *event_ctx, const struct model_ops *model_ops) { return task_server_startup(event_ctx, model_ops, kdc_task_init); } /* called at smbd startup - register ourselves as a server service */ NTSTATUS server_service_kdc_init(void) { return register_server_service("kdc", kdc_init); }