channels/iax2-provision.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 1999 - 2006, Digium, Inc.
   5  *
   6  * Mark Spencer <markster@digium.com>
   7  *
   8  * See http://www.asterisk.org for more information about
   9  * the Asterisk project. Please do not directly contact
  10  * any of the maintainers of this project for assistance;
  11  * the project provides a web site, mailing lists and IRC
  12  * channels for your use.
  13  *
  14  * This program is free software, distributed under the terms of
  15  * the GNU General Public License Version 2. See the LICENSE file
  16  * at the top of the source tree.
  17  */
  18
  19 /*! \file
  20  *
  21  * \brief IAX Provisioning Protocol
  22  *
  23  * \author Mark Spencer <markster@digium.com>
  24  */
  25
  26 #include "asterisk.h"
  27
  28 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  29
  30 #include <unistd.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <stdio.h>
  34 #include <netdb.h>
  35 #include <netinet/in.h>
  36 #include <netinet/in_systm.h>
  37 #include <netinet/ip.h>
  38 #include <sys/socket.h>
  39
  40 #include "asterisk/config.h"
  41 #include "asterisk/logger.h"
  42 #include "asterisk/cli.h"
  43 #include "asterisk/lock.h"
  44 #include "asterisk/frame.h"
  45 #include "asterisk/options.h"
  46 #include "asterisk/md5.h"
  47 #include "asterisk/astdb.h"
  48 #include "asterisk/utils.h"
  49 #include "asterisk/acl.h"
  50 #include "iax2.h"
  51 #include "iax2-provision.h"
  52 #include "iax2-parser.h"
  53
  54 #ifndef IPTOS_MINCOST
  55 #define IPTOS_MINCOST 0x02
  56 #endif
  57
  58 static int provinit = 0;
  59
  60 struct iax_template {
  61         int dead;
  62         char name[80];
  63         char src[80];
  64         struct iax_template *next;
  65         char user[20];
  66         char pass[20];
  67         char lang[10];
  68         unsigned short port;
  69         unsigned int server;
  70         unsigned short serverport;
  71         unsigned int altserver;
  72         unsigned int flags;
  73         unsigned int format;
  74         unsigned int tos;
  75 } *templates;
  76
  77 static struct iax_flag {
  78         char *name;
  79         int value;
  80 } iax_flags[] = {
  81         { "register", PROV_FLAG_REGISTER },
  82         { "secure", PROV_FLAG_SECURE },
  83         { "heartbeat", PROV_FLAG_HEARTBEAT },
  84         { "debug", PROV_FLAG_DEBUG },
  85         { "disablecid", PROV_FLAG_DIS_CALLERID },
  86         { "disablecw", PROV_FLAG_DIS_CALLWAIT },
  87         { "disablecidcw", PROV_FLAG_DIS_CIDCW },
  88         { "disable3way", PROV_FLAG_DIS_THREEWAY },
  89 };
  90
  91 char *iax_provflags2str(char *buf, int buflen, unsigned int flags)
  92 {
  93         int x;
  94
  95         if (!buf || buflen < 1)
  96                 return NULL;
  97
  98         buf[0] = '\0';
  99
 100         for (x = 0; x < sizeof(iax_flags) / sizeof(iax_flags[0]); x++) {
 101                 if (flags & iax_flags[x].value){
 102                         strncat(buf, iax_flags[x].name, buflen - strlen(buf) - 1);
 103                         strncat(buf, ",", buflen - strlen(buf) - 1);
 104                 }
 105         }
 106
 107         if (!ast_strlen_zero(buf))
 108                 buf[strlen(buf) - 1] = '\0';
 109         else
 110                 strncpy(buf, "none", buflen - 1);
 111
 112         return buf;
 113 }
 114
 115 static unsigned int iax_str2flags(const char *buf)
 116 {
 117         int x;
 118         int len;
 119         int found;
 120         unsigned int flags = 0;
 121         char *e;
 122         while(buf && *buf) {
 123                 e = strchr(buf, ',');
 124                 if (e)
 125                         len = e - buf;
 126                 else
 127                         len = 0;
 128                 found = 0;
 129                 for (x=0;x<sizeof(iax_flags) / sizeof(iax_flags[0]); x++) {
 130                         if ((len && !strncasecmp(iax_flags[x].name, buf, len)) ||
 131                             (!len && !strcasecmp(iax_flags[x].name, buf))) {
 132                                 flags |= iax_flags[x].value;
 133                                 break;
 134                         }
 135                 }
 136                 if (e) {
 137                         buf = e + 1;
 138                         while(*buf && (*buf < 33))
 139                                 buf++;
 140                 } else
 141                         break;
 142         }
 143         return flags;
 144 }
 145 AST_MUTEX_DEFINE_STATIC(provlock);
 146
 147 static struct iax_template *iax_template_find(const char *s, int allowdead)
 148 {
 149         struct iax_template *cur;
 150         cur = templates;
 151         while(cur) {
 152                 if (!strcasecmp(s, cur->name)) {
 153                         if (!allowdead && cur->dead)
 154                                 cur = NULL;
 155                         break;
 156                 }
 157                 cur = cur->next;
 158         }
 159         return cur;
 160 }
 161
 162 char *iax_prov_complete_template(const char *line, const char *word, int pos, int state)
 163 {
 164         struct iax_template *c;
 165         int which=0;
 166         char *ret = NULL;
 167         int wordlen = strlen(word);
 168
 169         ast_mutex_lock(&provlock);
 170         for (c = templates; c; c = c->next) {
 171                 if (!strncasecmp(word, c->name, wordlen) && ++which > state) {
 172                         ret = strdup(c->name);
 173                         break;
 174                 }
 175         }
 176         ast_mutex_unlock(&provlock);
 177
 178         return ret;
 179 }
 180
 181 static unsigned int prov_ver_calc(struct iax_ie_data *provdata)
 182 {
 183         struct MD5Context md5;
 184         unsigned int tmp[4];
 185         MD5Init(&md5);
 186         MD5Update(&md5, provdata->buf, provdata->pos);
 187         MD5Final((unsigned char *)tmp, &md5);
 188         return tmp[0] ^ tmp[1] ^ tmp[2] ^ tmp[3];
 189 }
 190
 191 int iax_provision_build(struct iax_ie_data *provdata, unsigned int *signature, const char *template, int force)
 192 {
 193         struct iax_template *cur;
 194         unsigned int sig;
 195         char tmp[40];
 196         memset(provdata, 0, sizeof(*provdata));
 197         ast_mutex_lock(&provlock);
 198         cur = iax_template_find(template, 1);
 199         /* If no match, try searching for '*' */
 200         if (!cur)
 201                 cur = iax_template_find("*", 1);
 202         if (cur) {
 203                 /* found it -- add information elements as appropriate */
 204                 if (force || strlen(cur->user))
 205                         iax_ie_append_str(provdata, PROV_IE_USER, cur->user);
 206                 if (force || strlen(cur->pass))
 207                         iax_ie_append_str(provdata, PROV_IE_PASS, cur->pass);
 208                 if (force || strlen(cur->lang))
 209                         iax_ie_append_str(provdata, PROV_IE_LANG, cur->lang);
 210                 if (force || cur->port)
 211                         iax_ie_append_short(provdata, PROV_IE_PORTNO, cur->port);
 212                 if (force || cur->server)
 213                         iax_ie_append_int(provdata, PROV_IE_SERVERIP, cur->server);
 214                 if (force || cur->serverport)
 215                         iax_ie_append_short(provdata, PROV_IE_SERVERPORT, cur->serverport);
 216                 if (force || cur->altserver)
 217                         iax_ie_append_int(provdata, PROV_IE_ALTSERVER, cur->altserver);
 218                 if (force || cur->flags)
 219                         iax_ie_append_int(provdata, PROV_IE_FLAGS, cur->flags);
 220                 if (force || cur->format)
 221                         iax_ie_append_int(provdata, PROV_IE_FORMAT, cur->format);
 222                 if (force || cur->tos)
 223                         iax_ie_append_byte(provdata, PROV_IE_TOS, cur->tos);
 224
 225                 /* Calculate checksum of message so far */
 226                 sig = prov_ver_calc(provdata);
 227                 if (signature)
 228                         *signature = sig;
 229                 /* Store signature */
 230                 iax_ie_append_int(provdata, PROV_IE_PROVVER, sig);
 231                 /* Cache signature for later verification so we need not recalculate all this */
 232                 snprintf(tmp, sizeof(tmp), "v0x%08x", sig);
 233                 ast_db_put("iax/provisioning/cache", template, tmp);
 234         } else
 235                 ast_db_put("iax/provisioning/cache", template, "u");
 236         ast_mutex_unlock(&provlock);
 237         return cur ? 0 : -1;
 238 }
 239
 240 int iax_provision_version(unsigned int *version, const char *template, int force)
 241 {
 242         char tmp[80] = "";
 243         struct iax_ie_data ied;
 244         int ret=0;
 245         memset(&ied, 0, sizeof(ied));
 246
 247         ast_mutex_lock(&provlock);
 248         ast_db_get("iax/provisioning/cache", template, tmp, sizeof(tmp));
 249         if (sscanf(tmp, "v%x", version) != 1) {
 250                 if (strcmp(tmp, "u")) {
 251                         ret = iax_provision_build(&ied, version, template, force);
 252                         if (ret)
 253                                 ast_log(LOG_DEBUG, "Unable to create provisioning packet for '%s'\n", template);
 254                 } else
 255                         ret = -1;
 256         } else if (option_debug)
 257                 ast_log(LOG_DEBUG, "Retrieved cached version '%s' = '%08x'\n", tmp, *version);
 258         ast_mutex_unlock(&provlock);
 259         return ret;
 260 }
 261
 262 static int iax_template_parse(struct iax_template *cur, struct ast_config *cfg, const char *s, const char *def)
 263 {
 264         struct ast_variable *v;
 265         int foundportno = 0;
 266         int foundserverportno = 0;
 267         int x;
 268         struct in_addr ia;
 269         struct hostent *hp;
 270         struct ast_hostent h;
 271         struct iax_template *src, tmp;
 272         const char *t;
 273         if (def) {
 274                 t = ast_variable_retrieve(cfg, s ,"template");
 275                 src = NULL;
 276                 if (t && strlen(t)) {
 277                         src = iax_template_find(t, 0);
 278                         if (!src)
 279                                 ast_log(LOG_WARNING, "Unable to find base template '%s' for creating '%s'.  Trying '%s'\n", t, s, def);
 280                         else
 281                                 def = t;
 282                 }
 283                 if (!src) {
 284                         src = iax_template_find(def, 0);
 285                         if (!src)
 286                                 ast_log(LOG_WARNING, "Unable to locate default base template '%s' for creating '%s', omitting.\n", def, s);
 287                 }
 288                 if (!src)
 289                         return -1;
 290                 ast_mutex_lock(&provlock);
 291                 /* Backup old data */
 292                 memcpy(&tmp, cur, sizeof(tmp));
 293                 /* Restore from src */
 294                 memcpy(cur, src, sizeof(tmp));
 295                 /* Restore important headers */
 296                 memcpy(cur->name, tmp.name, sizeof(cur->name));
 297                 cur->dead = tmp.dead;
 298                 cur->next = tmp.next;
 299                 ast_mutex_unlock(&provlock);
 300         }
 301         if (def)
 302                 strncpy(cur->src, def, sizeof(cur->src) - 1);
 303         else
 304                 cur->src[0] = '\0';
 305         v = ast_variable_browse(cfg, s);
 306         while(v) {
 307                 if (!strcasecmp(v->name, "port") || !strcasecmp(v->name, "serverport")) {
 308                         if ((sscanf(v->value, "%d", &x) == 1) && (x > 0) && (x < 65535)) {
 309                                 if (!strcasecmp(v->name, "port")) {
 310                                         cur->port = x;
 311                                         foundportno = 1;
 312                                 } else {
 313                                         cur->serverport = x;
 314                                         foundserverportno = 1;
 315                                 }
 316                         } else
 317                                 ast_log(LOG_WARNING, "Ignoring invalid %s '%s' for '%s' at line %d\n", v->name, v->value, s, v->lineno);
 318                 } else if (!strcasecmp(v->name, "server") || !strcasecmp(v->name, "altserver")) {
 319                         hp = ast_gethostbyname(v->value, &h);
 320                         if (hp) {
 321                                 memcpy(&ia, hp->h_addr, sizeof(ia));
 322                                 if (!strcasecmp(v->name, "server"))
 323                                         cur->server = ntohl(ia.s_addr);
 324                                 else
 325                                         cur->altserver = ntohl(ia.s_addr);
 326                         } else
 327                                 ast_log(LOG_WARNING, "Ignoring invalid %s '%s' for '%s' at line %d\n", v->name, v->value, s, v->lineno);
 328                 } else if (!strcasecmp(v->name, "codec")) {
 329                         if ((x = ast_getformatbyname(v->value)) > 0) {
 330                                 cur->format = x;
 331                         } else
 332                                 ast_log(LOG_WARNING, "Ignoring invalid codec '%s' for '%s' at line %d\n", v->value, s, v->lineno);
 333                 } else if (!strcasecmp(v->name, "tos")) {
 334                         if (ast_str2tos(v->value, &cur->tos))
 335                                 ast_log(LOG_WARNING, "Invalid tos value at line %d, see doc/ip-tos.txt for more information.\n", v->lineno);
 336                 } else if (!strcasecmp(v->name, "user")) {
 337                         strncpy(cur->user, v->value, sizeof(cur->user) - 1);
 338                         if (strcmp(cur->user, v->value))
 339                                 ast_log(LOG_WARNING, "Truncating username from '%s' to '%s' for '%s' at line %d\n", v->value, cur->user, s, v->lineno);
 340                 } else if (!strcasecmp(v->name, "pass")) {
 341                         strncpy(cur->pass, v->value, sizeof(cur->pass) - 1);
 342                         if (strcmp(cur->pass, v->value))
 343                                 ast_log(LOG_WARNING, "Truncating password from '%s' to '%s' for '%s' at line %d\n", v->value, cur->pass, s, v->lineno);
 344                 } else if (!strcasecmp(v->name, "language")) {
 345                         strncpy(cur->lang, v->value, sizeof(cur->lang) - 1);
 346                         if (strcmp(cur->lang, v->value))
 347                                 ast_log(LOG_WARNING, "Truncating language from '%s' to '%s' for '%s' at line %d\n", v->value, cur->lang, s, v->lineno);
 348                 } else if (!strcasecmp(v->name, "flags")) {
 349                         cur->flags = iax_str2flags(v->value);
 350                 } else if (!strncasecmp(v->name, "flags", 5) && strchr(v->name, '+')) {
 351                         cur->flags |= iax_str2flags(v->value);
 352                 } else if (!strncasecmp(v->name, "flags", 5) && strchr(v->name, '-')) {
 353                         cur->flags &= ~iax_str2flags(v->value);
 354                 } else if (strcasecmp(v->name, "template")) {
 355                         ast_log(LOG_WARNING, "Unknown keyword '%s' in definition of '%s' at line %d\n", v->name, s, v->lineno);
 356                 }
 357                 v = v->next;
 358         }
 359         if (!foundportno)
 360                 cur->port = IAX_DEFAULT_PORTNO;
 361         if (!foundserverportno)
 362                 cur->serverport = IAX_DEFAULT_PORTNO;
 363         return 0;
 364 }
 365
 366 static int iax_process_template(struct ast_config *cfg, char *s, char *def)
 367 {
 368         /* Find an already existing one if there */
 369         struct iax_template *cur;
 370         int mallocd = 0;
 371         cur = templates;
 372         while(cur) {
 373                 if (!strcasecmp(cur->name, s))
 374                         break;
 375                 cur = cur->next;
 376         }
 377         if (!cur) {
 378                 mallocd = 1;
 379                 cur = malloc(sizeof(struct iax_template));
 380                 if (!cur) {
 381                         ast_log(LOG_WARNING, "Out of memory!\n");
 382                         return -1;
 383                 }
 384                 /* Initialize entry */
 385                 memset(cur, 0, sizeof(*cur));
 386                 strncpy(cur->name, s, sizeof(cur->name) - 1);
 387                 cur->dead = 1;
 388         }
 389         if (!iax_template_parse(cur, cfg, s, def))
 390                 cur->dead = 0;
 391
 392         /* Link if we're mallocd */
 393         if (mallocd) {
 394                 ast_mutex_lock(&provlock);
 395                 cur->next = templates;
 396                 templates = cur;
 397                 ast_mutex_unlock(&provlock);
 398         }
 399         return 0;
 400 }
 401
 402 static char show_provisioning_usage[] =
 403 "Usage: iax list provisioning [template]\n"
 404 "       Lists all known IAX provisioning templates or a\n"
 405 "       specific one if specified.\n";
 406
 407 static const char *ifthere(const char *s)
 408 {
 409         if (strlen(s))
 410                 return s;
 411         else
 412                 return "<unspecified>";
 413 }
 414
 415 static const char *iax_server(unsigned int addr)
 416 {
 417         struct in_addr ia;
 418
 419         if (!addr)
 420                 return "<unspecified>";
 421
 422         ia.s_addr = htonl(addr);
 423
 424         return ast_inet_ntoa(ia);
 425 }
 426
 427
 428 static int iax_show_provisioning(int fd, int argc, char *argv[])
 429 {
 430         struct iax_template *cur;
 431         char server[INET_ADDRSTRLEN];
 432         char alternate[INET_ADDRSTRLEN];
 433         char flags[80]; /* Has to be big enough for 'flags' too */
 434         int found = 0;
 435         if ((argc != 3) && (argc != 4))
 436                 return RESULT_SHOWUSAGE;
 437         ast_mutex_lock(&provlock);
 438         for (cur = templates;cur;cur = cur->next) {
 439                 if ((argc == 3) || (!strcasecmp(argv[3], cur->name)))  {
 440                         if (found)
 441                                 ast_cli(fd, "\n");
 442                         ast_copy_string(server, iax_server(cur->server), sizeof(server));
 443                         ast_copy_string(alternate, iax_server(cur->altserver), sizeof(alternate));
 444                         ast_cli(fd, "== %s ==\n", cur->name);
 445                         ast_cli(fd, "Base Templ:   %s\n", strlen(cur->src) ? cur->src : "<none>");
 446                         ast_cli(fd, "Username:     %s\n", ifthere(cur->user));
 447                         ast_cli(fd, "Secret:       %s\n", ifthere(cur->pass));
 448                         ast_cli(fd, "Language:     %s\n", ifthere(cur->lang));
 449                         ast_cli(fd, "Bind Port:    %d\n", cur->port);
 450                         ast_cli(fd, "Server:       %s\n", server);
 451                         ast_cli(fd, "Server Port:  %d\n", cur->serverport);
 452                         ast_cli(fd, "Alternate:    %s\n", alternate);
 453                         ast_cli(fd, "Flags:        %s\n", iax_provflags2str(flags, sizeof(flags), cur->flags));
 454                         ast_cli(fd, "Format:       %s\n", ast_getformatname(cur->format));
 455                         ast_cli(fd, "TOS:          0x%x\n", cur->tos);
 456                         found++;
 457                 }
 458         }
 459         ast_mutex_unlock(&provlock);
 460         if (!found) {
 461                 if (argc == 3)
 462                         ast_cli(fd, "No provisioning templates found\n");
 463                 else
 464                         ast_cli(fd, "No provisioning template matching '%s' found\n", argv[3]);
 465         }
 466         return RESULT_SUCCESS;
 467 }
 468
 469 static struct ast_cli_entry cli_iax2_provision[] = {
 470         { { "iax2", "show", "provisioning", NULL },
 471         iax_show_provisioning, "Display iax provisioning",
 472         show_provisioning_usage, iax_prov_complete_template, },
 473 };
 474
 475 static int iax_provision_init(void)
 476 {
 477         ast_cli_register_multiple(cli_iax2_provision, sizeof(cli_iax2_provision) / sizeof(struct ast_cli_entry));
 478         provinit = 1;
 479         return 0;
 480 }
 481
 482 int iax_provision_unload(void)
 483 {
 484         provinit = 0;
 485         ast_cli_unregister_multiple(cli_iax2_provision, sizeof(cli_iax2_provision) / sizeof(struct ast_cli_entry));
 486         return 0;
 487 }
 488
 489 int iax_provision_reload(void)
 490 {
 491         struct ast_config *cfg;
 492         struct iax_template *cur, *prev, *next;
 493         char *cat;
 494         int found = 0;
 495         if (!provinit)
 496                 iax_provision_init();
 497         /* Mark all as dead.  No need for locking */
 498         cur = templates;
 499         while(cur) {
 500                 cur->dead = 1;
 501                 cur = cur->next;
 502         }
 503         cfg = ast_config_load("iaxprov.conf");
 504         if (cfg) {
 505                 /* Load as appropriate */
 506                 cat = ast_category_browse(cfg, NULL);
 507                 while(cat) {
 508                         if (strcasecmp(cat, "general")) {
 509                                 iax_process_template(cfg, cat, found ? "default" : NULL);
 510                                 found++;
 511                                 if (option_verbose > 2)
 512                                         ast_verbose(VERBOSE_PREFIX_3 "Loaded provisioning template '%s'\n", cat);
 513                         }
 514                         cat = ast_category_browse(cfg, cat);
 515                 }
 516                 ast_config_destroy(cfg);
 517         } else
 518                 ast_log(LOG_NOTICE, "No IAX provisioning configuration found, IAX provisioning disabled.\n");
 519         ast_mutex_lock(&provlock);
 520         /* Drop dead entries while locked */
 521         prev = NULL;
 522         cur = templates;
 523         while(cur) {
 524                 next = cur->next;
 525                 if (cur->dead) {
 526                         if (prev)
 527                                 prev->next = next;
 528                         else
 529                                 templates = next;
 530                         free(cur);
 531                 } else
 532                         prev = cur;
 533                 cur = next;
 534         }
 535         ast_mutex_unlock(&provlock);
 536         /* Purge cached signature DB entries */
 537         ast_db_deltree("iax/provisioning/cache", NULL);
 538         return 0;
 539
 540 }