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
  32 struct resolve_state {
  33         struct resolve_context *ctx;
  34         struct resolve_method *method;
  35         uint32_t flags;
  36         uint16_t port;
  37         struct nbt_name name;
  38         struct composite_context *creq;
  39         struct socket_address **addrs;
  40         char **names;
  41 };
  42
  43 static struct composite_context *setup_next_method(struct composite_context *c);
  44
  45
  46 struct resolve_context {
  47         struct resolve_method {
  48                 resolve_name_send_fn send_fn;
  49                 resolve_name_recv_fn recv_fn;
  50                 void *privdata;
  51                 struct resolve_method *prev, *next;
  52         } *methods;
  53 };
  54
  55 /**
  56  * Initialize a resolve context
  57  */
  58 struct resolve_context *resolve_context_init(TALLOC_CTX *mem_ctx)
  59 {
  60         return talloc_zero(mem_ctx, struct resolve_context);
  61 }
  62
  63 /**
  64  * Add a resolve method
  65  */
  66 bool resolve_context_add_method(struct resolve_context *ctx, resolve_name_send_fn send_fn,
  67                                 resolve_name_recv_fn recv_fn, void *userdata)
  68 {
  69         struct resolve_method *method = talloc_zero(ctx, struct resolve_method);
  70
  71         if (method == NULL)
  72                 return false;
  73
  74         method->send_fn = send_fn;
  75         method->recv_fn = recv_fn;
  76         method->privdata = userdata;
  77         DLIST_ADD_END(ctx->methods, method, struct resolve_method *);
  78         return true;
  79 }
  80
  81 /**
  82   handle completion of one name resolve method
  83 */
  84 static void resolve_handler(struct composite_context *creq)
  85 {
  86         struct composite_context *c = (struct composite_context *)creq->async.private_data;
  87         struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
  88         const struct resolve_method *method = state->method;
  89
  90         c->status = method->recv_fn(creq, state, &state->addrs, &state->names);
  91
  92         if (!NT_STATUS_IS_OK(c->status)) {
  93                 state->method = state->method->next;
  94                 state->creq = setup_next_method(c);
  95                 if (state->creq != NULL) {
  96                         return;
  97                 }
  98         }
  99
 100         if (!NT_STATUS_IS_OK(c->status)) {
 101                 c->state = COMPOSITE_STATE_ERROR;
 102         } else {
 103                 c->state = COMPOSITE_STATE_DONE;
 104         }
 105         if (c->async.fn) {
 106                 c->async.fn(c);
 107         }
 108 }
 109
 110
 111 static struct composite_context *setup_next_method(struct composite_context *c)
 112 {
 113         struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
 114         struct composite_context *creq = NULL;
 115
 116         do {
 117                 if (state->method) {
 118                         creq = state->method->send_fn(c, c->event_ctx,
 119                                                       state->method->privdata,
 120                                                       state->flags,
 121                                                       state->port,
 122                                                       &state->name);
 123                 }
 124                 if (creq == NULL && state->method) state->method = state->method->next;
 125
 126         } while (!creq && state->method);
 127
 128         if (creq) {
 129                 creq->async.fn = resolve_handler;
 130                 creq->async.private_data = c;
 131         }
 132
 133         return creq;
 134 }
 135
 136 /*
 137   general name resolution - async send
 138  */
 139 struct composite_context *resolve_name_all_send(struct resolve_context *ctx,
 140                                                 TALLOC_CTX *mem_ctx,
 141                                                 uint32_t flags,
 142                                                 uint16_t port,
 143                                                 struct nbt_name *name,
 144                                                 struct tevent_context *event_ctx)
 145 {
 146         struct composite_context *c;
 147         struct resolve_state *state;
 148
 149         if (event_ctx == NULL) {
 150                 return NULL;
 151         }
 152
 153         c = composite_create(mem_ctx, event_ctx);
 154         if (c == NULL) return NULL;
 155
 156         if (composite_nomem(c->event_ctx, c)) return c;
 157
 158         state = talloc(c, struct resolve_state);
 159         if (composite_nomem(state, c)) return c;
 160         c->private_data = state;
 161
 162         state->flags = flags;
 163         state->port = port;
 164
 165         c->status = nbt_name_dup(state, name, &state->name);
 166         if (!composite_is_ok(c)) return c;
 167
 168         state->ctx = talloc_reference(state, ctx);
 169         if (composite_nomem(state->ctx, c)) return c;
 170
 171         if (is_ipaddress(state->name.name) ||
 172             strcasecmp(state->name.name, "localhost") == 0) {
 173                 struct in_addr ip = interpret_addr2(state->name.name);
 174
 175                 state->addrs = talloc_array(state, struct socket_address *, 2);
 176                 if (composite_nomem(state->addrs, c)) return c;
 177                 state->addrs[0] = socket_address_from_strings(state->addrs, "ipv4",
 178                                                               inet_ntoa(ip), 0);
 179                 if (composite_nomem(state->addrs[0], c)) return c;
 180                 state->addrs[1] = NULL;
 181                 state->names = talloc_array(state, char *, 2);
 182                 if (composite_nomem(state->names, c)) return c;
 183                 state->names[0] = talloc_strdup(state->names, state->name.name);
 184                 if (composite_nomem(state->names[0], c)) return c;
 185                 state->names[1] = NULL;
 186                 composite_done(c);
 187                 return c;
 188         }
 189
 190         state->method = ctx->methods;
 191         if (state->method == NULL) {
 192                 composite_error(c, NT_STATUS_BAD_NETWORK_NAME);
 193                 return c;
 194         }
 195         state->creq = setup_next_method(c);
 196         if (composite_nomem(state->creq, c)) return c;
 197
 198         return c;
 199 }
 200
 201 /*
 202   general name resolution method - recv side
 203  */
 204 NTSTATUS resolve_name_all_recv(struct composite_context *c,
 205                                TALLOC_CTX *mem_ctx,
 206                                struct socket_address ***addrs,
 207                                char ***names)
 208 {
 209         NTSTATUS status;
 210
 211         status = composite_wait(c);
 212
 213         if (NT_STATUS_IS_OK(status)) {
 214                 struct resolve_state *state = talloc_get_type(c->private_data, struct resolve_state);
 215                 *addrs = talloc_steal(mem_ctx, state->addrs);
 216                 if (names) {
 217                         *names = talloc_steal(mem_ctx, state->names);
 218                 }
 219         }
 220
 221         talloc_free(c);
 222         return status;
 223 }
 224
 225 struct composite_context *resolve_name_send(struct resolve_context *ctx,
 226                                             TALLOC_CTX *mem_ctx,
 227                                             struct nbt_name *name,
 228                                             struct tevent_context *event_ctx)
 229 {
 230         return resolve_name_all_send(ctx, mem_ctx, 0, 0, name, event_ctx);
 231 }
 232
 233 NTSTATUS resolve_name_recv(struct composite_context *c,
 234                            TALLOC_CTX *mem_ctx,
 235                            const char **reply_addr)
 236 {
 237         NTSTATUS status;
 238         struct socket_address **addrs = NULL;
 239
 240         status = resolve_name_all_recv(c, mem_ctx, &addrs, NULL);
 241
 242         if (NT_STATUS_IS_OK(status)) {
 243                 struct tsocket_address *t_addr = socket_address_to_tsocket_address(addrs, addrs[0]);
 244                 if (!t_addr) {
 245                         return NT_STATUS_NO_MEMORY;
 246                 }
 247
 248                 *reply_addr = tsocket_address_inet_addr_string(t_addr, mem_ctx);
 249                 talloc_free(addrs);
 250                 if (!*reply_addr) {
 251                         return NT_STATUS_NO_MEMORY;
 252                 }
 253         }
 254
 255         return status;
 256 }
 257
 258 /*
 259   general name resolution - sync call
 260  */
 261 NTSTATUS resolve_name(struct resolve_context *ctx,
 262                           struct nbt_name *name,
 263                           TALLOC_CTX *mem_ctx,
 264                           const char **reply_addr,
 265                           struct tevent_context *ev)
 266 {
 267         struct composite_context *c = resolve_name_send(ctx, mem_ctx, name, ev);
 268         return resolve_name_recv(c, mem_ctx, reply_addr);
 269 }
 270
 271 /* Initialise a struct nbt_name with a NULL scope */
 272
 273 void make_nbt_name(struct nbt_name *nbt, const char *name, int type)
 274 {
 275         nbt->name = name;
 276         nbt->scope = NULL;
 277         nbt->type = type;
 278 }
 279
 280 /* Initialise a struct nbt_name with a NBT_NAME_CLIENT (0x00) name */
 281
 282 void make_nbt_name_client(struct nbt_name *nbt, const char *name)
 283 {
 284         make_nbt_name(nbt, name, NBT_NAME_CLIENT);
 285 }
 286
 287 /* Initialise a struct nbt_name with a NBT_NAME_SERVER (0x20) name */
 288
 289 void make_nbt_name_server(struct nbt_name *nbt, const char *name)
 290 {
 291         make_nbt_name(nbt, name, NBT_NAME_SERVER);
 292 }
 293
 294