Added ldap_pvt_get_hname. Use instead of ldap_pvt_gethostbyaddr_a when

all you want is the hostname. Supports IPv6 addresses.

libraries/libldap/os-ip.c

@@ -499,7 +499,6 @@ ldap_connect_to_host(LDAP *ld, Sockbuf *sb,
 char *
 ldap_host_connected_to( Sockbuf *sb )
 {
-	struct hostent	*hp;
 	socklen_t		len;
 #ifdef LDAP_PF_INET6
 	struct sockaddr_storage sabuf;
@@ -507,13 +506,9 @@ ldap_host_connected_to( Sockbuf *sb )
 	struct sockaddr sabuf;
 #endif
 	struct sockaddr	*sa = (struct sockaddr *) &sabuf;
-	char			*addr;
-	char			*host;
-
-   	/* buffers for gethostbyaddr_r */
-   	struct hostent	he_buf;
-	int				local_h_errno;
-   	char			*ha_buf=NULL;
+	char			*host = NULL, *herr;
+	char hbuf[NI_MAXHOST];
+	int rc;
 	ber_socket_t	sd;
 
 	(void)memset( (char *)sa, '\0', sizeof sabuf );
@@ -537,31 +532,32 @@ ldap_host_connected_to( Sockbuf *sb )
 #endif
 #ifdef LDAP_PF_INET6
 	case AF_INET6:
-		addr = (char *) &((struct sockaddr_in6 *)sa)->sin6_addr;
-		len = sizeof( struct in6_addr );
+		{
+			struct in6_addr localhost = IN6ADDR_LOOPBACK_INIT;
+			if( memcmp ( &((struct sockaddr_in6 *)sa)->sin6_addr,
+				&localhost, sizeof(localhost)) == 0 )
+			{
+				return LDAP_STRDUP( ldap_int_hostname );
+			}
+		}
 		break;
 #endif
 	case AF_INET:
-		addr = (char *) &((struct sockaddr_in *)sa)->sin_addr;
-		len = sizeof( struct in_addr );
-
 		{
-			struct sockaddr_in localhost;
-			localhost.sin_addr.s_addr = htonl( INADDR_ANY );
+			struct in_addr localhost;
+			localhost.s_addr = htonl( INADDR_ANY );
 
-			if( memcmp ( &localhost.sin_addr,
-				&((struct sockaddr_in *)sa)->sin_addr,
-				sizeof(localhost.sin_addr) ) == 0 )
+			if( memcmp ( &((struct sockaddr_in *)sa)->sin_addr,
+				&localhost, sizeof(localhost) ) == 0 )
 			{
 				return LDAP_STRDUP( ldap_int_hostname );
 			}
 
 #ifdef INADDR_LOOPBACK
-			localhost.sin_addr.s_addr = htonl( INADDR_LOOPBACK );
+			localhost.s_addr = htonl( INADDR_LOOPBACK );
 
-			if( memcmp ( &localhost.sin_addr,
-				&((struct sockaddr_in *)sa)->sin_addr,
-				sizeof(localhost.sin_addr) ) == 0 )
+			if( memcmp ( &((struct sockaddr_in *)sa)->sin_addr,
+				&localhost, sizeof(localhost) ) == 0 )
 			{
 				return LDAP_STRDUP( ldap_int_hostname );
 			}
@@ -574,15 +570,13 @@ ldap_host_connected_to( Sockbuf *sb )
 		break;
 	}
 
-	host = NULL;
-	if ((ldap_pvt_gethostbyaddr_a( addr, len, sa->sa_family,
-		&he_buf, &ha_buf, &hp, &local_h_errno ) == 0 ) &&
-		(hp != NULL) && ( hp->h_name != NULL ) )
+	hbuf[0] = 0;
+	if (ldap_pvt_get_hname( sa, len, hbuf, sizeof(hbuf), &herr ) == 0 &&
+		hbuf[0] ) 
 	{
-		host = LDAP_STRDUP( hp->h_name );   
+		host = LDAP_STRDUP( hbuf );   
 	}
 
-	LDAP_FREE( ha_buf );
 	return host;
 }
 #endif

libraries/libldap/util-int.c

@@ -178,7 +178,125 @@ int ldap_pvt_gethostbyname_a(
 	return -1;
 #endif	
 }
-	 
+
+#ifndef GETNAMEINFO
+static const char *
+hp_strerror( int err )
+{
+	switch (err) {
+	case HOST_NOT_FOUND:	return "Host not found (authoritative)";
+	case TRY_AGAIN:		return "Host not found (server fail?)";
+	case NO_RECOVERY:	return "Non-recoverable failure";
+	case NO_DATA:		return "No data of requested type";
+#ifdef NETDB_INTERNAL
+	case NETDB_INTERNAL:	return STRERROR( errno );
+#endif
+	default:	break;	
+	}
+	return "Unknown resolver error";
+}
+#endif
+
+int ldap_pvt_get_hname(
+	const struct sockaddr *sa,
+	int len,
+	char *name,
+	int namelen,
+	char **err )
+{
+	int rc;
+#if defined( HAVE_GETNAMEINFO )
+
+#if defined( LDAP_R_COMPILE )
+	ldap_pvt_thread_mutex_lock( &ldap_int_resolv_mutex );
+#endif
+	rc = getnameinfo( sa, len, name, namelen, NULL, 0, 0 );
+#if defined( LDAP_R_COMPILE )
+	ldap_pvt_thread_mutex_unlock( &ldap_int_resolv_mutex );
+#endif
+	if ( rc ) *err = AC_GAI_STRERROR( rc );
+	return rc;
+
+#else /* !HAVE_GETNAMEINFO */
+	char *addr;
+	int alen;
+	struct hostent *hp = NULL;
+#ifdef HAVE_GETHOSTBYADDR_R
+	struct hostent hb;
+	int buflen=BUFSTART, h_errno;
+	char *buf=NULL;
+#endif
+
+#ifdef LDAP_PF_INET6
+	if (sa->sa_family == AF_INET6) {
+		struct sockaddr_in6 *sin = (struct sockaddr_in6 *)sa;
+		addr = (char *)&sin->sin6_addr;
+		alen = sizeof(sin->sin6_addr);
+	} else
+#endif
+	if (sa->sa_family == AF_INET) {
+		struct sockaddr_in *sin = (struct sockaddr_in *)sa;
+		addr = (char *)&sin->sin_addr;
+		alen = sizeof(sin->sin_addr);
+	} else {
+		rc = NO_RECOVERY;
+		*err = hp_strerror( rc );
+		return rc;
+	}
+#if defined( HAVE_GETHOSTBYADDR_R )
+	for(;buflen<BUFMAX;) {
+		if (safe_realloc( &buf, buflen )==NULL) {
+			*err = STRERROR( ENOMEM );
+			return ENOMEM;
+		}
+#if (GETHOSTBYADDR_R_NARGS < 8)
+		hp=gethostbyaddr_r( addr, alen, sa->sa_family,
+			&hb, buf, buflen, &h_errno );
+		rc = (hp == NULL) ? -1 : 0;
+#else
+		rc = gethostbyaddr_r( addr, alen, sa->sa_family,
+			&hb, buf, buflen, 
+			&hp, &h_errno );
+#endif
+#ifdef NETDB_INTERNAL
+		if ((rc<0) &&
+			(h_errno==NETDB_INTERNAL) &&
+			(errno==ERANGE))
+		{
+			buflen*=2;
+			continue;
+		}
+#endif
+		break;
+	}
+	if (hp) {
+		strncpy( name, hp->h_name, namelen );
+	} else {
+		*err = hp_strerror( h_errno );
+	}
+	LDAP_FREE(buf);
+#else /* HAVE_GETHOSTBYADDR_R */
+
+#if defined( LDAP_R_COMPILE )
+	ldap_pvt_thread_mutex_lock( &ldap_int_resolv_mutex );
+#endif
+	hp = gethostbyaddr( addr, alen, sa->sa_family );
+	if (hp) {
+		strncpy( name, hp->h_name, namelen );
+		rc = 0;
+	} else {
+		rc = h_errno;
+		*err = hp_strerror( h_errno );
+	}
+#if defined( LDAP_R_COMPILE )
+	ldap_pvt_thread_mutex_unlock( &ldap_int_resolv_mutex );
+#endif
+
+#endif	/* !HAVE_GETHOSTBYADDR_R */
+	return rc;
+#endif	/* !HAVE_GETNAMEINFO */
+}
+
 int ldap_pvt_gethostbyaddr_a(
 	const char *addr,
 	int len,