2 Unix SMB/CIFS implementation.
4 general name resolution interface
6 Copyright (C) Andrew Tridgell 2005
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include "lib/events/events.h"
24 #include "libcli/composite/composite.h"
25 #include "libcli/resolve/resolve.h"
26 #include "librpc/gen_ndr/ndr_nbt.h"
28 struct resolve_state {
31 struct composite_context *creq;
32 const char *reply_addr;
35 static struct composite_context *setup_next_method(struct composite_context *c);
37 /* pointers to the resolver backends */
38 static const struct resolve_method {
40 struct composite_context *(*send_fn)(TALLOC_CTX *mem_ctx, struct event_context *, struct nbt_name *);
41 NTSTATUS (*recv_fn)(struct composite_context *, TALLOC_CTX *, const char **);
43 } resolve_methods[] = {
44 { "bcast", resolve_name_bcast_send, resolve_name_bcast_recv },
45 { "wins", resolve_name_wins_send, resolve_name_wins_recv },
46 { "host", resolve_name_host_send, resolve_name_host_recv }
51 find a matching backend
53 static const struct resolve_method *find_method(const char *name)
56 if (name == NULL) return NULL;
57 for (i=0;i<ARRAY_SIZE(resolve_methods);i++) {
58 if (strcasecmp(name, resolve_methods[i].name) == 0) {
59 return &resolve_methods[i];
66 handle completion of one name resolve method
68 static void resolve_handler(struct composite_context *creq)
70 struct composite_context *c = (struct composite_context *)creq->async.private_data;
71 struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
72 const struct resolve_method *method = find_method(state->methods[0]);
74 c->status = method->recv_fn(creq, state, &state->reply_addr);
76 if (!NT_STATUS_IS_OK(c->status)) {
78 state->creq = setup_next_method(c);
79 if (state->creq != NULL) {
84 if (!NT_STATUS_IS_OK(c->status)) {
85 c->state = COMPOSITE_STATE_ERROR;
87 c->state = COMPOSITE_STATE_DONE;
95 static struct composite_context *setup_next_method(struct composite_context *c)
97 struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
98 struct composite_context *creq = NULL;
101 const struct resolve_method *method = find_method(state->methods[0]);
103 creq = method->send_fn(c, c->event_ctx, &state->name);
105 if (creq == NULL && state->methods[0]) state->methods++;
107 } while (!creq && state->methods[0]);
110 creq->async.fn = resolve_handler;
111 creq->async.private_data = c;
118 general name resolution - async send
120 struct composite_context *resolve_name_send(struct nbt_name *name, struct event_context *event_ctx,
121 const char **methods)
123 struct composite_context *c;
124 struct resolve_state *state;
126 c = composite_create(event_ctx, event_ctx);
127 if (c == NULL) return NULL;
129 if (methods == NULL) {
130 composite_error(c, NT_STATUS_INVALID_PARAMETER);
134 if (event_ctx == NULL) {
135 c->event_ctx = event_context_init(c);
137 c->event_ctx = talloc_reference(c, event_ctx);
139 if (composite_nomem(c->event_ctx, c)) return c;
141 state = talloc(c, struct resolve_state);
142 if (composite_nomem(state, c)) return c;
143 c->private_data = state;
145 c->status = nbt_name_dup(state, name, &state->name);
146 if (!composite_is_ok(c)) return c;
148 state->methods = str_list_copy(state, methods);
149 if (composite_nomem(state->methods, c)) return c;
151 if (is_ipaddress(state->name.name) ||
152 strcasecmp(state->name.name, "localhost") == 0) {
153 struct ipv4_addr ip = interpret_addr2(state->name.name);
154 state->reply_addr = talloc_strdup(state, sys_inet_ntoa(ip));
155 if (composite_nomem(state->reply_addr, c)) return c;
160 state->creq = setup_next_method(c);
161 if (composite_nomem(state->creq, c)) return c;
167 general name resolution method - recv side
169 NTSTATUS resolve_name_recv(struct composite_context *c,
170 TALLOC_CTX *mem_ctx, const char **reply_addr)
174 status = composite_wait(c);
176 if (NT_STATUS_IS_OK(status)) {
177 struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
178 *reply_addr = talloc_steal(mem_ctx, state->reply_addr);
186 general name resolution - sync call
188 NTSTATUS resolve_name(struct nbt_name *name, TALLOC_CTX *mem_ctx, const char **reply_addr,
189 struct event_context *ev)
191 struct composite_context *c = resolve_name_send(name, ev,
192 lp_name_resolve_order());
193 return resolve_name_recv(c, mem_ctx, reply_addr);
196 /* Initialise a struct nbt_name with a NULL scope */
198 void make_nbt_name(struct nbt_name *nbt, const char *name, int type)
205 /* Initialise a struct nbt_name with a NBT_NAME_CLIENT (0x00) name */
207 void make_nbt_name_client(struct nbt_name *nbt, const char *name)
209 make_nbt_name(nbt, name, NBT_NAME_CLIENT);
212 /* Initialise a struct nbt_name with a NBT_NAME_SERVER (0x20) name */
214 void make_nbt_name_server(struct nbt_name *nbt, const char *name)
216 make_nbt_name(nbt, name, NBT_NAME_SERVER);