Mon Oct 8 12:39:03 2012

Asterisk developer's documentation


iax2-provision.c

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00001 /*
00002  * Asterisk -- An open source telephony toolkit.
00003  *
00004  * Copyright (C) 1999 - 2006, Digium, Inc.
00005  *
00006  * Mark Spencer <markster@digium.com>
00007  *
00008  * See http://www.asterisk.org for more information about
00009  * the Asterisk project. Please do not directly contact
00010  * any of the maintainers of this project for assistance;
00011  * the project provides a web site, mailing lists and IRC
00012  * channels for your use.
00013  *
00014  * This program is free software, distributed under the terms of
00015  * the GNU General Public License Version 2. See the LICENSE file
00016  * at the top of the source tree.
00017  */
00018 
00019 /*! \file
00020  * 
00021  * \brief IAX Provisioning Protocol 
00022  *
00023  * \author Mark Spencer <markster@digium.com>
00024  */
00025 
00026 /*** MODULEINFO
00027    <support_level>core</support_level>
00028  ***/
00029 
00030 #include "asterisk.h"
00031 
00032 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 369001 $")
00033 
00034 #include <netdb.h>
00035 #include <netinet/in.h>
00036 #include <netinet/in_systm.h>
00037 #include <netinet/ip.h>
00038 #include <sys/socket.h>
00039 
00040 #include "asterisk/config.h"
00041 #include "asterisk/cli.h"
00042 #include "asterisk/lock.h"
00043 #include "asterisk/frame.h"
00044 #include "asterisk/md5.h"
00045 #include "asterisk/astdb.h"
00046 #include "asterisk/utils.h"
00047 #include "asterisk/acl.h"
00048 #include "iax2.h"
00049 #include "iax2-provision.h"
00050 #include "iax2-parser.h"
00051 
00052 static int provinit = 0;
00053 
00054 struct iax_template {
00055    int dead;
00056    char name[80];
00057    char src[80];
00058    char user[20];
00059    char pass[20];
00060    char lang[10];
00061    unsigned short port;
00062    unsigned int server;
00063    unsigned short serverport;
00064    unsigned int altserver;
00065    unsigned int flags;
00066    unsigned int format;
00067    unsigned int tos;
00068    AST_LIST_ENTRY(iax_template) list;
00069 };
00070 
00071 static AST_LIST_HEAD_NOLOCK_STATIC(templates, iax_template);
00072 
00073 AST_MUTEX_DEFINE_STATIC(provlock);
00074 
00075 static struct iax_flag {
00076    char *name;
00077    int value;
00078 } iax_flags[] = {
00079    { "register", PROV_FLAG_REGISTER },
00080    { "secure", PROV_FLAG_SECURE },
00081    { "heartbeat", PROV_FLAG_HEARTBEAT },
00082    { "debug", PROV_FLAG_DEBUG },
00083    { "disablecid", PROV_FLAG_DIS_CALLERID },
00084    { "disablecw", PROV_FLAG_DIS_CALLWAIT },
00085    { "disablecidcw", PROV_FLAG_DIS_CIDCW },
00086    { "disable3way", PROV_FLAG_DIS_THREEWAY },
00087 };
00088 
00089 char *iax_provflags2str(char *buf, int buflen, unsigned int flags)
00090 {
00091    int x;
00092 
00093    if (!buf || buflen < 1)
00094       return NULL;
00095    
00096    buf[0] = '\0';
00097 
00098    for (x = 0; x < ARRAY_LEN(iax_flags); x++) {
00099       if (flags & iax_flags[x].value){
00100          strncat(buf, iax_flags[x].name, buflen - strlen(buf) - 1);
00101          strncat(buf, ",", buflen - strlen(buf) - 1);
00102       }
00103    }
00104 
00105    if (!ast_strlen_zero(buf)) 
00106       buf[strlen(buf) - 1] = '\0';
00107    else
00108       strncpy(buf, "none", buflen - 1);
00109 
00110    return buf;
00111 }
00112 
00113 static unsigned int iax_str2flags(const char *buf)
00114 {
00115    int x;
00116    int len;
00117    unsigned int flags = 0;
00118    char *e;
00119    while(buf && *buf) {
00120       e = strchr(buf, ',');
00121       if (e)
00122          len = e - buf;
00123       else
00124          len = 0;
00125       for (x = 0; x < ARRAY_LEN(iax_flags); x++) {
00126          if ((len && !strncasecmp(iax_flags[x].name, buf, len)) ||
00127              (!len && !strcasecmp(iax_flags[x].name, buf))) {
00128             flags |= iax_flags[x].value;
00129             break;
00130          }
00131       }
00132       if (e) {
00133          buf = e + 1;
00134          while(*buf && (*buf < 33))
00135             buf++;
00136       } else
00137          break;
00138    }
00139    return flags;
00140 }
00141 
00142 static void iax_template_copy(struct iax_template *dst, struct iax_template *src)
00143 {
00144    if (!dst || !src) {
00145       return;
00146    }
00147 
00148    dst->dead = src->dead;
00149    ast_copy_string(dst->name, src->name, sizeof(dst->name));
00150    ast_copy_string(dst->src, src->src, sizeof(dst->src));
00151    ast_copy_string(dst->user, src->user, sizeof(dst->user));
00152    ast_copy_string(dst->pass, src->pass, sizeof(dst->pass));
00153    ast_copy_string(dst->lang, src->lang, sizeof(dst->lang));
00154    dst->port = src->port;
00155    dst->server = src->server;
00156    dst->altserver = src->altserver;
00157    dst->flags = src->flags;
00158    dst->format = src->format;
00159    dst->tos = src->tos;
00160 }
00161 
00162 static struct iax_template *iax_template_find(const char *s, int allowdead)
00163 {
00164    struct iax_template *cur;
00165 
00166    AST_LIST_TRAVERSE(&templates, cur, list) {
00167       if (!strcasecmp(s, cur->name)) {
00168          if (!allowdead && cur->dead) {
00169             cur = NULL;
00170          }
00171          break;
00172       }
00173    }
00174 
00175    return cur;
00176 }
00177 
00178 char *iax_prov_complete_template(const char *line, const char *word, int pos, int state)
00179 {
00180    struct iax_template *c;
00181    int which=0;
00182    char *ret = NULL;
00183    int wordlen = strlen(word);
00184 
00185    if (pos == 3) {
00186       ast_mutex_lock(&provlock);
00187       AST_LIST_TRAVERSE(&templates, c, list) {
00188          if (!strncasecmp(word, c->name, wordlen) && ++which > state) {
00189             ret = ast_strdup(c->name);
00190             break;
00191          }
00192       }
00193       ast_mutex_unlock(&provlock);
00194    }
00195    return ret;
00196 }
00197 
00198 static unsigned int prov_ver_calc(struct iax_ie_data *provdata)
00199 {
00200    struct MD5Context md5;
00201    unsigned int tmp[4];
00202    MD5Init(&md5);
00203    MD5Update(&md5, provdata->buf, provdata->pos);
00204    MD5Final((unsigned char *)tmp, &md5);
00205    return tmp[0] ^ tmp[1] ^ tmp[2] ^ tmp[3];
00206 }
00207 
00208 int iax_provision_build(struct iax_ie_data *provdata, unsigned int *signature, const char *template, int force)
00209 {
00210    struct iax_template *cur;
00211    unsigned int sig;
00212    char tmp[40];
00213    memset(provdata, 0, sizeof(*provdata));
00214    ast_mutex_lock(&provlock);
00215    cur = iax_template_find(template, 1);
00216    /* If no match, try searching for '*' */
00217    if (!cur)
00218       cur = iax_template_find("*", 1);
00219    if (cur) {
00220       /* found it -- add information elements as appropriate */
00221       if (force || strlen(cur->user))
00222          iax_ie_append_str(provdata, PROV_IE_USER, cur->user);
00223       if (force || strlen(cur->pass))
00224          iax_ie_append_str(provdata, PROV_IE_PASS, cur->pass);
00225       if (force || strlen(cur->lang))
00226          iax_ie_append_str(provdata, PROV_IE_LANG, cur->lang);
00227       if (force || cur->port)
00228          iax_ie_append_short(provdata, PROV_IE_PORTNO, cur->port);
00229       if (force || cur->server)
00230          iax_ie_append_int(provdata, PROV_IE_SERVERIP, cur->server);
00231       if (force || cur->serverport)
00232          iax_ie_append_short(provdata, PROV_IE_SERVERPORT, cur->serverport);
00233       if (force || cur->altserver)
00234          iax_ie_append_int(provdata, PROV_IE_ALTSERVER, cur->altserver);
00235       if (force || cur->flags)
00236          iax_ie_append_int(provdata, PROV_IE_FLAGS, cur->flags);
00237       if (force || cur->format)
00238          iax_ie_append_int(provdata, PROV_IE_FORMAT, cur->format);
00239       if (force || cur->tos)
00240          iax_ie_append_byte(provdata, PROV_IE_TOS, cur->tos);
00241       
00242       /* Calculate checksum of message so far */
00243       sig = prov_ver_calc(provdata);
00244       if (signature)
00245          *signature = sig;
00246       /* Store signature */
00247       iax_ie_append_int(provdata, PROV_IE_PROVVER, sig);
00248       /* Cache signature for later verification so we need not recalculate all this */
00249       snprintf(tmp, sizeof(tmp), "v0x%08x", sig);
00250       ast_db_put("iax/provisioning/cache", template, tmp);
00251    } else
00252       ast_db_put("iax/provisioning/cache", template, "u");
00253    ast_mutex_unlock(&provlock);
00254    return cur ? 0 : -1;
00255 }
00256 
00257 int iax_provision_version(unsigned int *version, const char *template, int force)
00258 {
00259    char tmp[80] = "";
00260    struct iax_ie_data ied;
00261    int ret=0;
00262    memset(&ied, 0, sizeof(ied));
00263 
00264    ast_mutex_lock(&provlock);
00265    if (!(ast_db_get("iax/provisioning/cache", template, tmp, sizeof(tmp)))) {
00266       ast_log(LOG_ERROR, "ast_db_get failed to retrieve iax/provisioning/cache\n");
00267       ast_mutex_unlock(&provlock);
00268       return -1;
00269    }
00270    if (sscanf(tmp, "v%30x", version) != 1) {
00271       if (strcmp(tmp, "u")) {
00272          ret = iax_provision_build(&ied, version, template, force);
00273          if (ret)
00274             ast_debug(1, "Unable to create provisioning packet for '%s'\n", template);
00275       } else
00276          ret = -1;
00277    } else
00278       ast_debug(1, "Retrieved cached version '%s' = '%08x'\n", tmp, *version);
00279    ast_mutex_unlock(&provlock);
00280    return ret;
00281 }
00282 
00283 static int iax_template_parse(struct iax_template *cur, struct ast_config *cfg, const char *s, const char *def)
00284 {
00285    struct ast_variable *v;
00286    int foundportno = 0;
00287    int foundserverportno = 0;
00288    int x;
00289    struct in_addr ia;
00290    struct hostent *hp;
00291    struct ast_hostent h;
00292    struct iax_template *src, tmp;
00293    const char *t;
00294    if (def) {
00295       t = ast_variable_retrieve(cfg, s ,"template");
00296       src = NULL;
00297       if (t && strlen(t)) {
00298          src = iax_template_find(t, 0);
00299          if (!src)
00300             ast_log(LOG_WARNING, "Unable to find base template '%s' for creating '%s'.  Trying '%s'\n", t, s, def);
00301          else
00302             def = t;
00303       } 
00304       if (!src) {
00305          src = iax_template_find(def, 0);
00306          if (!src)
00307             ast_log(LOG_WARNING, "Unable to locate default base template '%s' for creating '%s', omitting.\n", def, s);
00308       }
00309       if (!src)
00310          return -1;
00311       ast_mutex_lock(&provlock);
00312       /* Backup old data */
00313       iax_template_copy(&tmp, cur);
00314       /* Restore from src */
00315       iax_template_copy(cur, src);
00316       /* Restore important headers */
00317       memcpy(cur->name, tmp.name, sizeof(cur->name));
00318       cur->dead = tmp.dead;
00319       ast_mutex_unlock(&provlock);
00320    }
00321    if (def)
00322       strncpy(cur->src, def, sizeof(cur->src) - 1);
00323    else
00324       cur->src[0] = '\0';
00325    v = ast_variable_browse(cfg, s);
00326    while(v) {
00327       if (!strcasecmp(v->name, "port") || !strcasecmp(v->name, "serverport")) {
00328          if ((sscanf(v->value, "%5d", &x) == 1) && (x > 0) && (x < 65535)) {
00329             if (!strcasecmp(v->name, "port")) {
00330                cur->port = x;
00331                foundportno = 1;
00332             } else {
00333                cur->serverport = x;
00334                foundserverportno = 1;
00335             }
00336          } else
00337             ast_log(LOG_WARNING, "Ignoring invalid %s '%s' for '%s' at line %d\n", v->name, v->value, s, v->lineno);
00338       } else if (!strcasecmp(v->name, "server") || !strcasecmp(v->name, "altserver")) {
00339          hp = ast_gethostbyname(v->value, &h);
00340          if (hp) {
00341             memcpy(&ia, hp->h_addr, sizeof(ia));
00342             if (!strcasecmp(v->name, "server"))
00343                cur->server = ntohl(ia.s_addr);
00344             else
00345                cur->altserver = ntohl(ia.s_addr);
00346          } else 
00347             ast_log(LOG_WARNING, "Ignoring invalid %s '%s' for '%s' at line %d\n", v->name, v->value, s, v->lineno);
00348       } else if (!strcasecmp(v->name, "codec")) {
00349          if ((x = ast_getformatbyname(v->value)) > 0) {
00350             cur->format = x;
00351          } else
00352             ast_log(LOG_WARNING, "Ignoring invalid codec '%s' for '%s' at line %d\n", v->value, s, v->lineno);
00353       } else if (!strcasecmp(v->name, "tos")) {
00354          if (ast_str2tos(v->value, &cur->tos))
00355             ast_log(LOG_WARNING, "Invalid tos value at line %d, refer to QoS documentation\n", v->lineno);
00356       } else if (!strcasecmp(v->name, "user")) {
00357          strncpy(cur->user, v->value, sizeof(cur->user) - 1);
00358          if (strcmp(cur->user, v->value))
00359             ast_log(LOG_WARNING, "Truncating username from '%s' to '%s' for '%s' at line %d\n", v->value, cur->user, s, v->lineno);
00360       } else if (!strcasecmp(v->name, "pass")) {
00361          strncpy(cur->pass, v->value, sizeof(cur->pass) - 1);
00362          if (strcmp(cur->pass, v->value))
00363             ast_log(LOG_WARNING, "Truncating password from '%s' to '%s' for '%s' at line %d\n", v->value, cur->pass, s, v->lineno);
00364       } else if (!strcasecmp(v->name, "language")) {
00365          strncpy(cur->lang, v->value, sizeof(cur->lang) - 1);
00366          if (strcmp(cur->lang, v->value))
00367             ast_log(LOG_WARNING, "Truncating language from '%s' to '%s' for '%s' at line %d\n", v->value, cur->lang, s, v->lineno);
00368       } else if (!strcasecmp(v->name, "flags")) {
00369          cur->flags = iax_str2flags(v->value);
00370       } else if (!strncasecmp(v->name, "flags", 5) && strchr(v->name, '+')) {
00371          cur->flags |= iax_str2flags(v->value);
00372       } else if (!strncasecmp(v->name, "flags", 5) && strchr(v->name, '-')) {
00373          cur->flags &= ~iax_str2flags(v->value);
00374       } else if (strcasecmp(v->name, "template")) {
00375          ast_log(LOG_WARNING, "Unknown keyword '%s' in definition of '%s' at line %d\n", v->name, s, v->lineno);
00376       }
00377       v = v->next;
00378    }
00379    if (!foundportno)
00380       cur->port = IAX_DEFAULT_PORTNO;
00381    if (!foundserverportno)
00382       cur->serverport = IAX_DEFAULT_PORTNO;
00383    return 0;
00384 }
00385 
00386 static int iax_process_template(struct ast_config *cfg, char *s, char *def)
00387 {
00388    /* Find an already existing one if there */
00389    struct iax_template *cur;
00390    int mallocd = 0;
00391 
00392    cur = iax_template_find(s, 1 /* allow dead */);
00393    if (!cur) {
00394       mallocd = 1;
00395       cur = ast_calloc(1, sizeof(*cur));
00396       if (!cur) {
00397          ast_log(LOG_WARNING, "Out of memory!\n");
00398          return -1;
00399       }
00400       /* Initialize entry */
00401       strncpy(cur->name, s, sizeof(cur->name) - 1);
00402       cur->dead = 1;
00403    }
00404    if (!iax_template_parse(cur, cfg, s, def))
00405       cur->dead = 0;
00406 
00407    /* Link if we're mallocd */
00408    if (mallocd) {
00409       ast_mutex_lock(&provlock);
00410       AST_LIST_INSERT_HEAD(&templates, cur, list);
00411       ast_mutex_unlock(&provlock);
00412    }
00413    return 0;
00414 }
00415 
00416 static const char *ifthere(const char *s)
00417 {
00418    if (strlen(s))
00419       return s;
00420    else
00421       return "<unspecified>";
00422 }
00423 
00424 static const char *iax_server(unsigned int addr)
00425 {
00426    struct in_addr ia;
00427    
00428    if (!addr)
00429       return "<unspecified>";
00430    
00431    ia.s_addr = htonl(addr);
00432 
00433    return ast_inet_ntoa(ia);
00434 }
00435 
00436 
00437 static char *iax_show_provisioning(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
00438 {
00439    struct iax_template *cur;
00440    char server[INET_ADDRSTRLEN];
00441    char alternate[INET_ADDRSTRLEN];
00442    char flags[80];   /* Has to be big enough for 'flags' too */
00443    int found = 0;
00444 
00445    switch (cmd) {
00446    case CLI_INIT:
00447       e->command = "iax2 show provisioning";
00448       e->usage =
00449          "Usage: iax2 show provisioning [template]\n"
00450          "       Lists all known IAX provisioning templates or a\n"
00451          "       specific one if specified.\n";
00452       return NULL;
00453    case CLI_GENERATE:
00454       return iax_prov_complete_template(a->line, a->word, a->pos, a->n);
00455    }
00456 
00457    if ((a->argc != 3) && (a->argc != 4))
00458       return CLI_SHOWUSAGE;
00459 
00460    ast_mutex_lock(&provlock);
00461    AST_LIST_TRAVERSE(&templates, cur, list) {
00462       if ((a->argc == 3) || (!strcasecmp(a->argv[3], cur->name)))  {
00463          if (found) 
00464             ast_cli(a->fd, "\n");
00465          ast_copy_string(server, iax_server(cur->server), sizeof(server));
00466          ast_copy_string(alternate, iax_server(cur->altserver), sizeof(alternate));
00467          ast_cli(a->fd, "== %s ==\n", cur->name);
00468          ast_cli(a->fd, "Base Templ:   %s\n", strlen(cur->src) ? cur->src : "<none>");
00469          ast_cli(a->fd, "Username:     %s\n", ifthere(cur->user));
00470          ast_cli(a->fd, "Secret:       %s\n", ifthere(cur->pass));
00471          ast_cli(a->fd, "Language:     %s\n", ifthere(cur->lang));
00472          ast_cli(a->fd, "Bind Port:    %d\n", cur->port);
00473          ast_cli(a->fd, "Server:       %s\n", server);
00474          ast_cli(a->fd, "Server Port:  %d\n", cur->serverport);
00475          ast_cli(a->fd, "Alternate:    %s\n", alternate);
00476          ast_cli(a->fd, "Flags:        %s\n", iax_provflags2str(flags, sizeof(flags), cur->flags));
00477          ast_cli(a->fd, "Format:       %s\n", ast_getformatname(cur->format));
00478          ast_cli(a->fd, "TOS:          0x%x\n", cur->tos);
00479          found++;
00480       }
00481    }
00482    ast_mutex_unlock(&provlock);
00483    if (!found) {
00484       if (a->argc == 3)
00485          ast_cli(a->fd, "No provisioning templates found\n");
00486       else
00487          ast_cli(a->fd, "No provisioning template matching '%s' found\n", a->argv[3]);
00488    }
00489    return CLI_SUCCESS;
00490 }
00491 
00492 static struct ast_cli_entry cli_iax2_provision[] = {
00493    AST_CLI_DEFINE(iax_show_provisioning, "Display iax provisioning"),
00494 };
00495 
00496 static int iax_provision_init(void)
00497 {
00498    ast_cli_register_multiple(cli_iax2_provision, sizeof(cli_iax2_provision) / sizeof(struct ast_cli_entry));
00499    provinit = 1;
00500    return 0;
00501 }
00502 
00503 static void iax_provision_free_templates(int dead)
00504 {
00505    struct iax_template *cur;
00506 
00507    /* Drop dead or not (depending on dead) entries while locked */
00508    ast_mutex_lock(&provlock);
00509    AST_LIST_TRAVERSE_SAFE_BEGIN(&templates, cur, list) {
00510       if ((dead && cur->dead) || !dead) {
00511          AST_LIST_REMOVE_CURRENT(list);
00512          ast_free(cur);
00513       }
00514    }
00515    AST_LIST_TRAVERSE_SAFE_END;
00516    ast_mutex_unlock(&provlock);
00517 }
00518 
00519 int iax_provision_unload(void)
00520 {
00521    provinit = 0;
00522    ast_cli_unregister_multiple(cli_iax2_provision, sizeof(cli_iax2_provision) / sizeof(struct ast_cli_entry));
00523    iax_provision_free_templates(0 /* Remove all templates. */);
00524 
00525    return 0;
00526 }
00527 
00528 int iax_provision_reload(int reload)
00529 {
00530    struct ast_config *cfg;
00531    struct iax_template *cur;
00532    char *cat;
00533    int found = 0;
00534    struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
00535    if (!provinit)
00536       iax_provision_init();
00537    
00538    cfg = ast_config_load2("iaxprov.conf", "chan_iax2", config_flags);
00539    if (cfg != NULL && cfg != CONFIG_STATUS_FILEUNCHANGED && cfg != CONFIG_STATUS_FILEINVALID) {
00540       /* Mark all as dead.  No need for locking */
00541       AST_LIST_TRAVERSE(&templates, cur, list) {
00542          cur->dead = 1;
00543       }
00544 
00545       /* Load as appropriate */
00546       cat = ast_category_browse(cfg, NULL);
00547       while(cat) {
00548          if (strcasecmp(cat, "general")) {
00549             iax_process_template(cfg, cat, found ? "default" : NULL);
00550             found++;
00551             ast_verb(3, "Loaded provisioning template '%s'\n", cat);
00552          }
00553          cat = ast_category_browse(cfg, cat);
00554       }
00555       ast_config_destroy(cfg);
00556    } else if (cfg == CONFIG_STATUS_FILEUNCHANGED)
00557       return 0;
00558    else
00559       ast_log(LOG_NOTICE, "No IAX provisioning configuration found, IAX provisioning disabled.\n");
00560 
00561    iax_provision_free_templates(1 /* remove only marked as dead */);
00562 
00563    /* Purge cached signature DB entries */
00564    ast_db_deltree("iax/provisioning/cache", NULL);
00565    return 0;
00566 }

Generated on Mon Oct 8 12:39:03 2012 for Asterisk - The Open Source Telephony Project by  doxygen 1.4.7