source4/libcli/resolve/resolve.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    general name resolution interface
   5
   6    Copyright (C) Andrew Tridgell 2005
   7    Copyright (C) Jelmer Vernooij 2007
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "libcli/composite/composite.h"
  25 #include "libcli/resolve/resolve.h"
  26 #include "librpc/gen_ndr/ndr_nbt.h"
  27 #include "system/network.h"
  28 #include "lib/socket/socket.h"
  29 #include "../lib/util/dlinklist.h"
  30 #include "lib/tsocket/tsocket.h"
  31 #include "lib/util/util_net.h"
  32
  33 struct resolve_state {
  34         struct resolve_context *ctx;
  35         struct resolve_method *method;
  36         uint32_t flags;
  37         uint16_t port;
  38         struct nbt_name name;
  39         struct composite_context *creq;
  40         struct socket_address **addrs;
  41         char **names;
  42 };
  43
  44 static struct composite_context *setup_next_method(struct composite_context *c);
  45
  46
  47 struct resolve_context {
  48         struct resolve_method {
  49                 resolve_name_send_fn send_fn;
  50                 resolve_name_recv_fn recv_fn;
  51                 void *privdata;
  52                 struct resolve_method *prev, *next;
  53         } *methods;
  54 };
  55
  56 /**
  57  * Initialize a resolve context
  58  */
  59 struct resolve_context *resolve_context_init(TALLOC_CTX *mem_ctx)
  60 {
  61         return talloc_zero(mem_ctx, struct resolve_context);
  62 }
  63
  64 /**
  65  * Add a resolve method
  66  */
  67 bool resolve_context_add_method(struct resolve_context *ctx, resolve_name_send_fn send_fn,
  68                                 resolve_name_recv_fn recv_fn, void *userdata)
  69 {
  70         struct resolve_method *method = talloc_zero(ctx, struct resolve_method);
  71
  72         if (method == NULL)
  73                 return false;
  74
  75         method->send_fn = send_fn;
  76         method->recv_fn = recv_fn;
  77         method->privdata = userdata;
  78         DLIST_ADD_END(ctx->methods, method, struct resolve_method *);
  79         return true;
  80 }
  81
  82 /**
  83   handle completion of one name resolve method
  84 */
  85 static void resolve_handler(struct composite_context *creq)
  86 {
  87         struct composite_context *c = (struct composite_context *)creq->async.private_data;
  88         struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
  89         const struct resolve_method *method = state->method;
  90
  91         c->status = method->recv_fn(creq, state, &state->addrs, &state->names);
  92
  93         if (!NT_STATUS_IS_OK(c->status)) {
  94                 state->method = state->method->next;
  95                 state->creq = setup_next_method(c);
  96                 if (state->creq != NULL) {
  97                         return;
  98                 }
  99         }
 100
 101         if (!NT_STATUS_IS_OK(c->status)) {
 102                 c->state = COMPOSITE_STATE_ERROR;
 103         } else {
 104                 c->state = COMPOSITE_STATE_DONE;
 105         }
 106         if (c->async.fn) {
 107                 c->async.fn(c);
 108         }
 109 }
 110
 111
 112 static struct composite_context *setup_next_method(struct composite_context *c)
 113 {
 114         struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
 115         struct composite_context *creq = NULL;
 116
 117         do {
 118                 if (state->method) {
 119                         creq = state->method->send_fn(c, c->event_ctx,
 120                                                       state->method->privdata,
 121                                                       state->flags,
 122                                                       state->port,
 123                                                       &state->name);
 124                 }
 125                 if (creq == NULL && state->method) state->method = state->method->next;
 126
 127         } while (!creq && state->method);
 128
 129         if (creq) {
 130                 creq->async.fn = resolve_handler;
 131                 creq->async.private_data = c;
 132         }
 133
 134         return creq;
 135 }
 136
 137 /*
 138   general name resolution - async send
 139  */
 140 struct composite_context *resolve_name_all_send(struct resolve_context *ctx,
 141                                                 TALLOC_CTX *mem_ctx,
 142                                                 uint32_t flags,
 143                                                 uint16_t port,
 144                                                 struct nbt_name *name,
 145                                                 struct tevent_context *event_ctx)
 146 {
 147         struct composite_context *c;
 148         struct resolve_state *state;
 149
 150         if (event_ctx == NULL) {
 151                 return NULL;
 152         }
 153
 154         c = composite_create(mem_ctx, event_ctx);
 155         if (c == NULL) return NULL;
 156
 157         if (composite_nomem(c->event_ctx, c)) return c;
 158
 159         state = talloc(c, struct resolve_state);
 160         if (composite_nomem(state, c)) return c;
 161         c->private_data = state;
 162
 163         state->flags = flags;
 164         state->port = port;
 165
 166         c->status = nbt_name_dup(state, name, &state->name);
 167         if (!composite_is_ok(c)) return c;
 168
 169         state->ctx = talloc_reference(state, ctx);
 170         if (composite_nomem(state->ctx, c)) return c;
 171
 172         if (is_ipaddress(state->name.name) ||
 173             strcasecmp(state->name.name, "localhost") == 0) {
 174                 struct in_addr ip = interpret_addr2(state->name.name);
 175
 176                 state->addrs = talloc_array(state, struct socket_address *, 2);
 177                 if (composite_nomem(state->addrs, c)) return c;
 178                 state->addrs[0] = socket_address_from_strings(state->addrs, "ipv4",
 179                                                               inet_ntoa(ip), 0);
 180                 if (composite_nomem(state->addrs[0], c)) return c;
 181                 state->addrs[1] = NULL;
 182                 state->names = talloc_array(state, char *, 2);
 183                 if (composite_nomem(state->names, c)) return c;
 184                 state->names[0] = talloc_strdup(state->names, state->name.name);
 185                 if (composite_nomem(state->names[0], c)) return c;
 186                 state->names[1] = NULL;
 187                 composite_done(c);
 188                 return c;
 189         }
 190
 191         state->method = ctx->methods;
 192         if (state->method == NULL) {
 193                 composite_error(c, NT_STATUS_BAD_NETWORK_NAME);
 194                 return c;
 195         }
 196         state->creq = setup_next_method(c);
 197         if (composite_nomem(state->creq, c)) return c;
 198
 199         return c;
 200 }
 201
 202 /*
 203   general name resolution method - recv side
 204  */
 205 NTSTATUS resolve_name_all_recv(struct composite_context *c,
 206                                TALLOC_CTX *mem_ctx,
 207                                struct socket_address ***addrs,
 208                                char ***names)
 209 {
 210         NTSTATUS status;
 211
 212         status = composite_wait(c);
 213
 214         if (NT_STATUS_IS_OK(status)) {
 215                 struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
 216                 *addrs = talloc_steal(mem_ctx, state->addrs);
 217                 if (names) {
 218                         *names = talloc_steal(mem_ctx, state->names);
 219                 }
 220         }
 221
 222         talloc_free(c);
 223         return status;
 224 }
 225
 226 struct composite_context *resolve_name_send(struct resolve_context *ctx,
 227                                             TALLOC_CTX *mem_ctx,
 228                                             struct nbt_name *name,
 229                                             struct tevent_context *event_ctx)
 230 {
 231         return resolve_name_all_send(ctx, mem_ctx, 0, 0, name, event_ctx);
 232 }
 233
 234 NTSTATUS resolve_name_recv(struct composite_context *c,
 235                            TALLOC_CTX *mem_ctx,
 236                            const char **reply_addr)
 237 {
 238         NTSTATUS status;
 239         struct socket_address **addrs = NULL;
 240
 241         status = resolve_name_all_recv(c, mem_ctx, &addrs, NULL);
 242
 243         if (NT_STATUS_IS_OK(status)) {
 244                 struct tsocket_address *t_addr = socket_address_to_tsocket_address(addrs, addrs[0]);
 245                 if (!t_addr) {
 246                         return NT_STATUS_NO_MEMORY;
 247                 }
 248
 249                 *reply_addr = tsocket_address_inet_addr_string(t_addr, mem_ctx);
 250                 talloc_free(addrs);
 251                 if (!*reply_addr) {
 252                         return NT_STATUS_NO_MEMORY;
 253                 }
 254         }
 255
 256         return status;
 257 }
 258
 259 /*
 260   general name resolution - sync call
 261  */
 262 NTSTATUS resolve_name(struct resolve_context *ctx,
 263                           struct nbt_name *name,
 264                           TALLOC_CTX *mem_ctx,
 265                           const char **reply_addr,
 266                           struct tevent_context *ev)
 267 {
 268         struct composite_context *c = resolve_name_send(ctx, mem_ctx, name, ev);
 269         return resolve_name_recv(c, mem_ctx, reply_addr);
 270 }
 271
 272 /* Initialise a struct nbt_name with a NULL scope */
 273
 274 void make_nbt_name(struct nbt_name *nbt, const char *name, int type)
 275 {
 276         nbt->name = name;
 277         nbt->scope = NULL;
 278         nbt->type = type;
 279 }
 280
 281 /* Initialise a struct nbt_name with a NBT_NAME_CLIENT (0x00) name */
 282
 283 void make_nbt_name_client(struct nbt_name *nbt, const char *name)
 284 {
 285         make_nbt_name(nbt, name, NBT_NAME_CLIENT);
 286 }
 287
 288 /* Initialise a struct nbt_name with a NBT_NAME_SERVER (0x20) name */
 289
 290 void make_nbt_name_server(struct nbt_name *nbt, const char *name)
 291 {
 292         make_nbt_name(nbt, name, NBT_NAME_SERVER);
 293 }
 294
 295