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, /* RESOLVE_NAME_FLAG_* */
 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                 state->addrs = talloc_array(state, struct socket_address *, 2);
 175                 if (composite_nomem(state->addrs, c)) return c;
 176                 state->addrs[0] = socket_address_from_strings(state->addrs, "ip",
 177                                                               state->name.name, 0);
 178                 if (composite_nomem(state->addrs[0], c)) return c;
 179                 state->addrs[1] = NULL;
 180                 state->names = talloc_array(state, char *, 2);
 181                 if (composite_nomem(state->names, c)) return c;
 182                 state->names[0] = talloc_strdup(state->names, state->name.name);
 183                 if (composite_nomem(state->names[0], c)) return c;
 184                 state->names[1] = NULL;
 185                 composite_done(c);
 186                 return c;
 187         }
 188
 189         state->method = ctx->methods;
 190         if (state->method == NULL) {
 191                 composite_error(c, NT_STATUS_BAD_NETWORK_NAME);
 192                 return c;
 193         }
 194         state->creq = setup_next_method(c);
 195         if (composite_nomem(state->creq, c)) return c;
 196
 197         return c;
 198 }
 199
 200 /*
 201   general name resolution method - recv side
 202  */
 203 NTSTATUS resolve_name_all_recv(struct composite_context *c,
 204                                TALLOC_CTX *mem_ctx,
 205                                struct socket_address ***addrs,
 206                                char ***names)
 207 {
 208         NTSTATUS status;
 209
 210         status = composite_wait(c);
 211
 212         if (NT_STATUS_IS_OK(status)) {
 213                 struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
 214                 *addrs = talloc_steal(mem_ctx, state->addrs);
 215                 if (names) {
 216                         *names = talloc_steal(mem_ctx, state->names);
 217                 }
 218         }
 219
 220         talloc_free(c);
 221         return status;
 222 }
 223
 224 struct composite_context *resolve_name_ex_send(struct resolve_context *ctx,
 225                                                TALLOC_CTX *mem_ctx,
 226                                                uint32_t flags, /* RESOLVE_NAME_FLAG_* */
 227                                                uint16_t port,
 228                                                struct nbt_name *name,
 229                                                struct tevent_context *event_ctx)
 230 {
 231         return resolve_name_all_send(ctx, mem_ctx, flags, port, name, event_ctx);
 232 }
 233
 234 struct composite_context *resolve_name_send(struct resolve_context *ctx,
 235                                             TALLOC_CTX *mem_ctx,
 236                                             struct nbt_name *name,
 237                                             struct tevent_context *event_ctx)
 238 {
 239         return resolve_name_ex_send(ctx, mem_ctx, 0, 0, name, event_ctx);
 240 }
 241
 242 NTSTATUS resolve_name_recv(struct composite_context *c,
 243                            TALLOC_CTX *mem_ctx,
 244                            const char **reply_addr)
 245 {
 246         NTSTATUS status;
 247         struct socket_address **addrs = NULL;
 248
 249         status = resolve_name_all_recv(c, mem_ctx, &addrs, NULL);
 250
 251         if (NT_STATUS_IS_OK(status)) {
 252                 struct tsocket_address *t_addr = socket_address_to_tsocket_address(addrs, addrs[0]);
 253                 if (!t_addr) {
 254                         return NT_STATUS_NO_MEMORY;
 255                 }
 256
 257                 *reply_addr = tsocket_address_inet_addr_string(t_addr, mem_ctx);
 258                 talloc_free(addrs);
 259                 if (!*reply_addr) {
 260                         return NT_STATUS_NO_MEMORY;
 261                 }
 262         }
 263
 264         return status;
 265 }
 266
 267 /*
 268   receive multiple responses from resolve_name_send()
 269  */
 270 NTSTATUS resolve_name_multiple_recv(struct composite_context *c,
 271                                     TALLOC_CTX *mem_ctx,
 272                                     const char ***reply_addrs)
 273 {
 274         NTSTATUS status;
 275         struct socket_address **addrs = NULL;
 276         int i;
 277
 278         status = resolve_name_all_recv(c, mem_ctx, &addrs, NULL);
 279         NT_STATUS_NOT_OK_RETURN(status);
 280
 281         /* count the addresses */
 282         for (i=0; addrs[i]; i++) ;
 283
 284         *reply_addrs = talloc_array(mem_ctx, const char *, i+1);
 285         NT_STATUS_HAVE_NO_MEMORY(*reply_addrs);
 286
 287         for (i=0; addrs[i]; i++) {
 288                 struct tsocket_address *t_addr = socket_address_to_tsocket_address(addrs, addrs[i]);
 289                 NT_STATUS_HAVE_NO_MEMORY(t_addr);
 290
 291                 (*reply_addrs)[i] = tsocket_address_inet_addr_string(t_addr, *reply_addrs);
 292                 NT_STATUS_HAVE_NO_MEMORY((*reply_addrs)[i]);
 293         }
 294         (*reply_addrs)[i] = NULL;
 295
 296         talloc_free(addrs);
 297
 298         return status;
 299 }
 300
 301 /*
 302   general name resolution - sync call
 303  */
 304 NTSTATUS resolve_name_ex(struct resolve_context *ctx,
 305                          uint32_t flags, /* RESOLVE_NAME_FLAG_* */
 306                          uint16_t port,
 307                          struct nbt_name *name,
 308                          TALLOC_CTX *mem_ctx,
 309                          const char **reply_addr,
 310                          struct tevent_context *ev)
 311 {
 312         struct composite_context *c = resolve_name_ex_send(ctx, mem_ctx, flags, port, name, ev);
 313         return resolve_name_recv(c, mem_ctx, reply_addr);
 314 }
 315
 316
 317 /* Initialise a struct nbt_name with a NULL scope */
 318
 319 void make_nbt_name(struct nbt_name *nbt, const char *name, int type)
 320 {
 321         nbt->name = name;
 322         nbt->scope = NULL;
 323         nbt->type = type;
 324 }
 325
 326 /* Initialise a struct nbt_name with a NBT_NAME_CLIENT (0x00) name */
 327
 328 void make_nbt_name_client(struct nbt_name *nbt, const char *name)
 329 {
 330         make_nbt_name(nbt, name, NBT_NAME_CLIENT);
 331 }
 332
 333 /* Initialise a struct nbt_name with a NBT_NAME_SERVER (0x20) name */
 334
 335 void make_nbt_name_server(struct nbt_name *nbt, const char *name)
 336 {
 337         make_nbt_name(nbt, name, NBT_NAME_SERVER);
 338 }
 339
 340