/* Unix SMB/CIFS implementation. a composite API for finding a DC and its name Copyright (C) Volker Lendecke 2005 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2006 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 "include/includes.h" #include "lib/messaging/irpc.h" #include "librpc/gen_ndr/ndr_irpc.h" #include "librpc/gen_ndr/samr.h" #include "libcli/composite/composite.h" #include "libcli/libcli.h" #include "libcli/resolve/resolve.h" struct finddcs_state { struct composite_context *ctx; struct messaging_context *msg_ctx; const char *domain_name; struct dom_sid *domain_sid; struct nbtd_getdcname r; struct nbt_name_status node_status; int num_dcs; struct nbt_dc_name *dcs; }; static void finddcs_name_resolved(struct composite_context *ctx); static void finddcs_getdc_replied(struct irpc_request *ireq); static void fallback_node_status(struct finddcs_state *state); static void fallback_node_status_replied(struct nbt_name_request *name_req); /* * Setup and send off the a normal name resolution for the target name. * * The domain_sid parameter is optional, and is used in the subsequent getdc request. * * This will try a GetDC request, but this may not work. It will try * a node status as a fallback, then return no name (but still include * the IP) */ struct composite_context *finddcs_send(TALLOC_CTX *mem_ctx, const char *domain_name, int name_type, struct dom_sid *domain_sid, const char **methods, struct event_context *event_ctx, struct messaging_context *msg_ctx) { struct composite_context *c, *creq; struct finddcs_state *state; struct nbt_name name; c = composite_create(mem_ctx, event_ctx); if (c == NULL) return NULL; state = talloc(c, struct finddcs_state); if (composite_nomem(state, c)) return c; c->private_data = state; state->ctx = c; state->domain_name = talloc_strdup(state, domain_name); if (composite_nomem(state->domain_name, c)) return c; if (domain_sid) { state->domain_sid = talloc_reference(state, domain_sid); if (composite_nomem(state->domain_sid, c)) return c; } else { state->domain_sid = NULL; } state->msg_ctx = msg_ctx; make_nbt_name(&name, state->domain_name, name_type); creq = resolve_name_send(&name, event_ctx, methods); composite_continue(c, creq, finddcs_name_resolved, state); return c; } /* Having got an name query answer, fire off a GetDC request, so we * can find the target's all-important name. (Kerberos and some * netlogon operations are quite picky about names) * * The name is a courtesy, if we don't find it, don't completely fail. * * However, if the nbt server is down, fall back to a node status * request */ static void finddcs_name_resolved(struct composite_context *ctx) { struct finddcs_state *state = talloc_get_type(ctx->async.private_data, struct finddcs_state); struct irpc_request *ireq; struct server_id *nbt_servers; const char *address; state->ctx->status = resolve_name_recv(ctx, state, &address); if (!composite_is_ok(state->ctx)) return; state->num_dcs = 1; state->dcs = talloc_array(state, struct nbt_dc_name, state->num_dcs); if (composite_nomem(state->dcs, state->ctx)) return; state->dcs[0].address = talloc_steal(state->dcs, address); /* Try and find the nbt server. Fallback to a node status * request if we can't make this happen The nbt server just * might not be running, or we may not have a messaging * context (not root etc) */ if (!state->msg_ctx) { fallback_node_status(state); return; } nbt_servers = irpc_servers_byname(state->msg_ctx, "nbt_server"); if ((nbt_servers == NULL) || (nbt_servers[0].id == 0)) { fallback_node_status(state); return; } state->r.in.domainname = state->domain_name; state->r.in.ip_address = state->dcs[0].address; state->r.in.my_computername = lp_netbios_name(); state->r.in.my_accountname = talloc_asprintf(state, "%s$", lp_netbios_name()); if (composite_nomem(state->r.in.my_accountname, state->ctx)) return; state->r.in.account_control = ACB_WSTRUST; state->r.in.domain_sid = state->domain_sid; ireq = irpc_call_send(state->msg_ctx, nbt_servers[0], &dcerpc_table_irpc, DCERPC_NBTD_GETDCNAME, &state->r, state); if (!ireq) { fallback_node_status(state); return; } composite_continue_irpc(state->ctx, ireq, finddcs_getdc_replied, state); } /* Called when the GetDC request returns */ static void finddcs_getdc_replied(struct irpc_request *ireq) { struct finddcs_state *state = talloc_get_type(ireq->async.private, struct finddcs_state); state->ctx->status = irpc_call_recv(ireq); if (!composite_is_ok(state->ctx)) return; state->dcs[0].name = talloc_steal(state->dcs, state->r.out.dcname); composite_done(state->ctx); } /* The GetDC request might not be availible (such as occours when the * NBT server is down). Fallback to a node status. It is the best * hope we have... */ static void fallback_node_status(struct finddcs_state *state) { struct nbt_name_socket *nbtsock; struct nbt_name_request *name_req; state->node_status.in.name.name = "*"; state->node_status.in.name.type = NBT_NAME_CLIENT; state->node_status.in.name.scope = NULL; state->node_status.in.dest_addr = state->dcs[0].address; state->node_status.in.timeout = 1; state->node_status.in.retries = 2; nbtsock = nbt_name_socket_init(state, state->ctx->event_ctx); if (composite_nomem(nbtsock, state->ctx)) return; name_req = nbt_name_status_send(nbtsock, &state->node_status); if (composite_nomem(name_req, state->ctx)) return; composite_continue_nbt(state->ctx, name_req, fallback_node_status_replied, state); } /* We have a node status reply (or perhaps a timeout) */ static void fallback_node_status_replied(struct nbt_name_request *name_req) { int i; struct finddcs_state *state = talloc_get_type(name_req->async.private, struct finddcs_state); state->ctx->status = nbt_name_status_recv(name_req, state, &state->node_status); if (!composite_is_ok(state->ctx)) return; for (i=0; i < state->node_status.out.status.num_names; i++) { int j; if (state->node_status.out.status.names[i].type == NBT_NAME_SERVER) { char *name = talloc_strndup(state->dcs, state->node_status.out.status.names[0].name, 15); /* Strip space padding */ if (name) { j = MIN(strlen(name), 15); for (; j > 0 && name[j - 1] == ' '; j--) { name[j - 1] = '\0'; } } state->dcs[0].name = name; composite_done(state->ctx); return; } } composite_error(state->ctx, NT_STATUS_NO_LOGON_SERVERS); } NTSTATUS finddcs_recv(struct composite_context *c, TALLOC_CTX *mem_ctx, int *num_dcs, struct nbt_dc_name **dcs) { NTSTATUS status = composite_wait(c); if (NT_STATUS_IS_OK(status)) { struct finddcs_state *state = talloc_get_type(c->private_data, struct finddcs_state); *num_dcs = state->num_dcs; *dcs = talloc_steal(mem_ctx, state->dcs); } talloc_free(c); return status; } NTSTATUS finddcs(TALLOC_CTX *mem_ctx, const char *domain_name, int name_type, struct dom_sid *domain_sid, const char **methods, struct event_context *event_ctx, struct messaging_context *msg_ctx, int *num_dcs, struct nbt_dc_name **dcs) { struct composite_context *c = finddcs_send(mem_ctx, domain_name, name_type, domain_sid, methods, event_ctx, msg_ctx); return finddcs_recv(c, mem_ctx, num_dcs, dcs); }