RCSID("$Id$")
#include <freeradius-devel/radiusd.h>
-#include <freeradius-devel/radius_snmp.h>
#include <freeradius-devel/rad_assert.h>
#include <sys/stat.h>
#include <ctype.h>
#include <fcntl.h>
+#ifdef WITH_DYNAMIC_CLIENTS
+#ifdef HAVE_DIRENT_H
+#include <dirent.h>
+#endif
+#endif
+
struct radclient_list {
/*
* FIXME: One set of trees for IPv4, and another for IPv6?
};
-#ifdef WITH_SNMP
-static rbtree_t *tree_num; /* client numbers 0..N */
-static int tree_num_max;
+#ifdef WITH_STATS
+static rbtree_t *tree_num = NULL; /* client numbers 0..N */
+static int tree_num_max = 0;
+#endif
+static RADCLIENT_LIST *root_clients = NULL;
+
+#ifdef WITH_DYNAMIC_CLIENTS
+static fr_fifo_t *deleted_clients = NULL;
#endif
-static RADCLIENT_LIST *root_clients;
/*
* Callback for freeing a client.
*/
void client_free(RADCLIENT *client)
{
+#ifdef WITH_DYNAMIC_CLIENTS
+ if (client->dynamic == 2) {
+ time_t now;
+
+ if (!deleted_clients) {
+ deleted_clients = fr_fifo_create(1024,
+ (void *) client_free);
+ if (!deleted_clients) return; /* MEMLEAK */
+ }
+
+ /*
+ * Mark it as in the fifo, and remember when we
+ * pushed it.
+ */
+ client->dynamic = 3;
+ client->created = now = time(NULL); /* re-set it */
+ fr_fifo_push(deleted_clients, client);
+
+ /*
+ * Peek at the head of the fifo. If it might
+ * still be in use, return. Otherwise, pop it
+ * from the queue and delete it.
+ */
+ client = fr_fifo_peek(deleted_clients);
+ if ((client->created + 120) >= now) return;
+
+ client = fr_fifo_pop(deleted_clients);
+ rad_assert(client != NULL);
+ }
+#endif
+
free(client->longname);
free(client->secret);
free(client->shortname);
free(client->password);
free(client->server);
-#ifdef WITH_SNMP
+#ifdef WITH_STATS
free(client->auth);
#ifdef WITH_ACCOUNTING
free(client->acct);
#endif
#endif
+#ifdef WITH_DYNAMIC_CLIENTS
+ free(client->client_server);
+#endif
+
free(client);
}
-
/*
* Callback for comparing two clients.
*/
{
const RADCLIENT *a = one;
const RADCLIENT *b = two;
+#ifndef WITH_TCP
return fr_ipaddr_cmp(&a->ipaddr, &b->ipaddr);
+#else
+ int rcode;
+
+ rcode = fr_ipaddr_cmp(&a->ipaddr, &b->ipaddr);
+ if (rcode != 0) return rcode;
+
+ /*
+ * Wildcard match
+ */
+ if ((a->proto == IPPROTO_IP) ||
+ (b->proto == IPPROTO_IP)) return 0;
+
+ return (a->proto - b->proto);
+#endif
}
-#ifdef WITH_SNMP
+#ifdef WITH_STATS
static int client_num_cmp(const void *one, const void *two)
{
const RADCLIENT *a = one;
}
if (clients == root_clients) {
-#ifdef WITH_SNMP
+#ifdef WITH_STATS
if (tree_num) rbtree_free(tree_num);
tree_num = NULL;
tree_num_max = 0;
root_clients = NULL;
}
+#ifdef WITH_DYNAMIC_CLIENTS
+ /*
+ * FIXME: No fr_fifo_delete()
+ */
+#endif
+
free(clients);
}
sizeof(client->ipaddr.ipaddr.ip6addr));
} else if (client->prefix < 128) {
- int i;
uint32_t mask, *addr;
addr = (uint32_t *) &client->ipaddr.ipaddr.ip6addr;
- for (i = client->prefix; i < 128; i += 32) {
- mask = ~0;
- mask <<= ((128 - i) & 0x1f);
- addr[i / 32] &= mask;
+ if ((client->prefix & 0x1f) == 0) {
+ mask = 0;
+ } else {
+ mask = ~ ((uint32_t) 0);
+ mask <<= (32 - (client->prefix & 0x1f));
+ mask = htonl(mask);
+ }
+
+ switch (client->prefix >> 5) {
+ case 0:
+ addr[0] &= mask;
+ mask = 0;
+ /* FALL-THROUGH */
+ case 1:
+ addr[1] &= mask;
+ mask = 0;
+ /* FALL-THROUGH */
+ case 2:
+ addr[2] &= mask;
+ mask = 0;
+ /* FALL-THROUGH */
+ case 3:
+ addr[3] &= mask;
+ break;
}
}
break;
*/
int client_add(RADCLIENT_LIST *clients, RADCLIENT *client)
{
+ RADCLIENT *old;
+
if (!client) {
return 0;
}
}
}
+#define namecmp(a) ((!old->a && !client->a) || (old->a && client->a && (strcmp(old->a, client->a) == 0)))
+
/*
* Cannot insert the same client twice.
*/
- if (rbtree_find(clients->trees[client->prefix], client)) {
+ old = rbtree_finddata(clients->trees[client->prefix], client);
+ if (old) {
+ /*
+ * If it's a complete duplicate, then free the new
+ * one, and return "OK".
+ */
+ if ((fr_ipaddr_cmp(&old->ipaddr, &client->ipaddr) == 0) &&
+ (old->prefix == client->prefix) &&
+ namecmp(longname) && namecmp(secret) &&
+ namecmp(shortname) && namecmp(nastype) &&
+ namecmp(login) && namecmp(password) && namecmp(server) &&
+#ifdef WITH_DYNAMIC_CLIENTS
+ (old->lifetime == client->lifetime) &&
+ namecmp(client_server) &&
+#endif
+#ifdef WITH_COA
+ namecmp(coa_name) &&
+ (old->coa_server == client->coa_server) &&
+ (old->coa_pool == client->coa_pool) &&
+#endif
+ (old->message_authenticator == client->message_authenticator)) {
+ DEBUG("WARNING: Ignoring duplicate client %s", client->longname);
+ client_free(client);
+ return 1;
+ }
+
radlog(L_ERR, "Failed to add duplicate client %s",
client->shortname);
return 0;
}
+#undef namecmp
/*
* Other error adding client: likely is fatal.
return 0;
}
-#ifdef WITH_SNMP
+#ifdef WITH_STATS
if (!tree_num) {
tree_num = rbtree_create(client_num_cmp, NULL, 0);
}
}
#endif
+#ifdef WITH_DYNAMIC_CLIENTS
+ /*
+ * More catching of clients added by rlm_sql.
+ *
+ * The sql modules sets the dynamic flag BEFORE calling
+ * us. The client_create() function sets it AFTER
+ * calling us.
+ */
+ if (client->dynamic && (client->lifetime == 0)) {
+ RADCLIENT *network;
+
+ /*
+ * If there IS an enclosing network,
+ * inherit the lifetime from it.
+ */
+ network = client_find(clients, &client->ipaddr, client->proto);
+ if (network) {
+ client->lifetime = network->lifetime;
+ }
+ }
+#endif
+
client->number = tree_num_max;
tree_num_max++;
if (tree_num) rbtree_insert(tree_num, client);
}
+#ifdef WITH_DYNAMIC_CLIENTS
+void client_delete(RADCLIENT_LIST *clients, RADCLIENT *client)
+{
+ if (!client) return;
+
+ if (!clients) clients = root_clients;
+
+ if (!client->dynamic) return;
+
+ rad_assert((client->prefix >= 0) && (client->prefix <= 128));
+
+ client->dynamic = 2; /* signal to client_free */
+
+ rbtree_deletebydata(tree_num, client);
+ rbtree_deletebydata(clients->trees[client->prefix], client);
+}
+#endif
+
+
/*
* Find a client in the RADCLIENTS list by number.
- * This is a support function for the SNMP code.
+ * This is a support function for the statistics code.
*/
RADCLIENT *client_findbynumber(const RADCLIENT_LIST *clients,
int number)
{
-#ifdef WITH_SNMP
+#ifdef WITH_STATS
if (!clients) clients = root_clients;
if (!clients) return NULL;
* Find a client in the RADCLIENTS list.
*/
RADCLIENT *client_find(const RADCLIENT_LIST *clients,
- const fr_ipaddr_t *ipaddr)
+ const fr_ipaddr_t *ipaddr, int proto)
{
int i, max_prefix;
RADCLIENT myclient;
myclient.prefix = i;
myclient.ipaddr = *ipaddr;
+ myclient.proto = proto;
client_sane(&myclient); /* clean up the ipaddress */
if (!clients->trees[i]) continue;
*/
RADCLIENT *client_find_old(const fr_ipaddr_t *ipaddr)
{
- return client_find(root_clients, ipaddr);
+ return client_find(root_clients, ipaddr, IPPROTO_UDP);
}
static struct in_addr cl_ip4addr;
static struct in6_addr cl_ip6addr;
+#ifdef WITH_TCP
+static char *hs_proto = NULL;
+#endif
static const CONF_PARSER client_config[] = {
{ "ipaddr", PW_TYPE_IPADDR,
{ "server", PW_TYPE_STRING_PTR, /* compatability with 2.0-pre */
offsetof(RADCLIENT, server), 0, NULL },
+#ifdef WITH_TCP
+ { "proto", PW_TYPE_STRING_PTR,
+ 0, &hs_proto, NULL },
+ { "max_connections", PW_TYPE_INTEGER,
+ offsetof(RADCLIENT, max_connections), 0, "16" },
+#endif
+
+#ifdef WITH_DYNAMIC_CLIENTS
+ { "dynamic_clients", PW_TYPE_STRING_PTR,
+ offsetof(RADCLIENT, client_server), 0, NULL },
+ { "lifetime", PW_TYPE_INTEGER,
+ offsetof(RADCLIENT, lifetime), 0, NULL },
+ { "rate_limit", PW_TYPE_BOOLEAN,
+ offsetof(RADCLIENT, rate_limit), 0, NULL },
+#endif
+
+#ifdef WITH_COA
+ { "coa_server", PW_TYPE_STRING_PTR,
+ offsetof(RADCLIENT, coa_name), 0, NULL },
+#endif
+
{ NULL, -1, 0, NULL, NULL }
};
memset(c, 0, sizeof(*c));
c->cs = cs;
-#ifdef WITH_SNMP
+#ifdef WITH_STATS
c->auth = rad_malloc(sizeof(*c->auth));
memset(c->auth, 0, sizeof(*c->auth));
c->prefix = -1;
if (cf_section_parse(cs, c, client_config) < 0) {
- client_free(c);
cf_log_err(cf_sectiontoitem(cs),
"Error parsing client section.");
+ error:
+ client_free(c);
+#ifdef WITH_TCP
+ free(hs_proto);
+ hs_proto = NULL;
+#endif
+
return NULL;
}
* per-server clients cannot.
*/
if (in_server && c->server) {
- client_free(c);
cf_log_err(cf_sectiontoitem(cs),
"Clients inside of an server section cannot point to a server.");
- return NULL;
+ goto error;
}
/*
if (prefix_ptr) {
c->prefix = atoi(prefix_ptr + 1);
if ((c->prefix < 0) || (c->prefix > 128)) {
- client_free(c);
cf_log_err(cf_sectiontoitem(cs),
"Invalid Prefix value '%s' for IP.",
prefix_ptr + 1);
- return NULL;
+ goto error;
}
/* Replace '/' with '\0' */
*prefix_ptr = '\0';
* Always get the numeric representation of IP
*/
if (ip_hton(name2, AF_UNSPEC, &c->ipaddr) < 0) {
- client_free(c);
cf_log_err(cf_sectiontoitem(cs),
"Failed to look up hostname %s: %s",
- name2, librad_errstr);
- return NULL;
+ name2, fr_strerror());
+ goto error;
}
if (prefix_ptr) *prefix_ptr = '/';
c->ipaddr.ipaddr.ip4addr = cl_ip4addr;
if ((c->prefix < -1) || (c->prefix > 32)) {
- client_free(c);
cf_log_err(cf_sectiontoitem(cs),
"Netmask must be between 0 and 32");
- return NULL;
+ goto error;
}
} else if (cf_pair_find(cs, "ipv6addr")) {
c->ipaddr.ipaddr.ip6addr = cl_ip6addr;
if ((c->prefix < -1) || (c->prefix > 128)) {
- client_free(c);
cf_log_err(cf_sectiontoitem(cs),
"Netmask must be between 0 and 128");
- return NULL;
+ goto error;
}
} else {
cf_log_err(cf_sectiontoitem(cs),
"No IP address defined for the client");
- client_free(c);
- return NULL;
+ goto error;
}
ip_ntoh(&c->ipaddr, buffer, sizeof(buffer));
* Set the short name to the name2
*/
if (!c->shortname) c->shortname = strdup(name2);
+
+ c->proto = IPPROTO_UDP;
+#ifdef WITH_TCP
+ if (hs_proto) {
+ if (strcmp(hs_proto, "udp") == 0) {
+ free(hs_proto);
+ hs_proto = NULL;
+
+ } else if (strcmp(hs_proto, "tcp") == 0) {
+ free(hs_proto);
+ hs_proto = NULL;
+ c->proto = IPPROTO_TCP;
+
+ } else if (strcmp(hs_proto, "*") == 0) {
+ free(hs_proto);
+ hs_proto = NULL;
+ c->proto = IPPROTO_IP; /* fake for dual */
+
+ } else {
+ cf_log_err(cf_sectiontoitem(cs),
+ "Unknown proto \"%s\".", hs_proto);
+ goto error;
+ }
+ }
+#endif
}
if (c->prefix < 0) switch (c->ipaddr.af) {
break;
}
+#ifdef WITH_DYNAMIC_CLIENTS
+ if (c->client_server) {
+ free(c->secret);
+ c->secret = strdup("testing123");
+
+ if (((c->ipaddr.af == AF_INET) &&
+ (c->prefix == 32)) ||
+ ((c->ipaddr.af == AF_INET6) &&
+ (c->prefix == 128))) {
+ cf_log_err(cf_sectiontoitem(cs),
+ "Dynamic clients MUST be a network, not a single IP address.");
+ goto error;
+ }
+
+ return c;
+ }
+#endif
+
if (!c->secret || !*c->secret) {
#ifdef WITH_DHCP
const char *value = NULL;
if (value && (strcmp(value, "yes") == 0)) return c;
#endif
- client_free(c);
cf_log_err(cf_sectiontoitem(cs),
"secret must be at least 1 character long");
- return NULL;
+ goto error;
}
+#ifdef WITH_COA
+ /*
+ * Point the client to the home server pool, OR to the
+ * home server. This gets around the problem of figuring
+ * out which port to use.
+ */
+ if (c->coa_name) {
+ c->coa_pool = home_pool_byname(c->coa_name, HOME_TYPE_COA);
+ if (!c->coa_pool) {
+ c->coa_server = home_server_byname(c->coa_name,
+ HOME_TYPE_COA);
+ }
+ if (!c->coa_pool && !c->coa_server) {
+ cf_log_err(cf_sectiontoitem(cs), "No such home_server or home_server_pool \"%s\"", c->coa_name);
+ goto error;
+ }
+ }
+#endif
return c;
}
+
/*
* Create the linked list of clients from the new configuration
* type. This way we don't have to change too much in the other
* for migration issues.
*/
+#ifdef WITH_DYNAMIC_CLIENTS
+#ifdef HAVE_DIRENT_H
+ if (c->client_server) {
+ const char *value;
+ CONF_PAIR *cp;
+ DIR *dir;
+ struct dirent *dp;
+ struct stat stat_buf;
+ char buf2[2048];
+
+ /*
+ * Find the directory where individual
+ * client definitions are stored.
+ */
+ cp = cf_pair_find(cs, "directory");
+ if (!cp) goto add_client;
+
+ value = cf_pair_value(cp);
+ if (!value) {
+ cf_log_err(cf_sectiontoitem(cs),
+ "The \"directory\" entry must not be empty");
+ client_free(c);
+ return NULL;
+ }
+
+ DEBUG("including dynamic clients in %s", value);
+
+ dir = opendir(value);
+ if (!dir) {
+ cf_log_err(cf_sectiontoitem(cs), "Error reading directory %s: %s", value, strerror(errno));
+ client_free(c);
+ return NULL;
+ }
+
+ /*
+ * Read the directory, ignoring "." files.
+ */
+ while ((dp = readdir(dir)) != NULL) {
+ const char *p;
+ RADCLIENT *dc;
+
+ if (dp->d_name[0] == '.') continue;
+
+ /*
+ * Check for valid characters
+ */
+ for (p = dp->d_name; *p != '\0'; p++) {
+ if (isalpha((int)*p) ||
+ isdigit((int)*p) ||
+ (*p == ':') ||
+ (*p == '.')) continue;
+ break;
+ }
+ if (*p != '\0') continue;
+
+ snprintf(buf2, sizeof(buf2), "%s/%s",
+ value, dp->d_name);
+
+ if ((stat(buf2, &stat_buf) != 0) ||
+ S_ISDIR(stat_buf.st_mode)) continue;
+
+ dc = client_read(buf2, in_server, TRUE);
+ if (!dc) {
+ cf_log_err(cf_sectiontoitem(cs),
+ "Failed reading client file \"%s\"", buf2);
+ client_free(c);
+ return NULL;
+ }
+
+ /*
+ * Validate, and add to the list.
+ */
+ if (!client_validate(clients, c, dc)) {
+
+ client_free(c);
+ return NULL;
+ }
+ } /* loop over the directory */
+ }
+#endif /* HAVE_DIRENT_H */
+#endif /* WITH_DYNAMIC_CLIENTS */
+
+ add_client:
if (!client_add(clients, c)) {
cf_log_err(cf_sectiontoitem(cs),
"Failed to add client %s",
client_free(c);
return NULL;
}
+
}
/*
return clients;
}
+
+#ifdef WITH_DYNAMIC_CLIENTS
+/*
+ * We overload this structure a lot.
+ */
+static const CONF_PARSER dynamic_config[] = {
+ { "FreeRADIUS-Client-IP-Address", PW_TYPE_IPADDR,
+ offsetof(RADCLIENT, ipaddr), 0, NULL },
+ { "FreeRADIUS-Client-IPv6-Address", PW_TYPE_IPV6ADDR,
+ offsetof(RADCLIENT, ipaddr), 0, NULL },
+
+ { "FreeRADIUS-Client-Require-MA", PW_TYPE_BOOLEAN,
+ offsetof(RADCLIENT, message_authenticator), NULL, NULL },
+
+ { "FreeRADIUS-Client-Secret", PW_TYPE_STRING_PTR,
+ offsetof(RADCLIENT, secret), 0, "" },
+ { "FreeRADIUS-Client-Shortname", PW_TYPE_STRING_PTR,
+ offsetof(RADCLIENT, shortname), 0, "" },
+ { "FreeRADIUS-Client-NAS-Type", PW_TYPE_STRING_PTR,
+ offsetof(RADCLIENT, nastype), 0, NULL },
+ { "FreeRADIUS-Client-Virtual-Server", PW_TYPE_STRING_PTR,
+ offsetof(RADCLIENT, server), 0, NULL },
+
+ { NULL, -1, 0, NULL, NULL }
+};
+
+
+int client_validate(RADCLIENT_LIST *clients, RADCLIENT *master, RADCLIENT *c)
+{
+ char buffer[128];
+
+ /*
+ * No virtual server defined. Inherit the parent's
+ * definition.
+ */
+ if (master->server && !c->server) {
+ c->server = strdup(master->server);
+ }
+
+ /*
+ * If the client network isn't global (not tied to a
+ * virtual server), then ensure that this clients server
+ * is the same as the enclosing networks virtual server.
+ */
+ if (master->server &&
+ (strcmp(master->server, c->server) != 0)) {
+ DEBUG("- Cannot add client %s: Virtual server %s is not the same as the virtual server for the network.",
+ ip_ntoh(&c->ipaddr,
+ buffer, sizeof(buffer)),
+ c->server);
+
+ goto error;
+ }
+
+ if (!client_add(clients, c)) {
+ DEBUG("- Cannot add client %s: Internal error",
+ ip_ntoh(&c->ipaddr,
+ buffer, sizeof(buffer)));
+
+ goto error;
+ }
+
+ /*
+ * Initialize the remaining fields.
+ */
+ c->dynamic = TRUE;
+ c->lifetime = master->lifetime;
+ c->created = time(NULL);
+ c->longname = strdup(c->shortname);
+
+ DEBUG("- Added client %s with shared secret %s",
+ ip_ntoh(&c->ipaddr, buffer, sizeof(buffer)),
+ c->secret);
+
+ return 1;
+
+ error:
+ client_free(c);
+ return 0;
+}
+
+
+RADCLIENT *client_create(RADCLIENT_LIST *clients, REQUEST *request)
+{
+ int i, *pi;
+ char **p;
+ RADCLIENT *c;
+ char buffer[128];
+
+ if (!clients || !request) return NULL;
+
+ c = rad_malloc(sizeof(*c));
+ memset(c, 0, sizeof(*c));
+ c->cs = request->client->cs;
+ c->ipaddr.af = AF_UNSPEC;
+
+ for (i = 0; dynamic_config[i].name != NULL; i++) {
+ DICT_ATTR *da;
+ VALUE_PAIR *vp;
+
+ da = dict_attrbyname(dynamic_config[i].name);
+ if (!da) {
+ DEBUG("- Cannot add client %s: attribute \"%s\"is not in the dictionary",
+ ip_ntoh(&request->packet->src_ipaddr,
+ buffer, sizeof(buffer)),
+ dynamic_config[i].name);
+ error:
+ client_free(c);
+ return NULL;
+ }
+
+ vp = pairfind(request->config_items, da->attr, da->vendor);
+ if (!vp) {
+ /*
+ * Not required. Skip it.
+ */
+ if (!dynamic_config[i].dflt) continue;
+
+ DEBUG("- Cannot add client %s: Required attribute \"%s\" is missing.",
+ ip_ntoh(&request->packet->src_ipaddr,
+ buffer, sizeof(buffer)),
+ dynamic_config[i].name);
+ goto error;
+ }
+
+ switch (dynamic_config[i].type) {
+ case PW_TYPE_IPADDR:
+ c->ipaddr.af = AF_INET;
+ c->ipaddr.ipaddr.ip4addr.s_addr = vp->vp_ipaddr;
+ c->prefix = 32;
+ break;
+
+ case PW_TYPE_IPV6ADDR:
+ c->ipaddr.af = AF_INET6;
+ c->ipaddr.ipaddr.ip6addr = vp->vp_ipv6addr;
+ c->prefix = 128;
+ break;
+
+ case PW_TYPE_STRING_PTR:
+ p = (char **) ((char *) c + dynamic_config[i].offset);
+ if (*p) free(*p);
+ *p = strdup(vp->vp_strvalue);
+ break;
+
+ case PW_TYPE_BOOLEAN:
+ pi = (int *) ((char *) c + dynamic_config[i].offset);
+ *pi = vp->vp_integer;
+ break;
+
+ default:
+ goto error;
+ }
+ }
+
+ if (c->ipaddr.af == AF_UNSPEC) {
+ DEBUG("- Cannot add client %s: No IP address was specified.",
+ ip_ntoh(&request->packet->src_ipaddr,
+ buffer, sizeof(buffer)));
+
+ goto error;
+ }
+
+ if (fr_ipaddr_cmp(&request->packet->src_ipaddr, &c->ipaddr) != 0) {
+ char buf2[128];
+
+ DEBUG("- Cannot add client %s: IP address %s do not match",
+ ip_ntoh(&request->packet->src_ipaddr,
+ buffer, sizeof(buffer)),
+ ip_ntoh(&c->ipaddr,
+ buf2, sizeof(buf2)));
+ goto error;
+ }
+
+ if (!client_validate(clients, request->client, c)) {
+ return NULL;
+ }
+
+ return c;
+}
+
+/*
+ * Read a client definition from the given filename.
+ */
+RADCLIENT *client_read(const char *filename, int in_server, int flag)
+{
+ const char *p;
+ RADCLIENT *c;
+ CONF_SECTION *cs;
+ char buffer[256];
+
+ if (!filename) return NULL;
+
+ cs = cf_file_read(filename);
+ if (!cs) return NULL;
+
+ c = client_parse(cf_section_sub_find(cs, "client"), in_server);
+
+ p = strrchr(filename, FR_DIR_SEP);
+ if (p) {
+ p++;
+ } else {
+ p = filename;
+ }
+
+ if (!flag) return c;
+
+ /*
+ * Additional validations
+ */
+ ip_ntoh(&c->ipaddr, buffer, sizeof(buffer));
+ if (strcmp(p, buffer) != 0) {
+ DEBUG("Invalid client definition in %s: IP address %s does not match name %s", filename, buffer, p);
+ client_free(c);
+ return NULL;
+ }
+
+
+
+ return c;
+}
+#endif