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authorRene Mayrhofer <rene@mayrhofer.eu.org>2006-05-22 05:12:18 +0000
committerRene Mayrhofer <rene@mayrhofer.eu.org>2006-05-22 05:12:18 +0000
commitaa0f5b38aec14428b4b80e06f90ff781f8bca5f1 (patch)
tree95f3d0c8cb0d59d88900dbbd72110d7ab6e15b2a /lib/liblwres/getaddrinfo.c
parent7c383bc22113b23718be89fe18eeb251942d7356 (diff)
downloadvyos-strongswan-aa0f5b38aec14428b4b80e06f90ff781f8bca5f1.tar.gz
vyos-strongswan-aa0f5b38aec14428b4b80e06f90ff781f8bca5f1.zip
Import initial strongswan 2.7.0 version into SVN.
Diffstat (limited to 'lib/liblwres/getaddrinfo.c')
-rw-r--r--lib/liblwres/getaddrinfo.c692
1 files changed, 692 insertions, 0 deletions
diff --git a/lib/liblwres/getaddrinfo.c b/lib/liblwres/getaddrinfo.c
new file mode 100644
index 000000000..06cb39ffc
--- /dev/null
+++ b/lib/liblwres/getaddrinfo.c
@@ -0,0 +1,692 @@
+/*
+ * Copyright (C) 1999-2001 Internet Software Consortium.
+ *
+ * This code is derived from software contributed to Internet Software
+ * Consortium by Berkeley Software Design, Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM AND
+ * BERKELEY SOFTWARE DESIGN, INC DISCLAIM ALL WARRANTIES WITH REGARD TO
+ * THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE CONSORTIUM OR BERKELEY
+ * SOFTWARE DESIGN, INC BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
+ * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: getaddrinfo.c,v 1.1 2004/03/15 20:35:25 as Exp $ */
+
+#include <config.h>
+
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include <lwres/lwres.h>
+#include <lwres/net.h>
+#include <lwres/netdb.h>
+
+#define SA(addr) ((struct sockaddr *)(addr))
+#define SIN(addr) ((struct sockaddr_in *)(addr))
+#define SIN6(addr) ((struct sockaddr_in6 *)(addr))
+#define SUN(addr) ((struct sockaddr_un *)(addr))
+
+static struct addrinfo
+ *ai_reverse(struct addrinfo *oai),
+ *ai_clone(struct addrinfo *oai, int family),
+ *ai_alloc(int family, int addrlen);
+#ifdef AF_LOCAL
+static int get_local(const char *name, int socktype, struct addrinfo **res);
+#endif
+
+static int add_ipv4(const char *hostname, int flags, struct addrinfo **aip,
+ int socktype, int port);
+static int add_ipv6(const char *hostname, int flags, struct addrinfo **aip,
+ int socktype, int port);
+static void set_order(int, int (**)(const char *, int, struct addrinfo **,
+ int, int));
+
+#define FOUND_IPV4 0x1
+#define FOUND_IPV6 0x2
+#define FOUND_MAX 2
+
+#define ISC_AI_MASK (AI_PASSIVE|AI_CANONNAME|AI_NUMERICHOST)
+
+int
+lwres_getaddrinfo(const char *hostname, const char *servname,
+ const struct addrinfo *hints, struct addrinfo **res)
+{
+ struct servent *sp;
+ const char *proto;
+ int family, socktype, flags, protocol;
+ struct addrinfo *ai, *ai_list;
+ int port, err, i;
+ int (*net_order[FOUND_MAX+1])(const char *, int, struct addrinfo **,
+ int, int);
+
+ if (hostname == NULL && servname == NULL)
+ return (EAI_NONAME);
+
+ proto = NULL;
+ if (hints != NULL) {
+ if ((hints->ai_flags & ~(ISC_AI_MASK)) != 0)
+ return (EAI_BADFLAGS);
+ if (hints->ai_addrlen || hints->ai_canonname ||
+ hints->ai_addr || hints->ai_next) {
+ errno = EINVAL;
+ return (EAI_SYSTEM);
+ }
+ family = hints->ai_family;
+ socktype = hints->ai_socktype;
+ protocol = hints->ai_protocol;
+ flags = hints->ai_flags;
+ switch (family) {
+ case AF_UNSPEC:
+ switch (hints->ai_socktype) {
+ case SOCK_STREAM:
+ proto = "tcp";
+ break;
+ case SOCK_DGRAM:
+ proto = "udp";
+ break;
+ }
+ break;
+ case AF_INET:
+ case AF_INET6:
+ switch (hints->ai_socktype) {
+ case 0:
+ break;
+ case SOCK_STREAM:
+ proto = "tcp";
+ break;
+ case SOCK_DGRAM:
+ proto = "udp";
+ break;
+ case SOCK_RAW:
+ break;
+ default:
+ return (EAI_SOCKTYPE);
+ }
+ break;
+#ifdef AF_LOCAL
+ case AF_LOCAL:
+ switch (hints->ai_socktype) {
+ case 0:
+ break;
+ case SOCK_STREAM:
+ break;
+ case SOCK_DGRAM:
+ break;
+ default:
+ return (EAI_SOCKTYPE);
+ }
+ break;
+#endif
+ default:
+ return (EAI_FAMILY);
+ }
+ } else {
+ protocol = 0;
+ family = 0;
+ socktype = 0;
+ flags = 0;
+ }
+
+#ifdef AF_LOCAL
+ /*
+ * First, deal with AF_LOCAL. If the family was not set,
+ * then assume AF_LOCAL if the first character of the
+ * hostname/servname is '/'.
+ */
+
+ if (hostname != NULL &&
+ (family == AF_LOCAL || (family == 0 && *hostname == '/')))
+ return (get_local(hostname, socktype, res));
+
+ if (servname != NULL &&
+ (family == AF_LOCAL || (family == 0 && *servname == '/')))
+ return (get_local(servname, socktype, res));
+#endif
+
+ /*
+ * Ok, only AF_INET and AF_INET6 left.
+ */
+ ai_list = NULL;
+
+ /*
+ * First, look up the service name (port) if it was
+ * requested. If the socket type wasn't specified, then
+ * try and figure it out.
+ */
+ if (servname != NULL) {
+ char *e;
+
+ port = strtol(servname, &e, 10);
+ if (*e == '\0') {
+ if (socktype == 0)
+ return (EAI_SOCKTYPE);
+ if (port < 0 || port > 65535)
+ return (EAI_SERVICE);
+ port = htons((unsigned short) port);
+ } else {
+ sp = getservbyname(servname, proto);
+ if (sp == NULL)
+ return (EAI_SERVICE);
+ port = sp->s_port;
+ if (socktype == 0) {
+ if (strcmp(sp->s_proto, "tcp") == 0)
+ socktype = SOCK_STREAM;
+ else if (strcmp(sp->s_proto, "udp") == 0)
+ socktype = SOCK_DGRAM;
+ }
+ }
+ } else
+ port = 0;
+
+ /*
+ * Next, deal with just a service name, and no hostname.
+ * (we verified that one of them was non-null up above).
+ */
+ if (hostname == NULL && (flags & AI_PASSIVE) != 0) {
+ if (family == AF_INET || family == 0) {
+ ai = ai_alloc(AF_INET, sizeof(struct sockaddr_in));
+ if (ai == NULL)
+ return (EAI_MEMORY);
+ ai->ai_socktype = socktype;
+ ai->ai_protocol = protocol;
+ SIN(ai->ai_addr)->sin_port = port;
+ ai->ai_next = ai_list;
+ ai_list = ai;
+ }
+
+ if (family == AF_INET6 || family == 0) {
+ ai = ai_alloc(AF_INET6, sizeof(struct sockaddr_in6));
+ if (ai == NULL) {
+ lwres_freeaddrinfo(ai_list);
+ return (EAI_MEMORY);
+ }
+ ai->ai_socktype = socktype;
+ ai->ai_protocol = protocol;
+ SIN6(ai->ai_addr)->sin6_port = port;
+ ai->ai_next = ai_list;
+ ai_list = ai;
+ }
+
+ *res = ai_list;
+ return (0);
+ }
+
+ /*
+ * If the family isn't specified or AI_NUMERICHOST specified,
+ * check first to see if it is a numeric address.
+ * Though the gethostbyname2() routine
+ * will recognize numeric addresses, it will only recognize
+ * the format that it is being called for. Thus, a numeric
+ * AF_INET address will be treated by the AF_INET6 call as
+ * a domain name, and vice versa. Checking for both numerics
+ * here avoids that.
+ */
+ if (hostname != NULL &&
+ (family == 0 || (flags & AI_NUMERICHOST) != 0)) {
+ char abuf[sizeof(struct in6_addr)];
+ char nbuf[NI_MAXHOST];
+ int addrsize, addroff;
+#ifdef LWRES_HAVE_SIN6_SCOPE_ID
+ char *p, *ep;
+ char ntmp[NI_MAXHOST];
+ lwres_uint32_t scopeid;
+#endif
+
+#ifdef LWRES_HAVE_SIN6_SCOPE_ID
+ /*
+ * Scope identifier portion.
+ */
+ ntmp[0] = '\0';
+ if (strchr(hostname, '%') != NULL) {
+ strncpy(ntmp, hostname, sizeof(ntmp) - 1);
+ ntmp[sizeof(ntmp) - 1] = '\0';
+ p = strchr(ntmp, '%');
+ ep = NULL;
+
+ /*
+ * Vendors may want to support non-numeric
+ * scopeid around here.
+ */
+
+ if (p != NULL)
+ scopeid = (lwres_uint32_t)strtoul(p + 1,
+ &ep, 10);
+ if (p != NULL && ep != NULL && ep[0] == '\0')
+ *p = '\0';
+ else {
+ ntmp[0] = '\0';
+ scopeid = 0;
+ }
+ } else
+ scopeid = 0;
+#endif
+
+ if (lwres_net_pton(AF_INET, hostname, (struct in_addr *)abuf)
+ == 1)
+ {
+ if (family == AF_INET6) {
+ /*
+ * Convert to a V4 mapped address.
+ */
+ struct in6_addr *a6 = (struct in6_addr *)abuf;
+ memcpy(&a6->s6_addr[12], &a6->s6_addr[0], 4);
+ memset(&a6->s6_addr[10], 0xff, 2);
+ memset(&a6->s6_addr[0], 0, 10);
+ goto inet6_addr;
+ }
+ addrsize = sizeof(struct in_addr);
+ addroff = (char *)(&SIN(0)->sin_addr) - (char *)0;
+ family = AF_INET;
+ goto common;
+#ifdef LWRES_HAVE_SIN6_SCOPE_ID
+ } else if (ntmp[0] != '\0' &&
+ lwres_net_pton(AF_INET6, ntmp, abuf) == 1)
+ {
+ if (family && family != AF_INET6)
+ return (EAI_NONAME);
+ addrsize = sizeof(struct in6_addr);
+ addroff = (char *)(&SIN6(0)->sin6_addr) - (char *)0;
+ family = AF_INET6;
+ goto common;
+#endif
+ } else if (lwres_net_pton(AF_INET6, hostname, abuf) == 1) {
+ if (family != 0 && family != AF_INET6)
+ return (EAI_NONAME);
+ inet6_addr:
+ addrsize = sizeof(struct in6_addr);
+ addroff = (char *)(&SIN6(0)->sin6_addr) - (char *)0;
+ family = AF_INET6;
+
+ common:
+ ai = ai_clone(ai_list, family);
+ if (ai == NULL)
+ return (EAI_MEMORY);
+ ai_list = ai;
+ ai->ai_socktype = socktype;
+ SIN(ai->ai_addr)->sin_port = port;
+ memcpy((char *)ai->ai_addr + addroff, abuf, addrsize);
+ if (flags & AI_CANONNAME) {
+#if defined(LWRES_HAVE_SIN6_SCOPE_ID)
+ if (ai->ai_family == AF_INET6)
+ SIN6(ai->ai_addr)->sin6_scope_id =
+ scopeid;
+#endif
+ if (lwres_getnameinfo(ai->ai_addr,
+ ai->ai_addrlen, nbuf, sizeof(nbuf),
+ NULL, 0,
+ NI_NUMERICHOST) == 0) {
+ ai->ai_canonname = strdup(nbuf);
+ if (ai->ai_canonname == NULL)
+ return (EAI_MEMORY);
+ } else {
+ /* XXX raise error? */
+ ai->ai_canonname = NULL;
+ }
+ }
+ goto done;
+ } else if ((flags & AI_NUMERICHOST) != 0) {
+ return (EAI_NONAME);
+ }
+ }
+
+ set_order(family, net_order);
+ for (i = 0; i < FOUND_MAX; i++) {
+ if (net_order[i] == NULL)
+ break;
+ err = (net_order[i])(hostname, flags, &ai_list,
+ socktype, port);
+ if (err != 0)
+ return (err);
+ }
+
+ if (ai_list == NULL)
+ return (EAI_NODATA);
+
+done:
+ ai_list = ai_reverse(ai_list);
+
+ *res = ai_list;
+ return (0);
+}
+
+static char *
+lwres_strsep(char **stringp, const char *delim) {
+ char *string = *stringp;
+ char *s;
+ const char *d;
+ char sc, dc;
+
+ if (string == NULL)
+ return (NULL);
+
+ for (s = string; *s != '\0'; s++) {
+ sc = *s;
+ for (d = delim; (dc = *d) != '\0'; d++)
+ if (sc == dc) {
+ *s++ = '\0';
+ *stringp = s;
+ return (string);
+ }
+ }
+ *stringp = NULL;
+ return (string);
+}
+
+static void
+set_order(int family, int (**net_order)(const char *, int, struct addrinfo **,
+ int, int))
+{
+ char *order, *tok;
+ int found;
+
+ if (family) {
+ switch (family) {
+ case AF_INET:
+ *net_order++ = add_ipv4;
+ break;
+ case AF_INET6:
+ *net_order++ = add_ipv6;
+ break;
+ }
+ } else {
+ order = getenv("NET_ORDER");
+ found = 0;
+ while (order != NULL) {
+ /*
+ * We ignore any unknown names.
+ */
+ tok = lwres_strsep(&order, ":");
+ if (strcasecmp(tok, "inet6") == 0) {
+ if ((found & FOUND_IPV6) == 0)
+ *net_order++ = add_ipv6;
+ found |= FOUND_IPV6;
+ } else if (strcasecmp(tok, "inet") == 0 ||
+ strcasecmp(tok, "inet4") == 0) {
+ if ((found & FOUND_IPV4) == 0)
+ *net_order++ = add_ipv4;
+ found |= FOUND_IPV4;
+ }
+ }
+
+ /*
+ * Add in anything that we didn't find.
+ */
+ if ((found & FOUND_IPV4) == 0)
+ *net_order++ = add_ipv4;
+ if ((found & FOUND_IPV6) == 0)
+ *net_order++ = add_ipv6;
+ }
+ *net_order = NULL;
+ return;
+}
+
+static char v4_loop[4] = { 127, 0, 0, 1 };
+
+/*
+ * The test against 0 is there to keep the Solaris compiler
+ * from complaining about "end-of-loop code not reached".
+ */
+#define ERR(code) \
+ do { result = (code); \
+ if (result != 0) goto cleanup; \
+ } while (0)
+
+static int
+add_ipv4(const char *hostname, int flags, struct addrinfo **aip,
+ int socktype, int port)
+{
+ struct addrinfo *ai;
+ lwres_context_t *lwrctx = NULL;
+ lwres_gabnresponse_t *by = NULL;
+ lwres_addr_t *addr;
+ lwres_result_t lwres;
+ int result = 0;
+
+ lwres = lwres_context_create(&lwrctx, NULL, NULL, NULL, 0);
+ if (lwres != LWRES_R_SUCCESS)
+ ERR(EAI_FAIL);
+ (void) lwres_conf_parse(lwrctx, lwres_resolv_conf);
+ if (hostname == NULL && (flags & AI_PASSIVE) == 0) {
+ ai = ai_clone(*aip, AF_INET);
+ if (ai == NULL) {
+ lwres_freeaddrinfo(*aip);
+ ERR(EAI_MEMORY);
+ }
+
+ *aip = ai;
+ ai->ai_socktype = socktype;
+ SIN(ai->ai_addr)->sin_port = port;
+ memcpy(&SIN(ai->ai_addr)->sin_addr, v4_loop, 4);
+ } else {
+ lwres = lwres_getaddrsbyname(lwrctx, hostname,
+ LWRES_ADDRTYPE_V4, &by);
+ if (lwres != LWRES_R_SUCCESS) {
+ if (lwres == LWRES_R_NOTFOUND)
+ goto cleanup;
+ else
+ ERR(EAI_FAIL);
+ }
+ addr = LWRES_LIST_HEAD(by->addrs);
+ while (addr != NULL) {
+ ai = ai_clone(*aip, AF_INET);
+ if (ai == NULL) {
+ lwres_freeaddrinfo(*aip);
+ ERR(EAI_MEMORY);
+ }
+ *aip = ai;
+ ai->ai_socktype = socktype;
+ SIN(ai->ai_addr)->sin_port = port;
+ memcpy(&SIN(ai->ai_addr)->sin_addr,
+ addr->address, 4);
+ if (flags & AI_CANONNAME) {
+ ai->ai_canonname = strdup(by->realname);
+ if (ai->ai_canonname == NULL)
+ ERR(EAI_MEMORY);
+ }
+ addr = LWRES_LIST_NEXT(addr, link);
+ }
+ }
+ cleanup:
+ if (by != NULL)
+ lwres_gabnresponse_free(lwrctx, &by);
+ if (lwrctx != NULL) {
+ lwres_conf_clear(lwrctx);
+ lwres_context_destroy(&lwrctx);
+ }
+ return (result);
+}
+
+static char v6_loop[16] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 };
+
+static int
+add_ipv6(const char *hostname, int flags, struct addrinfo **aip,
+ int socktype, int port)
+{
+ struct addrinfo *ai;
+ lwres_context_t *lwrctx = NULL;
+ lwres_gabnresponse_t *by = NULL;
+ lwres_addr_t *addr;
+ lwres_result_t lwres;
+ int result = 0;
+
+ lwres = lwres_context_create(&lwrctx, NULL, NULL, NULL, 0);
+ if (lwres != LWRES_R_SUCCESS)
+ ERR(EAI_FAIL);
+ (void) lwres_conf_parse(lwrctx, lwres_resolv_conf);
+
+ if (hostname == NULL && (flags & AI_PASSIVE) == 0) {
+ ai = ai_clone(*aip, AF_INET6);
+ if (ai == NULL) {
+ lwres_freeaddrinfo(*aip);
+ ERR(EAI_MEMORY);
+ }
+
+ *aip = ai;
+ ai->ai_socktype = socktype;
+ SIN6(ai->ai_addr)->sin6_port = port;
+ memcpy(&SIN6(ai->ai_addr)->sin6_addr, v6_loop, 16);
+ } else {
+ lwres = lwres_getaddrsbyname(lwrctx, hostname,
+ LWRES_ADDRTYPE_V6, &by);
+ if (lwres != LWRES_R_SUCCESS) {
+ if (lwres == LWRES_R_NOTFOUND)
+ goto cleanup;
+ else
+ ERR(EAI_FAIL);
+ }
+ addr = LWRES_LIST_HEAD(by->addrs);
+ while (addr != NULL) {
+ ai = ai_clone(*aip, AF_INET6);
+ if (ai == NULL) {
+ lwres_freeaddrinfo(*aip);
+ ERR(EAI_MEMORY);
+ }
+ *aip = ai;
+ ai->ai_socktype = socktype;
+ SIN6(ai->ai_addr)->sin6_port = port;
+ memcpy(&SIN6(ai->ai_addr)->sin6_addr,
+ addr->address, 16);
+ if (flags & AI_CANONNAME) {
+ ai->ai_canonname = strdup(by->realname);
+ if (ai->ai_canonname == NULL)
+ ERR(EAI_MEMORY);
+ }
+ addr = LWRES_LIST_NEXT(addr, link);
+ }
+ }
+ cleanup:
+ if (by != NULL)
+ lwres_gabnresponse_free(lwrctx, &by);
+ if (lwrctx != NULL) {
+ lwres_conf_clear(lwrctx);
+ lwres_context_destroy(&lwrctx);
+ }
+ return (result);
+}
+
+void
+lwres_freeaddrinfo(struct addrinfo *ai) {
+ struct addrinfo *ai_next;
+
+ while (ai != NULL) {
+ ai_next = ai->ai_next;
+ if (ai->ai_addr != NULL)
+ free(ai->ai_addr);
+ if (ai->ai_canonname)
+ free(ai->ai_canonname);
+ free(ai);
+ ai = ai_next;
+ }
+}
+
+#ifdef AF_LOCAL
+static int
+get_local(const char *name, int socktype, struct addrinfo **res) {
+ struct addrinfo *ai;
+ struct sockaddr_un *sun;
+
+ if (socktype == 0)
+ return (EAI_SOCKTYPE);
+
+ ai = ai_alloc(AF_LOCAL, sizeof(*sun));
+ if (ai == NULL)
+ return (EAI_MEMORY);
+
+ sun = SUN(ai->ai_addr);
+ strncpy(sun->sun_path, name, sizeof(sun->sun_path));
+
+ ai->ai_socktype = socktype;
+ /*
+ * ai->ai_flags, ai->ai_protocol, ai->ai_canonname,
+ * and ai->ai_next were initialized to zero.
+ */
+
+ *res = ai;
+ return (0);
+}
+#endif
+
+/*
+ * Allocate an addrinfo structure, and a sockaddr structure
+ * of the specificed length. We initialize:
+ * ai_addrlen
+ * ai_family
+ * ai_addr
+ * ai_addr->sa_family
+ * ai_addr->sa_len (LWRES_PLATFORM_HAVESALEN)
+ * and everything else is initialized to zero.
+ */
+static struct addrinfo *
+ai_alloc(int family, int addrlen) {
+ struct addrinfo *ai;
+
+ ai = (struct addrinfo *)calloc(1, sizeof(*ai));
+ if (ai == NULL)
+ return (NULL);
+
+ ai->ai_addr = SA(calloc(1, addrlen));
+ if (ai->ai_addr == NULL) {
+ free(ai);
+ return (NULL);
+ }
+ ai->ai_addrlen = addrlen;
+ ai->ai_family = family;
+ ai->ai_addr->sa_family = family;
+#ifdef LWRES_PLATFORM_HAVESALEN
+ ai->ai_addr->sa_len = addrlen;
+#endif
+ return (ai);
+}
+
+static struct addrinfo *
+ai_clone(struct addrinfo *oai, int family) {
+ struct addrinfo *ai;
+
+ ai = ai_alloc(family, ((family == AF_INET6) ?
+ sizeof(struct sockaddr_in6) : sizeof(struct sockaddr_in)));
+
+ if (ai == NULL) {
+ lwres_freeaddrinfo(oai);
+ return (NULL);
+ }
+ if (oai == NULL)
+ return (ai);
+
+ ai->ai_flags = oai->ai_flags;
+ ai->ai_socktype = oai->ai_socktype;
+ ai->ai_protocol = oai->ai_protocol;
+ ai->ai_canonname = NULL;
+ ai->ai_next = oai;
+ return (ai);
+}
+
+static struct addrinfo *
+ai_reverse(struct addrinfo *oai) {
+ struct addrinfo *nai, *tai;
+
+ nai = NULL;
+
+ while (oai != NULL) {
+ /*
+ * Grab one off the old list.
+ */
+ tai = oai;
+ oai = oai->ai_next;
+ /*
+ * Put it on the front of the new list.
+ */
+ tai->ai_next = nai;
+ nai = tai;
+ }
+ return (nai);
+}