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 #undef strcasecmp
  34
  35 struct resolve_state {
  36         struct resolve_context *ctx;
  37         struct resolve_method *method;
  38         uint32_t flags;
  39         uint16_t port;
  40         struct nbt_name name;
  41         struct composite_context *creq;
  42         struct socket_address **addrs;
  43         char **names;
  44 };
  45
  46 static struct composite_context *setup_next_method(struct composite_context *c);
  47
  48
  49 struct resolve_context {
  50         struct resolve_method {
  51                 resolve_name_send_fn send_fn;
  52                 resolve_name_recv_fn recv_fn;
  53                 void *privdata;
  54                 struct resolve_method *prev, *next;
  55         } *methods;
  56 };
  57
  58 /**
  59  * Initialize a resolve context
  60  */
  61 struct resolve_context *resolve_context_init(TALLOC_CTX *mem_ctx)
  62 {
  63         return talloc_zero(mem_ctx, struct resolve_context);
  64 }
  65
  66 /**
  67  * Add a resolve method
  68  */
  69 bool resolve_context_add_method(struct resolve_context *ctx, resolve_name_send_fn send_fn,
  70                                 resolve_name_recv_fn recv_fn, void *userdata)
  71 {
  72         struct resolve_method *method = talloc_zero(ctx, struct resolve_method);
  73
  74         if (method == NULL)
  75                 return false;
  76
  77         method->send_fn = send_fn;
  78         method->recv_fn = recv_fn;
  79         method->privdata = userdata;
  80         DLIST_ADD_END(ctx->methods, method);
  81         return true;
  82 }
  83
  84 /**
  85   handle completion of one name resolve method
  86 */
  87 static void resolve_handler(struct composite_context *creq)
  88 {
  89         struct composite_context *c = (struct composite_context *)creq->async.private_data;
  90         struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
  91         const struct resolve_method *method = state->method;
  92
  93         c->status = method->recv_fn(creq, state, &state->addrs, &state->names);
  94
  95         if (!NT_STATUS_IS_OK(c->status)) {
  96                 state->method = state->method->next;
  97                 state->creq = setup_next_method(c);
  98                 if (state->creq != NULL) {
  99                         return;
 100                 }
 101         }
 102
 103         if (!NT_STATUS_IS_OK(c->status)) {
 104                 c->state = COMPOSITE_STATE_ERROR;
 105         } else {
 106                 c->state = COMPOSITE_STATE_DONE;
 107         }
 108         if (c->async.fn) {
 109                 c->async.fn(c);
 110         }
 111 }
 112
 113
 114 static struct composite_context *setup_next_method(struct composite_context *c)
 115 {
 116         struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
 117         struct composite_context *creq = NULL;
 118
 119         do {
 120                 if (state->method) {
 121                         creq = state->method->send_fn(c, c->event_ctx,
 122                                                       state->method->privdata,
 123                                                       state->flags,
 124                                                       state->port,
 125                                                       &state->name);
 126                 }
 127                 if (creq == NULL && state->method) state->method = state->method->next;
 128
 129         } while (!creq && state->method);
 130
 131         if (creq) {
 132                 creq->async.fn = resolve_handler;
 133                 creq->async.private_data = c;
 134         }
 135
 136         return creq;
 137 }
 138
 139 /*
 140   general name resolution - async send
 141  */
 142 struct composite_context *resolve_name_all_send(struct resolve_context *ctx,
 143                                                 TALLOC_CTX *mem_ctx,
 144                                                 uint32_t flags, /* RESOLVE_NAME_FLAG_* */
 145                                                 uint16_t port,
 146                                                 struct nbt_name *name,
 147                                                 struct tevent_context *event_ctx)
 148 {
 149         struct composite_context *c;
 150         struct resolve_state *state;
 151
 152         if (event_ctx == NULL) {
 153                 return NULL;
 154         }
 155
 156         c = composite_create(mem_ctx, event_ctx);
 157         if (c == NULL) return NULL;
 158
 159         if (composite_nomem(c->event_ctx, c)) return c;
 160
 161         state = talloc(c, struct resolve_state);
 162         if (composite_nomem(state, c)) return c;
 163         c->private_data = state;
 164
 165         state->flags = flags;
 166         state->port = port;
 167
 168         c->status = nbt_name_dup(state, name, &state->name);
 169         if (!composite_is_ok(c)) return c;
 170
 171         state->ctx = talloc_reference(state, ctx);
 172         if (composite_nomem(state->ctx, c)) return c;
 173
 174         if (is_ipaddress(state->name.name) ||
 175             strcasecmp(state->name.name, "localhost") == 0) {
 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, "ip",
 179                                                               state->name.name, 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_ex_send(struct resolve_context *ctx,
 227                                                TALLOC_CTX *mem_ctx,
 228                                                uint32_t flags, /* RESOLVE_NAME_FLAG_* */
 229                                                uint16_t port,
 230                                                struct nbt_name *name,
 231                                                struct tevent_context *event_ctx)
 232 {
 233         return resolve_name_all_send(ctx, mem_ctx, flags, port, name, event_ctx);
 234 }
 235
 236 struct composite_context *resolve_name_send(struct resolve_context *ctx,
 237                                             TALLOC_CTX *mem_ctx,
 238                                             struct nbt_name *name,
 239                                             struct tevent_context *event_ctx)
 240 {
 241         return resolve_name_ex_send(ctx, mem_ctx, 0, 0, name, event_ctx);
 242 }
 243
 244 NTSTATUS resolve_name_recv(struct composite_context *c,
 245                            TALLOC_CTX *mem_ctx,
 246                            const char **reply_addr)
 247 {
 248         NTSTATUS status;
 249         struct socket_address **addrs = NULL;
 250
 251         status = resolve_name_all_recv(c, mem_ctx, &addrs, NULL);
 252
 253         if (NT_STATUS_IS_OK(status)) {
 254                 struct tsocket_address *t_addr = socket_address_to_tsocket_address(addrs, addrs[0]);
 255                 if (!t_addr) {
 256                         return NT_STATUS_NO_MEMORY;
 257                 }
 258
 259                 *reply_addr = tsocket_address_inet_addr_string(t_addr, mem_ctx);
 260                 talloc_free(addrs);
 261                 if (!*reply_addr) {
 262                         return NT_STATUS_NO_MEMORY;
 263                 }
 264         }
 265
 266         return status;
 267 }
 268
 269 /*
 270   receive multiple responses from resolve_name_send()
 271  */
 272 NTSTATUS resolve_name_multiple_recv(struct composite_context *c,
 273                                     TALLOC_CTX *mem_ctx,
 274                                     const char ***reply_addrs)
 275 {
 276         NTSTATUS status;
 277         struct socket_address **addrs = NULL;
 278         int i;
 279
 280         status = resolve_name_all_recv(c, mem_ctx, &addrs, NULL);
 281         NT_STATUS_NOT_OK_RETURN(status);
 282
 283         /* count the addresses */
 284         for (i=0; addrs[i]; i++) ;
 285
 286         *reply_addrs = talloc_array(mem_ctx, const char *, i+1);
 287         NT_STATUS_HAVE_NO_MEMORY(*reply_addrs);
 288
 289         for (i=0; addrs[i]; i++) {
 290                 struct tsocket_address *t_addr = socket_address_to_tsocket_address(addrs, addrs[i]);
 291                 NT_STATUS_HAVE_NO_MEMORY(t_addr);
 292
 293                 (*reply_addrs)[i] = tsocket_address_inet_addr_string(t_addr, *reply_addrs);
 294                 NT_STATUS_HAVE_NO_MEMORY((*reply_addrs)[i]);
 295         }
 296         (*reply_addrs)[i] = NULL;
 297
 298         talloc_free(addrs);
 299
 300         return status;
 301 }
 302
 303 /*
 304   general name resolution - sync call
 305  */
 306 NTSTATUS resolve_name_ex(struct resolve_context *ctx,
 307                          uint32_t flags, /* RESOLVE_NAME_FLAG_* */
 308                          uint16_t port,
 309                          struct nbt_name *name,
 310                          TALLOC_CTX *mem_ctx,
 311                          const char **reply_addr,
 312                          struct tevent_context *ev)
 313 {
 314         struct composite_context *c = resolve_name_ex_send(ctx, mem_ctx, flags, port, name, ev);
 315         return resolve_name_recv(c, mem_ctx, reply_addr);
 316 }
 317
 318
 319 /* Initialise a struct nbt_name with a NULL scope */
 320
 321 void make_nbt_name(struct nbt_name *nbt, const char *name, int type)
 322 {
 323         nbt->name = name;
 324         nbt->scope = NULL;
 325         nbt->type = type;
 326 }
 327
 328 /* Initialise a struct nbt_name with a NBT_NAME_CLIENT (0x00) name */
 329
 330 void make_nbt_name_client(struct nbt_name *nbt, const char *name)
 331 {
 332         make_nbt_name(nbt, name, NBT_NAME_CLIENT);
 333 }
 334
 335 /* Initialise a struct nbt_name with a NBT_NAME_SERVER (0x20) name */
 336
 337 void make_nbt_name_server(struct nbt_name *nbt, const char *name)
 338 {
 339         make_nbt_name(nbt, name, NBT_NAME_SERVER);
 340 }
 341
 342